Sample records for ammonia recycle percolation

  1. PRETREATMENT AND FRACTIONATION OF CORN STOVER BY AMMONIA RECYCLE PERCOLATION PROCESS. (R831645)

    EPA Science Inventory

    Corn stover was pretreated with aqueous ammonia in a flow-through column reactor, a process termed as Ammonia Recycle Percolation (ARP). The aqueous ammonia causes swelling and efficient delignification of biomass at high temperatures. The ARP process solubilizes abou...

  2. Ammonia recycled percolation as a complementary pretreatment to the dilute-acid process

    SciTech Connect

    Wu, Zhangwen, Lee, Y.Y. [Auburn Univ., AL (United States)

    1997-12-31

    A two-stage dilute-acid percolation (DA) was investigated as a pre-treatment method for switchgrass. With use of extremely low acid (0.078 wt% sulfuric acid) under moderate temperature (145-170{degrees}C), hemicellulose in switchgrass was completely solubilized showing no sugar decomposition. The treated switchgrass contained about 70% glucan and 30% lignin. The high lignin content in the treated feedstock raises a concern that it may cause a high enzyme consumption because of irreversible adsorption of cellulose enzymes to lignin. This problem may be amplified in the SSF operation since it is usually run in fed-batch mode and the residual lignin is accumulated. The DA pretreatment was, therefore, combined with the ammonia recycled percolation (ARP) process that has been proven to be effective in delignification. The combined pretreatment essentially fractionated the switchgrass into three major components. The treated feedstock contained about 90% glucan and 10% lignin. The digestibility of these samples was consistently higher than that of DA treated samples. Further study on the interaction of cellulase with xylan and that with lignin has shown that the enzymatic hydrolysis of cellulose is inhibited by lignin as well as xylan. The external xylan was found to be a noncompetitive inhibitor to cellulose hydrolysis. The cellulose used in this study was proven to have the xylanase activity. 23 refs., 8 figs., 4 tabs.

  3. Ammonia recycling enables sustainable operation of bioelectrochemical systems.

    PubMed

    Cheng, Ka Yu; Kaksonen, Anna H; Cord-Ruwisch, Ralf

    2013-09-01

    Ammonium (NH4(+)) migration across a cation exchange membrane is commonly observed during the operation of bioelectrochemical systems (BES). This often leads to anolyte acidification (pH <5.5) and complete inactivation of biofilm electroactivity. Without using conventional pH controls (dosage of alkali or pH buffers), the present study revealed that anodic biofilm activity (current) could be sustained if recycling of ammonia (NH3) was implemented. A simple gas-exchange apparatus was designed to enable continuous recycling of NH3 (released from the catholyte at pH >10) from the cathodic headspace to the acidified anolyte. Results indicated that current (110 mA or 688 Am(-3) net anodic chamber volume) was sustained as long as the NH3 recycling path was enabled, facilitating continuous anolyte neutralization with the recycled NH3. Since the microbial current enabled NH4(+) migration against a strong concentration gradient (~10-fold), a novel way of ammonia recovery from wastewaters could be envisaged. PMID:23774293

  4. Isolation of high quality lignin as a by-product from ammonia percolation pretreatment of poplar wood.

    PubMed

    Bouxin, Florent P; David Jackson, S; Jarvis, Michael C

    2014-06-01

    A two-step process combining percolation-mode ammonia pretreatment of poplar sawdust with mild organosolv purification of the extracted lignin produced high quality, high purity lignin in up to 31% yield and 50% recovery. The uncondensed fraction of the isolated lignin was up to 34%, close to that the native lignin (40%). Less lignin was recovered after pretreatment in batch mode, apparently due to condensation during the longer residence time of the solubilised lignin at elevated temperature. The lignin recovery was directly correlated with its molecular weight and its nitrogen content. Low nitrogen incorporation, observed at high ammonia concentration, may be explained by limited homolytic cleavage of ?-O-4 bonds. Ammonia concentrations from 15% to 25% (w/w) gave similar results in terms of lignin structure, yield and recovery. PMID:24755321

  5. Recycled aqueous ammonia expansion (RAAE) pretreatment to improve enzymatic digestibility of corn stalks.

    PubMed

    Zhang, Chao; Pang, Feng; Li, Bing; Xue, Shulin; Kang, Yong

    2013-06-01

    A novel lignocellulose pretreatment method using aqueous ammonia for biofuel production was proposed in this study, which named recycled aqueous ammonia expansion (RAAE). Effects of temperature, pretreatment time, water to dry corn stalks loading and flow rate of aqueous ammonia on substrate enzymatic digestibility and sugar yield were investigated. Pretreatment temperature and time are important factors that affect RAAE process. Recirculation process could improve biomass digestibility and sugar yield compared with batch experiment. After RAAE pretreatment, about 70% of the lignin was removed, while more than 90% of the cellulose was preserved in the solids, the substrate crystallinity also increased because of the removal of amorphous portion. The maximum glucan enzymatic digestibility of pretreated biomass was 85.70%, which was obtained at 85°C, 11 min, 80% water to dry corn stalks loading and 1.5L/min aqueous ammonia flow rate. PMID:23624049

  6. Recycling of Aluminum Salt Cake: Utilization of Evolved Ammonia

    NASA Astrophysics Data System (ADS)

    Li, Peng; Zhang, Mei; Teng, Lidong; Seetharaman, Seshadri

    2013-02-01

    The communication presents an extension of the leaching process of the salt cake earlier developed by the present authors. The process describes the investigations in capturing the ammonia gas evolved by hydrolysis of AlN during aqueous leaching at 373 K (100 °C) by CO2-saturated water. The product, i.e., ammonium bicarbonate which is free of chlorides, is a value-added product and can find application in the fertilizer industry. The present method has the added advantage of fixing CO2 as well.

  7. AMMONIA

    EPA Science Inventory

    This document summarizes the available information on ammonia as it relates to its effects on man and his environment. Ammonia is a ubiquitous substance and is known widely as a household cleaning agent and as a fertilizer. It plays an important role in the nitrogen cycle--in the...

  8. Pretreatment of Biomass by Aqueous Ammonia for Bioethanol Production

    NASA Astrophysics Data System (ADS)

    Kim, Tae Hyun; Gupta, Rajesh; Lee, Y. Y.

    The methods of pretreatment of lignocellulosic biomass using aqueous ammonia are described. The main effect of ammonia treatment of biomass is delignification without significantly affecting the carbohydrate contents. It is a very effective pretreatment method especially for substrates that have low lignin contents such as agricultural residues and herbaceous feedstock. The ammonia-based pretreatment is well suited for simultaneous saccharification and co-fermentation (SSCF) because the treated biomass retains cellulose as well as hemicellulose. It has been demonstrated that overall ethanol yield above 75% of the theoretical maximum on the basis of total carbohydrate is achievable from corn stover pretreated with aqueous ammonia by way of SSCF. There are two different types of pretreatment methods based on aqueous ammonia: (1) high severity, low contact time process (ammonia recycle percolation; ARP), (2) low severity, high treatment time process (soaking in aqueous ammonia; SAA). Both of these methods are described and discussed for their features and effectiveness.

  9. Process modeling of an advanced NH? abatement and recycling technology in the ammonia-based CO? capture process.

    PubMed

    Li, Kangkang; Yu, Hai; Tade, Moses; Feron, Paul; Yu, Jingwen; Wang, Shujuan

    2014-06-17

    An advanced NH3 abatement and recycling process that makes great use of the waste heat in flue gas was proposed to solve the problems of ammonia slip, NH3 makeup, and flue gas cooling in the ammonia-based CO2 capture process. The rigorous rate-based model, RateFrac in Aspen Plus, was thermodynamically and kinetically validated by experimental data from open literature and CSIRO pilot trials at Munmorah Power Station, Australia, respectively. After a thorough sensitivity analysis and process improvement, the NH3 recycling efficiency reached as high as 99.87%, and the NH3 exhaust concentration was only 15.4 ppmv. Most importantly, the energy consumption of the NH3 abatement and recycling system was only 59.34 kJ/kg CO2 of electricity. The evaluation of mass balance and temperature steady shows that this NH3 recovery process was technically effective and feasible. This process therefore is a promising prospect toward industrial application. PMID:24850444

  10. Recycling

    NSDL National Science Digital Library

    sgp0002

    2010-03-27

    You will be learning all about recycling and asking questions as you learn more about recycling. Afterward, you will be making recycling bins that we will use in our classroom. Click on each of the different links and research about recycling. Find out what recycling is, what can be recycled, and why we should recycle. As you find information, add it to the "describing wheel" that is given to you by Ms. Pollak. Answer the main question: What is recycling? Come ...

  11. Recycling.

    ERIC Educational Resources Information Center

    Sinker, Barbara

    1986-01-01

    Discusses the range of benefits resulting from recycling efforts and projects. Presents information and data related to the recycling of metals, cans, paper, fans, and plastics. Suggestions for motivating and involving youth in recycling programs are also offered. (ML)

  12. Recycling

    NSDL National Science Digital Library

    2011-04-07

    What objects can be recycled? 1. Click on link. Watch video. Recycle Guy Video 2. Click on link. Watch video. Talking Trash Video 3. Click on link. Watch video. Recycling At School Video 4. Click on link. Play game. Star Fall Recycling Game 5. Click on link. Play game. National Geographic Recycling Game 6. Click on link. Ask Ms. Owens how to do it. Things We Recycle Chart 7. Please see Miss Owens for instructions on the following ...

  13. Recovery and removal of ammonia-nitrogen and phosphate from swine wastewater by internal recycling of struvite chlorination product.

    PubMed

    Huang, Haiming; Yang, Jiang; Li, Ding

    2014-11-01

    The recovery of the total orthophosphate (PT) and removal of the total ammonia-nitrogen (TAN) from swine wastewater were investigated through a combined technology of using bittern as the magnesium source in struvite precipitation along with internal recycling of the chlorination product of the recovered struvite. Results revealed that the PT recovery efficiency and the struvite purity was mainly depended on the wastewater pH and the Mg:PT molar ratio. Co-precipitations of Mg3(PO4)2, MgKPO4, Ca3(PO4)2, and Mg(OH)2 (pH>9) were confirmed to be responsible for the decrease in the purity of struvite. The decomposition of recovered struvite by sodium hypochlorite (NaClO) was feasible. The TAN concentration of the swine wastewater was decreased to 63mg/L by internal recycling of the chlorination decomposition product for seven cycles. An economic evaluation showed that 37% of the treatment cost of the proposed process could be saved as compared with struvite precipitation using pure chemicals. PMID:25265330

  14. Recycling

    NSDL National Science Digital Library

    Miss Sykes

    2005-10-20

    Let\\'s learn how to reduce, reuse and recycle waste! BUILDING YOUR KNOWLEDGE ABOUT RECYCLING 1. Learn the abc\\'s of recycling found here A is for Air. Be sure to click on each letter of the alphabet and read what it stands for. 2. Read the Adventures of the Garbage Gremlin in this Comic Book. 3. Steel is used to build cars, household appliances and cans. Read ...

  15. Advanced Life Support Water Recycling Technologies Case Studies: Vapor Phase Catalytic Ammonia Removal and Direct Osmotic Concentration

    NASA Technical Reports Server (NTRS)

    Flynn, Michael

    2004-01-01

    Design for microgravity has traditionally not been well integrated early on into the development of advanced life support (ALS) technologies. NASA currently has a many ALS technologies that are currently being developed to high technology readiness levels but have not been formally evaluated for microgravity compatibility. Two examples of such technologies are the Vapor Phase Catalytic Ammonia Removal Technology and the Direct Osmotic Concentration Technology. This presentation will cover the design of theses two systems and will identify potential microgravity issues.

  16. Pretreatment of wastepaper and pulp mill sludge by aqueous ammonia and hydrogen peroxide.

    PubMed

    Kim, J S; Lee, Y Y; Park, S C

    2000-01-01

    Pretreatment of two different softwood-based lignocellulosic wastes (newsprint and Kraft pulp mill sludge) was investigated. Pretreatment was done by aqueous ammonia and hydrogen peroxide (H2O2), two delignifying reagents that are environmentally benign. Three different treatment schemes were employed: aqueous ammonia alone (ammonia recycled percolation [ARP]), mixed stream of aqueous ammonia and H2O2, and successive treatment with H2O2 and aqueous ammonia. In all cases there was a substantial degree of delignification ranging from 30 to 50%. About half of the hemicellulose sugars were dissolved into the process effluent. Retention of cellulose after pretreatment varied from 85 to 100% for newspaper feedstock and from 77 to 85% for the pulp mill sludge. After treatment with aqueous ammonia alone (ARP), the digestibility of newspaper and the pulp mill sludge was improved only by 5% (from 40 to 45% for the former and from 68 to 73% for the latter), despite a substantial degree of delignification occurring after the ARP process. The lignin content thus did not correlate with the digestibility for these substrates. Simultaneous treatment with H2O2 and aqueous ammonia did not bring about any significant improvement in the digestibility over that of the ARP. A successive treatment by H2O2 and ARP showed the most promise because it improved the digestibility of the newspaper from 41 to 75%, a level comparable to that of alpha-cellulose. PMID:10849784

  17. Substrate Dependency and Effect of Xylanase Supplementation on Enzymatic Hydrolysis of Ammonia-Treated Biomass

    NASA Astrophysics Data System (ADS)

    Gupta, Rajesh; Kim, Tae Hyun; Lee, Yoon Y.

    Pretreatment based on aqueous ammonia was investigated under two different modes of operation: soaking in aqueous ammonia and ammonia recycle percolation. These processes were applied to three different feedstocks with varied composition: corn stover, high lignin (HL), and low lignin (LL) hybrid poplars. One of the important features of ammonia-based pretreatment is that most of the hemicellulose is retained after treatment, which simplifies the overall bioconversion process and enhances the conversion efficiency. The pretreatment processes were optimized for these feedstocks, taking carbohydrate retention as well as sugar yield in consideration. The data indicate that hybrid poplar is more difficult to treat than corn stover, thus, requires more severe conditions. On the other hand, hybrid poplar has a beneficial property that it retains most of the hemicellulose after pretreatment. To enhance the digestibility of ammonia-treated poplars, xylanase was supplemented during enzymatic hydrolysis. Because of high retention of hemicellulose in treated hybrid poplar, xylanase supplementation significantly improved xylan as well as glucan digestibility. Of the three feedstocks, best results and highest improvement by xylanase addition was observed with LL hybrid poplar, showing 90% of overall sugar yield.

  18. Percolation Hamiltonians

    Microsoft Academic Search

    Peter Müller; Peter Stollmann

    2010-01-01

    \\u000a There has been quite some activity and progress concerning spectral asymptotics of random operators that are defined on percolation\\u000a subgraphs of different types of graphs. In this short survey we record some of these results and explain the necessary background\\u000a coming from different areas in mathematics: graph theory, group theory, probability theory and random operators.

  19. Ammonia Process by Pressure Swing Adsorption

    SciTech Connect

    Dr Felix Jegede

    2010-12-27

    The overall objective of the project is to design, develop and demonstrate a technically feasible and commercially viable system to produce ammonia along with recovery of the products by adsorption separation methods and significantly decrease the energy requirement in ammonia production. This is achieved through a significantly more efficient ammonia psa recovery system. The new ammonia recovery system receives the reactor effluents and achieves complete ammonia recovery, (which completely eliminates the energy intensive refrigeration and condensation system currently used in ammonia production). It also recovers the unused reactants and recycles them back to the reactor, free of potential reactor contaminants, and without the need for re-compression and re-heat of recycle stream thereby further saving more energy. The result is a significantly lower energy consumption, along with capital cost savings.

  20. Conformal Invariance in Percolation

    E-print Network

    Narasayya, Vivek

    problem in percolation is whether there is an infinite percolation component at p = p c on Z d . Kesten c is unknown in most interesting cases. An exception is Z 2 . In a celebrated theorem, Kesten has

  1. Liquid Ammonia

    Microsoft Academic Search

    J. J. Lagowski

    2007-01-01

    This is a review of the use of liquid ammonia as a solvent for chemical processes. Among the subjects covered are the physical properties of the solvent that defines it as “water like.” The physical and chemical processes associated with the formation of solutions and the properties of those solutions are also convered. Included is a discussion of metal?ammonia solutions,

  2. Ammonia Test

    MedlinePLUS

    ... ammonia are relatively common in newborns, where the level may rise and fall without causing detectible symptoms. An increased ... Back to top 2. When my increased ammonia level has returned to normal, can it rise again? It depends on why it was increased ...

  3. Threshold of hierarchical percolating systems.

    PubMed

    Li, Jiantong; Ray, Biswajit; Alam, Muhammad A; Östling, Mikael

    2012-02-01

    Many modern nanostructured materials and doped polymers are morphologically too complex to be interpreted by classical percolation theory. Here, we develop the concept of a hierarchical percolating (percolation-within-percolation) system to describe such complex materials and illustrate how to generalize the conventional percolation to double-level percolation. Based on Monte Carlo simulations, we find that the double-level percolation threshold is close to, but definitely larger than, the product of the local percolation thresholds for the two enclosed single-level systems. The deviation may offer alternative insights into physics concerning infinite clusters and open up new research directions for percolation theory. PMID:22463155

  4. Ammonia (GCMP)

    NSDL National Science Digital Library

    Ammonia fountain: this is a resource in the collection "General Chemistry Multimedia Problems". In an ammonia fountain, a flask is filled with ammonia gas. A tube from the flask extends into a pan of water that contains phenolphthalein. When a rubber bulb full of water is squeezed, the water squirts into the flask. Water from the pan then is pushed into the flask and the indicator changes color. General Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.

  5. Percolation? Harry Kesten

    E-print Network

    Marcolli, Matilde

    Percolation? Harry Kesten 572 NOTICES OF THE AMS VOLUME 53, NUMBER 5 Percolation is a simple, but all edges are assumed open. This version is called ?W H A T I S . . . Harry Kesten is emeritus professor of mathematics at Cor- nell University. His e-mail address is kesten@math. cornell.edu. #12;MAY

  6. Percolation on sparse networks.

    PubMed

    Karrer, Brian; Newman, M E J; Zdeborová, Lenka

    2014-11-14

    We study percolation on networks, which is used as a model of the resilience of networked systems such as the Internet to attack or failure and as a simple model of the spread of disease over human contact networks. We reformulate percolation as a message passing process and demonstrate how the resulting equations can be used to calculate, among other things, the size of the percolating cluster and the average cluster size. The calculations are exact for sparse networks when the number of short loops in the network is small, but even on networks with many short loops we find them to be highly accurate when compared with direct numerical simulations. By considering the fixed points of the message passing process, we also show that the percolation threshold on a network with few loops is given by the inverse of the leading eigenvalue of the so-called nonbacktracking matrix. PMID:25432059

  7. Percolation on Sparse Networks

    NASA Astrophysics Data System (ADS)

    Karrer, Brian; Newman, M. E. J.; Zdeborová, Lenka

    2014-11-01

    We study percolation on networks, which is used as a model of the resilience of networked systems such as the Internet to attack or failure and as a simple model of the spread of disease over human contact networks. We reformulate percolation as a message passing process and demonstrate how the resulting equations can be used to calculate, among other things, the size of the percolating cluster and the average cluster size. The calculations are exact for sparse networks when the number of short loops in the network is small, but even on networks with many short loops we find them to be highly accurate when compared with direct numerical simulations. By considering the fixed points of the message passing process, we also show that the percolation threshold on a network with few loops is given by the inverse of the leading eigenvalue of the so-called nonbacktracking matrix.

  8. Social percolation models

    NASA Astrophysics Data System (ADS)

    Solomon, Sorin; Weisbuch, Gerard; de Arcangelis, Lucilla; Jan, Naeem; Stauffer, Dietrich

    2000-03-01

    We here relate the occurrence of extreme market shares, close to either 0 or 100%, in the media industry to a percolation phenomenon across the social network of customers. We further discuss the possibility of observing self-organized criticality when customers and cinema producers adjust their preferences and the quality of the produced films according to previous experience. Comprehensive computer simulations on square lattices do indeed exhibit self-organized criticality towards the usual percolation threshold and related scaling behaviour.

  9. Percolation with Constant Freezing

    NASA Astrophysics Data System (ADS)

    Mottram, Edward

    2014-06-01

    We introduce and study a model of percolation with constant freezing ( PCF) where edges open at constant rate , and clusters freeze at rate independently of their size. Our main result is that the infinite volume process can be constructed on any amenable vertex transitive graph. This is in sharp contrast to models of percolation with freezing previously introduced, where the limit is known not to exist. Our interest is in the study of the percolative properties of the final configuration as a function of . We also obtain more precise results in the case of trees. Surprisingly the algebraic exponent for the cluster size depends on the degree, suggesting that there is no lower critical dimension for the model. Moreover, even for , it is shown that finite clusters have algebraic tail decay, which is a signature of self organised criticality. Partial results are obtained on , and many open questions are discussed.

  10. Hanford recycling

    SciTech Connect

    Leonard, I.M.

    1996-09-01

    This paper is a study of the past and present recycling efforts on the Hanford site and options for future improvements in the recycling program. Until 1996, recycling goals were voluntarily set by the waste generators: this year, DOE has imposed goals for all its sites to accomplish by 1999. Hanford is presently meeting the voluntary site goals, but may not be able to meet all the new DOE goals without changes to the program. Most of these new DOE goals are recycling goals: * Reduce the generation of radioactive (low-level) waste from routine operations 50 percent through source reduction and recycling. * Reduce the generation of low-level mixed waste from routine operations 50 percent through source reduction and recycling. * Reduce the generation of hazardous waste from routine operations 50 percent through source reduction and recycling. * Recycle 33 percent of the sanitary waste from all operations. * Increase affirmative procurement of EPA-designated recycled items to 100 percent. The Hanford recycling program has made great strides-there has been a 98 percent increase in the amount of paper recycled since its inception in 1990. Hanford recycles paper, chemicals cardboard, tires, oil, batteries, rags, lead weights, fluorescent tubes, aerosol products, concrete, office furniture, computer software, drums, toner cartridges, and scrap metal. Many other items are recycled or reused by individual groups on a one time basis without a formal contract. Several contracts are closed-loop contracts which involve all parts of the recycle loop. Considerable savings are generated from recycling, and much more is possible with increased attention and improvements to this program. General methods for improving the recycling program to ensure that the new goals can be met are: a Contract and financial changes 0 Tracking database and methods improvements 0 Expanded recycling efforts. Specifically, the Hanford recycling program would be improved by: 0 Establishing one overall DOE recycling contract at the Hanford site and a central group to control the contract. 0 Using a BOA or MTS contract as a way to get proceeds from recycling back to site facilities to provide incentives for recycling. . Upgrading tracking mechanisms to track and recycle construction waste which is presently buried in onsite pits. . Establishing contract performance measures which hold each project accountable for specific waste reduction goals. * Recycling and reusing any material or equipment possible as buildings are dismantled.

  11. Hanford recycling

    Microsoft Academic Search

    1996-01-01

    This paper is a study of the past and present recycling efforts on the Hanford site and options for future improvements in the recycling program. Until 1996, recycling goals were voluntarily set by the waste generators: this year, DOE has imposed goals for all its sites to accomplish by 1999. Hanford is presently meeting the voluntary site goals, but may

  12. RECYCLING TODAY

    NSDL National Science Digital Library

    Miss Smith

    2010-12-03

    We have probably heard of recycling but what is it really and why is it so improtant to do? Please answer the questions below as well as visiting the different websites to explore what recycling really is. Form groups of 4 and explore the following websites as well as answer the questions which follow. The first website is of Recycle City where you will be exploring the City and how they recycle. Recyle City Why Recycling is Important Now please answer the following questions on paper. 1. What are the 3 R's? Explain in further ...

  13. Electrical Percolation Based Biosensors

    PubMed Central

    Bruck, Hugh Alan; Yang, Minghui; Kostov, Yordan; Rasooly, Avraham

    2013-01-01

    A new approach to label free biosensing has been developed based on the principle of “electrical percolation”. In electrical percolation, long-range electrical connectivity is formed in randomly oriented and distributed systems of discrete elements. By applying this principle to biological interactions, it is possible to measure biological components both directly and electronically. The main element for electrical percolation biosensor is the biological semiconductor (BSC) which is a multi-layer 3-D carbon nanotube-antibody network. In the BSC, molecular interactions, such as binding of antigens to the antibodies, disrupt the network continuity causing increased resistance of the network. BSCs can be fabricated by immobilizing conducting elements, such as pre-functionalized single-walled carbon nanotubes (SWNTs)-antibody complex, directly onto a substrate, such as a Poly(methyl methacrylate) (PMMA) surface (also known as plexi-glass or Acrylic). BSCs have been demonstrated for direct (label-free) electronic measurements of antibody-antigen binding using SWNTs. If the concentration of the SWNT network is slightly above the electrical percolation threshold, then binding of a specific antigen to the pre-functionalized SWNT dramatically increases the electrical resistance due to changes in the tunneling between the SWNTs. Using anti-Staphylococcal enterotoxin B (SEB) IgG as a “gate” and SEB as an “actuator”, it was demonstrated that the BSC was able to detect SEB at concentrations of 1 ng/ml. Based on this concept, an automated configuration for BSCs is described here that enables real time continuous detection. The new BSC configuration may permit assembly of multiple sensors on the same chip to create “Biological Central Processing Units (CPUs)” with multiple biological elements, capable of processing and sorting out information on multiple analytes simultaneously. PMID:24041756

  14. Forest Fires and Percolation

    NSDL National Science Digital Library

    McGath, Gary

    This is the description and instructions as well as a link for the "Forest Fires and Percolation" applet. It builds a background with a "hands-on" activity for the students which then leads to the applet itself. The applet is a game where the object is to save as many trees from the forest fire as possible. It shows the spread of a fire with the variable of density and the probability of the number of surviving trees.

  15. Percolation testing and hydraulic conductivity of soils for percolation areas.

    PubMed

    Mulqueen, J; Rodgers, M

    2001-11-01

    The results of specific percolation tests are expressed in terms of field saturated hydraulic conductivity (Kfs) of the soil. The specific tests comprise the Irish SR 6 and the UK BS 6297 standard tests and the inversed auger hole and square hole tests employed for the design of land drainage. Percolation times from these tests are converted to Kfs values using unit gradient theory and the Elrick and Reynolds (Soil Sci. 142(5) (1986) 308) model which takes into account gravitational, pressure head and matric potential gradients. Kfs is then expressed as the inverse of the percolation rate times a constant, in this way the percolation rate can be directly related to Kfs of the soil. A plot of Kfs against percolation rate for the Irish SR 6 and the UK BS 6297 standard tests is asymptotic at Kfs values less than 0.2 m/d and greater than 0.8 m/d. This behaviour creates difficulty in setting limits for percolation rates in standards. Curves are provided which enable Kfs values to be read off from percolation tests without the restrictions of head range currently enforced, for example in the Irish SR 6 and BS 6297 standards. Experimental measurements of percolation rates and Kfs were carried out on two sands in the laboratory and in the field on two soils. Kfs of these four materials was also measured using a tension infiltrometer and the Guelph permeameter. The saturated hydraulic conductivities (Ks) of the sands were also estimated in a falling head laboratory apparatus and by the Hazen formula. There was good agreement between the different tests for Kfs on each material. Because percolation time continued to increase significantly in consecutive tests in the same test hole while Kfs became constant, the latter is a better measure of the suitability of soils for percolation. PMID:12230173

  16. Scaling theory of percolation clusters

    Microsoft Academic Search

    D. Stauffer

    1979-01-01

    For beginners: This review tries to explain percolation through the cluster properties; it can also be used as an introduction to critical phenomena at other phase transitions for readers not familiar with scaling theory. In percolation each site of a periodic lattice is randomly occupied with probability p or empty with probability 1-p. An s-cluster is a group of s

  17. Analysis of instability in an industrial ammonia John C. Morud Sigurd Skogestad

    E-print Network

    Skogestad, Sigurd

    of the instability is the positive feedback from the heat recycle caused by the feed-e uent heat exchanger. We rstAnalysis of instability in an industrial ammonia reactor John C. Morud Sigurd Skogestad Chemical was an incident in an industrial plant, where the ammonia synthesis reactor became unstable with rapid temperature

  18. Percolation and Gelation

    NASA Astrophysics Data System (ADS)

    Daoud, Mohamed

    2008-03-01

    The sol-Gel transition, as well as the vulcanization of Polymers chains, was described long ago by Flory, Stockmayer, Zimm within mean field approximation. This however had strong limitations because both excluded volume interactions and loops were neglected. An important progress was made when an analogy between percolation and gelation was made by de Gennes and Stauffer. We will discuss some recent experiments showing the relevance of percolation in the description of the sol-gel transition, as well as another important concept also introduced by de Gennes concerning the possibility of observation of classical exponents in the case of vulcanization. We will also consider briefly the influence of diffusion on aggregation properties. Our understanding of dynamical properties close to the sol-gel transition is lower than that of the static ones. Some analogies were given by de Gennes to describe various hydrodynamic limits, but the experimental results still lead to some discussions. Finally, we will mention some generalizations and open questions.

  19. Weak percolation on multiplex networks

    NASA Astrophysics Data System (ADS)

    Baxter, Gareth J.; Dorogovtsev, Sergey N.; Mendes, José F. F.; Cellai, Davide

    2014-04-01

    Bootstrap percolation is a simple but nontrivial model. It has applications in many areas of science and has been explored on random networks for several decades. In single-layer (simplex) networks, it has been recently observed that bootstrap percolation, which is defined as an incremental process, can be seen as the opposite of pruning percolation, where nodes are removed according to a connectivity rule. Here we propose models of both bootstrap and pruning percolation for multiplex networks. We collectively refer to these two models with the concept of "weak" percolation, to distinguish them from the somewhat classical concept of ordinary ("strong") percolation. While the two models coincide in simplex networks, we show that they decouple when considering multiplexes, giving rise to a wealth of critical phenomena. Our bootstrap model constitutes the simplest example of a contagion process on a multiplex network and has potential applications in critical infrastructure recovery and information security. Moreover, we show that our pruning percolation model may provide a way to diagnose missing layers in a multiplex network. Finally, our analytical approach allows us to calculate critical behavior and characterize critical clusters.

  20. Ideas: Recycling.

    ERIC Educational Resources Information Center

    Chessin, Debby A.; And Others

    1994-01-01

    Presents classroom ideas focusing on connections among mathematics, concern for the environment, and conservation of natural resources, including decomposition, water conservation, packaging materials, use of manufactured cans, and recycling. Includes reproducible student worksheets. (MKR)

  1. Extreme Recycling

    E-print Network

    Hacker, Randi

    2009-01-14

    Broadcast Transcript: Singing the recycling blues because you have to separate your chipboard from your newspaper, your steel from your aluminum, your #1 from your #2 plastic? Pantywaists! The residents of Kamikatsu, Japan ...

  2. Recycle City

    NSDL National Science Digital Library

    Recycling made fun. The Environmental Protection Agency's Recycle City Web site offers students an interactive way to learn how recycling can affect their environment. Users can click any part of the cartoon drawing of the city to learn about that particular building or site and what can be done to decrease waste. The site also contains a more involved exercise called the Dumptown game, where visitors click on City Hall to view various recycling programs and choose the program(s) the city will implement. Once implemented, that activity can be seen taking place in Dumptown. Although the Dumptown exercise may require the help of a teacher to navigate for younger students, both exercises are excellent for K-12 teachers and students.

  3. Continuum percolation of polydisperse nanofillers.

    PubMed

    Otten, Ronald H J; van der Schoot, Paul

    2009-11-27

    We show that a generalized connectedness percolation theory can be made tractable for a large class of anisotropic particle mixtures that potentially contain an infinite number of components. By applying our methodology to carbon-nanotube composites, we explain the huge variations found in the onset of electrical conduction in terms of a percolation threshold that turns out to be sensitive to polydispersity in particle length and diameter. The theory also allows us to model the influence of the presence of nonconductive species in the mixture, such as is the case for single-walled nanotubes, showing that these raise the percolation threshold proportionally to their abundance. PMID:20366111

  4. Percolation and galaxies.

    PubMed

    Schulman, L S; Seiden, P E

    1986-07-25

    A theory is presented in which much of the structure of spiral galaxies arises from a percolation phase transition that underlies the phenomenon of propagating star formation. According to this view, the appearance of spiral arms is a consequence of the differential rotation of the galaxy and the characteristic divergence of correlation lengths for continuous phase transitions. Other structural properties of spiral galaxies, such as the distribution of the gaseous components and the luminosity, arise directly from a feedback mechanism that pins the star formation rate close to the critical point of the phase transition. The approach taken in this article differs from traditional dynamical views. The argument is presented that, at least for some galaxies, morphological and other features are already fixed by general properties of phase transitions, irrespective of detailed dynamic or other considerations. PMID:17794566

  5. Nonlinear Percolation Conductivity.

    NASA Astrophysics Data System (ADS)

    Kenkel, Stephen William

    The percolation conductivity problem is generalized to consider a system in which the conducting bonds are nonlinear conductors. It is found that a new universality class is formed by those conductors which are power law devices with an I-V characteristic V = (VBAR)I(VBAR)('(alpha))R. The problem is studied by means of a model due to Skal, Shklovskii, and De Gennes (SSDG). Renormalization group is applied in two dimensions, and the problem is solved on the Cayley tree, a model which applies above the upper critical dimensionality. The SSDG model is found capable of explaining most of the results and gives the conductivity exponent t as. t = (d - 1)(nu) + ( \\- (nu))/(alpha). where (nu) is the correlation length exponent, and the effective length exponent is only weakly dependent on dimensionality and the nonlinearity parameter (alpha).

  6. Watersheds and Explosive percolation

    NASA Astrophysics Data System (ADS)

    Herrmann, Hans J.; Araujo, Nuno A. M.

    The recent work by Achlioptas, D'Souza, and Spencer opened up the possibility of obtaining a discontinuous (explosive) percolation transition by changing the stochastic rule of bond occupation. Despite the active research on this subject, several questions still remain open about the leading mechanism and the properties of the system. We review the largest cluster and the Gaussian models recently introduced. We show that, to obtain a discontinuous transition it is solely necessary to control the size of the largest cluster, suppressing the growth of a cluster di_ering significantly, in size, from the average one. As expected for a discontinuous transition, a Gaussian cluster-size distribution and compact clusters are obtained. The surface of the clusters is fractal, with the same fractal dimension of the watershed line.

  7. Toxicity of ammonia in pore-water and in the water column to freshwater benthic invertebrates

    SciTech Connect

    Whiteman, F.W.; Kahl, M.D.; Rau, D.M.; Balcer, M.D. [Univ. of Wisconsin, Superior, WI (United States). Lake Superior Research Inst.; Ankley, G.T. [Environmental Protection Agency, Duluth, MN (United States)

    1994-12-31

    Ammonia has been mentioned as both a primary toxicant and a factor that can produce false positive results in laboratory sediment tests using benthic invertebrates. This study developed a sediment dosing system that percolates an ammonia solution through sediment to achieve target porewater ammonia concentrations that remain stable over four and ten day spiked sediment tests. Ten day flow-through water-only tests and ten day spiked sediment tests were used to determine the toxicity of ammonia in the water column and in the sediment pore-water to the oligochaete Lumbriculus variegatus and the midge Chironomus tentans. Four-day tests were run with the amphipod Hyalella azteca. The relationship between water column ammonia toxicity and sediment pore-water ammonia toxicity is influenced by the organism`s association with the sediment. For Lumbriculus variegatus and Chironomus tentans that burrow into the sediment and are in direct contact with the porewater, the pore-water LC50 for ammonia is 30--40% higher than the water-only LC50 for each species. Hyalella azteca is epibenthic and avoids ammonia spiked sediment, thus ammonia in the water column is considerably more toxic than the pore-water ammonia with the porewater LC50 about 800% higher than the water only LC50.

  8. Predicting percolation thresholds in networks

    NASA Astrophysics Data System (ADS)

    Radicchi, Filippo

    2015-01-01

    We consider different methods, which do not rely on numerical simulations of the percolation process, to approximate percolation thresholds in networks. We perform a systematic analysis on synthetic graphs and a collection of 109 real networks to quantify their effectiveness and reliability as prediction tools. Our study reveals that the inverse of the largest eigenvalue of the nonbacktracking matrix of the graph often provides a tight lower bound for true percolation threshold. However, in more than 40 % of the cases, this indicator is less predictive than the naive expectation value based solely on the moments of the degree distribution. We find that the performance of all indicators becomes worse as the value of the true percolation threshold grows. Thus, none of them represents a good proxy for the robustness of extremely fragile networks.

  9. Invasion percolation between two sites.

    PubMed

    Araújo, A D; Vasconcelos, T F; Moreira, A A; Lucena, L S; Andrade, J S

    2005-10-01

    We investigate the process of invasion percolation between two sites (injection and extraction sites) separated by a distance r in two-dimensional lattices of size L. Our results for the nontrapping invasion percolation model indicate that the statistics of the mass of invaded clusters is significantly dependent on the local occupation probability (pressure) Pe at the extraction site. For Pe = 0, we show that the mass distribution of invaded clusters P(M) follows a power-law P(M) approximately M(-alpha) for intermediate values of the mass M, with an exponent alpha = 1.39+/-0.03. When the local pressure is set to Pe = Pc, where Pc corresponds to the site percolation threshold of the lattice topology, the distribution P(M) still displays a scaling region, but with an exponent alpha = 1.02+/-0.03. This last behavior is consistent with previous results for the cluster statistics in standard percolation. In spite of these differences, the results of our simulations indicate that the fractal dimension of the invaded cluster does not depend significantly on the local pressure Pe and it is consistent with the fractal dimension values reported for standard invasion percolation. Finally, we perform extensive numerical simulations to determine the effect of the lattice borders on the statistics of the invaded clusters and also to characterize the self-organized critical behavior of the invasion percolation process. PMID:16383378

  10. Constraint percolation on hyperbolic lattices

    NASA Astrophysics Data System (ADS)

    Lopez, Jorge; Schwarz, J. M.

    2012-02-01

    Constraint percolation models include constraints on the occupation of sites to, for example, better understand the onset of glassiness in glass-forming liquids. The dynamical glass transition in the Fredrickson-Andersen model simplifies to the study of the percolation transition in k-core percolation where every occupied site must have at least k occupied neighbors. Other constraint percolation models, such as force-balance percolation, have been introduced to begin to account for mechanical equilibrium on each particle arising during the onset of jamming. To study a mean-field-like version of force-balance percolation in which the directionality of forces becomes important, we consider clusters with occupied particles satisfying the k=3-core condition and lying inside a triangle determined by three of its occupied neighbors. The model is constructed on a tessellation of the Poincar'e disk, thus, bearing a hyperbolic structure. Models on such spaces exhibit mean-field-like behavior and also play an important role in generating geometric frustration in glassy systems. We analytically investigate the conditions under which there exists a transition as well as the underlying nature of the transition. We also present numerical results to compare with our analytical results.

