WorldWideScience

Sample records for bedding and linens

  1. Evaluation of Whiteness in Linen and Semi-linen Fabrics

    Directory of Open Access Journals (Sweden)

    Liucina Kot

    2015-03-01

    Full Text Available Whiteness of textiles is one of the main "white" product quality indicators described by the following parameters: lightness of a colour, colour tone (white shade, white uniformity and stability under the influence of physical factors. “White” textile products can be perceived by comparing them with a white standard (Pantone colour palette. On the other hand, the whiteness of the fabric can be estimated using the colorimeter and determining lightness of a fabric L. The purpose of a research is to assess the whiteness of a linen and semi-linen fabric using two different methods, to carry out a comparative analysis of the results and to associate fabric whiteness with the fabric structure parameters. Two methods were used for experiment (colorimeter Spectraflash SF450X and expert assessment of whiteness. The analysed colours of a fabric were divided into five colours: white, whitish, light grey, grey and dark grey. The examination of the two methods, different results were obtained: testing with colorimeter, white colour was found in only one fabric, while the experts found the fabrics of white colour much more. The opinions of experts vary also. Fabric lightness L was associated with fabric structure parameters – the warp and weft settings and fabric weave. It was found that these fabric structure parameters affect the lightness of a colour of a fabric L very little.DOI: http://dx.doi.org/10.5755/j01.ms.21.1.5348

  2. China Linen Signs Agreement to Ship Fabric to Italy

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    China Linen Textile Industry, Ltd. a China-based company engaged in the production and sale of linen yarn and various types of linen fabric, announced that its wholly-owned subsidiary, Heilongjiang Lanxi Sunrise

  3. Influence of Industrial Washing and Cyclic Fatigue on Slippage of Linen Fabric Threads along the Seam

    Directory of Open Access Journals (Sweden)

    Irina KORUNČAK

    2014-04-01

    Full Text Available All seams of garments shall withstand the established force effect in the longitudinal and transverse directions. Resistance to thread slippage along the seam is a major property of fabrics that is regulated by strict guidelines. In many research works, lining fabrics are chosen as the object of research as thread slippage is the most typical of them. What concerns the reports exploring slippage of linen fabric threads along the seam, just very few papers are available. Studies dealing with the influence made by industrial washing and cyclic load on the defect under investigation, thereby taking into account operational properties of garments are not readily available at all. The objective of the paper is to define the influence of industrial washing and cyclic tensile on slippage of linen fabric threads along the seam. For the research, five 100 % linen fabrics of plain weave have been selected. Control test specimens, unwashed and processed with different washing methods, have been analysed. Cyclic tensile of the test specimens has been carried out by a tensile machine “Tinius Olsen” at tensile force P = 20 N, tensile speed of 12.55 mm/s, number of cycles of 100. The carried-out testing has demonstrated that industrial washing decreased resistance of linen fabrics to thread slippage along the seam in the most cases. Analysis of the results obtained has shown that cyclic tensile led to particularly significant increase in the seam gap. DOI: http://dx.doi.org/10.5755/j01.ms.20.1.2486

  4. The effect of thermal aging and color pigments on the Egyptian linen properties evaluated by physicochemical methods

    Science.gov (United States)

    El-Gaoudy, H.; Kourkoumelis, N.; Varella, E.; Kovala-Demertzi, D.

    2011-11-01

    Archaeologists in Egypt discovered ancient colored textiles in great quantities in comparison with the analogous uncolored ones. Furthermore, the latter are far more deteriorated. Most research investigations into archaeological linen have been concerned with manufacture, restoration, and conservation but little information is available about the properties of the fibers, and particularly their chemical and physical properties after dyeing with natural dyes or painted with pigments. The aim of this study is to evaluate the physicochemical properties of Egyptian linen textiles coloring with a variety of pigments used in painting in ancient times after thermally aged to get linen samples which are similar as possible to the ancient linen textiles. The evaluations were based on Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction and tensile strength, and elongation measurements. Results showed that beyond cosmetic reasons, colored textiles did indeed play a role as protecting agents affecting strength and reducing thermal deterioration. Specifically, in the molecular level, pigments under study seem to interact to cellulose and lignin compounds of the aged linen while in the macroscopic level tensile and elongation parameters are altered. Electron microscopy confirms that pigment particles are deposited on and between the fibers' surfaces.

  5. Catabolism of volatile sulfur compounds precursors by Brevibacterium linens and Geotrichum candidum, two microorganisms of the cheese ecosystem.

    Science.gov (United States)

    Arfi, Kenza; Amárita, Felix; Spinnler, Henry-Eric; Bonnarme, Pascal

    2003-11-01

    Two Brevibacterium linens strains and the cheese-ripening yeast Geotrichum candidum were compared with regard to their ability to produce volatile sulfur compounds (VSCs) from three different precursors namely L-methionine, 4-methylthio-2-oxobutyric acid (KMBA) and 4-methylthio-2-hydroxybutyric acid (HMBA). All microorganisms were able to convert these precursors to VSCs. However, although all were able to produce VSCs from L-methionine, only G. candidum accumulated KMBA when cultivated on this amino acid, contrary to B. linens suggesting that the transamination pathway is not active in this microorganism. Conversely, a L-methionine gamma-lyase activity--which catalyses the one step L-methionine to methanethiol (MTL) degradation route--was only found in B. linens strains. Several other enzymatic activities involved in the catabolism of the precursors tested were investigated. KMBA transiently accumulated in G. candidum cultures, and was then reduced to HMBA by a KMBA dehydrogenase (KDH) activity. This activity was not detected in B. linens. Despite no HMBA dehydrogenase (HDH) was found in G. candidum, a strong HMBA oxidase (HOX) activity was measured in this microorganism. This latter activity was weakly active in B. linens. KMBA and HMBA demethiolating activities were found in all the microorganisms. Our results illustrate the metabolic diversity between cheese-ripening microorganisms of the cheese ecosystem.

  6. Purification and Characterization of an Extracellular Proteinase from Brevibacterium linens ATCC 9174

    OpenAIRE

    Rattray, F P; Bockelmann, W; Fox, P. F.

    1995-01-01

    An extracellular serine proteinase from Brevibacterium linens ATCC 9174 was purified to homogeneity. pH and temperature optima were 8.5 and 50(deg)C, respectively. The results for the molecular mass of the proteinase were 56 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 126 kDa by gel filtration, indicating that the native enzyme exists as a dimer. Mg(sup2+) and Ca(sup2+) activated the proteinase, as did NaCl; however, Hg(sup2+), Fe(sup2+), and Zn(sup2+) caused strong i...

  7. Purification and Characterization of an Extracellular Proteinase from Brevibacterium-Linens ATCC-9174

    DEFF Research Database (Denmark)

    Rattray, F P; Bockelmann, W; Fox, P F

    1995-01-01

    An extracellular serine proteinase from Brevibacterium linens ATCC 9174 was purified to homogeneity. pH and temperature optima were 8,5 and 50 degrees C, respectively. The results for the molecular mass of the proteinase were 56 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis...... and 126 kDa by gel filtration, indicating that the native enzyme exists as a dimer. Mg2+ and Ca2+ activated the proteinase, as did NaCl; however, Hg2+ Fe2+, and Zn2+ caused strong inhibition. The sequence of the first 20 N-terminal amino acids was NH2-Ala-Lys- Asn...

  8. Identification and Functional Analysis of the Gene Encoding Methionine-γ-Lyase in Brevibacterium linens

    OpenAIRE

    Amarita, Felix; Yvon, Mireille; Nardi, Michele; Chambellon, Emilie; Delettre, Jerôme; Bonnarme, Pascal

    2004-01-01

    The enzymatic degradation of l-methionine and subsequent formation of volatile sulfur compounds (VSCs) is believed to be essential for flavor development in cheese. l-Methionine-γ-lyase (MGL) can convert l-methionine to methanethiol (MTL), α-ketobutyrate, and ammonia. The mgl gene encoding MGL was cloned from the type strain Brevibacterium linens ATCC 9175 known to produce copious amounts of MTL and related VSCs. The disruption of the mgl gene, achieved in strain ATCC 9175, resulted in a 62% ...

  9. Purification and Characterization of l-Methionine γ-Lyase from Brevibacterium linens BL2†

    OpenAIRE

    Dias, Benjamin; Weimer, Bart

    1998-01-01

    l-Methionine γ-lyase (EC 4.4.1.11) was purified to homogeneity from Brevibacterium linens BL2, a coryneform bacterium which has been used successfully as an adjunct bacterium to improve the flavor of Cheddar cheese. The enzyme catalyzes the α,γ elimination of methionine to produce methanethiol, α-ketobutyrate, and ammonia. It is a pyridoxal phosphate-dependent enzyme, with a native molecular mass of approximately 170 kDa, consisting of four identical subunits of 43 kDa each. The purified enzy...

  10. Nucleotide sequence and taxonomical distribution of the bacteriocin gene lin cloned from Brevibacterium linens M18.

    OpenAIRE

    Valdes-Stauber, N; Scherer, S

    1996-01-01

    Linocin M18 is an antilisterial bacteriocin produced by the red smear cheese bacterium Brevibacterium linens M18. Oligonucleotide probes based on the N-terminal amino acid sequence were used to locate its single copy gene, lin, on the chromosomal DNA. The amino acid composition, N-terminal sequence, and molecular mass derived from the nucleotide sequence of an open reading frame of 798 nucleotides coding for 266 amino acids found on a 3-kb BamHI restriction fragment correspond closely to thos...

  11. China Linen Signs Agreement to Ship Fabric to Italy

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ China Linen Textile Industry,Ltd.a China-based company engaged in the production and sale of linen yarn and various types of linen fabric,announced that its wholly-owned subsidiary,Heilongjiang Lanxi Sunrise Linen Textile Industry Co.Ltd.,has signed a contract with an ltalian company to deliver approximately 1.4 million meters of semi-bleached linen fabric.The contract is valued at approximately $3.05 million.The first shipment will occur in December 2009 and continue through five total shipments to be completed in May 2010.

  12. Heterologous production of methionine-γ-lyase from brevibacterium linens in lactococcus lactis and formation of volatile sulfur compounds

    OpenAIRE

    Hanniffy, Sean; Philo, Mark; Peláez, Carmen; Gasson, M. J.; Requena, Teresa; Martínez-Cuesta, M. Carmen

    2009-01-01

    The conversion of methionine to volatile sulfur compounds (VSCs) is of great importance in flavor formation during cheese ripening and is the focus of biotechnological approaches toward flavor improvement. A synthetic mgl gene encoding methionine-γ-lyase (MGL) from Brevibacterium linens BL2 was cloned into a Lactococcus lactis expression plasmid under the control of the nisin-inducible promoter PnisA. When expressed in L. lactis and purified as a recombinant protein, MGL was shown to degrade ...

  13. Influence of Oxygen and pH on Methanethiol Production from l-Methionine by Brevibacterium linens CNRZ 918

    OpenAIRE

    Ferchichi, Mohamed; Hemme, Denis; Bouillanne, Christian

    1986-01-01

    The effects of dissolved oxygen concentration and pH on the growth of Brevibacterium linens CNRZ 918 and its production of methanethiol from l-methionine were investigated. Optimal specific methanethiol production was obtained at 25% saturation of dissolved oxygen and at a pH between 8 and 9, whereas optimal cell growth occurred at 50% oxygen saturation and when the pH was maintained constantly at 7. Methanethiol production by nonproliferating bacteria required the presence of l-methionine (7...

  14. 麻天然材料包装须有符合食品外包装的国标依据设计及应用前景%Design and Application of Linen in Food Package

    Institute of Scientific and Technical Information of China (English)

    彭建祥

    2014-01-01

    麻天然材料包装的推广应用是中国实现绿色包装的有效途径之一,在食品包装中使用麻天然材料环保又安全卫生.该文对我国麻的特性,麻包装的特点进行了梳理,阐述了麻包装应用现况,着重分析了麻在现代包装应用的新形式.图6,参3.%The widespread application of linen to package is one of the most effective ways to achieve green package in China. It is environment friendly,safe and healthy to use linen in food package. This paper,which analyzes the characteristics of linen and linen package,explores the current application of linen package. It mainly studies the new applied forms of linen package. 6figs. ,3refs.

  15. Draft Genome Sequence of Brevibacterium linens AE038-8, an Extremely Arsenic-Resistant Bacterium.

    Science.gov (United States)

    Maizel, Daniela; Utturkar, Sagar M; Brown, Steven D; Ferrero, Marcela A; Rosen, Barry P

    2015-01-01

    To understand the arsenic biogeocycles in the groundwaters at Tucumán, Argentina, we isolated Brevibacterium linens sp. strain AE38-8, obtained from arsenic-contaminated well water. This strain is extremely resistant to arsenicals and has arsenic resistance (ars) genes in its genome. Here, we report the draft genome sequence of B. linens AE38-8. PMID:25883298

  16. Draft Genome Sequence of Brevibacterium linens AE038-8, an Extremely Arsenic-Resistant Bacterium

    OpenAIRE

    Maizel, Daniela; Utturkar, Sagar M.; Brown, Steven D.; Ferrero, Marcela A.; ROSEN, BARRY P.

    2015-01-01

    To understand the arsenic biogeocycles in the groundwaters at Tucumán, Argentina, we isolated Brevibacterium linens sp. strain AE38-8, obtained from arsenic-contaminated well water. This strain is extremely resistant to arsenicals and has arsenic resistance (ars) genes in its genome. Here, we report the draft genome sequence of B. linens AE38-8.

  17. Linen Fire as Biosorbent to Remove Heavy Metal Ions From Wastewater Modeling

    Directory of Open Access Journals (Sweden)

    Ildar G. Shaikhiev

    2014-03-01

    Full Text Available The possibility of using linen fires – lnopererabotk i waste as a sorption material for the extraction of heavy metal ions from wastewater modeling. It is shown that treatment with acid solutions linen fires a low concentration increases the surface area of linen fires and thus sorption capacity for heavy metal ions. The values of the maximum sorption capacity ions Fe (III, Co (II, Ni (II and Zn (II under static and dynamic conditions. IR spectroscopy shows that along with the physical sorption process proceeds chemisorption.

  18. Bed rest and immunity

    Science.gov (United States)

    Sonnenfeld, Gerald; Aviles, Hernan; Butel, Janet S.; Shearer, William T.; Niesel, David; Pandya, Utpal; Allen, Christopher; Ochs, Hans D.; Blancher, Antoine; Abbal, Michel

    2007-02-01

    Space flight has been shown to result in altered immune responses. The current study was designed to investigate this possibility by using the bed rest model of some space flight conditions. A large number of women are included as subjects in the study. The hypothesis being tested is: 60 days head-down tilt bed rest of humans will affect the immune system and resistance to infection. Blood, urine and saliva samples will be obtained from bed rest subjects prior to, at intervals during, and after completion of 60 days of head-down tilt bed rest. Leukocyte blastogenesis, cytokine production and virus reactivation will be assessed. The ability of the subjects to respond appropriately to immunization with the neoantigen bacteriophage φX-174 will also be determined. Bed rest is being carried out at MEDES, Toulouse France, and the University of Texas Medical Branch, Galveston, TX. The studies to be carried out in France will also allow assessment of the effects of muscle/bone exercise and nutritional countermeasures on the immune system in addition to the effects of bed rest.

  19. Physicochemical characterization of thermally aged Egyptian linen dyed with organic natural dyestuffs

    Science.gov (United States)

    Kourkoumelis, N.; El-Gaoudy, H.; Varella, E.; Kovala-Demertzi, D.

    2013-08-01

    A number of organic natural dyestuffs used in dyeing in ancient times, i.e. indigo, madder, turmeric, henna, cochineal, saffron and safflower, have been used to colour Egyptian fabrics based on linen. Their physicochemical properties have been evaluated on thermally aged linen samples. The aged dyed linen samples were thoroughly examined by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and tensile strength and elongation measurements. It was found that, in the molecular level, dyes interact mainly with the cellulose compounds of the aged linen while in the macroscopic level tensile and elongation parameters are altered. Tensile strength is positively related to the dye treatment while elongation depends specifically on the type of the dye used. Results converge that the dyed textiles did indeed play a role as protecting agents affecting strength and reducing thermal deterioration.

  20. Inhibition of Brevibacterium linens by Probiotics from Dairy Products

    OpenAIRE

    Knox, Alison M.; Viljoen, Bennie C.; Lourens-Hattingh, Analie

    2005-01-01

    Brevibacterium linens is an important species in dairy products rendering a specific taste and aroma to numerous smear ripened and blue veined cheeses due to proteolysis. However, the presence of the species in South African blue veined cheeses is undesirable and consumers demand the product void of the species. Accordingly, numerous methods including microbial inhibition using fungi and bacterial probiotic cultures with possible inhibitory effects were applied in an attempt to inhibit the sp...

  1. Genotypic and technological diversity of Brevibacterium linens strains for use as adjunct starter cultures in 'Pecorino di Filiano' cheese ripened in two different environments.

    Science.gov (United States)

    Bonomo, Maria Grazia; Cafaro, Caterina; Salzano, Giovanni

    2015-01-01

    Twenty-two Brevibacterium linens strains isolated from 'Pecorino di Filiano' cheese ripened in two different environments (natural cave and storeroom) were characterized and differentiated for features of technological interest and by genotypic methods, in order to select strains with specific features to be used as surface starter cultures. Results showed significant differences among strains on the basis of physiological and technological features, indicating heterogeneity within the species. A middle-low level of proteolytic activity was observed in 27.3 % of strains, while a small group (9.1 %) showed a high ability. Lipolytic activity was observed at three different temperatures and the highest value was detected at 20 °C with 13.6 % of strains, while an increase in temperature produced a slightly lower lipolysis in all strains. The evaluation of diacetyl production revealed that only 22.8 % of strains showed this ability, and most of them were isolated from product ripened in the natural cave. All strains exhibited only leu-aminopeptidase activity, with values more elevated in strains coming from the natural cave product. The combined analysis of genotypic results with the data obtained by the features of technological interest study established that the random amplified polymorphic DNA (RAPD) clusters obtained were composed not only of different genotypes but of different profiles based on technological properties too. This study demonstrated the importance of the ripening environment that affects the typical features of the artisanal product, leading to the selection of a specific surface microflora. Characterized strains could be associated within surface starters to standardize the production process of cheese, but preserving its typical organoleptic and sensory characteristics and improving the quality of the final product. PMID:25147054

  2. 荣昌手工夏布织造工具文化空间及其设计伦理价值研究%Research cultural space and design ethic value of weaving tools in Rongchang manual linen

    Institute of Scientific and Technical Information of China (English)

    张国云; 李薇

    2015-01-01

    工具是人类在长期生产实践过程中形成的用来加工制造产品的器具。重庆荣昌手工夏布技艺工序复杂,祖祖辈辈相传,从种麻、打麻、织麻等过程都形成了相应的工具,并构成自己独特的系统。在这个系统中,人们创造出各个环节所需的手工工具,运用工具来不断精进自己的技艺,促进手工夏布生产的文化空间的生成,这种文化空间对其发展与保护有着重要的意义。本文对荣昌手工夏布的工具形成的实用价值、审美价值和伦理价值进行分析,从对手工夏布工具的构成、原料的生产、织工使用工具形成的精湛的技艺等共同体的维护中寻求其文化空间价值的保护与发展。%The tool is one kind of object which is forms in the long time practice process by the humanity, and it is the extension of hand, and also is the heart of object. Rongchang manual linen is genetic from their ancestors. It has complex process of technology and many hand-tools that can plant ramies ,cut ramie plant and weave linen, and constitute a unique system for myself. In this system, people have created hand tools that is used each link, continued to improve their skils, promoting the generation of the cultural space of hand-made cloth. This space is a signiifcant effect about the development and protection of Rongchang linen. In the text ,the author analysis the value of practical value, aesthetic value and ethics of the tool about Rongchang manual linen formation, and seek the protection and development of the cul-tural space value from the maintenance of manual tools, raw material production, weavers in the art community.

  3. Transport of aromatic amino acids by Brevibacterium linens.

    OpenAIRE

    Boyaval, P; Moreira, E; Desmazeaud, M. J.

    1983-01-01

    Whole metabolizing Brevibacterium linens cells were used to study the transport of aromatic amino acids. Kinetic results followed the Michaelis-Menten equation with apparent Km values for phenylalanine, tyrosine, and tryptophan of 24, 3.5, and 1.8 microM. Transport of these amino acids was optimum at pH 7.5 and 25 degrees C for phenylalanine and pH 8.0 and 35 degrees C for tyrosine and tryptophan. Crossed inhibitions were all noncompetitive. The only marked stereospecificity was for the L for...

  4. An MRP system for surgical linen management at a large hospital.

    Science.gov (United States)

    O'Neill, L; Murphy, M; Gray, D; Stoner, T

    2001-02-01

    Materials Requirements Planning (MRP) has been used extensively in manufacturing and other industries to improve on-time delivery and to reduce costs. In this paper, we illustrate how an MRP-type system was developed to monitor surgical linen at a large teaching hospital. We also describe a bar-code scanning 'tag and recapture' study to estimate total inventory. The hospital implemented several changes based upon our recommendations that resulted in time savings and a smoother flow of materials throughout the surgical linen supply chain. PMID:11288482

  5. An investigation into membrane bound redox carriers involved in energy transduction mechanism in Brevibacterium linens DSM 20158 with unsequenced genome.

    Science.gov (United States)

    Shabbiri, Khadija; Botting, Catherine H; Adnan, Ahmad; Fuszard, Matthew; Naseem, Shahid; Ahmed, Safeer; Shujaat, Shahida; Syed, Quratulain; Ahmad, Waqar

    2014-04-01

    Brevibacterium linens (B. linens) DSM 20158 with an unsequenced genome can be used as a non-pathogenic model to study features it has in common with other unsequenced pathogens of the same genus on the basis of comparative proteome analysis. The most efficient way to kill a pathogen is to target its energy transduction mechanism. In the present study, we have identified the redox protein complexes involved in the electron transport chain of B. linens DSM 20158 from their clear homology with the shot-gun genome sequenced strain BL2 of B. linens by using the SDS-Polyacrylamide gel electrophoresis coupled with nano LC-MS/MS mass spectrometry. B. linens is found to have a branched electron transport chain (Respiratory chain), in which electrons can enter the respiratory chain either at NADH (Complex I) or at Complex II level or at the cytochrome level. Moreover, we are able to isolate, purify, and characterize the membrane bound Complex II (succinate dehydrogenase), Complex III (menaquinone cytochrome c reductase cytochrome c subunit, Complex IV (cytochrome c oxidase), and Complex V (ATP synthase) of B. linens strain DSM 20158. PMID:24573306

  6. Sea bed mapping and inspection

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The conference has 24 presentations on the topics: Sea bed mapping, inspection, positioning, hydrography, marine archaeology, remote operation vehicles and computerized simulation technologies, oil field activities and plans, technological experiences and problems. (tk)

  7. Linen, Silver, Slaves, and Coffee: A Spatial Approach to Central Europe’s Entanglements with the Atlantic Economy

    Directory of Open Access Journals (Sweden)

    Weber, Klaus

    2015-12-01

    Full Text Available In German scholarship of the post-war period, the category of space was regarded as discredited, because of its abuse during the Nazi period. This applies in particular to the 1970s and 80s, when novel approaches in social and economic history were developed. Research on proto-industrialisation, broadly examining its internal structures, did not take into account the export orientation of Central Europe’s early modern commodity production. At the same time, the expanding research on Europe’s Atlantic empires, including the trans-Atlantic slave trade, did hardly take notice of the manufactures from the Holy Roman Empire, distributed all around the Atlantic basin. This paper examines those conditions favouring German proto-industries which are relevant for a ‘spatial approach’ to the phenomenon. It also covers the late medieval beginnings of this process, in order to demonstrate the continuity of Central Europe’s entanglement with the Atlantic world. The paper further emphasises that any future research using spatial categories must be aware of the ideological contamination of the German term ‘Raum’ during the 19th and 20th century. The interlace of economic and social history with historiography demands a compilation from current and older research literature, some of it on different regions and subjectsEn la escuela alemana del período de pos-guerra la categoría de espacio fue desprestigiada debido a los abusos sucedidos durante el período nazi. Esto se aplica en especial a los años de 1970 y 1980, cuando se desarrollaron los nuevos enfoques en historia social y económica. Las investigaciones sobre la proto-industrialización en Europa Central durante la Edad Moderna que examinan, en líneas generales, sus estructuras internas, no tuvieron en cuenta la dimensión espacial de las exportaciones de su producción. Al mismo tiempo, las crecientes investigaciones de los imperios europeos en el Atlántico, incluso del comercio de

  8. Corkscrew Yarns and Chemical Fiber Linen Imitations%碧绉线型与化纤仿麻织物

    Institute of Scientific and Technical Information of China (English)

    李旦

    2001-01-01

    On the basis of analyzing corkscrew-yarn-typed chemical fiberlinen imitations, investigations are made on how to grab market trends and determine design ideas in the development of new products.%通过对碧绉线型的化纤仿麻系列产品的解析,探讨在新产品设计中,怎样把握市场流行动态,确定新产品的设计思路,以期对企业开发新产品有所帮助。

  9. 棉麻纤维液氨改性成套装备上下物料系统设计%Design of Material Loading and Unloading System for Liquid Ammonia Treatment Equipment of Cotton and Linen Fiber

    Institute of Scientific and Technical Information of China (English)

    张凯

    2012-01-01

    摘要:目前棉麻纤维液氨改性系统的上下料采用人工方式进行,存在工作效率低、工人劳动强度大的缺点,基于发明问题解决理论(TRIZ)对液氨改性成套装备物料输送系统进行了创新设计,采用对心曲柄齿轮齿条机构和电磁铁来实现物料箱在小空间长行程的上下料,采用欧姆龙公司的CPlL型PLC来实现整个系统的控制,可实现棉麻纤维液氨改性成套装备物料包装输送系统的自动化。%The currently using material loading and unloading system for liquid ammonia treatment equipment of cot- ton and linen fiber has shortcomings of low efficiency and high labor intensity. In order to get rid of these shortcomings and based on TRIZ theory, the innovative design of complete material delivery system for liquid ammonia treatment e- quipment was made. The design realized material loading and unloading in small space and long distance by using heart crank gear rack mechanism and solenoids. Type CP1 L PLC from Omron was used to control of the entire system, to realize automation of material delivery system for liquid ammonia treatment equipment of cotton and linen fiber.

  10. 太行鸡与矮脚麻鸡蛋品质比较研究%Comparative Study between Taihang Chicken and Short-leg-linen Chicken's Egg Quality

    Institute of Scientific and Technical Information of China (English)

    王学静; 魏忠华; 杨树玲; 李祥龙; 李杰峰

    2012-01-01

      Random taking 100 eggs of the 214 day-old introducing breed (Short-leg-linen chichen) and local breed (Taihang chichen) to determine the egg's weight, egg-shaped index, specific gravity, yolk colour, Haugh u-nit , yolk ratio, eggshell thickness, shell strength, flesh and blood spot ratio. The results show that the two breeds' egg quality without significant difference (P>0.05) about the weight , specific gravity, yolk colour, shell thick-ness;But the Haugh unit and the egg yolk rate are very significant difference (P0.05);哈氏单位、蛋黄比率差异极显著(P<0.01);蛋形指数、蛋壳强度差异显著(P<0.05).

  11. THE BAUXITES AND JELAR - BEDS

    Directory of Open Access Journals (Sweden)

    Krešimir Sakač

    1993-12-01

    Full Text Available Minor bauxite deposits and occurrences were formed in technically disturbed environments in the middle part of the Adriatic geotectonic unit in Dinarides, contemporary with the clastic Jelar-beds in the Late Lutetian time. Uneven chemical composition of these Eocene bauxites, their sporadic occurrences in developed paleorelief as well as characteristic petrographic composition of the immediate overlying rocks point out at different genetical conditions (the paper is published in Croatian.

  12. Method and apparatus for a combination moving bed thermal treatment reactor and moving bed filter

    Energy Technology Data Exchange (ETDEWEB)

    Badger, Phillip C.; Dunn, Jr., Kenneth J.

    2015-09-01

    A moving bed gasification/thermal treatment reactor includes a geometry in which moving bed reactor particles serve as both a moving bed filter and a heat carrier to provide thermal energy for thermal treatment reactions, such that the moving bed filter and the heat carrier are one and the same to remove solid particulates or droplets generated by thermal treatment processes or injected into the moving bed filter from other sources.

  13. Medium optimization of protease production by Brevibacterium linens DSM 20158, using statistical approach

    OpenAIRE

    Khadija Shabbiri; Ahmad Adnan; Sania Jamil; Waqar Ahmad; Bushra Noor; H.M. Rafique

    2012-01-01

    Various cultivation parameters were optimized for the production of extra cellular protease by Brevibacterium linens DSM 20158 grown in solid state fermentation conditions using statistical approach. The cultivation variables were screened by the Plackett-Burman design and four significant variables (soybean meal, wheat bran, (NH4)2SO4 and inoculum size were further optimized via central composite design (CCD) using a response surface methodological approach. Using the optimal factors (soybea...

  14. Medium optimization of protease production by Brevibacterium linens DSM 20158, using statistical approach

    OpenAIRE

    Shabbiri, Khadija; Adnan, Ahmad; Jamil, Sania; Ahmad, Waqar; Noor, Bushra; H.M. Rafique

    2012-01-01

    Various cultivation parameters were optimized for the production of extra cellular protease by Brevibacterium linens DSM 20158 grown in solid state fermentation conditions using statistical approach. The cultivation variables were screened by the Plackett–Burman design and four significant variables (soybean meal, wheat bran, (NH4)2SO4 and inoculum size were further optimized via central composite design (CCD) using a response surface methodological approach. Using the optimal factors (soybea...

  15. Container and Raised-Bed Gardening

    OpenAIRE

    Niemiera, Alexander Xavier, 1951-

    2009-01-01

    Raised beds, while requiring a high initial labor input, offer improved growing conditions and advantages compared to the existing soil. Improved plant growth, increased yields, and better accessibility are reasons to construct raised beds. This publication reviews the proper containers and plants, planting instructions, watering and potting soils, overwintering plants and more.

  16. Incipient motion of gravel and coal beds

    Indian Academy of Sciences (India)

    Subhasish Dey; Uddaraju V Raju

    2002-10-01

    An experimental study on incipient motion of gravel and coal beds under unidirectional steady-uniform flow is presented. Experiments were carried out in a flume with various sizes of gravel and coal samples. The critical bed shear stresses for the experimental runs determined using side-wall correction show considerable disagreement with the standard curves. The characteristic parameters affecting the incipient motion of particles in rough-turbulent regime, identified based on physical reasoning and dimensional analysis, are the Shields parameter, particle Froude number, non-dimensional particle diameter and non-dimensional flow depth. Equations of critical bed shear stress for the initial movement of gravel and coal beds were obtained using experimental data. The method of application of critical bed shear stress equations is also mentioned.

  17. Prevalence, Knowledge, and Concern About Bed Bugs.

    Science.gov (United States)

    Kaylor, Mary Beth; Wenning, Paul; Eddy, Christopher

    2015-01-01

    Recent research suggests that the resurgence of bed bugs in the U.S. has occurred at an alarming rate. Assumptions have been made that socioeconomic status is not associated with the prevalence of bed bug infestations. Little information is available at the local level, however, about the prevalence of bed bugs in private homes. The authors' pilot study aimed to identify prevalence, knowledge, and concern about bed bugs in one higher income village in Ohio utilizing survey methodology. Responses from 96 individuals who completed the Prevalence, Knowledge, and Concern About Bed Bugs survey were utilized for analysis. The majority of the sample respondents were white and 95% reported that they owned their residence. Only 6% knew someone with bed bugs. Additionally, 52% reported they were somewhat concerned about bed bugs. About 46% reported that they had changed their behavior. For a higher income area, the prevalence was dissimilar to the rate reported in the general public (about 20%). This suggests that bed bugs may be an environmental issue effecting low-income populations disproportionately. Further research is needed in areas of differing socioeconomic levels. PMID:26427264

  18. Karg, S. New projects within the FLAX Network. In: Karg S. (ed.) Flax (Linum usitatissimum L.) - a natural resource for food and textiles for 8000 years. Cross-disciplinary investigations on the evolution and cultural history of flax and linen. Programme and abstracts of the second, workshop 28-30 June 2010 at Sonnerupgaard and in the Land of Legends, Denmark. Communicating Culture. Workshop Info 2, 2010, 4-6

    DEFF Research Database (Denmark)

    Karg, Sabine

    2010-01-01

    Karg, S. New projects within the FLAX Network. In: Karg S. (ed.) Flax (Linum usitatissimum L.) - a natural resource for food and textiles for 8000 years. Cross-disciplinary investigations on the evolution and cultural history of flax and linen. Programme and abstracts of the second workshop 28......-30 June 2010 at Sonnerupgaard and in the Land of Legends, Denmark. Communicating Culture. Workshop Info 2, 2010, 4-6...

  19. Determination of true bed thickness using folded bed model and borehole data

    Energy Technology Data Exchange (ETDEWEB)

    Xu, S.S.; Velasquillo-Martinez, L.G.; Grajales-Nishimura, J.M.; Murillo-Muneton, G. [Inst. Mexicano del Petroleo, Mexico City (Mexico); Garcia-Hernandez, J. [Petroleos Mexicanos Exploracion y Produccion, Tamaulipas (Mexico); Nieto-Samaniego, A.F. [Nacional Autonoma de Mexico Univ., Veracruz (Mexico). Centro de Geociencias

    2007-11-15

    The actual thickness of a given formation perpendicular to the bedding plane is known as the true bed thickness. Petroleum engineers rely on information regarding true bed thickness, particularly in dipping beds and in deviated holes because reservoir volume and isochore maps depend on these properties and not on the measured thickness. True bed thickness can be estimated from information gathered from well logs such as the dipmeter and borehole images. However, when deviations and dips exceed 10 degrees, corrections are needed. In this paper, a folded bed model was proposed to calculate the true bed thickness in the subsurface utilizing well log data. The value of true bed thickness (t) was shown to depend on the angle and the direction of the dip of the measured formation, as well as the drift angle and azimuth of the borehole. A case study from the Cantarell oil field in the southern Gulf of Mexico, offshore Campeche, was used to test the folded bed method. The model was shown to yield more uniform spatial change of the values of t, compared to the monoclinal bed model that often overestimates the average value of t. The maximum relative deviation of t from the monoclinal bed model reached 22.3 per cent and the maximum absolute deviation of t reached 34.5 m. The key factors that influence the values of t were found to be the bed dip, the dip difference between the top and base of the bed and the deviated angle of the well. The folded bed model yielded fewer changed values of the true bed thickness. 10 refs., 2 tabs., 9 figs.

  20. Heat and Mass Transfer Enforcement of Vibrating Fluidized Bed

    Institute of Scientific and Technical Information of China (English)

    ChuZhide; YangJunhong; 等

    1994-01-01

    This paper briefly introduces the development of vibrating fluidized bed at home and abroad,elaborates the vibration properties of vibrating fluidized bed.the fluidizing velocity and pressure drop of the bed layer,it also deduces the non-steady state drying dynamic equations of vibrating fluidized bed,analyzes main factors which influence the drying rate and inquires into drying rules of fixed bed and vibrating fluidized bed.

  1. 稀土在亚麻织物活性染料染色中的应用%Application of Rare Earth in Dyeing of Reactive Dyes of Linen Fabric

    Institute of Scientific and Technical Information of China (English)

    张绍萍

    2012-01-01

    This paper aims at explore the principle of accelerating in rare earth in dyeing of reactive dyes of linen fabric,and introduces the dyeing of linen fabric with reactive dyes of rare earth accelerating agent.%探究稀土在亚麻织物活性染料染色中的促染原理,介绍亚麻织物稀土促染活性染料的染色工艺。

  2. Cognitive and emotional functioning in BED

    OpenAIRE

    Kittel, Rebekka; Brauhardt, Anne; Hilbert, Anja

    2016-01-01

    Objective: Binge-eating disorder (BED) is characterized by recurrent episodes of binge eating and is associated with eating disorder and general psychopathology and overweight/obesity. Deficits in cognitive and emotional functioning for eating disorders or obesity have been reported. However, a systematic review on cognitive and emotional functioning for individuals with BED is lacking. Method: A systematic literature search was conducted across three databases (Medline, PubMed, and PsycI...

  3. Peering inside the granular bed: illuminating feedbacks between bed-load transport and bed-structure evolution

    Science.gov (United States)

    Houssais, M.; Jerolmack, D. J.; Martin, R. L.

    2013-12-01

    The threshold of motion is perhaps the most important quantity to determine for understanding rates of bed load transport, however it is a moving target. Decades of research show that it changes in space and in time within a river, and is highly variable among different systems; however, these differences are not mechanistically understood. Recent researchers have proposed that the critical Shields stress is strongly dependent on the local configuration of the sediment bed [Frey and Church, 2011]. Critical Shields stress has been observed to change following sediment-transporting flood events in natural rivers [e.g., Turowski et al., 2011], while small-scale laboratory experiments have produced declining bed load transport rates associated with slow bed compaction [Charru et al., 2004]. However, no direct measurements have been made of the evolving bed structure under bed load transport, so the connection between granular controls and the threshold of motion remains uncertain. A perspective we adopt is that granular effects determine the critical Shields stress, while the fluid supplies a distribution of driving stresses. In order to isolate the granular effect, we undertake laminar bed load transport experiments using plastic beads sheared by a viscous oil in a small, annular flume. The fluid and beads are refractive index matched, and the fluid impregnated with a fluorescing powder. When illuminated with a planar laser sheet, we are able to image slices of the granular bed while also tracking the overlying sediment transport. We present the first results showing how bed load transport influences granular packing, and how changes in packing influence the threshold of motion to feed back on bed load transport rates. This effect may account for much of the variability observed in the threshold of motion in natural streams, and by extension offers a plausible explanation for hysteresis in bed load transport rates observed during floods. Charru, F., H. Mouilleron, and

  4. Specificity of an extracellular proteinase from Brevibacterium linens ATCC 9174 on bovine alpha s1-casein.

    OpenAIRE

    Rattray, F P; Fox, P. F.; Healy, A.

    1996-01-01

    The specificity of the extracellular proteinase from Brevibacterium linens ATCC 9174 on bovine alpha s1-casein was studied. Hydrolysis was monitored over time by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (PAGE) and urea-PAGE. The major pH 4.6-soluble peptides were isolated by high-performance liquid chromatography and identified by N-terminal amino acid sequencing and mass spectrometry. The time course of peptide formation indicated that His-8-Gln-9, Ser-161-Gly-162, and eithe...

  5. Specificity of an extracellular proteinase from Brevibacterium linens ATCC 9174 on bovine beta-casein.

    OpenAIRE

    Rattray, F P; Fox, P. F.; Healy, A.

    1997-01-01

    The specificity of the extracellular proteinase from Brevibacterium linens ATCC 9174 on bovine beta-casein was studied. Hydrolysis was monitored over time by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (PAGE) and urea-PAGE. The major pH 4.6-soluble peptides were isolated by high-performance liquid chromatography and identified by N-terminal amino acid sequencing and mass spectrometry. The major sites of hydrolysis were Ser-18-Ser-19, Glu-20-Glu-21, Gln-56-Ser-57, Gln-72-Asn-73, ...

  6. Bed and breakfasts in Virginia :identification and success factors

    OpenAIRE

    Kaufman, Tammie J

    1994-01-01

    Virginia bed and breakfast operations were researched in order to determine the attitudes/beliefs which were necessary for success in the bed and breakfast industry. The objectives of the study were to: (1) identify demographics of Virginia bed and breakfast operations; (2) identify successful bed and breakfast operations based upon their self definition of success; (3) identify the attitudes and beliefs operators believe are necessary for success in running a bed and breakf...

  7. Bed Bug Infestations and Control Practices in China: Implications for Fighting the Global Bed Bug Resurgence

    Directory of Open Access Journals (Sweden)

    Changlu Wang

    2011-04-01

    Full Text Available The bed bug resurgence in North America, Europe, and Australia has elicited interest in investigating the causes of the widespread and increasing infestations and in developing more effective control strategies. In order to extend global perspectives on bed bug management, we reviewed bed bug literature in China by searching five Chinese language electronic databases. We also conducted telephone interviews of 68 pest control firms in two cities during March 2011. In addition, we conducted telephone interviews to 68 pest control companies within two cities in March 2011. Two species of bed bugs (Cimex lectularius L. and Cimex hemipterus (F. are known to occur in China. These were common urban pests before the early1980s. Nationwide “Four-Pest Elimination” campaigns (bed bugs being one of the targeted pests were implemented in China from 1960 to the early 1980s. These campaigns succeeded in the elimination of bed bug infestations in most communities. Commonly used bed bug control methods included applications of hot water, sealing of bed bug harborages, physical removal, and applications of residual insecticides (mainly organophosphate sprays or dusts. Although international and domestic travel has increased rapidly in China over the past decade (2000–2010, there have only been sporadic new infestations reported in recent years. During 1999–2009, all documented bed bug infestations were found in group living facilities (military dormitories, worker dormitories, and prisons, hotels, or trains. One city (Shenzhen city near Hong Kong experienced significantly higher number of bed bug infestations. This city is characterized by a high concentration of migratory factory workers. Current bed bug control practices include educating residents, washing, reducing clutter, putting items under the hot sun in summer, and applying insecticides (pyrethroids or organophosphates. There have not been any studies or reports on bed bug insecticide

  8. Bed Bug Infestations and Control Practices in China: Implications for Fighting the Global Bed Bug Resurgence

    OpenAIRE

    Changlu Wang; Xiujun Wen

    2011-01-01

    The bed bug resurgence in North America, Europe, and Australia has elicited interest in investigating the causes of the widespread and increasing infestations and in developing more effective control strategies. In order to extend global perspectives on bed bug management, we reviewed bed bug literature in China by searching five Chinese language electronic databases. We conducted telephone interviews of staff from 77 Health and Epidemic Prevention Stations in six Chinese cities in November 2...

  9. WTP Pretreatment Facility Potential Design Deficiencies--Sliding Bed and Sliding Bed Erosion Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, E. K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-05-06

    This assessment is based on readily available literature and discusses both Newtonian and non-Newtonian slurries with respect to sliding beds and erosion due to sliding beds. This report does not quantify the size of the sliding beds or erosion rates due to sliding beds, but only assesses if they could be present. This assessment addresses process pipelines in the Pretreatment (PT) facility and the high level waste (HLW) transfer lines leaving the PT facility to the HLW vitrification facility concentrate receipt vessel.

  10. Cardiac atrophy after bed rest and spaceflight

    Science.gov (United States)

    Perhonen, M. A.; Franco, F.; Lane, L. D.; Buckey, J. C.; Blomqvist, C. G.; Zerwekh, J. E.; Peshock, R. M.; Weatherall, P. T.; Levine, B. D.

    2001-01-01

    Cardiac muscle adapts well to changes in loading conditions. For example, left ventricular (LV) hypertrophy may be induced physiologically (via exercise training) or pathologically (via hypertension or valvular heart disease). If hypertension is treated, LV hypertrophy regresses, suggesting a sensitivity to LV work. However, whether physical inactivity in nonathletic populations causes adaptive changes in LV mass or even frank atrophy is not clear. We exposed previously sedentary men to 6 (n = 5) and 12 (n = 3) wk of horizontal bed rest. LV and right ventricular (RV) mass and end-diastolic volume were measured using cine magnetic resonance imaging (MRI) at 2, 6, and 12 wk of bed rest; five healthy men were also studied before and after at least 6 wk of routine daily activities as controls. In addition, four astronauts were exposed to the complete elimination of hydrostatic gradients during a spaceflight of 10 days. During bed rest, LV mass decreased by 8.0 +/- 2.2% (P = 0.005) after 6 wk with an additional atrophy of 7.6 +/- 2.3% in the subjects who remained in bed for 12 wk; there was no change in LV mass for the control subjects (153.0 +/- 12.2 vs. 153.4 +/- 12.1 g, P = 0.81). Mean wall thickness decreased (4 +/- 2.5%, P = 0.01) after 6 wk of bed rest associated with the decrease in LV mass, suggesting a physiological remodeling with respect to altered load. LV end-diastolic volume decreased by 14 +/- 1.7% (P = 0.002) after 2 wk of bed rest and changed minimally thereafter. After 6 wk of bed rest, RV free wall mass decreased by 10 +/- 2.7% (P = 0.06) and RV end-diastolic volume by 16 +/- 7.9% (P = 0.06). After spaceflight, LV mass decreased by 12 +/- 6.9% (P = 0.07). In conclusion, cardiac atrophy occurs during prolonged (6 wk) horizontal bed rest and may also occur after short-term spaceflight. We suggest that cardiac atrophy is due to a physiological adaptation to reduced myocardial load and work in real or simulated microgravity and demonstrates the plasticity

  11. Tinjauan Tentang Pendistribusian Linen Pada Departemen Housekeeping Di Hotel Danau Toba Internasional Medan

    OpenAIRE

    Munthe, Aris Ricardo

    2011-01-01

    Hotel Danau Toba Internasional merupakan salah satu hotel berbintang lima (*****) di kota Medan. Hotel ini mempunyai departemen housekeeping yang memegang tanggungjawab penuh dalam pendistribusian linen. Proses pendistribusian linen masih ditemukan beberapa kekurangan yaitu kurang melaksanakan standar operasional prosedur, sering mengalami keterlambatan dalam tiap shiftnya, mengalami kekurangan tenaga kerja, dan kekurangan parstock dalam memenuhi kebutuhan linnen, dan kurang mengetahui cara m...

  12. Loading and Unloading Weaned Pigs: Effects of Bedding Types, Ramp Angle, and Bedding Moisture

    Directory of Open Access Journals (Sweden)

    Arlene Garcia

    2014-12-01

    Full Text Available The use of non-slip surfaces during loading and unloading of weaned pigs plays an important role in animal welfare and economics of the pork industry. Currently, the guidelines available only suggest the use of ramps below 20° to load and unload pigs. Three ramp angles (0°, 10° or 20°, five bedding materials (nothing, sand, feed, wood shavings or wheat straw hay, two moistures (dry or wet bedding; >50% moisture over two seasons (>23.9 °C summer, <23.9 °C winter were assessed for slips/falls/vocalizations (n = 6,000 pig observations. “Score” was calculated by the sum of slips, falls, and vocalizations. With the exception of using feed as a bedding, all beddings provided some protection against elevated slips, falls, and vocalizations (P < 0.01. Providing bedding reduced (P < 0.05 scores regardless of whether the bedding was dry or wet. Scores increased as the slope increased (P < 0.01. Provision of bedding, other than feed, at slopes greater than zero, decreased slips, falls and vocalizations. The total time it took to load and unload pigs was

  13. Theoretical comparison of packed bed and fluidized bed membrane reactors for methane reforming

    NARCIS (Netherlands)

    Gallucci, Fausto; Sint Annaland, van Martin; Kuipers, J.A.M.

    2010-01-01

    In this theoretical work the performance of different membrane reactor concepts, both fluidized bed and packed bed membrane reactors, has been compared for ultra-pure hydrogen production via methane reforming. Using detailed theoretical models, the required membrane area to reach a given conversion

  14. Fluidized-bed and packed-bed characteristics of gel beads

    NARCIS (Netherlands)

    Zessen, van E.; Tramper, J.; Rinzema, A.; Beeftink, H.H.

    2005-01-01

    A liquid-fluidized bed or packed bed with gel beads is attractive as an immobilized-cell bioreactor. The performance of such bioreactors is influenced by the physical behavior of these beads. Three different but related aspects involving the drag force between particles and liquid were studied for f

  15. Agglomeration in fluidized beds: detection and counteraction

    NARCIS (Netherlands)

    Bartels. M.

    2008-01-01

    Fluidized beds comprise a quantity of solid particles that is suspended by an upward flowing gas. They are used for a variety of processes in the chemical industry, such as catalytic reactions, drying, coating and energy conversion. A major problem in industrial practice is the occurrence of unwante

  16. Prevention and Control of Bed Bugs in Residences

    Science.gov (United States)

    ... on a backpack Bed bugs along a mattress seam Bed bugs on the underside of a box ... Controlling an infestation requires very detailed work, much moving and disassembly of furniture, and specialty equipment. Careful ...

  17. Circulating fluidized bed boilers design and operations

    CERN Document Server

    Basu, Prabir

    1991-01-01

    This book provides practicing engineers and students with insight into the design and operation of circulating fluidized bed (CFB) boilers. Through a combination of theoretical concepts and practical experience, this book gives the reader a basic understanding of the many aspects of this subject.Important environmental considerations, including solid waste disposal and predicted emissions, are addressed individually in separate chapters. This book places an emphasis on combustion, hydrodynamics, heat transfer, and material issues, and illustrates these concepts with numerous examples of pres

  18. Fluidized Bed Asbestos Sampler Design and Testing

    Energy Technology Data Exchange (ETDEWEB)

    Karen E. Wright; Barry H. O' Brien

    2007-12-01

    A large number of samples are required to characterize a site contaminated with asbestos from previous mine or other industrial operations. Current methods, such as EPA Region 10’s glovebox method, or the Berman Elutriator method are time consuming and costly primarily because the equipment is difficult to decontaminate between samples. EPA desires a shorter and less costly method for characterizing soil samples for asbestos. The objective of this was to design and test a qualitative asbestos sampler that operates as a fluidized bed. The proposed sampler employs a conical spouted bed to vigorously mix the soil and separate fine particulate including asbestos fibers on filters. The filters are then analyzed using transmission electron microscopy for presence of asbestos. During initial testing of a glass prototype using ASTM 20/30 sand and clay fines as asbestos surrogates, fine particulate adhered to the sides of the glass vessel and the tubing to the collection filter – presumably due to static charge on the fine particulate. This limited the fines recovery to ~5% of the amount added to the sand surrogate. A second prototype was constructed of stainless steel, which improved fines recovery to about 10%. Fines recovery was increased to 15% by either humidifying the inlet air or introducing a voltage probe in the air space above the sample. Since this was not a substantial improvement, testing using the steel prototype proceeded without using these techniques. Final testing of the second prototype using asbestos suggests that the fluidized bed is considerably more sensitive than the Berman elutriator method. Using a sand/tremolite mixture with 0.005% tremolite, the Berman elutriator did not segregate any asbestos structures while the fluidized bed segregated an average of 11.7. The fluidized bed was also able to segregate structures in samples containing asbestos at a 0.0001% concentration, while the Berman elutriator method did not detect any fibers at this

  19. Mineral resources of the Devil's Garden Lava Bed, Squaw Ridge Lava Bed, and Four Craters Lava Bed Wilderness Study Areas, Lake County, Oregon

    Energy Technology Data Exchange (ETDEWEB)

    Keith, W.J.; King, H.D.; Gettings, M.E. (Geological Survey, Reston, VA (USA)); Johnson, F.L. (US Bureau of Mines (US))

    1988-01-01

    The Devel's Garden lava Bed, Squaw Ridge Lava Bed, and Four Craters Lava Bed Wilderness Study Areas include approximately 70,940 acres and are underlain entirely by Pleistocene or Holocene lava flows and associated sediments. There is no evidence of hydrothermal alteration in the study areas. No resources were identified in the study areas, but there is low potential for perlite resources in the southern part of the Devil's Garden Lava Bed and the northern half of the Squaw Ridge Lava Bed areas. All three study areas have low potential for geothermal resources and for oil and gas resources.

  20. Comparison of packed bed and fluidized bed membrane reactors for methane reforming

    OpenAIRE

    Gallucci, Fausto; Sint Annaland, van, Martin; Kuipers, J.A.M.

    2009-01-01

    In this work the performance of different membrane reactor concepts, both fluidized bed and packed bed membrane reactors, have been compared for the reforming of methane for the production of ultra-pure hydrogen. Using detailed theoretical models, the required membrane area to reach a given conversion and the prevailing temperature profiles have been compared. The extent of mass and heat transfer limitations in the different reactors have been evaluated, and strategies to decrease (or avoid) ...

  1. Biomass ash - bed material interactions leading to agglomeration in fluidised bed combustion and gasification

    Energy Technology Data Exchange (ETDEWEB)

    Visser, H.J.M.; Hofmans, H.; Huijnen, R.; Kastelein, R.; Kiel, J.H.A. [ECN Biomass, Petten (Netherlands)

    2000-07-01

    The present study has been aimed at improving the fundamental understanding of mechanisms underlying agglomeration and defluidisation in fluidised bed combustion and gasification of biomass and waste. To this purpose dedicated lab-scale static heating and fluidisation experiments have been conducted with carefully selected and prepared ashes and bed materials, viz. straw ash/sand and willow ash/sand mixtures, mullite subjected to straw gasification and artificially coated mullite. The main conclusion is that ash/bed material interaction processes are very important and often determine the bed agglomeration and defluidisation tendency. In the static heating experiments with both ash/sand mixtures, partial melting-segregation of ash components and dissolution/reaction with the bed material are processes that determine the melt composition. This melt composition and behaviour can deviate considerably form expectations based on ash-only data. Artificially coated bed materials prove to be very useful for systematic studies on the influence of coating composition and thickness on agglomeration tendency. For the coated mullite samples, different stages in the defluidisation process are identified and the influence of coating properties (thickness, composition, morphology) and operating parameters is elucidated. The behaviour of the mullite appears to be dominated by a remnant glass phase. On the one hand, this glass phase accounts for an alkali-getter capability, while on the other hand it is mainly responsible for agglomeration at temperatures {>=} 800C. 3 refs.

  2. Fluctuations and time scales for bed-load sediment motion over a smooth bed

    Institute of Scientific and Technical Information of China (English)

    Francesco Ballio n; Alessio Radice

    2015-01-01

    Results are presented for experiments of bed-load sediment transport over a plane, smooth bed. The smooth-bed configuration, though not adequate for mimicking natural streams, enables the effects of bed roughness to be filtered out, thus, highlighting the role of flow turbulence for particle dynamics. Sediments were individually tracked along their paths, measuring position and velocity of the individual grains. A number of analyses were then applied to the data: probability density function, auto-correla-tion, and spectra of the grain velocity. Several Lagrangian time scales of particle motion were obtained and compared to available data for the turbulent flow field to determine a phenomenological inter-pretation of the process.

  3. It is time to wash the linen.

    Science.gov (United States)

    Bajaj, Rajiv

    2007-01-01

    The unethical practice of commissions in private healthcare requires an open debate since it leads to expensive and hazardous healthcare. Doctors are accused of being sales agents and law breakers, private hospitals resemble luxury hotels, the consumer has become fair game whenever he/she has money, and our profession and society are rendered insensitive to human suffering. At the root of this malaise is the unplanned promotion of healthcare as a free market product. This very complex product, which is required in times of stress and vulnerability, has been institutionalized as a business for profiteering in the absence of adequate checks and balances. The product is inherently unsuited for the free market because the consumer cannot be king unless he is empowered to choose wisely. Not enough has been done to address this deficiency. Efforts are required to strengthen non-profit health facilities; to make the consumer wise and minimize her/his exposure to doctored health information. The present unethical practices of our profession are not the fault of doctors or the Medical Council of India, and punitive measures would be inappropriate. We should start with the creation of a government health website which educates the public about modern healthcare, and by regulating advertisement of health products. Since health personnel, officials and news media are directly benefited by the present malpractices, corrective will require consumer participation. PMID:17867621

  4. Deleterious Thermal Effects Due To Randomized Flow Paths in Pebble Bed, and Particle Bed Style Reactors

    Science.gov (United States)

    Moran, Robert P.

    2013-01-01

    A review of literature associated with Pebble Bed and Particle Bed reactor core research has revealed a systemic problem inherent to reactor core concepts which utilize randomized rather than structured coolant channel flow paths. For both the Pebble Bed and Particle Bed Reactor designs; case studies reveal that for indeterminate reasons, regions within the core would suffer from excessive heating leading to thermal runaway and localized fuel melting. A thermal Computational Fluid Dynamics model was utilized to verify that In both the Pebble Bed and Particle Bed Reactor concepts randomized coolant channel pathways combined with localized high temperature regions would work together to resist the flow of coolant diverting it away from where it is needed the most to cooler less resistive pathways where it is needed the least. In other words given the choice via randomized coolant pathways the reactor coolant will take the path of least resistance, and hot zones offer the highest resistance. Having identified the relationship between randomized coolant channel pathways and localized fuel melting it is now safe to assume that other reactor concepts that utilize randomized coolant pathways such as the foam core reactor are also susceptible to this phenomenon.

  5. Medium optimization of protease production by Brevibacterium linens DSM 20158, using statistical approach

    Directory of Open Access Journals (Sweden)

    Khadija Shabbiri

    2012-09-01

    Full Text Available Various cultivation parameters were optimized for the production of extra cellular protease by Brevibacterium linens DSM 20158 grown in solid state fermentation conditions using statistical approach. The cultivation variables were screened by the Plackett-Burman design and four significant variables (soybean meal, wheat bran, (NH42SO4 and inoculum size were further optimized via central composite design (CCD using a response surface methodological approach. Using the optimal factors (soybean meal 12.0g, wheat bran 8.50g, (NH42SO4 0.45g and inoculum size 3.50%, the rate of protease production was found to be twofold higher in the optimized medium as compared to the unoptimized reference medium.

  6. Fluidized-bed reactors processes and operating conditions

    CERN Document Server

    Yates, John G

    2016-01-01

    The fluidized-bed reactor is the centerpiece of industrial fluidization processes. This book focuses on the design and operation of fluidized beds in many different industrial processes, emphasizing the rationale for choosing fluidized beds for each particular process. The book starts with a brief history of fluidization from its inception in the 1940’s. The authors present both the fluid dynamics of gas-solid fluidized beds and the extensive experimental studies of operating systems and they set them in the context of operating processes that use fluid-bed reactors. Chemical engineering students and postdocs as well as practicing engineers will find great interest in this book.

  7. Fluidized bed combustion: mixing and pollutant limitation

    Energy Technology Data Exchange (ETDEWEB)

    Leckner, B. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Energy Conversion

    1997-10-01

    Fluidized bed combustion (FBC) has been applied commercially during a few decades, and sufficient knowledge is gained to design boilers with sizes of up to several hundreds of megawatt thermal power (MW{sub th}). The knowledge of what goes on inside a large combustion chamber is still limited, however, and this impedes further optimization and efficient solution of problems that might occur. Despite this lack of knowledge the present survey deals with combustion chamber processes and discusses mixing and distribution of fuel and air in the combustion chamber and its importance for sulphur capture and reduction of emissions of nitrogen oxides. It is desirable to present the material in a general way and to cover the entire field of FBC. However, the scarce openly published information deals mostly with coal combustion in atmospheric circulating fluidized bed (CFB) combustors, and therefore this application will receive most attention, but reference is also made to pressurized combustion and to other fuels than coal. In this context the important work made in the LIEKKI project on the analysis of different fuels and on the influence of pressure should be especially pointed out. (orig.)

  8. Rock bed thermal storage: Concepts and costs

    Science.gov (United States)

    Allen, Kenneth; von Backström, Theodor; Joubert, Eugene; Gauché, Paul

    2016-05-01

    Thermal storage enables concentrating solar power (CSP) plants to provide baseload or dispatchable power. Currently CSP plants use two-tank molten salt thermal storage, with estimated capital costs of about 22-30 /kWhth. In the interests of reducing CSP costs, alternative storage concepts have been proposed. In particular, packed rock beds with air as the heat transfer fluid offer the potential of lower cost storage because of the low cost and abundance of rock. Two rock bed storage concepts which have been formulated for use at temperatures up to at least 600 °C are presented and a brief analysis and cost estimate is given. The cost estimate shows that both concepts are capable of capital costs less than 15 /kWhth at scales larger than 1000 MWhth. Depending on the design and the costs of scaling containment, capital costs as low as 5-8 /kWhth may be possible. These costs are between a half and a third of current molten salt costs.

  9. INVESTIGATION OF FUEL CHEMISTRY AND BED PERFORMANCE IN A FLUIDIZED BED BLACK LIQUOR STEAM REFORMER

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Whitty

    2003-12-01

    The University of Utah project ''Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer'' (DOE award number DE-FC26-02NT41490) was developed in response to a solicitation for projects to provide technical support for black liquor and biomass gasification. The primary focus of the project is to provide support for a DOE-sponsored demonstration of MTCI's black liquor steam reforming technology at Georgia-Pacific's paper mill in Big Island, Virginia. A more overarching goal is to improve the understanding of phenomena that take place during low temperature black liquor gasification. This is achieved through five complementary technical tasks: (1) construction of a fluidized bed black liquor gasification test system, (2) investigation of bed performance, (3) evaluation of product gas quality, (4) black liquor conversion analysis and modeling and (5) computational modeling of the Big Island gasifier. Four experimental devices have been constructed under this project. The largest facility, which is the heart of the experimental effort, is a pressurized fluidized bed gasification test system. The system is designed to be able to reproduce conditions near the black liquor injectors in the Big Island steam reformer, so the behavior of black liquor pyrolysis and char gasification can be quantified in a representative environment. The gasification test system comprises five subsystems: steam generation and superheating, black liquor feed, fluidized bed reactor, afterburner for syngas combustion and a flue gas cooler/condenser. The three-story system is located at University of Utah's Industrial Combustion and Gasification Research Facility, and all resources there are available to support the research.

  10. Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Whitty

    2007-06-30

    University of Utah's project entitled 'Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer' (DOE Cooperative Agreement DE-FC26-02NT41490) was developed in response to a solicitation released by the U.S. Department of Energy in December 2001, requesting proposals for projects targeted towards black liquor/biomass gasification technology support research and development. Specifically, the solicitation was seeking projects that would provide technical support for Department of Energy supported black liquor and biomass gasification demonstration projects under development at the time.

  11. Experimental and numerical study of spouted bed fluif dynamics

    OpenAIRE

    C. R. Duarte; V. V. Murata; M. A. S. Barrozo

    2008-01-01

    Spouted beds, originally invented in Canada by Mathur and Gishler (1955) as an alternative to fluidized beds for handling coarse particles, are now widely studied in a variety of physical operations, such as drying, coating and granulation. In this work the particle velocity, minimum spouting flow rate and characteristic fluid-dynamic curves of the spouted bed were obtained using a Eulerian granular multiphase model. The computational work was significantly reduced for axisymmetric gas-solid ...

  12. Fluidized-bed calciner with combustion nozzle and shroud

    Science.gov (United States)

    Wielang, Joseph A.; Palmer, William B.; Kerr, William B.

    1977-01-01

    A nozzle employed as a burner within a fluidized bed is coaxially enclosed within a tubular shroud that extends beyond the nozzle length into the fluidized bed. The open-ended shroud portion beyond the nozzle end provides an antechamber for mixture and combustion of atomized fuel with an oxygen-containing gas. The arrangement provides improved combustion efficiency and excludes bed particles from the high-velocity, high-temperature portions of the flame to reduce particle attrition.

