Effects of some factors on electro-osmotic dewatering of Laterite ...

African Journals Online (AJOL)

... effect on the EO process. The general effects were same for the two soil samples, but the rate of the effect varied, which implied that EO dewatering was site dependent. It was concluded that EO dewatering was a viable option for dewatering of tropical laterite. Keywords: Electro-osmosis, Soil Dewatering, Tropical Laterite, ...

Environmental de-watering of fluid fine tailings

Energy Technology Data Exchange (ETDEWEB)

Wilson, G.W. [Alberta Univ., Edmonton, AB (Canada). Geotechnical Center

2010-07-01

This presentation reported on a surface deposition method of dewatering mature fine tailings (MFT). MFTs typically have a solids content of 35 percent. Solids contents of 60 percent or greater have been shown to produce desirable physical properties. Dewatering was considered as a flux boundary problem. Dewatering a 1.0 meter thick profile of MFT with an initial solids content of 35 percent required approximately 200 mm per 1 m{sup 2} of water to exit the boundaries of the profile. The flux boundary conditions were driven by atmospheric forcing events associated with freeze-thaw effects and evaporative drying, and were also influenced by the drainage of liquid water caused by run-off and foundation seepage. The relative contributions of the dewatering mechanisms were discussed and quantified. tabs., figs.

Conhecimento - solidariedade como um saber docente na modalidade EAD: atitudes, valores e condições / Solidarity here know how a teaching in modalidade EAD: attitudes, values and conditions

Directory of Open Access Journals (Sweden)

Regina Trilho Otero Xavier

2007-01-01

Full Text Available O presente artigo relata uma investigação que pesquisa a construção do conhecimento-solidariedade em EaD. O objetivo principal do estudo é contribuir para a implementação de ações pedagógicas em EaD na perspectiva do conhecimentosolidariedade.A partir, principalmente, dos referenciais de Boaventura Santos, JeanPiaget e Yves de La Taille procura-se compreender o que vem a ser o conhecimentosolidariedade, bem como os valores e saberes que favorecem seu desenvolvimento em ações pedagógicas de professores e alunos em EaD. Os estudos apontam que agir de acordo com o conhecimento-solidariedade exige competência cognitiva (saber sersolidário, competência afetiva (querer ser solidário e, ainda, um contexto favorável (poder ser solidário. As conclusões evidenciam que o conhecimento–solidariedade, em ações pedagógicas na modalidade EaD, está fortemente vinculado aos saberes éticos, técnicos, pedagógicos, comunicacionais e de gestão; que se trata de um saber construído progressivamente, em experiências permeadas por respeito mútuo, reciprocidade e empatia, tendo a cooperação como principal estratégia. Mas, e fundamentalmente, que ocorrência de ações, na perspectiva do conhecimento-solidariedade, é dependente decontextos individuais de origem complexa, pois envolvem a interação de vários aspectos interligados (como: hábitos, valores, sentimentos, capacidades,... e de contextos coletivos dinâmicos (como ambientes cooperativos ou coercitivos, entre pares ou “superiores”, na presença de autoridade que incentiva ou que desfavorece a solidariedade.Abstract This article reports on an investigation that the search of knowledge-building solidarity in EaD. The main objective of the study is to contribute to the implementation of educational activities in EaD the perspective of knowledge-solidarity. From mainly on the benchmarks of Boaventura Santos, Jean Piaget and Yves de La Taille seeks to understand what has to be

Electroacoustic oscillations in the LEP SC. cavities

CERN Document Server

Boussard, Daniel; Tückmantel, Joachim

1996-01-01

The LEP superconducting cavities have been plagued by electroacoustic oscillations. Tests have been done to eliminate these by a special feed-back loop in the tuning circuit as well as a feed-forward path, but they could only be eliminated safely up to the design field by running the cavities close to tune neglecting beam-loading compensation. This technique proved successful during the first LEP2 test run at 70 GeV. The mechanism and essential parameters driving these oscillations have been analysed as well as the corresponding stronger loading of the power coupler.

Electroosmotically enhanced sludge dewatering-pilot-plant study

CSIR Research Space (South Africa)

Smollen, M

1994-01-01

Full Text Available role in determining the ease or difficulty of phase separation. It seems that the inefficiency of dewatering applied to gelatinous and fine-particle sludges can be overcome by mechanical dewatering enhanced by electroosmosis. A prototype pilot-plant...

Optimizing MFT dewatering by controlling polymer mixing

Energy Technology Data Exchange (ETDEWEB)

Demoz, A.; Munoz, V.; Mikula, R. [Natural Resources Canada, Devon, AB (Canada). CANMET Western Research Centre

2010-07-01

A method of controlling polymer mixing for the dewatering of mature fine tailings (MFT) was presented. The method was developed to accelerate water release from MFT and to recover more water for re-use. Dewatering rates are dependent upon hydrodynamic conditions as well as various physical mixing variables. The effect of mixing energy on the rate and amount of released water flocculated MFT was investigated using different impellers in order to determine the release water amount and capillary suction time. The mixing energy effect on the structure of the flocculated MFT was analyzed using rheology and stereo microscopy techniques. Batch mixing tests were conducted to determine dewatering characteristics. Flow was described using the Herschel-Bulkley model. Results of the study demonstrated a clear peak in the amount of water released with the mixing time. The effect was applicable to rim-ditch thin-lift, and dewatering by centrifugation. tabs., figs.

DEVELOPMENT OF DEWATERING AIDS FOR MINERALS AND COAL FINES

Energy Technology Data Exchange (ETDEWEB)

Roe-Hoam Yoon; Ramazan Asmatulu; Ismail Yildirim; William Jansen; Jinmig Zhang; Brad Atkinson; Jeff Havens

2004-07-01

MCT has developed a suite of novel dewatering chemicals (or aids) that are designed to cause a decrease in the capillary pressures of the water trapped in a filter cake by (1) decreasing the surface tension of water, (2) increasing the contact angles of the particles to be dewatered, and (3) causing the particles to coagulate, all at the same time. The decrease in capillary pressure in turn causes an increase in the rate filtration, an increase in throughput, and a decrease in pressure drop requirement for filtration. The reagents are used frequently as blends of different chemicals in order to bring about the changes in all of the process variables noted above. The minerals and coal samples tested in the present work included copper sulfide, lead sulfide, zinc sulfide, kaolin clay, talc, and silica. The laboratory-scale test work included studies of reagent types, drying cycle times, cake thickness, slurry temperature, conditioning intensity and time, solid content, and reagent dosages. To better understand the mechanisms involved, fundamental studies were also conducted. These included the measurements of the contact angles of the particles to be dewatered (which are the measures of particle hydrophobicity) and the surface tensions of the filtrates produced from dewatering tests. The results of the laboratory-scale filtration experiments showed that the use of the novel dewatering aids can reduce the moistures of the filter cake by 30 to 50% over what can be achieved using no dewatering aids. In many cases, such high levels of moisture reductions are sufficient to obviate the needs for thermal drying, which is costly and energy intensive. Furthermore, the use of the novel dewatering aids cause a substantial increase in the kinetics of dewatering, which in turn results in increased throughput. As a result of these technological advantages, the novel dewatering aids have been licensed to Nalco, which is one of the largest mining chemicals companies of the world. At

POC-scale testing of an advanced fine coal dewatering equipment/technique

Energy Technology Data Exchange (ETDEWEB)

Groppo, J.G.; Parekh, B.K. [Univ. of Kentucky, Lexington, KY (United States); Rawls, P. [Department of Energy, Pittsburgh, PA (United States)

1995-11-01

Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 {mu}m) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20 percent level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20 percent or lower moisture using either conventional or advanced dewatering techniques. As the contract title suggests, the main focus of the program is on proof-of-concept testing of a dewatering technique for a fine clean coal product. The coal industry is reluctant to use the advanced fine coal recovery technology due to the non-availability of an economical dewatering process. in fact, in a recent survey conducted by U.S. DOE and Battelle, dewatering of fine clean coal was identified as the number one priority for the coal industry. This project will attempt to demonstrate an efficient and economic fine clean coal slurry dewatering process.

Stochastic Alternating Dynamics for Synchronous EAD-Like Beating Rhythms in Cultured Cardiac Myocytes

Institute of Scientific and Technical Information of China (English)

ZHANG Ning; ZHANG Hui-Min; LIU Zhi-Qiang; DING Xue-Li; YANG Ming-Hao; GU Hua-Guang; REN Wei

2009-01-01

Dissolved cardiac myocytes can couple together and generate synchronous beatings in culture. We observed a synchronized early after-depolarization(EAD)-like rhythm in cultured cardiac myocytes and reproduced the experimental observation in a network mathematical model whose dynamics are close to a Hopf bifurcation. The mechanism for this EAD-like rhythm is attributed to noised-induced stochastic alternatings between the focus and the limit cycle. These results provide novel understandings for pathological heart rhythms like the early immature beatings.

Evaluation of the sensitivity of electro-acoustic measurements for process monitoring and control of an atmospheric pressure plasma jet system

Energy Technology Data Exchange (ETDEWEB)

Law, V J [Dublin City University, National Centre of Plasma Science and Technology, Collins Avenue, Glasnevin, Dublin 9, Dublin (Ireland); O' Neill, F T; Dowling, D P, E-mail: vic.law@dcu.ie [School Mechanical and Materials Engineering, University College Dublin, Belfield, Dublin 4 (Ireland)

2011-06-15

The development of non-invasive process diagnostic techniques for the control of atmospheric plasmas is a critical issue for the wider adoption of this technology. This paper evaluates the use of a frequency-domain deconvolution of an electro-acoustic emission as a means to monitor and control the plasma formed using an atmospheric pressure plasma jet (APPJ) system. The air plasma system investigated was formed using a PlasmaTreat(TM) OpenAir applicator. Change was observed in the electro-acoustic signal with changes in substrate type (ceramic, steel, polymer). APPJ nozzle to substrate distance and substrate feature size were monitored. The decoding of the electro-acoustic emission yields three subdatasets that are described by three separate emission mechanisms. The three emissions are associated with the power supply fundamental drive frequency and its harmonics, the APPJ nozzle longitudinal mode acoustic emission and its odd overtones, and the acoustic surface reflection that is produced by the impedance mismatch between the discharge and the surface. Incorporating this knowledge into a LabVIEW program facilitated the continuous deconvolution of the electro-acoustic data. This enabled the use of specific frequency band test limits to control the APPJ treatment process which is sensitive to both plasma processing conditions and substrate type and features.

Maximizing the benefits of a dewatering system

International Nuclear Information System (INIS)

Matthews, P.; Iverson, T.S.

1999-01-01

The use of dewatering systems in the mining, industrial sludge and sewage waste treatment industries is discussed, also describing some of the problems that have been encountered while using drilling fluid dewatering technology. The technology is an acceptable drilling waste handling alternative but it has had problems associated with recycled fluid incompatibility, high chemical costs and system inefficiencies. This paper discussed the following five action areas that can maximize the benefits and help reduce costs of a dewatering project: (1) co-ordinate all services, (2) choose equipment that fits the drilling program, (3) match the chemical treatment with the drilling fluid types, (4) determine recycled fluid compatibility requirements, and (5) determine the disposal requirements before project start-up. 2 refs., 5 figs

Advantages and Challenges of Relaxor-PbTiO3 Ferroelectric Crystals for Electroacoustic Transducers- A Review

Science.gov (United States)

Zhang, Shujun; Li, Fei; Jiang, Xiaoning; Kim, Jinwook; Luo, Jun; Geng, Xuecang

2014-01-01

Relaxor-PbTiO3 (PT) based ferroelectric crystals with the perovskite structure have been investigated over the last few decades due to their ultrahigh piezoelectric coefficients (d33 > 1500 pC/N) and electromechanical coupling factors (k33 > 90%), far outperforming state-of-the-art ferroelectric polycrystalline Pb(Zr,Ti)O3 ceramics, and are at the forefront of advanced electroacoustic applications. In this review, the performance merits of relaxor-PT crystals in various electroacoustic devices are presented from a piezoelectric material viewpoint. Opportunities come from not only the ultrahigh properties, specifically coupling and piezoelectric coefficients, but through novel vibration modes and crystallographic/domain engineering. Figure of merits (FOMs) of crystals with various compositions and phases were established for various applications, including medical ultrasonic transducers, underwater transducers, acoustic sensors and tweezers. For each device application, recent developments in relaxor-PT ferroelectric crystals were surveyed and compared with state-of-the-art polycrystalline piezoelectrics, with an emphasis on their strong anisotropic features and crystallographic uniqueness, including engineered domain - property relationships. This review starts with an introduction on electroacoustic transducers and the history of piezoelectric materials. The development of the high performance relaxor-PT single crystals, with a focus on their uniqueness in transducer applications, is then discussed. In the third part, various FOMs of piezoelectric materials for a wide range of ultrasound applications, including diagnostic ultrasound, therapeutic ultrasound, underwater acoustic and passive sensors, tactile sensors and acoustic tweezers, are evaluated to provide a thorough understanding of the materials’ behavior under operational conditions. Structure-property-performance relationships are then established. Finally, the impacts and challenges of relaxor

Onsager’s reciprocal relations in electrolyte solutions. I. Sedimentation and electroacoustics

Energy Technology Data Exchange (ETDEWEB)

Gourdin-Bertin, S.; Bernard, O.; Jardat, M. [Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire PHENIX, Case 51, 4 Place Jussieu, F-75005 Paris (France); Chassagne, C. [Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire PHENIX, Case 51, 4 Place Jussieu, F-75005 Paris (France); Environmental Fluid Mechanics, Faculty of Civil Engineering and Geosciences, Delft University of Technology, 2600 GA Delft (Netherlands)

2015-08-14

In the framework of irreversible thermodynamics, we show that the sedimentation current in electrolyte solutions is mathematically equivalent to the low frequency limit of the ionic vibration current, appearing in the presence of an acoustic wave. This non-trivial result is obtained thanks to a careful choice of the reference frame used to express the mass fluxes in the context of electroacoustics. Coupled transport phenomena in electrolyte solutions can also be investigated in a mechanical framework, with a set of Newtonian equations for the dynamics of charged solutes. Both in the context of sedimentation and of electroacoustics, we show that the results obtained in the mechanical framework, in the ideal case (i.e., without interactions between ions), do satisfy the Onsager’s reciprocal relations. We also derive the general relation between corrective forces accounting for ionic interactions which must be fulfilled so that the Onsager’s reciprocal relations are verified. Finally, we show that no additional diffusion term needs to be taken into account in the flux of solutes (far from the walls), even if local concentration gradients exist, contrarily to what was done previously in the literature.

O tutor em EAD: papéis e atribuições

Directory of Open Access Journals (Sweden)

Jorge Adriano Pires Silva

2016-02-01

Full Text Available A proposta de reflexão feita neste trabalho diz respeito a um tema de grande repercussão atual: a Educação a Distância (EAD. Procura-se refletir aqui sobre os agentes envolvidos nessa modalidade de ensino não tão recente e que vem se expandindo muito devido, principalmente, ao avanço e modernização da tecnologia. Neste trabalho, lança-se foco aos tutores presenciais e à distância, procurando elucidar suas atribuições e relevância no contexto da EAD. Os tutores são peças fundamentais para a articulação e sucesso de todo o processo de ensino-aprendizagem nessa modalidade de ensino. A eles cabe o amparo didático, pedagógico, pessoal, crítico e tecnológico dos acadêmicos de modo virtual ou presencial. Por meio de uma pesquisa de cunho bibliográfico e exploratório, com bases fundamentadas na literatura pertinente, intenta-se analisar as ações do tutor no ambiente de aprendizagem da EAD, identificando seus papeis e entendendo sua importância no processo de ensino-aprendizagem na modalidade à distância.

The utilization of forward osmosis for coal tailings dewatering

Science.gov (United States)

The feasibility of dewatering coal tailings slurry by forward osmosis (FO) membrane process was investigated in this research. A prototype cell was designed and used for the dewatering tests. A cellulosic FO membrane (Hydration Technology Innovations, LLC, Albany, OR) was used fo...

Electroacoustical simulation of listening room acoustics for project ARCHIMEDES

DEFF Research Database (Denmark)

Bech, Søren

1989-01-01

ARCHIMEDES is a psychoacoustics research project, funded under the European EUREKA scheme. Three partners share the work involved: The Acoustics Laboratory of The Technical University of Denmark; Bang and Olufsen of Denmark; and KEF Electronics of England. Its primary object is to quantify...... the influence of listening room acoustics on the timbre of reproduced sound. For simulation of the acoustics of a standard listening room, an electroacoustic setup has been built in an anechoic chamber. The setup is based on a computer model of the listening room, and it consists of a number of loudspeakers...

Techno-economic evaluation of microalgae harvesting and dewatering systems

NARCIS (Netherlands)

Fasaei, F.; Bitter, J.H.; Slegers, P.M.; Boxtel, van A.J.B.

2018-01-01

Microalgal biomass is processed into products by two main process steps: 1) harvesting and dewatering; and 2) extraction, fractionation and conversion. The performance of unit operations for harvesting and dewatering is often expressed in qualitative terms, like “high energy consumption” and “low in

Caisson disease during the construction of the Eads and Brooklyn Bridges: A review.

Science.gov (United States)

Butler, W P

2004-01-01

The Eads Bridge (St. Louis) and the Brooklyn Bridge (New York City) were testing grounds for caisson construction. These caissons were enormous compressed air boxes used to build riverine piers and abutments anchoring the bridges. Caisson meant faster and cheaper construction, but there was a hidden cost---caisson disease (decompression sickness). Within caissons, workers labored at pressures as high as 55 psig and caisson disease was common. This discourse is a brief history of the caisson, a brief discussion of the illness as viewed in the mid 1800's, and an abbreviated history of the Eads and Brooklyn Bridges. It also provides a detailed description and evaluation of the observations, countermeasures, and recommendations of Dr. Alphonse Jaminet, the Eads Bridge physician, and Dr. Andrew Smith, the Brooklyn Bridge physician, who published reports of their experience in 1871 and 1873, respectively. These and other primary sources permit a detailed examination of early caisson disease and Jaminet's and Smith's thinking also serve as good examples from which to study and learn.

Electroacoustic miniaturized DNA-biosensor.

Science.gov (United States)

Gamby, Jean; Lazerges, Mathieu; Pernelle, Christine; Perrot, Hubert; Girault, Hubert H; Tribollet, Bernard

2007-11-01

A micrometer-sized electroacoustic DNA-biosensor was developed. The device included a thin semi-crystalline polyethylene terephthalate (PET) dielectric layer with two Ag microband electrodes on one side and a DNA thiol-labeled monolayer adsorbed on a gold surface on the other. A resonance wave was observed at 29 MHz with a network analyzer, upon AC voltage application between the two Ag electrodes, corresponding to electromechanical coupling induced by molecular dipoles of the PET polymer chain in the dielectric layer. It was found that the device size and geometry were well adapted to detect DNA hybridization, by measuring the capacity of the resonance response evolution: hybridization induced polarization of the dielectric material that affected the electromechanical coupling established in the dielectric layer. The 0.2 mm(2) sensor sensitive area allows detection in small volumes and still has higher detection levels for bioanalytical applications, the non-contact configuration adopted avoids electric faradic reactions that may damage biosensor sensitive layers, and finally, PET is a costless raw material, easy to process and well adapted for large scale production. The well-balanced technological and economic advantages of this kind of device make it a good candidate for biochip integration.

Dewatering blastholes cuts explosives costs

Energy Technology Data Exchange (ETDEWEB)

Pilshaw, S.R.

1987-11-01

Large mining operations often require a combination of presplitting and dewatering with blasthole pumps. Increasing the percentage of bulk ANFO in any blast will reduce cost and should increase profitability.

Professor ou tutor: uma linha tênue na docência em EAD

Directory of Open Access Journals (Sweden)

Michelle Brust Hackmayer

2014-06-01

Full Text Available Este trabalho analisa a natureza docente do trabalho de tutoria na Educação a Distância (EAD, utilizando, como referência, os documentos oficiais do Ministério da Educação e Cultura (MEC (Brasil, 2007 sobre as funções do tutor e as avaliações que os tutores do Centro de Educação Superior a Distância do Estado do Rio de Janeiro (CEDERJ fazem de sua prática. Contextualiza a pesquisa, abordando questões teóricas relativas à docência na EAD, a qual envolve vários profissionais em sua atuação, incluindo o tutor. Revela que até o momento inexiste um termo que defina o papel do tutor no trabalho com a EAD, papel este que se torna cada vez maior e mais indefinido. Mostra que, embora tenha, reconhecidamente, uma função importante e determinante nos cursos a distância, o tutor ainda é um profissional que carece de perfil profissiográfico, que lhe confira uma formação definida e um espaço determinado na modalidade. O artigo revela, ainda, que cresce a necessidade de estudos que indiquem quais as suas principais funções, sua identidade profissional e, sobretudo, a caracterização de sua atuação docente na EAD. Analisa as respostas do questionário aplicado aos 38 tutores do CEDERJ/UERJ, no curso de Licenciatura em Pedagogia e, finalmente, conclui que os tutores são unânimes em considerar sua atuação como docente, embora não sejam reconhecidos nem remunerados como tal pela instituição onde atuam.

CONHECIMENTO-SOLIDARIEDADE COMO UM SABER DOCENTE NA MODALIDADE EAD: ATITUDES, VALORES E CONDIÇÕES

Directory of Open Access Journals (Sweden)

Regina Trilho Otero Xavier

2008-07-01

Full Text Available O presente artigo relata uma investigação que pesquisa a construção do conhecimento-solidariedade em EAD. O objetivo principal do estudo é contribuir para a implementação de ações pedagógicas em EAD na perspectiva do conhecimento-solidariedade. A partir, principalmente, dos referenciais de Boaventura Santos, Jean Piaget e Yves de La Taille procura-se compreender o que vem a ser o conhecimento-solidariedade, bem como os valores e saberes que favorecem seu desenvolvimento em ações pedagógicas de professores e alunos em EAD. Os estudos apontam que agir de acordo com o conhecimento-solidariedade exige competência cognitiva (saber ser solidário, competência afetiva (querer ser solidário e, ainda, um contexto favorável (poder ser solidário. As conclusões evidenciam que o conhecimento–solidariedade, em ações pedagógicas na modalidade EAD, está fortemente vinculado aos saberes éticos, técnicos, pedagógicos, comunicacionais e de gestão; que se trata de um saber construído progressivamente, em experiências permeadas por respeito mútuo, reciprocidade e empatia, tendo a cooperação como principal estratégia. Mas, e fundamentalmente, que a ocorrência de ações, na perspectiva do conhecimento-solidariedade, é dependente de contextos individuais de origem complexa, pois envolvem a interação de vários aspectos interligados (como: hábitos, valores, sentimentos, capacidades,... e de contextos coletivos dinâmicos (como ambientes cooperativos ou coercitivos, entre pares ou “superiores”, na presença de autoridade que incentiva ou que desfavorece a solidariedade. Palavras-chave: EaD, solidariedade, saberes docentes.

A COMUNICAÇÃO NA EAD: UM DIÁLOGO DE APRENDIZAGEM

Directory of Open Access Journals (Sweden)

Renata Aparecida Pereira Teodoro

2017-02-01

Full Text Available Trata-se de um estudo bibliográfico que tem por objetivo analisar como a comunicação entre o tutor e o aluno e também entre os alunos, é fundamental no processo de ensino-aprendizagem. O diálogo proporciona motivação, troca de experiência e aprendizagem interativa. As tecnologias de Informação e Comunicação (TICs consistem em um eixo de sustentação da Educação à distância (EAD. A inovação permitiu a comunicação efetiva no processo de aprendizado, por meio de ferramentas como fóruns de discussão, chats, wikis, videoconferências, alguns recursos imprescindíveis na mediação do conhecimento, através da EAD.

Dewatering and Treatment of Septage Using Vertical Flow Constructed Wetlands

Directory of Open Access Journals (Sweden)

Yee Yong Tan

2017-10-01

Full Text Available The vertical flow constructed wetland (VFCW has become an attractive decentralised technology for septage treatment. One of the main purposes of the septage treatment is to reduce the volume of raw septage through dewatering, where the solids content is retained in the wetland bed and the water content is released. The retention of solids forms a layer of sludge deposit at the wetland surface, and the drained water, the so-called leachate, typically contains a lower solids content. This article reports the performance of dewatering and filtration of a pilot-scale VFCW designed for septage treatment. A comparison between two feeding strategies, hydraulic loading rate (HLR and solids loading rate (SLR, is presented. The dewatering efficiency through drainage was found to be dependent on the solids load. The removal of total solids (TS and chemical oxygen demand (COD were excellent as the quality of leachate showed that more than 90% of TS and COD were retained in the system. This study reveals that the feeding based on SLR delivered a more sustainable performance for dewatering and solids removal. The build-up of sludge deposit significantly deteriorated the dewatering efficiency through drainage, but it tended to improve the filtration capacity.

Microalgae dewatering based on forward osmosis employing proton exchange membrane.

Science.gov (United States)

Son, Jieun; Sung, Mina; Ryu, Hoyoung; Oh, You-Kwan; Han, Jong-In

2017-11-01

In this study, electrically-facilitated forward osmosis (FO) employing proton exchange membrane (PEM) was established for the purpose of microalgae dewatering. An increase in water flux was observed when an external voltage was applied to the FO equipped with the PEM; as expected, the trend became more dramatic with both concentration of draw solution and applied voltage raised. With this FO used for microalgae dewatering, 247% of increase in flux and 86% in final biomass concentration were observed. In addition to the effect on flux improvement, the electrically-facilitated FO exhibited the ability to remove chlorophyll from the dewatered biomass, down to 0.021±0015mg/g cell. All these suggest that the newly suggested electrically-facilitated FO, one particularly employed PEM, can indeed offer a workable way of dewatering of microalgae; it appeared to be so because it can also remove the ever-problematic chlorophyll from extracted lipids in a simultaneous fashion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Macroinvertebrate community responses to a dewatering disturbance gradient in a restored stream

Directory of Open Access Journals (Sweden)

J. D. Muehlbauer

2011-06-01

Full Text Available Dewatering disturbances are common in aquatic systems and represent a relatively untapped field of disturbance ecology, yet studying dewatering events along gradients in non-dichotomous (i.e. wet/dry terms is often difficult. Because many stream restorations can essentially be perceived as planned hydrologic manipulations, such systems can make ideal test-cases for understanding processes of hydrological disturbance. In this study we used an experimental drawdown in a 440 ha stream/wetland restoration site to assess aquatic macroinvertebrate community responses to dewatering and subsequent rewetting. The geomorphic nature of the site and the design of the restoration allowed dewatering to occur predictably along a gradient and decoupled the hydrologic response from any geomorphic (i.e. habitat heterogeneity effects. In the absence of such heterogeneous habitat refugia, reach-scale wetted perimeter and depth conditions exerted a strong control on community structure. The community exhibited an incremental response to dewatering severity over the course of this disturbance, which was made manifest not as a change in community means but as an increase in community variability, or dispersion, at each site. The dewatering also affected inter-species abundance and distributional patterns, as dewatering and rewetting promoted alternate species groups with divergent habitat tolerances. Finally, our results indicate that rapid rewetting – analogous to a hurricane breaking a summer drought – may represent a recovery process rather than an additional disturbance and that such processes, even in newly restored systems, may be rapid.

Microbiological and physico-chemical studies on irradiated dewatered sludge

International Nuclear Information System (INIS)

Hilmy, N.; Suwirma, S.; Harsoyo; Suhadi, F.

1987-01-01

Microbiological and physico-chemical studies on irradiated dewatered sludge. Microbiological and physico-chemical dewatered have been carried out and non-irradiated dewatered sludge of Jakarta city, collected during the rainy and dry season. Total bacterial counts of non-irradiated dewatered sludge with water content of around 20%, were found to be about 7x10 8 per g during the rainy season and 7x10 6 up to 1.3x10 8 per g during the dry season, while coliform fecal Streptococcus and Pseudomonas were found to be 1.6x10 4 to 1.0x10 7 , 3x10 5 , and 5x10 3 per g, respectively. No Salmonella, Shigella and Vibrio were detected in all of the samples observed. About 10% of the total number of coliforms were found to be Escherichia coli. A dose of 6 kGy could eliminate the coliform, E. Coli, fecal Streptococcus and Pseudomonas from all of the dewatered sludge observed. The nutrient value of the sludge was sufficient, i.e. total nitrogen content ranged between 1 and 4,42%, phosphorus between 1.55 and 2.36%, and potassium between 0,1 and 0,2% of dry matter. Heavy metal contents were found a little bit high to be applied as animal feed, but it is still acceptable for soil conditioner. Combining 3 months storage at ambient environment and irradiation dose of 2.5 kGy were found to work synergistically to eliminate coliforms and E. Coli from sludge. (author). 8 figs, 17 refs

Electrical field: a historical review of its application and contributions in wastewater sludge dewatering.

Science.gov (United States)

Mahmoud, Akrama; Olivier, Jérémy; Vaxelaire, Jean; Hoadley, Andrew F A

2010-04-01

Electric field-assisted dewatering, also called electro-dewatering, is a technology in which a conventional dewatering mechanism such a pressure dewatering is combined with electrokinetic effects to realize an improved liquid/solids separation, to increase the final dry solids content and to accelerate the dewatering process with low energy consumption compared to thermal drying. Electro-dewatering is not a new idea, but the practical industrial applications have been limited to niche areas in soil mechanics, civil engineering, and the ceramics industry. Recently, it has received great attention, specially, in the fields of fine-particle sludge, gelatinous sludge, sewage sludge, pharmaceutical industries, food waste and bull kelp, which could not be successfully dewatered with conventional mechanical methods. This review focuses on the scientific and practical aspects of the application of an electrical field in laboratory/industrial dewatering, and discusses this in relation to conventional dewatering techniques. A comprehensive bibliography of research in the electro-dewatering of wastewater sludges is included. As the fine-particle suspensions possess a surface charge, usually negative, they are surrounded by a layer with a higher density of positive charges, the electric double layer. When an electric field is applied, the usually negative charged particles move towards the electrode of the opposite charge. The water, commonly with cations, is driven towards the negative electrode. Electro-dewatering thus involves the well-known phenomena of electrophoresis, electro-osmosis, and electromigration. Following a detailed outline of the role of the electric double layer and electrokinetic phenomena, an analysis of the components of applied voltage and their significance is presented from an electrochemical viewpoint. The aim of this elementary analysis is to provide a fundamental understanding of the different process variables and configurations in order to

Determination of Juice Removal Difficulty from Mash Cake in Cassava Mash Dewatering Operation

Directory of Open Access Journals (Sweden)

Oladele Peter KOLAWOLE

2012-08-01

Full Text Available Cassava processing equipment operators have limited knowledge; this militates against the success recorded in the research so far in cassava mash dewatering. New dewatering schemes to make food processing economical to handle are in progress. Common dewatering processes use a variety of mechanical means such as screw presses and belt presses. Experiments were conducted using three samples of TMS 4(2 1425 variety while evaluating the difficulty of separating juice from mash cake. Average specific cake resistance (a of 5×1011 m/kg was obtained confirming that it is moderately easy to dewatering.

Enhanced Brine Dewatering System, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The purpose of the Enhanced Brine Dewatering System (EBDS) is to provide an easily scalable means of completely recovering usable water from byproducts created by...

Enhanced Brine Dewatering System, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — The purpose of the Enhanced Brine Dewatering System (EBDS) is to provide a scalable means of completely recovering usable water from byproducts created by reverse...

Electric dewatering and drying of fine-grained products; Elektrisk afvanding og toerring af finkornede produkter

Energy Technology Data Exchange (ETDEWEB)

Hansen, H.K.; Villumsen, A.

2001-07-01

The aim of the project was to elucidate four aspects related to using electric direct current to find an energy saving alternative to existing methods within dewatering of fine-grained products. The four aspects were a) electrophoresis forced sedimentation of chalk slurry, b) electro osmotic dewatering of chalk slurry, c) electro osmotic dewatering of agricultural chalk and d) electro osmotic dewatering of liquid organic wastes. (EHS)

Electro-dewatering of wastewater sludge: influence of the operating conditions and their interactions effects.

Science.gov (United States)

Mahmoud, Akrama; Olivier, Jérémy; Vaxelaire, Jean; Hoadley, Andrew F A

2011-04-01

Electric field-assisted dewatering, also called electro-dewatering (EDW), is a technology in which a conventional dewatering mechanism such a pressure dewatering is combined with electrokinetic effects to realize an improved liquid/solids separation, to increase the final dry solids content and to accelerate the dewatering process with low energy consumption compared to thermal drying. The application of these additional fields can be applied to either or both dewatering stages (filtration and/or compression), or as a pre-or post-treatment of the dewatering process. In this study, the performance of the EDW on wastewater sludge was investigated. Experiments were carried out on a laboratory filtration/compression cell, provided with electrodes, in order to apply an electrical field. The chosen operating conditions pressure (200-1200 kPa) and voltage (10-50 V) are sufficient to remove a significant proportion of the water that cannot be removed using mechanical dewatering technologies alone. A response surface methodology (RSM) was used to evaluate the effects of the processing parameters of EDW on (i) the final dry solids content, which is a fundamental dewatering parameter and an excellent indicator of the extent of EDW and (ii) the energy consumption calculated for each additional mass of water removed. A two-factor central composite design was used to establish the optimum conditions for the EDW of wastewater sludge. Experiments showed that the use of an electric field combined with mechanical compression requires less than 10 and 25% of the theoretical thermal drying energy for the low and moderate voltages cases, respectively. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Flotation: A promising microalgae harvesting and dewatering technology for biofuels production.

Science.gov (United States)

Ndikubwimana, Theoneste; Chang, Jingyu; Xiao, Zongyuan; Shao, Wenyao; Zeng, Xianhai; Ng, I-Son; Lu, Yinghua

2016-03-01

Microalgal biomass as renewable energy source is believed to be of great potential for reliable and sustainable biofuels production. However, microalgal biomass production is pinned by harvesting and dewatering stage thus hindering the developing and growing microalgae biotechnology industries. Flotation technology applied in mineral industry could be potentially applied in microalgae harvesting and dewatering, however substantial knowledge on different flotation units is essential. This paper presents an overview on different flotation units as promising cost-effective technologies for microalgae harvesting thus bestowing for further research in development and commercialization of microalgae based biofuels. Dispersed air flotation was found to be less energy consuming. Moreover, Jameson cell flotation and dispersed ozone flotation are believed to be energy efficient microalgae flotation approaches. Microalgae harvesting and dewatering by flotation is still at embryonic stage, therefore extended studies with the focus on life cycle assessment, sustainability of the flotation unit, optimization of the operating parameters using different algal species is imperative. Though there are a number of challenges in microalgae harvesting and dewatering, with well designed and developed cultivation, harvesting/dewatering, extraction and conversion technologies, progressively, microalgae technology will be of great potential for biological carbon sequestration, biofuels and biochemicals production. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Thermal conductivity characteristics of dewatered sewage sludge by thermal hydrolysis reaction.

Science.gov (United States)

Song, Hyoung Woon; Park, Keum Joo; Han, Seong Kuk; Jung, Hee Suk

2014-12-01

The purpose of this study is to quantify the thermal conductivity of sewage sludge related to reaction temperature for the optimal design of a thermal hydrolysis reactor. We continuously quantified the thermal conductivity of dewatered sludge related to the reaction temperature. As the reaction temperature increased, the dewatered sludge is thermally liquefied under high temperature and pressure by the thermal hydrolysis reaction. Therefore, the bound water in the sludge cells comes out as free water, which changes the dewatered sludge from a solid phase to slurry in a liquid phase. As a result, the thermal conductivity of the sludge was more than 2.64 times lower than that of the water at 20. However, above 200, it became 0.704 W/m* degrees C, which is about 4% higher than that of water. As a result, the change in physical properties due to thermal hydrolysis appears to be an important factor for heat transfer efficiency. Implications: The thermal conductivity of dewatered sludge is an important factor the optimal design of a thermal hydrolysis reactor. The dewatered sludge is thermally liquefied under high temperature and pressure by the thermal hydrolysis reaction. The liquid phase slurry has a higher thermal conductivity than pure water.

Mechanical dewatering of silage; Mechanische Entwaesserung von Silage

Energy Technology Data Exchange (ETDEWEB)

Scholz, Volkhard; Daries, Werner [Leibniz-Institut fuer Agrartechnik Potsdam-Bornim e.V. (ATB), Potsdam (Germany). Abteilung Technik der Aufbereitung, Lagerung und Konservierung; Rinder, Ralf [Anhydro GmbH, Kassel (Germany)

2009-07-01

The use of screw presses for dewatering of silage is energetically more efficient than thermal drying. Tests with two types of screw presses show that on dry matter flow rates of more than 1.0 tDM/h the specific energy consumption is less than 30 kWh/tDM. The water content of the silage is decreased by 5 to 20 % and the share of undesired ingredients by 2 to 30 %. Besides press design and plant species, in particular moisture content, chip size and density of silage are essentially for the dewatering success. (orig.)

Pervaporation applied for dewatering of reaction mixture during esterification

OpenAIRE

Krasiński Andrzej; Wierzba Patrycja; Grudzień Agata; Hajmowicz Halina; Zawada Krzysztof; Synoradzki Ludwik

2016-01-01

In this work the esterification of diethyl tartrate was studied. The research was focused on the enhancement of reversible reaction yield, which is accomplished by dewatering of the reaction mixture. The removal of water shifts the equilibrium towards the main product. Pervaporation was applied for this purpose, and results were compared to distillation. The advantages and limitations of both processes are discussed. The experimental part consists of dewatering of mixture after the reaction h...

ENSINO-APRENDIZAGEM DE LÍNGUA ESTRANGEIRA IN-TANDEM PELA EAD: UMA PROPOSTA PARA ALUNOS INTERCAMBISTAS

OpenAIRE

Oliveira, Ana Amélia Furtado de; Rosário, Alex Donizeti do; Melo, Carina Adriele Duarte de; Moreira, Simone de Paula Teodoro; Souza, Wanderson Gomes de

2016-01-01

RESUMOEste trabalho tem como tema o ensino-aprendizagem de língua estrangeira pela modalidade Ead. Nos últimos anos, tem-se notado o crescimento da integração entre as instituições pertencentes à Acinnet, uma rede de cooperação educacional entre países como Argentina, Brasil, Chile e Paraguai. E uma das formas de integração ocorre por meio do intercâmbio entre os discentes. Essa pesquisa propõe-se a investigar estratégias metodológicas para o ensino-aprendizagem de língua estrangeira em Ead c...

Propagation of dust electro-acoustic modes in dusty plasma

International Nuclear Information System (INIS)

Avinash, K.

2001-01-01

The propagation of the dust electro-acoustic (DEA) mode in dusty plasma with different electron and ion temperatures T e and T i and different ion species is studied. The critical ratio of the dust space charge to the ion space charge ε for the excitation of DEA mode is found to decrease with increasing T e /T i and increase with m i /m e (m i and m e are the ion and electron masses). Thus experiments with hydrogen plasma where electrons are sufficiently hotter than ions and where the reduction in the dust charge with ε is more than 50% are essential for the observation of self-shielding and the DEA mode

Laboratory and field experience with rim ditch dewatering of MFT

Energy Technology Data Exchange (ETDEWEB)

Demoz, A.; Mikula, R. [Natural Resources Canada, Devon, AB (Canada). CANMET Western Research Centre; Lahaie, R. [Syncrude Canada Ltd., Edmonton, AB (Canada)

2010-07-01

This PowerPoint presentation described a rim ditch method of dewatering mature fine tailings (MFT). Polymer additions were used to strengthen the MFT and to decrease the capillary suction time (CST). Laboratory and field-scale studies were conducted to demonstrate the dewatering method. The flocculants were added in a Komax inline mixer. Polymers were then injected into the tailings. The mixing processes were optimized in a series of laboratory studies and then demonstrated in the field tests. The tests showed that CST and high dewatering rates were consistently maintained using the method. MFT feeds were also consistent. Release water quality was improved using the method. The large-scale test site is now being monitored for compliance with Directive 74. tabs., figs.

Electro-acoustic sensors based on AlN thin film: possibilities and limitations

Science.gov (United States)

Wingqvist, Gunilla

2011-06-01

The non-ferroelectric polar wurtzite aluminium nitride (AlN) material has been shown to have potential for various sensor applications both utilizing the piezoelectric effect directly for pressure sensors or indirectly for acoustic sensing of various physical, chemical and biochemical sensor applications. Especially, sputter deposited AlN thin films have played a central role for successful development of the thin film electro-acoustic technology. The development has been primarily driven by one device - the thin film bulk acoustic resonator (FBAR or TFBAR), with its primary use for high frequency filter applications for the telecom industry. AlN has been the dominating choice for commercial application due to compatibility with the integrated circuit technology, low acoustic and dielectric losses, high acoustic velocity in combination with comparably high (but still for some applications limited) electromechanical coupling. Recently, increased piezoelectric properties (and also electromechanical coupling) in the AlN through the alloying with scandium nitride (ScN) have been identified both experimentally and theoretically. Inhere, the utilization of piezoelectricity in electro-acoustic sensing will be discussed together with expectation on acoustic FBAR sensor performance with variation in piezoelectric material properties in the parameter space around AlN due to alloying, in view of the ScxAl1-xN (0

Osmotic Effects in Sludge Dewatering

DEFF Research Database (Denmark)

Keiding, Kristian; Rasmussen, Michael R.

2003-01-01

A model of filtration dewatering is presented. The model is based on the d’Arcy flow equation in which the resistance to filtration is described by the Corzeny–Carman equation and the driving force is the difference between the external pressure and the osmotic pressure of the filter cake. It has...

Co-conditioning and dewatering of chemical sludge and waste activated sludge.

Science.gov (United States)

Chang, G R; Liu, J C; Lee, D J

2001-03-01

The conditioning and dewatering behaviors of chemical and waste activated sludges from a tannery were studied. Capillary suction time (CST), specific resistance to filtration (SRF), and bound water content were used to evaluate the sludge dewatering behaviors. Zeta potentials were also measured. Experiments were conducted on each sludge conditioned and dewatered separately, and on the sludge mixed at various ratios. Results indicate that the chemical sludge was relatively difficult to be dewatered, even in the presence of polyelectrolyte. When the waste activated sludge was mixed with the chemical sludge at ratios of 1:1 and 2:1, respectively, the dewaterability of chemical sludge improved remarkably while the relatively better dewaterability of the waste activated sludge deteriorated only to a limited extent. As the mixing ratios became 4:1 and 8:1, the dewaterability of the mixed sludge was equal to that of the waste activated sludge. The optimal polyelectrolyte dosage for the mixed sludge was equal to or less than that of the waste activated sludge. It is proposed that the chemical sludges act as skeleton builders that reduce the compressibility of the mixed sludge whose dewaterability is enhanced. Bound water contents of sludge decreased at low polyelectrolyte dosage and were not significantly affected as polyelectrolyte dosage increased. Advantages and disadvantages of co-conditioning and dewatering chemical sludge and waste activated sludge were discussed.

46 CFR 28.255 - Bilge pumps, bilge piping, and dewatering systems.

Science.gov (United States)

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Bilge pumps, bilge piping, and dewatering systems. 28... the Aleutian Trade § 28.255 Bilge pumps, bilge piping, and dewatering systems. (a) Each vessel must be equipped with a bilge pump and bilge piping capable of draining any watertight compartment, other than...

Synthesis, characterization, and secondary sludge dewatering performance of a novel combined silicon–aluminum–iron–starch flocculant

Energy Technology Data Exchange (ETDEWEB)

Lin, Qintie, E-mail: qintlin@163.com; Peng, Huanlong; Zhong, Songxiong; Xiang, Jiangxin

2015-03-21

Highlights: • Silicon, aluminum, and iron were grafted onto starch chains to synthesize CSiAFS. • The sludge dewatering performance of CSiAFS was superior to PAC, PAM, and FeCl{sub 3}. • CSiAFS exhibited a good dewatering efficiency over a wide range of pH (3.0–11.0). • CSiAFS had a discontinuous surface with channels which helped to sludge dewatering. - Abstract: Flocculation is one of the most widely used cost-effective pretreatment method for sludge dewatering, and a novel environmentally friendly and efficient flocculant is highly desired in the sludge dewatering field. In this study, a novel combined silicon–aluminum–ferric–starch was synthesized by grafting silicon, aluminum, and iron onto a starch backbone. The synthesized starch flocculant was characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy, X-ray powder diffraction, and thermogravimetric analysis. The dewatering performance of secondary sludge was evaluated according to the capillary suction time, settling volume percentage, and specific resistance to filtration. The results indicated that the copolymer exhibited: (1) a good dewatering efficiency over a wide pH range of 3.0–11.0, (2) superior sludge dewatering performance compared to those of polyaluminum chloride (PACl), polyacrylamide (PAM), ferric chloride, and (3) a discontinuous surface with many channels or voids that helps to mobilize the impermeable thin layer of secondary sludge during filter pressing. Such a novel copolymer is a promising green flocculant for secondary sludge dewatering applications.

Atomistic Structure of Mineral Nano-aggregates from Simulated Compaction and Dewatering.

Science.gov (United States)

Ho, Tuan Anh; Greathouse, Jeffery A; Wang, Yifeng; Criscenti, Louise J

2017-11-10

The porosity of clay aggregates is an important property governing chemical reactions and fluid flow in low-permeability geologic formations and clay-based engineered barrier systems. Pore spaces in clays include interlayer and interparticle pores. Under compaction and dewatering, the size and geometry of such pore spaces may vary significantly (sub-nanometer to microns) depending on ambient physical and chemical conditions. Here we report a molecular dynamics simulation method to construct a complex and realistic clay-like nanoparticle aggregate with interparticle pores and grain boundaries. The model structure is then used to investigate the effect of dewatering and water content on micro-porosity of the aggregates. The results suggest that slow dewatering would create more compact aggregates compared to fast dewatering. Furthermore, the amount of water present in the aggregates strongly affects the particle-particle interactions and hence the aggregate structure. Detailed analyses of particle-particle and water-particle interactions provide a molecular-scale view of porosity and texture development of the aggregates. The simulation method developed here may also aid in modeling the synthesis of nanostructured materials through self-assembly of nanoparticles.

Effect of hydrothermal dewatering on the slurryability of brown coals

International Nuclear Information System (INIS)

Yu Yujie; Liu Jianzhong; Wang Ruikun; Zhou Junhu; Cen Kefa

2012-01-01

Highlights: ► Brown coals are upgraded by hydrothermal dewatering. ► The moisture content and oxygen functional groups decrease during the process. ► The point of zero charge and the contact angle rise as the temperature increases. ► The products were highly hydrophobic. ► The improvement on slurryability of solid products were examined. - Abstract: Two brown coals from China were dewatered under hydrothermal dewatering (HTD) conditions at 250–320 °C for 1 h in a 2 L autoclave. The hydrothermally dewatered products were used to prepare coal water slurry (CWS) with a lower viscosity than brown raw coal slurry. Moreover, the coal rank and heat value of the brown coal increased as the inherent moisture and oxygen content decreased during the HTD process. The maximum solid concentration of CWS prepared from XiMeng coal increased from 45.7% to 59.3%, whereas that of CWS prepared from BaoTou coal increased from 53.7% to 62.1%, after being dewatered at 320 °C. The improvement in the slurryability of brown coal significantly depended on the final temperature of the HTD process, the mechanism of which can be explained by the chemical analysis of oxygen functional groups, zeta potential, and the contact angle of the surface between coal and water. The oxygen functional groups, the oxygen/carbon ratio and hydrogen/carbon ratio in brown coal decreased, indicating that the coal rank was upgraded during the HTD process. As a result, both the point of zero charge and the contact angle increased, implying that the HTD products were highly hydrophobic.

Dewatering of planned Key Lake open pits in northern Saskatchewan

International Nuclear Information System (INIS)

Unland, W.; Holl, N.

1980-01-01

The engineering design and experience gained so far with a dewatering system for an open-pit uranium mine planned at Key Lake in Northern Saskatchewan are presented. An extensive unconfined overburden aquifer is hydraulically connected with the underlying Athabasca Formation and basement rocks, both of relatively low hydraulic conductivity. The overburden aquifer is embedded in a bedrock trough, with the deepest depression between the planned pits. Hydrogeological data were used in a numerical dewatering model simulating groundwater flow at different stages of the pit development. Based on the model results, the enginering design had to provide for different pumping rates, varying between 1.0 and 0.21 m 3 /sec. This problem was solved by using a double line pressure system. The design concept for the complete peripheral discharge system and the well design used for 26 dewatering wells are discussed. (auth)

Centrifuge - dewatering of oil sand fluid tailings: phase 2 field-scale test

Energy Technology Data Exchange (ETDEWEB)

Seto, Jack T.C. [BGC Engineering Inc (Canada); O' Kane, Mike [O' Kane Consultants Inc (Canada); Donahue, Robert [Applied Geochemical Solutions Engineering (Canada); Lahaie, Rick [Syncrude Canada Ltd (Canada)

2011-07-01

In order to reduce the accumulation of oil sand fluid fine tailings (FFT) and to create trafficable surfaces for reclamation, Syncrude Canada Ltd. has been studying several tailings technologies. Centrifuge-dewatering is one such technology. This paper discusses the phase 2 field-scale tests for centrifuge-dewatering of oil sand FFT. In centrifuge-dewatering, FFT is diluted and treated with flocculant, then processed through a centrifuge plant and the high-density underflow is transported to a tailings deposit. This technology has evolved since 2005 from laboratory bench scale tests. More than 10,000 cubic meters of centrifuge cake was treated, produced and transported to ten different deposits over a 12-week period from August to October 2010. The amount of solids in FFT was increased from 30% to 50% by centrifuging. Sampled deposits were tested and instrumented for in situ strength. It can be concluded that the deposits can be strengthened and densified by natural dewatering processes like freeze-thaw action and evaporative drying.

Field performance of de-watered fluid fine tailings for oil sands reclamation

Energy Technology Data Exchange (ETDEWEB)

Ward Wilson, G.; Kabwe, Louis [University of Alberta (Canada); Donahue, Robert [Applied Geochemical Engineering Inc. (Canada); Lahaie, Rick [Syncrude Canada Ltd (Canada)

2011-07-01

This document presents research carried out by Syncrude Canada Ltd and its partners to evaluate several methods of de-watering fluid fine tailings to increase the solids content and at the same time produce a tailings profile which will permit final reclamation. Several de-watering methods are discussed in this paper, particularly in-line flocculation and centrifuged fluid fine tailings. First, in-line flocculation with organic polymers is discussed followed by thin left deposition, then the flocculation and centrifugation process to produce a paste- like material that is deposited in a thicker layer is presented. This document details the preliminary performance of both discussed methods; extensive instrumentation was used to measure de-watering rates due to consolidation, atmospheric drying, downward drainage to the foundation materials, and freeze/thaw consolidation. Finally, a summary of the measured results of de-watering rates and numerical model results obtained from the SoilCover model are presented and discussed.

EADS-ST's Latest Bipropellant 10N Thruster and 400 N Engine: The Fully European Solution

Science.gov (United States)

Fick, M.; Dreer, T.; Gotzig, U.; Schulte, G.; Bachmann, J.; Lagier, F.; Benoit, E.

2004-10-01

Increasing restrictions, complications and bureaucratic hurdles for obtaining export licenses from the US government for American components to be used on certain projects and for certain launch sites or end customers, required the development of new or upgraded European flow control valves to guarantee an independent and unrestricted marketing of EADS-ST's orbital propulsion products to commercial customers worldwide. The development and qualification of the European flow control valves for EADS-ST's 10 N bipropellant thruster and 400 N bipropellant engine is highlighted, together with verification tests and the qualification programs at engine level. The 400 N engine under qualification with the new valves is an enhanced version with an increased area ratio of the nozzle.

METODE PELAKSANAAN DEWATERING YANG RAMAH LINGKUNGAN PADA PROYEK THE NEST CONDOTEL

Directory of Open Access Journals (Sweden)

I Wayan Intara

2016-03-01

Full Text Available Proyek Pembangunan The Nest Condotel merupakan salah satu upaya untuk memenuhi sarana dan prasarana pariwisata khusunya daerah Nusa Dua-Bali. Proyek ini dibangun di tengah-tengah pemukiman penduduk dan berdekatan dengan Pengolahan Limbah BTDC. Setelah dilaksanakan survei lapangan ada permasalahan yang dihadapi pada pembangunan proyek ini yaitu pada pengerjaan struktur basement. Kondisi muka air tanah lebih tinggi daripada rencana pemukaan galian lantai basement yang akan dibuat. Di samping itu, kondisi tanah yang kurang baik dengan kondisi tanah yang berpasir. Berdasarkan permasalahan di atas perlu adanya pemilihan perencanaan metode penanganan muka air tanah yang paling tepat dalam pekerjaan  galian basement. Dewatering adalah proses penurunan muka air tanah pada suatu area tertentu dengan cara pemompaan dari sebuah sumur ataupun saluran. Tujuannya adalah untuk menjaga area galian tetap kering dalam proses konstruksi dan menjaga kestabilan lereng galian. Pemompaan dilakukan melalui sumur-sumur dewatering (dewatering well atau well point atau saluran-saluran (sump dengan menggunakan pompa submersible (submersible pump. Dengan demikian penggalian basement bisa dikerjakan dengan baik. Penelitian ini adalah menentukan metode pelaksanaan pekerjaan dewatering yang paling tepat dari metode-metode pelaksanaan yang mungkin untuk dilaksankan berdasarkan biaya, waktu, dan dampak terhadap lingkungan. Metodelogi yang digunakan untuk analisis data adalah menganalisis metode-metode pelaksanaan yang ada dan dari hasil analisis akan ditetapkan metode pelaksanaan terbaik. Hasil analisis dari beberapa metode pelaksanaan yang ada untuk pekerjaan dewatering digunakan adalah predrainage dan open pumping, metode yang terpilih yaitu open pumping adalah metode terbaik untuk dilaksanakan pada proyek tersebut dengan biaya yang terendah, waktu pelaksanaan yang lebih cepat, dan dampak lingkungan yang dapat diminimalisir

Dewatering of Yoghurt Using Permeable Membrane and Acrylic Superabsorbent Hydrogel

Directory of Open Access Journals (Sweden)

A. Ahmadpour

2008-02-01

Full Text Available Conventional processes of food dewatering, such as thermal, have undesirable and destruction effects on vitamins, aromatic compounds and pigments. In addition, they are accompanied with some technological complications and energy consumption. Thus, food concentration processes are directed to non-thermal techniques or methods with reduced heat effects. Superabsorbents are highly hydrophilic polymer networks which can absorb water and aqueous solutions some hundred times of their weights and retain them. These materials are subgroups of hydrogel family that are transformed into gels after absorbing water. In the present research, the possibilities of yoghurt dewatering using superabsorbents have been investigated for the first time in Iran and some remarkable results are obtained for this vital product. In the experiments carried out to investigate the effect of these absorbents on normal method of yoghurt concentration (use of permeable membrane, type of bed (wide and vertical and time are also studied. The percentage of total soluble solids and dry solids of dewatered samples were measured in different time intervals up to 180 min. The results showed that superabsorbent on a wide bed would reduce the concentration time to one third. In other words, in a certain time interval, more than 70% increase in yoghurt dry solids was observed compared to normal method. These results show that acrylic superabsorbent hydrogel can be applied as highly hydrophilic material in non-thermal food dewatering methods.

Electroacoustic isoelectric point determinations of bauxite refinery residues: different neutralization techniques and minor mineral effects.

Science.gov (United States)

Freire, Tiago S S; Clark, Malcolm W; Comarmond, M Josick; Payne, Timothy E; Reichelt-Brushett, Amanda J; Thorogood, Gordon J

2012-08-14

Bauxite refinery residue (BRR) is a highly caustic, iron hydroxide-rich byproduct from alumina production. Some chemical treatments of BRR reduce soluble alkalinity and lower residue pH (to values work shows that minor mineral components in complex mineral systems may have a disproportionate effect on the observable bulk IEP. Furthermore, this work shows the appropriateness of electroacoustic techniques in investigating samples with significant soluble mineral components (e.g., ANC).

Pressurised electro-osmotic dewatering of activated and anaerobically digested sludges: electrical variables analysis.

Science.gov (United States)

Citeau, M; Olivier, J; Mahmoud, A; Vaxelaire, J; Larue, O; Vorobiev, E

2012-09-15

Pressurised electro-osmotic dewatering (PEOD) of two sewage sludges (activated and anaerobically digested) was studied under constant electric current (C.C.) and constant voltage (C.V.) with a laboratory chamber simulating closely an industrial filter. The influence of sludge characteristics, process parameters, and electrode/filter cloth position was investigated. The next parameters were tested: 40 and 80 A/m², 20, 30, and 50 V-for digested sludge dewatering; and 20, 40 and 80 A/m², 20, 30, and 50 V-for activated sludge dewatering. Effects of filter cloth electric resistance and initial cake thickness were also investigated. The application of PEOD provides a gain of 12 points of dry solids content for the digested sludge (47.0% w/w) and for the activated sludge (31.7% w/w). In PEOD processed at C.C. or at C.V., the dewatering flow rate was similar for the same electric field intensity. In C.C. mode, both the electric resistance of cake and voltage increase, causing a temperature rise by ohmic effect. In C.V. mode, a current intensity peak was observed in the earlier dewatering period. Applying at first a constant current and later on a constant voltage, permitted to have better control of ohmic heating effect. The dewatering rate was not significantly affected by the presence of filter cloth on electrodes, but the use of a thin filter cloth reduced remarkably the energy consumption compared to a thicker one: 69% of reduction energy input at 45% w/w of dry solids content. The reduction of the initial cake thickness is advantageous to increase the final dry solids content. Copyright © 2012 Elsevier Ltd. All rights reserved.

Characterization and dewatering of flotation technological tailings

Directory of Open Access Journals (Sweden)

Grigorova I.

2014-01-01

Full Text Available The treatment of flotation tailings is today a subject of interest in mineral processing because of the potential of wasted materials as an actual mineral resource and because of environmental reasons. Decantation ponds are found at almost every mine in the world. They are large earth fill dams containing the residue of the milling process to extract metals from mined ores. Traditional wet tailings disposal has been problematic due to the risk of ground water contamination and the difficulty in rehabilitating storage sites. Tailings dams are at risk of failure due to leakage, instability, liquefaction, and poor design. In the last few years the use of paste technology in the disposal of mine tailings is increasingly studied as an option to conventional tailings dams. The Lucky Invest Concentrator is located in the Eastern Rhodopes Mountain of Bulgaria. Since 1959 lead-zinc ores are dressed. Finally, during the flotation cycle lead and zinc concentrates are produced. The final technological processing waste precipitates in tailing pond. Research and development program has started to established opportunities to obtain dry deposit of the ore processing residue and analyses the feature of new tailing disposal method. The tailings particle size distributions and chemical compositions were determined. The data from laboratory and pilot scale tests clearly illustrate that there are the possibilities to obtaine lead-zinc dewatered tailings. The experimental results show that new cyclone modifications have a potential in dewatering technology of flotation tailings. It appears that dewatering cyclones can be an approach on new tailings pond elimination technology.

Influence of nanoparticles on the polymer-conditioned dewatering of wastewater sludges.

Science.gov (United States)

Boyle, N J; Evans, G M

2013-01-01

The effect of using small-scale, high surface area, nanoparticles to supplement polymer-conditioned wastewater sludge dewatering was investigated. Aerobically digested sludge and waste activated sludge sourced from the Hunter Valley, NSW, Australia, were tested with titanium dioxide nanoparticles. The sludge samples were dosed with the nanoparticles in an attempt to adsorb a component of the charged biopolymer surfactants present naturally in sludge. The sludge was conditioned with a cationic polymer. The dewatering characteristics were assessed by measuring the specific resistance to filtration through a modified time-to-filter testing apparatus. The solids content of the dosed samples was determined by a mass balance and compared to the original solids content in the activated sludge. Test results indicated that nanoparticle addition modified the structure of the sludge and provided benefits in terms of the dewatering rate. The samples dosed with nanoparticles exhibited faster water removal, indicating a more permeable filter cake and hence more permeable sludge. A concentration of 2-4% nanoparticles was required to achieve a noticeable benefit. As a comparison, the sludge samples were also tested with a larger particle size, powdered activated carbon (PAC). It was found that the PAC did provide some minor benefits to sludge dewatering but was outperformed by the nanoparticles. The solids content of the final sludge was increased by a maximum of up to 0.6%. The impact of the order sequence of particles and polymer was also investigated. It was found that nanoparticles added before polymer addition provided the best dewatering performance. This outcome was consistent with current theories and previous research through the literature. An economic analysis was undertaken to confirm the viability of the technology for implementation at a full-scale plant. It was found that, currently, this technology is unlikely to be favourable unless the nanoparticles can be

Application of a thermally assisted mechanical dewatering process to biomass

Energy Technology Data Exchange (ETDEWEB)

Mahmoud, A.; Arlabosse, P. [Universite de Toulouse, Mines Albi, CNRS, Campus Jarlard, F-81013 Albi cedex 09 (France); Ecole des Mines Albi, Centre RAPSODEE, Campus Jarlard, F-81013 Albi (France); Fernandez, A. [Universite de Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31400 Toulouse (France); INRA, UMR792 Ingenierie des Systemes Biologiques et des Procedes, CNRS, UMR5504, F-31400 Toulouse (France)

2011-01-15

Thermally assisted mechanical dewatering (TAMD) is a new process for energy-efficient liquid/solids separation which enhances conventional-device efficiency. The main idea of this process is to supply a flow of heat in mechanical dewatering processes to favour the reduction of the liquid content. This is not a new idea but the proposed combination, especially the chosen operating conditions (T < 100 C and P < 3000 kPa) constitutes an original approach and a significant energy saving since the liquid is kept in liquid state. Response surface methodology was used to evaluate the effects of the processing parameters of TAMD on the final dry solids content, which is a fundamental dewatering parameter and an excellent indicator of the extent of TAMD. In this study, a two-factor central composite design was used to establish the optimum conditions for the TAMD of alfalfa biomass. Experiments were carried out on a laboratory compression cell. Experiments showed that the dewatering enhancement results only from thermal effects. With a moderate heat supply (T{sub piston} = 80 C), the dry solid content of the press cake can reach 66%, compared to 36% at ambient temperature. A significant regression model, describing changes on final dry solids content with respect to independent variables, was established with determination coefficient, R{sup 2}, greater than 88%. With an energy consumption of less than 150 kWh/m{sup 3}, the use of the TAMD process before a thermal drying process leads to an energy saving of at least 30% on the overall separation chain. (author)

Confirmatory/release survey of the property at 71 Pearce Avenue (Former EAD Building) in Tonawanda, New York

Energy Technology Data Exchange (ETDEWEB)

Salame-Alfie, A.; Alibozek, R. [New York Dept. of Health, Albany, NY (United States)

1995-12-31

EAD Metallurgical, Inc., operated a facility in Tonawanda, New York, in which it utilized Americium 241 (Am-241) for the production of foil sources for use in smoke detectors. EAD was in operation between 1977 and 1983. By 1983, the company started losing money, and decided to relocate to Mexico. Before closing down its Tonawanda operation, however, it was required by the New York State Department of Labor (DOL) to decontaminate its facility to limits specified by DOL. No records of discharges to the sewer system were kept during this decontamination effort. Unsuccessful decontamination efforts by several EAD employees and contractors left the building contaminated, in particular the concrete floors and walls. To determine the scope of work for the decontamination project, staff from the New York State Departments of Health (DOH) and Environmental Conservation (DEC) conducted a Characterization Survey of the facility in 1993. This survey identified contamination levels of Am-241 in excess of release limits throughout the building, in the soil outside the facility, in pipes for sewage and interior drainage, and in an 8 x 8 x 11 foot sump pit in the building. DOH issued a request for proposals in early 1994 for the decontamination and subsequent decommissioning of the former EAD building, and NES/IES Inc. (NES) was awarded the contract to perform the remediation. DOH`s assignment was to provide an on-site presence to insure the completion of all agreed upon tasks, according to the terms of the contract and work plans submitted by NES. Additionally, the DOH staff acted as a liaison between NES, DOH, DEC and DOL central offices to review, comment and approve all changes or modifications to NES`s approach to the decontamination efforts. The assigned staff was also responsible for conducting confirmatory sampling and surveys of all areas deemed releasable to DOL and DEC criteria by NES.

Electroosmotically enhanced dewatering/deliquoring of fine-particle coal: Final report, January 1--December 31, 1988

Energy Technology Data Exchange (ETDEWEB)

Sami, Sedat [Department of Civil Engineering and Mechanics, Southern Illinois Univ., Carbondale, IL (United States); Davis, Philip K. [Department of Civil Engineering and Mechanics, Southern Illinois Univ., Carbondale, IL (United States); Smith, James G. [Department of Electrical Engineering, Southern Illinois Univ., Carbondale, IL (United States)

1989-03-01

This research is an investigation of the use of electroosmosis to dewater/deliquor ultrafine coal. Post-beneficiation dewatering/deliquoring methods for ultrafine coal are inadequate and generally require subsequent thermal drying. Thermal drying is not only expensive and time consuming, it also does not recover liquids for reuse in beneficiation processes. The degree of difficulty associated with dewatering increases as surface forces become more important than gravimetric forces. Electroosmotic flow has advantages for dewatering because it is much less sensitive to pore size than hydraulic gradient flow for the 1 to 75 ..mu..m ultrafine size range. The first year of this project focused upon preparation of ultrafine coal samples, development of test equipment and test cells, identification of variables affecting electroosmosis, and trial runs. Techniques and procedures not previously used by researchers of electroosmotic dewatering have revealed important information about the dynamics of the electroosmosis process. The identification of the first few millimeters of the cathode region of the cell as the sink for most of the energy input into the process provides the potential for improving efficiency by concentrating the second year effort on intervention in that region. Information gathered about differences in FTIR spectra as a function of location in the dewatering cell will be investigated. Changes in pH with temperature and by the application of electroosmotic current flow will receive attention, as well. 178 refs., 16 figs.

Modelling dewatering behaviour through an understanding of solids formation processes. Part II--solids separation considerations.

Science.gov (United States)

Dustan, A C; Cohen, B; Petrie, J G

2005-05-30

An understanding of the mechanisms which control solids formation can provide information on the characteristics of the solids which are formed. The nature of the solids formed in turn impacts on dewatering behaviour. The 'upstream' solids formation determines a set of suspension characteristics: solids concentration, particle size distribution, solution ionic strength and electrostatic surface potential. These characteristics together define the suspension's rheological properties. However, the complicated interdependence of these has precluded the prediction of suspension rheology from such a fundamental description of suspension characteristics. Recent shear yield stress models, applied in this study to compressive yield, significantly reduce the empiricism required for the description of compressive rheology. Suspension compressibility and permeability uniquely define the dewatering behaviour, described in terms of settling, filtration and mechanical expression. These modes of dewatering may be described in terms of the same fundamental suspension mechanics model. In this way, it is possible to link dynamically the processes of solids formation and dewatering of the resultant suspension. This, ultimately, opens the door to improved operability of these processes. In part I of this paper we introduced an integrated system model for solids formation and dewatering. This model was demonstrated for the upstream processes using experimental data. In this current paper models of colloidal interactions and dewatering are presented and compared to experimental results from batch filtration tests. A novel approach to predicting suspension compressibility and permeability using a single test configuration is presented and tested.

Ultra scale-down device to predict dewatering levels of solids recovered in a continuous scroll decanter centrifuge.

Science.gov (United States)

Lopes, A G; Keshavarz-Moore, E

2013-01-01

During centrifugation operation, the major challenge in the recovery of extracellular proteins is the removal of the maximum liquid entrapped within the spaces between the settled solids-dewatering level. The ability of the scroll decanter centrifuge (SDC) to process continuously large amounts of feed material with high concentration of solids without the need for resuspension of feeds, and also to achieve relatively high dewatering, could be of great benefit for future use in the biopharmaceutical industry. However, for reliable prediction of dewatering in such a centrifuge, tests using the same kind of equipment at pilot-scale are required, which are time consuming and costly. To alleviate the need of pilot-scale trials, a novel USD device, with reduced amounts of feed (2 mL) and to be used in the laboratory, was developed to predict the dewatering levels of a SDC. To verify USD device, dewatering levels achieved were plotted against equivalent compression (Gtcomp ) and decanting (Gtdec ) times, obtained from scroll rates and feed flow rates operated at pilot-scale, respectively. The USD device was able to successfully match dewatering trends of the pilot-scale as a function of both Gtcomp and Gtdec , particularly for high cell density feeds, hence accounting for all key variables that influenced dewatering in a SDC. In addition, it accurately mimicked the maximum dewatering performance of the pilot-scale equipment. Therefore the USD device has the potential to be a useful tool at early stages of process development to gather performance data in the laboratory thus minimizing lengthy and costly runs with pilot-scale SDC. © 2013 American Institute of Chemical Engineers.