  11. Textile recycling

    SciTech Connect

    Jablonowski, E. (Killam Associates, Millburn, NJ (United States)); Carlton, J.

    1995-01-01

    The most common household textiles include clothing, linens, draperies, carpets, shoes, handbags, and rugs. Old clothing, of course, is the most readily reused and/or recycled residentially generated textile category. State and/or local mandates to recycle a percentage of the waste stream are providing the impetus to add new materials to existing collection programs. Concurrently, the textile industry is aggressively trying to increase its throughput by seeking new sources of material to meet increased world demand for product. As experienced with drop-off programs for traditional materials, a majority of residents will not recycle materials unless the collection programs are convenient, i.e., curbside collection. The tonnage of marketable textiles currently being landfilled provide evidence of this. It is the authors' contention that if textile recycling is made convenient and accessible to every household in a municipality or region, then the waste stream disposed may be reduced in a similar fashion as when traditional recyclables are included in curbside programs.

  12. Tire Recycling

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Cryopolymers, Inc. tapped NASA expertise to improve a process for recycling vehicle tires by converting shredded rubber into products that can be used in asphalt road beds, new tires, hoses, and other products. In conjunction with the Southern Technology Applications Center and Stennis Space Center, NASA expertise in cryogenic fuel-handling needed for launch vehicle and spacecraft operations was called upon to improve the recycling concept. Stennis advised Cryopolymers on the type of equipment required, as well as steps to reduce the amount of liquid nitrogen used in the process. They also guided the company to use more efficient ways to control system hardware. It is estimated that more than 300 million tires nationwide are produced per year. Cryopolymers expects to reach a production rate of 5,000 tires recycled per day.

  13. Assessing Ammonia Treatment Options

    EPA Science Inventory

    This is the second of three articles to help water system operators understand ammonia and how to monitor and control its effects at the plant and in the distribution system. The first article (Opflow, April 2012) provided an overview of ammonia's chemistry, origins, and water sy...

  14. Endocytic recycling

    Microsoft Academic Search

    Frederick R. Maxfield; Timothy E. McGraw

    2004-01-01

    After endocytosis, most membrane proteins and lipids return to the cell surface, but some membrane components are delivered to late endosomes or the Golgi. We now understand that the pathways taken by internalized molecules that eventually recycle to the cell surface can be surprisingly complex and can involve a series of sorting events that occur in several organelles. The molecular

  15. Invasion percolation on regular trees

    E-print Network

    Omer Angel; Jesse Goodman; Frank den Hollander; Gordon Slade

    2008-04-21

    We consider invasion percolation on a rooted regular tree. For the infinite cluster invaded from the root, we identify the scaling behavior of its $r$-point function for any $r\\geq2$ and of its volume both at a given height and below a given height. We find that while the power laws of the scaling are the same as for the incipient infinite cluster for ordinary percolation, the scaling functions differ. Thus, somewhat surprisingly, the two clusters behave differently; in fact, we prove that their laws are mutually singular. In addition, we derive scaling estimates for simple random walk on the cluster starting from the root. We show that the invasion percolation cluster is stochastically dominated by the incipient infinite cluster. Far above the root, the two clusters have the same law locally, but not globally. A key ingredient in the proofs is an analysis of the forward maximal weights along the backbone of the invasion percolation cluster. These weights decay toward the critical value for ordinary percolation, but only slowly, and this slow decay causes the scaling behavior to differ from that of the incipient infinite cluster.

  16. Molecular Structure of Ammonia

    NSDL National Science Digital Library

    2006-05-02

    Ammonia is a non-ionic colorless gas at ambient temperatures and a hydrogen bonding liquid at 240 Kelvin that has the remarkable ability to dissolve alkali metals. Ammonia is a Lewis base and is readily absorbed by water to form small amounts of ammonium hydroxide (pKb = 4.74). Naturally, ammonia has its sources in the biosphere (the nitrogen cycle) and is a trace gas in air and a source of ammonium ions in rain and atmospheric aerosols. Ammonia is prepared industrially by the Haber-Bosch process in quantities exceeding 120 million metric tons per year. In this process, ammonia gas is formed when hydrogen and nitrogen (3:1) are compressed to pressures of 200 atm and passed over an iron catalyst at 380-450 degrees C. Much of the ammonia produced this way (85%) is used as fertilizers on crops, a significant portion of which leaches from croplands into streams causing nitrate pollution and eutrophication of waterways (e.g., dead-zone in the Gulf of Mexico). Other sources of ammonia include combustion (coal and biomass burning) and from bacterial decomposition of animal excreta.

  17. Ammonia Leak Locator Study

    NASA Technical Reports Server (NTRS)

    Dodge, Franklin T.; Wuest, Martin P.; Deffenbaugh, Danny M.

    1995-01-01

    The thermal control system of International Space Station Alpha will use liquid ammonia as the heat exchange fluid. It is expected that small leaks (of the order perhaps of one pound of ammonia per day) may develop in the lines transporting the ammonia to the various facilities as well as in the heat exchange equipment. Such leaks must be detected and located before the supply of ammonia becomes critically low. For that reason, NASA-JSC has a program underway to evaluate instruments that can detect and locate ultra-small concentrations of ammonia in a high vacuum environment. To be useful, the instrument must be portable and small enough that an astronaut can easily handle it during extravehicular activity. An additional complication in the design of the instrument is that the environment immediately surrounding ISSA will contain small concentrations of many other gases from venting of onboard experiments as well as from other kinds of leaks. These other vapors include water, cabin air, CO2, CO, argon, N2, and ethylene glycol. Altogether, this local environment might have a pressure of the order of 10(exp -7) to 10(exp -6) torr. Southwest Research Institute (SwRI) was contracted by NASA-JSC to provide support to NASA-JSC and its prime contractors in evaluating ammonia-location instruments and to make a preliminary trade study of the advantages and limitations of potential instruments. The present effort builds upon an earlier SwRI study to evaluate ammonia leak detection instruments [Jolly and Deffenbaugh]. The objectives of the present effort include: (1) Estimate the characteristics of representative ammonia leaks; (2) Evaluate the baseline instrument in the light of the estimated ammonia leak characteristics; (3) Propose alternative instrument concepts; and (4) Conduct a trade study of the proposed alternative concepts and recommend promising instruments. The baseline leak-location instrument selected by NASA-JSC was an ion gauge.

  18. SOURCE ASSESSMENT: SYNTHETIC AMMONIA PRODUCTION

    EPA Science Inventory

    The report describes a study of air emissions from the production of synthetic ammonia. In 1976, 90 synthetic ammonia plants in 30 states produced 15.2 million metric tons of anhydrous ammonia. Ammonia is synthesized by the reaction of nitrogen and hydrogen. Most plants produce h...

  19. Spectral analysis on explosive percolation

    NASA Astrophysics Data System (ADS)

    Chung, N. N.; Chew, L. Y.; Lai, C. H.

    2013-03-01

    We study the spectral properties of the process of explosive percolation. In particular, we explore how the maximum eigenvalue of the adjacency matrix of a network which governs the spreading efficiency evolves as the density of connection increases. Interestingly, for networks with connectivity that grow in an explosive way, information spreading and mass transport are found to be carried out inefficiently. In the conventional explosive percolation models that we studied, the sudden emergences of large-scale connectivity are found to come with relatively lowered efficiency of spreading. Nevertheless, the spreading efficiency of the explosive model can be increased by introducing heterogeneous structures into the networks.

  20. Precipitation Recycling

    NASA Technical Reports Server (NTRS)

    Eltahir, Elfatih A. B.; Bras, Rafael L.

    1996-01-01

    The water cycle regulates and reflects natural variability in climate at the regional and global scales. Large-scale human activities that involve changes in land cover, such as tropical deforestation, are likely to modify climate through changes in the water cycle. In order to understand, and hopefully be able to predict, the extent of these potential global and regional changes, we need first to understand how the water cycle works. In the past, most of the research in hydrology focused on the land branch of the water cycle, with little attention given to the atmospheric branch. The study of precipitation recycling which is defined as the contribution of local evaporation to local precipitation, aims at understanding hydrologic processes in the atmospheric branch of the water cycle. Simply stated, any study on precipitation recycling is about how the atmospheric branch of the water cycle works, namely, what happens to water vapor molecules after they evaporate from the surface, and where will they precipitate?

  1. Computer Recycling

    NSDL National Science Digital Library

    Given current rates of computer consumerism and technological advances, one might expect to find a lot of computers out there in the world. What happens to these old computers? This Topic in Depth explores this issue, reviews some options for recycling computers, and provides tips for anyone considering purchasing a refurbished computer. The first article from BBC News (1) reports on research which suggests that "the number of personal computers worldwide is expected to double by 2010 to 1.3 billion machines." The second article from Oasis, a project of the Irish eGovernment initiative, (2) reviews some of the issues surrounding waste from electrical and electronic equipment. This next article from PC World (3) gives some ideas for how to dispose of an old notebook computer. One option, of course, is to donate your notebook, which is discussed in this article from Tech Soup (4). Another resource for information on computer recycling and reuse is this website from CompuMentor (5). Given the current market for computers, many are considering refurbished computers. This article from Vnunet (6 ) explains what a refurbished computer is while the next website provides some tips for buying a refurbished computer (7 ). Finally, this article from About.com reports on the recently introduced National Computer Recycling Act (8).

  2. Ammonia Release on ISS

    NASA Technical Reports Server (NTRS)

    Macatangay, Ariel

    2009-01-01

    Crew: Approximately 53% metabolic load Product of protein metabolism Limit production of ammonia by external regulation NOT possbile Payloads Potential source Scientific experiments Thorough safety review ensures sufficient levels of containment

  3. Ammonia Clouds on Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Click on the image for movie of Ammonia Ice Clouds on Jupiter

    In this movie, put together from false-color images taken by the New Horizons Ralph instrument as the spacecraft flew past Jupiter in early 2007, show ammonia clouds (appearing as bright blue areas) as they form and disperse over five successive Jupiter 'days.' Scientists noted how the larger cloud travels along with a small, local deep hole.

  4. Explosive Percolation Transition is Actually Continuous

    NASA Astrophysics Data System (ADS)

    da Costa, R. A.; Dorogovtsev, S. N.; Goltsev, A. V.; Mendes, J. F. F.

    2010-12-01

    Recently a discontinuous percolation transition was reported in a new “explosive percolation” problem for irreversible systems [D. Achlioptas, R. M. D’Souza, and J. Spencer, Science 323, 1453 (2009)SCIEAS0036-807510.1126/science.1167782] in striking contrast to ordinary percolation. We consider a representative model which shows that the explosive percolation transition is actually a continuous, second order phase transition though with a uniquely small critical exponent of the percolation cluster size. We describe the unusual scaling properties of this transition and find its critical exponents and dimensions.

  5. Combustion Byproducts Recycling Consortium

    SciTech Connect

    Paul Ziemkiewicz; Tamara Vandivort; Debra Pflughoeft-Hassett; Y. Paul Chugh; James Hower

    2008-08-31

    Each year, over 100 million tons of solid byproducts are produced by coal-burning electric utilities in the United States. Annual production of flue gas desulfurization (FGD) byproducts continues to increase as the result of more stringent sulfur emission restrictions. In addition, stricter limits on NOx emissions mandated by the 1990 Clean Air Act have resulted in utility burner/boiler modifications that frequently yield higher carbon concentrations in fly ash, which restricts the use of the ash as a cement replacement. Controlling ammonia in ash is also of concern. If newer, 'clean coal' combustion and gasification technologies are adopted, their byproducts may also present a management challenge. The objective of the Combustion Byproducts Recycling Consortium (CBRC) is to develop and demonstrate technologies to address issues related to the recycling of byproducts associated with coal combustion processes. A goal of CBRC is that these technologies, by the year 2010, will lead to an overall ash utilization rate from the current 34% to 50% by such measures as increasing the current rate of FGD byproduct use and increasing in the number of uses considered 'allowable' under state regulations. Another issue of interest to the CBRC would be to examine the environmental impact of both byproduct utilization and disposal. No byproduct utilization technology is likely to be adopted by industry unless it is more cost-effective than landfilling. Therefore, it is extremely important that the utility industry provide guidance to the R&D program. Government agencies and private-sector organizations that may be able to utilize these materials in the conduct of their missions should also provide input. The CBRC will serve as an effective vehicle for acquiring and maintaining guidance from these diverse organizations so that the proper balance in the R&D program is achieved.

  6. Nonlocal product rules for percolation

    NASA Astrophysics Data System (ADS)

    Reis, Saulo D. S.; Moreira, André A.; Andrade, José S., Jr.

    2012-04-01

    Despite original claims of a first-order transition in the product rule model proposed by Achlioptas [ScienceSCIEAS0036-807510.1126/science.1167782 323, 1453 (2009)], recent studies indicate that this percolation model, in fact, displays a continuous transition. The distinctive scaling properties of the model at criticality, however, strongly suggest that it should belong to a different universality class than ordinary percolation. Here we introduce a generalization of the product rule that reveals the effect of nonlocality on the critical behavior of the percolation process. Precisely, pairs of unoccupied bonds are chosen according to a probability that decays as a power law of their Manhattan distance, and only that bond connecting clusters whose product of their sizes is the smallest becomes occupied. Interestingly, our results for two-dimensional lattices at criticality shows that the power-law exponent of the product rule has a significant influence on the finite-size scaling exponents for the spanning cluster, the conducting backbone, and the cutting bonds of the system. In all three cases, we observe a clear transition from ordinary to (nonlocal) explosive percolation exponents.

  7. Nonlocal product rules for percolation.

    PubMed

    Reis, Saulo D S; Moreira, André A; Andrade, José S

    2012-04-01

    Despite original claims of a first-order transition in the product rule model proposed by Achlioptas et al. [Science 323, 1453 (2009)], recent studies indicate that this percolation model, in fact, displays a continuous transition. The distinctive scaling properties of the model at criticality, however, strongly suggest that it should belong to a different universality class than ordinary percolation. Here we introduce a generalization of the product rule that reveals the effect of nonlocality on the critical behavior of the percolation process. Precisely, pairs of unoccupied bonds are chosen according to a probability that decays as a power law of their Manhattan distance, and only that bond connecting clusters whose product of their sizes is the smallest becomes occupied. Interestingly, our results for two-dimensional lattices at criticality shows that the power-law exponent of the product rule has a significant influence on the finite-size scaling exponents for the spanning cluster, the conducting backbone, and the cutting bonds of the system. In all three cases, we observe a clear transition from ordinary to (nonlocal) explosive percolation exponents. PMID:22680425

  8. Percolating the Power of Play

    Microsoft Academic Search

    Sarah Faye Cohen; Timothy Miner; Laurent Nishikawa

    2007-01-01

    At a campus that percolates the power and promise of play, the Champlain College Library asked students from our Electronic Game Design Program and the Emergent Media Center to create a game to comple- ment our Information Literacy (IL) program. Little did we know that this collaboration would lead us to question and re-envision what we mean by informa- tion

  9. Recycling Lesson Plans.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Environmental Resources, Harrisburg.

    This document contains lesson plans about recycling for teachers in grades K-12. Titles include: (1) "Waste--Where Does It Come From? Where Does It Go?" (2) "Litter Detectives," (3) "Classroom Paper Recycling," (4) "Recycling Survey," (5) "Disposal and Recycling Costs," (6) "Composting Project," (7) Used Motor Oil Recycling," (8) "Unwrapping…

  10. Green Science: Revisiting Recycling

    ERIC Educational Resources Information Center

    Palliser, Janna

    2011-01-01

    Recycling has been around for a long time--people have reused materials and refashioned them into needed items for thousands of years. More recently, war efforts encouraged conservation and reuse of materials, and in the 1970s recycling got its official start when recycling centers were created. Now, curbside recycling programs and recycling

  11. Ammonia diffusion through Nalophan™ bags.

    PubMed

    Sironi, Selena; Eusebio, Lidia; Dentoni, Licinia; Capelli, Laura; Del Rosso, Renato

    2014-01-01

    The aim of the work is to verify the diffusion rate of ammonia through the Nalophan™ film that constitutes the sampling bag, considering storage times ranging from 1 to 26 h. The ammonia decay over time was evaluated using gas-chromatography for the quantification of ammonia concentration inside the bag. The research assesses the roles of both of ammonia and water concentration gradients at the polymeric film interface on the diffusion process. The results show that both the ammonia concentration gradient and, in a less pronounced way, the water concentration gradient are the main 'engines' of ammonia diffusion. Double bags seem to represent a simple solution for preventing ammonia losses during storage. Another interesting result concerns the role of the bag surface on the ammonia diffusion rate: the higher the surface/volume (S/V) ratio, the higher the ammonia diffusion rate through the polymeric film. PMID:24552718

  12. Cooperative Secondary Authorization Recycling

    E-print Network

    Cooperative Secondary Authorization Recycling Qiang Wei, Matei Ripeanu, Konstantin Beznosov responses 2. infer approximate responses Secondary Decision Point (SDP) Secondary Authorization Recycling Cooperative Secondary Authorization Recycling SDP SDP SDP Discovery Service each SDP serves only its own PEP

  13. Percolation in real interdependent networks

    E-print Network

    Radicchi, Filippo

    2015-01-01

    The function of a real network depends not only on the reliability of its own components, but is affected also by the simultaneous operation of other real networks coupled with it. Robustness of systems composed of interdependent network layers has been extensively studied in recent years. However, the theoretical frameworks developed so far apply only to special models in the limit of infinite sizes. These methods are therefore of little help in practical contexts, given that real interconnected networks have finite size and their structures are generally not compatible with those of graph toy models. Here, we introduce a theoretical method that takes as inputs the adjacency matrices of the layers to draw the entire phase diagram for the interconnected network, without the need of actually simulating any percolation process. We demonstrate that percolation transitions in arbitrary interdependent networks can be understood by decomposing these system into uncoupled graphs: the intersection among the layers, a...

  14. String Percolation and the Glasma

    E-print Network

    J. Dias de Deus; C. Pajares

    2010-11-04

    We compare string percolation phenomenology to Glasma results on particle rapidity densities, effective string or flux tube intrinsic correlations, the ridge phenomena and long range forward-backward correlations. Effective strings may be a tool to extend the Glasma to the low density QCD regime. A good example is given by the minimum of the negative binomial distribution parameter k expected to occur at low energy/centrality.

  15. Recycling universe

    E-print Network

    Jaume Garriga; Alexander Vilenkin

    1997-07-26

    If the effective cosmological constant is non-zero, our observable universe may enter a stage of exponential expansion. In such case, regions of it may tunnel back to the false vacuum of an inflaton scalar field, and inflation with a high expansion rate may resume in those regions. An ``ideal'' eternal observer would then witness an infinite succession of cycles from false vacuum to true, and back. Within each cycle, the entire history of a hot universe would be replayed. If there were several minima of the inflaton potential, our ideal observer would visit each one of these minima with a frequency which depends on the shape of the potential. We generalize the formalism of stochastic inflation to analyze the global structure of the universe when this `recycling' process is taken into account.

  16. Percolation in dense storage arrays

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, Scott; Wilcke, Winfried W.; Garner, Robert B.; Huels, Harald

    2002-11-01

    As computers and their accessories become smaller, cheaper, and faster the providers of news, retail sales, and other services we now take for granted on the Internet have met their increasing computing needs by putting more and more computers, hard disks, power supplies, and the data communications linking them to each other and to the rest of the wired world into ever smaller spaces. This has created a new and quite interesting percolation problem. It is no longer desirable to fix computers, storage or switchgear which fail in such a dense array. Attempts to repair things are all too likely to make problems worse. The alternative approach, letting units “fail in place”, be removed from service and routed around, means that a data communications environment will evolve with an underlying regular structure but a very high density of missing pieces. Some of the properties of this kind of network can be described within the existing paradigm of site or bond percolation on lattices, but other important questions have not been explored. I will discuss 3D arrays of hundreds to thousands of storage servers (something which it is quite feasible to build in the next few years), and show that bandwidth, but not percolation fraction or shortest path lengths, is the critical factor affected by the “fail in place” disorder. Redundancy strategies traditionally employed in storage systems may have to be revised. Novel approaches to routing information among the servers have been developed to minimize the impact.

  17. Propagation strategy of ammonia fungi

    Microsoft Academic Search

    Akira Suzuki

    2009-01-01

    Ammonia fungi invade forest floors immediately after a enrichment disturbance by a large input of ammonium-nitrogen. Latent\\u000a form(s) of the ammonia fungi are spores and\\/or mycelium fragments. Ammonia fungi are characterized by their rapid germination\\u000a stimulated by the presence of ammonium-nitrogen under neutral to weakly alkaline conditions. Each ammonia fungus establishes\\u000a its territory during suppressed combative abilities of other microbes

  18. Scaling relations for 2 D percolation

    Microsoft Academic Search

    Harry Kesten

    1987-01-01

    We prove that the relations 2D-percolation hold for the usual critical exponents for 2D-percolation, provided the exponents d andv exist. Even without the last assumption various relations (inequalities) are obtained for the singular behavior near the critical point of the correlation length, the percolation probability, and the average cluster size. We show that in our models the above critical exponents

  19. Recycling Improves USA

    Microsoft Academic Search

    Luke Monroe

    Changes are occurring in recycling that will improve the United States. There are significant improvements in the economy, environment and the health of Americans due to recycling efforts. Recycling will be shown as a superior option compared to landfill, incineration and virgin material processing. Many Case studies will be discussed that show how communities are making long-term decisions for recycling.

  20. Percolation theory for nonlinear conductors

    NASA Astrophysics Data System (ADS)

    Straley, Joseph P.; Kenkel, Stephen W.

    1984-06-01

    Under broad conditions, a network of nonlinear conductors has an I-V characteristic uniquely determined by Kirchhoff's rules. By means of a renormalization calculation, we show that near the percolation threshold the details of the microscopic I-V characteristic are averaged out, so that the bulk material approaches power-law conductor behavior (V=I?). The threshold exponents t(?) and s(?) are discussed in the limiting cases of two dimensions (where they are related by duality) and high dimensionality (by solving the Cayley-tree model).

  1. Percolation-induced frost formation

    NASA Astrophysics Data System (ADS)

    Guadarrama-Cetina, J.; Mongruel, A.; González-Viñas, W.; Beysens, D.

    2013-01-01

    We report the observation of an unconventional mechanism for frost formation. On a smooth hydrophobic surface cooled much below the water freezing temperature (-9 °C), we find that, instead of the classical freezing of individual supercooled condensed droplets, frost can occur through a multi-step 2-dimensional percolation-driven mechanism. This in-plane propagation process provides a model to investigate more complex bulk phase transformations such as those occurring in atmospheric supercooled clouds. It can also lead to a new method to control and design in-plane solidification at a nanoscale level.

  2. The percolation Fourier spectrum Oded Schramm

    E-print Network

    Narasayya, Vivek

    #12;Specialize to critical percolation in planar lattices Z2 , bond percolation: 6 #12;The Harris-Kesten (Kesten 1980). pc = 1/2. 7 #12;Crossing probabilities & duality In Z2 , bond, p = 1/2 the probability on the triangular grid has a conformally invariant scaling limit. Via SLE and Kesten's work, gives the critical

  3. Recovery of ammonia nitrogen in livestock and industrial wastes using gas permeable membranes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    New waste management methods are needed that can protect the environment and allow manure management to switch back to a recycling view of manure handling. We investigated the use of gas-permeable membranes as components of new processes to capture and recover the ammonia in the liquid manures or in...

  4. Recycle Used Oil on America Recycles Day.

    ERIC Educational Resources Information Center

    White, Boyd W.

    2000-01-01

    Explains that motor oils can be reused and recycled. Educates students about environmental hazards and oil management and includes classroom activities. Addresses the National Science Education Standards. (YDS)

  5. Recycled Art: Create Puppets Using Recycled Objects.

    ERIC Educational Resources Information Center

    Clearing, 2003

    2003-01-01

    Presents an activity from "Healthy Foods from Healthy Soils" for making puppets using recycled food packaging materials. Includes background information, materials, instructions, literature links, resources, and benchmarks. (NB)

  6. Rigidity percolation on aperiodic lattices

    NASA Astrophysics Data System (ADS)

    Losev, A.; Babalievski, F.

    We studied the rigidity percolation (RP) model for two-dimensional aperiodic (quasi-crystal) lattices. The RP thresholds (for bond dilution) were obtained for several aperiodic lattices via computer simulation using the “pebble game” algorithm. It was found that the (two rhombi) Penrose lattice is always floppy in view of the RP model. The same was found for the Ammann’s octagonal lattice and the Socolar’s dodecagonal lattice. In order to impose the percolation transition we used the so-called “ferro” modification of these aperiodic tilings. We studied as well the “pinwheel” tiling which has infinitely many orientations of edges. The obtained estimates for the modified Penrose, Ammann and Socolar lattices are respectively: pcP=0.836±0.002, pcA=0.769±0.002, pcS=0.938±0.001. The bond RP threshold of the pinwheel tiling was estimated to pc=0.69±0.01. It was found that these results are very close to the Maxwell (the mean-field like) approximation for them.

  7. Fusion algebra of critical percolation

    E-print Network

    Jorgen Rasmussen; Paul A. Pearce

    2007-08-08

    We present an explicit conjecture for the chiral fusion algebra of critical percolation considering Virasoro representations with no enlarged or extended symmetry algebra. The representations we take to generate fusion are countably infinite in number. The ensuing fusion rules are quasi-rational in the sense that the fusion of a finite number of these representations decomposes into a finite direct sum of these representations. The fusion rules are commutative, associative and exhibit an sl(2) structure. They involve representations which we call Kac representations of which some are reducible yet indecomposable representations of rank 1. In particular, the identity of the fusion algebra is a reducible yet indecomposable Kac representation of rank 1. We make detailed comparisons of our fusion rules with the recent results of Eberle-Flohr and Read-Saleur. Notably, in agreement with Eberle-Flohr, we find the appearance of indecomposable representations of rank 3. Our fusion rules are supported by extensive numerical studies of an integrable lattice model of critical percolation. Details of our lattice findings and numerical results will be presented elsewhere.

  8. Atmospheric dispersion of ammonia: an ammonia fog model

    SciTech Connect

    Kansa, E.J.; Rodean, H.C.; Chan, S.T.; Ermak, D.L.

    1983-01-01

    A simplification to the two-phase ammonia vapor-droplet fog problem has been implemented to study the dispersion of a spill of 40 tons of ammonia. We have circumvented the necessity of adding the partial differential equations for mass, momentum, and energy for the ammonia in the liquid phase by certain assumptions. It is assumed that the ammonia fog behaves as an ideal gas including the droplets. A temperature-dependent molecular weight was introduced to simulate the transition from a vapor-droplet cloud to a pure vapor cloud of ammonia. Likewise, the vaporization of ammonia was spread out over a temperature range. Mass, momentum, energy, and total ammonia is conserved rigorously. The observed features of the ammonia spill simulation have pointed out phenomena that could not be predicted in simpler calculations. Perhaps the most obvious feature is the cloud bifurcation due to the strength of the gravity current relative to the ambient wind. The gravity spreading of the denser ammonia fog significantly perturbs the unidirectional windfield in the vicinity of the spill, setting up complex eddy patterns in the cloud which are enhanced by ground heating and warm dry air entrainment. The lower concentrations appear to lift off by a buoyancy-induced flow. The ammonia cloud, rather than being cigar shaped as assumed in simpler models, ranges from pancake shaped to pear shaped, depending upon the ambient windfield. The fact that the ammonia cloud remains cold, very low, and wide is in qualitative agreement with some of the large-scale ammonia spill accidents. 14 figures.

  9. ParadigmParadigm Concrete RecyclingConcrete Recycling

    E-print Network

    ParadigmParadigm Concrete RecyclingConcrete Recycling #12;Recycled ConcreteRecycled Concrete ·· Whatever steel goes into PCC must comeWhatever steel goes into PCC must come out for recycleout for recycle ·· Aggregates have a big impact on the costAggregates have a big impact on the cost of recyclingof recycling

  10. Recycling Research. Tracking Trash.

    ERIC Educational Resources Information Center

    DeLago, Louise Furia

    1991-01-01

    An activity in which students research the effectiveness of recycling is presented. Students compare the types and amount of litter both before and after recycling is implemented. Directions for the activity and a sample data sheet are included. (KR)

  11. Recycling overview in Sweden

    SciTech Connect

    Not Available

    1989-07-01

    This article discusses the recycling programs currently in use in Sweden. Recycling of newspapers, batteries, plastics are all mentioned in this report by the Swedish Association of Public Cleansing and Solid Waste Management.

  12. Bronchiectasis following pulmonary ammonia burn

    SciTech Connect

    Hoeffler, H.B.; Schweppe, H.I.; Greenberg, S.D.

    1982-12-01

    Long-term follow-up of the pulmonary lesions of severe exposure to ammonia in humans has seldom been documented, and development of bronchiectasis continues to be of concern. We studied a previously healthy 30-year-old woman whose lungs at time of necropsy, three years after massive exposure to ammonia fumes, had extensive cylindrical and saccular bronchiectasis. We concluded that massive exposure to ammonia can lead to bronchiectasis. It is not known, however, whether the bronchiectasis resulted from chemical injury by ammonia or from a superimposed bacterial bronchitis.

  13. Recycling and the automobile

    SciTech Connect

    Holt, D.J.

    1993-10-01

    This article examines the current status of automobile recycling and contains a summary of a survey which points out the major drivers and their impacts on automotive recycling. The topics of the article include computerized dismantling, polyurethane, sheet molding compound, polyester, thermoplastic polyester, recycling salvaged parts, vinyl and automotive shredder residue.

  14. Buying recycled helps market

    SciTech Connect

    Watts, G. [City of Thousand Oaks, CA (United States)

    1996-08-01

    The waste reduction and recycling program of Thousand Oaks, California is summarized. Descriptions of the program, market development for recycled products, business development, and economic development are provided. The emphasis of the program is on market development for recycled products. Procurement guidelines used by the city are reprinted in the paper.

  15. Recycling of automotive aluminum

    Microsoft Academic Search

    Jirang CUI; Hans J. ROVEN

    2010-01-01

    With the global warming of concern, the secondary aluminum stream is becoming an even more important component of aluminum production and is attractive because of its economic and environmental benefits. In this work, recycling of automotive aluminum is reviewed to highlight environmental benefits of aluminum recycling, use of aluminum alloys in automotive applications, automotive recycling process, and new technologies in

  16. Rethink, Rework, Recycle.

    ERIC Educational Resources Information Center

    Wrhen, Linda; DiSpezio, Michael A.

    1991-01-01

    Information about the recycling and reuse of plastics, aluminum, steel, glass, and newspapers is presented. The phases of recycling are described. An activity that allows students to separate recyclable materials is included. The objectives, a list of needed materials, and procedure are provided. (KR)

  17. The Sustainability of Recycling.

    ERIC Educational Resources Information Center

    Juniper, Christopher

    1993-01-01

    Describes the need for closing the business cycle in the recycling process. Discusses whether the government should mandate or the free market create uses for recycled products. Presents challenges associated with marketing recycled materials including what has been and what needs to be done to stimulate markets, encourage business, and balance…

  18. RESOURCE GUIDE RECYCLING ELECTRONICS

    E-print Network

    Danforth, Bryan Nicholas

    RESOURCE GUIDE RECYCLING ELECTRONICS Batteries and Accessories Office Depot Cell Phones Any Verizon and Recycling Sprecher Institute for Comparative Cancer Research USE BIODEGRADABLE DETERGENTS that use PLANT://www.thesoftlanding.com/ AVOIDING BISPHENOL-A Eden Organics Beans http://www.edenfoods.com/ CD and DVD recycling http

  19. The Dimension of Projections of Fractal Percolations

    NASA Astrophysics Data System (ADS)

    Rams, Micha?; Simon, Károly

    2014-02-01

    Fractal percolation or Mandelbrot percolation is one of the most well studied families of random fractals. In this paper we study some of the geometric measure theoretical properties (dimension of projections and structure of slices) of these random sets. Although random, the geometry of those sets is quite regular. Our results imply that, denoting by a typical realization of the fractal percolation on the plane, If then for all lines ? the orthogonal projection E ? of E to ? has the same Hausdorff dimension as E,

  20. Process for removal of ammonia and acid gases from contaminated waters

    DOEpatents

    King, C. Judson (Kensington, CA); MacKenzie, Patricia D. (Berkeley, CA)

    1985-01-01

    Contaminating basic gases, i.e., ammonia, and acid gases, e.g., carbon dioxide, are removed from process waters or waste waters in a combined extraction and stripping process. Ammonia in the form of ammonium ion is extracted by an immiscible organic phase comprising a liquid cation exchange component, especially an organic phosphoric acid derivative, and preferably di-2-ethyl hexyl phosphoric acid, dissolved in an alkyl hydrocarbon, aryl hydrocarbon, higher alcohol, oxygenated hydrocarbon, halogenated hydrocarbon, and mixtures thereof. Concurrently, the acidic gaseous contaminants are stripped from the process or waste waters by stripping with steam, air, nitrogen, or the like. The liquid cation exchange component has the ammonia stripped therefrom by heating, and the component may be recycled to extract additional amounts of ammonia.

  1. Equilibrium ammonium concentration in slurry mix evaporator condensate tank (SMECT) with ammonia scrubbers

    SciTech Connect

    Lambert, D.P.

    1992-09-25

    During design reviews of the Recycle Colection Tank (RCT) at the Savannah River Site it was determined that in all cases the RCT scrub solution could not be routed to the RCT. During transfers to the tank farm (estimated ten hour cycle), the ammonia evolved from the RCT is scrubbed by the RCT scrubber and the ammonia scrub water must be returned to the SMECT. The result of this is an increased steady state concentration of ammonium in the SMECT water used for the ammonia scrubbers. The maximum ammonium concentration is necessary for the sizing of the ammonia scrubbers for the Sludge Receipt and Adjustment Tank (SRAT),Slurry Mix Evaporator (SME), and RCT.

  2. Process for removal of ammonia and acid gases from contaminated waters

    DOEpatents

    King, C.J.; Mackenzie, P.D.

    1982-09-03

    Contaminating basic gases, i.e., ammonia and acid gases, e.g., carbon dioxide, are removed from process waters or waste waters in a combined extraction and stripping process. Ammonia in the form of ammonium ion is extracted by an immiscible organic phase comprising a liquid cation exchange component, especially an organic phosphoric acid derivative, and preferably di-2-ethyl hexyl phosphoric acid, dissolved in an alkyl hydrocarbon, aryl hydrocarbon, higher alcohol, oxygenated hydrocarbon, halogenated hydrocarbon, and mixtures thereof. Concurrently, the acidic gaseous contaminants are stripped from the process or waste waters by stripping with stream, air, nitrogen, or the like. The liquid cation exchange component has the ammonia stripped therefrom by heating, and the component may be recycled to extract additional amounts of ammonia.

  3. Connectivity percolation in suspensions of hard platelets

    E-print Network

    Maneesh Mathew; Tanja Schilling; Martin Oettel

    2012-04-13

    We present a study on connectivity percolation in suspensions of hard platelets by means of Monte Carlo simulation. We interpret our results using a contact-volume argument based on an effective single--particle cell model. It is commonly assumed that the percolation threshold of anisotropic objects scales as their inverse aspect ratio. While this rule has been shown to hold for rod-like particles, we find that for hard plate-like particles the percolation threshold is non-monotonic in the aspect ratio. It exhibits a shallow minimum at intermediate aspect ratios and then saturates to a constant value. This effect is caused by the isotropic-nematic transition pre-empting the percolation transition. Hence the common strategy to use highly anisotropic, conductive particles as fillers in composite materials in order to produce conduction at low filler concentration is expected to fail for plate-like fillers such as graphene and graphite nanoplatelets.

  4. Equation of state of ammonia

    NASA Astrophysics Data System (ADS)

    Mulford, R.; Swift, D. C.; Hamel, S.

    2014-05-01

    Ammonia and water are critical components of extraterrestrial bodies, determining the density and physical properties of the Outer Planets, their moons, and of extrasolar planets. Ammonia is unusual in having a high heat capacity relative to other molecular species. Equations of state (EOS) are presented for ammonia and for mixtures of ammonia and water. Their properties are discussed in terms of chemical compositions that evolve as pressure and temperature are varied. The NH4OH hydrate of ammonia is known to exist as a separate molecular species at pressures above about 5 GPa, and an effort was made to include reaction between NH3 and H2O in the mixture EOS. The EOS are suitable for calculating structures of icy planets and exoplanets, and of impacts. mass-radius relations which bound the possible interpretations of composition and structure for extraterrestrial bodies of unknown composition, such as exoplanets.

  5. Modeling of heat generation in ammonia-treated solid rocket propellant

    SciTech Connect

    Raun, R.L.; Isom, K.B. [Hercules, Inc., Magna, UT (United States)] [Hercules, Inc., Magna, UT (United States)

    1995-06-01

    With the end of the Cold War, safe, environmentally sound separation, recycling, and disposal of ingredients in solid rocket propellants and munitions has become a national priority. One approach to demilitarize solid rocket propellants is treatment with ammonia. Ammonia extracts the oxidizers ammonium perchlorate and HMX, yielding a solid reside that is more suitable for incineration and less sensitive to impact and other modes of accidental initiation. Ammonia treatment of nitroglycerin-containing propellants is complicated by an exothermic reaction between ammonia and nitroglycerin. If not removed, the heat generated by this reaction can cause propellant ignition. To help design safe treatment processes, a model for the ammonia-propellant reaction was developed, which integrates transient energy and species conservation equations to simulate ammonia diffusion, heat generation, and heat flow in a propellant and in the solid residue resulting from ammonia treatment. It was calibrated using residue thickness and thermocouple data for one propellant. The calibrated model was used to predict conditions leading to ignition of thin propellant strips. The results agree well with experimental observations.

  6. St Andrews Recycling Points Recycling Points are situated locally to

    E-print Network

    St Andrews, University of

    St Andrews Recycling Points Recycling Points are situated locally to allow you to recycle the following materials: To find your nearest Recycling Point please visit www.fifedirect.org.uk/wasteaware or call the Recycling Helpline on 08451 55 00 22. R&A GOLF CLUB OLD COURSE HOTEL UNIVERSITY NORTH HAUGH

  7. Ammonia Ice Clouds on Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The top cloud layer on Jupiter is thought to consist of ammonia ice, but most of that ammonia 'hides' from spectrometers. It does not absorb light in the same way ammonia does. To many scientists, this implies that ammonia churned up from lower layers of the atmosphere 'ages' in some way after it condenses, possibly by being covered with a photochemically generated hydrocarbon mixture. The New Horizons Linear Etalon Imaging Spectral Array (LEISA), the half of the Ralph instrument that is able to 'see' in infrared wavelengths that are absorbed by ammonia ice, spotted these clouds and watched them evolve over five Jupiter days (about 40 Earth hours). In these images, spectroscopically identified fresh ammonia clouds are shown in bright blue. The largest cloud appeared as a localized source on day 1, intensified and broadened on day 2, became more diffuse on days 3 and 4, and disappeared on day 5. The diffusion seemed to follow the movement of a dark spot along the boundary of the oval region. Because the source of this ammonia lies deeper than the cloud, images like these can tell scientists much about the dynamics and heat conduction in Jupiter's lower atmosphere.