  13. Experimental and numerical study of spouted bed fluif dynamics

    Directory of Open Access Journals (Sweden)

    C. R. Duarte

    2008-03-01

    Full Text Available Spouted beds, originally invented in Canada by Mathur and Gishler (1955 as an alternative to fluidized beds for handling coarse particles, are now widely studied in a variety of physical operations, such as drying, coating and granulation. In this work the particle velocity, minimum spouting flow rate and characteristic fluid-dynamic curves of the spouted bed were obtained using a Eulerian granular multiphase model. The computational work was significantly reduced for axisymmetric gas-solid flows. The experimental data obtained in two spouted bed configurations, conical-cylindrical and two-dimensional, were compared with the simulated results, showing good agreement

  14. Temperature distribution and control in liquefied petroleum gas fluidized beds

    Institute of Scientific and Technical Information of China (English)

    Li Wang; Ping Wu; Yanping Zhang; Jing Yang; Lige Tong

    2004-01-01

    Temperature distribution and control have been investigated in a liquefied petroleum gas (LPG) fluidized bed with hollow corundum spheres (A12O3) of 0.867-1.212 mm in diameter at moderately high temperatures (800-1100℃). Experiments were carried out for the air consumption coefficient α in the range of 0.3 to 1.0 and the fluidization number N in the range of 1.3 to 3.0. Particle properties, initial bed height, α and N all affect temperature distribution in the bed. Bed temperature can be adjusted about 200℃ by combined the adjusting of α and N.

  15. Hydrodynamic and Heat Transfer Characteristics of Magnetofluidized Beds

    Institute of Scientific and Technical Information of China (English)

    S.C.Saxena; R.Z.Qian

    1994-01-01

    To investigate the flow and heat-transfer behaviors of magnetofluidized beds,an experimental facility was designed.A constant uniform magnetic field is produced by a Helmhotz electromagnet.The nature of fluidization and heat-transfer characteristics,of a horizontal electrically heated tube immersed in the bed were measured.The bed material is iron shots.Depending upon the intensity of magneticfield(weak,moderate and strong),the bed pressure drop and heat transfer coefficient are classified into three ranges of magnetic fields.The range of variation of maximum magnetic-field intensity is from 0 to about 20690 A/m.

  16. Anoxic environments and oil source bed genesis

    Energy Technology Data Exchange (ETDEWEB)

    Demaison, G.J. (Chevron Overseas Petroleum Inc., San Francisco, CA); Moore, G.T.

    1980-01-01

    The anoxic, aquatic, environment is a mass of water so depleted in oxygen that virtually all aerobic biological activity has ceased. Anoxic conditions occur where the demand for oxygen in the water column exceeds the supply. The specific cause for preferential lipid enrichment probably relates to the biochemistry of anaerobic bacterial activity. Recent evidence suggests that ancient organic-rich sediments containing hydrogen-rich kerogens (potential oil source beds) were deposited in similar anoxic environments. We propose the following classification for modern aquatic anoxic settings: (1) Large anoxic lakes - Permanent stratification promotes development of anoxic bottom water, particularly in large, deep lakes, which are not subject to seasonal overturn, e.g., Lake Tanganyika. (2) Anoxic silled basins - Landlocked silled basins with positive water balance tend to become anoxic. Typical are the Baltic and Black Seas. In arid region seas (Red and Mediterranean Seas), evaporation exceeds river inflow, causing negative water balance and well-aerated, nutrient-depleted bottom waters. (3) Anoxic layers caused by upwelling - Develop only when the oxygen supply in deep water cannot match demand by decaying organisms. Examples are the Benguela current and Peru coastal upwelling. (4) Open ocean anoxic layers - Found at intermediate depths in the northeastern Pacific and northern Indian Oceans; due to distance from deep, oxygenated polar water sources. Analogous to world-wide anoxic events at times of global climatic warm-ups and major transgressions, as in late Jurassic and middle Cretaceous time. Petroleum exploration can be greatly assisted by using geochemistry to identify paleo-anoxic events in the stratigraphic record. Recognition of the proposed anoxic models in ancient sedimentary basins should help in regional mapping of oil shales and oil-source beds. 17 figures.

  17. FIELD OBSERVATIONS ON BED SEDIMENTS AND SANDWAVES IN CHANGJIANG ESTUARY

    Institute of Scientific and Technical Information of China (English)

    Jiufa LI; Xinning WAN; Ming YING; Xiaohua CHEN

    2005-01-01

    A series of advanced instruments were applied to obtain the field data of bed, bed forms and relevant dynamic factors in the 150 km-long reach of the Changjiang River from Jiangyin to Hengsha Island in March 2002. We found that well-sorted fine sand was in the majority of the bed sediment, which had a median diameter of 2φ. Well-developed sandwaves were formed because the grains jumped together on the bed, which was related to the granularity and current velocity during the flood-ebb tidal cycles.

  18. Aspen shaving versus chip bedding: effects on breeding and behavior.

    Science.gov (United States)

    Jackson, E; Demarest, K; Eckert, W J; Cates-Gatto, C; Nadav, T; Cates, L N; Howard, H; Roberts, A J

    2015-01-01

    The choice of laboratory cage bedding material is often based on both practical and husbandry issues, whereas behavioral outcomes rarely appear to be considered. It has been noted that a breeding success difference appears to be associated with the differential use of aspen chip and aspen shaving bedding in our facility; therefore, we sought to analyze breeding records maintained over a 20-month period. In fact, in all four mouse strains analyzed, shaving bedding was associated with a significant increase in average weanlings per litter relative to chip bedding. To determine whether these bedding types also resulted in differences in behaviors associated with wellbeing, we examined nest building, anxiety-like, depressive-like (or helpless-like), and social behavior in mice housed on chip versus shaving bedding. We found differences in the nests built, but no overall effect of bedding type on the other behaviors examined. Therefore, we argue that breeding success, perhaps especially in more challenging strains, is improved on shaving bedding and this is likely due to improved nest-building potential. For standard laboratory practices, however, these bedding types appear equivalent.

  19. Digital image analysis measurements of bed expansion and segregation dynamics in dense gas-fluidized beds

    NARCIS (Netherlands)

    Goldschmidt, M.J.V.; Link, J.M.; Mellema, S.; Kuipers, J.A.M.

    2003-01-01

    One of the most crucial steps in the development of fundamental hydrodynamic models is the validation of these models with accurate, detailed experimental data. Therefore a whole-field, non-intrusive digital image analysis technique has been developed which enables measurement of bed expansion and s

  20. The impact of bed temperature on heat transfer characteristic between fluidized bed and vertical rifled tubes

    Science.gov (United States)

    Blaszczuk, Artur; Nowak, Wojciech

    2016-10-01

    In the present work, the heat transfer study focuses on assessment of the impact of bed temperature on the local heat transfer characteristic between a fluidized bed and vertical rifled tubes (38mm-O.D.) in a commercial circulating fluidized bed (CFB) boiler. Heat transfer behavior in a 1296t/h supercritical CFB furnace has been analyzed for Geldart B particle with Sauter mean diameter of 0.219 and 0.246mm. The heat transfer experiments were conducted for the active heat transfer surface in the form of membrane tube with a longitudinal fin at the tube crest under the normal operating conditions of CFB boiler. A heat transfer analysis of CFB boiler with detailed consideration of the bed-to-wall heat transfer coefficient and the contribution of heat transfer mechanisms inside furnace chamber were investigated using mechanistic heat transfer model based on cluster renewal approach. The predicted values of heat transfer coefficient are compared with empirical correlation for CFB units in large-scale.

  1. The Influence of Salmonid Spawning on Grain Architecture, Critical Bed Shear Stress, and Bed Load Transport in Streams

    Science.gov (United States)

    Buxton, T.; Buffington, J. M.; Yager, E. M.; Fremier, A. K.; Hassan, M. A.

    2012-12-01

    Salmonid spawning occurs in many high to mid-order streams in North America and Europe, but the detailed mechanics of this disturbance on stream bed mobility is not well studied. We calculated and measured spawning effects on incipient bed mobility and sediment transport in a laboratory flume and found that the tailspill portion of simulated spawning nests ("redds") are less stable than unspawned beds. This result agrees with field research by others, but counters prior calculations of tailspill stability that used grain architecture relationships derived from unspawned beds. Redds have coarser and better sorted surfaces, which reduce grain exposure and protrusion compared to unspawned beds, but load cell measurements of the total resistance to movement of grains on redds were lower despite deeper grain pockets and larger pivot angles. This is because the redd-building process flushed fine sediment that had previously cemented bed material, resulting in a looser bed structure and more mobile grains. These observations are supported by force balance calculations of critical shear stress on redds being lower on average than on unspawned beds. Computational results are supported by visual observations and measurements of bed load transport from redds and unspawned beds in the flume, where redds mobilized sooner and exhibited a higher sediment transport rate than unspawned beds. Redds were observed to erode by translating, then dispersing and evacuating downstream, before grains on the unspawned bed mobilized. Further increase in discharge mobilized greater proportions of the unspawned bed but did not scour the deeper portion of redds where spawners deposit their eggs. Our results suggest both an evolutionary trade-off and advantage to large spawning populations. Namely, the structurally loose tailspill likely increases intragravel flow to eggs at the expense of tailspill instability, which may sufficiently elevate sediment yields in streams with high spawner densities

  2. Soft-bed experiments beneath Engabreen, Norway: Regelation, infiltration, basal slip and bed deformation

    Science.gov (United States)

    Iverson, N.R.; Hooyer, T.S.; Fischer, U.H.; Cohen, D.; Moore, P.L.; Jackson, M.; Lappegard, G.; Kohler, J.

    2007-01-01

    To avoid some of the limitations of studying soft-bed processes through boreholes, a prism of simulated till (1.8 m ?? 1.6 m ?? 0.45 m) with extensive instrumentation was constructed in a trough blasted in the rock bed of Engabreen, a temperate glacier in Norway. Tunnels there provide access to the bed beneath 213 m of ice. Pore-water pressure was regulated in the prism by pumping water to it. During experiments lasting 7-12 days, the glacier regelated downward into the prism to depths of 50-80 mm, accreting ice-infiltrated till at rates predicted by theory. During periods of sustained high pore-water pressure (70-100% of overburden), ice commonly slipped over the prism, due to a water layer at the prism surface. Deformation of the prism was activated when this layer thinned to a sub-millimeter thickness. Shear strain in the till was pervasive and decreased with depth. A model of slip by ploughing of ice-infiltrated till across the prism surface accounts for the slip that occurred when effective pressure was sufficiently low or high. Slip at low effective pressures resulted from water-layer thickening that increased non-linearly with decreasing effective pressure. If sufficiently widespread, such slip over soft glacier beds, which involves no viscous deformation resistance, may instigate abrupt increases in glacier velocity.

  3. Simulation Facilities and Test Beds for Galileo

    Science.gov (United States)

    Schlarmann, Bernhard Kl.; Leonard, Arian

    2002-01-01

    Galileo is the European satellite navigation system, financed by the European Space Agency (ESA) and the European Commission (EC). The Galileo System, currently under definition phase, will offer seamless global coverage, providing state-of-the-art positioning and timing services. Galileo services will include a standard service targeted at mass market users, an augmented integrity service, providing integrity warnings when fault occur and Public Regulated Services (ensuring a continuity of service for the public users). Other services are under consideration (SAR and integrated communications). Galileo will be interoperable with GPS, and will be complemented by local elements that will enhance the services for specific local users. In the frame of the Galileo definition phase, several system design and simulation facilities and test beds have been defined and developed for the coming phases of the project, respectively they are currently under development. These are mainly the following tools: Galileo Mission Analysis Simulator to design the Space Segment, especially to support constellation design, deployment and replacement. Galileo Service Volume Simulator to analyse the global performance requirements based on a coverage analysis for different service levels and degrades modes. Galileo System Simulation Facility is a sophisticated end-to-end simulation tool to assess the navigation performances for a complete variety of users under different operating conditions and different modes. Galileo Signal Validation Facility to evaluate signal and message structures for Galileo. Galileo System Test Bed (Version 1) to assess and refine the Orbit Determination &Time Synchronisation and Integrity algorithms, through experiments relying on GPS space infrastructure. This paper presents an overview on the so called "G-Facilities" and describes the use of the different system design tools during the project life cycle in order to design the system with respect to

  4. Bed bug detection: Current technologies and future directions

    Science.gov (United States)

    This study evaluates current technologies used to detect bed bug infestations, and presents new information regarding the underlying chemical basis of canines scent detection. The manuscript also reports new and future devices that may play a part in bed bug detection in the future....

  5. Streamline curvature and bed resistance in shallow water flow

    NARCIS (Netherlands)

    De Vriend, H.J.

    1979-01-01

    The relationship between streamline curvature and bed resistance in shallow water flow with little side constraint, as derived in 1970 by H.J. Schoemaker, is reconsidered. Schoemaker concluded that the bed resistance causes the curvature of a free streamline to grow exponentially with the distance a

  6. Particle transport in fluidized beds : experiments and stochastic models

    NARCIS (Netherlands)

    Dechsiri, Chutima

    2004-01-01

    Fluidization is a process in which solids are caused to behave like fluid by blowing gas or liquid upwards through the solid-filled reactor. The behavior of a bed of particles within the reactor during the process is very complex and difficult to predict. To make sure that a fluidized bed reactor is

  7. Lithofacies and petrophysical properties of Portland Base Bed and Portland Whit Bed limestone as related to durability

    NARCIS (Netherlands)

    Dubelaar, C.W.; Engering, S.; Hees, R.P.J. van; Koch, R.; Lorenz, H.G.

    2003-01-01

    This study focuses on the differences in lithofacies and petrophysical properties of Base Bed and Whit Bed Portland limestone and the presumed relationships between these characteristics and the durability of this building stone. As Portland limestone probably will be used as a stone for several res

  8. Lithofacies and Petrophysical Properties of Portland Base Bed and Portland Whit Bed Limestone as Related to Durability

    NARCIS (Netherlands)

    Dubelaar, C.W.; Engering, S.; Van Hees, R.P.J.; Koch, R.; Lorenz, H.G.

    2003-01-01

    This study focuses on the differences in lithofacies and petrophysical properties of Base Bed and Whit Bed Portland limestone and the presumed relationships between these characteristics and the durability of this building stone. As Portland limestone probably will be used as a stone for several res

  9. Achievements of China's Coal-bed Methane Exploration and Development

    Institute of Scientific and Technical Information of China (English)

    Zhao Qingbo; Tian Wenguang

    2008-01-01

    @@ Status quo of China's coal-bed methane exploration and development China's coal-bed methane resources China is abundant in coal-bed methane. The new round of resource assessment indicates that 119 potential coal-bed methane targets with burial depth of 2000m and area of 41.5×104km2 are distributed in more than 45 coal-bearing basins. The total resources of coal-bed methane is almost equivalent to that of conventional gas, ranking the third in the world. Among the basins, there are 8 has a coverage of more than 1×1012m3, they are Yili, Tuha,Ordos, Dianqiangui, Juggar, Hailaer, Erlian, and Qinshui.

  10. Pebble bed pebble motion: Simulation and Applications

    CERN Document Server

    Cogliati, Joshua J

    2011-01-01

    This dissertation presents a method for simulation of motion of the pebbles in a PBR. A new mechanical motion simulator, PEBBLES, efficiently simulates the key elements of motion of the pebbles in a PBR. This model simulates gravitational force and contact forces including kinetic and true static friction. It's used for a variety of tasks including simulation of the effect of earthquakes on a PBR, calculation of packing fractions, Dancoff factors, pebble wear and the pebble force on the walls. The simulator includes a new differential static friction model for the varied geometries of PBRs. A new static friction benchmark was devised via analytically solving the mechanics equations to determine the minimum pebble-to-pebble friction and pebble-to-surface friction for a five pebble pyramid. This pyramid check as well as a comparison to the Janssen formula was used to test the new static friction equations. Because larger pebble bed simulations involve hundreds of thousands of pebbles and long periods of time, P...

  11. Effect of bed temperature and bed composition on agglomeration during gasification of high-sodium, high-sulphur lignite in a spouted fluidised bed

    Energy Technology Data Exchange (ETDEWEB)

    D.P. McCullough; P.J. Mullinger; P.J. Ashman [University of Adelaide, Adelaide, SA (Australia). Cooperative Research Centre for Clean Power from Lignite, School of Chemical Engineering

    2003-07-01

    Fluidised bed gasification (FBG) is an alternative process for coal utilisation that delivers improved efficiencies and lower temperature operation compared to conventional technology. Agglomeration and defluidisation are phenomena that have the potential to occur within fluidised bed reactors, which can interrupt stable process operation. While extensive work has been carried out investigating fluidised bed combustion of lignite, relatively little work has been carried out for lignite under fluidised bed gasification conditions. Gasification of high sodium, high sulphur content lignite in a spouted bed gasifier (SBG) indicates that agglomeration and defluidisation is only an issue when maximum bed temperature exceeds approximately 850{degree}C and air/fuel ratios of 2.5 outside of these conditions, defluidisation is not detected. It is also demonstrated that defluidisation occurs before agglomeration, rather than as a result of agglomeration as previously thought. The Rosin-Rammler method of describing particle size distribution is found to yield appropriate variables for quantification of the extent of agglomeration taking place in cases where defluidisation is a factor. However, it has been shown by this method that while initial results indicated that agglomeration extent varies directly with maximum bed temperature, further results have shown that other variables, such as superficial velocity, have a significant impact on the extent of agglomeration. Investigations are currently continuing. 9 refs., 8 figs., 9 tabs.

  12. Predicting bed load transport of sand and gravel on Goodwin Creek

    Science.gov (United States)

    Bed load transport rates are difficult to predict in channels with bed material composed of sand and gravel mixtures. The transport of bed load was measured on Goodwin Creek, and in a laboratory flume channel with a similar bed material size distribution. The range of bed load transport rates meas...

  13. Expanded and packed bed albumin adsorption on fluoride modified zirconia.

    Science.gov (United States)

    Mullick, A; Griffith, C M; Flickinger, M C

    1998-11-01

    The expanded bed characteristics of 75-103microm fluoride-modified zirconia (FmZr) particles synthesized by a fed batch oil emulsion process were investigated. These particles are distinguished from commercially available expanded-bed adsorbents by virtue of their high density (2.8 g/cc) and the mixed mode protein retention mechanism which allows for the retention of both cationic and anionic proteins. The linear velocity versus bed porosity data agree with the Richardson-Zaki relationship with the terminal velocity in infinite medium of 2858.4 cm/h and a bed expansion index of 5.1. Residence time distribution (RTD) studies and bovine serum albumin (BSA) adsorption studies were performed as a function of the height of the settled bed to the column diameter (H:D) ratio and degree of bed expansion with superficial velocities of 440 to 870 cm/h. The settled bed, a 2x expanded bed, and a 3x expanded bed were studied for the H:D ratios of 1:1, 2:1, and 3:1. The dynamic binding capacity (DBC) at 5% breakthrough was low (2-8 mg BSA/mL settled bed) and was independent of the H:D ratio or the degree of bed expansion. The saturation DBC was 32.3 +/- 7.0 mg BSA/mL settled bed. The adsorption-desorption kinetics and intraparticle diffusion for protein adsorption on FmZr (38-75 micrometer) were investigated by studying the packed bed RTD and BSA adsorption as a function of temperature and flow rate. The data show that the adsorption-desorption kinetics along with intraparticle diffusion significantly influence protein adsorption on FmZr. Low residence times ( approximately 0.8 min) of BSA result in a DBC at 5% breakthrough which is 3.5-fold lower compared to that at 6-fold higher protein residence time. At low linear velocity (45 cm/h) the breakthrough curve is nearly symmetrical and becomes asymmetrical and more dispersed at higher linear velocity (270 cm/h) due to the influence of slow adsorption-desorption kinetics and intraparticle diffusion. Bioeng 60: 333-340, 1998. PMID

  14. Experimental studies and CFD simulations of conical spouted bed hydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z.

    2008-07-01

    This thesis involved both experimental research and mathematical modelling of the hydrodynamics of conical spouted beds. Although conical spouted beds are commonly used for drying suspensions, solutions and pasty materials, they can also be used for catalytic partial oxidation of methane to synthesis gas, coal gasification and liquefaction, and pyrolysis of sawdust. Pressure transducers and static pressure probes were used in the experimental studies to investigate the evolution of the internal spout and the local static pressure distribution. Optical fibre probes were used to measure axial particle velocity profiles and voidage profiles. The gas mixing behaviour inside a conical spouted bed was examined using a step trace injection technique in which helium was used as the tracer and thermal conductivity cells were used as the detectors. For the mathematical modelling, a stream-tube model based on the bed structure inside a conical spouted bed was proposed to simulate partial spouting states. An adjustable parameter was introduced into the model to enable total pressure drop prediction under different operating conditions, and to estimate axial superficial gas velocity profiles and gauge pressure profiles. A mathematical model based on characteristics of conical spouted beds and FLUENT software was also developed and validated using measured experimental data. The proposed CFD model can simulate both stable spouting and partial spouting states, with an adjustable solids-phase source term. The effect of all possible factors on simulation results were investigated, including the fluid inlet profile, solid bulk viscosity, frictional viscosity, restitution coefficient, exchange coefficient, and solid phase source term. In addition to simulating the gas mixing behaviours inside a conical spouted bed, the new CFD model simulated cylindrical packed beds and cylindrical fluidized beds in one code package.

  15. Heat-transfer characteristics of flowing and stationary particle-bed-type fusion-reactor blankets

    Energy Technology Data Exchange (ETDEWEB)

    Nietert, R.E.

    1983-02-01

    The following five appendices are included: (1) physical properties of materials, (2) thermal entrance length Nusselt number variations, (3) stationary particle bed temperature variations, (4) falling bed experimental data and calculations, and (5) stationary bed experimental data and calculations. (MOW)

  16. Ancient ice streams and their megalineated beds

    Science.gov (United States)

    Eyles, Nick; Ross, Martin

    2016-06-01

    Ice streams are corridors of fast-flowing (~ 800 m yr- 1) ice inset within otherwise sluggish-moving ice sheets. According to reported estimates, as much as 90% of the total discharge of the Antarctic Ice Sheet, for example, occurs through such corridors. Recognition of ice stream records in paleo-ice sheet research has profoundly changed the discipline of glacial geology. The key has been identification of the distinctive corrugated or 'megalineated' geomorphology of their beds, consisting of elongate ridges that are parallel to ice flow direction and often transitional to drumlins. Access to new satellite imagery has enabled mapping of megascale glacial lineations (MSGLs) over large swaths of terrain and the recognition of regional-scale ice stream flow paths and origins. At the peak of the last ice age, just after 20,000 years ago, there were more than 100 ice streams within the Laurentide Ice Sheet. Only now are we beginning to fully appreciate the fundamental role that such streams (which have been called the 'arteries' of ice sheets) have had on glaciated landscapes, by moving enormous volumes of sediment and releasing armadas of floating ice to the Arctic and Atlantic oceans. There is also a growing awareness of the erosional role of ice streams in overdeepening of lakes, fiords and other troughs along coastlines. Much remains to be learnt and new discoveries surely await. The picture of past ice sheets, like the Laurentide and Fennoscandian Ice Sheets, that is emerging today is very different from that of 20 years ago.

  17. A DU bed system for storing and supplying hydrogen isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Daeseo; Park, Jongchul; Ahn, Do-Hee; Chung, Hongsuk [KAERI, Daejeon (Korea, Republic of); Yun, Sei-Hun [National Fusion Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Depleted uranium (DU) has been extensively proposed for the storage, supply, and recovery of hydrogen isotopes. SDS is used for storing hydrogen isotopes as a metal hydride form. To control the SDS, it is necessary to monitor the tritium amount in a bed. In this study, a full-sized DU bed was designed and fabricated including cylindrical-type copper foam of nine layers to study the characteristics of hydriding/dehydriding and simulate the tritium amount in a bed. The integrity and leak inspection on the welding of a primary vessel was performed using a penetration test, helium leak test, and pressure test. Auto tuning on the cable heaters of two pairs in the DU bed was also be performed. In our next study, the hydriding/dehydriding on a DU bed will be performed. A simulation on the depleted uranium hydriding will be carried out. A DU bed was designed and fabricated including cylindrical-type copper foam of nine layers to study the characteristics of hydriding/dehydriding and simulate the tritium amount in a bed. Through a penetration test, it was confirmed that the welding of the primary vessel has a good integrity. It was confirmed that the two helium tubes is sound by inspecting a helium leak test on the welding of the primary vessel. It was also confirmed that the primary vessel has a good integrity by inspecting a helium leak and conducting a pressure test on it. Vacuuming of the DU bed system was carried out. Vacuuming of the in-bed calorimetric equipment was also carried out.

  18. Coal bed methane potential and biogasification of soma lignite

    OpenAIRE

    Baysal, Mustafa

    2012-01-01

    Coal bed methane (CBM) can arise from both thermogenic and biogenic activity on the coal beds and adsorb on the porous matrix of the coal. Therefore, investigation of pore structure and gas capacity of the coal is essential for accurate estimations of coal bed gas potential. Coal samples of lignite to sub-bituminous rank were obtained from different depths of Soma basin and were characterized by low pressure CO2 adsorption isotherms at 273 K. Micropore surface areas of the samples were calcul...

  19. Sunlamps and Sunlamp Products (Tanning Beds/Booths)

    Science.gov (United States)

    ... Radiation-Emitting Products and Procedures Home, Business, and Entertainment Products Sunlamps and Sunlamp Products (Tanning Beds/Booths) Share ... PDF - 71KB) [ARCHIVED] More in Home, Business, and Entertainment Products Cell Phones Health Issues Reducing Exposure: Hands-free ...

  20. Nitrification in moving bed and fixed bed biofilters treating effluent water from a large commercial outdoor rainbow trout RAS

    DEFF Research Database (Denmark)

    Suhr, Karin; Pedersen, Per Bovbjerg

    2010-01-01

    The nitrification performance of two fixed bed (FB) biofilters and two moving bed (MB) biofilters was evaluated. They received the same cold (8 degrees C) influent water from a commercial outdoor RAS facility producing rainbow trout (average density 32 kg m(-3)). The filters were constructed...

  1. Flow and combustion characteristics of a 2-dimensional spouted bed

    Science.gov (United States)

    Sawyer, R. F.; Hart, J. R.; Ohtake, K.

    1982-03-01

    A two dimensional spouted bed laboratory combustor was designed and constructed with the objective of studying the interaction among the gas flow, particle flow, and combustion. The facility, designed for a maximum thermal power of 20 kW, has a quartz front wall providing full optical access to particle flows and combustion processes. The combustor was characterized in terms of pressure, temperature, gas velocity, and particle velocity profiles and operating limits. Initial studies employed premixed propane and air and a fixed bed height, bed material, injector slot width, and combustor geometry. As in previous investigations of axisymmetric spouted beds, the ratio of particle mass circulation rate to jet mass flow rate was observed to be about ten. Combustion increased this ratio by about 10%. A pulsating mode of operation was noted with a characteristic frequency of about 10 Hz, controlled by the interaction of the particle and gas flows.

  2. RELATING WEIGHT AND COUNT DISTRIBUTIONS OF STREAM BED GRAVEL

    Science.gov (United States)

    The size distribution of particles in a stream bed reflects the stream hydrology as well as its physical and chemical water quality characteristics. In environmental assessments, gravel distribution determines habitat quality for aquatic insects and stream suitability for spawnin...

  3. [Patient-related color preference and color design in the hospital].

    Science.gov (United States)

    Schuschke, G; Christiansen, H

    1994-06-01

    Colour-physiological studies involving volunteers and colour-psychological interviewing of patients with varied diagnoses revealed that, currently, no compelling scientific reasons can be given for coloration in the hospital. Interviewing 68 patients from a number of clinics on the coloration of sick-rooms yielded the following preferred colours, irrespective of the patients' classing into groups by various criteria: Light colours were consistently preferred for all objects such as ceiling, walls, floor, curtains, furniture, and bed linen. It should be emphasized that even white was a desirable colour for ceilings and bed linen. Beige was found to rank first for walls, floors, curtains, and furniture, whereas the colours of wood and grey shared the second rank for floors and furniture. Green and pink ranked second for bed linen. White and green ranked second for walls and curtains, respectively. In view of the heterogeneity, the findings may not be converted into an absolute just as the recommendations by other workers. Still, the patients' wish should be given priority over decreed recommendations by experts when basic considerations of illumination (reflectance!) are allowed for in the particular overall colour design project. PMID:7916869

  4. Northern and Central Appalachian region assessment: The Pittsburgh coal bed

    Energy Technology Data Exchange (ETDEWEB)

    Ruppert, L.; Tewalt, S.; Bragg, L. [Geological Survey, Reston, VA (United States)

    1996-12-31

    Approximately 40% of the Nation`s coal is produced in the six states (Ohio, Pennsylvania, West Virginia, Maryland, Virginia, and Kentucky) that occupy parts of the Northern and Central Appalachian region. Coal is, and will continue to be, the primary energy commodity in this region where more than 50 coal beds and coal zones are currently being mined. About one-half of the productions is from just eight coal beds or zones. Three of these, the Pittsburgh and Upper Freeport coal beds and the Kittanning coal zone, are located in the northern part of the region. The remaining beds or zones, the Pond Creek, Fire Clay, Alma, Upper Elkhorn No. 3, and the Pocahontas No. 3, are located primarily in the central part of the region. This study is designed to utilize the data and expertise existing within the USGS and the State Geological Surveys to produce bed-specific, digital, coal resource assessments for most of the top-producing coal beds and coal zones. Unlike past USGS assessments, this study will emphasize not only the quantity of coal but also the quality of the coal. Particular attention will be paid to the geochemical parameters that are thought to adversely effect combustion characteristics and possibly have adverse effects on the environment, including ash yield, sulfur, calorific value, and, the elements listed in the 1990 Clean Air Act Amendments. Geochemical databases produced for the assessed beds will be augmented by new, representative, coal analyses of major, minor, and trace elements. Products will include stratigraphic and geochemical data bases, original and remaining source calculations, and comprehensive digital maps at a scale of 1:250,000 or 1:500,000 of crop-line, coal thickness, coal structure, overburden thickness, mined-out areas, and geochemistry for each assessed coal beds.

  5. Model of Fluidized Bed Containing Reacting Solids and Gases

    Science.gov (United States)

    Bellan, Josette; Lathouwers, Danny

    2003-01-01

    A mathematical model has been developed for describing the thermofluid dynamics of a dense, chemically reacting mixture of solid particles and gases. As used here, "dense" signifies having a large volume fraction of particles, as for example in a bubbling fluidized bed. The model is intended especially for application to fluidized beds that contain mixtures of carrier gases, biomass undergoing pyrolysis, and sand. So far, the design of fluidized beds and other gas/solid industrial processing equipment has been based on empirical correlations derived from laboratory- and pilot-scale units. The present mathematical model is a product of continuing efforts to develop a computational capability for optimizing the designs of fluidized beds and related equipment on the basis of first principles. Such a capability could eliminate the need for expensive, time-consuming predesign testing.

  6. ADVANCED SORBENT DEVELOPMENT PROGRAM DEVELOPMENT OF SORBENTS FOR MOVING-BED AND FLUIDIZED-BED APPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    R.E Ayala; V.S. Venkataramani; Javad Abbasian; Rachid B. Slimane; Brett E. Williams; Minoo K. Zarnegar; James R. Wangerow; Andy H. Hill

    2000-03-31

    The integrated gasification combined cycle (IGCC) power system using high-temperature coal gas cleanup is one of the most promising advanced technologies for the production of electric power from coal in an environmentally acceptable manner. Unlike conventional low-temperature cleanup systems that require costly heat exchangers, high-temperature coal gas cleanup systems can be operated near 482-538 C (900-1000 F) or higher, conditions that are a closer match with the gasifier and turbine components in the IGCC system, thus resulting is a more efficient overall system. GE is developing a moving-bed, high-temperature desulfurization system for the IGCC power cycle in which zinc-based regenerable sorbents are currently being used as desulfurization sorbents. Zinc titanate and other proprietary zinc-based oxides are being considered as sorbents for use in the Clean Coal Technology Demonstration Program at Tampa Electric Co.'s (TECo) Polk Power Station. Under cold startup conditions at TECo, desulfurization and regeneration may be carried out at temperatures as low as 343 C (650 F), hence a versatile sorbent is desirable to perform over this wide temperature range. A key to success in the development of high-temperature desulfurization systems is the matching of sorbent properties for the selected process operating conditions, namely, sustainable desulfurization kinetics, high sulfur capacity, and mechanical durability over multiple cycles. Additionally, the sulfur species produced during regeneration of the sorbent must be in a form compatible with sulfur recovery systems, such as sulfuric acid or elemental sulfur processes. The overall objective of this program is to develop regenerable sorbents for hydrogen sulfide removal from coal-derived fuel gases in the temperature range 343-538 C (650-1000 F). Two categories of reactor configurations are being considered: moving-bed reactors and fluidized-bed (bubbling and circulating) reactors. In addition, a cost

  7. Advanced sorbent development progam; development of sorbents for moving-bed and fluidized-bed applications

    International Nuclear Information System (INIS)

    The integrated gasification combined cycle (IGCC) power system using high-temperature coal gas cleanup is one of the most promising advanced technologies for the production of electric power from coal in an environmentally acceptable manner. Unlike conventional low-temperature cleanup systems that require costly heat exchangers, high-temperature coal gas cleanup systems can be operated near 482-538 C (900-1000F) or higher, conditions that are a closer match with the gasifier and turbine components in the IGCC system, thus resulting is a more efficient overall system. GE is developing a moving-bed, high-temperature desulfurization system for the IGCC power cycle in which zinc-based regenerable sorbents are currently being used as desulfurization sorbents. Zinc titanate and other proprietary zinc-based oxides are being considered as sorbents for use in the Clean Coal Technology Demonstration Program at Tampa Electric Co.s (TECo) Polk Power Station. Under cold startup conditions at TECo, desulfurization and regeneration may be carried out at temperatures as low as 343 C (650 F), hence a versatile sorbent is desirable to perform over this wide temperature range. A key to success in the development of high-temperature desulfurization systems is the matching of sorbent properties for the selected process operating conditions, namely, sustainable desulfurization kinetics, high sulfur capacity, and mechanical durability over multiple cycles. Additionally, the sulfur species produced during regeneration of the sorbent must be in a form compatible with sulfur recovery systems, such as sulfuric acid or elemental sulfur processes. The overall objective of this program is to develop regenerable sorbents for hydrogen sulfide removal from coal-derived fuel gases in the temperature range 343-538 C (650-1000 F). Two categories of reactor configurations are being considered: moving-bed reactors and fluidized-bed (bubbling and circulating) reactors. In addition, a cost assessment and

  8. Limestone fragmentation and attrition during fluidized bed oxyfiring

    Energy Technology Data Exchange (ETDEWEB)

    Fabrizio Scala; Piero Salatino [Istituto di Ricerche sulla Combustione - CNR, Napoli (Italy)

    2010-04-15

    Attrition/fragmentation of limestone under simulated fluidized bed oxyfiring conditions was investigated by means of an experimental protocol that had been previously developed for characterization of attrition/fragmentation of sorbents in air-blown atmospheric fluidized bed combustors. The protocol was based on the use of different and mutually complementary techniques. The extent and pattern of attrition by surface wear in the dense phase of a fluidized bed were assessed in experiments carried out with a bench scale fluidized bed combustor under simulated oxyfiring conditions. Sorbent samples generated during simulated oxyfiring tests were further characterized from the standpoint of fragmentation upon high velocity impact by means of a purposely designed particle impactor. Results showed that under calcination-hindered conditions attrition and fragmentation patterns are much different from those occurring under air-blown atmospheric combustion conditions. Noteworthy, attrition/fragmentation enhanced particle sulfation by continuously regenerating the exposed particle surface. 13 refs., 8 figs.

  9. BED UTILIZATION IN CARDIO VASCULAR AND THORACIC SURGERY WARD

    Directory of Open Access Journals (Sweden)

    Ishtyak

    2015-11-01

    Full Text Available BACKGROUND: Of all the subsystems of a hospital, inpatient care occupies prime place in terms of resource consumed, use of specialized technical man power, technology and skill. In spite of the huge investment of money, material and the manpower at times even the basic needs of patients are not met. AIMS: The study was conducted, to observe the average length of stay (ALS of patients in cardio vascular and thoracic Surgery (CVTS ward, and to find out the bed occupancy rate. METHODS: The admission and discharge record of all the patients was recorded from the report books, hospital files of all the patients were checked to know complete biodata. Medical record section was consulted and admission discharge register/files were recorded to know the symptomatology, clinical findings, diagnosis and the management thereof. Mortality and morbidity was recorded from admission files. RESULTS: A total of 732 patients were admitted on a bed complement of 11712 days having 8639 bed days. 84.28% of the patients underwent surgical procedures. Daily average beds occupied were 23.60 beds per day, average length of stay was 11.23 days, and 73.76% was the bed occupancy rate. CONCLUSION: Patients having major operations had more length of stay compared to patients who were admitted after pre anesthetic checkup and full planning from outdoor departments. Preadmission evaluation, pre anesthetic checkup and preventing post-operative morbidity decrease length of stay

  10. Bed capacity and surgical waiting lists: a simulation analysis

    Directory of Open Access Journals (Sweden)

    Manel Antelo

    2015-12-01

    Full Text Available Waiting time for elective surgery is a key problem in the current medical world. This paper aims to reproduce, by a Monte Carlo simulation model, the relationship between hospital capacity, inpatient activity, and surgery waiting list size in teaching hospitals. Inpatient activity is simulated by fitting a Normal distribution to real inpatient activity data, and the effect of the number of beds on inpatient activity is modelled with a linear regression model. Analysis is performed with data of the University Multi-Hospital Complex of Santiago de Compostela (Santiago de Compostela, Spain, by considering two scenarios regarding the elastiticity of demand with bed increase. If demand does not grow with an increase on bed capacity, small changes lead to drastic reductions in the waiting lists. However, if demand grows as bed capacity does, adding additional capacity merely makes waiting lists worse.

  11. Properties of Concrete Incorporating Bed Ash from Circulating Fluidized Bed Combustion and Ground Granulates Blast-furnace Slag

    Institute of Scientific and Technical Information of China (English)

    CHENG An; HSU Hui-Mi; CHAO Sao-Jeng

    2011-01-01

    The properties of concrete incorporating circulating fluidized bed combustion (CFBC) bed ash and ground granulates blast-furnace slag (GGBS) were studied. Compressive strength,drying shrinkage, mercury intrusion porosimetry (MIP), scanning electronic microscopy (SEM), and X-ray diffraction (XRD) of concrete samples containing CFBC bed ash and GGBS were used. This work used initial surface absorption test (ISAT) and rapid chloride penetration test (RCPT) on concrete to measure the absorption and the ability of concrete to resist chloride ion characteristics for different concrete samples containing CFBC bed ash and GGBS. Open circuit potential (OCP), direct current polarization resistance were obtained to evaluate rebar corrosion. The CFBC bed ash was X-ray amorphous and consist of SiO2, A12O3 and CaO compounds. As the replacement of CFBC for sand increases, the rate of initial surface absorption (ISA) increases but compressive strength decreases.When the content of CFBC bed ash replacement for sand maintains constant, the replacement of GGBS for cement increases, compressive strength increases but the rate of ISA decreases. Chloride and corrosion resistance of rebar significantly improve by utilizing a proper amount of CFBC bed ash and GGBS in concrete.

  12. Bed occupancy rates and hospital-acquired infections--should beds be kept empty?

    Science.gov (United States)

    Kaier, K; Mutters, N T; Frank, U

    2012-10-01

    There is growing evidence that bed occupancy (BO) rates, overcrowding and understaffing influence the spread of hospital-acquired infections (HAIs). In this article, a systematic review of the literature is presented, summarizing the evidence on the adverse effects of high BO rates and overcrowding in hospitals on the incidence of HAIs. A Pubmed database search identified 179 references, of which 44 were considered to be potentially relevant for full-text review. The majority (62.9%) focused on methicillin-resistant Staphylococcus aureus-associated infection or colonization. Only 12 studies were found that provided a statistical analysis of the impact of BO on HAI rates. The median BO rate of the analysed studies was 81.2%. The majority of studies (75%) indicated that BO rates and understaffing directly influence the incidence of HAIs. Only three studies showed no significant association between BO rates and the incidence of HAIs. Interestingly, only one of the included studies detected a seasonal trend in the BO rate. The present review shows an association between BO rates and the spread of HAIs in various settings. Because the evidence on this topic is limited, we conclude that further research is needed in order to analyse the rationale of a threshold BO rate, because keeping beds empty is comparatively costly.

  13. Acidification of calf bedding reduces fly development and bacterial abundance.

    Science.gov (United States)

    Calvo, M S; Gerry, A C; McGarvey, J A; Armitage, T L; Mitloehner, F M

    2010-03-01

    Environmental stressors, such as high fly density, can affect calf well-being. Sodium bisulfate (SBS) is an acidifier that reduces the pH of flooring and bedding, creating a medium that neither bacteria nor immature flies (also known as larvae or maggots) can thrive in. Two experiments were conducted to investigate the application of SBS to a mixture of rice hull calf bedding and calf slurry (BED) to reduce house fly (Musca domestica L.) larval density and the abundance of bacteria. In experiment 1, dish pans containing 1L of BED and 3,000 house fly eggs were treated with SBS at concentrations of 0, 8.9, 17.7, and 26.5g of SBS/0.05m(2) of BED (CON, LOW, MED, and HIGH, respectively), with each SBS concentration applied to 4 individual pans (16 pans total). Reapplication of the same SBS concentrations in each pan occurred 3 times/wk throughout the 23-d trial. Larval house fly survival was significantly reduced in all pans with SBS relative to CON pans, with lowest survival rates in the MED and HIGH pans (99% and 100% reduction, respectively). The mean pH for each treatment was inversely related to the SBS concentration. In experiment 2, pans containing 1L of BED and 3,000 house fly eggs were treated with either 0g of SBS (CON), 8.9g of SBS/0.05m(2) of BED with reapplication of the acidifier 3 times/wk (SB3x), or 8.9g of SBS/0.05m(2) of BED applied only once at 48h before the end of the 8 d-trial (SB48). Larval house fly survival and bacterial concentrations were reduced (90% larval reduction and 68% bacterial reduction) in the SB3x treatment relative to the CON. Mean pH was also reduced in SB3x pans relative to CON or SB48 pans. Overall, acidification of calf BED using the acidifier SBS resulted in a reduction of bacteria and house fly larval survival. This form of fly control might be expected to reduce adult fly production and, therefore, fly-related stress in calves.

  14. Performance comparison of suspended bed and batch contactor chromatography.

    Science.gov (United States)

    Quiñones-García, I; Rayner, I; Levison, P R; Dickson, N; Purdom, G

    2001-01-26

    In some applications, the purification and recovery of biomolecules is performed via a cascade of batch adsorption and desorption stages using agitated contactors and related filtration devices. Suspended bed chromatography is a recent process-scale innovation that is applicable to these separations. This hybrid technique exploits the benefits of combining batch adsorption in an agitated contactor with elution in an enclosed column system. To some extent, the process is similar to batch contactor chromatography but can be fully contained and significantly quicker. The process has two steps; first the fluid containing the sample is mixed with the adsorbent in a stirred tank. Second, the slurry suspension is transferred directly into a specialized column, such as an IsoPak column. The media with the adsorbed product is formed as a packed bed, whilst the suspension liquid is passed out of the column. The product is then eluted from the packed bed utilizing standard column-chromatography techniques. The performance of the suspended bed and the agitated contactor operations are demonstrated both by full-scale experimental results and process simulations. The purification of ovalbumin from a hen-egg white feedstock by anion-exchange chromatography was used as a case study in order to prove the concept. With the availability of both pump-packed systems and shear-resistant media, suspended bed chromatography is a better alternative for a range of applications than the traditional batch separations using agitated contactors. PMID:11218119

  15. Bedded salt in Ontario : geology, solution mining and cavern storage

    Energy Technology Data Exchange (ETDEWEB)

    Carter, T. [Ontario Ministry of Natural Resources, London, ON (Canada). Petroleum Resources Centre

    2009-07-01

    This presentation discussed bedded salt geology in Ontario in relation to cavern storage and solution mining. Ontario's salt basin forms part of the Michigan basin. The salt formed as reefs surrounding the shallow basin restricted the flow of water. Salt then formed as the water evaporated. The bedded salt occurs in several layers underlying up to 16,000 km{sup 2} in the province. Subsurface resources used in the area include salt cavern hydrocarbon storage; oil and gas reservoirs; and natural gas reservoir storage. The Salina Group stratigraphy is comprised of several separate salt beds with a maximum combined thickness of 90 m. The Salina salt beds exhibit evidence of dissolution after deposition. There are currently 20 active solution mining wells in operation in the Windsor and Goderich regions. There are currently 112 wells and 70 caverns used for cavern storage in Ontario that are used to store approximately 27 million bbl of liquefied petroleum gas (LPG) and oil. Non-salt layers in the salt beds can interfere with both solution mining and cavern storage operations. tabs., figs.

  16. Bed rest and increased diuretic treatment in chronic congestive heart failure

    DEFF Research Database (Denmark)

    Abildgaard, U; Aldershvile, J; Ring-Larsen, H;

    1985-01-01

    To elucidate the effect of bed rest used as an adjunct to increased diuretic treatment, twelve patients with chronic congestive heart failure (CHF) had a 50% increase in loop diuretic dosage and were allocated to either continuous bed rest or bed rest during nights only. The 24-hour bed rest group...... is a reasonable adjunct to diuretic treatment in patients with CHF....

  17. DESIGN AND APPLICATION OF FLUIDIZED BED PHOTOCATALYTIC REACTOR

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Photocatalytic degradation of organic pollutant is a new and potential method to transform it to harmless inorganic material, such as CO2 and H2O. So far, most of photocatalytic reactors were cylinder or tabulate photoreactor. The relevant photocatalyst was TiO2 nanometer powder. Although a few investigators had aimed their research field to fluidized bed reactor, their reaction systems were of biphase, such as solid-liquid or solid-gas. Few people focused their research on the triphasic fluidized bed photocatalytic reactor[1]. Compared with traditional photoreactors, a triphasic fluidized bed photoreactor has more advantages[2]: (1) The solid photocatalyst can be separated easily. (2) Its configuration meets the requirement of higher surface area-to-volume ratio of photocatalytic, which is much lower in a fixed bed or a plate photoreactor. (3) The UV light can be used more efficiently. (4) The mass transfer conditions can be controlled and improved easily. (5) It suited to pilot-scale or large-scale operations. For the UV light penetration and photon efficiency should be considered, the photocatalytic reactor differed greatly from a typical fluidized bed reactor.

  18. Tanning beds: Impact on health, and recent regulations.

    Science.gov (United States)

    Madigan, Lauren M; Lim, Henry W

    2016-01-01

    As the use of indoor tanning beds gained popularity in the decades after their appearance in the market in the early 1970s, concerns arose regarding their use. Clinical research has revealed an association between indoor tanning and several health risks, including the subsequent occurrence of melanoma and nonmelanoma skin cancers, the development of psychologic dependence, and a tendency toward other high-risk health behaviors. In the face of mounting evidence, legislation has been passed, which includes the restriction of access to tanning beds by minors in 42 states and the District of Columbia, and the recent reclassification by the Food and Drug Administration, which now categorizes tanning beds as class II devices and worthy of restrictions and oversight. Early evidence suggests that these labors are resulting in cultural change, although continued efforts are necessary to limit further exposure and better inform the public of the dangers associated with indoor tanning use. PMID:27638445

  19. Morphological and Physiological Characteristics that Contribute to Insecticide Resistance in Bed Bug (Cimex lectularius L.) Eggs.

    OpenAIRE

    Delong, Brittany E

    2014-01-01

    Although bed bug eggs are a difficult life stage to control with our currently labeled insecticides, few studies have examined how bed bug egg morphology and physiology is potentially related to pesticide resistance in bed bug eggs. Bed bug egg morphological features were examined using scanning electron microscopy (SEM) and the chorion and respiration structures were identified. Scanning electron microscopy photographs and bed bug egg measurements indicated there were no morphological differ...

  20. Potential health impacts of burning coal beds and waste banks

    Science.gov (United States)

    Finkelman, R.B.

    2004-01-01

    Uncontrolled release of pollutants from burning coal beds and waste banks presents potential environmental and human health hazards. On a global scale, the emissions of large volumes of greenhouse gases from burning coal beds may contribute to climate change that alters ecosystems and patterns of disease occurrence. On regional and local scales, the emissions from burning coal beds and waste banks of acidic gases, particulates, organic compounds, and trace elements can contribute to a range of respiratory and other human health problems. Although there are few published reports of health problems caused by these emissions, the potential for problems can be significant. In India, large numbers of people have been displaced from their homes because of health problems caused by emissions from burning coal beds. Volatile elements such as arsenic, fluorine, mercury, and selenium are commonly enriched in coal deposits. Burning coal beds can volatilize these elements, which then can be inhaled, or adsorbed on crops and foods, taken up by livestock or bioaccumulated in birds and fish. Some of these elements can condense on dust particles that can be inhaled or ingested. In addition, selenium, arsenic, lead, tin, bismuth, fluorine, and other elements condense where the hot gaseous emissions come in contact with ambient air, forming mats of concentrated efflorescent minerals on the surface of the ground. These mats can be leached by rainwater and washed into local water bodies providing other potential routes of exposure. Although there are little data linking burning coal beds and waste banks to known health problems, a possibly analogous situation exists in rural China where mineralized coal burned in a residential environment has caused widespread and severe health problems such as fluorosis and arseniasis. ?? 2004 Elsevier B.V. All rights reserved.

  1. Potential health impacts of burning coal beds and waste banks

    Energy Technology Data Exchange (ETDEWEB)

    Finkelman, Robert B. [U.S. Geological Survey, Mail Stop 956 National Center, 12201 Sunrise Valley Drive, Reston, VA 20192 (United States)

    2004-07-12

    Uncontrolled release of pollutants from burning coal beds and waste banks presents potential environmental and human health hazards. On a global scale, the emissions of large volumes of greenhouse gases from burning coal beds may contribute to climate change that alters ecosystems and patterns of disease occurrence. On regional and local scales, the emissions from burning coal beds and waste banks of acidic gases, particulates, organic compounds, and trace elements can contribute to a range of respiratory and other human health problems. Although there are few published reports of health problems caused by these emissions, the potential for problems can be significant. In India, large numbers of people have been displaced from their homes because of health problems caused by emissions from burning coal beds. Volatile elements such as arsenic, fluorine, mercury, and selenium are commonly enriched in coal deposits. Burning coal beds can volatilize these elements, which then can be inhaled, or adsorbed on crops and foods, taken up by livestock or bioaccumulated in birds and fish. Some of these elements can condense on dust particles that can be inhaled or ingested. In addition, selenium, arsenic, lead, tin, bismuth, fluorine, and other elements condense where the hot gaseous emissions come in contact with ambient air, forming mats of concentrated efflorescent minerals on the surface of the ground. These mats can be leached by rainwater and washed into local water bodies providing other potential routes of exposure. Although there are little data linking burning coal beds and waste banks to known health problems, a possibly analogous situation exists in rural China where mineralized coal burned in a residential environment has caused widespread and severe health problems such as fluorosis and arseniasis.

  2. Formation and displacement of bubbles in a packed bed

    CERN Document Server

    Soto, Enrique; Zenit, Roberto

    2010-01-01

    The fluid dynamics video show a gas stream which is injected into a packed bed immersed in water and fluid dynamcis video present the dynamics involved. The refractive index of the water an the packed bed are quite similar and the edges of the spherical particles can be seen. Two distinctive regimens can be observed. The first one, for low air flow rates, which is characterized by the percolation of the air thought the interstitial space among particles. And the second one, for high air flow rates, which is characterized by the accumulation of air inside the packed bed without percolation, it can be observed that the bubble pull apart the particles apart. Furthermore, for the first case the position of the particles remains constant while for the second one a circulation of particles is induced by the bubbles flow.

  3. Modelling of seed drying in fluidised and spouted bed dryers

    OpenAIRE

    Jittanit, W.; Srzednicki, G.; Driscoll, R

    2010-01-01

    Drying experiments were conducted in the fluidised bed dryer (FBD) and spouted bed dryer (SBD) at temperature 40-80°C using maize, rice and wheat seed samples. The experimental data were fitted into four thin-layer drying models by least square method. As a result, Page’s model and two-compartment model were the best-fitted models. Due to the limitation of these models, Page’s model and the twocompartment model were modified by adding the drying temperature term. Subsequently, these models co...

  4. Atmospheric fluidized bed coal combustion research, development and application

    CERN Document Server

    Valk, M

    1994-01-01

    The use of fluidized bed coal combustion technology has been developed in the past decade in The Netherlands with a view to expanding the industrial use of coal as an energy supply. Various research groups from universities, institutes for applied science and from boiler industries participated and contributed to this research area. Comprehensive results of such recent experimentation and development work on atmospheric fluidized bed combustion of coal are covered in this volume. Each chapter, written by an expert, treats one specific subject and gives both the theoretical background as well a

  5. Effect and surfactants on three-phase fluidized bed hydrodynamics

    International Nuclear Information System (INIS)

    Experiments were conducted to discern the relationship between three-phase fluidized bed hydrodynamics and surfactant solution characteristics. The standard characteristic, equilibrium surface tension, is inadequate. A novel method for surface tension evaluation, a dynamic maximum bubble pressure technique, was found to differentiate the 12 different solutions studied. The surfactant solutions were categorized based upon a combination of the terminal bubble rise velocity reduction, the equilibrium surface tension, and the new bubble tension values. These surfactant solution categories were correlated with experimentally observed three-phase fluidized bed and bubble column hydrodynamic behavior. Specifically, empirical correlations for gas holdup are presented

  6. Bacterial counts associated with sawdust and recycled manure bedding treated with commercial conditioners.

    Science.gov (United States)

    Hogan, J S; Bogacz, V L; Thompson, L M; Romig, S; Schoenberger, P S; Weiss, W P; Smith, K L

    1999-08-01

    Bacteria counts associated with untreated organic bedding materials were compared with those of bedding treated with either an alkaline commercial bedding conditioner, acidic commercial bedding conditioner, or hydrated lime. Bedding materials were recycled manure and kiln-dried sawdust. The effects of bedding treatments on bacteria counts differed between bedding types. Each of the bedding treatments significantly reduced bacteria in recycled manure prior to use. The alkaline conditioner and hydrated lime effectively inhibited bacteria in recycled manure for 1 d. Bedding counts and teat swabs of cows housed on recycled manure treated with the alkaline conditioner were reduced on d 2. The use of the acid conditioner in recycled manure had little effect on bacteria in bedding. Sawdust differed from recycled manure in that bacteria in untreated sawdust prior to use were minimal, and populations increased rapidly during the first 2 d after use as bedding. The acid conditioner had a bacteriostatic effect in sawdust, evident by the reduction of bacteria on d 2. The alkaline conditioner and hydrated lime did not alter bacteria counts in sawdust compared with untreated sawdust. Antibacterial activity of each conditioner deteriorated between d 2 and d 6 in both beddings. The antibacterial activities of conditioners were related to the pH of bedding materials. The use of commercial bedding conditioners initially reduced bacterial counts; however, the antibacterial effects had diminished between d 2 and 6 after use in bedding. PMID:10480094

  7. Effectiveness of a Reduced-Risk Insecticide Based Bed Bug Management Program in Low-Income Housing

    Directory of Open Access Journals (Sweden)

    Narinderpal Singh

    2013-11-01

    Full Text Available Bed bug (Cimex lectularius L. infestations are becoming increasingly common in low-income communities. Once they are introduced, elimination is very difficult. As part of the efforts to develop effective and safe bed bug management programs, we conducted a laboratory study evaluating the efficacy of a reduced-risk insecticide—Alpine aerosol (0.5% dinotefuran. We then conducted a field evaluation of a reduced-risk insecticide based integrated pest management (IPM program in low-income family apartments with young children. In laboratory evaluations, direct spray and 5 min exposure to dry Alpine aerosol residue caused 100.0 ± 0.0 and 91.7 ± 8.3% mortality to bed bug nymphs, respectively. Direct Alpine aerosol spray killed 91.3 ± 4.3% of the eggs. The IPM program included education, steam, bagging infested linens, placing intercepting devices under furniture legs and corners of rooms, applying Alpine aerosol and Alpine dust (0.25% dinotefuran, 95% diatomaceous earth dust, and regularly scheduled monitoring and re-treatment. Nine apartments ranging from 1–1,428 (median: 29 bed bugs based on visual inspection and Climbup interceptor counts were included. Over a 6-month period, an average 172 g insecticide (Alpine aerosol + Alpine dust was used in each apartment, a 96% reduction in pesticide usage compared to chemical only treatment reported in a similar environment. The IPM program resulted in an average of 96.8 ± 2.2% reduction in the number of bed bugs. However, elimination of bed bugs was only achieved in three lightly infested apartments (<30 bed bugs at the beginning. Elimination success was closely correlated with the level of bed bug populations.

  8. Nonlinear dynamics and control of a recycle fixed bed reactor

    DEFF Research Database (Denmark)

    Recke, Bodil; Jørgensen, Sten Bay

    1997-01-01

    The purpose of this paper is twofold. Primarily to describe the dynamic behaviour that can be observed in a fixed bed reactor with recycle of unconverted reactant. Secondly to describe the possibilities of model reduction in order to facilitate control design. Reactant recycle has been shown...... to introduce periodic solution to the fixed bed reactor, a phenomenon which is not seen for the system without the recycle, at least not within the Peclet number range investigated in the present work. The possibility of model reduction by the methods of modal decomposition, and by characteristics...

  9. Numerical Simulations of the Effects of a Tidal Turbine Array on Near-Bed Velocity and Local Bed Shear Stress

    Directory of Open Access Journals (Sweden)

    Philip A. Gillibrand

    2016-10-01

    Full Text Available We apply a three-dimensional hydrodynamic model to consider the potential effects of energy extraction by an array of tidal turbines on the ambient near-bed velocity field and local bed shear stress in a coastal channel with strong tidal currents. Local bed shear stress plays a key role in local sediment dynamics. The model solves the Reynold-averaged Navier-Stokes (RANS equations on an unstructured mesh using mixed finite element and finite volume techniques. Tidal turbines are represented through an additional form drag in the momentum balance equation, with the thrust imparted and power generated by the turbines being velocity dependent with appropriate cut-in and cut-out velocities. Arrays of 1, 4 and 57 tidal turbines, each of 1.5 MW capacity, were simulated. Effects due to a single turbine and an array of four turbines were negligible. The main effect of the array of 57 turbines was to cause a shift in position of the jet through the tidal channel, as the flow was diverted around the tidal array. The net effect of this shift was to increase near-bed velocities and bed shear stress along the northern perimeter of the array by up to 0.8 m·s−1 and 5 Pa respectively. Within the array and directly downstream, near-bed velocities and bed shear stress were reduced by similar amounts. Changes of this magnitude have the potential to modify the known sand and shell banks in the region. Continued monitoring of the sediment distributions in the region will provide a valuable dataset on the impacts of tidal energy extraction on local sediment dynamics. Finally, the mean power generated per turbine is shown to decrease as the turbine array increased in size.

  10. 42 CFR 409.22 - Bed and board.

    Science.gov (United States)

    2010-10-01

    ... CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM HOSPITAL INSURANCE BENEFITS Posthospital SNF Care § 409.22 Bed and board. (a) Semiprivate and ward accommodations. Except for applicable deductible and coinsurance amounts Medicare Part A pays in full...

  11. Measurement and modeling of bed shear stress under solitary waves

    Digital Repository Service at National Institute of Oceanography (India)

    Jayakumar, S.; Guard, P.A.; Baldock, T.E.

    ) < ~ 10 sup (5)). Measurements were carried out where the wave height to water depth (h/d) ratio varied between 0.12 and 0.68; maximum near bed velocity varied between 0.16 m/s and 0.51 m/s and the maximum total shear stress (sum of skin shear stress...

  12. ASSESSING STREAM BED STABILITY AND EXCESS SEDIMENTATION IN MOUNTAIN STREAMS

    Science.gov (United States)

    Land use and resource exploitation in headwaters catchments?such as logging, mining, and road building?often increase sediment supply to streams, potentially causing excess sedimentation. Decreases in mean substrate size and increases in fine stream bed sediments can lead to inc...

  13. Fluid Bed Technology: Overview and Parameters for Process Selection

    Directory of Open Access Journals (Sweden)

    Saurabh Srivastava

    2010-10-01

    Full Text Available Formulation development is the most emerging and upcoming face of pharmaceutical technology in the current era. It is contemporarily capturing the market leaps and bounds with recent trends and developments with its innovative techniques. The day-to-day advancements in the research have provided an edge to this brilliant branch of pharmaceutical sector for not only uplifting the pharmacy profession but also to conquer the diseased state for nurturing the health and humanity. The fluid-bed technology or air-suspension process is the potential tool to develop newer trends and implications in the sector of formulation development with maximum therapeutic efficacy. The technology is used for granulation/agglomeration, layering and coating of a wide range of particle size. In addition; the technique can be used for the drying process as well. The three patterns of the fluid-bed processes could be characterized by the position/location of the spray nozzle i.e. top spray, bottom spray or tangential spray. This article reviews the three techniques with some innovative fluid bed pelletizing technologies like CPS™, MicroPx™, ProCell™ and discusses their applications, advantages and limitations. These advanced pelletizing technologies are recentely added to complement the actual capabilities of standard fluid bed processing for development of various dosage forms of “Multiple Unit Particulate Systems” (MUPS with better therapeutic efficacy and economic benefits.