A new dewatering technique for stingless bees honey

Directory of Open Access Journals (Sweden)

Ramli Ahmad Syazwan

2017-01-01

Full Text Available One of the problems faced in stingless bee honey storage is spoilage by the fermentation process occurs in honey due to its high water content. There are a few techniques available currently, but they are time consuming and there is excessive heat involved in the process. The temperature of the process must be kept low because excessive heat can deteriorate nutrition value and biochemical content in honey. Hence, a new method of honey dewatering was developed using a Low Temperature Vacuum Drying (LTVD with induced nucleation technique.The objective of this research is to investigate the performance of a LTVD with induced nucleation to reduce the water content in honey. First, the honey was placed in a pressure vessel, and then air was removed. Then, the honey was slightly heated at 30°C and the water content before and after the experiment was measured by a refractometer. The steps were repeated until the water content reached below 20%. It was found that the LTVD method improved the water removal rate significantly with an average of 0.15% of water content per minute. That is 3 times much faster than the conventional method of low temperature heating by Tabouret. Higher temperature during dewatering process improved the dewatering rate significantly. It can be concluded that LTVD is a promising option in tackling the high water content in stingless bee honey issue.

105-N Fuel Storage Basin dewatering conceptual plan

International Nuclear Information System (INIS)

Schilperoort, D.L.

1996-11-01

This conceptual plan discusses the processes that will be used for draining and disposing of water from the 105-N Fuel Storage Basin (N Basin), and includes a description of the activities to control surface contamination and potential high dose rates encountered during dewatering. The 105-N Fuel Storage Basin is located in the 100-N Area of the Hanford Site in Richland, Washington. The processes for water disposal include water filtration, water sampling and analysis, tanker loading and unloading, surface decontamination and sealing, and clean out and disposal of residual debris and sediments during final pumping to remove the N Basin water. Water disposal is critical for the deactivation of N Reactor. A Memorandum of Understanding (MOU) between the US Department of Energy (DOE) Environmental Restoration (ER) Program and DOE Waste Management (WM) Program establishes the 200 East Effluent Treatment Facility (ETF) as the final treatment and disposal site for N Basin water and identifies pre-treatment requirements. This MOU states that water delivery will be completed no later than October 31, 1996, and will require a revision due to the current de-watering schedule date. The current MOU requires four micron filtration prior to shipment to ETF. The MOU revision for delivery date extension seeks to have the filtration limit increased to five microns, which eliminates the need for a second filter system and simplifies dewatering. For the purposes of this plan, it will be assumed that five micron filtration will be used

Influence of process operating parameters on dryness level and energy saving during wastewater sludge electro-dewatering.

Science.gov (United States)

Mahmoud, Akrama; Hoadley, Andrew F A; Conrardy, Jean-Baptiste; Olivier, Jérémy; Vaxelaire, Jean

2016-10-15

Electrically assisted mechanical dewatering, known as electro-dewatering (EDW), is an alternative emerging technology for energy-efficient liquid/solids separation in the dewatering of wastewater sludge. In this study, the performance of the electro-dewatering (EDW) process for activated wastewater sludge was investigated. The influence of the operating modes; being the timing of voltage (U-EDW) or current (I-EDW) application to either or both the filtration and compression stages, and the influence of the applied pressure (in successive 30 min pressure steps) were studied. The results showed that by delaying the application of the electric field to the filter cake compression stage, there was a potential saving in power consumption of around 10-12% in the case of U-EDW and about 30-46% in the case of I-EDW. The increase of the applied pressure from 0.5 to 12 bar during the filter cake compression stage leads to an increase in electro-dewatering kinetics. The results also reveal that at a low electric field level the increase of the processing pressure has a relatively pronounced effect on the dewatering process. At high levels of the electric field, a minimum processing pressure (4-6 bar) is required to improve the electrical contact between the electrode and the sludge and thus lower the energy consumption. Copyright © 2016 Elsevier Ltd. All rights reserved.

Electroacoustic control of Rijke tube instability

Science.gov (United States)

Zhang, Yumin; Huang, Lixi

2017-11-01

Unsteady heat release coupled with pressure fluctuation triggers the thermoacoustic instability which may damage a combustion chamber severely. This study demonstrates an electroacoustic control approach of suppressing the thermoacoustic instability in a Rijke tube by altering the wall boundary condition. An electrically shunted loudspeaker driver device is connected as a side-branch to the main tube via a small aperture. Tests in an impedance tube show that this device has sound absorption coefficient up to 40% under normal incidence from 100 Hz to 400 Hz, namely over two octaves. Experimental result demonstrates that such a broadband acoustic performance can effectively eliminate the Rijke-tube instability from 94 Hz to 378 Hz (when the tube length varies from 1.8 m to 0.9 m, the first mode frequency for the former is 94 Hz and the second mode frequency for the latter is 378 Hz). Theoretical investigation reveals that the devices act as a damper draining out sound energy through a tiny hole to eliminate the instability. Finally, it is also estimated based on the experimental data that small amount of sound energy is actually absorbed when the system undergoes a transition from the unstable to stable state if the contrpaol is activated. When the system is actually stabilized, no sound is radiated so no sound energy needs to be absorbed by the control device.

Limites e possibilidades do ensino à distância (EaD na educação permanente em saúde: revisão integrativa

Directory of Open Access Journals (Sweden)

Adriane das Neves Silva

2015-04-01

Full Text Available Trata-se de um estudo sobre o uso do ensino a distância (EaD como uma estratégia de ensino na educação permanente em saúde (EPS, que teve como objetivo identificar e analisar os limites e possibilidades do uso da EaD na EPS. Estudo de revisão integrativa. O resultado aponta que a EaD é uma estratégia inovadora possível e potencial para a EPS, facilitando o desenvolvimento da aprendizagem dentro ou fora da instituição de saúde, porém é evidente a escassez de pesquisas na área. As limitações para a realização dos programas estão relacionadas à variável tempo, preparação para lidar com as tecnologias e importância do tutor como facilitador da aprendizagem. Conclui-se que o uso da EaD tem tido uma importante contribuição para o desenvolvimento dos recursos humanos em saúde, seja no processo de formação e/ou no processo contínuo de conhecimento.

Dewatering behaviour of ultrafine hard coal particles

Energy Technology Data Exchange (ETDEWEB)

Fischer, D.; Alizadeh, A.; Simonis, W.

1986-03-01

With decreasing particle diameter distribution the dewatering behaviour of coal gets increasingly complicated. A correlation between final moisture and content of particles below 25..mu..m in the course of centrifuging can be verified. This behaviour of the particles below 25..mu..m can be explained by the great specific surface, on the one hand, and by the distribution of the surface charge density, on the other hand. The charge density depends on the type of coal, on the minerals content and their make-up, as well as on the characteristics of the surrounding medium. The surface charge can be measured indirectly. Varying electrophoretic mobilities of the particles are observed in dependence on the type of raw material. In the neutral pH-range, minerals have a negative surface charge, while coal has a positive one. By way of adding reagents it is possible to invert the negative charges with complicated dewatering characteristics into positive charges. A similar influence will be exerted by changing the pH-value. 6 references.

Reconstitution of dewatered food processing residuals with manure to increase energy production from anaerobic digestion

International Nuclear Information System (INIS)

Wall, David M.; Wu-Haan, Wei; Safferman, Steven I.

2012-01-01

Solid residuals generated from dewatering food processing wastewater contain organic carbon that can potentially be reclaimed for energy through anaerobic digestion. This results in the diversion of waste from a landfill and uses it for a beneficial purpose. Dewatering the waste concentrates the carbon, reducing transportation costs to a farm digester where it can be blended with manure to increase biogas yield. Polymers are often used in the dewatering of the food waste but little is known regarding their impact on biogas production. Four 2 dm 3 working volume, semi-continuous reactors, were used at a mesophilic temperature and a solids retention time (SRT) of 15 days. Reactors were fed daily with a blended feedstock containing a food processing sludge waste (FPSW)/manure ratio of 2.2:1 (by weight) as this produced the optimized carbon to nitrogen ratio. Results demonstrated that reconstitution of dewatered FPSW with dairy manure produced approximately 2 times more methane than animal manure alone for the same volume. However, only approximately 30% of volatile solids (VS) were consumed indicating energy potential still remained. Further, the efficiency of the conversion of VS to methane for the blended FPSW/manure was substantially less than for manure only. However, the overall result is an increase in energy production for a given tank volume, which can decrease life cycle costs. Because all FPSW is unique and the determination of dewatering additives is customized based on laboratory testing and field adjustment, generalizations are difficult and specific testing is required. -- Highlights: ► Energy production in anaerobic digestion can increase by co-blending food waste. ► Energy for transporting food waste to blend with manure is less when dewatered. ► Dewatered food waste in manure produced twice as much methane than manure. ► Efficiency of carbon to methane was low because of ammonium bicarbonate production. ► Carbon destruction was 30%, more

An experimental investigation of microalgal dewatering efficiency of belt filter system

Directory of Open Access Journals (Sweden)

Anjali Sandip

2015-11-01

Full Text Available The objective of this study was to investigate the microalgal dewatering efficiency of a belt filter system for feed concentrations below 10 g dry wt./L. A prototype belt filtration system designed for 50 g dry wt./L microalgal feed concentration was used for this investigation. The highest concentration of microalgal suspension available for testing on the prototype belt filtration system was 6 g dry wt./L obtained from biomass settling tanks at the Lawrence, Kansas domestic wastewater treatment plant. For preparation of feed suspension with concentrations below 10 g dry wt./L, microalgal cultivation was followed by flocculation. A mixed laboratory culture of freshwater species dominated by three eukaryotic green microalgae (Chlorella vulgaris, Scenedesmus sp., and Kirchneriella sp. was cultivated in wastewater effluent. This was followed by flocculation which resulted in a microalgal feed suspension concentration of 4 g dry wt./L. Belt dewatering tests were conducted on microalgal suspensions with feed concentrations of 4 g dry wt./L and 6 g dry wt./L. The maximum microalgal recovery with the belt dewatering system was 46% from the 4 g dry wt./L, and 84% from the 6 g dry wt./L suspensions respectively. The results of this study indicate that microalgal suspension concentrations as low as 6 g dry wt./L can be recovered with a belt filter system improving the overall dewatering efficiency of the system.

Tectonic controlled submarine slidings and dewatering structures

Science.gov (United States)

Yamamoto, Y.; Hirono, T.; Takahashi, M.

2003-04-01

Geologic structures associated with mass movements processes such as slumping, sliding, and creeping can be the key to understanding the tectonic or geologic constraints in the time they were formed. Because they are sensitively reflected by the paleo-topography which must be associated with active tectonics. It must be very useful if the direction of paleo-slope instability is known easily in a wide area. We paid attentions to convolute lamination and flame structure which might be associated with dewatering and loading, respectively. Some recent researches report the possibility that well regulated flame structures might be formed in relation to paleo-slope instability. However, there is an alternative idea that they were reflection of heterogeneous loading associated with ripple marks on the sandy layers. This controversy has not been settled. Accordingly, to evaluate the reliability of the relationship between formation of such structures with well regulated arrays and paleo-slope instability, the Pliocene Chikura Group in the southern part of the Boso Peninsula, central Japan, was studied. The Chikura Group overlying the Miura Group, Miocene accretionary prism, is composed of trench-fill sediments in the lowermost and of trench-slope basin sediments in the upper. The Chikura Group was deposited on an east-west extended sedimentary basin during east-west trending folds and faults development. These indicate the direction of paleo-slope in the Chikura Group due north or south. Flame structures and convolute laminations were recognized over 60 sites in the Chikura Group. They have well-regulated planar arrays which extend almost east west, perpendicular to the direction of paleo-slope instability. Some examples of such structures and slump deposit were observed in the same outcrop. Vergence of these slump deposits were toward north or south, and ridges of flame structures and convolute laminations extend east-west. Experimental study of direct imaging of

Field Evaluation/Demonstration of a Multisegmented Dewatering System for Accreting Beach Sand in a High-Wave-Energy Environment

National Research Council Canada - National Science Library

Curtis, William

1998-01-01

This study documents the use of beach dewatering systems to accrete beach sand and minimize erosion, and to develop quantitative guidance for constructing and operating beach dewatering installations...

Experimental assessment of factors influencing dewatering properties of thermophilically digested biosolids

Energy Technology Data Exchange (ETDEWEB)

Zhou, Jianpeng; Mavinic, Donald S.; Kelly, Harlan G.; Ramey, William D.

2003-07-01

Beneficial land application of processed wastewater sludges (biosolids) is a cost-effective, and environmentally sustainable option for the final disposal of sludges, because nutrients and organic matters in the sludge are recovered and reused as a resource. Thermophilic sludge digestion produces Class A biosolids, which can be reused without restrictions. Recent experience from full-scale thermophilic sludge digestion facilities in North America revealed that, dewatering thermophilically digested biosolids required more polymers to condition than mesophilically digested biosolids. This paper reports a laboratory study that investigated factors having significant impacts on dewatering properties of digested biosolids, and assessed the relationship among digestion, dewatering properties, and characteristics of thermophilically digested biosolids. The experimental work used batch-operated, bench-scale aerobic sludge digesters. Dewaterability was measured as Capillary Suction Time (CST). The study found that feed sludge composition significantly affected dewaterability of digested sludge. Higher percentage of the secondary sludge in the feed sludge corresponded to more significant deterioration in dewaterability. The effect of thermophilic digestion temperatures on dewaterabilty was rapid, occurred within 3-hour of digestion, indicting a heat shock effect, rather than a microbiological effect. When a high shear was applied to the sludge in digesters, it resulted In a significant deterioration in dewaterability in the digested sludge. It appears there was a strong correlation between dewaterability and extracellular biopolymers. Enzymes (protease) treatment confirmed that role of extracellular proteins in affecting the dewatering properties of thermophilic biosolids, also revealed the complex nature of biopolymers' effect on dewaterability. Such effects might be due to protein-polysaccharides interactions, hydrogen bonding, or hydrophilic and hydrophobic

Letramentos acadêmicos e multimodalidade em contexto de EaD semipresencial

OpenAIRE

Komesu, Fabiana

2012-01-01

De uma perspectiva teórica enunciativo-discursiva, este artigo tem como objetivo discutir o processo de constituição do texto em contexto digital, de maneira particularizada, por meio da problematização de modos e recursos semióticos atualizados na produção acadêmica do universitário que utiliza computador com acesso à internet no processo de Educação a Distância (EaD) semipresencial. Interessa investigar como o modelo de letramentos acadêmicos pode ser articulado ao estudo da multimodalidade...

Dewatering cuts drilling mud and disposal costs

International Nuclear Information System (INIS)

West, G.; Pharis, B.

1991-01-01

This paper reports on rig site dewatering of drilling fluids with recycling of processed water that can help an operator to comply with environmental rules by reducing volumes of waste and reducing long term liabilities. It can also reduce disposal costs and provide a cleaner drill site overall. Rig site dewatering is the process of injecting coagulants or flocculating chemicals into the mud entering a large clarifying centrifuge. This coagulates the fine, drilled particles allowing them to be separated from the fluid which can then be handled separately. Most of the environmental concerns during the 1980s involved hazardous materials and toxic wastes. Drilling fluids, many of which are chemically benign, have escaped many of the difficult-to-comply-with rules and regulations. During the 1990s, however, operators may be required to submit a written plan for liquid waste reduction for even nonhazardous materials. Many states and local agencies may institute total bans on oil field wastes. Drilling rigs typically produce about 1 bbl of liquid waste for every 1 ft of hole drilled. Thus, a typical drilling operation can produce a large quantity of waste

Waste water from dewatering of peat

International Nuclear Information System (INIS)

Ringqvist, L.; Bergner, K.; Olsson, Tommy; Bystroem, P.

1991-01-01

The influence of waste water from mechanical dewatering of peat was tested on two species of stream invertebrates. We compared the effects of waste water from peat without any chemical treatment, and waste water from peat where one of the following treatments of the peat had preceded dewatering; a: acidification combined with addition of the cationic polymer Zetag 78 FS40, b: addition of aluminium in combination with the anionic polymer Magnafloc E10, c: polymerisation of the peat by acidification and addition of ferrous chloride and hydrogen peroxide. Waste water from Al/Magnafloc and from the polymerisation treatments had a higher content of suspended matter and a higher oxygen demand than those of other treatments. Total metal content of the water from all treatments was higher than in water from non-treated peat. Survival and growth of nymphs of the mayfly Heptagenia fuscogrisa and the stonefly Nemoura cinerea were compared in waste water from the different treatments. In all tests, the waste water was diluted to 5% (volume) with unchlorinated tapwater and pH was between 7.0-8.0 in all treatments during the experiment. The nymphs were fed with birch leaves that had been incubated in natural stream water for one month. Under these conditions, we did not find any significant effect of waste water on either survival or growth of these two species

Synergetic pretreatment of waste activated sludge by hydrodynamic cavitation combined with Fenton reaction for enhanced dewatering.

Science.gov (United States)

Cai, Meiqiang; Hu, Jianqiang; Lian, Guanghu; Xiao, Ruiyang; Song, Zhijun; Jin, Micong; Dong, Chunying; Wang, Quanyuan; Luo, Dewen; Wei, Zongsu

2018-04-01

The dewatering of waste activated sludge by integrated hydrodynamic cavitation (HC) and Fenton reaction was explored in this study. We first investigated the effects of initial pH, sludge concentration, flow rate, and H 2 O 2 concentration on the sludge dewaterability represented by water content, capillary suction time and specific resistance to filtration. The results of dewatering tests showed that acidic pH and low sludge concentration were favorable to improve dewatering performance in the HC/Fenton system, whereas optimal flow rate and H 2 O 2 concentration applied depended on the system operation. To reveal the synergism of HC/Fenton treatment, a suite of analysis were implemented: three-dimensional excitation emission matrix (3-DEEM) spectra of extracellular polymeric substances (EPS) such as proteins and polysaccharides, zeta potential and particle size of sludge flocs, and SEM/TEM imaging of sludge morphology. The characterization results indicate a three-step mechanism, namely HC fracture of different EPS in sludge flocs, Fenton oxidation of the released EPS, and Fe(III) re-flocculation, that is responsible for the synergistically enhanced sludge dewatering. Results of current study provide a basis to improve our understanding on the sludge dewatering performance by HC/Fenton treatment and possible scale-up of the technology for use in wastewater treatment plants. Copyright © 2017 Elsevier B.V. All rights reserved.

Electroacoustic theory for concentrated colloids with overlapped DLs at arbitrary kappa alpha. I. Application to nanocolloids and nonaqueous colloids.

Science.gov (United States)

Shilov, V N; Borkovskaja, Y B; Dukhin, A S

2004-09-15

Existing theories of electroacoustic phenomena in concentrated colloids neglect the possibility of double layer overlap and are valid mostly for the "thin double layer," when the double layer thickness is much less than the particle size. In this paper we present a new electroacoustic theory which removes this restriction. This would make this new theory applicable to characterizing a variety of aqueous nanocolloids and of nonaqueous dispersions. There are two versions of the theory leading to the analytical solutions. The first version corresponds to strongly overlapped diffuse layers (so-called quasi-homogeneous model). It yields a simple analytical formula for colloid vibration current (CVI), which is valid for arbitrary ultrasound frequency, but for restricted kappa alpha range. This version of the theory, as well the Smoluchowski theory for microelectrophoresis, is independent of particle shape and polydispersity. This makes it very attractive for practical use, with the hope that it might be as useful as classical Smoluchowski theory. In order to determine the kappa alpha range of the quasi-homogeneous model validity we develop the second version that limits ultrasound frequency, but applies no restriction on kappa alpha. The ultrasound frequency should substantially exceed the Maxwell-Wagner relaxation frequency. This limitation makes active conductivity related current negligible compared to the passive dielectric displacement current. It is possible to derive an expression for CVI in the concentrated dispersion as formulae inhering definite integrals with integrands depending on equilibrium potential distribution. This second version allowed us to estimate the ranges of the applicability of the first, quasi-homogeneous version. It turns out that the quasi-homogeneous model works for kappa alpha values up to almost 1. For instance, at volume fraction 30%, the highest kappa alpha limit of the quasi-homogeneous model is 0.65. Therefore, this version of the

Capacidades do Estado brasileiro e arquitetura institucional da EaD: da organização burocrática à autonomia inserida dos órgãos estatais

Directory of Open Access Journals (Sweden)

Daniela da Costa Britto Pereira Lima

2018-04-01

Full Text Available Resumo: O tema deste estudo é a arquitetura institucional da educação a distância (EaD no Brasil sob a ótica das capacidades do Estado no que se refere à organização burocrática. Seu objetivo geral é apresentar e discutir algumas das capacidades do Estado brasileiro para gerir sua política pública de EaD. A pesquisa é do tipo bibliográfica e de natureza empírica, com suporte teórico em Evans (1993, 1995, 2004. O estudo empírico considerou o mapeamento e a análise da arquitetura institucional da EaD no Brasil entre 2010 e 2013 (LIMA, 2013. Constata-se que o Estado precisa rever sua arquitetura institucional da EaD, visando desenvolver a sua capacidade de organização burocrática e autonomia inserida, para passar de um Estado intermediário para desenvolvimentista. Palavras-chave: Educação a distância; educação superior; capacidades do Estado; arquitetura institucional.   Abstract: The theme of this study is the institutional architecture of distance education - EaD - in Brazil, from the point of view of the state's capabilities, regarding the bureaucratic organization. Its general objective is to present and discuss some of the capabilities of the Brazilian State to manage it's public DE policy. The research is a bibliographical and empirical study, with theoretical support in Evans (1993, 1995, 2004. The empirical study considered the mapping and analysis of the institutional architecture of EaD in Brazil between 2010 and 2013 (LIMA, 2013. It concludes that the Brazilian State needs to reassess its DE institutional architecture as a means to develop its bureaucratic organization capacity and inserted autonomy, and as a condition to move from an intermediary State to a developed one. Keywords: distance education; higher education; State capacity; institutional architecture.   Resumen: El tema de este estudio es la arquitectura institucional de la educación a distancia (EaD en Brasil bajo la óptica de las capacidades

Ecotoxicological assessment of dewatered drinking water treatment residue for environmental recycling.

Science.gov (United States)

Yuan, Nannan; Wang, Changhui; Wendling, Laura A; Pei, Yuansheng

2017-09-01

The beneficial recycle of drinking water treatment residue (DWTR) in environmental remediation has been demonstrated in many reports. However, the lack of information concerning the potential toxicity of dewatered DWTR hinders its widespread use. The present study examined the ecotoxicity of dewatered aluminum (Al) and iron (Fe) DWTR leachates to a green alga, Chlorella vulgaris. Data from the variations of cell density and chlorophyll a content suggested that algal growth in DWTR leachates was inhibited. The algal cellular oxidation stress was initially induced but completely eliminated within 72 h by antioxidant enzymes. The expression of three photosynthesis-related algae genes (psaB, psbC, and rbcL) also temporarily decreased (within 72 h). Moreover, the algal cells showed intact cytomembranes after exposure to DWTR leachates. Further investigation confirmed that inhibition of algal growth was due to DWTR-induced phosphorus (P) deficiency in growth medium, rather than potentially toxic contaminants (e.g. copper and Al) contained in DWTR. Interestingly, the leachates could potentially promote algal growth via increasing the supply of new components (e.g. calcium, kalium, magnesium, and ammonia nitrogen) from DWTR. In summary, based on the algae toxicity test, the dewatered Fe/Al DWTR was nontoxic and its environment recycling does not represent an ecotoxicological risk to algae.

Pervaporation applied for dewatering of reaction mixture during esterification

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Krasiński Andrzej

2016-03-01

Full Text Available In this work the esterification of diethyl tartrate was studied. The research was focused on the enhancement of reversible reaction yield, which is accomplished by dewatering of the reaction mixture. The removal of water shifts the equilibrium towards the main product. Pervaporation was applied for this purpose, and results were compared to distillation. The advantages and limitations of both processes are discussed. The experimental part consists of dewatering of mixture after the reaction had reached the equilibrium, and was subsequently fed to the test rig equipped with a single zeolite membrane purchased from Pervatech B.V. Results show a significant conversion increase as a result of water removal by pervaporation. Compared to distillation no addition of organics is necessary to efficiently remove water above the azeotrope. Nevertheless, some limitations and issues which call for optimisation are pointed out. A simple numerical model is proposed to support design and sizing of the pervaporation system. Various modes of integrated system operation are also briefly discussed.

Centrifugal dewatering of acid casein curd: effect of casein manufacturing and centrifugation variables on curd compression in a laboratory centrifuge.

Science.gov (United States)

Munro, P A; Van Til, H J

1988-10-20

Data relevant to curd compression in a horizontal, solid bowl decanter centrifuge have been obtained by studying the dewatering of acid casein curd in a batch laboratory centrifuge. Analysis of curd compression under centrifugal force predicts a moisture content gradient in the dewatered curd from a maximum at the curd-liquid interface to a minimum at the centrifuge bowl wall. This moisture content gradient was also measured experimentally, and its practical implications are discussed. Increases in centrifugal force, centrifugation time, and centrifugation temperature all caused a marked de crease in dewatered curd moisture content, whereas in creases in precipitation pH and maximum washing temperature caused a smaller decrease in dewatered curd moisture content.

Dewatering of ultrafine coal: Final report, August 1984-December 1986

Energy Technology Data Exchange (ETDEWEB)

Chiang, Shiao-Hung; Klinzing, G.E.; Morsi, B.I.; Tierney, J.W.; Badgujar, M.; Binkley, T.; Cheng, Yisun; Huang, Suxuan; Qamar, I.; Venkatadri, R.

1986-12-01

The surfactant, Aerosol-OT, was used to wash distilled water cakes. In previous studies, cakes were washed with Triton X-114. The dewatering performance and influence on cake structure of the two reagents are compared. Also, filter cakes were analyzed using an image analysis system and micrographic analysis of coal particles was initiated. In the area of theoretical modelling, the concept of bond-flow correlation greatly improved the network model predicting the experimental desaturation curves. Predicted results for treated cakes suggested that the effect of the presence of surface-active agents was adequately accounted for. The effects of the various operating conditions on the filtration/dewatering characteristics of the 10 ..mu..m coal particles were assessed and comparisons with the -32 mesh coal were made as to its trends in response to changes in the operating conditions. 20 refs., 75 figs., 17 tabs.

Dewatering tailings impoundments : interior drains

International Nuclear Information System (INIS)

Charlie, W.A.; Doehring, D.O.; Durnford, D.S.

1984-01-01

For the design of a new uranium tailings impoundment in the western United States, it was proposed that an interior drainage system be considered to economically and reliably minimize potential short- and long-term environmental impacts. The objectives were to decrease the effective hydraulic head on the clay liner, to dewater and stabilize the tailings, and to increase the amount of water recycled to the mill. In addition, desaturation of the impoundment would induce capillary pressure (negative porewater pressure), further reducing the potential movement of dissolved pollutants. This paper presents saturated and unsaturated seepage principles and reviews the concept, criteria and design of the various interior drainage systems considered

Locally produced natural conditioners for dewatering of faecal sludge.

Science.gov (United States)

Gold, Moritz; Dayer, Pauline; Faye, Marie Christine Amie Sene; Clair, Guillaume; Seck, Alsane; Niang, Seydou; Morgenroth, Eberhard; Strande, Linda

2016-11-01

In urban areas of low-income countries, treatment of faecal sludge (FS) is insufficient or non-existent. This results in large amounts of FS being dumped into the environment. Existing treatment technologies for FS, such as settling-thickening tanks and drying beds, are land intensive which is limiting in urban areas. Enhanced settling and dewatering by conditioning was evaluated in order to reduce the treatment footprint (or increase treatment capacity). Conventional wastewater conditioners, such as commercially available lime and polymers, are expensive, and commonly rely on complex supply chains for use in low-income countries. Therefore, the treatment performance of five conditioners which could be produced locally was evaluated: Moringa oleifera seeds and press cake, Jatropha curcas seeds, Jatropha Calotropis leaves and chitosan. M. oleifera seeds and press cake, and chitosan improved settling and dewatering and had a similar performance compared to lime and polymers. Optimal dosages were 400-500 kg M. oleifera/t TS, 300-800 kg lime/t TS and 25-50 kg polymer solution/t TS. In comparison, chitosan required 1.5-3.75 kg/t TS. These dosages are comparable to those recommended for wastewater (sludge). The results indicate that conditioning of FS can reduce total suspended solids (TSS) in the effluent of settling-thickening tanks by 22-81% and reduce dewatering time with drying beds by 59-97%. This means that the area of drying beds could be reduced by 59-97% with end-use as soil conditioner, or 9-26% as solid fuel. Least expensive options and availability will depend on the local context. In Dakar, Senegal, chitosan produced from shrimp waste appears to be most promising.

Effects of different sludge disintegration methods on sludge moisture distribution and dewatering performance.

Science.gov (United States)

Jin, Lingyun; Zhang, Guangming; Zheng, Xiang

2015-02-01

A key step in sludge treatment is sludge dewatering. However, activated sludge is generally very difficult to be dewatered. Sludge dewatering performance is largely affected by the sludge moisture distribution. Sludge disintegration can destroy the sludge structure and cell wall, so as change the sludge floc structure and moisture distribution, thus affecting the dewatering performance of sludge. In this article, the disintegration methods were ultrasound treatment, K2FeO4 oxidation and KMnO4 oxidation. The degree of disintegration (DDCOD), sludge moisture distribution and the final water content of sludge cake after centrifuging were measured. Results showed that three disintegration methods were all effective, and K2FeO4 oxidation was more efficient than KMnO4 oxidation. The content of free water increased obviously with K2FeO4 and KMnO4 oxidations, while it decreased with ultrasound treatment. The changes of free water and interstitial water were in the opposite trend. The content of bounding water decreased with K2FeO4 oxidation, and increased slightly with KMnO4 oxidation, while it increased obviously with ultrasound treatment. The water content of sludge cake after centrifuging decreased with K2FeO4 oxidation, and did not changed with KMnO4 oxidation, but increased obviously with ultrasound treatment. In summary, ultrasound treatment deteriorated the sludge dewaterability, while K2FeO4 and KMnO4 oxidation improved the sludge dewaterability. Copyright © 2014. Published by Elsevier B.V.

[Magnetic Fe₃O₄Microparticles Conditioning-Pressure Electro-osmotic Dewatering (MPEOD) of Sewage Sludge].

Science.gov (United States)

Qian, Xu; Wang, Yi-li; Zhao, Li

2016-05-15

For magnetic Fe₃O₄ microparticles conditioning--pressure electro-osmotic dewatering (MPEOD) process of activated sludge (AS), the effects of operating parameters (optimal dosage of Fe₃O₄, electric field duration, mechanical pressure and voltage) on the dewatering efficiency and energy consumption were investigated, and the optimal conditions were determined. Moreover, the properties of supernatant and sludge along MPEOD process were studied as well as the interaction force between the sludge biosolids. Taking the energy consumption into consideration, the results showed that the optimal dewatering effect for AS could be achieved with a magnetic Fe₃O₄ microparticles dosage of 0.15 g · g⁻¹, an electric field duration of 2 h, a mechanical pressure of 400-600 kPa and a voltage of 30-50 V. When MPEOD was conducted at 400 kPa and 50 V for 2 h, the sludge reduction rate reached 98.30%, the percentage of water removal was 99.34% and the moisture content of AS decreased from 99.18% to 44.46%. The corresponding consumption of energy was 0.013 3 kW · h · kg⁻¹. The coagulation mechanism played a slight role in the AS conditioning with magnetic Fe₃O₄ micro-particles. In fact, magnetic Fe₃O₄micro-particles could greatly decrease the acid-base interaction (WA) between AS biosolids, cause floc growth and enlarge pores in AS aggregates, which will be beneficial to AS dewatering. Compared to DLVO theory, the extended DLVO theory could accurately describe the aggregation and dispersion behavior of sludge particles.

Full-scale performance of selected starch-based biodegradable polymers in sludge dewatering and recommendation for applications.

Science.gov (United States)

Zhou, Kuangxin; Stüber, Johan; Schubert, Rabea-Luisa; Kabbe, Christian; Barjenbruch, Matthias

2018-01-01

Agricultural reuse of dewatered sludge is a valid route for sludge valorization for small and mid-size wastewater treatment plants (WWTPs) due to the direct utilization of nutrients. A more stringent of German fertilizer ordinance requires the degradation of 20% of the synthetic additives like polymeric substance within two years, which came into force on 1 January 2017. This study assessed the use of starch-based polymers for full-scale dewatering of municipal sewage sludge. The laboratory-scale and pilot-scale trials paved the way for full-scale trials at three WWTPs in Germany. The general feasibility of applying starch-based 'green' polymers in full-scale centrifugation was demonstrated. Depending on the sludge type and the process used, the substitution potential was up to 70%. Substitution of 20-30% of the polyacrylamide (PAM)-based polymer was shown to achieve similar total solids (TS) of the dewatered sludge. Optimization of operational parameters as well as machinery set up in WWTPs is recommended in order to improve the shear stability force of sludge flocs and to achieve higher substitution potential. This study suggests that starch-based biodegradable polymers have great potential as alternatives to synthetic polymers in sludge dewatering.

Electroosmotic dewatering of chalk sludge, iron hydroxide sludge, wet fly ash and biomass sludge

DEFF Research Database (Denmark)

Hansen, H.K.; Christensen, Iben Vernegren; Ottosen, Lisbeth M.

2003-01-01

. Casagrande's coefficients were determined for the four materials at different water contents. The experiments in this work showed that chalk could be dewatered from 40% to 79% DM (dry matter), fly ash from 75 to 82% DM, iron hydroxide sludge from 2.7 to 19% DM and biomass from 3 to 33% DM by electroosmosis....... The process was not optimised indicating that higher dry matter contents could be achieved by electroosmosis. It was possible to relate Casagrande's coefficient directly to the electroosmotic coefficient obtained by dewatering experiments....

Model test on partial expansion in stratified subsidence during foundation pit dewatering

Science.gov (United States)

Wang, Jianxiu; Deng, Yansheng; Ma, Ruiqiang; Liu, Xiaotian; Guo, Qingfeng; Liu, Shaoli; Shao, Yule; Wu, Linbo; Zhou, Jie; Yang, Tianliang; Wang, Hanmei; Huang, Xinlei

2018-02-01

Partial expansion was observed in stratified subsidence during foundation pit dewatering. However, the phenomenon was suspected to be an error because the compression of layers is known to occur when subsidence occurs. A slice of the subsidence cone induced by drawdown was selected as the prototype. Model tests were performed to investigate the phenomenon. The underlying confined aquifer was generated as a movable rigid plate with a hinge at one end. The overlying layers were simulated with remolded materials collected from a construction site. Model tests performed under the conceptual model indicated that partial expansion occurred in stratified settlements under coordination deformation and consolidation conditions. During foundation pit dewatering, rapid drawdown resulted in rapid subsidence in the dewatered confined aquifer. The rapidly subsiding confined aquifer top was the bottom deformation boundary of the overlying layers. Non-coordination deformation was observed at the top and bottom of the subsiding overlying layers. The subsidence of overlying layers was larger at the bottom than at the top. The layers expanded and became thicker. The phenomenon was verified using numerical simulation method based on finite difference method. Compared with numerical simulation results, the boundary effect of the physical tests was obvious in the observation point close to the movable endpoint. The tensile stress of the overlying soil layers induced by the underlying settlement of dewatered confined aquifer contributed to the expansion phenomenon. The partial expansion of overlying soil layers was defined as inversed rebound. The inversed rebound was induced by inversed coordination deformation. Compression was induced by the consolidation in the overlying soil layers because of drainage. Partial expansion occurred when the expansion exceeded the compression. Considering the inversed rebound, traditional layer-wise summation method for calculating subsidence should be

Fundamental study for improvement of dewatering of fine coal/refuse. Final report, August 1981-December 1984

Energy Technology Data Exchange (ETDEWEB)

Chiang, S.H.; Klinzing, G.E.; Morsi, B.I.; Tierney, J.W.; Binkley, T.; Chi, S.M.; Huang, S.; Qamar, I.; Venkatadri, R.

1984-12-01

Fine coal in slurry form must be dewatered to minimize handling and transportation problems and be reduced to a desirable level for subsequent preparation of coal/water mixtures as a substitute utility fuel. The current practice is inadequate for the dewatering of fine coal, particularly for coal particles with sizes smaller than 400 mesh. Therefore, it is most desirable to develop improved mechanical methods for reducing the moisture content of fine coal. In the light of this, a fundamental study of the dewatering of fine coal/refuse was initiated in June 1979 and continued through 1984. The overall objective of the study is to seek improved methods of dewatering through a better understanding of the filtration and post-filtration processes. As a first step, efforts have been focused on the mechanism of dewatering in terms of the basic properties of coal (and refuse) particles and the microstructures of filter cakes, and their relations to filtration rate and final moisture content. Pittsburgh seam-Bruceton Mine coal was used as a base coal. During the past year, filter cakes from coals with widely varying size ranges were micrographically characterized. The effects of a number of surface active agents and of entrapped air bubbles on the filter cake properties were also studied. Modules of the network model for calculating single phase and two phase permeabilities were formulated and tested. The report is divided into four parts: summary and deliverables; work forecast for 1984-1985; detailed description of technical progress; and appendices. 21 refs., 55 figs., 17 tabs.

On-line Monitoring System Based on Principle of Electro-acoustic Monitoring for Transformer Partial Discharge

Directory of Open Access Journals (Sweden)

Guang Ya LIU

2014-02-01

Full Text Available Partial discharge inside a transformer is mainly responsible for the insulation aging and damage of the transformer. However, partial discharge is usually accompanied by external signals like sound, light and electrical signals and detectable physical phenomena such as characteristical gas and dielectric loss. Therefore, it is of great significance to monitor online the external signals and phenomena formed during partial discharge of the transformer when the transformer diagnoses faults. This paper gives a comprehensive overview of the electro-acoustic joint monitoring principles and its monitoring systems and the judgment skills concerned, on the basis of which the monitoring system is designed.

New design of the pulsed electro-acoustic upper electrode for space charge measurements during electronic irradiation

Energy Technology Data Exchange (ETDEWEB)

Riffaud, J.; Griseri, V.; Berquez, L. [UPS, LAPLACE, Université de Toulouse, 118 Route de Narbonne, Toulouse F-31062, France and CNRS, LAPLACE, Toulouse F-31062 (France)

2016-07-15

The behaviour of space charges injected in irradiated dielectrics has been studied for many years for space industry applications. In our case, the pulsed electro-acoustic method is chosen in order to determine the spatial distribution of injected electrons. The feasibility of a ring-shaped electrode which will allow the measurements during irradiation is presented. In this paper, a computer simulation is made in order to determine the parameters to design the electrode and find its position above the sample. The obtained experimental results on polyethylene naphthalate samples realized during electronic irradiation and through relaxation under vacuum will be presented and discussed.

Cleaning and dewatering fine coal

Science.gov (United States)

Yoon, Roe-Hoan; Eraydin, Mert K.; Freeland, Chad

2017-10-17

Fine coal is cleaned of its mineral matter impurities and dewatered by mixing the aqueous slurry containing both with a hydrophobic liquid, subjecting the mixture to a phase separation. The resulting hydrophobic liquid phase contains coal particles free of surface moisture and droplets of water stabilized by coal particles, while the aqueous phase contains the mineral matter. By separating the entrained water droplets from the coal particles mechanically, a clean coal product of substantially reduced mineral matter and moisture contents is obtained. The spent hydrophobic liquid is separated from the clean coal product and recycled. The process can also be used to separate one type of hydrophilic particles from another by selectively hydrophobizing one.

Análise da utilização das tecnologias da informação e comunicação na educação a distância (EaD.

Directory of Open Access Journals (Sweden)

Carla Simone Pires

2017-02-01

Full Text Available A EaD se caracteriza por docentes e discentes fisicamente separados, conectados por TICs. No Brasil a EaD não é recente, entretanto, tem aumentado nos últimos anos devido a políticas públicas e à evolução das TICs, entretanto, a sua aplicação normalmente tem foco na economia de recursos. Apesar das dificuldades encontradas, é tendência mundial e converge para o uso de tecnologias. Neste sentido, TICs podem causar inclusão/exclusão social, dependendo de como sua utilização é planejadas. O mesmo ocorre com processos avaliativos, que mostram fragilidades. Os resultados permitem concluir que a transição para EaD não apresenta mudanças de práticas pedagógicas. Apesar disto, tem importante papel social, uma vez que vem suprir demandas reprimidas no que tange o acesso à educação superior, além de incentivar o desenvolvimento de municípios com Baixos Índice de Desenvolvimento Humano (IDH e Índice de Desenvolvimento da Educação Básica (IDEB. Ainda, mostra a necessidade de redimensionar as práticas de ensino (reinventando usos para TICs na transição entre ensino presencial e EaD, possibilitando que a EaD assuma sua função social na educação brasileira. Neste sentido,  Este trabalho teve como objetivo fazer um estudo analítico do contexto da Educação a Distância (EaD no Brasil, as práticas pedagógicas usadas e o papel das Tecnologias de Informação (TICs neste processo.

Acceleration of organic removal and electricity generation from dewatered oily sludge in a bioelectrochemical system by rhamnolipid addition.

Science.gov (United States)

Zhang, Yunshu; Zhao, Qingliang; Jiang, Junqiu; Wang, Kun; Wei, Liangliang; Ding, Jing; Yu, Hang

2017-11-01

Conversion of biomass energy of dewatered oily sludge to electricity is the rate-limiting process in bioelectrochemical system (BES). In this study, 2mgg -1 rhamnolipids were added to dewatered oily sludge, resulting in a significant enhancement in maximum power density from 3.84±0.37 to 8.63±0.81Wm -3 , together with an increase in total organic carbon (TOC) and total petroleum hydrocarbon (TPH) removal from 24.52±4.30 to 36.15±2.79mgg -1 and 29.51±3.30 to 39.80±2.47mgg -1 , respectively. Rhamnolipids can also enhance the solubilization and promote the hydrolysis of dewatered oily sludge with increases in SOCD from 14.93±2.44 to 18.40±0.08mgg -1 and VFAs from 1.02±0.07 to 1.39±0.12mgg -1 . Furthermore, bacteria related to substrate degradation were predominant in dewatered oily sludge, and bacteria related to the sulfate/sulfide cycle were significantly enriched by rhamnolipid addition. Copyright © 2017 Elsevier Ltd. All rights reserved.

Efficient Calculation of Dewatered and Entrapped Areas Using Hydrodynamic Modeling and GIS

International Nuclear Information System (INIS)

Richmond, Marshall C.; Perkins, William A.

2009-01-01

River waters downstream of a hydroelectric project are often subject to rapidly changing discharge. Abrupt decreases in discharge can quickly dewater and expose some areas and isolate other areas from the main river channel, potentially stranding or entrapping fish, which often results in mortality. A methodology is described to estimate the areas dewatered or entrapped by a specific reduction in upstream discharge. A one-dimensional hydrodynamic model was used to simulate steady flows. Using flow simulation results from the model and a geographic information system (GIS), estimates of dewatered and entrapped areas were made for a wide discharge range. The methodology was applied to the Hanford Reach of the Columbia River in central Washington State. Results showed that a 280 m 3 /s discharge reduction affected the most area at discharges less than 3400 m 3 /s. At flows above 3400 m 3 /s, the affected area by a 280 m 3 /s discharge reduction (about 25 ha) was relatively constant. A 280 m 3 /s discharge reduction at lower flows affected about twice as much area. The methodology and resulting area estimates were, at the time of writing, being used to identify discharge regimes, and associated water surface elevations, that might be expected to minimize adverse impacts on juvenile fall chinook salmon (Oncorhynchus tshawytscha) that rear in the shallow near-shore areas in the Hanford Reach

Monitoring and troubleshooting of non-filamentous settling and dewatering problems in an industrial activated sludge treatment plant

DEFF Research Database (Denmark)

Kjellerup, B. V.; Keiding, Kristian; Nielsen, Per Halkjær

2001-01-01

dewaterability. The monitoring program revealed that a deterioration of the floc strength and the settling properties in the process tanks was closely connected to downstream dewatering problems and poor effluent quality. Particularly severe problems were observed a few weeks after the production at the factory......A large industrial activated sludge wastewater treatment plant had temporary problems with settling and dewatering of the sludge. Microscopical investigations revealed that the poor settling properties were not due to presence of filamentous bacteria, but poor floc properties. In order...... to characterise the changes in floc properties that led to settling and dewatering problems and to find reasons for this taking place, a comprehensive monitoring program was conducted during more than one year. The monitoring program included various measurements of floc settleability, floc strength and sludge...

A Case Study on Stratified Settlement and Rebound Characteristics due to Dewatering in Shanghai Subway Station

OpenAIRE

Wang, Jianxiu; Huang, Tianrong; Sui, Dongchang

2013-01-01

Based on the Yishan Metro Station Project of Shanghai Metro Line number 9, a centrifugal model test was conducted to investigate the behavior of stratified settlement and rebound (SSR) of Shanghai soft clay caused by dewatering in deep subway station pit. The soil model was composed of three layers, and the dewatering process was simulated by self-invention of decompressing devise. The results indicate that SSR occurs when the decompression was carried out, and only negative rebound was found...

Electroosmotic dewatering of chalk sludge, iron hydroxide sludge, wet fly ash and biomass

Energy Technology Data Exchange (ETDEWEB)

Hansen, H.K.; Kristensen, I.V.; Ottosen, L.M.; Villumsen, A. [Dept. of Geology and Geotechnical Engineering, The Technical Univ. of Denmark, Lyngby (Denmark)

2001-07-01

Electroosmotic dewatering has been tested in laboratory cells for 4 different porous materials: chalk sludge, iron hydroxide sludge, wet fly ash and biomass sludge from enzyme production. In all cases it was possible to remove water when passing electric DC current through the material. Casagrande's coefficients for the three materials where determined at different water contents. In the electroosmotic experiments shown in this work chalk can be dewatered from 40% to 79% DM (dry matter), fly ash from 75 to 82% DM, iron hydroxide sludge from 2.7 to 19% DM and biomass from 3 to 33% DM. The process was not optimised indicating that higher dry matter contents could be achieved. (orig.)

Web 2.0 e EAD: riscos e possibilidades

Directory of Open Access Journals (Sweden)

Richard Romancini

2010-06-01

Full Text Available O artigo evidencia o crescimento das possibilidades de uso de tecnologias digitais associadas à chamada “web 2.0”, entre os usuários da internet. Discute a relação desse contexto com a educação mediada por tecnologias, em particular a Educação a Distância (EAD, notando que existe o paradoxal risco de que a utilização desses novos recursos reforce paradigmas educativos informacionais/reprodutivistas. Entretanto, argumenta-se que o uso reflexivo das possibilidades que surgiram no mundo digital pode favorecer a construção de espaços de diálogos na educação on-line, dando um sentido mais comunicativo/construtivista a processos de educação virtual. Por fim, nota-se que, para este cenário mais positivo, é necessário, também, que haja o desenvolvimento de competências por parte dos participantes (professores e estudantes das ações educativas no âmbito digital.

Monitoring and optimizing the co-composting of dewatered sludge: a mixture experimental design approach.

Science.gov (United States)

Komilis, Dimitrios; Evangelou, Alexandros; Voudrias, Evangelos

2011-09-01

The management of dewatered wastewater sludge is a major issue worldwide. Sludge disposal to landfills is not sustainable and thus alternative treatment techniques are being sought. The objective of this work was to determine optimal mixing ratios of dewatered sludge with other organic amendments in order to maximize the degradability of the mixtures during composting. This objective was achieved using mixture experimental design principles. An additional objective was to study the impact of the initial C/N ratio and moisture contents on the co-composting process of dewatered sludge. The composting process was monitored through measurements of O(2) uptake rates, CO(2) evolution, temperature profile and solids reduction. Eight (8) runs were performed in 100 L insulated air-tight bioreactors under a dynamic air flow regime. The initial mixtures were prepared using dewatered wastewater sludge, mixed paper wastes, food wastes, tree branches and sawdust at various initial C/N ratios and moisture contents. According to empirical modeling, mixtures of sludge and food waste mixtures at 1:1 ratio (ww, wet weight) maximize degradability. Structural amendments should be maintained below 30% to reach thermophilic temperatures. The initial C/N ratio and initial moisture content of the mixture were not found to influence the decomposition process. The bio C/bio N ratio started from around 10, for all runs, decreased during the middle of the process and increased to up to 20 at the end of the process. The solid carbon reduction of the mixtures without the branches ranged from 28% to 62%, whilst solid N reductions ranged from 30% to 63%. Respiratory quotients had a decreasing trend throughout the composting process. Copyright © 2011 Elsevier Ltd. All rights reserved.

Prediction and verification of centrifugal dewatering of P. pastoris fermentation cultures using an ultra scale-down approach.

Science.gov (United States)

Lopes, A G; Keshavarz-Moore, E

2012-08-01

Recent years have seen a dramatic rise in fermentation broth cell densities and a shift to extracellular product expression in microbial cells. As a result, dewatering characteristics during cell separation is of importance, as any liquor trapped in the sediment results in loss of product, and thus a decrease in product recovery. In this study, an ultra scale-down (USD) approach was developed to enable the rapid assessment of dewatering performance of pilot-scale centrifuges with intermittent solids discharge. The results were then verified at scale for two types of pilot-scale centrifuges: a tubular bowl equipment and a disk-stack centrifuge. Initial experiments showed that employing a laboratory-scale centrifugal mimic based on using a comparable feed concentration to that of the pilot-scale centrifuge, does not successfully predict the dewatering performance at scale (P-value centrifuge. Initial experiments used Baker's yeast feed suspensions followed by fresh Pichia pastoris fermentation cultures. This work presents a simple and novel USD approach to predict dewatering levels in two types of pilot-scale centrifuges using small quantities of feedstock (centrifuge needs to be operated, reducing the need for repeated pilot-scale runs during early stages of process development. Copyright © 2012 Wiley Periodicals, Inc.

Bendable Electro-Acoustic Transducer Fabricated Utilizing Frequency Dispersion of Elastic Modulus

Science.gov (United States)

Miyoshi, Tetsu; Ohga, Juro

2013-09-01

To realize the speaker diaphragm that can be united with a flexible display without deteriorating lightweight properties and flexibility, a novel bendable electro-acoustic transducer (BEAT) based on 0-3-type piezoelectric composites has been developed. To overcome the trade-off between flexibility and the transmission efficiency of vibration energy, a viscoelastic polymer that has local maximum points in the loss factor as well as large frequency dispersion in the storage modulus near room temperature was employed as the matrix of the piezoelectric composite layer. Against the comparatively slow (10 Hz or less) deformation from the outside, the viscoelastic matrix is viscous enough to prevent cracking and delamination. On the other hand, in the audible range (20 Hz to 20 kHz), the matrix is elastic enough to transmit piezoelectric vibration energy, maintaining a moderately large loss factor as well as a high sound velocity. For the first time, we successfully demonstrated a rollable speaker that can continue to generate a high-quality sound while being rolled and unrolled repeatedly onto a cylinder with a curvature radius of 4 mm.

Sludge dewatering on filters aiming the utilization as fuel; Desaguamento de lodos em filtro visando aproveitamento como combustivel

Energy Technology Data Exchange (ETDEWEB)

Paschoalim, Luis Gustavo; Neves, Jose Mangolini

1993-12-31

This work presents modern methodologies for sludge dewatering and alternatives for environmental disposal of the so obtained cakes. Among the possible alternatives, special emphasis is given to the characterization and study of the variables which determine the behaviour of dewatering operation of sludges form pulp and paper industries. Results are presents for bench scale tests and pilot plant tests 28 refs., 9 figs., 7 tabs.

Sludge dewatering on filters aiming the utilization as fuel; Desaguamento de lodos em filtro visando aproveitamento como combustivel

Energy Technology Data Exchange (ETDEWEB)

Paschoalim, Luis Gustavo; Neves, Jose Mangolini

1992-12-31

This work presents modern methodologies for sludge dewatering and alternatives for environmental disposal of the so obtained cakes. Among the possible alternatives, special emphasis is given to the characterization and study of the variables which determine the behaviour of dewatering operation of sludges form pulp and paper industries. Results are presents for bench scale tests and pilot plant tests 28 refs., 9 figs., 7 tabs.

Dewatering and low-temperature pyrolysis of oily sludge in the presence of various agricultural biomasses.

Science.gov (United States)

Zhao, Song; Zhou, Xiehong; Wang, Chuanyi; Jia, Hanzhong

2017-08-24

Pyrolysis is potentially an effective treatment of waste oil residues for recovery of petroleum hydrocarbons, and the addition of biomass is expected to improve its dewatering and pyrolysis behavior. In this study, the dewatering and low-temperature co-pyrolysis of oil-containing sludge in the presence of various agricultural biomasses, such as rice husk, walnut shell, sawdust, and apricot shell, were explored. As a result, the water content gradually decreases with the increase of biomass addition within 0-1.0 wt % in original oily sludge. Comparatively, the dewatering efficiency of sludge in the presence of four types of biomasses follows the order of apricot shell > walnut shell > rice husk > sawdust. On the other hand, rice husk and sawdust are relatively more efficient in the recovery of petroleum hydrocarbons compared with walnut shell and apricot shell. The recovery efficiency generally increased with the increase in the biomass content in the range of 0-0.2 wt %, then exhibited a gradually decreasing trend with the increase in the biomass content from 0.2 to 1.0 wt %. The results suggest that optimum amount of biomass plays an important role in the recovery efficiency. In addition, the addition of biomass (such as rice husk) also promotes the formation of C x H y and CO, increasing the calorific value of pyrolysis residue, and controlled the pollution components of the exhaust gas discharged from residue incineration. The present work implies that biomass as addictive holds great potential in the industrial dewatering and pyrolysis of oil-containing sludge.

Optimal dewatering schemes in the foundation design of an electronuclear plant

International Nuclear Information System (INIS)

Galeati, G.; Gambolati, G.

1988-01-01

A three-dimensional finite element model combined with an optimization approach based on linear mixed integer programming is developed and applied to assist in the design of the dewatering system for the electronuclear plant to be built by the Italian Electric Agency (ENEL) in Trino Vercellese, northwestern Italy. The foundations site is encompassed by a 25- to 35-m deep plastic wall with the purpose of protecting the unconfined aquifer from the significant water table lowering required by the construction project. To reduce further the propagation of the depression cone a large amount of the water pumped out is reinjected through ad hoc recharge ditches. The finite element optimization model includes both the natural and the artificial constraints and provides several optimal withdrawal strategies for the dewatering system design concerning the distribution of the abstraction wells and the corresponding pumping rates. Physical and economical objective functions are explored and the related solutions are discussed

Vibrating membrane filtration as improved technology for microalgae dewatering

OpenAIRE

Nurra, C.; Clavero, E.; Salvadó, J.; Torras, C.

2014-01-01

10.1016/j.biortech.2014.01.115 The effect of shear-enhanced filtration by vibratory process in microalgae dewatering is presented in this paper. The aim of this research was to investigate the technical performance and improvement of vibrating membrane filtration compared with conventional tangential cross-flow filtration in microalgae concentration. An industrial-scale available commercial set-up was used. Several membrane materials as polyethersulfone, polyacrylonitrile, etc., and mean ...

Antecedentes e consequências de satisfação dos alunos de graduação com o EAD: um estudo de caso na Unisinos

OpenAIRE

Silva, Diego

2010-01-01

A educação superior privada no Brasil, especialmente na modalidade de Ensino a Distância (EAD), tem tido um grande crescimento nos últimos anos. Com o aumento do número de novos alunos e novas instituições ofertando o EAD, cresceu também a preocupação da sociedade e das próprias instituições em avaliar a satisfação de seus alunos. Na área de marketing a temática da satisfação com seus antecedentes e consequências continua sendo um dos assuntos mais pesquisados e discutidos. Esta dissertação, ...

Ensino da oralidade em Língua Estrangeira na EaD através de programas de comunicação síncrona. L2 speech teaching in Distance Education (EaD through synchronous communication softwares

Directory of Open Access Journals (Sweden)

Estivalet, Gustavo L.

2014-11-01

Full Text Available From the increasing growth of foreign language courses in distance education (EaD, information and communication technology (TIC have been playing a key role for the success of teaching and learning of speaking skills. Hence, synchronous communication softwares such as MSN, GoogleTalk, Skype, Voip, Dim-Dim, VZO Chat, Facebook, among others, have become essential tools for developing this skill in the interaction between students and teachers. Thus, this paper a makes a brief theoretical review of these softwares’ use in teaching speaking skills, b evaluates their use in the UFSC undergraduate distance course on Literature – Bachelor in English Language Teaching, and c discusses the use of synchronous communication softwares for teaching foreign languages in distance education. The adopted methodology included 1 observation on the use of these softwares during the course, 2 a questionnaire answered by the students, and 3 interviews with the teachers. It was observed that these softwares were used mostly in evaluation situations and that there is a demand from the students for broader interaction in foreign language through these tools in a didactic manner. Therefore, in order to develop speaking skills in foreign language in distance education, it is necessary an effective teaching practice through synchronous communication softwares. A partir do grande crescimento dos cursos de línguas estrangeiras (LE na educação a distância (EaD, as tecnologias de informação e comunicação (TIC passaram a desempenhar um papel fundamental nos processos de ensino e aprendizagem da oralidade em LE. Logo, os programas de comunicação síncrona, como MSN, GoogleTalk, Skype, Voip, Dim-Dim, VZO Chat, Facebook, entre outros, tornaram-se ferramentas essenciais na interação entre alunos e professores no desenvolvimento dessa habilidade. Este artigo realiza a uma breve revisão teórica da utilização desses programas no ensino da oralidade em LE, b avalia

46 CFR 28.815 - Bilge pumps, bilge piping, and dewatering systems.

Science.gov (United States)

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Bilge pumps, bilge piping, and dewatering systems. 28... REQUIREMENTS FOR COMMERCIAL FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.815 Bilge pumps, bilge... fixed, self priming, powered, bilge pump, having a minimum capacity rating of 50 gallons per minute...

Physical, chemical and dewatering characteristics of Ba/RaSO4 sludges from uranium milling

International Nuclear Information System (INIS)

Skeaff, J.M.; Campbell, H.W.

1980-01-01

There is concern that long-term environmental pollution caused by radionuclide-bearing acid drainage could occur upon the abandonment of uranium tailings areas. One source of dissolved radionuclides could be the Ba/RaSO 4 sludges formed in most tailings ponds. Prior to discharge to open watercourses, uranium tailings decants are usually treated with barium chloride to coprecipitate dissolved radium. The resulting sludge is allowed to settle in ponds, the size and retention time of which will depend on the mine site. It may be necessary for environmental reasons to remove these sludges for permanent disposal. CANMET has awarded a contract to Kilborn Ltd. of Toronto to study methods for the recovery and dewatering of these sludges. To provide data for the Kilborn contract on the physical, chemical and dewatering of Ba/RaSO 4 sludges presently being produced at uranium mine/mill sites, samples were taken from the operational settling ponds at Rio Algom Mines Ltd., Elliot Lake. Dewatering characterization has also been conducted on two pilot plant facility sludges, one produced at the Wastewater Technology Centre's pilot plant at Rio Algom Mines, and the other from the pilot scale settling ponds designed by James F. MacLaren Ltd. for Rio Algom. The chemical and radionuclide analyses for the CANMET sludge are also reported

Demonstration of FBRM as process analytical technology tool for dewatering processes via CST correlation.

Science.gov (United States)

Cobbledick, Jeffrey; Nguyen, Alexander; Latulippe, David R

2014-07-01

The current challenges associated with the design and operation of net-energy positive wastewater treatment plants demand sophisticated approaches for the monitoring of polymer-induced flocculation. In anaerobic digestion (AD) processes, the dewaterability of the sludge is typically assessed from off-line lab-bench tests - the capillary suction time (CST) test is one of the most common. Focused beam reflectance measurement (FBRM) is a promising technique for real-time monitoring of critical performance attributes in large scale processes and is ideally suited for dewatering applications. The flocculation performance of twenty-four cationic polymers, that spanned a range of polymer size and charge properties, was measured using both the FBRM and CST tests. Analysis of the data revealed a decreasing monotonic trend; the samples that had the highest percent removal of particles less than 50 microns in size as determined by FBRM had the lowest CST values. A subset of the best performing polymers was used to evaluate the effects of dosage amount and digestate sources on dewatering performance. The results from this work show that FBRM is a powerful tool that can be used for optimization and on-line monitoring of dewatering processes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Dewatering behavior of fine oil sands tailings : A summary of laboratory results

NARCIS (Netherlands)

Yao, Y.; van Tol, A.F.; van Paassen, L.A.; Vardon, P.J.; Sego, D.C.; Wilson, G.W.; Beier, N.A.

2016-01-01

To evaluate the disposal technology for fine oil sands tailings, the appropriate engineering properties of the tailings should be ascertained. A laboratory study was conducted by Delft University of Technology (the Netherlands) on the geotechnical properties and dewatering behavior of the fine oil

Fundamental study for improvement of dewatering of fine coal/refuse. Annual report, August 1982-August 1983

Energy Technology Data Exchange (ETDEWEB)

Chiang, S.H.; Klinzing, G.E.; Morsi, B.J.; Tierney, J.W.; Adams, J.; Bhat, N.; Binkley, T.; Chi, S.M.; Kakwani, R.; Qamar, I.

1983-09-01

The overall objective of the study is to seek improved methods of dewatering through a better understanding of the filtration and post-filtration processes. As a first step, efforts have been focused on the mechanism of dewatering in terms of basic properties of coal (and refuse) particles and microstructures of filter cakes, and their relations to filtration rate and final moisture content. Pittsburgh seam-Bruceton Mine coal was used as a base coal with experiments also being conducted with Upper Freeport and Illinois No. 6 coals. During the past year, filter cakes from the above coals with widely varied size ranges were micrographically characterized. The effects of a number of surface active agents and of entrapped air bubbles on the filter cake properties were also studied. A module of the network model for calculating single phase permeabilities was completed and tested. The report is divided into four parts: summary and deliverables; work forecast for the 1983-84; detailed descriptions of technical progress for particle/filter cake characterization; theoretical modeling, and enhanced dewatering methods; and appendices. 11 references, 35 figures, 11 tables.

Isolation and Characterization of Polyacrylamide-Degrading Bacteria from Dewatered Sludge

Directory of Open Access Journals (Sweden)

Feng Yu

2015-04-01

Full Text Available Polyacrylamide (PAM is a water-soluble polymer that is widely used as a flocculant in sewage treatment. The accumulation of PAM affects the formation of dewatered sludge and potentially produces hazardous monomers. In the present study, the bacterial strain HI47 was isolated from dewatered sludge. This strain could metabolize PAM as its sole nutrient source and was subsequently identified as Pseudomonas putida. The efficiency of PAM degradation was 31.1% in 7 days and exceeded 45% under optimum culture condition (pH 7.2, 39 °C and 100 rpm. The addition of yeast extract and glucose improved the bacterial growth and PAM degradation. The degraded PAM samples were analyzed by gel-filtration chromatography, Fourier transform infrared and high-performance liquid chromatography. The results showed that high-molecular-weight PAM was partly cleaved to small molecular oligomer derivatives and part of the amide groups of PAM had been converted to carboxyl groups. The biodegradation did not accumulate acrylamide monomers. Based on the SDS-PAGE and N-terminal sequencing results, the PAM amide groups were converted into carboxyl groups by a PAM-induced extracellular enzyme from the aliphatic amidase family.

Permanganate/bisulfite (PM/BS) conditioning-horizontal electro-dewatering (HED) of activated sludge: Effect of reactive Mn(III) species.

Science.gov (United States)

Guo, Xinxin; Wang, Yili; Wang, Dongsheng

2017-11-01

A novel activated sludge (AS) conditioning method through permanganate/bisulfate (PM/BS) process was proposed. The method involved a new conditioner of reactive Mn(III) intermediate. Moreover, a Mn(III) conditioning-horizontal electro-dewatering (Mn(III) C-HED) process was established to improve AS dewatering performance. Underlying mechanisms were unraveled by investigating changes in physicochemical characteristics, scanning electron microscope (SEM) morphology, and transformation of water and organic matters. The optimum dewatering conditions for Mn(III) C-HED process with the final water content of 86.94% were determined as the combination of KMnO 4 0.01 mol/L AS and NaHSO 3 0.05 mol/L AS at 20 V for 120 min. Results showed that Mn(III) C-HED process effectively reduced free water and bound water with the corresponding removal ratios of 51.68% and 87.62% at the anode-side as well as 36.55% and 85.08% at the cathode-side, respectively. During the PM/BS process, the produced Mn(III), Mn 2+ , and MnO 2 exerted chemical and physical effects on AS conditioning and dewatering. Mn(III) disintegrated extracellular polymeric substances (EPS) fractions and cells in AS, as well as induced partial bound water release. Additionally, flocculation effect induced by Mn 2+ and MnO 2 skeleton building also benefited AS dewatering. AS cells were further disrupted under the effect of a horizontal electric field. Accordingly, EPS within the AS matrix was solubilized, tightly bound (TB)-EPS or loosely bound (LB)-EPS was converted to their corresponding outer EPS fractions, and AS dewaterability improved. Additionally, changes in pH and temperature at HED stage damaged the AS cells and changed the floc properties, thereby leading to easy separation of liquid and AS particles. Copyright © 2017 Elsevier Ltd. All rights reserved.

Electroacoustic analysis, design, and implementation of a small balanced armature speaker.

Science.gov (United States)

Bai, Mingsian R; You, Bo-Cheng; Lo, Yi-Yang

2014-11-01

This paper presents a new design and implementation of a balanced armature speaker (BAS), which is composed of permanent magnetic circuits, a moving armature, and a coil. The armature rocks about a pivot with the coil at one end and the permanent magnet on another. A magnetic circuit analysis is conducted for the designed BAS to formulate the force factor, which is required for modeling the coupling between the electrical and mechanical systems. In addition, an electromechanoacoustical analogous circuit is established for the BAS, which bears the same structure as the moving coil loudspeaker, except that the force factor is different. A hybrid model, which combines the lumped parameter model in the electrical and acoustical domains with a finite element model in the mechanical domain, is developed to model the high-frequency response because of the high-order modes of the membrane, the drive rod, and the armature. The electroacoustic analysis is experimentally verified. The results indicate that the sound pressure response that is simulated using the hybrid model is in superior agreement with the measured response to that simulated using the lumped parameter model.

Toward wideband steerable acoustic metasurfaces with arrays of active electroacoustic resonators

Science.gov (United States)

Lissek, Hervé; Rivet, Etienne; Laurence, Thomas; Fleury, Romain

2018-03-01

We introduce an active concept for achieving acoustic metasurfaces with steerable reflection properties, effective over a wide frequency band. The proposed active acoustic metasurface consists of a surface array of subwavelength loudspeaker diaphragms, each with programmable individual active acoustic impedances allowing for local control over the different reflection phases over the metasurface. The active control framework used for controlling the reflection phase over the metasurface is derived from the Active Electroacoustic Resonator concept. Each unit-cell simply consists of a current-driven electrodynamic loudspeaker in a closed box, whose acoustic impedance at the diaphragm is judiciously adjusted by connecting an active electrical control circuit. The control is known to achieve a wide variety of acoustic impedances on a single loudspeaker diaphragm used as an acoustic resonator, with the possibility to shift its resonance frequency by more than one octave. This paper presents a methodology for designing such active metasurface elements. An experimental validation of the achieved individual reflection coefficients is presented, and full wave simulations present a few examples of achievable reflection properties, with a focus on the bandwidth of operation of the proposed control concept.

A novel acrylamide-free flocculant and its application for sludge dewatering.

Science.gov (United States)

Lu, Lianghua; Pan, Zhida; Hao, Nan; Peng, Wenqing

2014-06-15

In the present research, copolymers of methyl acrylate (MA) with anionic or cationic monomers were synthesized via emulsion polymerization, and used as sludge dewatering aids in wastewater treatment. The copolymerization of different stoichiometry of two monomers afforded a variety of water soluble copolymers with charge densities ranging from 40% to 80%, which align with the charge density of current flocculant products. These copolymers resemble current commercial products, but provide a greener solution by eliminating acrylamide monomer, which is a suspected carcinogen. High molecular weight copolymers were achieved by applying powder-like synthesis process with intrinsic viscosity of final products as high as 12.98 dl/g for anionic flocculant and 10.74 dl/g for cationic flocculant. The copolymers of methyl acrylate and [2-(Acryloyloxy)ethyl]trimethylammonium chloride (AETAC) with 55% charge density exhibited comparable performance in clay settling test, real water jar test, and sludge dewatering, when compared to AM-based commercial product in the real wastewater treatment application. Copyright © 2014 Elsevier Ltd. All rights reserved.

Dewatering properties of differently treated sewage sludge

International Nuclear Information System (INIS)

Zehnder, H.J.

1977-01-01

A study on dewatering properties of radiosterilized sewage sludge of different type and origin was carried out. For comparison, also heat-treated (pasteurized) sludge was investigated. The specific filtration resistance of irradiated sewage sludge was lowered in all types of sludge examined. In general, pasteurization increased this parameter. The settling properties of irradiated digested sewage sludge was slightly improved, mainly in the first hours after treatment. Microbial effects may mask the real sedimentation relations especcially in aerobically stabilized sludges. A pasteurization treatment of sewage sludge caused an increased content of soluble substances and suspended particles in the supernatant water. The supernatant water from irradiated sludge showed a smaller increase

Equations for nickel-chromium wire heaters of column transfer lines in gas chromatographic-electroantennographic detection (GC-EAD).