  8. Multiple-well invasion percolation.

    PubMed

    Araújo, A D; Romeu, M C; Moreira, A A; Andrade, R F S; Andrade, J S

    2008-04-01

    When the invasion percolation model is applied as a simplified model for the displacement of a viscous fluid by a less viscous one, the distribution of displaced mass follows two distinct universality classes, depending on the criteria used to stop the displacement. Here we study the distribution of mass for this process, in the case where four extraction wells are placed around a single injection well in the middle of a square lattice. Our analysis considers the limit where the pressure of the extraction well Pe is zero; in other words, an extraction well is capped as soon as less viscous fluid reaches that extraction well. Our results show that, as expected, the probability of stopping the production with small amounts of displaced mass is greatly reduced. We also investigate whether or not creating extra extraction wells is an efficient strategy. We show that the probability of increasing the amount of displaced fluid by adding an extra extraction well depends on the total recovered mass obtained before adding this well. The results presented here could be relevant to determine efficient strategies in oil exploration. PMID:18517620

  9. Multiple-well invasion percolation

    NASA Astrophysics Data System (ADS)

    Araújo, A. D.; Romeu, M. C.; Moreira, A. A.; Andrade, R. F. S.; Andrade, J. S., Jr.

    2008-04-01

    When the invasion percolation model is applied as a simplified model for the displacement of a viscous fluid by a less viscous one, the distribution of displaced mass follows two distinct universality classes, depending on the criteria used to stop the displacement. Here we study the distribution of mass for this process, in the case where four extraction wells are placed around a single injection well in the middle of a square lattice. Our analysis considers the limit where the pressure of the extraction well Pe is zero; in other words, an extraction well is capped as soon as less viscous fluid reaches that extraction well. Our results show that, as expected, the probability of stopping the production with small amounts of displaced mass is greatly reduced. We also investigate whether or not creating extra extraction wells is an efficient strategy. We show that the probability of increasing the amount of displaced fluid by adding an extra extraction well depends on the total recovered mass obtained before adding this well. The results presented here could be relevant to determine efficient strategies in oil exploration.

  10. Percolation Centrality: Quantifying Graph-Theoretic Impact of Nodes during Percolation in Networks

    PubMed Central

    Piraveenan, Mahendra; Prokopenko, Mikhail; Hossain, Liaquat

    2013-01-01

    A number of centrality measures are available to determine the relative importance of a node in a complex network, and betweenness is prominent among them. However, the existing centrality measures are not adequate in network percolation scenarios (such as during infection transmission in a social network of individuals, spreading of computer viruses on computer networks, or transmission of disease over a network of towns) because they do not account for the changing percolation states of individual nodes. We propose a new measure, percolation centrality, that quantifies relative impact of nodes based on their topological connectivity, as well as their percolation states. The measure can be extended to include random walk based definitions, and its computational complexity is shown to be of the same order as that of betweenness centrality. We demonstrate the usage of percolation centrality by applying it to a canonical network as well as simulated and real world scale-free and random networks. PMID:23349699

  11. Recycling Service Learning Activity

    NSDL National Science Digital Library

    Renee Faatz

    The recycling project begins with students learning about waste and resources. They complete background assignments about the energy and materials required to manufacture paper, aluminum, etc. They study landfills and the issues related to space, pollution, etc. They look at what is different if these things are recycled. The students work in groups of two or three and adopt and academic building on campus. They educate the staff and faculty about recycling - what can be recycled and where. They arrange to pick-up paper from each office. My hope is that the college faculty, staff and students will eventually recycle paper at common bins and that our project will progress to adding other recyclables to our project.

  12. Ammonia transport by terrestrial and aquatic insects

    Microsoft Academic Search

    Dirk Weihrauch; Andrew Donini; Michael J. O’Donnell

    Ammonia, an end product from amino acid and nucleic acid metabolism, is highly toxic for most animals. This review will provide an update on nitrogen metabolism in terrestrial and aquatic insects with emphasis on ammonia generation and transport.Aspects that will be discussed include metabolic pathways of nitrogenous compounds, the origin of ammonia and other nitrogenous waste products, ammonia toxicity, putative

  13. ENGINEERING DESIGN CONFIGURATIONS FOR BIOLOGICAL AMMONIA REMOVAL

    EPA Science Inventory

    Many regions in the United States have excessive levels of nutrients including ammonia in their source waters. For example, farming and agricultural sources of ammonia in the Midwest contribute to relatively high levels of ammonia in many ground waters. Although ammonia in water ...

  14. Benchmarking survey for recycling.

    SciTech Connect

    Marley, Margie Charlotte; Mizner, Jack Harry

    2005-06-01

    This report describes the methodology, analysis and conclusions of a comparison survey of recycling programs at ten Department of Energy sites including Sandia National Laboratories/New Mexico (SNL/NM). The goal of the survey was to compare SNL/NM's recycling performance with that of other federal facilities, and to identify activities and programs that could be implemented at SNL/NM to improve recycling performance.

  15. AQUEOUS AMMONIA EQUILIBRIUM - TABULATION OF PERCENT UN-IONIZED AMMONIA

    EPA Science Inventory

    The percent of un-ionized ammonia as a function of pH and temperature in aqueous ammonia solutions of zero salinity is presented in tabular form over the following ranges: temperature 0.0 to 40.0 C in increments of 0.2 degree, and pH 5.00 to 12.00 in increments of 0.01 pH unit....

  16. Municipal solid waste recycling issues

    Microsoft Academic Search

    Lester B. Lave; Chris T. Hendrickson; Noellette M. Conway-Schempf; Francis C. McMichael

    1999-01-01

    Municipal solid waste (MSW) recycling targets have been set nationally and in many states. Unfortunately, the definitions of recycling, rates of recycling, and the appropriate components of MSW vary. MSW recycling has been found to be costly for most municipalities compared to landfill disposal. MSW recycling policy should be determined by the cost to the community and to society more

  17. Factors Influencing Household Recycling Behavior

    Microsoft Academic Search

    Stuart Oskamp; Maura J. Harrington; Todd C. Edwards; Deborah L. Sherwood; Shawn M. Okuda; Deborah C. Swanson

    1991-01-01

    To investigate factors encouraging or deterring recycling, telephone interviews were used to study recycling behavior, attitudes, and knowledge of 221 randomly selected adults in a suburban city that had begun a citywide curbside recycling program within the past year. Approximately 40% reported participation in the curbside recycling program, and nearly 20% more claimed that their household had been recycling in

  18. Announcing: All Recycling Reduce your

    E-print Network

    Papautsky, Ian

    Announcing: All Recycling Go Green! Reduce your contribution to the landfill, by choosing to voluntarily recycle acceptable items in the green All Recycling toters and containers around campus. ONLY THE ITEMS BELOW ARE ACCEPTED FOR ALL RECYCLING Please do not contaminate the recycling containers with trash

  19. Proton percolation on hydrated lysozyme powders

    PubMed Central

    Careri, G.; Giansanti, A.; Rupley, John A.

    1986-01-01

    The framework of percolation theory is used to analyze the hydration dependence of the capacitance measured for protein samples of pH 3-10, at frequencies from 10 kHz to 4 MHz. For all samples there is a critical value of the hydration at which the capacitance sharply increases with increase in hydration level. The threshold hc = 0.15 g of water per g of protein is independent of pH below pH 9 and shows no solvent deuterium isotope effect. The fractional coverage of the surface at hc is in close agreement with the prediction of theory for surface percolation. We view the protonic conduction process described here for low hydration and previously for high hydration as percolative proton transfer along threads of hydrogen-bonded water molecules. A principal element of the percolation picture, which explains the invariance of hc to change in pH and solvent, is the sudden appearance of long-range connectivity and infinite clusters at the threshold hc. The relationship of the protonic conduction threshold to other features of protein hydration is described. The importance of percolative processes for enzyme catalysis and membrane transport is discussed. PMID:16593756

  20. Satellite Observations of Tropospheric Ammonia

    NASA Astrophysics Data System (ADS)

    Shephard, M. W.; Luo, M.; Rinsland, C. P.; Cady-Pereira, K. E.; Beer, R.; Pinder, R. W.; Henze, D.; Payne, V. H.; Clough, S.; Rodgers, C. D.; Osterman, G. B.; Bowman, K. W.; Worden, H. M.

    2008-12-01

    Global high-spectral resolution (0.06 cm-1) nadir measurements from TES-Aura enable the simultaneous retrieval of a number of tropospheric pollutants and trace gases in addition to the TES standard operationally retrieved products (e.g. carbon monoxide, ozone). Ammonia (NH3) is one of the additional species that can be retrieved in conjunction with the TES standard products, and is important for local, regional, and global tropospheric chemistry studies. Ammonia emissions contribute significantly to several well-known environmental problems, yet the magnitude and seasonal/spatial variability of the emissions are poorly constrained. In the atmosphere, an important fraction of fine particulate matter is composed of ammonium nitrate and ammonium sulfate. These particles are statistically associated with health impacts. When deposited to ecosystems in excess, nitrogen, including ammonia can cause nutrient imbalances, change in ecosystem species composition, eutrophication, algal blooms and hypoxia. Ammonia is also challenging to measure in-situ. Observations of surface concentrations are rare and are particularly sparse in North America. Satellite observations of ammonia are therefore highly desirable. We recently demonstrated that tropospheric ammonia is detectable in the TES spectra and presented some corresponding preliminary retrievals over a very limited range of conditions (Beer et al., 2008). Presented here are results that expand upon these initial TES ammonia retrievals in order to evaluate/validate the retrieval results utilizing in-situ surface observations (e.g. LADCO, CASTNet, EPA /NC State) and chemical models (e.g. GEOS-Chem and CMAQ). We also present retrievals over regions of interest that have the potential to help further understand air quality and the active nitrogen cycle. Beer, R., M. W. Shephard, S. S. Kulawik, S. A. Clough, A. Eldering, K. W. Bowman, S. P. Sander, B. M. Fisher, V. H. Payne, M. Luo, G. B. Osterman, and J. R. Worden, First satellite observations of lower tropospheric ammonia and methanol, Geophysical Res. Letters, 35, L09801, doi:10.1029/2008GL033642, 2008.

  1. Percolation, Cluster and Pair Correlation Analysis (L22)

    E-print Network

    Rollett, Anthony D.

    1 Carnegie Mellon MRSEC Percolation, Cluster and Pair Correlation Analysis (L22) Texture boundary properties and texture. · Introduce cluster analysis via nearest neighbor distances · Introduce objects are connected to each other. · More specifically, percolation is the analysis of clusters

  2. Clustering and percolation for dimerizing penetrable spheres

    SciTech Connect

    Weist, A.O.; Glandt, E.D. (Department of Chemical Engineering, University of Pennsylvania, Philadelphia, Pennsylvania (USA))

    1991-12-01

    Wertheim's dual density formalism is applied to study the percolation behavior of dimerizing permeable spheres. The model is that of permeable spheres introduced by Blum and Stell as a generalized potential having ideal-gas (randomly centered) spheres as one limit and Percus--Yevick hard spheres as the other. Both thermodynamic results (pressure and site--site pair-correlation functions) and connectivity results (percolation threshold and site--site pair-connectedness functions) are determined for mixtures of dumbbells and spheres as a function of the penetrability factor {epsilon}, the bond length {ital L} and the fraction {ital x}{sub 1} of spheres forming dumbbells. A critical bond length {ital L}=0.553 was found for which the percolation threshold is independent of the amount of dimerization.

  3. Amorphous solidification and percolation in two dimensions

    NASA Astrophysics Data System (ADS)

    Castillo, Horacio E.; Goldbart, Paul M.; Peng, Weiqun

    2000-03-01

    Since the pioneering work of Stauffer and de Gennes, it has been assumed that the amorphous solidification of randomly crosslinked macromolecular systems (RCMS) can be described in terms of percolation theory. Recent detailed studies of RCMS have brought out a mixed picture in this regard: while for some aspects of the transition (e.g. the behavior of the gel fraction in 3D) there is a direct correspondence with percolation, for others (e.g. the elastic properties) this correspondence is more problematic. We show that the lower critical dimension (LCD) of amorphous solidification is two, as opposed to one in percolation. Studying amorphous solidification at the LCD is a delicate matter, owing to the random character of the quasi-ordering involved. We compute the behavior of order parameter correlations in RCMS at the LCD, and compare RCMS quasi-long-range ordering with that found in other 2D systems.

  4. Recycling the junk car

    Microsoft Academic Search

    Harwood

    1977-01-01

    A systems approach to recycling junk cars as a major renewable resource is proposed, although this will require some legislative, technological, and economic changes. The volume of materials contained in automobiles makes them the major source of scrap steel, but recycling can also yield secondary supplies of zinc, copper, aluminum, rubber, and plastics. Economic considerations have historically singled out scrap

  5. Recycling at Camp.

    ERIC Educational Resources Information Center

    Cummins, William M.

    1988-01-01

    Outlines a Michigan summer camp's efforts to reduce solid waste disposal by recycling cardboard, tin, glass, aluminum, and plastic milk containers. Points out variables affecting the success of such efforts. Discusses Michigan state funding for the development of recycling programs. (SV)

  6. AIRCRAFT INDUSTRY WASTEWATER RECYCLING

    EPA Science Inventory

    The feasibility of recycling certain categories of water used in the manufacture of airplanes was demonstrated. Water in four categories was continuously recycled in 380-liter (100-gallon) treatment plants; chemical process rinse water, dye-penetrant crack-detection rinse water, ...

  7. Making Recycled Paper

    NSDL National Science Digital Library

    2005-01-01

    This video and accompanying text describe the three-pronged resource conservation strategy known as "reduce, reuse, and recycle". The video segment, adapted from the television program 'ZOOM', features cast members demonstrating how something that might otherwise be discarded, such as newspaper, can be recycled to create a functional or even beneficial new product. Questions for discussion are also provided.

  8. Carbon dioxide recycling

    EPA Science Inventory

    The recycling of carbon dioxide to methanol and dimethyl ether is seen to offer a substantial route to renewable and environmentally carbon neutral fuels. One of the authors has championed the ?Methanol Economy" in articles and a book. By recycling ambient CO2, the authors argue ...

  9. Partnership: Recycling $/$ Outdoor Education.

    ERIC Educational Resources Information Center

    Weir, Phil

    1996-01-01

    The Ottawa Board of Education (Ontario, Canada) has committed revenues generated by a districtwide recycling program to help fund the MacSkimming Outdoor Education Centre. A partnership between recycling and outdoor education is valuable in developing an environmental ethic among students and in finding new ways to fund outdoor education. (LP)

  10. Is mandated recycling possible

    Microsoft Academic Search

    Cutler

    1988-01-01

    If piles of potentially recyclable materials are accumulated as a result of a mandatory source separation program, what options exist for the community First, it could attempt to market the recyclables through normal commercial channels. Second, the community could attempt to market the materials at lower prices to the consumers, since any contribution above available disposal cost is a profit

  11. Recycling into Art

    NSDL National Science Digital Library

    Debra Fioranelli

    2000-10-01

    This interdisciplinary unit weaves art and science together to help students appreciate the importance of recycling. In this engaging activity, students collected items worthy of recycling from home, and with the help of the art teacher, used a loom to cr

  12. Visiting a Recycling Plant

    NSDL National Science Digital Library

    2005-10-21

    In this ZOOM video segment, cast member Francesco follows the paper trail to find out what happens to his recyclables. He visits a material recovery center and learns how paper is recycled and the number of trees that are saved as a result.

  13. The Fermilab recycler ring

    SciTech Connect

    Martin Hu

    2001-07-24

    The Fermilab Recycler is a permanent magnet storage ring for the accumulation of antiprotons from the Antiproton Source, and the recovery and cooling of the antiprotons remaining at the end of a Tevatron store. It is an integral part of the Fermilab III luminosity upgrade. The following paper describes the design features, operational and commissioning status of the Recycler Ring.

  14. Variational problems with percolation: rigid spin systems

    E-print Network

    G. Scilla

    2014-07-25

    In this paper we describe the asymptotic behavior of rigid spin lattice energies by exhibiting a continuous interfacial limit energy as scaling to zero the lattice spacing. The limit is not trivial below a percolation threshold: it can be characterized by two phases separated by an interface. The macroscopic surface tension at this interface is defined through a first-passage percolation formula, related to the chemical distance on the square lattice. We also show a continuity result, that is the homogenization of rigid spin system is a limit case of the elliptic random homogenization.

  15. Percolation Theory of Nonlinear Circuit Elements

    NASA Astrophysics Data System (ADS)

    Kenkel, Stephen W.; Straley, Joseph P.

    1982-09-01

    Percolation theory is extended to the case of circuit elements with nonlinear I-V characteristics, particularly the special cases V=I?r, which form the universality classes. Near the percolation threshold the "conductance" IV1? vanishes like (p-pc)t, where t depends on ? and dimensionality. The Skal-Shklovskii-De Gennes model gives t(?)=(d-1)?+(?-?)?, where ? is only weakly dependent on ? and d, and approaches unity at d=6. Renormalization methods are used to study the ? dependence of t in two dimensions.

  16. On the Aizenman Exponent in Critical Percolation

    NASA Astrophysics Data System (ADS)

    Shchur, L. N.; Rostunov, T.

    2002-10-01

    The probabilities of clusters spanning a hypercube of dimensions two to seven along one axis of a percolation system under criticality were investigated numerically. We used a modified Hoshen--Kopelman algorithm combined with Grassberger's "go with the winner" strategy for the site percolation. We carried out a finite-size analysis of the data and found that the probabilities confirm Aizenman's proposal of the multiplicity exponent for dimensions three to five. A crossover to the mean-field behavior around the upper critical dimension is also discussed.

  17. Percolation with a threshold at zero: A new universality class

    Microsoft Academic Search

    S. A. Trugman; Abel Weinrib

    1985-01-01

    We propose a new continuum percolation model that has a percolation threshold at zero: The network conducts no matter how small the volume fraction of conductor. The model is in a different universality class from ordinary percolation, despite the fact that it is defined by a potential with only short-range correlations. The conductivity exponent t0 in two dimensions is calculated

  18. Lattice trees, percolation and super-Brownian motion

    E-print Network

    Slade, Gordon

    Lattice trees, percolation and super-Brownian motion Gordon Slade April 2, 1999 Abstract This paper and the incipient infinite percolation cluster, in high dimen- sions. A potential extension to oriented percolation (ISE), a close relative of super-Brownian motion (SBM). SBM is a funda- mental example of a measure

  19. Mono-fermentation of chicken manure: ammonia inhibition and recirculation of the digestate.

    PubMed

    Nie, Hong; Jacobi, H Fabian; Strach, Katrin; Xu, Chunming; Zhou, Hongjun; Liebetrau, Jan

    2015-02-01

    The effects of ammonia concentration on the performance and stability of mono-fermentation of chicken manure were investigated in a lab-scale continuous stirred tank reactor at 40 °C. Technical stripping was performed to remove ammonia from the liquid fraction of digestate, and the entire product was recycled to the fermenter to control ammonia concentration in the fermenter. Organic loading rate (OLR) of 5.3 gVS/(L d) was achieved with an average free ammonia nitrogen (FAN) concentration of 0.77 g/L and a specific gas yield of 0.39 L/gVS. When OLR was increased to 6.0 gVS/(L d), stable operation could be obtained with an average FAN concentration of 0.86 g/L and a specific gas yield of 0.27 L/gVS. Mono-fermentation of chicken manure was successfully carried out at high ammonia concentrations. Controlled recirculation of treated liquid fraction of digestate could be a solution in large-scale application for both: to avoid ammonia inhibition and minimize digestate. PMID:25266688

  20. Intracage Ammonia Levels in Static and Individually Ventilated Cages Housing C57BL/6 Mice on 4 Bedding Substrates

    PubMed Central

    Ferrecchia, Christie E; Jensen, Kelly; Andel, Roger Van

    2014-01-01

    The relationship among ammonia levels, cage-changing frequency, and bedding types is an important and potentially controversial topic in the laboratory animal science community. Some bedding options may not provide sufficient urine absorption and bacterial regulation to minimize ammonia production during the interval between cage changes. High intracage ammonia levels can cause subclinical degeneration and inflammation of nasal passages, rhinitis and olfactory epithelial necrosis in exposed mice. Here we sought to compare the effects of 4 commonly used bedding substrates (1/4-in. irradiated corncob, reclaimed wood pulp, aspen wood chips, and recycled newspaper) on ammonia generation when housing female C57BL/6 mice in static and individually ventilated caging. Intracage ammonia levels were measured daily for 1 wk (static cage experiment) or 2 wk (IVC experiment). The results of this study suggest that the corncob, aspen wood chip, and recycled newspaper beddings that we tested are suitable for once-weekly cage changing for static cages and for changing every 2 wk for IVC. However, ammonia levels were not controlled appropriately in cages containing reclaimed wood pulp bedding, and pathologic changes occurred within 1 wk in the nares of mice housed on this bedding in static cages. PMID:24602540

  1. MEASUREMENT OF AMMONIA RELEASE FROM SALTSTONE

    SciTech Connect

    Zamecnik, J; Alex Cozzi, A

    2009-01-15

    SRNL was requested by WSRC Waste Solidification Engineering to characterize the release of ammonia from saltstone curing at 95 C by performing experimental testing. These tests were performed with an MCU-type Tank 50H salt simulant containing 0, 50, and 200 mg/L ammonia. The testing program showed that above saltstone made from the 200 mg/L ammonia simulant, the vapor space ammonia concentration was about 2.7 mg/L vapor at 95 C. An upper 95% confidence value for this concentration was found to be 3.9 mg/L. Testing also showed that ammonia was chemically generated from curing saltstone at 95 C; the amount of ammonia generated was estimated to be equivalent to 121 mg/L additional ammonia in the salt solution feed. Even with chemical generation, the ammonia release from saltstone was found to be lower than its release from salt solution only with 200 mg/L ammonia.

  2. Recycle Used Oil on America Recycles Day

    NSDL National Science Digital Library

    Boyd W. White

    2000-11-01

    Motor oil doesn't wear out--it just gets dirty. Students and the general public may not know that used oil can be reused or recycled. The fact is, used oil can be re-fined, blended with additives, and used again. When you consider that 1.4 billion gallons

  3. Interorgan ammonia metabolism in liver failure.

    PubMed

    Olde Damink, Steven W M; Deutz, Nicolaas E P; Dejong, Cornelis H C; Soeters, Peter B; Jalan, Rajiv

    2002-01-01

    In the post-absorptive state, ammonia is produced in equal amounts in the small and large bowel. Small intestinal synthesis of ammonia is related to amino acid breakdown, whereas large bowel ammonia production is caused by bacterial breakdown of amino acids and urea. The contribution of the gut to the hyperammonemic state observed during liver failure is mainly due to portacaval shunting and not the result of changes in the metabolism of ammonia in the gut. Patients with liver disease have reduced urea synthesis capacity and reduced peri-venous glutamine synthesis capacity, resulting in reduced capacity to detoxify ammonia in the liver. The kidneys produce ammonia but adapt to liver failure in experimental portacaval shunting by reducing ammonia release into the systemic circulation. The kidneys have the ability to switch from net ammonia production to net ammonia excretion, which is beneficial for the hyperammonemic patient. Data in experimental animals suggest that the kidneys could have a major role in post-feeding and post-haemorrhagic hyperammonemia.During hyperammonemia, muscle takes up ammonia and plays a major role in (temporarily) detoxifying ammonia to glutamine. Net uptake of ammonia by the brain occurs in patients and experimental animals with acute and chronic liver failure. Concomitant release of glutamine has been demonstrated in experimental animals, together with large increases of the cerebral cortex ammonia and glutamine concentrations. In this review we will discuss interorgan trafficking of ammonia during acute and chronic liver failure. Interorgan glutamine metabolism is also briefly discussed, since glutamine synthesis from glutamate and ammonia is an important alternative pathway of ammonia detoxification. The main ammonia producing organs are the intestines and the kidneys, whereas the major ammonia consuming organs are the liver and the muscle. PMID:12020618

  4. Information technology product recycling. An OEM\\/recycler collaboration

    Microsoft Academic Search

    R. S. Denis; S. Skurnac

    1998-01-01

    Hewlett-Packard's hardware recycling operation has gone through significant changes in the past several years in response to changes in recycling markets and recycling technology, As recently as three years ago, most electronic scrap could be recycled or be sold into secondary markets and generate positive returns for OEMs and equipment brokers. Even two gears ago, integrated circuit values from old

  5. RecycleMania! Improving Waste Reduction and Recycling on

    E-print Network

    Awtar, Shorya

    RecycleMania! Improving Waste Reduction and Recycling on Campus from Universities to Big Business #12;Contact Information Tracy Artley Recycling Coordinator University of Michigan Tel: 734-763-5539 Email: recycle@umich.edu #12;Agenda Waste Impacts of Large Institutions Unique Challenges Overcoming

  6. A Harris-Kesten theorem for confetti percolation

    E-print Network

    Hirsch, Christian

    2012-01-01

    Percolation properties of the dead leaves model, also known as confetti percolation, are considered. More precisely, we prove that the critical probability for confetti percolation with square-shaped grains is 1/2. This result is related to a question of Benjamini and Schramm concerning disk-shaped grains and can be seen as a variant of the Harris-Kesten theorem for bond percolation. The proof is based on techniques developed by Bollob\\'as and Riordan to determine the critical probability for Voronoi and Johnson-Mehl percolation.

  7. Microstructures, percolation thresholds, and rock physical properties

    Microsoft Academic Search

    Y. Gueguen; T. Chelidze; M. Le Ravalec

    1997-01-01

    The physical properties (transport properties and mechanical properties) of porous\\/cracked rocks are mainly functions of their microstructure. In this connection the problem of critical (threshold) porosity for transport, elasticity and mechanical strength is especially important. Two dominant mathematical formalisms — effective medium theory (EMT) and percolation theory — pretend to give answers to this problem. Some of the EMT models

  8. Semioriented bootstrap percolation in three dimensions

    E-print Network

    of a three dimensional semi­oriented bootstrap percolation model, constricted to a 3D cube wrapped to a torus droplet can also shrink. It follows from this result that for the SBP 2;1 model p c = 0, i.e. on the infi

  9. Percolation on general trees and HIV modeling

    NASA Astrophysics Data System (ADS)

    Ahmed, E.; Agiza, H. N.

    1996-12-01

    Percolation on a general tree is studied. A general tree is used to model the transition from HIV infection into AIDS and to explain the large differences of the transition time from one patient to another. HIV has some autoimmune effects due to its low antigenic mutants. Fuzzy mathematics is used to explain these effects.

  10. Asymptotics in High Dimensions for Percolation

    E-print Network

    Grimmett, Geoffrey

    Asymptotics in High Dimensions for Percolation Harry Kesten 1 Abstract We prove that the critical 1 Research supported by the NSF through a grant to Cornell University. #12; 220 Kesten #(p) = #(p, Z (Aizenman, Kesten, and Newman 1987; Gandolfi, Grimmett, and Russo 1988) that if #(p) > 0, then there exists

  11. Incipient infinite clusters in 2D percolation

    NASA Astrophysics Data System (ADS)

    Jarai, Antal

    2000-10-01

    We study several kinds of large clusters in critical two- dimensional percolation, and show that the microscopic (lattice scale) view of these clusters when they are observed from the perspective of one of their sites is described by Kesten's incipient infinite cluster (IIC), as it was conjectured in [Ai97]. This way we relate the IIC to other objects in critical percolation that have been proposed as alternatives [ChChDu, ChCh, AM]. The mentioned relationship is established for spanning clusters, large clusters in a finite box, the inhomogeneous model of J. Chayes, L. Chayes and R. Durrett, and the invaded region in invasion percolation without trapping. Other related theorems are proved. It is shown that for any k >= 1 the difference in size between the k-th and (k + 1)-st largest critical clusters in a finite box goes to infinity in probability as the size of the box goes to infinity. The distribution of the Chayes-Chayes-Durrett cluster is shown to be singular with respect to the IIC. A new upper bound for the growth rate of the invasion percolation cluster, matching the lower bound up to a constant factor, is obtained.

  12. Solvent recycle/recovery

    SciTech Connect

    Paffhausen, M.W.; Smith, D.L.; Ugaki, S.N.

    1990-09-01

    This report describes Phase I of the Solvent Recycle/Recovery Task of the DOE Chlorinated Solvent Substitution Program for the US Air Force by the Idaho National Engineering Laboratory, EG G Idaho, Inc., through the US Department of Energy, Idaho Operations Office. The purpose of the task is to identify and test recovery and recycling technologies for proposed substitution solvents identified by the Biodegradable Solvent Substitution Program and the Alternative Solvents/Technologies for Paint Stripping Program with the overall objective of minimizing hazardous wastes. A literature search to identify recycle/recovery technologies and initial distillation studies has been conducted. 4 refs.

  13. Dragnet: Nonprofit Computer Recyclers

    NSDL National Science Digital Library

    If you have ever wondered what happens to obsolete computers, check out these current awareness Websites. The disposal of computers is classified as hazardous waste, which has become an environmental concern as the number of obsolete computers rises. In fact, the Wisconsin Department of Natural Resources and the State of Massachusetts have banned computer equipment from landfills. Dragnet: Nonprofit Computer Recyclers is an EPA-licensed computer recycling organization that reuses all acceptable components and systems or recycles damaged or unusable components. Rebuilt computer systems are given to "persons with disabilities and persons living in disadvantaged situations."

  14. RETHINKING WASTE, RECYCLING, AND HOUSEKEEPING

    E-print Network

    Howitt, Ivan

    RETHINKING WASTE, RECYCLING, AND HOUSEKEEPING EFFICIENCY.EFFICIENCY. A l GA leaner Green #12 t R li Management Recycling Staff The Office of Waste Reduction & Recycling started in The Office of Waste Reduction & Recycling started in 1990, we have 14 full time staff positions. ·We collect over 40

  15. Authorization Recycling in RBAC Systems

    E-print Network

    Authorization Recycling in RBAC Systems 1Laboratory for Education and Research in Secure Systems ·motivation ·recycling approach recycling algorithms experimental evaluations summary & future work #12 issued before (precise recycling) #12;6 Laboratory for Education and Research in Secure Systems

  16. Nottingham Trent University Plastic Recycling

    E-print Network

    Evans, Paul

    5015/03/08 Nottingham Trent University Plastic Recycling Water and fizzy drinks bottles the caps from any bottles you recycle. Please rinse all plastic bottles and containers before putting them in the recycling bins. #12;5015/03/08 Nottingham Trent University Paper Recycling Office paper Catalogues

  17. RECYCLING RATE STUDY Prepared by

    E-print Network

    Laughlin, Robert B.

    NATIONAL RECYCLING RATE STUDY Prepared by: Smith, Bucklin and Associates, Inc. Market Research and Statistics Division Chicago, Illinois July 2003 PRINTED ON RECYCLED PAPER #12;BCI RECYCLING RATE STUDY TABLE ....................................................................................................1 II. METHODOLOGY A. Total Pounds of Lead Recycled from Batteries

  18. Dual recycling for GEO600

    E-print Network

    A. Freise

    2003-06-12

    Dual recycling is the combination of signal recycling and power recycling; both optical techniques improve the shot-noise-limited sensitivity of interferometric gravitational-wave detectors. In addition, signal recycling can reduce the loss of light power due to imperfect interference and allows, in principle, to beat the standard quantum limit. The interferometric gravitational-wave detector GEO600 is the first detector to use signal recycling. We have recently equipped the detector with a signal-recycling mirror with a transmittance of 1%. In this paper, we present details of the detector commissioning and the first locks of the dual- recycled interferometer.

  19. The Totem Pole Recycled.

    ERIC Educational Resources Information Center

    Sewall, Susan Breyer

    1991-01-01

    Presents an activity that integrates science, environmental education, art, and social studies. Students identify and research an endangered species and construct a totem pole depicting the species using a recyclable material. (MDH)

  20. Recycling and Composting

    NSDL National Science Digital Library

    WGBH Educational Foundation

    2005-12-17

    Students learn about the value renewable resources hold for our society and the broader community of living things. They expand their understanding of two important conservation activities we can engage in: recycling and composting.

  1. Making Recycled Paper

    NSDL National Science Digital Library

    2013-07-08

    In this activity on page 11 of the PDF, learners follow simple steps to recycle old newspaper into new paper. Use this activity to introduce conservation as well as the chemistry of cellulose and how paper products are made.

  2. A Practical Recycling Project . . .

    ERIC Educational Resources Information Center

    Durant, Raymond H.; Mikuska, James M.

    1973-01-01

    Descirbes a school district's recycling program of aluminum lunch trays that are collected after their use. The trays are used as scrap metal in industrial education workshop and used for sand castings. (PS)

  3. Catalytic Organometallic Reactions of Ammonia

    PubMed Central

    Klinkenberg, Jessica L.

    2012-01-01

    Until recently, ammonia had rarely succumbed to catalytic transformations with homogeneous catalysts, and the development of such reactions that are selective for the formation of single products under mild conditions has encountered numerous challenges. However, recently developed catalysts have allowed several classes of reactions to create products with nitrogen-containing functional groups from ammonia. These reactions include hydroaminomethylation, reductive amination, alkylation, allylic substitution, hydroamination, and cross-coupling. This Minireview describes examples of these processes and the factors that control catalyst activity and selectivity. PMID:20857466

  4. 21 CFR 573.180 - Anhydrous ammonia.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Anhydrous ammonia. 573.180 Section 573.180...AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS...Listing § 573.180 Anhydrous ammonia. (a) The food additive...

  5. 21 CFR 573.180 - Anhydrous ammonia.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Anhydrous ammonia. 573.180 Section 573.180...AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS...Listing § 573.180 Anhydrous ammonia. (a) The food additive...

  6. Climate Kids: Recycle This!

    NSDL National Science Digital Library

    2013-11-20

    The site features an online game in which participants keep recyclable items out of the trash by guiding them into proper bins. Accompanying the game is a list of three categories of items that can be recycled, along with the benefits of doing so. This lesson is part of the Climate Kids website, a NASA education resource featuring articles, videos, images and games focused on the science of climate change.

  7. Recycling of nonmetallics

    USGS Publications Warehouse

    Amey, E.B.; Kelly, T.D.

    1996-01-01

    The first factor determining recyclability is the composition of the material itself. Metals, for example, can be reused with little or no loss in quality. Paper and rubber, by this criterion, are less recyclable. Each time paper is recycled, some cellulose fibers are broken. Shorter fibers can mean weaker paper of perceived lower quality and value. Vulcanizing is an irreversible chemical process that precludes recycling rubber in its original form. Both materials may be reused in other applications often of lower value than the original one. To be recyclable, the discarded material must have a collection infrastructure at the source of waste generation, at a central collection site, or at curbside. The recovered material must also have a market. If it is priced noncompetitively or no market exists, if it does not meet specifications, or if it requires special technology investments which cannot be recovered through future sales, the recovered material may be stockpiled or discarded rather than recycled. ?? 1996 International Association for Mathematical Geology.

  8. AMBIENT AMMONIA MEASUREMENTS IN COASTAL SOUTHEASTERN VIRGINIA

    EPA Science Inventory

    Results are presented from a measurement program to test an in situ ammonia measurement technique and to document the temporal and spatial variability associated with ammonia. The ammonia data were accumulated for two sites in coastal Southeastern Virginia from 15 Aug. 1979 to 31...

  9. Glycopyrrolate in toxic exposure to ammonia gas.

    PubMed

    Bhalla, A; Mahi, S; Sharma, N; Singh, S

    2011-01-01

    Ammonia (NH(3)) is a highly water-soluble, colorless, irritant gas with a unique pungent odor. Liquid ammonia stored under high pressure is still widely used for refrigeration in cold stores used for storing grains. Severe toxicity may occur following accidental exposure. We report an interesting case of accidental exposure to ammonia treated with glycopyrrolate along with other supportive measures. PMID:21633586

  10. Optical fiber-based evanescent ammonia sensor

    Microsoft Academic Search

    Wenqing Cao; Yixiang Duan

    2005-01-01

    An optical fiber-based evanescent gaseous ammonia sensor is designed and developed. The sensing dye, bromocresol purple (BCP), is immobilized in the substitutional cladding using sol–gel process. The sensing properties of the optical fiber sensor to gaseous ammonia at room temperature are presented. This newly developed ammonia sensor exhibits good reversibility and repeatability. The effect of different carrier gases, argon, nitrogen,

  11. 8, 54135436, 2008 Ammonia in sulfuric

    E-print Network

    Boyer, Edmond

    ACPD 8, 5413­5436, 2008 Ammonia in sulfuric acid ion induced nucleation I. K. Ortega et al. Title.0 License. Atmospheric Chemistry and Physics Discussions The role of ammonia in sulfuric acid ion induced­5436, 2008 Ammonia in sulfuric acid ion induced nucleation I. K. Ortega et al. Title Page Abstract

  12. Hydrogen production using ammonia borane

    DOEpatents

    Hamilton, Charles W; Baker, R. Thomas; Semelsberger, Troy A; Shrestha, Roshan P

    2013-12-24

    Hydrogen ("H.sub.2") is produced when ammonia borane reacts with a catalyst complex of the formula L.sub.nM-X wherein M is a base metal such as iron, X is an anionic nitrogen- or phosphorus-based ligand or hydride, and L is a neutral ancillary ligand that is a neutral monodentate or polydentate ligand.