  14. Model for boiling and dryout in particle beds

    International Nuclear Information System (INIS)

    Over the last ten years experiments and modeling of dryout in particle beds have produced over fifty papers. Considering only volume-heated beds, over 250 dryout measurements have been made, and are listed in this work. In addition, fifteen models to predict dryout have been produced and are discussed. A model is developed in this report for one-dimensional boiling and dryout in a porous medium. It is based on conservation laws for mass, momentum, and energy. The initial coupled differential equations are reduced to a single first-order differential equation with an algebraic equation for the upper boundary condition. The model includes the effects of both laminar and turbulent flow, two-phase friction, and capillary force. The boundary condition at the bed bottom includes the possibility of inflowing liquid and either an adiabatic or a bottom-cooled support structure. The top of the bed may be either channeled or subcooled. In the first case the channel length and the saturation at the base of the channels are predicted. In the latter case, a criterion for penetration of the subcooled zone by channels is obtained

  15. Status and threats on seagrass beds using GIS in Vietnam

    Science.gov (United States)

    Luong, Cao Van; Thao, Nguyen Van; Komatsu, Teruhisa; Ve, Nguyen Dac; Tien, Dam Duc

    2012-10-01

    Seagrasses, marine flowering plants, are widely distributed along temperate and tropical coastlines of the world. Seagrasses have key ecological roles in coastal ecosystems and can form extensive meadows supporting high biodiversity. Till now, fourteen seagrass species belonging to four families were found in Vietnam: Halophila beccarii, H. decipiens, H. ovalis, H. minor, Thalassia hemprichii, Enhalus acoroides, Ruppia maritima, Halodule pinifolia, H. uninervis, Syringodium isoetifolium, Cymadocea rotundata, C. serrulata and Thalassodendron ciliatum. A total area of seagrass beds in Vietnam is estimated to be approximately 17000 ha by satellite images and GIS technology. In recent years, the distribution areas and densities of seagrass beds in Vietnam have been serious decreased compared with those 10-15 years ago. The decline level depended on the impacts by the natural process, the economical activities and the conservation awareness of local people. Thus, it is different at each coastal area. Generally speaking, the distribution areas and densities of seagrass beds were decreased by more than 50%. Seagrasses on tidal flats in some areas such as Quang Ninh, Hai Phong, Phu Quoc seem to be nearly lost. The distribution areas of seagrass beds in 2009 at Tam Giang-Cau Hai lagoon and Cua Dai estuary was decreased by 50-70% of those in early 1990s.

  16. Effect of impulse and bedding on impact toughness of coal

    Institute of Scientific and Technical Information of China (English)

    YU Yong-jiang; WANG Lai-gui; LI Jian-xin

    2008-01-01

    In order to understand the properties of impact toughness of coal at different impact speeds,and the change of impact toughness of lump coal to joint directivity of lump coal,a series of impact tests were conducted on Beijing Da'anshan Lump Coal at different impact speeds and in different impact direction.Through analyzing the test result,it is shown that the change of testing samples is similar when impact is exerted on the vertical bedding and the parallel bedding when the impulse is less than 20 Nos,and the difference increases with the impulse increasing when the impulse is more than 20 Nos.At the same time,the expanding energy of fracture in samples increases with its expanding speed,and the expanding energy of fracture has close relation with the impact direction of the tested samples.And the difference of impact toughness of lump coal produced by different impact direction increase with the impact speed.The fracture surface of lump coal when impact is exerted on the vertical bedding is smooth and the broken block number is fewer;but the fracture surface of lump coal when impact is exerted on the parallel bedding isn't smooth and the broken block number is more,which inflects impact toughness of coal is sensitive to some deficiency.

  17. Effect of impulse and bedding on impact toughness of coal

    Institute of Scientific and Technical Information of China (English)

    YU Yong-jiang; WANG Lai-gui; LI Jian-xin

    2008-01-01

    In order to understand the properties of impact toughness of coal at different impact speeds, and the change of impact toughness of lump coal to joint directivity of lump coal, a series of impact tests were conducted on Beijing Da'anshan Lump Coal at different impact speeds and in different impact direction. Through analyzing the test result, it is shown that the change of testing samples is similar when impact is exerted on the vertical bedding and the parallel bedding when the impulse is less than 20 Nos, and the difference increases with the impulse increasing when the impulse is more than 20 Nos. At the same time, the expanding energy of fracture in samples increases with its expanding speed, and the expanding energy of fracture has close relation with the impact direction of the tested samples. And the difference of impact toughness of lump coal produced by different im-pact direction increase with the impact speed. The fracture surface of lump coal when im-pact is exerted on the vertical bedding is smooth and the broken block number is fewer; but the fracture surface of lump coal when impact is exerted on the parallel bedding isn't smooth and the broken block number is more, which inflects impact toughness of coal is sensitive to some deficiency.

  18. Developing and evaluating a meeting assistant test bed

    NARCIS (Netherlands)

    Post, W.M.; Lincoln, M.

    2008-01-01

    A test bed has been developed in which participants are tasked to work in simulated, scenario based, projects in which face-to-face and remote meetings of about 45 minutes have to be held. Measures on performance, team factors and remote aspects are automatically collected with electronic questionna

  19. Stratum energy of coal-bed gas reservoir and their control on the coal-bed gas reservoir formation

    Institute of Scientific and Technical Information of China (English)

    WU; CaiFang; QIN; Yong; FU; XueHai

    2007-01-01

    Stratum energy of coal-bed gas reservoir, including coal-radix flexibility energy, groundwater flexibility energy and gas flexibility energy (hereinafter "three energy"), depends on the energy homeostasis system, the core process of which is the effective transfer of energy and the geological selective process. Combining with the mechanics experimentations of coal samples, different flexibility energy has been analyzed and researched quantificationally, and a profound discussion to their controls on the coal-bed gas reservoir formation has been made. It is shown that when gas reservoir is surrounded by edge water and bottom water, the deposited energy in the early phase of forming gas reservoir is mostly coal-radix and gas flexibility energy, but the effect of groundwater flexibility energy increases while water-body increases. The deposited energy in the middle and later phase of forming gas reservoir is mostly gas flexibility energy, which is greater than 80% of all deposited energy. In the whole process, larger groundwater body exerts greater influences on gas accumulation. The paper indicated that higher stratum energy is more propitious to forming coal-bed gas reservoir. And higher coal-radix flexibility energy and gas flexibility energy are more propitious to higher yield of gas reservoirs, while higher groundwater flexibility energy is more propitious to stable yield of gas reservoirs. Therefore, the key to evaluating the coal-bed gas reservoir formation is the stratum energy of coal-bed gas reservoir.

  20. Packed bed heat storage: Continuum mechanics model and validation

    Science.gov (United States)

    Knödler, Philipp; Dreißigacker, Volker; Zunft, Stefan

    2016-05-01

    Thermal energy storage (TES) systems are key elements for various types of new power plant concepts. As possible cost-effective storage inventory option, packed beds of miscellaneous material come into consideration. However, high technical risks arise due to thermal expansion and shrinking of the packed bed's particles during cyclic thermal operation, possibly leading to material failure. Therefore, suitable tools for designing the heat storage system are mandatory. While particle discrete models offer detailed simulation results, the computing time for large scale applications is inefficient. In contrast, continuous models offer time-efficient simulation results but are in need of effective packed bed parameters. This work focuses on providing insight into some basic methods and tools on how to obtain such parameters and on how they are implemented into a continuum model. In this context, a particle discrete model as well as a test rig for carrying out uniaxial compression tests (UCT) is introduced. Performing of experimental validation tests indicate good agreement with simulated UCT results. In this process, effective parameters required for a continuous packed bed model were identified and used for continuum simulation. This approach is validated by comparing the simulated results with experimental data from another test rig. The presented method significantly simplifies subsequent design studies.

  1. Cold tolerance of bed bugs and practical recommendations for control.

    Science.gov (United States)

    Olson, Joelle F; Eaton, Marc; Kells, Stephen A; Morin, Victor; Wang, Changlu

    2013-12-01

    Bed bugs were exposed to freezing temperatures for various exposure times to determine cold tolerance and mortality estimates for multiple life stages. The mean supercooling point for all bed bug life stages ranged from -21.3 degrees C to -30.3 degrees C, with the egg stage reporting the lowest value. A probit analysis provided a lower lethal temperature (LLT99) of -31.2 degrees C when estimates from all life stages were combined, demonstrating that all stages of bed bugs are not capable of surviving temperatures below body freezing and are therefore freeze intolerant. At conditions above the LLT99, bed bug mortality depended on temperature and exposure time at temperatures above LLT99. Based on our model estimates, survival was estimated for temperatures above -12 degrees C even after 1 wk of continuous exposure. However, exposure to temperatures below -13 degrees C will result in 100% mortality in d to ensure mortality of all life stages. Unfortunately, sublethal exposure to lower temperatures did not prevent subsequent feeding behavior in surviving stages. Practical recommendations for management of potentially infested items are discussed. PMID:24498745

  2. Modelling of thermal and mechanical behaviour of pebble beds

    International Nuclear Information System (INIS)

    FZK (Forshungzentrum Karlsruhe) is developing a Helium Cooled Pebble Bed (HCPB) Blanket Concept for fusion power reactors based on the use of ceramic breeder materials and beryllium multiplier in the form of pebble beds. The design of such a blanket requires models and computer codes describing the thermal-mechanical behavior of pebble beds to evaluate the temperatures, stresses, deformations and mechanical interactions between pebble beds and the structure with required accuracy and reliability. The objective to describe the beginning of life condition for the HCPB blanket seems near to be reached. Mechanical models that describe the thermo-mechanical behavior of granular materials used in form of pebble beds are implemented in a commercial structure code. These models have been calibrated using the results of a large series of dedicated experiments. The modeling work is practically concluded for ceramic breeder; it will be carried on in the next year for beryllium to obtain the required correlations for creep and the thermal conductivity. The difficulties for application in large components (such as the HCPB blanket) are the limitations of the present commercial codes to manage such a set of constitutive equations under complex load conditions and large mesh number. The further objective is to model the thermal cycles during operation; the present correlations have to be adapted for the release phase. A complete description of the blanket behavior during irradiation is at the present out of our capability; this objective requires an extensive R and D program that at the present is only at the beginning. (Y.Tanaka)

  3. Exercise thermoregulation with bed rest, confinement, and immersion deconditioning

    Science.gov (United States)

    Greenleaf, J. E.

    1997-01-01

    Altered thermoregulation following exposure to prolonged (12-14 days) of bed rest and 6 hr of head-down thermoneutral water immersion in humans, and cage confinement (8 weeks) in male, mongrel dogs resulted in occasional increased core temperature (Tcore) at rest, but consistent "excessive" increase in Tcore during submaximal exercise. This excessive increase in Tcore in nonexercising and exercising subjects was independent of the mode (isometric or isotonic) of exercise training during bed rest, and was associated with the consistent hypovolemia in men but not in women taking estrogen supplementation (1.25 mg premarin/ day) which restored plasma volume during bed rest to ambulatory control levels. Post-bed rest exercise sweating (evaporative heat loss) was unchanged or higher than control levels; however, calculated tissue heat conductance was significantly lower in men, and forearm venoconstriction was greater (venous volume was reduced) in women during exercise after bed rest. Because sweating appeared proportional to the increased level of Tcore, these findings suggest that one major factor for the excessive hyperthermia is decreased core to periphery heat conduction. Exercising dogs respond like humans with excessive increase in both rectal (Tre) and exercising muscle temperatures (Tmu) after confinement and, after eight weeks of exercise training on a treadmill following confinement, they had an attenuated rate of increase of Tre even below ambulatory control levels. Intravenous infusion of glucose also attenuated not only the rise in Tre during exercise in normal dogs, but also the excessive rise in Tre and exercising Tmu after confinement. Oral glucose also appeared to reduce the rate of increase in excessive Tre in men after immersion deconditioning. There was a greater rate of rise in Tcore in two cosmonauts during supine submaximal exercise (65% VO2 max) on the fifth recovery day after the 115-day Mir 18 mission. Thus, the excessive rise in core

  4. Investigation of debris bed formation, spreading and coolability

    Energy Technology Data Exchange (ETDEWEB)

    Kudinov, P.; Konovalenko, A.; Grishchenko, D.; Yakush, S.; Basso, S.; Lubchenko, N.; Karbojian, A. [Royal Institute of Technology, KTH. Div. of Nuclear Power Safety, Stockholm (Sweden)

    2013-08-15

    The work is motivated by the severe accident management strategy adopted in Nordic type BWRs. It is assumed that core melt ejected from the vessel will fragment, quench and form a coolable debris bed in a deep water pool below the vessel. In this work we consider phenomena relevant to the debris bed formation and coolability. Several DEFOR-A (Debris Bed Formation - Agglomeration) tests have been carried out with new corium melt material and a melt releasing nozzle mockup. The influence of the melt material, melt superheat, jet free fall height on the (i) faction of agglomerated debris, (ii) particle size distribution, (iii) ablation/plugging of the nozzle mockup has been addressed. Results of the DECOSIM (Debris Coolability Simulator) code validation against available COOLOCE data are presented in the report. The dependence of DHF on system pressure from COOLOCE experiments can be reproduced quite accurately if either the effective particle diameter or debris bed porosity is increased. For a cylindrical debris bed, good agreement is achieved in DECOSIM simulations for the particle diameter 0.89 mm and porosity 0.4. The results obtained are consistent with MEWA simulation where larger particle diameters and porosities were found to be necessary to reproduce the experimental data on DHF. It is instructive to note that results of DHF prediction are in better agreement with POMECO-HT data obtained for the same particles. It is concluded that further clarification of the discrepancies between different experiments and model predictions. In total 13 exploratory tests were carried out in PDS (particulate debris spreading) facility to clarify potential influence of the COOLOCE (VTT) facility heaters and TCs on particle self-leveling process. Results of the preliminary analysis suggest that there is no significant influence of the pins on self-leveling, at least for the air superficial velocities ranging from 0.17 up to 0.52 m/s. Further confirmatory tests might be needed

  5. Exploring Parental Bonding in BED and Non-BED Obesity Compared with Healthy Controls: Clinical, Personality and Psychopathology Correlates.

    Science.gov (United States)

    Amianto, Federico; Ercole, Roberta; Abbate Daga, Giovanni; Fassino, Secondo

    2016-05-01

    Early inadequate attachment experiences are relevant co-factors in the development of obesity and Binge Eating Disorder (BED), which often concurs with obesity. The relationship of parental bonding with personality and psychopathology may influence treatment strategies for obese subjects, either affected or not with BED. In this study, 443 obese women (BMI ≥ 30 kg/m(2)), including 243 with and 200 without BED, and 158 female controls were assessed with regards to attachment, personality and eating psychopathology measures. Clusters obtained using the scores of the Parental Bonding Instrument (PBI) were compared with each other and with a control subjects' group. Lower scores of parental bonding distinguished obese subjects with respect to healthy controls. The cluster analysis revealed two clusters of parenting among obese subjects. The larger one displayed intermediate care and overprotection between controls and the smaller cluster, with the exception of paternal overprotection which is similar to controls. This larger cluster was characterized by low persistence and levels of psychopathology which are intermediate between healthy controls and the smaller cluster. The smaller cluster displayed lower care and higher overcontrol from both parents. It also displays more extreme personality traits (high novelty seeking and harm avoidance, and lower self-directedness and cooperativeness) and more severe eating and general psychopathology. Different parenting dynamics relate to different personality patterns and eating psychopathology of obese subjects, but not to binge eating conducts. Personality differences between parenting clusters are more extensive than those between BED and non-BED subgroups. The two different typologies of obese subjects based on parenting may be relevant for treatment personalization.

  6. Experimental determination of bed agglomeration tendencies of some common agricultural residues in fluidized bed combustion and gasification

    Energy Technology Data Exchange (ETDEWEB)

    Natarajan, E.; Rao, A.N. [Anna University, Madras (India). Centre for New and Renewable Sources of Energy; Ohman, M.; Nordin, A. [Umea University (Sweden). Energy Technology Centre; Gabra, M. [Lulea University of Technology (Sweden). Div. of Energy Engineering; Liliedahl, T. [Royal Institute of Technology, Stockholm (Sweden). Dept. of Chemical Engineering and Technology

    1998-12-31

    Ever increasing energy demand and the polluting nature of existing fossil fuel energy sources demonstrate the need for other non-polluting and renewable sources of energy. The agricultural residues available in abundance in many countries can be used for power generation. The fluidized bed technology seems to be suitable for converting a wide range of agricultural residues into energy, due to its inherent advantages of fuel flexibility, low operating temperature and isothermal operating condition. The major ash-related problem encountered in fluidized beds is agglomeration which, in the worst case, may result in total defluidization and unscheduled downtime. The initial agglomeration temperature for some common tropical agricultural residues were experimentally determined by using a newly developed method based on the controlled fluidized bed agglomeration test. The agricultural residues chosen for the study were rice husk, bagasse, cane trash and olive flesh. The results showed that the initial agglomeration temperatures were less than the initial deformation temperature predicted by the ASTM standard ash fusion tests for all fuels considered. The initial agglomeration temperatures of rice husk and bagasse were more than 1000{sup o}C. The agglomeration of cane trash and olive flesh was encountered at relatively low temperatures and their initial agglomeration temperatures in gasification were lower than those in combustion with both bed materials. The use of lime as bed material instead of quartz improved the agglomeration temperature of cane trash and olive flesh in combustion and decreased the same in gasification. The results indicate that rice husk and bagasse can be used in the fluidized bed for energy generation since their agglomeration temperatures are sufficiently high. (author)

  7. EFFECT OF VERTICAL BAFFLES ON PARTICLE MIXING AND DRYING IN FLUIDIZED BEDS OF GROUP D PARTICLES

    Institute of Scientific and Technical Information of China (English)

    Chung Lim Law; Siti Masrinda Tasirin; Wan Ramli Wan Daud; Derek Geldart

    2003-01-01

    This study reports the effect of vertical baffles on the group D powder mixing and drying characteristics in a batch fluidized bed dryer. Results obtained in this study showed that operating the fluidized bed dryer with vertical baffles gave better particle mixing. This is due to the fact that the vertical baffles acted to limit the growth of small bubbles into large bubbles and the small bubbles caused more vigorous mixing in the bed of particles before finally erupting at the bed surface. Thus, insertion of vertical baffles is a useful way to process group D particles in a fluidized bed, especially when the fluidized bed is large.

  8. Characterization of the extremely arsenic-resistant Brevibacterium linens strain AE038-8 isolated from contaminated groundwater in Tucumán, Argentina

    Science.gov (United States)

    Maizel, Daniela; Blum, Jodi S.; Ferrero, Marcela A.; Utturkar, Sagar M.; Brown, Steven D.; Rosen, Barry P.; Oremland, Ronald S.

    2015-01-01

    Brevibacterium linens AE038-8, isolated from As-contaminated groundwater in Tucumán (Argentina), is highly resistant to arsenic oxyanions, being able to tolerate up to 1 M As(V) and 75 mM As(III) in a complex medium. Strain AE038-8 was also able to reduce As(V) to As(III) when grown in complex medium but paradoxically it could not do this in a defined minimal medium with sodium acetate and ammonium sulfate as carbon and nitrogen sources, respectively. No oxidation of As(III) to As(V) was observed under any conditions. Three copies of the ars operon comprising arsenic resistance genes were found on B. linens AE038-8 genome. In addition to the well known arsC, ACR3 andarsR, two copies of the arsO gene of unknown function were detected.

  9. Sleeping arrangements and mass distribution of bed nets in six districts in central and northern Mozambique

    OpenAIRE

    Plucinski, M. M.; Chicuecue, S.; Macete, E.; Chambe, G. A.; Muguande, O.; Matsinhe, G.; Colborn, J.; Yoon, S. S.; Doyle, T J; Kachur, S. P.; Aide, P; Alonso, P. L.; Guinovart, C.; Morgan, J.

    2015-01-01

    OBJECTIVE: Universal coverage with insecticide-treated bed nets is a cornerstone of modern malaria control. Mozambique has developed a novel bed net allocation strategy, where the number of bed nets allocated per household is calculated on the basis of household composition and assumptions about who sleeps with whom. We set out to evaluate the performance of the novel allocation s...

  10. Bed bugs and possible transmission of human pathogens: a systematic review.

    Science.gov (United States)

    Lai, Olivia; Ho, Derek; Glick, Sharon; Jagdeo, Jared

    2016-10-01

    The global population of bed bugs (Cimex lectularius and Cimex hemipterus, family Cimicidae) has undergone a significant resurgence since the late 1990s. This is likely due to an increase in global travel, trade, and the number of insecticide-resistant bed bugs. The global bed bug population is estimated to be increasing by 100-500 % annually. The worldwide spread of bed bugs is concerning, because they are a significant socioeconomic burden and a major concern to public health. According to the United States Environmental Protection Agency, bed bugs are "a pest of significant health importance." Additionally, 68 % of U.S. pest professionals reported that bed bugs are the most challenging pest to treat. Upwards of 45 disease pathogens have been reported in bed bugs. Recent studies report that bed bugs may be competent vectors for pathogens, such as Bartonella quintana and Trypanosoma cruzi. However, public health reports have thus far failed to produce evidence that major infectious disease outbreaks have been associated with bed bugs. Since many disease pathogens have previously been reported in bed bugs and the worldwide bed bug population is now drastically increasing, it stands to reason to wonder if bed bugs might transmit human pathogens. This review includes a literature search on recently published clinical and laboratory studies (1990-2016) investigating bed bugs as potential vectors of infectious disease, and reports the significant findings and limitations of the reviewed studies. To date, no published study has demonstrated a causal relationship between bed bugs and infectious disease transmission in humans. Also, we present and propose to expand on previous hypotheses as to why bed bugs do not transmit human pathogens. Bed bugs may contain "neutralizing factors" that attenuate pathogen virulence and, thereby, decrease the ability of bed bugs to transmit infectious disease. PMID:27295087

  11. Woody waste air gasification in fluidized bed with Ca- and Mg-modified bed materials and additives

    International Nuclear Information System (INIS)

    This study focuses on the promotion of biomass gasification for hydrogen production in a fluidized bed reactor with the bed additives zeolite, CaO, and Ca- and Mg-based silica sands. The results show that zeolite has higher capacity for enhancing hydrogen promotion abilities than CaO with the amount was 200 g in tests. Regarding the Ca- and Mg-based silica sands, Ca/SiO2 decreases the CO2 selectivity and Mg/SiO2 enhances the H2 selectivity owing to CO2 adsorption via the formation of CaO and the promotion of the water gas shift reaction, respectively. The optimal concentration of Mg-based bed materials corresponds to a Mg concentration of 0.5 wt.%. The additives play important roles in increasing the reaction rate, enhancing the biomass gasification, and promoting carbon transformation. -- Graphical abstract: The aim of this study is not only in estimation of the influence of the alkaline metals concentrations, but also in preparation of the modified fluidization mediums. A basic stoichiometric analysis of alkaline concentration for hydrogen production during biomass gasification in fluidized bed is also in consideration. Highlights: ► Various bed-additives concentrations on syngas performance are discussed. ► All additives significantly increase rate of hydrogen production in gasification. ► Zeolite has higher capacity for enhancing hydrogen production rate than CaO. ► Ca-based additives promoted the heating value and cold gas efficiency. ► The optimal concentration of Mg-based additive was 0.5 wt.% for hydrogen production

  12. Emissions from multiple-spouted and spout-fluid fluidized beds using rice husks as fuel

    Energy Technology Data Exchange (ETDEWEB)

    Albina, D.O. [School of Engineering and Architecture, Mindanao Polytechnic State College, Cagayan de Oro City 9000 (Philippines)

    2006-10-15

    This paper presents the experimental results of the emissions of CO and CO{sub 2} using rice husks as fuel on different configurations of spout-fluidized beds namely, multiple-spouted and spout-fluid fluidized bed. The emission of pollutants from the multiple-spouted bed and spout-fluid bed was investigated with rice husk fuel. The operating parameters considered were the different levels of excess air, different primary-to-secondary air ratios at each level of excess air and method of feeding. It was found that emission of CO from the multiple-spouted bed seemed to be lower with under-bed feeding of the rice husk fuel compared to over-bed feeding. However, the emission of CO{sub 2} did not change significantly for both methods of feeding. Changes in excess air levels influenced the emissions of CO and CO{sub 2} from the multiple-spouted bed within the excess air range investigated. It was found that emission of CO was less at 10% excess air with over-bed feeding; emission of CO in the case of under-bed feeding was lowest at 20% excess air level. It was found that the method of feeding had not significantly influenced the emission of CO and CO{sub 2} in the spout-fluid bed. The combustion efficiency however, in general, was slightly higher in the case of under-bed feeding compared to over-bed feeding. Emission of CO was less in the spout-fluid bed compared with the emission of CO in the multiple-spouted bed. The result can be likely attributed to the higher combustion efficiency attained by the spout-fluid bed compared with that of multiple-spouted bed. (author)

  13. Modeling and field observations of char bed processes in black liquor recovery boilers

    Energy Technology Data Exchange (ETDEWEB)

    Engblom, M.

    2010-07-01

    The char bed plays an important role in kraft black liquor combustion. Stable operation of the char bed promotes efficient and safe operation of the black liquor recovery boiler. It also plays a crucial role in the recovery of the pulping chemicals. Char bed operation involves controlling the char bed size and shape. Mathematical modeling based on computational fluid dynamics (CFD) haas been applied to recovery boilers for increased insights into the recovery furnace processes and to aid in the design of new boilers. So far, all CED-based char bed models reported in literature have used a fixed bed shape. This imposes restrictions on simulation of char bed burning by not considering inherently occurring changes in bed shape. In this thesis, a CED -based recovery furnace model is further developed to predict changes in bed shape. The new model is used in simulation of existing recovery boilers. The predictions of bed shape are compared with observations from real boilers. The furnace model is capable of correctly simulating the overall response of the char bed size to operational changes. This confirms the current quantitative overall understanding of char bed burning. In addition to modeling, visual observations of the char bed processes were made in this work. The observations provide validation data concerning the physical behavior of the char bed, and the findings from the observations can be used in further development of char bed models. Modeling and simulations of fundamental laboratory scale char bed experiments reported in literature are also carried out. The simulations complement the experimental data by providing detailed insights into gas phase reactions that can occur inside the gas boundary layer above a char bed. (orig.)

  14. Fluidized and vibrofluidized shallow beds of fresh leaves

    Institute of Scientific and Technical Information of China (English)

    Renata de Aquino Brito Lima; Maria do Carmo Ferreira

    2011-01-01

    The fluid dynamics behavior of shallow fluidized and vibrofluidized beds operating with fresh leaves was investigated with the aim of exploring drying applications in a modified conveyor belt (MCB) system, which may be operated in a fixed- or fiuidized-bed mode. Leaves of the specimens Duranta repens,Schinus molle, Coleus barbatus, Buxus sempervirens, and Bougainvillea spectabilis were tested with a range of sphericities from 0.063 to 0.213. bulk densities from 0.038 to 0.251 g/cm3. apparent densities from 0.52 to 0.97 g/cm3 and ratios of total surface area to volume from 21 to 224 cm-t. Fluidization characteristic curves were obtained by measuring pressure drops versus air velocity in a rectangular column of 0.20m x 0.11 m cross section. It was not possible to reach real fluidized regimes with the leaves due to strongly non-homogeneous beds. Nevertheless, the characteristic curves allowed for the identification of a transition regime from fixed- to expanded-beds, and parameters such as air velocity and pressure drop obtained from the experimental data at the transition were reproducible for specimens with lower surface area or lower specific gravity (i.e., Duranta repens, Schinus molle, and Bougainvillea spectabilis).The transition velocity and pressure drop could not be predicted by the literature developed for estimat0.5 and 1.0 helped to reduce channeling and decrease the transition velocities from fixed to expanded regimes although it did not affect the pressure drops after the bed expansion. The results suggest that drying fresh leaves using the MCB dryer operating in a fluidized mode would not be feasible because none of the materials investigated attained a high-quality fluidization. Operation of the MCB dryer may be possible by alternating between the fixed and vibrofluidized modes. For the specimens tested, the drying should be performed in a range of air velocities from 0.50 to 0.60 m/s to ensure that the operation is in a vibrofluidized regime. The

  15. Application of ultrasonic backscattering for level measurement and process monitoring of expanded-bed adsorption columns.

    Science.gov (United States)

    Thelen, T V; Mairal, A P; Thorsen, C S; Ramirez, W F

    1997-01-01

    Expanded-bed adsorption is a newly commercialized technique for the purification of proteins from cellular debris in downstream processing. An expanded bed presents the possibility of protein recovery in a single step, eliminating the often costly clarification processing steps such as ultrafiltration, centrifugation, and precipitation. A major obstacle to the successful commercialization of this technology is the inability to accurately monitor and control the bed height in these systems. Fluctuations in the feedstock viscosity are common during normal operation and tend to make the operation and control of expanded beds for biological applications complex and difficult. We develop a level measurement technique based upon ultrasonics. It is shown that this technique has great promise for bed-height measurement in expanded-bed adsorption systems. Furthermore, the bed-height measurement can be used in feedback control strategies for bed-height regulation. The proposed ultrasonic sensor is also capable of monitoring for plugging and bubbling in the column. PMID:9336988

  16. Dissolved organic carbon fluxes by seagrass meadows and macroalgal beds

    OpenAIRE

    Barrón, Cristina; Apostolaki, Eugenia T.; Duarte, Carlos M.

    2014-01-01

    Estimates of dissolved organic carbon (DOC) release by marine macrophyte communities (seagrass meadows and macroalgal beds) based on in situ benthic chambers from published and unpublished are compiled in this study. The effect of temperature and light availability on DOC release by macrophyte communities was examined. Almost 85% of the seagrass communities and all of macroalgal communities examined acted as net sources of DOC. Net DOC fluxes in seagrass communities increase positively with w...

  17. Study of Solids and Gas Distribution in Spouted Bed Operated In Stable and Unstable Conditions

    OpenAIRE

    G. M. Alwan; Aradhya, S.B

    2014-01-01

    A spouted bed is a special case of fluidization. It is an effective means of contacting gas with coarse solid particles. Spouted beds should be designed and operated to overcome performance instability and improves the uniform distribution of particles. Steady-state measurements were carried out in the 0.152 m ID cylindrical spouted bed made of Plexiglas that used 60° conical shape spout-air bed. The evaluation of solid and gas holdup in the two regions of spouted bed at stabl...

  18. Thermal modeling of microwave heated packed and fluidized bed catalytic reactors.

    Science.gov (United States)

    Thomas, J R; Faucher, F

    2000-01-01

    Thermal models of small-scale, microwave-heated, packed-bed and fluidized-bed catalytic chemical reactors were developed to investigate the possibility of selectively heating the catalyst sites or the catalyst pellets with microwaves. Results indicate catalyst sites may be selectively heated under special conditions in a packed or fluidized bed, and catalyst pellets may be heated above the temperature of the cooling(and reacting) gas under certain conditions in a fluidized bed. PMID:11098441

  19. Role of vision and mechanoreception in bed bug, Cimex lectularius L. behavior.

    Directory of Open Access Journals (Sweden)

    Narinderpal Singh

    Full Text Available The role of olfactory cues such as carbon dioxide, pheromones, and kairomones in bed bug, Cimex lectularius L. behavior has been demonstrated. However, the role of vision and mechanoreception in bed bug behavior is poorly understood. We investigated bed bug vision by determining their responses to different colors, vertical objects, and their ability to detect colors and vertical objects under low and complete dark conditions. Results show black and red paper harborages are preferred compared to yellow, green, blue, and white harborages. A bed bug trapping device with a black or red exterior surface was significantly more attractive to bed bugs than that with a white exterior surface. Bed bugs exhibited strong orientation behavior toward vertical objects. The height (15 vs. 30 cm tall and color (brown vs. black of the vertical object had no significant effect on orientation behavior of bed bugs. Bed bugs could differentiate color and detect vertical objects at very low background light conditions, but not in complete darkness. Bed bug preference to different substrate textures (mechanoreception was also explored. Bed bugs preferred dyed tape compared to painted tape, textured painted plastic, and felt. These results revealed that substrate color, presence of vertical objects, and substrate texture affect host-seeking and harborage-searching behavior of bed bugs. Bed bugs may use a combination of vision, mechanoreception, and chemoreception to locate hosts and seek harborages.

  20. Role of vision and mechanoreception in bed bug, Cimex lectularius L. behavior.

    Science.gov (United States)

    Singh, Narinderpal; Wang, Changlu; Cooper, Richard

    2015-01-01

    The role of olfactory cues such as carbon dioxide, pheromones, and kairomones in bed bug, Cimex lectularius L. behavior has been demonstrated. However, the role of vision and mechanoreception in bed bug behavior is poorly understood. We investigated bed bug vision by determining their responses to different colors, vertical objects, and their ability to detect colors and vertical objects under low and complete dark conditions. Results show black and red paper harborages are preferred compared to yellow, green, blue, and white harborages. A bed bug trapping device with a black or red exterior surface was significantly more attractive to bed bugs than that with a white exterior surface. Bed bugs exhibited strong orientation behavior toward vertical objects. The height (15 vs. 30 cm tall) and color (brown vs. black) of the vertical object had no significant effect on orientation behavior of bed bugs. Bed bugs could differentiate color and detect vertical objects at very low background light conditions, but not in complete darkness. Bed bug preference to different substrate textures (mechanoreception) was also explored. Bed bugs preferred dyed tape compared to painted tape, textured painted plastic, and felt. These results revealed that substrate color, presence of vertical objects, and substrate texture affect host-seeking and harborage-searching behavior of bed bugs. Bed bugs may use a combination of vision, mechanoreception, and chemoreception to locate hosts and seek harborages. PMID:25748041

  1. Cyclic Sediment Trading Between Channel and River Bed Sediments

    Science.gov (United States)

    Haddadchi, A.

    2015-12-01

    Much of the previous work on sediment tracing has focused on determining either the initial sources of the sediment (soils derive from a particular rock type) or the erosion processes generating the sediment. However, alluvial stores can be both a source and sink for sediment transported by streams. Here geochemical and fallout radionuclide tracing of river-bed and alluvial sediments are used to determine the role of secondary sources, sediment stores, as potential sources of sediment leaving Emu Creek catchment, southeastern Queensland, Australia. Activity concentrations of 137Cs on the river sediments are consistent with channel erosion being the dominant source at all sites sampled along the river. To characterise the deposition and remobilisation cycles in the catchment, a novel geochemical tracing approach was used. Successive pockets of alluvium were treated as discrete sink terms within geochemical mixing models and their source contributions compared with those of river bed sediments collected adjacent to each alluvial pocket. Three different size fractions were examined; silts and clays (soil/rock type sources to river bed and alluvial sediments at each sampling site was identical for all three different size fractions, but varied along the stream. Combining these findings it is concluded that proximal alluvial stores dominated the supply of sediment to the river at each location, with this being particularly evident at the catchment outlet. Identical contribution of rock type sources to both river bed and alluvial pockets together with the dominant erosion being from channel banks indicates a high degree of 'trading' between the fluvial space and the alluvial space. Hence, management works aimed at primarily reducing the supply of sediments to the outlet of Emu Creek should focus on rehabilitation of channel banks in the lower catchment.

  2. Experiments and Modelling of Coal Pyrolysis under Fluidized Bed Conditions

    Institute of Scientific and Technical Information of China (English)

    ZhangYongzhe; XuXiangdong; 等

    1999-01-01

    The pyrolysis behavior of two Chinese coals has been investigated in a laboratory-scale bubbling fluidized bed system in Siegen University,Germany,Experimental equipment and procedure are introduced.The amounts of pyrolysis species of each coal were measured,calcuated and compared.A new method was presented to determine the needed parameters in FG-DVC model with the experimental results instead of other much more complicated experiments.

  3. Numerical Modeling and Prediction of Bubbling Fluidized Beds

    OpenAIRE

    England, Jonas Andrew

    2011-01-01

    Numerical modeling and prediction techniques are used to determine pressure drop, minimum fluidization velocity and segregation for bubbling fluidized beds. The computational fluid dynamics (CFD) code Multiphase Flow with Interphase eXchange (MFIX) is used to study a two-stage reactor geometry with a binary mixture. MFIX is demonstrated to accurately predict pressure drop versus inlet gas velocity for binary mixtures. A new method is developed to predict the pressure drop versus inlet gas v...

  4. COOLOCE debris bed experiments and simulations investigating the coolability of cylindrical beds with different materials and flow modes

    Energy Technology Data Exchange (ETDEWEB)

    Takasuo, E.; Kinnunen, T.; Holmstroem, S.; Lehtikuusi, T. [VTT Technical Research Centre of Finland (Finland)

    2013-07-15

    The COOLOCE experiments aim at investigating the coolability of debris beds of different geometries, flow modes and materials. A debris bed may be formed of solidified corium as a result of a severe accident in a nuclear power reactor. The COOLOCE-8 test series consisted of experiments with a top-flooded test bed with irregular gravel as the simulant material. The objective was to produce comparison data useful in estimating the effects of different particle materials and the possible effect of the test arrangement on the results. It was found that the dryout heat flux (DHF) measured for the gravel was lower compared to previous experiments with spherical beads, and somewhat lower compared to the early STYX experiments. The difference between the beads and gravel is at least partially explained by the smaller average size of the gravel particles. The COOLOCE-9 test series included scoping experiments examining the effect of subcooling of the water pool in which the debris bed is immersed. The experiments with initially subcooled pool suggest that the subcooling may increase DHF and increase coolability. The aim of the COOLOCE-10 experiments was to investigate the effect of lateral flooding on the DHF a cylindrical test bed. The top of the test cylinder and its sidewall were open to water infiltration. It was found that the DHF is increased compared to a top-flooded cylinder by more than 50%. This suggests that coolability is notably improved. 2D simulations of the top-flooded test beds have been run with the MEWA code. Prior to the simulations, the effective particle diameter for the spherical beads and the irregular gravel was estimated by single-phase pressure loss measurements performed at KTH in Sweden. Parameter variations were done for particle size and porosity used as input in the models. It was found that with the measured effective particle diameter and porosity, the simulation models predict DHF with a relatively good accuracy in the case of spherical

  5. COOLOCE debris bed experiments and simulations investigating the coolability of cylindrical beds with different materials and flow modes

    International Nuclear Information System (INIS)

    The COOLOCE experiments aim at investigating the coolability of debris beds of different geometries, flow modes and materials. A debris bed may be formed of solidified corium as a result of a severe accident in a nuclear power reactor. The COOLOCE-8 test series consisted of experiments with a top-flooded test bed with irregular gravel as the simulant material. The objective was to produce comparison data useful in estimating the effects of different particle materials and the possible effect of the test arrangement on the results. It was found that the dryout heat flux (DHF) measured for the gravel was lower compared to previous experiments with spherical beads, and somewhat lower compared to the early STYX experiments. The difference between the beads and gravel is at least partially explained by the smaller average size of the gravel particles. The COOLOCE-9 test series included scoping experiments examining the effect of subcooling of the water pool in which the debris bed is immersed. The experiments with initially subcooled pool suggest that the subcooling may increase DHF and increase coolability. The aim of the COOLOCE-10 experiments was to investigate the effect of lateral flooding on the DHF a cylindrical test bed. The top of the test cylinder and its sidewall were open to water infiltration. It was found that the DHF is increased compared to a top-flooded cylinder by more than 50%. This suggests that coolability is notably improved. 2D simulations of the top-flooded test beds have been run with the MEWA code. Prior to the simulations, the effective particle diameter for the spherical beads and the irregular gravel was estimated by single-phase pressure loss measurements performed at KTH in Sweden. Parameter variations were done for particle size and porosity used as input in the models. It was found that with the measured effective particle diameter and porosity, the simulation models predict DHF with a relatively good accuracy in the case of spherical

  6. Stormwater and Wastewater Infrastructure Monitoring Test Bed

    Science.gov (United States)

    The growing application of stormwater and wastewater management in urban and urbanizing environments is increasing the demand for monitoring technologies and systems that can provide reliable performance data, in real-time or near real-time, for operation and maintenance decision...

  7. Flow and fracture in water-saturated, unconstrained granular beds

    Directory of Open Access Journals (Sweden)

    Germán eVaras

    2015-06-01

    Full Text Available The injection of gas in a liquid-saturated granular bed gives rise to a wide variety of invasion patterns. Many studies have focused on constrained porous media, in which the grains are fixed in the bed and only the interstitial fluid flows when the gas invades the system. With a free upper boundary, however, the grains can be entrained by the ascending gas or fluid motion, and the competition between the upward motion of grains and sedimentation leads to new patterns. We propose a brief review of the experimental investigation of the dynamics of air rising through a water-saturated, unconstrained granular bed, in both two and three dimensions. After describing the invasion pattern at short and long time, a tentative regime-diagram is proposed. We report original results showing a dependence of the fluidized zone shape, at long times, on the injection flow rate and grain size. A method based on image analysis makes it possible to detect not only the fluidized zone profile in the stationary regime, but also to follow the transient dynamics of its formation. Finally, we describe the degassing dynamics inside the fluidized zone, in the stationary regime. Depending on the experimental conditions, regular bubbling, continuous degassing, intermittent regime or even spontaneous flow-to-fracture transition are observed.

  8. Host Searching and Aggregation Activity of Recently Fed and Unfed Bed Bugs (Cimex lectularius L.

    Directory of Open Access Journals (Sweden)

    Matthew D. Reis

    2011-05-01

    Full Text Available Groups of starved, virgin adult male or female bed bugs were stimulated to search for a host by the presence of a heated artificial feeder. Some of the bed bug groups were allowed to obtain a blood meal and some were not. After the removal of the feeder, bed bugs were observed throughout the scotophase to record their searching and aggregation behavior. Groups of male and female bed bugs that were unable to obtain a blood meal continued to search in the arena for the majority of the scotophase. Bed bugs that were able to obtain a blood meal returned to their shelter to aggregate 30 min after feeding. Overall, the proportion of bed bugs aggregating in shelters during the scotophase was significantly greater for those that had fed successfully than those that had not. However, all bed bugs, regardless of feeding status, began to return to shelters to aggregate 2 h prior to the photophase.

  9. SPATIAL AND TEMPORAL CHANGES IN THE BRAHMAPUTRA RIVER BED

    Institute of Scientific and Technical Information of China (English)

    Prabhata K.SWAMEE; Barham PARKASH; Santanu SARMA

    2006-01-01

    A mathematical model based on data for the period 1957-1988 representing changes in space and time in the bed morphology of the 623 km long alluvial reach of the Brahmaputra River in Assam State, India has been developed. This model reveals that in the upper reaches the bed level decreases downstream exponentially with distance from a reference point, while in the lower reaches the exponential decrease is at a smaller rate probably due to differences in tectonic setting. The lower reach is marked by sinusoidal oscillations with a time period of about 9 yr. High runoff in 1977 seems to have caused a significant change as the maximum, average, and minimum bed level were decreasing before 1977 and these increased just after 1977 and then started decreasing at a lower rate than before. Smaller changes in shorter reaches governed by input of discharge and sediment from tributaries are superimposed on the overall degradation/aggradation character. The variation in degradation/aggradation with time is sinusoidal with a wavelength of 4,450 km before 1977 that reduces to about 1,038 km after 1977.

  10. Bed agglomeration in fluidized combustor fueled by wood and rice straw blends

    NARCIS (Netherlands)

    Thy, P.; Jenkins, B.M.; Williams, R.B.; Lesher, C.E.; Bakker, R.R.

    2010-01-01

    Petrographic techniques have been used to examine bed materials from fluidized bed combustion experiments that utilized wood and rice straw fuel blends. The experiments were conducted using a laboratory-scale combustor with mullite sand beds, firing temperatures of 840 to 1030 °C, and run durations

  11. Filter bed systems treating domestic wastewater in the Nordic countries - Performance and reuse of filter media

    DEFF Research Database (Denmark)

    Jenssen, Petter D.; Krogstad, T.; Paruch, A.M.;

    2010-01-01

    Nine filter beds have been constructed in the Nordic countries, Denmark, Finland, Norway and Sweden. Filter beds consist of a septic tank followed by an aerobic pre-treatment biofilter and a subsequent saturated flow grass-covered filter. Thus, filter beds are similar to subsurface flow constructed...

  12. Modeling N2O Reduction and Decomposition in a Circulating Fluidized bed Boiler

    DEFF Research Database (Denmark)

    Johnsson, Jan Erik; Åmand, Lars-Erik; Dam-Johansen, Kim;

    1996-01-01

    The N2O concentration was measured in a circulating fluidized bed boiler of commercial size. Kinetics for N2O reduction by char and catalytic reduction and decomposition over bed material from the combustor were determined in a laboratory fixed bed reactor. The destruction rate of N2O in the comb...

  13. Fluidized bed and method and system for gas component capture

    Energy Technology Data Exchange (ETDEWEB)

    Krutka, Holly; Wilson, Cody; Starns, Travis

    2016-05-31

    The present disclosure is directed to a process that allows dry sorbents to remove a target constituent, such as carbon dioxide (CO.sub.2), from a gas stream. A staged fluidized bed separator enables gas and sorbent to move in opposite directions. The sorbent is loaded with target constituent in the separator. It is then transferred to a regenerator where the target constituent is stripped. The temperature of the separator and regenerator are controlled. After it is removed from the regenerator, the sorbent is then transferred back to the separator.

  14. Tapahtuman järjestäminen : kansainvälinen bachatafestivaali

    OpenAIRE

    Salo, Susanna

    2009-01-01

    Opinnäytetyöni tarkoitus on kuvailla, miten kansainvälinen bachatafestivaali eli Finland 2nd International Bachata Festival järjestettiin Tampereelle ja Helsinkiin kesäkuussa 2009. Bachata on romanttinen musiikki- ja tanssityyli Dominikaanisesta tasavallasta. Tapahtuma järjestettiin toista kertaa, mutta ensimmäistä kertaa uudella konseptilla, isompana tapahtumana kahdessa kaupungissa. Tarkoituksena oli tutkia myös tapahtuman järjestäjän motiiveja tapahtuman järjestämiseen sekä tapahtuma...

  15. Microbial biomass and productivity in seagrass beds

    Science.gov (United States)

    Moriarty, D. J.; Boon, P. I.; Hansen, J. A.; Hunt, W. G.; Poiner, I. R.; Pollard, P. C.; Skyring, G. W.; White, D. C.

    1985-01-01

    Different methods for measuring the rates of processes mediated by bacteria in sediments and the rates of bacterial cell production have been compared. In addition, net production of the seagrass Zostera capricorni and bacterial production have been compared and some interrelationships with the nitrogen cycle discussed. Seagrass productivity was estimated by measuring the plastochrone interval using a leaf stapling technique. The average productivity over four seasons was 1.28 +/- 0.28 g C m-2 day-1 (mean +/- standard deviation, n = 4). Bacterial productivity was measured five times throughout a year using the rate of tritiated thymidine incorporated into DNA. Average values were 33 +/- 12 mg C m-2 day-1 for sediment and 23 +/- 4 for water column (n = 5). Spatial variability between samples was greater than seasonal variation for both seagrass productivity and bacterial productivity. On one occasion, bacterial productivity was measured using the rate of 32P incorporated into phospholipid. The values were comparable to those obtained with tritiated thymidine. The rate of sulfate reduction was 10 mmol SO4(-2) m-2 day-1. The rate of methanogenesis was low, being 5.6 mg CH4 produced m-2 day-1. A comparison of C flux measured using rates of sulfate reduction and DNA synthesis indicated that anaerobic processes were predominant in these sediments. An analysis of microbial biomass and community structure, using techniques of phospholipid analysis, showed that bacteria were predominant members of the microbial biomass and that of these, strictly anaerobic bacteria were the main components. Ammonia concentration in interstitial water varied from 23 to 71 micromoles. Estimates of the amount of ammonia required by seagrass showed that the ammonia would turn over about once per day. Rapid recycling of nitrogen by bacteria and bacterial grazers is probably important.

  16. Healthcare Facility Bed Types And Counts

    Data.gov (United States)

    U.S. Department of Health & Human Services — The California Department of Public Health (CDPH), Center for Health Care Quality, Licensing and Certification (L&C) Program licenses more than 30 types of...

  17. Potential of stale seed bed preparation in integrated and organic crop production

    NARCIS (Netherlands)

    Lotz, L.A.P.; Weide, van der R.Y.; Bleeker, P.O.; Groeneveld, R.M.W.

    2004-01-01

    This paper reviews a study over six years to assess the potential of stale seed beds in various crops. Using stale seed beds, the farmer has to optimize the combined effect of, firstly, the delaying of the sowing time of the crop and, secondly, the timing of the stale seed bed (i.e. the period after

  18. Equilibrium modeling of gasification: Gibbs free energy minimization approach and its application to spouted bed and spout-fluid bed gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Jarungthammachote, S.; Dutta, A. [Energy Field of Study, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klongluang, Pathumthani 12120 (Thailand)

    2008-06-15

    Spouted beds have been found in many applications, one of which is gasification. In this paper, the gasification processes of conventional and modified spouted bed gasifiers were considered. The conventional spouted bed is a central jet spouted bed, while the modified spouted beds are circular split spouted bed and spout-fluid bed. The Gibbs free energy minimization method was used to predict the composition of the producer gas. The major six components, CO, CO{sub 2}, CH{sub 4}, H{sub 2}O, H{sub 2} and N{sub 2}, were determined in the mixture of the producer gas. The results showed that the carbon conversion in the gasification process plays an important role in the model. A modified model was developed by considering the carbon conversion in the constraint equations and in the energy balance calculation. The results from the modified model showed improvements. The higher heating values (HHV) were also calculated and compared with the ones from experiments. The agreements of the calculated and experimental values of HHV, especially in the case of the circular split spouted bed and the spout-fluid bed were observed. (author)

  19. The suitability of horse manure and bedding materials for combustion

    Energy Technology Data Exchange (ETDEWEB)

    Tyni, S.; Tiainen, M. S.; Laitinen, R. S. (Univ. of Oulu, Dept. of Chemistry (Finland)). email: sanna.tyni@oulu.fi

    2009-07-01

    The number of horses has increased in Finland since 1994 approximately by 2000 horse/ year and 2008 there was almost 70000 registered horses and ponies in Finland. This has derived to a considerable number of new stables at city area where the waste management, particularly of the mixture of manure and bedding material, is a challenge. These stables have disposed their residues often by land filling. The present legislation prohibits the dispose of organic material by land filling since the anaerobic decomposition emits for example methane that is a greenhouse gas. The legislation also regulates using of manure as fertilizer in fields. This leads to the situation where stable owners have urge for new ways to dispose of residues. In Finland peat, sawdust, and straw are commonly used as a bedding material for horses in stable boxes. The more important function of the bedding material is to keep the boxes dry and clean by absorbing urine. The selection of bedding material depends on the properties of the materials such as availability, price, absorption capacity, and hygiene properties. Composting of sawdust is slower than peat, therefore mixture of manure and sawdust is not preferred for utilization as fertilizer. Additionally use of the manure residues as fertilizers is limited by impurities such as plant seeds in manure. Combustion would be attractive way to solve disposal problems of the mixture of manure and bedding materials. At the moment legislation in Finland defines manure residues as a waste. Therefore the combustion is only allowed in waste combustion units. If the combustion of the manure residues would be allowed at farms or at small local boilers, it enables farms to have better degree of self-sufficiency of energy. The utilization of these new materials as a fuel demands study of combustion properties of these biomasses. It is also essential to have knowledge of chemical composition and behaviour of ashes, when the final disposing is considered e.g. as

  20. Ammonia, Total Reduced Sulfides, and Greenhouse Gases of Pine Chip and Corn Stover Bedding Packs.

    Science.gov (United States)

    Spiehs, Mindy J; Brown-Brandl, Tami M; Parker, David B; Miller, Daniel N; Berry, Elaine D; Wells, James E

    2016-03-01

    Bedding materials may affect air quality in livestock facilities. Our objective in this study was to compare headspace concentrations of ammonia (NH), total reduced sulfides (TRS), carbon dioxide (CO), methane (CH), and nitrous oxide (NO) when pine wood chips ( spp.) and corn stover ( L.) were mixed in various ratios (0, 10, 20, 30, 40, 60, 80, and 100% pine chips) and used as bedding with manure. Air samples were collected from the headspace of laboratory-scaled bedded manure packs weekly for 42 d. Ammonia concentrations were highest for bedded packs containing 0, 10, and 20% pine chips (equivalent to 501.7, 502.3, and 502.3 mg m, respectively) in the bedding mixture and were lowest when at least 80% pine chips were used as bedding (447.3 and 431.0 mg m, respectively for 80 and 100% pine chip bedding). The highest NH concentrations were observed at Day 28. The highest concentration of TRS was observed when 100% pine chips were used as bedding (11.4 µg m), with high concentrations occurring between Days 7 and 14, and again at Day 35. Greenhouse gases were largely unaffected by bedding material but CH and CO concentrations increased as the bedded packs aged and NO concentrations were highly variable throughout the incubation. We conclude that a mixture of bedding material that contains 30 to 40% pine chips may be the ideal combination to reduce both NH and TRS emissions. All gas concentrations increased as the bedded packs aged, suggesting that frequent cleaning of facilities would improve air quality in the barn, regardless of bedding materials used. PMID:27065410

  1. Ammonia, Total Reduced Sulfides, and Greenhouse Gases of Pine Chip and Corn Stover Bedding Packs.

    Science.gov (United States)

    Spiehs, Mindy J; Brown-Brandl, Tami M; Parker, David B; Miller, Daniel N; Berry, Elaine D; Wells, James E

    2016-03-01

    Bedding materials may affect air quality in livestock facilities. Our objective in this study was to compare headspace concentrations of ammonia (NH), total reduced sulfides (TRS), carbon dioxide (CO), methane (CH), and nitrous oxide (NO) when pine wood chips ( spp.) and corn stover ( L.) were mixed in various ratios (0, 10, 20, 30, 40, 60, 80, and 100% pine chips) and used as bedding with manure. Air samples were collected from the headspace of laboratory-scaled bedded manure packs weekly for 42 d. Ammonia concentrations were highest for bedded packs containing 0, 10, and 20% pine chips (equivalent to 501.7, 502.3, and 502.3 mg m, respectively) in the bedding mixture and were lowest when at least 80% pine chips were used as bedding (447.3 and 431.0 mg m, respectively for 80 and 100% pine chip bedding). The highest NH concentrations were observed at Day 28. The highest concentration of TRS was observed when 100% pine chips were used as bedding (11.4 µg m), with high concentrations occurring between Days 7 and 14, and again at Day 35. Greenhouse gases were largely unaffected by bedding material but CH and CO concentrations increased as the bedded packs aged and NO concentrations were highly variable throughout the incubation. We conclude that a mixture of bedding material that contains 30 to 40% pine chips may be the ideal combination to reduce both NH and TRS emissions. All gas concentrations increased as the bedded packs aged, suggesting that frequent cleaning of facilities would improve air quality in the barn, regardless of bedding materials used.

  2. Potential of Essential Oil-Based Pesticides and Detergents for Bed Bug Control.

    Science.gov (United States)

    Singh, Narinderpal; Wang, Changlu; Cooper, Richard

    2014-12-01

    The bed bug, (Cimex lectularius L.), is a difficult pest to control. Prevalence of insecticide resistance among bed bug populations and concerns over human-insecticide exposure has stimulated the development of alternative bed bug control materials. Many essential oil-based pesticides and detergent insecticides targeting bed bugs have been developed in recent years. We evaluated the efficacy of nine essential oil-based products and two detergents using direct spray and residual contact bioassays in the laboratory. Two conventional insecticides, Temprid SC (imidacloprid and β-cyfluthrin) and Demand CS (λ-cyhalothrin), were used for comparison. Among the 11 nonsynthetic insecticides tested, only EcoRaider (1% geraniol, 1% cedar extract, and 2% sodium lauryl sulfate) and Bed Bug Patrol (0.003% clove oil, 1% peppermint oil, and 1.3% sodium lauryl sulfate) caused >90% mortality of nymphs in direct spray and forced exposure residual assays. However, the efficacy of EcoRaider and Bed Bug Patrol was significantly lower than that of Temprid SC and Demand CS in choice exposure residual bioassay. Direct spray of EcoRaider caused 87% egg mortality, whereas the other nonsynthetic insecticides had little effect on bed bug eggs. EcoRaider and Bed Bug Patrol did not exhibit detectable repellency against bed bugs in the presence of a carbon dioxide source. These findings suggest that EcoRaider and Bed Bug Patrol are potentially useful pesticides for controlling bed bug infestations, but further testing in naturally infested environments is needed. PMID:26470082

  3. Comparison of the Effects of Fluidized-Bed and Fixed-Bed Reactors in Microwave-Assisted Catalytic Decomposition of TCE by Hydrogen

    OpenAIRE

    Lili Ren; Jin Zhang

    2012-01-01

    Trichloroethylene (TCE) decomposition by hydrogen with microwave heating under different reaction systems was investigated. The activities of a series of catalysts for microwave-assisted TCE hydrodechlorination were tested through the fixed-bed and the fluidized-bed reactor systems. This study found that the different reaction system is suitable for different catalyst type. And there is an interactive relationship between the catalyst type and the reaction bed type.

  4. Comparison of the Effects of Fluidized-Bed and Fixed-Bed Reactors in Microwave-Assisted Catalytic Decomposition of TCE by Hydrogen

    Directory of Open Access Journals (Sweden)

    Lili Ren

    2012-01-01

    Full Text Available Trichloroethylene (TCE decomposition by hydrogen with microwave heating under different reaction systems was investigated. The activities of a series of catalysts for microwave-assisted TCE hydrodechlorination were tested through the fixed-bed and the fluidized-bed reactor systems. This study found that the different reaction system is suitable for different catalyst type. And there is an interactive relationship between the catalyst type and the reaction bed type.

  5. Simultaneous heat and mass transfer in packed bed brying of seeds having a mucilage coating

    Directory of Open Access Journals (Sweden)

    M. M. Prado

    2008-03-01

    Full Text Available The simultaneous heat and mass transfer between fluid phase and seeds having a mucilaginous coating was studied during packed bed drying. To describe the process, a two-phase model approach was employed, in which the effects of bed shrinkage and nonconstant physical properties were considered. The model took into account bed contraction by employing moving coordinates. Equations relating shrinkage and structural parameters of the packed bed with moisture content, required in the drying model, were developed from experimental results in thick-layer bed drying. The model verification was based on a comparison between experimental and predicted data on moisture content and temperature along the bed. Parametric studies showed that the application of correlations capable of incorporating changes in bed properties gives better data simulation. By experimental-theoretical analysis, the importance of shrinkage for a more accurate interpretation of heat and mass transfer phenomena in the drying of porous media composed of mucilaginous seeds is corroborated.

  6. Bed agglomeration in fluidized combustor fueled by wood and rice straw blends

    DEFF Research Database (Denmark)

    Thy, Peter; Jenkins, Brian; Williams, R.B.;

    2010-01-01

    Abstract Petrographic techniques have been used to examine bed materials from fluidized bed combustion experiments that utilized wood and rice straw fuel blends. The experiments were conducted using a laboratory-scale combustor with mullite sand beds, firing temperatures of 840 to 1030 °C, and run...... durations of 5.5 h. A narrow continuous zone borders virtually all bed particles. The highest concentrations of potassium are found in this surface zone that also is enriched in appreciable amounts of other elements. Thin discontinuous films of adhesive cement, formed preferentially on surfaces and contact...... areas between bed particles, ultimately led to bed agglomeration. The interfaces and the presence of gas bubbles in the cement suggest a bonding material with a high surface tension and a liquid state. The cement films originate by filling of irregularities on individual and partially agglomerated bed...

  7. Using research and education to implement practical bed bug control programs in multifamily housing.

    Science.gov (United States)

    Bennett, Gary W; Gondhalekar, Ameya D; Wang, Changlu; Buczkowski, Grzegorz; Gibb, Timothy J

    2016-01-01

    Multifamily housing facilities serving low-income populations have been at the forefront of bed bug outbreaks. Research conducted in the past 8 years has consistently proven that integrated pest management (IPM) is the best approach for successful suppression of bed bug infestations. Bed bug IPM in multifamily settings is especially dependent upon a collaborative community or building-wide effort involving residents, building staff and pest control technicians. Other components of a bed bug IPM program include regular monitoring to detect early-stage bed bug infestations and combined use of non-chemical and chemical interventions. Lastly, to reduce reinfestation rates and costs associated with bed bug control, it is critical to continue periodic monitoring and implement preventive control measures even after successful elimination of bed bugs has been achieved. PMID:26251256

  8. Experimental and theoretical investigation of anaerobic fluidized bed biofilm reactors

    Directory of Open Access Journals (Sweden)

    M. Fuentes

    2009-09-01

    Full Text Available This work presents an experimental and theoretical investigation of anaerobic fluidized bed reactors (AFBRs. The bioreactors are modeled as dynamic three-phase systems. Biochemical transformations are assumed to occur only in the fluidized bed zone. The biofilm process model is coupled to the system hydrodynamic model through the biofilm detachment rate; which is assumed to be a first-order function of the energy dissipation parameter and a second order function of biofilm thickness. Non-active biomass is considered to be particulate material subject to hydrolysis. The model includes the anaerobic conversion for complex substrate degradation and kinetic parameters selected from the literature. The experimental set-up consisted of two mesophilic (36±1ºC lab-scale AFBRs (R1 and R2 loaded with sand as inert support for biofilm development. The reactor start-up policy was based on gradual increments in the organic loading rate (OLR, over a four month period. Step-type disturbances were applied on the inlet (glucose and acetic acid substrate concentration (chemical oxygen demand (COD from 0.85 to 2.66 g L-1 and on the feed flow rate (from 3.2 up to 6.0 L d-1 considering the maximum efficiency as the reactor loading rate switching. The predicted and measured responses of the total and soluble COD, volatile fatty acid (VFA concentrations, biogas production rate and pH were investigated. Regarding hydrodynamic and fluidization aspects, variations of the bed expansion due to disturbances in the inlet flow rate and the biofilm growth were measured. As rate coefficients for the biofilm detachment model, empirical values of 3.73⋅10(4 and 0.75⋅10(4 s² kg-1 m-1 for R1 and R2, respectively, were estimated.

  9. River sedimentation and channel bed characteristics in northern Ethiopia

    Science.gov (United States)

    Demissie, Biadgilgn; Billi, Paolo; Frankl, Amaury; Haile, Mitiku; Lanckriet, Sil; Nyssen, Jan

    2016-04-01

    Excessive sedimentation and flood hazard are common in ephemeral streams which are characterized by flashy floods. The purposes of this study was to investigate the temporal variability of bio-climatic factors in controlling sediment supply to downstream channel reaches and the effect of bridges on local hydro-geomorphic conditions in causing the excess sedimentation and flood hazard in ephemeral rivers of the Raya graben (northern Ethiopia). Normalized Difference Vegetation Index (NDVI) was analyzed for the study area using Landsat imageries of 1972, 1986, 2000, 2005, 2010, and 2012). Middle term, 1993-2011, daily rainfall data of three meteorological stations, namely, Alamata, Korem and Maychew, were considered to analyse the temporal trends and to calculate the return time intervals of rainfall intensity in 24 hours for 2, 5, 10 and 20 years using the log-normal and the Gumbel extreme events method. Streambed gradient and bed material grain size were measured in 22 river reaches (at bridges and upstream). In the study catchments, the maximum NDVI values were recorded in the time interval from 2000 to 2010, i.e. the decade during which the study bridges experienced the most severe excess sedimentation problems. The time series analysis for a few rainfall parameters do not show any evidence of rainfall pattern accountable for an increase in sediment delivery from the headwaters nor for the generation of higher floods with larger bedload transport capacities. Stream bed gradient and bed material grain size data were measured in order to investigate the effect of the marked decrease in width from the wide upstream channels to the narrow recently constructed bridges. The study found the narrowing of the channels due to the bridges as the main cause of the thick sedimentation that has been clogging the study bridges and increasing the frequency of overbank flows during the last 15 years. Key terms: sedimentation, ephemeral streams, sediment size, bridge clogging

  10. Industrial application of the technique of removing Mo by a combination of moving packed bed and fluidized bed ion exchange

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The application of the technique of removing molybdenum by moving packed bed and fluidized bed ion-exchange in a factory was described. The data showed that the Mo removal efficiency is above 99%, and the Mo content inAFT (Ammonium Paratungstate) is controlled steadily below 18 × 10-6, in the case of treating the feed liquor containing Mo1.4 g/L. The technique is simple and convenient in operation, good reusability of resin, loss consumption of desorption rea-gent and little pollution on environment. The loss of tungsten is less than 0.5%. The technique has been proved to be aneconomical and efficient process for Mo removal.