Science.gov (United States)

Byers, John A

2004-05-30

Heating of chromatographic columns, transfer lines, and other devices is often required in neuroscience research. For example, volatile compounds passing through a capillary column of a gas chromatograph (GC) can be split, with half exiting the instrument through a heated transfer line to an insect antenna or olfactory sensillum for electroantennographic detector (GC-EAD) recordings. The heated transfer line is used to prevent condensation of various chemicals in the capillary that would otherwise occur at room temperature. Construction of such a transfer line heater is described using (80/20%) nickel-chromium heating wire wrapped in a helical coil and powered by a 120/220 V ac rheostat. Algorithms were developed in a computer program to estimate the voltage at which a rheostat should be set to obtain the desired heater temperature for a specific coil. The coil attributes (radius, width, number of loops, or length of each loop) are input by the user, as well as AWG size of heating wire and desired heater temperature. The program calculates total length of wire in the helix, resistance of the wire, amperage used, and the voltage to set the rheostat. A discussion of semiochemical isolation methods using the GC-EAD and bioassays is presented.

REDES TECNOLÓGICAS APLICADAS EM EaD

Directory of Open Access Journals (Sweden)

Suélly Lima dos Santos

2011-08-01

Full Text Available Com o advento da internet e o aparecimento das novas tecnologias educacionais, conjunto de informações e comunicações (telefone, internet, rádio, vídeo, computador e televisão, ultrapassaram as fronteiras das quatro paredes da sala de aula, surgindo ambientes virtuais direcionadas à ampliação da participação dos serviços públicos relacionados ao ensino. À educação e à formação técnica e profissional permitiu-se o aumento da interatividade através da tecnologia, promovendo maneiras de acesso ao aluno utilizando computadores e/ou dispositivos móveis que viabiliza a Educação à Distância (EaD. Devido o grande crescimento do ensino à distância, as instituições já utilizam redes de dados para ampliar o acesso de aprendizagem. Com este espantoso aumento das redes, e da acelerada transmissão de informações aprender como elas funcionam é muito importante, além do mais usando a própria tecnologia para este fim. Como conclusão deste trabalho as mudanças relâmpadas da grande disponibilidade de dados no ambiente virtual é de enorme valia para o processo ensino-aprendizado.

(DE FORMANDO O EDUCADOR: UMA DISCUSSÃO TEÓRICA ACERCA DO PROFESSOR E TUTOR NA EAD

Directory of Open Access Journals (Sweden)

Cláudia Coelho Hardagh

2017-06-01

Full Text Available O artigo objetiva contribuir com a reflexão da vivência das pesquisadoras na educação, em diferentes modalidades (presencial e a distância aliada a elementos teóricos, para compreender o processo de inserção do professor universitário nas aulas de modalidade a distancia (EaD, no período de expansão (2010-2016 dos cursos totalmente EaD ou semi-presenciais, em Instituições de Ensino Superior. A questão problematizadora é até que ponto a nossa prática docente, na educação a distância, provoca o distanciamento do professor da sua práxis? Partimos do pressuposto de que é necessário entendermos a dimensão do processo de proletarização, alienação, distanciando do professor de sua práxis, ou seja, de sua autonomia na criação de aulas, gestão do conteúdo e na relação humana com seus alunos para avaliar as consequências para o educador. Discute-se, por fim, o contexto da cibercultura que exige uma nova prática em espaço e tempo virtual para a educação on line.

An environmental isotope study of a major dewatering operation at Sishen mine, northern Cape Province

International Nuclear Information System (INIS)

Verhagen, B.T.; Smith, P.E.; Dziembowski, Z.; Oosthuizen, J.H.

1978-01-01

Geohydrological studies using environmental isotopes of the Sishen iron ore mine were started after major rainfalls in 1973/74 produced flooding of the open cast workings. The mine is underlain by dolomite which has been extensively karstified and geohydrologically compartmentalized by several dykes. Major dewatering takes place in a pit called Hill 2 by pumping an array of large diameter boreholes at a combined rate of 2000 m 3 h -1 . The probable recharge areas (dolomites, superficial Kalahari Beds) were isotopically surveyed to assess their relative importance to the dewatering problem. Several major pumping outlets at the mine were regularly sampled for isotopic and chemical analysis and from the data a preliminary mixing model is proposed. The data also show that with the total pumped volume up to March 1978, no very recent (i.e. post bomb) water has reached the dewatering points. On this basis a minimum storage of 0.75 x 10 8 m 3 is derived compared to a classical calculation of 10 8 m 3 for the compartment. Isotopic composition and response differ for waters on either side of a dyke crossing the mining area, corroborating classical evidence suggesting that the dyke acts as an aquiclude. (orig.) [de

An environmental isotope study of a major dewatering operation at Sishen mine, northern Cape Province

International Nuclear Information System (INIS)

Verhagen, B.Th.; Smith, P.E.; Oosthuizen, J.H.

1979-01-01

Geohydrological studies using environmental isotopes of the Sishen iron ore mine were started after major rainfalls in 1973/74 produced flooding of the open cast workings. The mine is underlain by dolomite which has been extensively karstified and geohydrologically compartmentalized by several dykes. Major dewatering takes place in a pit called Hill 2 by pumping an array of large-diameter boreholes at a combined rate of 2000m 3 h -1 . The probable recharge areas (dolomites, superficial Kalahari Beds) were isotopically surveyed to assess their relative importance to the dewatering problem. Several major pumping outlets at the mine were regularly sampled for isotopic and chemical analysis and from the data a preliminary mixing model is proposed. The data also show that, with the total pumped volume up to March 1978, no very recent (i.e. post-bomb) water has reached the dewatering points. On this basis a minimum storage of 0.75x10 8 m 3 is derived compared with a classical calculation of 10 8 m 3 for the compartment. Isotopic composition and response differ for waters on either side of a dyke crossing the mining area, corroborating classical evidence suggesting that the dyke acts as an aquiclude. (author)

Design of the Nonlinear Pin Rubber Forming Equipment Integrating the Functions of Extruding, Dewatering, Drying & Expanding

Directory of Open Access Journals (Sweden)

Yuefeng Yuan

2014-12-01

Full Text Available The top priority of car-tire suppliers is to improve wetland grip force of the using tires, reduce the rolling resistance and the rolling noise of tires. It is urgent for the tire industry to research and develop high-performance tires to solve the above problems. They must use the high- performance synthetic rubber and auxiliary rubber to develop the most advanced manufacturing technologies and equipment. Silica, a kind of important tire auxiliary rubber, can significantly reduce the rolling resistance of tires, improve the grip force and properties resistant to ice, wetness or slippery of tires. In this paper, based on the conventional tire rubber forming technologies of extrusion, dewatering, drying and expanding, a study is made on the conical screw, the dewatering barrel, the drying barrel, the pin layout scheme, the expanding die head, cutter and the control system. The nonlinear pin rubber forming equipment integrating the functions of extrusion, dewatering, drying and expanding is designed and applied to tire auxiliary rubber forming. The experiment shows that the forming device can realize the one-step forming, with high forming efficiency, low cost and less labor.

Device for dewatering of raw biomass. Anordning foer avvattning och uppluckring av raa biomassa

Energy Technology Data Exchange (ETDEWEB)

Kubat, J; Aabom, J J.V.; Klason, T C.F.; Bultzingsloewen, F von

1993-09-27

This invention concerns a device for loosening of raw biomass through roll dewatering. It is primarily applicable for comminuted and milled raw wood. The invention is of special interest for the production of pulverized wood fuel

A comparison of the economic benefits of centralized and distributed model predictive control strategies for optimal and sub-optimal mine dewatering system designs

International Nuclear Information System (INIS)

Romero, Alberto; Millar, Dean; Carvalho, Monica; Maestre, José M.; Camacho, Eduardo F.

2015-01-01

Mine dewatering can represent up to 5% of the total energy demand of a mine, and is one of the mine systems that aim to guarantee safe operating conditions. As mines go deeper, dewatering pumping heads become bigger, potentially involving several lift stages. Greater depth does not only mean greater dewatering cost, but more complex systems that require more sophisticated control systems, especially if mine operators wish to gain benefits from demand response incentives that are becoming a routine part of electricity tariffs. This work explores a two stage economic optimization procedure of an underground mine dewatering system, comprising two lifting stages, each one including a pump station and a water reservoir. First, the system design is optimized considering hourly characteristic dewatering demands for twelve days, one day representing each month of the year to account for seasonal dewatering demand variations. This design optimization minimizes the annualized cost of the system, and therefore includes the investment costs in underground reservoirs. Reservoir size, as well as an hourly pumping operation plan are calculated for specific operating environments, defined by characteristic hourly electricity prices and water inflows (seepage and water use from production activities), at best known through historical observations for the previous year. There is no guarantee that the system design will remain optimal when it faces the water inflows and market determined electricity prices of the year ahead, or subsequent years ahead, because these remain unknown at design time. Consequently, the dewatering optimized system design is adopted subsequently as part of a Model Predictive Control (MPC) strategy that adaptively maintains optimality during the operations phase. Centralized, distributed and non-centralized MPC strategies are explored. Results show that the system can be reliably controlled using any of these control strategies proposed. Under the operating

Effect of TiO2 nanoparticles on UASB biomass activity and dewatered sludge.

Science.gov (United States)

Yadav, Tushar; Mungray, Alka A; Mungray, Arvind K

2017-02-01

The accumulation of the nanowastes in the wastewater treatment plants has raised several concerns; therefore, it is an utmost priority to study the nanoparticle (NP) toxicity in such systems. In this work, the effect of TiO 2 NPs on up-flow anaerobic sludge blanket (UASB) microflora and their photocatalytic effect on dewatered sludge were studied. We observed 99.98% removal of TiO 2 NPs by sludge biomass within 24 h, though negligible toxicity was found up to 100 mg/L TiO 2 concentration on extracellular polymeric substances (EPS), volatile fatty acid and biogas generation. The low toxicity corresponds to the agglomeration of TiO 2 NPs in UASB sludge. Alterations in dewatered sludge biochemical composition and increase in cell damage were observed upon exposure to sunlight as evidenced by FTIR and fluorescent microscopy, respectively. Results suggest the negligible toxicity of TiO 2 NPs on UASB biomass activity; however, once exposed to open environment and sunlight, they may exert detrimental effects.

Active field control (AFC) -electro-acoustic enhancement system using acoustical feedback control

Science.gov (United States)

Miyazaki, Hideo; Watanabe, Takayuki; Kishinaga, Shinji; Kawakami, Fukushi

2003-10-01

AFC is an electro-acoustic enhancement system using FIR filters to optimize auditory impressions, such as liveness, loudness, and spaciousness. This system has been under development at Yamaha Corporation for more than 15 years and has been installed in approximately 50 venues in Japan to date. AFC utilizes feedback control techniques for recreation of reverberation from the physical reverberation of the room. In order to prevent coloration problems caused by a closed loop condition, two types of time-varying control techniques are implemented in the AFC system to ensure smooth loop gain and a sufficient margin in frequency characteristics to prevent instability. Those are: (a) EMR (electric microphone rotator) -smoothing frequency responses between microphones and speakers by changing the combinations of inputs and outputs periodically; (b) fluctuating-FIR -smoothing frequency responses of FIR filters and preventing coloration problems caused by fixed FIR filters, by moving each FIR tap periodically on time axis with a different phase and time period. In this paper, these techniques are summarized. A block diagram of AFC using new equipment named AFC1, which has been developed at Yamaha Corporation and released recently in the US, is also presented.

Environmental control of drilling mud discharge through dewatering in cold weather climates: effect of ambient temperature

Energy Technology Data Exchange (ETDEWEB)

Wojtanowicz, A. K. [Louisiana State Univ., Baton Rouge, LA (United States); Ye, Y. [Jianghan Petroleum Institute, Beijing, (China)

1998-05-01

Results of an experimental study of the effects of drilling mud temperature upon dewatering performance at various temperatures were presented. Three temperature ranges (from flowline temperature to room temperature, from room temperature to freezing point, and freeze/thaw, i.e. from -20 degrees C to 12 degrees C) were considered. Both unweighted and weighted fresh water muds and weighted salt water mud were tested using a sealed laboratory batch reactor, to prevent rapid vaporization of separated water at temperatures above 60 degrees C. Deep freezing was achieved by using ice or ice-salt baths. Net water removal was measured with a bench-top plate press under constant expression pressure of 270 kPa. Results showed that the freeze/thaw treatment process proved to be very effective, enhancing water removal by 34 to 39 per cent, and reducing waste mud volume by 64 to 72 per cent. No advantage to dewatering hot drilling mud from active systems was observed at temperatures above 21 degrees C. It was suggested that at temperatures under 21 degrees C, the waste drilling mud diverted from an active system should be dewatered when its temperature is still over 40 degrees C. to reduce the amount of chemicals needed for separation enhancement. 14 refs., 4 tabs., 4 figs.

Qual o impacto do conhecimento de informática no desempenho acadêmico dos alunos de EaD?

Directory of Open Access Journals (Sweden)

Eduardo de Paula e Silva Chaves

2013-01-01

Full Text Available Com a globalização e a difusão da internet ganhou impulso extraordinário, nos últimos anos, a educação à distância (EAD, por meio de aulas transmitidas através de websites e atividadescumpridas pelos alunos em seus próprios computadores. O EAD vem facilitar o acesso ao ensino para as pessoas que trabalham ou possuem baixo poder aquisitivo, devido ao seu custo reduzido e a exibilidades de horários. Apesar de existir há mais de 150 anos no mundo, somente nas últimas décadas a educação à distância se tornou alvo de estudos e pesquisas acadêmicas, de forma sistematizada. Neste contexto, o objetivo desta pesquisa é avaliar o impacto do conhecimentoem informática no desempenho acadêmico dos alunos de EAD da Faculdade COC. Foi realizada uma pesquisa exploratória não probabilística na Faculdade Interativa COC – EAD, Pólo Lafaiete – Ribeirão Preto. Tal pesquisa consistiu em um questionário com 21 questões dicotômicas qualitativas, relativas ao grau de conhecimento e domínio das tecnologias de informação e ensino à distância, disponibilidade de acesso a estas tecnologias, além do sexo e desempenho acadêmico(média ponderada e nota no último módulo. Os dados foram tabulados, sendo consideradas duas variáveis principais: desempenho acadêmico, representado pela nota do último módulo; e conhecimento em informática, representado pela somatória das questões relativas a este assunto. Os dados foram analisados estatisticamente, sendo a correlação entre as duas variáveis consideradas analisada pelo teste de Correlação de Pearson. Foram analisadas as entrevistas de 54respondentes do curso de Administração (44,45% do sexo masculino e 55,55% sexo feminino. O coeficiente de correlação r=0,303 indica que há uma correlação significativa entre o desempenho acadêmico dos alunos (nota e seu conhecimento em informática, ou seja, quanto maior o domínio da informática melhores as notas obtidas por estes alunos

Qual o impacto do conhecimento de informática no desempenho acadêmico dos alunos de EaD?

Directory of Open Access Journals (Sweden)

Eduardo de Paula e Silva Chaves

2013-10-01

Full Text Available Com a globalização e a difusão da internet ganhou impulso extraordinário, nos últimos anos, a educação à distância (EAD, por meio de aulas transmitidas através de websites e atividades cumpridas pelos alunos em seus próprios computadores. O EAD vem facilitar o acesso ao ensino para as pessoas que trabalham ou possuem baixo poder aquisitivo, devido ao seu custo reduzido e a flexibilidades de horários. Apesar de existir há mais de 150 anos no mundo, somente nas últimas décadas a educação à distância se tornou alvo de estudos e pesquisas acadêmicas, de forma sistematizada. Neste contexto, o objetivo desta pesquisa é avaliar o impacto do conhecimento em informática no desempenho acadêmico dos alunos de EAD da Faculdade COC. Foi realizada uma pesquisa exploratória não probabilística na Faculdade Interativa COC – EAD, Pólo Lafaiete – Ribeirão Preto. Tal pesquisa consistiu em um questionário com 21 questões dicotômicas qualitativas, relativas ao grau de conhecimento e domínio das tecnologias de informação e ensino à distância, disponibilidade de acesso a estas tecnologias, além do sexo e desempenho acadêmico (média ponderada e nota no último módulo. Os dados foram tabulados, sendo consideradas duas variáveis principais: desempenho acadêmico, representado pela nota do último módulo; e conhecimento em informática, representado pela somatória das questões relativas a este assunto Os dados foram analisados estatisticamente, sendo a correlação entre as duas variáveis consideradas analisada pelo teste de Correlação de Pearson. Foram analisadas as entrevistas de 54 respondentes do curso de Administração (44,45% do sexo masculino e 55,55% sexo feminino. O coeficiente de correlação r=0,303 indica que há uma correlação significativa entre o desempenho acadêmico dos alunos (nota e seu conhecimento em informática, ou seja, quanto maior o domínio da informática melhores as notas obtidas por estes

Os benefícios das Tecnologias de Informação e Comunicação (TIC no processo de Educação a Distância (EAD

Directory of Open Access Journals (Sweden)

Suelen Conceição Farias

2013-08-01

Full Text Available Este artigo apresenta, com base na literatura pesquisada acerca do tema, o conceito, as características e os benefícios proporcionados pelo uso das Tecnologias de Informação e Comunicação (TIC no processo de Educação a Distância (EAD, de maneira a facilitar o processo ensino-aprendizagem, assim como incentivar a disseminação de informações e experiências entre alunos e professores e/ou tutores. Também mostra exemplos de ferramentas tecnológicas utilizadas na EAD com o intuito de favorecer tal comunicação.

Hydrothermal treatment coupled with mechanical expression at increased temperature for excess sludge dewatering: the dewatering performance and the characteristics of products.

Science.gov (United States)

Wang, Liping; Li, Aimin

2015-01-01

Hydrothermal treatment coupled with mechanical expression at increased temperature in two separate cells respectively is effective for the dewatering of excess sludge with low energy consumption. The objectives of this study were to evaluate the dewatering performance and the characteristics of obtained products (hydrothermal sludge, hydrochar and filtrate). The results showed that harsher hydrothermal treatment (temperature from 120 to 210 °C and residence time from 10 to 90 min) led to greater water removal (from 7.44 to 96.64% reduction of total water) and mechanical pressure became less significant as it increased. The whole expression stage was completely described by the modified Terzaghi-Voigt rheological model. The role of tertiary consolidation stage in the water removal was reduced with hydrothermal treatment being stronger. The hydrothermal treatment is mainly a devolatilization process. The observed changes in H/C and O/C for hydrothermal sludge suggested dehydration was the major reaction mechanism and decarboxylation only occurred significantly at higher temperature. The higher heating value correlated well with carbon content of sludge, which was increased by 4.8% for hydrothermal sludge at 210 °C for 60 min and significantly decreased by 15.4% for hydrochar after 6.0 MPa for 20 min. The solubilization and decomposition of proteins, polysaccharides and DNA were determined to be temperature and residence time dependent. The improvement of dewaterability was closely correlated to the variation of these biopolymers. The filtrates collected above 150 °C were found to be acidic. The increase of humic substances and the melanoidins formed by Maillard reaction were largely responsible for the filtrate color.

Chitosan use in chemical conditioning for dewatering municipal-activated sludge.

Science.gov (United States)

Zemmouri, H; Mameri, N; Lounici, H

2015-01-01

This work aims to evaluate the potential use of chitosan as an eco-friendly flocculant in chemical conditioning of municipal-activated sludge. Chitosan effectiveness was compared with synthetic cationic polyelectrolyte Sedipur CF802 (Sed CF802) and ferric chloride (FeCl₃). In this context, raw sludge samples from Beni-Messous wastewater treatment plant (WWTP) were tested. The classic jar test method was used to condition sludge samples. Capillary suction time (CST), specific resistance to filtration (SRF), cakes dry solid content and filtrate turbidity were analyzed to determine filterability, dewatering capacity of conditioned sludge and the optimum dose of each conditioner. Data exhibit that chitosan, FeCl₃and Sed CF802 improve sludge dewatering. Optimum dosages of chitosan, Sed CF802 and FeCl₃allowing CST values of 6, 5 and 9 s, were found, respectively, between 2-3, 1.5-3 and 6 kg/t ds. Both polymers have shown faster water removal with more permeable sludge. SRF values were 0.634 × 10¹², 0.932 × 10¹² and 2 × 10¹² m/kg for Sed CF802, chitosan and FeCl₃respectively. A reduction of 94.68 and 87.85% of the filtrate turbidity was obtained with optimal dosage of chitosan and Sed CF802, respectively. In contrast, 54.18% of turbidity abatement has been obtained using optimal dosage of FeCl₃.

Network model for fine coal dewatering. Part I. The model

Energy Technology Data Exchange (ETDEWEB)

Qamar, I.; Tierney, J.W.; Chiang, S.H.

1985-08-01

There is a body of well established research in filtration and related subjects, but much of it has been empirical - based on correlations from experimental data. This approach has the disadvantage that it lacks generality, and it is difficult to predict the behavior of new or different systems. A more general method for studying dewatering is needed-one which will include the microscopic characteristics of the filter cake, which, like other porous media, contains a complicated network of interconnected pores through which the fluid must flow. These pores play an important role in dewatering because they give rise to capillary forces when one fluid is displacing another. In this report, we describe a network model which we believe satisfies these requirements. In the main body of this report, the model is described in detail. Background information is given where appropriate, and a brief description is given of the experimental work being done in our laboratories to verify the model. A detailed description of the experimental procedures and results is given in other DOE reports. The computer programs which are needed to solve the model are described in detail in the Appendices and are accompanied by flow charts, sample problems, and sample outputs. Sufficient detail is given in order to use the model programs on other computer systems. 32 refs., 7 figs., 5 tabs.

Procedure of dewatering by pressing of biomass pulp, especially a peat cake. Saett att genom pressning avvattna en kaka av biomassa, foeretraedesvis en torvkaka

Energy Technology Data Exchange (ETDEWEB)

Eriksson, S

1988-05-24

The pulp is dewatered by pressing above 90 degrees C, the pulp water being displaced by warmer water under successively increased pressure. A device designed like a closed washing press is used. The pulp is subjected to dewatering, washing or displacement by warmer water and thus heating, and calendering. (O.S.).

Influence of the hydrothermal dewatering on the combustion characteristics of Chinese low-rank coals

International Nuclear Information System (INIS)

Ge, Lichao; Zhang, Yanwei; Xu, Chang; Wang, Zhihua; Zhou, Junhu; Cen, Kefa

2015-01-01

This study investigates the influence of hydrothermal dewatering performed at different temperatures on the combustion characteristics of Chinese low-rank coals with different coalification maturities. It was found that the upgrading process significantly decreased the inherent moisture and oxygen content, increased the calorific value and fixed carbon content, and promoted the damage of the hydrophilic oxygen functional groups. The results of oxygen/carbon atomic ratio indicated that the upgrading process converted the low-rank coals near to high-rank coals which can also be gained using the Fourier transform infrared spectroscopy. The thermogravimetric analysis showed that the combustion processes of upgraded coals were delayed toward the high temperature region, and the upgraded coals had higher ignition and burnout temperature. On the other hand, based on the higher average combustion rate and comprehensive combustion parameter, the upgraded coals performed better compared with raw brown coals and the Da Tong bituminous coal. In ignition segment, the activation energy increased after treatment but decreased in the combustion stage. The changes in coal compositions, microstructure, rank, and combustion characteristics were more notable as the temperature in hydrothermal dewatering increased from 250 to 300 °C or coals of lower ranks were used. - Highlights: • Typical Chinese lignites with various ranks are upgraded by hydrothermal dewatering. • Upgraded coals exhibit chemical compositions comparable with that of bituminous coal. • FTIR show the change of microstructure and improvement in coal rank after upgrading. • Upgraded coals exhibit difficulty in ignition but combust easily. • More evident effects are obtained for raw brown coal with relative lower rank.

Representaciones culturales de países hispanohablantes: una mirada a los recursos visuales en el contexto de EaD

Directory of Open Access Journals (Sweden)

Leandra Cristina de Oliveira

2017-09-01

Full Text Available Con vistas a la relevancia de la discusión sobre cultura en la Lingüística Aplicada, tanto en el ámbito de la enseñanza de lengua materna como de lengua extranjera, direccionamos el diálogo sobre el tema a la enseñanza de español en la Educación a Distancia (EaD. Observando el Curso de Letras Español de la Universidad Federal de Santa Catarina, en la modalidad EaD, objetivamos discutir las representaciones culturales de los países hispanohablantes en las imágenes del Ambiente virtual de la asignatura Lengua Española I. Consonante al objetivo, asentamos la siguiente cuestión: ¿en qué medida las representaciones culturales en las imágenes analizadas contribuyen para la desconstrucción de concepciones reduccionistas y estereotipadas sobre los países hispanohablantes? La respuesta a esta cuestión procede del análisis de las imágenes introductorias de los tópicos de la asignatura citada, fundamentada en bases teóricas de estudios culturales, con especial atención a los conceptos de cultura, identidad y diferencia.

Experimental study of a hybrid electro-acoustic nonlinear membrane absorber

Science.gov (United States)

Bryk, P. Y.; Bellizzi, S.; Côte, R.

2018-06-01

A hybrid electro-acoustic nonlinear membrane absorber working as a nonlinear energy sink (here after named EA-NES) is described. The device is composed of a thin circular visco-elastic membrane working as an essentially cubic oscillator. One face of the membrane is coupled to the acoustic field to be reduced and the other face is enclosed. The enclosure includes a loudspeaker for the control of the acoustic pressure felt by the rear face of the membrane through proportional feedback control. An experimental set-up has been developed where the EA-NES is weakly coupled to a linear acoustic system. The linear acoustic system is an open-ended tube, coupled on one side to the EA-NES by a box, and on the other side to a source loudspeaker by another box. Only sinusoidal forcing is considered. It is shown that the EA-NES is able to perform resonance capture with the acoustic field, resulting in noise reduction by targeted energy transfer, and to operate in a large frequency band, tuning itself passively to any linear system. We demonstrate the ability of the feedback gain defining the active loop to modify the resonance frequency of the EA-NES, which is a key factor to tune the triggering threshold of energy pumping. The novelty of this work is to use active control combined to passive nonlinear transfer energy to improve it. In this paper, only experimental results are analyzed.

As Estratégias de Aprendizagem Autorregulada (SRL no Ensino EAD de Contabilidade

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Thiago Bruno de Jesus Silva

2017-01-01

Full Text Available Os objetivos desta investigação foram identificar quais são as estratégias de aprendizagem autorregulada utilizadas por estudantes de Contabilidade do ensino Educação a Distância (EAD e analisar como essas estratégias poderiam ser explicadas a partir do estágio (semestre do estudante no curso. A amostra da pesquisa compreendeu discentes do curso de graduação em Ciências Contábeis na modalidade de Ensino a Distância de três instituições com polo em Salvador(BA/Brasil. Para análise dos dados, utilizaram-se três procedimentos quantitativos visando alcançar os objetivos específicos, no qual, para identificar as estratégias de aprendizagem autorregulada foi utilizada a estatística descritiva e, para verificar como essas estratégias poderiam ser explicadas a partir do estágio (semestre do estudante no curso, foi alcançada por meio da Análise Fatorial e o uso de testes paramétricos de comparação de médias (teste t. Os achados permitiram inferir que o perfil dos alunos da modalidade de ensino EAD, considerando a autorregulação da aprendizagem, foi de utilização significativa de estratégias de acordo ao modelo proposto pela Zimmerman e Pons (1986, em que há diferenças significativas nas médias dos discentes entre o estágio inicial e final de curso. O estudo contribui com os apontamentos dos órgãos internacionais de contabilidade sobre a aprendizagem ativa e permanente. A investigação proporciona, também, benefício à literatura sobre a modalidade de “Ensino a Distância” e à aprendizagem autorregulada por demonstrar que essa plataforma de ensino pode auxiliar na consecução da independência do aprendizado.

Carta Acuerdo Dirección de EaD - y Dirección SeDiCI

OpenAIRE

Universidad Nacional de La Plata; Dirección de Educación a Distancia, Innovación en el aula y TIC (EAD)

2012-01-01

Establecer un marco de colaboración técnica entre la Dirección de Educación a Distancia Innovación en el aula y TIC (EaD) y el Servicio de Difusión de la Creación Intelectual (SeDiCI) de la UNLP, de modo de potenciar el desarrollo de actividades conjuntas en temas de interés común, aprovechando al máximo los recursos humanos y de infraestructura con los que cuentan. En este contexto crear un Repositorio Abierto de Objetos de Aprendizaje (OA) que permita integrar la producción de la UNLP y ...

Ground movement and deformation due to dewatering and open pit excavation

International Nuclear Information System (INIS)

Liu, B.; Yang, J.; Zhang, J.

1996-01-01

In the application of stochastic medium theory, it is assumed that ground movement process has the property of Markov Process. Based on superposition principle and rock consolidation principle, the ground movement and deformation due to dewatering and open pit excavation can be calculated. The comparison between the field measurements in Morwell Open Pit, Latrobe Valley (Victoria, Australia) and the calculated results shows the validity of the method in this paper. 5 refs

Effect of dewatering on seismic performance of multi-anchor wall due to high ground water level

Science.gov (United States)

Kobayashi, Makoto; Miura, Kinya; Konami, Takeharu; Hayashi, Taketo; Sato, Hiroki

2017-10-01

Previous research reported that the ground water in the backfill of reinforced soil wall made it deteriorate. According to the damage investigation of Great East Earthquake 2011, the reinforced soil structure due to high ground water level by seismic wave were deformed remarkably. Some of them classified ultimate limit state or restorability limit state. However, more than 90% of reinforced soil structure, which suffered from this earthquake, were classified into no damage condition. Therefore, it is necessary that the seismic behaviors of multi-anchor wall due to seepage flow should be clarified in order to adopt the performance-based design in such reinforced soil structure. In this study, a series of centrifugal shaking table tests were conducted to investigate the seismic behavior of multi-anchor wall due to high ground water level. The reinforced drainage pipes were installed into the backfill in order to verify the dewatering effect and additional reinforcement. Furthermore, to check only the dewatering effect, the model tests was carried out with several ground water table that was modeled the case reinforced drainage pipes installed. The test results show unique behavior of reinforced region that moved integrally. This implies that the reinforced region has been behaved as if it became one mass, and this behavior make this structure increase seismic performance. Thus, the effectiveness of dewatering was observed remarkably because of decreasing the inertial force during earthquake.

Improvements in or relating to dewatering of materials

International Nuclear Information System (INIS)

Lane, E.S.; Lyon, C.E.; Simpson, M.P.; Wace, P.F.

1980-01-01

A process is described for the dewatering of a gel precipitated gel body having an open porous network comprising contacting the gel body containing water with an organic liquid capable of extracting water from the gel body thereby to extract water from the gel body, the organic liquid and conditions under which the contacting is effected being chosen such that organic liquid permeates the gel body so as to maintain an open porous network as water is extracted and such that an open porous network remains after removal of organic liquid. Examples are given of the use of the process in the preparation of spherical particles of (U,Th)O 2 and (U,Pu)O 2 . (author)

Effects of gamma-radiation at pilot plant level as compared to effects of pasteurization on the dewatering of sewage sludges

International Nuclear Information System (INIS)

Groneman, A.F.

1975-01-01

Dewatering and disposal of sludge are costly and time consuming processes. At a pilot plant near Munich efforts were made to estimate the effects of ionizing radiation on dewatering characteristics of different sludges, used for recycling in agriculture. The ease with which sludge drains on drying beds and in mechanical devices is reflected in the value of the specific resistance to filtration. A dose of 300 krad, delivered at an average dose rate of 62 krad per hour in the irradiation plant, was effective for disinfection and reduced the specific resistance to filtration in sludges from the waste water works at Geiselbullach and Starnberg from 24.2 x 10 9 sec 2 /g and 18.0 x 10 9 sec 2 /g to 9.7 x 10 9 sec 2 /g and 5.6 x 10 9 sec 2 /g, respectively. These improved dewatering properties were associated with a clear increase of the compressibility of the anaerobically digested sludges. Pasteurization at 70 0 C during 30 minutes drastically deteriorated the dewatering properties, raising the specific resistance to values approximately 4 times as high as the specific resistance in irradiated sludges. Information obtained from filterability tests was confirmed by plant operators who noticed that irradiated sludges dewatered much better than untreated sludges in drying beds. Experimental evidence indicated that the conditioning effect of gamma irradiation persisted for more than 20 days suggesting that permanent changes were induced in the physical-chemical properties of the domestic, anaerobically digested sludges. Measurements of electrophoretic mobilities showed that the negative electrostatic charges of colloidal particles in sludges were reduced by gamma irradiation whereas pasteurization increased this negative electrostatic charge. Evidence indicated that the specific resistance was considerably increased by effects of the recirculating pumping. This pumping is done to obtain a homogeneous irradiation dose for disinfection. Alternative designs for irradiation

Textural evidence for jamming and dewatering of a sub-surface, fluid-saturated granular flow

Science.gov (United States)

Sherry, T. J.; Rowe, C. D.; Kirkpatrick, J. D.; Brodsky, E. E.

2011-12-01

Sand injectites are spectacular examples of large-scale granular flows involving migration of hundreds of cubic meters of sand slurry over hundreds of meters to kilometers in the sub-surface. By studying the macro- and microstructural textures of a kilometer-scale sand injectite, we interpret the fluid flow regimes during emplacement and define the timing of formation of specific textures in the injected material. Fluidized sand sourced from the Santa Margarita Fm., was injected upward into the Santa Cruz Mudstone, Santa Cruz County, California. The sand injectite exposed at Yellow Bank Beach records emplacement of both hydrocarbon and aqueous sand slurries. Elongate, angular mudstone clasts were ripped from the wall rock during sand migration, providing evidence for high velocity, turbid flow. However, clast long axis orientations are consistently sub-horizontal suggesting the slurry transitioned to a laminar flow as the flow velocity decreased in the sill-like intrusion. Millimeter to centimeter scale laminations are ubiquitous throughout the sand body and are locally parallel to the mudstone clast long axes. The laminations are distinct in exposure because alternating layers are preferentially cemented with limonite sourced from later groundwater infiltration. Quantitative microstructural analyses show that the laminations are defined by subtle oscillations in grain alignment between limonite and non-limonite stained layers. Grain packing, size and shape distributions do not vary. The presence of limonite in alternating layers results from differential infiltration of groundwater, indicating permeability changes between the layers despite minimal grain scale differences. Convolute dewatering structures deform the laminations. Dolomite-cemented sand, a signature of hydrocarbon saturation, forms irregular bodies that cross-cut the laminations and dewatering structures. Laminations are not formed in the dolomite-cemented sand. The relative viscosity difference

Decide, design, and dewater de waste: A blueprint from Fitzpatrick

International Nuclear Information System (INIS)

Robert, D.E.

1994-01-01

Using a different process to clean concentrated waste tanks at the James A. FitzPatrick nuclear power plant in New York saved nearly half million dollars. The plan essentially allowed processing concentrator bottoms as waste sludge (solidification versus dewatering) that could still meet burial ground requirements. The process reduced the volume from 802.2 to 55 cubic feet. This resin throwaway system eliminated chemicals in the radwaste systems and was designed to ease pressure on the pradwaste processing system, reduce waste and improve plant chemistry. This article discusses general aspects of the process

Insight into effects of electro-dewatering pretreatment on nitrous oxide emission involved in related functional genes in sewage sludge composting.

Science.gov (United States)

Wang, Ke; Wu, Yiqi; Wang, Zhe; Wang, Wei; Ren, Nanqi

2018-05-26

Electro-dewatering (ED) pretreatment could improve sludge dewatering performance and remove heavy metal, but the effect of ED pretreatment on nitrous oxide (N 2 O) emission and related functional genes in sludge composting process is still unknown, which was firstly investigated in this study. The results revealed that ED pretreatment changed the physicochemical characteristics of sludge and impacted N 2 O related functional genes, resulting in the reduction of cumulative N 2 O emission by 77.04% during 60 days composting. The higher pH and NH 4 + -N, but lower moisture, ORP and NO 2 - -N emerged in the composting of ED sludge compared to mechanical dewatering (MD) sludge. Furthermore, ED pretreatment reduced amoA, hao, narG, nirK and nosZ in ED sludge on Day-10 and Day-60 of composting. It was found that nirK reduction was the major factor impacting N 2 O generation in the initial composting of ED sludge, and the decline of amoA restricted N 2 O production in the curing period. Copyright © 2018 Elsevier Ltd. All rights reserved.

Letramentos acadêmicos e multimodalidade em contexto de EaD semipresencial

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Fabiana Komesu

2012-07-01

Full Text Available De uma perspectiva teórica enunciativo-discursiva, este artigo tem como objetivo discutir o processo de constituição do texto em contexto digital, de maneira particularizada, por meio da problematização de modos e recursos semióticos atualizados na produção acadêmica do universitário que utiliza computador com acesso à internet no processo de Educação a Distância (EaD semipresencial. Interessa investigar como o modelo de letramentos acadêmicos pode ser articulado ao estudo da multimodalidade, considerando-se que em ambiente eletrônico o universitário tem, por hipótese, acesso “ilimitado” a todo e qualquer texto, não apenas ao chamado “verbal”, comumente atribuído ao elemento gráfico. O conjunto do material é formado de textos produzidos por alunos do Curso de Pedagogia semipresencial da Universidade Virtual do Estado de São Paulo (UNIVESP no ano de 2010.Palavras-chave: Escrita. Letramentos. Discurso. Educação a distância. Internet.

Dewatering of sludge using the hydrosoft high-pressure process; Entwaessern von Schlaemmen mit dem Hydrosoft-Hochdruckverfahren

Energy Technology Data Exchange (ETDEWEB)

Eder, C.; Eder, G. [Christian Eder Technology GbR, Neunkirchen (Germany)

1999-07-01

The hydrosoft process permits to dewater sludge, especially also sludge from municipal sewage treatment plant, until it contains a high proportion of dry substance. For existing dewatering systems equipped with the long-lived chamber filter presses, too, the dry matter content of the filter cake can be substantially increased using the hydrosoft process; only the pump system must be retrofitted. As a preliminary measure, tests with mobile pilot plants should be carried out. (orig.) [German] Mit dem Hydrosoft-Verfahren besteht die Moeglichkeit Schlaemme, insbesondere auch Schlaemme aus kommunalen Klaeranlagen, auf hohe Trockensubstanz-Gehalte zu entwaessern. Auch bei bestehenden Entwaesserungsanlagen, die mit den langlebigen Kammerfilterpressen ausgeruestet sind, koennen die Trockensubstanzgehalte der Filterkuchen mit dem Hydrosoft-Verfahren, fuer das dann nur noch das Pumpsystem nachgeruestet werden muss, wesentlich angehoben werden. Vorausgehen sollten jeweils Vorversuche mit mobilen Versuchsanlagen. (orig.)

A case study on stratified settlement and rebound characteristics due to dewatering in Shanghai subway station.

Science.gov (United States)

Wang, Jianxiu; Huang, Tianrong; Sui, Dongchang

2013-01-01

Based on the Yishan Metro Station Project of Shanghai Metro Line number 9, a centrifugal model test was conducted to investigate the behavior of stratified settlement and rebound (SSR) of Shanghai soft clay caused by dewatering in deep subway station pit. The soil model was composed of three layers, and the dewatering process was simulated by self-invention of decompressing devise. The results indicate that SSR occurs when the decompression was carried out, and only negative rebound was found in sandy clay, but both positive and negative rebound occurred in the silty clay, and the absolute value of rebound in sandy clay was larger than in silty clay, and the mechanism of SSR was discussed with mechanical sandwich model, and it was found that the load and cohesive force of different soils was the main source of different responses when decompressed.

Políticas Públicas de Educação no Brasil: A Utilização da EaD Como Instrumento de Inclusão Social

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José Matias Pereira

2010-08-01

Full Text Available The present article searchs to analyze - from the debate on the theory and the concept of education in the distance - the possibilities of intensive use of the EaD, in the context of the new public politics of education, as instrument of social inclusion in Brazil. It is verified, in this analysis that education in the distance, in a context where the continued learning started to be part in the life of the people, is presented as an important tool in the process of construction of public politics of education in the country. We conclude that, in the management of the public politics of education in the distance in Brazil must be advanced in the consistent construction of one arcabouço institucional and in the generation of stimulatons to the research in EaD, with sight to contribute for an increasing social inclusion in the country.

Effects of gamma irradiation on physical-chemical properties and dewatering characteristics of sludges

International Nuclear Information System (INIS)

Groneman, A.F.

1976-01-01

Separation of solids from liquids is a paramount operation in the processes applied in treating sewage and waste waters. Therfore, studies were undertaken to investigate effects of gamma irradiation on the physical-chemical properties of sludges and the de-watering characteristics of anaerobically digested sludge and aerobically activated sludge. A dose of 300 krad reduced the specific resistance of anaerobically digested sludges from 33 x 10 sec 2 /g to approximately 10 x 10 9 sec 2 /g. This conditioning effect was little influenced by the presence of oxygen or nitrogen. Pasteurization increased the specific resistance to filtration up to 48 x 10 9 sec 2 /g. Dewatering characteristics of raw sludge were not affected by irradiation in the presence of oxygen but a slight conditioning effect was noticed when the sludge was irradiated under deaerated conditions. Experimental evidence indicated that gamma irradiation detached organic substances from the sludge flocks resulting in a decrease of the specific resistance and an increase in the Total Organic Carbon (TOC) and the Chemical Oxygen Demand (COD) in the filtrates. Elutriation reduced but did not eliminate the conditioning effect of gamma irradiation. (author)

Possibility of sludge conditioning and dewatering with rice husk biochar modified by ferric chloride.

Science.gov (United States)

Wu, Yan; Zhang, Panyue; Zhang, Haibo; Zeng, Guangming; Liu, Jianbo; Ye, Jie; Fang, Wei; Gou, Xiying

2016-04-01

Rice husk biochar modified by FeCl3 (MRB-Fe) was used to enhance sludge dewaterability in this study. MRB-Fe preparation conditions and dosage were optimized. Mechanisms of MRB-Fe improving sludge dewaterability were investigated. The optimal modification conditions were: FeCl3 concentration, 3mol/L; ultrasound time, 1h. The optimal MRB-Fe dosage was 60% DS. Compared with raw sludge, the sludge specific resistance to filtration (SRF) decreased by 97.9%, the moisture content of sludge cake decreased from 96.7% to 77.9% for 6min dewatering through vacuum filtration under 0.03MPa, the SV30% decreased from 96% to 60%, and the net sludge solids yield (YN) increased by 28 times. Positive charge from iron species on MRB-Fe surface counteracted negative charge of sludge flocs to promote sludge settleability and dewaterability. Meanwhile, MRB-Fe kept a certain skeleton structure in sludge cake, making the moisture pass through easily. Using MRB-Fe, therefore, for sludge conditioning and dewatering is promising. Copyright © 2016. Published by Elsevier Ltd.

A Case Study on Stratified Settlement and Rebound Characteristics due to Dewatering in Shanghai Subway Station

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Jianxiu Wang

2013-01-01

Full Text Available Based on the Yishan Metro Station Project of Shanghai Metro Line number 9, a centrifugal model test was conducted to investigate the behavior of stratified settlement and rebound (SSR of Shanghai soft clay caused by dewatering in deep subway station pit. The soil model was composed of three layers, and the dewatering process was simulated by self-invention of decompressing devise. The results indicate that SSR occurs when the decompression was carried out, and only negative rebound was found in sandy clay, but both positive and negative rebound occurred in the silty clay, and the absolute value of rebound in sandy clay was larger than in silty clay, and the mechanism of SSR was discussed with mechanical sandwich model, and it was found that the load and cohesive force of different soils was the main source of different responses when decompressed.

Combined treatment of solar energy and gamma irradiation to eliminate pathogenic bacteria in dewatered sludge

International Nuclear Information System (INIS)

Hilmy, N.; Harsoyo, S.; Suwirma, S.

1987-01-01

Combined treatment of solar energy and gamma irradiation to eliminate pathogenic bacteria in dewatered sludge. A combined treatment of solar energy and gamma irradiation has been done to eliminate the pathogenic microbes contaminating dewatered sludge. Samples were collected during dry season, i.e. from June to September 1985. To reduce the water content from 70% to 20%, solar energy from sun rays was used, i.e. from 9 a.m. to 2 p.m. for 4 days. Total bacterial count coliform bacteria Escherichia coli, Fecal Streptococcus, Enterobacteriaceae, and Pseudomonas sp were found to be 7.4x10 8 per g, 4.1x10 3 per g, 4.5x10 2 per g, 3.1x10 5 per g, 3.6x10 4 per g, and 5.4x10 3 per g of samples respectively. The combined treatment could reduce the irradiation dose needed to eliminate the pathogenic microbes of samples investigated from 6 to 2 kGy. (author). 5 figs, 11 refs

Bioelectrochemically-assisted anaerobic composting process enhancing compost maturity of dewatered sludge with synchronous electricity generation.

Science.gov (United States)

Yu, Hang; Jiang, Junqiu; Zhao, Qingliang; Wang, Kun; Zhang, Yunshu; Zheng, Zhen; Hao, Xiaodi

2015-10-01

Bioelectrochemically-assisted anaerobic composting process (AnCBE) with dewatered sludge as the anode fuel was constructed to accelerate composting of dewatered sludge, which could increase the quality of the compost and harvest electric energy in comparison with the traditional anaerobic composting (AnC). Results revealed that the AnCBE yielded a voltage of 0.60 ± 0.02 V, and total COD (TCOD) removal reached 19.8 ± 0.2% at the end of 35 d. The maximum power density was 5.6 W/m(3). At the end of composting, organic matter content (OM) reduction rate increased to 19.5 ± 0.2% in AnCBE and to 12.9 ± 0.1% in AnC. The fuzzy comprehensive assessment (FCA) result indicated that the membership degree of class I of AnCBE compost (0.64) was higher than that of AnC compost (0.44). It was demonstrated that electrogenesis in the AnCBE could improve the sludge stabilization degree, accelerate anaerobic composting process and enhance composting maturity with bioelectricity generation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Preconcentration of a low grade uranium ore in CPDU and laboratory investigation to optimize the dewatering conditions of the preconcentration products

International Nuclear Information System (INIS)

Cristovici, M.A.; Berry, T.F.; Raicevic, M.M.; Brady, E.L.; Bredin, E.L.; Leigh, G.W.; Rouleau, J.P.

1982-04-01

A process consisting of pyrite flotation and magnetic concentration of radionuclides was developed by CANMET over several years, to preconcentrate low grade uranium ores prior to leaching. When the economics of the preconcentration-leaching technology was compared with the leaching of the entire ore after pyrite flotation (Base Case variant), the preconcentration method appeared to be economically less advantageous than expected, due to the high cost of dewatering the preconcentration products. Further investigations examined in-depth the metallurgy and dewatering of the two variants: preconcentration and base case. A typical low grade uranium ore from Elliot Lake area was used. The metallurgy was compared based on data from continuous operation (CPDU). In the preconcentration variant the amount of ore directed to leaching was reduced to more than one third of that processed in the base case, while the radionuclide concentration became more than three times higher. However, by preconcentration 7% of the uranium was lost before leaching. Systematic laboratory-scale settling and filter tests optimized the dewatering conditions of the preconcentration technology to the extent that rates similar to those of the base case were obtained

Modelagem do processo de desidratação de lodo anaeróbio em leitos de secagem simulados Anaerobic sludge dewatering process modeling in simulated drying beds

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Sérgio R. A. Soares

2001-05-01

Full Text Available O emprego de leitos de secagem para a desidratação de lodo de descarte de reatores UASB, constitui excelente alternativa, face a sua simplicidade operacional e aos reduzidos custos de implantação. Este trabalho apresenta uma análise dos fenômenos que influenciam o processo de desidratação de lodo anaeróbio, a partir de simulação de leitos de secagem. Neste sentido, são feitas considerações sobre as características e o comportamento do lodo durante cada fase da secagem. Sugere-se também, um modelo matemático para representar o processo de secagem, obtido a partir dos dados experimentais.The employment of drying beds is an excellent option for dewatering of UASB reactor discarded sludge, because of their simple operation and low construction costs. This paper presents an anaerobic sludge dewatering process analysis of the most influential phenomenon based on drying beds simulation. Therefore, some considerations were made about sludge characteristics and behavior during each dewatering stage. A mathematical model for dewatering process representation obtained from experimental data is also suggested.

Application of Fuzzy Synthetic Evaluation in Selection of Best Sludge Dewatering Option in Ghods Town WWTP in Tehran

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Masoud Taheriyoun

2015-03-01

Full Text Available The design and upgrade of sludge treatment systems generally depend on the decision made regarding the appropriate system from among the options available. The selection process has become increasingly important and complex due to recent technological developments that have led to increased diversity in the available options which offer a wide variety of capabilities. The multi-criteria decision making method is one of the techniques recently developed which takes into account all the criteria involved in the decision making process. The Ghods Town WWTP in the west of Tehran located in the vicinity of residential areas has given rise to claims by citizens due to the odors emitted by the sludge sand drying bed, which justifies the replacement of the present sludge dewatering system. For this purpose, the multi-criteria decision making method based on the fuzzy synthetic evaluation method was used to identify the optimal sludge dewatering system appropriate for the WWTP under consideration. Furthermore, weighting of the subjective (social, environmental, and administrative criteria was accomplished using the analytical hierarchy process and the objective (i.e., economic criteria were weighted using the entropy concept. In this method, the triangular fuzzy membership function was also used to take into account the uncertainty associated with each of the decision making parameters. Based on the results obtained, the belt filter press dewatering system and the filter press were identified as the preferred solutions.

A partial hearing animal model for chronic electro-acoustic stimulation

Science.gov (United States)

Irving, S.; Wise, A. K.; Millard, R. E.; Shepherd, R. K.; Fallon, J. B.

2014-08-01

Objective. Cochlear implants (CIs) have provided some auditory function to hundreds of thousands of people around the world. Although traditionally carried out only in profoundly deaf patients, the eligibility criteria for implantation have recently been relaxed to include many partially-deaf patients with useful levels of hearing. These patients receive both electrical stimulation from their implant and acoustic stimulation via their residual hearing (electro-acoustic stimulation; EAS) and perform very well. It is unclear how EAS improves speech perception over electrical stimulation alone, and little evidence exists about the nature of the interactions between electric and acoustic stimuli. Furthermore, clinical results suggest that some patients that undergo cochlear implantation lose some, if not all, of their residual hearing, reducing the advantages of EAS over electrical stimulation alone. A reliable animal model with clinically-relevant partial deafness combined with clinical CIs is important to enable these issues to be studied. This paper outlines such a model that has been successfully used in our laboratory. Approach. This paper outlines a battery of techniques used in our laboratory to generate, validate and examine an animal model of partial deafness and chronic CI use. Main results. Ototoxic deafening produced bilaterally symmetrical hearing thresholds in neonatal and adult animals. Electrical activation of the auditory system was confirmed, and all animals were chronically stimulated via adapted clinical CIs. Acoustic compound action potentials (CAPs) were obtained from partially-hearing cochleae, using the CI amplifier. Immunohistochemical analysis allows the effects of deafness and electrical stimulation on cell survival to be studied. Significance. This animal model has applications in EAS research, including investigating the functional interactions between electric and acoustic stimulation, and the development of techniques to maintain residual

Dewatering e bonifica dell’ area ˝ex Whitehead Motofides˝ (Pisa, Italia

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Nicola Conti

2014-12-01

Full Text Available In 2007 the activities for the remediation of the “ex-Whitehead Motofides area” (in Marina di Pisa, Italy started. In order to allow the contaminated soil excavation in dry conditions a dewatering system was necessary. The water pumped through this system was then treated in an adequate plant. Acque Industriali realized and managed the whole system. The dewatering system was made of suction pins fixed to a depth of 5.5 m, connected by a junction manifold to the suction and booster vacuum assisted pump, which allowed the groundwater release toward the plant. The treatment plant, entirely designed by Acque Industriali and called ITAM (Impianto di Trattamento Acque di Falda Mobile, which means movable groundwater treatment, was realized and set up at the end of 2008. It consisted of a pre-treatment section, made of reinforced concrete, prefabricated nitrogen sweep elements, and a physical chemical treatment plant, in a continuous loop, completely made on skid. The plant, with 25 m3/h of maximum potential, was able to remove possible sedimentable or in suspension material particles from water, iron, manganese, residual organic substances such as hydrocarbons, solvents (chlorinated and not, PCBs, and partly heavy metals. Totally, 98,167 m3 of groundwater were managed in about 25 months of activity. The analytic input and output results confirmed extremely high and satisfactory pollutant removal efficiency. The concentration values of the pollutants, in fact, were always lower than the limits imposed by law.

Hot dewatering and resin encapsulation of intermediate level radioactive waste

International Nuclear Information System (INIS)

Rickman, J.; Birch, D.

1985-01-01

The chemistry of the processes involved in the hot dewatering and encapsulation of alumino-ferric hydroxide floc in epoxide resin have been studied. Pretreatment of the floc to reduce resin attack and hydrolysis and to increase the dimensional stability of the solidified wasteform has been evaluated. It has been demonstrated that removal of ammonium nitrate from the floc and control of the residual water in the resin are important factors in ensuring dimensional stability of the solidified resin. Resin systems have been identified which, together with the appropriate waste pretreatment have successfully encapsulated a simulated magnox sludge producing a stable wasteform having mechanical and physical properties comparable with the basic resin. (author)

An assessment of filter aids and filter cloths in the dewatering of intermediate level wastes

International Nuclear Information System (INIS)

Knibbs, R.H.; Hudson, B.C.; Blackwell, J.C.W.

1984-12-01

This report considers a range of filter cloths and precoat materials intended for use in dewatering intermediate level radioactive wastes, and their interaction when used on a rotary drum vacuum filter. The report outlines the advantages and disadvantages of various grades and types of precoat and shows that grades with permeabilities in the intermediate range, 3 to 4 x 10 -12 m 2 , give satisfactory filtrate quality together with ease of operation. The work on filter cloths shows that: radiation damage is not a limiting factor as regards operational life for any of the cloths examined; polyester-based cloths are unsuitable due to their poor resistance to alkali attack; polyamide cloths are satisfactory; and stainless steel Dutch weave cloths are satisfactory and have the added advantage of high strength. The report also briefly considers the radiation resistance of two elastomeric membranes used on the 'epidermal' filter and shows that the natural latex rubber membrane is considerably more resistant to radiation than the silicone rubber membrane and has an estimated operational life of at least 1200 hours when dewatering Magnox silo sludge or α-contaminated alumino ferric flocs. (author)

Efficient dewatering of bark in heated presses. Survey and pilot-scale trials; Effektivare avvattning av bark i vaermda pressar. Problemkartering samt foersoek i pilotskala

Energy Technology Data Exchange (ETDEWEB)

Haakansson, Martin; Stenstroem, Stig (Lund Inst. of Technology, Lund (SE))

2007-12-15

Dewatering and drying of biofuels such as bark and GROT have received increased importance due to an increased interest to use these products as energy sources. In Sweden there are about 30 bark presses installed, however the amount of available information is very limited about dewatering of bark. The goal with this work is to increase the knowledge about dewatering of bark. Two separate goals have been defined in the project: A. Survey about problems related to dewatering of bark and compilation of operating experiences at Swedish mills. B. Study how different parameters affect bark dewatering at pilot scale experiments. Study different techniques for heating bark and the bark pressing process. The results will mainly be of interest for mills which are handling bark, for municipal power plants who buy wet forest residues (bark, GROT etc.) and for manufacturers of industrial bark pressing equipment. The results show that the dry matter content for birch- and pine bark normally are so high that pressing does not result in dewatering of the barks. Both dry and wet debarking is used and these bark fractions should be pressed separately. On line measurement of the dry matter content for the bark should be used as a standard tool on the bark press. This will facilitate improved control of the bark press during the year. Other conclusions are that smaller bark particles result in an increased dry matter content, large bark- and wood pieces decrease the dewatering in the bark press and that the total residence time in the press nip should be at least 30 seconds. The most common method to take care of bark water is to send it to the evaporators or to the water purification plant. Maintenance of the bark press appears not to be a big problem. Hot pressing can be accomplished in different ways, either the bark press can be heated or the bark can be heated in different ways. The alternatives that have been studied in this project are steaming the bark, heating the bark using

Dewatering treatments to increase dry matter content of the brown seaweed, kelp (Laminaria digitata ((Hudson) JV Lamouroux)).

Science.gov (United States)

Gallagher, Joe A; Turner, Lesley B; Adams, Jessica M M; Dyer, Philip W; Theodorou, Michael K

2017-01-01

Macroalgal water content is an on-going problem for the use of readily accessible seaweeds in sustainable biorefining, including fuel production. Silage is a reduced-water, compactable, easily stored, transportable material. Ensiling could establish a non-seasonal supply of preserved algal biomass, but requires high initial dry matter content to mitigate environmental pollution risks from effluent. This study investigated potential dewatering methods for kelp harvested throughout the year. Treatments included air-drying, osmotic media and acids. Significant interactions between treatment and harvest-time were observed for traits of interest. Fresh weight loss during treatment was composed of changes in water and dry matter content. Air-drying gave reliable increase in final dry matter content; in summer and autumn 30% dry matter content was reached after 24h. Dilute hydrochloric acid reduced stickiness and rendered material suitable for dewatering by screw-pressing; it may be possible to use the consequent pH reduction to promote efficient preservation. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Field experiment and numerical simulation of coupling non-Darcy flow caused by curtain and pumping well in foundation pit dewatering

Science.gov (United States)

Wang, Jianxiu; Liu, Xiaotian; Wu, Yuanbin; Liu, Shaoli; Wu, Lingao; Lou, Rongxiang; Lu, Jiansheng; Yin, Yao

2017-06-01

High-velocity non-Darcy flow produced larger drawdown than Darcy flow under the same pumping rate. When the non-Darcy flow caused by curtain met non-Darcy flow caused by pumping wells, superposition and amplification effect occurred in the coupling area, the non-Darcy flow was defined as coupling non-Darcy flow. The coupling non-Darcy flow can be produced and controlled using different combination of curtain and pumping wells in foundation pit dewatering to obtain the maximum drawdown using the minimum pumping rate. The Qianjiang Century City Station foundation pit of Hangzhou subway, China, was selected as background. Field experiments were performed to observe the coupling non-Darcy flow in round gravel. A generalized conceptual model was established to study the coupling effect under different combination of curtain and pumping wells. Numerical simulations of the coupling non-Darcy flow in foundation pit dewatering were carried out based on the Forchheimer equation. The non-Darcy flow area and flow velocity were influenced by the coupling effect. Short filter tube, large pumping rate, small horizontal distance between filter tube and diaphragm wall, and small vertical distance between the filter tube and confined aquifer roof effectively strengthened the coupling effect and obtained a large drawdown. The pumping wells installed close to a curtain was an intentional choice designed to create coupling non-Darcy flow and obtain the maximize drawdown. It can be used in the dewatering of a long and narrow foundation pit, such as a subway foundation pit.

Bacterial pathogen indicators regrowth and reduced sulphur compounds' emissions during storage of electro-dewatered biosolids.

Science.gov (United States)

Navab-Daneshmand, Tala; Enayet, Samia; Gehr, Ronald; Frigon, Dominic

2014-10-01

Electro-dewatering (ED) increases biosolids dryness from 10-15 to 30-50%, which helps wastewater treatment facilities control disposal costs. Previous work showed that high temperatures due to Joule heating during ED inactivate total coliforms to meet USEPA Class A biosolids requirements. This allows biosolids land application if the requirements are still met after the storage period between production and application. In this study, we examined bacterial regrowth and odour emissions during the storage of ED biosolids. No regrowth of total coliforms was observed in ED biosolids over 7d under aerobic or anaerobic incubations. To mimic on-site contamination during storage or transport, ED samples were seeded with untreated sludge. Total coliform counts decreased to detection limits after 4d in inoculated samples. Olfactometric analysis of ED biosolids odours showed that odour concentrations were lower compared to the untreated and heat-treated control biosolids. Furthermore, under anaerobic conditions, odorous reduced sulphur compounds (methanethiol, dimethyl sulphide and dimethyl disulphide) were produced by untreated and heat-treated biosolids, but were not detected in the headspaces above ED samples. The data demonstrate that ED provides advantages not only as a dewatering technique, but also for producing biosolids with lower microbial counts and odour levels. Copyright © 2014 Elsevier Ltd. All rights reserved.

Gestión de la creatividad en entornos virtuales de aprendizaje colaborativos: un proyecto corporativo de EAD

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Felipe Chibás Ortíz

2014-07-01

Full Text Available Se mantiene abierta en nuestros días la discusión con respecto a las metodologías más efectivas en los entornos virtuales de aprendizaje (EVA colaborativos y su verdadera contribución al desarrollo de la creatividad y la actitud innovadora en los estudiantes, particularmente en los ámbitos corporativos. Las redes sociales educativas basadas en el aprendizaje colaborativo crecen exponencialmente, y se hacen ya incontables en cualquier área del conocimiento. Sin embargo, la estimulación de la creatividad de los usuarios de los EVA en general y en el ámbito corporativo en específico, se ha convertido en un problema científico de gran importancia para las investigaciones en las Ciencias de la Educación. El presente trabajo se propone valorar la presencia de indicadores de creatividad en los estudiantes al interactuar con los entornos virtuales de enseñanza de aprendizaje colaborativo, basados en la experiencia de educación a distancia (EAD corporativa acumulada en Brasil. El método de investigación utilizado es el del estudio de caso, que permitió comparar la realización de un proyecto EAD corporativo a partir de la utilización de las TIC con un enfoque creativo y educomunicativo, con otro que también utilizó las TIC pero con una visión tradicional. Fue realizado en la empresa de consultoría y e-learning Perfectu. Los resultados obtenidos sugieren que el modelo pedagógico adoptado y la forma de utilizar las TIC son las que llevan a resultados innovadores y no las TIC por sí mismas, dado que se observó que el promedio de creatividad del grupo que trabajó bajo el patrón educomunicativo-creativo fue más elevado que para el grupo que trabajó con el paradigma tradicional.

The exploitation of swamp plants for dewatering liquid sewage sludge

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Jiří Šálek

2006-01-01

Full Text Available The operators of little rural wastewater treatment plants have been interested in economic exploitation of sewage sludge in local conditions. The chance is searching simply and natural ways of processing and exploitation stabilized sewage sludge in agriculture. Manure substrate have been obtained by composting waterless sewage sludge including rest plant biomass after closing 6–8 years period of filling liquid sewage sludge to the basin. Main attention was focused on exploitation of swamp plants for dewatering liquid sewage sludge and determination of influence sewage sludge on plants, intensity and course of evapotranspiration and design and setting of drying beds. On the base of determined ability of swamp plants evapotranspiration were edited suggestion solutions of design and operation sludge bed facilities in the conditions of small rural wastewater treatment plant.

Performance of Sandy Dry Beds for sludge dewatering

International Nuclear Information System (INIS)

Al-Muzaini, S.

2003-01-01

Sludge produced by the Jahra treatment plant was assessed. The assessment was directed at determining the performance of sand drying beds. The assessment of quality of the sludge produced was based on the standards for land application of sewage sludge. Analyses were carried out for trace heavy metals and bacteria. The results of analyses showed that the sludge produced was high in organic matter and sand content but low in heavy metals. The collected data indicated that the sand drying beds at the Jahra treatment plant are at present inadequate to handle the projected sludge production. The investigation showed that the sand drying beds are fully used and the plant will require 3-4 times the capacity of the existing drying beds when the plant becomes fully operational. In addition, these sand drying beds are subjected to uncontrollable conditions such as temperature, rainfall and sludge drainage rate. Thus, sand drying beds have become less popular as a dewatering system. This paper evaluates the performance of the existing sand drying beds and suggests the most appropriate technology to alleviate the above mentioned problems. (author)

The use of geotextile tube containers for dewatering the Restigouche open pit zinc mine and settling pond basin in New Brunswick, Canada

Energy Technology Data Exchange (ETDEWEB)

Douheret [Terratube, Saint-Romuald, PQ (Canada)

2010-07-01

This PowerPoint presentation discussed the use of geotextile tube containers for the dewatering of an open pit zinc mine and settling pond in New Brunswick (NB). The zinc and lead mine closed in 1996 and will be re-opened in 2007. Remediation of the site has been challenged by severe discharge criteria for treated water, as well as by the different types of wastewater produced at the site, which is located in a mountainous area with no impermeable soil. The remediation projects include an open pit cleaning procedure where water is removed and the mine is then desludged. A wastewater treatment plant will then be installed. More than 32,000 m{sup 3} of sludge has accumulated at the bottom of the pit. The zinc content of the sludge was estimated at 2.5 ppm. The water management phase of the project will include batch treatments and the addition of 140 metric tonnes of lime to raise the pH and to precipitate metal ions. The sludge management program included the use of mechanical dewatering, the construction of a storage area, and the use of geocontainers for dewatering and temporary containment. Seventeen geotextile containers were used to reduce the zinc content of the water to less than the 250 ppb authorized by environmental agencies. The containers were changed once every 2 months. tabs., figs.

Feasibility study of green wastes composting with digested and dewatering sludge from municipal wastewater treatment plant in Iran

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Neamat Jaafarzadeh Haghighi Fard

2015-09-01

Full Text Available Background: Composting as a waste management technology is becoming more widespread. The purpose of this study was to assess the feasibility and to find the most effective composting process for the ratio of green waste, digested and dewatered sludge from Chonibieh wastewater treatment plant in the west region of Ahvaz. Methods: The composting time was 23 days and the evaluated parameters in this period of the study were organic carbon, total nitrogen, phosphorus, carbon to nitrogen ratio (C/N, moisture content and pH. The C/N ratio was maintained at 30 with weight:weight ratio of 1:1, 1:2, 1:3 (digested and dewatered sludge to green waste. Results: It was observed that vessel R3 produced higher quality of compost with final total nitrogen (1.28%, final total phosphorus (0.71%, final total organic carbon (TOC (25.78% and C/N (20.65% within the 23 days of composting. While vessel R1 produced higher final total nitrogen and total phosphorus with lower amount of total coliform indicating suitable quality of composting. Therefore, the results showed that the characteristics of dewatered sludge mixed with green waste proportion of green waste significantly influenced the compost quality and process dynamics. The results also showed that the quality of final products in all the conditions was in agreement with Global Organic Textile Standard (GOTS and World Health Organization (WHO guidelines. However, the moisture content ratios were lower than the mentioned guidelines. With regards to microbial quality, all three ratios were in agreement with US Environmental Protection Agency (EPA and Iranian guidelines. Conclusion: It is suggested that the final product of composting can be safely used in farmland and green space.

Predicting spread of invasive exotic plants into de-watered reservoirs following dam removal on the Elwha River, Olympic National Park, Washington

Science.gov (United States)

Woodward, Andrea; Torgersen, Christian E.; Chenoweth, Joshua; Beirne, Katherine; Acker, Steve

2011-01-01

The National Park Service is planning to start the restoration of the Elwha River ecosystem in Olympic National Park by removing two high head dams beginning in 2011. The potential for dispersal of exotic plants into dewatered reservoirs following dam removal, which would inhibit restoration of native vegetation, is of great concern. We focused on predicting long-distance dispersal of invasive exotic plants rather than diffusive spread because local sources of invasive species have been surveyed. We included the long-distance dispersal vectors: wind, water, birds, beavers, ungulates, and users of roads and trails. Using information about the current distribution of invasive species from two surveys, various geographic information system techniques and models, and statistical methods, we identified high-priority areas for Park staff to treat prior to dam removal, and areas of the dewatered reservoirs at risk after dam removal.

Experiência de EAD na formação de gestores educacionais: educação visual e construção de narrativas/Experience of on-line education in the educational management training: visual education and construction of narratives

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Carlos Eduardo Albuquerque Miranda

2009-06-01

Full Text Available O objetivo deste artigo é apresentar a experiência de EAD da disciplina ‘Escola, Gestão e Cultura’ no ‘Curso de Especialização em Gestão Educacional’ (CEGE oferecido pela Faculdade de Educação da Unicamp. A proposta de EAD desta disciplina é trabalhar com educação visual e produção de narrativas de professores. Utilizamos as ferramentas de comunicação do ambiente virtual TelEduc para implementar uma dinâmica pedagógica assincrônica de trabalho docente. Esta dinâmica se apresenta como alternativa à lógica de concomitância entre parte presencial e parte em EAD do CEGE. Os resultados apresentados permitem-nos refletir sobre as potencialidades pedagógicas das tecnologias de informação e comunicação e alguns posicionamentos em relação ao trabalho docente em EAD. This article have objective of the present the experience of on-line education of the discipline ‘Escola, Gestão e Cultura’ in the ‘Curso de Especialização em Gestão educacional’ (CEGE offered by the Faculty of Education at Unicamp. The proposed on-line education of this discipline is to work with visual education and production of narratives of teachers. We use the tools of communication in virtual environment TelEduc to implement a pedagogical dynamic asynchronous at teaching work. This dynamic presents itself as an alternative to the logic of concomitance between the presencial part of the CEGE the of the online education part. The results presented allow us to reflect on the pedagogical potential of information and communication technologies and take some positions about to teaching work in the on-line education.