  13. 7, 383403, 2007 Ammonia aged

    E-print Network

    Paris-Sud XI, Université de

    - tures and relative humidities with a continuous flow diffusion chamber. The montmo- rillonite particles chamber. There was no significant change in the mineral dust particle size distribution due to the ammonia of clouds by acting as cloud condensation nuclei (CCN) and ice nuclei (IN) (Knopf and Koop, 2006; Ramanathan

  14. Cooperation percolation in spatial prisoner's dilemma game

    E-print Network

    Yang, Han-Xin; Wang, Wen-Xu

    2015-01-01

    The paradox of cooperation among selfish individuals still puzzles scientific communities. Although a large amount of evidence has demonstrated that cooperator clusters in spatial games are effective to protect cooperators against the invasion of defectors, we continue to lack the condition for the formation of a giant cooperator cluster that assures the prevalence of cooperation in a system. Here, we study the dynamical organization of cooperator clusters in spatial prisoner's dilemma game to offer the condition for the dominance of cooperation, finding that a phase transition characterized by the emergence of a large spanning cooperator cluster occurs when the initial fraction of cooperators exceeds a certain threshold. Interestingly, the phase transition belongs to different universality classes of percolation determined by the temptation to defect $b$. Specifically, on square lattices, $1percolation, whereas $3/2

  15. Asymmetry of near-critical percolation interfaces

    E-print Network

    Nolin, Pierre

    2007-01-01

    We study the possible scaling limits of percolation interfaces in two dimensions on the triangular lattice. When one lets the percolation parameter p(N) vary with the size N of the box that one is considering, three possibilities arise in the large-scale limit. It is known that when p(N) does not converge to 1/2 fast enough, then the scaling limits are degenerate, whereas if p(N) - 1 / 2 goes to zero quickly, the scaling limits are SLE(6) as when p=1/2. We study some properties of the (non-void) intermediate regime where the large scale behavior is neither SLE(6) nor degenerate. We prove that in this case, the law of any scaling limit is singular with respect to that of SLE(6), even if it is still supported on the set of curves with Hausdorff dimension equal to 7/4.

  16. Percolation in the Rayleigh-Benard convection

    NASA Astrophysics Data System (ADS)

    Shibata, Hiroshi

    2006-11-01

    The divergence of the viscosity coefficient and the heat conductivity in the Rayleigh-Benard convection was found in the numerical calculation from 2004 to 2005[1-3]. The interpretation for this phenomenon from the viewpoint of physics is incomplete. The present author proposes a physical interpretation introducing the percolation theory[4]. The temperature difference region where the divergence of the viscosity coefficient occurs depends on the system size length. This system size dependency gives us an insight for the physics in the divergence of the viscosity coefficient in the Rayleigh-Benard convection. [1] H. Shibata, Momentum flux in Rayleigh-Benard convection, Physica A 333, 71-86(2004). [2] H. Shibata, Momentum flux in Rayleigh-Benard convection II, Physica A 345, 448-456(2005). [3] H. Shibata, Heat flux in Rayleigh-Benard convection, Physica A 352, 335-346(2005). [4] D. Stauffer, Introduction to Percolation Theory (Taylor & Francis, London, 1985).

  17. Fragmentation of percolation clusters in general dimensions.

    PubMed

    Cheon, M; Heo, M; Chang, I; Stauffer, D

    1999-05-01

    The scaling behavior for binary fragmentation of critical percolation clusters in general dimensions is investigated by Monte Carlo simulation as well as by exact series expansions. We obtain values of critical exponents lambda and phi describing the scaling of the fragmentation rate and the distribution of cluster masses produced by binary fragmentation. Our results for lambda and phi in two to nine dimensions agree with the conjectured scaling relation sigma=1+lambda-phi by Edwards and co-workers [Phys. Rev. Lett. 68, 2692 (1992); Phys. Rev. A 46, 6252 (1992)], which in turn excludes the other scaling relations suggested by Gouyet (for d=2), and by Roux and Guyon [J. Phys. A 22, 3693 (1989)], where sigma is the crossover exponent for the cluster numbers in percolation theory. PMID:11969506

  18. From Percolation to Logarithmic Conformal Field Theory

    E-print Network

    Pierre Mathieu; David Ridout

    2007-10-19

    The smallest deformation of the minimal model M(2,3) that can accommodate Cardy's derivation of the percolation crossing probability is presented. It is shown that this leads to a consistent logarithmic conformal field theory at c=0. A simple recipe for computing the associated fusion rules is given. The differences between this theory and the other recently proposed c=0 logarithmic conformal field theories are underlined. The discussion also emphasises the existence of invariant logarithmic couplings that generalise Gurarie's anomaly number.

  19. Pacman Percolation and the Glass Transition

    E-print Network

    Raffaele Pastore; Massimo Pica Ciamarra; Antonio Coniglio

    2014-05-22

    We investigate via Monte Carlo simulations the kinetically constrained Kob-Andersen lattice glass model showing that, contrary to current expectations, the relaxation process and the dynamical heterogeneities seems to be characterized by different time scales. Indeed, we found that the relaxation time is related to a reverse percolation transition, whereas the time of maximum heterogeneity is related to the spatial correlation between particles. This investigation leads to a geometrical interpretation of the relaxation processes and of the different observed time scales.

  20. Contact percolation transition in athermal particulate systems.

    PubMed

    Shen, Tianqi; O'Hern, Corey S; Shattuck, M D

    2012-01-01

    Typical quasistatic compression algorithms for generating jammed packings of purely repulsive, frictionless particles begin with dilute configurations and then apply successive compressions with the relaxation of the elastic energy allowed between each compression step. It is well known that during isotropic compression these systems undergo a first-order-like jamming transition at packing fraction ?(J) from an unjammed state with zero pressure and no force-bearing contacts to a jammed, rigid state with nonzero pressure, a percolating network of force-bearing contacts, and contact number z=2d, where d is the spatial dimension. Using computer simulations of two-dimensional systems with monodisperse and bidisperse particle size distributions, we investigate the second-order-like contact percolation transition, which precedes the jamming transition with ?(P)percolation transition also signals the onset of a nontrivial mechanical response to applied stress. Our results show that cooperative particle motion occurs in unjammed systems significantly below the jamming transition for ?(P)?(J). PMID:22400566

  1. Hidden percolation transition in kinetic replication process

    NASA Astrophysics Data System (ADS)

    Timonin, P. N.; Chitov, G. Y.

    2015-04-01

    The one-dimensional kinetic contact process with parallel update is introduced and studied by the mean-field approximation and Monte Carlo (MC) simulations. Contrary to a more conventional scenario with single active phase for 1d models with Ising-like variables, we find two different adjacent active phases in the parameter space of the proposed model with a second-order transition between them and a multiphase point where the active and the absorbing phases meet. While one of the active phases is quite standard with a smooth average filling of the space–time lattice, the second active phase demonstrates a very subtle (hidden) percolating order which becomes manifest only after certain transformation from the original model. We determine the percolation order parameter for active–active phase transition and discuss such hidden orders in other low-dimensional systems. Our MC data demonstrate finite-size critical and near-critical scaling of the order parameter relaxation for the two phase transitions. We find three independent critical indices for them and conclude that they both belong to the directed percolation universality class.

  2. Percolative phenomena in branched reverse micelles

    NASA Astrophysics Data System (ADS)

    Aliotta, F.; Fazio, B.

    2002-02-01

    The role played by the solvation water molecules on the macroscopically observed sol-gel transition in lecithin/cyclohexane/water reverse micelles is investigated. The self-diffusion properties of both the surfactant and the water molecules entrapped in the micellar cores are investigated by quasi-elastic neutron scattering, while dielectric relaxation and conductivity measurements furnish information on the structural relaxation processes taking place in the system. The obtained results are compared with the experimental indications for AOT/cyclohexane/water systems. The data from lecithin-based systems can be interpreted only by assuming that, contrary to AOT systems, the water molecules are entrapped at the interfaces without coalescing into an inner water pool. Also, the charge transport mechanisms look very different in the two kinds of systems. In particular, in the case of lecithin, it is shown how the conductivity appears mainly due to inter-micellar bond percolation: it is suggested that the solvated water molecules can induce a change of the surface curvature, in such a way promoting the formation of branch points. The idea of the existence of a percolated network of branched cylindrical micelles agrees with the observed temperature dependence of the system conductivity. The study of the electrorheologic behavior of the system under electric field confirms the existence of a percolated transient network in the gel phase.

  3. Local Mechanical Fields in Interface Percolated Nanocomposites

    NASA Astrophysics Data System (ADS)

    Burrows, Brian James

    Polymer nanocomposites can enable the innovative design of multi-functional materials. Metallic fillers in polymer matrices can exhibit improved electronic properties at low volume fractions while maintaining the low density, transparency, and easy processing of polymers. Surprisingly, mechanical properties also show enhancement at these uncharacteristically low volume fractions. Two mechanisms have been suggested as contributing to this enhancement. The first is the formation of a percolated microstructure; the second is the significant influence of the interface region between the matrix and filler. The majority of mathematical models describing this novel mechanical behavior are based on percolation models, which only consider microstructural connectivity. Changes in mechanical properties are likely to be affected by complex microstructures, beyond the simply connected, as well as by micromechanical mechanisms associated with these microstructures. These more complex microstructures and mechanisms may be challenging to identify and describe. In this work the underlying mechanical mechanisms are investigated using a probabilistic and statistical characterization of local strain fields. These continuous fields are more amenable to statistical characterization than the spatial ternary (matrix, particle and interface) fields that describe the microstructure. An apparent percolation threshold is identified based on statistical characterization of the elastic moduli, distributions of local strains and spatial autocorrelation of local strain fields. The statistics of strain fields associated with microstructures producing minimum and maximum moduli are also compared.

  4. Recycling of Reinforced Plastics

    NASA Astrophysics Data System (ADS)

    Adams, R. D.; Collins, Andrew; Cooper, Duncan; Wingfield-Digby, Mark; Watts-Farmer, Archibald; Laurence, Anna; Patel, Kayur; Stevens, Mark; Watkins, Rhodri

    2014-02-01

    This work has shown is that it is possible to recycle continuous and short fibre reinforced thermosetting resins while keeping almost the whole of the original material, both fibres and matrix, within the recyclate. By splitting, crushing hot or cold, and hot forming, it is possible to create a recyclable material, which we designate a Remat, which can then be used to remanufacture other shapes, examples of plates and tubes being demonstrated. Not only can remanufacturing be done, but it has been shown that over 50 % of the original mechanical properties, such as the E modulus, tensile strength, and interlaminar shear strength, can be retained. Four different forms of composite were investigated, a random mat Glass Fibre Reinforced Plastic (GFRP) bathroom component and boat hull, woven glass and carbon fibre cloth impregnated with an epoxy resin, and unidirectional carbon fibre pre-preg. One of the main factors found to affect composite recyclability was the type of resin matrix used in the composite. Thermoset resins tested were shown to have a temperature range around the Glass Transition Temperature (Tg) where they exhibit ductile behaviour, hence aiding reforming of the material. The high-grade carbon fibre prepreg was found to be less easy to recycle than the woven of random fibre laminates. One method of remanufacturing was by heating the Remat to above its glass transition temperature, bending it to shape, and then cooling it. However, unless precautions are taken, the geometric form may revert. This does not happen with the crushed material.

  5. Recycling in a megacity.

    PubMed

    Themelis, Nickolas J; Todd, Claire E

    2004-04-01

    In the aftermath of the 9/11 disaster, Mayor Bloomberg of New York City unveiled an aggressive budget plan that included the temporary suspension of glass and plastics recycling. This was considered by many to be anti-environmental, but the results of this study show that for lack of markets, even at zero or negative prices, nearly 90% of the plastic and glass set aside by thoughtful New Yorkers was transported to materials recovery facilities (MRFs) and from there to landfills. Sending bales of plastics to landfills is not limited to New York City. It is an environmental paradox that the United States is digging up new oil fields in pristine areas and, at the same time, continues to convert greenfields to brownfields by burying nearly 20 million tons of plastic fuel annually. The study also determined that at the present rate of source separation, estimated to be less than 30% of the available recyclables in 1999, building large, modern MRFs may increase substantially the rate of New York City recycling and also allow single-stream collection of commingled recyclables, as is done in Phoenix, AZ. Single-stream collection simplifies separation at the source by citizens and increases the amount of collected recyclables. Also, because collection represents a large fraction of the costs of waste management, it may have a significant economic advantage. PMID:15115367

  6. Percolation in a Proton Exchange Membrane Fuel Cell Catalyst Layer

    SciTech Connect

    Stacy, Stephen; Allen, Jeffrey

    2012-07-01

    Water management in the catalyst layers of proton exchange membrane fuel cells (PEMFC) is confronted by two issues, flooding and dry out, both of which result in improper functioning of the fuel cell and lead to poor performance and degradation. At the present time, the data that has been reported about water percolation and wettability within a fuel cell catalyst layer is limited. A method and apparatus for measuring the percolation pressure in the catalyst layer has been developed based upon an experimental apparatus used to test water percolation in porous transport layers (PTL). The experimental setup uses a pseudo Hele-Shaw type testing where samples are compressed and a fluid is injected into the sample. Testing the samples gives percolation pressure plots which show trends in increasing percolation pressure with an increase in flow rate. A decrease in pressure was seen as percolation occurred in one sample, however the pressure only had a rising effect in the other sample.

  7. Continuum percolation of carbon nanotubes in polymeric and colloidal media

    PubMed Central

    Kyrylyuk, Andriy V.; van der Schoot, Paul

    2008-01-01

    We apply continuum connectedness percolation theory to realistic carbon nanotube systems and predict how bending flexibility, length polydispersity, and attractive interactions between them influence the percolation threshold, demonstrating that it can be used as a predictive tool for designing nanotube-based composite materials. We argue that the host matrix in which the nanotubes are dispersed controls this threshold through the interactions it induces between them during processing and through the degree of connectedness that must be set by the tunneling distance of electrons, at least in the context of conductivity percolation. This provides routes to manipulate the percolation threshold and the level of conductivity in the final product. We find that the percolation threshold of carbon nanotubes is very sensitive to the degree of connectedness, to the presence of small quantities of longer rods, and to very weak attractive interactions between them. Bending flexibility or tortuosity, on the other hand, has only a fairly weak impact on the percolation threshold. PMID:18550818

  8. Scrap tire recycling

    SciTech Connect

    Lula, J.W.; Bohnert, G.W.

    1997-03-01

    As the automobile tire technology has grown and met the need for safer and more durable tires, stronger reinforcement and more chemically resistant rubber compounds have made recycling tires more difficult. In an effort to resolve this problem, techniques and equipment were developed to grind tires into small pieces, and new markets were sought to utilize the crumb rubber product streams from ground tires. Industrial combustion processes were modified to accept scrap tires as fuel. These efforts have been beneficial, steadily increasing the percentage of scrap tires recycled to about 10% in 1985, and reaching 72% in 1995. By the end of 1997, fully 100% of tires generated in the U.S. are expected to be recycled.

  9. Topology of a percolating soil pore network

    NASA Astrophysics Data System (ADS)

    Capa-Morocho, M.; Ruiz-Ramos, M.; Hapca, S. M.; Houston, A.; Tarquis, A. M.

    2012-04-01

    A connectivity function defined by the 3D-Euler number, is a topological indicator and can be related to hydraulic properties (Vogel and Roth, 2001). This study aims to develop connectivity Euler indexes as indicators of the ability of soils for fluid percolation. The starting point was a 3D grey image acquired by X-ray computed tomography of a soil at bulk density of 1.2 mg cm-3. This image was used in the simulation of 40000 particles following a directed random walk algorithms with 7 binarization thresholds. These data consisted of 7 files containing the simulated end points of the 40000 random walks, obtained in Ruiz-Ramos et al. (2010). MATLAB software was used for computing the frequency matrix of the number of particles arriving at every end point of the random walks and their 3D representation. In a former work (Capa et al., 2011) a criteria for choosing the optimal threshold of grey value was identified: Final positions were divided in two subgroups, cg1 (positions with frequency of the number of particles received greater than the median) and cg2 (frequency lower or equal to median). Images with maximum difference between the Z coordinate of the center of gravity of both subgroups were selected as those with optimal threshold that reflects the major internal differences in soil structure that are relevant to percolation. According to this criterion, the optimal threshold for the soil with density 1.2 mg cm-3 was 24.Thresholds above and below the optimal (23 and 25) were also considered to confirm this selection; therefore the analysis were conducted for three files (1 image with 3 grey threshold values, which have different porosity). Additionally, three random matrix simulations with the same porosity than the selected binaries images were used to test the existence of pore connectivity as a consequence of a non-random soil structure. Therefore, 6 matrix were considered (three structured and three random) for this study. Random matrix presented a normal distribution of percolation speed contrary to the simulated percolation speed for structured soil images. For all of them, Minkowski functionals were calculated applying Ohser and Mucklich (2001) methodology. Interpretation of results in terms of soil percolation behavior of these soils will be derived.

  10. Correction-to-scaling exponent for two-dimensional percolation

    SciTech Connect

    Ziff, Robert M. [Center for the Study of Complex Systems and Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2011-02-15

    We show that the correction-to-scaling exponents in two-dimensional percolation are bounded by {Omega}{<=}72/91, {omega}=D{Omega}{<=}3/2, and {Delta}{sub 1}={nu}{omega}{<=}2, based upon Cardy's result for the crossing probability on an annulus. The upper bounds are consistent with many previous measurements of site percolation on square and triangular lattices and new measurements for bond percolation, suggesting that they are exact. They also agree with exponents for hulls proposed recently by Aharony and Asikainen, based upon results of den Nijs. A corrections scaling form evidently applicable to site percolation is also found.

  11. Recycling of pavement materials

    E-print Network

    O'Neal, Randy Jim

    1976-01-01

    was recycled. Mixing was accom- plished by using a 10-by $0-foot drum mixer with a low efficiency wet wash. This mixer had an asphalt line in- side the drum and introduced $. 5 percent asphalt by weight into the old pavement which contained. ). 7 percent... material from old asphalt pavement and coarse aggregate. One and one- half percent emulsion was added. Air pollution seemed to be the biggest problem. Warren Brothers feel that the main objective of recycling is to utilize existing plants with minor...

  12. Recycle of battery components

    NASA Astrophysics Data System (ADS)

    Pemsler, J. P.; Spitz, R. A.

    The recycle disposal scenario for the batteries nickel/zinc, nickel/iron, zinc/chlorine, zinc/bromine, sodium/sulfur and lithium-aluminum/metal sulfide was considered. Flowsheets are presented which include disassembly, materials handling, melting or solubization, liquid/solid separations, purifications and waste handling. Material and energy balances are provided for all major streams and capital and operating costs for typical plant sizes are presented. Recycle is a a viable option in all cases. Recommendations are made for the best process options and for additional studies on the sodium/sulfur and lithium-aluminum/metal sulfide batteries.

  13. Recycled Aluminum Ornaments

    NSDL National Science Digital Library

    Wishart, Ray

    This lesson plan from ATEEC will explain the principles of recycling. The activity would be most appropriate for technology studies or high school science classes. In all, it would require 2-5 hours of class time to complete. The purpose of the lesson is to demonstrate how aluminum is recycled. This laboratory activity does require some special equipment including a heat source capable of melting aluminum and an outdoor work area. Extension activities are also provided. The lesson plan is available for download as a PDF; users must create a free, quick login with ATEEC to access the materials.

  14. Recycling of tantalum

    SciTech Connect

    Hoppe, A. [H.C. Starck GmbH and Co. KG, Goslar (Germany); Korinek, G.J. [Tantalum-Niobium International Study Center, Brussels (Belgium)

    1995-12-31

    Although tantalum is not usually regarded as a precious metal, its pricing structure is very similar to that of silver. Different from precious metals, tantalum has only industrial applications and its use is about 1,000 metric tons per year. The intrinsic value of tantalum already was a driving force for its recycling. Based on these facts the tantalum industry world-wide is approaching the closed-loop concept of its recycling. A detailed material flow of tantalum processing as well as recovery of residues and used products will be discussed.

  15. Recycled Unbound Base Pooled Fund Study

    E-print Network

    Minnesota, University of

    Recycled Unbound Base Pooled Fund Study Tuncer B. Edil Recycled Materials Resource Center Geological Engineering Program University of Wisconsin-Madison #12;·! Recycled Concrete Aggregate (RCA absorption ­! Un-Hydrated cement increases strength and durability ·! Recycled asphalt pavement (RAP

  16. Power recycling for an interferometric gravitational wave

    E-print Network

    Ejiri, Shinji

    THESIS Power recycling for an interferometric gravitational wave detector Masaki Ando Department . . . . . . . . . . . . . . 48 3.3 Power recycling . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 3.3.1 Principle of power recycling . . . . . . . . . . . . . . . . . 50 3.3.2 Recycling cavity

  17. Fiber-Optic Ammonia Sensors

    NASA Technical Reports Server (NTRS)

    Carter, Michael T.

    2003-01-01

    Reversible, colorimetric fiber-optic sensors are undergoing development for use in measuring concentrations of ammonia in air at levels relevant to human health [0 to 50 parts per million (ppm)]. A sensor of this type includes an optical fiber that has been modified by replacing a portion of its cladding with a polymer coat that contains a dye that reacts reversibly with ammonia and changes color when it does so. The change in color is measured as a change in the amount of light transmitted from one end of the fiber to the other. Responses are reversible and proportional to the concentration of ammonia over the range from 9 to 175 ppm and in some cases the range of reversibility extends up to 270 ppm. The characteristic time for the response of a sensor to rise from 10 to 90 percent of full scale is about 25 seconds. These sensors are fully operational in pure carbon dioxide and are not adversely affected by humidity. This work was done by Michael T. Carter

  18. PITT RECYCLES! *Please empty cans!

    E-print Network

    Sibille, Etienne

    PITT RECYCLES! Steel Aluminum Tin cans *Please empty cans! *Please empty containers! *Plastic bags can be recycled at Giant Eagle and Trader Joe's. Look on the bottom or the side of the container NOT Recyclable... Food waste Lunch bags Coffee cups Cellophane Tissues Paper towels Carbon paper Styrofoam Metals

  19. Recycling incineration: Evaluating the choices

    Microsoft Academic Search

    R. A. Denison; J. Ruston

    1993-01-01

    Conflicts between proponents of municipal solid waste incineration and advocates of recycling have escalated with efforts to reduce the volume of waste that ends up in landfills. Central to this debate is competition for materials that are both combustible and recyclable. Environmental and economic concerns also play a major role. This book, produced by the Environmental Defense Fund, compares recycling

  20. An Overview of Plastics Recycling

    Microsoft Academic Search

    Jack Milgrom

    1982-01-01

    In 1980, plastic in the United States has overtaken steel on a volume basis as the dominant material. Though recycling of iron and steel goes back to the early years of United States history, plastics recycling is in its infancy. Today, plastics recycling is an urgent necessity as petrochemical raw materials, energy, and disposal become more costly.

  1. CHERRY: CHECKPOINTED EARLY RESOURCE RECYCLING

    E-print Network

    Torrellas, Josep

    1 2 3 CHERRY: CHECKPOINTED EARLY RESOURCE RECYCLING Jos´e F. Mart´inez1 , Jose Renau2 Michael C. Huang3 , Milos Prvulovic2 , and Josep Torrellas2 #12;Cherry: Checkpointed Early Resource Recycling efficient use by aggressive recycling Opportunity: Resources reserved until retirement § ¦ ¤ ¥ Solution

  2. Recycling Behavior: A Multidimensional Approach

    ERIC Educational Resources Information Center

    Meneses, Gonzalo Diaz; Palacio, Asuncion Beerli

    2005-01-01

    This work centers on the study of consumer recycling roles to examine the sociodemographic and psychographic profile of the distribution of recycling tasks and roles within the household. With this aim in mind, an empirical work was carried out, the results of which suggest that recycling behavior is multidimensional and comprises the undertaking…

  3. Recycling in a Megacity

    Microsoft Academic Search

    Nickolas J. Themelis; Claire E. Todd

    2004-01-01

    In the aftermath of the 9\\/11 disaster, Mayor Bloomberg of New York City unveiled an aggressive budget plan that included the temporary suspension of glass and plastics recycling. This was considered by many to be anti-environmental, but the results of this study show that for lack of markets, even at zero or negative prices, nearly 90% of the plastic and

  4. WRAMS, sustainable water recycling

    Microsoft Academic Search

    H. Chapman

    2006-01-01

    The Water Reclamation and Management Scheme (WRAMS) at Sydney Olympic Park was built as part of the Olympic Games in 2000. The Scheme was designed to treat raw domestic sewage into recycled water which is then sold back to consumers. The main elements of WRAMS are a water reclamation plant, a water treatment plant, storm water collection, clean water storage

  5. Recycling and Restoration

    NSDL National Science Digital Library

    KET

    2011-01-11

    This video explains how Bernheim Arboretum and Research Forest near Louisville, Kentucky used recycled cypress from pickle vats to build its visitor center and then “paid back” nature by creating a cypress-tupelo swamp at one end of a lake on the park grounds.

  6. National policy toward recycling

    Microsoft Academic Search

    James. Boyd

    1976-01-01

    Efforts and recommendations of the National Commission on Materials Policy are reviewed. The materials recovery and reuse recommendations appear to have received the most attention. The principal conservation potential lies in energy savings associated with the production of aluminum, steel and paper from secondary materials. Conservation also involves avoiding pollution. The success of recycling depends upon the ability to process

  7. Recycled Insect Models

    ERIC Educational Resources Information Center

    Rule, Audrey C.; Meyer, Mary Ann

    2007-01-01

    This article presents an engaging activity in which high school students use a dichotomous key to guide the creation and classification of model insects from recycled plastic lids and containers. Besides teaching the use of a dichotomous key and the effect of evolutionary descent upon groupings of organisms, this activity focuses on an…

  8. Fuels from Recycling Systems

    ERIC Educational Resources Information Center

    Tillman, David A.

    1975-01-01

    Three systems, operating at sufficient scale, produce fuels that may be alternatives to oil and gas. These three recycling systems are: Black Clawson Fiberclaim, Franklin, Ohio; Union Carbide, South Charleston, West Virginia; and Union Electric, St. Louis, Missouri. These produce a wet fuel, a pyrolytic gas, and a dry fuel, respectively. (BT)

  9. Recycling Study Guide.

    ERIC Educational Resources Information Center

    Hallowell, Anne; And Others

    This study guide was designed to help teachers and students understand the problems surrounding solid wastes. It includes an overview of solid waste and recycling, a glossary, suggested activities and a list of resource publications, audiovisual materials and organizations. There are 19 activity suggestions included in this guide designed for use…

  10. The Recycle Team.

    ERIC Educational Resources Information Center

    Scott, Roger; And Others

    This guide provides lessons that enable students to learn how important it is for each of us to take care of the environment by minimizing the problems caused by too much trash. In the 10 lessons included here, students and their families learn how they can be part of the solution by practicing source reduction and by reusing, recycling, and…

  11. Reduce, Reuse, and Recycle

    NSDL National Science Digital Library

    Nicole

    2008-11-19

    Boys and girls, grab your nose-plugs because today we are going to be digging through some garbage! We use a lot of garbage; the average American throws away nearly four pounds everyday. That\\'s a whopping 1,600 pounds a year! That means that every year, EACH one of you toss enough trash to equal the weight of all the students in our class...COMBINED! That\\'s a lot of garbage. Our world is big, but you might not have realized just how small it really is when it comes to holding all this trash. Would you want garbage in your backyard? Your playground? The park? There\\'s only so many places to store our waste. So, what do we do? We RECYCLE! What Does It Mean To Recycle? Recycling is taking things we use and would normally through into the trash can and putting them in a separate container. Instead of going to the dump, it goes to a recycling plant. Things like paper, newspaper, cardboard, plastic, glass, and aluminum are all products ...

  12. Scrap tire recycling

    Microsoft Academic Search

    J. W. Lula; G. W. Bohnert

    1997-01-01

    As the automobile tire technology has grown and met the need for safer and more durable tires, stronger reinforcement and more chemically resistant rubber compounds have made recycling tires more difficult. In an effort to resolve this problem, techniques and equipment were developed to grind tires into small pieces, and new markets were sought to utilize the crumb rubber product

  13. Computer Recycling Farm USA

    USGS Multimedia Gallery

    USGS conducted a study of plastic pollution at this rural US site in the Midwest.  The recycler was receiving computers from companies at a rate which greatly exceeded the capacity of the operation.  Approximately 50,000 computers remained outdoors on 15 acres for nearly a decade.  The site has sinc...

  14. COMPOSITES FROM RECYCLED MATERIALS

    Microsoft Academic Search

    ROGER M. ROWELL; JOHN A. YOUNGQUIST

    A reduction is urgently needed in the quan- tities of industrial and municipal solid waste materials that are being landfilled currently. Major components of municipal solid waste include waste wood, paper. plastics. fly ash. gypsum. and other biomass fibers -- materials that offer great opportunities as recycled ingre- dients in wood composites. This paper dis- cusses possibilities for manufacturing selected

  15. Helium-Recycling Plant

    NASA Technical Reports Server (NTRS)

    Cook, Joseph

    1996-01-01

    Proposed system recovers and stores helium gas for reuse. Maintains helium at 99.99-percent purity, preventing water vapor from atmosphere or lubricating oil from pumps from contaminating gas. System takes in gas at nearly constant low back pressure near atmospheric pressure; introduces little or no back pressure into source of helium. Concept also extended to recycling of other gases.

  16. RECYCLABILITY INDEX FOR AUTOMOBILES

    EPA Science Inventory

    The project's purpose is to create a rating system for the ecological impacts of vehicles at the end of their life based on recyclability, toxic material content, and ultimate disposal. Each year, 10-11 million vehicles are retired from service in the United States. The vehi...

  17. Recycle Your Own Paper!

    NSDL National Science Digital Library

    Twin Cities Public Television, Inc.

    2007-01-01

    In this activity (page 2 of PDF), learners will prepare sheets of homemade recycled paper from several different source pulps. Once dry, each sample will be drawn on with a marker to test how far ink spreads in the fibers of the different kinds of papers. Relates to the linked video, DragonflyTV GPS: Garbology.

  18. Refrigerator recycling and CFCs

    SciTech Connect

    Shepard, M.; Hawthorne, W.; Wilson, A.

    1994-12-31

    Utility-sponsored refrigerator and freezer pick-up programs have removed almost 900,000 inefficient appliances from the North American electric grid to date. While the CFC-12 refrigerant from the discarded appliances is typically removed and recycled, in all but a few programs the CFC-11 in the foam insulation is not. About a quarter-billion pounds of CFC-11 are banked in refrigerator foam in the United States. Release of this ``bank`` of CFC, combined with that from foam insulation used in buildings, will be the largest source of future emissions if preventive measures are not taken. Methods exist to recover the CFC for reuse or to destroy it by incineration. The task of recycling or destroying the CFCs and other materials from millions of refrigerators is a daunting challenge, but one in which utilities can play a leadership role. E Source believes that utilities can profitably serve as the catalyst for public-private partnerships that deliver comprehensive refrigerator recycling. Rather than treating such efforts solely as a DSM resource acquisition, utilities could position these programs as a multifaceted service delivery that offers convenient appliance removal for homeowners, a solid waste minimization service for landfills, a source of recycled materials for industry, and a CFC recovery and/or disposal service in support of the HVAC industry and society`s atmospheric protection goals and laws. Financial mechanisms could be developed through these public-private enterprises to ensure that utilities are compensated for the extra cost of fully recycling refrigerators, including the foam CFC.

  19. Analysis of Ammonia Toxicity in Landfill Leachates

    PubMed Central

    Osada, Takuya; Nemoto, Keisuke; Nakanishi, Hiroki; Hatano, Ayumi; Shoji, Ryo; Naruoka, Tomohiro; Yamada, Masato

    2011-01-01

    Toxicity identification evaluation (TIE) phase I manipulations and toxicity test with D. magna were conducted on leachates from an industrial waste landfill site in Japan. Physicochemical analysis detected heavy metals at concentrations insufficient to account for the observed acute toxicity. The graduated pH and aeration manipulations identified the prominent toxicity of ammonia. Based on joint toxicity with additive effects of unionized ammonia and ammonium ions, the unionized ammonia toxicity (LC50,NH3(aq)) was calculated as 3.3?ppm, and the toxicity of ammonium ions (LC50,NH4+) was calculated as 222?ppm. Then, the contribution of ammonia toxicity in the landfill leachate toxicity was calculated as 58.7?vol% of the total toxicity in the landfill leachate. Other specific toxicants masked by ammonia's toxicity were detected. Contribution rate of the toxicants other than by ammonia was 41.3?vol% of the total toxicity of the landfill leachate. PMID:23724289

  20. Thermodynamic Properties of Aqueous Solution of Ammonia

    NASA Astrophysics Data System (ADS)

    Kitamura, Hiroshi; Oguchi, Kosei

    Present status on the thermodynamic properties of experimental data and their correlations of both ammonia and aqueous solution of ammonia was introduced in this paper. The aqueous solution of ammonia is used for not only a working fluid in absorption refrigerator cycles but also working fluids in bottoming cycles of steam power plants and other heat recovering systems. Therefore, the thermodynamic properties of this substance are required in a wide range of temperatures, pressures and compositions. The experimental results of pVTx properties for ammonia and aqueous solution of ammonia and their comparisons with a formulation by Tillner-Roth and Friend1) were critically surveyed. The “Guideline on the IAPWS Formulation 2000 for the Thermodynamic Properties of Ammonia-Water Mixtures”, correlated by Tillner-Roth and Friend1), was approved on September, 2001, by the International Association for the Properties of Water and Steam (IAPWS) 2).

  1. Reversible intercalation of ammonia molecules into a layered double hydroxide structure without exchanging nitrate counter-ions

    SciTech Connect

    Carbajal Arizaga, Gregorio Guadalupe, E-mail: gregoriocarbajal@yahoo.com.m [Universidad Nacional Autonoma de Mexico, Centro de Nanociencias y Nanotecnologia, Km. 107 Carretera Tijuana-Ensenada, Apdo. Postal 14, C.P. 22800. Ensenada, Baja California (Mexico); Wypych, Fernando [CEPESQ-Research Centre of Applied Chemistry, Department of Chemistry, Federal University of Parana, P.O. Box 19081, 81531-980 Curitiba, PR (Brazil); Castillon Barraza, Felipe; Contreras Lopez, Oscar Edel [Universidad Nacional Autonoma de Mexico, Centro de Nanociencias y Nanotecnologia, Km. 107 Carretera Tijuana-Ensenada, Apdo. Postal 14, C.P. 22800. Ensenada, Baja California (Mexico)

    2010-10-15

    A zinc/aluminum LDH was precipitated with recycled ammonia from a chemical vapor deposition reaction. The LDH presented a crystalline phase with basal distance of 8.9 A, typical for nitrate-containing LDHs, and another phase with a basal distance of 13.9 A. Thermal treatment at 150 {sup o}C eliminated the phase with the bigger basal distance leaving only the anhydrous nitrate-intercalated LDH structure with 8.9 A. Intense N-H stretching modes in the FTIR spectra suggested that the expansion was due to intercalation of ammonia in the form of [NH{sub 4}(NH{sub 3}){sub n}]{sup +} species. When additional samples were precipitated with pure ammonia, the conventional LDH nitrate structure was obtained (8.9 A basal distance) at pH=7, as well as a pure crystalline phase with 13.9 A basal distance at pH=10 due to ammonia intercalation that can be removed by heating at 150 {sup o}C or by stirring in acetone, confirming a unusual sensu stricto intercalation process into a LDH without exchanging nitrate ions. - Graphical abstract: LDH-nitrate precipitated with ammonia expands the interlayer space if ammonia is bubbled up to pH 10. The basal distance decreased when the compound was heated at 150 {sup o}C or stirred in acetone. Nitrate ions are not exchanged.

  2. Percolation of interdependent networks with intersimilarity

    NASA Astrophysics Data System (ADS)

    Hu, Yanqing; Zhou, Dong; Zhang, Rui; Han, Zhangang; Rozenblat, Céline; Havlin, Shlomo

    2013-11-01

    Real data show that interdependent networks usually involve intersimilarity. Intersimilarity means that a pair of interdependent nodes have neighbors in both networks that are also interdependent [Parshani Europhys. Lett.EULEEJ0295-507510.1209/0295-5075/92/68002 92, 68002 (2010)]. For example, the coupled worldwide port network and the global airport network are intersimilar since many pairs of linked nodes (neighboring cities), by direct flights and direct shipping lines, exist in both networks. Nodes in both networks in the same city are regarded as interdependent. If two neighboring nodes in one network depend on neighboring nodes in the other network, we call these links common links. The fraction of common links in the system is a measure of intersimilarity. Previous simulation results of Parshani suggest that intersimilarity has considerable effects on reducing the cascading failures; however, a theoretical understanding of this effect on the cascading process is currently missing. Here we map the cascading process with intersimilarity to a percolation of networks composed of components of common links and noncommon links. This transforms the percolation of intersimilar system to a regular percolation on a series of subnetworks, which can be solved analytically. We apply our analysis to the case where the network of common links is an Erd?s-Rényi (ER) network with the average degree K, and the two networks of noncommon links are also ER networks. We show for a fully coupled pair of ER networks, that for any K?0, although the cascade is reduced with increasing K, the phase transition is still discontinuous. Our analysis can be generalized to any kind of interdependent random network systems.

  3. Percolation of interdependent networks with intersimilarity.

    PubMed

    Hu, Yanqing; Zhou, Dong; Zhang, Rui; Han, Zhangang; Rozenblat, Céline; Havlin, Shlomo

    2013-11-01

    Real data show that interdependent networks usually involve intersimilarity. Intersimilarity means that a pair of interdependent nodes have neighbors in both networks that are also interdependent [Parshani et al. Europhys. Lett. 92, 68002 (2010)]. For example, the coupled worldwide port network and the global airport network are intersimilar since many pairs of linked nodes (neighboring cities), by direct flights and direct shipping lines, exist in both networks. Nodes in both networks in the same city are regarded as interdependent. If two neighboring nodes in one network depend on neighboring nodes in the other network, we call these links common links. The fraction of common links in the system is a measure of intersimilarity. Previous simulation results of Parshani et al. suggest that intersimilarity has considerable effects on reducing the cascading failures; however, a theoretical understanding of this effect on the cascading process is currently missing. Here we map the cascading process with intersimilarity to a percolation of networks composed of components of common links and noncommon links. This transforms the percolation of intersimilar system to a regular percolation on a series of subnetworks, which can be solved analytically. We apply our analysis to the case where the network of common links is an Erd?s-Rényi (ER) network with the average degree K, and the two networks of noncommon links are also ER networks. We show for a fully coupled pair of ER networks, that for any K?0, although the cascade is reduced with increasing K, the phase transition is still discontinuous. Our analysis can be generalized to any kind of interdependent random network systems. PMID:24329316

  4. Percolation in multiplex networks with overlap

    NASA Astrophysics Data System (ADS)

    Cellai, Davide; López, Eduardo; Zhou, Jie; Gleeson, James P.; Bianconi, Ginestra

    2013-11-01

    From transportation networks to complex infrastructures, and to social and communication networks, a large variety of systems can be described in terms of multiplexes formed by a set of nodes interacting through different networks (layers). Multiplexes may display an increased fragility with respect to the single layers that constitute them. However, so far the overlap of the links in different layers has been mostly neglected, despite the fact that it is an ubiquitous phenomenon in most multiplexes. Here, we show that the overlap among layers can improve the robustness of interdependent multiplex systems and change the critical behavior of the percolation phase transition in a complex way.