  11. The Tore Supra Lower Hybrid Test Bed : improvements and applications

    International Nuclear Information System (INIS)

    Within the CIMES project framework in Tore Supra, a klystron TH2103C (3.7 GHz) is under development at THALES ELECTRON DEVICES. It differs from the previous klystrons used in Tore Supra generator mainly in that it has no modulating anode, the RF output power will reach 700 kW CW, by raising the High Voltage value to 76 kV and a beam current up to 23 A. The Tore Supra test bed is a dedicated facility used for high power tests on RF components or on RF transmitters. It has been improved to integrate the TH2103C klystron and a specific 100 kV solide state switch which control the beam current. Since April 2005, the integration of the first tube (without modulating anode) and the 100 kV switch has been completed in the Test Bed and has allowed the modifications and tests of the interfaces and security system for the devices. Improvements were also made on the cooling loop flow to dissipate a power of 1750 kW CW. With these devices, the RF power routinely available in the Lower Hybrid Test Bed is 400 kW CW. With the development of the TH2103C, detailed studies and tests on RF components which will be used up to 750 kW CW on match load or 700 kW on VSWR = 1.4, are necessary to evaluate their performances and thermal behaviour. The test a crucial component, the recombiner, which adds the RF powers coming from the two RF outputs of the TH2103C and inject the resulted power into one WR284 waveguide to a test load or to the plasma, was completed. Two tests have been performed : a thermal study with 400 kW during 1000 s, and RF pulsed tests on short cuts to increase the value of the electric field inside the component. The experiments and calculations (ANSYS and HFSS codes) validate the use of this device with the TH2103C. A module made with two different Beryllium Oxide RF windows, has been under test. The losses on each window are measured by calorimetric measurements and evaluated by computation with HFSS and ANSYS code. The results are compared. In this paper, the

  12. Pattern recognition of the acoustic Sea-bed Profiling —Records and sea-bed geological classification

    Institute of Scientific and Technical Information of China (English)

    JI Wenyun; LIN Yijun; ZHANG Shuying

    2001-01-01

    The physical properties of pattern characteristics for typical Acoustic Sea-bed Profiling Records (ASPRs) in the area of Changjiang Estuary and the East China Sea are analyzed in this paper. Nine pattern characteristics are summarized and it was shown that 9 geological categories can be determined by 4 pattern characteristics. Based on the above analysis, a Bayes-based pattern characteristics classifier for interpretation of ASPRs is developed.

  13. Report on the development of equipment and techniques for drilling and machining bedded salt

    International Nuclear Information System (INIS)

    Equipment and techniques are being developed in the evaluation of bedded salt as a storage media for nuclear waste. Beginning with the Conceptual Design Report for the Waste Isolation Pilot Plant and continuing with field and laboratory experiments indicate the need for a more complete understanding of bedded salt as an engineering material. This report discusses various aspects of bedded salt in its comparison to other materials, machining methods in the laboratory and equipment development to support experiments in mines

  14. Packed bed carburization of tantalum and tantalum alloy

    Science.gov (United States)

    Lopez, Peter C.; Rodriguez, Patrick J.; Pereyra, Ramiro A.

    1999-01-01

    Packed bed carburization of a tantalum or tantalum alloy object. A method for producing corrosion-resistant tantalum or tantalum alloy objects is described. The method includes the steps of placing the object in contact with a carburizing pack, heating the packed object in vacuum furnace to a temperature whereby carbon from the pack diffuses into the object forming grains with tantalum carbide along the grain boundaries, and etching the surface of the carburized object. This latter step removes tantalum carbides from the surface of the carburized tantalum object while leaving the tantalum carbide along the grain boundaries.

  15. Measurement and modelling of bed shear induced by solitary waves

    Digital Repository Service at National Institute of Oceanography (India)

    JayaKumar, S.

    be considered in pipeline routing. 10.6. Future directions Bed shear stresses due to N-shaped waves were estimated using the method described in this thesis. However, due to want of time, this data was not considered in this thesis. The data pertaining to N....K.C. and Erali, D.R., 1974. Large diameter underwater pipeline for nuclear power plant designed against soil liquefaction. Offshore Technology Conference, Dallas, p.^pp. 597-606. Cokgor, S., 2002. Hydrodynamic forces on a partly buried cylinder exposed...

  16. Test bed experiments for various telerobotic system characteristics and configurations

    Science.gov (United States)

    Duffie, Neil A.; Wiker, Steven F.; Zik, John J.

    1990-01-01

    Dexterous manipulation and grasping in telerobotic systems depends on the integration of high-performance sensors, displays, actuators and controls into systems in which careful consideration has been given to human perception and tolerance. Research underway at the Wisconsin Center for Space Automation and Robotics (WCSAR) has the objective of enhancing the performance of these systems and their components, and quantifying the effects of the many electrical, mechanical, control, and human factors that affect their performance. This will lead to a fundamental understanding of performance issues which will in turn allow designers to evaluate sensor, actuator, display, and control technologies with respect to generic measures of dexterous performance. As part of this effort, an experimental test bed was developed which has telerobotic components with exceptionally high fidelity in master/slave operation. A Telerobotic Performance Analysis System has also been developed which allows performance to be determined for various system configurations and electro-mechanical characteristics. Both this performance analysis system and test bed experiments are described.

  17. Variety in dustiness and hygiene quality of peat bedding.

    Science.gov (United States)

    Airaksinen, Sanna; Heiskanen, Minna-Liisa; Heinonen-Tanski, Helvi; Laitinen, Juha; Laitinen, Sirpa; Linnainmaa, Markku; Rautiala, Sirpa

    2005-01-01

    Respiratory exposure to organic dust induces chronic pulmonary diseases both in farmers and horses. The aim of this study was to examine the variation of dustiness and hygiene quality of peat moss bedding. Materials studied were weakly decomposed sphagnum peat (A), weakly decomposed sphagnum peat warmed up in storage (> 30 degrees C) (B) and two more decomposed few-flowered sedge peats (C and D). The geometric mean of mesophilic fungi, thermotolerant fungi and thermophilic actinomycetes were determined from the material. Samples of inhalable dust and endotoxins were collected with IOM samplers and respirable dust with 10M foam samplers when the peat was rotated in a cylinder. The number of particles was detected with an optical particle counter. An LAL assay was used for analysing endotoxins from the filter samples. There were differences in the hygiene quality and dustiness between peat materials (p particles were smaller in the few-flowered peats (C-D) than in the sphagnum peats (A-B). It is concluded that there are differences in the dustiness and hygiene quality of peat bedding. PMID:16028867

  18. Global- and local-scale characterisation of bed surface structure in coarse-grained alluvial rivers

    Science.gov (United States)

    Powell, Mark; Ockelford, Annie; Nguyen, Thao; Wood, Jo; Rice, Steve; Reid, Ian; Tate, Nick

    2013-04-01

    It is widely recognised that adjustments in bed surface grain size (texture) and grain arrangement (structure) exert significant controls on the stability of coarse-grained alluvial rivers. Modifications to bed surface texture and structure occur during active sediment transport and are mediated by the process of mobile armouring which concentrates coarser-than-average particles on the surface and organises them into a variety of grain- and bedform-scale configurations. Textural aspects of surface armouring are well understood to the extent that sediment transport models can be used to predict the size distribution of armours that develop under different sediment supply regimes and shear stresses. Research has also found that the adjustment of bed surface grain size is often patchy and that the development of finer-grained and coarser-grained areas of the bed has important implications for both the rate and grain size of transported sediment. The structural aspects of stream-bed armouring, however, are less well understood, largely because of the difficulty of recognising and characterising bedforms and bed-structures that have dimensions similar to their constituent particles. Moreover, bed structure is generally parameterised using global scale descriptors of the bed surface such that information on the spatial heterogeneity of the structure is lost. The aim of this poster is to characterise the structural characteristics of water-worked river gravels, paying particular attention to quantifying the spatial heterogeneity of those characteristics using local scale descriptors. Results reported from a number of flume experiments designed to simulate the spatio-temporal evolution of bed configurations (surface texture and structure) as the system adjusts to a condition of equilibrium transport are used to evaluate the spatial variability of bed surface structure and explore its significance for modelling sediment transport rates in gravel-bed rivers. Keywords: bed

  19. VERIFICATION AND COMPARISON OF FORMULAS FOR BED LOAD TRANSPORT

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Several typical formulas for bed load transport are examinedbased on field data in this paper. It is concluded that, the Einstein formula provides good estimates for the bed load transport rate while other ones predict much lower transport rates. The main reason for the under-prediction is that Dp, the effective diameter of particles, is too large as a representative diameter of the bed material for gravel streams with partially movable bed. Performance of these formulas can be significantly improved if D35 is adopted instead of Dp.

  20. Improved Gasifier Availability with Bed Material and Additives

    Energy Technology Data Exchange (ETDEWEB)

    Grootjes, A.J.; Van der Meijden, C.M.; Visser, H.J.M.; Van der Drift, A. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2013-07-15

    In order to valorize several feedstock, gasification is one of the technologies developed over the past decades. ECN developed the MILENA gasifier. In order for MILENA to become a commercial success, the gasifier needs to be feedstock flexible, robust and economically sound, operating with high availability. One of the characteristics of MILENA is high efficiency but with a higher tar content, compared to some other Dual Fluidized Bed (DFB) gasifiers. In order to reduce the issues that are associated with high tar levels in the product gas, the effect of a number of primary measures was studied. This paper presents results obtained in the last two years, focused on improving the gasifier availability by conducting experiments in a 25 kWth lab scale MILENA gasifier. Amongst others, gas composition, tar content and calorific value of the product gas were compared. Scanning Electron Microscope analysis was used to investigate bed material changes. Results show that Austrian olivine can be activated by Fuel B as well as by Additive A and B. The water-gas shift reaction is enhanced and the tar content is reduced significantly, especially the heavy tars that dominate the tar dew point. Activated olivine has a calcium-rich layer. The results show that with MILENA, we are able to lower and control the tar dew point, which will possibly increase the availability of a MILENA gasifier.

  1. Plasma vasopressin and renin activity in women exposed to bed rest and +G/z/ acceleration

    Science.gov (United States)

    Keil, L. C.; Ellis, S.

    1976-01-01

    To study the effect of prolonged recumbency on plasma vasopressin and renin activity, eight women were subjected to 17 days of absolute bed rest. The tolerance to +3G vertical acceleration of the subjects was tested before and after 14 days of bed rest. From day 2 and through day 17 of bed rest, plasma arginine vasopressin (AVP) levels were reduced 33%. Plasma renin activity (PRA) increased 91% above ambulatory control values from days 10 through 15 of bed rest. When compared to precentrifuge values, exposure to vertical acceleration prior to bed rest provoked a 20-fold rise in mean plasma AVP but resulted in only a slight increase in PRA. After bed rest, acceleration increased plasma AVP 7-fold; however, the magnitude of this increase was less than the post +3G acceleration value obtained prior to bed rest. After bed rest, no significant rise was noted in PRA following +3G acceleration. This study demonstrates that prolonged bed rest leads to a significant rise in the PRA of female subjects, while exposure to positive vertical acceleration provokes a marked rise in plasma AVP.

  2. Dryout heat flux and flooding phenomena in debris beds consisting of homogeneous diameter particles

    International Nuclear Information System (INIS)

    Since the TMI-2 accident, which occurred in 1979, necessity of understanding phenomena associated with a severe accident have been recognized and researches have been conducted in many countries. During a severe accident of a light water reactor, a debris bed consisting of the degraded core materials would be formed. Because the debris bed continues to release decay heat, the debris bed would remelt when the coolable geometry is not maintained. Thus the degraded core coolability experiments to investigate the influence of the debris particle diameter and coolant flow conditions on the coolability of the debris bed and the flooding experiments to investigate the dependence of flooding phenomena on the configuration of the debris bed have been conducted in JAERI. From the degraded core coolability experiments, the following conclusions were derived; the coolability of debris beds would be improved by coolant supply into the beds, Lipinski's 1-dimensional model shows good agreement with the measured dryout heat flux for the beds under stagnant and forced flow conditions from the bottom of the beds, and the analytical model used for the case that coolant is fed by natural circulation through the downcomer reproduces the experimental results. And the following conclusions were given from the flooding experiments ; no dependence between bed height and the flooding constant exists for the beds lower than the critical bed height, flooding phenomena of the stratified beds would be dominated by the layer consisting of smaller particles, and the predicted dryout heat flux by the analytical model based on the flooding theory gives underestimation under stagnant condition. (author)

  3. Ability of the bed bug (Hemiptera: Cimicidae) defensive secretions (E)-2-hexenal and (E)-2-octenal to attract adult bed bugs

    Science.gov (United States)

    Accurate and timely surveillance of bed bug infestations is critical for development of effective control strategies. While the bed bug produced volatiles (E)-2-hexenal and (E)-2-octenal are considered defensive secretions, through use of EthoVision® video-tracking software we demonstrate that low ...

  4. Effect of promoters on dynamics of gas-solid fluidized bed-Statistical and ANN approaches

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this study, a bubbling fluidized bed column, 99 mm in inside diameter and 960 mm in height, was used to investigate the effect of rod and disc promoters on fluctuation and expansion ratios. Factorial design (statistical approach) and artificial neural network (ANN) models were developed to predict the fluctuation and expansion ratios in this gas-solid fluidized bed with varying gas flow rates, bed heights, particle sizes and densities. The fluctuation and expansion predicted using these statistical and ANN models, for beds with and without promoters, were found to agree well with corresponding experiments. The statistical model was found to be superior to the ANN model due to its ability to take into account both individual and interactive effects. The rod promoters were found to be more effective in reducing bed fluctuation, and in increasing bed expansion at high gas mass velocities.

  5. Comparison of Fixed and Fluidized Beds Adsorber with Economic, Engineering, and Environmental approach

    Directory of Open Access Journals (Sweden)

    SEDIGHEH ATRKAR-ROSHAN

    2015-10-01

    Full Text Available Release  Volatile  organic  compounds  (VOCs  as  environmental  and  occupational  pollutant  cause  macro perspective affect such as climate change, humans and economic consequences. Although fixed bed absorber is widely used as a controlling method because of its economically and availability, but these absorbers are facing some issue like high pressure drop, non-uniform distribution of fluid, channeling and blocking. Fixed and fluidized beds adsorbent was compared from three economic, environmental and engineering perspectives using Multi Criteria Decision Making analysis (MCDA technique. An annular fluidized bed adsorber was designed and charged with 50-100 µm (100-140 ASTM mesh activated carbon (AC particles. Effects of factors like flow rate, particle size, inlet concentration and adsorption capacity of VOCs was investigated under steady state. In the flow rate less than 0.25(Lit.min-1, inlet gas slowly passes through the void spaces of the bed’s particles. By increasing the inlet flow from 0.3(Lit/min-1, bubbles start to form in the bed and the bed pressure drop decrease. The pressure drop of 6 (g of AC in minimum fluidization velocity was 20(KN.m-2. However, the pressure drop of 10 and 20(g of AC were 150 and 420(KN.m-2 respectively. “maximin” technique used for comparison of two beds indicated that minimum score of pack bed absorber are 0.37 while the minimum score of fluidized bed adsorber are 0.5. It indicated when the adsorbent particles are smaller, fluidized bed adsorber are more suitable to use. In addition, using MCDA technique indicated that annular fluidized bed adsorber could considered as an alternative of fixed beds adsorber.

  6. Communications, Navigation, and Network Reconfigurable Test-bed Flight Hardware Compatibility Test S

    Science.gov (United States)

    2010-01-01

    Communications, Navigation, and Network Reconfigurable Test-bed Flight Hardware Compatibility Test Sets and Networks Integration Management Office Testing for the Tracking and Data Relay Satellite System

  7. Simulated moving bed system for CO.sub.2 separation, and method of same

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Jeannine Elizabeth; Copeland, Robert James; Lind, Jeff; Leta, Daniel P.; McCall, Patrick P.

    2016-09-20

    A system and method for separating and/or purification of CO.sub.2 gas from a CO.sub.2 feed stream is described. The system and method include a plurality of fixed sorbent beds, adsorption zones and desorption zones, where the sorbent beds are connected via valve and lines to create a simulated moving bed system, where the sorbent beds move from one adsorption position to another adsorption position, and then into one regeneration position to another regeneration position, and optionally back to an adsorption position. The system and method operate by concentration swing adsorption/desorption and by adsorptive/desorptive displacement.

  8. Bathing a patient in bed

    Science.gov (United States)

    Bed bath; Sponge bath ... Some patients cannot safely leave their beds to bathe. For these people, daily bed baths can help keep their skin healthy, control odor, and increase comfort. If moving the ...

  9. Quantified and applied sea-bed dynamics of the Netherlands Continental Shelf and the Wadden Sea

    NARCIS (Netherlands)

    van Dijk, T.A.G.P.; Kleuskens, M.H.P.; Dorst, L.L.; Van der Tak, C.; Doornenbal, P.J.; Van der Spek, A.J.F.; Hoogendoorn, R.M.; Rodriguez Aguilera, D.; Menninga, P.J.; Noorlandt, R.P.

    2012-01-01

    Sedimentary coasts and shallow-sea beds may be dynamic. The large-scaled spatial variation in these dynamics and the smaller-scaled behaviour of individual marine bedforms are largely unknown. Sea-bed dynamics are relevant for the safety of shipping, and therefore for monitoring strategies, and for

  10. Bed rest decreases mechanically induced myofiber wounding and consequent wound-mediated FGF release.

    Science.gov (United States)

    Clarke, M S; Bamman, M M; Feeback, D L

    1998-08-01

    Using a terrestrial model of spaceflight (i.e., bed rest), we investigated the amount of myofiber wounding and fibroblast growth factor (FGF) release that occurs during unloading. Myofiber wounding was determined by serum levels of the creatine kinase MM (CKMM) isoform before and after bed rest. Serum levels of both acidic FGF (aFGF) and basic FGF were also determined. A second group of subjects was treated in an identical fashion except that they underwent a resistive exercise program during bed rest. Bed rest alone caused significant (P size. In contrast, bed rest plus resistive exercise resulted in significant (P < 0.05; n = 7) increases in post-bed-rest serum levels of both CKMM and aFGF, which were paralleled by inhibition of the atrophic response. These results suggest that mechanically induced, myofiber wound-mediated FGF release may play an important role in the etiology of unloading-induced skeletal muscle atrophy. PMID:9688737

  11. Peach and apricot stone combustion in a bubbling fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Kaynak, B.; Atimtay, Aysel T. [Department of Environmental Engineering, Middle East Technical University, Ankara 06531 (Turkey); Topal, H. [Department of Mechanical Engineering, Engineering and Architecture Faculty, Gazi University, Ankara 06570 (Turkey)

    2005-07-25

    In this study, a bubbling fluidized bed combustor (BFBC) of 102 mm inside diameter and 900 mm height was used to investigate the combustion characteristics of peach and apricot stones produced as a waste from the fruit juice industry. A lignite coal was also burned in the same combustor. The combustion characteristics of the wastes were compared with that of a lignite coal that is most widely used in Turkey. On-line concentrations of O{sub 2}, CO, CO{sub 2}, SO{sub 2}, NO{sub X} and total hydrocarbons (C{sub m}H{sub n}) were measured in the flue gas during combustion experiments. By changing the operating parameters (excess air ratio, fluidization velocity, and fuel feed rate), the variation of emissions of various pollutants was studied. Temperature distribution along the bed was measured with thermocouples. During the combustion tests, it was observed that the volatile matter from peach and apricot stones quickly volatilizes and mostly burn in the freeboard. The temperature profiles along the bed and the freeboard also confirmed this phenomenon. It was found that as the volatile matter of fruit stones increases, the combustion takes place more in the freeboard region. The results of this study have shown that the combustion efficiencies ranged between 98.8% and 99.1% for coal, 96.0% and 97.5% for peach stone and 93.4% and 96.3% for apricot stones. The coal has zero CO emission, but biomass fuels have very high CO emission which indicates that a secondary air addition is required for the system. SO{sub 2} emission of the coal is around 2400-2800 mg/Nm{sup 3}, whereas the biomass fuels have zero SO{sub 2} emission. NO{sub x} emissions are all below the limits set by the Turkish Air Quality Control Regulation of 1986 (TAQCR) for all tests. As the results of combustion of two biomass fuels are compared with each other, peach stones gave lower CO and NO{sub x} emissions but the SO{sub 2} emissions are a little higher than for apricot stones. These results suggest that

  12. Application of Moving Bed Biofilm Process for Biological Organics and Nutrients Removal from Municipal Wastewater

    OpenAIRE

    M. Kermani; B BINA; Haji Movahedian; Amin, M. M.; M. Nikaein

    2008-01-01

    In this study, experiments have been conducted to evaluate the organics and nutrients removal from synthetic wastewater by a laboratory scale moving bed biofilm process. For nutrients removal, moving bed biofilm process has been applied in series with anaerobic, anoxic and aerobic units in four separate reactors. Moving bed biofilm reactors were operated continuously at different loading rates of nitrogen and Phosphorus. During optimum conditions, close to complete nitrification with average ...

  13. Acoustic observations of near-bed sediment concentration and flux statistics above migrating sand dunes

    Science.gov (United States)

    Wilson, G. W.; Hay, A. E.

    2016-06-01

    A coherent Doppler profiler was used to measure coincident time series of velocity (u,w), sediment mass concentration (c), and sediment grain size (d), above mobile sand dunes in unidirectional flow (˜1 m/s, ˜1 m water depth). The measurements are used to extract statistical distributions of sediment concentration and flux just above the bed. Observed mass fluxes (uc,wc) were well fit by quasi-exponential distributions, at all positions along the dune profile, similar to previous observations of single-particle momenta for bed load over flat beds. Observed concentrations of moving particles were well fit by negative-binomial distributions, also similar to previous observations over flat beds. These probability distributions relate to two recent stochastic theories, previously derived and verified for uniform flow over flat beds. It is hypothesized that these theories may also be used as a local approximation in natural-scale flows with bed forms.

  14. Pressure distension in leg vessels as influenced by prolonged bed rest and a pressure habituation regimen.

    Science.gov (United States)

    Eiken, Ola; Mekjavic, Igor B; Kounalakis, Stylianos N; Kölegård, Roger

    2016-06-15

    Bed rest increases pressure distension in arteries, arterioles, and veins of the leg. We hypothesized that bed-rest-induced deconditioning of leg vessels is governed by the removal of the local increments in transmural pressure induced by assuming erect posture and, therefore, can be counteracted by intermittently increasing local transmural pressure during the bed rest. Ten men underwent 5 wk of horizontal bed rest. A subatmospheric pressure (-90 mmHg) was intermittently applied to one lower leg [pressure habituation (PH) leg]. Vascular pressure distension was investigated before and after the bed rest, both in the PH and control (CN) leg by increasing local distending pressure, stepwise up to +200 mmHg. Vessel diameter and blood flow were measured in the posterior tibial artery and vessel diameter in the posterior tibial vein. In the CN leg, bed rest led to 5-fold and 2.7-fold increments (P pressure-distension and flow responses, respectively, and to a 2-fold increase in tibial vein pressure distension. In the PH leg, arterial pressure-distension and flow responses were unaffected by bed rest, whereas bed rest led to a 1.5-fold increase in venous pressure distension. It thus appears that bed-rest-induced deconditioning of leg arteries, arterioles, and veins is caused by removal of gravity-dependent local pressure loads and may be abolished or alleviated by a local pressure-habituation regimen.

  15. Filter bed systems treating domestic wastewater in the Nordic countries - Performance and reuse of filter media

    OpenAIRE

    Jenssen, Petter D.; Krogstad, T.; Paruch, A.M.; Mæhlum, Trond; Adam, K.; Arias, Carlos Alberto; Heistad, A.; Jonsson, L.; Hellström, D; Brix, Hans; Yli-Halla, M.; Vråle, L.; Valve, M.

    2010-01-01

    Nine filter beds have been constructed in the Nordic countries, Denmark, Finland, Norway and Sweden. Filter beds consist of a septic tank followed by an aerobic pre-treatment biofilter and a subsequent saturated flow grass-covered filter. Thus, filter beds are similar to subsurface flow constructed wetlands with pre-treatment biofilters, but do not have wetland plants with roots submerged into the saturated filter. All saturated filters contain Filtralite®P, a light-weight expanded clay aggre...

  16. Reducing Respiratory Health Risks to Horses and Workers: A Comparison of Two Stall Bedding Materials

    Directory of Open Access Journals (Sweden)

    Markku Saastamoinen

    2015-10-01

    Full Text Available Stable air quality and the choice of bedding material are an important health issue both in horses and people working or visiting horse stables. Risks of impaired respiratory health are those that can especially be avoided by improving air quality in the stable. The choice of bedding material is particularly important in cold climate conditions; where horses are kept most of the day and year indoors throughout their life. This study examined the effect of two bedding materials; wood shavings and peat; on stable air quality and health of horses. Ammonia and dust levels were also measured to assess conditions in the stable. Ammonia was not detected or was at very low levels (<0.25 ppm in the boxes in which peat was used as bedding; but its concentration was clearly higher (1.5–7.0 ppm in stalls with wood shavings as bedding. Personal measurements of workers revealed quite high ammonia exposure (5.9 ppm8h in the boxes in which wood shavings were used; but no exposure was Animals 2015, 5 966 observed in stalls bedded with peat. The respiratory symptoms in horses increased regardless of the bedding material at the beginning of the study. The health status of the horses in the peat bedding group returned to the initial level in the end of the trial but horses bedded with wood shavings continued to be symptomatic. The hooves of the horses with peat bedding had a better moisture content than those of the horses bedded with wood shavings. The results suggest that peat is a better bedding material for horses than wood shavings regarding the health of both horses and stable workers.

  17. The role of bedding in the evolution of meso- and microstructural fabrics in fault zones

    Science.gov (United States)

    Ishii, Eiichi

    2016-08-01

    To investigate the role of bedding in the evolution of meso- and microstructural fabrics in fault zones, detailed microscopic, mineralogical, and geochemical analyses were conducted on bedding-oblique and bedding-parallel faults that cut a folded Neogene siliceous mudstone that contains opal-CT, smectite, and illite. An analysis of asymmetric structures in the fault gouges indicates that the secondary fractures associated with each fault exhibit contrasting characteristics: those of the bedding-oblique fault are R1 shears, whereas those of the bedding-parallel fault are reactivated S foliation. The bedding-oblique fault shows the pervasive development of S foliation, lacks opal-CT, and has low SiO2/TiO2 ratios only in gouge, whereas the bedding-parallel fault exhibits these characteristics in both gouge and wall rocks. The development of S foliation and the lack of silica can result from local ductile deformation involving the sliding of phyllosilicates, coupled with pressure solution of opal-CT. Although such deformation can occur in gouge, the above results indicate that it may occur preferentially along bedding planes, preceding the formation of a gouge/slip surface. Thus, in sedimentary rocks that contain phyllosilicates and soluble minerals, bedding can influence the rheological evolution of meso- and microstructural fabrics in fault zones.

  18. Comparative study of hydrodynamic behavior of liquid expanded bed adsorption: mathematical and short-cut methods

    Directory of Open Access Journals (Sweden)

    M. Jahanshahi

    2009-06-01

    Full Text Available Liquid fluidized/expanded bed adsorption (LF/EBA is a novel chromatography technique for capturing target biomolecules directly from crude feedstock in downstream processing. To widely extend the LF/EBA technology in biological industries, a better understanding of the expanded-bed behavior is necessary to maximize its efficient applications. In this study, streamline adsorbent was loaded into the column and the bed was subjected to physical and hydrodynamical experiments. Hydrodynamic characteristics of the bed (e.g., Daxl and Bo with different settled bed height (SBH=5,6,7,8,9,10,11,12cm along with a variety of column diameters (1,1.6,2.5 cm have been investigated based on exact mathematical as well as approximate short-cut methods. It was found that the increasing column diameter promoted bed mixing, which was undesirable, and the optimal values for the bed expansion and SBH based on minimal liquid mixing were 80%-130% and 8-10 cm, respectively. However, exploiting the short-cut method for the bed hydrodynamic assessments also demonstrated results as good as the mathematical method. Hydrodynamic behavior of liquid fluidized bed adsorption and the generic application of the short-cut method and its potential as a simple method for study of hydrodynamic performance is discussed.

  19. Study of Solids and Gas Distribution in Spouted Bed Operated In Stable and Unstable Conditions

    Directory of Open Access Journals (Sweden)

    Alwan, G. M.,

    2014-02-01

    Full Text Available A spouted bed is a special case of fluidization. It is an effective means of contacting gas with coarse solid particles. Spouted beds should be designed and operated to overcome performance instability and improves the uniform distribution of particles. Steady-state measurements were carried out in the 0.152 m ID cylindrical spouted bed made of Plexiglas that used 60° conical shape spout-air bed. The evaluation of solid and gas holdup in the two regions of spouted bed at stable and an unstable condition was performed using optical probe. The comparison of the radial profiles at the two conditions showed that the variation was in the spout region. The annulus region had similar profiles in both the condition as it acts as a loose packed bed, moving slowly downward. Stable bed was obtained at low gas velocity of 0.74 m/s and instability of spouting was observed at high gas velocity of 1.4 m/s. The beads can fluidize homogenously at stable conditions, while pulsation of the bed was appeared at unstable spout. Different flow regimes and characteristics can be obtained with minor variations in geometry or operating conditions.

  20. Kinetics studies of uranium sorption by powdered corn cob in batch and fixed bed system.

    Science.gov (United States)

    Mahmoud, Mohamed A

    2016-01-01

    Sorption of uranium (VI) from aqueous solution onto powdered corn cob has been carried out using batch and fixed-bed technique. The experimental results in batch technique were fitted well with pseudo second-order kinetics model. In the fixed bed technique, Thomas and Bohart-Adams models were evaluated by linear regression analysis for U(VI) uptake in different flow rates, bed heights and initial concentrations. The column experimental data were fitted well with Thomas mode (r (2) = 0.999), but the Bohart-Adams model (r (2) = 0.911), predicted poor performance of fixed-bed column. PMID:26843973

  1. Enhanced stability of hillslopes and channel beds to mass failure

    Science.gov (United States)

    Prancevic, Jeff; Lamb, Michael; Palucis, Marisa; Venditti, Jeremy

    2016-04-01

    The stability of inclined, unconsolidated sediments subjected to groundwater flow on hillslopes and steep channel beds is important for both landscape evolution and natural hazards. Force-balance models have been used for seven decades to predict the stability of slopes, but they generally underpredict the degree of saturation required to destabilize the sediment. Researchers often appeal to heightened stabilizing forces from root and mineral cohesion, and friction acting on the margins of the failure to explain this underprediction. Surprisingly, infinite-slope stability models in their simplest form have never been tested under controlled laboratory conditions. To address this gap in data, we perform a set of controlled laboratory experiments with slope-parallel seepage in the simplest possible configuration. We performed 47 experiments in a 5 m laboratory flume with 4 grain sizes (D50 = 0.7, 2, 5, and 15 mm) and a wide range in bed angles (20° to 43°), spanning both Darcian and turbulent subsurface flow regimes. Our experiments show that granular slopes were more stable than predicted by simple force balance models in experiments that lack root or mineral cohesion. Despite the smooth plastic walls and the long aspect ratio of our flume, we calculate wall and toe friction to be important. Including these additional resistance terms in the model reduces the model misfit with our experimental results. However, there is considerable remaining misfit (up to 50% underestimation of the saturation level required for failure). We investigate two explanations of this heightened stability: 1) standard frictional resistance terms are underestimated, and 2) seepage stresses are overestimated. Both explanations require that we modify the models used to predict slope stability.

  2. The JET ICRF antennae systems: Description and test bed results

    International Nuclear Information System (INIS)

    The main design features and test results of the prototype antennae systems for ICRF heating of JET are described. These have integral side protection, thick tilted screens, monopole or quadrupole central conductors, and are each fed by two co-axial lines of diameter varying from 100 to 230mm. The vacuum window is of a double, vacuum brazed alumina construction. The main components have been tested on the JET RF Test Bed at Fontenay-aux-Roses to maximum voltage (50kV) and current (1500 Amps). Apart from a narrow forbidden band at a low voltage due to the onset of multipactor arcs, these systems have largely met the required specifications

  3. Effectiveness of a Sugar-Yeast Monitor and a Chemical Lure for Detecting Bed Bugs.

    Science.gov (United States)

    Singh, Narinderpal; Wang, Changlu; Cooper, Richard

    2015-06-01

    Effective bed bug (Cimex lectularius L.) monitors have been actively sought in the past few years to help detect bed bugs and measure the effectiveness of treatments. Most of the available active monitors are either expensive or ineffective. We designed a simple and affordable active bed bug monitor that uses sugar-yeast fermentation and an experimental chemical lure to detect bed bugs. The sugar-yeast mixture released carbon dioxide at a similar rate (average 405.1 ml/min) as dry ice (average 397.0 ml/min) during the first 8 h after activation. In naturally infested apartments, the sugar-yeast monitor containing an experimental chemical lure (nonanal, L-lactic acid, 1-octen-3-ol, and spearmint oil) was equally effective as the dry ice monitor containing the same lure in trapping bed bugs. Placing one sugar-yeast monitor per apartment for 1-d was equally effective as 11-d placement of 6-18 Climbup insect interceptors (a commonly used bed bug monitor) under furniture legs for trapping bed bugs. When carbon dioxide was present, pair-wise comparisons showed the experimental lure increased trap catch by 7.2 times. This sugar-yeast monitor with a chemical lure is an affordable and effective tool for monitoring bed bugs. This monitor is especially useful for monitoring bed bugs where a human host is not present. PMID:26470258

  4. Orthostatic hypotension in patients, bed rest subjects, and astronauts

    Science.gov (United States)

    Lathers, C. M.; Charles, J. B.

    1994-01-01

    Orthostatic hypotension after even short space flights has affected a significant number of astronauts. Given the need for astronauts to function at a high level of efficiency during and after their return from space, the application of pharmacologic and other treatments is strongly indicated. This report addresses the clinical problem of orthostatic hypotension and its treatments to ascertain whether pharmacologic or physiologic treatment may be useful in the prevention of orthostatic hypotension associated with space flight. Treatment of orthostatic hypotension in patients now includes increasing intravascular volume with high sodium intake and mineralocorticoids, or increasing vascular resistance through the use of drugs to stimulate alpha or block beta vascular receptors. Earlier treatment used oral sympathomimetic ephedrine hydrochloride alone or with "head-up" bed rest. Then long-acting adrenocortical steroid desoxycorticosterone preparations with high-salt diets were used to expand volume. Fludrocortisone was shown to prevent the orthostatic drop in blood pressure. The combination of the sympathomimetic amine hydroxyamphetamine and a monoamine oxidase inhibitor tranylcypromine has been used, as has indomethacin alone. Davies et al. used mineralocorticoids at low doses concomitantly with alpha-agonists to increase vasoconstrictor action. Schirger et al used tranylcypromine and methylphenidate with or without a Jobst elastic leotard garment or the alpha-adrenergic agonist midodrine (which stimulates both arterial and venous systems without direct central nervous system or cardiac effects). Vernikos et al established that the combination of fludrocortisone, dextroamphetamine, and atropine exhibited a beneficial effect on orthostatic hypotension induced by 7-day 6 degrees head-down bed rest (a model used to simulate the weightlessness of space flight). Thus, there are numerous drugs that, in combination with mechanical techniques, including lower body negative

  5. Investigation of Adsorbed Gases Content in Coal Beds in Bosnia and Herzegovina

    OpenAIRE

    Sadadinovic, J.; Mičević, S.

    2008-01-01

    Investigation of the gas fraction in coal beds in Bosnia & Herzegovina has been performed systematically since 1988. Gas in coal beds can be present in free or adsorbed form, and dissolved in water. Methods of investigation are based on the direct approach, according to which the gas fraction is determined in the undisturbed coal bed.The quantity of the adsorbed and free gas in the coal bed is directly proportional to the gas pressure. Dependence is hyperbolic. The quantity of the free gas in...

  6. Thin bed responses and correction methods for cased hole density logging

    Institute of Scientific and Technical Information of China (English)

    Wu Wensheng; Zhang Yuling

    2008-01-01

    The study of the thin bed responses and correction methods in cased hole density logging can provide a theoretical basis for research to improve data processing methods. By using the Monte Carlo program MCNP, the change of detector count from thin beds with the vertical depth was calculated at different casing thicknesses. The calculation showed that with the low density thin bed moving upward,detector count first increased to a maximum then decreased. The responses of a thin bed with a high density were opposite to those of a thin bed with a low density. The change curve was symmetrical, and the maximums or minimums appeared at the midpoint between the detector and source. Besides, detector count increased with increasing thin bed thickness. At a specific thin bed thickness, further increase of thin bed thickness resulted in a slow increase of detector count then the count rate leveled off. In actual logging, the influence of adjacent formations on density log measurements can be ignored. Finally, based on numerical simulation correction methods for the dual influence of casing and thin beds are discussed.

  7. Steam gasification of various feedstocks at a dual fluidised bed gasifier: Impacts of operation conditions and bed materials

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, Christoph; Koppatz, Stefan; Hofbauer, Hermann [Vienna University of Technology, Institute of Chemical Engineering, Vienna (Austria)

    2011-03-15

    Gasification of biomass is an attractive technology for combined heat and power production as well as for synthesis processes such as production of liquid and gaseous biofuels. Dual fluidised bed (DFB) technology offers the advantage of a nearly nitrogen-free product gas mainly consisting of H{sub 2}, CO, CO{sub 2} and CH{sub 4}. The DFB steam gasification process has been developed at Vienna University of Technology over the last 15 years using cold flow models, laboratory units, mathematical modelling and simulation. The main findings of the experimental work at a 100-kW pilot scale unit are presented. Different fuels (wood pellets, wood chips, lignite, coal, etc.) and different bed materials (natural minerals such as olivine, limestones, calcites, etc. as well as modified olivines) have been tested and the influence on tar content as well as gas composition was measured and compared among the different components. Moreover, the influence of operating parameters such as fuel moisture content, steam/fuel ratio and gasification temperature on the product gas has been investigated. DFB steam gasification of solid biomass coupled with CO{sub 2} capture, the so-called absorption enhanced reforming (AER) process, is highlighted. The experiments in pilot scale led to commercial realisation of this technology in demonstration scale. Summarising, the DFB system offers excellent fuel flexibility to be used in advanced power cycles as well as in polygeneration applications. (orig.)

  8. Nonlinear dynamics and control of a recycle fixed bed reactor

    OpenAIRE

    Recke, Bodil; Jørgensen, Sten Bay

    1997-01-01

    The purpose of this paper is twofold. Primarily to describe the dynamic behaviour that can be observed in a fixed bed reactor with recycle of unconverted reactant. Secondly to describe the possibilities of model reduction in order to facilitate control design. Reactant recycle has been shown to introduce periodic solution to the fixed bed reactor, a phenomenon which is not seen for the system without the recycle, at least not within the Peclet number range investigated in the present work. Th...

  9. Sediment concentration profiles in bed-near-bed layers under unsteady flow and sediment conditions : a CT-Scanned flume investigation

    Science.gov (United States)

    Leclair, Suzanne; Long, Bernard

    2015-04-01

    This paper presents a case study from a CT-scan flume experiment on the variation in sediment transport (concentration) under transitional, initially high-regime (but decreasing), sub-critical flow with bed erosion or no net aggradation. The objective is to better understand sediment transport during unsteady flows such as during a wining flood. In particular, the effect of mud-aggregate transport on sediment concentration in the bed-near-bed continuum was addressed. CT-scans were taken during sediment transport, with plane beds or dunes being the bed state. The density material (water and/or sediment) in over 105 volumes (voxels, each approximately equivalent to a grain of 0.8 mm) were analysed. Computed Tomography technology provides high-resolution results, both in time and space, and allows recognition of subtle changes in the shape of relative sediment concentration profile with bed states. The migration and attrition of mud aggregates in this experiment increased the mean volume fraction sediment concentration in the bed-near-bed layer (lower 5% of the flow) by a factor of about 2, from an inital value of 0.12 up to 0.25, and back to 0.13 when the supply ended. Also, the presence of mud-aggregates in the preserved deposits (transported as bedload) increases bed porosity. This case study demonstrates the great potential of Computed Tomography in process-oriented, experimental sedimentology. The community would benefit from more collaborative research using this technology, including data sharing as suggested by initiatives such as the Sediment Experimentalists Network (http://workspace.earthcube.org/sen)

  10. Fate of xenobiotic compounds and plants activity in reed bed sludge treatment

    DEFF Research Database (Denmark)

    Chen, Xijuan; Pauli, Udo; Rehfus, Stefan;

    Sludge reed beds have been used for dewatering (draining and evapotranspiration) and mineralisation of sludge in Europe since 1988. Although reed beds are considered as a low cost and low contamination method in reducing volume, breaking down organic matter and increasing the density of sludge....... A mass balance calculating showed that

  11. Catalytic Pyrolysis of Oak via Pyroprobe and Bench Scale, Packed Bed Pyrolysis Reactors

    Science.gov (United States)

    The pyrolytic conversion of oak sawdust at 500°C in flowing He over eight proprietary catalysts is described and compared to the control bed material, quartz sand. The reactions were conducted and compared in two reactors, an analytical, ug-scale pyroprobe reactor and a bench, g-scale packed bed re...

  12. Multiple Intelligence and Digital Learning Awareness of Prospective B.Ed Teachers

    Science.gov (United States)

    Gracious, F. L. Antony; Shyla, F. L. Jasmine Anne

    2012-01-01

    The present study Multiple Intelligence and Digital Learning Awareness of prospective B.Ed teachers was probed to find the relationship between Multiple Intelligence and Digital Learning Awareness of Prospective B.Ed Teachers. Data for the study were collected using self made Multiple Intelligence Inventory and Digital Learning Awareness Scale.…

  13. Spectral Characteristics of Common Reed Beds: Studies on Spatial and Temporal Variability

    Directory of Open Access Journals (Sweden)

    Jyrki Tuominen

    2016-02-01

    Full Text Available Reed beds are the second largest producer of biomass in Olkiluoto Island. Quantitative information on the extent and amount of reed stands is an integral part of the biosphere assessment related to long-term safety analysis of nuclear fuel repository site currently under construction. The major challenge in reed bed mapping is discrimination between reed and other green vegetation. Spectral field measurements were used to study the temporal and spatial variability of spectral characteristics of reed beds. Feasibility of discriminating reed beds from other vegetation based on hyperspectral measurements was studied as well. Results indicate that there is large temporal variation of reed bed spectra and the optimal time for data acquisition differs for old and new reed bed types. Comparing spectral characteristics of the reed bed and meadow classes in a local neighborhood indicated that the classes have high within-class spectral variability and similar mean spectra, however, 10 out of 11 targets had lower angle to the mean spectrum of the corresponding class than that of the other class when Spectral Angle Mapper (SAM was used. Comparing the spectral characteristics of reed beds at four test sites within the Olkiluoto Island indicated that while some of the sites had similar spectra, the difference between others was remarkable. This is partly explained by different density and height of dead and live reed stems at the four sites.

  14. Water column and bed-sediment core samples collected from Brownlee Reservoir near Oxbow, Oregon, 2012

    Science.gov (United States)

    Fosness, Ryan L.; Naymik, Jesse; Hopkins, Candice B.; DeWild, John F.

    2013-01-01

    The U.S. Geological Survey, in cooperation with Idaho Power Company, collected water-column and bed-sediment core samples from eight sites in Brownlee Reservoir near Oxbow, Oregon, during May 5–7, 2012. Water-column and bed-sediment core samples were collected at each of the eight sites and analyzed for total mercury and methylmercury. Additional bed-sediment core samples, collected from three of the eight sites, were analyzed for pesticides and other organic compounds, trace metals, and physical characteristics, such as particle size. Total mercury and methylmercury were detected in each of the water column and bed-sediment core samples. Only 17 of the 417 unique pesticide and organic compounds were detected in bed-sediment core samples. Concentrations of most organic wastewater compounds detected in bed sediment were less than the reporting level. Trace metals detected were greater than the reporting level in all the bed-sediment core samples submitted for analysis. The particle size distribution of bed-sediment core samples was predominantly clay mixed with silt.

  15. Fluidisation and dispersion behaviour of small high density pellicular expanded bed adsorbents

    DEFF Research Database (Denmark)

    Theodossiou, Irini; Elsner, H.D.; Thomas, Owen R. T.;

    2002-01-01

    The fluidisation and dispersion properties of various agarose-based expanded bed matrices-small high density stainless steel cored prototypes and standard commercial types-were studied in I-cm diameter expanded bed contactors in which fluid entering the column base is locally stirred. In all cases...

  16. Flow velocities and bed shear stresses in a stone cover under an oscillatory flow

    DEFF Research Database (Denmark)

    Stenanato, F.; Nielsen, Anders Wedel; Sumer, B. Mutlu;

    2010-01-01

    I order to get a better understanding of the interaction between the wave-induced, near-bed oscillatory flow, the stome cover and the sea bed, physical model tests were carried out. The tests were conducted in an oscillating water tunnel. The bottom of the tunnes was covered by one, two and three...

  17. Feather bedding and childhood asthma associated with house dust mite sensitisation : a randomised controlled trial

    NARCIS (Netherlands)

    Glasgow, Nicholas J.; Ponsonby, Anne-Louise; Kemp, Andrew; Tovey, Euan; van Asperen, Peter; McKay, Karen; Forbes, Samantha

    2011-01-01

    Introduction Observational studies report inverse associations between the use of feather upper bedding (pillow and/or quilt) and asthma symptoms but there is no randomised controlled trial (RCT) evidence assessing the role of feather upper bedding as a secondary prevention measure. Objective To det

  18. The expression of the jigging bed porosity and its realizing of the computer detection system

    Institute of Scientific and Technical Information of China (English)

    DU Chang-long; LIN Ming-xing; YUAN Hui

    2001-01-01

    This peper proposes the expression of the jigging bed porosity based on the jumping height of the jigging bed and water wave. This kind of expression can help to realize the jigging process automation and intelligence. The computer detection system is also developed.

  19. Genome assembly and geospatial phylogenomics of the bed bug Cimex lectularius

    NARCIS (Netherlands)

    Rosenfeld, Jeffrey A.; Reeves, Darryl; Brugler, Mercer R.; Narechania, Apurva; Simon, Sabrina; Durrett, Russell; Foox, Jonathan; Shianna, Kevin; Schatz, Michael C.; Gandara, Jorge; Afshinnekoo, Ebrahim; Lam, Ernest T.; Hastie, Alex R.; Chan, Saki; Cao, Han; Saghbini, Michael; Kentsis, Alex; Planet, Paul J.; Kholodovych, Vladyslav; Tessler, Michael; Baker, Richard; DeSalle, Rob; Sorkin, Louis N.; Kolokotronis, Sergios Orestis; Siddall, Mark E.; Amato, George; Mason, Christopher E.

    2016-01-01

    The common bed bug (Cimex lectularius) has been a persistent pest of humans for thousands of years, yet the genetic basis of the bed bug's basic biology and adaptation to dense human environments is largely unknown. Here we report the assembly, annotation and phylogenetic mapping of the 697.9-Mb

  20. Vision in the common bed bug Cimex lectularius L. (Hemiptera: Cimicidae): eye morphology and spectral sensitivity

    Science.gov (United States)

    Bed bugs as pests of public health importance recently experienced a resurgence in populations throughout the U.S. and other countries. Consequently, recent research efforts have focused on improving understanding of bed bug physiology and behavior to improve management. While few studies have inves...

  1. Fibroblast Growth Factor-23 in Bed Rest and Spaceflight

    Science.gov (United States)

    Bokhari, R.; Zwart, S. R; Fields, E.; Heer, M.; Sibonga, J.; Smith, S. M.

    2014-01-01

    Many nutritional factors influence bone, from the basics of calcium and vitamin D, to factors which influence bone through acid/base balance, including protein, sodium, and more. Fibroblast growth factor 23 (FGF23) is a recently identified factor, secreted from osteocytes, which is involved in classic (albeit complex) feedback loops controlling phosphorus homeostasis through both vitamin D and parathyroid hormone (PTH) (1, 2). As osteocytes are gravity sensing cells, it is important to determine if there are changes in FGF23 during spaceflight. In extreme cases, such as chronic kidney disease, FGF23 levels are highly elevated. FGF23 imbalances, secondary to dietary influences, may contribute to skeletal demineralization and kidney stone risk during spaceflight. Presented with an imbalanced dietary phosphorus to calcium ratio, increased secretion of FGF23 will inhibit renal phosphorus reabsorption, resulting in increased excretion and reduced circulating phosphorus. Increased intake and excretion of phosphorus is associated with increased kidney stone risk in both the terrestrial and microgravity environments. Highly processed foods and carbonated beverages are associated with higher phosphorus content. Ideally, the dietary calcium to phosphorus ratio should be at minimum 1:1. Nutritional requirements for spaceflight suggest that this ratio not be less than 0.67 (3), while the International Space Station (ISS) menu provides 1020 mg Ca and 1856 mg P, for a ratio of 0.55 (3). Subjects in NASA's bed rest studies, by design, have consumed intake ratios much closer to 1.0 (4). FGF23 also has an inhibitory influence on PTH secretion and 1(alpha)-hydroxylase, both of which are required for activating vitamin D with the conversion of 25-hydroxyvitamin D to 1,25-dihydroxyvitamin D. Decreased 1,25-dihydroxyvitamin D will result in decreased intestinal phosphorus absorption, and increased urinary phosphorus excretion (via decreased renal reabsorption). Should a decrease in 1

  2. Fluidized bed spray granulation: analysis of heat and mass transfers and dynamic particle populations

    Directory of Open Access Journals (Sweden)

    S. Heinrich

    2005-06-01

    Full Text Available A model was developed taking into consideration the heat and mass transfer processes in liquid-sprayed fluidized beds. Such fluidized beds (FB are used for granulation, coating and agglomeration. Conclusions are drawn on the relevance of particle dispersion, spraying and drying to temperature and concentrations distributions. In extension, the model was coupled with a population balance model to describe the particle size distribution and the seeds formation for continuous external FBSG (fluidized bed spray granulation with non-classifying product discharge and a screening and milling unit in the seeds recycle. The effects of seeds formation on the stability of the process is discussed.

  3. Development and Experiments of a Test-Bed for Wheel-Soil Interaction of Lunar Rover

    Science.gov (United States)

    Tao, Jianguo; Ding, Liang; Quan, Qiquan; Gao, Haibo

    2012-07-01

    Wheel-soil interaction of lunar exploring rover plays a critical role in rover mechanical design, control and simulation. For presenting and validating effective terramechanics models, as well as evaluating rover wheel performance, a set of wheel-soil interaction test- bed was developed. The test-bed can control the wheel rolling or steering movement at different slippage rates and different speeds, and through a variety of sensors to acquire the measured values of mechanical properties of wheel-soil interaction such as drawbar pull, side force, wheel sinkage displacement, steering torque. In this paper, some characteristics of the test-bed are described, and some experimental works in a rigid rover wheel design and wheel-soil interaction modeling by means of this test-bed are summarized. Experimental results show that the test-bed can accurately and efficiently test wheel-soil interaction for various wheels and loose soil types.

  4. Major salt beds of the Palo Duro and Dalhart Basins, Texas

    International Nuclear Information System (INIS)

    Major salt beds are defined as salt intervals at least 75 feet thick that contain no interbeds greater than 10 feet thick and include no more than 15 percent non-salt interbeds. Maps based on the interpretation of geophysical logs from hundreds of oil and gas exploration wells reveal seven major salt beds in the Palo Duro Basin and one major salt bed in the Dalhart Basin. The most extensive major salt beds are in the central and northern Palo Duro Basin, in the Upper San Andres Formation and the Lower San Andres Formation Units 4 and 5. Of these, the major salt bed within the Lower San Andres Formation Unit 4 is the most widespread and generally the thickest. 7 references, 15 figures, 2 tables

  5. Experiment and numerical simulation of water surface response to rise and depression of the sea bed

    International Nuclear Information System (INIS)

    Water surface response to rise and depression of the sea bed was investigated by a hydraulic experiment and a numerical model development based on a fully nonlinear boundary element method. First, it was found that initial water surface behavior is fairly coincident between the experimental and numerical results under the initial conditions of up-surge and down-surge. Secondly, by the experimental and the numerical results it was made clear that larger deformation speed of the sea bed, smaller sea bed deformation and smaller water depth of the sea movement cause larger response efficiency of water surface. (author)

  6. Caribbean mangroves and seagrass beds as diurnal feeding habitats for juvenile French grunts, Haemulon flavolineatum.

    NARCIS (Netherlands)

    Verwey, M.C.; Nagelkerken, I.; Wartenbergh, S.L.J.; Pen, I.R.; Velde, G. van der

    2006-01-01

    Abstract Caribbean seagrass beds are important feeding habitats for so-called nocturnally active zoobenthivorous fish, but the extent to which these fishes use mangroves and seagrass beds as feeding habitats during daytime remains unclear. We hypothesised three feeding strategies: (1) fishes feed o

  7. Caribbean mangroves and seagrass beds as daytime feeding habitats for juvenile French grunts, Haemulon flavolineatum

    NARCIS (Netherlands)

    Verweij, M.C.; Nagelkerken, I.; Wartenbergh, S.L.J.; Pen, I.R.; Van der Velde, G.

    2006-01-01

    Caribbean seagrass beds are important feeding habitats for so-called nocturnally active zoobenthivorous fish, but the extent to which these fishes use mangroves and seagrass beds as feeding habitats during daytime remains unclear. We hypothesised three feeding strategies: (1) fishes feed opportunist

  8. Mangroves and seagrass beds as diurnal feeding habitats for juvenile Haemulon flavolineatum

    NARCIS (Netherlands)

    Verweij, M.C.; Nagelkerken, I.; Wartenbergh, S.L.J.; Pen, I.R.; Velde, G. van der

    2007-01-01

    Caribbean seagrass beds supposedly are important feeding habitats for so-called nocturnally active zoobenthivorous fish, but the extent to which these fishes use mangroves and seagrass beds as feeding habitats during daytime remains unclear. Therefore, we studied daytime behavior of large juvenile (

  9. Evolution of bed form height and length during a discharge wave

    NARCIS (Netherlands)

    Warmink, J.J.; Schielen, R.M.J.; Dohmen-Janssen, C.M.; Lancker, van V.; Garlan, T.

    2013-01-01

    This research focusses on modeling the evolution of bed form during a discharge wave for application in operational flood forecasting. The objective of this research was to analyze and predict the bed form evolution during a discharge wave in a flume experiment. We analyzed the data of a flume exper

  10. Flow structure formation and evolution in circulating gas-fluidised beds

    NARCIS (Netherlands)

    Li, Jie; Kuipers, J.A.M.

    2004-01-01

    The occurrence of heterogeneous flow structures in gas-particle flows seriously affects the gas-solid contacting and transport processes in high-velocity gas-fluidized beds. Particles do not disperse uniformly in the flow but pass through the bed in a swarm of clusters. The so-called "core-annulus"

  11. Biometrics for Emotion Detection (BED): Exploring the combination of Speech and ECG

    NARCIS (Netherlands)

    Schut, Marleen H.; Tuinenbreijer, Kees; Broek, van den Egon L.; Westerink, Joyce H.D.M.; Kim, Jonghwa; Karjalainen, Pasi

    2010-01-01

    The paradigm Biometrics for Emotion Detection (BED) is introduced, which enables unobtrusive emotion recognition, taking into account varying environments. It uses the electrocardiogram (ECG) and speech, as a powerful but rarely used combination to unravel people’s emotions. BED was applied in two e

  12. Upper Cretaceous pelagic red beds,implications for paleoclimate and pale oc eanography

    Institute of Scientific and Technical Information of China (English)

    LubaJansa; O.Tuysuz; R.W.Scott

    2004-01-01

    Members of IGCP 463, Upper Cretaceous Oceanic Red Beds: Response to Ocean/Climate Global Change (CORBs) held their second workshop near the Black Sea in Bartin, Turkey. In addition to discussion of results and plans, the participants examined exposures of pelagic red beds in northern Turkev.

  13. Energy monitoring and analysis during deformation of bedded-sandstone: use of acoustic emission.

    Science.gov (United States)

    Wasantha, P L P; Ranjith, P G; Shao, S S

    2014-01-01

    This paper investigates the mechanical behaviour and energy releasing characteristics of bedded-sandstone with bedding layers in different orientations, under uniaxial compression. Cylindrical sandstone specimens (54 mm diameter and 108 mm height) with bedding layers inclined at angles of 10°, 20°, 35°, 55°, and 83° to the minor principal stress direction, were produced to perform a series of Uniaxial Compressive Strength (UCS) tests. One of the two identical sample sets was fully-saturated with water before testing and the other set was tested under dry conditions. An acoustic emission system was employed in all the testing to monitor the acoustic energy release during the whole deformation process of specimens. From the test results, the critical joint orientation was observed as 55° for both dry and saturated samples and the peak-strength losses due to water were 15.56%, 20.06%, 13.5%, 13.2%, and 13.52% for the bedding orientations 10°, 20°, 35°, 55°, and 83°, respectively. The failure mechanisms for the specimens with bedding layers in 10°, 20° orientations showed splitting type failure, while the specimens with bedding layers in 55°, 83° orientations were failed by sliding along a weaker bedding layer. The failure mechanism for the specimens with bedding layers in 35° orientation showed a mixed failure mode of both splitting and sliding types. Analysis of the acoustic energy, captured from the acoustic emission detection system, revealed that the acoustic energy release is considerably higher in dry specimens than that of the saturated specimens at any bedding orientation. In addition, higher energy release was observed for specimens with bedding layers oriented in shallow angles (which were undergoing splitting type failures), whereas specimens with steeply oriented bedding layers (which were undergoing sliding type failures) showed a comparatively less energy release under both dry and saturated conditions. Moreover, a considerable amount of

  14. Pebble-bed pebble motion: Simulation and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Joshua J. Cogliati; Abderrafi M. Ougouag

    2011-11-01

    Pebble bed reactors (PBR) have moving graphite fuel pebbles. This unique feature provides advantages, but also means that simulation of the reactor requires understanding the typical motion and location of the granular flow of pebbles. This report presents a method for simulation of motion of the pebbles in a PBR. A new mechanical motion simulator, PEBBLES, efficiently simulates the key elements of motion of the pebbles in a PBR. This model simulates gravitational force and contact forces including kinetic and true static friction. It's used for a variety of tasks including simulation of the effect of earthquakes on a PBR, calculation of packing fractions, Dancoff factors, pebble wear and the pebble force on the walls. The simulator includes a new differential static friction model for the varied geometries of PBRs. A new static friction benchmark was devised via analytically solving the mechanics equations to determine the minimum pebble-to-pebble friction and pebble-to-surface friction for a five pebble pyramid. This pyramid check as well as a comparison to the Janssen formula was used to test the new static friction equations. Because larger pebble bed simulations involve hundreds of thousands of pebbles and long periods of time, the PEBBLES code has been parallelized. PEBBLES runs on shared memory architectures and distributed memory architectures. For the shared memory architecture, the code uses a new O(n) lock-less parallel collision detection algorithm to determine which pebbles are likely to be in contact. The new collision detection algorithm improves on the traditional non-parallel O(n log(n)) collision detection algorithm. These features combine to form a fast parallel pebble motion simulation. The PEBBLES code provides new capabilities for understanding and optimizing PBRs. The PEBBLES code has provided the pebble motion data required to calculate the motion of pebbles during a simulated earthquake. The PEBBLES code provides the ability to

  15. Measurement of the thermal conductivity and heat transfer coefficient of a binary bed of beryllium pebbles

    Energy Technology Data Exchange (ETDEWEB)

    Donne, M.D.; Piazza, G. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer Neutronenphysik und Reaktortechnik; Goraieb, A.; Sordon, G.