Microstructure and mechanical properties of stress-tailored piezoelectric AlN thin films for electro-acoustic devices

Energy Technology Data Exchange (ETDEWEB)

Reusch, Markus, E-mail: markus.reusch@iaf.fraunhofer.de [Laboratory for Compound Semiconductor Microsystems, IMTEK - Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg (Germany); Fraunhofer Institute for Applied Solid State Physics, Tullastrasse 72, 79108 Freiburg (Germany); Cherneva, Sabina [Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 4, 1113 Sofia (Bulgaria); Lu, Yuan; Žukauskaitė, Agnė; Kirste, Lutz; Holc, Katarzyna [Fraunhofer Institute for Applied Solid State Physics, Tullastrasse 72, 79108 Freiburg (Germany); Datcheva, Maria [Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 4, 1113 Sofia (Bulgaria); Stoychev, Dimitar [Institute of Physical Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 11, 1113 Sofia (Bulgaria); Lebedev, Vadim [Fraunhofer Institute for Applied Solid State Physics, Tullastrasse 72, 79108 Freiburg (Germany); Ambacher, Oliver [Laboratory for Compound Semiconductor Microsystems, IMTEK - Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg (Germany); Fraunhofer Institute for Applied Solid State Physics, Tullastrasse 72, 79108 Freiburg (Germany)

2017-06-15

Highlights: • Sputtered AlN thin films with minimized intrinsic stress gradient. • Gradual increase of N{sub 2} concentration during film growth. • No degradation of AlN film properties by changing process conditions. • 2D Raman mapping of nanoindentation area. - Abstract: Nanoindentation measurements along with atomic force microscopy, X-ray diffraction, and residual stress analyses on the basis of Raman measurements have been performed to characterize stress-tailored AlN thin films grown using reactive RF magnetron sputtering. The intrinsic stress gradient caused by the growing in-plane grain size along film thickness was minimized by increasing the N{sub 2} concentration in the Ar/N{sub 2} gas mixture during the growth process. The increase of N{sub 2} concentration did not degrade the device-relevant material properties such as crystallographic orientation, surface morphology, piezoelectric response, or indentation modulus. Due to comparable crystallographic film properties for all investigated samples it was concluded that mainly the AlN crystallites contribute to the mechanical film properties such as indentation modulus and hardness, while the film stress or grain boundaries had only a minor influence. Therefore, by tailoring the stress gradient in the AlN films, device performance, fabrication yield, and the design flexibility of electro-acoustic devices can be greatly improved.

Escrita acadêmica e desenvolvimento de autoria na formação de professores via EAD: as universidades estão preparadas?

Directory of Open Access Journals (Sweden)

Dorotea Frank Kersch

2017-07-01

Full Text Available A demanda crescente por cursos de formação de professores ocasionou o crescimento dos cursos de licenciatura a distância, os quais se tornaram o tipo de graduação em maior número nessa modalidade de ensino. Dentro deste grupo, o curso de Pedagogia é o que conta com maior número de inscritos. Nosso objetivo é identificar as concepções de trabalho acadêmico que três alunas de Pedagogia em EAD demonstram na elaboração de seus Trabalhos de Conclusão de Curso. Além disso, procura-se verificar como a universidade se prepara para a oferta de seus cursos nessa modalidade: de um lado para desenvolver o letramento acadêmico de seus alunos e, por outro, evitar possíveis plágios. Na grade curricular do curso não há previsão de atividades acadêmicas que preparem os alunos para a escrita do trabalho final. Consequentemente, as alunas, com uma concepção equivocada do que seja um trabalho acadêmico e, para fazer o que a universidade lhes pede, recorrem ao plágio. Antes de criminalizar a atitude das alunas, entretanto, é necessário que as universidades revejam práticas de leitura e escrita, de modo especial na modalidade EAD e se preocupem com a qualidade dos cursos que ofertam.

Environmental control of drilling mud discharge through dewatering in cold weather climates

International Nuclear Information System (INIS)

Wojtanowicz, A.K.

1991-01-01

The paper presents results of an experimental study into the effect of drilling mud temperature upon the dewatering performance. Three temperature ranges were considered: from flowline temperature to room temperature, from room temperature to freezing point, and the freeze (4 degrees F)/thaw (54 degrees F) cycle. The tested drilling fluids included unweighted and weighted fresh water muds and a weighted salt water mud. a sealed laboratory batch reactor was used in the experiments to prevent rapid vaporization of separated water at temperatures above 140 degrees F. Also, ice or ice-salt baths were utilized for deep freezing. The dewaterability (net water removal) was measured with a bench-top plate press under constant expression pressure 30 psi

Detecting Dewatering of Peatland Pastures Using Sentinel-1 Satellite Radar Interferometry.

Science.gov (United States)

Heuff, F.; Samiei-Esfahany, S.; van Leijen, F. J.; Hanssen, R. F.

2017-12-01

The Netherlands are famous for their polders and the draining of soils to be used as pastures. Around 30% of the pastures are situated on peat soils, mostly in the western part of the Netherlands. Peat is composed of organic materials that oxidize and emit greenhouse gases when exposed to air. Oxidation of peat soils results in volume reduction and subsequent subsidence. As a result, the groundwater level rises relative to the surface. Consequently, the soil needs to be dewatered to keep it sufficiently dry for farming, resulting in more oxidation, and therefore more subsidence. This process is bound to continue until the peat soils have disappeared completely. The societal cost of land subsidence due to peat soils are estimated to be 5200 million euro for urban areas and 200 million euro for peatland pastures, for a period until 2050. Measuring the subsidence is not straightforward, if not impossible, with conventional geodetic means as soft soils make it impossible to install fixed benchmarks for repeated surveying. Also, due to the very fast temporal decorrelation over pastures, conventional InSAR approaches cannot measure a signal due to loss of coherence. Here we deploy a complete set of available SAR data from Sentinel-1, Radarsat-2 and TerraSAR-X to estimate the spatio-temporally varying subsidence signal due to the dewatering of peatland pastures over the western part of the Netherlands. We compute the InSAR coherence matrix for all possible interferometric combination, and compute an equivalent single-master stack to estimate the subsidence. Using terrain and land-use defined coherence estimation areas we optimize the phase estimation over areas severely affected by temporal decorrelation. This leads to a first estimate of deformation signals correlated with ancient shallow soil structures due to fluviatile structures. We use the methodology to investigate the effect of advanced local drainage schemes to slow down the subsidence phenomena.

Dewatering of contaminated river sediments

Science.gov (United States)

Church, Ronald H.; Smith, Carl W.; Scheiner, Bernard J.

1994-01-01

Dewatering of slurries has been successfully accomplished by the proper use of polymers in flocculating the fine particulate matter suspended in mineral processing streams. The U.S. Bureau of Mines (USBM) entered into a cooperative research effort with the U.S. Army Corps of Engineers (Corps) for the purpose of testing and demonstrating the applicability of mining flocculation technology to dredging activities associated with the removal of sediments from navigable waterways. The Corps has the responsibility for maintaining the navigable waterways in the United States. Current technology relies primarily on dredging operations which excavate the material from the bottom of waterways. The Corps is testing new dredging technology which may reduce resuspension of sediments by the dredging operation. Pilot plant dredging equipment was tested by the Corps which generated larger quantities of water when compared to conventional equipment, such as the clam shell. The transportation of this 'excess' water adds to the cost of sediment removal. The process developed by the USBM consists of feed material from the barge being pumped through a 4-in line by a centrifugal pump and exiting through a 4-in PVC delivery system. A 1,000-gal fiberglass tank was used to mix the polymer concentrate. The polymer was pumped through a 1-in line using a variable speed progressive cavity pump and introduced to the 4-in feed line prior to passing through a 6-in by 2-ft static mixer. The polymer/feed slurry travels to the clarifying tank where the flocculated material settled to the bottom and allowed 'clean' water to exit the overflow. A pilot scale flocculation unit was operated on-site at the Corps' 'Confined Disposal Facility' in Buffalo, NY.

Development of producing equipment of mixed butane-air with low dew point. Energy saving dewatering apparatus and 6A-Gas producing apparatus utilizing vaporization latent heat of butane and potential heat of air

Energy Technology Data Exchange (ETDEWEB)

Komine, Jin; Okada, Hiroto; Taniue, Nobuo; Tanoue, Keiju; Yamada, Tatsuhiko; Maekawa, Hisami; Murakami, Keiji

1988-02-10

A producing equipment of mixed butane-air with low dew point was developed. The dewatering was made during the period from the middle of May to the middle of October with high atmospheric humidity. The production capacity of the mixed gas is 3000 Nm/sup 3/ of 22% of butane and 78% of air per hour. The designed dew point is 18/sup 0/C or less under the pressure of 0.7 kg/cm/sup 2/G. The saturation temperature is 7.5/sup 0/C after the liquid butane is evacuated by a regulating valve. The air introduced into the dehumidifier through finned tubes is cooled to dewater based on those data. The partially vaporized butane is completely gasified by hot water in a vaporizer and mixed with the dewatered air by a venture mixer to produce the mixed butane-air. When the dewatering is incomplete, the spray nozzle must be just exchanged. The dew point of the produced gas was sufficiently below the designed value. The investment cost is low. The total operating cost is reduced by the remarkably decreased fuel cost though the power cost is increased. The noise level is low and the heat control is easy. (11 figs, 4 tabs, 1 photo)

Vibrating membrane filtration as improved technology for microalgae dewatering.

Science.gov (United States)

Nurra, Claudia; Clavero, Ester; Salvadó, Joan; Torras, Carles

2014-04-01

The effect of shear-enhanced filtration by vibratory process in microalgae dewatering is presented in this paper. The aim of this research was to investigate the technical performance and improvement of vibrating membrane filtration compared with conventional tangential cross-flow filtration in microalgae concentration. An industrial-scale available commercial set-up was used. Several membrane materials as polyethersulfone, polyacrylonitrile, etc., and mean pore sizes (from 7000Da to 0.2μm) were tested and compared in both filtration set-ups. Experiments were carried-out with Nannochloropsis gaditana and Phaeodactylum tricornutum microalgae. It has been demonstrated that, even if the choice of the membrane depends on its cut-off, its material and the type of microalgae filtrated, dynamic filtration is always the best technology over a conventional one. If with conventional filtration permeability values were in the vicinity of 10L/h/m(2)/bar in steady state phase, with dynamic filtration these values increased to 30L/h/m(2)/bar or more. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cross-Modal Perception of Noise-in-Music: Audiences Generate Spiky Shapes in Response to Auditory Roughness in a Novel Electroacoustic Concert Setting.

Science.gov (United States)

Liew, Kongmeng; Lindborg, PerMagnus; Rodrigues, Ruth; Styles, Suzy J

2018-01-01

Noise has become integral to electroacoustic music aesthetics. In this paper, we define noise as sound that is high in auditory roughness, and examine its effect on cross-modal mapping between sound and visual shape in participants. In order to preserve the ecological validity of contemporary music aesthetics, we developed Rama , a novel interface, for presenting experimentally controlled blocks of electronically generated sounds that varied systematically in roughness, and actively collected data from audience interaction. These sounds were then embedded as musical drones within the overall sound design of a multimedia performance with live musicians, Audience members listened to these sounds, and collectively voted to create the shape of a visual graphic, presented as part of the audio-visual performance. The results of the concert setting were replicated in a controlled laboratory environment to corroborate the findings. Results show a consistent effect of auditory roughness on shape design, with rougher sounds corresponding to spikier shapes. We discuss the implications, as well as evaluate the audience interface.

Consolidation theory and its applicability to the dewatering and covering of uranium-mill tailings

International Nuclear Information System (INIS)

Gates, T.E.

1982-11-01

This report is a review and evaluation of soil consolidation theories applicable for evaluating settlement during dewatering and subsequent covering of uranium-mill tailings. Such theories may be used to predict both consolidation and water flow related effects in uranium-mill tailings during drainage, following sluicing into burial pits. A consolidation theory to be useful must consider the effect of time-dependent loads, nonhomogeneous soil mass, nonlinear variation of soil properties with the stress-state parameters, large strain, and saturated and unsaturated flow. Constitutive relations linking the stress-deformation-state variables with void ratio should be adopted for predicting both consolidation and fluid-flow interaction in unsaturated uranium-mill tailings

Upgrading of brown coal by slurry-dewatering; Kattan no yuchu dassui ni yoru clean kotai nenryo no seizo

Energy Technology Data Exchange (ETDEWEB)

Okuma, O.; Shimizu, T.; Inoue, T.; Shigehisa, T.; Deguchi, T.; Katsushima, S. [Kobe Steel, Ltd., Kobe (Japan)

1996-10-28

This paper describes an outline of solid fuel production process from brown coal and the investigation results of its elemental techniques. Dried coal is produced by this process which consists of a dewatering of crushed brown coal in oil-based solvent, a solid and liquid separation of slurry, and a remained oil recovery by heating. This process is characterized by the higher thermal efficiency compared with usual drying and the restraint of spontaneous combustion of product coal. It was revealed that solid fuel with low moisture, low ash, low sulfur, and suppressed spontaneous combustion property can be produced from Australian brown coal through this process. From the comparison between kerosene and fuel oil A, it was confirmed that the oil content during dewatering was smaller and the oil recovery by heating was easier by using a solvent with lower boiling point. It was also confirmed that the spontaneous combustion property can be suppressed using small amount of asphalt by solving asphalt in the solvent and adsorbing asphalt on the surface of brown coal. From these results, low rank coals including brown coal, which are difficult to use, are expected to be used as clean coal with low ash and low sulfur through this process. 2 refs., 7 figs., 2 tabs.

Hydrothermal and alkaline hydrothermal pretreatments plus anaerobic digestion of sewage sludge for dewatering and biogas production: Bench-scale research and pilot-scale verification.

Science.gov (United States)

Li, Chunxing; Wang, Xingdong; Zhang, Guangyi; Yu, Guangwei; Lin, Jingjiang; Wang, Yin

2017-06-15

To test the feasibility and practicability of the process combing hydrothermal pretreatment for dewatering with biogas production for full utilization of sewage sludge, hydrothermal/alkaline hydrothermal pretreatments and in turn anaerobic digestion of the filtrates obtained after dewatering the pretreated sludge were performed at bench- and pilot-scales. The hydrothermal temperature fell within the range of 140 °C-220 °C and the pretreatment time varied from 30 min to 120 min. For the alkaline hydrothermal pretreatment the pH value of the sludge was adjusted to 9.0-11.0 by adding Ca(OH) 2 . The results showed that the dewaterability of the sewage sludge was improved with increasing pretreatment temperature but the impact of the pretreatment time was not significant. The addition of Ca(OH) 2 gave better performance on the subsequent mechanical dewatering of the pretreated sludge compared to pure hydrothermal pretreatment, and the higher the pH value was, the better the dewaterability of the pretreated sludge was. The conditions of 180 °C/30 min and 160 °C/60 min/pH = 10.0 (for hydrothermal and alkaline hydrothermal pretreatments, respectively) resulted in relatively good results in the theoretical energy balance, which were verified in the pilot-scale tests. Based on the data from the pilot tests, the alkaline hydrothermal process realized self-sufficiency in energy at the cost of a proper amount of CaO. Copyright © 2017 Elsevier Ltd. All rights reserved.

BIBLIOTEC: experiência do Curso de Extensão em EAD mediado por computador

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Eliane L. da Silva Moro

2003-06-01

Full Text Available Este artigo apresenta relato de experiência do Curso BIBLIOTEC em Educação Aberta a Distância (EAD mediado por computador. O Curso teve como foco a biblioteca escolar, que exerce um papel fundamental na formação do cidadão crítico, consciente e solidário. O BIBLIOTEC desenvolveu-se através de eixos temáticos, realizando discussões e reflexões com atividades síncronas (chat e atividades assíncronas (EquiText, fórum, e-mails entre outros, na forma de Extensão, com a carga horária de 80 horas. Profissionais que atuam em bibliotecas escolares dos mais diferentes locais do Brasil e acadêmicos do Curso de Biblioteconomia e Pedagogia compartilharam um novo ambiente de aprendizado, apoiado na tecnologia da informação e da comunicação. O Curso foi ministrado pelos professores do Núcleo ECHOS/FABICO/ UFRGS. Foram utilizadas várias ferramentas auxiliando na construção colaborativa de projetos, discussões, fóruns promovendo a interação entre os participantes, proporcionando a geração de novos projetos e educação continuada.

Identification (GC and GC-MS) of unsaturated acetates in Elasmopalpus lignosellus and their biological activity (GC-EAD and EAG).

Science.gov (United States)

Jham, Gulab N; da Silva, Alexsandro A; Lima, Eraldo R; Viana, Paulo

2005-02-01

Two insect colonies of Elasmopalpus lignosellus were reared in our laboratory, the first being initiated from pupae obtained from a cornfield in the region of Sete Lagoas, Minas Gerais and the second from a cornfield in the region of Goiânia, Goiás. From the two colonies, two extracts were prepared from the pheromone glands of virgin E. lignosellus females. The extract obtained from the first colony was designated as extract 1 while the extract obtained from the second colony was designated as extract 2. Extract 1 was analyzed by gas chromatography-mass spectrometry (GC-MS) with (Z)-9-hexadecenyl acetate [(Z)-9-HDA] and (Z)-11-hexadecenyl acetate [(Z)-11-HDA] being identified and confirmed by the formation of DMDS derivatives. In addition, a third acetate, which could be either (E)-8-hexadecenyl acetate [(E)-8-HDA] or (E)-9-hexadecenyl acetate [(E)-9-HDA] was detected by GC-MS. Extract 2 was analyzed by gas chromatography (GC) and gas chromatography-electroannetography (GC-EAD) revealing the presence of (Z)-11-HDA and (Z)-9-TDA. In addition, the same compounds elicited a response with the E. lignosellus male antenna obtained from the second insect colony. Electroantennography (EAG) screening with the male E. lignosellus antenna (obtained from the second insect colony) was conducted with the 23 possible tetradecenyl acetates (TDA) and 22 hexadecenyl acetates (HDA) as standards. Out of the 23 TDA isomers evaluated, only (Z)-9-TDA elicited a response and out of the 22 HDA [(Z) and (E) isomers gamma2 to delta13] evaluated only (Z)-11-HDA elicited a response. The acetate compositions of two extracts obtained from insects originating from the two states (Minas Gerais and Goiás) of Brazil were different from one another as well as from that obtained from insects in Tifton, GA, USA. The bioactivity data (GC-EAD) of the extract 2 differed from those reported for the Tifton, GA, USA population. These data suggest polymorphism in relation to the insect populations found in

Assessment of technical-scale dewatering results in decanters on the basis of measurements of water types in sewage sludge; Bestimmung grosstechnischer Entwaesserungsergebnisse in Dekantern basierend auf der Messung der Wasserarten von Klaerschlaemmen

Energy Technology Data Exchange (ETDEWEB)

Kopp, J.; Dichtl, N. [Technische Univ. Braunschweig (Germany). Inst. fuer Siedlungswasserwirtschaft

1999-07-01

In a sewage sludge suspension, three water portions can be measured and distinguished from each other. The free water portion is not bound to sludge particles and can be separated by mechanical dewatering. The interstitial water portion bound by capillary forces and bound water (on surfaces and in cells) remain in the sludge cake after dewatering. The described measuring system for thermo-gravimetric determination of the water portions of sewage sludge was adjusted and calibrated at Braunschweig Technical University and permits prognosticating the maximum attainable content of solids through mechanical dewatering in high-performance decanters. (orig.) [German] In einer Klaerschlammsuspension koennen drei Wasseranteile messtechnisch unterschieden werden. Der freie Wasseranteil ist nicht an die Schlammpartikel gebunden und ist bei einer maschinellen Entwaesserung abtrennbar. Der kapillar gehaltene Zwischenraumwasseranteil und das gebundene Wasser (auf Oberflaechen und in Zellen) verbleibt nach der Entwaesserung im Schlammkuchen. Die an der TU Braunschweig angepasste und kalibrierte Messanlage zur thermo-gravimetrischen Bestimmung der Wasseranteile eines Klaerschlammes ermoeglicht es, den maximal bei der maschinellen Entwaesserung in Hochleistungsdekantern erreichbaren Feststoffgehalt zu prognostizieren. (orig.)

Influência da estrutura organizacional-administrativa das instituições de ensino superior no desenvolvimento de competências docentes para atuação na EAD

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Fernanda Roda de Souza Araújo Cassundé

2016-05-01

Full Text Available A performance dos indivíduos que atuam na educação a distância é influenciada por diversos fatores, porém a dimensão organizacional-administrativa da instituição de ensino se constitui um elemento fundamental para o desenvolvimento das competências eletrônicas docentes, haja vista que tanto deve reforçar as habilidades quanto promover a conquista de novas aptidões que lhes permitam conhecer e julgar por que, quando e como utilizar as TICs na EAD. Partindo dessa premissa, esse estudo procura responder a seguinte pergunta: Como o desenvolvimento das competências eletrônicas dos professores do ensino superior se relacionam com a dimensão organizacional-administrativa das instituições de ensino superior? Para tanto, foi realizado um qualitativo interpretativo básico. Foi escolhido como lócus a Universidade Federal do Vale do São Francisco e, como unidade de análise, o curso de especialização em Gestão Pública vinculado ao Programa Nacional de Administração Pública (PNAP. A coleta de dados foi realizada mediante pesquisa documental e entrevistas com roteiro semiestruturado. Os resultados da pesquisa mostram claramente que vários fatores dessa dimensão são importantes para o desenvolvimento das competências eletrônicas docentes e que questões políticas institucionais precisam ser superadas e a periodicidade do treinamento precisa existir para que a EAD possa se firmar na instituição.

Cross-Modal Perception of Noise-in-Music: Audiences Generate Spiky Shapes in Response to Auditory Roughness in a Novel Electroacoustic Concert Setting

Directory of Open Access Journals (Sweden)

Kongmeng Liew

2018-02-01

Full Text Available Noise has become integral to electroacoustic music aesthetics. In this paper, we define noise as sound that is high in auditory roughness, and examine its effect on cross-modal mapping between sound and visual shape in participants. In order to preserve the ecological validity of contemporary music aesthetics, we developed Rama, a novel interface, for presenting experimentally controlled blocks of electronically generated sounds that varied systematically in roughness, and actively collected data from audience interaction. These sounds were then embedded as musical drones within the overall sound design of a multimedia performance with live musicians, Audience members listened to these sounds, and collectively voted to create the shape of a visual graphic, presented as part of the audio–visual performance. The results of the concert setting were replicated in a controlled laboratory environment to corroborate the findings. Results show a consistent effect of auditory roughness on shape design, with rougher sounds corresponding to spikier shapes. We discuss the implications, as well as evaluate the audience interface.

Revista Multitexto do CEAD/Unimontes: um periódico científico na produção de qualidade de gestão em EAD

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Maria Ângela Lopes Dumont Macedo

2015-06-01

Full Text Available As atuais tendências de gestão em educação fazem usufruto de inúmeras ferramentas de ação e inovação para a consecução de suas metas e resultados. Todavia, é preciso que as metas sejam investidas de rigor e vigor para fundamentar ações, gerar pertinência, garantir relevância e alcançar eficácia. A pesquisa científica surge como uma proposta singular para a aplicação de qualidade em processos de gestão nas várias instâncias. Como marco de sua gestão, o Centro de Educação a Distância da Universidade Estadual de Montes Claros – CEAD/Unimontes instituiu a Revista Multitexto do CEAD/Unimontes. Um periódico científico que condense produções científicas em EAD e áreas correlatas. O objetivo desse trabalho foi relatar a experiência de implantação da Revista Multitexto no CEAD/Unimontes. Através de um relato de experiência, destacou-se a trajetória de implantação, comunicando a preocupação da instituição e movimentos de sua gestão. Por certo que um periódico científico investe, através da ciência, valores de relevância e fundamentação, e nesse ínterim, competem diretamente para a consecução e objetivos e aplicação de qualidade em processos de gestão, como a em EAD.

Use of a water treatment sludge in a sewage sludge dewatering process

Science.gov (United States)

Górka, Justyna; Cimochowicz-Rybicka, Małgorzata; Kryłów, Małgorzata

2018-02-01

The objective of the research study was to determine whether a sewage sludge conditioning had any impact on sludge dewaterability. As a conditioning agent a water treatment sludge was used, which was mixed with a sewage sludge before a digestion process. The capillary suction time (CST) and the specific filtration resistance (SRF) were the measures used to determine the effects of a water sludge addition on a dewatering process. Based on the CST curves the water sludge dose of 0.3 g total volatile solids (TVS) per 1.0 g TVS of a sewage sludge was selected. Once the water treatment sludge dose was accepted, disintegration of the water treatment sludge was performed and its dewaterability was determined. The studies have shown that sludge dewaterability was much better after its conditioning with a water sludge as well as after disintegration and conditioning, if comparing to sludge with no conditioning. Nevertheless, these findings are of preliminary nature and future studies will be needed to investigate this topic.

STABILIZATION OF DEWATERED SEWAGE SLUDGE BY AEROBIC COMPOSTING METHOD: USING SAWDUST AS BULKING AGENTS

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A PARVARESH

2002-12-01

Full Text Available Introduction. Sludge production from municipal wastewater treatment plants should have quality standards before disposal in to the environment. Environmental specialists classified sewage sludge as a hazardous waste because of high organic compounds and pathogenic microorganisms. They belive that sewage should be stabilized before disposal and so composting of sewage sludge is an effective and economical method to stabilize. Sewage sludge compost could be used to improve soil structure and enrich the soil with nutrients. Methods. To evaluate the optimum conditions of aerobic compost, the mixture of dewatered sewage sludge from Isfahan municipal waste water treatment plant and sawdust as bulking agent were used. Pilot scale study were performed in Isfahan municipal waste water treatment plant. To perform this research project, the dewatered sewage sludge with humidity between 78 to 82 percent were mixed with sawdust. Turning over method of the piles with one week interval were applied to aerate the mixture. Temperature of the piles were monitored at different depths daily. Other parameters such as N, G, organic matters and pH were determined weekly. Total and fecal coli form, and salmonella were determined at the beginning and end of the composting process, also heavy metals were measured at the same time. Results. The results of this study showed that after days, temperature of the mixture reached up to 55 G, and were stabled for 15 days. Humidity, organic matter, organic carbon and GIN ratio of the mixture decreased over the period of the study, due to increasing the temperature. Also organic matter and humidity mainly decreased in thermofilic phase. The number of total and fecal coliform and also salmonella decreased to A class standards of US.EPA at the end of the operation. Discussion. The results of the study also showed that, this type of composting method is reliable, and simple to schedule, with high flexibility and low odor

Evaluate, Analyze, Describe (EAD: Confronting Underlying Issues of Racism and Other Prejudices for Effective Intercultural Communication

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Daniel Velasco

2015-09-01

Full Text Available Racism and other prejudices have hindered efforts to diversify and further many fields, including education, psychology, politics, law, and healthcare (Race for Opportunity, 2010. Although there are many ways to combat these prejudices, intercultural communication continues to be a vital component in assisting individuals and groups with valuing the past, understanding the present, and preparing for the future of communication in a global society (Sadri and Flammia, 2011, p. 19. This paper provides a brief overview of pertinent research and major theories related to communicating with people of different cultural backgrounds, as well as useful techniques and strategies to use when teaching in international or multinational classrooms, and working or consulting in international or multinational companies, organizations, and educational institutions. It also includes data collected via surveys and interviews that helps to shed light on underlying issues of racism and discontent in Japanese and Nigerian populations within Japan, and concludes with a description of a new approach to one of the most common intercultural communication exercises called the E.A.D. (Evaluate, Analyze, Describe. While this exercise has proved to increase cultural awareness and open the lines of communication between individuals from various cultural and lingual backgrounds, research also shows that other strategies may be necessary to achieve desired levels of communication.

The Hugh Davies Collection: live electronic music and self-built electro-acoustic musical instruments, 1967–1975

Directory of Open Access Journals (Sweden)

Dr James Mooney

2017-04-01

Full Text Available The Hugh Davies Collection (HDC at the Science Museum in London comprises 42 items of electronic sound apparatus owned by English experimental musician Hugh Davies (1943–2005, including self-built electro-acoustic musical instruments and modified sound production and manipulation hardware. An early proponent of ‘live electronic music’ (performed live on stage rather than constructed on magnetic tape in a studio, Davies’s DIY approach shaped the development of experimental and improvised musics from the late 1960s onwards. However, his practice has not been widely reported in the literature, hence little information is readily available about the material artefacts that constituted and enabled it. This article provides the first account of the development of Davies’s practice in relation to the objects in the HDC: from the modified electronic sound apparatus used in his early live electronic compositions (among the first of their kind by a British composer; through the ‘instrumental turn’ represented by his first self-built instrument, Shozyg I (1968; to his mature practice, where self-built instruments like Springboard Mk. XI (1974 replaced electronic transformation as the primary means by which Davies explored new and novel sound-worlds. As well as advancing knowledge of Davies’s pioneering work in live electronics and instrument-building and enhancing understanding of the objects in the HDC, this article shows how object biographic and archival methodologies can be combined to provide insight into the ways in which objects (instruments, technologies and practices shape each other over time.

Process Design and Economics for the Production of Algal Biomass: Algal Biomass Production in Open Pond Systems and Processing Through Dewatering for Downstream Conversion

Energy Technology Data Exchange (ETDEWEB)

Davis, Ryan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Markham, Jennifer [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kinchin, Christopher [National Renewable Energy Lab. (NREL), Golden, CO (United States); Grundl, Nicholas [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tan, Eric C.D. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Humbird, David [DWH Process Consulting, Denver, CO (United States)

2016-02-17

This report describes in detail a set of aspirational design and process targets to better understand the realistic economic potential for the production of algal biomass for subsequent conversion to biofuels and/or coproducts, based on the use of open pond cultivation systems and a series of dewatering operations to concentrate the biomass up to 20 wt% solids (ash-free dry weight basis).

Analysis of sound absorption performance of an electroacoustic absorber using a vented enclosure

Science.gov (United States)

Cho, Youngeun; Wang, Semyung; Hyun, Jaeyub; Oh, Seungjae; Goo, Seongyeol

2018-03-01

The sound absorption performance of an electroacoustic absorber (EA) is primarily influenced by the dynamic characteristics of the loudspeaker that acts as the actuator of the EA system. Therefore, the sound absorption performance of the EA is maximum at the resonance frequency of the loudspeaker and tends to degrade in the low-frequency and high-frequency bands based on this resonance frequency. In this study, to adjust the sound absorption performance of the EA system in the low-frequency band of approximately 20-80 Hz, an EA system using a vented enclosure that has previously been used to enhance the radiating sound pressure of a loudspeaker in the low-frequency band, is proposed. To verify the usefulness of the proposed system, two acoustic environments are considered. In the first acoustic environment, the vent of the vented enclosure is connected to an external sound field that is distinct from the sound field coupled to the EA. In this case, the acoustic effect of the vented enclosure on the performance of the EA is analyzed through an analytical approach using dynamic equations and an impedance-based equivalent circuit. Then, it is verified through numerical and experimental approaches. Next, in the second acoustic environment, the vent is connected to the same external sound field as the EA. In this case, the effect of the vented enclosure on the EA is investigated through an analytical approach and finally verified through a numerical approach. As a result, it is confirmed that the characteristics of the sound absorption performances of the proposed EA system using the vented enclosure in the two acoustic environments considered in this study are different from each other in the low-frequency band of approximately 20-80 Hz. Furthermore, several case studies on the change tendency of the performance of the EA using the vented enclosure according to the critical design factors or vent number for the vented enclosure are also investigated. In the future

A avaliação vista sob o aspecto da educação a distância La evaluación bajo el aspecto de la educación a distancia Evaluation from an EAD perspective

Directory of Open Access Journals (Sweden)

Maurício Rosa

2006-03-01

Full Text Available Este artigo trata da avaliação como um aspecto bastante relevante para a educação em geral, que também deve ser pensado e discutido frente à Educação a Distância (EAD. Assim, a partir de nossa experiência como professores e tendo por contexto um curso realizado totalmente à distância, analisamos algumas interações ocorridas ao longo do curso, que foi desenvolvido tendo como norte a teoria educacional construcionista. Valemo-nos também desta teoria para elaborar nossas idéias a respeito do caráter da avaliação frente a uma concepção formativa, em um ambiente de EAD, o qual valorizou todos os tipos de interação. Então, aliamos o Construcionismo1 à Avaliação Formativa que visa ao aperfeiçoamento do processo de aprendizagem do aluno em vez de buscar medir o que este aprendeu.Este artículo trata de la evaluación como un aspecto muy destacado en la educación, y que debe ser discutido en el marco de la Educación a Distancia (EaD. Luego, con base en nuestra experiencia como docentes y en el marco de un curso realizado totalmente a distancia, investigamos algunas interacciones ocurridas a lo largo del curso que se desarrolló teniendo en cuenta la teoría educacional Construccionista. Empleamos también esta teoría al elaborar nuestras ideas respecto al carácter de la evaluación frente a una concepción formativa, en un ambiente de EaD, en el que se valoro a todo tipo de interacciones. De hecho, unimos el Construccionismo a la Evaluación Formativa buscando el mejor desarrollo del proceso de aprendizaje en lugar de buscar una medida de aquello que un alumno pueda haber aprendido.This paper presents the assessment as an aspect, sufficiently important for the education in general, that also it must be thought and be discuss in front of the Distance Education. Thus, from our experience as professors and having for context a course fulfilled totally at distance, we analyzed some interactions that occurred during the course

Reuse of liquid, dewatered, and composted sewage sludge on agricultural land: effects of long-term application on soil and crop.

Science.gov (United States)

Mantovi, Paolo; Baldoni, Guido; Toderi, Giovanni

2005-01-01

To evaluate the effects of repeated sewage sludge applications in comparison to mineral fertilisers on a winter wheat-maize-sugar beet rotation, a field experiment on a silty-loam soil, in the eastern Po Valley (Italy), was carried out since 1988. Municipal-industrial wastewater sludge as anaerobically digested, belt filtered (dewatered), and composted with wheat straw, has been applied at 5 and 10 Mg DM ha(-1)yr(-1). Biosolids gave crop yields similar to the highest mineral fertiliser dressing. However, with the higher rate of liquid and dewatered sludge, excessive N supply was harmful, leading to wheat lodging and poor quality of sugar beet and wheat crops. From this standpoint compost use was safer. Biosolids increased organic matter (OM), total N, and available P in the soil and reduced soil alkalinity, with more evident effects at the highest rate. Compost caused the most pronounced OM top soil accumulation. Significant accumulations of total Zn and Cu were detected in amended top soil, but no other heavy metals (Cd, Cr, Ni, Pb), whose total concentration remained well below the hazard limits. Biosolid applications significantly increased the content of N, P, Zn, and Cu in wheat grain, N and Cu in sugar beet roots, and only Cu in maize grain. The application of biosolids brought about notable benefits to soil fertility but it was associated with possible negative effects on water quality due to increased P availability and on soil ecology due to Zn accumulation.

Universidades que ofertam cursos EaD no estado de Santa Catarina: uma comparaçâo entre o nível de maturidade e o índice potencial de maturidade

Directory of Open Access Journals (Sweden)

Cleide Tirana Nunes Possamai

2017-12-01

Full Text Available Em virtude de sua constante evolução, a Educação a Distância tornou-se um tema de intensas pesquisas, afinal o objetivo desta modalidade de ensino é facilitar o acesso à população a aperfeiçoamento constate, principalmente pela utilização frequente de novas tecnologias e sua modernização, consolidando-se desta forma como uma opção que a população encontra para se atualizar. Este estudo tem por objetivo comparar o nível de maturidade e o índice potencial de maturidade nas instituições de ensino que ofertam cursos em EAD no Estado de Santa Catarina. Para atingir este objetivo utilizou-se um modelo de maturidade adaptado para as características deste segmento. Por meio de uma pesquisa quantitativa, descrita, de corte transversal e método survey, os dados deste estudo foram obtidos. O tratamento destes dados concretizou-se por meio da moda. A tabulação foi efetuada para identificar o NM e o IPM de cada IES buscando realizar a devida comparação. Os achados da pesquisa apresentam o nível de maturidade e o índice potencial de maturidade de cada IES, bem como a comparação entre ambos para verificar se existe um nível de maturidade que seja ideal para as Universidades de Santa Catarina que ofertam cursos em EAD.

Dewatering and RCRA partial closure action on solar evaporation ponds, Rocky Flats Plant, Golden, Colorado

International Nuclear Information System (INIS)

1991-06-01

The Department of Energy (DOE) has prepared an Environmental Assessment (DOE/EA-0487) on its proposal to partially close five solar evaporation ponds at the Rocky Flats Plant (RFP) pursuant to the requirements of the Resource Conservation and Recovery Act (RCRA). This proposal would be known as a RCRA partial closure and would be accomplished by dewatering the ponds, where necessary, and converting any remaining sludge or evaporator concentrate to a solid wasteform (pondcrete and saltcrete). The pond sites would be stabilized to prevent erosion or other disturbance to the soil and to prevent infiltration of rain or snowmelt. The solid wasteform would be transported offsite for disposal. The five solar ponds (designated 207-A, 207-B (north, center, and south), and 207-C), are the only solar evaporation ponds that exist at the RFP. A finding of no significant impact is included

The influence of zeta potential and yield stress on the filtration characteristics of a magnesium hydroxide simulant

International Nuclear Information System (INIS)

Biggs, Simon; Nabi, Rafiq; Poole, Colin; Patel, Ashok

2007-01-01

In the UK, irradiated fuels from Magnox reactors are often stored in water-filled ponds under alkaline conditions, so as to minimise corrosion of fuel cladding. This is important to prevent or reduce leakage of soluble fission products and actinides to the pond water. A variety of intermediate level wastes derived from Magnox materials are stored at power stations. Under these alkaline conditions, various species of magnesium are formed, of which magnesium hydroxide is the dominant material. The particle-fluid interactions are significant for the design and operation of facilities for hydraulic retrieval, filtration, dewatering and ion exchange treatment of fuel storage pond water and stored wet Magnox wastes. Here we describe a study of particulate properties and filtration characteristics of oxide particle simulants under laboratory conditions. Cake and medium resistance data were correlated across a range of pH conditions with electro-acoustic zeta potential and shear yield stress measurements, as a function of particle volume fractions. The influence of zeta potential on filtration properties arises directly from the interaction of particles within the sediment cake. (authors)

Metodologia de ensino via educação a distância (EaD) integradora e colaborativa para o ensino superior, baseada na percepção dos alunos (MAPICes)

OpenAIRE

Vitorino, Elizete Vieira

2004-01-01

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção. O ensino superior é o instrumento principal de transmissão da experiência cultural e científica acumulada pela humanidade. São as universidades que reúnem um conjunto de funções tradicionais associadas ao progresso e a transmissão do saber: pesquisa e inovação, ensino e formação, educação a distância (EaD). Justifica-se, então, que se desenvolvam trabalhos vol...

Investigation of Parameters Affecting Gypsum Dewatering Properties in a Wet Flue Gas Desulphurization Pilot Plant

DEFF Research Database (Denmark)

Hansen, Brian Brun; Kiil, Søren

2012-01-01

of impurities (0.002 M Al2F6; 50 g quartz/L; 0.02 M Al3+, and 0.040 M Mg2+) were investigated. In addition, slurry from a full-scale wet FGD plant, experiencing formation of flat shaped crystals and poor gypsum dewatering properties, was transferred to the pilot plant to test if the plant would now start...... to time. In this work, the particle size distribution, morphology, and filtration rate of wet FGD gypsum formed in a pilot-scale experimental setup, operated in forced oxidation mode, have been studied. The influence of holding tank residence time (10–408 h), solids content (30–169 g/L), and the presence...... to produce low quality gypsum. The crystals formed in the pilot plant, on the basis of the full-scale slurry did, however, show acceptable filtration rates and crystal morphologies closer to the prismatic crystals from after pilot plant experiments with demineralized water. The gypsum slurry filtration rates...

Applicability of industrial wastewater as carbon source for denitrification of a sludge dewatering liquor.

Science.gov (United States)

Chen, Jiazhong; Lee, Yoomin; Oleszkiewicz, Jan A

2013-01-01

The applicability of four industrial waste streams from potato processing, canola processing and oil refining, biodiesel production (glycerol), and glycol as substitutes to methanol and ethanol in denitrification of anaerobically digested sludge dewatering liquor (centrate) was evaluated in bench-scale sequencing batch reactors. It was found that glycerol was the best substitute with the specific denitrification rate (SDNR) of 13 mg NO3-N/(g VSS x h) followed by potato processing wastewater at 12mg NO3-N/(g VSS x h). Both substrates produced faster SDNR than methanol's 10mg NO3-N/(g VSS x h); however, they were inferior to ethanol's 17 mg NO3-N/(g VSS x h). Glycol had SDNR of 8 mg NO3-N/(g VSS x h) and demonstrated a very fast acclimation rate, i.e. the response in increased denitrification rate was visible in three days following glycol addition. Canola processing and oil refining wastewater was considered an inappropriate carbon source due to a low SDNR of 5 mg NO3-N/(g VSS x h) and apparent inhibitory effect on nitrification.

Brown Coal Dewatering Using Poly (Acrylamide-Co-Potassium Acrylic Based Super Absorbent Polymers

Directory of Open Access Journals (Sweden)

Sheila Devasahayam

2015-09-01

Full Text Available With the rising cost of energy and fuel oils, clean coal technologies will continue to play an important role during the transition to a clean energy future. Victorian brown coals have high oxygen and moisture contents and hence low calorific value. This paper presents an alternative non evaporative drying technology for high moisture brown coals based on osmotic dewatering. This involves contacting and mixing brown coal with anionic super absorbent polymers (SAP which are highly crossed linked synthetic co-polymers based on a cross-linked copolymer of acryl amide and potassium acrylate. The paper focuses on evaluating the water absorption potential of SAP in contact with 61% moisture Loy Yang brown coal, under varying SAP dosages for different contact times and conditions. The amount of water present in Loy Yang coal was reduced by approximately 57% during four hours of SAP contact. The extent of SAP brown coal drying is directly proportional to the SAP/coal weight ratio. It is observed that moisture content of fine brown coal can readily be reduced from about 59% to 38% in four hours at a 20% SAP/coal ratio.

Application of a three-dimensional network model to coal dewatering

Energy Technology Data Exchange (ETDEWEB)

Qamar, I.

1986-01-01

A bond-flow correlated network model has been successfully used to calculate equilibrium desaturation curves, single phase permeabilities and two phase flow properties (dewatering curves) for coal filter cakes. A new method of pore volume assignment is presented in which the pore volume occupied by the large pores (which give a capillary pressure less than 0.5 psia) is assigned to the nodes and the rest is distributed to the bonds according to the pore size distribution. The micrographic pore size distribution, used as an input, is determined experimentally. Equilibrium desaturation curves for -32 mesh, -200 mesh and -100 + 200 mesh coal cakes (Pittsburgh Seam Coal), formed with distilled water, have been calculated. The results for six -32 mesh coal cakes formed with surfactants show that the effect of surfactants can be accounted for by modifying one of the model parameters - the entry diameter constant. A correlation is presented to estimate the modified entry diameter constant using experimentally determined surface tension and contact angle values. The size distribution of particles in dispersed state has been correlated with that in the cake which in turn has been correlated with the pore size distribution. An equilibrium desaturation curve has been successfully calculated for -32 mesh Pittsburgh Seam coal using the pore size distribution estimated from the dispersed particle size distribution. Calculated single phase permeabilities, using a bond-flow correlated network and a simple cubic lattice, agree with the experimental values better than a bond-correlated network using a face-centered cubic lattice.

Earthworms facilitate the stabilization of pelletized dewatered sludge through shaping microbial biomass and activity and community.

Science.gov (United States)

Fu, Xiaoyong; Cui, Guangyu; Huang, Kui; Chen, Xuemin; Li, Fusheng; Zhang, Xiaoyu; Li, Fei

2016-03-01

In this study, the effect of earthworms on microbial features during vermicomposting of pelletized dewatered sludge (PDS) was investigated through comparing two degradation systems with and without earthworm E isenia fetida involvement. After 60 days of experimentation, a relatively stable product with low organic matter and high nitrate and phosphorous was harvested when the earthworms were involved. During the process, earthworms could enhance microbial activity and biomass at the initial stage and thus accelerating the rapid decomposition of PDS. The end products of vermicomposting allowed the lower values of bacterial and eukaryotic densities comparison with those of no earthworm addition. In addition, the presence of earthworms modified the bacterial and fungal diversity, making the disappearances of some pathogens and specific decomposing bacteria of recalcitrant substrates in the vermicomposting process. This study evidences that earthworms can facilitate the stabilization of PDS through modifying microbial activity and number and community during vermicomposting.

Satisfação e engajamento no trabalho: docentes temáticos e auxiliares da EAD de universidade privada brasileira/Satisfaction and engagement at work: thematic and assistant teachers for ODL Brazilian private university

OpenAIRE

Cláudia Bomfá Caldas; Universidade Metodista de São Paulo - UMESP; Patrícia Somensari; Universidade Metodista de São Paulo - UMESP; Simone do Nascimento da Costa; Universidade Metodista de São Paulo - UMESP; Mirlene Maria Martins Siqueira; Universidade Metodista de São Paulo - UMESP; Jose Alberto Carvalho dos Santos Claro; Universidade Metodista de São Paulo

2013-01-01

Satisfação e engajamento no trabalho são fenômenos usados como indicadores de saúde no ambiente organizacional e como antecedentes de desempenho profissional. O objetivo deste estudo foi testar quatro hipóteses sobre diferenças e relações entre escores médios de satisfação e engajamento no trabalho de docentes temáticos e auxiliares em Ensino à Distância (EAD) de universidade privada brasileira. Utilizou-se um questionário autoaplicável com 27 itens referentes às escalas de satisfação e engaj...

MÍDIAS DIGITAIS SOCIAIS NO AUXÍLIO AO EAD: As Novas Tecnologias da Informação e da Comunicação como processo facilitador na relação de ensino-aprendizagem

OpenAIRE

Calipo, Valeria

2013-01-01

No presente trabalho investigou-se a adoção por parte das instituições educacionais dos recursos e ferramentas disponíveis nas mídias digitais sociais, que permitem a comunicação síncrona e assíncrona, estimula a comunicação para maior interatividade, dialogicidade e colaboração entre os atores envolvidos no processo ensino-aprendizagem da educação a distância. Para tanto, verificou-se como os alunos que estudam na EAD reagem às novas possibilidades oferecidas com o advento das novas tecnolo...

Characteristics of water obtained by dewatering cyanobacteria-containing sludge formed during drinking water treatment, including C-, N-disinfection byproduct formation.

Science.gov (United States)

Xu, Hangzhou; Pei, Haiyan; Jin, Yan; Xiao, Hongdi; Ma, Chunxia; Sun, Jiongming; Li, Hongmin

2017-03-15

This is the first study to systematically investigate the characteristics of the water obtained by dewatering cyanobacteria-containing sludge generated in the drinking water treatment plant, including formation of C- and N-disinfection by-products (DBPs). Results showed that this 'dewatering water' (DW) had different properties when the sludge was stored at different times. The content of dissolved organic matter (DOM) and microcystins (MCs) in the DW were low when the sludge was treated or disposed of within 4 days; correspondingly, the C-, N-DBP production was also low. However, due to the damage of algal cells to some extent, the DOM and MC levels increased significantly for storage time longer than 4 days; the production of C-, N-DBPs also increased. There were also obvious differences in the characteristics of the DW from sludges generated with different coagulant species. Due to the better protective effect of FeCl 3 and polymeric aluminium ferric chloride (PAFC) flocs, the DOM and MC levels and the production of C-, N-DBPs in the DW with FeCl 3 and PAFC coagulation were lower than those with AlCl 3 coagulation, even though the sludges were stored for the same amount of time. Furthermore, because of the formation of Al and Fe hydroxides, precipitated onto the surface of flocs, the soluble Al and Fe in the DW decreased with increased storage time, especially in the first four days. Overall, this study revealed the trends in variation of DW quality for cyanobacteria-containing sludges formed with different coagulants, then FeCl 3 and PAFC coagulants are recommended and sludge should be treated or disposed of within 4 days. Copyright © 2017 Elsevier Ltd. All rights reserved.

Avaliação da experiência em EaD em um contexto de formação de formadores/Evaluation of Distance Education experience in a context of qualification of trainers

Directory of Open Access Journals (Sweden)

Heloisa Collins

2009-06-01

Full Text Available O objetivo deste artigo é analisar e discutir o que dizem sobre sua experiência em EAD alguns professores que vivenciaram um longo e exigente processo de formação continuada a distância. Para tanto, é apresentado um breve relato da experiência em EAD vivida pelos participantes do curso de formação continuada a distância Práticas de Leitura e Escrita na Contemporaneidade e oferecida uma interpretação de um conjunto de depoimentos de professores-alunos para tentar mostrar que processos de EAD podem, democraticamente, beneficiar diferentes tipos de alunos, gerar ótimos níveis de motivação para a aprendizagem e para o trabalho e oportunizar ricas relações humanas com alto grau de proximidade. A análise dos comentários dos alunos sobre sua aprendizagem e experiência digital faz uso de um aparato teórico proposto pela Linguística Sistêmico-Funcional. A interpretação dos depoimentos é então apoiada em uma análise da avaliatividade expressa na linguagem. Uma vez que realizamos avaliações para contar aos nossos ouvintes ou leitores como nos sentimos em relação a coisas ou pessoas, ou seja, que posições assumimos em relação a elas (Martin, 2003, é possível e importante tentar mapear os tipos de avaliações que os professores-alunos utilizam para falar de sua experiência, dos participantes e do curso. The aim of this paper is to analyze and discuss what some teachers say about a distance learning experience during a long and demanding distance teacher development process. To do this, we first present a report on the experience in the teacher development course Práticas de Leitura e Escrita na Contemporaneidade (Reading and Writing Practices in Contemporaneity; then, we offer an interpretation about a set of evaluative reports the participants made. Our aim is to argue that distance courses can be democratically beneficial to different types of students, motivating for work and study and an opportunity for the

Comparative evaluation of microbial and chemical leaching processes for heavy metal removal from dewatered metal plating sludge

International Nuclear Information System (INIS)

Bayat, Belgin; Sari, Bulent

2010-01-01

The purpose of the study described in this paper was to evaluate the application of bioleaching technique involving Acidithiobacillus ferrooxidans to recover heavy metals (Zn, Cu, Ni, Pb, Cd and Cr) in dewatered metal plating sludge (with no sulfide or sulfate compounds). The effect of some conditional parameters (i.e. pH, oxidation-reduction potential (ORP), sulfate production) and operational parameters (i.e. pulp density of the sludge and agitation time) were investigated in a 3 l completely mixed batch (CMB) reactor. The metal recovery yields in bioleaching were also compared with chemical leaching of the sludge waste using commercial inorganic acids (sulfuric acids and ferric chloride). The leaching of heavy metals increased with decreasing of pH and increasing of ORP and sulfate production during the bioleaching experiment. Optimum pulp density for bioleaching was observed at 2% (w/v), and leaching efficiency decreased with increasing pulp density in bioleaching experiments. Maximum metal solubilization (97% of Zn, 96% of Cu, 93% of Ni, 84% of Pb, 67% of Cd and 34% of Cr) was achieved at pH 2, solids contents of 2% (w/v), and a reaction temperature of 25 ± 2 deg. C during the bioleaching process. The maximum removal efficiencies of 72% and 79% Zn, 70% and 75% Cu, 69% and 73% Ni, 57% and 70% Pb, 55% and 65% Cd, and 11% and 22% Cr were also attained with the chemical leaching using sulfuric acids and ferric chloride, respectively, at pH 2, solids contents of 2% (w/v), and a reaction temperature of 25 ± 2 deg. C during the acid leaching processes. The rates of metal leaching for bioleaching and chemical leaching are well described by a kinetic equation related to time. Although bioleaching generally requires a longer period of operation compared to chemical leaching, it achieves higher removal efficiency for heavy metals. The efficiency of leaching processes can be arranged in descending order as follows: bioleaching > ferric chloride leaching > sulfuric acid

Comparative evaluation of microbial and chemical leaching processes for heavy metal removal from dewatered metal plating sludge

Energy Technology Data Exchange (ETDEWEB)

Bayat, Belgin, E-mail: bbayat@cu.edu.tr [Department of Environmental Engineering, Faculty of Engineering and Architecture, Cukurova University, Balcali, Adana 01330 (Turkey); Sari, Bulent [Department of Environmental Engineering, Faculty of Engineering and Architecture, Cukurova University, Balcali, Adana 01330 (Turkey)

2010-02-15

The purpose of the study described in this paper was to evaluate the application of bioleaching technique involving Acidithiobacillus ferrooxidans to recover heavy metals (Zn, Cu, Ni, Pb, Cd and Cr) in dewatered metal plating sludge (with no sulfide or sulfate compounds). The effect of some conditional parameters (i.e. pH, oxidation-reduction potential (ORP), sulfate production) and operational parameters (i.e. pulp density of the sludge and agitation time) were investigated in a 3 l completely mixed batch (CMB) reactor. The metal recovery yields in bioleaching were also compared with chemical leaching of the sludge waste using commercial inorganic acids (sulfuric acids and ferric chloride). The leaching of heavy metals increased with decreasing of pH and increasing of ORP and sulfate production during the bioleaching experiment. Optimum pulp density for bioleaching was observed at 2% (w/v), and leaching efficiency decreased with increasing pulp density in bioleaching experiments. Maximum metal solubilization (97% of Zn, 96% of Cu, 93% of Ni, 84% of Pb, 67% of Cd and 34% of Cr) was achieved at pH 2, solids contents of 2% (w/v), and a reaction temperature of 25 {+-} 2 deg. C during the bioleaching process. The maximum removal efficiencies of 72% and 79% Zn, 70% and 75% Cu, 69% and 73% Ni, 57% and 70% Pb, 55% and 65% Cd, and 11% and 22% Cr were also attained with the chemical leaching using sulfuric acids and ferric chloride, respectively, at pH 2, solids contents of 2% (w/v), and a reaction temperature of 25 {+-} 2 deg. C during the acid leaching processes. The rates of metal leaching for bioleaching and chemical leaching are well described by a kinetic equation related to time. Although bioleaching generally requires a longer period of operation compared to chemical leaching, it achieves higher removal efficiency for heavy metals. The efficiency of leaching processes can be arranged in descending order as follows: bioleaching > ferric chloride leaching > sulfuric

Arquitectura de un laboratorio remoto desde el enfoque de la formación de ingenieros en ead

Directory of Open Access Journals (Sweden)

Harold Esneider Pérez Waltero

2015-10-01

Full Text Available La Educación Abierta y a Distancia, EaD, soportada en las Tecnologías de la Información y la Comunicación TIC, se proyecta como una de las mejores alternativas para responder de manera pertinente al nuevo contexto de globalización, en procura de generar una sociedad incluyente, desarrollada y competitiva. Sin embargo, es necesario avanzar en el desarrollo de recursos tecnológicos que permitan garantizar procesos formativos de calidad a nivel de Ingeniería bajo esta modalidad, dado que aún persistencuestionamientos al respecto. Son varios los aspectos que se pueden abordar para evidenciar la calidad con la que se puede desarrollar un proceso de formación soportado en las Tecnología de la Informacióny la Comunicación, TIC. Uno de los aspectos estructurales en el proceso formativo de ingenieros en esta metodología, es la práctica de laboratorio; desde esta perspectiva se plantea un escenario real de práctica,aunque remoto, denominado Laboratorio de Acceso Remoto o Laboratorio Remoto (LR. En este sentido, lo que se plantea es el diseño de una arquitectura a nivel de ingeniería para LR, que elimine la barrera de espacio y tiempo, reduzca costos en infraestructura y tenga un mayor grado de universalidad en el acceso, sin sacrificar la calidad que demanda el ejercicio riguroso de la práctica de laboratorios en la formación del Ingeniero.

Effect of Long-Term Freezing and Freeze–Thaw Cycles on Indigenous and Inoculated Microorganisms in Dewatered Blackwater

DEFF Research Database (Denmark)

Gunnarsdottir, Ragnhildur; Müller, Karoline; Jensen, Pernille Erland

2012-01-01

Wastewater treatment in many Arctic regions is inadequate, even nonexisting. Natural freezing of wastewater in those areas may be beneficial for reduction of microorganisms. The aim of this study was to investigate the effect of long-term freezing, and repeated freezing and thawing, on indigenous...... coliforms, fecal streptococci, and antibiotic-resistant (AR) bacteria, and inoculated Salmonella Enteriditis and E. coli bacteriophage ΦX174 in dewatered blackwater. At the end of the long-term freezing experiment (10 months), an MPN recovery study was done, including the microbial groups that had shown...... the largest reduction, using tryptone soy broth at incubation temperatures of 10 and 20 °C overnight for the coliforms and AR bacteria, and buffered peptone water at incubation temperature of 37 °C for 18–20 h for Salmonella. Fecal streptococci were more resistant to long-term freezing than the coliform group...

Study of dielectric materials irradiated with electron beam by using the Pulsed Electro-Acoustic (PEA) method

International Nuclear Information System (INIS)

Nguyen, Xuan Truong

2014-01-01

Dielectric materials are frequently used as electrical insulators in spatial applications. Due to their dielectric nature, these dielectrics are likely to accumulate electric charges during their service. Under certain critical conditions, these internal or surface space charges can lead to an electrostatic surface discharge. To understand these phenomena, an experimental device has been developed in the laboratory. This device allows us to simulate the electronic irradiation conditions encountered in space. The aim of our study is to characterize the electrical behavior of insulating materials irradiated by electron beam, to investigate charge storage and transport phenomena and anticipate electrostatic discharges. In this work, the device based on the Pulsed Electro-Acoustic (PEA) technique has been chosen. It has been implanted in the irradiation chamber. It allows us to obtain the spatial distribution of charges injected between two periods of irradiation and during relaxation. However the PEA method offers a limited resolution and does not allow the detection of injected charges when they are too close to the surface. First, we performed a parameters signal processing analysis that we will call the spreading factor and the resolution factor. The preliminary study post-irradiation in air of experimental measurements showed that the resolution factor choice is important for the analysis and interpretation of the signal when the space charge is localized near the surface. Then, a comparison to the spreading parameter used in some deconvolution technique was established. In the second time, space charge distribution measurements in vacuum have been carried out on Poly Tetra Fluoro Ethylene (PTFE) films irradiated by an electron beam in the range [10-100] keV. Results from irradiation periods with increasing energies [10 keV → 100 keV] of the electron beam have been compared with results from irradiation periods with decreasing energies [100 keV → 10 keV]. In

Early liver allograft dysfunction: risk factors, clinical course and outcomes

Directory of Open Access Journals (Sweden)

Ya. G. Moysyuk

2016-01-01

Full Text Available Early liver allograft dysfunction (EAD is associated with a high incidence of graft loss and patient mortality in the first 6 weeks after orthotopic liver transplantation (OLT.The aim of this retrospective single-center study is to identify the risk factors of EAD and to compare the short- and long-term results in EAD and non-EAD groups.Materials and methods. The results of 213 consecutive deceased donor liver transplantations performed between December 2004 and February 2015 were included in the analysis. Indications for OLT were non-viral liver cirrhosis in 52% of cases, viral hepatitis C or B in 34 %, hepatocellular carcinoma in 8 %; retransplantations were performed in 6% of cases due to previous liver graft dysfunction. EAD was defined by Olthoff criteria (Olthoff et al., 2010.Results. Overall incidence of EAD was 41.3%, including 5.6% of primary non-function grafts (PNF, i.e. irreversible EAD. No significant differences between EAD and non-EAD groups were seen either among donors in their age, gender, cause of death, bilirubin, plasma sodium level, aminotransferases aktivity, or among the recipients in their age, gender, body mass index, MELD. Retransplantation, donor time on mechanical ventilation in the intensive care unit for more than 2 days, highrisk donor category, transplant surgery duration more than 9.5 hours, and cold ischemia time (CIT > 8 hours were independent significant risk factors of EAD in a multivariate model. A 42-day mortality rates were 18.2% in EAD group (mostly due to PNF without urgent retransplantanion in 9.1%, and 0% in non-EAD group. Long-term results in EAD group were also significantly poorer: 1-, 5-, and 10-year graft survival rates were 74%, 68%, and 64%, respectively, versus 96%, 90%, and 83% in non-EAD group, Log-rank p = 0.0001.Conclusion. EAD significantly (≈ 20% decreases the short-term graft and patient survival rates. Meanwhile, a reversible EAD has no impact on long-term results

Development of Graft Copolymer Flocculant Based on Acrylamide and Acrylic Acid for the dewatering of coal

International Nuclear Information System (INIS)

Mahmoud, G.A.; Abdel Khalek, M.A

2012-01-01

Most coal preparation processes were carried out in water medium. The water content of coal product has a negative impact on handling and specific energy value. The moisture content may be attributed to the proportion of fine coal, which presents the greatest dewatering problem. A novel polymeric flocculant has been developed by graft copolymerization of acrylamide (AAm) with acrylic acid (AAc) using gamma irradiation technique. The grafted copol621621ymer P(AAm/AAc) was characterized by Fourier-transform infrared spectroscopy (FTIR), and thermo-gravimetric analysis (TGA). The effects of reaction parameters, such as total absorbed dose, and monomer concentration on grafting yield were investigated. The flocculation performance of the graft copolymer P(AAm/AAc) was investigated in coal suspension. It was observed that the grafting ratio was one of the key factors for the flocculating effects. The copolymers with various grafting ratios showed different flocculating properties. It was found that as the grafting ratio increased, the flocculating effect also increased. The flocculation performance of the grafted copolymer was better than that of the commercial flocculant, poly-acrylamide (Magnafloc 1011).

Mine dewatering and impact assessment in an arid area: Case of Gulf region.

Science.gov (United States)

Yihdego, Yohannes; Drury, Len

2016-11-01

Analytical and empirical solution coupled with water balance method were used to predict the ground water inflow to a mine pit excavated below the water table, final pit lake level/recovery and radius of influence, through long-term and time variant simulations. The solution considers the effect of decreased saturated thickness near the pit walls, distributed recharge to the water table and upward flow through the pit bottom. The approach is flexible to accommodate the anisotropy/heterogeneity of the real world. Final pit void water level was assessed through scenarios to know whether it will be consumed by evaporation and a shallow lake will form or not. The optimised radius of influence was estimated which is considered as crucial information in relation to the engineering aspects of mine planning and sustainable development of the mine area. Time-transient inflow over a period of time was estimated using solutions, including analytical element method (AEM). Their primary value is in providing estimates of pit inflow rates to be used in the mine dewatering. Inflow estimation and recovery helps whether there is water to supplement the demand and if there is any recovery issue to be dealt with in relation to surface and groundwater quality/eco-system, environmental evaluations and mitigation. Therefore, this method is good at informing decision makers in assessing the effects of mining operations and developing an appropriate water management strategy.

Design and construction of solidification and dewatering facility at Alabama Power Company's Farley Nuclear Plant

International Nuclear Information System (INIS)

Farnsworth, P.

1988-01-01

The approximate total cost of the structure and supporting piping systems is estimated to be 4.1 million dollars. Total dose savings per year could be as high as 70 man Rem for resin processing alone. The ability to store refueling equipment, process contaminated oils, load and unload trucks and containers regardless of weather conditions and support repair work on equipment greatly enhances the cost effectiveness of the project. It will take at least one year of operation of the facility to accurately assess the true cost savings to Alabama Power Company. The morale factor for the Waste and Decon Group has escalated measurably due to the dose reduction to our personnel. Plant and company management are well pleased due to the possibility of a spill or release to the environment has been eliminated which was on intangible cost. Facility construction has been completed as of this date and resin transfer anticipated within the next few days. Some of the problems encountered in planning and constructing this solidification and dewatering facility are presented. A safety evaluation for the facility is included in the appendix

Dewatering of Chlorella pyrenoidosa using diatomite dynamic membrane: filtration performance, membrane fouling and cake behavior.

Science.gov (United States)

Zhang, Yalei; Zhao, Yangying; Chu, Huaqiang; Zhou, Xuefei; Dong, Bingzhi

2014-01-01

The diatomite dynamic membrane (DDM) was utilized to dewater Chlorella pyrenoidosa of 2 g dry weight/L under continuous-flow mode, whose ultimate algae concentration ranged from 43 g to 22 g dry weight/L of different culture time. The stable flux of DDM could reach 30 L/m(2) h over a 24 h operation time without backwash. Influences of extracellular organic matters (EOM) on filtration behavior and membrane fouling were studied. The DDM was divided into three sub-layers, the slime layer, the algae layer and the diatomite layer from the outside to the inside of the cake layer based on components and morphologies. It was found that EOM caused membrane fouling by accumulating in the slime and algae layers. The DDM intercepted polysaccharides, protein-like substances, humic-like substances and some low-MW organics. Proteins were indicated the major membrane foulants with increased protein/polysaccharide ratio from the slime layer to the diatomite layer as culture time increased. This method could be applied to subsequent treatment of microalgae coupling technology of wastewater treatment or microalgae harvesting for producing biofuel. Copyright © 2013 Elsevier B.V. All rights reserved.

Optimization of volatile fatty acid production with co-substrate of food wastes and dewatered excess sludge using response surface methodology.

Science.gov (United States)

Hong, Chen; Haiyun, Wu

2010-07-01

Central-composite design (CCD) and response surface methodology (RSM) were used to optimize the parameters of volatile fatty acid (VFA) production from food wastes and dewatered excess sludge in a semi-continuous process. The effects of four variables (food wastes composition in the co-substrate of food wastes and excess sludge, hydraulic retention time (HRT), organic loading rate (OLR), and pH) on acidogenesis were evaluated individually and interactively. The optimum condition derived via RSM was food wastes composition, 88.03%; HRT, 8.92 days; OLR, 8.31 g VSS/ld; and pH 6.99. The experimental VFA concentration was 29,099 mg/l under this optimum condition, which was well in agreement with the predicted value of 28,000 mg/l. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Feasibility of vermicomposting dewatered sludge from paper mills using Perionyx excavatus

Directory of Open Access Journals (Sweden)

Puspanjali Sonowal

2013-06-01

Full Text Available India has a large network of pulp and paper mills of varying capacity. On an industrial scale the sludge from paper and pulp mills is disposed of either as landfill or incinerated. Both methods result in the loss of a valuable resource and have obvious environmental and economic disadvantages. The solid waste from pulp and paper mills is a source of organic matter and its proper disposal and management is the responsibility of the industry. As composting/vermicomposting could be used to transform this waste trials were carried out to determine the feasibility of converting dewatered sludge (DS into a value added end product using an earthworm, Perionyx excavatus. The vermicomposting of the waste resulted in an increase in its electrical conductivity (EC, ash content, total nitrogen (TN, total phosphorous (TP and available phosphorous (AP, respectively, and a decrease in total organic carbon (TOC, biochemical oxygen demand (BOD, chemical oxygen demand (COD, oxygen uptake rate (OUR and evolution of carbon dioxide (CO2. Overall, the best treatment was T5 in which there was a 76.1% increase in TP, 58.7% in TN, 74.5% decrease in TOC , and a reduction of 6.7 fold in the production of CO2 and 10.7 fold in BOD, respectively. Our trials demonstrate that vermicomposting using an epigeic earthworm, Perionyx excavatus, is an alternate and environmentally safe way of recycling paper mill sludge if it is mixed with an appropriate amount of cow dung and food processing waste. Overall T5 was the best combination of paper mill sludge and waste for vermicomposting followed by T3, T2, T4 and T1, respectively.

Effects of therapeutic plasma exchange on early allograft dysfunction after liver transplantation.

Science.gov (United States)

Choe, Wonho; Kwon, Seog-Woon; Kim, Sung-Soo; Hwang, Shin; Song, Gi-Won; Lee, Sung-Gyu

2017-06-01

Early allograft dysfunction (EAD) is a serious complication of liver transplantation (LT) and is associated with graft failure, which can result in patient mortality. Due to the shortage of organs for retransplantation, only a small proportion of EAD patients undergo retransplantation. Thus, liver support is needed for most patients with EAD. We evaluated the effects of therapeutic plasma exchange (TPE) in EAD patients. EAD was defined as a sustained hyperbilirubinemia (≥10 mg/dL) within 30 days of LT without concurrent biliary complications. In a 13-year period, 107 EAD patients underwent TPE while 36 EAD patients did not. We investigated the laboratory and clinical outcomes of TPE and non-TPE groups. The TPE group showed 1-month and 1-year survival rates of 82.2% and 53.8%, respectively, whereas the non-TPE group showed 58.3% and 22.2%, respectively. In TPE group, statistically significant decreases (P higher INR on the day of EAD onset increased the risk. TPE effectively removed plasma bilirubin and improved coagulation function in EAD patients, with higher survival in the TPE group than in the non-TPE group. TPE may be an effective liver support for EAD patients. J. Clin. Apheresis 32:147-153, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Effect of biodegradation on the consolidation properties of a dewatered municipal sewage sludge.