  5. Modied invasion percolation model for fracking

    NASA Astrophysics Data System (ADS)

    Norris, J.; Turcotte, D. L.; Rundle, J. B.

    2013-12-01

    Recent developments in hydraulic fracturing (fracking) have enabled the recovery of large reserves of natural gas and oil. These developments include a change from low-volume, high-viscosity fluid injection to high-volume, low-viscosity injection. We consider new models of Invasion Percolation, (IP) which are models that were originally introduced to represent the injection of an invading fluid into a fluid filled porous medium. A primary difference between our model and the original model is the elimination of any unbroken bonds whose end sites are both filled with fluid. While the original model was found to have statistics nearly identical to traditional percolation, we find significant statistical differences. In particular, the distribution of broken bond strengths displays a strong roll-over near the critical point. Another difference between traditional percolation clusters and clusters generated using our model is the absence of internal loops. The modified growth rule prevents the formation of internal loops making the growing cluster ramified. Other ramified networks include drainage basins and DLA clusters. The study of drainage basins led to the development of Horton-Strahler and Tokunaga network statistics. We used both Horton-Strahler and Tokunaga network statistics to characterize simulated clusters using and found that the clusters generated by our model are statistically self-similar fractals. In addition to fractal clusters, IP also displays burst dynamics, in which the cluster extends rapidly through a spontaneous extension of percolating bonds. We define a burst to be a consecutive series of broken bonds whose strengths are all below a specified value. Using this definition of bursts we found good agreement with a power-law frequency-area distribution. Our model displays many of the characteristics of an energy landscape, and shows many similarities to DLA, neural networks, ecological landscapes, and the world wide web. We anticipate that this new class of models will have broad applicability to the study of instabilities in high dimensional complex networks, a topic of considerable interest across a wide array of fields.

  6. Directed Last Passage Percolation with Discontinuous Weights

    NASA Astrophysics Data System (ADS)

    Calder, Jeff

    2015-02-01

    We prove that a directed last passage percolation model with discontinuous macroscopic (non-random) inhomogeneities has a continuum limit that corresponds to solving a Hamilton-Jacobi equation in the viscosity sense. This Hamilton-Jacobi equation is closely related to the conservation law for the hydrodynamic limit of the totally asymmetric simple exclusion process. We also prove convergence of a numerical scheme for the Hamilton-Jacobi equation and present an algorithm based on dynamic programming for finding the asymptotic shapes of maximal directed paths.

  7. Percolation Crossing Formulas and Conformal Field Theory

    E-print Network

    Jacob J. H. Simmons; Peter Kleban; Robert M. Ziff

    2007-06-03

    Using conformal field theory, we derive several new crossing formulas at the two-dimensional percolation point. High-precision simulation confirms these results. Integrating them gives a unified derivation of Cardy's formula for the horizontal crossing probability $\\Pi_h(r)$, Watts' formula for the horizontal-vertical crossing probability $\\Pi_{hv}(r)$, and Cardy's formula for the expected number of clusters crossing horizontally $\\mathcal{N}_h(r)$. The main step in our approach implies the identification of the derivative of one primary operator with another. We present operator identities that support this idea and suggest the presence of additional symmetry in $c=0$ conformal field theories.

  8. Percolation in multiplex networks with overlap.

    PubMed

    Cellai, Davide; López, Eduardo; Zhou, Jie; Gleeson, James P; Bianconi, Ginestra

    2013-11-01

    From transportation networks to complex infrastructures, and to social and communication networks, a large variety of systems can be described in terms of multiplexes formed by a set of nodes interacting through different networks (layers). Multiplexes may display an increased fragility with respect to the single layers that constitute them. However, so far the overlap of the links in different layers has been mostly neglected, despite the fact that it is an ubiquitous phenomenon in most multiplexes. Here, we show that the overlap among layers can improve the robustness of interdependent multiplex systems and change the critical behavior of the percolation phase transition in a complex way. PMID:24329322

  9. Directed last passage percolation with discontinuous weights

    E-print Network

    Jeff Calder

    2014-12-13

    We prove that a directed last passage percolation model with discontinuous macroscopic (non-random) inhomogeneities has a continuum limit that corresponds to solving a Hamilton-Jacobi equation in the viscosity sense. This Hamilton-Jacobi equation is closely related to the conservation law for the hydrodynamic limit of the totally asymmetric simple exclusion process. We also prove convergence of a numerical scheme for the Hamilton-Jacobi equation and present an algorithm based on dynamic programming for finding the asymptotic shapes of maximal directed paths.

  10. Percolation model of ionic channel dynamics.

    PubMed Central

    Doster, W; Schirmacher, W; Settles, M

    1990-01-01

    The nonexponential closed-time distributions observed for ionic channels have been explained recently by quasi-one-dimensional models of structural diffusion (Millhauser, G. L., E. E. Salpeter, and R. E. Oswald. 1988. Proc. Natl. Acad. Sci. USA. 85: 1503-1507; Condat, C. A., and J. Jäckle. 1989. Biophys. J. 55: 915-925; Levitt, D. G. 1989. Biophys. J. 55: 489-498). We generalize this treatment by allowing for more complex trajectories using percolation theory. We assume that the gating transition depends on marginally connected conformational states leading to the observed spread in time scales. PMID:1689594

  11. Polyaniline-based optical ammonia detector

    DOEpatents

    Duan, Yixiang (Los Alamos, NM); Jin, Zhe (Los Alamos, NM); Su, Yongxuan (Los Alamos, NM)

    2002-01-01

    Electronic absorption spectroscopy of a polyaniline film deposited on a polyethylene surface by chemical oxidation of aniline monomer at room temperature was used to quantitatively detect ammonia gas. The present optical ammonia gas detector was found to have a response time of less than 15 s, a regeneration time of less than 2 min. at room temperature, and a detection limit of 1 ppm (v/v) for ammonia, with a linear dynamic range from 180 ppm to 18,000 ppm.

  12. Ammonia Assimilation by Rhizobium Cultures and Bacteroids

    Microsoft Academic Search

    C. M. BROWN; M. J. DILWORTH

    1975-01-01

    SUMMARY The enzymes involved in the assimilation of ammonia by free-living cultures of Rhizobium spp. are glutamine synthetase (EC. 6.3. I. 2), glutamate synthase (L- glutamine : a-oxoglutarate amino transferase) and glutamate dehydrogenase (EC I.4. I.4). Under conditions of ammonia or nitrate limitation in a chemostat the assimilation of ammonia by cultures of R. leguminosarum, R. trifolii and R. japonicum

  13. Adsorption of ammonia on multilayer iron phthalocyanine

    SciTech Connect

    Isvoranu, Cristina; Knudsen, Jan; Ataman, Evren; Andersen, Jesper N.; Schnadt, Joachim [Division of Synchrotron Radiation Research, Department of Physics, Lund University, Box 118, 221 00 Lund (Sweden); Schulte, Karina [MAX-lab, Lund University, Box 118, 221 00 Lund (Sweden); Wang Bin; Bocquet, Marie-Laure [Laboratoire de chimie, Ecole normale superieure de Lyon, 46, Allee d'Italie, 69364 Lyon Cedex 07 (France)

    2011-03-21

    The adsorption of ammonia on multilayers of well-ordered, flat-lying iron phthalocyanine (FePc) molecules on a Au(111) support was investigated by x-ray photoelectron spectroscopy. We find that the electron-donating ammonia molecules coordinate to the metal centers of iron phthlalocyanine. The coordination of ammonia induces changes of the electronic structure of the iron phthalocyanine layer, which, in particular, lead to a modification of the FePc valence electron spin.

  14. Diplomarbeit in Physik Conformal Field Theory and Percolation

    E-print Network

    Flohr, Michael

    Diplomarbeit in Physik Conformal Field Theory and Percolation Annekathrin M bond percolation on an infinite square lattice at its critical point within a conformal field theory ansatz to solve the c 0 problem as well. 5 #12;Contents Introduction 8 Outline 10 1. Conformal Field

  15. Losses of Moisture and Plant Food By Percolation.

    E-print Network

    Fraps, G. S.

    1914-01-01

    . . . . . . . . . . . . . . . . . . . . . . . . 41 Nitrates from Manure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Percolation from Nitrates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Percolation of Potash... of 48 galvanized iron cans 12 inches in diameter and 24 inches deep, with a block tin tube at the bottom. These cans are buried in the ground. Figures 1 and 2 are drawn to scale, and show the an angement of the apparatus. The cans are connected...

  16. Percolation approach to phase transitions in high energy nuclear collisions

    E-print Network

    A. Rodrigues; R. Ugoccioni; J. Dias de Deus

    1998-12-15

    We study continuum percolation in nuclear collisions for the realistic case in which the nuclear matter distribution is not uniform over the collision volume, and show that the percolation threshold is increased compared to the standard, uniform situation. In terms of quark-gluon plasma formation this means that the phase transition threshold is pushed to higher energies.

  17. Planar percolation with a glimpse of SchrammLoewner Evolution

    E-print Network

    Paris-Sud XI, Université de

    . For general background on percolation, we refer the reader to the books of Grimmett [Gri99] and Kesten [Kes82 in the case of bond percolation on the square lattice by Kesten in [Kes80]. The proof can be summarized but satisfy equations: Kesten's scaling relations relate and to the so-called monochromatic one- arm

  18. Random walk on the infinite cluster of the percolation model

    Microsoft Academic Search

    G. R. Grimmett; H. Kesten; Y. Zhang

    1993-01-01

    Summary We consider random walk on the infinite cluster of bond percolation on Zd. We show that, in the supercritical regime whend?3, this random walk is a.s. transient. This conclusion is achieved by considering the infinite percolation cluster as a random electrical network in which each open edge has unit resistance. It is proved that the effective resistance of this

  19. REUSE AND RECYCLE OF BIO-RESIDUE (PERCOLATE) FROM CONSTRUCTED WETLAND TREATING SEPTAGE

    E-print Network

    Richner, Heinz

    CW treating septage could exhibit positive responses of the plant growth which increase seed yield. The experimental data of 3 crops plantation reviewed the plant available and total heavy metal concentrations were seed and oil content, it was found that the yields of sunflower and oil content from the 20

  20. Correlation effects in nanoparticle composites: Percolation, packing and tunneling

    NASA Astrophysics Data System (ADS)

    Mukherjee, Rupam

    Percolation is one of the most fundamental and far-reaching physical phenomena, with major implications in a vast variety of fields. The work described in this thesis aims to understand the role of percolation effects in various, seemingly unrelated phenomena, such as the dielectric permittivity of metal-insulator composites, tunneling percolation, and the relationship between percolation and filling factors. Specifically, we investigated 1) the very large enhancement of the dielectric permittivity of a composite metal -- insulator system, RuO2 - CaCu3Ti4O12 (CCTO) near the percolation threshold. For RuO2/CCTO composites, an increase in the real part of the dielectric permittivity (initially about 10 3-104 at 10 kHz) by approximately an order of magnitude is observed in the vicinity of the percolation threshold. 2) In the same system, apart from a classical percolation transition associated with the appearance of a continuous conductance path through RuO2 nanoparticles, at least two additional tunneling percolation transitions are detected. Such behavior is consistent with the recently emerged picture of a quantum conductivity staircase, which predicts several percolation tunneling thresholds in a system with a hierarchy of local tunneling conductance, due to various degrees of proximity of adjacent conducting particles distributed in an insulating matrix. 3) The filling factors of the composites of nanoparticles with different shapes have been studied as a function of volume fraction. Interestingly, like percolation, filling factors also obey critical power law behavior as a function of size ratio of constituent particles.

  1. Manifestation of percolation in high temperature superconductivity

    NASA Astrophysics Data System (ADS)

    Poccia, Nicola; Lankhorst, Martijn; Golubov, Alexander A.

    2014-08-01

    Emergent advanced electronic and magnetic functionalities in novel materials appear in systems with a complex lattice structure. The key point is understanding the intrinsic effect of lattice fluctuations on the relevant electronic features in the range of 10-100 meV near the Fermi level in new materials which is needed to develop advanced quantum nano-devices. This requires the control of structural inhomogeneity at multiple scales. Here we report some of the known advances in the field of percolative superconductivity. The necessity of the review is based on the growing consensus that the lack of an understanding of high temperature superconductivity is due to the few information on lattice fluctuations. In particular they could control the pseudo-gap phase, the electronic duality of holes in Fermi arcs and electrons in small Fermi pockets, multiple condensates in different points of the k-space. Moreover the emerging lattice granularity in cuprates shifts the search for the superconducting mechanism from a homogeneous superconductivity to a percolative superconductivity, therefore it is the scope of this review to provide further data to this kind of research.

  2. Percolation effect in thick film superconductors

    SciTech Connect

    Sali, R.; Harsanyi, G. [Technical Univ. of Budapest (Hungary)

    1994-12-31

    A thick film superconductor paste has been developed to study the properties of granulated superconductor materials, to observe the percolation effect and to confirm the theory of the conducting mechanism in the superconducting thick films. This paste was also applied to make a superconducting planar transformer. Due to high T{sub c} and advantageous current density properties the base of the paste was chosen to be of Bi(Pb)SrCaCuO system. For contacts a conventional Ag/Pt paste was used. The critical temperature of the samples were between 110 K and 115 K depending on the printed layer thickness. The critical current density at the boiling temperature of the liquid He- was between 200-300 A/cm{sup 2}. The R(T) and V(I) functions were measured with different parameters. The results of the measurements have confirmed the theory of conducting mechanism in the material. The percolation structure model has been built and described. As an application, a superconducting planar thick film transformer was planned and produced. Ten windings of the transformer were printed on one side of the alumina substrate and one winding was printed on the other side. The coupling between the two sides was possible through the substrate. The samples did not need special drying and firing parameters. After the preparation, the properties of the transformer were measured. The efficiency and the losses were determined. Finally, some fundamental advantages and problems of the process were discussed.

  3. k-Core percolation on multiplex networks

    E-print Network

    N. Azimi-Tafreshi; J. Gomez-Gardenes; S. N. Dorogovtsev

    2014-05-10

    We generalize the theory of k-core percolation on complex networks to k-core percolation on multiplex networks, where k=(k_a, k_b, ...). Multiplex networks can be defined as networks with a set of vertices but different types of edges, a, b, ..., representing different types of interactions. For such networks, the k-core is defined as the largest sub-graph in which each vertex has at least k_i edges of each type, i = a, b, ... . We derive self-consistency equations to obtain the birth points of the k-cores and their relative sizes for uncorrelated multiplex networks with an arbitrary degree distribution. To clarify our general results, we consider in detail multiplex networks with edges of two types, a and b, and solve the equations in the particular case of ER and scale-free multiplex networks. We find hybrid phase transitions at the emergence points of k-cores except the (1,1)-core for which the transition is continuous. We apply the k-core decomposition algorithm to air-transportation multiplex networks, composed of two layers, and obtain the size of (k_a, k_b)-cores.

  4. k-core percolation on multiplex networks.

    PubMed

    Azimi-Tafreshi, N; Gómez-Gardeñes, J; Dorogovtsev, S N

    2014-09-01

    We generalize the theory of k-core percolation on complex networks to k-core percolation on multiplex networks, where k?(k(1),k(2),...,k(M)). Multiplex networks can be defined as networks with vertices of one kind but M different types of edges, representing different types of interactions. For such networks, the k-core is defined as the largest subgraph in which each vertex has at least k(i) edges of each type, i=1,2,...,M. We derive self-consistency equations to obtain the birth points of the k-cores and their relative sizes for uncorrelated multiplex networks with an arbitrary degree distribution. To clarify our general results, we consider in detail multiplex networks with edges of two types and solve the equations in the particular case of Erd?s-Rényi and scale-free multiplex networks. We find hybrid phase transitions at the emergence points of k-cores except the (1,1)-core for which the transition is continuous. We apply the k-core decomposition algorithm to air-transportation multiplex networks, composed of two layers, and obtain the size of (k(1),k(2))-cores. PMID:25314490

  5. Composting to Recycle Biowaste

    Microsoft Academic Search

    György Füleky; Szilveszter Benedek

    \\u000a If agriculture is to be made sustainable, few activities like composting are very important. Composting not only allows organic\\u000a waste of agricultural origin to be recycled and returned to the soil, but also provides a solution for managing much of the\\u000a waste, which is currently a major problem. If urban organic waste is selectively collected and composted, it no longer

  6. COPPER CABLE RECYCLING TECHNOLOGY

    SciTech Connect

    Chelsea Hubbard

    2001-05-01

    The United States Department of Energy (DOE) continually seeks safer and more cost-effective technologies for use in deactivation and decommissioning (D&D) of nuclear facilities. The Deactivation and Decommissioning Focus Area (DDFA) of the DOE's Office of Science and Technology (OST) sponsors large-scale demonstration and deployment projects (LSDDPs). At these LSDDPs, developers and vendors of improved or innovative technologies showcase products that are potentially beneficial to the DOE's projects and to others in the D&D community. Benefits sought include decreased health and safety risks to personnel and the environment, increased productivity, and decreased costs of operation. The Idaho National Engineering and Environmental Laboratory (INEEL) generated a list of statements defining specific needs and problems where improved technology could be incorporated into ongoing D&D tasks. One such need is to reduce the volume of waste copper wire and cable generated by D&D. Deactivation and decommissioning activities of nuclear facilities generates hundreds of tons of contaminated copper cable, which are sent to radioactive waste disposal sites. The Copper Cable Recycling Technology separates the clean copper from contaminated insulation and dust materials in these cables. The recovered copper can then be reclaimed and, more importantly, landfill disposal volumes can be reduced. The existing baseline technology for disposing radioactively contaminated cables is to package the cables in wooden storage boxes and dispose of the cables in radioactive waste disposal sites. The Copper Cable Recycling Technology is applicable to facility decommissioning projects at many Department of Energy (DOE) nuclear facilities and commercial nuclear power plants undergoing decommissioning activities. The INEEL Copper Cable Recycling Technology Demonstration investigated the effectiveness and efficiency to recycle 13.5 tons of copper cable. To determine the effectiveness of separating out radioactive contamination, the copper cable was coated with a surrogate contaminant. The demonstration took place at the Bonneville County Technology Center in Idaho Falls, Idaho.

  7. Study of an ammonia-based wet scrubbing process in a continuous flow system

    SciTech Connect

    Mao, James X.; Lee, Anita S.; Kitchin, John R.; Nulwala, Hunaid B.; Luebke, David R.; Damodaran, Krishnan

    2013-01-01

    A continuous gas and liquid flow, regenerative scrubbing process for CO{sub 2} capture was demonstrated at the bench-scale level. An aqueous ammonia-based solution captures CO{sub 2} from simulated flue gas in an absorber and releases a nearly pure stream of CO{sub 2} in the regenerator. After the regeneration, the solution of ammonium compounds is recycled to the absorber. The design of a continuous flow unit was based on earlier exploratory results from a semi-batch reactor, where a CO{sub 2} and N{sub 2} simulated flue gas mixture flowed through a well-mixed batch of ammonia-based solution. During the semi-batch tests, the solution was cycled between absorption and regeneration steps to measure the carrying capacity of the solution at various initial ammonia concentrations and temperatures. Consequentially, a series of tests were conducted on the continuous unit to observe the effect of various parameters on CO{sub 2} removal efficiency and regenerator effectiveness within the flow system. The parameters that were studied included absorber temperature, regenerator temperature, initial NH{sub 3} concentration, simulated flue gas flow rate, liquid solvent inventory in the flow system, and height of the packed-bed absorber. From this testing and subsequent testing, ammonia losses from both the absorption and regeneration steps were quantified, and attempts were made to maintain steady state during operations. Implications of experimental results with respect to process design are discussed.

  8. Modeling percolation in high-aspect-ratio fiber systems. II. The effect of waviness on the percolation onset

    NASA Astrophysics Data System (ADS)

    Berhan, L.; Sastry, A. M.

    2007-04-01

    The onset of electrical percolation in nanotube-reinforced composites is often modeled by considering the geometric percolation of a system of penetrable, straight, rigid, capped cylinders, or spherocylinders, despite the fact that embedded nanotubes are not straight and do not penetrate one another. In Part I of this work we investigated the applicability of the soft-core model to the present problem, and concluded that the hard-core approach is more appropriate for modeling electrical percolation onset in nanotube-reinforced composites and other high-aspect-ratio fiber systems. In Part II, we investigate the effect of fiber waviness on percolation onset. Previously, we studied extensively the effect of joint morphology and waviness in two-dimensional nanotube networks. In this work, we present the results of Monte Carlo simulations studying the effect of waviness on the percolation threshold of randomly oriented fibers in three dimensions. The excluded volumes of fibers were found numerically, and relationships between these and percolation thresholds for two different fiber morphologies were found. We build on the work of Part I, and extend the results of our soft-core, wavy fiber simulations to develop an analytical solution using the more relevant hard-core model. Our results show that for high- aspect-ratio fibers, the generally accepted inverse proportionality between percolation threshold and excluded volume holds, independent of fiber waviness. This suggests that, given an expression for excluded volume, an analytical solution can be derived to identify the percolation threshold of a system of high-aspect-ratio fibers, including nanotube-reinforced composites. Further, we show that for high aspect ratios, the percolation threshold of the wavy fiber networks is directly proportional to the analytical straight fiber solution and that the constant of proportionality is a function of the nanotube waviness only. Thus the onset of percolation can be adequately modeled by applying a factor based on fiber geometry to the analytical straight fiber solution.

  9. Decontaminating Aluminum/Ammonia Heat Pipes

    NASA Technical Reports Server (NTRS)

    Jones, J. A.

    1985-01-01

    Internal gas slugs reduced or eliminated. Manufacturing method increases efficiency of aluminum heat pipes in which ammonia is working fluid by insuring pipe filled with nearly pure charge of ammonia. In new process heat pipe initially closed with stainless-steel valve instead of weld so pipe put through several cycles of filling, purging, and accelerated aging.

  10. Regeneration of ammonia borane from polyborazylene

    DOEpatents

    Sutton, Andrew; Gordon, John C; Ott, Kevin C; Burrell, Anthony K

    2013-02-05

    Method of producing ammonia borane, comprising providing a reagent comprising a dehydrogenated material in a suitable solvent; and combining the reagent with a reducing agent comprising hydrazine, a hydrazine derivative, or combinations thereof, in a reaction which produces a mixture comprising ammonia borane.

  11. CHRONIC TOXICITY OF AMMONIA OF RAINBOW TROUT

    EPA Science Inventory

    The chronic effects of ammonia to rainbow trout Salmo gairdneri were studied in a laboratory test conducted over a 5-year period. Fish were tested at five concentrations over the range 0.01-0.07 mg/liter un-ionized ammonia; the mean pH of the test water was 7.7, and the mean temp...

  12. Ammonia Solubility in High Concentration Salt Solutions

    SciTech Connect

    HEDENGREN, D.C.

    2000-02-01

    Solubility data for ammonia in water and various dilute solutions are abundant in the literature. However, there is a noticeable lack of ammonia solubility data for high salt, basic solutions of various mixtures of salts including those found in many of the Hanford Washington underground waste tanks. As a result, models based on solubility data for dilute salt solutions have been used to extrapolate to high salt solutions. These significant extrapolations need to be checked against actual laboratory data. Some indirect vapor measurements have been made. A more direct approach is to determine the ratio of solubility of ammonia in water to its solubility in high salt solutions. In various experiments, pairs of solutions, one of which is water and the other a high salt solution, are allowed to come to equilibrium with a common ammonia vapor pressure. The ratio of concentrations of ammonia in the two solutions is equal to the ratio of the respective ammonia solubilities (Henry's Law constants) at a given temperature. This information can then be used to refine the models that predict vapor space compositions of ammonia. Ammonia at Hanford is of concern because of its toxicity in the environment and its contribution to the flammability of vapor space gas mixtures in waste tanks.

  13. Jupiter's ammonia clouds—localized or ubiquitous?

    Microsoft Academic Search

    S. K. Atreya; A. S. Wong; K. H. Baines; M. H. Wong; T. C. Owen

    2005-01-01

    From an analysis of the Galileo Near Infrared Imaging Spectrometer (NIMS) data, Baines et al. (Icarus 159 (2002) 74) have reported that spectrally identifiable ammonia clouds (SIACs) cover less than 1% of Jupiter. Localized ammonia clouds have been identified also in the Cassini Composite Infrared Spectrometer (CIRS) observations (Planet. Space Sci. 52 (2004a) 385). Yet, ground-based, satellite and spacecraft observations

  14. Evaluation of ammonia emissions from broiler litter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia emissions from poultry litter results in air pollution and can cause high levels of ammonia in poultry houses, which negatively impacts bird performance. The objectives of this study were to: (1) conduct a nitrogen (N) mass balance in broiler houses by measuring the N inputs (bedding, chick...

  15. Method for releasing hydrogen from ammonia borane

    DOEpatents

    Varma, Arvind; Diwan, Moiz; Shafirovich, Evgeny; Hwang, Hyun-Tae; Al-Kukhun, Ahmad

    2013-02-19

    A method of releasing hydrogen from ammonia borane is disclosed. The method comprises heating an aqueous ammonia borane solution to between about 80-135.degree. C. at between about 14.7 and 200 pounds per square inch absolute (psia) to release hydrogen by hydrothermolysis.

  16. EFFLUENT AMMONIA VARIABILITY FROM NITRIFICATION FACILITIES

    EPA Science Inventory

    A statistical analysis was made on several years worth of daily effluent ammonia concentrations from seven Ohio nitrification plants. Significant seasonal and annual trends were found in six of the plants. The full range of ammonia variability within a season could not generally ...

  17. Inactivation of Cryptosporidium parvum Oocysts by Ammonia

    Microsoft Academic Search

    MICHAEL B. JENKINS; DWIGHT D. BOWMAN; WILLIAM C. GHIORSE

    1998-01-01

    The survival of Cryptosporidium parvum oocysts in soil and water microhabitats may be affected by the en- vironmental production and release of free ammonia. The objective of this study was to determine the effects of increasing free ammonia concentrations and times of exposure on oocyst viability. Wild-type oocysts were obtained from naturally infected calf feces by chemical (continuous-flow) centrifugation and

  18. METHODOLOGY AND INSTRUMENTATION TO MEASURE GASEOUS AMMONIA

    EPA Science Inventory

    Methodology for the time integrated collection and analysis of atmospheric ammonia was developed. Ammonia is primarily measured because it can react with SOx to produce ammonium sulfate. Since SOx is one of the principle air pollutants, it is important to determine its atmospheri...

  19. Why recycle? A comparison of recycling motivations in four communities

    NASA Astrophysics Data System (ADS)

    Vining, Joanne; Linn, Nancy; Burdge, Rabel J.

    1992-11-01

    Four Illinois communities with different sociode-mographic compositions and at various stages of planning for solid waste management were surveyed to determine the influence of sociodemographic variables and planning stages on the factors that motivate recycling behavior. A factor analysis of importance ratings of reasons for recycling and for not recycling yielded five factors interpreted as altruism, personal inconvenience, social influences, economic incentives, and household storage. The four communities were shown to be significantly different in multivariate analyses of the five motivational factors. However, attempts to explain these community differences with regression analyses, which predicted the motivational factors with dummy codes for planning stages, a measure of self-reported recycling behavior, and sociodemographic measures were unsatisfactory. Contrary to expectation, the solid waste management planning stages of the cities (curbside pickup, recycling dropoff center, and planning in progress) contributed only very slightly to the prediction of motivational factors for recycling. Community differences were better explained by different underlying motivational structures among the four communities. Altruistic reasons for recycling (e.g., conserving resources) composed the only factor which was similar across the four communities. This factor was also perceived to be the most important reason for recycling by respondents from all four communities. The results of the study supported the notion that convenient, voluntary recycling programs that rely on environmental concern and conscience for motivation are useful approaches to reducing waste.

  20. A simple proof of exponential decay in the two dimensional percolation model

    E-print Network

    Zhang, Yu

    2008-01-01

    Kesten showed the exponential decay of percolation probability in the subcritical phase for the two-dimensional percolation model. This result implies his celebrated computation that $p_c=0.5$ for bond percolation in the square lattice, and site percolation in the triangular lattice, respectively. In this paper, we present a simpler proof for Kesten's theorem.

  1. Multiple percolation tunneling staircase in metal-semiconductor nanoparticle composites

    SciTech Connect

    Mukherjee, Rupam; Huang, Zhi-Feng; Nadgorny, Boris [Department of Physics and Astronomy, Wayne State University, Detroit, Michigan 48201 (United States)

    2014-10-27

    Multiple percolation transitions are observed in a binary system of RuO{sub 2}-CaCu{sub 3}Ti{sub 4}O{sub 12} metal-semiconductor nanoparticle composites near percolation thresholds. Apart from a classical percolation transition, associated with the appearance of a continuous conductance path through RuO{sub 2} metal oxide nanoparticles, at least two additional tunneling percolation transitions are detected in this composite system. Such behavior is consistent with the recently emerged picture of a quantum conductivity staircase, which predicts several percolation tunneling thresholds in a system with a hierarchy of local tunneling conductance, due to various degrees of proximity of adjacent conducting particles distributed in an insulating matrix. Here, we investigate a different type of percolation tunneling staircase, associated with a more complex conductive and insulating particle microstructure of two types of non-spherical constituents. As tunneling is strongly temperature dependent, we use variable temperature measurements to emphasize the hierarchical nature of consecutive tunneling transitions. The critical exponents corresponding to specific tunneling percolation thresholds are found to be nonuniversal and temperature dependent.

  2. Percolation exponents and thresholds obtained from the nearly ideal continuum percolation system graphite-boron nitride

    Microsoft Academic Search

    Junjie Wu; D. S. McLachlan

    1997-01-01

    Compressed disks made from graphite and, its mechanical but not electrical isomorph, boron nitride as well as graphite-boron nitride powders, undergoing compression, are nearly ideal continuum percolation systems, as the ratio of their conductivities is nearly 10-18 and the scatter of the experimental points near the critical volume fraction phic is very small. The following measurements, with the characteristic exponent(s)

  3. Autotrophic ammonia oxidation by soil thaumarchaea

    PubMed Central

    Zhang, Li-Mei; Offre, Pierre R.; He, Ji-Zheng; Verhamme, Daniel T.; Nicol, Graeme W.; Prosser, James I.

    2010-01-01

    Nitrification plays a central role in the global nitrogen cycle and is responsible for significant losses of nitrogen fertilizer, atmospheric pollution by the greenhouse gas nitrous oxide, and nitrate pollution of groundwaters. Ammonia oxidation, the first step in nitrification, was thought to be performed by autotrophic bacteria until the recent discovery of archaeal ammonia oxidizers. Autotrophic archaeal ammonia oxidizers have been cultivated from marine and thermal spring environments, but the relative importance of bacteria and archaea in soil nitrification is unclear and it is believed that soil archaeal ammonia oxidizers may use organic carbon, rather than growing autotrophically. In this soil microcosm study, stable isotope probing was used to demonstrate incorporation of 13C-enriched carbon dioxide into the genomes of thaumarchaea possessing two functional genes: amoA, encoding a subunit of ammonia monooxygenase that catalyses the first step in ammonia oxidation; and hcd, a key gene in the autotrophic 3-hydroxypropionate/4-hydroxybutyrate cycle, which has been found so far only in archaea. Nitrification was accompanied by increases in archaeal amoA gene abundance and changes in amoA gene diversity, but no change was observed in bacterial amoA genes. Archaeal, but not bacterial, amoA genes were also detected in 13C-labeled DNA, demonstrating inorganic CO2 fixation by archaeal, but not bacterial, ammonia oxidizers. Autotrophic archaeal ammonia oxidation was further supported by coordinate increases in amoA and hcd gene abundance in 13C-labeled DNA. The results therefore provide direct evidence for a role for archaea in soil ammonia oxidation and demonstrate autotrophic growth of ammonia oxidizing archaea in soil. PMID:20855593

  4. Recycling Bin Guide Locations and prices

    E-print Network

    Kirschner, Denise

    Recycling Bin Guide Locations and prices Metal Bins Deskside Bins with Side Saddle Rubbermaid Bins.58 for auxiliaries. And Non-Public Areas Public Offices Non-Public Recyclables Recyclables RecyclablesTrash Trash Trash #12;New Recycling Bin Guidelines Frequently Asked Questions (as of December 2008) · Why

  5. Recycling Best Practices Report August 2011

    E-print Network

    Kirschner, Denise

    Recycling Best Practices Report August 2011 Elizabeth Fox, Recycling Best Practices Intern Office of Waste Reduction and Recycling University of Michigan Plant Building and Grounds Services #12;Recycling Best Practices Report Office of Waste Reduction and Recycling 1 Executive Summary Due to the high

  6. Percolation transport and filament formation in nanocrystalline silicon nanowires

    NASA Astrophysics Data System (ADS)

    Fischer, S.; Osorio, C.; Williams, N. E.; Ayas, S.; Silva, H.; Gokirmak, A.

    2013-04-01

    Under sufficient electrical bias, electron percolation in nanocrystalline silicon can lead to rapid self-heating and formation of highly conductive, molten filaments, and local crystallization upon cooling. Self-heated nanocrystalline silicon nanowires are modeled using 2-D finite element simulations using temperature dependent material parameters. Nanocrystalline silicon is modeled as randomly distributed isolated crystalline grains embedded in an amorphous matrix. Highly conductive, nanometer-width molten filaments form from percolation paths at the beginning of nanosecond voltage pulses. In a short period of time, the most conductive filament starts drawing all the current (with current densities > 100 MA/cm2) while the remaining percolation paths resolidify.

  7. Percolation on the Signal to Interference Ratio Graph with Fading

    E-print Network

    Vaze, Rahul

    2011-01-01

    A wireless communication network is considered where any two nodes are connected if the signal-to-interference ratio (SIR) between them is greater than a threshold. We consider the the path-loss plus fading model of wireless signal propagation. Assuming that the nodes of the wireless network are distributed as a Poisson point process (PPP), percolation (formation of an unbounded connected cluster) on the resulting SIR graph is studied as a function of the density of the PPP. We study the super critical regime of percolation and show that for a small enough threshold, there exists a closed interval of densities for which percolation happens with non-zero probability.

  8. Percolation and permeability of heterogeneous fracture networks

    NASA Astrophysics Data System (ADS)

    Adler, Pierre; Mourzenko, Valeri; Thovert, Jean-François

    2013-04-01

    Natural fracture fields are almost necessarily heterogeneous with a fracture density varying with space. Two classes of variations are quite frequent. In the first one, the fracture density is decreasing from a given surface; the fracture density is usually (but not always see [1]) an exponential function of depth as it has been shown by many measurements. Another important example of such an exponential decrease consists of the Excavated Damaged Zone (EDZ) which is created by the excavation process of a gallery [2,3]. In the second one, the fracture density undergoes some local random variations around an average value. This presentation is mostly focused on the first class and numerical samples are generated with an exponentially decreasing density from a given plane surface. Their percolation status and hydraulic transmissivity can be calculated by the numerical codes which are detailed in [4]. Percolation is determined by a pseudo diffusion algorithm. Flow determination necessitates the meshing of the fracture networks and the discretisation of the Darcy equation by a finite volume technique; the resulting linear system is solved by a conjugate gradient algorithm. Only the flow properties of the EDZ along the directions which are parallel to the wall are of interest when a pressure gradient parallel to the wall is applied. The transmissivity T which relates the total flow rate per unit width Q along the wall through the whole fractured medium to the pressure gradient grad p, is defined by Q = - T grad p/mu where mu is the fluid viscosity. The percolation status and hydraulic transmissivity are systematically determined for a wide range of decay lengths and anisotropy parameters. They can be modeled by comparison with anisotropic fracture networks with a constant density. A heuristic power-law model is proposed which accurately describes the results for the percolation threshold over the whole investigated range of heterogeneity and anisotropy. Then, the data for transmissivity are presented. A simple parallel flow model is introduced. The flow properties of the medium vary with the distance z from the wall. However, the macroscopic pressure gradient does not depend on z, and the flow lines are in average parallel to the wall. Hence, the overall transmissivity is tentatively estimated by a parallel flow model, where a layer at depth z behaves as a fractured medium with uniform properties corresponding to the state at this position in the medium. It yields an explicit analytical expression for the transmissivity as a function of the heterogeneity and anisotropy parameters, and it successfully accounts for all the numerical data. Graphical tools are provided from which first estimates can be quickly and easily obtained. A short overview of the second class of heterogeneous media will be given. [1] Barton C.A., Zoback M.D., J. Geophys. Res., 97B, 5181-5200 (1992). [2] Bossart P. et al, Eng. Geol., vol. 66, 19-38 (2002). [3] Thovert J.-F. et al, Eng. Geol., 117, 39-51 (2011). [4] Adler P.M. et al, Fractured porous media, Oxford U. Press, 2012.

  9. Isoperimetry in two-dimensional percolation

    E-print Network

    Marek Biskup; Oren Louidor; Eviatar B. Procaccia; Ron Rosenthal

    2015-01-14

    We consider the unique infinite connected component of supercritical bond percolation on the square lattice and study the geometric properties of isoperimetric sets, i.e., sets with minimal boundary for a given volume. For almost every realization of the infinite connected component we prove that, as the volume of the isoperimetric set tends to infinity, its asymptotic shape can be characterized by an isoperimetric problem in the plane with respect to a particular norm. As an application we then show that the anchored isoperimetric profile with respect to a given point as well as the Cheeger constant of the giant component in finite boxes scale to deterministic quantities. This settles a conjecture of Itai Benjamini for the plane.

  10. Percolation of localized attack on complex networks

    NASA Astrophysics Data System (ADS)

    Shao, Shuai; Huang, Xuqing; Stanley, H. Eugene; Havlin, Shlomo

    2015-02-01

    The robustness of complex networks against node failure and malicious attack has been of interest for decades, while most of the research has focused on random attack or hub-targeted attack. In many real-world scenarios, however, attacks are neither random nor hub-targeted, but localized, where a group of neighboring nodes in a network are attacked and fail. In this paper we develop a percolation framework to analytically and numerically study the robustness of complex networks against such localized attack. In particular, we investigate this robustness in Erd?s–Rényi networks, random-regular networks, and scale-free networks. Our results provide insight into how to better protect networks, enhance cybersecurity, and facilitate the design of more robust infrastructures.