    1998-01-01

    The four ITER partners propose to use binary beryllium pebble bed as neutron multiplier. Recently this solution has been adopted for the ITER blanket as well. In order to study the heat transfer in the blanket the effective thermal conductivity and the wall heat transfer coefficient of the bed have to be known. Therefore at Forschungszentrum Karlsruhe heat transfer experiments have been performed with a binary bed of beryllium pebbles and the results have been correlated expressing thermal conductivity and wall heat transfer coefficients as a function of temperature in the bed and of the difference between the thermal expansion of the bed and of that of the confinement walls. The comparison of the obtained correlations with the data available from the literature show a quite good agreement. (author)

  16. Implementation and full scale test of sand bed filter

    International Nuclear Information System (INIS)

    All French PWR's operating plants are now equipped with a containment postaccident decompression filtration system using a sand bed filter. The system also possesses a real time gamma spectrometry radioactivity monitor. First, the paper covers: the design and sizing requirements of the system resulting from a R and D program (PITEAS) carried out at the Cadarache Nuclear Studies Center jointly by Electricite de France and the French Atomic Energy Commission; the detailed description of the radioactivity monitor which would display the activity concentration for the main radioactive elements (iodine, caesium, etc) with a large range; the principles and the results of full scale tests carried out on a test loop (FUCHIA) with a representative geometry of the French plants. The aim was to know the operating limits of the system in two different kinds of tests; filtration efficiency tests with aerosols generated by means of plasma torches; thermohydraulic and thermic behaviour tests with residual power simulation by means of electrical heaters. The FUCHIA tests have definitively qualified the system showing global efficiencies of about 200 for the aerosols. In its present state the system is able to mitigate most cases of severe accident scenarios. Nevertheless, Electricite de France has decided to improve the ability of the system and to reduce the dose rate on site in still severer postaccident conditions. Therefore, the paper also covers: the design of the complementary radiological shieldings, for the 900 MW series and the first 1300 MW series these consist of glass fiber thermosetting resin containers filled with water at the right time, for all other series they consist of a concrete slab; the principle of the sand bed filter heat removal, after use the filter tank can be water sprinkled or cooled by a sufficient fresh air flow; the design of the hydrogen risk protection by preheating, this consists of heated air flow blown with a fixed fan and an electric heater

  17. Research into Biomass and Waste Gasification in Atmospheric Fluidized Bed

    Energy Technology Data Exchange (ETDEWEB)

    Skala, Zdenek; Ochrana, Ladislav; Lisy, Martin; Balas, Marek; Kohout, Premysl; Skoblja, Sergej

    2007-07-01

    Considerable attention is paid in the Czech Republic to renewable energy sources. The largest potential, out of them all, have biomass and waste. The aim therefore is to use them in CHP in smaller units (up to 5MWel). These are the subject of the research summarized in our article. The paper presents results of experimental research into gasification in a 100 kW AFB gasifier situated in Energy Institute, Faculty of Mechanical Engineering, Brno University of Technology, and fitted with gas cleaning equipment. Within the research, study was carried out into gas cleaning taking primary measures in the fluidized bed and using hot filter, metal-based catalytic filter, and wet scrubber. Descriptions and diagrams are given of the gasifier and new ways of cleaning. Results include: Impact of various fuels (farming and forest wastes and fast-growing woods and culm plants) on fuel gas quality. Individual kinds of biomass have very different thermal and physical properties; Efficiency of a variety of cleaning methods on content of dust and tars and comparison of these methods; and, Impact of gasifier process parameters on resultant gas quality. (auth)

  18. An assessment of biological processes close to the sea bed in a slope region and its significance to the assessment of sea bed disposal of radioactive waste

    International Nuclear Information System (INIS)

    Vertical profiles of planktonic and micronektonic biomass observed close to the sea bed along a transect running up the continental slope on the southern flank of the Porcupine Seabight (to the southwest of Ireland) showed that a doubling in biomass concentration occurs from 100 to 10m above the sea bed. Comparison with biomass concentrations at two deep water stations, one in the Seabight and the other in the Rockall Trough, showed that there was a consistent increase in standing crop close to the sea bed over the slope. Supplementary data were collected on the northern flank of the Seabight. Analysis of both taxonomic groups and individual species showed that some taxa were more abundant near the sea floor and extended their vertical ranges to greater depths over the slope than over deep water, other taxa were unaffected. The implications to the problem of assessing the safety of sea bed disposal of high level radioactive waste are summarised. (author)

  19. Moving bed biofilm reactor technology: process applications, design, and performance.

    Science.gov (United States)

    McQuarrie, James P; Boltz, Joshua P

    2011-06-01

    The moving bed biofilm reactor (MBBR) can operate as a 2- (anoxic) or 3-(aerobic) phase system with buoyant free-moving plastic biofilm carriers. These systems can be used for municipal and industrial wastewater treatment, aquaculture, potable water denitrification, and, in roughing, secondary, tertiary, and sidestream applications. The system includes a submerged biofilm reactor and liquid-solids separation unit. The MBBR process benefits include the following: (1) capacity to meet treatment objectives similar to activated sludge systems with respect to carbon-oxidation and nitrogen removal, but requires a smaller tank volume than a clarifier-coupled activated sludge system; (2) biomass retention is clarifier-independent and solids loading to the liquid-solids separation unit is reduced significantly when compared with activated sludge systems; (3) the MBBR is a continuous-flow process that does not require a special operational cycle for biofilm thickness, L(F), control (e.g., biologically active filter backwashing); and (4) liquid-solids separation can be achieved with a variety of processes, including conventional and compact high-rate processes. Information related to system design is fragmented and poorly documented. This paper seeks to address this issue by summarizing state-of-the art MBBR design procedures and providing the reader with an overview of some commercially available systems and their components. PMID:21751715

  20. Moving bed biofilm reactor technology: process applications, design, and performance.

    Science.gov (United States)

    McQuarrie, James P; Boltz, Joshua P

    2011-06-01

    The moving bed biofilm reactor (MBBR) can operate as a 2- (anoxic) or 3-(aerobic) phase system with buoyant free-moving plastic biofilm carriers. These systems can be used for municipal and industrial wastewater treatment, aquaculture, potable water denitrification, and, in roughing, secondary, tertiary, and sidestream applications. The system includes a submerged biofilm reactor and liquid-solids separation unit. The MBBR process benefits include the following: (1) capacity to meet treatment objectives similar to activated sludge systems with respect to carbon-oxidation and nitrogen removal, but requires a smaller tank volume than a clarifier-coupled activated sludge system; (2) biomass retention is clarifier-independent and solids loading to the liquid-solids separation unit is reduced significantly when compared with activated sludge systems; (3) the MBBR is a continuous-flow process that does not require a special operational cycle for biofilm thickness, L(F), control (e.g., biologically active filter backwashing); and (4) liquid-solids separation can be achieved with a variety of processes, including conventional and compact high-rate processes. Information related to system design is fragmented and poorly documented. This paper seeks to address this issue by summarizing state-of-the art MBBR design procedures and providing the reader with an overview of some commercially available systems and their components.

  1. Coal-bed methane in Alberta : ownership and incidental production

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, A.

    2006-04-05

    Some of the challenges facing the emerging coal-bed methane (CBM) industry in Alberta include concerns regarding water protection, compression noise, well spacing and fracturing issues. One of the most fundamental questions regarding CBM is who in fact owns the resource and what rules oversee its production. The characteristics, development potential and origins of split title ownership of CBM in North America were examined in this paper. The history of freehold and Crown-owned land and the law regarding ownership and incidental production of petroleum, natural gas and bitumen in split-title situations were reviewed. The legal status of CBM in other jurisdictions was also examined. The issues of ownership and incidental production in Alberta were also discussed. The basic common law ownership principles regarding mineral ownership were applied to the characteristics of CBM in situ to conclude its possible owner in Alberta. The extension of established incidental mineral production principles to CBM were examined in the context of its characteristics. The official governmental position on CBM issues and the prospect of future legislative intervention were identified and the implications for industry and resource companies were also presented. The paper presented several recommendations including that Alberta should legislate to eliminate any right of recovery for historical or current venting of CBM during coal mining in order to remove a cloud of uncertainty over the industry. refs.

  2. Numerical simulation of dune-flat bed transition and stage-discharge relationship with hysteresis effect

    Science.gov (United States)

    Shimizu, Y.; Giri, S.; Yamaguchi, S.; Nelson, Jack L.

    2009-01-01

    This work presents recent advances on morphodynamic modeling of bed forms under unsteady discharge. This paper includes further development of a morphodynamic model proposed earlier by Giri and Shimizu (2006a). This model reproduces the temporal development of river dunes and accurately replicates the physical properties associated with bed form evolution. Model results appear to provide accurate predictions of bed form geometry and form drag over bed forms for arbitrary steady flows. However, accurate predictions of temporal changes of form drag are key to the prediction of stage-discharge relation during flood events. Herein, the model capability is extended to replicate the dune-flat bed transition, and in turn, the variation of form drag produced by the temporal growth or decay of bed forms under unsteady flow conditions. Some numerical experiments are performed to analyze hysteresis of the stage-discharge relationship caused by the transition between dune and flat bed regimes during rising and falling stages of varying flows. The numerical model successfully simulates dune-flat bed transition and the associated hysteresis of the stage-discharge relationship; this is in good agreement with physical observations but has been treated in the past only using empirical methods. A hypothetical relationship for a sediment parameter (the mean step length) is proposed to a first level of approximation that enables reproduction of the dune-flat bed transition. The proposed numerical model demonstrates its ability to address an important practical problem associated with bed form evolution and flow resistance in varying flows. Copyright 2009 by the American Geophysical Union.

  3. Roughness coefficient and its uncertainty in gravel-bed river

    Institute of Scientific and Technical Information of China (English)

    Ji-Sung KIM; Chan-Joo LEE; Won KIM; Yong-Jeon KIM

    2010-01-01

    Manning's roughness coefficient was estimated for a gravel-bed river reach using field measurements of water level and discharge,and the applicability of various methods used for estimation of the roughness coefficient was evaluated.Results show that the roughness coefficient tends to decrease with increasing discharge and water depth,and over a certain range it appears to remain constant.Comparison of roughness coefficients calculated by field measurement data with those estimated by other methods shows that,although the field-measured values provide approximate roughness coefficients for relatively large discharge,there seems to be rather high uncertainty due to the difference in resultant values.For this reason,uncertainty related to the roughness coefficient was analyzed in terms of change in computed variables.On average,a 20%increase of the roughness coefficient causes a 7% increase in the water depth and an 8% decrease in velocity,but there may be about a 15% increase in the water depth and an equivalent decrease in velocity for certain cross-sections in the study reach.Finally,the validity of estimated roughness coefficient based on field measurements was examined.A 10% error in discharge measurement may lead to more than 10% uncertainty in roughness coefficient estimation,but corresponding uncertainty in computed water depth and velocity is reduced to approximately 5%.Conversely,the necessity for roughness coefficient estimation by field measurement is confirmed.

  4. Bubbles trapped in a fluidized bed: Trajectories and contact area

    Science.gov (United States)

    Poryles, Raphaël; Vidal, Valérie; Varas, Germán

    2016-03-01

    This work investigates the dynamics of bubbles in a confined, immersed granular layer submitted to an ascending gas flow. In the stationary regime, a central fluidized zone of parabolic shape is observed, and the bubbles follow different dynamics: either the bubbles are initially formed outside the fluidized zone and do not exhibit any significant motion over the experimental time or they are located inside the fluidized bed, where they are entrained downwards and are, finally, captured by the central air channel. The dependence of the air volume trapped inside the fluidized zone, the bubble size, and the three-phase contact area on the gas injection flow rate and grain diameter are quantified. We find that the volume fraction of air trapped inside the fluidized region is roughly constant and of the order of 2%-3% when the gas flow rate and the grain size are varied. Contrary to intuition, the gas-liquid-solid contact area, normalized by the air injected into the system, decreases when the flow rate is increased, which may have significant importance in industrial applications.

  5. Sustainability and the Fixed Bed Nuclear Reactor (FBNR

    Directory of Open Access Journals (Sweden)

    Farhang Sefidvash

    2012-08-01

    Full Text Available Sustainability as a multifaceted and holistic concept is analyzed. Sustainability involves human relationship with elements such as natural environment, economy, power, governance, education and technology with the ultimate purpose of carrying forward an ever-advancing civilization. The Fixed Bed Nuclear Reactor (FBNR is an innovative, small, simple in design, inherently safe, non-proliferating, and environmentally friendly concept that its deployment can generate energy in a sustainable manner contributing to the prosperity of humanity. The development of FBNR will provide electricity as well as desalinated water through a simple but advanced technology for the developing, as well as developed countries. FBNR is environmentally friendly due to its inherent safety and the convenience of using its spent fuel as the source of radiation for irradiation purposes in agriculture, industry, and medicine. Politically, if a ping pong game brought peace between China and USA, a program of development of FBNR supported by the peace loving international community can become a more mature means to bring peace among certain apparently hostile nations who crave sustainable energy, desalinated water and simple advanced technology.

  6. Packed bed reactor treatment of liquid hazardous and mixed wastes

    International Nuclear Information System (INIS)

    We are developing thermal-based packed bed reactor (PBR) technology as an alternative to incineration for treatment of hazardous organic liquid wastes. The waste streams targeted by this technology are machining fluids contaminated with chlorocarbons and/or chlorofluorocarbons and low levels of plutonium or tritium The PBR offers several distinct advantages including simplistic design, rugged construction, ambient pressure processing, economical operations, as well as ease of scalability and maintainability. In this paper, we provide a description of the apparatus as well as test results using prepared mixtures of machining oils/emulsions with trichloroethylene (TCE), carbon tetrachloride (CCl4), trichloroethane (TCA), and Freon TF. The current treatment system is configured as a two stage device with the PBR (1st stage) coupled to a silent discharge plasma (SDP) cell. The SDP serves as a second stage for further treatment of the gaseous effluent from the PBR. One of the primary advantages of this two stage system is that its suitability for closed loop operation where radioactive components are well contained and even CO2 is not released to the environment

  7. Experimental and Numerical Investigation of Enhancement of Heat and Mass Transfer in Adsorbent Beds

    Institute of Scientific and Technical Information of China (English)

    LiuZhenyan; FuZhumantffu

    1994-01-01

    Some interrelated parameters of heat and mass transfer in two phases of pressure rise and constant pressure are obtained by studying the desorption processes of two kinds of cylindrical adsorbent beds.with fins and without fins.Moreover,the effects of equivalent thermal conductivity of adsorbent beds,contact thermal transfer coefficient,heat transfer of fins,condensation temperature,uncondensable gas in the adsorber are analyzed.finally,enhancement of heat and mass transfer has been attained.

  8. Coal resources of selected coal beds and zones in the northern and central Appalachian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Leslie Ruppert; Susan Tewalt; Linda Bragg

    2002-02-01

    The U.S. Geological Survey (USGS) is completing a National Coal Resource Assessment of five coal-producing regions of the United States, including the Appalachian Basin. The USGS, in cooperation with the State geological surveys of Kentucky, Maryland, Ohio, Pennsylvania, Virginia, and West Virginia, has completed a digital coal resource assessment of five of the top-producing coal beds and coal zones in the northern and central Appalachian Basin coal regions -- the Pittsburgh coal bed, the Upper Freeport coal bed, the Fire Clay and Pond Creek coal zones, and the Pocahontas No. 3 coal bed. Of the 93 billion short tons of original coal in these units, about 66 billion short tons remain. 2 refs., 5 figs., 2 tabs.

  9. Mechanics Principle and Engineering Application of Split Layer and Bed Separation of Mining Overburden

    Institute of Scientific and Technical Information of China (English)

    YU Guang-ming; ZHANG Chun-hui; SU Zhong-jie; FAN Xue-li; PAN Yong-zhan; LIU Fu-shun

    2005-01-01

    To control land surface subsidence caused the underground mineral exploitation and the catastrophic phenomena such as serious damage of buildings, waterbodies, cultivated lands, railways, bridges caused by land subsidence, bed separation grouting technology of overburden is put forward. To provide theoretical support for the technology, the characteristics and the mechanics mechanism of mining overburden from layer-split to formation of bed separation are studied. On the basis of elastic sheet board theory, calculation formula of rock sheet deflection is presented, and the mechanics criteria of the separation formation and the calculation formula of bed separation volume are set up. Finally, the applications and technics of bed separation grout technology of mining overburden to control land subsidence in china are introduced.

  10. Investigation of Adsorbed Gases Content in Coal Beds in Bosnia and Herzegovina

    Directory of Open Access Journals (Sweden)

    Sadadinovic, J.

    2008-09-01

    Full Text Available Investigation of the gas fraction in coal beds in Bosnia & Herzegovina has been performed systematically since 1988. Gas in coal beds can be present in free or adsorbed form, and dissolved in water. Methods of investigation are based on the direct approach, according to which the gas fraction is determined in the undisturbed coal bed.The quantity of the adsorbed and free gas in the coal bed is directly proportional to the gas pressure. Dependence is hyperbolic. The quantity of the free gas in mining conditions is being determined by measurement of the desorption index (Δp2. The desorption index for the Srednjobosanski coal basin ranges to 1571 Pa, and the free gas pressure in this coal basin amounts up to 3.75 MPa. The desorption index for coal beds in “Kreka” and “Banoviće” coal basins has negative values, which means that the free gas fraction within the coal beds is negligible, while separation of adsorbed gases is diffuse. The free gas pressure in the mentioned coal basins is below 0.1 MPa. Adsorbed gases within the coal are connected by physical adsorption according to Langmuir’s isothermal adsorption curve. Langmuir’s quantities, for coal bed conditions, ranges as follows: am from 0.826 to 9.52 m3 t–1 pcs, and b from 6.65 10–3 to 0.247 MPa–1. Adsorbed gas within Miocene coal beds contains methane in amounts of 1.49 m3 t–1 čus CH4 andcarbon(IVoxide in amounts of 0.15 m3 t–1 čus CO2. Adsorbed gas within Pliocene coal beds, without methane, dominant is content of carbon(IVoxide.The investigation of the gas content in coal beds of BiH conducted in this article reveal that the coal beds primarily contain methane, while others hydrocarbons such as ethane, ethene, propane, propene and butane are present sporadically in fraction below φ/10–6. Based on the investigation results conducted in this article, simple mathematical forms were obtained for quick calculation of the free gas quantity by measurement of the

  11. Raising distillate selectivity and catalyst life time in Fischer-Tropsch synthesis by using a novel dual-bed reactor

    International Nuclear Information System (INIS)

    In a novel dual bed reactor Fischer-Tropsch synthesis was studied by using two diff rent cobalt catalysts. An alkali-promoted cobalt catalyst was used in the first bed of a fixed-bed reactor followed by a Raiment promoted cobalt catalyst in the second bed. The activity, product selectivity and accelerated deactivation of the system were assessed and compared with a conventional single bed reactor system. The methane selectivity in the dual-bed reactor was about 18.9% less compared to that of the single-bed reactor. The C5+ selectivity for the dual-bed reactor was 10.9% higher than that of the single-bed reactor. Accelerated deactivation of the catalysts in the dual-bed reactor was 42% lower than that of the single-bed reactor. It was revealed that the amount of catalysts activity recovery after regeneration at 400degC in the dual-bed system is higher than that of the single-bed system

  12. Storm Bed Imprinting on the Northern California Shelf: Interaction of Fluvial and Marine Processes.

    Science.gov (United States)

    Swift, D. J.; Fan, S.; Niedoroda, A. W.; Reed, C.; Borgeld, J. C.; Crockett, J. S.

    2001-05-01

    Seismic records and cores from ONR's STRATAFORM program indicate that the Holocene deposits on the northern California shelf consist of a succession of back-stepping, storm-generated event beds, deposited as sediment undergoes cross-shelf dispersal from intermittently flooding river mouths. The beds are modified to varying degrees by secondary processes (gravity transport, bioturbation). Box core observations show that there is "mud line" on the shelf surface at approximately the 45 m isobath. Long cores show that within the 3-dimensional sediment body, nearshore sand beds intertongue with offshore mud beds beneath this line. However, numerical simulations suggest a more complex relationship. Instead of intertonguing, most event beds begin as sand beds in the nearshore sand deposit, pass through an interbedded zone, and enter the offshore mud deposit as mud beds. Event stratification is difficult to discern both seaward and landward of the transitional zone, mainly because the Cutoff Percentage has been exceeded in these areas (percent thickness of an upward-fining bed which must be preserved to observe grain size contrast). There are thus three facies bodies present, an Amalgamated Sand Facies on the inner shelf (sand beds on sand beds), an Interbedded Sand and Mud Facies on the central shelf, and an offshore Laminated or Bioturbated Mud Facies. Several other parameters are useful for defining these facies. The degree of condensation (extent to which each bed has cannibalized its predecessor) can be measured by the Reworking Ratio (ratio of mean annual resuspension depth to deposition per event). This value decreases seaward across the shelf to a minimum in the Interbedded Facies in response to decreasing wave energy flux into the sea floor. It then increases seaward across the outer shelf, as the decrease in available sediment becomes more important. The standard deviation of bed thickness is (in part) a measure of variation in storm intensity, and is a

  13. Airflow attenuation and bed net utilization: observations from Africa and Asia

    DEFF Research Database (Denmark)

    von Seidlein, Lorenz; Ikonomidis, Konstantin; Bruun, Rasmus;

    2012-01-01

    for one night from 21.00 to 6.00 hrs inside and outside of bed nets using sensors and omni-directional thermo-anemometers. An investigator set up a bed net with a mesh size of 220 holes per inch2 in each study household and slept under the bed net to simulate a realistic environment. The attenuation...... of airflow caused by bed nets of different mesh sizes was also measured in an experimental wind tunnel. Results The highest indoor temperatures (49.0 C) were measured in The Gambia. During the hottest months of the year the mean temperature at night (9 pm) was between 33.1 C (The Gambia) and 26.2 C (Thailand...

  14. Geochemical "fingerprints" for Olduvai Gorge Bed II tuffs and implications for the Oldowan-Acheulean transition

    Science.gov (United States)

    McHenry, Lindsay J.; Njau, Jackson K.; de la Torre, Ignacio; Pante, Michael C.

    2016-01-01

    Bed II is a critical part of early Pleistocene Olduvai Gorge, Tanzania. Its deposits include transitions from humid to more arid conditions (with associated faunal changes), from Homo habilis to erectus, and from Oldowan to Acheulean technology. Bed II (~ 1.8-1.2 Ma) is stratigraphically and environmentally complex, with facies changes, faulting, and unconformities, making site-to-site correlation over the ~ 20 km of exposure difficult. Bed II tuffs are thinner, less evenly preserved, and more reworked than those of Bed I. Five marker tuffs (Tuffs IIA-IID, Bird Print Tuff (BPT)), plus local tephra, were collected from multiple sites and characterized using stratigraphic position, mineral assemblage, and electron probe microanalysis of phenocryst (feldspar, hornblende, augite, titanomagnetite) and glass (where available) composition. Lowermost Bed II tuffs are dominantly nephelinitic, Middle Bed II tuffs (BPT, Tuff IIC) have basaltic components, and upper Bed II Tuff IID is trachytic. The BPT and Tuff IID are identified widely using phenocryst compositions (high-Ca plagioclase and high-Ti hornblende, respectively), though IID was originally (Hay, 1976) misidentified as Tuff IIC at Loc 91 (SHK Annexe) in the Side Gorge. This work helps establish a high-resolution basin-wide paleolandscape context for the Oldowan-Acheulean transition and helps link hominin, faunal and archaeological records.

  15. Airflow attenuation and bed net utilization: observations from Africa and Asia

    Directory of Open Access Journals (Sweden)

    von Seidlein Lorenz

    2012-06-01

    Full Text Available Abstract Background/Methods Qualitative studies suggest that bed nets affect the thermal comfort of users. To understand and reduce this discomfort the effect of bed nets on temperature, humidity, and airflow was measured in rural homes in Asia and Africa, as well as in an experimental wind tunnel. Two investigators with architectural training selected 60 houses in The Gambia, Tanzania, Philippines, and Thailand. Data-loggers were used to measure indoor temperatures in hourly intervals over a 12 months period. In a subgroup of 20 houses airflow, temperature and humidity were measured at five-minute intervals for one night from 21.00 to 6.00 hrs inside and outside of bed nets using sensors and omni-directional thermo-anemometers. An investigator set up a bed net with a mesh size of 220 holes per inch2 in each study household and slept under the bed net to simulate a realistic environment. The attenuation of airflow caused by bed nets of different mesh sizes was also measured in an experimental wind tunnel. Results The highest indoor temperatures (49.0 C were measured in The Gambia. During the hottest months of the year the mean temperature at night (9 pm was between 33.1 C (The Gambia and 26.2 C (Thailand. The bed net attenuated the airflow from a minimum of 27% (Philippines to a maximum of 71% (The Gambia. Overall the bed nets reduced airflow compared to un-attenuated airflow from 9 to 4 cm sec-1 or 52% (p -2 reduced airflow by 55% (mean; range 51 - 73%. A denser net (200 holes inch-2 attenuated airflow by 59% (mean; range 56 - 74%. Discussion Despite concerted efforts to increase the uptake of this intervention in many areas uptake remains poor. Bed nets reduce airflow, but have no influence on temperature and humidity. The discomfort associated with bed nets is likely to be most intolerable during the hottest and most humid period of the year, which frequently coincides with the peak of malaria vector densities and the force

  16. Cretaceous Oceanic Red Beds: Distribution, Lithostratigraphy and Paleoenvironments

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Cretaceous oceanic red beds (CORBs) represented by red shales and marls, were deposited during the Cretaceous and early Paleocene, predominantly in the Tethyan realm, in lower slope and abyssal basin environments. Detailed studies of CORBs are rare; therefore, we compiled CORBs data from deep sea ocean drilling cores and outcrops of Cretaceous rocks subaerially exposed in southern Europe, northwestern Germany, Asia and New Zealand. In the Tethyan realm, CORBs mainly consist of reddish or pink shales, limestones and marlstones. By contrast, marlstones and chalks are rare in deep-ocean drilling cores. Upper Cretaceous marine sediments in cores from the Atlantic Ocean are predominantly various shades of brown, reddish brown, yellowish brown and pale brown in color. A few red, pink, yellow and orange Cretaceous sediments are also present. The commonest age of CORBs is early Campanian to Maastrichtian, with the onset mostly of oxic deposition often after Oceanic Anoxic Events (OAEs), during the early Aptian, late Albian-early Turonian and Campanian.This suggests an indicated and previously not recognized relationship between OAEs, black shales deposition and CORBs. CORBs even though globally distributed, are most common in the North Atlantic and Tethyan realms, in low to mid latitudes of the northern hemisphere; in the South Atlantic and Indian Ocean in the mid to high latitudes of the southern hemisphere; and are less frequent in the central Pacific Ocean. Their widespread occurrence during the late Cretaceous might have been the result of establishing a connection for deep oceanic current circulation between the Pacific and the evolving connection between South and North Atlantic and changes in oceanic basins ventilation.

  17. Bronx River bed sediments phosphorus pool and phosphorus compound identification

    Science.gov (United States)

    Wang, J.; Pant, H. K.

    2008-12-01

    Phosphorus (P) transport in the Bronx River degraded water quality, decreased oxygen levels, and resulted in bioaccumulation in sediment potentially resulting in eutrophication, algal blooms and oxygen depletion under certain temperature and pH conditions. The anthropogenic P sources are storm water runoff, raw sewage discharge, fertilizer application in lawn, golf course and New York Botanical Garden; manure from the Bronx zoo; combined sewoverflows (CSO's) from parkway and Hunts Point sewage plant; pollutants from East River. This research was conducted in the urban river system in New York City area, in order to control P source, figure out P transport temporal and spatial variations and the impact on water quality; aimed to regulate P application, sharing data with Bronx River Alliance, EPA, DEP and DEC. The sediment characteristics influence the distribution and bioavailbility of P in the Bronx River. The P sequential extraction gave the quantitative analysis of the P pool, quantifying the inorganic and organic P from the sediments. There were different P pool patterns at the 15 sites, and the substantial amount of inorganic P pool indicated that a large amount P is bioavailable. The 31P- NMR (Nuclear Magnetic Resonance Spectroscopy) technology had been used to identify P species in the 15 sites of the Bronx River, which gave a qualitative analysis on phosphorus transport in the river. The P compounds in the Bronx River bed sediments are mostly glycerophophate (GlyP), nucleoside monophosphates (NMP), polynucleotides (PolyN), and few sites showed the small amount of glucose-6-phosphate (G6P), glycerophosphoethanoamine (GPEA), phosphoenopyruvates (PEP), and inosine monophosphate (IMP). The land use spatial and temporal variations influence local water P levels, P distributions, and P compositions.

  18. Connection Between Liquid Distribution and Gas-Liquid Mass Transfer in Monolithic Bed

    Institute of Scientific and Technical Information of China (English)

    许闽; 刘辉; 李成岳; 周媛; 季生福

    2011-01-01

    With a particular focus on the connection between liquid flow distribution and gas-liquid mass transfer in monolithic beds in the Taylor flow regime, hydrodynamic and gas-liquid mass transfer experiments were carriedout in a column with a monolithic bed of cell density of 50 cpsi with trio different distributors (nozzle and packed bed distributors). Liquid saturation in individual channels was measured by using self-made micro-conductivity probes. A mal-distribution factor was used to evaluate uniform degree of phase distribution in monoliths. Overall bed pressure drop and mass transfer coefficients were measured. For liquid flow distribution and gas-liquid masstransfer, it is found that the superficial liquid velocity is a crucial factor and the packed bed distributor is better than the nozzle distributor. A semi-theoretical analysis using single channel models shows that the packed bed distributor always yields shorter and uniformly distributed liquid slugs compared to the nozzle distributor, which in turn ensures a better mass transfer performance. A bed scale mass transfer model is proposed by employing the single channel models in individual channels and incorporating effects of non-uniform liquid distribution along the bedcross-section. The model predicts the overall gas-liquid mass transfer coefficient wig a relative error within +30%.

  19. Dense Pellicular Agarose-Glass Beads for Expanded Bed Application: Flow Hydrodynamics and Solid Phase Classifications

    Institute of Scientific and Technical Information of China (English)

    周鑫; 史清洪; 白姝; 孙彦

    2004-01-01

    Two dense pellicular agarose-glass matrices of different sizes and densities, i.e., AG-S and AG-L, have been characterized for their bed expansion behavior, flow hydrodynamics and particle classifications in an expanded bed system. A 26 mm ID column with side ports was used for sampling the liquid-solid suspension during expanded bed operations. Measurements of the collected solid phase at different column positions yielded the particle size and density distribution data. It was found that the composite matrices showed particle size as well as density classifications along the column axis, i.e., both the size and density of each matrix decreased with increasing the axial bed height. Their axial classifications were expressed by a correlation related to both the particle size and density as a function of the dimensionless axial bed height. The correlation was found to fairly describe the solid phase classifications in the expanded bed system. Moreover, it can also be applied to other two commercial solid matrices designed for expanded bed applications.

  20. Bed rest attenuates sympathetic and pressor responses to isometric exercise in antigravity leg muscles in humans.

    Science.gov (United States)

    Kamiya, Atsunori; Michikami, Daisaku; Shiozawa, Tomoki; Iwase, Satoshi; Hayano, Junichiro; Kawada, Toru; Sunagawa, Kenji; Mano, Tadaaki

    2004-05-01

    Although spaceflight and bed rest are known to cause muscular atrophy in the antigravity muscles of the legs, the changes in sympathetic and cardiovascular responses to exercises using the atrophied muscles remain unknown. We hypothesized that bed rest would augment sympathetic responses to isometric exercise using antigravity leg muscles in humans. Ten healthy male volunteers were subjected to 14-day 6 degrees head-down bed rest. Before and after bed rest, they performed isometric exercises using leg (plantar flexion) and forearm (handgrip) muscles, followed by 2-min postexercise muscle ischemia (PEMI) that continues to stimulate the muscle metaboreflex. These exercises were sustained to fatigue. We measured muscle sympathetic nerve activity (MSNA) in the contralateral resting leg by microneurography. In both pre- and post-bed-rest exercise tests, exercise intensities were set at 30 and 70% of the maximum voluntary force measured before bed rest. Bed rest attenuated the increase in MSNA in response to fatiguing plantar flexion by approximately 70% at both exercise intensities (both P antigravity leg muscles.

  1. Gas Reactor International Cooperative Program. Interim report. Safety and licensing evaluaion of German Pebble Bed Reactor concepts

    Energy Technology Data Exchange (ETDEWEB)

    1978-09-01

    The Pebble Bed Gas Cooled Reactor, as developed in the Federal Republic of Germany, was reviewed from a United States Safety and Licensing perspective. The primary concepts considered were the steam cycle electric generating pebble bed (HTR-K) and the process heat pebble bed (PNP), although generic consideration of the direct cycle gas turbine pebble bed (HHT) was included. The study examines potential U.S. licensing issues and offers some suggestions as to required development areas.

  2. The Influence of Roughness and Pyrethroid Formulations on Bed Bug (Cimex lectularius L. Resting Preferences

    Directory of Open Access Journals (Sweden)

    Benjamin A. Hottel

    2015-05-01

    Full Text Available Two-choice tests were conducted to examine the effect of surface roughness on the resting preference of bed bugs, Cimex lectularius L., on copper, basswood, and acrylic materials. The influence of pyrethroid formulation applications on resting preferences was also evaluated. Bed bugs were given the choice of resting between two sanded halves of each material tested. One half was sanded with a P60 grit sandpaper and the other with a less rough P600 grit sandpaper. A significantly higher proportion of bed bugs chose to rest on the rougher P60 grit sanded half of all materials tested. Pyrethroid applications were made to either the P60 grit half or both halves of acrylic arenas and resting preferences were again assessed. Behavioral responses of bed bugs to pyrethroid formulation applications varied depending on the bed bug strain used and the formulation applied. Bed bugs would still rest on the P60 grit half when Suspend SC formulation (0.06% deltamethrin was applied; however, an avoidance response was observed from a bed bug strain susceptible to D-Force aerosol formulations (0.06% deltamethrin. The avoidance behavior is likely attributed to one, more than one, or even an interaction of multiple spray constituents and not the active ingredient.

  3. The Influence of Roughness and Pyrethroid Formulations on Bed Bug (Cimex lectularius L.) Resting Preferences.

    Science.gov (United States)

    Hottel, Benjamin A; Pereira, Roberto M; Koehler, Philip G

    2015-01-01

    Two-choice tests were conducted to examine the effect of surface roughness on the resting preference of bed bugs, Cimex lectularius L., on copper, basswood, and acrylic materials. The influence of pyrethroid formulation applications on resting preferences was also evaluated. Bed bugs were given the choice of resting between two sanded halves of each material tested. One half was sanded with a P60 grit sandpaper and the other with a less rough P600 grit sandpaper. A significantly higher proportion of bed bugs chose to rest on the rougher P60 grit sanded half of all materials tested. Pyrethroid applications were made to either the P60 grit half or both halves of acrylic arenas and resting preferences were again assessed. Behavioral responses of bed bugs to pyrethroid formulation applications varied depending on the bed bug strain used and the formulation applied. Bed bugs would still rest on the P60 grit half when Suspend SC formulation (0.06% deltamethrin) was applied; however, an avoidance response was observed from a bed bug strain susceptible to D-Force aerosol formulations (0.06% deltamethrin). The avoidance behavior is likely attributed to one, more than one, or even an interaction of multiple spray constituents and not the active ingredient. PMID:26463196

  4. Diffusion Rates and Dispersal Patterns of Unfed versus Recently Fed Bed Bugs (Cimex lectularius L.

    Directory of Open Access Journals (Sweden)

    Jerome Goddard

    2015-09-01

    Full Text Available Bed bug problems have been increasing since the 1980s, and accordingly, there have been intensive efforts to better understand their biology and behavior for control purposes. Understanding bed bug diffusion rates and dispersal patterns from one site to another (or lack thereof is a key component in prevention and control campaigns. This study analyzed diffusion rates and dispersal patterns in a population of bed bugs, recently fed and unfed, in both one-dimensional and two-dimensional settings. When placed in the middle of a 71 cm × 2.7 cm artificial lane, approximately half of the bugs regardless of feeding status stayed at or near the release point during the 10 min observation periods, while about a fourth of them walked to the end of the lane. When placed in the middle of an arena measuring 51 cm × 76 cm and allowed to walk in any direction, approximately one-fourth of bed bugs, fed or unfed, still remained near their release point (no significant difference between fed or unfed. As for long-distance dispersal, 11/50 (22% of recently fed bed bugs moved as far as possible in the arena during the 10 min replications, while only 2/50 (4% unfed bed bugs moved to the maximum distance. This difference was significantly different (p < 0.0038, and indicates that unfed bed bugs did not move as far as recently fed ones. A mathematical diffusion model was used to quantify bed bug movements and an estimated diffusion rate range of 0.00006 cm2/s to 0.416 cm2/s was determined, which is almost no movement to a predicted root mean squared distance of approximately 19 cm per 10 min. The results of this study suggest that bed bugs, upon initial introduction into a new area, would have a difficult time traversing long distances when left alone to randomly disperse.

  5. FLUIDIZED BED STEAM REFORMER (FBSR) PRODUCT: MONOLITH FORMATION AND CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C

    2006-09-13

    The most important requirement for Hanford's low activity waste (LAW) form for shallow land disposal is the chemical durability of the product. A secondary, but still essential specification, is the compressive strength of the material with regards to the strength of the material under shallow land disposal conditions, e.g. the weight of soil overburden and potential intrusion by future generations, because the term ''near-surface disposal'' indicates disposal in the uppermost portion, or approximately the top 30 meters, of the earth's surface. The THOR{reg_sign} Treatment Technologies (TTT) mineral waste form for LAW is granular in nature because it is formed by Fluidized Bed Steam Reforming (FBSR). As a granular product it has been shown to be as durable as Hanford's LAW glass during testing with ASTM C-1285-02 known as the Product Consistency Test (PCT) and with the Single Pass Flow Through Test (SPFT). Hanford Envelope A and Envelope C simulants both performed well during PCT and SPFT testing and during subsequent performance assessment modeling. This is partially due to the high aluminosilicate content of the mineral product which provides a natural aluminosilicate buffering mechanism that inhibits leaching and is known to occur in naturally occurring aluminosilicate mineral analogs. In order for the TTT Na-Al-Si (NAS) granular mineral product to meet the compressive strength requirements (ASTM C39) for a Hanford waste form, the granular product needs to be made into a monolith or disposed of in High Integrity Containers (HIC's). Additionally, the Hanford intruder scenario for disposal in the Immobilized Low Activity Waste (ILAW) trench is mitigated as there is reduced intruder exposure when a waste form is in a monolithic form. During the preliminary testing of a monolith binder for TTT's FBSR mineral product, four parameters were monitored: (1) waste loading (not optimized for each waste form tested); (2) density

  6. Behavior of Alkali Metals and Ash in a Low-Temperature Circulating Fluidized Bed (LTCFB) Gasifier

    DEFF Research Database (Denmark)

    Narayan, Vikas; Jensen, Peter Arendt; Henriksen, Ulrik Birk;

    2016-01-01

    , the low reactor temperature ensures that high-alkali biomass fuels canbe used without risk of bed defluidization. This paper presents the first investigation of the fate of alkali metals and ash in lowtemperaturegasifiers. Measurements on bed material and product gas dust samples were made on a 100 k......A low-temperature circulating fluidized bed system (LTCFB) gasifier allows for pyrolysis and gasification to occurat low temperatures, thereby improving the retention of alkali and other inorganic elements within the system and minimizingthe amount of ash species in the product gas. In addition...

  7. Experimental studies on heat transfer and pressure drop in pebble bed test facility

    International Nuclear Information System (INIS)

    Indian program for development of high temperature reactor and its utilization to supply process heat aimed to develop alternate fuel carrier to substitute petroleum based transport fuel, which has very small reserves in India and results in large import bills. Hydrogen is an attractive energy carrier for transport applications. It can be produced by splitting water which requires either electricity or process heat at high temperatures or both depending upon the process selected. BARC is carrying out design of a 600 MWth reactor capable of supplying process heat at around 1000 °C as required for hydrogen production. For this reactor various design options with respect to fuel configurations, such as prismatic bed and pebble bed were considered for thermal hydraulics analysis. Coolant options such as molten lead and molten salt were analyzed. Studies carried out indicate selection of pebble bed reactor core with molten salt as coolant. Thermal-hydraulic studies are required for pebble bed reactor. With this in view, a pebble bed test facility has been setup to study the heat transfer and pressure drop in pebble bed. Water is used as a working medium for the facility. The paper deals with the description of the pebble bed test facility and the experimental results of heat transfer and pressure drop. It also deals with the assessment of correlations for heat transfer and pressure drop in pebble bed geometry. Pressure drop experiments in the pebble bed test facility have been performed for Raynolds number ranges from 3000-12000. Various pressure drop correlations have been compared with the experimental data. It has been found that that the correlation given by Leva et. al. matches well with the experimental data. Various heat transfer correlations have also been compared. Heat transfer experiments are nearing completion

  8. Mathematical Simulation of the Structural Properties of Packed and Fluidized Beds

    Science.gov (United States)

    Fedorov, S. S.; Gubinskii, M. V.; Foris', S. N.

    2016-05-01

    Based on the algorithm of successive filling a given volume with single spheres, a mathematical model of random packing of a limited volume of a bed in the field of body forces has been developed. This model can be applied to electrothermal packed- and fluidized-bed furnaces and will make it possible to investigate the thermal and electrical conductivity of such beds. A check of the adequacy of the model showed its correspondence to the well-known experimental and calculated results, as well as the stability of the solutions obtained with its aid.

  9. An overview of separation by magnetically stabilized beds: State-of-the-art and potential applications

    Institute of Scientific and Technical Information of China (English)

    Jordan; Hristov; Ludmil; Fachikov

    2007-01-01

    This article deals with problems relevant to implementation of magnetically stabilized beds (MSB) as separation devices. The main issues discussed are: bed mechanics, bed structure, possibilities to create controllable filter media, etc. As examples several separation techniques are discussed: dust filtration-magnetic and non-magnetic, ion-exchange, copper cementation, yeast filtration from biological liquids, particle separation by density and magnetic properties, dangerous wastes removal. Only key publications will be quoted that provide a basis for further reading and study and relevant information.

  10. The Effects of Long Duration Bed Rest on Brain Functional Connectivity and Sensorimotor Functioning

    Science.gov (United States)

    Cassady, K.; Koppelmans, V.; De Dios, Y.; Stepanyan, V.; Szecsy, D.; Gadd, N.; Wood, S.; Reuter-Lorenz, P.; Castenada, R. Riascos; Kofman, I.; Bloomberg, J.; Mulavara, A; Seidler, R.

    2016-01-01

    Long duration spaceflight has been associated with detrimental alterations in human sensorimotor functioning. Prolonged exposure to a head-down tilt (HDT) position during long duration bed rest can resemble several effects of the microgravity environment such as reduced sensory inputs, body unloading and increased cephalic fluid distribution. The question of whether microgravity affects other central nervous system functions such as brain functional connectivity and its relationship with behavior is largely unknown, but of importance to the health and performance of astronauts both during and post-flight. In the present study, we investigate the effects of prolonged exposure to HDT bed rest on resting state brain functional connectivity and its association with behavioral changes in 17 male participants. To validate that our findings were not due to confounding factors such as time or task practice, we also acquired resting state functional magnetic resonance imaging (rs-fMRI) and behavioral measurements from 14 normative control participants at four time points. Bed rest participants remained in bed with their heads tilted down six degrees below their feet for 70 consecutive days. Rs-fMRI and behavioral data were obtained at seven time points averaging around: 12 and 8 days prior to bed rest; 7, 50, and 70 days during bed rest; and 8 and 12 days after bed rest. 70 days of HDT bed rest resulted in significant increases in functional connectivity during bed rest followed by a reversal of changes in the post bed rest recovery period between motor cortical and somatosensory areas of the brain. In contrast, decreases in connectivity were observed between temporoparietal regions. Furthermore, post-hoc correlation analyses revealed a significant relationship between motor-somatosensory network connectivity and standing balance performance changes; participants that exhibited the greatest increases in connectivity strength showed the least deterioration in postural

  11. Mercury cycling in stream ecosystems. 2. Benthic methylmercury production and bed sediment - Pore water partitioning

    Science.gov (United States)

    Marvin-DiPasquale, M.; Lutz, M.A.; Brigham, M.E.; Krabbenhoft, D.P.; Aiken, G.R.; Orem, W.H.; Hall, B.D.

    2009-01-01

    Mercury speciation, controls on methylmercury (MeHg) production, and bed sediment - pore water partitioning of total Hg (THg) and MeHg were examined in bed sediment from eight geochemically diverse streams where atmospheric deposition was the predominant Hg input. Across all streams, sediment THg concentrations were best described as a combined function of sediment percent fines (%fines; particles water distribution coefficients (log Kd's) for both THg and MeHg were inversely related to the log-transformed ratio of pore water dissolved organic carbon (DOC) to bed sediment %fines. The stream with the highest drainage basin wetland density also had the highest pore water DOC ?? 2009 American Chemical Society.

  12. Fluidization and coating of very dense powders by fluidized bed chemical vapour deposition

    OpenAIRE

    Rodriguez, Philippe; Caussat, Brigitte; Ablitzer, Carine; Iltis, Xavière; Brothier, Méryl

    2013-01-01

    The hydrodynamic behaviour of a very dense tungsten powder, 75 µm in median diameter and 19,300 kg/m3 in grain density, has been studied in a fluidized bed at room temperature using nitrogen and argon as carrier gas. Even if fluidization was achieved, the small bed expansion indicated that it was imperfect. Then, the fluidization was studied at 400 °C in order to investigate the feasibility of coating this powder by Fluidized Bed Chemical Vapour Deposition (FBCVD). In particular, the influenc...

  13. Bioreactors with Light-Beads Fluidized Bed: The Voidage Function and its Expression

    Directory of Open Access Journals (Sweden)

    Iliev Vasil

    2014-12-01

    Full Text Available Light-beads fluidized bed bioreactors with gel particles are an attractive alternative for the implementation of a system with immobilized cells. They have a number of advantages: soft operating conditions, ability to work in an ideal mixing regime, intensification of heat- and mass transfer processes in the fermentation system. The expansion characteristics of the fluidized bed were investigated in the present work. The fluidized bed expansion was described using the voidage function. It was found that the voidage can be described by nonlinear regression relationships and the regression coefficients were a function of the particles parameters.

  14. COMPARISON OF MONODISPERSE AND POLYDISPERSE AEROSOL DEPOSITION IN A PACKED BED

    Science.gov (United States)

    COMPARISON OF MONODISPERSE AND POLYDISPERSE AEROSOL DEPOSITION IN A PACKED BED. Jacky A. Rosati, Dept. of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC 27599; Chong S. Kim, USEPA National Health and Environmental Effects Research Laboratory...

  15. Sensitivity of growth characteristics of tidal sand ridges and long bed waves to formulations of bed shear stress, sand transport and tidal forcing: A numerical model study

    Science.gov (United States)

    Yuan, Bing; de Swart, Huib E.; Panadès, Carles

    2016-09-01

    Tidal sand ridges and long bed waves are large-scale bedforms that are observed on continental shelves. They differ in their wavelength and in their orientation with respect to the principal direction of tidal currents. Previous studies indicate that tidal sand ridges appear in areas where tidal currents are above 0.5 m s-1, while long bed waves occur in regions where the maximum tidal current velocity is slightly above the critical velocity for sand erosion and the current is elliptical. An idealized nonlinear numerical model was developed to improve the understanding of the initial formation of these bedforms. The model governs the feedbacks between tidally forced depth-averaged currents and the sandy bed on the outer shelf. The effects of different formulations of bed shear stress and sand transport, tidal ellipticity and different tidal constituents on the characteristics of these bedforms (growth rate, wavelength, orientation of the preferred bedforms) during their initial formation were examined systematically. The results show that the formulations for bed shear stress and slope-induced sand transport are not critical for the initial formation of these bedforms. For tidal sand ridges, under rectilinear tidal currents, increasing the critical bed shear stress for sand erosion decreases the growth rate and the wavelength of the preferred bedforms significantly, while the orientation angle slightly decreases. The dependence of the growth rate, wavelength and the orientation of the preferred bedforms on the tidal ellipticity is non-monotonic. A decrease in tidal frequency results in preferred bedforms with larger wavelength and smaller orientation angle, while their growth rate hardly changes. In the case of joint diurnal and semidiurnal tides, or spring-neap tides, the characteristics of the bedforms are determined by the dominant tidal constituent. For long bed waves, the number of anticyclonically/cyclonically oriented bedforms with respect to the principal

  16. Real time test bed development for power system operation, control and cyber security

    Science.gov (United States)

    Reddi, Ram Mohan

    The operation and control of the power system in an efficient way is important in order to keep the system secure, reliable and economical. With advancements in smart grid, several new algorithms have been developed for improved operation and control. These algorithms need to be extensively tested and validated in real time before applying to the real electric power grid. This work focuses on the development of a real time test bed for testing and validating power system control algorithms, hardware devices and cyber security vulnerability. The test bed developed utilizes several hardware components including relays, phasor measurement units, phasor data concentrator, programmable logic controllers and several software tools. Current work also integrates historian for power system monitoring and data archiving. Finally, two different power system test cases are simulated to demonstrate the applications of developed test bed. The developed test bed can also be used for power system education.

  17. Heat Transfer in Segregated Fluidized Beds Part 2: Particle Motion and Its Effects on the Heat transfer in the Segregated Fluidized Beds

    Science.gov (United States)

    Gu, Yihua; Satoh, Isao; Saito, Takushi; Kawaguchi, Tatsuya

    In our previous paper, particle and temperature segregations in a fluidized bed of binary particle mixtures were experimentally examined, and heat transfer in the segregated fluidized bed was investigated. As the results, it was shown that the temperature segregation results mainly from low heat transfer coefficient through the interface layer, which exists between the flotsam-rich and jetsam-rich layers, and that the heat transfer coefficient increases rapidly with increasing the excess gas velocity. Following our previous paper, particle motion in the segregated fluidized bed was experimentally investigated in this paper, in order to make quantitative discussion on the relation between the heat transfer coefficient and particle motion in the interface layer. In the experiment, the Particle Imaging Velocimetry (PIV) method was applied to study the concentration and motion of particles in the segregated fluidized bed. A modified solid circulation model was built up to model the particle motion in the segregated fluidized bed. The experiment results showed that the vertical particle exchange rate of the interface layer increases with the excess gas velocity, and that the vertical heat transfer coefficient through the interface layer is mainly determined by the average particle exchange rate in the interface layer. Variations of the apparent thermal conductivity at different height in the particle layers were also determined by the vertical variation of the particle exchange rate. It was shown that the heat transfer coefficient or the thermal conductivity in the interface layer is influenced by the densities and specific heat capacities of the particles.

  18. Mark-Release-Recapture Reveals Extensive Movement of Bed Bugs (Cimex lectularius L. within and between Apartments.

    Directory of Open Access Journals (Sweden)

    Richard Cooper

    Full Text Available Understanding movement and dispersal of the common bed bug (Cimex lectularius L. under field conditions is important in the control of infestations and for managing the spread of bed bugs to new locations. We investigated bed bug movement within and between apartments using mark-release-recapture (m-r-r technique combined with apartment-wide monitoring using pitfall-style interceptors. Bed bugs were collected, marked, and released in six apartments. The distribution of marked and unmarked bed bugs in these apartments and their 24 neighboring units were monitored over 32 days. Extensive movement of marked bed bugs within and between apartments occurred regardless of the number of bed bugs released or presence/absence of a host. Comparison of marked and unmarked bed bug distributions confirms that the extensive bed bug activity observed was not an artifact of the m-r-r technique used. Marked bed bugs were recovered in apartments neighboring five of six m-r-r apartments. Their dispersal rates at 14 or 15 d were 0.0-5.0%. The estimated number of bed bugs per apartment in the six m-r-r apartments was 2,433-14,291 at 4-7 d after release. Longevity of bed bugs in the absence of a host was recorded in a vacant apartment. Marked large nymphs (3rd- 5th instar, adult females, and adult males continued to be recovered up to 57, 113, and 134 d after host absence, respectively. Among the naturally existing unmarked bed bugs, unfed small nymphs (1st- 2nd instar were recovered up to 134 d; large nymphs and adults were still found at 155 d when the study ended. Our findings provide important insight into the behavioral ecology of bed bugs in infested apartments and have significant implications in regards to eradication programs and managing the spread of bed bugs within multi-occupancy dwellings.

  19. Mark-Release-Recapture Reveals Extensive Movement of Bed Bugs (Cimex lectularius L.) within and between Apartments.

    Science.gov (United States)

    Cooper, Richard; Wang, Changlu; Singh, Narinderpal

    2015-01-01

    Understanding movement and dispersal of the common bed bug (Cimex lectularius L.) under field conditions is important in the control of infestations and for managing the spread of bed bugs to new locations. We investigated bed bug movement within and between apartments using mark-release-recapture (m-r-r) technique combined with apartment-wide monitoring using pitfall-style interceptors. Bed bugs were collected, marked, and released in six apartments. The distribution of marked and unmarked bed bugs in these apartments and their 24 neighboring units were monitored over 32 days. Extensive movement of marked bed bugs within and between apartments occurred regardless of the number of bed bugs released or presence/absence of a host. Comparison of marked and unmarked bed bug distributions confirms that the extensive bed bug activity observed was not an artifact of the m-r-r technique used. Marked bed bugs were recovered in apartments neighboring five of six m-r-r apartments. Their dispersal rates at 14 or 15 d were 0.0-5.0%. The estimated number of bed bugs per apartment in the six m-r-r apartments was 2,433-14,291 at 4-7 d after release. Longevity of bed bugs in the absence of a host was recorded in a vacant apartment. Marked large nymphs (3rd- 5th instar), adult females, and adult males continued to be recovered up to 57, 113, and 134 d after host absence, respectively. Among the naturally existing unmarked bed bugs, unfed small nymphs (1st- 2nd instar) were recovered up to 134 d; large nymphs and adults were still found at 155 d when the study ended. Our findings provide important insight into the behavioral ecology of bed bugs in infested apartments and have significant implications in regards to eradication programs and managing the spread of bed bugs within multi-occupancy dwellings. PMID:26352145

  20. Fluid and salt supplementation effect on body hydration and electrolyte homeostasis during bed rest and ambulation

    Science.gov (United States)

    Zorbas, Yan G.; Kakurin, Vassily J.; Kuznetsov, Nikolai A.; Yarullin, Vladimir L.

    2002-06-01

    Bed rest (BR) induces significant urinary and blood electrolyte changes, but little is known about the effect of fluid and salt supplements (FSS) on catabolism, hydration and electrolytes. The aim was to measure the effect of FSS on catabolism, body hydration and electrolytes during BR. Studies were done during 7 days of a pre-bed rest period and during 30 days of a rigorous bed rest period. Thirty male athletes aged, 24.6±7.6 years were chosen as subjects. They were divided into three groups: unsupplemented ambulatory control subjects (UACS), unsupplemented bed rested subjects (UBRS) and supplemented bed rested subjects (SBRS). The UBRS and SBRS groups were kept under a rigorous bed rest regime for 30 days. The SBRS daily took 30 ml water per kg body weight and 0.1 sodium chloride per kg body weight. Plasma sodium (Na), potassium (K), calcium (Ca) and magnesium (Mg) levels, urinary Na, K, Ca and Mg excretion, plasma osmolality, plasma protein level, whole blood hemoglobin (Hb) and hematocrit (Hct) level increased significantly ( p≤0.05), while plasma volume (PV), body weight, body fat, peak oxygen uptake, food and fluid intake decreased significantly ( p≤0.05) in the UBRS group when compared with the SBRS and UACS groups. In contrast, plasma and urinary electrolytes, osmolality, protein level, whole blood Hct and Hb level decreased significantly ( p≤0.05), while PV, fluid intake, body weight and peak oxygen uptake increased significantly ( p≤0.05) in the SBRS group when compared with the UBRS group. The measured parameters did not change significantly in the UACS group when compared with their baseline control values. The data indicate that FSS stabilizes electrolytes and body hydration during BR, while BR alone induces significant changes in electrolytes and body hydration. We conclude that FSS may be used to prevent catabolism and normalize body hydration status and electrolyte values during BR.

  1. Stability and scour development of bed material on crossbar block ramps

    Institute of Scientific and Technical Information of China (English)

    Mario OerteLa; DanieLB Bung

    2015-01-01

    Block ramps are ecologically oriented drop structures with adequate energy dissipation and partially moderate flow velocities. A special case is given with crossbar block ramps, where the upstream and downstream level difference is reduced by a series of basins. To prevent the total structure from failing, the stability of single boulders within the crossbars and the bed material in between must be guaranteed. The present paper addresses the stability of bed material and scour development for various flow regimes. Any bed material erosion may affect the stability of the crossbar boulders, which in turn can result in major damages of the ramp. Therefore new design approaches are developed to choose an appropriate bed material size and to avoid failures of crossbar block ramp structures.

  2. Evaluation and Clustering Maps of Groundwater Wells in the Red Beds of Chengdu, Sichuan, China

    Directory of Open Access Journals (Sweden)

    Haijing Zhang

    2016-01-01

    Full Text Available Since the start of the 21st century, groundwater wells have been placed in red beds to solve the problem of scarce water resources in Southwest China and have rapidly expanded to other areas. By providing examples of cartography in Chengdu and Sichuan, China, and using the locations of groundwater in fractures and pores when monitoring and managing red sandstone and mudstone wells, a series of maps of groundwater wells at different scales in the red beds of Chengdu was obtained. Most of the wells located in red beds are located in Jintang, Dayi, and Qingbaijiang and exhibit different cluster features. The kernel density estimation and spatial cluster analysis classification methods were used based on the Density Based Spatial Clustering of Applications with Noise algorithm (DBSCAN in three concentrated areas. This method describes the trends of the clustering results and the relationships between the locations of residents and red bed wells. The cartography results show that the groundwater wells in red beds are mainly distributed in hilly areas and partially correspond with the locations of villages and settlements, particularly their geological and topographic factors, which satisfy the maximum requirements of water use and recycling in Southwest China. The irrigation wells located in red beds are not only reliable and efficient but also replace inefficient water resources in the recharge-runoff-discharge groundwater process, which promotes the sustainable development of groundwater resources.

  3. Upper Freeport Coal Bed County Statistics (Geology) in Pennsylvania, Ohio, West Virginia, and Maryland

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon coverage of counties limited to the extent of the Upper Freeport coal bed resource areas and attributed with statistics on the thickness...

  4. Upper Freeport Coal Bed Point Data (Geology) in Pennsylvania, Ohio, West Virginia, and Maryland

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a point coverage of attributes on data location, thickness of the Upper Freeport coal bed, and its elevation, in feet. The file is also found as an...

  5. Pittsburgh Coal Bed Resource Areas in Pennsylvania, Ohio, West Virginia, and Maryland

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The base of the Pittsburgh Coal bed and its stratigraphically (non-coal) equivalent horizon is used to subdivide Upper Pennsylvanian Series strata into the...

  6. TIN Dataset Model of the Mahogany Bed Structure in the Uinta Basin, Utah and Colorado

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — An ESRI TIN data model of the Mahogany bed structure was needed to perform overburden calculations in the Uinta Basin, Utah and Colorado as part of a 2009 National...

  7. Raster Dataset Model of the Mahogany Bed Structure in the Uinta Basin, Utah and Colorado

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — An ESRI GRID raster data model of the Mahogany bed structure was needed to perform overburden calculations in the Uinta Basin, Utah and Colorado as part of a 2009...

  8. Pittsburgh Coal Bed Point Data (Geology) in Pennsylvania, Ohio, West Virginia, and Maryland

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a point coverage of attributes on data location, thickness of the Pittsburgh coal bed main bench, and its elevation, in feet. The file is also found...

  9. Raster Dataset Model of Overburden Above the Mahogany Bed in the Uinta Basin, Utah and Colorado

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — An ESRI GRID raster data model of the overburden material above the Mahogany bed was needed to perform calculations in the Uinta Basin, Utah and Colorado as part of...

  10. Upper Freeport Coal Bed County Statistics (Chemistry) in Pennsylvania, Ohio, West Virginia, and Maryland

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon coverage of counties limited to the extent of the Upper Freeport coal bed resource areas and attributed with statistics on these coal...

  11. Measurement of intergranular stress and porosity during dynamic compaction of porous beds of cyclotetramethylene tetranitramine

    Science.gov (United States)

    Greenaway, M. W.

    2005-05-01

    The dynamic compaction of granular beds of the propellant cyclotetramethylene tetranitramine (HMX) has been investigated using a modified split Hopkinson pressure bar system. Intergranular stress and bed porosity were simultaneously measured during controlled loading. The importance of grain size was investigated by comparing conventional HMX (mean particle size ˜260μm) to microfine HMX (hydraulically pressing the beds prior to testing. With large grains, resistance to compaction increased with the solid volume fraction. Microfine HMX behaved like low porosity conventional HMX beds in all cases. Porosity was typically reduced by 5%-10% during compaction and intergranular stresses below the yield stress were ensured. Energy dissipation to plastic flow and fracture were largely eliminated. Optical particle size analysis and electron microscopy support the experimental observations.

  12. Pocahontas No. 3 Coal Bed County Statistics (Geology) in Kentucky, West Virginia, and Virginia

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon coverage of counties limited to the extent of the Pocahontas No. 3 coal bed resource areas and attributed with statistics on the thickness...

  13. TIN Dataset Model of Overburden Above the Mahogany Bed in the Uinta Basin, Utah and Colorado

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — An ESRI TIN data model of the overburden material above the Mahogany bed was needed to perform calculations in the Uinta Basin, Utah and Colorado as part of a 2009...

  14. Pocahontas No. 3 Coal Bed County Statistics (Chemistry) in West Virginia and Virginia

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon coverage of counties limited to the extent of the Pocahontas No. 3 coal bed resource areas and attributed with statistics on these coal...

  15. Pittsburgh Coal Bed County Statistics (Geology) in Pennsylvania, Ohio, West Virginia, and Maryland

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon coverage of counties limited to the extent of the Pittsburgh coal bed resource areas and attributed with statistics on the thickness of...

  16. Pittsburgh Coal Bed Original Resources by County in Pennsylvania, Ohio, West Virginia, and Maryland

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon coverage of counties limited to the extent of the Pittsburgh coal bed resource areas and attributed with original resource values...

  17. Upper Freeport Coal Bed Remaining Resources by County in Pennsylvania, Ohio, West Virginia, and Maryland

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon coverage of counties limited to the extent of the Upper Freeport coal bed resource areas and attributed with remaining resources (millions...

  18. Pocahontas No. 3 Coal Bed Remaining Resources by County in Kentucky, West Virginia, and Virginia

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon coverage of counties limited to the extent of the Pocahontas No. 3 coal bed resource areas and attributed with remaining resource values...

  19. Pocahontas No. 3 Coal Bed Original Resources by County in Kentucky, West Virginia, and Virginia

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon coverage of counties limited to the extent of the Pocahontas No. 3 coal bed resource areas and attributed with original resource values...

  20. Pittsburgh Coal Bed Remaining Resources by County in Pennsylvania, Ohio, West Virginia, and Maryland

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon coverage of counties limited to the extent of the Pittsburgh coal bed resource areas and attributed with remaining resource values in...

  1. Pittsburgh Coal Bed County Statistics (Chemistry) in Pennsylvania, Ohio, West Virginia, and Maryland

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon coverage of counties limited to the extent of the Pittsburgh coal bed resource areas and attributed with statistics on these coal quality...

  2. Lower Kittanning Coal Bed County Statistics (Chemistry) in Pennsylvania, Ohio, West Virginia, and Maryland

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon coverage of counties limited to the extent of the Lower Kittanning coal bed resource areas and attributed with statistics on these coal...

  3. Vitamin D: Findings from Antarctic, Bed Rest, Houston, and ISS

    Science.gov (United States)

    Zwart, Sara R.; Locke, J.; Pierson, D.; Mehta, S.; Bourbeau, Y.; Parsons, H.; Smith, S. M.