Science.gov (United States)

O'Kelly, Brendan C

2008-01-01

The effect of biodegradation on the consolidation characteristics of an anaerobically digested, dewatered municipal sewage sludge was studied. Maintained-load oedometer consolidation tests that included measurement of the pore fluid pressure response were conducted on moderately degraded sludge material and saturated bulk samples that had been stored under static conditions and allowed to anaerobically biodegrade further (simulating what would happen in an actual sewage sludge monofill or lagoon condition). Strongly degraded sludge material was produced after a storage period of 13 years at ambient temperatures of 5-15 degrees C, with the total volatile solids reducing from initially 70% to 55%. The sludge materials were highly compressible, although impermeable for practical purposes. Primary consolidation generally occurred very slowly, which was attributed to the microstructure of the solid phase, the composition and viscosity of the pore fluid, ongoing biodegradation and the high organic contents. The coefficient of primary consolidation values decreased from initially about 0.35m2/yr to 0.003-0.03m2/yr with increasing effective stress (sigmav'=3-100kPa). Initially, the strongly degraded sludge material was slightly more permeable, although both the moderately and strongly degraded materials became impermeable for practical purposes (k=10(-9)-10(-12)m/s) below about 650% and 450% water contents, respectively. Secondary compression became more dominant with increasing effective stress with a mean secondary compression index (Calphae) value of 0.9 measured for both the moderately and strongly degraded materials.

The effect of the configuration of a single electrode corona discharge on its acoustic characteristics

Science.gov (United States)

Zhu, Xinlei; Zhang, Liancheng; Huang, Yifan; Wang, Jin; Liu, Zhen; Yan, Keping

2017-07-01

A new sparker system based on pulsed spark discharge with a single electrode has already been utilized for oceanic seismic exploration. However, the electro-acoustic energy efficiency of this system is lower than that of arc discharge based systems. A simple electrode structure was investigated in order to improve the electro-acoustic energy efficiency of the spark discharge. Experiments were carried out on an experimental setup with discharge in water driven by a pulsed power source. The voltage-current waveform, acoustic signal and bubble oscillation were recorded when the relative position of the electrode varied. The electro-acoustic energy efficiency was also calculated. The load voltage had a saltation for the invaginated electrode tip, namely an obvious voltage remnant. The more the electrode tip was invaginated, the larger the pressure peaks and first period became. The results show that electrode recessing into the insulating layer is a simple and effective way to improve the electro-acoustic energy efficiency from 2% to about 4%.

Uma breve revisão histórica do papel das videoaulas na EaD no Brasil DOI:10.5007/1984-8420.2010v11n2p53

Directory of Open Access Journals (Sweden)

Aline Cassol Daga

2010-05-01

Full Text Available Este artigo tem como objetivo refletir sobre o papel que tem ocupado a produção e veiculação de videoaulas dentro do panorama da Educação a Distância no Brasil, principalmente no contexto de programas nacionais destinados à educação de jovens e adultos, tanto no que concerne à formação discente, quanto no que concerne à formação continuada de professores em atuação nas redes públicas de ensino. Para tanto, o artigo se divide em dois capítulos: no primeiro capítulo revisitamos a trajetória do programa Telecurso em suas três versões – Telecurso 2º grau e Telecurso 1º Grau, Telecurso 2000, Novo Telecurso; no segundo capítulo discutimos os programas de EaD vinculados à formação do professor em serviço.

Paste pumping and deposition field trials and concepts on Syncrude's dewatered mature fine tailings MFT centrifuge cake

Energy Technology Data Exchange (ETDEWEB)

Lahaie, R. [Syncrude Canada Ltd., Edmonton, AB (Canada); Ahmed, I.; Labelle, M.; Brown, R. [Golder Paste Technology, Sudbury, ON (Canada)

2009-07-01

This presentation discussed a paste pumping and deposition field study conducted on dewatered mature fine tailings (MFT) located at Syncrude's Mildred Lake operation. Bench scale rheological examinations of centrifuge cakes and design field testing are used to determine the pumpability of MFT centrifuge cakes. The study included a transportation assessment for the conveyor and positive displacement pumps and pipelines, as well as geotechnical and environmental analyses of bulk materials. Flocculant optimization and centrifuge operational parameter assessments were conducted. Pressure differential and flow rate data were captured in the field studies in order to determine pipeline friction loss. The study showed that pipe friction factors can be obtained using the Bingham plastic model. A natural deposition angle was determined for the MFT centrifuged cake. The study showed that the cake must be sheared in order to reduce yield stress before pumping. It was concluded that displacement pumps can be used to reduced pipeline friction factors. tabs., figs.

Female-biased attraction of Oriental fruit fly, bactrocera dorsalis (Hendel), to a blend of host fruit volatiles from Terminalia catappa L.

Science.gov (United States)

Siderhurst, Matthew S; Jang, Eric B

2006-11-01

Coupled gas chromatography-electroantennogram detection (GC-EAD) analysis of volatiles from tropical almond fruit, Terminalia catappa L., revealed 22 compounds that were detected by antennae of oriental fruit fly females, Bactrocera dorsalis (Hendel). Both solid-phase microextraction (SPME) and Porapak Q were used for sampling odors in fruit headspace, with SPME collections producing larger EAD responses from a greater number of compounds. Geranyl acetate and methyl eugenol elicited the largest EAD responses. A synthetic blend containing SPME collected, EAD stimulatory compounds showed female-biased attraction in laboratory wind tunnel bioassays, but heavily male-biased trap captures in a larger olfactometer arena. A nine-component subset of compounds eliciting relatively small EAD responses (EAD minor) and consisting of equal parts ethanol, ethyl acetate, ethyl hexanoate, hexyl acetate, linalyl acetate, ethyl nonanate, nonyl acetate, ethyl cinnamate, and (E)-beta-farnesene, attracted mainly females. This EAD minor blend was as attractive to females and much less attractive to males when compared to torula yeast in field cage experiments using glass McPhail traps. Similar results were obtained with outdoor rotating olfactometer tests in which the EAD minor blend was almost completely inactive for males.

An overview of mineral dust modeling over East Asia

Science.gov (United States)

Chen, Siyu; Huang, Jianping; Qian, Yun; Zhao, Chun; Kang, Litai; Yang, Ben; Wang, Yong; Liu, Yuzhi; Yuan, Tiangang; Wang, Tianhe; Ma, Xiaojun; Zhang, Guolong

2017-08-01

East Asian dust (EAD) exerts considerable impacts on the energy balance and climate/climate change of the earth system through its influence on solar and terrestrial radiation, cloud properties, and precipitation efficiency. Providing an accurate description of the life cycle and climate effects of EAD is therefore critical to better understanding of climate change and socioeconomic development in East Asia and even worldwide. Dust modeling has undergone substantial development since the late 1990s, associated with improved understanding of the role of EAD in the earth system. Here, we review the achievements and progress made in recent decades in terms of dust modeling research, including dust emissions, long-range transport, radiative forcing (RF), and climate effects of dust particles over East Asia. Numerous efforts in dust/EAD modeling have been directed towards furnishing more sophisticated physical and chemical processes into the models on higher spatial resolutions. Meanwhile, more systematic observations and more advanced retrieval methods for instruments that address EAD related science issues have made it possible to evaluate model results and quantify the role of EAD in the earth system, and to further reduce the uncertainties in EAD simulations. Though much progress has been made, large discrepancies and knowledge gaps still exist among EAD simulations. The deficiencies and limitations that pertain to the performance of the EAD simulations referred to in the present study are also discussed.

Attitudes of Veterinary Teaching Staff and Exposure of Veterinary Students to Early-Age Desexing, with Review of Current Early-Age Desexing Literature

Directory of Open Access Journals (Sweden)

Alannah Jupe

2017-12-01

Full Text Available Approximately 50% of cats admitted to Australian shelters are kittens, and 26% of dogs are puppies, and, particularly for cats, euthanasia rates are often high. Cats can be pregnant by 4 months of age, yet the traditional desexing age is 5–6 months, and studies in Australasia and Nth America reveal that only a minority of veterinarians routinely perform early age desexing (EAD of cats or dogs, suggesting they are not graduating with these skills. This study aimed to describe the attitudes of veterinary teaching staff in Australian and New Zealand universities towards EAD, and to determine if these changed from 2008 to 2015. It also aimed to identify students’ practical exposure to EAD. Most (64% of the 25 participants in 2015 did not advocate EAD in their teaching and, in their personal opinion, only 32% advocated it for cats. Concerns related to EAD cited by staff included anesthetic risk, orthopedic problems, hypoglycemia, and, in female dogs, urinary incontinence. Those who advocated EAD cited benefits of population control, ease of surgery and behavioral benefits. Only three of the eight universities provided a majority of students with an opportunity to gain exposure to EAD procedures before graduation, and in two of these, most students had an opportunity to perform EAD. In conclusion, most veterinary students in Australia and New Zealand are not graduating with the knowledge or skills to perform EAD, and have little opportunity while at university to gain practical exposure. Welfare agencies could partner with universities to enable students to experience EAD.

Attitudes of Veterinary Teaching Staff and Exposure of Veterinary Students to Early-Age Desexing, with Review of Current Early-Age Desexing Literature.

Science.gov (United States)

Jupe, Alannah; Rand, Jacquie; Morton, John; Fleming, Sophie

2017-12-25

Approximately 50% of cats admitted to Australian shelters are kittens, and 26% of dogs are puppies, and, particularly for cats, euthanasia rates are often high. Cats can be pregnant by 4 months of age, yet the traditional desexing age is 5-6 months, and studies in Australasia and Nth America reveal that only a minority of veterinarians routinely perform early age desexing (EAD) of cats or dogs, suggesting they are not graduating with these skills. This study aimed to describe the attitudes of veterinary teaching staff in Australian and New Zealand universities towards EAD, and to determine if these changed from 2008 to 2015. It also aimed to identify students' practical exposure to EAD. Most (64%) of the 25 participants in 2015 did not advocate EAD in their teaching and, in their personal opinion, only 32% advocated it for cats. Concerns related to EAD cited by staff included anesthetic risk, orthopedic problems, hypoglycemia, and, in female dogs, urinary incontinence. Those who advocated EAD cited benefits of population control, ease of surgery and behavioral benefits. Only three of the eight universities provided a majority of students with an opportunity to gain exposure to EAD procedures before graduation, and in two of these, most students had an opportunity to perform EAD. In conclusion, most veterinary students in Australia and New Zealand are not graduating with the knowledge or skills to perform EAD, and have little opportunity while at university to gain practical exposure. Welfare agencies could partner with universities to enable students to experience EAD.

Period doubling cascades of limit cycles in cardiac action potential models as precursors to chaotic early Afterdepolarizations.

Science.gov (United States)

Kügler, Philipp; Bulelzai, M A K; Erhardt, André H

2017-04-04

Early afterdepolarizations (EADs) are pathological voltage oscillations during the repolarization phase of cardiac action potentials (APs). EADs are caused by drugs, oxidative stress or ion channel disease, and they are considered as potential precursors to cardiac arrhythmias in recent attempts to redefine the cardiac drug safety paradigm. The irregular behaviour of EADs observed in experiments has been previously attributed to chaotic EAD dynamics under periodic pacing, made possible by a homoclinic bifurcation in the fast subsystem of the deterministic AP system of differential equations. In this article we demonstrate that a homoclinic bifurcation in the fast subsystem of the action potential model is neither a necessary nor a sufficient condition for the genesis of chaotic EADs. We rather argue that a cascade of period doubling (PD) bifurcations of limit cycles in the full AP system paves the way to chaotic EAD dynamics across a variety of models including a) periodically paced and spontaneously active cardiomyocytes, b) periodically paced and non-active cardiomyocytes as well as c) unpaced and spontaneously active cardiomyocytes. Furthermore, our bifurcation analysis reveals that chaotic EAD dynamics may coexist in a stable manner with fully regular AP dynamics, where only the initial conditions decide which type of dynamics is displayed. EADs are a potential source of cardiac arrhythmias and hence are of relevance both from the viewpoint of drug cardiotoxicity testing and the treatment of cardiomyopathies. The model-independent association of chaotic EADs with period doubling cascades of limit cycles introduced in this article opens novel opportunities to study chaotic EADs by means of bifurcation control theory and inverse bifurcation analysis. Furthermore, our results may shed new light on the synchronization and propagation of chaotic EADs in homogeneous and heterogeneous multicellular and cardiac tissue preparations.

Differences of neuroimaging between early-onset and late-onset alzheimer-type dementia

International Nuclear Information System (INIS)

Hanyu, Haruo; Nakano, Seigo; Abe, Shin'e; Arai, Hisayuki; Iwamoto, Toshihiko; Takasaki, Masaru

1995-01-01

Several studies have shown that the symptomatology and the neuropathological and neurochemical changes of early-onset Alzheimer's disease (EAD) differ from those of late-onset Alzheimer's disease (LAD). The aim of the present study is to examine differences in SPECT and MRI findings between EAD and LAD. Cerebral blood flow and patterns on SPECT, and deep white matter lesions and cerebral atrophy on MRI in 17 patients with EAD were compared with 30 patients with LAD without cerebrovascular risk factors. Temporoparietal activity ratio, divided by cerebellum, on SPECT imaging in patients with EAD was significantly lower than in patients with LAD. In a qualitative assessment of perfusion patterns, bilateral temporoparietal hypoperfusion, which is typical in AD, was seen more frequently in patients with EAD than in those with LAD. Among white matter changes in MRI, the score of white matter hyperintensity was significantly higher in LAD than in EAD patients. However, there was no significant difference between periventricular hyperintensity scores. Though ventricular enlargement did not differ significantly in EAD and LAD, cortical atrophy scores in LAD were significantly higher than in EAD. Cortical atrophy scores were significantly higher in patients with atypical perfusion patterns on SPECT (e.g. global hypoperfusion in addition to temporoparietal change) than in patients with typical perfusion pattern. These results indicate that functional and morphological imagings in LAD differ with those in EAD, probably due to less-prominent neuropathological degeneration combined with age-related alterations. (author)

Differences of neuroimaging between early-onset and late-onset alzheimer-type dementia

Energy Technology Data Exchange (ETDEWEB)

Hanyu, Haruo; Nakano, Seigo; Abe, Shin` e; Arai, Hisayuki; Iwamoto, Toshihiko; Takasaki, Masaru [Tokyo Medical Coll. (Japan)

1995-10-01

Several studies have shown that the symptomatology and the neuropathological and neurochemical changes of early-onset Alzheimer`s disease (EAD) differ from those of late-onset Alzheimer`s disease (LAD). The aim of the present study is to examine differences in SPECT and MRI findings between EAD and LAD. Cerebral blood flow and patterns on SPECT, and deep white matter lesions and cerebral atrophy on MRI in 17 patients with EAD were compared with 30 patients with LAD without cerebrovascular risk factors. Temporoparietal activity ratio, divided by cerebellum, on SPECT imaging in patients with EAD was significantly lower than in patients with LAD. In a qualitative assessment of perfusion patterns, bilateral temporoparietal hypoperfusion, which is typical in AD, was seen more frequently in patients with EAD than in those with LAD. Among white matter changes in MRI, the score of white matter hyperintensity was significantly higher in LAD than in EAD patients. However, there was no significant difference between periventricular hyperintensity scores. Though ventricular enlargement did not differ significantly in EAD and LAD, cortical atrophy scores in LAD were significantly higher than in EAD. Cortical atrophy scores were significantly higher in patients with atypical perfusion patterns on SPECT (e.g. global hypoperfusion in addition to temporoparietal change) than in patients with typical perfusion pattern. These results indicate that functional and morphological imagings in LAD differ with those in EAD, probably due to less-prominent neuropathological degeneration combined with age-related alterations. (author).

Groundwater Sustainability through a Novel Dewatering Technology

Science.gov (United States)

Jin, Y.; Holzbecher, E.; Ebneth, S.

2012-12-01

Groundwater plays a key role in the hydrologic cycle and ecosystem balances. Over the past decades, groundwater is intensively extracted in order to keep construction or mining sites dry. For the latter purpose the pumped water is usually discharged into a nearby surface water body or injected into an aquifer distant from the abstraction sites. As a result, aquifers are depleted and the local eco-system is disrupted as a consequence of falling groundwater tables. Given ongoing pressure on aquifer from abstraction sites, it is vital to bring up adequate attention on groundwater conservation. We demonstrate a novel technique, Düsensauginfiltration (DSI, translated as 'nozzel-suction-infiltration'), which avoids water conveyance but still lowers the groundwater table locally. The method combines abstraction of groundwater at the upper part of the aquifer with injection in the same borehole, but at a greater depth. Hence no water is withdrawn from the system. The method is already used practically in Germany, Netherlands, and China, however, it is not yet fully scientifically understood and evaluated. Currently, two tests sites in Germany, for single and multi well respectively, are selected, at which the DSI technology is currently examined. The project is cooperated with a leading dewatering company (Hoelscher Wasserbau GmbH) and funded by Deutsche Bundesstiftung Umwelt (DBU). To provide the basic principle of the method, we present numerical models solving the differential equation, which is derived from Darcy's Law and mass conservation, describing groundwater flow. We set up stationary numerical models in 2D (vertical cross section for single well case) and 3D (multi well case and/or when ambient groundwater flow is considered) using COMSOL Multiphysics. Since our model region only involves the saturated part of the unconfined aquifer, the numerical model solves a free boundary problem using hydraulic pressure as unknown variable. Two physical modes are included

An Experimental Study on Axial Temperature Distribution of Combustion of Dewatered Poultry Sludge in Fluidized bed combustor

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Abbas A.H.

2016-01-01

Full Text Available A laboratory scale bubbling fluidized bed combustor was designed and fabricated to study the combustion of dewatered poultry sludge at different operational parameters. This paper present a study on the influence of equivalent ratio, secondary to primary air ratio and the fuel feed rate on the temperature distribution along the combustor. The equivalent ratio has been changed between 0.8 to 1.4% under poultry sludge feed rate of 10 kg/h and from 0.8 to 1 under poultry sludge feed rate of 15 kg/h. The secondary to primary air ratio was varied from 0.1 to 0.5 at 0.65 m injection height and 1.25 equivalent ratio. The results showed that these factors had a significant influence on the combustion characteristics of poultry sludge. The temperature distribution along the combustor was found to be strongly dependent on the fuel feed rate and the equivalent ratio and it increased when these two factors increased. However, the secondary air ratio increased the temperature in the lower region of the combustor while no significant effect was observed at the upper region of the combustor. The results suggested that the poultry sludge can be used as a fuel with high thermal combustor efficiency.

The Effect of Electrical Impedance Matching on the Electromechanical Characteristics of Sandwiched Piezoelectric Ultrasonic Transducers

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Yuan Yang

2017-12-01

Full Text Available For achieving the power maximum transmission, the electrical impedance matching (EIM for piezoelectric ultrasonic transducers is highly required. In this paper, the effect of EIM networks on the electromechanical characteristics of sandwiched piezoelectric ultrasonic transducers is investigated in time and frequency domains, based on the PSpice model of single sandwiched piezoelectric ultrasonic transducer. The above-mentioned EIM networks include, series capacitance and parallel inductance (I type and series inductance and parallel capacitance (II type. It is shown that when I and II type EIM networks are used, the resonance and anti-resonance frequencies and the received signal tailing are decreased; II type makes the electro-acoustic power ratio and the signal tailing smaller whereas it makes the electro-acoustic gain ratio larger at resonance frequency. In addition, I type makes the effective electromechanical coupling coefficient increase and II type makes it decrease; II type make the power spectral density at resonance frequency more dramatically increased. Specially, the electro-acoustic power ratio has maximum value near anti-resonance frequency, while the electro-acoustic gain ratio has maximum value near resonance frequency. It can be found that the theoretically analyzed results have good consistency with the measured ones.

Validation of a current definition of early allograft dysfunction in liver transplant recipients and analysis of risk factors.

Science.gov (United States)

Olthoff, Kim M; Kulik, Laura; Samstein, Benjamin; Kaminski, Mary; Abecassis, Michael; Emond, Jean; Shaked, Abraham; Christie, Jason D

2010-08-01

Translational studies in liver transplantation often require an endpoint of graft function or dysfunction beyond graft loss. Prior definitions of early allograft dysfunction (EAD) vary, and none have been validated in a large multicenter population in the Model for End-Stage Liver Disease (MELD) era. We examined an updated definition of EAD to validate previously used criteria, and correlated this definition with graft and patient outcome. We performed a cohort study of 300 deceased donor liver transplants at 3 U.S. programs. EAD was defined as the presence of one or more of the following previously defined postoperative laboratory analyses reflective of liver injury and function: bilirubin >or=10mg/dL on day 7, international normalized ratio >or=1.6 on day 7, and alanine or aspartate aminotransferases >2000 IU/L within the first 7 days. To assess predictive validity, the EAD definition was tested for association with graft and patient survival. Risk factors for EAD were assessed using multivariable logistic regression. Overall incidence of EAD was 23.2%. Most grafts met the definition with increased bilirubin at day 7 or high levels of aminotransferases. Of recipients meeting the EAD definition, 18.8% died, as opposed to 1.8% of recipients without EAD (relative risk = 10.7 [95% confidence interval: 3.6, 31.9] P definition of EAD using objective posttransplant criteria identified a 23% incidence, and was highly associated with graft loss and patient mortality, validating previously published criteria. This definition can be used as an endpoint in translational studies aiming to identify mechanistic pathways leading to a subgroup of liver grafts with clinical expression of suboptimal function. (c) 2010 AASLD.

78 FR 24041 - Airworthiness Directives; Eurocopter France Helicopters

Science.gov (United States)

2013-04-24

... revising the RFM to reduce the V NE indicated airspeed (IAS) limitation. It also requires, before further... EAD placard limited TAS, while the placard in our EAD limited IAS. Actions Since Existing EAD Was... 2012-207-E, changes the airspeed limitation from TAS to IAS, and requires inserting a temporary engine...

Longitudinal Modes along Thin Piezoelectric Waveguides for Liquid Sensing Applications

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Cinzia Caliendo

2015-06-01

Full Text Available The propagation of longitudinally polarized acoustic modes along thin piezoelectric plates (BN, ZnO, InN, AlN and GaN is theoretically studied, aiming at the design of high frequency electroacoustic devices suitable for work in liquid environments. The investigation of the acoustic field profile across the plate revealed the presence of longitudinally polarized Lamb modes, travelling at velocities close to that of the longitudinal bulk acoustic wave propagating in the same direction. Such waves are suitable for the implementation of high-frequency, low-loss electroacoustic devices operating in liquid environments. The time-averaged power flow density, the phase velocity and the electroacoustic coupling coefficient K2 dispersion curves were studied, for the first (S0 and four higher order (S1, S2, S3, S4 symmetrical modes for different electrical boundary conditions. Two electroacoustic coupling configurations were investigated, based on interdigitated transducers, with or without a metal floating electrode at the opposite plate surface. Enhanced performances, such as a K2 as high as 8.5% and a phase velocity as high as 16,700 m/s, were demostrated for the ZnO- and BN-based waveguides, as an example. The relative velocity changes, and the inertial and viscous sensitivities of the first symmetric and anti-symmetric mode, S0 and A0, propagating along thin plates bordered by a viscous liquid were derived using the perturbation approach. The present study highlights the feasibility of the piezoelectric waveguides to the development of high-frequency, integrated-circuits compatible electroacoustic devices suitable for working in liquid environment.

The impact of pumped water from a de-watered Magnesian limestone quarry on an adjacent wetland: Thrislington, County Durham, UK

International Nuclear Information System (INIS)

Mayes, W.M.; Large, A.R.G.; Younger, P.L.

2005-01-01

Although quarrying is often cited as a potential threat to wetland systems, there is a lack of relevant, quantitative case studies in the literature. The impact of pumped groundwater discharged from a quarry into a wetland area was assessed relative to reference conditions in an adjacent fen wetland that receives only natural runoff. Analysis of vegetation patterns at the quarry wetland site, using Detrended Correspondence Analysis and the species indicator values of Ellenberg, revealed a clear disparity between community transitions in the quarry wetland and the reference site. Limited establishment of moisture-sensitive taxa, the preferential proliferation of robust wetland species and an overall shift towards lower species diversity in the quarry wetland were explicable primarily by the physico-chemical environment created by quarry dewatering. This encompassed high pH (up to 12.8), sediment-rich effluent creating a nutrient-poor substrate with poor moisture retention in the quarry wetland, and large fluctuations in water levels. - High pH, sediment-rich runoff from a quarry constrains floristic diversity in an adjacent wetland

The impact of pumped water from a de-watered Magnesian limestone quarry on an adjacent wetland: Thrislington, County Durham, UK

Energy Technology Data Exchange (ETDEWEB)

Mayes, W.M. [Institute for Research on Environment and Sustainability, University of Newcastle, Newcastle upon Tyne NE1 7RU (United Kingdom)]. E-mail: w.m.mayes@ncl.ac.uk; Large, A.R.G. [School of Geography, Politics and Sociology, University of Newcastle, Newcastle upon Tyne NE1 7RU (United Kingdom); Younger, P.L. [Institute for Research on Environment and Sustainability, University of Newcastle, Newcastle upon Tyne NE1 7RU (United Kingdom)

2005-12-15

Although quarrying is often cited as a potential threat to wetland systems, there is a lack of relevant, quantitative case studies in the literature. The impact of pumped groundwater discharged from a quarry into a wetland area was assessed relative to reference conditions in an adjacent fen wetland that receives only natural runoff. Analysis of vegetation patterns at the quarry wetland site, using Detrended Correspondence Analysis and the species indicator values of Ellenberg, revealed a clear disparity between community transitions in the quarry wetland and the reference site. Limited establishment of moisture-sensitive taxa, the preferential proliferation of robust wetland species and an overall shift towards lower species diversity in the quarry wetland were explicable primarily by the physico-chemical environment created by quarry dewatering. This encompassed high pH (up to 12.8), sediment-rich effluent creating a nutrient-poor substrate with poor moisture retention in the quarry wetland, and large fluctuations in water levels. - High pH, sediment-rich runoff from a quarry constrains floristic diversity in an adjacent wetland.

WtF‐Nano: One‐Pot Dewatering and Water‐Free Topochemical Modification of Nanocellulose in Ionic Liquids or γ‐Valerolactone

Science.gov (United States)

Laaksonen, Tiina; Helminen, Jussi K. J.; Lemetti, Laura; Långbacka, Jesper; Rico del Cerro, Daniel; Hummel, Michael; Rantamäki, Antti H.; Kakko, Tia; Kemell, Marianna L.; Wiedmer, Susanne K.; Heikkinen, Sami; Kilpeläinen, Ilkka

2017-01-01

Abstract Ionic liquids are used to dewater a suspension of birch Kraft pulp cellulose nanofibrils (CNF) and as a medium for water‐free topochemical modification of the nanocellulose (a process denoted as “WtF‐Nano”). Acetylation was applied as a model reaction to investigate the degree of modification and scope of effective ionic liquid structures. Little difference in reactivity was observed when water was removed, after introduction of an ionic liquid or molecular co‐solvent. However, the viscoelastic properties of the CNF suspended in two ionic liquids show that the more basic, but non‐dissolving ionic liquid, allows for better solvation of the CNF. Vibrio fischeri bacterial tests show that all ionic liquids in this study were harmless. Scanning electron microscopy and wide‐angle X‐ray scattering on regenerated samples show that the acetylated CNF is still in a fibrillar form. 1 D and 2 D NMR analyses, after direct dissolution in a novel ionic liquid electrolyte solution, indicate that both cellulose and residual xylan on the surface of the nanofibrils reacts to give acetate esters. PMID:29112334

Observations of ebb flows on tidal flats: Evidence of dewatering?

Science.gov (United States)

Rinehimer, J. P.; Thomson, J. M.; Chickadel, C.

2010-12-01

Incised channels are a common morphological feature of tidal flats. When the flats are inundated, flows are generally forced by the tidally varying sea surface height. During low tide, however, these channels continue to drain throughout flat exposure even without an upstream source of water. While the role of porewater is generally overlooked due to the low permeability of marine muds, it remains the only potential source of flows through the channels during low tide. In situ and remotely sensed observations (Figure 1) at an incised channel on a tidal flat in Willapa Bay from Spring 2010 indicate that dewatering of the flats may be driving these low tide flows. High resolution Aquadopp ADCP velocity profiles are combined with observations from tower-based infrared (IR) video to produce a complete time series of surface velocity measurements throughout low tide. The IR video observations provide a measurement of surface currents even when the channel depth is below the blanking distance of the ADCP (10 cm). As the depth within the channel drops from 50 cm to 10 cm surface velocities increase from 10 cm/s to 60 cm/s even as the tide level drops below the channel flanks and the flats are dry. As the drainage continues, the temperature of the flow rises throughout low tide, mirroring temperatures within the sediment bed on the tidal flat. Drainage salinity falls despite the lack of any freshwater input to the flat indicating that less saline porewater may be the source. The likely source of the drainage water is from the channel flanks where time-lapse video shows slumping and compaction of channel sediments. Velocity profiles, in situ temperatures, and IR observations also are consistent with the presence of fluid muds and a hyperpycnal, density driven outflow at the channel mouth highlighting a possible pathway for sediment delivery from the flats to the main distributary channels of the bay. Figure 1: Time series of tidal flat channel velocities and temperatures

Engineering properties of nuclear waste slurries - 16378

International Nuclear Information System (INIS)

Biggs, Simon; Fairweather, Michael; Hunter, Timothy; Omokanye, Qanitalillahi; Peakall, Jeffrey

2009-01-01

The type of particulate systems encountered in legacy nuclear waste slurries is highly complicated, with the aggregation and flow behaviour being at times very variable. However, deconstructing the complex overall slurry activity to singular particle-particle interactions can lead to a greater understanding of the mechanisms involved with particle aggregation, and so to predictions of their settling and flow in nuclear systems. Of particular importance to legacy waste is the role of salts in controlling the attraction of particles (and so in dictating the rheological properties of the system) as sludge may contain a variety of specific ions and generally have high ionic conductivity [1]. In this paper, particle-particle interactions are characterised using a number of complimentary methods, and their influence on resulting flow and bed compression is measured. The methods used to characterise the particle-particle interactions under various salt and pH conditions were electro-acoustic analysis (zeta potential) and atomic force microscopy (AFM). Following on from the analysis of particle-particle properties, bulk sediment behaviour was investigated using shear and compressive yield stress measurements, vital parameters in dictating flow and dewatering performance, respectively. Together, these techniques enable the characterisation of a range of particulate systems that may be encountered in legacy wastes, and results point to a number of important factors that can help explain the observed variability in industrial slurry behaviour. (authors)

Nitrogen dynamics model for a pilot field-scale novel dewatered alum sludge cake-based constructed wetland system.

Science.gov (United States)

Kumar, J L G; Zhao, Y Q; Hu, Y S; Babatunde, A O; Zhao, X H

2015-01-01

A model simulating the effluent nitrogen (N) concentration of treated animal farm wastewater in a pilot on-site constructed wetland (CW) system, using dewatered alum sludge cake (DASC) as wetland substrate, is presented. The N-model was developed based on the Structural Thinking Experiential Learning Laboratory with Animation software and is considering organic nitrogen, ammonia nitrogen (NH3) and nitrate nitrogen (NO3-N) as the major forms of nitrogen involved in the transformation chains. Ammonification (AMM), ammonia volatilization, nitrification (NIT), denitrification, plant uptake, plant decaying and uptake of inorganic nitrogen by algae and bacteria were considered in this model. pH, dissolved oxygen, temperature, precipitation, solar radiation and nitrogen concentrations were considered as forcing functions in the model. The model was calibrated by observed data with a reasonable agreement prior to its applications. The simulated effluent detritus nitrogen, NH4-N, NO3-N and TN had a considerably good agreement with the observed results. The mass balance analysis shows that NIT accounts for 65.60%, adsorption (ad) (11.90%), AMM (8.90%) followed by NH4-N (Plants) (5.90%) and NO3-N (Plants) (4.40%). The TN removal was found 52% of the total influent TN in the CW. This study suggested an improved overall performance of a DASC-based CW and efficient N removal from wastewater.

Paradoxical Effects of Sodium-Calcium Exchanger Inhibition on Torsade de Pointes and Early Afterdepolarization in a Heart Failure Rabbit Model.

Science.gov (United States)

Chang, Po-Cheng; Lu, Yu-Ying; Lee, Hui-Ling; Lin, Shien-Fong; Chu, Yen; Wen, Ming-Shien; Chou, Chung-Chuan

2018-05-03

Calcium homeostasis plays an important role in development of early afterdepolarizations (EADs) and torsade de pointes (TdP). The role of sodium-calcium exchanger (NCX) inhibition in genesis secondary Ca rise and EADs-TdP is still debated. Dual voltage and intracellular Ca optical mapping were conducted in 6 control and 9 failing rabbit hearts. After baseline electrophysiological and optical mapping studies, E4031 was given to simulate long QT syndrome. ORM-10103 was then administrated to examine the electrophysiological effects on EAD-TdP development. E4031 enhanced secondary Ca rise, EADs development and TdP inducibility in both control and failing hearts. The results showed that ORM-10103 reduced premature ventricular beats (PVBs) but was unable to suppress the inducibility of TdP or EADs. The electrophysiological effects of ORM-10103 included prolongation of action potential duration (APD) and increased APD heterogeneity in failing hearts. ORM10103 had a neutral effect on the amplitude of secondary Cai rise in control and HF groups. In this model, most EADs generated from the long-short APD junction area. In conclusion, highly selective NCX inhibition with ORM-10103 reduced PVB burden but was unable to suppress secondary Ca rise, EADs development nor inducibility of TdP. The possible electrophysiological mechanisms include APD prolongation and increased APD heterogeneity.

Over-the-Counter Hearing Aids: A Lost Decade for Change

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Zoe Yee Ting Chan

2015-01-01

Full Text Available Background. Hearing aids sold directly to consumers in retail stores or through the internet, without individual prescription by audiological professionals, are termed over-the-counter (OTC devices. This study aimed to determine whether there was any change in the electroacoustic characteristics of OTC devices compared to research carried out a decade earlier. The previous results indicated that most OTC devices were low-frequency-emphasis devices and were unsuitable for elderly people with presbycusis, who were likely to be the major consumers of these products. Methods. Ten OTC devices were selected and their electroacoustic performance was measured. Appropriate clients for the OTC devices were derived, using four linear prescription formulae, and OTC suitability for elderly persons with presbycusis was investigated. Results. OTC electroacoustic characteristics were similar to those in the earlier study. Most OTC devices were not acoustically appropriate for potential consumers with presbycusis. Although several of the devices could match prescriptive targets for individuals with presbycusis, their poor electroacoustic performance—including ineffective volume control function, high equivalent input noise, and irregular frequency response—may override their potential benefit. Conclusion. The low-cost OTC devices were generally not suitable for the main consumers of these products, and there has been little improvement in the appropriateness of these devices over the past decade.

Over-the-Counter Hearing Aids: A Lost Decade for Change

Science.gov (United States)

Chan, Zoe Yee Ting; McPherson, Bradley

2015-01-01

Background. Hearing aids sold directly to consumers in retail stores or through the internet, without individual prescription by audiological professionals, are termed over-the-counter (OTC) devices. This study aimed to determine whether there was any change in the electroacoustic characteristics of OTC devices compared to research carried out a decade earlier. The previous results indicated that most OTC devices were low-frequency-emphasis devices and were unsuitable for elderly people with presbycusis, who were likely to be the major consumers of these products. Methods. Ten OTC devices were selected and their electroacoustic performance was measured. Appropriate clients for the OTC devices were derived, using four linear prescription formulae, and OTC suitability for elderly persons with presbycusis was investigated. Results. OTC electroacoustic characteristics were similar to those in the earlier study. Most OTC devices were not acoustically appropriate for potential consumers with presbycusis. Although several of the devices could match prescriptive targets for individuals with presbycusis, their poor electroacoustic performance—including ineffective volume control function, high equivalent input noise, and irregular frequency response—may override their potential benefit. Conclusion. The low-cost OTC devices were generally not suitable for the main consumers of these products, and there has been little improvement in the appropriateness of these devices over the past decade. PMID:26557701

Early Allograft Dysfunction Is Associated With Higher Risk of Renal Nonrecovery After Liver Transplantation

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Hani M. Wadei, MD

2018-04-01

Full Text Available Abstract. Early allograft dysfunction (EAD identifies allografts with marginal function soon after liver transplantation (LT and is associated with poor LT outcomes. The impact of EAD on post-LT renal recovery, however, has not been studied. Data on 69 primary LT recipients (41 with and 28 without history of renal dysfunction who received renal replacement therapy (RRT for a median (range of 9 (13-41 days before LT were retrospectively analyzed. Primary outcome was renal nonrecovery defined as RRT requirement 30 days from LT. Early allograft dysfunction developed in 21 (30% patients, and 22 (32% patients did not recover renal function. Early allograft dysfunction was more common in the renal nonrecovery group (50% vs 21%, P = 0.016. Multivariate logistic regression analysis demonstrated that EAD (odds ratio, 7.25; 95% confidence interval, 2.0-25.8; P = 0.002 and baseline serum creatinine (odds ratio, 3.37; 95% confidence interval, 1.4-8.1; P = 0.007 were independently associated with renal nonrecovery. History of renal dysfunction, duration of renal dysfunction, and duration of RRT were not related to renal recovery (P > 0.2 for all. Patients who had EAD and renal nonrecovery had the worst 1-, 3-, and 5-year patient survival, whereas those without EAD and recovered renal function had the best outcomes (P < 0.001. Post-LT EAD was independently associated with renal nonrecovery in LT recipients on RRT for a short duration before LT. Furthermore, EAD in the setting of renal nonrecovery resulted in the worst long-term survival. Measures to prevent EAD should be undertaken in LT recipients on RRT at time of LT.

A busca da qualidade na educação superior a distância no Brasil situação atual e algumas reflexões

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Marlene M. Blois

2004-06-01

Full Text Available Panorama da Educação no Brasil, com destaque para a Educação Superior. Número de alunos matriculados e formação dos docentes no ensino superior. Causas do crescimento da Educação a Distância no país e instituições de Educação Superior credenciadas para ofertas de EAD. Definição para a EAD. A Regulamentação e os Referenciais de Qualidade para a EAD. A legislação em vigor no país. A avaliação de programas e cursos de EAD. Diplomas de cursos realizados em instituições estrangeiras. Os critérios de qualidade recomendados pelo Ministério da Educação para a EAD. Pontos para reflexão sobre os temas abordados.

Reply to Comment by Xu et al. on "Sr-Nd isotope composition and clay mineral assemblages in eolian dust from the central Philippine Sea over the last 600 kyr: Implications for the transport mechanism of Asian dust" by Seo et al.

Science.gov (United States)

Seo, Inah; Lee, Yong Il; Yoo, Chan Min; Kim, Hyung Jeek; Hyeong, Kiseong

2016-12-01

Against Xu et al. (2016), who argued that East Asian Desert (EAD) dust that traveled on East Asian Winter Monsoon winds dominates over Central Asian Desert (CAD) dust in the Philippine Sea with presentation of additional data, we reconfirm Seo et al.'s (2014) conclusion that CAD dust carried on the Prevailing Westerlies and Trade Winds dominates over EAD dust in overall dust budget of the central Philippine Sea. The relative contribution of dust from EADs and CADs using clay mineral composition should be evaluated with elimination of mineralogical contribution from the volcanic end-member which is enriched in kaolinite and overestimate the contribution of EAD dust.

Psychometric characteristics of the Eating and Appraisal Due to Emotions and Stress Questionnaire and obesity in Mexican university students.

Science.gov (United States)

Lazarevich, Irina; Irigoyen-Camacho, María Esther; Velazquez-Alva, María del Consuelo; Salinas-Ávila, Jaqueline

2015-06-01

Emotional eating has been defined as eating in a response to negative emotions and it is associated with weight gain. The English version of Eating Appraisal Due to Emotions and Stress Questionnaire (EADES) was developed to assess how individuals use food in order to cope with stress and emotions. To analyze psychometric characteristics of Spanish version of EADES and to identify whether the constructs of EADES were associated with obesity in university students. The EADES (Spanish version) was administered to 232 Mexican university students from 18 to 29 years old. Body Mass Index (BMI) was calculated. A test-retest evaluation was conducted with 75 participants. Cronbach's alpha of EADES was 0.92; the interclass correlation coefficient was 0.88. Regarding BMI and EADES results, the subscale Emotion and Stress Related Eating was significantly associated with obesity (p = 0.026). Through factor analysis of the instrument, three factors were extracted and items that showed factor loading obesity and the 40-items version of the instrument, a statistically significance association was found for the total score (OR = 0.973, p = 0.020) and for the factor Self-confidence related to Emotional Eating component (OR = 0.940, p = 0.026). A good internal consistency and temporal stability of the Spanish version of the instrument were found; the 40-item EADES version was positively associated with obesity. This instrument could be useful in assessing emotional eating. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Perception and musical preferences in Wishart's work

DEFF Research Database (Denmark)

Brattico, E; Sassanelli, F

2000-01-01

This paper has its origin from the analysis of the works of Trevor Wishart, one of the most representative composers of the English electroacoustic tradition, who has been orienting his research to study the possibilities of electroacoustics applied to human voice. Quoting Schaeffer, ill his book...... to human language differently manipulated,Wishart gives his personal interpretation of the problem. His solution and how it is coherent with the last theories and findings of cognitive sciences are here examined....

A Comparative Study of Early Afterdepolarization-Mediated Fibrillation in Two Mathematical Models for Human Ventricular Cells.

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Soling Zimik

Full Text Available Early afterdepolarizations (EADs, which are abnormal oscillations of the membrane potential at the plateau phase of an action potential, are implicated in the development of cardiac arrhythmias like Torsade de Pointes. We carry out extensive numerical simulations of the TP06 and ORd mathematical models for human ventricular cells with EADs. We investigate the different regimes in both these models, namely, the parameter regimes where they exhibit (1 a normal action potential (AP with no EADs, (2 an AP with EADs, and (3 an AP with EADs that does not go back to the resting potential. We also study the dependence of EADs on the rate of at which we pace a cell, with the specific goal of elucidating EADs that are induced by slow or fast rate pacing. In our simulations in two- and three-dimensional domains, in the presence of EADs, we find the following wave types: (A waves driven by the fast sodium current and the L-type calcium current (Na-Ca-mediated waves; (B waves driven only by the L-type calcium current (Ca-mediated waves; (C phase waves, which are pseudo-travelling waves. Furthermore, we compare the wave patterns of the various wave-types (Na-Ca-mediated, Ca-mediated, and phase waves in both these models. We find that the two models produce qualitatively similar results in terms of exhibiting Na-Ca-mediated wave patterns that are more chaotic than those for the Ca-mediated and phase waves. However, there are quantitative differences in the wave patterns of each wave type. The Na-Ca-mediated waves in the ORd model show short-lived spirals but the TP06 model does not. The TP06 model supports more Ca-mediated spirals than those in the ORd model, and the TP06 model exhibits more phase-wave patterns than does the ORd model.

A Comparative Study of Early Afterdepolarization-Mediated Fibrillation in Two Mathematical Models for Human Ventricular Cells

Science.gov (United States)

Zimik, Soling; Vandersickel, Nele; Nayak, Alok Ranjan; Panfilov, Alexander V.; Pandit, Rahul

2015-01-01

Early afterdepolarizations (EADs), which are abnormal oscillations of the membrane potential at the plateau phase of an action potential, are implicated in the development of cardiac arrhythmias like Torsade de Pointes. We carry out extensive numerical simulations of the TP06 and ORd mathematical models for human ventricular cells with EADs. We investigate the different regimes in both these models, namely, the parameter regimes where they exhibit (1) a normal action potential (AP) with no EADs, (2) an AP with EADs, and (3) an AP with EADs that does not go back to the resting potential. We also study the dependence of EADs on the rate of at which we pace a cell, with the specific goal of elucidating EADs that are induced by slow or fast rate pacing. In our simulations in two- and three-dimensional domains, in the presence of EADs, we find the following wave types: (A) waves driven by the fast sodium current and the L-type calcium current (Na-Ca-mediated waves); (B) waves driven only by the L-type calcium current (Ca-mediated waves); (C) phase waves, which are pseudo-travelling waves. Furthermore, we compare the wave patterns of the various wave-types (Na-Ca-mediated, Ca-mediated, and phase waves) in both these models. We find that the two models produce qualitatively similar results in terms of exhibiting Na-Ca-mediated wave patterns that are more chaotic than those for the Ca-mediated and phase waves. However, there are quantitative differences in the wave patterns of each wave type. The Na-Ca-mediated waves in the ORd model show short-lived spirals but the TP06 model does not. The TP06 model supports more Ca-mediated spirals than those in the ORd model, and the TP06 model exhibits more phase-wave patterns than does the ORd model. PMID:26125185

The disc method. A new method for selecting facilitations in flocculating sludge to be dewatered in centrifuges; Metodo de disco. Un nuevo metodo para la seleccion de floculantes en la floculacion de lodos a deshidratar en centrifugas

Energy Technology Data Exchange (ETDEWEB)

Canga Rodriguez, J.; Gutierrez Lavin, A.

2002-07-01

An experimental protocol was designed at a laboratory scale, in view of achieving the selection with different poly electrolytes related to the chemical conditioning (flocculation) of sewage sludge before dewatering it in a drying centrifuge. The method is based on a new parameter of quality of the formed floc, which measures its compaction when is submitted to a fix external strength. Some experimental tests have been introduced, whose results are numbers, avoiding all subjective aspects related to direct observation of flocs. (Author) 8 refs.

A interatividade na educação a distância: avanços e desafios

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Edna Cristina do Prado

2008-01-01

Full Text Available Demand is discussed in this article the importance of interactivity in the education process provided in the form of Distance at Education (EAD, above, bringing aspects related to theories of learning and the challenges that still have to consolidate the EAD. These challenges can be pointing the prejudice existing in relation to EAD and the need for preparation of a project of course guided in a new design on the teaching and learning process. The construction of a new educational paradigm that can enable the democratization of education requires an effort that more conceptual, requires urgent, the construction of a network of social learning and research that can strengthen the growth and recovery of EAD.

Regional difference of glucose metabolism reduction in equivocal Alzheimer's disease and elderly depressed patients

International Nuclear Information System (INIS)

Cho, S. S.; Kang, E. J.; Lee, J. S.; Lee, D. S.; Lee, K. U.; Chung, J. K.; Woo, J. I.; Lee, M. C.

2001-01-01

The aim of this study was to investigate the difference in cerebral glucose metabolism between patients with equivocal Alzheimer's disease (eAD) and those with elderly major depression (DEP). 31 patients with eAD, 7 patients with DEP, and 15 age matched normal controls were scanned with FDG-PET. Each FDG-PET images was normalized to the cerebellar activity before voxel-voxel analysis using SPM99. In comparison with normal controls, the eAD patents showed the most significant reduction of glucose metabolism (hypometabolism) in anterior inferior temporal gyrus in left, followed by bilateral posterior cingulate, left thalamus, and inferior parietal lobe. Patients with DEP showed hypometabolism in precuneus, inferior and middle frontal gyri in left, and right angular gyrus. Significantly lower activity was found in left inferior temporal gyrus in DEP in comparison to the eAD. Patients with eAD and DEP showed different pattern of hypometabolism, especially in inferior temporal gyrus. FDG brain PET may be useful in differential diagnosis between equivocal Alzheimer's disease and elderly depression

Nuevas formas de aprendizaje en EAD / New learning methods on EAD

Directory of Open Access Journals (Sweden)

Beatriz Elena García Londoño

2007-01-01

Full Text Available El trabajo tiene como propósito analizar las nuevas formas de aprendizaje en educación a distancia desde la teoría de la metacognición o el metaaprendizaje, el mismo se entiende como el proceso de estructuración y transformación que el sujeto hace de la información y no como simple asimilación de la misma. Para lograr lo anterior, las formas de comunicación y las mediaciones didácticas, utilizadas en la educación a distancia, así como la comunicación, los materiales impresos y no impresos y la acción tutorial han de interactuar e interrelacionarse con las características de la persona que aprende y con sus esquemas previos de conocimiento y configurar un proceso de aprendizaje complejo, sistemático y organizado más allá de simples asociaciones memorísticas, en el cual el estudiante pueda interactuar con su entorno; darle sentido al mundo que percibe; procesar activamente información y generar conocimiento; crear vínculos y relaciones entre el conocimiento que posee y lo que está tratando de aprender; usar las palabras, los símbolos y los significados para la comprensión de los conceptos y como punto de lanza para construir un aprendizaje proposicional y generar nuevos significados. Lo anterior demanda el desarrollo de capacidades autónomas y permanentes de aprender a aprender, fundamento de la metacognición o el metaaprendizaje. This paper deals with analyzing new ways of apprenticeship in distance education within the theories of metacognition and metapprenticeship; it is understood as the structuralization and transformation which subject fulfils out of information rather than the simple assimilation of it. To achieve this, the communicative forms and the didactic mediations, made use of in distance education, as well as Communication itself, printed and unprinted material and tutorial action, are to interact and interrelate to the apprentice characteristics and to his/her previous cognitive schemes in order to shape a complex, systematic and organized apprenticeship process, beyond the simple memoirist associations. The process will make a pupil be able to interact within his/her environment, to give sense to the world perceived, to process information actively and to generate knowledge. As well as creating links and relations between achieved knowledge and that likely to learn; using words, symbols and meanings for the conceptual comprehension necessary to the building of propositional learning and to the construction of new signified. The former demands the development of autonomous and permanent capacities related to the learn-to-learn processes: fundamental to the metacognition ant the metapprenticeship. Within the preceding perspective, the article looks for developing the following: in distance education, rather than transmitting knowledge, learn-to-learn competences have to be constructed. The former may be grounded through the intensive use made by the contemporary societies out of the mediated on-line knowledge, which allows transmitting almost infinite volumes of information and to reduce time and space using communicative and informative technologies. It may be also grounded through the conception of educational systems which more often devote less to transmit knowledge from an uniform curriculum and find their way to lead students into the learn-to-learn path within non-school environments such us radio, phone, television or fax mediated issues, as well as television and movie images, newspapers words and icons, publicity advertising and books, and virtual, interactive and multimedia environments.

Spatial Patterns of Excitation at Tissue and Whole Organ Level Due to Early Afterdepolarizations

Directory of Open Access Journals (Sweden)

Nele Vandersickel

2017-06-01

Full Text Available Early after depolarizations (EAD occur in many pathological conditions, such as congenital or acquired channelopathies, drug induced arrhythmias, and several other situations that are associated with increased arrhythmogenicity. In this paper we present an overview of the relevant computational studies on spatial EAD dynamics in 1D, 2D, and in 3D anatomical models and discuss the relation of EADs to cardiac arrhythmias. We also discuss unsolved problems and highlight new lines of research in this area.

Morphological correlates of hearing loss after cochlear implantation and electro-acoustic stimulation in a hearing-impaired Guinea pig model.

Science.gov (United States)

Reiss, Lina A J; Stark, Gemaine; Nguyen-Huynh, Anh T; Spear, Kayce A; Zhang, Hongzheng; Tanaka, Chiemi; Li, Hongzhe

2015-09-01

Hybrid or electro-acoustic stimulation (EAS) cochlear implants (CIs) are designed to provide high-frequency electric hearing together with residual low-frequency acoustic hearing. However, 30-50% of EAS CI recipients lose residual hearing after implantation. The objective of this study was to determine the mechanisms of EAS-induced hearing loss in an animal model with high-frequency hearing loss. Guinea pigs were exposed to 24 h of noise (12-24 kHz at 116 dB) to induce a high-frequency hearing loss. After recovery, two groups of animals were implanted (n = 6 per group), with one group receiving chronic acoustic and electric stimulation for 10 weeks, and the other group receiving no stimulation during this time frame. A third group (n = 6) was not implanted, but received chronic acoustic stimulation. Auditory brainstem responses were recorded biweekly to monitor changes in hearing. The organ of Corti was immunolabeled with phalloidin, anti-CtBP2, and anti-GluR2 to quantify hair cells, ribbons and post-synaptic receptors. The lateral wall was immunolabeled with phalloidin and lectin to quantify stria vascularis capillary diameters. Bimodal or trimodal diameter distributions were observed; the number and location of peaks were objectively determined using the Aikake Information Criterion and Expectation Maximization algorithm. Noise exposure led to immediate hearing loss at 16-32 kHz for all groups. Cochlear implantation led to additional hearing loss at 4-8 kHz; this hearing loss was negatively and positively correlated with minimum and maximum peaks of the bimodal or trimodal distributions of stria vascularis capillary diameters, respectively. After chronic stimulation, no significant group changes in thresholds were seen; however, elevated thresholds at 1 kHz in implanted, stimulated animals were significantly correlated with decreased presynaptic ribbon and postsynaptic receptor counts. Inner and outer hair cell counts did not differ between groups and

Talumatud tülid ettevõtte sees katkestasid Airbusi järsu tõusu / Peggy Hollinger, Gerrit Wiesmann ; tõlk. Erik Aru

Index Scriptorium Estoniae

Hollinger, Peggy

2006-01-01

Euroopa lennu- ja kosmosetööstus EADS pidi suutma Airbusi efektiivselt juhtida, kuid ei suutnud Airbusis lepitada vastakaid huve. Konfliktidest EADS-i juhtide hulgas, probleemidest A 380 valmimisel. Lisa: Airbus ei looda ainult A380-le

Theoretical Study on Nano-Catalyst Burn Rate

Science.gov (United States)

2014-11-26

the adsorbed system EAP +surface and the adsorption state, with a positive value of Eads being thermodynamically favorable: Eads = (Esurface + EAP ... EAP +surface, (1) The interaction between the TiO2 surfaces and the AP molecules has been analyzed by

Comparing Methods of Calculating Expected Annual Damage in Urban Pluvial Flood Risk Assessments

Directory of Open Access Journals (Sweden)

Anders Skovgård Olsen

2015-01-01

Full Text Available Estimating the expected annual damage (EAD due to flooding in an urban area is of great interest for urban water managers and other stakeholders. It is a strong indicator for a given area showing how vulnerable it is to flood risk and how much can be gained by implementing e.g., climate change adaptation measures. This study identifies and compares three different methods for estimating the EAD based on unit costs of flooding of urban assets. One of these methods was used in previous studies and calculates the EAD based on a few extreme events by assuming a log-linear relationship between cost of an event and the corresponding return period. This method is compared to methods that are either more complicated or require more calculations. The choice of method by which the EAD is calculated appears to be of minor importance. At all three case study areas it seems more important that there is a shift in the damage costs as a function of the return period. The shift occurs approximately at the 10 year return period and can perhaps be related to the design criteria for sewer systems. Further, it was tested if the EAD estimation could be simplified by assuming a single unit cost per flooded area. The results indicate that within each catchment this may be a feasible approach. However the unit costs varies substantially between different case study areas. Hence it is not feasible to develop unit costs that can be used to calculate EAD, most likely because the urban landscape is too heterogeneous.

29 CFR 4041.45 - Distress termination notice.

Science.gov (United States)

2010-07-01

..., Single-Employer Plan Termination, with Schedule EA-D, Distress Termination Enrolled Actuary Certification... guaranteed benefits. Unless the enrolled actuary certifies, in the Schedule EA-D filed in accordance with... benefits or benefit liabilities. If the enrolled actuary certifies that the plan is sufficient either for...

Mutations of amino acids in the DNA-recognition domain of Epstein-Barr virus ZEBRA protein alter its sub-nuclear localization and affect formation of replication compartments

International Nuclear Information System (INIS)

Park, Richard; Heston, Lee; Shedd, Duane; Delecluse, Henri-Jacques; Miller, George

2008-01-01

ZEBRA, a transcription factor and DNA replication protein encoded by the Epstein-Barr virus (EBV) BZLF1 gene, plays indispensable roles in the EBV lytic cycle. We recently described the phenotypes of 46 single amino acid substitutions introduced into the DNA-recognition region of ZEBRA [Heston, L., El-Guindy, A., Countryman, J., Dela Cruz, C., Delecluse, H.J., and Miller, G. 2006]. The 27 DNA-binding-proficient mutants exhibited distinct defects in their ability to activate expression of the kinetic classes of viral genes. Four phenotypic variants could be discerned: wild-type, defective at activating Rta, defective at activating early genes, and defective at activating late genes. Here we analyze the distribution of ZEBRA within the nucleus and the localization of EA-D (the viral DNA polymerase processivity factor), an indicator of the development of replication compartments, in representatives of each phenotypic group. Plasmids encoding wild-type (WT) and mutant ZEBRA were transfected into 293 cells containing EBV-bacmids. WT ZEBRA protein was diffusely and smoothly distributed throughout the nucleus, sparing nucleoli, and partially recruited to globular replication compartments. EA-D induced by WT ZEBRA was present diffusely in some cells and concentrated in globular replication compartments in other cells. The distribution of ZEBRA and EA-D proteins was identical to WT following transfection of K188R, a mutant with a conservative change. The distribution of S186A mutant ZEBRA protein, defective for activation of Rta and EA-D, was identical to WT, except that the mutant ZEBRA was never found in globular compartments. Co-expression of Rta with S186A mutant rescued diffuse EA-D but not globular replication compartments. The most striking observation was that several mutant ZEBRA proteins defective in activating EA-D (R179A, K181A and A185V) and defective in activating lytic viral DNA replication and late genes (Y180E and K188A) were localized to numerous punctate

Unified Modeling of Filtration and Expression of Biological Sludge

DEFF Research Database (Denmark)

Sørensen, Peter Borgen

Dewatering is a costly operation in both industry, e.g . when dewatering drilling mud, harbor sludge or biomass, and at municipal wastewater treatment plants when dewatering biological sludges. In practice, design and operation of dewatering equipment are mostly based on empirical knowledge, and ......, and normally results are not satisfactory, e.g. in terms of cake solids or capacity of equipment. Thus, there is a need for theoretical and technical developments to improve dewatering performance, based on better scientific knowledge and well defined principles and rules....

Gestão Estratégica de Sistemas de Educação a Distância no Brasil e em Portugal: a propósito da flexibilidade educacional

Directory of Open Access Journals (Sweden)

Daniel Mill

2015-06-01

Full Text Available RESUMO:O texto apresenta reflexões sobre os princípios da flexibilidade educacional e sua repercussão na qualidade de propostas de ensino-aprendizagem da Educação a Distância (EaD. No trabalho, o Grupo Horizonte analisa o espaço , o tempo e a organização curricular como elementos fundantes da flexibilidade. Sendo qualiquantitativa, a pesquisa usou entrevistas semiestruturadas e questionários virtuais na coleta de dados. Estruturou-se uma matriz comparativa das experiências de EaD portuguesas e brasileiras para buscar estratégias de flexibilidade pedagógica bem-sucedidas em modelos lusos que enriquecessem a EaD brasileira. Observamos que experiências de EaD portuguesas e brasileiras ainda buscam maior maleabilidade pedagógica. Anseiam por mais conhecimentos sobre a flexibilidade pedagógica: onde (espaço, quando (tempo e como (organização curricular ocorre o ensino-aprendizagem na cibercultura.

Comparing Methods of Calculating Expected Annual Damage in Urban Pluvial Flood Risk Assessments

DEFF Research Database (Denmark)

Skovgård Olsen, Anders; Zhou, Qianqian; Linde, Jens Jørgen

2015-01-01

Estimating the expected annual damage (EAD) due to flooding in an urban area is of great interest for urban water managers and other stakeholders. It is a strong indicator for a given area showing how vulnerable it is to flood risk and how much can be gained by implementing e.g., climate change...... adaptation measures. This study identifies and compares three different methods for estimating the EAD based on unit costs of flooding of urban assets. One of these methods was used in previous studies and calculates the EAD based on a few extreme events by assuming a log-linear relationship between cost...... of an event and the corresponding return period. This method is compared to methods that are either more complicated or require more calculations. The choice of method by which the EAD is calculated appears to be of minor importance. At all three case study areas it seems more important that there is a shift...

Assessing damage cost estimation of urban pluvial flood risk as a mean of improving climate change adaptations investments

DEFF Research Database (Denmark)

Skovgård Olsen, Anders; Zhou, Qianqian; Linde, Jens Jørgen

Estimating the expected annual damage (EAD) due to flooding in an urban area is of great interest for urban water managers and other stakeholders. It is a strong indicator for a given area showing how it will be affected by climate change and how much can be gained by implementing adaptation...... measures. This study investigates three different methods for estimating the EAD based on a loglinear relation between the damage costs and the return periods, one of which has been used in previous studies. The results show with the increased amount of data points there appears to be a shift in the log......-linear relation which could be contributed by the Danish design standards for drainage systems. Three different methods for estimating the EAD were tested and the choice of method is less important than accounting for the log-linear shift. This then also means that the statistical approximation of the EAD used...

CRESCIMENTO DA EDUCAÇÃO A DISTÂNCIA E SEUS DESAFIOS: UMA REVISÃO BIBLIOGRÁFICA

OpenAIRE

Thyanne Michelle Ferreira Alves; Afonso Henrique Novaes Menezes; Flávia Maria de Brito Pedrosa Vasconcelo

2015-01-01

Este estudo propôs como tema a Educação a Distância (EaD) como modalidade de ensino que está em constante crescimento na contemporaneidade. O intuito desta pesquisa bibliográfica está em apresentar as características da EaD e os desafios a serem superados na formação de indivíduos que almejam uma educação de qualidade. Os fatores influentes para o desenvolvimento da EaD estão caracterizados na metodologia e mídias utilizadas pelos educadores durante o processo pedagógico. Para a eficácia na r...

III Colóquio luso-brasileiro de educação a distância e elearning

OpenAIRE

Amante, Lúcia; Mendes, António Quintas; Barros, Daniela Melaré Vieira; Cardoso, Teresa; Spilker, Maria João

2013-01-01

O livro de atas do III Colóquio Luso-Brasileiro de Educação a Distância e Elearning, realizado em Lisboa em dezembro de 2013, reúne um vasto conjunto de comunicações apresentadas no evento e que se distribuem por 10 grandes temas a saber: EaD e Políticas educativas; Boas Práticas em Educação Online; Modelos e Processos Pedagógicos em Educação online; Web 2.0 e tecnologias emergentes; Pedagogias emergentes (PLEs, MOOCs, REAs, …); Realidade Virtual em EaD; Jogos e gamification em EaD; Mobile Le...

The Semantic Mapping of Archival Metadata to the CIDOC CRM Ontology

Science.gov (United States)

Bountouri, Lina; Gergatsoulis, Manolis

2011-01-01

In this article we analyze the main semantics of archival description, expressed through Encoded Archival Description (EAD). Our main target is to map the semantics of EAD to the CIDOC Conceptual Reference Model (CIDOC CRM) ontology as part of a wider integration architecture of cultural heritage metadata. Through this analysis, it is concluded…

A score model for the continuous grading of early allograft dysfunction severity.

Science.gov (United States)

Pareja, Eugenia; Cortes, Miriam; Hervás, David; Mir, José; Valdivieso, Andrés; Castell, José V; Lahoz, Agustín

2015-01-01

Early allograft dysfunction (EAD) dramatically influences graft and patient outcomes. A lack of consensus on an EAD definition hinders comparisons of liver transplant outcomes and management of recipients among and within centers. We sought to develop a model for the quantitative assessment of early allograft function [Model for Early Allograft Function Scoring (MEAF)] after transplantation. A retrospective study including 1026 consecutive liver transplants was performed for MEAF score development. Multivariate data analysis was used to select a small number of postoperative variables that adequately describe EAD. Then, the distribution of these variables was mathematically modeled to assign a score for each actual variable value. A model, based on easily obtainable clinical parameters (ie, alanine aminotransferase, international normalized ratio, and bilirubin) and scoring liver function from 0 to 10, was built. The MEAF score showed a significant association with patient and graft survival at 3-, 6- and 12-month follow-ups. Hepatic steatosis and age for donors; cold/warm ischemia times and postreperfusion syndrome for surgery; and intensive care unit and hospital stays, Model for End-Stage Liver Disease and Child-Pugh scores, body mass index, and fresh frozen plasma transfusions for recipients were factors associated significantly with EAD. The model was satisfactorily validated by its application to an independent set of 200 patients who underwent liver transplantation at a different center. In conclusion, a model for the quantitative assessment of EAD severity has been developed and validated for the first time. The MEAF provides a more accurate graft function assessment than current categorical classifications and may help clinicians to make early enough decisions on retransplantation benefits. Furthermore, the MEAF score is a predictor of recipient and graft survival. The standardization of the criteria used to define EAD may allow reliable comparisons of

Adding Archival Finding Aids to the Library Catalogue: Simple Crosswalk or Data Traffic Jam?

Directory of Open Access Journals (Sweden)

Geoff Brown

2007-03-01

Full Text Available Dalhousie University Archives and Special Collections (DUASC has been producing Encoded Archival Description (EAD finding aids to describe its archival collections since 2003. The EAD descriptions started as a way to convert the collection of print and electronic (Microsoft Word and WordPerfect finding aids into a stable, software neutral format. As the collection of finding aids grew, it became apparent that we needed a way to search these documents beyond what was possible via a basic browse on the DUASC website. As a result, we embarked on a systematic crosswalk of the EAD finding aids into MARC 21 format for inclusion in the Novanet library catalogue. This has facilitated searching and discovery of the materials by a much broader audience of Dalhousie University Library users as well as users from all of the other Novanet member libraries in Nova Scotia and the general public. This article describes the primary motivation for the project and the technical aspects of converting the EAD finding aids into MARC 21 format for inclusion in the Novanet catalogue.

On Elementary Affective Decisions: To Like Or Not To Like, That Is The Question

Directory of Open Access Journals (Sweden)

Art M Jacobs

2016-11-01

Full Text Available Perhaps the most ubiquitous and basic affective decision of daily life is deciding whether we like or dislike something/somebody, or, in terms of psychological emotion theories, whether the object/subject has positive or negative valence. Indeed, people constantly make such liking decisions within a glimpse and, importantly, sometimesoften without expecting any obvious benefit or knowing the exact reasons for their judgment. In this paper, we review research on such elementary affective decisions (EADs that entail no direct overt reward with a special focus on Neurocognitive Poetics and discuss methods and models for investigating the neuronal and cognitive-affective bases of EADs to verbal materials with differing degrees of complexity. In line with evolutionary and appraisal theories of (aesthetic emotions and data from recent neurocognitive studies, the results of a decision-tree modeling approach simulating EADs to single words suggest that a main driving force behind EADs is the extent to which such high-dimensional stimuli are associated with the basic emotions joy/happiness and disgust.

Adding Archival Finding Aids to the Library Catalogue: Simple Crosswalk or Data Traffic Jam?

Directory of Open Access Journals (Sweden)

Geoff Brown

2007-12-01

Full Text Available Dalhousie University Archives and Special Collections (DUASCSC has been producing Encoded Archival Description (EAD finding aids to describe its archival collections since 2003. The EAD descriptions started as a way to convert the collection of print and electronic (MS Word and WordPerfect finding aids into a stable, software neutral format. As the collection of finding aids grew it became apparent that we needed a way to search these documents beyond what was possible via a basic browse on the DUASC website. As a result, we embarked on a systematic crosswalk of the EAD finding aids into MARC format for inclusion in the Novanet library catalogue. This has facilitated searching and discovery of the materials by a much broader audience of Dalhousie University Library users as well as users from all of the other Novanet member libraries in Nova Scotia and the general public. This article describes the primary motivation for the project and the technical aspects of converting the EAD finding aids into MARC format for inclusion in the Novanet catalogue.