  11. Regeneration of ammonia borane spent fuel

    SciTech Connect

    Sutton, Andrew David [Los Alamos National Laboratory; Davis, Benjamin L [Los Alamos National Laboratory; Gordon, John C [Los Alamos National Laboratory

    2009-01-01

    A necessary target in realizing a hydrogen (H{sub 2}) economy, especially for the transportation sector, is its storage for controlled delivery, presumably to an energy producing fuel cell. In this vein, the U.S. Department of Energy's Centers of Excellence (CoE) in Hydrogen Storage have pursued different methodologies, including metal hydrides, chemical hydrides, and sorbents, for the expressed purpose of supplanting gasoline's current > 300 mile driving range. Chemical H{sub 2} storage has been dominated by one appealing material, ammonia borane (H{sub 3}N-BH{sub 3}, AB), due to its high gravimetric capacity of H{sub 2} (19.6 wt %) and low molecular weight (30.7 g mol{sup -1}). In addition, AB has both hydridic and protic moieties, yielding a material from which H{sub 2} can be readily released in contrast to the loss of H{sub 2} from C{sub 2}H{sub 6} which is substantially endothermic. As such, a number of publications have described H{sub 2} release from amine boranes, yielding various rates depending on the method applied. The viability of any chemical H{sub 2} storage system is critically dependent on efficient recyclability, but reports on the latter subject are sparse, invoke the use of high energy reducing agents, and suffer from low yields. Our group is currently engaged in trying to find and fully demonstrate an energy efficient regeneration process for the spent fuel from H{sub 2} depleted AB with a minimum number of steps. Although spent fuel composition depends on the dehydrogenation method, we have focused our efforts on the spent fuel resulting from metal-based catalysis, which has thus far shown the most promise. Metal-based catalysts have produced the fastest rates for a single equivalent of H{sub 2} released from AB and up to 2.5 equiv. of H{sub 2} can be produced within 2 hours. While ongoing work is being carried out to tailor the composition of spent AB fuel, a method has been developed for regenerating the predominant product, polyborazylene (PB) which can be obtained readily from the decomposition of borazine or from nickel carbene catalyst dehydrogenation. In this cycle, the PB is digested with benzenedithiol to yield two products which can both be converted to AB using Bu{sub 3}SnH and BU{sub 2}SnH{sub 2} as reductants. However, in a real world situation the process becomes more complicated for several reasons. Bu{sub 2}SnH{sub 2} is thermally unstable and therefore not viable in a process scale operation. This has led to the development of Bu{sub 3}SnH as the sole reductant although this requires an additional amine exchange step in order to facilitate the reduction to an amine-borane which can then be converted to AB. The tin by-products also need to be recycled in order to maximize the overall energy efficiency and therefore minimize the overall cost of the process. In addition, on an industrial scale, the mass of the tin reductant generates significant cost due to the manipulation of the relatively large quantities involved so reducing the mass at this stage would be of vast significance. We will discuss further developments made to the tin recycle component of the cycle (including methods to minimize tin usage) and investigate new methods of reduction of the digested products, primarily focusing on lighter reductants, including lighter analogs of Bu{sub 2}SnH{sub 2} and Bu{sub 3}SnH. These advances will have a significant impact on the cost of production and therefore the viability of AB as a fuel. Minimization of tin reagents and their recycle will contribute to reduction of the overall cost of AB regeneration and all stages of AB regeneration have been demonstrated.

  12. Emulsified industrial oils recycling

    SciTech Connect

    Gabris, T.

    1982-04-01

    The industrial lubricant market has been analyzed with emphasis on current and/or developing recycling and re-refining technologies. This task has been performed for the United States and other industrialized countries, specifically France, West Germany, Italy and Japan. Attention has been focused at emulsion-type fluids regardless of the industrial application involved. It was found that emulsion-type fluids in the United States represent a much higher percentage of the total fluids used than in other industrialized countries. While recycling is an active matter explored by the industry, re-refining is rather a result of other issues than the mere fact that oil can be regenerated from a used industrial emulsion. To extend the longevity of an emulsion is a logical step to keep expenses down by using the emulsion as long as possible. There is, however, another important factor influencing this issue: regulations governing the disposal of such fluids. The ecological question, the respect for nature and the natural balances, is often seen now as everybody's task. Regulations forbid dumping used emulsions in the environment without prior treatment of the water phase and separation of the oil phase. This is a costly procedure, so recycling is attractive since it postpones the problem. It is questionable whether re-refining of these emulsions - as a business - could stand on its own if these emulsions did not have to be taken apart for disposal purposes. Once the emulsion is separated into a water and an oil phase, however, re-refining of the oil does become economical.

  13. Recycler barrier RF buckets

    SciTech Connect

    Bhat, C.M.; /Fermilab

    2011-03-01

    The Recycler Ring at Fermilab uses a barrier rf systems for all of its rf manipulations. In this paper, I will give an overview of historical perspective on barrier rf system, the longitudinal beam dynamics issues, aspects of rf linearization to produce long flat bunches and methods used for emittance measurements of the beam in the RR barrier rf buckets. Current rf manipulation schemes used for antiproton beam stacking and longitudinal momentum mining of the RR beam for the Tevatron collider operation are explained along with their importance in spectacular success of the Tevatron luminosity performance.

  14. Recycled rubber roads

    SciTech Connect

    Not Available

    1989-02-01

    The paper describes several innovative approaches for recycling old tires in the construction of roads. In one, 18 inches of shredded tire chips (2 X 2 inches) were used on top of 6-8 inches of small stone to construct a road across a sanitary landfill. No compacting or linders were needed. In another application, sidewall mats linked together with steel strapping were used as a sub-base for a road across a swampy area. A third application uses 1/2 inch bits of groundup rubber tires as a replacement for aggregate in an asphalt road base.

  15. Energy and Recycling

    NSDL National Science Digital Library

    Energy and Garbage is one section of a US Department of Energy's educational Web site for kids. Features of this Web site include a section detailing the connection between energy and garbage, a thorough introduction to the history of garbage that includes facts and figures on how much waste we produce, information on recycling and reducing garbage at the source, and much more. The information in this Web site is presented in a friendly, narrative style. A short downloadable activity titled Energy from Garbage, created by the National Energy Education Development Project, is also available (grades 4-6).

  16. From Earth to Space: Application of Biological Treatment for the Removal of Ammonia from Water

    NASA Technical Reports Server (NTRS)

    Pickering, Karen; Adam, Niklas; White, Dawn; Ghosh, Amlan; Seidel, Chad

    2014-01-01

    Managing ammonia is often a challenge in both drinking water and wastewater treatment facilities. Ammonia is unregulated in drinking water, but its presence may result in numerous water quality issues in the distribution system such as loss of residual disinfectant, nitrification, and corrosion. Ammonia concentrations need to be managed in wastewater effluent to sustain the health of receiving water bodies. Biological treatment involves the microbiological oxidation of ammonia to nitrate through a two-step process. While nitrification is common in the environment, and nitrifying bacteria can grow rapidly on filtration media, appropriate conditions, such as the presence of dissolved oxygen and required nutrients, need to be established. This presentation will highlight results from two ongoing research programs - one at NASA's Johnson Space Center, and the other at a drinking water facility in California. Both programs are designed to demonstrate nitrification through biological treatment. The objective of NASA's research is to be able to recycle wastewater to potable water for spaceflight missions. To this end, a biological water processor (BWP) has been integrated with a forward osmosis secondary treatment system (FOST). Bacteria mineralize organic carbon to carbon dioxide as well as ammonia-nitrogen present in the wastewater to nitrogen gas, through a combination of nitrification and denitrification. The effluent from the BWP system is low in organic contaminants, but high in total dissolved solids. The FOST system, integrated downstream of the BWP, removes dissolved solids through a combination of concentration-driven forward osmosis and pressure driven reverse osmosis. The integrated system testing planned for this year is expected to produce water that requires only a polishing step to meet potable water requirements for spaceflight. The pilot study in California is being conducted on Golden State Water Company's Yukon wells that have hydrogen sulfide odor, color, total organic carbon, bromide, iron and manganese in addition to ammonia. A treatment evaluation, conducted in 2011, recommended the testing of biological oxidation filtration for the removal of ammonia and production of biologically stable water. An 8-month pilot testing program was conducted to develop and optimize key design and operational variables. Steadystate operational data was collected to demonstrate long-term performance and inform California Department of Public Health permitting of the full-scale process. As ammonia continues to present challenges to water and wastewater systems, innovative strategies such as biological treatment can be applied to successfully manage it. This presentation will discuss application of cutting-age research being conducted by NASA that will bridge existing information gaps, and benefit municipal utilities.

  17. From Earth to Space: Application of Biological Treatment for the Removal of Ammonia from Water

    NASA Technical Reports Server (NTRS)

    Ghosh, Amlan; Seidel, Chad; Adam, Niklas; Pickering, Karen; White, Dawn

    2014-01-01

    Managing ammonia is often a challenge in both drinking water and wastewater treatment facilities. Ammonia is unregulated in drinking water, but its presence may result in numerous water quality issues in the distribution system such as loss of residual disinfectant, nitrification, and corrosion. Ammonia concentrations need to be managed in wastewater effluent to sustain the health of receiving water bodies. Biological treatment involves the microbiological oxidation of ammonia to nitrate through a two-step process. While nitrification is common in the environment, and nitrifying bacteria can grow rapidly on filtration media, appropriate conditions, such as the presence of dissolved oxygen and required nutrients, need to be established. This presentation will highlight results from two ongoing research programs - one at NASA's Johnson Space Center, and the other at a drinking water facility in California. Both programs are designed to demonstrate nitrification through biological treatment. The objective of NASA's research is to be able to recycle wastewater to potable water for spaceflight mission. To this end, a biological water processor (BWP) has been integrated with a forward osmosis secondary treatment system (FOST). Bacteria mineralize organic carbon to carbon dioxide as well as ammonia-nitrogen present in the wastewater to nitrogen gas, through a combination of nitrification and denitrification. The effluent from the BWP system is low in organic contaminants, but high in total dissolved solids. The FOST system, integrated downstream of the BWP, removes dissolved solids through a combination of concentration-driven forward osmosis and pressure driven reverse osmosis. The integrated system testing planned for this year is expected to produce water that requires only a polishing step to meet potable water requirements for spaceflight. The pilot study in California is being conducted on Golden State Water Company's Yukon wellsthat have hydrogen sulfide odor, color, total organic carbon, bromide, iron and manganese in addition to ammonia. A treatment evaluation, conducted in 2011, recommended the testing of biological oxidation filtration for the removal of ammonia and production of biologically stable water. A 8-month pilot testing program was conducted to develop and optimize key design and operational variables. Steadystate operational data was collected to demonstrate long-term performance and inform California Department of Public Health permitting of the full-scale process. As ammonia continues to present challenges to water and wastewater systems, innovative strategies such as biological treatment can be applied to successfully manage it. This presentation will discuss application of cutting-age research being conducted by NASA that will bridge existing information gaps, and benefit municipal utilities.

  18. Closed Loop Recycling of PreservativeClosed Loop Recycling of Preservative Treated WoodTreated Wood

    E-print Network

    Closed Loop Recycling of PreservativeClosed Loop Recycling of Preservative Treated WoodTreated WoodDisposal problem Recycling potentialRecycling potential ValueValue--added productsadded products Closed loop recyclingClosed loop recycling #12;Major Current Disposal OptionsMajor Current Disposal Options Incineration

  19. Prediction of Mass Absorption of Ammonia Vapor into Ammonia Water Solution

    NASA Astrophysics Data System (ADS)

    Monde, Masanori; Mustafa, Hatem

    Mass absorption rate of ammonia vapor into ammonia water solution is investigated experimentally, by feeding a superheated ammonia vapor into a test cell to be absorbed into stagnant pool of ammonia water solution with an initial mass concentration of Ci = 0.0 to 0.63 kg/kg. The flowing of the ammonia vapor is due to a pressure difference of ?P = 50 to 300 kPa between the ammonia vapor cylinder and the pressure of the test cell. The main objectives are, to investigate the effect of initial pressure difference on the absorption rate of ammonia vapor and to develop an equation which predicts the total absorbed mass of ammonia with initial pressure difference, initial concentration and time. The experiment shows that the total absorbed mass of ammonia linearly increases with increasing initial pressure difference. A correlation can be proposed to yield the total absorbed mass of ammonia measured in the experiment. In addition, the absorbed mass at no pressure difference, namely free absorption, could be estimated from the absorbed mass at initial pressure difference.

  20. Development of polymeric foams from recycled polyethylene and recycled gypsum

    Microsoft Academic Search

    A. Greco; A. Maffezzoli; O. Manni

    2005-01-01

    The extrusion foaming of recycled polyethylene through different foaming agents has been studied. Cellular structures were obtained in a single screw extruder with different grades of polyethylene (low and high density), using recycled gypsum and a commercial foaming agent (azodicarbonamide). Differential scanning calorimetry and thermogravimetric analysis were used to characterize the transition temperatures of the polyethylenes used, and the dissociation

  1. Vapor Phase Catalytic Ammonia Reduction

    NASA Technical Reports Server (NTRS)

    Flynn, Michael T.; Harper, Lynn D. (Technical Monitor)

    1994-01-01

    This paper discusses the development of a Vapor Phase Catalytic Ammonia Reduction (VPCAR) teststand and the results of an experimental program designed to evaluate the potential of the technology as a water purification process. In the experimental program the technology is evaluated based upon product water purity, water recovery rate, and power consumption. The experimental work demonstrates that the technology produces high purity product water and attains high water recovery rates at a relatively high specific power consumption. The experimental program was conducted in 3 phases. In phase I an Igepon(TM) soap and water mixture was used to evaluate the performance of an innovative Wiped-Film Rotating-Disk evaporator and associated demister. In phase II a phenol-water solution was used to evaluate the performance of the high temperature catalytic oxidation reactor. In phase III a urine analog was used to evaluate the performance of the combined distillation/oxidation functions of the processor.

  2. Ammonia synthesis using magnetic induction method (MIM)

    NASA Astrophysics Data System (ADS)

    Puspitasari, P.; Razak, J. Abd; Yahya, N.

    2012-09-01

    The most challenging issues for ammonia synthesis is to get the high yield. New approach of ammonia synthesis by using Magnetic Induction Method (MIM) and the Helmholtz Coils has been proposed. The ammonia detection was done by using Kjeldahl Method and FTIR. The system was designed by using Autocad software. The magnetic field of MIM was vary from 100mT-200mT and the magnetic field for the Helmholtz coils was 14mT. The FTIR result shows that ammonia has been successfully formed at stretching peaks 1097,1119,1162,1236, 1377, and 1464 cm-1. UV-VIS result shows the ammonia bond at 195nm of wavelength. The ammonia yield was increase to 244.72?mole/g.h by using the MIM and six pairs of Helmholtz coils. Therefore this new method will be a new promising method to achieve the high yield ammonia at ambient condition (at 25?C and 1atm), under the Magnetic Induction Method (MIM).

  3. Highly compressed ammonia forms an ionic crystal

    NASA Astrophysics Data System (ADS)

    Pickard, Chris J.; Needs, R. J.

    2008-10-01

    Ammonia is an important compound with many uses, such as in the manufacture of fertilizers, explosives and pharmaceuticals. As an archetypal hydrogen-bonded system, the properties of ammonia under pressure are of fundamental interest, and compressed ammonia has a significant role in planetary physics. We predict new high-pressure crystalline phases of ammonia (NH3) through a computational search based on first-principles density-functional-theory calculations. Ammonia is known to form hydrogen-bonded solids, but we predict that at higher pressures it will form ammonium amide ionic solids consisting of alternate layers of NH4+ and NH2- ions. These ionic phases are predicted to be stable over a wide range of pressures readily obtainable in laboratory experiments. The occurrence of ionic phases is rationalized in terms of the relative ease of forming ammonium and amide ions from ammonia molecules, and the volume reduction on doing so. We also predict that the ionic bonding cannot be sustained under extreme compression and that, at pressures beyond the reach of current static-loading experiments, ammonia will return to hydrogen-bonded structures consisting of neutral NH3 molecules.

  4. Low-cost anodes for ammonia electrooxidation

    NASA Astrophysics Data System (ADS)

    Selverston, Steven M.

    This research focused on the development of low-cost electrodes for the electrochemical oxidation of ammonia to nitrogen, a reaction that has possible applications in hydrogen generation, direct ammonia fuel cells, water treatment, and sensors. Statistical design of experiments was used to help develop an efficient and scalable process for electrodeposition of platinum with a specific electrochemical surface area of over 25 m2 /g. Catalyst surface area and activity were evaluated using cyclic voltammetry, and the material microstructure and morphology were investigated using x-ray diffraction and scanning electron microscopy. The synthesized electrodes were found to be active toward the ammonia electrooxidation reaction, particularly when supporting electrolyte was added. However, supporting electrolyte was not required in order to oxidize the ammonia. As proof of concept, a homemade direct ammonia fuel cell employing a commercial anion exchange membrane was tested at room temperature with gravity-fed fuel and without supporting electrolyte. At room temperature, with passive reactant supply and using dissolved oxygen at the cathode, the cell produced about one quarter the power of a direct methanol fuel cell that used active transport of humidified oxygen and preheated (50 °C) methanol. With continued development of the membrane, cathode and membrane electrode assembly, the passive direct ammonia fuel cell using anion exchange membrane could have performance similar to the equivalent direct methanol fuel cell, and it could benefit from many advantages of ammonia over methanol such as lower cost, higher energy density, and reduced greenhouse gas emissions.

  5. Seasonal variations of the effect of temperature on lethal and sublethal toxicities of ammonia for three common freshwater shredders.

    PubMed

    Dehedin, Arnaud; Piscart, Christophe; Marmonier, Pierre

    2013-01-01

    In a context of global change, increases in temperature and in ammonia concentration should strongly affect the crustaceans of wetlands. We experimentally examined, at three different seasons (i.e. winter, spring, and summer), the effect of temperature (12, 18, and 24°C) on the lethal (survival rates) and sublethal (oxygen consumption) toxicity of unionized ammonia (NH(3)) on the amphipods Gammarus pulex and Gammarus roeselii and the isopod Asellus aquaticus. Our results demonstrate (1) a gradient of increasing tolerance and survival from G. roeselii to G. pulex and A. aquaticus, (2) an increasing toxicity of ammonia with temperature, and (3) a strong seasonal variation of the tolerance to ammonia, with a higher tolerance of individuals in winter than in summer. However, the sub-lethal effect of ammonia on the oxygen consumption rate was species dependant and changed according to temperature or season. Global change and resulting variations in crustacean densities will potentially affect the ecosystem functioning (e.g. organic matter recycling). PMID:22910696

  6. 16 CFR 260.12 - Recyclable claims.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...the waste stream through an established recycling program for reuse or use in manufacturing...deception about the availability of recycling programs and collection sites to consumers. (1) When recycling facilities are available to a...

  7. 16 CFR 260.12 - Recyclable claims.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...the waste stream through an established recycling program for reuse or use in manufacturing...deception about the availability of recycling programs and collection sites to consumers. (1) When recycling facilities are available to a...

  8. Flooding and Recycling Authorizations Konstantin (Kosta) Beznosov

    E-print Network

    Flooding and Recycling Authorizations Konstantin (Kosta) Beznosov Laboratory for Education delivery channels with speculatively pre- computed authorizations and actively recycling them on a just Security Keywords authorization recycling, authorization flooding, access con- trol, authorization, publish

  9. The Economic Benefits of Recycling in Virginia

    E-print Network

    Lewis, Robert Michael

    The Economic Benefits of Recycling in Virginia Alexander P. Miller Hang T. Nguyen Samantha D, and the recycling contacts from the participating Solid Waste Planning Units discussed in this study. #12;3 Table Determinants of Recycling_______________________________ 12 State Reports

  10. Authorization Recycling in Hierarchical RBAC Systems

    E-print Network

    Authorization Recycling in Hierarchical RBAC Systems QIANG WEI University of British Columbia JASON these challenges. This paper introduces and evaluates the mechanisms for authorization "recycling" in RBAC evaluation results demonstrate that authorization recycling can improve the performance of distributed access

  11. Recycling Report FY2012 FY2012

    E-print Network

    Mohanty, Saraju P.

    FY 2013 Recycling Report FY2012 FY2012 Month Tons Revenue Tons Revenue Lbs Revenue Tons Revenue, Scrap) RESOURCES SAVED BY RECYCLING Total Tons Recycled 175.77 Cubic Feet of Landfill Space Conserved 15

  12. Network Robustness and Fragility: Percolation on Random Graphs

    NASA Astrophysics Data System (ADS)

    Callaway, Duncan S.; Newman, M. E. J.; Strogatz, Steven H.; Watts, Duncan J.

    2000-12-01

    Recent work on the Internet, social networks, and the power grid has addressed the resilience of these networks to either random or targeted deletion of network nodes or links. Such deletions include, for example, the failure of Internet routers or power transmission lines. Percolation models on random graphs provide a simple representation of this process but have typically been limited to graphs with Poisson degree distribution at their vertices. Such graphs are quite unlike real-world networks, which often possess power-law or other highly skewed degree distributions. In this paper we study percolation on graphs with completely general degree distribution, giving exact solutions for a variety of cases, including site percolation, bond percolation, and models in which occupation probabilities depend on vertex degree. We discuss the application of our theory to the understanding of network resilience.

  13. Network robustness and fragility: percolation on random graphs.

    PubMed

    Callaway, D S; Newman, M E; Strogatz, S H; Watts, D J

    2000-12-18

    Recent work on the Internet, social networks, and the power grid has addressed the resilience of these networks to either random or targeted deletion of network nodes or links. Such deletions include, for example, the failure of Internet routers or power transmission lines. Percolation models on random graphs provide a simple representation of this process but have typically been limited to graphs with Poisson degree distribution at their vertices. Such graphs are quite unlike real-world networks, which often possess power-law or other highly skewed degree distributions. In this paper we study percolation on graphs with completely general degree distribution, giving exact solutions for a variety of cases, including site percolation, bond percolation, and models in which occupation probabilities depend on vertex degree. We discuss the application of our theory to the understanding of network resilience. PMID:11136023

  14. The glue-ball spectrum of pure percolation

    E-print Network

    Stefano Lottini; Ferdinando Gliozzi

    2005-10-05

    We present a high-precision numerical study of 3D random percolation viewed as a confining gauge theory. Using large correlation matrices among multiform Wilson loops we determine the low-lying masses in various spin channels.

  15. Nickel-catalyzed monoarylation of ammonia.

    PubMed

    Borzenko, Andrey; Rotta-Loria, Nicolas L; MacQueen, Preston M; Lavoie, Christopher M; McDonald, Robert; Stradiotto, Mark

    2015-03-16

    Structurally diverse (hetero)aryl chloride, bromide, and tosylate electrophiles were employed in the Ni-catalyzed monoarylation of ammonia, including chemoselective transformations. The employed JosiPhos/[Ni(cod)2 ] catalyst system enables the use of commercially available stock solutions of ammonia, or the use of ammonia gas in these reactions, thereby demonstrating the versatility and potential scalability of the reported protocol. Proof-of-principle experiments established that air-stable [(JosiPhos)NiCl2 ] precatalysts can be employed successfully in such transformations. PMID:25573662

  16. Scaling of the spanning threshold in gradient percolation

    NASA Astrophysics Data System (ADS)

    Paterson, Lincoln

    2015-02-01

    A simple and fast way to apply correlations in percolation simulations is to apply a uniform gradient to the occupancy probabilities. For small networks, exact results are presented here for the spanning thresholds in site percolation with a gradient for networks up to 4 ×4 in two dimensions and 2 ×2 ×2 in three dimensions. Numerical results are provided for larger networks that extrapolate to a linear modification of the threshold proportional to the gradient for moderate values of the gradient.

  17. Anomalous Discontinuity at the Percolation Critical Point of Active Gels

    NASA Astrophysics Data System (ADS)

    Sheinman, M.; Sharma, A.; Alvarado, J.; Koenderink, G. H.; MacKintosh, F. C.

    2015-03-01

    We develop a percolation model motivated by recent experimental studies of gels with active network remodeling by molecular motors. This remodeling was found to lead to a critical state reminiscent of random percolation (RP), but with a cluster distribution inconsistent with RP. Our model not only can account for these experiments, but also exhibits an unusual type of mixed phase transition: We find that the transition is characterized by signatures of criticality, but with a discontinuity in the order parameter.

  18. Anomalous discontinuity at the percolation critical point of active gels.

    PubMed

    Sheinman, M; Sharma, A; Alvarado, J; Koenderink, G H; MacKintosh, F C

    2015-03-01

    We develop a percolation model motivated by recent experimental studies of gels with active network remodeling by molecular motors. This remodeling was found to lead to a critical state reminiscent of random percolation (RP), but with a cluster distribution inconsistent with RP. Our model not only can account for these experiments, but also exhibits an unusual type of mixed phase transition: We find that the transition is characterized by signatures of criticality, but with a discontinuity in the order parameter. PMID:25793855

  19. Social percolation and the influence of mass media

    NASA Astrophysics Data System (ADS)

    Proykova, Ana; Stauffer, Dietrich

    2002-09-01

    In the marketing model of Solomon and Weisbuch, people buy a product only if their neighbours tell them of its quality, and if this quality is higher than their own quality expectations. Now we introduce additional information from the mass media, which is analogous to the ghost field in percolation theory. The mass media shift the percolative phase transition observed in the model, and decrease the time after which the stationary state is reached.

  20. The ammonia hydrates—model mixed-hydrogen-bonded systems

    Microsoft Academic Search

    J. S. Loveday; R. J. Nelmes

    2004-01-01

    The three ammonia hydrates (ammonia dihydrate, ADH; ammonia monohydrate, AMH and ammonia hemihydrate, AHH) are amongst the simplest systems to contain mixed nitrogen oxygen–hydrogen bonds. In addition, ADH and AMH are believed to be common in the outer solar system, and their properties are important for modelling bodies such as Uranus, Neptune and Titan. Neutron diffraction studies have provided the

  1. AMMONIA EFFECTS ON MICROINVERTEBRATES AND FISH IN OUTDOOR EXPERIMENTAL STREAMS

    EPA Science Inventory

    Laboratory data on ammonia effects, the US EPA national water quality criteria for ammonia, and ammonia site-specific criteria were evaluated in four outdoor experimental streams (one control and three treatment streams) over a 76-week period. Calculated un-ionized ammonia concen...

  2. EVALUATION AND MANAGEMENT OF AMMONIA EMISSIONS FROM POULTRY LITTER

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia volatilization from poultry litter results in high levels of ammonia in poultry facilities, which negatively impacts bird performance and worker health. Ammonia emissions from the houses also cause atmospheric ammonia contamination. Although there is a tremendous concern about these emissio...

  3. Recycling Study Guide [Resource Packet].

    ERIC Educational Resources Information Center

    Wisconsin State Dept. of Natural Resources, Madison.

    This resource packet contains six documents developed by the Wisconsin Department of Natural Resources in order to help teachers infuse the environmental education topics of recycling and solid waste into social studies, art, English, health, mathematics, science, and environmental education classes. "Recycling Study Guide" contains 19 activities…

  4. Recycling technology of tire rubber

    Microsoft Academic Search

    Kenzo Fukumori; Mitsumasa Matsushita; Hirotaka Okamoto; Norio Sato; Yasuyuki Suzuki; Katsumasa Takeuchi

    2002-01-01

    Material recycling technology for automotive tire rubber waste was developed by the continuous devulcanization method. The deodorization during the recycling process has become possible by the newly developed method. The devulcanized rubber obtained by these methods from tire rubber waste, generated from both the manufacturing products and scrap tires, shows excellent mechanical properties applicable to the new tire rubber compounds

  5. Recycled Thermoplastic–Woodflour Composites

    Microsoft Academic Search

    D. Maldas; B. V. Kokta

    1994-01-01

    In the present study, composite materials were prepared from recycled PE, PP and commingled plastics, and waste cellulosics, e.g., sawdust (woodflour) of maple wood. In order to establish the compatibility, the woodflour was surface modified by precoating with maleated thermoplastics. Moreover, to improve the fire-retardancy, and at the same time to minimize the degradation of recycled plastics and woodflour various

  6. Climate Kids: Recycling Program Educator

    NSDL National Science Digital Library

    2013-11-26

    Using her countywide program as an example, a recycling educator offers incentives for recycling by providing data on energy savings and explaining how her county in Michigan supports the program. The Climate Kids website is a NASA education resource featuring articles, videos, images and games focused on the science of climate change.

  7. The Dynamic Earth: Recycling Naturally!

    ERIC Educational Resources Information Center

    Goldston, M. Jenice; Allison, Elizabeth; Fowler, Lisa; Glaze, Amanda

    2013-01-01

    This article begins with a thought-provoking question: What do you think of when you hear the term "recycle?" Many think about paper, glass, aluminum cans, landfills, and reducing waste by reusing some of these materials. How many of us ever consider the way the systems of Earth dynamically recycle its materials? In the following…

  8. Training Governments to Buy Recycled.

    ERIC Educational Resources Information Center

    Keller, Richard

    1995-01-01

    Describes a program developed by the Northeast Maryland Waste Disposal Authority to teach government buyers how to buy recycled materials. The program consists of a hands-on training seminar and a manual that offers step-by-step instructions for setting up a buy-recycled purchasing program. (LZ)

  9. Phase Diagram of Inhomogeneous Percolation with a Defect Plane

    NASA Astrophysics Data System (ADS)

    Iliev, G. K.; Janse van Rensburg, E. J.; Madras, N.

    2015-01-01

    Let be the -dimensional hypercubic lattice and let be an -dimensional sublattice, with . We consider a model of inhomogeneous bond percolation on at densities and , in which edges in are open with probability , and edges in open with probability . We generalize several classical results of (homogeneous) bond percolation to this inhomogeneous model. The phase diagram of the model is presented, and it is shown that there is a subcritical regime for and (where is the critical probability for homogeneous percolation in ), a bulk supercritical regime for , and a surface supercritical regime for and . We show that is a strictly decreasing function for , with a jump discontinuity at . We extend the Aizenman-Barsky differential inequalities for homogeneous percolation to the inhomogeneous model and use them to prove that the susceptibility is finite inside the subcritical phase. We prove that the cluster size distribution decays exponentially in the subcritical phase, and sub-exponentially in the supercritical phases. For a model of lattice animals with a defect plane, the free energy is related to functions of the inhomogeneous percolation model, and we show how the percolation transition implies a non-analyticity in the free energy of the animal model. Finally, we present simulation estimates of the critical curve.

  10. Aluminum: Recycling Comes of Age

    NASA Astrophysics Data System (ADS)

    Ballance, John B.

    1980-02-01

    Recycled aluminum is used by integrated producers who are capable of extracting aluminum from the ore, by non-integrated fabricators who rely on scrap for part of their production, and secondary smelters who depend entirely on scrap. Approximately 20% of the 14 billion pounds of aluminum shipped in the U.S. in 1978 came from recycled sources. Recycling aluminum requires only 5% of the energy needed to produce aluminum from the ore, and there are substantial savings in capital investment requirements. Since fabricators of aluminum products return nearly 100% of their scrap, future growth in recycled aluminum is possible largely through reclamation of post-consumer scrap. The basics of aluminum recycling are discussed, the technical and commercial problems outlined, and illustrations given of current industry activities.

  11. Sugar-Driven Prebiotic Synthesis of Ammonia from Nitrite

    NASA Astrophysics Data System (ADS)

    Weber, Arthur L.

    2010-03-01

    Reaction of 3-5 carbon sugars, glycolaldehyde, and ?-ketoaldehydes with nitrite under mild anaerobic aqueous conditions yielded ammonia, an essential substrate for the synthesis of nitrogen-containing molecules during abiogenesis. Under the same conditions, ammonia synthesis was not driven by formaldehyde, glyoxylate, 2-deoxyribose, and glucose, a result indicating that the reduction process requires an organic reductant containing either an accessible ?-hydroxycarbonyl group or an ?-dicarbonyl group. Small amounts of aqueous Fe+3 catalyzed the sugar-driven synthesis of ammonia. The glyceraldehyde concentration dependence of ammonia synthesis, and control studies of ammonia’s reaction with glyceraldehyde, indicated that ammonia formation is accompanied by incorporation of part of the synthesized ammonia into sugar-derived organic products. The ability of sugars to drive the synthesis of ammonia is considered important to abiogenesis because it provides a way to generate photochemically unstable ammonia at sites of sugar-based origin-of-life processes from nitrite, a plausible prebiotic nitrogen species.

  12. Defences against ammonia toxicity in tropical air-breathing fishes exposed to high concentrations of environmental ammonia: a review

    Microsoft Academic Search

    Y. K. Ip; S. F. Chew; J. M. Wilson; D. J. Randall

    2004-01-01

    In the tropics, air-breathing fishes can be exposed to environmental ammonia when stranded in puddles of water during the dry season, during a stay inside a burrow, or after agricultural fertilization. At low concentrations of environmental ammonia, NH 3 excretion is impeded, as in aerial exposure, leading to the accumulation of endogenous ammonia. At high concentrations of environmental ammonia, which

  13. INVESTIGATION OF THE ORION RESEARCH AMMONIA MONITOR

    EPA Science Inventory

    The Orion Research ammonia monitor was investigated using the Orion specifications and environmental considerations as a guide. Laboratory tests under controlled environmental conditions showed the electronic stability (drift) to be well within + or - 10 percent of reading over t...

  14. DEVELOPMENT AND SELECTION OF AMMONIA EMISSION FACTORS

    EPA Science Inventory

    This report compiles recent literature on ammonia (NH') emission factors for application in the United States. ost of the recent research supports acid deposition studies in the European community (specifically, the Netherlands, Great Britain, and Scandinavia) but some research h...

  15. Ultrafast dynamics of electrons in ammonia.

    PubMed

    Vöhringer, Peter

    2015-04-01

    Solvated electrons were first discovered in solutions of metals in liquid ammonia. The physical and chemical properties of these species have been studied extensively for many decades using an arsenal of electrochemical, spectroscopic, and theoretical techniques. Yet, in contrast to their hydrated counterpart, the ultrafast dynamics of ammoniated electrons remained completely unexplored until quite recently. Femtosecond pump-probe spectroscopy on metal-ammonia solutions and femtosecond multiphoton ionization spectroscopy on the neat ammonia solvent have provided new insights into the optical properties and the reactivities of this fascinating species. This article reviews the nature of the optical transition, which gives the metal-ammonia solutions their characteristic blue appearance, in terms of ultrafast relaxation processes involving bound and continuum excited states. The recombination processes following the injection of an electron via photoionization of the solvent are discussed in the context of the electronic structure of the liquid and the anionic defect associated with the solvated electron. PMID:25493716

  16. High-pressure studies of ammonia hydrates 

    E-print Network

    Wilson, Craig W.

    2014-06-28

    Ammonia and water are major components of many planetary bodies, from comets and icy moons such as Saturn's Titan to the interiors of the planets Neptune and Uranus. Under a range of high pressures and/or low temperatures known ...

  17. Exploring Waste and Recycling

    NSDL National Science Digital Library

    Camann, Eleanor

    This resource, created by Eleanor Camann of Red Rocks Community College, will introduce students to the concept of sustainability in terms of waste products and recycling practices. The overall premise of the project is to "get students to think critically about which earth materials are used to make things, and where all the waste from both mining and consumption ends up." The activity employs skills in basic mathematics, reasoning and writing. It also crosses disciplines by implementing skills in environmental geology and science. The learning activity only takes about two hours of in-class time and an additional three outside of the classroom. It uses simple materials such as a calculator, periodic table, household scale and digital camera. Lessons plans such as these are supported by a grant under the National Science Foundation's Advanced Technological Education (ATE) program.

  18. Supercritical ammonia pretreatment of lignocellulosic materials

    SciTech Connect

    Chou, Y.C.T.; Scott, C.D. (ed.)

    1986-01-01

    A pretreatment technique using ammonia in a supercritical or near-critical fluid state was shown to substantially enhance the susceptibility of polysaccharides in lignocellulosics to subsequent hydrolysis by Trichoderma reesei cellulase. Near-theoretical conversion of cellulose and 70-80% conversion of hemicellulose to sugars from supercritical ammonia pretreated hardwoods or agricultural byproducts were obtained with a small dosage of cellulase. This technique was less effective toward softwoods. The pretreatment results are discussed in light of the properties of supercritical fluids.

  19. YBCO-FET room temperature ammonia sensor

    Microsoft Academic Search

    R. P Gupta; Z Gergintschew; D Schipanski; P. D Vyas

    2000-01-01

    A FET-ammonia sensor operating at room temperature is reported in this paper. The sensor employs a thin film of semiconducting Y:Ba:Cu:O (YBCO) compound, commonly known as 1-2-3 high temperature superconducting cuprate, as its sensing element. We observed that this material is highly and selectively sensitive to ammonia at and below room temperature. The measurements indicate that the non-amplified signal of

  20. Novel Regenerated Solvent Extraction Processes for the Recovery of Carboxylic Acids or Ammonia from Aqueous Solutions Part II. Recovery of Ammonia from Sour Waters

    SciTech Connect

    Poole, L.J.; King, C.J.

    1990-03-01

    Two novel regenerated solvent extraction processes are examined. The first process has the potential to reduce the energy costs inherent in the recovery of low-volatility carboxylic acids from dilute aqueous solutions. The second process has the potential for reducing the energy costs required for separate recovery of ammonia and acid gases (e.g. CO{sub 2} and H{sub 2}S) from industrial sour waters. The recovery of carboxylic acids from dilute aqueous solution can be achieved by extraction with tertiary amines. An approach for regeneration and product recovery from such extracts is to back-extract the carboxylic acid with a water-soluble, volatile tertiary amine, such as trimethylamine. The resulting trimethylammonium carboxylate solution can be concentrated and thermally decomposed, yielding the product acid and the volatile amine for recycle. Experimental work was performed with lactic acid, SUCCiOlC acid, and fumaric acid. Equilibrium data show near-stoichiometric recovery of the carboxylic acids from an organic solution of Alamine 336 into aqueous solutions of trimethylamine. For fumaric and succinic acids, partial evaporation of the aqueous back extract decomposes the carboxylate and yields the acid product in crystalline form. The decomposition of aqueous solutions of trimethylammonium lactates was not carried out to completion, due to the high water solubility of lactic acid and the tendency of the acid to self-associate. The separate recovery of ammonia and acid gases from sour waters can be achieved by combining steam-stripping of the acid gases with simultaneous removal of ammonia by extraction with a liquid cation exchanger. The use of di-2,4,4-trimethylpentyl phosphinic acid as the liquid cation exchanger is explored in this work. Batch extraction experiments were carried out to measure the equilibrium distribution ratio of ammonia between an aqueous buffer solution and an organic solution of the phosphinic acid (0.2N) in Norpar 12. The concentration-based distribution ratios increase from 0.11 to 0.46 as the aqueous phase pH increases from 7.18 to 8.15. Regeneration of the organic extractant solution was carried out by stripping at elevated temperatures to remove the ammonia, with 99% recovery of the ammonia being obtained at 125 C.

  1. Corrosion inhibitor for aqueous ammonia absorption system

    DOEpatents

    Phillips, B.A.; Whitlow, E.P.