    2009-01-01

    Obtaining vitamin D is critical for space travelers because they lack ultraviolet light exposure and have an insufficient dietary supply of vitamin D. Despite the provision of 400 IU vitamin D supplements to International Space Station (ISS) early crewmembers, vitamin D status was consistently lower after flight than before flight, and in several crewmembers has decreased to levels considered clinically significant. Vitamin D has long been known to play a role in calcium metabolism, and more recently its non-calcitropic functions have been recognized. According to the results of several recent studies, functionally relevant measures indicate that the lower limit of serum 25-hydroxyvitamin D (a marker of vitamin D status) should be raised from the current 23 nmol/L to 80 nmol/L. The mean preflight serum 25-hydroxyvitamin D (25-OH vit D) for U.S. ISS crewmembers to date is 63 +/- 16 nmol/L, and after a 4- to 6-mo space flight it typically decreases 25-30% despite supplementation (400 IU/d). The sub-optimal pre- and postflight vitamin D status is an issue that needs to be addressed, to allow NASA to better define the appropriate amount of supplemental vitamin D to serve as a countermeasure against vitamin D deficiency in astronaut crews. A series of ground-based and flight studies in multiple models have been conducted, including Antarctica in winter months when UV-B radiation levels are essentially zero, bed rest where subjects are not exposed to UV-B radiation for 60-90 days, in free-living individuals in Houston, and in International Space Station crewmembers. In these studies, we looked at dose regimen and efficacy, compliance issues, as well as toxicity. Preliminary results from these studies will be presented. Together, the data from these studies will enable us to provide space crews with evidence-based recommendations for vitamin D supplementation. The findings also have implications for other persons with limited UV light exposure, including polar workers and

  4. A biphasic oxidation of alcohols to aldehydes and ketones using a simplified packed-bed microreactor

    OpenAIRE

    Andrew Bogdan; D. Tyler McQuade

    2009-01-01

    We demonstrate the preparation and characterization of a simplified packed-bed microreactor using an immobilized TEMPO catalyst shown to oxidize primary and secondary alcohols via the biphasic Anelli-Montanari protocol. Oxidations occurred in high yields with great stability over time. We observed that plugs of aqueous oxidant and organic alcohol entered the reactor as plugs but merged into an emulsion on the packed-bed. The emulsion coalesced into larger plugs upon exiting the reactor, leavi...

  5. An Experimental and Numerical Investigation of Fluidized Bed Gasification of Solid Waste

    OpenAIRE

    Sharmina Begum; Mohammad G. Rasul; Delwar Akbar; David Cork

    2013-01-01

    Gasification is a thermo-chemical process to convert carbon-based products such as biomass and coal into a gas mixture known as synthetic gas or syngas. Various types of gasification methods exist, and fluidized bed gasification is one of them which is considered more efficient than others as fuel is fluidized in oxygen, steam or air. This paper presents an experimental and numerical investigation of fluidized bed gasification of solid waste (SW) (wood). The experimental measurement of syngas...

  6. Biometrics for Emotion Detection (BED): Exploring the combination of Speech and ECG

    OpenAIRE

    Schut, Marleen H.; Tuinenbreijer, Kees; Broek, van den, E.; Westerink, Joyce H.D.M.; Kim, Jonghwa; Karjalainen, Pasi

    2010-01-01

    The paradigm Biometrics for Emotion Detection (BED) is introduced, which enables unobtrusive emotion recognition, taking into account varying environments. It uses the electrocardiogram (ECG) and speech, as a powerful but rarely used combination to unravel people’s emotions. BED was applied in two environments (i.e., office and home-like) in which 40 people watched 6 film scenes. It is shown that both heart rate variability (derived from the ECG) and, when people’s gender is taken into accoun...

  7. Sex of college students moderates associations among bedtime, time in bed, and circadian phase angle

    OpenAIRE

    Van Reen, Eliza; Sharkey, Katherine M.; Roane, Brandy M.; Barker, David; Seifer, Ronald; Raffray, Tifenn; Bond, Tamara L.; Carskadon, Mary A.

    2013-01-01

    Sex differences in circadian rhythms have been reported with some conflicting results. The timing of sleep and length of time in bed has not been considered, however, in previous such studies. The current study has three major aims: (1) replicate previous studies in a large sample of young adults for sex differences in sleep patterns and dim light melatonin onset (DLMO) phase; (2) in a subsample constrained by matching across sex for bedtime and time in bed, confirm sex differences in DLMO an...

  8. Mounted Smartphones as Measurement and Control Platforms for Motor-Based Laboratory Test-Beds.

    Science.gov (United States)

    Frank, Jared A; Brill, Anthony; Kapila, Vikram

    2016-01-01

    Laboratory education in science and engineering often entails the use of test-beds equipped with costly peripherals for sensing, acquisition, storage, processing, and control of physical behavior. However, costly peripherals are no longer necessary to obtain precise measurements and achieve stable feedback control of test-beds. With smartphones performing diverse sensing and processing tasks, this study examines the feasibility of mounting smartphones directly to test-beds to exploit their embedded hardware and software in the measurement and control of the test-beds. This approach is a first step towards replacing laboratory-grade peripherals with more compact and affordable smartphone-based platforms, whose interactive user interfaces can engender wider participation and engagement from learners. Demonstrative cases are presented in which the sensing, computation, control, and user interaction with three motor-based test-beds are handled by a mounted smartphone. Results of experiments and simulations are used to validate the feasibility of mounted smartphones as measurement and feedback control platforms for motor-based laboratory test-beds, report the measurement precision and closed-loop performance achieved with such platforms, and address challenges in the development of platforms to maintain system stability. PMID:27556464

  9. Mounted Smartphones as Measurement and Control Platforms for Motor-Based Laboratory Test-Beds

    Science.gov (United States)

    Frank, Jared A.; Brill, Anthony; Kapila, Vikram

    2016-01-01

    Laboratory education in science and engineering often entails the use of test-beds equipped with costly peripherals for sensing, acquisition, storage, processing, and control of physical behavior. However, costly peripherals are no longer necessary to obtain precise measurements and achieve stable feedback control of test-beds. With smartphones performing diverse sensing and processing tasks, this study examines the feasibility of mounting smartphones directly to test-beds to exploit their embedded hardware and software in the measurement and control of the test-beds. This approach is a first step towards replacing laboratory-grade peripherals with more compact and affordable smartphone-based platforms, whose interactive user interfaces can engender wider participation and engagement from learners. Demonstrative cases are presented in which the sensing, computation, control, and user interaction with three motor-based test-beds are handled by a mounted smartphone. Results of experiments and simulations are used to validate the feasibility of mounted smartphones as measurement and feedback control platforms for motor-based laboratory test-beds, report the measurement precision and closed-loop performance achieved with such platforms, and address challenges in the development of platforms to maintain system stability. PMID:27556464

  10. Bed forms created by simulated waves and currents in a large flume

    Science.gov (United States)

    Lacy, Jessica R.; Rubin, David M.; Ikeda, Hiroshi; Mokudai, Kuniyasu; Hanes, Daniel M.

    2007-01-01

    The morphology and evolution of bed forms created by combinations of waves and currents were investigated using an oscillating plate in a 4-m-wide flume. Current speed ranged from 0 to 30 cm/s, maximum oscillatory velocity ranged from 20 to 48 cm/s, oscillation period was 8 s (except for one run with 12 s period), and the median grain size was 0.27 mm. The angle between oscillations and current was 90°, 60°, or 45°. At the end of each run the sand bed was photographed and ripple dimensions were measured. Ripple wavelength was also determined from sonar images collected throughout the runs. Increasing the ratio of current to wave (i.e., oscillatory) velocity decreased ripple height and wavelength, in part because of the increased fluid excursion during the wave period. Increasing the ratio of current to waves, or decreasing the angle between current and waves, increased the three-dimensionality of bed forms. During the runs, ripple wavelength increased by a factor of about 2. The average number of wave periods for evolution of ripple wavelength to 90% of its final value was 184 for two-dimensional ripples starting from a flat bed. Bed form orientations at the end of each run were compared to four potential controlling factors: the directions of waves, current, maximum instantaneous bed shear stress, and maximum gross bed form normal transport (MGBNT). The directions of waves and of MGBNT were equally good predictors of bed form orientations, and were significantly better than the other two factors.

  11. Diffusion Rates and Dispersal Patterns of Unfed versus Recently Fed Bed Bugs (Cimex lectularius L.).

    Science.gov (United States)

    Goddard, Jerome; Caprio, Michael; Goddard, Jerome

    2015-01-01

    Bed bug problems have been increasing since the 1980s, and accordingly, there have been intensive efforts to better understand their biology and behavior for control purposes. Understanding bed bug diffusion rates and dispersal patterns from one site to another (or lack thereof) is a key component in prevention and control campaigns. This study analyzed diffusion rates and dispersal patterns in a population of bed bugs, recently fed and unfed, in both one-dimensional and two-dimensional settings. When placed in the middle of a 71 cm × 2.7 cm artificial lane, approximately half of the bugs regardless of feeding status stayed at or near the release point during the 10 min observation periods, while about a fourth of them walked to the end of the lane. When placed in the middle of an arena measuring 51 cm × 76 cm and allowed to walk in any direction, approximately one-fourth of bed bugs, fed or unfed, still remained near their release point (no significant difference between fed or unfed). As for long-distance dispersal, 11/50 (22%) of recently fed bed bugs moved as far as possible in the arena during the 10 min replications, while only 2/50 (4%) unfed bed bugs moved to the maximum distance. This difference was significantly different (p bed bug movements and an estimated diffusion rate range of 0.00006 cm²/s to 0.416 cm²/s was determined, which is almost no movement to a predicted root mean squared distance of approximately 19 cm per 10 min. The results of this study suggest that bed bugs, upon initial introduction into a new area, would have a difficult time traversing long distances when left alone to randomly disperse. PMID:26466900

  12. A depositional model for the Taylor coal bed, Martin and Johnson counties, eastern Kentucky

    Science.gov (United States)

    Andrews, W.M.; Hower, J.C.; Ferm, J.C.; Evans, S.D.; Sirek, N.S.; Warrell, M.; Eble, C.F.

    1996-01-01

    This study investigated the Taylor coal bed in Johnson and Martin counties, eastern Kentucky, using field and petrographic techniques to develop a depositional model of the coal bed. Petrography and chemistry of the coal bed were examined. Multiple benches of the Taylor coal bed were correlated over a 10 km distance. Three sites were studied in detail. The coal at the western and eastern sites were relatively thin and split by thick clastic partings. The coal at the central site was the thickest and unsplit. Two major clastic partings are included in the coal bed. Each represents a separate and distinct fluvial splay. The Taylor is interpreted to have developed on a coastal plain with periodic flooding from nearby, structurally-controlled fluvial systems. Doming is unlikely due to the petrographic and chemical trends, which are inconsistent with modern Indonesian models. The depositional history and structural and stratigraphic setting suggest contemporaneous structural influence on thickness and quality of the Taylor coal bed in this area.

  13. Fluidized-bed combustion process evaluation and program support. Quarterly report, January-March 1980

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, I.; Podolski, W.F.; Swift, W.M.; Henry, R.F.; Hanway, J.E.; Griggs, K.E.; Herzenberg, C.; Helt, J.E.; Carls, E.L.

    1980-12-01

    Argonne National Laboratory is undertaking several tasks primarily in support of the pressurized fluidized-bed combustion project management team at Morgantown Energy Technology Center. Work is under way to provide fluidized-bed combustion process evaluation and program support to METC, determination of the state of the art of instrumentation for FBC applications, evaluation of the performance capability of cyclones for hot-gas cleaning in PFBC systems, and an initial assessment of methods for the measurement of sodium sulfate dew point.

  14. RIVER BED TOPOGRAPHY IN MEANDERING STREAMS AND ITS RELATIONSHIP WITH LOCAL SCOUR

    Directory of Open Access Journals (Sweden)

    Mahmud GÜNGÖR

    2006-01-01

    Full Text Available In Meandering Streams, deformation in bed topography occurs due to secondary flows. This situation significantly increases the local scour depths around hydraulic structures such as bridge piers and dikes, especially at the central angles of ~60º, ~130º and outer boundaries of the channel. Therefore, it is important to determine bed topography in dealing with local scour depths around hydraulic structures and investigate its effect on scour depths. In this study, bed deformations generated before the construction of hydraulic structure in a channel bend of 180o due to only flow are investigated. For this purpose, a series of experiments were made and bed topography was obtained by measuring the bed elevations at each central angle of 5o. As a result of the experimantal study, scour was not much observed in the beginning of the meander because the meterials coming from the upstream replaces the carried material, but it was observed that the scour depth increases because of the lack of incoming material. The generated relative flow depths were determined at flow axis and along the line which was thought to be at a distance of 20 % of channel width from the channel boundary and bed topography generated by the effect of flow was obtained. As a result, it was observed that the parameters which are effective in the generation of bed topography due to flow at meandering channel have the same effect in the generation of local scour when an obstacle is placed and that the bed topography and local scour depths have a very close similarity.

  15. Using technology for bed management in public hospitals - A strategic analysis and change management plan

    OpenAIRE

    Brayan, Daniel Joseph

    2005-01-01

    As healthcare organisations in New South Wales, Australia, are facing the increased demands of an aging population, new approaches to improving access to services are being sought. This project explores the potential of applying information technology to the management of beds in a large Sydney public hospital. More specifically, this project addresses the cultural and organizational aspects of hospital environments and factors them into a change management plan for implementing bed managemen...

  16. Modeling river dune development and dune transition to upper stage plane bed

    OpenAIRE

    Naqshband, S.; Duin, van, ACT; Ribberink, J.S.; Hulscher, S.J.M.H.

    2016-01-01

    Large asymmetric bedforms known as dunes commonly dominate the bed of sand rivers. Due to the turbulence generation over their stoss and lee sides, dunes are of central importance in predicting hydraulic roughness and water levels. During floods in steep alluvial rivers, dunes are observed to grow rapidly as flow strength increases, undergoing an unstable transition regime, after which they are washed out in what is called upper stage plane bed. This transition of dunes to upper stage plane b...

  17. Flow structure formation and evolution in circulating gas-fluidised beds

    OpenAIRE

    Li, Jie; Kuipers, J.A.M.

    2004-01-01

    The occurrence of heterogeneous flow structures in gas-particle flows seriously affects the gas-solid contacting and transport processes in high-velocity gas-fluidized beds. Particles do not disperse uniformly in the flow but pass through the bed in a swarm of clusters. The so-called "core-annulus" structure in the radial direction and "S" shaped axial distribution of solids concentration characterize the typical flow structure in the system. A computational study, using the discrete particle...

  18. Sea otters homogenize mussel beds and reduce habitat provisioning in a rocky intertidal ecosystem.

    Directory of Open Access Journals (Sweden)

    Gerald G Singh

    Full Text Available Sea otters (Enhydra lutris are keystone predators that consume a variety of benthic invertebrates, including the intertidal mussel, Mytilus californianus. By virtue of their competitive dominance, large size, and longevity, M. californianus are ecosystem engineers that form structurally complex beds that provide habitat for diverse invertebrate communities. We investigated whether otters affect mussel bed characteristics (i.e. mussel length distributions, mussel bed depth, and biomass and associated community structure (i.e. biomass, alpha and beta diversity by comparing four regions that varied in their histories of sea otter occupancy on the west coast of British Columbia and northern Washington. Mussel bed depth and average mussel lengths were 1.5 times lower in regions occupied by otters for >20 years than those occupied for <5 yrs. Diversity of mussel bed associated communities did not differ between regions; however, the total biomass of species associated with mussel beds was more than three-times higher where sea otters were absent. We examined alternative explanations for differences in mussel bed community structure, including among-region variation in oceanographic conditions and abundance of the predatory sea star Pisaster ochraceus. We cannot discount multiple drivers shaping mussel beds, but our findings indicate the sea otters are an important one. We conclude that, similar to their effects on subtidal benthic invertebrates, sea otters reduce the size distributions of intertidal mussels and, thereby, habitat available to support associated communities. Our study indicates that by reducing populations of habitat-providing intertidal mussels, sea otters may have substantial indirect effects on associated communities.

  19. Relationship between the tropical seagrass beds characteristics and the structure of the associated fish community

    OpenAIRE

    Ambo-Rappe, Rohani; Nessa, Muhammad Natsir; Latuconsina, Husain; Dmitry L. LAJUS

    2013-01-01

    Structural complexity of seagrass bed including species composition and shoot density is argued to be an important factor determining fish assemblages. However statistical verification of such a relationship is possible only in areas with high species richness of seagrass and fish assemblages which is observed in tropical waters. Material for this study was collected in three seagrass beds with different structure in Inner Ambon Bay, Eastern Indonesia. This study provided evidence that higher...

  20. Seaweed farming and artisanal fisheries in an Indonesian seagrass bed - complementary or competitive usages?

    OpenAIRE

    Blankenhorn, Sven Uli

    2008-01-01

    In Indonesia, coastal villages traditionally depend on artisanal fisheries. Increasing population density and fishing pressure make alternative sources of income become more important. One possibility is seaweed farming, which has been introduced in many communities. There, algae farming is restricted to shallow waters and their natural ecosystems, e. g. seagrass beds. Seagrass beds themselves are important habitats for many fish species are the basis for fisheries. If seaweed farming causes ...

  1. Onset and cessation of grain motion in fluid-sheared beds

    Science.gov (United States)

    Clark, Abe; Salevan, Julia; Shattuck, Mark; Ouellette, Nick; O'Hern, Corey

    2015-11-01

    We performed molecular dynamics simulations of granular beds driven by a model hydrodynamic shear flow to elucidate general grain-scale mechanisms that determine the onset and cessation of sediment transport. By varying the Shields number (the nondimensional shear stress at the top of the bed) and particle Reynolds number (the ratio of particle inertia to viscous damping), we explore how variations of the fluid flow rate, particle inertia, and fluid viscosity affect the onset and cessation of bed motion. For low to moderate particle Reynolds numbers, a critical boundary separates mobile and static states. Transition times between these states diverge as this boundary is approached both from above and below. At high particle Reynolds number, inertial effects become dominant, and particle motion can be sustained well below flow rates at which mobilization of a static bed occurs. We also find that the onset of bed motion (for both low and high particle Reynolds numbers) is described by Weibullian weakest-link statistics, and thus is crucially dependent on the packing structure of the granular bed, even deep beneath the surface. This work was supported by the US Army Research Office under Grant No. W911NF-14-1-0005.

  2. Production of succinic acid in basket and mobile bed bioreactors-Comparative analysis of substrate mass transfer aspects☆

    Institute of Scientific and Technical Information of China (English)

    Anca-Irina Galaction; Dan Cacaval; Ramona-Mihaela Matran; Alexandra Tucaliuc

    2016-01-01

    The glucose mass transfer in the biosynthesis of succinic acid with immobilized Actinobacil us succinogenes cel s has been comparatively analyzed for a bioreactor with mobile bed vs. a stationary basket bioreactor. The process has been considered to occur under substrate and product inhibitory effects. The results indicated that the biore-actor with mobile bed is more efficient for biocatalyst particles with a diameter over 3 mm, while the basket bio-reactor is more efficient for smal er biocatalyst particles and basket bed thickness below 5 mm. The performances of both configurations of immobilized A. succinogenes cell beds were found to be superior to the column packed bed bioreactor.

  3. The Silurian Reservoir Bed-Differentiated Asphalts in Tarim Basin and Modeling Experiments on Their Origin

    Institute of Scientific and Technical Information of China (English)

    刘洛夫; 刘宏江; 王洪玉; 曾溅辉

    2002-01-01

    There is a type of asphalt that originated from differentiation from reservoir bed (named reservoir bed-differentiated asphalt) in the Silurian asphaltic sandstones of the Tarim Basin. These asphalts are the result of second-time charging of hydrocarbons into the Silurian reservoir, which were derived from Lower Paleozoic source rocks. Asphalt was differentiated from the reservoir bed in the hydrocarbon gathering area of secondary migration. The differen tiation is caused by changes in reservoir physical properties when pearl or chain hydrocarbons migrating through and gathering in the reservoir bed, and light components are lost and heavy ones are involved in the formation of asphalt or heavy oil. There are two kinds of occurrence of these asphalts in the Silurian system of the Tarim Basin. One is the poor heavy oil layer with lower oil saturation in trap and the other is scattered hydrocarbon distributed along the transport layer and unconformity surface. Reservoir bed-differentiated asphalts have two characteristics: total hydrocarbon content is high in extractable organic matter and the ratio of saturated to aromatic hydrocarbon is usually greater than unity. The physically modeling experiment has confirmed these characteristics and the genesis of the reservoir bed-differentiated asphalts.

  4. Positive feedback and momentum growth during debris-flow entrainment of wet bed sediment

    Science.gov (United States)

    Iverson, R.M.; Reid, M.E.; Logan, M.; LaHusen, R.G.; Godt, J.W.; Griswold, J.P.

    2011-01-01

    Debris flows typically occur when intense rainfall or snowmelt triggers landslides or extensive erosion on steep, debris-mantled slopes. The flows can then grow dramatically in size and speed as they entrain material from their beds and banks, but the mechanism of this growth is unclear. Indeed, momentum conservation implies that entrainment of static material should retard the motion of the flows if friction remains unchanged. Here we use data from large-scale experiments to assess the entrainment of bed material by debris flows. We find that entrainment is accompanied by increased flow momentum and speed only if large positive pore pressures develop in wet bed sediments as the sediments are overridden by debris flows. The increased pore pressure facilitates progressive scour of the bed, reduces basal friction and instigates positive feedback that causes flow speed, mass and momentum to increase. If dryer bed sediment is entrained, however, the feedback becomes negative and flow momentum declines. We infer that analogous feedbacks could operate in other types of gravity-driven mass flow that interact with erodible beds. ?? 2011 Macmillan Publishers Limited. All rights reserved.

  5. Cardiovascular control and stabilization via inclination and mobilization during bed rest.

    Science.gov (United States)

    Wieser, Martin; Gisler, Stefan; Sarabadani, Amirehsan; Ruest, Rafael M; Buetler, Lilith; Vallery, Heike; Klamroth-Marganska, Verena; Hund-Georgiadis, Margret; Felder, Morena; Schoenberger, Josef L; Gutknecht, Clemens; Riener, Robert

    2014-01-01

    Cardiovascular deconditioning has long been recognized as a characteristic of the physiological adaptation to long-term bed rest in patients. The process is thought to contribute to orthostatic intolerance and enhance secondary complications in a significant way. Mobilization is a cost-effective and simple method to maintain the cardiovascular parameters (i.e., blood pressure, heart rate) stable, counter orthostatic intolerance and reduce the risk of secondary problems in patients during long-term immobilization. The aim of this project is to control the cardiovascular parameters such as heart rate and blood pressure of bed rest patients via automated leg mobilization and body tilting. In a first step, a nonlinear model predictive control strategy was designed and evaluated on five healthy subjects and 11 bed rest patients. In a next step, a clinically feasible study was conducted on two patients. The mean values differed on average less than 1 bpm from the predetermined heart rate and less than 2.5 mmHg from the desired blood pressure values. These results of the feasibility study are promising, although heterogeneous disease etiologies and individual medication strongly influence the mechanically induced reactions. The long-term goal is an automation of the control of physiological signals and the mobilization of bed rest patients in an early phase of the rehabilitation process. Therefore, this new approach could help to strengthen the cardiovascular system and prevent secondary health problems arising from long-term bed rest.

  6. The Space Station Module Power Management and Distribution automation test bed

    Science.gov (United States)

    Lollar, Louis F.

    1991-01-01

    The Space Station Module Power Management And Distribution (SSM/PMAD) automation test bed project was begun at NASA/Marshall Space Flight Center (MSFC) in the mid-1980s to develop an autonomous, user-supportive power management and distribution test bed simulating the Space Station Freedom Hab/Lab modules. As the test bed has matured, many new technologies and projects have been added. The author focuses on three primary areas. The first area is the overall accomplishments of the test bed itself. These include a much-improved user interface, a more efficient expert system scheduler, improved communication among the three expert systems, and initial work on adding intermediate levels of autonomy. The second area is the addition of a more realistic power source to the SSM/PMAD test bed; this project is called the Large Autonomous Spacecraft Electrical Power System (LASEPS). The third area is the completion of a virtual link between the SSM/PMAD test bed at MSFC and the Autonomous Power Expert at Lewis Research Center.

  7. Burial Records of Reactive Iron in Cretaceous Black Shales and Oceanic Red Beds from Southern Tibet

    Institute of Scientific and Technical Information of China (English)

    HUANG Yongjian; WANG Chengshan; HU Xiumian; CHEN Xi

    2007-01-01

    One of the new directions in the field of Cretaceous research is to elucidate the mechanism of the sedimentary transition from the Cretaceous black shales to oceanic red beds. A chemical sequential extraction method was applied to these two types of rocks from southern Tibet to investigate the burial records of reactive iron. Results indicate that carbonate-associated iron and pyrite are relatively enriched in the black shales, but depleted or absent in red beds. The main feature of the reactive iron in the red beds is relative enrichment of iron oxides (largely hematite), which occurred during syn-depostion or early diagenesis. The ratio between iron oxides and the total iron indicates an oxygen-enriched environment for red bed deposition. A comparison between the reactive iron burial records and proxies of paleo-productivity suggests that paleo-productivity decreases when the ratio between iron oxides and the total iron increases in the red beds. This phenomenon could imply that the relationship between marine redox and productivity might be one of the reasons for the sedimentary transition from Cretaceous black shale to oceanic red bed deposition.

  8. KANSAINVÄLINEN DIAKONIA PAIKALLISSEURAKUNNASSA : Tutkimus kansainvälisestä diakoniasta Suomen evankelis-luterilaisen kirkon paikallisseurakunnissa Espoon hiippakunnan alueella

    OpenAIRE

    Inkinen, Raisa

    2011-01-01

    Inkinen, Raisa. KANSAINVÄLINEN DIAKONIA PAIKALLISSEURAKUNNASSA. Tutkimus kansainvälisestä diakoniasta Suomen evankelis-luterilaisen kirkon paikallisseurakunnissa Espoon hiippakunnan alueella. Järvenpää, kevät 2011. 96 s, 2 liitettä. Diakonia-ammattikorkeakoulu, DIAK Etelä, Järvenpää. Sosiaalialan koulutusohjelma. Diakonia ja nuorisotyö. Sosionomi (ylempi AMK). Opinnäytetyössäni tutkin, mitä on kansainvälinen diakonia paikallisseurakunnassa. Tavoitteena oli tarkastella, miten...

  9. Kahden käden työtä : Lähetys ja kansainvälinen diakonia Länsi-Porin seurakunnan nuorten illoissa

    OpenAIRE

    Lahti, Tiia

    2010-01-01

    Lahti, Tiia. Kahden käden työtä. Lähetys ja kansainvälinen diakonia Länsi-Porin seurakunnan nuorten illoissa. Pori, kevät 2010. 39 sivua. 4 liitettä. Diakonia-ammattikorkeakoulu. Diak Länsi Pori. Sosiaalialan koulutusohjelma. Diakonisen sosiaalityön suuntautumisvaihtoehto, sosionomi (AMK) + diakoni. Opinnäytetyö oli kehittämishanke, joka toteutettiin yhteistyössä Länsi-Porin seurakunnan kanssa. Opinnäytetyön tavoitteena oli saada lähetys ja kansainvälinen diakonia osaksi seurakunnan n...

  10. Pressure-flow relationships for packed beds of compressible chromatography media at laboratory and production scale.

    Science.gov (United States)

    Stickel, J J; Fotopoulos, A

    2001-01-01

    Pressure drop across chromatography beds employing soft or semirigid media can be a significant problem in the operation of large-scale preparative chromatography columns. The shape or aspect ratio (length/diameter) of a packed bed has a significant effect on column pressure drop due to wall effects, which can result in unexpectedly high pressures in manufacturing. Two types of agarose-based media were packed in chromatography columns at various column aspect ratios, during which pressure drop, bed height, and flow rate were carefully monitored. Compression of the packed beds with increasing flow velocities was observed. An empirical model was developed to correlate pressure drop with the aspect ratio of the packed beds and the superficial velocity. Modeling employed the Blake-Kozeny equation in which empirical relationships were used to predict bed porosity as a function of aspect ratio and flow velocity. Model predictions were in good agreement with observed pressure drops of industrial scale chromatography columns. A protocol was developed to predict compression in industrial chromatography applications by a few laboratory experiments. The protocol is shown to be useful in the development of chromatographic methods and sizing of preparative columns.

  11. Heat-transfer characteristics of flowing and stationary particle-bed-type fusion-reactor blankets

    Energy Technology Data Exchange (ETDEWEB)

    Nietert, R.E.

    1983-02-01

    The heat-transfer characteristics of flowing and stationary packed-particle beds have recently become of interest in connection with conceptual designs of fusion reactor blankets. A detailed literature survey has shown that the processes taking place in such beds are not fully understood despite their widespread use in the chemical industry and other engineering disciplines for more than five decades. In this study, two experimental investigations were pursued. In the first, a heat-transfer loop was constructed through which glass microspheres were allowed to flow by rgravity at controlled rates through an electrically heated stainless steel tubular test section. In the second, an annular packed bed was constructed in which heat was applied through the outer wall by electric heating of a stainless steel tube. Cooling occurred at the inner wall of the annular bed by flowing air through the central tube. A second air stream was allowed to flow through the voids of the packed bed. An error-minimization technique was utilized in order to obtain the two-dimensional one-parameter effective conductivity for the bed by comparing the experimental and theoretically predicted temperature profiles. Experiments were conducted for various modified Reynolds numbers less than ten.

  12. Heat-transfer characteristics of flowing and stationary particle-bed-type fusion-reactor blankets

    International Nuclear Information System (INIS)

    The heat-transfer characteristics of flowing and stationary packed-particle beds have recently become of interest in connection with conceptual designs of fusion reactor blankets. A detailed literature survey has shown that the processes taking place in such beds are not fully understood despite their widespread use in the chemical industry and other engineering disciplines for more than five decades. In this study, two experimental investigations were pursued. In the first, a heat-transfer loop was constructed through which glass microspheres were allowed to flow by rgravity at controlled rates through an electrically heated stainless steel tubular test section. In the second, an annular packed bed was constructed in which heat was applied through the outer wall by electric heating of a stainless steel tube. Cooling occurred at the inner wall of the annular bed by flowing air through the central tube. A second air stream was allowed to flow through the voids of the packed bed. An error-minimization technique was utilized in order to obtain the two-dimensional one-parameter effective conductivity for the bed by comparing the experimental and theoretically predicted temperature profiles. Experiments were conducted for various modified Reynolds numbers less than ten

  13. Effects of Bed Rest on Conduction Velocity of the Triceps Surae Stretch Reflex and Postural Control

    Science.gov (United States)

    Reschke, M. F.; Wood, S. J.; Cerisano, J. M.; Kofman, I. S.; Fisher, E. A.; Esteves, J. T.; Taylor, L. C.; DeDios, Y. E.; Harm, D. L.

    2011-01-01

    Despite rigorous exercise and nutritional management during space missions, astronauts returning from microgravity exhibit neuromuscular deficits and a significant loss in muscle mass in the postural muscles of the lower leg. Similar changes in the postural muscles occur in subjects participating in long-duration bed rest studies. These adaptive muscle changes manifest as a reduction in reflex conduction velocity during head-down bed rest. Because the stretch reflex encompasses both the peripheral (muscle spindle and nerve axon) and central (spinal synapse) components involved in adaptation to calf muscle unloading, it may be used to provide feedback on the general condition of neuromuscular function, and might be used to evaluate the effectiveness of countermeasures aimed at preserving muscle mass and function during periods of unloading. Stretch reflexes were measured on 18 control subjects who spent 60 to 90 days in continuous 6 deg head-down bed rest. Using a motorized system capable of rotating the foot around the ankle joint (dorsiflexion) through an angle of 10 degrees at a peak velocity of about 250 deg/sec, a stretch reflex was recorded from the subject's left triceps surae muscle group. Using surface electromyography, about 300 reflex responses were obtained and ensemble-averaged on 3 separate days before bed rest, 3 to 4 times in bed, and 3 times after bed rest. The averaged responses for each test day were examined for reflex latency and conduction velocity (CV) across gender. Computerized posturography was also conducted on these same subjects before and after bed rest as part of the standard measures. Peak-to-peak sway was measured during Sensory Organization Tests (SOTs) to evaluate changes in the ability to effectively use or suppress visual, vestibular, and proprioceptive information for postural control. Although no gender differences were found, a significant increase in reflex latency and a significant decrease in CV were observed during the bed

  14. Numerical evaluation of the effects of planform geometry and inflow conditions on flow, turbulence structure, and bed shear velocity at a stream confluence with a concordant bed

    Science.gov (United States)

    Constantinescu, George; Miyawaki, Shinjiro; Rhoads, Bruce; Sukhodolov, Alexander

    2014-10-01

    This study numerically investigates the effects of variations in inflow conditions and planform geometry on large-scale coherent flow structures and bed friction velocities at a stream confluence with natural bathymetry and concordant bed morphology. Several numerical experiments are conducted in which either the Kelvin-Helmholtz mode or the wake mode dominates within the mixing interface (MI) between the two confluent streams as the junction angle and alignments of the tributaries are altered. In the Kelvin-Helmholtz mode, the MI contains mostly corotating vortices driven by the mean transverse shear across the MI, while in the wake mode the MI contains counterrotating vortices forming by the interaction of the separated shear layers on the two sides of a zone of stagnant fluid near the junction corner. A large angle between the two incoming streams is not necessary for the development of strongly coherent streamwise-oriented vortical (SOV) cells in the immediate vicinity of the MI. Results show that such SOV cells can develop and produce high bed friction velocities even for cases with a low angle between the two tributaries and for cases where the downstream channel is approximately aligned with the axes of the two tributaries (low-curvature cases). SOV cells tend not to develop only when the incoming streams are parallel and aligned with the downstream channel (junction angle of zero), and the incoming flows produce a strong Kelvin-Helmholtz mode. Under such conditions, quasi 2-D MI vortices play the primary role in mixing and the production of high bed shear velocities. Simulations with and without natural bed morphology/local bank line irregularities indicate that planform geometry and inflow conditions primarily govern the development of coherent flow structures, but that bathymetric and bank line effects can locally modify details of these structures.

  15. Bed In Summer

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    In winter I get up at night And dress by yellow candle-light. In summer, quite the other way, I have to go to bed by day. I have to go to bed and see The birds still hopping on the tree, Or hear the grown-up people' s feet Still going past me in the stree

  16. Fluidized bed incinerator development

    International Nuclear Information System (INIS)

    A fluidized bed incinerator is being developed for burning rad contaminated solid and liquid waste materials. In situ neutralization of acid gases by the bed material, catalytic afterburning, and gas filtration are used to produce a clean flue gas without the use of aqueous scrubbing

  17. Pattern formation in vibrated beds of dry and wet granular materials

    Science.gov (United States)

    Chuan Lim, Eldin Wee

    2014-01-01

    The Discrete Element Method was coupled with a capillary liquid bridge force model for computational studies of pattern formation in vibrated granular beds containing dry or wet granular materials. Depending on the vibration conditions applied, hexagonal, stripes, or cellular pattern was observed in the dry vibrated granular bed. In each of these cases, the same hexagonal, stripes, or cellular pattern was also observed in the spatial distribution of the magnitudes of particle-particle collision forces prior to the formation of the corresponding actual pattern in physical distributions of the particles. This seemed to suggest that the pattern formation phenomenon of vibrated granular bed systems might be the result of a two-dimensional Newton's cradle effect. In the presence of a small amount of wetness, these patterns were no longer formed in the vibrated granular beds under the same corresponding set of vibration conditions. Despite the relatively much weaker capillary forces arising from the simulated liquid bridges between particles compared with particle-particle collision forces, the spatial distributions of these collision forces, physical distributions of particles, as well as time profiles of average collision forces were altered significantly in comparison with the corresponding distributions and profiles observed for the dry vibrated granular beds. This seemed to suggest the presence of a two-dimensional Stokes' cradle effect in these wet vibrated granular bed systems which disrupted the formation of patterns in the wet granular materials that would have been observed in their dry counterparts.

  18. The COOLOCE experiments investigating the dryout power in debris beds of heap-like and cylindrical geometries

    Energy Technology Data Exchange (ETDEWEB)

    Takasuo, Eveliina, E-mail: eveliina.takasuo@vtt.fi [VTT Technical Research Centre of Finland, P.O. Box 1000, 02044 VTT, Espoo (Finland); Holmstroem, Stefan; Kinnunen, Tuomo; Pankakoski, Pekka H. [VTT Technical Research Centre of Finland, P.O. Box 1000, 02044 VTT, Espoo (Finland)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer We investigate the effect of geometry on the coolability of porous core debris beds. Black-Right-Pointing-Pointer Dryout power is measured for a heap-like (conical) and a cylindrical debris bed. Black-Right-Pointing-Pointer The coolability of the cylindrical bed is better due to the lower height of the configuration. - Abstract: The COOLOCE test facility has been used for experimental investigations of the coolability of porous core debris beds with different geometries. The main objective of the experiments was to compare the dryout behavior of conical (heap-like) and top-flooded cylindrical (evenly distributed) debris bed configurations in order to investigate the effect of geometry on the coolability of the debris bed. The experimental debris beds simulate the possible outcomes of melt discharge from the reactor pressure vessel and the formation of a core debris bed in a deep water pool during a severe accident. The results suggest that if the two debris bed configurations have equal height, the coolability of the conical bed is improved compared to the cylindrical bed due to the multi-dimensional infiltration of water through the surface of the cone. However, in case the conical and cylindrical debris beds have equal diameter and volume, the dryout power density of the conical configuration is lower than that of the cylindrical configuration by approximately 50%. This is due to the greater height of the conical configuration which leads to increased heat flux in the upper parts of the conical debris bed. According to the present results, the effect of the increased debris bed height is greater than the effect of multi-dimensional flooding. Simulations show the differences between the two-phase flow behavior of the two geometries, and the resulting difference in dryout development.

  19. The COOLOCE experiments investigating the dryout power in debris beds of heap-like and cylindrical geometries

    International Nuclear Information System (INIS)

    Highlights: ► We investigate the effect of geometry on the coolability of porous core debris beds. ► Dryout power is measured for a heap-like (conical) and a cylindrical debris bed. ► The coolability of the cylindrical bed is better due to the lower height of the configuration. - Abstract: The COOLOCE test facility has been used for experimental investigations of the coolability of porous core debris beds with different geometries. The main objective of the experiments was to compare the dryout behavior of conical (heap-like) and top-flooded cylindrical (evenly distributed) debris bed configurations in order to investigate the effect of geometry on the coolability of the debris bed. The experimental debris beds simulate the possible outcomes of melt discharge from the reactor pressure vessel and the formation of a core debris bed in a deep water pool during a severe accident. The results suggest that if the two debris bed configurations have equal height, the coolability of the conical bed is improved compared to the cylindrical bed due to the multi-dimensional infiltration of water through the surface of the cone. However, in case the conical and cylindrical debris beds have equal diameter and volume, the dryout power density of the conical configuration is lower than that of the cylindrical configuration by approximately 50%. This is due to the greater height of the conical configuration which leads to increased heat flux in the upper parts of the conical debris bed. According to the present results, the effect of the increased debris bed height is greater than the effect of multi-dimensional flooding. Simulations show the differences between the two-phase flow behavior of the two geometries, and the resulting difference in dryout development.

  20. Fluidized bed calciner apparatus

    Science.gov (United States)

    Owen, Thomas J.; Klem, Jr., Michael J.; Cash, Robert J.

    1988-01-01

    An apparatus for remotely calcining a slurry or solution feed stream of toxic or hazardous material, such as ammonium diurante slurry or uranyl nitrate solution, is disclosed. The calcining apparatus includes a vertical substantially cylindrical inner shell disposed in a vertical substantially cylindrical outer shell, in which inner shell is disposed a fluidized bed comprising the feed stream material to be calcined and spherical beads to aid in heat transfer. Extending through the outer and inner shells is a feed nozzle for delivering feed material or a cleaning chemical to the beads. Disposed in and extending across the lower portion of the inner shell and upstream of the fluidized bed is a support member for supporting the fluidized bed, the support member having uniform slots for directing uniform gas flow to the fluidized bed from a fluidizing gas orifice disposed upstream of the support member. Disposed in the lower portion of the inner shell are a plurality of internal electric resistance heaters for heating the fluidized bed. Disposed circumferentially about the outside length of the inner shell are a plurality of external heaters for heating the inner shell thereby heating the fluidized bed. Further, connected to the internal and external heaters is a means for maintaining the fluidized bed temperature to within plus or minus approximately 25.degree. C. of a predetermined bed temperature. Disposed about the external heaters is the outer shell for providing radiative heat reflection back to the inner shell.

  1. Development of Bed Ridges in Open Channels and their Effects on Secondary Currents and Wall Shear

    Directory of Open Access Journals (Sweden)

    Kamran Ansari

    2012-07-01

    Full Text Available A numerical analysis of the ridges on the bed of wide, open channels and their effects on the distribution of secondary currents and wall shear is undertaken using CFD (Computational Fluid Dynamics. The presence of the lines of boil, consisting of low speed streaks, periodically in the transverse direction, is reported in the literature due to the presence of the ridges. In the present work, simulations are run on channel sections with varying the number of ridges on the bed and the size of these ridges. The effect of these variations on the flow structures and shear stress distribution in wide open channels is reported. The results offer an interesting insight into the 3D (Three-Dimensional flow structures involved and the link between flow structures and bed morpho-dynamics in prismatic channels.

  2. Together and apart: twin beds, domestic hygiene and modern marriage, 1890-1945.

    Science.gov (United States)

    Hinds, Hilary

    2010-01-01

    This article examines the advent of twin beds as a common sleeping arrangement for English couples. Through an analysis of a range of sources from the late nineteenth to mid twentieth centuries - marketing materials, advertisements, domestic, decorative and marital advice books and novels and films - it argues that while twin beds were initially recommended by proponents of the domestic sanitation movement as part of a raft of hygiene measures, by the 1920s they had become a fashionable item of bedroom furniture for modern couples in "companionate" marriages. It was in this context that Marie Stopes, in her popular marital advice books, railed against them as an "invention of the devil", symptomatic of the evils of modernity, and endangering the happiness of the modern married couple. The article concludes that, despite these changing contexts of consumption, the significance of the history of twin beds needs to be understood through the intersecting discourses of domesticity, health and sexuality.

  3. Operation of magnetically assisted fluidized beds in microgravity and variable gravity: experiment and theory

    Science.gov (United States)

    Sornchamni, T.; Jovanovic, G. N.; Reed, B. P.; Atwater, J. E.; Akse, J. R.; Wheeler, R. R.

    2004-01-01

    The conversion of solid waste into useful resources in support of long duration manned missions in space presents serious technological challenges. Several technologies, including supercritical water oxidation, microwave powered combustion and fluidized bed incineration, have been tested for the conversion of solid waste. However, none of these technologies are compatible with microgravity or hypogravity operating conditions. In this paper, we present the gradient magnetically assisted fluidized bed (G-MAFB) as a promising operating platform for fluidized bed operations in the space environment. Our experimental and theoretical work has resulted in both the development of a theoretical model based on fundamental principles for the design of the G-MAFB, and also the practical implementation of the G-MAFB in the filtration and destruction of solid biomass waste particles from liquid streams.

  4. Theoretical and experimental investigation on the transient coupled heat and mass transfer in a radial flow desiccant packed bed

    International Nuclear Information System (INIS)

    Highlights: ► We present theoretical and experimental investigation of desiccant bed. ► Transient coupled heat and mass transfer in a radial flow desiccant packed bed has been reported. ► A real-time model is used. ► The prediction of air exit conditions from the bed is carried out. - Abstract: Theoretical and experimental investigation on the transient coupled heat and mass transfer in a radial flow desiccant packed bed has been reported in the present work. An experimental test rig has been designed and constructed to carry out the required experimental measurements. System parameters and flowing air conditions (bed weight, air velocity, air conditions – dry and wet bulb temperatures- at exit of test rig components) are measured and analyzed. A hollow cylindrical packed bed has been used as a desiccant dehumidifier. This configuration decreases the required power to blow air through the bed. In the theoretical study, prediction of air exit conditions from the bed is carried out based on the model of Barlow for the analysis of adsorption and regeneration processes in the desiccant bed. This model uses simple effectiveness equations for steady-state heat and mass exchangers within a finite difference procedure. Air at different conditions of temperature and humidity enters the regenerated bed and the exit temperature and humidity are plotted with time. Acceptable agreement is found between the theoretical and experimental results. The most effective parameters on the system performance are the initial water content of the bed and its initial temperature. Bed cooling during adsorption improves the system performance.

  5. Quantifying the effects of hydrograph shape and flow transience on coarse sediment bed load transport

    Science.gov (United States)

    Phillips, Colin; Hill, Kimberly; Paola, Chris

    2016-04-01

    The rate of bed load transport under steady flow is known to vary both spatially and temporally due to various hydrologic and granular phenomena. Grain size distributions and riverbed properties (packing, armoring, imbrication, etc.) have been observed to affect flux for a particular value of applied flow stress while hydrology is mainly assumed to control the magnitude of the applied bed stress above the threshold for bed material entrainment. The prediction and measurement of bed load sediment transport in field settings are further complicated by the inherent transience in the flood hydrograph, but relatively little is known about how flood transience differs from a steady flow. Here we investigate the role of flood transience for gravel bed load transport through controlled laboratory experiments in a 28 m long 0.5-meter wide flume. We explore transient flow through the use of short duration hydrographs as the combination of unsteady and intermittent flow, where unsteady flow varies in magnitude over a given duration, and intermittent flow is characterized by turning the flow on and off. Experimental runs consist of sequences of steady and unsteady flood hydrographs of various shapes, but equivalent integrated excess transport capacity. These flood sequences are run for a variety of competent flow durations and peak stress magnitudes. We find that even for a narrow unimodal grain size distribution and constant sediment supply we observe clockwise hysteresis in bed load flux, different thresholds for entrainment and distrainment for the rising and falling limbs of a flood, and a threshold of entrainment that can vary from one flood hydrograph to the next. Despite complex transport phenomena at the particle scale, we find that the total bed load transported for each flood plots along a linear trend with the integrated excess transport capacity, in agreement with prior field results. These experiments indicate that while the effects of transient flow and

  6. Biochemical and hormonal changes in endurance trained volunteers during and after exposure to bed rest and chronic hyperhydration

    Science.gov (United States)

    Zorbas, Y. G.; Naexu, K. A.; Yaroshenko, Y. N.

    2000-04-01

    The objective of this investigation was to assess the effect of a daily intake of fluid and salt supplementation on biochemical and hormonal changes in endurance trained volunteers aged 19-24 yrs during 30-day bed rest and during 15 days of post bed rest period. The studies were performed on 30 long distance runners aged 19-24 yrs who had a peak oxygen uptake of 66 ml/kg/min and had taken 14.5 km/day on average prior to their participation in the study. The volunteers were divided into three groups: the volunteers in the first group were under normal ambulatory conditions (control subjects); the second group subjected to bed rest alone unsupplemented (bed rested volunteers); the third group was submitted to bed rest and consumed daily 30 ml water/kg bodyweight and 0.1 g of sodium chloride (NaCl)/kg body weight (supplemented bed rested volunteers). The second and third groups of volunteers were kept under a rigorous bed rest regime for 30 days. During the pre bed rest period of 15 days, during the bed rest period of 30 days and during the post bed rest period of 15 days cyclic adenosine monophosphate, cyclic guanosine monophosphate, prostaglandins of pressor, prostaglandins depressor groups, renin activity in plasma and aldosterone in plasma and in urine were determined. We found that in bed rested volunteers without fluid and salt supplementation intake plasma renin activity and aldosterone in plasma and urine continued to increase during the bed rest period as plasma volume decreased. Moreover, in this group, cyclic nucleotides measured as an indicator of adrenosympathetic system activity increased and prostaglandins as local vasoactive substances decreased during the bed rest period. These variables returned toward the baselines in the post bed rest period as plasma volume deficit was restituted. On the other hand, the hormonal levels in the other two groups remained rather constant during the experimental period. We concluded that daily intake of fluid and salt

  7. Communication of bed allocation decisions in a critical care unit and accountability for reasonableness

    Directory of Open Access Journals (Sweden)

    Swota Alissa H

    2005-10-01

    Full Text Available Abstract Background Communication may affect perceptions of fair process for intensive care unit bed allocation decisions through its impact on the publicity condition of accountability for reasonableness. Methods We performed a qualitative case study to describe participant perceptions of the communication of bed allocation decisions in an 18-bed university affiliated, medical-surgical critical care unit at Sunnybrook and Women's College Health Sciences Centre. Interviewed participants were 3 critical care physicians, 4 clinical fellows in critical care, 4 resource nurses, 4 "end-users" (physicians who commonly referred patients to the unit, and 3 members of the administrative staff. Median bed occupancy during the study period (Jan-April 2003 was 18/18; daily admissions and discharges (median were 3. We evaluated our description using the ethical framework "accountability for reasonableness" (A4R to identify opportunities for improvement. Results The critical care physician, resource nurse, critical care fellow and end-users (trauma team leader, surgeons, neurosurgeons, anesthesiologists functioned independently in unofficial "parallel tracks" of bed allocation decision-making; this conflicted with the official designation of the critical care physician as the sole authority. Communication between key decision-makers was indirect and could exclude those affected by the decisions; notably, family members. Participants perceived a lack of publicity for bed allocation rationales. Conclusion The publicity condition should be improved for critical care bed allocation decisions. Decision-making in the "parallel tracks" we describe might be unavoidable within usual constraints of time, urgency and demand. Formal guidelines for direct communication between key participants in such circumstances would help to improve the fairness of these decisions.

  8. Magnetostratigraphy-based astronomical tuning of the early Pliocene lacustrine sediments of Ptolemais (NW Greece) and bed-to-bed correlation with the marine record

    NARCIS (Netherlands)

    Vugt, N. van; Steenbrink, J.; Langereis, C.G.; Hilgen, F.J.; Meulenkamp, J.E.

    2001-01-01

    Continental deposits from the early Pliocene lacustrine Ptolemais basin in NW Greece display rhythmical alternations of lignite and marl beds. Three parallel sections from this area are studied using magnetostratigraphy and cyclostratigraphy. The presence of the greater part of the Gilbert Chron ena

  9. Dual-Fuel Fluidized Bed Combustor Prototype for Residential Heating: Steady-State and Dynamic Behavior

    Science.gov (United States)

    Cammarota, Antonio; Chirone, Riccardo; Miccio, Michele; Sollmene, Roberto; Urcluohr, Massimo

    Fluidized bed combustion of biogenic fuels can be recognized as an attractive option for an ecologically sustainable use of biofuels in residential applications. Nevertheless, biomass combustion in fluidized bed reactors presents some drawbacks that are mainly related to mixing/segregation of fuel particles/volatile matter during devolatilization inside the bed and in the freeboard or to bed agglomeration. A prototype of a 30-50 kWth fluidized bed boiler for residential heating has been designed to burn either a gaseous combustible or a solid biomass fuel or both fuels at the same time. The prototype has been equipped with a gas burner located in the wind-box to optimize the start-up stage of the boiler and with a fluidized bed characterized by a conical geometry ("Gulf Stream" circulation) to improve the mixing of the fuel particles during both devolatilization and char burn-out. The operation of the combustor adopting wood pellets as fuel has been investigated to evaluate their use in residential combustion applications. Steady-state thermally stable regimes of operation have been recognized analyzing both boiler temperatures and gaseous emissions. The optimization of the steady-state operation of the boiler in terms of gaseous emissions has been achieved by varying the nominal thermal power and air excess. An ad-hoc experimental campaign has been carried out to analyze the dynamic performance of the prototype as a response to changes of the demanded thermal power. On the basis of the experimental data, an interpretation of the dynamic behavior of the fluidized bed boiler has been proposed.

  10. Getting Rid of Bed Bugs

    Science.gov (United States)

    ... how you select a company. Related Information Collaborative Strategy on Bed Bugs - highlights ways that all levels of government, community, academia and private industry can work together to reduce bed bugs across ...

  11. Comparative study of fluidized-bed and fixed-bed reactor for syngas methanation over Ni-W/TiO2-SiO2catalyst

    Institute of Scientific and Technical Information of China (English)

    Bo; Liu; Shengfu; Ji

    2013-01-01

    In this work,syngas methanation over Ni-W/TiO2-SiO2catalyst was studied in a fluidized-bed reactor(FBR)and its performance was compared with a fixed-bed reactor(FIXBR).The effects of main operating variables including feedstock gases space velocity,coke content,bed temperature and sulfur-tolerant stability of 100 h life were investigated.The structure of the catalysts was characterized by XRD,N2adsorptiondesorption and TEM.It is found that under same space velocity from 5000 h 1to 25000 h 1FBR gave a higher CH4yield,lower coke content,and lower bed temperature than those obtained in FIXBR.Ni-W/TiO2-SiO2catalyst possessed excellent sulfur-tolerant stability on the feedstock gases less than 500 ppm H2S in FBR.The carbon deposits formed on the spent catalyst were in the form of carbon fibers in FBR,while in the form of dense accumulation distribution appearance in FIXBR.

  12. Systematic reviews of bed rest and advice to stay active for acute low back pain.

    Science.gov (United States)

    Waddell, G; Feder, G; Lewis, M

    1997-01-01

    BACKGROUND: In the United Kingdom (UK), 9% of adults consult their doctor annually with back pain. The treatment recommendations are based on orthopaedic teaching, but the current management is causing increasing dissatisfaction. Many general practitioners (GPs) are confused about what constitutes effective advice. AIM: To review all randomized controlled trials of bed rest and of medical advice to stay active for acute back pain. METHOD: A systematic review based on a search of MEDLINE and EMBASE from 1966 to April 1996 with complete citation tracking for randomized controlled trials of bed rest or medical advice to stay active and continue ordinary daily activities. The inclusion criteria were: primary care setting, patients with low back pain of up to 3 months duration, and patient-centred outcomes (rate of recovery from the acute attack, relief of pain, restoration of function, satisfaction with treatment, days off work and return to work, development of chronic pain and disability, recurrent attacks, and further health care use). RESULTS: Ten trials of bed rest and eight trials of advice to stay active were identified. Consistent findings showed that bed rest is not an effective treatment for acute low back pain but may delay recovery. Advice to stay active and to continue ordinary activities results in a faster return to work, less chronic disability, and fewer recurrent problems. CONCLUSION: A simple but fundamental change from the traditional prescription of bed rest to positive advice about staying active could improve clinical outcomes and reduce the personal and social impact of back pain. PMID:9474831

  13. Equivalent materials simulation experimental study on bed separations developing and mining subsidence in constant humidity and constant temperature conditions

    Institute of Scientific and Technical Information of China (English)

    FU Zhi-liang; WANG Su-hua; GAO Yan-fa

    2008-01-01

    A new experiment was made on the developing of bed separations and mining subsidence from Tangshan T2192 working face by equivalent materials simulation.The overburden deformation and the developing of bed separations with working face advancing was simulated by a new model.The results show that the maximum value of bed separations moved forward gradually along with the working face advancing; the maximum value of bed separations is 0.31~0.50 times of mining thickness.The key strata have a great influence upon surface subsidence during the overburden movement process.The mechanics parameters of new experiment are fitted with results in fields perfectly.

  14. The effect of different methods of seed bed preparation on greenhouse cucumber yield and yield components

    Directory of Open Access Journals (Sweden)

    D. Momeni

    2010-12-01

    Full Text Available To investigate the effects of different methods of seed bed preparation on yield of greenhouse cucumber, a two-year long experiment was conducted as a randomized complete block design with four replications in Jiroft from 2004. Different methods of seed bed preparation were as follows: 1 ridge with 20 cm height and 50 cm width and 2 plant rows with 40 cm distance, 2 furrow with 20 cm depth and 50 cm width and 2 plant rows inside, with 40 cm distance, and 3 planting on flat area with 40 cm distance. The results showed that the effect of planting bed on yield of greenhouse cucumber was significant. Furrow and flat area increased yield significantly, compared to the ridge treatment. Analysis of yield components such as plant height, number of pickling fruits, number of leaves, photosynthetic area and number of flowers showed that they are all correlated with fruit yield. The number of pickling fruits was significantly more in furrow and flat area than in ridge treatment. The height of cucumber plants on flat bed was significantly higher than that of the other treatments. The number of leaves and photosynthetic area of plants on flat bed were significantly greater than those in the other treatments. The least dead plants due to fungi disease were observed in ridge treatment. In view of yield and its components under the condition of this experiment, it can be concluded that flat area and furrow treatments are better than ridge treatment.

  15. Fluid-particle interaction and generation of coherent structures over permeable beds: an experimental analysis

    Science.gov (United States)

    Corvaro, Sara; Miozzi, Massimo; Postacchini, Matteo; Mancinelli, Alessandro; Brocchini, Maurizio

    2014-10-01

    We study the dynamics of the oscillatory bottom boundary layer (BBL) that develops at a porous bed under the action of propagating water waves (also known as “ventilated BBL”). In particular, experimental tests of a ventilated BBL generated over a permeable bed made of regular plastic spheres are analysed. With the purpose of characterizing typical dynamics of nearshore waves evolving over dissipative seabeds, we focus on one specific forcing condition, characterized by large nonlinearities and vorticity generation, and expect that such dynamics be qualitatively similar also for other wave regimes. Particle tracking enables an accurate definition of the hydrodynamics generated over the porous medium with specific focus on Eulerian velocity and vorticity fields and on Lagrangian particle trajectories. Nearbed velocity components are strongly influenced by the bed configuration (sphere caps) and are characterized by small-scale oscillations due to the presence of coherent structures over the interstices. Counter-rotating vortex sheets are generated and evolve during the entire wave period; their thickness grows rapidly when flow injection from the bed occurs, while it remains constant under the influence of in-bed flow suction. The evolution of near-bed particles is influenced by strain or vortex-dominated regions. When the intensity of the vortices just outside the BBL is large (generally after flow inversion), the momentum associated to the rotation of the lower layer of vortices in the BBL is comparable with that of the passive tracers, hence the particles are captured and their original trajectories are modified, jumping to a different layer. On the contrary when strain regions are dominant, particles are restricted in the same vorticity layer until sweep or ejection turbulent processes are observed and anomalous particle transport occurs from lower to higher vortex layers and vice versa. The latter occurs during the entire wave cycle, becoming the dominant

  16. Granular-bed and ceramic candle filters in commercial plants: A comparison

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, K.B.; Haas, J.C.; Eshelman, M.B.

    1993-04-01

    Advanced coal fired power cycles require the removal of coal ash at high temperature and pressure. Granular-bed and ceramic candle filters can be used for this service. Conceptual designs for commercial size applications are made for each type of filter. The filters are incorporated in the design of a Foster Wheeler 450 MWe second generation pressurized fluidized bed combustion plant which contains a pressurized fluidized combustor and carbonizer. In a second application, the inters are incorporated in the design of a 100 MWe KRW (air) gasifier based power plant. The candle filter design is state of the art as determined from the open literature with an effort to minimize the cost. The granular-bed filter design is based on test work performed at high temperature and low pressure, tests at New York University performed at high pressure and temperate, and new analysis used to simplify the scale up of the filter and reduce overall cost. The incorporation of chemically reactive granites in the granular-bed filter for the removal of additional coal derived contaminants such as alkali or sulfur is considered. The conceptual designs of the granular-bed inter and the ceramic candle filter are compared in terms of the cost of electricity, capital cost, and operating and maintenance costs for each application.

  17. Maximum spoutable bed height of spout-fluid bed

    Energy Technology Data Exchange (ETDEWEB)

    Wenqi Zhong; Mingyao Zhang; Baosheng Jin [Southeast University, Nanjing (China). Key Laboratory on Clean Coal Power Generation and Combustion Technology of Ministry of Education

    2006-11-15

    Experimental study on the maximum spoutable bed height of a spout-fluid bed (cross-section of 0.3 m x 0.03 m and height of 2 m) packed with Geldart group D particles has been carried out. The effects of particle size, spout nozzle size and fluidizing gas flow rate on the maximum spoutable bed height were studied. Experimental data were compared to some published experiments and predictions. The results show that the maximum spoutable bed height of spout-fluid bed decreases with increasing particle size and spout nozzle size, which appears the same trend to that of spouted beds. The increasing of fluidizing gas flow rate leads to a sharply decrease in the maximum spoutable bed height. The existent correlations of the maximum spoutable bed height in the literature were observed to involve large discrepancies. Additionally, the flow characteristics when bed materials deeper than the maximum spoutable height were summarized. Under this condition, the spout-fluid bed operated without a stable and coherent spout or fountain assembles the characteristics of jetting fluidized bed. Besides, the mechanisms of spout termination were investigated. It was found that slugging in the spout and growth of instabilities would cause the spout termination in spout-fluid bed.

  18. Ice stream motion facilitated by a shallow-deforming and accreting bed.

    Science.gov (United States)

    Spagnolo, Matteo; Phillips, Emrys; Piotrowski, Jan A; Rea, Brice R; Clark, Chris D; Stokes, Chris R; Carr, Simon J; Ely, Jeremy C; Ribolini, Adriano; Wysota, Wojciech; Szuman, Izabela

    2016-01-01

    Ice streams drain large portions of ice sheets and play a fundamental role in governing their response to atmospheric and oceanic forcing, with implications for sea-level change. The mechanisms that generate ice stream flow remain elusive. Basal sliding and/or bed deformation have been hypothesized, but ice stream beds are largely inaccessible. Here we present a comprehensive, multi-scale study of the internal structure of mega-scale glacial lineations (MSGLs) formed at the bed of a palaeo ice stream. Analyses were undertaken at macro- and microscales, using multiple techniques including X-ray tomography, thin sections and ground penetrating radar (GPR) acquisitions. Results reveal homogeneity in stratigraphy, kinematics, granulometry and petrography. The consistency of the physical and geological properties demonstrates a continuously accreting, shallow-deforming, bed and invariant basal conditions. This implies that ice stream basal motion on soft sediment beds during MSGL formation is accommodated by plastic deformation, facilitated by continuous sediment supply and an inefficient drainage system. PMID:26898399

  19. Waste Water Treatment-Bed of Coal Fly Ash for Dyes and Pigments Industry

    International Nuclear Information System (INIS)

    The highly porous power plant waste ashes have been utilized to treat toxic effluent of a dyes manufacturing plant. An attempt has been made for the first time in Pakistan, to generate an effective and economically sound treatment facility for the toxic effluent of a dyes manufacturing plant. This is an indigenous bed which could replace expensive treatment facilities, such as reverse osmosis (RO), granulated activated carbon (GAC) bed, etc. The treatment efficiency was improved by coupling coagulants with fly ash adsorbent bed. The ash was collected from coal fired boilers of power plant at Lakhra Power Generation Company, Jamshoro, Pakistan. The use of this ash resolved the disposal and environmental issues by treating wastewater of chemical, dyes and pigment industry. The treatment bed comprised of briquettes of coal fly ash coupled with commercial coagulant ferrous sulfate-lime reduced COD, color, turbidity and TSS of effluent remarkably. An adsorption capacity and chemical behavior of fly ash bed was also studied. In coagulation treatment, coagulant FeSO/sun 4/-lime influenced reduction of COD, color, turbidity and TSS by 32 percentage, 48 percentage, 50 percentage and 51 percentage, respectively. The CFAB coupled with coagulant, resulted an excessive removal of color, TSS, COD, and turbidity by 88 percentage, 92 percentage, 67 percentage and 89 percentage, respectively. (author)

  20. Packing Optimization of Sorbent Bed Containing Dissimilar and Irregular Shaped Media

    Science.gov (United States)

    Holland, Nathan; Guttromson, Jayleen; Piowaty, Hailey

    2011-01-01

    The Fire Cartridge is a packed bed air filter with two different and separate layers of media designed to provide respiratory protection from combustion products after a fire event on the International Space Station (ISS). The first layer of media is a carbon monoxide catalyst and the second layer of media is universal carbon. During development of Fire Cartridge prototypes, the two media beds were noticed to have shifted inside the cartridge. The movement of media within the cartridge can cause mixing of the bed layers, air voids, and channeling, which could cause preferential air flow and allow contaminants to pass through without removal. An optimally packed bed mitigates these risks and ensures effective removal of contaminants from the air. In order to optimally pack each layer, vertical, horizontal, and orbital agitations were investigated and a packed bulk density was calculated for each method. Packed bulk density must be calculated for each media type to accommodate variations in particle size, shape, and density. Additionally, the optimal vibration parameters must be re-evaluated for each batch of media due to variations in particle size distribution between batches. For this application it was determined that orbital vibrations achieve an optimal pack density and the two media layers can be packed by the same method. Another finding was media with a larger size distribution of particles achieve an optimal bed pack easier than media with a smaller size distribution of particles.