On Elementary Affective Decisions: To Like Or Not to Like, That Is the Question

Science.gov (United States)

Jacobs, Arthur; Hofmann, Markus J.; Kinder, Annette

2016-01-01

Perhaps the most ubiquitous and basic affective decision of daily life is deciding whether we like or dislike something/somebody, or, in terms of psychological emotion theories, whether the object/subject has positive or negative valence. Indeed, people constantly make such liking decisions within a glimpse and, importantly, often without expecting any obvious benefit or knowing the exact reasons for their judgment. In this paper, we review research on such elementary affective decisions (EADs) that entail no direct overt reward with a special focus on Neurocognitive Poetics and discuss methods and models for investigating the neuronal and cognitive-affective bases of EADs to verbal materials with differing degrees of complexity. In line with evolutionary and appraisal theories of (aesthetic) emotions and data from recent neurocognitive studies, the results of a decision tree modeling approach simulating EADs to single words suggest that a main driving force behind EADs is the extent to which such high-dimensional stimuli are associated with the “basic” emotions joy/happiness and disgust. PMID:27933013

Dissipation of triclosan, triclocarban, carbamazepine and naproxen in agricultural soil following surface or sub-surface application of dewatered municipal biosolids

Energy Technology Data Exchange (ETDEWEB)

Al-Rajab, Abdul Jabbar; Sabourin, Lyne [Agriculture and Agri-Food Canada, London, ON N5V 4T3 (Canada); Lapen, David R. [Agriculture and Agri-Food Canada, Ottawa, ON K1A 0C6 (Canada); Topp, Edward, E-mail: ed.topp@agr.gc.ca [Agriculture and Agri-Food Canada, London, ON N5V 4T3 (Canada); Department of Biology, Western University, London, ON N6A 5B7 (Canada)

2015-04-15

In many jurisdictions land application of municipal biosolids is a valued source of nutrients for crop production. The practice must be managed to ensure that crops and adjacent water are not subject to contamination by pharmaceuticals or other organic contaminants. The broad spectrum antimicrobial agents triclosan (TCS) and triclocarban (TCC), the anti-epileptic drug carbamazepine (CBZ), and the nonsteroidal anti-inflammatory drug naproxen (NAP) are widely used and are carried in biosolids. In the present study, the effect of biosolids and depth of placement in the soil profile on the rates of TCS, TCC, CBZ, and NAP dissipation were evaluated under semi-field conditions. Aggregates of dewatered municipal biosolids (DMBs) supplemented with {sup 14}C-labeled residues were applied either on the soil surface or in the subsurface of the soil profile, and incubated over several months under ambient outdoor conditions. The dissipation of TCS, TCC and NAP was significantly faster in sub-surface than surface applied biosolid aggregates. In contrast the dissipation rate for CBZ was the same in surface applied and incorporated aggregates. Overall, the present study has determined a significant effect of depth of placement on the dissipation rate of biodegradable molecules. - Highlights: • We characterized the soil fate of four organic contaminants carried in biosolids. • Biosolids were placed on the soil surface or incorporated within the soil profile. • Naproxen, triclosan and triclocarban were dissipated more rapidly when incorporated. • Depth of placement did not influence the rate of carbamazepine dissipation. • Soil incorporation of biosolids will result in more rapid dissipation of contaminants.

Dissipation of triclosan, triclocarban, carbamazepine and naproxen in agricultural soil following surface or sub-surface application of dewatered municipal biosolids

International Nuclear Information System (INIS)

Al-Rajab, Abdul Jabbar; Sabourin, Lyne; Lapen, David R.; Topp, Edward

2015-01-01

In many jurisdictions land application of municipal biosolids is a valued source of nutrients for crop production. The practice must be managed to ensure that crops and adjacent water are not subject to contamination by pharmaceuticals or other organic contaminants. The broad spectrum antimicrobial agents triclosan (TCS) and triclocarban (TCC), the anti-epileptic drug carbamazepine (CBZ), and the nonsteroidal anti-inflammatory drug naproxen (NAP) are widely used and are carried in biosolids. In the present study, the effect of biosolids and depth of placement in the soil profile on the rates of TCS, TCC, CBZ, and NAP dissipation were evaluated under semi-field conditions. Aggregates of dewatered municipal biosolids (DMBs) supplemented with 14 C-labeled residues were applied either on the soil surface or in the subsurface of the soil profile, and incubated over several months under ambient outdoor conditions. The dissipation of TCS, TCC and NAP was significantly faster in sub-surface than surface applied biosolid aggregates. In contrast the dissipation rate for CBZ was the same in surface applied and incorporated aggregates. Overall, the present study has determined a significant effect of depth of placement on the dissipation rate of biodegradable molecules. - Highlights: • We characterized the soil fate of four organic contaminants carried in biosolids. • Biosolids were placed on the soil surface or incorporated within the soil profile. • Naproxen, triclosan and triclocarban were dissipated more rapidly when incorporated. • Depth of placement did not influence the rate of carbamazepine dissipation. • Soil incorporation of biosolids will result in more rapid dissipation of contaminants

78 FR 58256 - Airworthiness Directives; Eurocopter France Helicopters

Science.gov (United States)

2013-09-23

... revising the RFM to reduce the Velocity Never Exceed (V NE ) indicated airspeed (IAS) limitation. It also... (IAS). EAD 2012-0217-E retains some of the requirements of EAD 2012-0207-E, removes the airspeed... Model AS550C3 helicopters (EASB 01.00.65). EASB 01.00.65 is Revision 3, dated February 4, 2013. EASB 01...

Evaluation of Anthelmintic Resistance and Exhaust Air Dust PCR as a Diagnostic Tool in Mice Enzootically Infected with Aspiculuris tetraptera

Science.gov (United States)

Kapoor, Pratibha; Hayes, Yumiko O; Jarrell, Leslie T; Bellinger, Dwight A; Thomas, Rhiannon D; Lawson, Gregory W; Arkema, Jaclyn D; Fletcher, Craig A; Nielsen, Judith N

2017-01-01

The entry of infectious agents in rodent colonies occurs despite robust sentinel monitoring programs, strict quarantine measures, and stringent biosecurity practices. In light of several outbreaks with Aspiculuris tetraptera in our facilities, we investigated the presence of anthelmintic resistance and the use of exhaust air dust (EAD) PCR for early detection of A. tetraptera infection. To determine anthelmintic resistance, C57BL/6, DBA/2, and NCr nude mice were experimentally inoculated with embryonated A. tetraptera ova harvested from enzootically infected mice, followed by treatment with 150 ppm fenbendazole in feed, 150 ppm fenbendazole plus 5 ppm piperazine in feed, or 2.1 mg/mL piperazine in water for 4 or 8 wk. Regardless of the mouse strain or treatment, no A. tetraptera were recovered at necropsy, indicating the lack of resistance in the worms to anthelmintic treatment. In addition, 10 of 12 DBA/2 positive-control mice cleared the A. tetraptera infection without treatment. To evaluate the feasibility of EAD PCR for A. tetraptera, 69 cages of breeder mice enzootically infected with A. tetraptera were housed on a Tecniplast IVC rack as a field study. On day 0, 56% to 58% of the cages on this rack tested positive for A. tetraptera by PCR and fecal centrifugation flotation (FCF). PCR from EAD swabs became positive for A. tetraptera DNA within 1 wk of placing the above cages on the rack. When these mice were treated with 150 ppm fenbendazole in feed, EAD PCR reverted to pinworm-negative after 1 mo of treatment and remained negative for an additional 8 wk. The ability of EAD PCR to detect few A. tetraptera positive mice was investigated by housing only 6 infected mice on another IVC rack as a field study. The EAD PCR from this rack was positive for A. tetraptera DNA within 1 wk of placing the positive mice on it. These findings demonstrate that fenbendazole is still an effective anthelmintic and that EAD PCR is a rapid, noninvasive assay that may be a useful

A atuação do docente tutor na Educação a Distância

Directory of Open Access Journals (Sweden)

Regina Maria Dutra

2015-06-01

Full Text Available A Educação a Distância (EAD sofreu novo impulso com o surgimento das novas tecnologias de informação e comunicação (TICs, que com a Internet tornou possível o aparecimento de formas alternativas de geração e distribuição do conhecimento. Essa nova modalidade de ensino vem crescendo sistematicamente no interior do país, principalmente nos locais onde não existem instituições de Ensino Superior para atender a demanda local e regional. Com o advento da EAD tornou-se necessário o emprego de inúmeras ferramentas tecnológicas que possibilitam a diminuição da distância física. Entretanto, as tecnologias não são suficientes para que a aprendizagem dos alunos seja eficaz. Sabe-se que educar requer a presença de um profissional que garanta o efetivo e legítimo processo de aprendizagem. Na EAD esse profissional é o docente tutor, do qual precisamos conhecer a função, prática e papel dentro desse sistema. Nesse sentido, este artigo tem como objetivo central discutir o papel do docente tutor presencial na EAD, evidenciando sua relevância social, identificando os aspectos que facilitam ou causam entraves para execução de sua função, além de discutir o papel da tutoria na EAD.

77 FR 67777 - National Oil and Hazardous Substance Pollution Contingency Plan; National Priorities List...

Science.gov (United States)

2012-11-14

... vegetable pickling waste, apple pulp, digester sludge, barrels of spent extracts, brine, the dewatering of... Michigan in Ottawa County. The Site consists of a site entrance, former lagoon area, dewatering lagoons... Company as a municipal garbage dump, liquid waste dewatering facility, and headquarters for its hauling...

Impairment in proverb interpretation as an executive function deficit in patients with amnestic mild cognitive impairment and early Alzheimer's disease.

Science.gov (United States)

Leyhe, Thomas; Saur, Ralf; Eschweiler, Gerhard W; Milian, Monika

2011-01-01

Proverb interpretation is assumed to reflect executive functions. We hypothesized that proverb interpretation is impaired in patients with amnestic mild cognitive impairment (aMCI) diagnosed as single-domain impairment by common neuropsychological testing. We compared performance in a proverb interpretation test in single-domain aMCI patients and patients with early Alzheimer's disease (EAD). The groups with aMCI and EAD performed significantly worse than healthy controls. Both patient groups gave concrete answers with a similar frequency. However, patients with EAD tended to give senseless answers more frequently. Our data suggest that in patients diagnosed as single-domain aMCI, deterioration of executive functions is detectable with subtle and appropriate neuropsychological testing. Implementation of these procedures may improve the early prediction of AD.

An improved electro-acoustic transducer

International Nuclear Information System (INIS)

Leschek, W.C.; Carpenter, P.E.

1975-01-01

That device comprises a tubular metal enclosure, a window and a piezoelectric member, an elongated damping member in contact with said piezoelectric member, an insulating pad mounted in said enclosure, means for pressing said insulating pad against the damping member and, therefore, against the piezoelectric member, and electrical conductors connected to one of the surfaces of said piezoelectric member and to said damping member respectively. That device can be used, in particular, for inspecting the defects, and flaws being formed in the wall of pressurized containers, e.g. nuclear reactors [fr

DFT study on the adsorption behavior and electronic response of AlN nanotube and nanocage toward toxic halothane gas

Science.gov (United States)

Mohammadi, R.; Hosseinian, A.; Khosroshahi, E. Saedi; Edjlali, L.; Vessally, E.

2018-04-01

We have investigated the adsorption of a halothane molecule on the AlN nanotube, and nanocage using density functional theory calculations. We predicted that the halothane molecule tends to be physically adsorbed on the surface of AlN nanotube with adsorption energy (Ead) of -4.2 kcal/mol. The electronic properties of AlN nanotube are not affected by the halothane, and it is not a sensor. But the AlN nanocage is more reactive than the AlN nanotube because of its higher curvature. The halothane tends to be adsorbed on a hexagonal ring, an Alsbnd N bond, and a tetragonal ring of the AlN nanocage. The adsorption ability order is as follows: tetragonal ring (Ead = -14.7 kcal/mol) > Alsbnd N bond (Ead = -12.3 kcal/mol) > hexagonal ring (Ead = -10.1 kcal/mol). When a halothane molecule is adsorbed on the AlN nanocage, its electrical conductivity is increased, demonstrating that it can yield an electronic signal at the presence of this molecule, and can be employed in chemical sensors. The AlN nanocage benefits from a short recovery time of about 58 ms at room temperature.

Performance of the engineering analysis and data system 2 common file system

Science.gov (United States)

Debrunner, Linda S.

1993-01-01

The Engineering Analysis and Data System (EADS) was used from April 1986 to July 1993 to support large scale scientific and engineering computation (e.g. computational fluid dynamics) at Marshall Space Flight Center. The need for an updated system resulted in a RFP in June 1991, after which a contract was awarded to Cray Grumman. EADS II was installed in February 1993, and by July 1993 most users were migrated. EADS II is a network of heterogeneous computer systems supporting scientific and engineering applications. The Common File System (CFS) is a key component of this system. The CFS provides a seamless, integrated environment to the users of EADS II including both disk and tape storage. UniTree software is used to implement this hierarchical storage management system. The performance of the CFS suffered during the early months of the production system. Several of the performance problems were traced to software bugs which have been corrected. Other problems were associated with hardware. However, the use of NFS in UniTree UCFM software limits the performance of the system. The performance issues related to the CFS have led to a need to develop a greater understanding of the CFS organization. This paper will first describe the EADS II with emphasis on the CFS. Then, a discussion of mass storage systems will be presented, and methods of measuring the performance of the Common File System will be outlined. Finally, areas for further study will be identified and conclusions will be drawn.

Cingulum correlates of cognitive functions in patients with mild cognitive impairment and early Alzheimer's disease: a diffusion spectrum imaging study.

Science.gov (United States)

Lin, Yi-Cheng; Shih, Yao-Chia; Tseng, Wen-Yih I; Chu, Yu-Hsiu; Wu, Meng-Tien; Chen, Ta-Fu; Tang, Pei-Fang; Chiu, Ming-Jang

2014-05-01

Diffusion spectrum imaging (DSI) of MRI can detect neural fiber tract changes. We investigated integrity of cingulum bundle (CB) in patients with mild cognitive impairment (MCI) and early Alzheimer's disease (EAD) using DSI tractography and explored its relationship with cognitive functions. We recruited 8 patients with MCI, 9 with EAD and 15 healthy controls (HC). All subjects received a battery of neuropsychological tests to access their executive, memory and language functions. We used a 3.0-tesla MRI scanner to obtain T1- and T2-weighted images for anatomy and used a pulsed gradient twice-refocused spin-echo diffusion echo-planar imaging sequence to acquire DSI. Patients with EAD performed significantly poorer than the HC on most tests in executive and memory functions. Significantly smaller general fractional anisotropy (GFA) values were found in the posterior and inferior segments of left CB and of the anterior segment of right CB of the EAD compared with those of the HC. Spearman's correlation on the patient groups showed that GFA values of the posterior segment of the left CB were significantly negatively associated with the time used to complete Color Trails Test Part II and positively correlated with performance of the logical memory and visual reproduction. GFA values of inferior segment of bilateral CB were positively associated with the performance of visual recognition. DSI tractography demonstrates significant preferential degeneration of the CB on the left side in patients with EAD. The location-specific degeneration is associated with corresponding declines in both executive and memory functions.

Exhaust Air Dust Monitoring is Superior to Soiled Bedding Sentinels for the Detection of Pasteurella pneumotropica in Individually Ventilated Cage Systems.

Science.gov (United States)

Miller, Manuel; Ritter, Brbel; Zorn, Julia; Brielmeier, Markus

2016-11-01

Reliable detection of unwanted organisms is essential for meaningful health monitoring in experimental animal facilities. Currently, most rodents are housed in IVC systems, which prevent the aerogenic transmission of pathogens between cages. Typically soiled-bedding sentinels (SBS) exposed to soiled bedding collected from a population of animals within an IVC rack are tested as representatives, but infectious agents often go undetected due to inefficient transmission. Pasteurellaceae are among the most prevalent bacterial pathogens isolated from experimental mice, and the failure of SBS to detect these bacteria is well established. In this study, we investigated whether analysis of exhaust air dust (EAD) samples by using a sensitive and specific real-time PCR assay is superior to conventional SBS monitoring for the detection of Pasteurella pneumotropica (Pp) infections. In a rack with a known prevalence of Pp-positive mice, weekly EAD sampling was compared with the classic SBS method over 3 mo. In 6 rounds of testing, with a prevalence of 5 infected mice in each of 7 cages in a rack of 63 cages, EAD PCR detected Pp at every weekly time point; SBS failed to detect Pp in all cases. The minimal prevalence of Pp-infected mice required to obtain a reliable positive result by EAD PCR testing was determined to be 1 in 63 cages. Reliable detection of Pp was achieved after only 1 wk of exposure. Analysis of EAD samples by real-time PCR assay provides a sensitive, simple, and reliable approach for Pp identification in laboratory mice.

Thermophilic anaerobic co-digestion of sewage sludge with grease waste: Effect of long chain fatty acids in the methane yield and its dewatering properties

International Nuclear Information System (INIS)

Silvestre, G.; Illa, J.; Fernández, B.; Bonmatí, A.

2014-01-01

Highlights: • Thermophilic anaerobic codigestion of sewage sludge and grease waste (GW) doubles methane yield. • High GW doses in the influent leads to instability and LCFA accumulation in the effluent. • GW addition promotes acetoclastic activity whilst worsening the hydrogenothrophic activity. • The mesophilic codigestion with GW performs better than the thermophilic one. - Abstract: Thermophilic co-digestion of sewage sludge with three different doses of trapped grease waste (GW) from the pre-treatment of a WWTP has been assessed in a CSTR bench-scale reactor. After adding 12% and 27% of grease waste (on COD basis), the organic loading rate increased from 2.2 to 2.3 and 2.8 kg COD m −3 d −1 respectively, and the methane yield increased 1.2 and 2.2 times. Further GW increase (37% on COD basis) resulted in an unstable methane yield and in long chain fatty acids (LCFA) accumulation. Although this inestability, the presence of volatile fatty acids in the effluent was negligible, showing good adaptation to fats of the thermophilic biomass. Nevertheless, the presence of LCFA in the effluent worsens its dewatering properties. Specific methanogenic activity tests showed that the addition of grease waste ameliorates the acetoclastic activity in detriment of the hydrogenotrophic activity, and suggests that the tolerance to LCFA can be further enhanced by slowly increasing the addition of lipid-rich materials

Filtros plantados com macrófitas de fluxo vertical aplicados na mineralização e desaguamento de lodo de tanque séptico Vertical flow constructed wetlands for septic sludge mineralization and dewatering

Directory of Open Access Journals (Sweden)

Carla Suntti

2011-03-01

Full Text Available O lodo acumulado no interior de tanques sépticos deve passar por um tratamento antes de sua adequada disposição final, pois apresenta uma fração da matéria orgânica não estabilizada, elevado teor de umidade e organismos patogênicos. Como alternativa para o tratamento do lodo, os filtros plantados com macrófitas são uma tecnologia promissora. Para se avaliar o potencial dos filtros no desaguamento e mineralização do lodo de tanque séptico, foram construídos dois filtros pilotos (F1 e F2 aplicando-se duas taxas de sólidos totais (ST - F1: 250 kgST.m-2.ano-1; F2: 125 kgST.m-2.ano-1. Os resultados revelaram que o F2 apresentou melhor desempenho em relação ao F1 em termos de remoção de sólidos totais (96%, demanda química de oxigênio (99% e nitrogênio amoniacal (72%. O F2 proporcionou melhor desaguamento, com 67% de umidade no lodo acumulado no leito e 33% de sólidos totais.The accumulated sludge in septic tanks has to be treated before the adequate final disposal, because of its high concentration of non-established organic matter, elevated content of moisture and pathogenic organisms. As an alternative to the treatment of sludge, the vertical flow constructed wetlands are a promising technology. To evaluate the potential of the filters in dewatering and mineralization of septic tank sludge, two pilot-scale constructed wetlands (CW1 and CW2 were implanted according with two total solids loads (TS - CW1: 250 kgTS.m-2.year-1; CW2: 125kgTS.m-2.year-1. The results demonstrated that the CW2 had better efficiencies compared with CW1, in terms of total solids (96%, chemical oxygen demand (99% and ammonia (72% removal. CW2 also provided a better dewatering, with moisture of 67% in accumulated sludge and 33% of total solids.

Impairment in Proverb Interpretation as an Executive Function Deficit in Patients with Amnestic Mild Cognitive Impairment and Early Alzheimer’s Disease

Directory of Open Access Journals (Sweden)

Thomas Leyhe

2011-01-01

Full Text Available Background/Aims: Proverb interpretation is assumed to reflect executive functions. We hypothesized that proverb interpretation is impaired in patients with amnestic mild cognitive impairment (aMCI diagnosed as single-domain impairment by common neuropsychological testing. Methods: We compared performance in a proverb interpretation test in single-domain aMCI patients and patients with early Alzheimer’s disease (EAD. Results: The groups with aMCI and EAD performed significantly worse than healthy controls. Both patient groups gave concrete answers with a similar frequency. However, patients with EAD tended to give senseless answers more frequently. Conclusions: Our data suggest that in patients diagnosed as single-domain aMCI, deterioration of executive functions is detectable with subtle and appropriate neuropsychological testing. Implementation of these procedures may improve the early prediction of AD.

Nuclear dewatering

International Nuclear Information System (INIS)

Anon.

1989-01-01

The Sizewell 'B' Nuclear Power Station, the first in a new family of PWR (Pressurised Water Reactor) stations in the UK, is currently under construction on the Suffolk coast. One of the first civil engineering tasks associated with the power station construction was the necessity to lower the water table by 17-18 m over an area of approximately 8 hectares to allow the excavation for the foundations to be carried out in the dry. The way chosen to do this was to construct a diaphragm wall around the site area. This had the least effect on surrounding sites -the Sizewell-A station and various nature reserves and wetlands. The reasons for the choice of method are discussed. Following the construction of the wall the water was pumped out from within the diaphragm wall in January 1988. (author)

Extracellular polymeric substances (EPS) producing bacterial strains of municipal wastewater sludge: isolation, molecular identification, EPS characterization and performance for sludge settling and dewatering.

Science.gov (United States)

Bala Subramanian, S; Yan, S; Tyagi, R D; Surampalli, R Y

2010-04-01

Wastewater treatment plants often face the problems of sludge settling mainly due to sludge bulking. Generally, synthetic organic polymer and/or inorganic coagulants (ferric chloride, alum and quick lime) are used for sludge settling. These chemicals are very expensive and further pollute the environment. Whereas, the bioflocculants are environment friendly and may be used to flocculate the sludge. Extracellular polymeric substances (EPS) produced by sludge microorganisms play a definite role in sludge flocculation. In this study, 25 EPS producing strains were isolated from municipal wastewater treatment plant. Microorganisms were selected based on EPS production properties on solid agar medium. Three types of EPS (slime, capsular and bacterial broth mixture of both slime and capsular) were harvested and their characteristics were studied. EPS concentration (dry weight), viscosity and their charge (using a Zetaphoremeter) were also measured. Bioflocculability of obtained EPS was evaluated by measuring the kaolin clay flocculation activity. Six bacterial strains (BS2, BS8, BS9, BS11, BS15 and BS25) were selected based on the kaolin clay flocculation. The slime EPS was better for bioflocculation than capsular EPS and bacterial broth. Therefore, extracted slime EPS (partially purified) from six bacterial strains was studied in terms of sludge settling [sludge volume index (SVI)] and dewatering [capillary suction time (CST)]. Biopolymers produced by individual strains substantially improved dewaterability. The extracted slime EPS from six different strains were partially characterized. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Defense Horizons. No. 73. September 2012. Toward the Printed World: Additive Manufacturing and Implications for National Security

Science.gov (United States)

2012-09-01

allowing it to dry or baking it in a kiln . A modern factory would take a block of raw material and then use machinery to pare away un- necessary...implication that has not yet been discussed with- in AM technology circles is personalized body enhance- ment. Inorganic hybrid materials ( electrical , optical...equipment eadS aircraft and defense company envisiontec dental equipment manufacturer fisher-Price toy company ford Car manufacturer general electric

Toward the Printed World: Additive Manufacturing and Implications for National Security (Defense Horizons, Number 73)

Science.gov (United States)

2012-09-01

allowing it to dry or baking it in a kiln . A modern factory would take a block of raw material and then use machinery to pare away un- necessary...implication that has not yet been discussed with- in AM technology circles is personalized body enhance- ment. Inorganic hybrid materials ( electrical , optical...equipment eadS aircraft and defense company envisiontec dental equipment manufacturer fisher-Price toy company ford Car manufacturer general electric

Recovery, restoration, and development of an enhancement plan for the Leading Creek watershed after dewatering of the Meigs number-sign 31 coal mine in Ohio

International Nuclear Information System (INIS)

Cherry, D.S.; Hassel, J.H. Van; Yeager, M.M.; Babendreier, J.E.; Currie, R.J.; Astin, L.E.; Lynde, S.R.

1995-01-01

Following the flooding of the Meigs number-sign 31 deep coal mine in Meigs County, Ohio, a proactive plan was developed to evaluate effects of initial dewatering, recovery, and development of a watershed enhancement plan. Approximately half of the 31-mile Leading Creek mainstem received coal mine discharge of high conductivity, low pH, high metals and total suspended solids loading. Most forms of aquatic life were depleted in the impacted areas of the creek. After three years since the incident, many forms of benthic macroinvertebrates and fish have returned to the creek, and sediments have been purged of metal loading by storm water events. The enhancement plan involves a reconnaissance of the creek and tributaries pinpointing areas of agricultural sedimentation and abandoned mined land (AML) influences in the lower half. Research activities involved sampling water and sediment in 10 stations of the creek and 17 major tributaries. The tributaries were addressed as point source discharges with water/sediment toxicity testing conducted. In-situ testing included growth impairment evaluation of Asian clams at 27 stations in the watershed. Several tributaries were intermittently toxic depending upon rainfall and the degree of AML input. Benthic macroinvertebrate assembles in most tributaries were stressed and comprised 0--3 taxa. Erosion/sedimentation loading was being addressed by hydrological modeling of the creek, land use management/habitat assessment, and data management by geographic information systems

A high-fidelity model for coupling flow and mechanical deformation of the porous paper web - a key to improved understanding of dewatering and rewet at the press section in paper making

Energy Technology Data Exchange (ETDEWEB)

Hao, Y. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Trebotich, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wang, W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Xu, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Turpin, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2017-04-05

The U.S. pulp and paper industry is the third-largest manufacturing user of energy, with an energy demand of 2,540 trillion Btu in 2010. Within the papermaking process, drying consumes over 400 trillion Btu annually which makes it one of the largest energy saving opportunities. In the 2014 Forest Products Industry Technology Roadmap, it is concluded that increasing the paper web solid content entering the dryer section from the current 45- 55 percent to approaching 65 percent, which would save 1.0 MMBtu per ton or 20 percent of the energy used in drying, is one of the most needed technology breakthroughs to achieve a more sustainable approach for manufacturing pulp and paper products. Achieving such significant energy savings highly depends on understanding the fundamental dynamics of the wet press process and then developing optimized solutions for design of more energy-efficient press processes and equipment. The objective of this project is to develop reliable computational capabilities to accurately simulate the flow of water from/to the porous pulp medium (dewatering/rewetting) during the pressing process in paper making.

Educação superior a distância no Brasil: uma construção consorciada e em rede

Directory of Open Access Journals (Sweden)

Luiz Roberto Rodrigues Martins

2006-03-01

Full Text Available Este artigo descreve a experiência de implantação da política de fomento aos cursos de Graduação a Distância (EAD no Brasil adotada pela Secretaria de Educação a Distância do Ministério da Educação (SEED/MEC a partir de 2004. Essa política prioriza a criação de cursos de licenciatura e a distância. Analisaremos essa experiência pioneira e ainda não consolidada, buscando interpretar os fatores que dificultam a institucionalização da EAD no ensino superior. Nesse trabalho analisaremos algumas alternativas de institucionalização apresentadas pelos oito consórcios participantes da Chamada Pública 001/2004 SEED/MEC na reunião de trabalho realizada em abril de 2005. As proposições dos consórcios, encaminhadas ao MEC pela UniRede, pretendem assegurar a continuidade da política pública de fomento à EAD no ensino superior público, garantindo a continuidade dos cursos oferecidos e a ampliação de vagas nos próximos anos. Palavras-chave: Políticas públicas, educação a distância, institucionalização da EAD.

EADS Roadmap for Launch Vehicles

Science.gov (United States)

Eymar, Patrick; Grimard, Max

2002-01-01

still think about the future, especially at industry level in order to make the most judicious choices in technologies, vehicle types as well as human resources and facilities specialization (especially after recent merger moves). and production as prime contractor, industrial architect or stage provider have taken benefit of this expertise and especially of all the studies ran under national funding and own financing on reusable vehicles and ground/flight demonstrators have analyzed several scenarios. VEHICLES/ASTRIUM SI strategy w.r.t. launch vehicles for the two next decades. Among the main inputs taken into account of course visions of the market evolutions have been considered, but also enlargement of international cooperations and governments requests and supports (e.g. with the influence of large international ventures). 1 patrick.eymar@lanceurs.aeromatra.com 2

The ''Gent'' stacked filter unit (SFU) sampler for the collection of atmospheric aerosols in two size fractions: Description and instructions for installation and use

International Nuclear Information System (INIS)

Maenhaut, W.; Francois, F.; Cafmeyer, J.

1994-01-01

This report contains a description and general instructions for the installation and use of the ''Gent'' Stacked Filter Unit (SFU) PM10 sampler. The sampler operates at a flow rate of 16 litres per min. It collects particulates which have an equivalent aerodynamic diameter (EAD) of less than 10 μm in separate ''coarse'' (2-10 μm EAD) and ''fine'' ( 10 μm EAD particles is accomplished by a PM10 pre-impaction stage upstream of the stacked filter cassette. The air is drawn through the sampler by means of a diaphragm vacuum pump, which is enclosed in a special housing together with a needle valve, vacuum gauge, flow meter, volume meter, time switch (for interrupted sampling) and hour meter. A list of manufacturers of the various components of the sampler is also given. (author). 4 figs, 1 tab

Methods for evaluation of mechanical stress condition of materials

Directory of Open Access Journals (Sweden)

Mirchev Yordan

2018-01-01

Full Text Available Primary attention is given to the following methods: method by drilling cylindrical holes (drill method and integrated ultrasonic method using volume (longitudinal and transverse, surface, and sub-surface waves. Drill method allows determination of residual mechanical stress in small depth of material surfaces, assessing type, size, and orientation of principal stresses. For the first time, parallel studies are carried out of mechanical stress in materials using the electroacoustic effect of volume, surface and sub-surface waves on the one hand, and effective mechanical stresses on the other. The experimental results present electroacoustic coefficients for different types of waves in the material of gas pipeline tube of 243 mm diameter and 14 mm thickness. These are used to evaluate mechanical stresses in pipelines, according to active GOST standards.

The Role of AR- and VDR-Modulated miRNAs in Sensitization of Prostate Cancer Cells to Therapy

Science.gov (United States)

2012-10-01

13]. Thus, at the time of diagnosis of PCa, he majority of men have declining serum T and low D3 levels, eading to the hypothesis that the two...translatability of PPARA mRNA (Fig. 1), eading to increases in PPARA protein expression, which in turn romotes neutral lipid synthesis and energy storage. This is...surrounding lymph nodes from the primary tumors before establishing bone metastases. This linear temporal relationship is not recapitulated using other

Transient Outward K+ Current (Ito) Underlies the Right Ventricular Initiation of Polymorphic Ventricular Tachycardia in a Transgenic Rabbit Model of Long-QT Syndrome Type 1.

Science.gov (United States)

Choi, Bum-Rak; Li, Weiyan; Terentyev, Dmitry; Kabakov, Anatoli Y; Zhong, Mingwang; Rees, Colin M; Terentyeva, Radmila; Kim, Tae Yun; Qu, Zhilin; Peng, Xuwen; Karma, Alain; Koren, Gideon

2018-06-01

Sudden death in long-QT syndrome type 1 (LQT1), an inherited disease caused by loss-of-function mutations in KCNQ1, is triggered by early afterdepolarizations (EADs) that initiate polymorphic ventricular tachycardia (pVT). We investigated ionic mechanisms that underlie pVT in LQT1 using a transgenic rabbit model of LQT1. Optical mapping, cellular patch clamping, and computer modeling were used to elucidate the mechanisms of EADs in transgenic LQT1 rabbits. The results showed that shorter action potential duration in the right ventricle (RV) was associated with focal activity during pVT initiation. RV cardiomyocytes demonstrated higher incidence of EADs under 50 nmol/L isoproterenol. Voltage-clamp studies revealed that the transient outward potassium current (I to ) magnitude was 28% greater in RV associated with KChiP2 but with no differences in terms of calcium-cycling kinetics and other sarcolemmal currents. Perfusing with the I to blocker 4-aminopyridine changed the initial focal sites of pVT from the RV to the left ventricle, corroborating the role of I to in pVT initiation. Computer modeling showed that EADs occur preferentially in the RV because of the larger conductance of the slow-inactivating component of I to , which repolarizes the membrane potential sufficiently rapidly to allow reactivation of I Ca,L before I Kr has had sufficient time to activate. I to heterogeneity creates both triggers and an arrhythmogenic substrate in LQT1. In the absence of I Ks , I to interactions with I Ca,L and I Kr promote EADs in the RV while prolonging action potential duration in the left ventricle. This heterogeneity of action potential enhances dispersion of refractoriness and facilitates conduction blocks that initiate pVTs. © 2018 American Heart Association, Inc.

Identification and field evaluation of fermentation volatiles from wine and vinegar that mediate attraction of spotted wing Drosophila, Drosophila suzukii.

Science.gov (United States)

Cha, Dong H; Adams, Todd; Rogg, Helmuth; Landolt, Peter J

2012-11-01

Previous studies suggest that olfactory cues from damaged and fermented fruits play important roles in resource recognition of polyphagous spotted wing Drosophila flies (SWD), Drosophila suzukii (Matsumura) (Diptera: Drosophilidae). They are attracted to fermented sweet materials, such as decomposing fruits but also wines and vinegars, and to ubiquitous fermentation volatiles, such as acetic acid and ethanol. Gas chromatography coupled with electroantennographic detection (GC-EAD), gas chromatography-mass spectrometry (GC-MS), two-choice laboratory bioassays, and field trapping experiments were used to identify volatile compounds from wine and vinegar that are involved in SWD attraction. In addition to acetic acid and ethanol, consistent EAD responses were obtained for 13 volatile wine compounds and seven volatile vinegar compounds, with all of the vinegar EAD-active compounds also present in wine. In a field trapping experiment, the 9-component vinegar blend and 15-component wine blend were similarly attractive when compared to an acetic acid plus ethanol mixture, but were not as attractive as the wine plus vinegar mixture. In two-choice laboratory bioassays, 7 EAD-active compounds (ethyl acetate, ethyl butyrate, ethyl lactate, 1-hexanol, isoamyl acetate, 2-methylbutyl acetate, and ethyl sorbate), when added singly to the mixture at the same concentrations tested in the field, decreased the attraction of SWD to the mixture of acetic acid and ethanol. The blends composed of the remaining EAD-active chemicals, an 8-component wine blend [acetic acid + ethanol + acetoin + grape butyrate + methionol + isoamyl lactate + 2-phenylethanol + diethyl succinate] and a 5-component vinegar blend [acetic acid + ethanol + acetoin + grape butyrate + 2-phenylethanol] were more attractive than the acetic acid plus ethanol mixture, and as attractive as the wine plus vinegar mixture in both laboratory assays and the field trapping experiment. These results indicate that these

The flavonoid content and antiproliferative, hypoglycaemic, anti-inflammatory and free radical scavenging activities of Annona dioica St. Hill

Directory of Open Access Journals (Sweden)

Formagio Anelise S N

2013-01-01

Full Text Available Abstract Background Annona dioica St. Hill (Annonacaeae is a Brazilian plant used in folk medicine for the treatment of several types of rheumatisms and diarrhoea. The focus of this work was to evaluate the in vitro antiproliferative and antioxidant activity and the in vivo hypoglycaemic and anti-inflammatory activity of A. dioica and identify the principal constituents of this plant. Methods The crude methanol extract (EAD and hexane (HF, chloroform (CF, ethyl acetate (EAF and hydromethanol fractions (HMF were evaluated for free radical scavenging activity using the DPPH assay. The EAD and EAF were assayed for hypoglycaemic activity in rats. The EAD was tested in an antiproliferation assay and for anti-inflammatory effects in paw oedema, in addition to myeloperoxidase activity induced by carrageenan (Cg in mice. The EAF was assayed using chromatographic methods. Results The fractionation of the EAF through chromatographic methods identified derivatives of the flavonoids quercetin and kaempferol. Among all the tested fractions, the ethyl acetate and hydromethanol fractions were the most potent, exhibiting an IC50 of 8.53 and 10.57 μg/mL, respectively, which is comparable to that of the commercial antioxidant butylated hydroxytoluene (BHT. The oral administration of the EAD (100 mg/kg and EAF (15 mg/kg inhibited the increase of glucose levels, resulting in a hypoglycaemic effect. The EAD (30 to 300 mg/kg exhibited an anti-oedematogenic effect in Cg-induced paw oedema in a time- and dose-dependent manner. The results showed a reduction of MPO activity by A. dioica 6 h after the induction of paw oedema at all doses tested with maximal inhibition at 300 mg/kg. Conclusions Our results reveal for the first time that compounds contained in the A. dioica leaves exert anti-inflammatory, hypoglycaemic, antiproliferative, and antioxidant effects. The antioxidant activity may be associated with the presence of flavonoids.

A model of cardiac ryanodine receptor gating predicts experimental Ca2+-dynamics and Ca2+-triggered arrhythmia in the long QT syndrome

Science.gov (United States)

Wilson, Dan; Ermentrout, Bard; Němec, Jan; Salama, Guy

2017-09-01

Abnormal Ca2+ handling is well-established as the trigger of cardiac arrhythmia in catecholaminergic polymorphic ventricular tachycardia and digoxin toxicity, but its role remains controversial in Torsade de Pointes (TdP), the arrhythmia associated with the long QT syndrome (LQTS). Recent experimental results show that early afterdepolarizations (EADs) that initiate TdP are caused by spontaneous (non-voltage-triggered) Ca2+ release from Ca2+-overloaded sarcoplasmic reticulum (SR) rather than the activation of the L-type Ca2+-channel window current. In bradycardia and long QT type 2 (LQT2), a second, non-voltage triggered cytosolic Ca2+ elevation increases gradually in amplitude, occurs before overt voltage instability, and then precedes the rise of EADs. Here, we used a modified Shannon-Puglisi-Bers model of rabbit ventricular myocytes to reproduce experimental Ca2+ dynamics in bradycardia and LQT2. Abnormal systolic Ca2+-oscillations and EADs caused by SR Ca2+-release are reproduced in a modified 0-dimensional model, where 3 gates in series control the ryanodine receptor (RyR2) conductance. Two gates control RyR2 activation and inactivation and sense cytosolic Ca2+ while a third gate senses luminal junctional SR Ca2+. The model predicts EADs in bradycardia and low extracellular [K+] and cessation of SR Ca2+-release terminate salvos of EADs. Ca2+-waves, systolic cell-synchronous Ca2+-release, and multifocal diastolic Ca2+ release seen in subcellular Ca2+-mapping experiments are observed in the 2-dimensional version of the model. These results support the role of SR Ca2+-overload, abnormal SR Ca2+-release, and the subsequent activation of the electrogenic Na+/Ca2+-exchanger as the mechanism of TdP. The model offers new insights into the genesis of cardiac arrhythmia and new therapeutic strategies.

Formação docente e educação a distância: um estudo do cenário educativo de Santa Catarina

Directory of Open Access Journals (Sweden)

Rafael Pereira Ocampo Moré

2012-04-01

Full Text Available DOI: http://dx.doi.org/10.5007/2175-8077.2012v14n32p9 A formação docente é fator preponderante na luta pela qualidade na educação do Brasil. A partir da promulgação da Lei de Diretrizes e Bases (LDB, em 1996, tem-se o desafio de formar novos professores e, para isso, verifica-se na Educação a Distância (EaD uma excelente alternativa de acesso à  educação superior pública. A EaD é definida como proposta educativa que utiliza tecnologias para diminuir a distância entre as Instituições de Ensino Superior (IES e os alunos, e é nesse contexto que surge a Universidade Aberta do Brasil (UAB, que atualmente é a principal política de formação docente por meio da EaD. O objetivo do trabalho é apresentar as políticas de formação docente inseridas no estado de Santa Catarina, sendo detalhada a UAB no cenário brasileiro e catarinense e analisada a inserção de TICs nas escolas catarinense como mecanismo de promoção e estímulo ao uso da EaD como proposta educativa.

Um Enfoque Empreendedor Para a Educação à Distância - LED/UFSC

Directory of Open Access Journals (Sweden)

Anderson Antônio Mattos Martins

2002-03-01

Full Text Available O presente artigo tem por finalidade apontar, dentre as novas modalidades de ensino, a Educação a Distância (EAD como melhor alternativa para o mercado de trabalho cada vez mais sofisticado e globalizado, já que é concebida como uma construção criativa e reflexiva que propicia a democratização educacional. Inicialmente são analisados alguns aspectos da sociedade contemporânea em cujo contexto a educação passa por adaptabilidades em função das modernas formas de comunicação eletrônica, entre outras. Em seguida, fazem-se reflexões sobre EAD, Empreendedorismo e Competências, resgatando origem e conceitos. Também apresenta-se o Laboratório de Ensino a Distância (LED que desenvolve estratégias e metodologias de EAD em ambientes multimídias integrados por redes de comunicação. Por fim, considera-se um novo caminho para a educação: a EAD que possibilita o atendimento às expectativas do mundo do trabalho, através da adoção de currículos relevantes, flexíveis e adaptados às exigências sociais e individuais. PALAVRAS-CHAVE: Educação a Distância, Empreendedorismo, Competências

Dewaterability of five sewage sludges in Guangzhou conditioned with Fenton's reagent/lime and pilot-scale experiments using ultrahigh pressure filtration system.

Science.gov (United States)

Liang, Jialin; Huang, Shaosong; Dai, Yongkang; Li, Lei; Sun, Shuiyu

2015-11-01

Sludge conditioning with Fenton's reagent and lime is a valid method for sludge dewatering. This study investigated the influence of different organic matter content sludge on sludge dewatering and discussed the main mechanism of sludge conditioning by combined Fenton's reagent and lime. The results indicated that the specific resistance to filterability (SRF) of sludge was reduced efficiently by approximately 90%, when conditioned with Fenton's reagent and lime. Through single factor experiments, the optimal conditioning combinations were found. In addition, the relationship between VSS% and consumption of the reagents was detected. Furthermore, it was also demonstrated that the SRF and filtrate TOC values had a significant correlation with VSS% of sludge (including raw and conditioned). The main mechanism of sludge dewatering was also investigated. Firstly, it revealed that the dewaterability of sludge was closely correlated to extracellular polymeric substances (EPS) and bound water contents. Secondly, the results of scanning electron microscopy (SEM) stated that sludge particles were to be smaller and thinner after conditioning. And this structure could easily form outflow channels for releasing free water. Additionally, with the ultrahigh pressure filtration system, the water content of sludge cake conditioned with Fenton's reagent and lime could be reduced to below 50%. Moreover, the economic assessment shows that Fenton's reagent and lime combined with ultrahigh pressure filtration system can be an economical and viable technology for sewage sludge dewatering. Finally, three types of sludge were classified: (1) Fast to dewater; (2) Moderately fast to dewater; (3) Slow to dewater sludge. Copyright © 2015 Elsevier Ltd. All rights reserved.

Characterization of alumina suspensions by electroacoustics

Energy Technology Data Exchange (ETDEWEB)

Galassi, C.; Roncari, E.; Greenwood, R.; Piancastelli, A. [CNR, Faenza (Italy). Research Inst. for Ceramics Technology

1997-12-31

Using the acoustophoresis technique three different dispersants were selected to investigate the effect of the volume fraction of the suspension on the minimum amount of dispersant required to give the maximum zeta potential. No effect was detected over a volume fraction range 0.11 to 0.35. The acoustosizer was used to screen many dispersants for alumina in a relatively short time. From the viewpoint that the most stable suspensions are those with the greatest zeta potentials, then the following dispersants can be recommended: Reotan LA (0.25 mg/m{sup 2}) Dolapix CA (0.20 mg/m{sup 2}) and Dolapix PC33 (0.30 mg/m{sup 2}). Vanisperse and Borresperse are poor. Polyacrylic acid and polymethacrylic acid were better than some commercially available products. (orig.) 2 refs.

Two-dimensional electroacoustic waves in silicene

Science.gov (United States)

Zhukov, Alexander V.; Bouffanais, Roland; Konobeeva, Natalia N.; Belonenko, Mikhail B.

2018-01-01

In this letter, we investigate the propagation of two-dimensional electromagnetic waves in a piezoelectric medium built upon silicene. Ultrashort optical pulses of Gaussian form are considered to probe this medium. On the basis of Maxwell's equations supplemented with the wave equation for the medium's displacement vector, we obtain the effective governing equation for the vector potential associated with the electromagnetic field, as well as the component of the displacement vector. The dependence of the pulse shape on the bandgap in silicene and the piezoelectric coefficient of the medium was analyzed, thereby revealing a nontrivial triadic interplay between the characteristics of the pulse dynamics, the electronic properties of silicene, and the electrically induced mechanical vibrations of the medium. In particular, we uncovered the possibility for an amplification of the pulse amplitude through the tuning of the piezoelectric coefficient. This property could potentially offer promising prospects for the development of amplification devices for the optoelectronics industry.

Sistema Personalizado de Ensino, Educação à Distância e aprendizagem centrada no aluno

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João Claudio Todorov

Full Text Available O Sistema Personalizado de Ensino (PSI, amplamente utilizado nos anos 1970, e a Educação à Distância (EAD são duas metodologias de ensino que rompem com modelos tradicionais de educação, nos quais o centro crítico de transmissão de informação é o professor. O presente trabalho apresenta as principais características dessas duas formas de ensinar, ressaltando suas similaridades. Alguns estudos nos quais PSI e EAD foram utilizados em conjunto são descritos e as vantagens de tal junção são discutidas. Sugere-se, ao final deste trabalho, que o uso conjunto do PSI e da EAD pode ser uma forma viável de disseminação e democratização de um ensino de qualidade, alicerçado em evidências empíricas de sua eficácia.

Volume reduction of filter media at Susquehanna steam and electric station

International Nuclear Information System (INIS)

Boris, G.F.; Hettinger, J.

1990-01-01

This paper describes the joint efforts between Pennsylvania Power ampersand Light (PPQL) and Scientific Ecology Group, Inc. (SEG) to reduce the volume of waste shipped to the burial site by the Susquehanna Steam and Electric Station (SSES) and the resulting savings realized as a result. The filter media used at SSES for its radwaste filters is composed of a mix of anion and cation powered resins, powered carbon, diatomaceous earth and a fibrous overlay. Due to the nature of this waste stream, dewatering was difficult using systems previously available in the industry. Thus, processing was accomplished by decanting (to concentrate the waste) and solidification. In the continuing effort to dewater wastes of this nature, SEG developed a new fabric filter dewatering system (RDU). To investigate its potential use in large containers, this dewatering system was installed in drum-size high integrity containers and used to test its dewatering capabilities on actual SSES waste. Promising results from these tests warranted a full-scale test. This proved successful and implementation of this processing scheme was immediate. Cost savings were substantial in transportation, burial and processing costs as well as personnel exposure. Also, additional waste volume reduction was found due to the volume reduction capability of the dewatering system (equivalent volume of new filter media approximately 1.2 times that of dewatered product volume). Additional savings resulted from SSES's continuing effort to minimize radwaste generation. Combined, these have reduced the number of shipments of filter media in 1989 to sixty percent of the number made in 1988 and have reduced costs by approximately fifty percent. 4 figs., 1 tab

Terahertz Solitons in Biomolecular Systems and their Excitation by External Electromagnetic Field

Directory of Open Access Journals (Sweden)

Bugay А.N.

2015-01-01

Full Text Available Nonlinear dynamics of charge and acoustic excitations in cellular microtubules is considered. Different types of nonlinear solitary waves were studied taking account for dissipation. The mechanism of electro-acoustic pulse excitation by external electromagnetic field of terahertz frequency is recognized.

Atomizer

DEFF Research Database (Denmark)

Fixed stereo electroacoustic music, included in Robert Voisey’s (Curator) VoxNovus 60×60 Dance, 60×60 2010 International Mix and 60×60 Sanguine Mix projects. Performed internationally, including Stratford Circus, London, UK. Full performance listings and press available online....

The GNC Measurement System for the Automated Transfer Vehicle

Science.gov (United States)

Roux, Y.; da Cunha, P.

The Automated Transfer Vehicle (ATV) is a European Space Agency (ESA) funded spacecraft developed by EADS Space Transportation as prime contractor for the space segment together with major European industrial partners, in the frame of the International Space Station (ISS). Its mission objective is threefold : to supply the station with fret and propellant, to reboost ISS to a higher orbit and to dispose of waste from the station. The ATV first flight, called Jules Verne and planned on 2005, will be the first European Vehicle to perform an orbital rendezvous. The GNC Measurement System (GMS) is the ATV on board function in charge of the measurement data collection and preconditioning for the navigation, guidance and control (GNC) algorithms. The GMS is made up of hardware which are the navigation sensors (with a certain level of hardware redundancy for each of them), and of an on-board software that manages, monitors and performs consistency checks to detect and isolate potential sensor failures. The GMS relies on six kinds of navigation sensors, used during various phases of the mission : the gyrometers assembly (GYRA), the accelerometers assembly (ACCA), the star trackers (STR), the GPS receivers, the telegoniometers (TGM) and the videometers (VDM), the last two being used for the final rendezvous phase. The GMS function is developed by EADS Space Transportation together with other industrial partners: EADS Astrium, EADS Sodern, Laben and Dasa Jena Optronik.

Extraglottic airway devices: technology update

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Sharma B

2017-08-01

Full Text Available Bimla Sharma, Chand Sahai, Jayashree Sood Department of Anaesthesiology, Pain and Perioperative Medicine, Sir Ganga Ram Hospital, New Delhi, India Abstract: Extraglottic airway devices (EADs have revolutionized the field of airway management. The invention of the laryngeal mask airway was a game changer, and since then, there have been several innovations to improve the EADs in design, functionality, safety and construction material. These have ranged from changes in the shape of the mask, number of cuffs and material used, like rubber, polyvinylchloride and latex. Phthalates, which were added to the construction material in order to increase device flexibility, were later omitted when this chemical was found to have serious adverse reproductive outcomes. The various designs brought out by numerous companies manufacturing EADs resulted in the addition of several devices to the airway market. These airway devices were put to use, many of them with inadequate or no evidence base regarding their efficacy and safety. To reduce the possibility of compromising the safety of the patient, the Difficult Airway Society (DAS formed the Airway Device Evaluation Project Team (ADEPT to strengthen the evidence base for airway equipment and vet the new extraglottic devices. A preuse careful analysis of the design and structure may help in better understanding of the functionality of a particular device. In the meantime, the search for the ideal EAD continues. Keywords: extraglottic airway devices, laryngeal mask airway, other extraglottic airway devices, safety, technology update

Acute effect of ambient air pollution on heart failure in Guangzhou, China.

Science.gov (United States)

Yang, Changyuan; Chen, Ailan; Chen, Renjie; Qi, Yongqing; Ye, Jianjun; Li, Shuangming; Li, Wanglin; Liang, Zijing; Liang, Qing; Guo, Duanqiang; Kan, Haidong; Chen, Xinyu

2014-12-15

Heart failure (HF) is a global public health problem of increasing importance. The association between acute exposure to air pollution and HF has been well established in developed countries, but little evidence was available in developing countries where air pollution levels were much higher. We conducted a time-series study to investigate the short-term association between air pollution and overall emergency ambulance dispatches (EAD) due to HF in Guangzhou, China. Daily data of EAD due to HF from 1 January 2008 to 31 December 2012 were obtained from Guangzhou Emergency Center. We applied the over-dispersed Poisson generalized addictive model to analyze the associations after controlling for the seasonality, day of the week and weather conditions. We identified a total of 3375 EAD for HF. A 10-μg/m(3) increase in the present-day concentrations of particulate matter with an aerodynamic diameter of less than 10 μm, sulfur dioxide and nitrogen dioxide corresponded to increases of 3.54% [95% confidence interval (CI): 1.35%, 5.74%], 5.29% (95% CI: 2.28%, 8.30%) and 4.34% (95% CI: 1.71%, 6.97%) in daily EAD for HF, respectively. The effects of air pollution on acute HF were restricted on the concurrent day and in the cool seasons. Our results provided the first population-based evidence in Mainland China that outdoor air pollution could trigger the exacerbation of HF. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Aspectos discursivos sobre/no ensino-aprendizagem de língua inglesa e na formação de professores em um curso EaD

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Cristiane Carvalho de Paula Brito

2015-05-01

Full Text Available Resumo Este trabalho visa apresentar resultados parciais de uma investigação sobre o ensino-aprendizagem de língua inglesa (LI e formação de professores, desenvolvida em um curso de graduação em língua e literatura inglesas, em uma universidade pública mineira. À luz dos pressupostos teórico-metodológicos da Análise do Discurso francesa em interface com os estudos em Linguística Aplicada, propomo-nos a discutir: (i o desenho do curso e materiais e seu possível impacto na formação dos licenciandos; (ii as representações por eles construídas acerca dos processos de ensino-aprendizagem de LI a distância; e (iii as práticas de aprendizagem que têm sido desenvolvidas no curso. As análises apontam que a relação dos sujeitos com a LI vai se delineando e se ressignificando ao longo do curso e que as práticas de linguagem desenvolvidas no contexto das novas tecnologias se dão em processos de descontinuidade e não de uma suposta ruptura, trazendo à tona a relação singular que os sujeitos estabelecem com a língua que aprendem-ensinam. Palavras-chave: EaD, ensino-aprendizagem de língua inglesa, discurso, formação de professores.   Discursive aspects about/in English teaching-learning and teacher education in a distance course Abstract This paper presents partial results of a research on the teaching and learning of English language (EL and teacher education, developed in an undergraduate course in English language and English language literature at a public university in the State of Minas Gerais, Brazil. In light of the theoretical and methodological assumptions of the French Discourse Analysis in its interface with studies in Applied Linguistics, we propose to discuss: (i the course design and materials and their possible impact on the development of the undergraduates; (ii the representations of the processes of teaching and learning the EL at a distance as built by them; and (iii the learning practices that have been

A Macro Analysis of DoD Logistics Systems. Volume 2. Structure and Analysis of the Air Force Logistics System

Science.gov (United States)

1977-09-01

performance measures discussed earlier is the "Engine Actuarial Data Summary" (EADS) (AFLC Form 992), compiled from D024F actuarial data. EADS is...3.2,452.3 PlyLWn M"Is, 404.670 432.603 408,553. 413.940 PMiSMA-00023 AF asm -haiw pua-flywa hma tread =100% PTtU94411 "Weul ’A101) 16,839.6 1.6,308.0...Engine Actuarial Data Summary. ENORS - 2ngine Not Operationally Ready, Supply. EOQ Items - Economic Order Quantity Items; i.e., expense-type items, not

Educação Superior à Distância: a qualidade passa pela avaliação

OpenAIRE

Castanheira, Nelson Pereira; Centro Integrado de Educação, Ciência e Tecnologia

2012-01-01

Na última década, houve um aumento na oferta de vagas no ensino superior no Brasil,  com a implantação de cursos superiores na modalidade de educação a distância (EaD). Cabe frisar o desenvolvimento de tecnologias educacionais como ferramenta didática e operacional neste processo. Assim, este artigo versa sobre as transformações que ocorreram e as perspectivas futuras sobre a EaD. Os dados a serem apresentados vislumbram o crescimento desta modalidade de ensino, que vêm permitindo às Institui...

Mulheres e forma??o docente em tempos de tic: narrativas de experi?ncias de inclus?o, compet?ncias e empoderamento na UFPB virtual

OpenAIRE

Barbosa, Rita Cristiana

2015-01-01

As experi?ncias de Educa??o ? Dist?ncia (EaD) desenvolvidas no Brasil t?m como objetivo principal formar professores(as) que atuam no magist?rio sem a forma??o superior e tamb?m atingir a grande demanda de pessoas que n?o t?m acesso ? educa??o superior, situa??o agravada em lugares distantes dos grandes centros e nos Estados mais pobres do pa?s. Assim, os cursos EaD de forma??o docente contam com alunado composto majoritariamente por mulheres trabalhadoras com mais de 30 anos. Dentre as vanta...

Dewatering of sludges

International Nuclear Information System (INIS)

Bode, P.

1984-01-01

A filter rig has been designed and built. Simulated magnox and alumino ferric hydroxide sludges have been successfully filtered on this equipment and both types of sludge produced a clear filtrate and a cake. The flow rates were low. The cake often partially remained adhered to the filter membrane instead of dropping clear during the filter cleaning cycle. This filtration technique can only be used on sludges which form a non-binding cake. Permeability of the membrane can be altered by stretching. Irradiation of the membrane showed that it should withstand 20 to 50 M.rads. (author)

Design of an Acoustic Probe to Measure Otoacoustic Emissions Below 0.5 kHz

DEFF Research Database (Denmark)

Christensen, Anders Tornvig; Ordoñez, Rodrigo; Hammershøi, Dorte

2015-01-01

Our ability to hear is reflected in low-level acoustic signals emitted from the ear. These otoacoustic emissions (OAEs) can be measured with an acoustic probe assembly coupling one or more small loudspeakers and microphones into the sealed ear canal. The electroacoustic instrumentation of commerc...

Finite element modeling of the 1-D piezoceramic ultrasound array inter-element cross-coupling

NARCIS (Netherlands)

State, M.; Ledoux, L.; Vosse, van de F.N.

2008-01-01

sponsible for undesired behavior in radiation field patterns and electroacoustic response of the ultrasound transducers for medical imaging. This undesired behavior is ultimately impairing the end echographic image quality [1,2]. The aim of our research is to study the influence of the dicing depth,

Radioactive waste processing device

International Nuclear Information System (INIS)

Inaguma, Masahiko; Takahara, Nobuaki; Hara, Satomi.

1996-01-01

In a processing device for filtering laundry liquid wastes and shower drains incorporated with radioactive materials, a fiber filtration device is disposed and an activated carbon filtration device is also disposed subsequent to the fiber filtration device. In addition, a centrifugal dewatering device is disposed for dewatering spent granular activated carbon in the activated carbon filtration device, and a minute filtering device is disposed for filtering the separated dewatering liquid. Filtrates filtered by the minute filtration device are recovered in a collecting tank. Namely, at first, suspended solid materials in laundry liquid wastes and shower drains are captured, and then, ingredients concerning COD are adsorbed in the activated carbon filtration device. The radioactive liquid wastes of spent granular activated carbon in the activated carbon filtration device are reduced by dewatering them by the centrifugal dewatering device, and then the granular activated carbon is subjected to an additional processing. Further, it is separated by filtration using the minute filtration device and removed as cakes. Since the filtrates are recovered to the collecting tank and filtered again, the water quality of the drains is not degraded. (N.H.)

Pharmaceutical and personal care products in tile drainage following surface spreading and injection of dewatered municipal biosolids to an agricultural field.

Science.gov (United States)

Edwards, M; Topp, E; Metcalfe, C D; Li, H; Gottschall, N; Bolton, P; Curnoe, W; Payne, M; Beck, A; Kleywegt, S; Lapen, D R

2009-07-01

Land application of municipal biosolids can be a source of environmental contamination by pharmaceutical and personal care products (PPCPs). This study examined PPCP concentrations/temporally discrete mass loads in agricultural tile drainage systems where two applications of biosolids had previously taken place. The field plots received liquid municipal biosolids (LMB) in the fall of 2005 at an application rate of approximately 93,500 L ha (-1), and a second land application was conducted using dewatered municipal biosolids (DMB) applied at a rate of approximately 8Mg dw ha (-1) in the summer of 2006 [corrected].The DMB land application treatments consisted of direct injection (DI) of the DMB beneath the soil surface at a nominal depth of approximately 0.11 m, and surface spreading (SS) plus subsequent tillage incorporation of DMB in the topsoil (approximately 0.10 m depth). The PPCPs examined included eight pharmaceuticals (acetaminophen, fluoxetine, ibuprofen, gemfibrozil, naproxen, carbamazepine, atenolol, sulfamethoxazole), the nicotine metabolite cotinine, and two antibacterial personal care products triclosan and triclocarban. Residues of naproxen, cotinine, atenolol and triclosan originating from the fall 2005 LMB application were detected in tile water nearly nine months after application (triclocarban was not measured in 2005). There were no significant differences (p>0.05) in PPCP mass loads among the two DMB land application treatments (i.e., SS vs. DI); although, average PPCP mass loads late in the study season (>100 days after application) were consistently higher for the DI treatment relative to the SS treatment. While the concentration of triclosan (approximately 14,000 ng g(-1) dw) in DMB was about twice that of triclocarban (approximately 8000 ng g(-1) dw), the average tile water concentrations for triclosan were much higher (43+/-5 ng L(-1)) than they were for triclocarban (0.73+/-0.14 ng L(-1)). Triclosan concentrations (maximum observed in 2006

Crosswalking EAD: Collaboration in Archival Description

Directory of Open Access Journals (Sweden)

Amy McCrory

2005-09-01

Full Text Available Different library departments must work together, both formally and informally, in implementing encoded archival description and in repackaging descriptive information about archival collections to other formats, particularly machine-readable cataloging. The authors, one a technical services librarian and the other a special collections archivist, describe their experiences collaborating in these processes at The Ohio State University. Although other institutions may differ in their organizational structure, the authors hope to provide technical guidance, as well as a model of collaboration between archivists and technical services personnel. Careful dialogue and planning are essential to transcend the traditional divide between archival and library descriptive practices and systems.

77 FR 10809 - Endangered and Threatened Wildlife and Plants; Endangered Status and Designations of Critical...

Science.gov (United States)

2012-02-23

... streams into intermittent streams, large reservoirs, or dewatered channels, thus eliminating suitable... either dewater channels or reduce flows to low levels or pools within an active channel therefore... River has undergone sedimentation, riparian habitat degradation, and extensive water diversion and at...

Anti-Collision Function Design and Performances of the CNES Formation Flying Experiment on the PRISMA Mission

Science.gov (United States)

Cayeux, P.; Raballand, F.; Borde, J.; Berges, J.-C.; Meyssignac, B.

2007-01-01

Within the framework of a partnership agreement, EADS ASTRIUM has worked since June 2006 for the CNES formation flying experiment on the PRISMA mission. EADS ASTRIUM is responsible for the anti-collision function. This responsibility covers the design and the development of the function as a Matlab/Simulink library, as well as its functional validation and performance assessment. PRISMA is a technology in-orbit testbed mission from the Swedish National Space Board, mainly devoted to formation flying demonstration. PRISMA is made of two micro-satellites that will be launched in 2009 on a quasi-circular SSO at about 700 km of altitude. The CNES FFIORD experiment embedded on PRISMA aims at flight validating an FFRF sensor designed for formation control, and assessing its performances, in preparation to future formation flying missions such as Simbol X; FFIORD aims as well at validating various typical autonomous rendezvous and formation guidance and control algorithms. This paper presents the principles of the collision avoidance function developed by EADS ASTRIUM for FFIORD; three kinds of maneuvers were implemented and are presented in this paper with their performances.

A inserção da educação a distância no ensino superior do Brasil: diretrizes e marcos regulatórios

Directory of Open Access Journals (Sweden)

Stella Cecilia Duarte Segenreich

2012-04-01

Full Text Available O artigo objetiva fazer uma reflexão críticasobre os marcos regulatórios que nortearama institucionalização da Educação Superior aDistância no Brasil (EAD, tomando como referência50 (cinquenta documentos analisadospara a pesquisa Expansão do ensino superiorpós – LDB/96. Verificou-se que a necessidadede sistematização da EAD, legitimadapor essa lei, encontrava-se nas diretrizes dosorganismos internacionais como estratégiade expansão da educação superior, e queas primeiras iniciativas do governo brasileiroestavam associadas à utilização das tecnologiasna educação. A análise contextualizadados marcos regulatórios, evidenciou, inicialmente,a explosão quantitativa e massificadada EAD, sem que o Estado estivesse instrumentalizadopara sua regulação efetiva. Apartir de 2005, novos atos regulatórios e acriação da Universidade Aberta do Brasilprocuram manter essa expansão sem perderde vista a qualidade.

Early experience with percutaneous cryoablation of extra-abdominal desmoid tumors

Energy Technology Data Exchange (ETDEWEB)

Kujak, Jennifer L.; Liu, Patrick T. [Mayo Clinic Arizona, Department of Radiology, Phoenix, AZ (United States); Johnson, Geoffrey B.; Callstrom, Matthew R. [Mayo Clinic Rochester, Department of Radiology, Rochester, MN (United States)

2010-02-15

Surgical resection, radiation therapy and chemotherapy are all accepted as standard treatments for extra-abdominal desmoid (EAD) tumors, but their effectiveness has been limited by frequent local recurrence. The purpose of this article is to describe our early experiences with using percutaneous cryoablation for local control of extra-abdominal desmoid tumors in five patients whose tumors had failed to respond to standard therapy. In a retrospective search of our institution's radiology database for patients who had undergone percutaneous cryoablation for treatment of EAD tumors between June 2004 and July 2007, we identified five patients (three female and two male). No patients were excluded from this review. Three of these patients had been referred for cryoablation for local tumor control, and two had been referred for palliation of inoperable tumors. The age range of the patients at the time of cryoablation was 9-41 years. The treated EAD tumors were located in the neck, shoulders and trunk and ranged in size from 3.0 cm to 10.0 cm. Medical records were reviewed for short-term and long-term follow-up, and patients were contacted for additional follow-up. Patients were asked to rate their pain as absent, mild, moderate or severe, and to compare it with their levels before cryoablation, describing it as improved, unchanged or worsened. Radiology records were reviewed to follow the size of the EAD tumors before and after cryotherapy. For the three patients referred for local control of EAD tumors, complete tumor coverage with the ablation zones was achieved. Two of these patients, with masses 3.0 cm and 4.9 cm in diameter, reported complete absence of pain at both short-term and long-term follow-up at 13 months and 49 months. Their tumors had completely resolved on long-term imaging follow-up at 19 months and 43 months. The third patient, with a 6.1 cm mass, reported improved mild pain at 6 months, and imaging showed a moderate decrease of tumor size. For the

GILDED BITCH

DEFF Research Database (Denmark)

Meldgaard, Morten; jørgensen, peter

2014-01-01

's previous works, electro-acoustic compositions subject to heavy computer processing, the most notable departure on Gold Beach is the prominent use of unprocessed acoustic instruments, including double bass, violin, clarinet and saxophone. The framework to Gold Beach was created by Jørgensen and his group...

Three-dimensional space charge distribution measurement in electron beam irradiated PMMA

International Nuclear Information System (INIS)

Imaizumi, Yoichi; Suzuki, Ken; Tanaka, Yasuhiro; Takada, Tatsuo

1996-01-01

The localized space charge distribution in electron beam irradiated PMMA was investigated using pulsed electroacoustic method. Using a conventional space charge measurement system, the distribution only in the depth direction (Z) can be measured assuming the charges distributed uniformly in the horizontal (X-Y) plane. However, it is difficult to measure the distribution of space charge accumulated in small area. Therefore, we have developed the new system to measure the three-dimensional space charge distribution using pulsed electroacoustic method. The system has a small electrode with a diameter of 1mm and a motor-drive X-Y stage to move the sample. Using the data measured at many points, the three-dimensional distribution were obtained. To estimate the system performance, the electron beam irradiated PMMA was used. The electron beam was irradiated from transmission electron microscope (TEM). The depth of injected electron was controlled using the various metal masks. The measurement results were compared with theoretically calculated values of electron range. (author)

Case studies in live electronic music preservation : Recasting Jorge Peixinho's Harmónicos (1967-1986 and Sax-Blue (1984-1992

Directory of Open Access Journals (Sweden)

António de Sousa Dias

2009-05-01

Full Text Available We present two examples of technology transfer from analogical to digital systems, in two works of live electroacoustic music by the Portuguese composer Jorge Peixinho (1940-1995, Harmónicos (1967 and Sax-Blue (1982. These works require the use of analogue technology that has become obsolete or difficult to access by the average performer. We think that migration from electronics to software, also referred as recast represents a necessary step to preserve live electroacoustic music. However, this process can pose multiple questions as it also relies on aesthetic considerations. In this case, we put on a considerable effort into understanding both the composer's intentions and the equipment operating mode and we think the solutions proposed are adequate to perform both works. Finally, we discuss some of the questions, solutions and limitations that arose with these recasts and how they can contribute to the sustainability problem concerning these works.

The Ecology and Environmental Impacts of Hydrilla

Science.gov (United States)

1992-10-15

in the dewatered areas. The drawdown also encouraged the germination of waterhyacinth seeds in the dewatered areas. Plant Analysis The productivity of...controls hydrilla in most situations. Sonar is the DowElanco registered trademark for products containing the active ingredient fluridone . Sonar aquatic

Role of sarcoplasmic reticulum calcium in development of secondary calcium rise and early afterdepolarizations in long QT syndrome rabbit model.