    1998-09-22

    A method is described for inhibiting corrosion and the formation of hydrogen and thus improving absorption in an ammonia/water absorption refrigeration, air conditioning or heat pump system by maintaining the hydroxyl ion concentration of the aqueous ammonia working fluid within a selected range under anaerobic conditions at temperatures up to 425 F. This hydroxyl ion concentration is maintained by introducing to the aqueous ammonia working fluid an inhibitor in an amount effective to produce a hydroxyl ion concentration corresponding to a normality of the inhibitor relative to the water content ranging from about 0.015 N to about 0.2 N at 25 C. Also, working fluids for inhibiting the corrosion of carbon steel and resulting hydrogen formation and improving absorption in an ammonia/water absorption system under anaerobic conditions at up to 425 F. The working fluids may be aqueous solutions of ammonia and a strong base or aqueous solutions of ammonia, a strong base, and a specified buffer. 5 figs.

  2. Ammonia--when something smells wrong.

    PubMed

    Makarovsky, Igor; Markel, Gal; Dushnitsky, Tsvika; Eisenkraft, Arik

    2008-07-01

    Ammonia is a common household and industrial chemical. In the medical literature and the electronic press there are many descriptions of accidental spills of anhydrous ammonia, but apart from the Chechen war, there is no evidence of its intentional use by a terrorist to date. When considering its characteristics, ammonia tankers may pose an imminent threat for a civilian population nearby. This short review attempts to highlight the main health issues and basic principles of medical management after exposure to ammonia. Ammonia can directly cause damage due to its irritating as well as alkaline properties. The management of toxic exposure to ammonia is largely supportive and there is no specific antidote. Emergency medical response on site includes rapid evacuation, life-saving procedures and decontamination if necessary and if possible. Major clinical manifestations include respiratory symptoms, such as hypoxia, bronchospasm and pulmonary edema, as well as hypovolemia and burns to the skin and eyes. The immediate medical management consists of life-saving procedures and supportive care, while broad-range antibiotics and systemic corticosteroids may have a role in preventing late onset complications. PMID:18751637

  3. Corrosion inhibitor for aqueous ammonia absorption system

    DOEpatents

    Phillips, Benjamin A. (Benton Harbor, MI); Whitlow, Eugene P. (St. Joseph, MI)

    1998-09-22

    A method of inhibiting corrosion and the formation of hydrogen and thus improving absorption in an ammonia/water absorption refrigeration, air conditioning or heat pump system by maintaining the hydroxyl ion concentration of the aqueous ammonia working fluid within a selected range under anaerobic conditions at temperatures up to 425.degree. F. This hydroxyl ion concentration is maintained by introducing to the aqueous ammonia working fluid an inhibitor in an amount effective to produce a hydroxyl ion concentration corresponding to a normality of the inhibitor relative to the water content ranging from about 0.015 N to about 0.2 N at 25.degree. C. Also, working fluids for inhibiting the corrosion of carbon steel and resulting hydrogen formation and improving absorption in an ammonia/water absorption system under anaerobic conditions at up to 425.degree. F. The working fluids may be aqueous solutions of ammonia and a strong base or aqueous solutions of ammonia, a strong base, and a specified buffer.

  4. Two exactly soluble models of rigidity percolation

    PubMed Central

    Thorpe, M. F.; Stinchcombe, R. B.

    2014-01-01

    We summarize results for two exactly soluble classes of bond-diluted models for rigidity percolation, which can serve as a benchmark for numerical and approximate methods. For bond dilution problems involving rigidity, the number of floppy modes F plays the role of a free energy. Both models involve pathological lattices with two-dimensional vector displacements. The first model involves hierarchical lattices where renormalization group calculations can be used to give exact solutions. Algebraic scaling transformations produce a transition of the second order, with an unstable critical point and associated scaling laws at a mean coordination ?r?=4.41, which is above the ‘mean field’ value ?r?=4 predicted by Maxwell constraint counting. The order parameter exponent associated with the spanning rigid cluster geometry is ?=0.0775 and that associated with the divergence of the correlation length and the anomalous lattice dimension d is d?=3.533. The second model involves Bethe lattices where the rigidity transition is massively first order by a mean coordination ?r?=3.94 slightly below that predicted by Maxwell constraint counting. We show how a Maxwell equal area construction can be used to locate the first-order transition and how this result agrees with simulation results on larger random-bond lattices using the pebble game algorithm. PMID:24379428

  5. Rapid Tunneling and Percolation in the Landscape

    E-print Network

    Sash Sarangi; Gary Shiu; Benjamin Shlaer

    2007-12-21

    Motivated by the possibility of a string landscape, we reexamine tunneling of a scalar field across single/multiple barriers. Recent investigations have suggested modifications to the usual picture of false vacuum decay that lead to efficient and rapid tunneling in the landscape when certain conditions are met. This can be due to stringy effects (e.g. tunneling via the DBI action), or by effects arising due to the presence of multiple vacua (e.g. resonance tunneling). In this paper we discuss both DBI tunneling and resonance tunneling. We provide a QFT treatment of resonance tunneling using the Schr\\"odinger functional approach. We also show how DBI tunneling for supercritical barriers can naturally lead to conditions suitable for resonance tunneling. We argue using basic ideas from percolation theory that tunneling can be rapid in a landscape where a typical vacuum has multiple decay channels and discuss various cosmological implications. This rapidity vacuum decay can happen even if there are no resonance/DBI tunneling enhancements, solely due to the presence of a large number of decay channels. Finally, we consider various ways of circumventing a recent no-go theorem for resonance tunneling in quantum field theory.

  6. Plastics recycling: challenges and opportunities

    PubMed Central

    Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

    2009-01-01

    Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it may be possible to divert the majority of plastic waste from landfills to recycling over the next decades. PMID:19528059

  7. Coal liquefaction with preasphaltene recycle

    DOEpatents

    Weimer, Robert F. (Allentown, PA); Miller, Robert N. (Allentown, PA)

    1986-01-01

    A coal liquefaction system is disclosed with a novel preasphaltene recycle from a supercritical extraction unit to the slurry mix tank wherein the recycle stream contains at least 90% preasphaltenes (benzene insoluble, pyridine soluble organics) with other residual materials such as unconverted coal and ash. This subject process results in the production of asphaltene materials which can be subjected to hydrotreating to acquire a substitute for No. 6 fuel oil. The preasphaltene-predominant recycle reduces the hydrogen consumption for a process where asphaltene material is being sought.

  8. Recycling and Life Cycle Issues

    SciTech Connect

    Das, Sujit [ORNL

    2010-01-01

    This chapter addresses recycling and life cycle considerations related to the growing use of lightweight materials in vehicles. The chapter first addresses the benefit of a life cycle perspective in materials choice, and the role that recycling plays in reducing energy inputs and environmental impacts in a vehicle s life cycle. Some limitations of life cycle analysis and results of several vehicle- and fleet-level assessments are drawn from published studies. With emphasis on lightweight materials such as aluminum, magnesium, and polymer composites, the status of the existing recycling infrastructure and technological challenges being faced by the industry also are discussed.

  9. Lead recycling via rotary furnaces

    SciTech Connect

    Suttie, A.B. [H.J. Enthoven and Sons, Matlock (United Kingdom)

    1995-12-31

    The lead-acid battery recycling industry was seriously affected during the 1980s by increasing environmental protection costs and poor lead prices. The process is now being repeated in the 1990s causing further difficulties for recyclers. In Europe, many lead-acid battery recycling plants use rotary furnaces. The Darley Dale smelter, redeveloped between 1984--87, uses only rotary furnaces. A review of options for this plant has been completed and concluded in favor of further investment to exploit more fully the benefits of rotary furnace technology.

  10. Wastewater Recycle- A Sustainable Approach Towards Desalination

    E-print Network

    Mittal, A.

    2013-01-01

    ? Water scarcity and stringent effluent discharge regulations driving industry towards wastewater recycle. ? Advanced, reliable and energy efficient wastewater treatment and recycle technologies are available to achieve wastewater recycle. ? Energy... and optimizes energy usage in case of ZLD. ? Membrane Bioreactor (MBR) technology in combination with HEROTM can be an economical recycle treatment scheme for refinery and petrochemical wastewater applications. ? Zero Liquid discharge (ZLD) systems, though...

  11. RECYCLE TO EARN Rishi Bhailal Chandra

    E-print Network

    Zhou, Yaoqi

    the motivation to recycle as they don't see any immediate benefits to recycle. IUPUI is setting up single streamRECYCLE TO EARN Rishi Bhailal Chandra Supply Chain Management, Accounting, Kelley School of Business, IUPUI Recycling is a key aspect of any sustainability effort, one that calls

  12. Recycled Wash Water Crushed Returned Concrete

    E-print Network

    1 Recycled Wash Water Crushed Returned Concrete National Concrete Consortium March 2012 Colin Lobo Initiatives Potable water: 10% reduction by 2020 20% reduction by 2030Recycled content: 200% increase b & Solids Management WWW. NRMCA.ORG Recycling Water Challenge: Recycle Water Specification Clauses Mixing

  13. A RECYCLED LAN DSCAPE Richard H. Durrell

    E-print Network

    Maynard, J. Barry

    A RECYCLED LAN DSCAPE by Richard H. Durrell Department of Geology University of Cincinnati Drafting, May 1977 (R.A. Davis, editor) Reprinted 1982 A recycled landscape "Recycling" is the word of the day the same way, Nature recycles even the very hills and valleys beneath our feet. But, as usual, Nature

  14. Ink and Toner Recycling Rewards Program Overview

    E-print Network

    Meyers, Steven D.

    Ink and Toner Recycling Rewards Program Overview www.MyBusinessRecycles.com April 2013 #12;Program Overview · All BSD contract customers can participate in the MyBusinessRecycles program · Customers located in AK, HI or PR are not currently eligible. ­ Education sector customers should join the Recycling Rules

  15. EXPLAINING RURAL HOUSEHOLD PARTICIPATION IN RECYCLING

    Microsoft Academic Search

    Paul M. Jakus; Kelly H. Tiller; William M. Park

    1997-01-01

    Rising landfill costs have forced solid waste managers to consider waste stream reduction alternatives such as household recycling. Explaining the factors which motivate households to recycle is important to regions where households must bear a large portion of the recycling cost because unit-based garbage disposal fees and curbside recycling are not feasible options. Empirical results indicate that residents are responsive

  16. 78 FR 69531 - America Recycles Day, 2013

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    ...by participating in scrap drives and salvage collections...peanuts, and donated old tires in a nationwide push...recycled properly. Recycling not only reduces pollution...let us strive to make recycling a part of our daily...waste-free lunches, recycling programs, and...

  17. The Environment Team to Waste & Recycling

    E-print Network

    St Andrews, University of

    The Environment Team A-Z Guide to Waste & Recycling www.le.ac.uk/environment #12;Welcome ...to the University of Leicester's `A-Z Guide to Waste and Recycling'. Over the last 3 years, the Environment Team has introduced an award- winning recycling scheme across the campus that allows us to recycle paper, plastics

  18. You're a "What"? Recycling Coordinator

    ERIC Educational Resources Information Center

    Torpey, Elka Maria

    2011-01-01

    Recycling coordinators supervise curbside and dropoff recycling programs for municipal governments or private firms. Today, recycling is mandatory in many communities. And advancements in collection and processing methods have helped to increase the quantity of materials for which the recycling coordinator is responsible. In some communities,…

  19. RECYCLING PROGRAM TYPE LOCATION ALLOWED NOT ALLOWED

    E-print Network

    Miami, University of

    RECYCLING PROGRAM TYPE LOCATION ALLOWED NOT ALLOWED Batteries, toner, ink cartridges & cell phones and recycling is an important part of that effort. Below is a guide to on-campus recycling at RSMAS: Visit http://www.rsmas.miami.edu/msgso/ for map of recycling bin locations. NOTE: This is not an exhaustive list. If unauthorized items are found

  20. Waste Toolkit A-Z Battery recycling

    E-print Network

    Melham, Tom

    Waste Toolkit A-Z Battery recycling How can I recycle batteries? The University Safety Office make their own arrangements through a registered hazardous waste carrier. Batteries must not be put in normal waste bins or recycling boxes. To recycle batteries, select either option 1 or 2 below: Option 1

  1. TTUAB PLASTIC RECYCLING PROTOCOL Fall 2011 What Plastic Do We Recycle?

    E-print Network

    Rock, Chris

    TTUAB PLASTIC RECYCLING PROTOCOL ­ Fall 2011 What Plastic Do We Recycle? TTUAB has taken on the responsibility of recycling #1 PET and #2 HDPE plastics by placing a yellow TTUAB Plastic Recycling bin on each recyclables encountered in our bins are ALSO our responsibility (e.g. tin cans, aluminum cans, glass). So

  2. Welcome new and returning residents! Help us make USC greener by recycling! Your Room Recycling Bin

    E-print Network

    Almor, Amit

    Welcome new and returning residents! Help us make USC greener by recycling! Your Room Recycling Bin Every room is provided with a recycling bin to make it easy for you to recycle while living in University Housing. Use this bin to collect mixed recyclables in your room and take them to your nearest

  3. Structure and percolation of one-patch spherocylinders.

    PubMed

    Zhang, Cheng-Yu; Jian, Xing-Liang; Lu, Wei

    2015-02-01

    When the volume fraction exceeds the threshold, the colloidal particles would form a spanning cluster to realize percolation, which is affected by the shape of the particles, interaction between particles, etc. In this paper, we use the Monte Carlo method to study the structure and percolation of a system of one-patch spherocylinders which have been fabricated recently [Chaudhary et al., J. Am. Chem. Soc., 2012, 134, 12901]. With strong adsorption, one-patch spherocylinders self-assemble into multipods which further make contact with each other to form a percolation network at a high volume fraction, while the percolation network is inhibited by the local structures in a system of one-patch spheres. The main multipods are dipods when the patch angle equals ?/3, while they are tetrapods and pentapods when the patch angle equals 2?/3. With enhancing the adsorption, the bigger the patch angle, the more the percolation threshold drops. The orientational order parameter, the distribution of the relative orientation between the nearest neighbors and the probabilities of a spherocylinder owning n adsorbing neighbors have been calculated to analyze the formation and transition of the structures. PMID:25575168

  4. Clustering and percolation in dipolar hard-sphere fluids

    NASA Astrophysics Data System (ADS)

    Laría, Daniel; Vericat, Fernando

    1991-02-01

    Clustering and continuum percolation in dipolar fluids are studied through Monte Carlo simulation and connectedness theory with an emphasis on the effect of the dipole-dipole interactions on the size and shape of the clusters and on the threshold percolation density. Two simple models for the dipolar fluid are considered: (i) a system of hard spheres with an embedded point dipole and (ii) a related system of hard spheres in which the dipole-dipole forces are replaced by an angular-averaged dipolar potential. A first-order perturbation theory (for the first model) and the connectedness version of the Percus-Yevick integral equation (for the second one) are used to describe clustering and percolation, and their results are compared with the corresponding Monte Carlo data. Our results show that clusters become larger in size and acquire a stronger mean dipolar moment when the particles' dipolar moments are increased. Far from the percolation transition, the clusters are nonspherical, the eccentricity being favored by the energetics of dipolar orientation. Furthermore, they reveal that larger dipolar strengths imply smaller percolation densities.

  5. Text recycling: acceptable or misconduct?

    PubMed

    Harriman, Stephanie; Patel, Jigisha

    2014-01-01

    Text recycling, also referred to as self-plagiarism, is the reproduction of an author's own text from a previous publication in a new publication. Opinions on the acceptability of this practice vary, with some viewing it as acceptable and efficient, and others as misleading and unacceptable. In light of the lack of consensus, journal editors often have difficulty deciding how to act upon the discovery of text recycling. In response to these difficulties, we have created a set of guidelines for journal editors on how to deal with text recycling. In this editorial, we discuss some of the challenges of developing these guidelines, and how authors can avoid undisclosed text recycling. PMID:25127654

  6. Make Your Own Recycled Paper

    NSDL National Science Digital Library

    2014-09-18

    Students learn how paper is made. Working together, student teams make their own paper. This activity introduces students to recycling; what it is, its value and benefits, and how it affects their lives.

  7. New approaches to recycling tires

    SciTech Connect

    Spencer, R.

    1991-03-01

    Steel-belted radial tires are potentially one of the most recyclable products created by modern industry, although the potential has been barely tapped. Discarded tires pile up at an astonishing rate each year - 234 million in the US and 26 million passenger tire equivalents in Canada. They represent a mother lode of raw material waiting for modern day miners to transform them into recycled rubber, steel, fiber and energy. The tremendous increase in use of steel belted radials since the early 1970s has complicated their recyclability compared to the bias ply tire, but it has also accomplished waste reduction by tripling tire service life. Part one of this report describes processes being developed to convert tires to crumb rubber, as well as some potential uses of recycled rubber. Part two, to appear next month, will examine such uses as rubberized athletic tracks and highway asphalt.

  8. Disposal, Degradation, and Recycling; Bioplastics

    NSDL National Science Digital Library

    David Teegarden

    2004-01-01

    Everyone is familiar with plastic waste. We throw away large volumes of it, at home, at school, at work, at fast food restaurants, on vacation. Much of it ends up in the trash. We see some of it as litter along the sides of roads, streams and lakes, and floating up on beaches. We probably recycle some used plastics, although how much depends upon where we live. In many localities, only items produced from PET (polyethylene terephthalate) and HDPE (high-density polyethylene) are collected for recycling. Why don't we recycle more of it? Why not LDPE (low-density polyethylene) and polystyrene? And what happens to it when we do? We'll develop some basic principles in this chapter on some of the avenues that help us follow the U.S. Environmental Protection Agency's advice to "reduce, reuse, recycle."

  9. Multi-component removal in flue gas by aqua ammonia

    DOEpatents

    Yeh, James T. (Bethel Park, PA); Pennline, Henry W. (Bethel Park, PA)

    2007-08-14

    A new method for the removal of environmental compounds from gaseous streams, in particular, flue gas streams. The new method involves first oxidizing some or all of the acid anhydrides contained in the gas stream such as sulfur dioxide (SO.sub.2) and nitric oxide (NO) and nitrous oxide (N.sub.2O) to sulfur trioxide (SO.sub.3) and nitrogen dioxide (NO.sub.2). The gas stream is subsequently treated with aqua ammonia or ammonium hydroxide which captures the compounds via chemical absorption through acid-base or neutralization reactions. The products of the reactions can be collected as slurries, dewatered, and dried for use as fertilizers, or once the slurries have been dewatered, used directly as fertilizers. The ammonium hydroxide can be regenerated and recycled for use via thermal decomposition of ammonium bicarbonate, one of the products formed. There are alternative embodiments which entail stoichiometric scrubbing of nitrogen oxides and sulfur oxides with subsequent separate scrubbing of carbon dioxide.

  10. Intra-cluster percolation of calcium signals.

    PubMed

    Solovey, Guillermo; Dawson, Silvina Ponce

    2010-01-01

    Calcium signals are involved in a large variety of physiological processes. Their versatility relies on the diversity of spatiotemporal behaviors that the calcium concentration can display. Calcium entry through inositol 1,4,5-trisphosphate (IP3) receptors (IP3R's) is a key component that participates in both local signals such as "puffs" and in global waves. IP3R's areusually organized in clusters on the membrane of the endoplasmic reticulum and their spatial distribution has important effects on the resulting signal. Recent high resolution observations of Ca2+ puffs offer a window to study intra-cluster organization. The experiments give the distribution of the number of IP3R's that open during each puff without much processing. Here we present a simple model with which we interpret the experimental distribution in terms of two stochastic processes: IP3 binding and unbinding and Ca2+-mediated inter-channel coupling. Depending on the parameters of the system, the distribution may be dominated by one or the other process. The transition between both extreme case sis similar to a percolation process. We show how, from an analysis of the experimental distribution, information can be obtained on the relative weight of the two processes. The largest distance over which Ca2+-mediated coupling acts and the density of IP3-bound IP3R's of the cluster can also be estimated. The approach allows us to infer properties of the interactions among the channels of the cluster from statistical information on their emergent collective behavior. PMID:20174630

  11. Proliferation aspects of plutonium recycling

    Microsoft Academic Search

    Bruno Pellaud

    2002-01-01

    Plutonium recycling offers benefits in an energy perspective of sustainable development, and, moreover it contributes to non-proliferation. Prior to recycling, reactor-grade plutonium from light-water reactors does not lend itself easily to the assembly of explosive nuclear devices; thereafter, practically not at all. Control systems for material security and non-proliferation should identify and adopt several categories of plutonium covering various isotopic

  12. Key recycling in authentication

    E-print Network

    Christopher Portmann

    2014-09-29

    In their seminal work on authentication, Wegman and Carter propose that to authenticate multiple messages, it is sufficient to reuse the same hash function as long as each tag is encrypted with a one-time pad. They argue that because the one-time pad is perfectly hiding, the hash function used remains completely unknown to the adversary. Since their proof is not composable, we revisit it using a composable security framework. It turns out that the above argument is insufficient: if the adversary learns whether a corrupted message was accepted or rejected, information about the hash function is leaked, and after a bounded finite amount of rounds it is completely known. We show however that this leak is very small: Wegman and Carter's protocol is still $\\epsilon$-secure, if $\\epsilon$-almost strongly universal$_2$ hash functions are used. This implies that the secret key corresponding to the choice of hash function can be reused in the next round of authentication without any additional error than this $\\epsilon$. We also show that if the players have a mild form of synchronization, namely that the receiver knows when a message should be received, the key can be recycled for any arbitrary task, not only new rounds of authentication.

  13. Key recycling in authentication

    E-print Network

    Portmann, Christopher

    2012-01-01

    In their seminal work on authentication, Wegman and Carter propose that to authenticate multiple messages, it is sufficient to reuse the same hash function as long as each tag is encrypted with a one-time pad. They argue that because the one-time pad is perfectly hiding, the hash function used remains completely unknown to the adversary. Since their proof is not composable, we revisit it using a universally composable framework. It turns out that the above argument is insufficient: information about the hash function is in fact leaked in every round to the adversary, and after a bounded finite amount of rounds it is completely known. We show however that this leak is very small, and Wegman and Carter's protocol is still \\epsilon-secure, if \\epsilon-almost strongly universal hash functions are used. This implies that the secret key corresponding to the choice of hash function can be recycled for any task without any additional error than this \\epsilon. For example, if all the messages from many rounds of quant...

  14. Novel cellulase recycling method using a combination of Clostridium thermocellum cellulosomes and Thermoanaerobacter brockii ?-glucosidase.

    PubMed

    Waeonukul, Rattiya; Kosugi, Akihiko; Prawitwong, Panida; Deng, Lan; Tachaapaikoon, Chakrit; Pason, Patthra; Ratanakhanokchai, Khanok; Saito, Masayoshi; Mori, Yutaka

    2013-02-01

    This report describes a novel recycling method utilizing a combination of Clostridium thermocellum cellulosomes and Thermoanaerobacter brockii ?-glucosidase (CglT). To recover cellulosomes and CglT through re-binding to additional cellulose, a chimeric CBM3-CglT was created by fusing carbohydrate binding module (CBM3) from the scaffolding protein CipA into the N-terminal region of CglT. When a recycling test using cellulosomes and CBM3-CglT was performed on microcrystalline cellulose, the process was capable of 4 rounds of recycling (1%w/vcellulose/round). Although irreversible absorption of cellulosomes and CBM3-CglT into the residues was observed when ammonia-pretreated rice straw and delignified rice straw was used as substrates, a maximum of 2 and 4 recycling rounds (1%w/vglucan/round) were achieved, respectively, consistent with a 70% saccharification rate. This novel recycling method using cellulosomes and CBM3-CglT has great potential as an effective lignocellulose degradation system. PMID:23313689

  15. The Ammonia?Hydrogen System under Pressure

    SciTech Connect

    Chidester, Bethany A.; Strobel, Timothy A. (CIW)

    2012-01-20

    Binary mixtures of hydrogen and ammonia were compressed in diamond anvil cells to 15 GPa at room temperature over a range of compositions. The phase behavior was characterized using optical microscopy, Raman spectroscopy, and synchrotron X-ray diffraction. Below 1.2 GPa we observed two-phase coexistence between liquid ammonia and fluid hydrogen phases with limited solubility of hydrogen within the ammonia-rich phase. Complete immiscibility was observed subsequent to the freezing of ammonia phase III at 1.2 GPa, although hydrogen may become metastably trapped within the disordered face-centered-cubic lattice upon rapid solidification. For all compositions studied, the phase III to phase IV transition of ammonia occurred at {approx}3.8 GPa and hydrogen solidified at {approx}5.5 GPa, transition pressures equivalent to those observed for the pure components. A P-x phase diagram for the NH{sub 3}-H{sub 2} system is proposed on the basis of these observations with implications for planetary ices, molecular compound formation, and possible hydrogen storage materials.

  16. Energy Efficient Operation of Ammonia Refrigeration Systems

    SciTech Connect

    Mohammed, Abdul Qayyum [University of Dayton, Ohio] [University of Dayton, Ohio; Wenning, Thomas J [ORNL] [ORNL; Sever, Franc [University of Dayton, Ohio] [University of Dayton, Ohio; Kissock, Professor Kelly [University of Dayton, Ohio] [University of Dayton, Ohio

    2013-01-01

    Ammonia refrigeration systems typically offer many energy efficiency opportunities because of their size and complexity. This paper develops a model for simulating single-stage ammonia refrigeration systems, describes common energy saving opportunities, and uses the model to quantify those opportunities. The simulation model uses data that are typically available during site visits to ammonia refrigeration plants and can be calibrated to actual consumption and performance data if available. Annual electricity consumption for a base-case ammonia refrigeration system is simulated. The model is then used to quantify energy savings for six specific energy efficiency opportunities; reduce refrigeration load, increase suction pressure, employ dual suction, decrease minimum head pressure set-point, increase evaporative condenser capacity, and reclaim heat. Methods and considerations for achieving each saving opportunity are discussed. The model captures synergistic effects that result when more than one component or parameter is changed. This methodology represents an effective method to model and quantify common energy saving opportunities in ammonia refrigeration systems. The results indicate the range of savings that might be expected from common energy efficiency opportunities.

  17. Aerobic and anaerobic ammonia production by fish.

    PubMed

    Van Waarde, A

    1983-01-01

    1. In comparison to other vertebrates, a relatively large part of energy consumption in fish is covered by protein catabolism. 2. In Teleosts, ammonia is the major component of nitrogen excretion, its production rate being directly related to the rate of protein oxidation, while urea is almost exclusively produced from nucleotides by uricolysis. 3. Aerobic ammonia excretion arises from extraction of blood ammonia by the gill. 4. Under aerobic conditions, ammonia originates mainly in the liver by transdeamination and the hydrolysis of imino groups, while an additional quantity is formed in working skeletal muscles by purine nucleotide cycling. 5. During a decline of environmental oxygen, the contribution of the liver to total ammonia production seems to be lowered, while that of skeletal muscles is increased. 6. Anaerobic ammoniogenesis seems to proceed via at least 4 different mechanisms, all occurring in goldfish: deamination of adenylates via adenylate deaminase, deamination of aspartate via the purine nucleotide cycle, breakdown of alanine to ethanol, CO2 and NH3, and oxidation of glutamate via a slowly spinning Krebs-cycle. 7. In goldfish, the combination of these mechanisms is able to sustain an anaerobic rate of ammoniogenesis being equal to that observed under normoxic conditions. PMID:6345084

  18. Ammonia-oxidizing archaea have more important role than ammonia-oxidizing bacteria in ammonia oxidation of strongly acidic soils.

    PubMed

    Zhang, Li-Mei; Hu, Hang-Wei; Shen, Ju-Pei; He, Ji-Zheng

    2012-05-01

    Increasing evidence demonstrated the involvement of ammonia-oxidizing archaea (AOA) in the global nitrogen cycle, but the relative contributions of AOA and ammonia-oxidizing bacteria (AOB) to ammonia oxidation are still in debate. Previous studies suggest that AOA would be more adapted to ammonia-limited oligotrophic conditions, which seems to be favored by protonation of ammonia, turning into ammonium in low-pH environments. Here, we investigated the autotrophic nitrification activity of AOA and AOB in five strongly acidic soils (pH<4.50) during microcosm incubation for 30 days. Significantly positive correlations between nitrate concentration and amoA gene abundance of AOA, but not of AOB, were observed during the active nitrification. (13)CO(2)-DNA-stable isotope probing results showed significant assimilation of (13)C-labeled carbon source into the amoA gene of AOA, but not of AOB, in one of the selected soil samples. High levels of thaumarchaeal amoA gene abundance were observed during the active nitrification, coupled with increasing intensity of two denaturing gradient gel electrophoresis bands for specific thaumarchaeal community. Addition of the nitrification inhibitor dicyandiamide (DCD) completely inhibited the nitrification activity and CO(2) fixation by AOA, accompanied by decreasing thaumarchaeal amoA gene abundance. Bacterial amoA gene abundance decreased in all microcosms irrespective of DCD addition, and mostly showed no correlation with nitrate concentrations. Phylogenetic analysis of thaumarchaeal amoA gene and 16S rRNA gene revealed active (13)CO(2)-labeled AOA belonged to groups 1.1a-associated and 1.1b. Taken together, these results provided strong evidence that AOA have a more important role than AOB in autotrophic ammonia oxidation in strongly acidic soils. PMID:22134644

  19. Ammonia-oxidizing archaea have more important role than ammonia-oxidizing bacteria in ammonia oxidation of strongly acidic soils

    PubMed Central

    Zhang, Li-Mei; Hu, Hang-Wei; Shen, Ju-Pei; He, Ji-Zheng

    2012-01-01

    Increasing evidence demonstrated the involvement of ammonia-oxidizing archaea (AOA) in the global nitrogen cycle, but the relative contributions of AOA and ammonia-oxidizing bacteria (AOB) to ammonia oxidation are still in debate. Previous studies suggest that AOA would be more adapted to ammonia-limited oligotrophic conditions, which seems to be favored by protonation of ammonia, turning into ammonium in low-pH environments. Here, we investigated the autotrophic nitrification activity of AOA and AOB in five strongly acidic soils (pH<4.50) during microcosm incubation for 30 days. Significantly positive correlations between nitrate concentration and amoA gene abundance of AOA, but not of AOB, were observed during the active nitrification. 13CO2-DNA-stable isotope probing results showed significant assimilation of 13C-labeled carbon source into the amoA gene of AOA, but not of AOB, in one of the selected soil samples. High levels of thaumarchaeal amoA gene abundance were observed during the active nitrification, coupled with increasing intensity of two denaturing gradient gel electrophoresis bands for specific thaumarchaeal community. Addition of the nitrification inhibitor dicyandiamide (DCD) completely inhibited the nitrification activity and CO2 fixation by AOA, accompanied by decreasing thaumarchaeal amoA gene abundance. Bacterial amoA gene abundance decreased in all microcosms irrespective of DCD addition, and mostly showed no correlation with nitrate concentrations. Phylogenetic analysis of thaumarchaeal amoA gene and 16S rRNA gene revealed active 13CO2-labeled AOA belonged to groups 1.1a-associated and 1.1b. Taken together, these results provided strong evidence that AOA have a more important role than AOB in autotrophic ammonia oxidation in strongly acidic soils. PMID:22134644

  20. Septic wastewater treatment using recycled rubber particles as biofiltration media.

    PubMed

    Oh, Jin Hwan; Park, Jaeyoung; Ellis, Timothy G

    2014-01-01

    Performance of the laboratory-scale recycled rubber particles (RRP) biofilter was compared to a conventional gravel system and a peat biofilter for treatment of septic tank effluent. During the study, the RRP biofilter provided similar or better performance than other systems in terms of organic removal and hydraulic capacity. After the start-up period, RRP biofilter achieved removal efficiencies for BOD5, total suspended solids (TSS), ammonia nitrogen of 96%, 93%, and 90%, respectively, over the range of hydraulic loading rates of 57-204 L/m2/d. On the other hand, the peat biofilter failed hydraulically and the gravel system showed high TSS concentrations in the effluent. RRP provided high surface area and sufficient time for biological treatment. In addition, RRP was observed to provide ammonia adsorption capacity. The results showed that RRP has the potential to be used as substitutes for natural aggregate such as gravel in septic system drainfields. The RRP biofilter can be used as alternative septic systems for the sites where an existing septic system has failed or site conditions, such as high groundwater table or small lot size, are not suitable for the installation of conventional septic systems. PMID:24645443

  1. Loopless non-trapping invasion percolation model for fracking

    E-print Network

    Norris, J Quinn; Rundle, John B

    2014-01-01

    Recent developments in hydraulic fracturing (fracking) have enabled the recovery of large quantities of natural gas and oil from old, low permeability shales. These developments include a change from low-volume, high-viscosity fluid injection to high-volume, low-viscosity injection. The injected fluid introduces distributed damage that provides fracture permeability for the extraction of the gas and oil. In order to model this process, we utilize a loopless non-trapping invasion percolation previously introduced to model optimal polymers in a strongly disordered medium, and for determining minimum energy spanning trees on a lattice. We performed numerical simulations on a 2D square lattice and find significant differences from other percolation models. Additionally, we find that the growing fracture network satisfies both Horton-Strahler and Tokunaga network statistics. As with other invasion percolation models, our model displays burst dynamics, in which the cluster extends rapidly into a connected region. W...

  2. Fast and accurate database searches with MS-GF+Percolator

    SciTech Connect

    Granholm, Viktor; Kim, Sangtae; Navarro, Jose' C.; Sjolund, Erik; Smith, Richard D.; Kall, Lukas

    2014-02-28

    To identify peptides and proteins from the large number of fragmentation spectra in mass spectrometrybased proteomics, researches commonly employ so called database search engines. Additionally, postprocessors like Percolator have been used on the results from such search engines, to assess confidence, infer peptides and generally increase the number of identifications. A recent search engine, MS-GF+, has previously been showed to out-perform these classical search engines in terms of the number of identified spectra. However, MS-GF+ generates only limited statistical estimates of the results, hence hampering the biological interpretation. Here, we enabled Percolator-processing for MS-GF+ output, and observed an increased number of identified peptides for a wide variety of datasets. In addition, Percolator directly reports false discovery rate estimates, such as q values and posterior error probabilities, as well as p values, for peptide-spectrum matches, peptides and proteins, functions useful for the whole proteomics community.

  3. Scaling of clusters near discontinuous percolation transitions in hyperbolic networks

    NASA Astrophysics Data System (ADS)

    Singh, Vijay; Boettcher, Stefan

    2014-07-01

    We investigate the onset of the discontinuous percolation transition in small-world hyperbolic networks by studying the systems-size scaling of the typical largest cluster approaching the transition, p ?pc. To this end, we determine the average size of the largest cluster ˜N? (p) in the thermodynamic limit using real-space renormalization of cluster-generating functions for bond and site percolation in several models of hyperbolic networks that provide exact results. We determine that all our models conform to the recently predicted behavior regarding the growth of the largest cluster, which found diverging, albeit subextensive, clusters spanning the system with finite probability well below pc and at most quadratic corrections to unity in ? (p) for p ?pc. Our study suggests a large universality in the cluster formation on small-world hyperbolic networks and the potential for an alternative mechanism in the cluster formation dynamics at the onset of discontinuous percolation transitions.

  4. Double site-bond percolation model for biomaterial implants

    E-print Network

    Mely, H

    2011-01-01

    We present a double site-bond percolation model to account, on the one hand, for the vascularization and/or resorption of biomaterial implant in bones and, on the other hand, for its mechanical continuity. The transformation of the implant into osseous material, and the dynamical formation/destruction of this osseous material is accounted for by creation and destruction of links and sites in two, entangled, networks. We identify the relevant parameters to describe the implant and its evolution, and separate their biological or chemical origin from their physical one. We classify the various phenomena in the two regimes, percolating or non-percolating, of the networks. We present first numerical results in two dimensions.

  5. An invasion percolation model of drainage network evolution

    NASA Astrophysics Data System (ADS)

    Stark, Colin P.

    1991-08-01

    STREAM networks evolve by headward growth and branching away from escarpments such as rift margins. The structure of these networks and their topographic relief are known to be fractal1-3, but no model so far has been able to generate the observed scaling properties. Here I present a statistical model of network growth in which stream heads branch and propagate at a rate that depends only on the local strength of the substrate. This model corresponds to the process of invasion percolation4, with the added requirement of self-avoidance; it is a self-organized critical system5 with properties similar to those of standard percolation models6. A description based on self-avoiding invasion percolation reproduces the known scaling behaviour of stream networks, and may provide a valuable tool for delineation of drainage patterns from digital topographic data sets7,8.

  6. Scaling behavior of explosive percolation on the square lattice

    NASA Astrophysics Data System (ADS)

    Ziff, Robert M.

    2010-11-01

    Clusters generated by the product-rule growth model of Achlioptas, D’Souza, and Spencer on a two-dimensional square lattice are shown to obey qualitatively different scaling behavior than standard (random growth) percolation. The threshold with unrestricted bond placement (allowing loops) is found precisely using several different criteria based on both moments and wrapping probabilities, yielding pc=0.526565±0.000005 , consistent with the recent result of Radicchi and Fortunato. The correlation-length exponent ? is found to be close to 1. The qualitative difference from regular percolation is shown dramatically in the behavior of the percolation probability P? (size of largest cluster), of the susceptibility, and of the second moment of finite clusters, where discontinuities appear at the threshold. The critical cluster-size distribution does not follow a consistent power law for the range of system sizes we study (L?8192) but may approach a power law with ?>2 for larger L .

  7. Percolation of dimers irreversibly adsorbed on heterogeneous surfaces

    NASA Astrophysics Data System (ADS)

    Gimenez, M. C.; Ramirez-Pastor, A. J.

    2015-03-01

    The percolation problem of irreversibly deposited dimers on square lattices with two kinds of sites is studied. Simple adsorptive surfaces are generated by square patches of l × l sites, which can be either arranged in a deterministic chessboard structure or in a random way. Thus, the system can be characterized by the distribution (ordered or random) of the patches, the patch size l and the probability of occupying each patch ?i (i = 1 , 2). Dimers (particles that occupy two neighboring sites simultaneously) are irreversibly adsorbed on the lattice. By means of random adsorption simulations and finite-size scaling analysis, a complete (?1-?2- l) phase diagram separating a percolating and a non-percolating region is determined.