  1. Waste Water Treatment-Bed of Coal Fly Ash for Dyes and Pigments Industry

    Directory of Open Access Journals (Sweden)

    Syed Farman Ali Shah

    2015-12-01

    Full Text Available The highly porous power plant waste ashes have been utilized to treat toxic effluent of a dyes manufacturing plant. An attempt has been made for the first time in Pakistan, to generate an effective and economically sound treatment facility for the toxic effluent of a dyes manufacturing plant. This is an indigenous bed which could replace expensive treatment facilities, such as reverse osmosis (RO, granulated activated carbon (GAC bed, etc. The treatment efficiency was improved by coupling coagulants with fly ash adsorbent bed. The ash was collected from coal fired boilers of power plant at Lakhra Power Generation Company, Jamshoro, Pakistan. The use of this ash resolved the disposal and environmental issues by treating wastewater of chemical, dyes and pigment industry. The treatment bed comprised of briquettes of coal fly ash coupled with commercial coagulant ferrous sulfate-lime reduced COD, color, turbidity and TSS of effluent remarkably. An adsorption capacity and chemical behavior of fly ash bed was also studied. In coagulation treatment, coagulant FeSO4-lime influenced reduction of COD, color, turbidity and TSS by 32%, 48%, 50% and 51%, respectively. The CFAB coupled with coagulant, resulted an excessive removal of color, TSS, COD, and turbidity by 88%, 92%, 67% and89%, respectively.

  2. Biological and physical contributions to the accumulation of strombid gastropods in a Pliocene shell bed

    Energy Technology Data Exchange (ETDEWEB)

    Geary, D.H. (Univ. of Wisconsin, Madison (USA)); Allmon, W.D. (Univ. of South Florida, Tampa (USA))

    1990-06-01

    Before the evolutionary and ecological information contained in shell beds can be interpreted, the conditions of shell bed formation must be understood. Here the authors investigate the mode and time scale of accumulation of a dense layer of Strombus floridanus in the Pliocene Pinecrest Beds of Florida. They utilize a variety of comparative taphonomic data, including the extent of encrustation and boring on strombid shells of different ontogenetic ages, and on accompanying pelecypods of different ecological types. The taphonomic comparisons enable them to reconstruct more accurately the events of shell bed formation. The formation of the strombid shell layer involved both biological and physical components. The characteristically gregarious behavior of Strombus is reflected in the large number of individuals preserved in this layer. Based on average densities of individuals in strombid colonies today, the authors estimate that a time period of tens to hundreds of years was required to accumulate these fossils. Repeated sediment winnowing by storms, followed by rapid reburial in a regime of at least episodically high sedimentation rates, is the most likely mechanism of accumulation, and accounts for the observed patterns of encrustation and boring on the shells of Strombus and various associated pelecypods. The origin of Florida's Plio-Pleistocene shelly sands is poorly understood; analysis of this bed may provide a working model for future taphonomic studies.

  3. Linking Radial Species Segregation and Bubbling Patterns in Gas-Fluidized Beds.

    Science.gov (United States)

    Joseph, Gustavo; Hrenya, Christine; Kozlowski, Joe

    2007-11-01

    Binary mixtures of gas-fluidized Geldart Group B particles with size and/or density differences were experimentally investigated at gas velocities up to 3 times the complete fluidization velocities (ufc) of the mixtures. Steady state operation of the bed was ensured prior to data collection. Local bubbling information (mean bubble size, bubble rise velocity, and bubbling frequency) was obtained throughout the bed by means of a backscattered-light optical probe. Segregation data were obtained via bed ``freezing'' and subsequent sieving of layers. Monodisperse runs were also performed as benchmarks for the binary-mixture runs. Perceptible radial variations in species composition were encountered, with the less massive particles tending toward the bed center in most cases. For systems where the species differed in both size and density, the bottom layer presents a reversal of radial segregation pattern at gas velocities below 2ufc. At velocities below 2ufc, bubbling is seen predominantly at the bed periphery, with qualitative differences between monodisperse and mixed systems above 2ufc. A detailed analysis of the bubbling patterns at the various compositions and gas velocities is presented, and links to the observed segregation behavior are made.

  4. Drying Beds. Sludge Treatment and Disposal Course #166. Instructor's Guide [and] Student Workbook.

    Science.gov (United States)

    Klopping, Paul H.

    Provided in this lesson is introductory material on sand and surfaced sludge drying beds. Typical construction and operation, proper maintenance, and safety procedures are considered. The lesson includes an instructor's guide and student workbook. The instructor's guide contains a description of the lesson, estimated presentation time,…

  5. Identification and Characterization of Trichoderma Species Damaging Shiitake Mushroom Bed-Logs Infested by Camptomyia Pest.

    Science.gov (United States)

    Kim, Jun Young; Kwon, Hyuk Woo; Yun, Yeo Hong; Kim, Seong Hwan

    2016-05-28

    The shiitake mushroom industry has suffered from Camptomyia (gall midges) pest, which feeds on the mycelium of shiitake mushroom during its cultivation. It has been postulated that fungal damage of shiitake bed-logs is associated with infestation by the insect pest, but this is not well understood. To understand the fungal damage associated with Camptomyia pest, various Trichoderma species were isolated, identified, and characterized. In addition to two previously known Trichoderma species, T. citrinoviride and T. deliquescens, two other Trichoderma species, T. harzianum and T. atroviride, were newly identified from the pestinfested bed-log samples obtained at three mushroom farms in Cheonan, Korea. Among these four species, T. harzianum was the most evident. The results of a chromogenic media-based assay for extracellular enzymes showed that these four species have the ability to produce amylase, carboxyl-methyl cellulase, avicelase, pectinase, and β-glucosidase, thus indicating that they can degrade wood components. A dual culture assay on PDA indicated that T. harzianum, T. atroviride, and T. citrinoviride were antagonistic against the mycelial growth of a shiitake strain (Lentinula edodes). Inoculation tests on shiitake bed-logs revealed that all four species were able to damage the wood of bed-logs. Our results provide evidence that the four green mold species are the causal agents involved in fungal damage of shiitake bed-logs infested by Camptomyia pest. PMID:26930351

  6. The influence of carmustine wafer implantation on tumor bed cysts and peritumoral brain edema.

    Science.gov (United States)

    Hasegawa, Yuzo; Iuchi, Toshihiko; Sakaida, Tsukasa; Yokoi, Sana; Kawasaki, Koichiro

    2016-09-01

    The development of perifocal edema and tumor bed cyst has been reported after implantation of biodegradable carmustine wafers for the treatment of malignant gliomas. We retrospectively evaluated these changes in a series of patients; 19 consecutive patients with malignant glioma who received carmustine wafer implantation at our hospital from January 2013 through July 2013, and 28 patients who underwent surgery prior to our institution's initiation of carmustine wafer implantation, as historical controls. The volume of the tumor bed cyst and perifocal edema was calculated on MRI acquired at four time points: ⩽72hours after surgery for baseline, and at 1-4, 5-8, and 9-12weeks after surgery. The volume of the tumor bed cyst in the wafer group increased significantly relative to the control group at all time points (p=0.04). Opening of the ventricle was inversely correlated with enlargement of the tumor bed cyst in the wafer group (p=0.04). The change in the volume of perifocal edema in the wafer group was not significantly different (p=0.48), but exhibited a considerable increase in patients with anaplastic oligodendroglioma relative to glioblastoma patients in the wafer group (p=0.01). We demonstrated significant enlargement of the tumor bed cyst volume after carmustine wafer implantation, as well as the development of marked perifocal edema in patients with anaplastic oligodendroglioma. PMID:27430412

  7. Interactions among Carbon Dioxide, Heat, and Chemical Lures in Attracting the Bed Bug, Cimex lectularius L. (Hemiptera: Cimicidae

    Directory of Open Access Journals (Sweden)

    Narinderpal Singh

    2012-01-01

    Full Text Available Commercial bed bug (Cimex lectularius L. monitors incorporating carbon dioxide (CO2, heat, and chemical lures are being used for detecting bed bugs; however, there are few reported studies on the effectiveness of chemical lures in bed bug monitors and the interactions among chemical lure, CO2, and heat. We screened 12 chemicals for their attraction to bed bugs and evaluated interactions among chemical lures, CO2, and heat. The chemical lure mixture consisting of nonanal, 1-octen-3-ol, spearmint oil, and coriander Egyptian oil was found to be most attractive to bed bugs and significantly increased the trap catches in laboratory bioassays. Adding this chemical lure mixture when CO2 was present increased the trap catches compared with traps baited with CO2 alone, whereas adding heat did not significantly increase trap catches when CO2 was present. Results suggest a combination of chemical lure and CO2 is essential for designing effective bed bug monitors.

  8. Methane production from horse manure and stall waste with softwood bedding.

    Science.gov (United States)

    Wartell, Brian A; Krumins, Valdis; Alt, Jeffrey; Kang, Kathleen; Schwab, Bryan J; Fennell, Donna E

    2012-05-01

    Substantial stall waste is generated from horses on softwood bedding. The methane potential (G(pot)) of horse manure and constructed mixtures of stall waste with softwood bedding was determined at 35°C. G(pot) of 68, 191 and 273 mL/g volatile solids (VS) were estimated for three separate batches of horse manure, indicating variability in the material. Cumulative energy production over 20-40 days ranged from 3.11 ± 0.92 to 8.45 ± 5.42 × 10(5)kJ/metric ton wet weight horse manure alone, and from 1.69 ± 0.39 to 3.91 ± 0.47 × 10(5)kJ/metric ton wet weight horse manure plus softwood stall bedding (mixed at a 1:1 ratio on a VS basis). Softwood bedding was barely degradable and diluted the energy production of the stall waste; however, it did not cause inhibition of methane production from manure. Manually separated used softwood bedding contained substantial methane potential.

  9. Climate Science for a Sustainable Energy Future Test Bed and Data Infrastructure Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Dean N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Foster, I. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Van Dam, Kerstin Kleese [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Shipman, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-05-04

    The collaborative Climate Science for a Sustainable Energy Future (CSSEF) project started in July 2011 with the goal of accelerating the development of climate model components (i.e., atmosphere, ocean and sea ice, and land surface) and enhancing their predictive capabilities while incorporating uncertainty quantification (UQ). This effort required accessing and converting observational data sets into specialized model testing and verification data sets and building a model development test bed, where model components and sub-models can be rapidly evaluated. CSSEF’s prototype test bed demonstrated, how an integrated testbed could eliminate tedious activities associated with model development and evaluation, by providing the capability to constantly compare model output—where scientists store, acquire, reformat, regrid, and analyze data sets one-by-one—to observational measurements in a controlled test bed.

  10. Persistence and variability of ice-stream grounding lines on retrograde bed slopes

    Science.gov (United States)

    Robel, Alexander A.; Schoof, Christian; Tziperman, Eli

    2016-08-01

    In many ice streams, basal resistance varies in space and time due to the dynamically evolving properties of subglacial till. These variations can cause internally generated oscillations in ice-stream flow. However, the potential for such variations in basal properties is not considered by conventional theories of grounding-line stability on retrograde bed slopes, which assume that bed properties are static in time. Using a flow-line model, we show how internally generated, transient variations in ice-stream state interact with retrograde bed slopes. In contrast to predictions from the theory of the marine ice-sheet instability, our simulated grounding line is able to persist and reverse direction of migration on a retrograde bed when undergoing oscillations in the grounding-line position. In turn, the presence of a retrograde bed may also suppress or reduce the amplitude of internal oscillations in ice-stream state. We explore the physical mechanisms responsible for these behaviors and discuss the implications for observed grounding-line migration in West Antarctica.

  11. Reynolds averaged theory of turbulent shear flows over undulating beds and formation of sand waves.

    Science.gov (United States)

    Bose, Sujit K; Dey, Subhasish

    2009-09-01

    Based on the Reynolds averaged Navier-Stokes (RANS) equations and the time-averaged continuity equation, a theory of turbulent shear flow over an undulating sand bed is developed addressing the instability criterion of plane sand beds in free-surface flows leading to the formation of sand waves. In the analysis, the integration of RANS equations leads to generalized Saint Venant equations, in which the time-averaged streamwise velocity is characterized by a power law obtained from turbulence closure, treating the curvilinear streamlines by the Boussinesq approximation. As a consequence, the modified pressure distribution has a departure from the traditionally linear hydrostatic pressure distribution. The instability analysis of a plane sand bed yields the curves of the Froude number versus nondimensional wave number, determining an instability zone for which at lower Froude numbers (less than 0.8), the plane bed becomes unstable with the formation of dunes; whereas at higher Froude numbers, the plane bed becomes unstable with the formation of standing waves and antidunes. For higher Froude numbers, the experimental data for antidunes lie within the unstable zone; while for lower Froude numbers, the same is found for dunes with some experimental scatter. PMID:19905209

  12. The Suitability of the Fuel Mixture of Horse Manure and Bedding Materials for Combustion

    Science.gov (United States)

    Tyni, Sanna K.; Tiainen, Minna S.; Laitinen, Risto S.

    The mixture of horse manure and bedding materials (peat and sawdust) appear to be a potential biofuel. The chemical compositions of horse manure, bedding materials, and the mixture of these have been characterized by SEM-EDS and ICP-OES. In addition, the compositional distribution of ash of these materials has been determined and this facilitates the estimation of their propensity for ash-related problems in boilers. NOx and SOx emissions from the co-combustion are also discussed on the basis of the chemical composition of fuel mixtures. It seems that co-combustion of horse manure and bedding materials in FB boilers is suitable for small-scale energy production.

  13. Numerical Simulation and Experimental Study of Deep Bed Corn Drying Based on Water Potential

    Directory of Open Access Journals (Sweden)

    Zhe Liu

    2015-01-01

    Full Text Available The concept and the model of water potential, which were widely used in agricultural field, have been proved to be beneficial in the application of vacuum drying model and have provided a new way to explore the grain drying model since being introduced to grain drying and storage fields. Aiming to overcome the shortcomings of traditional deep bed drying model, for instance, the application range of this method is narrow and such method does not apply to systems of which pressure would be an influential factor such as vacuum drying system in a way combining with water potential drying model. This study established a numerical simulation system of deep bed corn drying process which has been proved to be effective according to the results of numerical simulation and corresponding experimental investigation and has revealed that desorption and adsorption coexist in deep bed drying.

  14. Sorting out sand and gravel : sediment transport and deposition in sand-gravel bed rivers

    NARCIS (Netherlands)

    Kleinhans, M.G.

    2002-01-01

    The general aim of this PhD-project was to gain better understanding of the sediment transport and depositional processes of sand-gravel mixtures in rivers with subaqueous dunes. The understanding of the fundamental processes of sediment transport and deposition in channel beds is crucial for morpho

  15. Ammonia, total reduced sulfides, and greenhouse gases of pine chip and corn stover bedding packs

    Science.gov (United States)

    Bedding materials may affect air quality in livestock facilities. The objective of this study was to compare headspace concentrations of ammonia (NH3), total reduced sulfides (TRS), carbon dioxide (CO2),methane (CH4), and nitrous oxide (N2O) when pine wood chips and corn stover were mixed in various...

  16. Characteristics of Sawdust and Cocopeat Beddings, and Their Usefulness According to the Fan and Pen Location for Rearing Hanwoo Cattle.

    Science.gov (United States)

    Ahn, Gyu Chul; Jang, Sun Sik; Lee, Kang Yeon; Kwak, Wan Sup; Oh, Young Kyun; Park, Keun Kyu

    2016-03-01

    This study was designed to examine the characteristics of sawdust and cocopeat bedding materials, including physicochemical properties (Exp. I) and on-farm trial (Exp. II). In Exp. I, the proportion of particle size was in the order of sawdust> cocopeat India>cocopeat Vietnam (pparticles (250 μm+below 250 μm) than sawdust, causing a dust production problem. Bulk density was cocopeat India>cocopeat Vietnam>sawdust (ptreatments showed 4.4 times higher bedding cost than sawdust. The water absorption rates were 702.0% in cocopeat India, 678.3% in cocopeat Vietnam, and 444.0% in sawdust, showing cocopeat had approximately 1.5 times higher water absorption rate than sawdust. Moisture evaporation rates after 12 h of air blowing (2.00 m/s) were higher (ptreatments, and feed bunk side (FB) and water supply side (WS) within a pen (4.5 m, width×9.0 m, length). Beddings were replaced with fresh bedding materials when moisture concentrations were over 65%. No interactions among treatments were detected for moisture concentration and increment rates, and ammonia concentrations, but a significant effect was observed (ptreatments. Both concentrations and increment rate of moisture were higher (pconcentrations and increment rate within a pen were also higher (pconcentrations and pH of beddings were not significantly different among treatments. Therefore, using cocopeat bedding with a blowing fan can extend twice the bedding utilization period, and WS within a pen showed twice the bedding-life compared to FB. Despite the outstanding characteristics of cocopeat compared with sawdust, using cocopeat as an alternative for sawdust bedding is not recommended for cattle management, considering it has 4.4 times higher bedding cost and a dust production problem.

  17. Bed rest for preventing complications after transfemoral cardiac catheterisation: a protocol of systematic review and network meta-analysis

    OpenAIRE

    Dal Molin, Alberto; Faggiano, Fabrizio; Bertoncini, Fabio; Buratti, Giulia; Busca, Erica; Casarotto, Roberta; Gaboardi, Samanta; Allara, Elias

    2015-01-01

    Background Transfemoral cardiac catheterisation is an invasive medical procedure used for therapeutic or diagnostic purposes. Postoperative bed rest can prevent a number of complications such as bleeding and haematoma formation and can result in side effects such as back pain and urinary discomfort. Currently, there is no consensus regarding the optimal length of bed rest. Our objective is to assess the effects of post-catheterisation length of bed rest on bleeding and haematoma, other vascul...

  18. Underwater microscope for measuring spatial and temporal changes in bed-sediment grain size

    Science.gov (United States)

    Rubin, David M.; Chezar, Henry; Harney, Jodi N.; Topping, David J.; Melis, Theodore S.; Sherwood, Christopher R.

    2007-01-01

    For more than a century, studies of sedimentology and sediment transport have measured bed-sediment grain size by collecting samples and transporting them back to the laboratory for grain-size analysis. This process is slow and expensive. Moreover, most sampling systems are not selective enough to sample only the surficial grains that interact with the flow; samples typically include sediment from at least a few centimeters beneath the bed surface. New hardware and software are available for in situ measurement of grain size. The new technology permits rapid measurement of surficial bed sediment. Here we describe several systems we have deployed by boat, by hand, and by tripod in rivers, oceans, and on beaches.

  19. Thermal Fatigue and Creep Assessment for the ITER Tritium SDS bed

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Woo-seok; Park, Chang-kyu; Ju, Young-sun [KAERI, Daejeon (Korea, Republic of); Kang, Hyun-goo; Jang, Min-ho; Yun, Sei-hun [National Fusion Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    As the tritium is absorbed and desorbed, the primary vessel is heated to 500 .deg. C and cool down to the room temperature. During this procedure, high alternating thermal stress occurs in the primary vessel. Fatigue analysis is conducted with the information of the magnitude and the number of the calculated cyclic load. In case that the duration for which the bed stay in high temperature increases, thermal creep effects should be evaluated. This paper describes the thermal fatigue and creep assessment for the SDS bed. For the ITER tritium SDS bed, thermal fatigue and creep assessments were performed. A new operation procedure to obtain more integrity margin was recommended. On the contrary, the other operation procedure should be considered which makes the rapid heating and cooling operation possible at the cost of giving up the marginal integrity.

  20. Interactions between SO2 and NOx emissions in fluidised bed combustion of coal. Doctoral thesis

    Energy Technology Data Exchange (ETDEWEB)

    Lin, W.

    1994-01-01

    ;Contents: Introduction; The emissions of SO2 and NOx and their interactions in fluidized-bed combustion (FBC) of coal; SO2 and NOx emissions in FBC of coal: a literature survey; Oxidation of NH3 in a fixed bed; Oxidation of NH3: influence of SO2, CO and CO2; Modeling SO2 and NOx emissions in AFBC: a simple approach; Modeling SO2 and NOx emissions in CFBC; Modeling SO2 and NOx emissions in FBC: a fundamental approach; Optimization and Conclusions.

  1. MODELING MOISTURE DIFFUSIVITY AND ENERGY CONSUMPTION OF CANTALOUPE SEEDS IN FIXED AND FLUIDIZED BED CONDITIONS

    Directory of Open Access Journals (Sweden)

    Reza Amiri Chayjan

    2012-12-01

    Full Text Available   Background.The main goal in cantaloupe seed drying is the reduction of its moisture content to a safe level, allowing storage in a long period of time. Fluidized bed dryer is a drying process with better heat and mass transfer and shorter drying time. This method is a gentle and uniform drying procedure. Fluidized bed is suitable for sensitive and high moisture materials. Drying parameters of moisture diffusivity and energy are vitally important in modelling and optimizing of the seed dryer system. Material and methods. This study investigated thin layer characteristics of cantaloupe seeds under fixed, semi fluidized and fluidized bed drying with initial moisture content about 61.99% (d.b.. A laboratory fluid- ized bed dryer was utilized in this research. Air temperature levels of 45, 55, 65 and 75°C were applied in drying experiments. Effective moisture diffusivity (Deff of cantaloupe seeds was computed by Fick’s second law in diffusion. Activation energy and specific energy consumption of cantaloupe seeds under different drying conditions were calculated. Results.Calculated values of Deff for drying experiments were in the range of 2.23·10-10and 8.61·10-10m2/s. Values of Deff increased as the input air temperature increased. Activation energy values were computed be- tween 39.21 and 37.55 kJ/mol for 45°C to 75°C, respectively. Specific energy consumption for cantaloupe seeds was calculated at the boundary of 1.58·105and 6.18·105kJ/kg. Conclusion.Results indicated that applying the fluidized bed condition is more effective for convective drying of cantaloupe seeds. Increasing air velocity tends to decrease in activation energy. Decreasing in drying air temperature in different bed conditions caused increase in the energy value. The aforesaid drying parameters are necessary to optimize the operational condition of fluidized bed dryer and to perfect design of the system.  

  2. Irregular Wave Forces on Monopile Foundations. Effect af Full Nonlinearity and Bed Slope

    DEFF Research Database (Denmark)

    Schløer, Signe; Bredmose, Henrik; Bingham, Harry B.

    2011-01-01

    Forces on a monopile from a nonlinear irregular unidirectional wave model are investigated. Two seabed profiles of different slopes are considered. Morison’s equation is used to investigate the forcing from fully nonlinear irregular waves and to compare the results with those obtained from linear...... wave theory and with stream function wave theory. The latter of these theories is only valid on a flat bed. The three predictions of wave forces are compared and the influence of the bed slope is investigated. Force-profiles of two selected waves from the irregular wave train are further compared...... with the corresponding forceprofiles from stream function theory. The results suggest that the nonlinear irregular waves give rise to larger extreme wave forces than those predicted by linear theory and that a steeper bed slope increases the wave forces both for linear and nonlinear waves. It is further found...

  3. Seasonal Greenland Ice Sheet ice flow variations in regions of differing bed and surface topography

    Science.gov (United States)

    Sole, A. J.; Livingstone, S. J.; Rippin, D. M.; Hill, J.; McMillan, M.; Quincey, D. J.

    2015-12-01

    The contribution of the Greenland Ice Sheet (GrIS) to future sea-level rise is uncertain. Observations reveal the important role of basal water in controlling ice-flow to the ice sheet margin. In Greenland, drainage of large volumes of surface meltwater to the ice sheet bed through moulins and hydrofracture beneath surface lakes dominates the subglacial hydrological system and provides an efficient means of moving mass and heat through the ice sheet. Ice surface and bed topography influence where meltwater can access the bed, and the nature of its subsequent flow beneath the ice. However, no systematic investigation into the influence of topographic variability on Greenland hydrology and dynamics exists. Thus, physical processes controlling storage and drainage of surface and basal meltwater, and the way these affect ice flow are not comprehensively understood. This presents a critical obstacle in efforts to predict the future evolution of the GrIS. Here we present high-resolution satellite mapping of the ice-surface drainage network (e.g. lakes, channels and moulins) and measurements of seasonal variations in ice flow in south west Greenland. The region is comprised of three distinct subglacial terrains which vary in terms of the amplitude and wavelength and thus the degree to which basal topography is reflected in the ice sheet surface. We find that the distribution of surface hydrological features is related to the transfer of bed topography to the ice sheet surface. For example, in areas of thinner ice and high bed relief, moulins occur more frequently and are more uniformly dispersed, indicating a more distributed influx of surface-derived meltwater to the ice sheet bed. We investigate the implications of such spatial variations in surface hydrology on seasonal ice flow rates.

  4. Design report on SCDAP/RELAP5 model improvements - debris bed and molten pool behavior

    Energy Technology Data Exchange (ETDEWEB)

    Allison, C.M.; Rempe, J.L.; Chavez, S.A.

    1994-11-01

    the SCDAP/RELAP5/MOD3 computer code is designed to describe the overall reactor coolant system thermal-hydraulic response, core damage progression, and in combination with VICTORIA, fission product release and transport during severe accidents. Improvements for existing debris bed and molten pool models in the SCDAP/RELAP5/MOD3.1 code are described in this report. Model improvements to address (a) debris bed formation, heating, and melting; (b) molten pool formation and growth; and (c) molten pool crust failure are discussed. Relevant data, existing models, proposed modeling changes, and the anticipated impact of the changes are discussed. Recommendations for the assessment of improved models are provided.

  5. High Levels Of Bed Occupancy Associated With Increased Inpatient And Thirty-Day Hospital Mortality In Denmark

    DEFF Research Database (Denmark)

    Madsen, Flemming; Ladelund, Steen; Linneberg, Allan

    2014-01-01

    High bed occupancy rates have been considered a matter of reduced patient comfort and privacy and an indicator of high productivity for hospitals. Hospitals with bed occupancy rates of above 85 percent are generally considered to have bed shortages. Little attention has been paid to the impact...... of these shortages on patients' outcomes. We analyzed all 2.65 million admissions to Danish hospitals' departments of medicine in the period 1995-2012. We found that high bed occupancy rates were associated with a significant 9 percent increase in rates of in-hospital mortality and thirty-day mortality, compared...... to low bed occupancy rates. Being admitted to a hospital outside of normal working hours or on a weekend or holiday was also significantly associated with increased mortality. The health risks of bed shortages, including mortality, could be better documented as a priority health issue. Resources should...

  6. An overview of the issues: physiological effects of bed rest and restricted physical activity

    Science.gov (United States)

    Convertino, V. A.; Bloomfield, S. A.; Greenleaf, J. E.

    1997-01-01

    Reduction of exercise capacity with confinement to bed rest is well recognized. Underlying physiological mechanisms include dramatic reductions in maximal stroke volume, cardiac output, and oxygen uptake. However, bed rest by itself does not appear to contribute to cardiac dysfunction. Increased muscle fatigue is associated with reduced muscle blood flow, red cell volume, capillarization and oxidative enzymes. Loss of muscle mass and bone density may be reflected by reduced muscle strength and higher risk for injury to bones and joints. The resultant deconditioning caused by bed rest can be independent of the primary disease and physically debilitating in patients who attempt to reambulate to normal active living and working. A challenge to clinicians and health care specialists has been the identification of appropriate and effective methods to restore physical capacity of patients during or after restricted physical activity associated with prolonged bed rest. The examination of physiological responses to bed rest deconditioning and exercise training in healthy subjects has provided significant information to develop effective rehabilitation treatments. The successful application of acute exercise to enhance orthostatic stability, daily endurance exercise to maintain aerobic capacity, or specific resistance exercises to maintain musculoskeletal integrity rather than the use of surgical, pharmacological, and other medical treatments for clinical conditions has been enhanced by investigation and understanding of underlying mechanisms that distinguish physical deconditioning from the disease. This symposium presents an overview of cardiovascular and musculoskeletal deconditioning associated with reduced physical work capacity following prolonged bed rest and exercise training regimens that have proven successful in ameliorating or reversing these adverse effects.

  7. Palynologic and petrographic variation in the Otter Creek coal beds (Stephanian, Upper Carboniferous), Western Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    Helfrich, C.T.; Hower, J.C. (Eastern Kentucky University, Richmond (USA))

    1989-08-30

    The palynology and petrology of the Lisman (Lower Otter Creek) and Upper Otter Creek coals of the Stephanian portion of the Sturgis Formation of the Western Kentucky coal field was investigated in samples from mine and roadcut exposures. The Lisman coal bed exhibits an upward decrease in palynologic diversity and an upward increase in inertinite macerals. These factors suggest a change in swamp paleoecology in response to a climate which was gradually becoming drier. The Upper Creek coal bed exhibits less lateral continuity in palynomorph assemblages than does the Lisman. The Upper Otter Creek palynomorph assemblages are less diverse than the Lisman assemblages. Overall, the variation in the Upper Otter Creek coal bed cannot be attributed with certainty to any factor other than the local relief within the swamp. 17 refs., 4 figs., 3 tabs.

  8. Bedmap2: improved ice bed, surface and thickness datasets for Antarctica

    DEFF Research Database (Denmark)

    Fretwell, P.; Pritchard, H. D.; Vaughan, D;

    2013-01-01

    the original Bedmap compilation (Bedmap1) in 2001. In particular, the Bedmap2 ice thickness grid is made from 25 million measurements, over two orders of magnitude more than were used in Bedmap1. In most parts of Antarctica the subglacial landscape is visible in much greater detail than was previously......We present Bedmap2, a new suite of gridded products describing surface elevation, ice-thickness and the seafloor and subglacial bed elevation of the Antarctic south of 60° S. We derived these products using data from a variety of sources, including many substantial surveys completed since...... million km3) and its potential contribution to sea-level rise (58 m) are similar to those of Bedmap1, but the mean thickness of the ice sheet is 4.6 % greater, the mean depth of the bed beneath the grounded ice sheet is 72 m lower and the area of ice sheet grounded on bed below sea level...

  9. Difficulties in access and estimates of public beds in intensive care units in the state of Rio de Janeiro

    Science.gov (United States)

    Goldwasser, Rosane Sonia; Lobo, Maria Stella de Castro; de Arruda, Edilson Fernandes; Angelo, Simone Aldrey; Silva, José Roberto Lapa e; de Salles, André Assis; David, Cid Marcos

    2016-01-01

    ABSTRACT OBJECTIVE To estimate the required number of public beds for adults in intensive care units in the state of Rio de Janeiro to meet the existing demand and compare results with recommendations by the Brazilian Ministry of Health. METHODS The study uses a hybrid model combining time series and queuing theory to predict the demand and estimate the number of required beds. Four patient flow scenarios were considered according to bed requests, percentage of abandonments and average length of stay in intensive care unit beds. The results were plotted against Ministry of Health parameters. Data were obtained from the State Regulation Center from 2010 to 2011. RESULTS There were 33,101 medical requests for 268 regulated intensive care unit beds in Rio de Janeiro. With an average length of stay in regulated ICUs of 11.3 days, there would be a need for 595 active beds to ensure system stability and 628 beds to ensure a maximum waiting time of six hours. Deducting current abandonment rates due to clinical improvement (25.8%), these figures fall to 441 and 417. With an average length of stay of 6.5 days, the number of required beds would be 342 and 366, respectively; deducting abandonment rates, 254 and 275. The Brazilian Ministry of Health establishes a parameter of 118 to 353 beds. Although the number of regulated beds is within the recommended range, an increase in beds of 122.0% is required to guarantee system stability and of 134.0% for a maximum waiting time of six hours. CONCLUSIONS Adequate bed estimation must consider reasons for limited timely access and patient flow management in a scenario that associates prioritization of requests with the lowest average length of stay. PMID:27191155

  10. Evaluation and Clustering Maps of Groundwater Wells in the Red Beds of Chengdu, Sichuan, China

    OpenAIRE

    Haijing Zhang; Qingyun Du; Min Yao; Fu Ren

    2016-01-01

    Since the start of the 21st century, groundwater wells have been placed in red beds to solve the problem of scarce water resources in Southwest China and have rapidly expanded to other areas. By providing examples of cartography in Chengdu and Sichuan, China, and using the locations of groundwater in fractures and pores when monitoring and managing red sandstone and mudstone wells, a series of maps of groundwater wells at different scales in the red beds of Chengdu was obtained. Most of the w...

  11. Processes and parameters involved in modeling radionuclide transport from bedded salt repositories. Final report. Technical memorandum

    International Nuclear Information System (INIS)

    The parameters necessary to model radionuclide transport in salt beds are identified and described. A proposed plan for disposal of the radioactive wastes generated by nuclear power plants is to store waste canisters in repository sites contained in stable salt formations approximately 600 meters below the ground surface. Among the principal radioactive wastes contained in these canisters will be radioactive isotopes of neptunium, americium, uranium, and plutonium along with many highly radioactive fission products. A concern with this form of waste disposal is the possibility of ground-water flow occurring in the salt beds and endangering water supplies and the public health. Specifically, the research investigated the processes involved in the movement of radioactive wastes from the repository site by groundwater flow. Since the radioactive waste canisters also generate heat, temperature is an important factor. Among the processes affecting movement of radioactive wastes from a repository site in a salt bed are thermal conduction, groundwater movement, ion exchange, radioactive decay, dissolution and precipitation of salt, dispersion and diffusion, adsorption, and thermomigration. In addition, structural changes in the salt beds as a result of temperature changes are important. Based upon the half-lives of the radioactive wastes, he period of concern is on the order of a million years. As a result, major geologic phenomena that could affect both the salt bed and groundwater flow in the salt beds was considered. These phenomena include items such as volcanism, faulting, erosion, glaciation, and the impact of meteorites. CDM reviewed all of the critical processes involved in regional groundwater movement of radioactive wastes and identified and described the parameters that must be included to mathematically model their behavior. In addition, CDM briefly reviewed available echniques to measure these parameters

  12. Processes and parameters involved in modeling radionuclide transport from bedded salt repositories. Final report. Technical memorandum

    Energy Technology Data Exchange (ETDEWEB)

    Evenson, D.E.; Prickett, T.A.; Showalter, P.A.

    1979-07-01

    The parameters necessary to model radionuclide transport in salt beds are identified and described. A proposed plan for disposal of the radioactive wastes generated by nuclear power plants is to store waste canisters in repository sites contained in stable salt formations approximately 600 meters below the ground surface. Among the principal radioactive wastes contained in these canisters will be radioactive isotopes of neptunium, americium, uranium, and plutonium along with many highly radioactive fission products. A concern with this form of waste disposal is the possibility of ground-water flow occurring in the salt beds and endangering water supplies and the public health. Specifically, the research investigated the processes involved in the movement of radioactive wastes from the repository site by groundwater flow. Since the radioactive waste canisters also generate heat, temperature is an important factor. Among the processes affecting movement of radioactive wastes from a repository site in a salt bed are thermal conduction, groundwater movement, ion exchange, radioactive decay, dissolution and precipitation of salt, dispersion and diffusion, adsorption, and thermomigration. In addition, structural changes in the salt beds as a result of temperature changes are important. Based upon the half-lives of the radioactive wastes, he period of concern is on the order of a million years. As a result, major geologic phenomena that could affect both the salt bed and groundwater flow in the salt beds was considered. These phenomena include items such as volcanism, faulting, erosion, glaciation, and the impact of meteorites. CDM reviewed all of the critical processes involved in regional groundwater movement of radioactive wastes and identified and described the parameters that must be included to mathematically model their behavior. In addition, CDM briefly reviewed available echniques to measure these parameters.

  13. Sex of college students moderates associations among bedtime, time in bed, and circadian phase angle.

    Science.gov (United States)

    Van Reen, Eliza; Sharkey, Katherine M; Roane, Brandy M; Barker, David; Seifer, Ronald; Raffray, Tifenn; Bond, Tamara L; Carskadon, Mary A

    2013-12-01

    Sex differences in circadian rhythms have been reported with some conflicting results. The timing of sleep and length of time in bed have not been considered, however, in previous such studies. The current study has 3 major aims: (1) replicate previous studies in a large sample of young adults for sex differences in sleep patterns and dim light melatonin onset (DLMO) phase; (2) in a subsample constrained by matching across sex for bedtime and time in bed, confirm sex differences in DLMO and phase angle of DLMO to bedtime; (3) explore sex differences in the influence of sleep timing and length of time in bed on phase angle. A total of 356 first-year Brown University students (207 women) aged 17.7 to 21.4 years (mean = 18.8 years, SD = 0.4 years) were included in these analyses. Wake time was the only sleep variable that showed a sex difference. DLMO phase was earlier in women than men and phase angle wider in women than men. Shorter time in bed was associated with wider phase angle in women and men. In men, however, a 3-way interaction indicated that phase angles were influenced by both bedtime and time in bed; a complex interaction was not found for women. These analyses in a large sample of young adults on self-selected schedules confirm a sex difference in wake time, circadian phase, and the association between circadian phase and reported bedtime. A complex interaction with length of time in bed occurred for men but not women. We propose that these sex differences likely indicate fundamental differences in the biology of the sleep and circadian timing systems as well as in behavioral choices. PMID:24336420

  14. A STUDY OF EMOTIONAL INTELLIGENCE OF DEGREE AND B.ED. COLLEGE TEACHERS OF RAJASTHAN IN RELATION TO GENDER

    OpenAIRE

    Rajender Kumar

    2016-01-01

    This study aimed to find out difference in emotional intelligence of degree and B.Ed. college teachers of Rajasthan. The Emotional Intelligence Scale by Dr.Vinit Khera, Ms.Puja Ahuja and Ms.Sarabjit Kaur was used to assess the emotional intelligence of degree and B.Ed. college teachers of Rajasthan. The scale was administered on 160 degree and B.Ed. college teachers. The present study revealed that there is no significant difference in emotional intelligence of degree and B.Ed. college teachers.

  15. A STUDY OF TEACHER EFFECTIVENESS OF DEGREE AND B.ED. COLLEGE TEACHERS OF RAJASTHAN IN RELATION TO LOCALITY

    OpenAIRE

    Rajender Kumar

    2016-01-01

    This study aimed to find out difference in teacher effectiveness of degree and B.Ed. college teachers of Rajasthan. The Teacher Effectiveness Scale by Dr.Shallu Puri and Prof. S.C. Gakhar was used to assess the teacher effectiveness of degree and B.Ed. college teachers of Rajasthan. The scale was administered on 160 degree and B.Ed. college teachers. The present study revealed that there is no significant difference in teacher effectiveness of degree and B.Ed. college teachers.

  16. Comparison of the Pentax Airwayscope, Glidescope Video Laryngoscope, and Macintosh Laryngoscope During Chest Compression According to Bed Height.

    Science.gov (United States)

    Kim, Wonhee; Lee, Yoonje; Kim, Changsun; Lim, Tae Ho; Oh, Jaehoon; Kang, Hyunggoo; Lee, Sanghyun

    2016-02-01

    We aimed to investigate whether bed height affects intubation performance in the setting of cardiopulmonary resuscitation and which type of laryngoscope shows the best performance at each bed height.A randomized crossover manikin study was conducted. Twenty-one participants were enrolled, and they were randomly allocated to 2 groups: group A (n = 10) and group B (n = 11). The participants underwent emergency endotracheal intubation (ETI) using the Airwayscope (AWS), Glidescope video laryngoscope, and Macintosh laryngoscope in random order while chest compression was performed. Each ETI was conducted at 2 levels of bed height (minimum bed height: 68.9  cm and maximum bed height: 101.3 cm). The primary outcomes were the time to intubation (TTI) and the success rate of ETI. The P value for statistical significance was set at 0.05 and 0.017 in post-hoc test.The success rate of ETI was always 100% regardless of the type of laryngoscope or the bed height. TTI was not significantly different between the 2 bed heights regardless of the type of laryngoscope (all P > 0.05). The time for AWS was the shortest among the 3 laryngoscopes at both bed heights (13.7  ±  3.6 at the minimum bed height and 13.4  ±  4.7 at the maximum bed height) (all P bed height, whether adjusted to the minimum or maximum setting, did not affect intubation performance. In addition, regardless of the bed height, the intubation time with the video laryngoscopes, especially AWS, was significantly shorter than that with the direct laryngoscope during chest compression.

  17. Bed slope effects on turbulent wave boundary layers: 2. Comparison with skewness, asymmetry, and other effects

    DEFF Research Database (Denmark)

    Fuhrman, David R.; Fredsøe, Jørgen; Sumer, B. Mutlu

    2009-01-01

    contributions believed to play a prominent role in cross-shore boundary layer and sediment transport processes: (1) converging-diverging effects from bed slope, (2) wave skewness, (3) wave asymmetry, and (4) waves combined with superposed negative currents (intended to loosely represent, for example, return...... currents or undertow). The effects from each of the four components are isolated and quantified using a standard set of bed shear stress quantities, allowing their easy comparison. For conditions representing large shallow-water waves on steep slopes, the results suggest that converging-diverging effects...... from beach slope may make a significant onshore bed load contribution. Generally, however, the results suggest wave skewness (in addition to conventional steady streaming) as the most important onshore contribution outside the surf zone. Streaming induced within the wave boundary layer is also...

  18. Radionuclide concentrations in bed sediment and fish tissue within the Rio Grande drainage basin

    Energy Technology Data Exchange (ETDEWEB)

    Booher, J.L.; Fresquez, P.R.; Carter, L.F.; Gallaher, B.M.; Mullen, M.A.

    1998-02-01

    In 1992-93, Los Alamos National Laboratory collaborated with the U.S. Geological Survey in an effort to characterize radionuclide concentrations in bed sediment and fish tissue within the Rio Grande drainage basin from Colorado to Texas. Bed sediment was sampled from 18 locations for cesium ({sup 137}Cs), tritium ({sup 3}H), strontium ({sup 90}Sr), plutonium ({sup 238}Pu and {sup 239}Pu), americium ({sup 241}Am), total uranium ({sup tot}U) and alpha, beta, and gamma activity. Fish tissue was sampled from 12 locations for {sup 137}Cs, {sup 90}Sr, {sup 238}Pu, {sup 239}Pu and {sup tot}U.

  19. Radionuclide concentrations in bed sediment and fish tissue within the Rio Grande drainage basin

    International Nuclear Information System (INIS)

    In 1992-93, Los Alamos National Laboratory collaborated with the U.S. Geological Survey in an effort to characterize radionuclide concentrations in bed sediment and fish tissue within the Rio Grande drainage basin from Colorado to Texas. Bed sediment was sampled from 18 locations for cesium (137Cs), tritium (3H), strontium (90Sr), plutonium (238Pu and 239Pu), americium (241Am), total uranium (totU) and alpha, beta, and gamma activity. Fish tissue was sampled from 12 locations for 137Cs, 90Sr, 238Pu, 239Pu and totU

  20. Penrose's law revisited: the relationship between mental institution beds, prison population and crime rate.

    Science.gov (United States)

    Hartvig, Pål; Kjelsberg, Ellen

    2009-01-01

    In 1939, Lionel Penrose published a cross-sectional study from 18 European countries, including the Nordic, in which he demonstrated an inverse relationship between the number of mental hospital beds and the number of prisoners. He also found strong negative correlations between the number of mental hospital beds and the number of deaths attributed to murder. He argued that by increasing the number of mental institution beds, a society could reduce serious crimes and imprisonment rates. The aim of the study was to test Penrose's theories longitudinally by monitoring the capacity of all psychiatric institutions and prisons in a society over time. From official statistics, we collected and systematized all relevant information regarding the number of mental institution beds and prisoners in Norway during the years 1930-2004, along with major crime statistics for the same period. During the years 1930-59, there was a 2% population-adjusted increase in mental institution beds and a 30% decrease in the prison population. During 1960-2004, there was a 74% population-adjusted decrease in mental institution beds and a 52% increase in the prison population. The same period saw a 500% increase in overall crime and a 900% increase in violent crimes, with a concurrent 94% increase in the size of the country's police force. Penrose's law proved remarkably robust in the longitudinal perspective. As opposed to Penrose, however, we argue that the rise in crime rates only to a very limited extent can be attributed to mental health de-institutionalization. PMID:18985517

  1. Influence of Chemical and Thermodynamic Parameters on the Flue Gas Desulphurization Efficiency in a Circulating Fluidized Bed

    Institute of Scientific and Technical Information of China (English)

    Baoguo FAN; Changfu YOU; Haiying QI; Guangming XIANG; Xuchang XU

    2001-01-01

    An experimental study has been performed systematically on flue gas desulphurization by using circulating fluidized bed. The relationship, between desulphurization efficiency and the parameters of thermodynamics and chemistry, was investigated basically. It is shown that the bed temperature and the vapor partial pressure in the bed are the important parameters that influence the desulphurization efficiency. The closer the bed temperature to the dew point and the higher the vapor partial pressure, the higher is the desulphurization efficiency. With increasing of Ca/S, the desulphurization efficiency ascends. Comparing with different operating methods, the optimum method has been found.

  2. A Three-Point Method for Separating Incident and Reflected Waves over A Sloping Bed

    Institute of Scientific and Technical Information of China (English)

    CHANG Hsien-Kuo

    2002-01-01

    This study presents a three-point method for separating incident and reflected waves to explain normally incident waves' propagating over a sloping bed. Linear wave shoaling is used to determine changes in wave amplitude and phase in response to variations of bathymetry. The wave reflection coefficient and incident amplitude are estimated from wave heights measured at three fixed wave gauges with unequal spacing. Sensitivity analysis demonstrates that the proposed method can predict the reflection and amplitude of waves over a sloping bed more accurately than the two-point method.

  3. DNA binding during expanded bed adsorption and factors affecting adsorbent aggregation

    DEFF Research Database (Denmark)

    Arpanaei, Ayyoob; Mathiasen, N.; Hobley, Timothy John

    2008-01-01

    tolerance of anion exchangers when binding DNA. However, more importantly. with the adsorbents examined here. attempts to reduce bed aggregation by feedstock conditioning with added salt may increase DNA binding leading to a reduction in expanded bed adsorption performance compromising protein capture...... ligand densities to be examined. Very high dynamic binding capacities at 10% breakthrough were found in the absence of added salt. However, the highest binding capacities (similar to 10 and similar to 19mg DNA ml(-1) gel) were found in buffers containing added salt at concentrations of either 0.25 or 0......) even though the dynamic binding capacity was reduced as DNA concentration was increased. The extent of bed contraction during DNA loading was found to be a function of added salt concentration and ligand density of the adsorbent. The results imply that ligand density significantly affects the salt...

  4. Experimental investigation of thermal conductivity coefficient and heat exchange between fluidized bed and inclined exchange surface

    Directory of Open Access Journals (Sweden)

    B. Stojanovic

    2009-06-01

    Full Text Available The paper presents experimental research of thermal conductivity coefficients of the siliceous sand bed fluidized by air and an experimental investigation of the particle size influence on the heat transfer coefficient between fluidized bed and inclined exchange surfaces. The measurements were performed for the specific fluidization velocity and sand particle diameters d p=0.3, 0.5, 0.9 mm. The industrial use of fluidized beds has been increasing rapidly in the past 20 years owing to their useful characteristics. One of the outstanding characteristics of a fluidized bed is that it tends to maintain a uniform temperature even with nonuniform heat release. On the basis of experimental research, the influence of the process's operational parameters on the obtained values of the bed's thermal conductivity has been analyzed. The results show direct dependence of thermal conductivity on the intensity of mixing, the degree of fluidization, and the size of particles. In the axial direction, the coefficients that have been treated have values a whole order higher than in the radial direction. Comparison of experimental research results with experimental results of other authors shows good agreement and the same tendency of thermal conductivity change. It is well known in the literature that the value of the heat transfer coefficient is the highest in the horizontal and the smallest in the vertical position of the heat exchange surface. Variation of heat transfer, depending on inclination angle is not examined in detail. The difference between the values of the relative heat transfer coefficient between vertical and horizontal heater position for all particle sizes reduces by approximately 15% with the increase of fluidization rate.

  5. EXTERNAL-LOOP AIRLIFT MAGNETICALLY STABILIZED BED--MINIMUM STABILIZATION AND FLUIDIZATION CONDITIONS

    Institute of Scientific and Technical Information of China (English)

    Jordan Hristov

    2005-01-01

    Experimental study of an airlift with a magnetically stabilized bed in the riser bottom has been performed.External magnetic field allows easy control of magnetized bed structure and liquid circulation rate. Minimum stabilization and fluidization conditions have been determined experimentally and by a three-line graphical method. Semi-empirical data correlations of sections of the experimental curves have been performed. Scaling relationships known from non-magnetic airlift are applicable too, but with the assumption that the magnetic field affects the loop friction coefficient only.

  6. Modeling Non-Fickian Transport and Hyperexponential Deposition for Deep Bed Filtration

    DEFF Research Database (Denmark)

    Yuan, Hao; Shapiro, Alexander

    2010-01-01

    An integral model of the deep bed filtration process has been developed. It incorporates pore and particle size distributions, as well as the particle residence time distribution in the framework of the continuous time random walk theory. Numerical modeling is carried out to study the factors...... influencing breakthrough curves and deposition profiles for the deep bed filtration systems. Results are compared with a large set of experimental observations. Our findings show that highly dispersed breakthrough curves, e.g. those with early arrivals and large ending tails, correspond to large dispersion...

  7. A Novel Atmospheric Pressure Plasma Fluidized Bed and Its Application in Mutation of Plant Seeds

    Institute of Scientific and Technical Information of China (English)

    CHEN Guang-Liang; WANG Zhen-Quan; HAN Er-Li; FU Ya-Bo; YANG Si-Ze; FAN Song-Hua; LI Chun-Ling; GU Wei-Chao; FENG Wen-Ran; ZHANG Gu-Ling; WANG Jiu-Li; Latif K.; ZHANG Shu-Gen

    2005-01-01

    @@ An atmospheric pressure plasma fluidized bed (APPFB) is designed to generate plasma using a dielectric barrier discharge (DBD) with one liquid electrode. In the APPFB system, the physical properties of DBD discharge and its application in plant-seed mutating are studied fundamentally. The results show that the generated plasma is a typical glow discharge free from filament and arc plasma, and the macro-temperature of the plasma fluidized bed is nearly at room temperature. There are no obvious changes in the pimientos when their seeds are treated by APPFB, but great changes are found for coxcombs.

  8. Mechanisms of formation and destruction of nitrogen oxides during polyamide incineration in a fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Hahnel, F.; Gadiou, R.; Prado, G. [Univ. de Haute Alsace, Mulhouse (France). Lab. de Gestion des Risques et Environnement

    1998-09-01

    In order to study the incineration of nitrogen-containing polymers, a fludized bed has been built. This paper reports the results for polyamide 6-6 incineration. The main nitrogen containing species have been identified, and the axial profiles of concentration of nitrogen oxides, HCN and NH3 have been measured. The main steps of decomposition of the polyamide were identified. We present an experimental investigation of the influence of operating parameters (temperature, excess air) on the formation and reduction of polymer combustion products. The yields of conversion of nitrogen to the different N-species have been calculated as a function of excess air in the fluidized bed. (orig.)

  9. Flow visualizing study of fluidized bed for incineration and/or coal combustion technology

    Energy Technology Data Exchange (ETDEWEB)

    Ozawa, Mamoru [Kansai Univ., Suita, Osaka (Japan). Faculty of Engineering

    1997-02-01

    A simulated fluidized-bed heat exchanger was visualized using a neutron radiography system. The void fraction distribution and its fluctuation were obtained by means of an image processing technique. On the basis of the processed image, the mechanism of a large particle movement and the flow pattern in the tube bank immersed in the bed were investigated. Observed flow pattern in the tube bank indicated an importance of the tube arrangement on the void fraction fluctuation and thus the heat transfer around tubes. (author)

  10. Complex burrows of the mud shrimp Callianassa truncata and their geochemical impact in the sea bed

    DEFF Research Database (Denmark)

    Ziebis, W.; Forster, S.; Huettel, M.;

    1996-01-01

    the overlying water and rapid consumption within the sea bed, Macrofauna organisms living within the sea bed affect the physical structure of the sea floor, its chemical zonations and the exchange processes across the sediment-water interface(3,4). Thalassinidean mud-shrimps are often abundant in tropical......). Here we report the use of a diver observatory within the seabed, along with in situ measurements, to assess the geochemical impact of the mud-shrimp Callianassa truncata Giard and Bonnier (Decapoda, Thalassinidea), a species that commonly inhabits sandy sediments in the Mediterranean sea....

  11. Hydrogeochemistry and coal-associated bacterial populations from a methanogenic coal bed

    Science.gov (United States)

    Barnhart, Elliott P.; Weeks, Edwin P.; Jones, Elizabeth J.P.; Ritter, Daniel J.; McIntosh, Jennifer C.; Clark, Arthur C.; Ruppert, Leslie F.; Cunningham, Alfred B.; Vinson, David S.; Orem, William H.; Fields, Matthew W.

    2016-01-01

    Biogenic coalbed methane (CBM), a microbially-generated source of natural gas trapped within coal beds, is an important energy resource in many countries. Specific bacterial populations and enzymes involved in coal degradation, the potential rate-limiting step of CBM formation, are relatively unknown. The U.S. Geological Survey (USGS) has established a field site, (Birney test site), in an undeveloped area of the Powder River Basin (PRB), with four wells completed in the Flowers-Goodale coal bed, one in the overlying sandstone formation, and four in overlying and underlying coal beds (Knoblach, Nance, and Terret). The nine wells were positioned to characterize the hydraulic conductivity of the Flowers-Goodale coal bed and were selectively cored to investigate the hydrogeochemistry and microbiology associated with CBM production at the Birney test site. Aquifer-test results indicated the Flowers-Goodale coal bed, in a zone from about 112 to 120 m below land surface at the test site, had very low hydraulic conductivity (0.005 m/d) compared to other PRB coal beds examined. Consistent with microbial methanogenesis, groundwater in the coal bed and overlying sandstone contain dissolved methane (46 mg/L average) with low δ13C values (−67‰ average), high alkalinity values (22 meq/kg average), relatively positive δ13C-DIC values (4‰ average), and no detectable higher chain hydrocarbons, NO3−, or SO42−. Bioassay methane production was greatest at the upper interface of the Flowers-Goodale coal bed near the overlying sandstone. Pyrotag analysis identified Aeribacillus as a dominant in situbacterial community member in the coal near the sandstone and statistical analysis indicated Actinobacteria predominated coal core samples compared to claystone or sandstone cores. These bacteria, which previously have been correlated with hydrocarbon-containing environments such as oil reservoirs, have demonstrated the ability to produce biosurfactants to break down

  12. Comparison between finite volume and lattice-Boltzmann method simulations of gas-fluidised beds: bed expansion and particle-fluid interaction force

    Science.gov (United States)

    Third, J. R.; Chen, Y.; Müller, C. R.

    2016-07-01

    Lattice-Boltzmann method (LBM) simulations of a gas-fluidised bed have been performed. In contrast to the current state-of-the-art coupled computational fluid dynamics-discrete element method (CFD-DEM) simulations, the LBM does not require a closure relationship for the particle-fluid interaction force. Instead, the particle-fluid interaction can be calculated directly from the detailed flow profile around the particles. Here a comparison is performed between CFD-DEM and LBM simulations of a small fluidised bed. Simulations are performed for two different values of the superficial gas velocity and it is found that the LBM predicts a larger bed expansion for both flowrates. Furthermore the particle-fluid interaction force obtained for LBM simulations is compared to the force which would be predicted by a CFD-DEM model under the same conditions. On average the force predicted by the CFD-DEM closure relationship is found to be significantly smaller than the force obtained from the LBM.

  13. A three-dimensional k-ε-kp model in curvilinear coordinates for sediment movement and bed evolution

    Institute of Scientific and Technical Information of China (English)

    SHEN YongMing; LIU Cheng

    2009-01-01

    To aim at the substitution of the magnitude and direction of water flow movement near bed for those of bed load transport in solid-liquid two-phase one-fluid model, and to simulate the effect of secondary flow on transverse bed load transport in channel bends and the effect of bed slope on bed load transport in a better way, a three-dimensional k-ε-kp solid-liquid two-phase two-fluid model in curvilinear coordinates is solved numerically with a finite-volume method on an adaptive grid for studying water-sediment movements and bed evolution in a 120° channel bend. Numerical results show that the trajectories of solid-phase deviate from those of liquid-phase in the channel bend, and the deviation increases with the increase of the particle diameters. The calculated bed deformation by the k-ε-kpmodel is in better agreement with measured bed deformation than those by one-fluid model. It is proved that the k-ε-kp model can simulate the effect of secondary flow on lateral bed load transport with the higher accuracy than the one-fluid model.

  14. A three-dimensional k-ε-k_p model in curvilinear coordinates for sediment movement and bed evolution

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    To aim at the substitution of the magnitude and direction of water flow movement near bed for those of bed load transport in solid-liquid two-phase one-fluid model, and to simulate the effect of secondary flow on transverse bed load transport in channel bends and the effect of bed slope on bed load trans- port in a better way, a three-dimensional k-ε-kp solid-liquid two-phase two-fluid model in curvilinear coordinates is solved numerically with a finite-volume method on an adaptive grid for studying wa- ter-sediment movements and bed evolution in a 120° channel bend. Numerical results show that the trajectories of solid-phase deviate from those of liquid-phase in the channel bend, and the deviation increases with the increase of the particle diameters. The calculated bed deformation by the k-ε-kp model is in better agreement with measured bed deformation than those by one-fluid model. It is proved that the k-ε-kp model can simulate the effect of secondary flow on lateral bed load transport with the higher accuracy than the one-fluid model.

  15. A review of dryout heat fluxes and coolability of particle beds. APRI 4, Stage 2 Report

    Energy Technology Data Exchange (ETDEWEB)

    Lindholm, Ilona [VTT Energy, Helsinki (Finland)

    2002-04-01

    Dryout heat flux experiments on particle beds have been reviewed. The observed dryout heat flux varies from some tens of kW/m{sup 2} to well over 1 MW/m 2 . The variation can be qualitatively and to some extent also quantitatively explained. The effect of particle diameter has been clearly demonstrated. For particles having diameter less than about 1 mm, the dryout heat flux on the order of 100-200 kW/m{sup 2}, and increases on square of the particle diameter. For larger than 1 mm particles the dryout heat flux increases on square root of the particle diameter. Typical values for {approx} 5 mm particles is 500 kW/m{sup 2} to 1 MW/m{sup 2} . An effect of bed thickness can be seen for small particles and medium range (50-500 mm) beds. For thick beds, > 500 mm, the dryout heat flux does not any more change as the bed height increases. The dryout heat flux increases with increasing coolant pressure. This can be explained by the increasing vapour density, which can remove more latent heat from the bed. Debris bed stratification, with small particles on top, clearly decreases the dryout heat flux. The dryout heat flux in a stratified bed can even be smaller than a heat flux of an equivalent debris bed consisting of the smaller particles alone. This is due to the capillary force, which draws liquid towards the smaller particles and causes the dryout to occur at the interface of the particle layers. A model has been developed by Lipinski to estimate dryout heat fluxes in a particle bed. The model has been derived based on solution of momentum, energy and mass conservation equations for two phases. The 1-D model can take into account variable particle sizes (stratification) along the bed and different coolant entry positions. It has been shown that the model can quite well predict the observed dryout characteristics in most experiments. The simpler 0-D model can give reasonable estimates for non-stratified beds. Results and observations of several tests on melt jet

  16. The statistical character of packed-bed heat transport properties

    OpenAIRE

    Wijngaarden, R.J.; Westerterp, K. R.

    1992-01-01

    Packed beds are essentially heterogeneous on a pellet scale. For random packed beds this heterogeneity causes a statistical character both on a pellet and bed scale. We discuss experimental results which deal with bed-scale statistics.

  17. Emissions and distribution of methyl bromide in field beds applied at two rates and covered with two types of plastic mulches.

    Science.gov (United States)

    Ou, Li-Tse; Thomas, John E; Allen, L Hartwell; Vu, Joseph C; Dickson, Donald W

    2007-01-01

    A field experiment was conducted to compare two plastic mulches and two application rates on surface emissions and subsurface distribution of methyl bromide (MBr) in field beds in Florida. Within 30 minutes after injection of MBr to 30 cm depth, MBr had diffused upward to soil surface in all beds covered with polyethylene film (PE) or virtually impermeable film (VIF) and applied at a high rate (392 kg/ha) and a low rate (196 kg/ha). Due to the highly permeable nature of PE, within 30 minutes after injection, MBr volatilized from the bed surfaces of the two PE-covered beds into the atmosphere. The amount of volatilization was greater for the high rate-treatment bed. On the other hand, volatilization of MBr from the bed surfaces of the two VIF-covered beds were negligible. Volatilization losses occurred from the edges of all the beds covered with PE or VIF and were greater from the high rate-treatment beds. Initial vertical diffusion of MBr in the subsurface of the beds covered with PE or VIF was mainly upward, as large concentrations of MBr were detected from near bed surfaces to 20 cm depth in these beds 30 minutes after injection and little or no MBr was found at 40 cm depth. The two VIF-covered beds exhibited greater MBr concentrations and longer resident times in the root zone (0.5-40 cm depth) than corresponding PE-covered beds. Concentrations of MBr in the root zone of the high rate-treatment beds were 3.6-6.1 times larger than the low rate-treatment beds during the first days after application. In conclusion, VIF promoted retention of MBr in the root zone and, if volatilization loss from bed edges can be blocked, volatilization loss from VIF-covered beds should be negligible.