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Po-Cheng Chang

Full Text Available L-type calcium current reactivation plays an important role in development of early afterdepolarizations (EADs and torsades de pointes (TdP. Secondary intracellular calcium (Cai rise is associated with initiation of EADs.To test whether inhibition of sarcoplasmic reticulum (SR Ca2+ cycling suppresses secondary Cai rise and genesis of EADs.Langendorff perfusion and dual voltage and Cai optical mapping were conducted in 10 rabbit hearts. Atrioventricular block (AVB was created by radiofrequency ablation. After baseline studies, E4031, SR Ca2+ cycling inhibitors (ryanodine plus thapsigargin and nifedipine were then administrated subsequently, and the protocols were repeated.At baseline, there was no spontaneous or pacing-induced TdP. After E4031 administration, action potential duration (APD was significantly prolonged and the amplitude of secondary Cai rise was enhanced, and 7 (70% rabbits developed spontaneous or pacing-induced TdP. In the presence of ryanodine plus thapsigargin, TdP inducibility was significantly reduced (2 hearts, 20%, p = 0.03. Although APD was significantly prolonged (from 298 ± 30 ms to 457 ± 75 ms at pacing cycle length of 1000 m, p = 0.007 by ryanodine plus thapsigargin, the secondary Cai rise was suppressed (from 8.8 ± 2.6% to 1.2 ± 0.9%, p = 0.02. Nifedipine inhibited TdP inducibility in all rabbit hearts.In this AVB and long QT rabbit model, inhibition of SR Ca2+ cycyling reduces the inducibility of TdP. The mechanism might be suppression of secondary Cai rise and genesis of EADs.

O valor das competências docentes no ensino da Administração

Directory of Open Access Journals (Sweden)

Marcos Roberto Kühl

2013-12-01

Full Text Available Considerando a expansão do ensino superior brasileiro, atualmente focando na Educação a Distância (EaD e a consequente pressão sobre a formação docente, o objetivo neste estudo foi analisar a percepção de discentes da EaD quanto às competências docentes. Buscou-se responder à questão: Quais competências docentes são consideradas mais relevantes na opinião de discentes do Ensino a Distância? Para tanto, foi realizado um estudo descritivo, fazendo uso da técnica de levantamento, por meio de questionário estruturado, realizando uma Análise Fatorial Exploratória, por meio do software SPSS. Os resultados indicaram a Clareza como a variável com maior média e a Experiência Prática em atividade desvinculada às disciplinas ministradas pelo docente com menor média. Constatou-se ainda que todas as cinco variáveis que compõem o construto Postura tiveram médias altas. Por fim, foram identificadas as competências percebidas pelos discentes de EaD como as mais relevantes na seguinte ordem: Postura, Didática, Relacionamento, Conhecimento e Experiência. Essa classificação difere em vários pontos daquelas identificadas na literatura, diferenciação que pode ser analisada, dentre outros aspectos, como resultado da expressão das percepções dos alunos da EaD, em contraponto às de alunos presenciais.

APPLICATION OF ESSENTIAL OILS EXTRACTED FROM PEELS OF ORANGES AS A PARTIAL SUBSTITUTE OF FLOCCULANT

Directory of Open Access Journals (Sweden)

Anna Kowalczyk

2016-05-01

Full Text Available The study attempts to determine the optimum conditions of the process of mechanical dewatering of municipal sewage sludge and reduction of odours emitted during this process. The process of dewatering of municipal sewage sludge was carried out using laboratory sedimentation centrifuge of MPW-350 type. Municipal sewage sludge stabilized during anaerobic digestion, taken from Wastewater Treatment Plant Jamno. The dewatering process was aided by cationic flocculant Praestol 855BS of real solution concentration 0.3% and essential oil from orange, which was extracted from orange peels in the process of steam distillation. Constant parameters of dewatering process were: pH, temperature, colour, texture, smell, water content and dry matter content. Independent variables of dewatering process were: centrifugation time (in the range 1–10 min, centrifugation speed (in the range 1000–3000 rotations/min and dose of mixture of flocculant Praestol 855BS (79% + essential oil of orange (21% in the range 0–48 ml/dm3. Water content in the sludge after the process, dry matter content in the effluent and the duration of the smell of oil in the sediment were determined. Studies showed that the essential oil from orange may be used as a partial substitute of flocculant Praestol 855BS in the process of centrifugal sedimentation. Essential oil of orange significantly reduces unpleasant odours which are emitted from sludge during mechanical dewatering. Simultaneous application of both reagents, ie. flocculant Praestol 855BS 79%, and essential oil of orange 21% of volume is recommended.

Environmental and economic life cycle assessment for sewage sludge treatment processes in Japan.

Science.gov (United States)

Hong, Jinglan; Hong, Jingmin; Otaki, Masahiro; Jolliet, Olivier

2009-02-01

Life cycle assessment for sewage sludge treatment was carried out by estimating the environmental and economic impacts of the six alternative scenarios most often used in Japan: dewatering, composting, drying, incineration, incinerated ash melting and dewatered sludge melting, each with or without digestion. Three end-of-life treatments were also studied: landfilling, agricultural application and building material application. The results demonstrate that sewage sludge digestion can reduce the environmental load and cost through reduced dry matter volume. The global warming potential (GWP) generated from incineration and melting processes can be significantly reduced through the reuse of waste heat for electricity and/or heat generation. Equipment production in scenarios except dewatering has an important effect on GWP, whereas the contribution of construction is negligible. In addition, the results show that the dewatering scenario has the highest impact on land use and cost, the drying scenario has the highest impact on GWP and acidification, and the incinerated ash melting scenario has the highest impact on human toxicity due to re-emissions of heavy metals from incinerated ash in the melting unit process. On the contrary, the dewatering, composting and incineration scenarios generate the lowest impact on human toxicity, land use and acidification, respectively, and the incinerated ash melting scenario has the lowest impact on GWP and cost. Heavy metals released from atmospheric effluents generated the highest human toxicity impact, with the effect of dioxin emissions being significantly lower. This study proved that the dewatered sludge melting scenario is an environmentally optimal and economically affordable method.

EDUCAÇÃO A DISTÂNCIA EM FOCO: UM ESTUDO SOBRE A PRODUÇÃO CIENTÍFICA BRASILEIRA

OpenAIRE

SILVA, MARIANA PAIVA DAMASCENO; MELO, MARLENE CATARINA DE OLIVEIRA LOPES; MUYLDER, CRISTIANA FERNANDES DE

2015-01-01

RESUMOA educação a distância (EaD) vem se revelando como uma significativa tendência na esfera educacional, principalmente na educação superior. A modalidade já não é novidade no mundo educacional, uma vez que os primeiros registros de sua utilização foram identificados em 1728, por meio de um curso por correspondência na cidade de Boston, nos Estados Unidos. Contudo, na atualidade, a palavra que se instala no auge da EaD é “interação”, que se torna possível mediante as tecnologias de comunic...

A percepção dos docentes frente a Educação a Distância no Stricto Sensu

OpenAIRE

Iris Linhares Pimenta; César Augusto Barreto Silva

2011-01-01

A Educação à distância (EAD) apresenta-se atualmente como um elemento de auxílio à democratização do ensino em todo o mundo. No Brasil, a interiorização da oferta do ensino superior carece de soluções inovadoras e neste cenário a EAD contribui cada vez mais com a ampliação e disponibilidade de elementos que possibilitam o alcance do conhecimento Este trabalho utilizou uma pesquisa exploratória, o universo de pesquisa foram catorze professores, onde a amostra por conveniência de cinco entrevis...

T-Learning: limites e possibilidades em televisão digital interativa

OpenAIRE

Caram, Nirave Reigota [UNESP

2012-01-01

A presente dissertação tem como objetivo investigar os limites e possibilidades do T-learning em Televisão Digital Interativa. O foco é o ensino a distância (EaD) para obtenção de educação formal, ou seja, cursos EaD resultem em certificação reconhecida. O trabalho recupera algumas iniciativas que enfrentam esse desafio e discute as novas possibilidades que se abrem com a Televisão Digital, a partir da interatividade. Neste cenário, é necessário pensar como os cursos já existentes podem migra...

Deployment of Lightweight Shock Mitigating Boat Manufacturing Innovation

Science.gov (United States)

2012-12-21

hull and deck of the 11M prototype with the forward hatches temporally secured. Lift hardware was installed. The craft was loaded per the figure...35.9262 25.8100- 25.8100 36.0443 34.3043 l- EAD Wf.IG G (Pi’-\\ A r IMJ<HEAO WING E (P) r !MJ<HEAOWING O(P) ul lll ld II lll rnr Il l II I llll Il l...ii ~ "’ 57 11M- Hull Drawings – Fiberglass Design / ?--/ - ~ L 10 1&116" ______..j_j DETAIL B-50 BU~ EAD WING A OET AIL C-50 BULKHEAD

Evaluation of energy consumption during aerobic sewage sludge treatment in dairy wastewater treatment plant.

Science.gov (United States)

Dąbrowski, Wojciech; Żyłka, Radosław; Malinowski, Paweł

2017-02-01

The subject of the research conducted in an operating dairy wastewater treatment plant (WWTP) was to examine electric energy consumption during sewage sludge treatment. The excess sewage sludge was aerobically stabilized and dewatered with a screw press. Organic matter varied from 48% to 56% in sludge after stabilization and dewatering. It proves that sludge was properly stabilized and it was possible to apply it as a fertilizer. Measurement factors for electric energy consumption for mechanically dewatered sewage sludge were determined, which ranged between 0.94 and 1.5 kWhm -3 with the average value at 1.17 kWhm -3 . The shares of devices used for sludge dewatering and aerobic stabilization in the total energy consumption of the plant were also established, which were 3% and 25% respectively. A model of energy consumption during sewage sludge treatment was estimated according to experimental data. Two models were applied: linear regression for dewatering process and segmented linear regression for aerobic stabilization. The segmented linear regression model was also applied to total energy consumption during sewage sludge treatment in the examined dairy WWTP. The research constitutes an introduction for further studies on defining a mathematical model used to optimize electric energy consumption by dairy WWTPs. Copyright © 2016 Elsevier Inc. All rights reserved.

Electro-acoustic shock waves in dusty plasmas

International Nuclear Information System (INIS)

Mamun, A.A.; Rahman, A.

2005-10-01

A rigorous theoretical investigation has been made of electro- acoustic [particularly, dust-ion acoustic (DIA) and dust-acoustic (DA)] shock waves in unmagnetized dusty plasmas. The reductive perturbation method has been employed for the study of the small but finite amplitude DIA and DA shock waves. It has been reported that the dust grain charge fluctuation can be one of the candidates for the source of dissipation, and can be responsible for the formation of DIA shock waves in an unmagnetized dusty plasma with static charged dust particles. It has also been reported that the strong co-relation among dust particles can be one of the candidates for the source of dissipation, and can be responsible for the formation of DA shock waves in an unmagnetized strongly coupled dusty plasma. The basic features and the underlying physics of DIA and DA shock waves, which are relevant to space and laboratory dusty plasmas, are briefly discussed. (author)

Electro-acoustic solitary waves in dusty plasmas

International Nuclear Information System (INIS)

Mamun, A.A.; Sayed, F.

2005-10-01

present a rigorous theoretical investigation of electro- acoustic [particularly, dust-ion acoustic (DIA) and dust-acoustic (DA)] solitary waves in dusty plasmas. We employ the reductive perturbation method for small but finite amplitude solitary waves as well as the pseudo-potential approach for arbitrary amplitude ones. We also analyze the effects of non-planar geometry and dust charge fluctuations on both DIA and DA solitary waves, the effect of finite ion-temperature on DIA solitary waves, and the effects of dust-fluid temperature and non-isothermal ion distributions on DA solitary waves. It has been reported that these effects do not only significantly modify the basic features of DIA or DA solitary waves, but also introduce some important new features. The basic features and the underlying physics of DIA and DA solitary waves, which are relevant to space and laboratory dusty plasmas, are briefly discussed. (author)

Electro-acoustic coupling in a plasma gas

OpenAIRE

Sutton, Yvonne

2011-01-01

Sound emission using an ionised medium has been the subject of research since the beginning of the 20th century. The mechanism involves modulation at an audio frequency of an electrically sustained plasma discharge. In a similar effect to lightning, the charged particles in the plasma respond to the varying energy input. With this comes gas heating, molecular excitation, light emission from relaxation of excited molecular states and acoustic emission resulting from thermal expansion within, a...

Assessment of COTS IR image simulation tools for ATR development

Science.gov (United States)

Seidel, Heiko; Stahl, Christoph; Bjerkeli, Frode; Skaaren-Fystro, Paal

2005-05-01

Following the tendency of increased use of imaging sensors in military aircraft, future fighter pilots will need onboard artificial intelligence e.g. ATR for aiding them in image interpretation and target designation. The European Aeronautic Defence and Space Company (EADS) in Germany has developed an advanced method for automatic target recognition (ATR) which is based on adaptive neural networks. This ATR method can assist the crew of military aircraft like the Eurofighter in sensor image monitoring and thereby reduce the workload in the cockpit and increase the mission efficiency. The EADS ATR approach can be adapted for imagery of visual, infrared and SAR sensors because of the training-based classifiers of the ATR method. For the optimal adaptation of these classifiers they have to be trained with appropriate and sufficient image data. The training images must show the target objects from different aspect angles, ranges, environmental conditions, etc. Incomplete training sets lead to a degradation of classifier performance. Additionally, ground truth information i.e. scenario conditions like class type and position of targets is necessary for the optimal adaptation of the ATR method. In Summer 2003, EADS started a cooperation with Kongsberg Defence & Aerospace (KDA) from Norway. The EADS/KDA approach is to provide additional image data sets for training-based ATR through IR image simulation. The joint study aims to investigate the benefits of enhancing incomplete training sets for classifier adaptation by simulated synthetic imagery. EADS/KDA identified the requirements of a commercial-off-the-shelf IR simulation tool capable of delivering appropriate synthetic imagery for ATR development. A market study of available IR simulation tools and suppliers was performed. After that the most promising tool was benchmarked according to several criteria e.g. thermal emission model, sensor model, targets model, non-radiometric image features etc., resulting in a

Technical report on treatment of radioactive slurry liquid waste

International Nuclear Information System (INIS)

Jeong, Gyeong Hwan; Jo, Eun Sung; Park, Seung Kook; Jung, Ki Jung

1999-06-01

By literature survey, this report deals with the technology on typical pre-treatment and filtration of radioactive slurry liquid waste, produced during the operation of TRIGA Mark-II, III research reactor, and produced during the decommission/decontamination of TRIGA Mark-II, III research reactor. It is reviewed pre-treatment procedure, both physical and chemical that optimise the dewatering characteristics, and also surveyed types of dewatering devices based on centrifuges, vacuum and pressure filters with particular reference to various combined field approaches using two or more complementary driving forces to achieve better performance. Dewatering operations and devises on filtration of radioactive slurry liquid waste are also analysed. (author)

Novel Two-Step Classifier for Torsades de Pointes Risk Stratification from Direct Features

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Jaimit Parikh

2017-11-01

Full Text Available While pre-clinical Torsades de Pointes (TdP risk classifiers had initially been based on drug-induced block of hERG potassium channels, it is now well established that improved risk prediction can be achieved by considering block of non-hERG ion channels. The current multi-channel TdP classifiers can be categorized into two classes. First, the classifiers that take as input the values of drug-induced block of ion channels (direct features. Second, the classifiers that are built on features extracted from output of the drug-induced multi-channel blockage simulations in the in-silico models (derived features. The classifiers built on derived features have thus far not consistently provided increased prediction accuracies, and hence casts doubt on the value of such approaches given the cost of including biophysical detail. Here, we propose a new two-step method for TdP risk classification, referred to as Multi-Channel Blockage at Early After Depolarization (MCB@EAD. In the first step, we classified the compound that produced insufficient hERG block as non-torsadogenic. In the second step, the role of non-hERG channels to modulate TdP risk are considered by constructing classifiers based on direct or derived features at critical hERG block concentrations that generates EADs in the computational cardiac cell models. MCB@EAD provides comparable or superior TdP risk classification of the drugs from the direct features in tests against published methods. TdP risk for the drugs highly correlated to the propensity to generate EADs in the model. However, the derived features of the biophysical models did not improve the predictive capability for TdP risk assessment.

Processos de trabalho e de subjetivação de professores universitários de cursos de educação à distância

Directory of Open Access Journals (Sweden)

Maria Antonieta Mendes da Luz

Full Text Available Resumo Este estudo teve por objetivo analisar a relação entre processos de trabalho e processos de subjetivação na atividade do ensino docente da educação à distância (EaD. Optou-se por realizar uma pesquisa qualitativa e exploratória, que teve como procedimento o estudo de caso único e como instrumentos a observação, a pesquisa documental, o questionário e a entrevista semidirigida. Os resultados revelaram que os professores percebem as Tecnologias de Informação e Comunicação (TIC como inerentes a todas as esferas de suas vidas, ocorrendo também, um acirramento do volume de trabalho e a necessidade de eles se disciplinarem. A organização do trabalho na EaD pressupõe uma nova forma de estruturar-se, em que existe aumento do controle, o que cerceia a autonomia docente; as relações socioprofissionais mediadas pelas TIC tornam o trabalho dos professores de EaD mais solitário mas, ao mesmo tempo, requerem uma equipe multidisciplinar para executar o trabalho docente.

Effect of Film Thickness and Physical Aging on “Intrinsic” Gas Permeation Properties of Microporous Ethanoanthracene-Based Polyimides

KAUST Repository

Ma, Xiaohua

2018-01-31

Two ethanoanthracene-based dianhydrides, 9,10-dimethylethanoanthracene-2,3,6,7-tetracarboxylic anhydride (EA-DA) and its more flexible dibenzodioxane-containing derivative (EAD-DA), were synthesized from the same starting material, 9,10-dimethyl-ethanoanthracene-2,3,6,7-tetraol, and used for the preparation of bicyclic intrinsically microporous polyimides (PIM-PIs) by one-pot polycondensation reaction with 3,3′-dimethylnaphthidine (DMN). The resulting organosoluble polyimides, EA-DMN and EAD-DMN, were thermally stable up to 300 °C and had good mechanical properties with tensile strength of 55 and 63 MPa and elongation at break of 15 and 30%, respectively. EA-DMN and EAD-DMN polyimides displayed Brunauer–Emmett–Teller (BET) surface areas of 720 and 800 m2 g–1, respectively. Fresh films showed promising gas separation performance with very high gas permeabilities and moderate gas-pair selectivities, which were both strongly dependent on film thickness. The results obtained in this study shed more light on the relative importance of film thickness and physical aging on faster attainment of the “intrinsic” gas transport properties of high free volume PIM-PIs.

Terza partita. La musica nell’età della tecnica – un madrigale

OpenAIRE

Nicola Buso

2011-01-01

in the electroacoustic music field the writing grow weak; the action, the listening, the body memory come out; the writing become theatrical action in the collaborative live coding praxis over network: the technological action reveal itself like the root of language, of thought, of culture, like the essence of man, where history accomplish.

Volume reduction and encapsulation process for water containing low-level radioactive waste

International Nuclear Information System (INIS)

Fox, D.W.; Miller, G.P.; Weech, M.E.

1984-01-01

Solutions or slurries of waste material in water are dewatered and encapsulated within a polymer for disposal, comprising the operations of removing water therefrom with azeotropic mixture evaporation and encasing the dewatered waste residue in an organic polymer. The method and system disclosed are especially useful for the safe disposal of radioactive waste

Educacão a distância e inovacão tecnológica Distance education and technological innovation

Directory of Open Access Journals (Sweden)

Maria Luiza Belloni

2005-03-01

Full Text Available A crescente integração das Tecnologias de Informação e Comunicação (TIC aos processos de comunicação e educação torna necessária a concepção de novas formas de se organizar e ofertar o ensino. Neste contexto, o presente artigo aborda a educação a distância (Ead apontando para os riscos implicados em se confundir inovação técnica com inovação pedagógica e destacando a importância de se transferir o foco da discussão sobre a EaD da 'modalidade' para o 'método', da organização do ensino para os modos de ensinar e aprender. Para isso, é preciso considerar a técnica em sua dupla dimensão - objeto de estudo e ferramenta pedagógica - e a educação em seu caráter interdisciplinar. A abordagem aqui apresentada contrapõe-se à concepção tecnicista do ensino, deslocando a tecnologia do centro do processo educacional e colocando em destaque a dimensão histórica e social da educação. Acredita-se que, mais que uma forma de preencher as lacunas do sistema educacional, a EaD tende a se tornar um elemento regular dos atuais sistemas de ensino, podendo contribuir para a democratização do acesso à educação, caso se realize na perspectiva da aprendizagem aberta e de forma integrada com o ensino convencional.The growing integration of the Information and Communication Technologies with communication and educational processes requires new forms of organizing and transmitting knowledge. With this in mind, the present article examines distance education (educação a distância - EaD pointing to the risks involved in mistaking technical innovation for pedagogical innovation; and it also gives emphasis to the importance of transferring the focus of the debate on EaD from 'modality' to 'method', and from teaching organization to forms of teaching and of learning. For this purpose, we must consider the two dimensions of technique - as an object of study and as a pedagogical tool - and also the interdisciplinary character of

Educação à Distância como estratégia para a educação permanente em saúde: possibilidades e desafios Educación a la Distancia como estratégia para la educación permanente en salud: posibilidades y desafíos Distance Education as strategy for permanent education in health: possibilities and challenges

Directory of Open Access Journals (Sweden)

Marluce Alves Nunes Oliveira

2007-10-01

Full Text Available Este estudo objetivou refletir sobre a importância da Educação Permanente em Saúde (EPS na promoção do processo de mudança nos docentes da UEFS; estabelecer estratégias para a promoção da EPS e apontar as possibilidades e os desafios para a operacionalização da EAD como estratégia para a EPS. Estudo de revisão bibliográfica. O resultado aponta que a EPS é uma das estratégias para a formação do profissional através de trabalhos coletivos entre os docentes. Como possibilidade: EAD possibilita construir um novo estilo na formação. Desafios: necessidade de conhecimento para utilizar as novas tecnologias da informação e comunicação; dificuldade de acesso a estas tecnologias; escassez de tempo para desenvolver as atividades do curso. Apreendemos que a EAD apresenta nova perspectiva para EPS.Este estudio buscó reflexionar al respecto de la importancia de la Educación Permanente em Salud (EPS em la promoción del proceso de cambios em los docentes de la Universidad Estatal de Feira de Santana (UEFS; establecer estratégias para la promoción de la EPS y apuntar las posibilidades y los desafíos para la operacionalización de la Educación a la Distancia (EAD como estratégia para la EPS. Estudio de una revización bibliográfica. El resultado apunta a que la EPS és una de las estratégias para la formación del profesional por médio de trabajos colectivos entre los docentes. Como posibilidad: EAD posibilita construir um nuevo estilo em lá formación. Desafíos: necesidad de conocimiento para utilizar las nuevas tecnologíes de la información y comunicación; dificultad de acceso a estas tecnologias; poco tiempo para desarrollar las actividades del curso. Aprendimos que la EAD presenta nueva perspectiva para la EPS.The point of this study is to reflect about how important Permanent Education in Health (PEH is in the promotion of the changes process of professors of UEFS; to establish strategies to promote PEH and show the

Construção de instrumento para avaliar a acurácia diagnóstica Construcción de instrumento para evaluar la exactitud diagnóstica Development of an instrument to evaluate diagnosis accuracy

Directory of Open Access Journals (Sweden)

Fabiana Gonçalves de Oliveira Azevedo Matos

2009-12-01

Full Text Available Diagnósticos acurados são importantes para a escolha adequada de intervenções. Neste artigo relata-se pesquisa metodológica de desenvolvimento de instrumento para estimar a acurácia de diagnósticos de enfermagem a partir de dados escritos da avaliação de paciente. Elaborou-se a definição de acurácia e a construção dos itens que compõem o instrumento, submetendo-os a validação de conteúdo e teste piloto. O instrumento foi denominado Escala de Acurácia de Diagnóstico de Enfermagem - EADE e foi composto por 4 itens: Presença de pistas; Relevância da pista; Especificidade da pista e Coerência da pista. As respostas de 12 enfermeiros especialistas à aplicação da EADE aos diagnósticos de 5 casos escritos permitiram identificar valores para cada item e estimar a validade e confiabilidade da EADE.Diagnósticos precisos son importantes para la elección adecuada de las intervenciones. Este artículo se refiere al desarrollo de herramienta metodológica de investigación para estimar la precisión de los diagnósticos de enfermería apartir de datos escritos de la evaluación de paciente. Se elaboró la definición de la precisión y la construcción de los elementos que componen el instrumento, sometiéndolos a prueba del contenido y el test piloto. El instrumento fue llamado Exactitud Diagnóstica de Enfermería - EADE y estaba compuesto por 4 elementos: Presencia de pistas; Pertinencia de la pista; especificidad de la pista y la coherencia de la pista. Las respuestas de 12 enfermeros especialistas a la aplicación de EADE a los diagnósticos de 5 casos por escrito permitiran identificar los valores para cada tema y estimar la validez y la fiabilidad de EADE.Accurate diagnoses are important for choosing adequate interventions. This study reports on a methodological research that developed an instrument to estimate nursing diagnosis accuracy, based on written data from patients' assessment. A definition of accuracy was

Educação a distância em foco: um estudo sobre a produção científica brasileira.

Directory of Open Access Journals (Sweden)

Mariana Paiva Damasceno Silva

2015-08-01

Full Text Available A educação a distância (EaD vem se revelando como uma significativa tendência na esfera educacional, principalmente na educação superior. A modalidade já não é novidade no mundo educacional, uma vez que os primeiros registros de sua utilização foram identificados em 1728, por meio de um curso por correspondência na cidade de Boston, nos Estados Unidos. Contudo, na atualidade, a palavra que se instala no auge da EaD é “interação”, que se torna possível mediante as tecnologias de comunicação cada vez mais fluentes e eficazes. Hoje, já se é possível falar, inclusive, em interação em tempo real, proporcionada pelas videoconferências, por exemplo, em que pessoas, espacialmente separadas, assistem a uma aula de forma síncrona. Dessa forma, as instituições de ensino que a ofertam precisam estar atentas à melhor maneira de agir com relação a seus alunos e aos processos organizacionais. O objetivo deste estudo consiste em investigar a produção científica no campo da administração acerca do tema EaD, bem como identificar os modelos de fatores críticos de sucesso desenvolvidos em artigos científicos da área. Nesse intuito, apresentam-se os principais conceitos sobre EaD. Foram identificados e analisados todos os artigos publicados nos anais de todos os eventos organizados pela Associação Nacional de Pós--Graduação e Pesquisa em Administração (Anpad e os artigos publicados nos periódicos brasileiros da área de administração com maior pontuação (A1, A2, B1 e B2, conforme a classificação Qualis-Capes 2010, sem delimitação temporal, que abordassem questões relacionadas à EaD disponíveis em meio eletrônico. Ao final, encontraram-se 71 trabalhos científicos, cujos conteúdos foram classificados de acordo com os seguintes critérios: distribuição por periódico/evento e anual, natureza da análise, tipo de abordagem, principais técnicas de coleta de dados, fator bibliográfico e identifica

Bifunctional polymer hydrogel layers as forward osmosis draw agents for continuous production of fresh water using solar energy.

Science.gov (United States)

Razmjou, Amir; Liu, Qi; Simon, George P; Wang, Huanting

2013-11-19

The feasibility of bilayer polymer hydrogels as draw agent in forward osmosis process has been investigated. The dual-functionality hydrogels consist of a water-absorptive layer (particles of a copolymer of sodium acrylate and N-isopropylacrylamide) to provide osmotic pressure, and a dewatering layer (particles of N-isopropylacrylamide) to allow the ready release of the water absorbed during the FO drawing process at lower critical solution temperature (32 °C). The use of solar concentrated energy as the source of heat resulted in a significant increase in the dewatering rate as the temperature of dewatering layer increased to its LSCT more rapidly. Dewatering flux rose from 10 to 25 LMH when the solar concentrator increased the input energy from 0.5 to 2 kW/m(2). Thermodynamic analysis was also performed to find out the minimum energy requirement of such a bilayer hydrogel-driven FO process. This study represents a significant step forward toward the commercial implementation of hydrogel-driven FO system for continuous production of fresh water from saline water or wastewaters.

Ohtlik lend / Iain Carson

Index Scriptorium Estoniae

Carson, Iain

2006-01-01

Majanduslikesse raskustesse sattunud Euroopa tsiviillennukite tootjat Airbus, mis kuulub Prantsuse-Saksa-Hispaania emafirmale European Aeronautic Defence and Space (EADS), ootab ees natsionaliseerimine kolme riigi poolt

Terza partita. La musica nell’età della tecnica – un madrigale

Directory of Open Access Journals (Sweden)

Nicola Buso

2011-07-01

Full Text Available in the electroacoustic music field the writing grow weak; the action, the listening, the body memory come out; the writing become theatrical action in the collaborative live coding praxis over network: the technological action reveal itself like the root of language, of thought, of culture, like the essence of man, where history accomplish.

PENERAPAN ELEKTROOSMOSIS UNTUK PENGERINGAN SLUDGE DARI PENGOLAHAN LIMBAH CAIR

Directory of Open Access Journals (Sweden)

Darmawan Darmawan

2013-11-01

Full Text Available APPLICATION OF ELECTROOSMOSIS FOR DEWATERING OF SLUDGE FROM WASTE WATER TREATMENT. Wastewater treatment produces semi-solid residue (sludge that must be handled carefully during dumping and discharge to avoid polluting the environment. A low cost and easy treatment of dewatering is needed. This research aimed to apply electroosmosis technique for dewatering sludge in order to seek for parameters that can efficiently reduce water content of sludge, including range of voltage, type of electrodes, and distance between electrodes; and to determine the effect of electroosmosis processes on changes of chemical characteristics of sludge. The results showed that: (1 electroosmosis dewatering occurred on the sludge taken from waste water treatment of landfill but not on sludge from water purification plant (PDAM, (2 direct current voltage of 30 volts was the optimum voltage, (3 copper rod cathode provided electroosmosis process as good as stainless steel cathode and both were better than the woven stainless steel cathode, (4 the dewatering time to reduce 1200% (w/w water content to about 400% was about 40 hours for sludge of 2500 cm3 in volume (laboratory bench scale, (5 the anode need to reinserted gradually approaching the cathode due to current lost when the water content at the anode point reached 400% and sludge at the point shrink, and (6 some chemical elements in the sludge decreased significantly after treatment. Pengolahan limbah cair menghasilkan residu berupa bahan semi padat yang dikenal sebagai sludge. Sludge tersebut juga perlu dikelola penyimpanan dan pembuangannya agar tidak mencemari lingkungan. Salah satu pengelolaan sludge yang perlu dilakukan adalah pengeringan (dewatering. Salahsatu teknik dewatering yang mungkin diterapkan ialah teknik elektroosmosis, yaitu teknik yang memanfaatkan adanya pergerakan air pada media poros di dalam medan istrik searah. Penelitian ini bertujuan untuk mencari parameter sistem dewatering secara

EAD: ESCOLA, SAÚDE E MEIO AMBIENTE

Directory of Open Access Journals (Sweden)

Rosina Djunko Miyazaki

2016-12-01

Full Text Available Com o surgimento das novas tecnologias de informação e de comunicação, a internet tornou-se um meio propício para a difusão do conhecimento, aumentando a oferta de cursos superiores à distância. O projeto Escola, Saúde e Meio Ambiente, foi proposto pela Universidade Federal de Mato Grosso (UFMT e realizado no período de 01/05/2015 a 30/07/2016, onde foram ofertadas 400 vagas para os seguintes municípios do Estado de Mato Grosso: Aripuanã, Guarantã do Norte, Cuiabá, Barra do Bugres, Jauru, Pedra Preta, Diamantino e Sapezal. O objetivo foi estabelecer uma forma de ensino que possibilitasse a autoaprendizagem e a autonomia do aluno, por meio da mediação de recursos didáticos e proporcionar a futuros professores condições de analisar criticamente as responsabilidades com a saúde dos cidadãos nos diferentes níveis (individual, familiar, comunitário e governamental. Das 400 vagas oferecidas, 399 foram preenchidas e destes, 338 foram aprovados, 47 reprovados e 14 evadiram. Analisando os resultados obtidos, vimos a necessidade e a importância de um trabalho integrado e cooperativo, com todos tendo uma função definida em busca do objetivo proposto que é em prol da eficácia na construção do conhecimento dos cursistas.

Educação a distância: como revisar os materiais didáticos

OpenAIRE

Bezri Hermont, Arabie; Bonomo Assumpção, Solange

2010-01-01

A produção de materiais destinados à Educação a Distância (ou EaD) vem sendo alvo de atenção por diferentes instituições de ensino. Um dos aspectos implicados nessa produção é o processo de revisão de materiais que envolve tanto aspectos didáticos quanto linguísticos. Ao privilegiar uma concepção dialógica de linguagem na revisão dos materiais para a EaD, a equipe responsável por essa atividade contribui para que os autores dessas produções reavaliem seus materiais na direção da contextualiza...

Comparison of macrostickies measurement methods

Science.gov (United States)

Mahendra R. Doshi; William J. Moore; R.A. Venditti; K. Copeland; H.-M. Chang; Hans-Joachim Putz; Thierry Delagoutte; Carl Houtman; Freya Tan; Lisa Davie; Gregg Sauve; Tim Dahl; Dave Robinson

2003-01-01

Pulp containing PSA was prepared in the laboratory and blended with sticky-free pulp in four different proportions. The four pulps were then dewatered and shipped to four laboratories for the evaluation of macro stickies in terms of mm2/kg. Also, five pulp samples from specific locations in a deinking mill were dewatered and shipped to the same four laboratories....

Cutting down operating costs at sewage treatment plant through aimed application of new characterization methods; Betriebskostenreduzierung auf Klaeranlagen durch gezielte Anwendung neuer Charakterisierungsmethoden

Energy Technology Data Exchange (ETDEWEB)

Friedrich, H.; Potthoff, A. [Fraunhofer-Institut fuer Keramische Technologien und Sinterwerkstoffe (IKTS), Dresden (Germany); Friedrich, E. [Ingenieurgesellschaft fuer Wasser und Entsorgung mbH, Radebeul (Germany)

1999-07-01

Mechanical dewatering of sewage sludge is state of the art. Because of increasing cost, more stringent regulations (act on waste recycling 'Kreislaufwirtschaftsgesetz' and the technical code on municipal waste), and the lack of landfill space, expensive thermal processing techniques are gaining ever greater weight. To assure that disposal costs remain reasonable, mechanical dewatering must be more and more enhanced. The following need to be optimized and enhanced: sludge properties, conditioning, and dewatering. (orig.) [German] Klaerschlaemme maschinell zu entwaessern ist Stand der Technik. Steigende Kosten, verschaerfte Bestimmungen (Kreislaufwirtschaftsgesetz, TA Siedlungsabfall) und fehlende Deponien geben den teuren thermischen Behandlungsverfahren ein immer groesseres Gewicht. Damit die Entsorgung bezahlbar bleibt, muss immer staerker mechanisch entwaessert werden. Optimiert und verbessert werden muessen die Schlammeigenschaften, die Konditionierung und die Entwaesserung. (orig.)

Consolidation of tailings

International Nuclear Information System (INIS)

Nelson, J.D.; Wardwell, R.E.; Abt, S.R.; Staub, W.P.

1983-09-01

The integrity of cover systems placed on tailings impoundments will be affected by the potential for differential settlement of the tailings surface. Settlement of the sand fraction will occur relatively rapidly. The slimes will take longer time for consolidation and will produce greater settlement. This report reviews the phenomenon of consolidation for saturated and unsaturated tailings. The effect of load application by cover placement and the extent to which dewatering of tailings will cause consolidation are considered. In addition, the feasibility of inducing consolidation by alternative means and the potential applicability of these methods to tailings impoundments reclamation are discussed. Differential settlement of the tailings will cause tensile strain to be developed in covers. This strain could be large enough to cause cracking within a relatively brittle compacted clay. Dewatering of tailings by drainage can cause settlement even greater than that by placement of a cover material. Dewatering of the tailings would also increase the stability of the tailings surface, thereby enhancing reclamation operations. Consequently, in view of the enhanced surface stability and the fact that a portion of the differential settlement can be accomplished prior to cover placement, dewatering of tailings impoundments during operations may have benefical effects

Seasonal changes in bacterial counts and radiation-disinfection of sewage sludge

International Nuclear Information System (INIS)

Watanabe, Hiroshi; Ito, Hitoshi; Takehisa, Masaaki; Iizuka, Hiroshi.

1981-01-01

The effect of radiation on sewage sludge was investigated to disinfect it. The results obtained were as follows: 1. In either activated sludge or digested sludge dewatered by centrifugation, total bacteria and coliforms were up to 3.0 x 10 9 /g and 3.5 x 10 8 /g, respectively. In the activated sludge which was dewatered by a filter-press with calcium oxide and iron chloride, total bacteria were up to 3.0 x 10 5 /g, while coliforms were hardly detected. 2. The fraction of coliforms was somewhat more in centrifuged sludge than in raw sludge. 3. The radiosensitivity of coliforms in raw sludge differed between samples. Namely, some sludge was sterilized with 0.5 Mrad while others were not sterilized even with 1.0 Mrad. On the other hand, coliforms in dewatered sludge were sterilized with 0.5 Mrad without seasonal change, but total bacteria were more radioresistant and more than 13 Mrad was required to reduce it to an undetectable level. From these results it is concluded that the dewatered sludge should be irradiated at 0.5 Mrad to eliminate the coliforms in it. (author)

Use of the Toyota management principles for evaluation of the company’s mission

Directory of Open Access Journals (Sweden)

Jacek Selejdak

2013-04-01

Full Text Available In the paper there were described the elements of the Toyota roof. Electroacoustic products were characterized. Immaterial resources of the company were analyzed. To do so, the BOST survey, whose questionnaires were filled in by employees of the chosen enterprise, was used. Particular attention was paid to the following factors: quality, costs, lead time, work safety and personnel morale

Enhancing sewage sludge dewaterability by bioleaching approach with comparison to other physical and chemical conditioning methods.

Science.gov (United States)

Liu, Fenwu; Zhou, Jun; Wang, Dianzhan; Zhou, Lixiang

2012-01-01

The sewage sludge conditioning process is critical to improve the sludge dewaterability prior to mechanical dewatering. Traditionally, sludge is conditioned by physical or chemical approaches, mostly with the addition of inorganic or organic chemicals. Here we report that bioleaching, an efficient and economical microbial method for the removal of sludge-borne heavy metals, also plays a significant role in enhancing sludge dewaterability. The effects of bioleaching and physical or chemical approaches on sludge dewaterability were compared. The conditioning result of bioleaching by Acidithiobacillus thiooxidans and Acidithiobacillus ferrooxidans on sludge dewatering was investigated and compared with the effects of hydrothermal (121 degrees C for 2 hr), microwave (1050 W for 50 sec), ultrasonic (250 W for 2 min), and chemical conditioning (24% ferric chloride and 68% calcium oxide; dry basis). The results show that the specific resistance to filtration (SRF) or capillary suction time (CST) of sludge is decreased by 93.1% or 74.1%, respectively, after fresh sludge is conditioned by bioleaching, which is similar to chemical conditioning treatment with ferric chloride and calcium oxide but much more effective than other conditioning approaches including hydrothermal, microwave, and ultrasonic conditioning. Furthermore, after sludge dewatering, bioleached sludge filtrate contains the lowest concentrations of chroma (18 times), COD (542 mg/L), total N (TN, 300 mg/L), NH4(+)-N (208 mg/L), and total P (TP, 2 mg/L) while the hydrothermal process resulted in the highest concentration of chroma (660 times), COD (18,155 mg/L), TN (472 mg/L), NH4(+)-N (381 mg/L), and TP (191 mg/L) among these selected conditioning methods. Moreover, unlike chemical conditioning, sludge bioleaching does not result in a significant reduction of organic matter, TN, and TP in the resulting dewatered sludge cake. Therefore, considering sludge dewaterability and the chemical properties of sludge

Air Force Air Refueling: The KC-X Aircraft Acquisition Program

National Research Council Canada - National Science Library

Bolkcom, Christopher; Knight, William

2008-01-01

.... The program is expected to cost approximately $35 billion. Both Boeing and a consortium consisting of Northrop Grumman and European Aeronautic Defence and Space Company (EADS) competed for KC-X...

Enhancing the dewatering properties of sludge through aimed building-up of floc structures on the basis of detailed morphological analyses; Verbesserung der Entwaesserungseigenschaften von Schlaemmen durch den gezielten Aufbau von Flockenstrukturen auf der Basis detaillierter morphologischer Analysen

Energy Technology Data Exchange (ETDEWEB)

Nagel, M.; Ay, P. [Brandenburgische Technische Univ. Cottbus (Germany). Lehrstuhl Aufbereitungstechnik

1999-07-01

Aimed building-up of aggregates as they originate in flocculation processes, for instance in sewage and sludge treatment, have especially lately been meeting with increasing resonance: they permit to influence, inter alia, important properties (e.g., the dewatering properties) of such systems. As conventional mathematical methods for the characterization of flocs - as a basis for process optimization - are inadequate or flawed, a concept for the effective characterization of the inner getup of such structures needs to be sought. One approach is cluster analysis, which is demonstrated and discussed in the present paper by means of the evaluation of sectional views of floc structures. (orig.) [German] Der gezielte Aufbau von Aggregaten, wie sie bei Flockungsprozessen z.B. in der Abwasser- und Schlammbehandlung entstehen, findet besonders in juengerer Zeit zunehmend Beachtung, da sich damit unter anderem wichtige Eigenschaften (z.B. die Entwaesserungseigenschaften) dieser Systeme beeinflussen lassen. Da herkoemmliche mathematische Methoden zur Charakterisierung von Flocken - als Basis fuer eine Prozessoptimierung - nur unzureichend bzw. fehlerbehaftet sind, ergibt sich daraus die Notwendigkeit, nach einem Konzept zur effektiven Charakterisierung des inneren Aufbaus solcher Strukturen zu suchen. Ein Ansatz ist die Clusteranalyse, die im Beitrag durch die Auswertung von Schnittbildern von Flockenstrukturen vorgestellt und diskutiert wird. (orig.)

Educacão a distância e inovacão tecnológica

OpenAIRE

Belloni,Maria Luiza

2005-01-01

A crescente integração das Tecnologias de Informação e Comunicação (TIC) aos processos de comunicação e educação torna necessária a concepção de novas formas de se organizar e ofertar o ensino. Neste contexto, o presente artigo aborda a educação a distância (Ead) apontando para os riscos implicados em se confundir inovação técnica com inovação pedagógica e destacando a importância de se transferir o foco da discussão sobre a EaD da 'modalidade' para o 'método', da organização do ensino para o...

Hypereosinophilic Syndrome (HES)

Science.gov (United States)

... Tubes Health Information Sheet Q & A with Experts Patient Stories Social Security Disability Application Process For Kids For Teens Managing EAD at College Patient Stories For Caregivers Questions to Ask Your doctor ...

EoE (Eosinophilic Esophagitis)

Science.gov (United States)

... Tubes Health Information Sheet Q & A with Experts Patient Stories Social Security Disability Application Process For Kids For Teens Managing EAD at College Patient Stories For Caregivers Questions to Ask Your doctor ...

Essential oils and their compositions as spatial repellents for pestiferous social wasps.

Science.gov (United States)

Zhang, Qing-He; Schneidmiller, Rodney G; Hoover, Doreen R

2013-04-01

The study objectives were: (1) to field test potential repellency of common essential oils against several pestiferous social wasps (Hymenoptera: Vespidae), using attractant-baited traps; (2) to identify vespid antennally active compounds from the repellent essential oils; (3) to determine potential repellency of these electroantennographic detection (EAD) active compounds in the field. Of the 21 essential oils tested, 17 showed significant repellency on yellowjackets [mainly Vespula pensylvanica (Saussure)] and paper wasps [mainly Polistes dominulus (Christ)]: clove, pennyroyal, lemongrass, ylang ylang, spearmint, wintergreen, sage, rosemary, lavender, geranium, patchouli, citronella, Roman chamomile, thyme, fennel seed, anise and peppermint. Two essential oil mixtures - 3EO-mix (clove, geranium and lemongrass) and 4EO-mix (clove, geranium, lemongrass and rosemary) - totally blocked the attraction of vespid workers. Twenty-nine vespid antennally active compounds were identified from solid-phase microextraction (SPME) samples of 11 strongly repellent essential oils by GC-EAD/MS techniques. Among the synthetic EAD-active compounds field tested, eugenol, P/I-menthone, pulegone, α/β-thujone, l-carvone, E/Z-citral, citronellal, methyl benzoate, benzyl acetate, methyl salicylate and 3-octanol showed a significant repellency on vespid workers. These compounds are likely responsible for the repellency of their corresponding essential oils. These repellent essential oils and their active compositions have great potential for efficient, environmentally sound semiochemical-based IPM of pestiferous vespid wasps. © 2012 Society of Chemical Industry.

Theoretical study on the adsorption and relative stability of conformers of L-ascorbic acid on γ - alumina (100) surface

Science.gov (United States)

Mozaffari Majd, M.; Dabbagh, H. A.; Farrokhpour, H.; Najafi Chermahini, A.

2017-11-01

The adsorption energies (Eads) and relative stabilities of selected conformers of the most stable tautomer of L-ascorbic acid (vitamin C) on the dehydroxylated γ-alumina (100) surface were calculated in both gas phase and solvent (water) using the density functional theory (DFT) method. The selected conformers were related to the different rotational angles of OH groups of L-ascorbic acid. The conformational analysis of bare tautomer in both gas and water showed that the conformer No.20 (conf. 20) and 13 (conf. 13) with the dihedral angles of H15sbnd O10sbnd C11sbnd C9 (-73°) and H20sbnd O19sbnd C9sbnd C11 (-135°) were the most stable and unstable conformers, respectively. The performed calculations in the presence of surface showed that the interaction of the conformers with the surface changes their relative stabilities and structures in both gas phase and water. The Ead of each conformer was calculated and it was determined that conf. 8 and conf. 16 have the highest value of Ead in the gas phase (-62.56 kcal/mol) and water (-54.44 kcal/mol), respectively. The optimized structure of each conformer on the surface and the number of hydrogen bonds between it and surface along with their bond lengths were determined.

Operational strategy, economic and environmental performance of sludge treatment reed bed systems - based on 28 years of experience

DEFF Research Database (Denmark)

Nielsen, S.; Larsen, Julie Dam

2016-01-01

Sludge treatment reed bed (STRB) systems have been used for dewatering and mineralisation of sludge in Europe since 1988. STRB systems provide substantial environmental, economic, and operational benefits compared to mechanical sludge dewatering solutions such as belt presses and centrifuges....... They require less energy, no chemicals, reduce the sludge volume and produce bio solids with dry solid contents up to 20-40% under Danish climate conditions, depending on the sludge quality. Experience has shown that sludge treated in STRBs represents a high quality product with a low content of pathogens...... compared to conventional mechanical dewatering devices, delivering an economic break-even of about 3-5 years. This paper provides an overview of the operation and maintenance costs and environmental benefits of a typical STRB based on the experiences gained from the operation of a large number of STRBs...

Sewage sludge conditioning with the application of ash from biomass-fired power plant

Science.gov (United States)

Wójcik, Marta; Stachowicz, Feliks; Masłoń, Adam

2018-02-01

During biomass combustion, there are formed combustion products. Available data indicates that only 29.1 % of biomass ashes were recycled in Poland in 2013. Chemical composition and sorptive properties of ashes enable their application in the sewage sludge treatment. This paper analyses the impact of ashes from biomass-combustion power plant on sewage sludge dewatering and higienisation. The results obtained in laboratory tests proved the possitive impact of biomass ashes on sewage sludge hydration reduction after dewatering and the increase of filtrate volume. After sludge conditioning with the use of biomass combustion by-products, the final moisture content decreased by approximatelly 10÷25 % in comparison with raw sewage sludge depending on the method of dewatering. The application of biomass combustion products in sewage sludge management could provide an alternative method of their utilization according to law and environmental requirements.

Mapeamento dos suportes de auxílio ao ensino tradicional: uma contextualização da biblioteca, do livro, do computador, da internet e da tecnologia na educação

Directory of Open Access Journals (Sweden)

Gildenir Carolino Santos

2003-01-01

Full Text Available O presente artigo tem como objetivo, mostrar de forma lógica através de um breve histórico, a constituição da palavra biblioteca, da transformação dos suportes de registro com a tecnologia, surgimento da Internet. Faz uma explanação sobre os livros e seus formatos desde o seu surgimento, bem como o envolvimento do computador no mundo dos livros. Define através da literatura por alguns autores, o conceito sobre biblioteca digital, eletrônica, virtual ou polimídia. Destaca alguns pontos da leitura digital realizada na Internet, além da utilização da tecnologia na educação. Volta-se a falar sobre a Internet e a sua função multimídia social. Por último, o artigo aborda os desafios do ensino a distância (EAD, a elaboração de material didático e a relação do EAD com a biblioteca digital.The present article has as objective, to show of logical form through a historical briefing, the constitution of the word library, the transformation them supports of register with the technology, it sprouting of the Internet . It makes a communication on books and its formats since its sprouting, as well as the envolvement of the computer in the world of books. Defines through literature for some authors, the concept on digital, electronic, virtual or polimídia library. It detaches some points of the carried through digital reading in the Internet, beyond the uses of the technology in the education. It is turned to say on the Internet and its social multimedia function to it. Finally, the article approaches the challenges of the distance education (EAD, the elaboration of didactic material and the relation of the EAD with the digital library.

Analysis of plasmid-mediated quinolone resistance genes in clinical isolates of the tribe Proteeae from Argentina: First report of qnrD in the Americas.

Science.gov (United States)

Albornoz, Ezequiel; Lucero, Celeste; Romero, Genara; Rapoport, Melina; Guerriero, Leonor; Andres, Patricia; Galas, Marcelo; Corso, Alejandra; Petroni, Alejandro

2014-12-01

To analyse the occurrence and prevalence of plasmid-mediated quinolone resistance (PMQR) genes in the tribe Proteeae, 81 isolates (65 Proteus spp., 12 Morganella morganii and 4 Providencia stuartii) consecutively collected in 66 hospitals belonging to the WHONET-Argentina Resistance Surveillance Network were studied. Of the 81 isolates, 50 (62%) were susceptible to quinolones [43/65 (66%) Proteus spp. and 7/12 (58%) M. morganii). The remaining 31 isolates (22 Proteus spp., 5 M. morganii and all P. stuartii) showed high-level resistance to nalidixic acid (NAL) and decreased susceptibility or resistance to ciprofloxacin. All NAL-resistant isolates harboured mutations associated with quinolone resistance (MAQRs) in both gyrA (S83I/R) and parC (S80I/R), and some also had MAQRs in gyrB (S464Y/F). The unique PMQR gene detected was qnrD, which was found in 2/81 isolates (Proteus mirabilis Q1084 and Proteus vulgaris Q5169), giving a prevalence of 2.5% in Proteeae. These two isolates were from different geographical regions and both harboured MAQRs in gyrA and parC. The qnrD genes were located on the related plasmids pEAD1-1 (2683bp) and pEAD1-2 (2669bp). Plasmid pEAD1-1 was 100% identical to pCGH15 and differed in only three nucleotides from pDIJ09-518a, which were previously found in clinical isolates of P. mirabilis (China) and Providencia rettgeri (France), respectively, whilst pEAD1-2 was not previously described. The extended-spectrum β-lactamase CTX-M-2 was found in 27% (22/81) of the isolates and was significantly associated with quinolone resistance but not with qnrD (only P. mirabilis Q1084 expressed CTX-M-2). This is the first report of qnrD in the Americas. Copyright © 2014 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

Pheromones of milkweed bugs (Heteroptera: Lygaeidae) attract wayward plant bugs: Phytocoris mirid sex pheromone.

Science.gov (United States)

Zhang, Qing-He; Aldrich, Jeffrey R

2003-08-01

The synthetic aggregation pheromone of the large milkweed bug, Oncopeltus fasciatus (Dallas) (Lygaeinae), also attracted males of the plant bug, Phytocoris difficilis Knight (Miridae). Field testing partial blends against the six-component blend comprising the Oncopeltus pheromone showed that cross-attraction of P. difficilis males was due to synergism between (E)-2-octenyl acetate and (E,E)-2,4-hexadienyl acetate. Hexyl acetate was abundant in the metathoracic scent gland (MSG) secretion of P. difficilis males, but because female P. difficilis could not initially be found in the field, further combinatorial tests were guided by prior research on the pheromones of two Phytocoris species in the western United States. The combination of hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates was as attractive to P. difficilis males as the milkweed bug pheromone, yet no milkweed bugs were drawn to this blend. Gas chromatographic (GC)-electroantennographic detection (EAD) and GC-mass spectrometric (MS) analyses of female P. difficilis MSGs determined that their secretion contained predominantly hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates (all strongly EAD-active)-the latter two compounds found only in trace amounts from males-plus five minor female-specific compounds, three of which were EAD-active. (E,E)-2,4-Hexadienyl acetate was not detected from P. difficilis females or males. The blend of the three major components, hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates (2:1.5:1 by volume), was as attractive as the blend of all six EAD-active compounds identified from females, indicating that this ternary blend constitutes the sex pheromone of P. difficilis. Hexyl acetate with (E)-2-octenyl acetate also attracted males of another species, P. breviusculus Reuter, but addition of (E)-2-hexenyl acetate and/or (E,E)-2,4-hexadienyl acetate inhibited attraction of P. breviusculus males. Attraction of P. difficilis males occurred mainly during the first half of scotophase. The

A produção audiovisual na virtualização do ensino superior: subsídios para a formação docente/Audiovisual production in the virtualization of higher education: a contribution for teacher education

Directory of Open Access Journals (Sweden)

Dulce Márcia da Cruz

2007-01-01

Full Text Available O Brasil vive nos últimos dez anos uma crescente expansão da educação a distância (EAD e da virtualização da sala de aula no ensino superior. Se antes de 1995 a produção da EAD era uma tarefa dos profissionais de rádio e TV, com as mídias digitais esse processo também passa pelas mãos de docentes que podem produzir, transmitir e gerenciar cursos e disciplinas na internet, tornando-se autores da produção audiovisual e hipertextual de suas aulas. Visando contribuir para que os docentes tenham noções básicas sobre como produzir para a EAD e para disciplinas semi-presenciais usando meios audiovisuais e hipertextuais, este artigo descreve os elementos básicos que compõem a linguagem cinematográfica e as narrativas digitais que incorporam a interatividade. Finalmente, apresenta alguns fundamentos da produção para as mídias mais comuns na EAD brasileira: material impresso, teleconferência, videoconferência, multimídia/hipermídia e ambientes virtuais de aprendizagem. The past ten years had seen a significant expansion of the distance and hybrid education in Higher Education – HE in Brazil. Before 1995 the production of distance education (DE was a task of radio and TV professionals, with the adoption of digital media this process started to be a task of the teachers too, who can now produce, transmit and manage courses and disciplines in the Internet, becoming authors of the audiovisual and hypertextual production of its lessons. The objective of this article is to offer basic notions to the teachers about how to create DE and hybrid education incorporating audiovisual and hypertextual media, describing the main elements that compose the cinematographic language and the digital narratives that incorporate the interactivity. Finally, it presents some principles of the production for the most common media used for DE in Brazil: printed material, teleconference, videoconference, hypermedia/multimedia and Virtual Learning

A study on the treatment of radioactive slurry liquid waste

International Nuclear Information System (INIS)

Jeong, Gyeong Hwan; Chung, U. S.; Baik, S. T.; Park, S. K.; Moon, J.S.; Jung, K.J.

1998-12-01

The influence of anionic flocculants on the dewatering of radioactive slurries has been investigated in a laboratory-scale vacuum filtration unit. Simultaneously the influence of certain surfactants on the dewatering of radioactive slurries with anionic flocculants has also been investigated. Test results show that the flocculated filter cake generally contains higher residual water than the unflocculated cake. The non-ionic surfactant Triton X-100 was effective in reducing the moisture content of the cake

Development of harvesting and up concentration technologies for microalgae as an ingredient in fish feed

DEFF Research Database (Denmark)

Safafar, Hamed; Jacobsen, Charlotte; Møller, Per

2014-01-01

andfish oil. In applications of algae in fish feed, it is essential to produce a product comparable to fish proteinand fish oil both in terms of quality and costs.Downstream processing of microalgae includes harvest, dewatering, cell rupture, fractionation and drying.The dewatering and drying which...... ingredients forfish feed. Further we evaluate the chemical composition of six different microalgae species including;Nanochloropsis limnethica, Chlorella sorokiniana, Phaeodactylum tinctorium, Dunaliella salina,Nannochloropsis salina and Nannochloropsis occulata ....

A study on the treatment of radioactive slurry liquid waste

Energy Technology Data Exchange (ETDEWEB)

Jeong, Gyeong Hwan; Chung, U. S.; Baik, S. T.; Park, S. K.; Moon, J.S.; Jung, K.J

1998-12-01

The influence of anionic flocculants on the dewatering of radioactive slurries has been investigated in a laboratory-scale vacuum filtration unit. Simultaneously the influence of certain surfactants on the dewatering of radioactive slurries with anionic flocculants has also been investigated. Test results show that the flocculated filter cake generally contains higher residual water than the unflocculated cake. The non-ionic surfactant Triton X-100 was effective in reducing the moisture content of the cake.

Recycling of nutrients through struvite precipitation from digestions residues; Aatervinning av naering genom struvitfaellninggsaemnen fraan roetrest

Energy Technology Data Exchange (ETDEWEB)

Fransson, Liisa; Loewgren, Sofia; Thelin, Gunnar (Ekobalans Fenix AB, Lund (Sweden))

2010-05-15

The aim of the project which is described in this report was to gather information about struvite precipitation and studies that have been performed within this area, and also to investigate struvite precipitation in four different digestates through laboratory experiments. Digestates from biogas plants with household waste, beet, manure and distillery residues as raw materials were used in this study. Struvite, MgNH{sub 4}PO{sub 4}-6H{sub 2}O, is a white crystal powder which is soluble at low pH and precipitates at pH 7-11. For struvite to precipitate the solution also has to be over saturated and the influence of other competitive ions has to be low. Many studies in struvite precipitation have been done as laboratory trials and in pilot plants. The experiments were performed on for example digestates from sewage treatment plants. The reactors were stirred or aerated and the solutions were either dewatered or non dewatered. The experiments were performed both with and without the addition of phosphate. A few full scale plants are also described in this report. Most of them consist of a fluidized bed and are connected to sewage treatment plants. Dewatered sewage sludge is most commonly used but there are also examples of non dewatered sludge. Some of the products from the full scale plants are sold as fertilizers. MgCl{sub 2}-6H{sub 2}O is the most common magnesium additive in the studies that have been summarized in this report, but for example Mg(OH){sub 2} has also been used in a few cases. The laboratory experiments in this report were performed on non dewatered and dewatered digestates. The dewatering was performed by filtration in three steps, except for the digestate from distillery residues which was centrifuged. The experiments were performed with and without phosphate addition. First, a few trials on synthetic solutions were performed to verify the chosen experimental conditions. All of the trials, with the synthetic and digestate solutions, were

Evaluation of Management of Water Release for Painted Rocks Reservoir, Bitterroot River, Montana, 1984 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Lere, Mark E. (Montana Department of Fish, Wildlife and Parks, Missoula, MT)

1984-11-01

Baseline fisheries and habitat data were gathered during 1983 and 1984 to evaluate the effectiveness of supplemental water releases from Painted Rocks Reservoir in improving the fisheries resource in the Bitterroot River. Discharge relationships among main stem gaging stations varied annually and seasonally. Flow relationships in the river were dependent upon rainfall events and the timing and duration of the irrigation season. Daily discharge monitored during the summers of 1983 and 1984 was greater than median values derived at the U.S.G.S. station near Darby. Supplemental water released from Painted Rocks Reservoir totaled 14,476 acre feet in 1983 and 13,958 acre feet in 1984. Approximately 63% of a 5.66 m{sup 3}/sec test release of supplemental water conducted during April, 1984 was lost to irrigation withdrawals and natural phenomena before passing Bell Crossing. A similar loss occurred during a 5.66 m{sup 3}/sec test release conducted in August, 1984. Daily maximum temperature monitored during 1984 in the Bitterroot River averaged 11.0, 12.5, 13.9 and 13.6 C at the Darby, Hamilton, Bell and McClay stations, respectively. Chemical parameters measured in the Bitterroot River were favorable to aquatic life. Population estimates conducted in the Fall, 1983 indicated densities of I+ and older rainbow trout (Salmo gairdneri) were significantly greater in a control section than in a dewatered section (p < 0.20). Numbers of I+ and older brown trout (Salmo trutta) were not significantly different between the control and dewatered sections (p > 0.20). Population and biomass estimates for trout in the control section were 631/km and 154.4 kg/km. In the dewatered section, population and biomass estimates for trout were 253/km and 122.8 kg/km. The growth increments of back-calculated length for rainbow trout averaged 75.6 mm in the control section and 66.9mm in the dewatered section. The growth increments of back-calculated length for brown trout averaged 79.5 mm in the

An Investigation on In-Vessel Composting of Pistachio Residuals with Different Additions

OpenAIRE

M Jalili; M Mokhtari; AA Ebrahimi; F Boghri

2016-01-01

Background and Objective: About 1.35×105 tons of pistachio waste are produced in annually Iran that can result in environmental problems if managed improperly. . The purpose of this study was to investigate in-vessel composting of pistachio residuals with addition of cow manure and dewatered sludge as a recycling alternative. Materials and Methods: Pistachios wastes were combined with weight ratio of 5.5:10 (dewatered sludge: pistachio waste) and weight ratio of 1:10 (Cow manure: pi...

Performance Validation and Scaling of a Capillary Membrane Solid-Liquid Separation System

Energy Technology Data Exchange (ETDEWEB)

Rogers, S; Cook, J; Juratovac, J; Goodwillie, J; Burke, T

2011-10-25

Algaeventure Systems (AVS) has previously demonstrated an innovative technology for dewatering algae slurries that dramatically reduces energy consumption by utilizing surface physics and capillary action. Funded by a $6M ARPA-E award, transforming the original Harvesting, Dewatering and Drying (HDD) prototype machine into a commercially viable technology has required significant attention to material performance, integration of sensors and control systems, and especially addressing scaling issues that would allow processing extreme volumes of algal cultivation media/slurry. Decoupling the harvesting, dewatering and drying processes, and addressing the rate limiting steps for each of the individual steps has allowed for the development individual technologies that may be tailored to the specific needs of various cultivation systems. The primary performance metric used by AVS to assess the economic viability of its Solid-Liquid Separation (SLS) dewatering technology is algae mass production rate as a function of power consumption (cost), cake solids/moisture content, and solids capture efficiency. An associated secondary performance metric is algae mass loading rate which is dependent on hydraulic loading rate, area-specific hydraulic processing capacity (gpm/in2), filter:capillary belt contact area, and influent algae concentration. The system is capable of dewatering 4 g/L (0.4%) algae streams to solids concentrations up to 30% with capture efficiencies of 80+%, however mass production is highly dependent on average cell size (which determines filter mesh size and percent open area). This paper will present data detailing the scaling efforts to date. Characterization and performance data for novel membranes, as well as optimization of off-the-shelf filter materials will be examined. Third party validation from Ohio University on performance and operating cost, as well as design modification suggestions will be discussed. Extrapolation of current productivities

A scent shield to survive: identification of the repellent compounds secreted by the male offspring of the cuckoo bumblebee Bombus vestalis

Czech Academy of Sciences Publication Activity Database

Lhomme, P.; Ayasse, M.; Valterová, Irena; Lecocq, T.; Rasmont, P.

2015-01-01

Roč. 157, č. 3 (2015), s. 263-270 ISSN 0013-8703 Institutional support: RVO:61388963 Keywords : Hymenoptera * Apidae * Psithyrus * social parasitism * repellent * GC-EAD * chemical camouflage Subject RIV: EG - Zoology Impact factor: 1.442, year: 2015

Are the Wild and Laboratory Insect Populations Different in Semiochemical Emission? The Case of the Medfly Sex Pheromone

Czech Academy of Sciences Publication Activity Database

Vaníčková, Lucie; do Nascimento, R. R.; Hoskovec, Michal; Ježková, Z.; Břízová, Radka; Tomčala, Aleš; Kalinová, Blanka

2012-01-01

Roč. 60, č. 29 (2012), s. 7168-7176 ISSN 0021-8561 Institutional support: RVO:61388963 Keywords : GC X GC/TOFMS * GC-EAD * principal component analysis Subject RIV: CC - Organic Chemistry Impact factor: 2.906, year: 2012

Solar drying in sludge management in Turkey

Energy Technology Data Exchange (ETDEWEB)

Kamil Salihoglu, Nezih; Pinarli, Vedat; Salihoglu, Guray [Faculty of Engineering and Architecture, Environmental Engineering Department, Uludag University, 16059, Bursa (Turkey)

2007-08-15

Two main wastewater treatment plants in Bursa city in Turkey will start to operate and produce at least 27,000 tons of dry solids per year by the end of 2006. The purpose of this study was to investigate an economical solution to the sludge management problem that Bursa city would encounter. The general trend in Turkey is mechanical dewatering to obtain a dry solid (DS) content of 20%, and liming the mechanically dewatered sludge to reach the legal land filling requirement, 35% DS content. This study recommends limited liming and solar drying as an alternative to only-liming the mechanically dewatered sludge. Open and covered solar sludge drying plants were constructed in pilot scale for experimental purposes. Dry solids and climatic conditions were constantly measured. Faecal coliform reduction was also monitored. The specially designed covered solar drying plant proved to be more efficient than the open plant in terms of drying and faecal coliform reduction. It was found that, if the limited liming and solar drying method was applied after mechanical dewatering instead of only-liming method, the total amount of the sludge to be disposed would be reduced by approximately 40%. This would lead to a reduction in the transportation, handling, and land filling costs. The covered drying system would amortize itself in 4 years. (author)

PORTFOLIO OF POTENTIAL STRATEGIES IN AERONAUTIC MAINTENANCE

International Nuclear Information System (INIS)

Rolet, S.

2010-01-01

EADS divisions aim more and more at developing services associated to their platforms. EADS divisions, like Airbus and Eurocopter, are investigating on services associated to their platforms in order to add them value. One possible service consists in structural maintenance operation assistance, especially for NDT operations performed by the customer. EADS Innovation Works envisages three different and complementary enhanced structural maintenance categories. Enhanced NDT improves standard NDT operation environment. This is made possible by the existence of 'smart' NDT tools that are computer based and therefore able to support other functions. These functions range from local smart data processing and display to remote expert assisted operation. Passive Sensor Network relies on sensors permanently installed on aircraft structure. Interrogation of sensors is performed on ground and off line (while structure is not loaded except by its own weight). It can be done at arbitrary times in order to determine structure health. The aim is to give easy access to some hidden ''hot spots,'' to reduce human factor in structure health assessment and optimize maintenance. Structural Health Monitoring goes a step beyond Passive Sensor Network, because interrogation units are on board the aircraft and may be connected to aircraft network. It allows to use on-line techniques such as adapted acoustic emission and to automatically raise an alarm when a defect appears in the structure. This paper presents these different ways of improving structural maintenance operations in service, with their respective advantages and limitations.

Triggered Firing and Atrial Fibrillation in Transgenic Mice With Selective Atrial Fibrosis Induced by Overexpression of TGF-β1

Science.gov (United States)

Choi, Eue-Keun; Chang, Po-Cheng; Lee, Young-Soo; Lin, Shien-Fong; Zhu, Wuqiang; Maruyama, Mitsunori; Fishbein, Michael C.; Chen, Zhenhui; der Lohe, Michael Rubart-von; Field, Loren J.; Chen, Peng-Sheng

2013-01-01

Background Calcium transient triggered firing (CTTF) is induced by large intracellular calcium (Cai) transient and short action potential duration (APD). We hypothesized that CTTF underlies the mechanisms of early afterdepolarization (EAD) and spontaneous recurrent atrial fibrillation (AF) in transgenic (Tx) mice with overexpression of transforming growth factor β1 (TGF-β1). Methods and Results MHC-TGFcys33ser Tx mice develop atrial fibrosis because of elevated levels of TGF-β1. We studied membrane potential and Cai transients of isolated superfused atria from Tx and wild-type (Wt) littermates. Short APD and persistently elevated Cai transients promoted spontaneous repetitive EADs, triggered activity and spontaneous AF after cessation of burst pacing in Tx but not Wt atria (39% vs. 0%, P=0.008). We were able to map optically 4 episodes of spontaneous AF re-initiation. All first and second beats of spontaneous AF originated from the right atrium (4/4, 100%), which is more severely fibrotic than the left atrium. Ryanodine and thapsigargin inhibited spontaneous re-initiation of AF in all 7 Tx atria tested. Western blotting showed no significant changes of calsequestrin or sarco/endoplasmic reticulum Ca2+-ATPase 2a. Conclusions Spontaneous AF may occur in the Tx atrium because of CTTF, characterized by APD shortening, prolonged Cai transient, EAD and triggered activity. Inhibition of Ca2+ release from the sarcoplasmic reticulum suppressed spontaneous AF. Our results indicate that CTTF is an important arrhythmogenic mechanism in TGF-β1 Tx atria. PMID:22447020

Application of C_6_0, C_7_2 and carbon nanotubes as anode for lithium-ion batteries: A DFT study

International Nuclear Information System (INIS)

Najafi, Meysam

2017-01-01

The application of C_6_0, C_7_2, CNT (8, 0) and CNT (10, 0) as anode materials for Lithium-ion batteries were investigated by density functional theory (DFT) calculations. Results show that the average values of voltage cell (V_c_e_l_l) and adsorption energy (E_a_d) of CNT (8, 0) and CNT (10, 0) were higher than C_6_0 and C_7_2 ca 0.327 V and 6.52 kcal/mol, respectively. The NH_2 functionalization of studied nanostructures as a strategy to improve the performance of these systems as anode materials of Lithium-ion batteries were investigated. Results show that, NH_2 functionalization of studied nanostructures increase the average values of voltage cell and adsorption energy ca 0.197 V and 8.20 kcal/mol, respectively. Obtained results propose that NH_2 functionalized C_7_2 and CNT (10, 0) have larger V_c_e_l_l and E_a_d values and therefore these nanostructures have higher potential as anode material for Lithium-ion battery. - Highlights: • C_6_0 and CNT (10, 0) as anode materials for Lithium-ion batteries were investigated. • V_c_e_l_l and E_a_d of CNT (8, 0) and CNT (10, 0) were higher than C_6_0 and C_7_2 ca. • NH_2 functionalization of C_6_0 improve the performance of it as anode materials of Lithium-ion batteries.