  18. Condition and Extent of the Natural Oyster Beds and Barren Bottoms in the Vicinity of Apalachicola, Fla.

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A survey of oyster beds in the vicinity of Apalachicola, FL was conducted in 1915. The area of the oyster beds is 7,135 acres, or 11.1 square miles, of which...

  19. Comparison of waste water treatment between completely mixed and fluidised bed reactor; development and structure of biomass

    Energy Technology Data Exchange (ETDEWEB)

    Toman, M.; Mejac, B.

    1988-08-01

    The aerobic biological treatment of waste water from production of semisynthetic antibiotics in a completely mixed reactor and in a fluidised bed reactor was studied. The formation and development of new biomass on the sand of a fluidised bed was observed, so that differences in the structure of organisms of the concomitant biocenosis could be detected. In a fluidised bed reactor the same quality of treatednwater was gained on account of a 4-5 times higher volumetric and hydraulic loading as it was the case with a conventional activated sludge plant. The biocenosis of the fluidised bed was abundant in individua and species. The biofilm of the sand depended on substrate degradation rate as well as on rubbing among the sand particles. An optimal biofilm developed on the sand of a fluidised bed reactor 10 to 15 days after the experiment had began, and that condition remained unchanged as the experiment continued.

  20. Characteristics of Sawdust and Cocopeat Beddings, and Their Usefulness According to the Fan and Pen Location for Rearing Hanwoo Cattle.

    Science.gov (United States)

    Ahn, Gyu Chul; Jang, Sun Sik; Lee, Kang Yeon; Kwak, Wan Sup; Oh, Young Kyun; Park, Keun Kyu

    2016-03-01

    This study was designed to examine the characteristics of sawdust and cocopeat bedding materials, including physicochemical properties (Exp. I) and on-farm trial (Exp. II). In Exp. I, the proportion of particle size was in the order of sawdust> cocopeat India>cocopeat Vietnam (pcocopeat Vietnam>sawdust (pblowing (2.00 m/s) were higher (pblowing 2.00 m/s) and no fan treatments, and feed bunk side (FB) and water supply side (WS) within a pen (4.5 m, width×9.0 m, length). Beddings were replaced with fresh bedding materials when moisture concentrations were over 65%. No interactions among treatments were detected for moisture concentration and increment rates, and ammonia concentrations, but a significant effect was observed (pblowing fan can extend twice the bedding utilization period, and WS within a pen showed twice the bedding-life compared to FB. Despite the outstanding characteristics of cocopeat compared with sawdust, using cocopeat as an alternative for sawdust bedding is not recommended for cattle management, considering it has 4.4 times higher bedding cost and a dust production problem. PMID:26950878

  1. Particle fuel bed tests

    International Nuclear Information System (INIS)

    Gas-cooled reactors, using packed beds of small diameter coated fuel particles have been proposed for compact, high-power systems. The particulate fuel used in the tests was 800 microns in diameter, consisting of a thoria kernel coated with 200 microns of pyrocarbon. Typically, the bed of fuel particles was contained in a ceramic cylinder with porous metallic frits at each end. A dc voltage was applied to the metallic frits and the resulting electric current heated the bed. Heat was removed by passing coolant (helium or hydrogen) through the bed. Candidate frit materials, rhenium, nickel, zirconium carbide, and zirconium oxide were unaffected, while tungsten and tungsten-rhenium lost weight and strength. Zirconium-carbide particles were tested at 2000 K in H2 for 12 hours with no visible reaction or weight loss

  2. Enuresis (Bed-Wetting)

    Science.gov (United States)

    ... get out of bed to go to the bathroom. When do most children achieve bladder control? Children ... ask questions about your child's daytime and nighttime bathroom habits. Then your doctor will do a physical ...

  3. Optimum process design of packed bed type thermal storage systems and other applications

    Energy Technology Data Exchange (ETDEWEB)

    Bindra, Hitesh; Bueno, Pablo

    2016-10-25

    Methods and systems for optimizing the process of heat and/or mass transfer operations in packed beds and embodiments of applications of the methods are disclosed herein below. In one instance, the method results in the profile of the quantity representative of the heat and/or mass transfer operation having a propagating substantially sharp front.

  4. Study on madder pigment dyeing linen fabric by ultrasonic method%超声波法茜草色素上染亚麻织物工艺探讨

    Institute of Scientific and Technical Information of China (English)

    伍玉娟; 王晴洁; 曹红梅

    2015-01-01

    在天然染料茜草色素上染亚麻织物时,借助超声波的作用对亚麻织物进行预处理后再染色以及超声波直接染色。探索出超声波对亚麻预处理的优化工艺:改性温度40℃,改性时间20 min,频率42.5 kHz。超声波直接染色的优化工艺:染色温度30℃,染色时间20 min,频率43.5 kHz。超声波直接染色织物的表面得色量较高,颜色鲜艳,皂洗牢度好,匀染性好,耗时短。%The madder pigment of natural dye dyes linen fabrics with dyeing after pretreatment and ultrasonic directly dyeing. Optimal conditions for linen fabric pretreatment with ultrasonic was as following: modification temperature 40℃, modification time 20 min, frequency 42.5 kHz. The optimal conditions for ultrasonic direct dyeing was that of dyeing temperature 30℃, dyeing time 20 min, frequency 43.5 kHz. The color of dyed fabrics which were dyed by ultrasonic method directly is deep and fresh. The soaping fastness and level dyeing property of dyed fabrics are excellent and the time-consuming of dyeing is short.

  5. Aeolian Sand Transport in the Planetary Context: Respective Roles of Aerodynamic and Bed-Dilatancy Thresholds

    Science.gov (United States)

    Marshall, J. R.; Borucki, J.; Bratton, C.

    1999-01-01

    The traditional view of aeolian sand transport generally estimates flux from the perspective of aerodynamic forces creating the airborne grain population, although it has been recognized that "reptation" causes a significant part of the total airborne flux; reptation involves both ballistic injection of grains into the air stream by the impact of saltating grains as well as the "nudging" of surface grains into a creeping motion. Whilst aerodynamic forces may initiate sand motion, it is proposed here that within a fully-matured grain cloud, flux is actually governed by two thresholds: an aerodynamic threshold, and a bed-dilatancy threshold. It is the latter which controls the reptation population, and its significance increases proportionally with transport energy. Because we only have experience with terrestrial sand transport, extrapolations of aeolian theory to Mars and Venus have adjusted only the aerodynamic factor, taking gravitational forces and atmospheric density as the prime variables in the aerodynamic equations, but neglecting reptation. The basis for our perspective on the importance of reptation and bed dilatancy is a set of experiments that were designed to simulate sand transport across the surface of a martian dune. Using a modified sporting crossbow in which a sand-impelling sabot replaced the bolt-firing mechanism, individual grains of sand were fired at loose sand targets with glancing angles typical of saltation impact; grains were projected at about 80 m/s to simulate velocities commensurate with those predicted for extreme martian aeolian conditions. The sabot impelling method permitted study of individual impacts without the masking effect of bed mobilization encountered in wind-tunnel studies. At these martian impact velocities, grains produced small craters formed by the ejection of several hundred grains from the bed. Unexpectedly, the craters were not elongated, despite glancing impact; the craters were very close to circular in planform

  6. Comparison of bed shear under non-breaking and breaking solitary waves

    Digital Repository Service at National Institute of Oceanography (India)

    JayaKumar, S.; Baldock, T.E.

    varying between 0.12 and 0.69. Analytical modeling was carried out to predict shear stresses using Fourier and convolution integration methods. This paper presents comparison of the measured and predicted bed shear stress or skin friction stress, together...

  7. The consequences of granulate heterogeneity towards breakage and attrition upon fluid-bed drying

    NARCIS (Netherlands)

    Nieuwmeyer, Florentine; Maarschalk, Kees van der Voort; Vromans, Herman

    2008-01-01

    High-shear granulated lactose granulates were dried in it fluid-bed dryer at various conditions. Granules were characterized by water content and size analysis. It is shown that the drying process is very dynamic in terms of growth and breakage phenomena. Granular size heterogeneity, composition and

  8. Drying of suspension and pastes in fluidized bed of inert particles

    Directory of Open Access Journals (Sweden)

    ZORANA LJ. ARSENIJEVIC

    2000-12-01

    Full Text Available A fluid bed dryer with inert particles was used for the drying of suspensions and pastes. The effects of the operating conditions on the dryer throughput and on the product quality were investigated. Experiments were performed in a cylindrical column 215 mm in diameter and 1200 mm in height with 0.925 mm diameter glass spheres as the fluidizing media. Cineb fungicide, copper hydroxide and pure water were used as the feed material. With respect to the main efficiency criteria, i.e., specific water evaporation rate, specific heat consumption and specific air consumption, a fluid bed dryer with inert particles represents a very attractive alternative to other drying technologies. A high drying efficiency results from the large contact area and from the large temperature difference between the inlet and outlet air. A rapid mixing of the particles, due to aggregative fluidization and mechanical agitation, leads to nearly isothermal conditions throughout the bed. In our experiments, suspensions and very dense pastes were successfully treated. Suspension and product hold-up in the bed varies between 6 and 8 % by mass and a product with the same particle size as the raw material is obtained.

  9. Separating bathymetric data representing multiscale rhythmic bed forms: A geostatistical and spectral method compared

    NARCIS (Netherlands)

    Van Dijk, T.A.G.P.; Lindenbergh, R.C.; Egberts, P.J.P.

    2008-01-01

    The superimposition of rhythmic bed forms of different spatial scales is a common and natural phenomenon on sandy seabeds. The dynamics of such seabeds may interfere with different offshore activities and are therefore of interest to both scientists and offshore developers. State-of-the-art echo sou

  10. Coal-bed methane water effects on dill and essential oils

    Science.gov (United States)

    Pumping water from coal seams decreases the pressure in the seam and in turn releases trapped methane; this is the most common and economic way of methane extraction. The water that is pumped out is known as coal-bed methane water (CBMW), which is high in sodium and other salts. In past 25 years, th...

  11. Analysis of responses to kallidin, DABK, and DAK in feline hindlimb vascular bed.

    Science.gov (United States)

    Santiago, J A; Garrison, E A; Champion, H C; Smith, R E; Del Rio, O; Kadowitz, P J

    1995-12-01

    Responses to kallidin, des-Arg9-bradykinin (DABK), and des-Arg10-kallidin (DAK) were investigated in the hindlimb vascular bed of the cat under constant-flow conditions. Injections of kallidin, DABK, and DAK into the hindlimb perfusion circuit produced dose-dependent vasodilator responses in the hindlimb vascular bed. Vasodilator responses to kallidin and bradykinin (BK) were similar in magnitude and time course, and both peptides were approximately 100-fold more potent than DABK or DAK. Responses to kallidin were decreased by the kinin B2 antagonist, HOE 140, whereas responses to DABK and DAK were reduced by des-Arg9[Leu8]BK, a kinin B1-receptor antagonist. N omega-nitro-L-arginine methyl ester (L-NAME) reduced vasodilator responses to kallidin, DABK, and DAK, whereas meclofenamate, atropine, and U-37883A, a vascular selective ATP-sensitive K+ (K+ATP) channel-blocking agent, did not alter responses to the three peptides. These data suggest that both kinin B1 and B2 receptors are normally present in the hindlimb vascular bed. These data also suggest that kinin B1 and B2 receptor-mediated vasodilator responses are mediated by the release of nitric oxide and that the activation of K+ATP channels or muscarinic receptors, or the release of vasodilator prostaglandins play little if any role in mediating responses to kallidin, DABK, or DAK in the hindlimb vascular bed of the cat.

  12. ELECTRODEPOSITION OF COPPER IONS ON FIXED BED ELECTRODES: KINETIC AND HYDRODYNAMIC STUDY

    Directory of Open Access Journals (Sweden)

    L.A.M. Ruotolo

    2002-03-01

    Full Text Available The kinetic and hydrodynamic behaviour of a fixed-bed electrochemical reactor was studied in terms of current efficiency (CE and energy efficiency (EE. In the kinetic experiments the effects of fixed bed thickness (L, current density (i and initial concentration of copper (C0 were studied. In the hydrodynamic experiments the permeability (k of the electrode and the coefficient for inertial forces (c were also studied as functions of the applied current density. At low current densities and bed thicknesses greater than 1.0 cm, negative CE and EE were observed as a consequence of the dissolution of the porous matrix. At high current densities low CE and EE were observed and a powdery deposit was formed on the surface of the particles. From the results of the kinetic study bed thickness and the range of current densities employed in the hydrodynamic experiments were chosen. In these experiments the electrodeposition process continued until the whole electrode had been clogged and no more electrolyte could pass through it. The relationship between pressure drop and flow rate was well described by the Forchheimer equation. It was observed that the reduction in porosity due to copper electrodeposition causes the flow rate to decrease because of the decrease in electrode permeability, but it had no influence on current efficiency.

  13. Flow of River Tigris and its Effect on the Bed Sediment within Baghdad, Iraq

    Science.gov (United States)

    Al-Ansari, Nadhir; Ali, Ammar A.; Al-Suhail, Qusay; Knutsson, Sven

    2015-12-01

    River Tigris is a major river in Iraq. Sediment at the bed of the river within a reach of about 18 km from the center of Baghdad upstream was investigated. Sixty five cross sections were surveyed, and 46 sediment samples were collected and analyzed. It was noticed that fine sand was dominant in the bed (90.74%). The average median size within the reach was 2.49 phi (0.177 mm), while the mean size was 2.58 phi (0.16 mm). In addition, the sediments were moderately sorted, fine skewed and leptokurtic. The size of the bed sediment decreased relative to previous investigations due to the construction of the Adhaim dam on tributary, which used to be the main sediment supplier to the Tigris River before entering Baghdad. Furthermore, the discharge of the Tigris River for the period 1983-2013 (715 m3/s) decreased by about 40% and 30%since 1983when compared with the periods 1931-1956 (1208 m3/s) and 1956-1980 (1015 m3/s), respectively, due to climate change and construction of dams upstream from Baghdad. This has decreased the capacity and the competence of the river. The bed elevation has increased compared to previous surveys. Itwas noticed that dredging operations and obstructions (e.g. fallen bridges and islands) have disturbed the flow of the river and sediment characteristics in several sites.

  14. Numerical investigation of coupled heat and mass transfer during desorption of hydrogen in metal hydride beds

    Energy Technology Data Exchange (ETDEWEB)

    Muthukumar, P.; Satheesh, A.; Madhavakrishna, U.; Dewan, Anupam [Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam (India)

    2009-01-15

    This paper presents a numerical investigation of two-dimensional coupled heat and mass transfer processes in MmNi{sub 4.6}Fe{sub 0.4} and MmNi{sub 4.6}Al{sub 0.4} based metal hydride beds of cylindrical configuration during desorption of hydrogen using a commercial software FLUENT 6.1.22. Temperature and concentration profiles at different radial locations, variation of average bed temperature and amount of hydrogen desorbed are presented at different hot fluid temperatures and bed thicknesses ranging from 30 to 50 C and 5 to 15 mm, respectively. The numerical results show that the dehydriding process for both the alloys depends on the temperature distribution in the metal hydride bed. At a given hot fluid temperature of 50 C, MmNi{sub 4.6}Fe{sub 0.4} and MmNi{sub 4.6}Al{sub 0.4} desorb the maximum hydrogen of about 1.11 and 1.28 wt%, respectively at the supply conditions of 30 bar and 25 C. The present computational results are also compared with the experimental data reported in the literature and a good agreement was found between the two. (author)

  15. Alarm pheromones and chemical communication in nymphs of the tropical bed bug Cimex hemipterus (Hemiptera: Cimicidae.

    Directory of Open Access Journals (Sweden)

    H Christoph Liedtke

    Full Text Available The recent resurge of bed bug infestations (Cimex spp.; Cimicidae and their resistance to commonly used pesticides calls for alternative methods of control. Pheromones play an important role in environmentally sustainable methods for the management of many pest insects and may therefore be applicable for the control of bed bugs. The tropical bed bug, Cimex hemipterus, is a temporary ectoparasite on humans and causes severe discomfort. Compared to the common bed bug, Cimex lectularius, little is known about the chemical signalling and pheromone-based behaviour of the tropical species. Here, we show that the antennal morphology and volatile emission of C. hemipterus closely resembles those of C. lectularius and we test their behavioural responses to conspecific odour emissions. Two major volatiles are emitted by male, female and nymph C. hemipterus under stress, (E-2-hexenal and (E-2-octenal. Notably, nymph emissions show contrasting ratios of these compounds to adults and are further characterized by the addition of 4-oxo-(E-2-hexenal and 4-oxo-(E-2-octenal. The discovery of this nymph pheromone in C. hemipterus is potentially the cause of a repellent effect observed in the bio-tests, where nymph odours induce a significantly stronger repellent reaction in conspecifics than adult odours. Our results suggest that pheromone-based pest control methods developed for C. lectularius could be applicable to C. hemipterus, with the unique nymph blend showing promising practical properties.

  16. Effects of periodicity on flow and dispersion through closely packed fixed beds of spheres

    Science.gov (United States)

    Reynolds, A. M.

    2002-02-01

    A lattice-Boltzmann formulation is used to investigate the effects of ``periodicity'' (geometry) on fluid flow and tracer-particle dispersion through fixed beds of spheres comprising of closely packed layers. In the ``period-1'' arrangement, spheres in the adjacent layers contact at their poles while the ``period-2'' and ``period-3'' arrangements correspond to hexagonal and faced-centered cubic close packing. For all three packing arrangements, there is a transition with increasing Reynolds number from a power law to a log-normal distribution of kinetic energies and, velocity and vorticity become more closely aligned giving rise to helical tracer-particle trajectories. It is suggested that these flow characteristics, unlike the stability of flow and the distribution of helicity, are largely insensitive to geometry, even when the geometry creates direct channels through the pack bed orientated along the gradient in applied pressure. For steady flows and strongly turbulent flows, such channels are predicted to provide direct routes for dispersion through a packed bed, while for weakly turbulent flows they influence dispersion primarily by destabilizing the flow and thereby promoting dispersion throughout a bed. The dispersion of tracer-particles released from a source located on or close to a ``stagnation streamline'' is predicted to be faster than ballistic in the near field and the transition to long-time Fickian diffusion is predicted to be distinguished by a regime of subdiffusion.

  17. Techniques of tumour bed boost irradiation in breast conserving therapy: Current evidence and suggested guidelines

    International Nuclear Information System (INIS)

    Breast conservation surgery followed by external beam radiotherapy to breast has become the standard of care in management of early carcinoma breast. A boost to the tumour bed after whole breast radiotherapy is employed in view of the pattern of tumour bed recurrences in the index quadrant and was particularly considered in patients with some adverse histopathological characteristics such as positive margins, extensive intraductal carcinoma (EIC), lymphovascular invasion (LVI), etc. There is however, now, a conclusive evidence of improvement in local control rates after a boost radiotherapy dose in patients even without such factors and for all age groups. The maximum absolute reduction of local recurrences by the addition of boost is especially seen in young premenopausal patients. At the same time, the addition of boost is associated with increased risk of worsening of cosmesis and no clear cut survival advantage. Radiological modalities such as fluoroscopy, ultrasound and CT scan have aided in accurate delineation of tumour bed with increasing efficacy. A widespread application of these techniques might ultimately translate into improved local control with minimal cosmetic deficit. The present article discusses the role of radiotherapy boost and the means to delineate and deliver the same, identify the high risk group, optimal technique and the doses and fractionations to be used. It also discusses the extent of adverse cosmetic outcome after boost delivery, means to minimise it and relevance of tumour bed in present day scenario of advanced radiotherapy delivery techniques like (IMRT)

  18. Techniques of tumour bed boost irradiation in breast conserving therapy: Current evidence and suggested guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Jalali, Rakesh; Singh, Suruchi; Budrukkar, Ashwini [Tata Memorial Hospital, Mumbai (India)

    2007-10-15

    Breast conservation surgery followed by external beam radiotherapy to breast has become the standard of care in management of early carcinoma breast. A boost to the tumour bed after whole breast radiotherapy is employed in view of the pattern of tumour bed recurrences in the index quadrant and was particularly considered in patients with some adverse histopathological characteristics such as positive margins, extensive intraductal carcinoma (EIC), lymphovascular invasion (LVI), etc. There is however, now, a conclusive evidence of improvement in local control rates after a boost radiotherapy dose in patients even without such factors and for all age groups. The maximum absolute reduction of local recurrences by the addition of boost is especially seen in young premenopausal patients. At the same time, the addition of boost is associated with increased risk of worsening of cosmesis and no clear cut survival advantage. Radiological modalities such as fluoroscopy, ultrasound and CT scan have aided in accurate delineation of tumour bed with increasing efficacy. A widespread application of these techniques might ultimately translate into improved local control with minimal cosmetic deficit. The present article discusses the role of radiotherapy boost and the means to delineate and deliver the same, identify the high risk group, optimal technique and the doses and fractionations to be used. It also discusses the extent of adverse cosmetic outcome after boost delivery, means to minimise it and relevance of tumour bed in present day scenario of advanced radiotherapy delivery techniques like (IMRT)

  19. Investigation of hydrodynamic parameters in a novel expanded bed configuration: local axial dispersion characterization and an empirical correlation study

    Directory of Open Access Journals (Sweden)

    E. S. Taheri

    2012-12-01

    Full Text Available Study of liquid behavior in an expanded bed adsorption (EBA system is important for understanding, modeling and predicting nanobioproduct/biomolecule adsorption performance in such processes. In this work, in order to analyze the local axial dispersion parameters, simple custom NBG (Nano Biotechnology Group expanded bed columns with 10 and 26 mm inner diameter were modified by insertion of sampling holes. Based on this configuration, the particles and liquid can be withdrawn directly from various axial positions of the columns. Streamline DEAE particles were used as solid phase in this work. The effects of factors such as liquid velocity, viscosity, settled bed height and column diameter on the hydrodynamic parameters were investigated. Local bed voidages in different axial bed positions were measured by a direct procedure within the column with 26 mm diameter. Increasing trend of voidage with velocity at a certain position of the bed and with bed height at a certain degree of expansion was observed. Residence time distribution (RTD analysis at various bed points showed approximately uniform hydrodynamic behavior in the column with 10 mm diameter while a decreasing trend of mixing/dispersion along the bed height at a certain degree of expansion was seen in the column with 26 mm diameter. Also lower mixing/dispersion occured in the smaller diameter column. Finally, a combination of two empirical correlations proposed by Richardson-Zaki and Tong-Sun was successfully employed for identification of the bed voidage at various bed heights (RSSE=99.9%. Among the empirical correlations presented in the literatures for variation of the axial dispersion coefficient, the Yun correlation gave good agreement with our experimental data (RSSE=87% in this column.

  20. Prospect evaluation of BED 3 and Sitra oilfields, Abu Gharadig Basin, North Western Desert, Egypt

    Science.gov (United States)

    Salem, Ibrahim; Ghazala, Hosni; El Diasty, Waleed

    2015-12-01

    The occurrence of hydrocarbons is closely linked to the elements of petroleum system history of the BED 3 and Sitra 8 oilfields, which has created multiple reservoir and seal combinations. BED 3 Field and Sitra concessions occupy the northwestern part of the Abu Gharadig Basin and extends between latitudes 29°45‧ and 30°05‧N and longitudes 27°30‧ and 28°10‧E. The comprehensive integration of the geo-related data and the interpretation of the well logging, geochemical, seismic data in time domain and depth and sealing mechanisms explain the occurrence of hydrocarbons in some certain reservoirs during cretaceous age and other reservoirs in the same fields don't have any hydrocarbon accumulation. Detailed seismic data interpretation was performed for the target units of BED 3 and Sitra 8 oilfields in time domain and converted to depth domain. Sitra 8 Field is a three-way dip closure bounded by NW-SE faults while BED 3 field is represented by a WNW-ESE trending horst dipping to the east. The Albian-Cenomanian Kharita Formation has a high energy shallow marine shelf environment and considered as the main pay zone in the BED 3 oilfield. On the other hand, Kharita sands are dry in the Sitra 8 Field. Also, the shallow marine shale, sandstone, limestone and dolomite interbeds of the Abu Roash G Member are another hydrocarbon bearing reservoir in the Sitra 8 Field. Sealing mechanisms were applied to explain why certain reservoirs have hydrocarbon and others don't. Allan's juxtaposition diagram for the main faults in the study area shows that Kharita sands in BED 3 area have excellent juxtaposition as Kharita juxtapose to upper Bahariya and intra Bahariya, which consist of shale and limestone. Abu Roash G sands in BED 3 area have bad juxtaposition as the Abu Roash G juxtapose to Abu Roash C sand (sand juxtaposed sand). Allan's diagram shows that the Abu Roash G reservoir (main target) in Sitra 8 is juxtaposing Abu Roash D which is composed of limestone and shale

  1. Continuous, packed-bed, enzymatic bioreactor production and stability of feruloyl soy glycerides

    Science.gov (United States)

    The synthesis of feruloyl soy glycerides was demonstrated on a pilot-scale (1 metric ton/year) in a continuous, four-column series, packed-bed, enzymatic bioreactor. Ethyl ferulate and soybean oil were combined and converted at 3.5 kg/d over Candida antartica lipase B immobilized on an acrylic rein ...

  2. Modeling river dune development and dune transition to upper stage plane bed

    NARCIS (Netherlands)

    Naqshband, S.; Duin, van O.J.M.; Ribberink, J.S.; Hulscher, S.J.M.H.

    2016-01-01

    Large asymmetric bedforms known as dunes commonly dominate the bed of sand rivers. Due to the turbulence generation over their stoss and lee sides, dunes are of central importance in predicting hydraulic roughness and water levels. During floods in steep alluvial rivers, dunes are observed to grow r

  3. Characterization and CFD-modeling of the hydrodynamics of a prismatic spouted bed apparatus

    NARCIS (Netherlands)

    Gryczka, O.; Heinrich, S.; Deen, N.G.; Sint Annaland, van M.; Kuipers, J.A.M.; Jacob, M.; Mörl, L.

    2009-01-01

    Recently the importance of spouted bed technology has significantly increased in the context of drying processes as well as granulation, agglomeration or coating processes. However, the understanding of the complex interactions within and between the single phases is still low and needs further impr

  4. Balance Analysis of Profit and Loss on Exploiting Coal-Bed Gas in China

    Institute of Scientific and Technical Information of China (English)

    肖建洪; 苗建国; 陈晓慧

    2001-01-01

    Models about four aspects according to the balance principle and practice in China were established, which involve the minimum production scale, alert production scale, safe running scale, and the goal production scale for specified profit level. It provides an effective quantitative analyzing method for the investors of coal-bed gas exploitation project.

  5. "Ten in a Bed": Literacy, Intermediality and the Potentials of Low-Tech

    Science.gov (United States)

    Beswick, Katie

    2016-01-01

    "Ten in Bed" was a project led by participatory arts organisation Phakama, in partnership with Queen Mary University of London. Over an eight-week period we ran a series of intermedial arts workshops and staged a performance with under five-year-olds and their families at a community centre in Bethnal Green, London. We attempted to…

  6. FLUIDIZED BED STEAM REFORMING FOR TREATMENT AND IMMOBILIZATION OF LOW-ACTIVITY WASTE

    Energy Technology Data Exchange (ETDEWEB)

    HEWITT WM

    2011-04-08

    This report is one of four reports written to provide background information regarding immobilization technologies remaining under consideration for supplemental immobilization of Hanford's low-activity waste. This paper provides the reader a general understanding of fluidized bed steam reforming and its possible application to treat and immobilize Hanford low-activity waste.

  7. SWASH ZONE BED LEVEL CHANGES AND SEDIMENT ENTRAINMENT AT THE SURF-SWASH BOUNDARY

    DEFF Research Database (Denmark)

    Jensen, Stine Gro; Aagaard, Troels; Baldock, Tom

    2010-01-01

    detailed data on water levels and bed elevations in the swash zone. Water levels derived from the pressure transducers show that swash zone characteristics vary from the upper to lower swash. Using pressure transducers in the swash zone coupled with measurements of the hydrodynamics and sediment...

  8. Fluidized Bed Steam Reforming For Treatment And Immobilization Of Low-Activity Waste

    International Nuclear Information System (INIS)

    This report is one of four reports written to provide background information regarding immobilization technologies remaining under consideration for supplemental immobilization of Hanford's low-activity waste. This paper provides the reader a general understanding of fluidized bed steam reforming and its possible application to treat and immobilize Hanford low-activity waste.

  9. Absorption and desorption of hydrogen with particle beds of several zirconium alloys

    Science.gov (United States)

    Mitsuishi, N.; Fukada, S.

    1990-12-01

    For the storage of tritium and the recovery of hydrogen isotopes from inert gas mixtures in the fuel cycle of a D-T fusion reactor, metallic particle beds of elementary zirconium and vanadium, and intermetallic compounds of zirconium such as ZrV 2, Zr(V 0.83Fe 0.17) 2 and ZrNi are compared. One of the samples is packed in a quartz column, through which H 2-Ar gas mixtures at 50-600°C for absorption or Ar gas at 400-800°C for desorption is passed. In conclusion: activation of the Zr, ZrNi and ZrV 2 beds is easier than activation of the Zr(V 0.83Fe 0.17) 2 bed; any of the beds of the compounds can absorb hydrogen up to a concentration of less than 1 ppm at the outlet at 100°C; the hydrogen absorption rate of ZrV 2 is enhanced by the addition of iron to it; the amount of the hydrogen storage in ZrNi is the highest in this experimental condition; and absorption and desorption rates of the Zr(V 0.83Fe 0.17) 2 alloy are the fastest.

  10. The definitive and intermediate hosts of Fasciola hepatica in the natural watercress beds in central France.

    Science.gov (United States)

    Rondelaud, D; Vignoles, P; Abrous, M; Dreyfuss, G

    2001-06-01

    Field investigations were carried out over a two-year period in 52 natural watercress beds located in the Limousin region of central France to list the mammal and bird species that frequented these sites. This enabled detection of the definitive hosts of Fasciola hepatica and determination of the prevalence of natural infection in snails. A total of 13 mammal and five bird species were listed in these watercress beds. Adult flukes were found in Lepus capensis (39.2%), Oryctolagus cuniculus (42.0%), and Sylvilagus floridanus (25.0%). No infection with F. hepatica was noted in the five species of rodents studied. Snails infected with F. hepatica were found in 14 watercress beds. The global prevalence of natural infection was 1.1% in Lymnaea truncatula and 0.3% in L. glabra. Among the other trematode larval forms detected, the most frequent was Haplometra cylindracea (0.5%). In the Limousin region, the presence of hares and rabbits in watercress beds ensured the continuation of the F. hepatica life cycle and permitted the subsequent infection of humans when this wild watercress was eaten. PMID:11411948

  11. Numerical study on wave dynamics and wave-induced bed erosion characteristics in Potter Cove, Antarctica

    Science.gov (United States)

    Lim, Chai Heng; Lettmann, Karsten; Wolff, Jörg-Olaf

    2013-12-01

    Wave generation, propagation, and transformation from deep ocean over complex bathymetric terrains to coastal waters around Potter Cove (King George Island, South Shetland Islands, Antarctica) have been simulated for an austral summer month using the Simulating Waves Nearshore (SWAN) wave model. This study aims to examine and understand the wave patterns, energy fluxes, and dissipations in Potter Cove. Bed shear stress due to waves is also calculated to provide a general insight on the bed sediment erosion characteristics in Potter Cove.A nesting approach has been implemented from an oceanic scale to a high-resolution coastal scale around Potter Cove. The results of the simulations were compared with buoy observations obtained from the National Data Buoy Center, the WAVEWATCH III model results, and GlobWave altimeter data. The quality of the modelling results has been assessed using two statistical parameters, namely the Willmott's index of agreement D and the bias index. Under various wave conditions, the significant wave heights at the inner cove were found to be about 40-50 % smaller than the ones near the mouth of Potter Cove. The wave power in Potter Cove is generally low. The spatial distributions of the wave-induced bed shear stress and active energy dissipation were found to be following the pattern of the bathymetry, and waves were identified as a potential major driving force for bed sediment erosion in Potter Cove, especially in shallow water regions. This study also gives some results on global ocean applications of SWAN.

  12. The suspended sediment transport equation and its near-bed sediment flux

    Institute of Scientific and Technical Information of China (English)

    LI RuiJie; LUO Feng; ZHU WenJin

    2009-01-01

    The suspended sediment transport equation and its near-bed sediment flux are one of the key prob-lems of sediment transport research under nonequilibrium condition. Based on the three-dimensional primitive suspended transport equation, the two-dimensional suspended sediment transport equation is deduced. The derived process indicates that the physical essence of the near-bed sediment flux is right the bottom boundary condition for the suspended sediment transport equation. This paper ana-lyzes the internal relations between the two methods of sediment carrying capacity and shear stress in common use, points out the consistency of these two methods in terms of form and physical meaning, and unifies these two methods theoretically. Furthermore, based on the analysis and comparison of the expressions of the near-bed sediment flux, this paper summarizes some problems to which attention should be paid, thus offering a novel approach to the study and the solution of the problems of sus-pended sediment transport and exchange flux of near-bed water sediment.

  13. The suspended sediment transport equation and its near-bed sediment flux

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The suspended sediment transport equation and its near-bed sediment flux are one of the key problems of sediment transport research under nonequilibrium condition. Based on the three-dimensional primitive suspended transport equation, the two-dimensional suspended sediment transport equation is deduced. The derived process indicates that the physical essence of the near-bed sediment flux is right the bottom boundary condition for the suspended sediment transport equation. This paper analyzes the internal relations between the two methods of sediment carrying capacity and shear stress in common use, points out the consistency of these two methods in terms of form and physical meaning, and unifies these two methods theoretically. Furthermore, based on the analysis and comparison of the expressions of the near-bed sediment flux, this paper summarizes some problems to which attention should be paid, thus offering a novel approach to the study and the solution of the problems of suspended sediment transport and exchange flux of near-bed water sediment.

  14. Packed Bed Bioreactor for the Isolation and Expansion of Placental-Derived Mesenchymal Stromal Cells.

    Science.gov (United States)

    Osiecki, Michael J; Michl, Thomas D; Kul Babur, Betul; Kabiri, Mahboubeh; Atkinson, Kerry; Lott, William B; Griesser, Hans J; Doran, Michael R

    2015-01-01

    Large numbers of Mesenchymal stem/stromal cells (MSCs) are required for clinical relevant doses to treat a number of diseases. To economically manufacture these MSCs, an automated bioreactor system will be required. Herein we describe the development of a scalable closed-system, packed bed bioreactor suitable for large-scale MSCs expansion. The packed bed was formed from fused polystyrene pellets that were air plasma treated to endow them with a surface chemistry similar to traditional tissue culture plastic. The packed bed was encased within a gas permeable shell to decouple the medium nutrient supply and gas exchange. This enabled a significant reduction in medium flow rates, thus reducing shear and even facilitating single pass medium exchange. The system was optimised in a small-scale bioreactor format (160 cm2) with murine-derived green fluorescent protein-expressing MSCs, and then scaled-up to a 2800 cm2 format. We demonstrated that placental derived MSCs could be isolated directly within the bioreactor and subsequently expanded. Our results demonstrate that the closed system large-scale packed bed bioreactor is an effective and scalable tool for large-scale isolation and expansion of MSCs. PMID:26660475

  15. Aerobic mineralization of MTBE and tert-butyl alcohol by stream-bed sediment microorganisms

    Science.gov (United States)

    Bradley, P.M.; Landmeyer, J.E.; Chapelle, F.H.

    1999-01-01

    Microorganisms indigenous to the stream-bed sediments at two gasoline- contaminated groundwater sites demonstrated significant mineralization of the fuel oxygenates, methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA). Up to 73% of [U-14C]-MTBE and 84% of [U-14C]-TBA were degraded to 14CO2 under mixed aerobic/anaerobic conditions. No significant mineralization was observed under strictly anaerobic conditions. The results indicate that, under the mixed aerobic/anaerobic conditions characteristic of stream-bed sediments, microbial processes may provide a significant environmental sink for MTBE and TBA delivered to surface water bodies by contaminated groundwater or by other sources.Microorganisms indigenous to the stream-bed sediments at two gasoline-contaminated groundwater sites demonstrated significant mineralization of the fuel oxygenates, methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA). Up to 73% of [U-14C]-MTBE and 84% of [U-14C]-TBA were degraded to 14CO2 under mixed aerobic/anaerobic conditions. No significant mineralization was observed under strictly anaerobic conditions. The results indicate that, under the mixed aerobic/anaerobic conditions characteristic of stream-bed sediments, microbial processes may provide a significant environmental sink for MTBE and TBA delivered to surface water bodies by contaminated groundwater or by other sources.

  16. Application of Moving Bed Biofilm Process for Biological Organics and Nutrients Removal from Municipal Wastewater

    Directory of Open Access Journals (Sweden)

    M. Kermani

    2008-01-01

    Full Text Available In this study, experiments have been conducted to evaluate the organics and nutrients removal from synthetic wastewater by a laboratory scale moving bed biofilm process. For nutrients removal, moving bed biofilm process has been applied in series with anaerobic, anoxic and aerobic units in four separate reactors. Moving bed biofilm reactors were operated continuously at different loading rates of nitrogen and Phosphorus. During optimum conditions, close to complete nitrification with average ammonium removal efficiency of 99.72% occurred in the aerobic reactor. In the aerobic reactor, the average specific nitrification rate was 1.8 g NOx-N kg VSS-1 h-1. The results of the average effluent soluble COD concentration from each reactor showed that denitrification process in the second anoxic reactor consumed most of the biodegradable organic matter. As seen from the results, denitrification rate has increased with increasing NOx-N loading in the second anoxic reactor. The aerobic phosphate removal rate showed a good correlation to the anaerobic phosphate release rate. Moreover, phosphate removal rate showed a strong correlation to the phosphate loading rate in the aerobic reactor. In optimum conditions, the average SCOD, total nitrogen and phosphorus removal efficiencies were 96.9, 84.6 and 95.8%, respectively. This study showed that the moving bed biofilm process could be used as an ideal and efficient option for the total nutrient removal from municipal wastewater.

  17. Packed Bed Bioreactor for the Isolation and Expansion of Placental-Derived Mesenchymal Stromal Cells.

    Science.gov (United States)

    Osiecki, Michael J; Michl, Thomas D; Kul Babur, Betul; Kabiri, Mahboubeh; Atkinson, Kerry; Lott, William B; Griesser, Hans J; Doran, Michael R

    2015-01-01

    Large numbers of Mesenchymal stem/stromal cells (MSCs) are required for clinical relevant doses to treat a number of diseases. To economically manufacture these MSCs, an automated bioreactor system will be required. Herein we describe the development of a scalable closed-system, packed bed bioreactor suitable for large-scale MSCs expansion. The packed bed was formed from fused polystyrene pellets that were air plasma treated to endow them with a surface chemistry similar to traditional tissue culture plastic. The packed bed was encased within a gas permeable shell to decouple the medium nutrient supply and gas exchange. This enabled a significant reduction in medium flow rates, thus reducing shear and even facilitating single pass medium exchange. The system was optimised in a small-scale bioreactor format (160 cm2) with murine-derived green fluorescent protein-expressing MSCs, and then scaled-up to a 2800 cm2 format. We demonstrated that placental derived MSCs could be isolated directly within the bioreactor and subsequently expanded. Our results demonstrate that the closed system large-scale packed bed bioreactor is an effective and scalable tool for large-scale isolation and expansion of MSCs.

  18. Temperature and Time Requirements for Controlling Bed Bugs (Cimex lectularius under Commercial Heat Treatment Conditions

    Directory of Open Access Journals (Sweden)

    Stephen A. Kells

    2011-08-01

    Full Text Available Developing effective alternative approaches for disinfesting bed bugs from residential spaces requires a balance between obtaining complete insect mortality, while minimizing costs and energy consumption. One method of disinfestation is the application of lethal high temperatures directly to rooms and contents within a structure (termed whole-room heat treatments. However, temperature and time parameters for efficacy in whole-room heat treatments are unknown given the slower rate of temperature increase and the probable variability of end-point temperatures within a treated room. The objective of these experiments was to explore requirements to produce maximum mortality from heat exposure using conditions that are more characteristic of whole-room heat treatments. Bed bugs were exposed in an acute lethal temperature (LTemp trial, or time trials at sub-acute lethal temperatures (LTime. The lethal temperature (LTemp99 for adults was 48.3 °C, while LTemp99 for eggs was 54.8 °C. Adult bed bugs exposed to 45 °C had a LTime99 of 94.8 min, while eggs survived 7 h at 45 °C and only 71.5 min at 48 °C. We discuss differences in exposure methodologies, potential reasons why bed bugs can withstand higher temperatures and future directions for research.

  19. Diapers and underpads, Part 2: Cost outcomes.

    Science.gov (United States)

    Brown, D S

    1994-01-01

    A randomized clinical trial was conducted at three acute care facilities between August and December 1993 to compare cost outcomes between patients managed with diapers or with underpads. The 166 patients were divided into five groups: polymer or nonpolymer underpads, polymer or nonpolymer diapers, and cloth underpads. Among other results, the average number of nonpolymer underpads used (3.4) compared to other products used (1.4 polymer underpads, 1.1 cloth underpads, 1.0 nonpolymer diapers, 1.0 polymer diapers) quantified nurses' perceptions that nonpolymer pads were not as effective as their polymer counterparts in absorbing incontinence. The nonpolymer underpad was, however, the least expensive of the products studied, even taking into account the volume of product used. The nonpolymer underpad group also took the most time for cleanup. The cloth underpad group consistently used all of the linen items, suggesting that complete bed changes were necessary. The polymer underpad group consistently used the least linen, suggesting that the incontinence episodes were successfully contained by the product. When all costs were combined for time (at $13.50 hourly aide wage), linen use and product type, there was a statistically significant difference between the five treatment groups (F 9.3, p diaper products were higher than either the polymer or cloth underpad groups. Recommendations, based on both parts 1 and 2 of this study are that the polymer diaper is the product of choice for the ambulatory patient, and the polymer underpad is the product of choice for the bedridden patient. The nonpolymer underpad should no longer have a place in incontinence management. PMID:7546107

  20. Deep trophoblast invasion and spiral artery remodelling in the placental bed of the lowland gorilla

    DEFF Research Database (Denmark)

    Pijnenborg, R; Vercruysse, L; Carter, Anthony Michael

    2011-01-01

    In contrast to baboon or rhesus macaque, trophoblast invasion in the human placental bed occurs by the interstitial as well as the endovascular route and reaches as deep as the inner myometrium. We here describe two rare specimens of gorilla placenta. In the light of recent findings in the chimpa......In contrast to baboon or rhesus macaque, trophoblast invasion in the human placental bed occurs by the interstitial as well as the endovascular route and reaches as deep as the inner myometrium. We here describe two rare specimens of gorilla placenta. In the light of recent findings...... in the chimpanzee, we postulated the occurrence of deep invasion in gorilla pregnancy. Tissues were processed for histology (PAS, orcein), lectin staining (Ulex europaeus agglutinin 1) and immunohistochemistry (cytokeratin 7/17, α-actin). A specimen of young but undetermined gestational age included deep placental...... bed tissue, showing interstitial and spiral artery invasion of the inner myometrium as well as the decidua. The cell density and depth of trophoblast invasion was equivalent to a human placental bed of 10-14 weeks. Intraluminal trophoblasts were not seen in any of the invaded vessels, allowing...

  1. Recycling manure as cow bedding: Potential benefits and risks for UK dairy farms.

    Science.gov (United States)

    Leach, Katharine A; Archer, Simon C; Breen, James E; Green, Martin J; Ohnstad, Ian C; Tuer, Sally; Bradley, Andrew J

    2015-11-01

    Material obtained from physical separation of slurry (recycled manure solids; RMS) has been used as bedding for dairy cows in dry climates in the US since the 1970s. Relatively recently, the technical ability to produce drier material has led to adoption of the practice in Europe under different climatic conditions. This review collates the evidence available on benefits and risks of using RMS bedding on dairy farms, with a European context in mind. There was less evidence than expected for anecdotal claims of improved cow comfort. Among animal health risks, only udder health has received appreciable attention. There are some circumstantial reports of difficulties of maintaining udder health on RMS, but no large scale or long term studies of effects on clinical and subclinical mastitis have been published. Existing reports do not give consistent evidence of inevitable problems, nor is there any information on clinical implications for other diseases. The scientific basis for guidelines on management of RMS bedding is limited. Decisions on optimum treatment and management may present conflicts between controls of different groups of organisms. There is no information on the influence that such 'recycling' of manure may have on pathogen virulence. The possibility of influence on genetic material conveying antimicrobial resistance is a concern, but little understood. Should UK or other non-US farmers adopt RMS, they are advised to do so with caution, apply the required strategies for risk mitigation, maintain strict hygiene of bed management and milking practices and closely monitor the effects on herd health. PMID:26388545

  2. Mapping seagrass beds and coral reefs in the coastal region of Vietnam using VNREDSAT-1 data

    Science.gov (United States)

    Lau, K. V.; Chen, C. F.; Nguyen, S. T.; Chen, C. R.; Tong Phuoc, H. S.; Nguyen, H. H.

    2015-12-01

    Seagrass beds and coral reefs are two important ecosystems in the coastal zone. They play an important role to protect and shelter various marine organisms. Both seagrass beds and coral reefs could prevent the coastline from erosion. While seagrass stabilizes sediments and acts as a biofilter, coral reefs can control carbon dioxide in the ocean water. Besides, seagrass also provides direct food for many fish and marine animals. Therefore, mapping seagrass beds and coral reefs is very important for coastal management and conservation. In May 2013, Vietnam launched the first satellite for earth observations, called Vietnam Natural Resources, Environment and Disaster Monitoring Satellite (VNREDSAT-1). It is a great opportunity for environmental monitoring in the country using the data from this satellite. The objective of this study is to use the VNREDSAT-1 data to map seagrass beds and coral reefs in the coastal region of Ninh Hai district, Ninh Thuan province, Vietnam, where the seagrass still remains in good a condition. We processed the VNREDSAT-1 image through four steps: (1) Atmospheric correction using Second Simulation of the Satellite Signal in the Solar Spectrum radiative transfer model (6S), (2) Sun glint removal by using Hedley method, (3) Water column correction using the depth-variant index (DII) proposed by Lyzenga, and (4) Image classification using the maximum likelihood algorithm. The mapping results verified with the ground reference data showed a good overall accuracy of 75% and Kappa coefficient of 0.7. The total area of seagrass beds was approximately 323.09 ha, which mainly distributed in My Hoa and Thai An villages. The total area of coral reefs was approximately 564.42 ha, located along the coast and on outer area to seagrass and shoreline reefs. This study demonstrates the applicability of VNREDSAT-1 for underwater habitat monitoring. The results could be useful for natural resources managers to devise strategies for management and

  3. Do the coarsest bed fractions and stream power record contemporary trends in steep headwater channels?

    Science.gov (United States)

    Galia, Tomáš; Škarpich, Václav

    2016-11-01

    Three stream channels that were devoid of evidence of past debris flows and one headwater channel that contained debris flow deposits in the flysch western Carpathians, Czech Republic were selected to test relationships between in-channel processes, bed sediments, and unit stream power calculated for bankfull and Q20 flows. Contemporary depositional or erosional trends in the examined headwaters were linked with bed sediments that were represented by the coarsest cobble and boulder fraction with a mean calculated from the five largest particles. The downstream trends of the unit stream power were derived for a bankfull discharge and a well-documented 20-year flood event. In addition, the flow competences during the discharges were calculated using indirect bedload transport measurements. Downstream fining of the cobble and boulder fraction was observed in all of the studied headwaters, and unique downstream variations of the unit stream power were calculated for the longitudinal profiles. The single-thread streams that were devoid of evidence of debris flow events exhibited direct relations between the coarsest sediment size and the unit stream power, especially as calculated for the 20-year flood event and for erosional/depositional trends of the channel. The downstream coarsening of the bed material that was accompanied by an increase in the unit stream power was usually observed in the case of deeply incised (> 0.5 m above the assumed bankfull depth) channel reaches. The calculated competence of the 20-year flow was up to twofold higher than that required to entrain the largest bed particle diameters in those channel reaches, and even the bankfull flow was potentially capable of transporting the coarsest bed particles in certain of the reaches. On the other hand, some depositional channel reaches evidently led to the disconnectivity of transport of the coarsest bed material even in the case of the 20-year flood event. The longitudinal profile of the channel that

  4. 38 CFR 59.40 - Maximum number of nursing home care and domiciliary care beds for veterans by State.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Maximum number of nursing... ACQUISITION OF STATE HOMES § 59.40 Maximum number of nursing home care and domiciliary care beds for veterans... increase the total number of state home nursing home and domiciliary beds in that state beyond the...

  5. Plasma volume and biochemical changes in athletes during bed rest chronic hyperhydration

    Science.gov (United States)

    Zorbas, Yan G.; Yarullin, Vladimir L.; Denogradov, Sergei D.; Afonin, Victor B.

    Daily fluid and salt supplements (FSS) may be used to reduce plasma biochemical changes during bed rest (BR). The aim of this study was to evaluate the effect of a daily intake of FSS on plasma volume (PV) and biochemical changes during BR. Studies were done during a pre BR period of 15 days and during a BR period of 30 days. Thirty male athletes aged 22-26 years were chosen as subjects. They were divided into three groups: unsupplemented ambulatory control subjects (UACS), unsupplemented bed rested subjects (UBRS) and supplemented bed rested subjects (SBRS). The UBRS and SBRS were kept under a rigorous bed rest regime for 30 days. The SBRS took 26 ml water/kg body weight and 0.1 g sodium chloride/kg body weight daily. PV, protein, albumin, sodium (Na), Chloride (Cl), potassium (K), osmolality, creatinine, glucose, and whole blood haematocrit (Hct) and haemoglobin (Hb) concentrations were measured. PV increased significantly ( P≤0.01) while plasma protein, albumin, Na, Cl, K, glucose, creatinine, osmolality, and whole blood Hb and Hct concentration decreased significantly ( P≤0.01) in the SBRS group when compared with the UBRS group. By contrast, PV decreased significantly ( P≤0.01), while plasma protein, albumin, Na, Cl, K, glucose, creatinine, osmolality and whole blood Hct and Hb concentration increased significantly ( P≤0.01) in the UBRS group when compared with the SBRS and UACS groups. The measured parameters did not change significantly in the UACS group when compared with the baseline control values. It was concluded that a daily intake of FSS may be used to attenuate PV losses and biochemical changes in endurance trained athletes during bed rest.

  6. Gender Differences in Isokinetic Strength after 60 and 90 d Bed Rest

    Science.gov (United States)

    English, K. L.; Ploutz-Snyder, R. J.; Cromwell, R. L.; Ploutz-Snyder, L. L.

    2010-01-01

    Recent reports suggest that changes in muscle strength following disuse may differ between males and females. PURPOSE: To examine potential gender differences in strength changes following 60 and 90 d of experimental bed rest. METHODS: Isokinetic extensor and flexor strength of the knee (60deg and 180deg/s, concentric only), ankle (30deg/s, concentric and eccentric), and trunk (60deg/s, concentric only) were measured following 60 d (males: n=4, 34.5+/-9.6 y; females: n=4, 35.5+/-8.2 y) and 90 d (males: n=10, 31.4+/-4.8 y; females: n=5, 37.6+/-9.9 y) of 6-degree head-down-tilt bed rest (BR; N=23). Subjects were fed a controlled diet (55%/15%/ 30%, CHO/PRO/FAT) that maintained body weight within 3% of the weight recorded on Day 3 of bed rest. After a familiarization session, testing was conducted 6 d before BR and 2 d after BR completion. Peak torque and total work were calculated for the tests performed. To allow us to combine data from both 60- and 90-d subjects, we used a mixed-model statistical analysis in which time and gender were fixed effects and bed rest duration was a random effect. Log-transformations of strength measures were utilized when necessary in order to meet statistical assumptions. RESULTS: Main effects were seen for both time and gender (pankle, and trunk. Although males were stronger than females for most of the strength measures that we examined, only changes in trunk extensor peak torque were greater for females than males at day 60 of bed rest

  7. Bed net use and associated factors in a rice farming community in Central Kenya

    Directory of Open Access Journals (Sweden)

    Kabuage Lucy

    2009-04-01

    Full Text Available Abstract Background Use of insecticide-treated nets (ITNs continues to offer potential strategy for malaria prevention in endemic areas. However their effectiveness, sustainability and massive scale up remain a factor of socio-economic and cultural variables of the local community which are indispensable during design and implementation stages. Methods An ethnographic household survey was conducted in four study villages which were purposefully selected to represent socio-economic and geographical diversity. In total, 400 households were randomly selected from the four study villages. Quantitative and qualitative information of the respondents were collected by use of semi-structured questionnaires and focus group discussions. Results Malaria was reported the most frequently occurring disease in the area (93% and its aetiology was attributed to other non-biomedical causes like stagnant water (16%, and long rains (13%. Factors which significantly caused variation in bed net use were occupant relationship to household head (χ2 = 105.705; df 14; P = 0.000, Age (χ2 = 74.483; df 14; P = 0.000, village (χ2 = 150.325; df 6; P = 0.000, occupation (χ2 = 7.955; df 3; P = 0.047, gender (χ2 = 4.254; df 1; P = 0.039 and education levels of the household head or spouse (χ2 = 33.622; df 6; P = 0.000. The same variables determined access and conditions of bed nets at household level. Protection against mosquito bite (95% was the main reason cited for using bed nets in most households while protection against malaria came second (54%. Colour, shape and affordability were some of the key potential factors which determined choice, use and acceptance of bed nets in the study area. Conclusion The study highlights potential social and economic variables important for effective and sustainable implementation of bed nets-related programmes in Sub-Saharan Africa.

  8. Evaluation of Sleeping Comfort of Bed Mattresses using Physiological and Psychological Response Measurements

    Science.gov (United States)

    Aoi, Masataka; Kamijo, Masayoshi; Yoshida, Hiroaki

    The purpose of this study is to create a method of evaluating the quality of sleep based on the elastic properties of bed mattresses through measurement of physiological and psychological responses while sleeping. We gathered Profile of Mood States (POMS) results before and after sleep, and investigated changes in subjects' moods according to sleep. A total of 4 bed mattresses with different degrees of elasticity were prepared. They were all pocket coil mattresses. We conducted polysomnography (PSG) testing on subjects with a bioamplifier while they slept in each bed mattress, so that sleeping depth indicating the quality of sleep could be estimated. PSG is a comprehensive recording of the biophysiological changes that occur during sleep. As a result, the sleep depth of bed mattress with a high degree of elasticity increased in the PSG evaluation. Because the hip sinks in deeply from the waist, it is not easy to turn over on mattresses with a low degree of elasticity. We have therefore considered that the sleep depth of the subjects became shallow as a result. We have concluded that it is possible to estimate the quality of sleep through analysis of PSG and POMS results.

  9. Selenate removal in methanogenic and sulfate-reducing upflow anaerobic sludge bed reactors

    NARCIS (Netherlands)

    Lenz, M.; Hullebusch, van E.D.; Hommes, G.; Corvini, P.F.X.; Lens, P.N.L.

    2008-01-01

    This paper evaluates the use of upflow anaerobic sludge bed (UASB) bioreactors (30 degrees C, pH = 7.0) to remove selenium oxyanions from contaminated waters (790 mu g Se L-1) under methanogenic and sulfate-reducing conditions using lactate as electron donor. One UASB reactor received sulfate at dif

  10. Sage-Grouse and Coal-Bed Methane: Can They Coexist within the Powder River Basin?

    Science.gov (United States)

    Duncan, Michael B.

    2010-01-01

    Concerns are growing regarding the availability of sustainable energy sources due to a rapidly growing human population and a better understanding of climate change. In recent years, the United States has focused much attention on developing domestic energy sources, which include coal-bed methane (CBM). There are vast deposits of the natural gas…

  11. Conceptual design of a fluidized bed nuclear reactor: statics, dynamics and safety-related aspects

    NARCIS (Netherlands)

    Agung, A.

    2007-01-01

    In this thesis a conceptual design of an innovative high temperature reactor based on the fluidization principle (FLUBER) is proposed. The reactor should satisfy the following requirements: (a) modular and low power, (b)) large shutdown margin, (c) able to produce power when the bed of particles exp

  12. GLUT4 and glycogen synthase are key players in bed rest-induced insulin resistance

    DEFF Research Database (Denmark)

    Biensø, Rasmus Sjørup; Jørgensen, Stine Ringholm; Kiilerich, Kristian;

    2012-01-01

    To elucidate the molecular mechanisms behind physical inactivity-induced insulin resistance in skeletal muscle, 12 young, healthy male subjects completed 7 days of bed rest with vastus lateralis muscle biopsies obtained before and after. In six of the subjects, muscle biopsies were taken from bot...

  13. Model description and kinetic parameter analysis of MTBE biodegradation in a packed bed reactor

    DEFF Research Database (Denmark)

    Waul, Christopher Kevin; Arvin, Erik; Schmidt, Jens Ejbye

    2008-01-01

    A dynamic modeling approach was used to estimate in-situ model parameters, which describe the degradation of methyl tert-butyl ether (MTBE) in a laboratory packed bed reactor. The measured dynamic response of MTBE pulses injected at the reactor's inlet was analyzed by least squares and parameter...

  14. Sediment modification by seagrass beds: Muddification and sandification induced by plant cover and environmental conditions

    Science.gov (United States)

    van Katwijk, M. M.; Bos, A. R.; Hermus, D. C. R.; Suykerbuyk, W.

    2010-09-01

    Seagrasses are well-known ecosystem engineers. They reduce water dynamics and sediment resuspension, and trap fine sediments. However, exceptions of this paradigm have been reported. To test whether these exceptions could be related to plant cover and environmental conditions, we investigated sediment modification under influence of seagrass presence in various annual eelgrass ( Zostera marina) beds with varying plant cover and sediment composition. At the relatively wave-exposed, sandy sites, dense vegetation caused muddification (increase in fine sediments and organic content) of the sediments. Sparse vegetation (seagrass performance. Muddification may increase the nutrient input and, depending on the nutrient status of the system, either stimulate or reduce seagrass development. Similarly, sandification may postpone and even prevent extinction of seagrass beds when it occurs in areas that may have become too muddy for seagrass growth.

  15. Cortisol, insulin and leptin during space flight and bed rest

    Science.gov (United States)

    Stein, T. P.; Schluter, M. D.; Leskiw, M. J.

    1999-01-01

    Most ground based models for studying muscle atrophy and bone loss show reasonable fidelity to the space flight situation. However there are some differences. Investigation of the reasons for these differences can provide useful information about humans during space flight and aid in the refinement of ground based models. This report discusses three such differences, the relationships between: (i) cortisol and the protein loss, (ii) cortisol and ACTH and (iii) leptin, insulin and food intake.

  16. Humidity and Cage and Bedding Temperatures in Unoccupied Static Mouse Caging after Steam Sterilization

    OpenAIRE

    Ward, Gina M; Cole, Kelly; Faerber, Jennifer; Hankenson, F Claire

    2009-01-01

    Contemporary rodent caging and equipment often are sterilized by steam autoclaves prior to use in facilities. This work assessed the microenvironment of unoccupied static mouse cages after steam sterilization to determine when internal temperatures had cooled to levels appropriate for rodent housing. Polycarbonate static cages containing food and corncob bedding were stacked (10 rows × 7 columns) in duplicate (front and back; n = 140 cages) on a storage truck and autoclaved to 249 °F (121 °C)...

  17. Design of a bed load and driftwood filtering dam, analysis of the phenomena and hydraulic design

    OpenAIRE

    Schleiss, Anton; Speerli, J.; Pfammatter, Roger; Bianco-Riccioz, Manuella; Bianco, Philippe; De Cesare, Giovanni

    2014-01-01

    Flood protection often calls on to the realization of retention works for bed load as well as wood and debris flow. Certain relatively recent arrangements did not perform according to their intended function, what shows the complexity of the design and the implementation of such works. Adaptations were necessary to reach the security objectives. The design of a retention dam for solid materials and floating driftwood requires the consideration of numerous hydraulic and material transport proc...

  18. Lake bed environments, modern sedimentation and the glacial and post-glacial history of Windermere, UK

    OpenAIRE

    Miller, Helen

    2014-01-01

    Windermere, the largest natural lake in England, is a glacial ribbon lake located in the southeast of the Lake District. High resolution geophysical datasets, combined with sediment analysis, geomorphological mapping and historical research have been used to investigate the lake bed environments, recent sediment record of pollution and glacial and post-glacial history of the lake and surrounding catchment. The data are used to generate a present-day landscape map of Windermere, revealing...

  19. Examining time trends in the Oldowan technology at Beds I and II, Olduvai Gorge.

    Science.gov (United States)

    Kimura, Yuki

    2002-09-01

    The lithic analysis of the Bed I and II assemblages from Olduvai Gorge reveals both static and dynamic time trends in early hominids' technology from 1.8 to 1.2 m.y.a. The Bed I Oldowan (1.87-1.75 m.y.a.) is characterized by the least effort strategy in terms of raw material exploitation and tool production. The inclusion of new raw material, chert, for toolmaking in the following Developed Oldowan A (DOA, 1.65-1.53 m.y.a.) facilitated more distinctive and variable flaking strategies depending on the kind of raw materials. The unique characters of DOA are explainable by this raw material factor, rather than technological development of hominids. The disappearance of chert in the subsequent Developed Oldowan B and Acheulian (1.53-1.2 m.y.a.) necessitated a shift in tool production strategy more similar to that of Bed I Oldowan than DOA. However, the evidence suggests that Bed II hominids might have been more skillful toolmakers, intensive tool-users, and engaged in more active transport of stone tools than the Bed I predecessors. Koobi Fora hominids maintained a more static tool-using behavior than their Olduvai counterparts due mainly to a stable supply of raw materials. They differed from Olduvai hominids in terms of less battering of cores, consistent transport behavior, and few productions of side-struck flakes, indicating a regional variation of toolmaking and using practice. However, they shared with Olduvai hominids a temporal trend toward the production of larger flakes from larger cores after 1.6 m.y.a. Increased intake of animal resources and the expansion of ranging area of Homo ergaster would have led to the development of technological organization. Technological changes in the Oldowan industry are attested at Olduvai Gorge, Koobi Fora, and Sterkfontein, suggesting that it was a pan-African synchronous phenomenon, beginning at 1.5 m.y.a. PMID:12234546

  20. Validation of a model for process development and scale-up of packed-bed solid-state bioreactors

    NARCIS (Netherlands)

    Weber, F.J.; Oostra, J.; Tramper, J.; Rinzema, A.

    2002-01-01

    We have validated our previously described model for scale-up of packed-bed solid-state fermenters (Weber et al., 1999) with experiments in an adiabatic 15-dm3 packed-bed reactor, using the fungi Coniothyrium minitans and Aspergillus oryzae. Effects of temperature on respiration, growth, and sporula