In situ electron microscopy studies of electromechanical behavior in metals at the nanoscale using a novel microdevice-based system

Energy Technology Data Exchange (ETDEWEB)

Kang, Wonmo, E-mail: wonmo.kang.ctr.ks@nrl.navy.mil; Beniam, Iyoel; Qidwai, Siddiq M. [Naval Research Laboratory, Washington, DC 20375 (United States)

2016-09-15

Electrically assisted deformation (EAD) is an emerging technique to enhance formability of metals by applying an electric current through them. Despite its increasing importance in manufacturing applications, there is still an unresolved debate on the nature of the fundamental deformation mechanisms underlying EAD, mainly between electroplasticity (non-thermal effects) and resistive heating (thermal effects). This status is due to two critical challenges: (1) a lack of experimental techniques to directly observe fundamental mechanisms of material deformation during EAD, and (2) intrinsic coupling between electric current and Joule heating giving rise to unwanted thermally activated mechanisms. To overcome these challenges, we have developed a microdevice-based electromechanical testing system (MEMTS) to characterize nanoscale metal specimens in transmission electron microscopy (TEM). Our studies reveal that MEMTS eliminates the effect of Joule heating on material deformation, a critical advantage over macroscopic experiments, owing to its unique scale. For example, a negligible change in temperature (<0.02 °C) is predicted at ∼3500 A/mm{sup 2}. Utilizing the attractive features of MEMTS, we have directly investigated potential electron-dislocation interactions in single crystal copper (SCC) specimens that are simultaneously subjected to uniaxial loading and electric current density up to 5000 A/mm{sup 2}. Our in situ TEM studies indicate that for SCC, electroplasticity does not play a key role as no differences in dislocation activities, such as depinning and movement, are observed.

Monitoring of occupational exposure in manufacturing of stainless steel constructions. Part I: Chromium, iron, manganese, molybdenum, nickel and vanadium in the workplace air of stainless steel welders

International Nuclear Information System (INIS)

Kucera, J.; Hnatowicz, V.; Bencko, V.; Papayova, A.; Saligova, D.; Tejral, J.; Borska, L.

2000-01-01

Exposure to workplace airborne pollutants was examined in a group of 20 workers dealing mainly with welding, polishing, drilling and assembling of stainless steel constructions. Monitoring of airborne particulate matter (ARM) was performed using both personal and stationary samplers. For the personal full-shift monitoring, a SKC 224 PCRX-4 constant flow rate pump was used which was connected to a sampling head with mixed cellulose matched-weight filters having a diameter of 32 mm and a 0.8 μm pore size. The constant flow rate amounted to 2 L min -1 . For the stationary sampling, the ''Gent'' stacked filter unit PM10 sampler was used, operating at a flow rate of 16 L min -1 . It collects particles having an equivalent aerodynamic diameter (EAD) of less than 10,um in the separate ''coarse'' (2-10 μm EAD) and ''fine'' (< 2 μm EAD) size fractions on two sequential polycarbonate (Costar, Nuclepore) filters with a 47 mm diameter. The filters of both types were analyzed by instrumental neutron activation analysis (INAA). Of the elements determined, results for chromium, iron, manganese, molybdenum, nickel and vanadium are presented. Procedures for quality assurance of both sampling and analytical stages are described. Sampling of biological material for elemental analysis (hair, nails, urine and blood and/or serum) of exposed and control persons in contamination-free conditions was also performed. In addition, saliva samples were collected for studying immunological and genotoxicity aspects of occupational exposure. (author)

A Density Functional Tight Binding Study of Acetic Acid Adsorption on Crystalline and Amorphous Surfaces of Titania

Directory of Open Access Journals (Sweden)

Sergei Manzhos

2015-02-01

Full Text Available We present a comparative density functional tight binding study of an organic molecule attachment to TiO2 via a carboxylic group, with the example of acetic acid. For the first time, binding to low-energy surfaces of crystalline anatase (101, rutile (110 and (B-TiO2 (001, as well as to the surface of amorphous (a- TiO2 is compared with the same computational setup. On all surfaces, bidentate configurations are identified as providing the strongest adsorption energy, Eads = −1.93, −2.49 and −1.09 eV for anatase, rutile and (B-TiO2, respectively. For monodentate configurations, the strongest Eads = −1.06, −1.11 and −0.86 eV for anatase, rutile and (B-TiO2, respectively. Multiple monodentate and bidentate configurations are identified on a-TiO2 with a distribution of adsorption energies and with the lowest energy configuration having stronger bonding than that of the crystalline counterparts, with Eads up to −4.92 eV for bidentate and −1.83 eV for monodentate adsorption. Amorphous TiO2 can therefore be used to achieve strong anchoring of organic molecules, such as dyes, that bind via a -COOH group. While the presence of the surface leads to a contraction of the band gap vs. the bulk, molecular adsorption caused no appreciable effect on the band structure around the gap in any of the systems.

Identification and field and laboratory tests of the sex pheromone of Cerconota anonella Sepp. (Lepidoptera: Oecophoridae)

Czech Academy of Sciences Publication Activity Database

Pires, E. V.; Mendonca, A. L.; Vaníčková, Lucie; Serra, M. S. J.; da Silva, R. C. C.; dos Santos, D. C.; Campos, R. S.; Santana, A. E. G.; do Nascimento, R. R.

2016-01-01

Roč. 140, 1/2 (2016), s. 72-80 ISSN 0931-2048 Institutional support: RVO:61388963 Keywords : Annona fruit borer * GC x GC-TOFMS * GC-EAD * sex pheromone Subject RIV: EG - Zoology Impact factor: 1.641, year: 2016

Design and development of the 2m resolution camera for ROCSAT-2

Science.gov (United States)

Uguen, Gilbert; Luquet, Philippe; Chassat, François

2017-11-01

EADS-Astrium has recently completed the development of a 2m-resolution camera, so-called RSI (Remote Sensing Instrument), for the small-satellite ROCSAT-2, which is the second component of the long-term space program of the Republic of China. The National Space Program Office of Taïwan selected EADS-Astrium as the Prime Contractor for the development of the spacecraft, including the bus and the main instrument RSI. The main challenges for the RSI development were: - to introduce innovative technologies in order to meet the high performance requirements while achieving the design simplicity necessary for the mission (low mass, low power) - to have a development approach and verification compatible with the very tight development schedule This paper describes the instrument design together with the development and verification logic that were implemented to successfully meet these objectives.

Effect of the Matching Circuit on the Electromechanical Characteristics of Sandwiched Piezoelectric Transducers

Directory of Open Access Journals (Sweden)

Shuyu Lin

2017-02-01

Full Text Available The input electrical impedance behaves as a capacitive when a piezoelectric transducer is excited near its resonance frequency. In order to increase the energy transmission efficiency, a series or parallel inductor should be used to compensate the capacitive impedance of the piezoelectric transducer. In this paper, the effect of the series matching inductor on the electromechanical characteristics of the piezoelectric transducer is analyzed. The dependency of the resonance/anti-resonance frequency, the effective electromechanical coupling coefficient, the electrical quality factor and the electro-acoustical efficiency on the matching inductor is obtained. It is shown that apart from compensating the capacitive impedance of the piezoelectric transducer, the series matching inductor can also change the electromechanical characteristics of the piezoelectric transducer. When series matching inductor is increased, the resonance frequency is decreased and the anti-resonance unchanged; the effective electromechanical coupling coefficient is increased. For the electrical quality factor and the electroacoustic efficiency, the dependency on the matching inductor is different when the transducer is operated at the resonance and the anti-resonance frequency. The electromechanical characteristics of the piezoelectric transducer with series matching inductor are measured. It is shown that the theoretically predicted relationship between the electromechanical characteristics and the series matching inductor is in good agreement with the experimental results.

Effect of the Matching Circuit on the Electromechanical Characteristics of Sandwiched Piezoelectric Transducers.

Science.gov (United States)

Lin, Shuyu; Xu, Jie

2017-02-10

The input electrical impedance behaves as a capacitive when a piezoelectric transducer is excited near its resonance frequency. In order to increase the energy transmission efficiency, a series or parallel inductor should be used to compensate the capacitive impedance of the piezoelectric transducer. In this paper, the effect of the series matching inductor on the electromechanical characteristics of the piezoelectric transducer is analyzed. The dependency of the resonance/anti-resonance frequency, the effective electromechanical coupling coefficient, the electrical quality factor and the electro-acoustical efficiency on the matching inductor is obtained. It is shown that apart from compensating the capacitive impedance of the piezoelectric transducer, the series matching inductor can also change the electromechanical characteristics of the piezoelectric transducer. When series matching inductor is increased, the resonance frequency is decreased and the anti-resonance unchanged; the effective electromechanical coupling coefficient is increased. For the electrical quality factor and the electroacoustic efficiency, the dependency on the matching inductor is different when the transducer is operated at the resonance and the anti-resonance frequency. The electromechanical characteristics of the piezoelectric transducer with series matching inductor are measured. It is shown that the theoretically predicted relationship between the electromechanical characteristics and the series matching inductor is in good agreement with the experimental results.

Euroopa lennundus- ja kaitsetööstuskontserni eesmärgiks 15 000 kosmoseturisti aastas

Index Scriptorium Estoniae

2007-01-01

Euroopa Lennundus- ja Kaitsetööstuskontsern (EADS) ning Briti miljardäri Richard Bransoni firmaVirgin Galactic lubavad lähitulevikus hakata korraldama kosmosereise turistidele, juba praegu pakuvad venelased rahakatele soovijatele sõitu Sojuz-laevadel rahvusvahelisse kosmosejaama ISS

Former Virginia Tech Aerospace and Ocean Engineering Department Head Dies

OpenAIRE

Gilbert, Karen

2003-01-01

James B. Eades, Jr., retired aerospace research scientist from Bluefield, W. Wa., and former professor and department head of aerospace and ocean engineering at Virginia Tech, died Dec. 14 at Veteran's Hospital in Washington, D.C. He was 80.

The Fundamentals of Waste Water Sludge Characterization and Filtration

Energy Technology Data Exchange (ETDEWEB)

Scales, Peter J.; Dixon, David R.; Harbour, Peter J.; Stickland, Anthony D.

2003-07-01

The move to greater emphasis on the disposal of waste water sludges through routes such as incineration and the added cost of landfill emplacement puts high demands on dewatering technology for these sludges. A dear problem in this area is that waste water sludges are slow and difficult to dewater and traditional methods of laboratory measurement for prediction of filtration performance are inadequate. This is highly problematic for the design and operational optimisation of centrifuges, filters and settling devices in the waste water industry. The behaviour is assessed as being due to non-linear behaviour of these sludges which negates the use of classical approaches. These approaches utilise the linear portion of a t versus V{sup 2} plot (where t is the time to filtration and V is the specific filtrate volume) to extract a simple Darcian permeability. Without this parameter, a predictive capacity for dewatering using current theory is negated. (author)

A review of methods developed to solve the issue of weak mature fine tailings

Energy Technology Data Exchange (ETDEWEB)

Long, M.; Ulrich, A.; Sego, D. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering

2010-07-01

This PowerPoint presentation discussed new techniques for managing weak mature fine tailings (MFT) produced during the oil sands refining process. The techniques included non-segregating tailings, freeze-thaw dewatering, atmospheric drying, and dewatering by vegetation. MFT are produced after water from oil sands slurries is decanted. MFT contain a complex chemical interaction of clays and hydrocarbons. A large proportion of the solids in MFTs are clay minerals and clay-sized. MFTs have low rates of sedimentation and consolidation, and a low bearing capacity and shear strength with high compressibility. MFTs cannot physically support remediation activities, and must be stored in an impounded area. More aggressive dewatering and stabilization processes are required for MFTs. Atmospheric drying involves the deposition of tailings in order to evaporate water. Thin- and thick-lift deposition schemes are used. Atmospheric drying is often complicated by the formation of a bitumen skin over the tailings. Various case studies were presented. Space requirements and issues related to clay content were reviewed. tabs., figs.

The ASACUSA experiment at CERN's AD antiproton decelerator catches antiprotons in helium, where the antiprotons replace electrons, giving exotics atoms.

CERN Multimedia

Loïez, P

2000-01-01

Photo 03: Laser beams are prepared for shooting at antiprotonic helium atoms. Left to right: Masaki Hori (Tokyo University) and John Eades (CERN). Photo 01: Dye laser triggered by "YAG" laser. Photo 02: Masaki Hori adjusting optical system of laser beams.

Identification of two components of the female sex pheromone of the sugarcane-borer Diatraea flavipennella (Lepidoptera: Crambidae)

Czech Academy of Sciences Publication Activity Database

Kalinová, Blanka; do Nascimento, R. R.; Hoskovec, Michal; Mendonca, A. L.; Silva, E. L.; De Freitas, M. R. T.; Cabral Jr, C. R.; Silva, C. E.; Santana, A. E. G.; Svatoš, Aleš

2012-01-01

Roč. 136, č. 3 (2012), s. 203-211 ISSN 0931-2048 Institutional research plan: CEZ:AV0Z40550506 Keywords : Diatraea flavipennella * sex pheromone * GCxGC-TOFMS * GC-EAD Subject RIV: CC - Organic Chemistry Impact factor: 1.560, year: 2012

Identification of male-borne attractants in Anastrepha fraterculus (Diptera: Tephritidae)

Czech Academy of Sciences Publication Activity Database

Milet-Pinheiro, P.; Navarro, D. M. A.; De Aquino, N. C.; Ferreira, L. L.; Tavares, R. F.; Correia da Silva, R. C.; Lima-Mendonca, A.; Vaníčková, Lucie; Mendonca, A. L.; do Nascimento, R. R.

2015-01-01

Roč. 25, č. 3 (2015), s. 115-122 ISSN 0937-7409 Institutional support: RVO:61388963 Keywords : South American fruit fly * sexual pheromone * male-borne attractants * GC-EAD * behavioral activity Subject RIV: CC - Organic Chemistry Impact factor: 1.863, year: 2015

Solid state silicon based condenser microphone for hearing aid, has transducer chip and IC chip between intermediate chip and openings on both sides of intermediate chip, to allow sound towards diaphragm

DEFF Research Database (Denmark)

2000-01-01

towards diaphragm. Surface of the chip (2) has electrical conductors (14) to connect chip with IC chip (3). USE - For use in miniature electroacoustic devices such as hearing aid. ADVANTAGE - Since sound inlet is covered by filter, dust, moisture and other impurities do not obstruct interior and sound...... inlet of microphone. External electrical connection can be made economically reliable and the thermal stress is avoided with the small size solid state silicon based condenser microphone....

Dislocation and relocation: clarsach and live electronics

OpenAIRE

MacDonald, Alistair

2014-01-01

In writing The Salutation (clarsach and electroacoustic sound) for harpist Catriona McKay in 2002, I wanted to create something which celebrated the history and music of the instrument itself, using studio technology to create a bridge between idiomatic writing for the instrument and environmental/anecdotal sound, including the voice, which referenced place and time. This paper will chart and reflect on the collaborative work we have done together since then, describing our methodology fo...

Tullis Rennie's Muscle Memory: Listening to the Act of Listening

OpenAIRE

Waters, Simon

2015-01-01

This paper explores a recent, broadly 'electroacoustic', fixed medium composition by Tullis Rennie, which uses his background in ethnographic fieldwork to explore (in this case through auto-ethnography) modes of listening, and the role of technologies in mediating this listening. Muscle Memory: A conversation about jazz, with Graham South (trumpet) (2014) begins to answer questions about how one work can comment on and analyse or critique another through its own agency as music, bringing comp...

Interactive Sonification of Weather Data for The Locust Wrath, a Multimedia Dance Performance

OpenAIRE

Lindborg, PerMagnus

2016-01-01

To work flexibly with the sound design for The Locust Wrath, a multimedia dance performance on the topic of climate change, we developed a software for interactive sonification of climate data. An open-ended approach to parameter mapping allowed tweaking and improvisation during rehearsals, resulting in a large range of musical expression. The sonifications represented weather systems pushing through South-East Asia in complex patterns. The climate was rendered as a piece of electroacoustic m...

Geohydrological and environmental isotope observation of Sishen ground waters

International Nuclear Information System (INIS)

Verhagen, B.Th.; Dziembowski, Z.M.

1985-01-01

The dewatering of Sishen Mine in the northern Cape Province supplies good quality water for the mine and surrounding areas. Using various approaches, attempts are made to quantify the remaining storage of ground water. Geohydrological observations provide an estimate based on extrapolating the thickness of dewatered rock. Environmental isotope observations on various borehole outputs show contrasts between different ground-water bodies and their mixtures and allows for some extrapolations of observed trends. Indications are that previous estimates of storage, based on ground-water level changes, are conservative

Characterization of kaolin dispersion using acoustic and electroacoustic spectroscopy

OpenAIRE

Dohnalová Ž.; Svoboda L.; Šulcová P.

2008-01-01

The objective of this work is the investigation of the kaolin dispersion by the ultrasonic techniques. In contact with aqueous solution clay minerals show cation - exchange properties and certain degree of dissolution or rather selective leaching of components. The work is divided into two main parts - determination of zeta potential and particle size distribution. The first part is focused on measuring of zeta potential. Effects of concentration of solid, different kind of electrolytes (0.01...

Characterization of kaolin dispersion using acoustic and electroacoustic spectroscopy

Directory of Open Access Journals (Sweden)

Dohnalová Ž.

2008-01-01

Full Text Available The objective of this work is the investigation of the kaolin dispersion by the ultrasonic techniques. In contact with aqueous solution clay minerals show cation - exchange properties and certain degree of dissolution or rather selective leaching of components. The work is divided into two main parts - determination of zeta potential and particle size distribution. The first part is focused on measuring of zeta potential. Effects of concentration of solid, different kind of electrolytes (0.01 M KCl, 0.01 M MgCl2 and 0.01 M CaCl2, pH and temperature of the dispersions are investigated. The isoelectric points (IEP of kaolin suspension are about pH 4-5. Electrolytes containing monovalent cations such as K+ become zeta potential more negative compared to the values obtained with water. Such behavior is explained by the exchange of K+ ions with H+ ions in the system. When the electrolyte is formed by divalent cations such as Mg2+ or Ca2+, the values of zeta potential become less negative than zeta potential of kaolin in water. The second part is focused on the determination of particle size distribution with respect to dispersing conditions, such as the optimal dispersing agent (Na2SiO3, (NaPO36, Na4P2O7 or Busperse, time and power of ultrasonication and also the tracking of dispersion stability that is expressed by the measuring of particle size distribution during certain time period.

Regional Cerebral Blood Flow differences in early and severe Alzheimer Disease as assessed by SPECT and Principal Component Analysis

International Nuclear Information System (INIS)

Pagani, M.M.E.; Sanchez-Creaspo, A.; Jonsson, C.; Engelin, L.; Danielsson, A.M.; Larsson, S.A.; Jacobsson, H.; Waegner, A.; Salmaso, D.

2002-01-01

Aim: In its development into severe Alzheimer's Disease (AD), early Alzheimer Disease (eAD) involves progressively larger regions of the brain. These regions share close anatomo-functional relationships. The aim of this study was to investigate the rCBF changes occurring in eAD and AD as compared to a group of normal individuals by means of SPECT and Principal Component Analysis. Materials and Methods. Thirty eAD, 17 AD and 66 normal controls (CTR) were included in the study. 99m Tc-HMPAO SPECT, using a three-headed gamma camera, was performed at rest and the uptake in 27 functional bilateral sub-volumes of the brain was assessed by a standardised digitalised brain atlas. Data were grouped into anatomo-functionally connected regions by means of PCA analysis performed on all 113 individuals. Analysis of variance (ANOVA) was used to test the significance of the differences in flow in such functional regions and data were co-variated for age differences. Results. In the global analysis, rCBF significantly differed between groups (0.001) with a progressive reduction of flow from CTR to AD. PCA reduced the 54 variables to 11 anatomo-functional regions that interacted with groups (p<0.001) and gender (p<0.001). In the overall analysis the three groups differed significantly in all functional regions except for bilateral occipital cortex, anterior cingulated cortex, thalamus and putamen. In both CTR/eAD and CTR/AD comparisons the largest rCBF reductions were found in functional regions including left (p<0.0001) and right (p<0.0001) temporo-parietal cortex and associative parietal cortex (p<0.0001). When eAD was compared to AD, this latter showed the largest reductions in right temporo-parietal cortex (p<0.0001) and in right prefrontal cortex (p<0.005). Conclusions. In this study the rCBF was investigated in early and severe Alzheimer's Disease taking into account the functional connectivity among brain regions. Our results confirm previous findings on the progression of

Geohydrological simulation of a deep coastal repository

International Nuclear Information System (INIS)

Follin, S.

1995-12-01

This conceptual-numerical study treats the dewatering and resaturation phases associated with the construction, use and closure of a coastal nuclear waste repository located at depth in sparsely fractured Baltic Shield rocks. The main objective is to simulate the extent and duration of saline intrusion for a reasonable set of geohydrological assumptions. Long-term changes in the chemical environment associated with saline intrusion may affect the properties of the buffer zone material (bentonite). The first part of the study deals with history matching of a simple model geometry and the second part treats the dewatering and resaturation phases of the simulated repository. The history matching supports the standpoint that the occurrence of saline ground water reflects an ongoing but incomplete Holocene flushing of the Baltic Shield. The drawdown after fifty years of dewatering is highly dependent on the permeability of the excavated damaged zone. If the permeability close the repository is unaltered the entire region between the top side of the model and the repository is more or less partially saturated at the end of the simulation period. The simulations of a fifty year long recovery period suggest that the distribution between fresh and saline ground waters may be quite close to the conditions prior to the dewatering phase already after fifty years of closure despite an incomplete pressure recovery, which is an interesting result considering the objective of the study. 12 refs

Rotary-Wing Brownout Mitigation: Technologies and Training (Remedes contre le phenomene de brownout sur les appareils a voilure tournante: Technologies et entrainement)

Science.gov (United States)

2012-01-01

thorstenwernereger@bundeswehr.org Mr. Peter KIELHORN EADS Deutschland GmbH P.O. Box 88039 Friedrichshafen E-mail: peter.kielhorn...Deutschland GmbH P.O. Box 88039 Friedrichshafen E-mail: thomas.muensterer@cassidian.com ISRAEL Mr. Ofer KLEIN Elbit Systems Aerospace Adv. Tech

A Study of an Effective Offsets Model for Korea

Science.gov (United States)

2013-12-01

Defense and Space EISD Excess Inventory Sales Division EU European Union FMS Foreign Military Sale ISDEFE Ingenieria de Sistemas para la Defensa de ...transfer, including aero-electronic software source code, components purchases, and logistics supply. When EADS recognized its lack of competitiveness

Aerospace Materials and Process Technology Reinvestment Workshop Held in Dayton, Ohio on 18-19 May 1993.

Science.gov (United States)

1993-05-19

The Laboratories Theory, Modeling and Simulation , • ATP Characterization J Education and Human Resources • MTC Facilities -- NBSR and CNRF MISSION...34 Automiated System for Composite Analysis (ASCA).Y -Basis for usefri(eadly numerical methods to describe composite laminates and predict ?heir response

Identification of host fruit volatiles from snowberry (Symphoricarpos albus), attractive to Rhagoletis zephyria flies from Western United States

Science.gov (United States)

Gas chromatography coupled with electroantennogram detection (GC-EAD) was used to identify volatiles from the fruit of Snowberry, Symphoricarpos albus laevigatus, as key attractants for Rhagoletis zephyria flies reared from snowberry fruit. A nine-component blend containing 3-methylbutan-1-ol (3%), ...

Volatiles from spruce trap-trees detected by Ips typographus bark beetles: chemical and electrophysiological analyses

Czech Academy of Sciences Publication Activity Database

Kalinová, Blanka; Břízová, Radka; Knížek, M.; Turčáni, M.; Hoskovec, Michal

2014-01-01

Roč. 8, č. 4 (2014), s. 305-316 ISSN 1872-8855 Institutional support: RVO:61388963 Keywords : Ips typographus * Picea abies * host selection * semiochemicals * GC-EAD * GC9GC/TOFMS Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.462, year: 2014

Dicty_cDB: SHD651 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available ead from insert in 3'HPRT insertion targeting and chromosome engineering clone MH...PP142o16. 50 0.13 1 CR044130 |CR044130.1 Forward strand read from insert in 3'HPRT insertion targeting and chromosome engineering

Application of Electro-Technologies in Processing of Flax Fiber

Directory of Open Access Journals (Sweden)

G. S. Vijaya Raghavan

2013-08-01

Full Text Available Flax fibers used for various applications are obtained from flax stems. Retting followed by drying and mechanical separation leads to the production of fibers. This review article discusses the application of electro-technologies in the production of bast fibers from the flax stem. In these technologies, flax stems harvested from the field are subjected to microwave assisted retting, followed by electro–osmotic dewatering which reduces the water content of the stems. Dewatered stems are transferred to a microwave chamber for further drying, thus retted stems are obtained for further processing.

Cost effective treatment for wet FGD scrubber bleedoff

Energy Technology Data Exchange (ETDEWEB)

Janecek, K.F. [EIMCO Process Equipment Company, Salt Lake City, UT (United States); Kim, J.Y. [Samkook Corporation, Seoul (Korea, Democratic People`s Republic of)

1994-12-31

The dewatering of scrubber bleedoff gypsum is a thoroughly proven technology, whether for production of wallboard grade gypsum or environmentally responsible land fill. Careful review of the technology options will show which one is the most effective for the specific plant site. Likewise, a recipe for wastewater treatment for heavy metals removal can be found that will meet local regulatory limits. EIMCO has worldwide experience in FGD gypsum sludge dewatering and wastewater treatment. Contacting EIMCO can be the most important step toward a practical cost effective system for handling FGD scrubber bleed slurries.

Host Plant Species Differentiation in a Polyphagous Moth: Olfaction is Enough.

Science.gov (United States)

Conchou, Lucie; Anderson, Peter; Birgersson, Göran

2017-08-01

Polyphagous herbivorous insects need to discriminate suitable from unsuitable host plants in complex plant communities. While studies on the olfactory system of monophagous herbivores have revealed close adaptations to their host plant's characteristic volatiles, such adaptive fine-tuning is not possible when a large diversity of plants is suitable. Instead, the available literature on polyphagous herbivore preferences suggests a higher level of plasticity, and a bias towards previously experienced plant species. It is therefore necessary to take into account the diversity of plant odors that polyphagous herbivores encounter in the wild in order to unravel the olfactory basis of their host plant choice behaviour. In this study we show that a polyphagous moth, Spodoptera littoralis, has the sensory ability to distinguish five host plant species using olfaction alone, this being a prerequisite to the ability to make a choice. We have used gas chromatography mass spectrometry (GC-MS) and gas chromatography electroantennographic detection (GC-EAD) in order to describe host plant odor profiles as perceived by S. littoralis. We find that each plant emits specific combinations and proportions of GC-EAD active volatiles, leading to statistically distinct profiles. In addition, at least four of these plants show GC-EAD active compound proportions that are conserved across individual plants, a characteristic that enables insects to act upon previous olfactory experiences during host plant choice. By identifying the volatiles involved in olfactory differentiation of alternative host plants by Spodoptera littoralis, we set the groundwork for deeper investigations of how olfactory perceptions translate into behaviour in polyphagous herbivores.

(Pop)kultura po rock and rollu. Uwagi o japońskiej muzyce eksperymentalnej

OpenAIRE

Brzostek, Dariusz

2014-01-01

The article discusses the history of Japanese experimental music as a confrontation between the traditional – even conservative – Japanese cultural values and the modern, or postmodern, artistic and social values of the experimental music influenced by jazz, rock and roll and American popular music. The early electronic works, post-jazz improvised music, free-form composition, avant-garde rock music, and electronic and electro-acoustic noise are music genres to which the rise of the Japanese ...

Poems of Wildness

OpenAIRE

Dubeau, Christian

2016-01-01

My research interests focus on the programmatic representation of the natural world and current environmental issues through acoustic and electro-acoustic music. Although I believe that music is an art that should creatively assert itself regardless of extra-musical associations, I find that the programmatic elements inspire listeners to evaluate the world with a fresh perspective. I aim to compose works that encourage my community to listen more closely to the world around them. While the...

On the Music of Sounds and the Music of Things (EMS2017, Nagoya, Japan)

OpenAIRE

Richards, John; Landy, Leigh

2017-01-01

After a century of great upheaval in music, the twenty-first century is demonstrating that it will provide electroacoustic (or sound-based) music with continued radical developments although they may very well be of a different sort. Technological developments certainly dictated most of the twentieth century changes in music and this influence is in no way decreasing. The key change is less in terms of radical change regarding content; instead, our thesis is that production and distribution w...

Disease: H00822 [KEGG MEDICUS

Lifescience Database Archive (English)

Full Text Available ead to childhood end-stage renal failure. Kidney disease UPK3A [HSA:7380] [KO:K19520] RET [HSA:5979] [KO:K05...cause human renal adysplasia leading to severe kidney failure. ... JOURNAL ... J Am Soc Nephrol 16:2141-9 (2005)

75 FR 33445 - U.S. Citizenship and Immigration Services Fee Schedule

Science.gov (United States)

2010-06-11

... comprehensive fee study and refined its cost accounting process, and determined that current fees do not recover... State. DNB--Dun and Bradstreet. EAD--Employment Authorization Document. FASAB--Federal Accounting... naturalization benefits and ensures the collection, safeguarding, and accounting of fees by USCIS. INA section...

Application of electro-osmosis to radioactive waste processing

International Nuclear Information System (INIS)

Turner, A.D.

1989-01-01

Electro-osmotic dewatering (EOD) is a remotely controllable process for the final stage of slurry concentration after gravity settling or filtration prior to immobilization in cement. It operates by using an electric field instead of pressure as the driving force across a microporous non-conducting membrane - partitioning the solid and liquid components by charge separation. The high solids retention factor (> 99.99%) yields decontamination factors > 1000. Dewatering of a wide range of suspensions can be accomplished at a variety of membranes - including fabrics (eg cotton) for LLW, and ceramics or glass for MLW. Volume reduction factors of 10 can be achieved for low conductivity streams. Planar and tubular membrane designs have been considered for compact full-scale plants. Cost-benefit analyses indicate that, in common with other techniques, large savings on immobilization and disposal costs (> 87%) can be made by this further dewatering stage after gravity settling prior to cementing. Estimates for EOD of capital and running costs amount to 2% and 1.3% respectively of the savings made over 10 years, with electrical power contributing only 0.15%. (author)

78 FR 17423 - Filing Procedures for Employment Authorization and Automatic Extension of Existing Employment...

Science.gov (United States)

2013-03-21

... (Form I-9) and E-Verify processes. DATES: The 6-month automatic extension of employment authorization... information on DED, including guidance on the application process for EADs and additional information on... for Certain Liberians Pursuant to his constitutional authority to conduct the foreign relations of the...

Analyses of volatiles produced by the African fruit fly species complex (Diptera, Tephritidae)

Czech Academy of Sciences Publication Activity Database

Břízová, Radka; Vaníčková, Lucie; Faťarová, M.; Ekesi, S.; Hoskovec, Michal; Kalinová, Blanka

-, č. 540 (2015), s. 385-404 ISSN 1313-2989 Institutional support: RVO:61388963 Keywords : Ceratitis FAR complex * chemotaxonomy * male and female-borne volatiles * GCxGC-TOFMS * GC-EAD Subject RIV: EG - Zoology Impact factor: 0.938, year: 2015 http://zookeys.pensoft.net/articles.php?id=6223

Josiah Willard Gibbs and his Ensembles

Indian Academy of Sciences (India)

statistical physics, Monte. Carlo methods, molecular dynamics, radiation .... w ith elastic theories and show ed unam biguously that the em piricalphenom ena in .... the probability of H eads b e p and of T ails b e q = 1 ¡ p. T he sam ple space ...

Beta Testing of Persistent Passive Acoustic Monitors

Science.gov (United States)

2012-10-01

three platforms provide the capability to work over a wide range of spatial and temporal scales. Hardware and software integration of the DMONs in...closely with Richard M. Ead (Sensors and Sonar Systems Department, Naval Undersea Warfare Center, NUWC Code 1535), Ted Ioannides (PS 4013) and Dave

The NATO STO Task Group AVT-201 on Extended Assessment of Stability and Control Prediction Methods for NATO Air Vehicles

Science.gov (United States)

2014-06-20

concentrated on SACCON. The planform and section profiles were defined in cooperation between DLR and EADS -MAS during the early stages of AVT-161. DLR...however most predictions were made as first-order temporal predictions. Given the highly unsteady flow fields observed by the experiments, unsteady

Amorphous SiC/c-ZnO-Based Quasi-Lamb Mode Sensor for Liquid Environments

Directory of Open Access Journals (Sweden)

Cinzia Caliendo

2017-05-01

Full Text Available The propagation of the quasi-Lamb modes along a-SiC/ZnO thin composite plates was modeled and analysed with the aim to design a sensor able to detect the changes in parameters of a liquid environment, such as added mass and viscosity changes. The modes propagation was modeled by numerically solving the system of coupled electro-mechanical field equations in three media. The mode shape, the power flow, the phase velocity, and the electroacoustic coupling efficiency (K2 of the modes were calculated, specifically addressing the design of enhanced-coupling, microwave frequency sensors for applications in probing the solid/liquid interface. Three modes were identified that have predominant longitudinal polarization, high phase velocity, and quite good K2: the fundamental quasi symmetric mode (qS0 and two higher order quasi-longitudinal modes (qL1 and qL2 with a dominantly longitudinal displacement component in one plate side. The velocity and attenuation of these modes were calculated for different liquid viscosities and added mass, and the gravimetric and viscosity sensitivities of both the phase velocity and attenuation were theoretically calculated. The present study highlights the feasibility of the a-SiC/ZnO acoustic waveguides for the development of high-frequency, integrated-circuit compatible electroacoustic devices suitable for working in a liquid environment.

Effects of drying methods on the low temperature reactivity of Victorian brown coal to oxygen

Energy Technology Data Exchange (ETDEWEB)

Unal, S.; Wood, D.G.; Harris, I.J. (University of Marmara, Istanbul (Turkey). Ataturk Faculty of Education, Division of Science Education)

1992-02-01

The effects of air drying and thermal dewatering on the low temperature oxygen reactivity of Victorian brown coal have been investigated in the temperature range 35-55{degree}C and at 100 kPa oxygen pressure using coal samples ground to {lt} 100 mesh. An attempt has also been made to relate the low temperature oxygen reactivity of the coal to its free radical concentration as measured prior to oxidation. Two rate models, the Schmidt and Winmill models, have been adapted to include the initial free radical concentration of the coal samples as the drying method sensitivity parameter in lieu of the concentration of oxygen-reactive sites in the coal material. The experimental results show that air drying, which reduces the free radical concentration of the coal, causes a decline in its oxygen reactivity whereas thermal dewatering, which causes an increase in the free radical concentration of the coal, enhances its oxygen reactivity. Air drying does not affect the distribution of the consumed oxygen in the oxidation products. A difference is observed in the case of the thermally dewatered coal samples. The correlation of the two rate models adopted is considered equally satisfactory. However, only the values obtained for the two activation energies in the Winmill model reflect the changes caused by thermal dewatering in the oxidation pattern of the coal. The activation energy values obtained from the two models are within the range of those quoted in the literature for the abstraction of hydrogen from various arene structures by free radicals. 35 refs., 10 figs., 8 tabs.

Study on air pollution monitoring in Korea using low volume air sampler by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Yong Sam Chung; Jong Hwa Moon, Young Ju Chung; Seung Yeon Cho; Sang Hun Kang

1999-01-01

The aim of this research was to enhance the use of nuclear analytical techniques for air pollution studies and to study the feasibility of the use of instrumental neutron activation analysis (INAA) as a routine monitoring tool to reveal environmental pollution sources. For the collection of air particulate samples, the Gent stacked filter unit, low volume sampler with Nucleopore membrane filters were used. Trace elements in samples collected at two suburban residential sites, Taejon and Wonju city in the Republic of Korea, were analyzed by INAA. Variations of the elemental concentrations were measured monthly and the enrichment factors were calculated for the fine (< 2 μm EAD) and coarse size (2-10 μm EAD) fractions. The analytical data were treated statistically to estimate the relationship between the two variables, the concentrations of elements and the total suspended particulate matter. The results were used to describe the emission source and their correlation. (author)

Male scent-marking pheromone of Bombus ardens ardens (Hymenoptera; Apidae) attracts both conspecific queens and males

Science.gov (United States)

Kubo, Ryohei; Harano, Ken-ichi; Ono, Masato

2017-10-01

To explore the role of the volatiles emitted from male labial gland (LG) of the bumblebee Bombus ardens ardens, we investigated the responses of virgin queens and males to volatiles using a gas chromatography-electroantennographic detector (GC-EAD) system and Y-tube olfactometer. GC-EAD analysis revealed that citronellol, the main compound detected in the male LG, caused clear electrophysiological responses in the antennae of B. a. ardens virgin queens and males although two minor compounds elicited antennal responses when applied in a high concentration. Behavioral tests using a Y-tube olfactometer showed that queens and males were significantly attracted to both LG extracts and citronellol more than to the solvent alone. This is the first study to demonstrate that citronellol as a major compound of male scent-marking pheromone in B. a. ardens functions as a sex attractant for queens. The results also suggest that this compound has another function as a trail marker used by males.

Person-Based Versus Generalized Impulsivity Disinhibition in Frontotemporal Dementia and Alzheimer Disease.

Science.gov (United States)

Paholpak, Pongsatorn; Carr, Andrew R; Barsuglia, Joseph P; Barrows, Robin J; Jimenez, Elvira; Lee, Grace J; Mendez, Mario F

2016-09-19

While much disinhibition in dementia results from generalized impulsivity, in behavioral variant frontotemporal dementia (bvFTD) disinhibition may also result from impaired social cognition. To deconstruct disinhibition and its neural correlates in bvFTD vs. early-onset Alzheimer's disease (eAD). Caregivers of 16 bvFTD and 21 matched-eAD patients completed the Frontal Systems Behavior Scale disinhibition items. The disinhibition items were further categorized into (1) "person-based" subscale which predominantly associated with violating social propriety and personal boundary and (2) "generalized-impulsivity" subscale which included nonspecific impulsive acts. Subscale scores were correlated with grey matter volumes from tensor-based morphometry on magnetic resonance images. In comparison to the eAD patients, the bvFTD patients developed greater person-based disinhibition (P dementia, violations of social propriety and personal boundaries involved fronto-parieto-temporal network of Theory of Mind, whereas nonspecific disinhibition involved the OFC and aTL. © The Author(s) 2016.

Competencias tecnológicas de los estudiantes de educación integral de la universidad nacional abierta

Directory of Open Access Journals (Sweden)

Yaristh Josefa Dávila Quiroz

2016-01-01

Full Text Available Esta ponencia tiene como objetivo exhibir la revisión documental preliminar de un estudio en desarrollo que busca determinar las Competencias Tecnológicas de los estudiantes de Educación Integral de la Universidad Nacional Abierta (UNA. En este referente teórico se describen aspectos relevantes sobre las Tecnologías de Información y Comunicación (TIC en el contexto educativo, la Educación a Distancia (EaD, las TIC en la UNA y las competencias tecnológicas de los estudiantes. Se concluye que las TIC juegan un papel fundamental en EaD donde los medios tecnológicos son indispensables en la interacción con otras personas y con la información. Es necesario determinar las competencias tecnológicas de los estudiantes de educación integral para identificar fortalezas y debilidades, así como sus necesidades de formación.

Sexual communication in the termite Prorhinotermes simplex (Isoptera, Rhinotermitidae) mediated by a pheromone from female tergal glands

Czech Academy of Sciences Publication Activity Database

Hanus, Robert; Luxová, Anna; Šobotník, Jan; Kalinová, Blanka; Jiroš, Pavel; Křeček, J.; Bourguignon, T.; Bordereau, Ch.

2009-01-01

Roč. 56, č. 2 (2009), s. 111-118 ISSN 0020-1812 R&D Projects: GA AV ČR IAA600550614 Institutional research plan: CEZ:AV0Z40550506 Keywords : sex pheromone * Prorhinotermes * GC-EAD * tergal glands * dodecatrienol Subject RIV: CC - Organic Chemistry Impact factor: 1.480, year: 2009

Engineer Analysis of the Light Infantry Division (ELID). Volume 1

Science.gov (United States)

1986-12-01

m 5. Forward logistics protection a. FARP b. Brigade petroleum, oil , and lubricant (POL) berms P P *Positlon may not be dug in if...battalion in order to complete all of the squad and equipment corabat- essencial requirements. With Che adrittion of the EAD force, there is a large

The effect of hydroxylation on CNT to form Chitosan-CNT composites: A DFT study

International Nuclear Information System (INIS)

Yu, Rui; Ran, Maofei; Wen, Jie; Sun, Wenjing; Chu, Wei; Jiang, Chengfa; He, Zhiwei

2015-01-01

Graphical abstract: - Highlights: • The effect of hydroxylation on CNT to form Chitosan-CNT composites was studied. • The adsorption of Chitosan on CNTs is very weak by electrostatic interactions. • Chitosan loads onto CNT-OH_n via hydrogen-bond interactions. • Chitosan transfers electron to CNT-OH_n and thus improves the reactivity of CNT. - Abstract: The effect of types of CNTs (pristine and hydroxylated) on the synthesis of Chitosan-CNT (CS-CNT) composites was investigated theoretically. The adsorption energy (E_a_d_s) of CS on the pristine CNT and hydroxylated CNTs (CNT-OH_n, n = 1–6) as well as the structural and electronic properties of said composites have been investigated. Results show that the adsorption of CS on CNT and CNT-OH_n is thermodynamically favored. The E_a_d_s of CS on CNTs was calculated to be −20.387 kcal/mol from electrostatic interactions. For CS adsorbed into CNT-OH_n, E_a_d_s ranges from −20.612 to −37.567 kcal/mol. Hydroxyl groups on CNT are the main adsorption sites for CS loading onto CNT-OH_n via hydrogen-bond interactions. The CS-CNT-OH_3 is the most sable composite among tested complexes. The energy gap (ΔE_g_a_p) of CS-CNT-OH_3 was calculated less than pristine CNT and CNT-OH_3, indicative of the composites being more reactive than that of pristine CNTs and CNT-OH_3. It was proved that CS can transfer electron to the hydroxylated CNTs, thus overcoming the drawbacks of CNTs being chemically inert.

Educação a distância: uma análise estatística dos fatores relacionados à evasão e à permanência

Directory of Open Access Journals (Sweden)

Ricardo Antonio Cornelio

2016-12-01

Full Text Available O maior desafio que as organizações enfrentam nos dias atuais está relacionado à adoção de medidas adequadas para lidar com a grande velocidade de inovação. A Educação a Distância (EaD, com a utilização das novas tecnologias de informação e comunicação (TICs, tem viabilizado o acesso a um número cada vez maior de sujeitos. Uma das vantagens frequentemente citada da EaD é permitir ao aluno estudar onde quer que esteja e quando lhe for mais conveniente. Junte-se a essa liberdade a utilização de computadores cada vez mais velozes e o desenvolvimento de novos aplicativos, propiciando o crescimento da educação a distância. Entretanto, essa expansão e o uso das tecnologias, por si só, não são capazes de evitar a ocorrência de evasão. Evitar o aumento da evasão e levantar as suas causas é atividade relevante para as instituições que tenham a capacidade de dar apoio aos estudantes durante o desenvolvimento de seu curso. Para identificar as questões que mais retratam as facilidades e dificuldades enfrentadas pelo alunado em cursos EaD, optou-se pela técnica da Análise Fatorial Exploratória, aplicada em duas categorias de alunos, uma delas constituída pelos alunos matriculados e alunos formados e a outra categoria composta de alunos que abandonaram o curso em um polo de apoio presencial do município de Itabira – MG.

Impact of real-time metabolomics in liver transplantation: Graft evaluation and donor-recipient matching.

Science.gov (United States)

Faitot, Francois; Besch, Camille; Battini, Stephanie; Ruhland, Elisa; Onea, Mihaela; Addeo, Pietro; Woehl-Jaeglé, Marie-Lorraine; Ellero, Bernard; Bachellier, Philippe; Namer, Izzie-Jacques

2017-12-02

There is an emerging need to assess the metabolic state of liver allografts especially in the novel setting of machine perfusion preservation and donor in cardiac death (DCD) grafts. High-resolution magic-angle-spinning nuclear magnetic resonance (HR-MAS-NMR) could be a useful tool in this setting as it can extemporaneously provide untargeted metabolic profiling. The purpose of this study was to evaluate the potential value of HR-MAS-NMR metabolomic analysis of back-table biopsies for the prediction of early allograft dysfunction (EAD) and donor-recipient matching. The metabolic profiles of back-table biopsies obtained by HR-MAS-NMR, were compared according to the presence of EAD using partial least squares discriminant analysis. Network analysis was used to identify metabolites which changed significantly. The profiles were compared to native livers to identify metabolites for donor-recipient matching. The metabolic profiles were significantly different in grafts that caused EAD compared to those that did not. The constructed model can be used to predict the graft outcome with excellent accuracy. The metabolites showing the most significant differences were lactate level >8.3 mmol/g and phosphocholine content >0.646 mmol/g, which were significantly associated with graft dysfunction with an excellent accuracy (AUROC lactates  = 0.906; AUROC phosphocholine  = 0.816). Native livers from patients with sarcopenia had low lactate and glycerophosphocholine content. In patients with sarcopenia, the risk of EAD was significantly higher when transplanting a graft with a high-risk graft metabolic score. This study underlines the cost of metabolic adaptation, identifying lactate and choline-derived metabolites as predictors of poor graft function in both native livers and liver grafts. HR-MAS-NMR seems a valid technique to evaluate graft quality and the consequences of cold ischemia on the graft. It could be used to assess the efficiency of graft resuscitation on

No nuclear safety without security

International Nuclear Information System (INIS)

Anon.

2016-01-01

ead of Health and Safety - Nuclear Safety and Corporate Security at ENGIE Benelux, Pierre Doumont has the delicate job of defining and implementing measures, including cybersecurity, to prevent the risk of malevolent acts against tangible and intangible assets. He gives some hints on the contribution of nuclear security to safety.

[Improvement of municipal sewage sludge dewaterability by bioleaching: a pilot-scale study with sequence batch reaction model].

Science.gov (United States)

Liu, Fen-Wu; Zhou, Li-Xiang; Zhou, Jun; Jiang, Feng; Wang, Dian-Zhan

2011-07-01

To observe the bioleaching effect on sewage sludge dewaterability, three consecutive batch bioleaching experiments were conducted through a bioleaching bio-reactor with 700 L of working volume. Subsequently, the bioleached sludge was dewatered by using chamber filter press. The results show that the 1st batch bioleaching process can be finished within 90 hours if the aeration amount was 1.2 m3/h with the 1: 15 mixing ratio of bioleached sludge to raw sludge. The pH of sludge declines from initial 6.11 to 2.33 while ORP increased from initial -134 mV to finial 507 mV. The specific resistance to filtration (SRF) of the tested sludge was decreased from original 1.00 x 10(13) m/kg to final 0.09 x 10(13) m/kg after bioleaching. For the subsequent two batch trials, the bioleaching process can be finished in 40 hours and 46 hours, respectively. Likewise, sludge SRF is also significantly decreased to 0.19 x 10(13) m/kg and 0.36 x 10(13) m/kg if the mixing ratio of bioleached sludge to fresh sludge is 1:1 although the microbial nutrient substance dosage is reduced by 25% and 50% for 2nd, and 3rd batch experiments, respectively. The harvested bioleached sludge from three batch trails is dewatered by chamber filter press with 0.3-0.4 MPa working pressure for 2 hours. It is found that the moisture of dewatered sludge cake can be reduced to 58%, and that the dewatered sludge cake is of khaki appearance and didn't emit any offensive odor. In addition, it is also observes that sludge organic matter only changed a bit from 52.9% to 48.0%, but 58% of sludge-borne Cu and 88% of sludge-borne Zn can be removed from sludge by bioleaching process. Therefore, dual goals for sludge-borne heavy metal removal and sludge dewatering of high efficiency can be achieved simultaneously through the approach mentioned above. Therefore, bioleaching technique is of great engineering application for the treatment of sewage sludge.

Post-anaerobic digestion thermal hydrolysis of sewage sludge and food waste: Effect on methane yields, dewaterability and solids reduction.

Science.gov (United States)

Svensson, Kine; Kjørlaug, Oda; Higgins, Matthew J; Linjordet, Roar; Horn, Svein J

2018-04-01

Post-anaerobic digestion (PAD) treatment technologies have been suggested for anaerobic digestion (AD) to improve process efficiency and assure hygenization of organic waste. Because AD reduces the amount of organic waste, PAD can be applied to a much smaller volume of waste compared to pre-digestion treatment, thereby improving efficiency. In this study, dewatered digestate cakes from two different AD plants were thermally hydrolyzed and dewatered, and the liquid fraction was recirculated to a semi-continuous AD reactor. The thermal hydrolysis was more efficient in relation to methane yields and extent of dewaterability for the cake from a plant treating waste activated sludge, than the cake from a plant treating source separated food waste (SSFW). Temperatures above 165 °C yielded the best results. Post-treatment improved volumetric methane yields by 7% and the COD-reduction increased from 68% to 74% in a mesophilic (37 °C) semi-continuous system despite lowering the solid retention time (from 17 to 14 days) compared to a conventional system with pre-treatment of feed substrates at 70 °C. Results from thermogravimetric analysis showed an expected increase in maximum TS content of dewatered digestate cake from 34% up to 46% for the SSFW digestate cake, and from 17% up to 43% in the sludge digestate cake, after the PAD thermal hydrolysis process (PAD-THP). The increased dewatering alone accounts for a reduction in wet mass of cake leaving the plant of 60% in the case of sludge digestate cake. Additionaly, the increased VS-reduction will contribute to further reduce the mass of wet cake. Copyright © 2018 Elsevier Ltd. All rights reserved.

Electroacoustic Process Study of Plasma Sparker Under Different Water Depth

KAUST Repository

Huang, Yifan; Zhang, Liancheng; Zhang, Xuming; Li, Shuran; Liu, Zhen; Yan, Keping

2015-01-01

Fourier transform (FFT) results show that the dominant energy is around 20 kHz, which is mainly induced by the expansion pulse and its oscillation. According to the simulation results, the fundamental frequency of the acoustic waveform increases

Electroacoustic Process Study of Plasma Sparker Under Different Water Depth

KAUST Repository

Huang, Yifan

2015-01-05

The plasma sparker has been applied in oceanic high-resolution seismic exploration for decades. Normally it is towed on the water surface. This is suitable for shallow water, but if the water depth is great, the resolution will decrease dramatically, especially in the horizontal direction. This paper proposes the concept of a deep-towed plasma sparker and presents an experimental study of plasma sparker performance in terms of electric parameters, bubble behavior, and acoustic characteristics. The results show that hydrostatic pressure at a source depth ranging from 1 to 2000 m has a negligible influence on the electric parameters but a strong influence on bubble behavior, wherein both the maximum bubble radius and oscillation period are decreased. The collapse pulse vanishes when the source depth reaches 1000 m or deeper, and no bubble oscillation can be distinguished. The source level (evaluated by the expansion pulse) is also decreased as the source depth increases; moreover, the greater the discharge energy, the smaller the source level loss. The discharge energy per electrode should be greater than 20 J for the deep-towed plasma sparker, which can make the source level loss induced by hydrostatic pressure smaller than the transmission loss. The fast Fourier transform (FFT) results show that the dominant energy is around 20 kHz, which is mainly induced by the expansion pulse and its oscillation. According to the simulation results, the fundamental frequency of the acoustic waveform increases with source depth in accord with a log linear trend, and also reaches tens of kilohertz in deep water. So, before the development of deep-towed plasma sparker, a new technical solution will need to be developed to solve this problem. © 1976-2012 IEEE.

Electroacoustics modeling of piezoelectric welders for ultrasonic additive manufacturing processes

Science.gov (United States)

Hehr, Adam; Dapino, Marcelo J.

2016-04-01

Ultrasonic additive manufacturing (UAM) is a recent 3D metal printing technology which utilizes ultrasonic vibrations from high power piezoelectric transducers to additively weld similar and dissimilar metal foils. CNC machining is used intermittent of welding to create internal channels, embed temperature sensitive components, sensors, and materials, and for net shaping parts. Structural dynamics of the welder and work piece influence the performance of the welder and part quality. To understand the impact of structural dynamics on UAM, a linear time-invariant model is used to relate system shear force and electric current inputs to the system outputs of welder velocity and voltage. Frequency response measurements are combined with in-situ operating measurements of the welder to identify model parameters and to verify model assumptions. The proposed LTI model can enhance process consistency, performance, and guide the development of improved quality monitoring and control strategies.

Human and automatic speaker recognition over telecommunication channels

CERN Document Server

Fernández Gallardo, Laura

2016-01-01

This work addresses the evaluation of the human and the automatic speaker recognition performances under different channel distortions caused by bandwidth limitation, codecs, and electro-acoustic user interfaces, among other impairments. Its main contribution is the demonstration of the benefits of communication channels of extended bandwidth, together with an insight into how speaker-specific characteristics of speech are preserved through different transmissions. It provides sufficient motivation for considering speaker recognition as a criterion for the migration from narrowband to enhanced bandwidths, such as wideband and super-wideband.

Electron-phonon coupling effect on wakefields in piezoelectric semiconductors

International Nuclear Information System (INIS)

Salimullah, M; Shukla, P K; Ghosh, S K; Nitta, H; Hayashi, Y

2003-01-01

Using an appropriate dielectric constant for an n-type piezoelectric semiconductor plasma and a moving test particle approach, it is shown that, besides the usual screened potential, there exists a non-Coulombian oscillatory potential or a wakefield behind a moving charged particle due to a strong resonant interaction between the charged particle and the electro-acoustic mode of the host semiconductor. With the concept of the wakefield, a possible lattice formation of colloids resulting from ion implantation in a current-carrying piezoelectric semiconductor has been examined

Enhancing engagement in multimodality environments by sound movement in a virtual space

DEFF Research Database (Denmark)

Götzen, Amalia De

2004-01-01

of instrumental sounds - has allowed space as a musical instrumental practice to flourish. Electro-acoustic technologies let composers explore new listening dimensions and consider the sounds coming from loudspeakers as possessing different logical meanings from the sounds produced by traditional instruments....... Medea, Adriano Guarnieri's "video opera", is an innovative work stemming from research in multimedia that demonstrates the importance and amount of research dedicated to sound movement in space. Medea is part of the Multi-sensory Expressive Gesture Application project (http://www.megaproject.org). Among...

The measurement of water transport in porous materials using impedance spectroscopy

International Nuclear Information System (INIS)

Ball, R J; Allen, G C

2010-01-01

This paper describes the application of electrical measurements to monitor the extraction (movement of water from the mortar) of water from calcium lime, natural hydraulic lime and Portland cement mortars placed on an adsorbent brick substrate. Impedance measurements were used to identify the changes in bulk resistance of the mortar. A model has been developed combining sharp front theory and Boltzmann's distribution law of statistical thermodynamics to identify the point at which no further absorption of water into the brick occurs. A linear relationship was found between the exponential of bulk resistance and the square root of time during dewatering. A change in gradient was attributed to the end of dewatering.

International Metadata Initiatives: Lessons in Bibliographic Control.

Science.gov (United States)

Caplan, Priscilla

This paper looks at a subset of metadata schemes, including the Text Encoding Initiative (TEI) header, the Encoded Archival Description (EAD), the Dublin Core Metadata Element Set (DCMES), and the Visual Resources Association (VRA) Core Categories for visual resources. It examines why they developed as they did, major point of difference from…

Martin Skancke : kõigepealt on vaja parandada pangandussüsteemi / Martin Skancke ; interv. Mikk Salu

Index Scriptorium Estoniae

Skancke, Martin

2008-01-01

Norra valitsuse pensionifondi juht vastab küsimustele, mis on praeguse ülemaailmse finantskriisi põhjused, kuidas ülemaailmsest surutisest välja tulla, kui palju on Norra pensionifond sel aastal oma väärtust kaotanud, miks on Boeingusse või EADS-i investeerimine tema arvates ebaeetiline. Lisa: Martin Skancke - hiigelfondi juht

77 FR 59943 - Extension of the Designation of Haiti for Temporary Protected Status

Science.gov (United States)

2012-10-01

... want an EAD, you must pay the Application for Employment Authorization (Form I-765) fee only if you are... you about your continued employment authorization once January 22, 2013 is reached in order to meet... not need a new document in order to reverify your employment authorization until after July 22, 2013...

[Digitalization study of sonotubometry device].

Science.gov (United States)

Li, Yang; Chen, Shu; Xu, Li; Nong, Dongxiao; Tang, Anzhou; Zhang, Zhiwei

2014-06-01

Sonotubometry is wildly used in developed countries, offers a easy, versatile and objective way to assess the function of Eustachian tube. The objectives of this study are to develop a low-cost digitalized device. The digitalized sonotubometry device was made of a personal computer with sound input and output accessories. The PC sound card, connected to a signal amplifier, exported probe band noise, while feedback sound was collected by a microphone. All 36 volunteers (72 ears) were involved in the sonotubometry test with JK-04A and CHN-08, in the conditions of dry-swallowing and wet-swallowing. The data were statistically analyzed using SPSS 13.0. The basic electroacoustic performance of the CHN-08 was acceptable. CHN-08 (7 kHz) detection and JK-04A consistency of kappa index was 0.472; CHN-08 (8 kHz) and JK-04A consistency of kappa index was 0.487; CHN-08 (7 kHz) and CHN-08 (8 kHz) consistency of kappa index was 0.688.Under the JK-04A, CHN-08 (7 kHz) and CHN-08 (8 kHz) three setups, Eustachian tube opening frequency was significantly lower for wet-swallowing than dry-swallowing, P digitalized sonotubometry is successfully developed. Its electroacoustic performance proved acceptable by authority assessments. The detection rate of CHN-08 is in accordance with that of JK-04A moderately. The study revealed that Eustachian tube is opened more easily by dry-swallowing than by wet-swallowing.

The Planck Telescope reflectors

Science.gov (United States)

Stute, Thomas

2004-09-01

The mechanical division of EADS-Astrium GmbH, Friedrichshafen is currently engaged with the development, manufacturing and testing of the advanced dimensionally stable composite reflectors for the ESA satellite borne telescope Planck. The objective of the ESA mission Planck is to analyse the first light that filled the universe, the cosmic microwave background radiation. Under contract of the Danish Space Research Institute and ESA EADS-Astrium GmbH is developing the all CFRP primary and secondary reflectors for the 1.5-metre telescope which is the main instrument of the Planck satellite. The operational frequency ranges from to 25 GHz to 1000 GHz. The demanding high contour accuracy and surface roughness requirements are met. The design provides the extreme dimensional stability required by the cryogenic operational environment at around 40 K. The elliptical off-axis reflectors display a classical lightweight sandwich design with CFRP core and facesheets. Isostatic mounts provide the interfaces to the telescope structure. Protected VDA provides the reflecting surface. The manufacturing is performed at the Friedrichshafen premises of EADS-Space Transportation GmbH, the former Dornier composite workshops. Advanced manufacturing technologies like true angle lay-up by CNC fibre placement and filament winding are utilized. The protected coating is applied at the CAHA facilities at the Calar Alto Observatory, Spain. The exhaustive environmental testing is performed at the facilities of IABG, Munich (mechanical testing) and for the cryo-optical tests at CSL Liege. The project is in advanced state with both Qualification Models being under environmental testing. The flight models will be delivered in 2004. The paper gives an overview over the requirements and the main structural features how these requirements are met. Special production aspects and available test results are reported.

Effects of interleukin-8 on estradiol and progesterone production by bovine granulosa cells from large follicles and progesterone production by luteinizing granulosa cells in culture.

Science.gov (United States)

Shimizu, Takashi; Kaji, Ayami; Murayama, Chiaki; Magata, Fumie; Shirasuna, Koumei; Wakamiya, Kaori; Okuda, Kiyoshi; Miyamoto, Akio

2012-01-01

Interleukin 8 (IL-8) is a chemoattractant involved in the recruitment and activation of neutrophils and is associated with the ovulate process. We examined the possible role of IL-8 in steroid production by bovine granulosa cells before and after ovulation. The concentration of IL-8 in the follicular fluid of estrogen-active dominant (EAD) and pre-ovulatory follicles (POF) was higher than that of small follicles (SF). CXCR1 mRNA expression was higher in the granulosa cells of EAD and POF than that of SF. In contrast, CXCR2 mRNA expression was lower in granulosa cells of EAD and POF than in SF. IL-8 inhibited estradiol (E2) production in follicle-stimulating hormone (FSH)-treated granulosa cells at 48 h of culture. IL-8 also suppressed CYP19A1 mRNA expression in FSH-treated granulosa cells. IL-8 stimulated progesterone (P4) production in luteinizing hormone (LH)-treated granulosa cells at 48 h of culture. Although IL-8 did not alter the expression of genes associated with P4 production, it induced StAR protein expression in LH-treated granulosa cells. The expression of CXCR1 mRNA in corpus luteum (CL) did not change during the luteal phase. In contrast, the expression of CXCR2 mRNA in middle CL was significantly higher than in early and regression CL during the luteal phase. In luteinizing granulosa cells, an in vitro model of granulosa cell luteinization, CXCR2 mRNA expression was downregulated, whereas CXCR1 mRNA expression was unchanged. IL-8 also stimulated P4 production in luteinizing granulosa cells. These data provide evidence that IL-8 functions not only as a chemokine, but also act as a regulator of steroid synthesis in granulosa cells to promote luteinization after ovulation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Availability of human induced pluripotent stem cell-derived cardiomyocytes in assessment of drug potential for QT prolongation

International Nuclear Information System (INIS)

Nozaki, Yumiko; Honda, Yayoi; Tsujimoto, Shinji; Watanabe, Hitoshi; Kunimatsu, Takeshi; Funabashi, Hitoshi

2014-01-01

Field potential duration (FPD) in human-induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs), which can express QT interval in an electrocardiogram, is reported to be a useful tool to predict K + channel and Ca 2+ channel blocker effects on QT interval. However, there is no report showing that this technique can be used to predict multichannel blocker potential for QT prolongation. The aim of this study is to show that FPD from MEA (Multielectrode array) of hiPS-CMs can detect QT prolongation induced by multichannel blockers. hiPS-CMs were seeded onto MEA and FPD was measured for 2 min every 10 min for 30 min after drug exposure for the vehicle and each drug concentration. I Kr and I Ks blockers concentration-dependently prolonged corrected FPD (FPDc), whereas Ca 2+ channel blockers concentration-dependently shortened FPDc. Also, the multichannel blockers Amiodarone, Paroxetine, Terfenadine and Citalopram prolonged FPDc in a concentration dependent manner. Finally, the I Kr blockers, Terfenadine and Citalopram, which are reported to cause Torsade de Pointes (TdP) in clinical practice, produced early afterdepolarization (EAD). hiPS-CMs using MEA system and FPDc can predict the effects of drug candidates on QT interval. This study also shows that this assay can help detect EAD for drugs with TdP potential. - Highlights: • We focused on hiPS-CMs to replace in vitro assays in preclinical screening studies. • hiPS-CMs FPD is useful as an indicator to predict drug potential for QT prolongation. • MEA assay can help detect EAD for drugs with TdP potentials. • MEA assay in hiPS-CMs is useful for accurately predicting drug TdP risk in humans

Availability of human induced pluripotent stem cell-derived cardiomyocytes in assessment of drug potential for QT prolongation

Energy Technology Data Exchange (ETDEWEB)

Nozaki, Yumiko, E-mail: yumiko-nozaki@ds-pharma.co.jp [Preclinical Research Laboratories, Dainippon Sumitomo Pharma. Co., Ltd., Suita, Osaka 564-0053 (Japan); Honda, Yayoi, E-mail: yayoi-honda@ds-pharma.co.jp [Preclinical Research Laboratories, Dainippon Sumitomo Pharma. Co., Ltd., Suita, Osaka 564-0053 (Japan); Tsujimoto, Shinji, E-mail: shinji-tsujimoto@ds-pharma.co.jp [Regenerative and Cellular Medicine Office, Dainippon Sumitomo Pharma. Co., Ltd., Chuo-ku, Tokyo 104-0031 (Japan); Watanabe, Hitoshi, E-mail: hitoshi-1-watanabe@ds-pharma.co.jp [Preclinical Research Laboratories, Dainippon Sumitomo Pharma. Co., Ltd., Suita, Osaka 564-0053 (Japan); Kunimatsu, Takeshi, E-mail: takeshi-kunimatsu@ds-pharma.co.jp [Preclinical Research Laboratories, Dainippon Sumitomo Pharma. Co., Ltd., Suita, Osaka 564-0053 (Japan); Funabashi, Hitoshi, E-mail: hitoshi-funabashi@ds-pharma.co.jp [Preclinical Research Laboratories, Dainippon Sumitomo Pharma. Co., Ltd., Suita, Osaka 564-0053 (Japan)

2014-07-01

Field potential duration (FPD) in human-induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs), which can express QT interval in an electrocardiogram, is reported to be a useful tool to predict K{sup +} channel and Ca{sup 2+} channel blocker effects on QT interval. However, there is no report showing that this technique can be used to predict multichannel blocker potential for QT prolongation. The aim of this study is to show that FPD from MEA (Multielectrode array) of hiPS-CMs can detect QT prolongation induced by multichannel blockers. hiPS-CMs were seeded onto MEA and FPD was measured for 2 min every 10 min for 30 min after drug exposure for the vehicle and each drug concentration. I{sub Kr} and I{sub Ks} blockers concentration-dependently prolonged corrected FPD (FPDc), whereas Ca{sup 2+} channel blockers concentration-dependently shortened FPDc. Also, the multichannel blockers Amiodarone, Paroxetine, Terfenadine and Citalopram prolonged FPDc in a concentration dependent manner. Finally, the I{sub Kr} blockers, Terfenadine and Citalopram, which are reported to cause Torsade de Pointes (TdP) in clinical practice, produced early afterdepolarization (EAD). hiPS-CMs using MEA system and FPDc can predict the effects of drug candidates on QT interval. This study also shows that this assay can help detect EAD for drugs with TdP potential. - Highlights: • We focused on hiPS-CMs to replace in vitro assays in preclinical screening studies. • hiPS-CMs FPD is useful as an indicator to predict drug potential for QT prolongation. • MEA assay can help detect EAD for drugs with TdP potentials. • MEA assay in hiPS-CMs is useful for accurately predicting drug TdP risk in humans.

O papel do tutor em cursos de educação a distância: competências e habilidades

Directory of Open Access Journals (Sweden)

Ana Maria Araújo Passos de Oliveira

2014-02-01

Full Text Available O papel profissional do tutor em cursos em EAD deve ser concebido como o conjunto de condições necessárias para o processo de ensino-aprendizagem à distância. Diante desse contexto, este trabalho tem como objetivo conhecer as competências e as habilidades necessárias ao papel do Tutor em cursos à distância. Para alcançar o objetivo proposto, utilizou-se do deli-neamento exploratório, através de pesquisa bibliográfica em que foram analisadas as conside-rações sobre a EAD, o sistema de tutoria e o papel do Tutor em cursos a distância, bem como a formação necessária para essa função. A partir da análise dos resultados, concluiu-se que o conjunto básico das competências e as habilidades necessárias que caracterizam o papel do tutor em cursos EAD são: possuir habilidades de comunicação, liderança, dinamismo, iniciativa, entusiasmo, criatividade, participação, motivação, competência interpessoal e de trabalho em equipe, além de comprometimento com a formação dos alunos, agilidade no atendimento ao aluno, proporcionando feedback das atividades, conhecer a organização pedagógica, adminis-trativa do curso e ter uma formação condizente com as atividades que irá desenvolver. Por isso, além de uma formação acadêmica em nível de graduação e pós-graduação, ele deve ter cursos específicos na área da Educação à Distância.