  8. Poly(N-vinyl-2-pyrrolidone)-stabilized palladium-platinum nanoparticles-catalyzed hydrolysis of ammonia borane for hydrogen generation

    NASA Astrophysics Data System (ADS)

    Rakap, Murat

    2015-02-01

    The catalytic use of highly efficient poly(N-vinyl-2-pyrrolidone)-stabilized palladium-platinum nanoparticles (4.2 ± 1.9 nm) in the hydrolysis of ammonia-borane is reported. The catalyst is prepared by co-reduction of two metal ions in ethanol/water mixture by an alcohol reduction method and characterized by transmission electron microscopy, X-ray photoelectron spectroscopy and UV-Vis spectroscopy. They are recyclable and highly active for hydrogen generation from the hydrolysis of ammonia-borane even at very low concentrations and temperature, providing a record numbers of average turnover frequency value (125 mol H2/mol cat.min-1) and maximum hydrogen generation rate (3468 L H2 min-1 (mol cat)-1). They also provide activation energy of 51.7 ± 2 kJ/mol for the hydrolysis of ammonia borane.

  9. Effectiveness of porous covers for control of ammonia, reduced sulfur compounds, total hydrocarbons, selected volatile organic compounds, and odor from hog manure storage lagoons.

    PubMed

    Regmi, Shekhar; Ongwandee, Maneerat; Morrison, Glenn; Fitch, Mark; Surampalli, Rao

    2007-06-01

    Anaerobic lagoons are a major source of odor at concentrated animal feeding operations. Seven different kinds of artificial (geotextile and polyethylene foam) and natural (straw and redwood) permeable lagoon covers were evaluated for their potential to reduce odorous emissions generated by anaerobic waste lagoons. A novel floating sampling raft was constructed and used to simultaneously evaluate the effectiveness of lagoon covers on an operating swine waste lagoon. The air collected from the raft was evaluated for odor, total reduced sulfur (TRS) compounds, ammonia, total hydrocarbons, dimethyldisulfide, and trimethylamine. The emission rates from the lagoon were highly variable both temporally and spatially. All of the lagoon covers substantially reduced TRS emissions and odor. Geotextile fabric and a recycled foam cover exhibited the greatest reduction in total hydrocarbon emissions; natural covers were less effective. Because of consistently low emission rates of ammonia, no statistically significant reduction of ammonia emissions were observed from any of the lagoon covers. PMID:17608010

  10. The static electrical conductivity of water-in-oil microemulsions below percolation threshold

    NASA Astrophysics Data System (ADS)

    Bordi, F.; Cametti, C.; Chen, S. H.; Rouch, J.; Sciortino, F.; Tartaglia, P.

    1996-02-01

    We study the static electric conductivity in water-in-oil microemulsion systems both in the droplet phase and in the vicinity of a percolation transition in the non-percolating region. We discuss the mechanisms of conduction in the two regimes. In particular, we interpret the behavior of conductivity far from percolation in terms of charge fluctuations and close to percolation in terms of collection of relaxation times connected to the presence of a polydisperse set of independent fractal clusters.

  11. 50 Simple Things Kids Can Do To Recycle. California Edition.

    ERIC Educational Resources Information Center

    Javna, John

    This book provides 50 recycling ideas for children and features Recycle Rex, the state of California's "spokesdinosaur" for recycling. An introduction contains recycling background information on waste disposal options and reducing, reusing, and recycling. Recycling suggestions are divided into nine sections: (1) "Learn What You Can Recycle"…

  12. RDS and Recycling Waste Diversion in Food Prep

    E-print Network

    Awtar, Shorya

    RDS and Recycling Waste Diversion in Food Prep Setting #12;Why Recycle? Recycling saves resources Recycling one ton of paper saves 17 trees! Recycling saves energy Recycling one aluminum can saves enough energy to power a television for 3 hours! Recycling is easy There are 4 waste categories here at UM

  13. 1. Recycle all bottles and cans 2. Recycle all personal electronics

    E-print Network

    Howitt, Ivan

    RECYCLING 1. Recycle all bottles and cans 2. Recycle all personal electronics 3. Bring your own PREVENTION 32. Dispose of all cigarette butts properly 33. Use cloth napkins as much as possible 34. Reuse

  14. Combustion Byproducts Recycling Consortium

    SciTech Connect

    Paul Ziemkiewicz; Tamara Vandivort; Debra Pflughoeft-Hassett; Y. Paul Chugh; James Hower

    2008-08-31

    The Combustion Byproducts Recycling Consortium (CBRC) program was developed as a focused program to remove and/or minimize the barriers for effective management of over 123 million tons of coal combustion byproducts (CCBs) annually generated in the USA. At the time of launching the CBRC in 1998, about 25% of CCBs were beneficially utilized while the remaining was disposed in on-site or off-site landfills. During the ten (10) year tenure of CBRC (1998-2008), after a critical review, 52 projects were funded nationwide. By region, the East, Midwest, and West had 21, 18, and 13 projects funded, respectively. Almost all projects were cooperative projects involving industry, government, and academia. The CBRC projects, to a large extent, successfully addressed the problems of large-scale utilization of CCBs. A few projects, such as the two Eastern Region projects that addressed the use of fly ash in foundry applications, might be thought of as a somewhat smaller application in comparison to construction and agricultural uses, but as a novel niche use, they set the stage to draw interest that fly ash substitution for Portland cement might not attract. With consideration of the large increase in flue gas desulfurization (FGD) gypsum in response to EPA regulations, agricultural uses of FGD gypsum hold promise for large-scale uses of a product currently directed to the (currently stagnant) home construction market. Outstanding achievements of the program are: (1) The CBRC successfully enhanced professional expertise in the area of CCBs throughout the nation. The enhanced capacity continues to provide technology and information transfer expertise to industry and regulatory agencies. (2) Several technologies were developed that can be used immediately. These include: (a) Use of CCBs for road base and sub-base applications; (b) full-depth, in situ stabilization of gravel roads or highway/pavement construction recycled materials; and (c) fired bricks containing up to 30%-40% F-fly ash. Some developed technologies have similar potential in the longer term. (3) Laboratory studies have been completed that indicate that much higher amounts of fly ash could be added in cement-concrete applications under some circumstances. This could significantly increase use of fly ash in cement-concrete applications. (4) A study of the long-term environmental effects of structural fills in a surface mine in Indiana was completed. This study has provided much sought after data for permitting large-volume management options in both beneficial as well as non-beneficial use settings. (5) The impact of CBRC on CCBs utilization trends is difficult to quantify. However it is fair to say that the CBRC program had a significant positive impact on increased utilization of CCBs in every region of the USA. Today, the overall utilization of CCBs is over 43%. (6) CBRC-developed knowledge base led to a large number of other projects completed with support from other sources of funding. (7) CBRC research has also had a large impact on CCBs management across the globe. Information transfer activities and visitors from leading coal producing countries such as South Africa, Australia, England, India, China, Poland, Czech Republic and Japan are truly noteworthy. (8) Overall, the CBRC has been a truly successful, cooperative research program. It has brought together researchers, industry, government, and regulators to deal with a major problem facing the USA and other coal producing countries in the world.

  15. Deep Recycling of Carbon

    NASA Astrophysics Data System (ADS)

    Schmidt, M. W.

    2012-12-01

    While most of the subducted H2O is recycled at shallow and subarc depths, carbon is less readily mobilized and susceptive to complex redox processes involving CO2 in solids, fluids and melts, elemental carbon, Fe- and Si- carbides, and methane. Here I review the various ways of recycling carbon during subduction and present a spectrum of possible reaction products in the mantle. Metamorphic reactions liberate <20% of the subducted CO2 to the subarc region (Connolly 2005, EPSL). Larger amounts might be mobilized through (sediment) melting. Although the wet pelite solidus is only shifted by 30-50 oC (at 3 GPa) with carbonates, the latter remain stable with melts that are saturated in a H2O+CO2-fluid. Complete dissolution of carbonates requires temperatures above any predicted subduction geotherm. Carbonated sediments yield CO2-rich phonolites to 5 GPa but carbonatites at higher pressures. The silicate melts become increasingly potassic with pressure, while the alkali-rich carbonatites have their highest K/Na at 8 GPa, slightly decreasing to 13 GPa and become sodic with the disappearance of residual cpx at ~16 GPa. What may happen when carbonated pelite derived melts migrate into the mantle is illustrated in Central Italy: in this case, it can be experimentally demonstrated that hybridization of ultrapotassic phonolitic melts with ~2 wt% H2O and ~6 wt% CO2 in the mantle results in the primitive parents of the ultrapotassic kamafugite suites which have ~43 wt% SiO2. Hence, despite a crustal isotopic signature of C, O, and Sr in these rocks, the CO2 of the Italian magmatism does not stem from assimilation in the crust but from melts derived from subducted marine carbonates mixed with pelagic clays and then reacted in the mantle. The migration of CO2-bearing fluids and melts into the mantle may lead to a redox-shock. Where high liquid/mantle ratios prevail, carbonatites rest in their oxidized form and may only freeze in relatively cold lithospheric keels where they form metasomatic zones prone to generate kimberlites in the context of a much later remelting event. Where the redox-capacity of the oxidized crust-derived material is subequal to the reduced mantle, iron carbides are to be expected. The eutectic in the Fe-Ni-C system is at lower temperatures than the mantle adiabat, leading to the distinct possibility that such zones entrained in global mantle convection will contain ~1% of eutectic Fe-C-melt. When the amount of subduction derived CO2 is small compared to the redox capacity of a metal bearing reduced mantle, diamond will form, but diamond itself is not truly reducing at high pressures. The most extreme reducing case leads to moissanite (found together with diamond), which isotopic signature implies involvement of organically derived carbon. Moissanite (SiC) only forms at fO2 <6-8 log units below iron-wustite and coexists with mantle silicates that have an XMg of 0.995-0.998. Our calculations show that a fluid or melt with a bulk, which is slightly more reduced than the CO2-H2O-tieline in C-O-H, may evolve to ultra-reduced residual C-H-rich fluids through removal of CO2 (through carbonate precipitation) followed by removal of H2O (through hydrous silicate formation). As SiC may only be in grain scale equilibrium with the mantle and requires a protracted fluid-fractionation, we propose that SiC is generally a low temperature phase formed from originally already reducing fluids involving organic carbon and hence subduction.

  16. Rethinking Recycling in Arcs

    NASA Astrophysics Data System (ADS)

    Kelemen, P.; Behn, M. D.; Jagoutz, O.

    2012-12-01

    Hacker et al EPSL 2011 and Behn et al Nature Geosci 2011 investigated pathways for return of buoyant, subducted material to arc crust. These include (1) diapirs rising into the hot mantle wedge, with extensive melts adding a component to arc magmas, (2) flow of material back up a relatively cold "subduction channel", adding solids to the lower crust and small-degree partial melts to the upper crust, (3) flow from the forearc along the base of arc crust, and (4) imbrication of forearc material into arc crust. These processes add felsic, incompatible-element-rich components to arc crust. The flux of incompatible elements such as Th in arc lavas, thought to be mainly recycled from subducted sediments, is > sediment subduction flux. There are large uncertainties: arc crustal growth rates are imprecise; young, primitive arc lavas may not be representative of magmatic flux into arc crust; sediment subduction flux may have varied. Nevertheless, this result is found for all arcs examined, using recently published growth rates. Perhaps arc growth rates that include subduction erosion are systematically overestimated. Instead or in addition, maybe significant Th comes from material other than sediments. Here, we consider the implications of pathways 1-4 for arc growth rates and incompatible element enrichment, in the context of subduction erosion and arc-arc collision. Subducting arc lithologies can become separated, with only felsic components returned to arc crust. Buoyant lithologies are mobile in viscous instabilities at > 700-800°C. Whereas thin layers such as sediments may become mobile all at once, instabilities may periodically strip the hottest parts from the top of thick buoyant layers, replacing them with hot mantle. In arc-arc collision, the top of a subducting plate starts at about 0°C on the seafloor, so heating is slow. In subduction erosion, forearc material in the subducting package can be > 200°C before erosion so buoyant lithologies reach 700-800°C faster, and in larger volumes at a given time. Subduction erosion rarely, if ever, transports significant amounts of buoyant material deep into the convecting mantle. Because buoyant material can remain part of the crust, it may often be a mistake to add all of the eroded material to the observed arc volume to derive crustal growth rates. Buoyancy instabilities during subduction erosion or arc-arc collision will accumulate felsic arc crust. For example, > 50% of Aleutian arc lavas and exposed plutons are more buoyant than mantle peridotite at 700-800°C, 3-4 GPa. The buoyant material has an average of 60-62 wt% SiO2, molar Mg/(Mg+Fe) 0.4-0.5, and trace elements identical to bulk continental crust, though western Aleutian lavas have the most depleted Sr, Nd and Pb isotope ratios of all arc lavas worldwide. In general, density sorting of arc lithologies, and subsequent partial melting as buoyant rocks rise through the mantle wedge or along a subduction channel, could lead to a kind of double and triple distillation. Incompatible elements such as Th would be enriched in arc crust, retaining correlations with isotopic indicators of a recycled sediment component, while Th-poor, dense, mafic lavas and lower crustal cumulates return to the convecting mantle.

  17. The reaction of monochloramine and hydroxylamine: implications for ammonia?oxidizing bacteria in chloraminated drinking water

    EPA Science Inventory

    Drinking water chloramine use may promote ammonia?oxidizing bacteria (AOB) growth because of naturally occurring ammonia, residual ammonia remaining from chloramine formation, and ammonia released from chloramine decay and demand. A rapid chloramine residual loss is often associa...

  18. Directed compact percolation near a damp wall with biased growth

    NASA Astrophysics Data System (ADS)

    Lonsdale, H.; Owczarek, A. L.

    2012-11-01

    The model of directed compact percolation near a damp wall is generalized to allow for a bias in the growth of a cluster, either towards or away from the wall. The percolation probability for clusters beginning with seed width m, any distance from the wall, is derived exactly by solving the associated recurrences. It is found that the general biased case near a damp wall leads to a critical exponent ? = 1, in line with the dry biased case, which differs from the unbiased damp/dry exponent ? = 2.

  19. Remnant percolative disorder in highly-cured networks

    SciTech Connect

    Adolf, D.; Hance, B.; Martin, J.E. (Sandia National Labs., Albuquerque, NM (United States))

    1993-05-24

    The authors have previously reported viscoelastic measurements demonstrating that fully-cured networks and critical gels exhibit similar relaxation spectra, implying that fully-cured networks are somewhat ill- connected. Here, they present restricted valence percolation simulations of networks well beyond the percolation transition that explicitly display remnant disorder over length scales less than the correlation length of the network. They conclude that the topology of highly-cured networks is not well described by a regular three- dimensional tennis net but is ill-connected over length scales that correspond to relaxation modes of practical interest.

  20. Roughness of Brittle Fractures as a Correlated Percolation Problem

    NASA Astrophysics Data System (ADS)

    Bakke, Jan Øystein H.; Bjelland, Johannes; Ramstad, Thomas; Stranden, Torunn; Hansen, Alex; Schmittbuhl, Jean

    This paper is dedicated to Professor Dietrich Stauffer on the occasion of his sixtieth birthday. The morphology of brittle fracture surfaces are self affine with roughness exponents that may be classified into a small number of universality classes. We discuss these in light of the recent proposal that the self affinity is a manifestation of the fracture process being a correlated percolation process. We also study numerically with high precision the roughness exponent in the two-dimensional fuse model with disorder both in breaking thresholds and conductances of the fuses. Our results are consistent with the predictions of the correlated percolation theory.

  1. Scaling theory for percolative charge transport in disordered molecular semiconductors.

    PubMed

    Cottaar, J; Koster, L J A; Coehoorn, R; Bobbert, P A

    2011-09-23

    We present a scaling theory for charge transport in disordered molecular semiconductors that extends percolation theory by including bonds with conductances close to the percolating one in the random-resistor network representing charge hopping. A general and compact expression is given for the charge mobility for Miller-Abrahams and Marcus hopping on different lattices with Gaussian energy disorder, with parameters determined from numerically exact results. The charge-concentration dependence is universal. The model-specific temperature dependence can be used to distinguish between the hopping models. PMID:22026880

  2. Construction of the incipient infinite cluster for spreadout oriented percolation above 4 + 1 dimensions

    E-print Network

    Slade, Gordon

    Construction of the incipient infinite cluster for spread­out oriented percolation above 4 + 1 the incipient infinite cluster measure (IIC) for su#ciently spread­out ori­ ented percolation on Z d × Z in a previous paper to relate critical oriented percolation to super­Brownian motion, for d + 1 > 4 + 1. 1

  3. Construction of the incipient infinite cluster for spread-out oriented percolation above 4 + 1 dimensions

    E-print Network

    Hofstad, Remco van der

    Construction of the incipient infinite cluster for spread-out oriented percolation above 4 + 1 the incipient infinite cluster measure (IIC) for sufficiently spread-out ori- ented percolation on Zd × Z paper to relate critical oriented percolation to super-Brownian motion, for d + 1 > 4 + 1. 1

  4. ON THE TIME CONSTANT IN A DEPENDENT FIRST PASSAGE PERCOLATION MODEL

    E-print Network

    Boyer, Edmond

    ON THE TIME CONSTANT IN A DEPENDENT FIRST PASSAGE PERCOLATION MODEL JULIE SCHOLLER Abstract. We pursue the study of a random coloring first passage percolation model introduced by Fontes and Newman. We prove that the asymptotic shape of this first passage percolation model continuously depends on the law

  5. Environmental and economic assessment of a cracked ammonia fuelled alkaline fuel cell for off-grid power applications

    NASA Astrophysics Data System (ADS)

    Cox, Brian; Treyer, Karin

    2015-02-01

    Global mobile telecommunication is possible due to millions of Base Transceiver Stations (BTS). Nearly 1 million of these are operating off-grid, typically powered by diesel generators and therefore leading to significant CO2 emissions and other environmental burdens. A novel type of Alkaline Fuel Cell (AFC) powered by cracked ammonia is being developed for replacement of these generators. This study compares the environmental and economic performance of the two systems by means of Life Cycle Assessment (LCA) and Levelised Cost of Electricity (LCOE), respectively. Results show that the production of ammonia dominates the LCA results, and that renewable ammonia production pathways greatly improve environmental performance. Sensitivity analyses reveal that the fuel cell parameters that most affect system cost and environmental burdens are cell power density and lifetime and system efficiency. Recycling of anode catalyst and electrode substrate materials is found to have large impacts on environmental performance, though without large cost incentives. For a set of target parameter values and fossil sourced ammonia, the AFC is calculated to produce electricity with life cycle CO2 eq emissions of 1.08 kg kWh-1, which is 23% lower than a diesel generator with electricity costs that are 14% higher in the same application.

  6. What can recycling in thermal reactors accomplish?

    SciTech Connect

    Piet, Steven J.; Matthern, Gretchen E.; Jacobson, Jacob J. [Idaho National Laboratory - INL, 2525 N. Fremont Avenue, Idaho Falls, ID 83415 (United States)

    2007-07-01

    Thermal recycle provides several potential benefits when used as stop-gap, mixed, or backup recycling to recycling in fast reactors. These three roles involve a mixture of thermal and fast recycling; fast reactors are required to some degree at some time. Stop-gap uses thermal reactors only until fast reactors are adequately deployed and until any thermal-recycle-only facilities have met their economic lifetime. Mixed uses thermal and fast reactors symbiotically for an extended period of time. Backup uses thermal reactors only if problems later develop in the fast reactor portion of a recycling system. Thermal recycle can also provide benefits when used as pure thermal recycling, with no intention to use fast reactors. However, long term, the pure thermal recycling approach is inadequate to meet several objectives. (authors)

  7. What can Recycling in Thermal Reactors Accomplish?

    SciTech Connect

    Steven Piet; Gretchen E. Matthern; Jacob J. Jacobson

    2007-09-01

    Thermal recycle provides several potential benefits when used as stop-gap, mixed, or backup recycling to recycling in fast reactors. These three roles involve a mixture of thermal and fast recycling; fast reactors are required to some degree at some time. Stop-gap uses thermal reactors only until fast reactors are adequately deployed and until any thermal-recycle-only facilities have met their economic lifetime. Mixed uses thermal and fast reactors symbiotically for an extended period of time. Backup uses thermal reactors only if problems later develop in the fast reactor portion of a recycling system. Thermal recycle can also provide benefits when used as pure thermal recycling, with no intention to use fast reactors. However, long term, the pure thermal recycling approach is inadequate to meet several objectives.

  8. Biochemistry of Ammonia Monoxygenase from Nitrosomonas

    SciTech Connect

    Alan Hooper

    2009-07-15

    Major results. 1. CytochromecM552, a protein in the electron transfer chain to ammonia monooxygenase. Purification, modeling of protein structure based on primary structure, characterization of 4 hemes by magnetic spectroscopy, potentiometry, ligand binding and turnover. Kim, H. J., ,Zatsman, et al. 2008). 2. Characterization of proteins which thought to be involved in the AMO reaction or to protect AMO from toxic nitrogenous intermediates such as NO. Nitrosocyanin is a protein present only in bacteria which catalyze the ammonia monoxygenase reaction (1). Cytochrome c P460 beta and cytochrome c’ beta.

  9. Ammonia Results Review for Retained Gas Sampling

    SciTech Connect

    Mahoney, Lenna A.

    2000-09-20

    This report was prepared as part of a task supporting the deployment of the retained gas sampler (RGS) system in Flammable Gas Watch List Tanks. The emphasis of this report is on presenting supplemental information about the ammonia measurements resulting from retained gas sampling of Tanks 241-AW-101, A-101, AN-105, AN-104, AN-103, U-103, S-106, BY-101, BY-109, SX-106, AX-101, S-102, S-111, U-109, and SY-101. This information provides a better understanding of the accuracy of past RGS ammonia measurements, which will assist in determining flammable and toxicological hazards.

  10. DWPF Recycle Evaporator Simulant Tests

    SciTech Connect

    Stone, M

    2005-04-05

    Testing was performed to determine the feasibility and processing characteristics of an evaporation process to reduce the volume of the recycle stream from the Defense Waste Processing Facility (DWPF). The concentrated recycle would be returned to DWPF while the overhead condensate would be transferred to the Effluent Treatment Plant. Various blends of evaporator feed were tested using simulants developed from characterization of actual recycle streams from DWPF and input from DWPF-Engineering. The simulated feed was evaporated in laboratory scale apparatus to target a 30X volume reduction. Condensate and concentrate samples from each run were analyzed and the process characteristics (foaming, scaling, etc) were visually monitored during each run. The following conclusions were made from the testing: Concentration of the ''typical'' recycle stream in DWPF by 30X was feasible. The addition of DWTT recycle streams to the typical recycle stream raises the solids content of the evaporator feed considerably and lowers the amount of concentration that can be achieved. Foaming was noted during all evaporation tests and must be addressed prior to operation of the full-scale evaporator. Tests were conducted that identified Dow Corning 2210 as an antifoam candidate that warrants further evaluation. The condensate has the potential to exceed the ETP WAC for mercury, silicon, and TOC. Controlling the amount of equipment decontamination recycle in the evaporator blend would help meet the TOC limits. The evaporator condensate will be saturated with mercury and elemental mercury will collect in the evaporator condensate collection vessel. No scaling on heating surfaces was noted during the tests, but splatter onto the walls of the evaporation vessels led to a buildup of solids. These solids were difficult to remove with 2M nitric acid. Precipitation of solids was not noted during the testing. Some of the aluminum present in the recycle streams was converted from gibbsite to aluminum oxide during the evaporation process. The following recommendations were made: Recycle from the DWTT should be metered in slowly to the ''typical'' recycle streams to avoid spikes in solids content to allow consistent processing and avoid process upsets. Additional studies should be conducted to determine acceptable volume ratios for the HEME dissolution and decontamination solutions in the evaporator feed. Dow Corning 2210 antifoam should be evaluated for use to control foaming. Additional tests are required to determine the concentration of antifoam required to prevent foaming during startup, the frequency of antifoam additions required to control foaming during steady state processing, and the ability of the antifoam to control foam over a range of potential feed compositions. This evaluation should also include evaluation of the degradation of the antifoam and impact on the silicon and TOC content of the condensate. The caustic HEME dissolution recycle stream should be neutralized to at least pH of 7 prior to blending with the acidic recycle streams. Dow Corning 2210 should be used during the evaporation testing using the radioactive recycle samples received from DWPF. Evaluation of additional antifoam candidates should be conducted as a backup for Dow Corning 2210. A camera and/or foam detection instrument should be included in the evaporator design to allow monitoring of the foaming behavior during operation. The potential for foam formation and high solids content should be considered during the design of the evaporator vessel.

  11. Diffusion of ammonia gas in PDMS characterized by ATR spectroscopy

    NASA Astrophysics Data System (ADS)

    Levinský, Petr; Kalvoda, Ladislav; Aubrecht, Jan; Fojtíková, Jaroslava

    2015-01-01

    The kinetic parameters of a chemo-optical transducer layer sensitive to gaseous ammonia are characterized by means of attenuation total reflection method. The tested layer consists of cross-linked polydimethylsiloxane matrix sensitized by quinoline-based organometallic dye showing the selective chemical reaction with ammonia. Upper and lower limits of the ammonia diffusion coefficient and the ammonia-dye reaction constant are derived from the obtained experimental data and compared with other data available in literature and obtained from computer simulations.

  12. Recycling of polymers: a review.

    PubMed

    Ignatyev, Igor A; Thielemans, Wim; Vander Beke, Bob

    2014-06-01

    Plastics are inexpensive, easy to mold, and lightweight. These and many other advantages make them very promising candidates for commercial applications. In many areas, they have substantially suppressed traditional materials. However, the problem of recycling still is a major challenge. There are both technological and economic issues that restrain the progress in this field. Herein, a state-of-art overview of recycling is provided together with an outlook for the future by using popular polymers such as polyolefins, poly(vinyl chloride), polyurethane, and poly(ethylene terephthalate) as examples. Different types of recycling, primary, secondary, tertiary, quaternary, and biological recycling, are discussed together with related issues, such as compatibilization and cross-linking. There are various projects in the European Union on research and application of these recycling approaches; selected examples are provided in this article. Their progress is mirrored by granted patents, most of which have a very limited scope and narrowly cover certain technologies. Global introduction of waste utilization techniques to the polymer market is currently not fully developed, but has an enormous potential. PMID:24811748

  13. Radioactive materials in recycled metals.

    PubMed

    Lubenau, J O; Yusko, J G

    1995-04-01

    In recent years, the metal recycling industry has become increasingly aware of an unwanted component in metal scrap--radioactive material. Worldwide, there have been 35 instances where radioactive sources were unintentionally smelted in the course of recycling metal scrap. In some cases contaminated metal consumer products were distributed internationally. In at least one case, serious radiation exposures of workers and the public occurred. Radioactive material appearing in metal scrap includes sources subject to licensing under the Atomic Energy Act and also naturally occurring radioactive material. U.S. mills that have smelted a radioactive source face costs resulting from decontamination, waste disposal, and lost profits that range from 7 to 23 million U.S. dollars for each event. To solve the problem, industry and the government have jointly undertaken initiatives to increase awareness of the problem within the metal recycling industry. Radiation monitoring of recycled metal scrap is being performed increasingly by mills and, to a lesser extent, by scrap processors. The monitoring does not, however, provide 100% protection. Improvements in regulatory oversight by the government could stimulate improved accounting and control of licensed sources. However, additional government effort in this area must be reconciled with competing priorities in radiation safety and budgetary constraints. The threat of radioactive material in recycled metal scrap will continue for the foreseeable future and, thus, poses regulatory policy challenges for both developed and developing nations. PMID:7883556

  14. The McGraw-Hill recycling handbook

    SciTech Connect

    Lund, H.F.

    1992-01-01

    This reference begins with an overview of recycling, federal, local and state legislation, municipal and commercial waste streams, setting recycling priorities, separation and collection systems, processing facilities, marketing problems and solutions, public awareness programs, and the psychology of recycling. The second section covers recyclable materials, providing information on collection, processing, transportation, marketing, new product potential, and costs. The book offers details on facility design and recycling equipment, and a section on the implementation and control of recycling. Extensive appendixes, a glossary, and an index are included.

  15. USE OF ZEOLITE FOR REMOVING AMMONIA AND AMMONIA-CAUSED TOXCITY IN MARINE TOXICITY IDENTIFCATION EVALUATIONS (TIES)

    EPA Science Inventory

    Ammonia occurs in marine waters including effluents, receiving waters, and sediment interstitial waters. At sufficiently high concentrations, ammonia can be toxic to aquatic species. Toxicity identification evaluation (TIE) methods provide researchers with tools for identifyi...

  16. TOXICITY OF AMMONIA, NITRITE AND NITRATE TO FISHES

    EPA Science Inventory

    Ammonia and nitrite are highly toxic to fishes, wig ammonia occurring in urface waters more commonly than nitrite. itrate is a related compound but is not ignificantly toxic to fishes. he acute toxicity of ammonia to aquatic organisms s affected by water pH, dissolved oxygen, tem...

  17. EVALUATION OF AMMONIA 'FIXATION' COMPONENTS IN ACTUAL REFINERY SOUR WATERS

    EPA Science Inventory

    High ammonia concentrations (fixed ammonia) in stripped sour waters from petroleum refining are caused by weak organic acids and both weak and strong sulfur acids. The sulfur acids result from oxidation of sulfides present in sour water. Fixed ammonia can be eliminated by adding ...

  18. Comparison of ammonia emissions determined using different sampling methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dynamic, flow-through flux chambers are sometimes used to estimate ammonia emissions from livestock operations; however, ammonia emissions from the surfaces are affected by many factors which can be affected by the chamber. Ammonia emissions estimated using environmental flow-through chambers may be...

  19. MANAGEMENT OPTIONS FOR REDUCING AMMONIA EMISSIONS FROM POULTRY LITTER

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia emissions from poultry litter not only result in air pollution; high levels of ammonia in poultry houses cause poor bird performance, increase the susceptibility of birds to viral diseases, and negatively impact human health. Although ammonia emissions are a concern, few cost-effective best ...

  20. Physiology and Diversity of Ammonia-Oxidizing Archaea

    E-print Network

    de la Torre, José R.

    -4227/12/1013-0083$20.00 Keywords Thaumarchaeota, ammonia oxidation, nitrification, nitrogen cycle Abstract The discovery of ammonia atom of molecular oxygen into its substrate as a hydroxyl group AOB: ammonia- oxidizing bacteria MMO. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 A BRIEF HISTORY OF DISCOVERY

  1. Temperature dependence of feedyard ammonia emissions: The Arrhenius equation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia emissions from beef cattle feedyards exhibit an annual pattern-like temperature. This suggests that ammonia emissions may obey the Arrhenius temperature relationship. Our objective was to determine the Arrhenius relationship between mean monthly ammonia emissions from cattle feedyards and me...

  2. A SENSITIVE AND AFFORDABLE COMPACT AMMONIA MONITOR - PHASE I

    EPA Science Inventory

    Ammonia has an important role in the chemistry of the atmospheric environment and air quality. Ammonia emissions are a major environmental concern, yet they remain poorly quantified. There is a need for a sensitive ammonia instrument to monitor emissions and evaluate their eff...

  3. A SENSITIVE AND AFFORDABLE COMPACT AMMONIA MONITOR - PHASE II

    EPA Science Inventory

    Ammonia has an important role in the chemistry of the atmospheric environment and air quality. Ammonia emissions are a major environmental concern, yet they remain poorly quantified. There is a need for a sensitive ammonia instrument to monitor emissions and evaluate their e...

  4. Removal of ammonia from tarry water using a tubular furnace

    SciTech Connect

    V.V. Grabko; V.A. Kofanova; V.M. Li; M.A. Solov'ev [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

    2009-07-15

    An ammonia-processing system without the use of live steam from OAO Alchevskkoks plant's supply network is considered. Steam obtained from the wastewater that leaves the ammonia column is used to process the excess tarry water, with the release of volatile ammonia.

  5. A Simple Soil Percolation Test Device for Field Environmentalists

    ERIC Educational Resources Information Center

    Smith, William H.; Stark, Phillip E.

    1977-01-01

    A primary responsibility of field environmental health workers is evaluation of individual sewage disposal system sites. The authors of this article developed a practical, accurate, and inexpensive measurement device for obtaining reliable percolation test results. Directions for the construction and use of the device are detailed. Drawings…

  6. Polymer Collapse, Protein Folding, and the Percolation Threshold

    E-print Network

    Meirovitch, Hagai

    Polymer Collapse, Protein Folding, and the Percolation Threshold HAGAI MEIROVITCH University (Macromolecules 1989, 22, 3986­3997) to study protein folding, where H and P are the hydrophobic and polar amino; computer simulation; collapse transition; protein folding Introduction The behavior of dilute polymer

  7. A shape theorem for Riemannian first-passage percolation

    NASA Astrophysics Data System (ADS)

    LaGatta, T.; Wehr, J.

    2010-05-01

    Riemannian first-passage percolation is a continuum model, with a distance function arising from a random Riemannian metric in Rd. Our main result is a shape theorem for this model, which says that large balls under this metric converge to a deterministic shape under rescaling. As a consequence, we show that smooth random Riemannian metrics are geodesically complete with probability of 1.

  8. Dynamical instability in Boolean networks as a percolation problem.

    PubMed

    Squires, Shane; Ott, Edward; Girvan, Michelle

    2012-08-24

    Boolean networks, widely used to model gene regulation, exhibit a phase transition between regimes in which small perturbations either die out or grow exponentially. We show and numerically verify that this phase transition in the dynamics can be mapped onto a static percolation problem which predicts the long-time average Hamming distance between perturbed and unperturbed orbits. PMID:23002759

  9. Dynamical Instability in Boolean Networks as a Percolation Problem

    NASA Astrophysics Data System (ADS)

    Squires, Shane; Ott, Edward; Girvan, Michelle

    2012-08-01

    Boolean networks, widely used to model gene regulation, exhibit a phase transition between regimes in which small perturbations either die out or grow exponentially. We show and numerically verify that this phase transition in the dynamics can be mapped onto a static percolation problem which predicts the long-time average Hamming distance between perturbed and unperturbed orbits.

  10. Percolation Approach to Study Connectivity in Living Neural Networks

    E-print Network

    Tlusty, Tsvi

    by the critical exponent 0.65. We use a theoretic approach based on bond­percolation on a graph to describe have experienced in the last decade [6, 7]. Graph theory has permitted to reduce the com- plexity of a rich variety of natural and artificial networks (e.g. Internet, e­mail, social, collaborations

  11. Bond percolation on a class of clustered random networks

    NASA Astrophysics Data System (ADS)

    Gleeson, James P.

    2009-09-01

    Analytical results are derived for the bond percolation threshold and the size of the giant connected component in a class of random networks with nonzero clustering. The network’s degree distribution and clustering spectrum may be prescribed and theoretical results match well with numerical simulations on both synthetic and real-world networks.

  12. Conformal Field Theory Properties of Two-Dimensional Percolation

    E-print Network

    Flohr, Michael

    Conformal Field Theory Properties of Two-Dimensional Percolation Michael Flohr and Annekathrin M in two dimensions has interesting features in conformal field theory such as the conformal invari- ance Network HPRN-CT-2002-00325 (EUCLID) anne@th.physik.uni-bonn.de 1 #12;conformal field theory which matches

  13. Percolation Approach to Quark-Gluon Plasma and J\\/? Suppression

    Microsoft Academic Search

    N. Armesto; M. A. Braun; E. G. Ferreiro; C. Pajares

    1996-01-01

    It is shown that the critical threshold for percolation of the overlapping\\u000astrings exchanged in heavy ion collisions can naturally explain the sharp\\u000astrong suppresion of $J\\/\\\\psi$ shown by the experimental data on central Pb--Pb\\u000acollisions, which does not occur in central O--U and S--U collisions.

  14. Cluster decomposition of percolation probability on the hexagonal lattice

    E-print Network

    E. S. Antonova; Yu. P. Virchenko

    2009-09-29

    The upper estimate of the percolation threshold of the Bernoulli random field on the hexagonal lattice is found. It is done on the basis of the cluster decomposition. Each term of the decomposition is estimated using the number estimate of cycles on the hexagonal lattice which represent external borders of possible finite clusters containing the fixed lattice vertex.

  15. A Secure Message Percolation Scheme for Wireless Sensor Network

    Microsoft Academic Search

    Choong Seon Hong

    2007-01-01

    Wireless Sensor Network (WSN) deployed in hostile environments suffers from severe security threats. In this paper, we propose a Secure Message Percolation (SMP) scheme for WSN. We engineer a secure group management scheme for dealing with data gathered by groups of co-located sensors and analyze the robustness against increasing number of compromised sensor nodes. Key pre-distribution is performed with the

  16. PERCOLATION AND SUPERCONDUCTIVITY IN ION-IMPLANTED ALUMINIUM FILMS (*)

    E-print Network

    Boyer, Edmond

    L-435 PERCOLATION AND SUPERCONDUCTIVITY IN ION-IMPLANTED ALUMINIUM FILMS (*) F. MEUNIER and P of Si and Ge in Al thin films at 8 K produces alloys exhibiting enhanced superconducting transition in the superconducting transition temperature Tc of several such alloys [2], [5], [6] : Josephson tunnelling

  17. Predicting Oil Recovery using Percolation Theory , SV Buldyrev2

    E-print Network

    Dokholyan, Nikolay V.

    the geological model and flow physics such that quasi-analytical predictions of uncertainty can be made extremely is like passive tracer transport. In other words we have single phase flow from injector to producer (we1 Predicting Oil Recovery using Percolation Theory PR King1 , SV Buldyrev2 , NV Dokholyan2

  18. An equal-time correlation function for directed percolation

    NASA Astrophysics Data System (ADS)

    Beljakov, I.; Hinrichsen, H.

    2010-10-01

    We suggest an equal-time n-point correlation function for systems in the directed percolation universality class which is well defined for all phases and independent of initial conditions. It is defined as the probability that all points are connected with a common ancestor, in the past, by directed paths.

  19. The Use of Percolating Filters in Teaching Ecology.

    ERIC Educational Resources Information Center

    Gray, N. F.

    1982-01-01

    Using percolating filters (components of sewage treatment process) reduces problems of organization, avoids damage to habitats, and provides a local study site for field work or rapid collection of biological material throughout the year. Component organisms are easily identified and the habitat can be studied as a simple or complex system.…

  20. Triangle percolation in mean field random graphs -- with PDE

    E-print Network

    Balázs Ráth; Bálint Tóth

    2008-03-03

    We apply a PDE-based method to deduce the critical time and the size of the giant component of the ``triangle percolation'' on the Erd\\H{o}s-R\\'enyi random graph process investigated by Palla, Der\\'enyi and Vicsek

  1. Percolation in Transparent and Conducting Carbon Nanotube Networks

    E-print Network

    Gruner, George

    Percolation in Transparent and Conducting Carbon Nanotube Networks L. Hu, D. S. Hecht, G. Grüner. Transmission measurements also indicate the usefulness of nanotube network films as a transparent, conductive and chemical sensors9 , field emission devices10,11 , and transparent conductive coatings7 . We12 , and another

  2. Percolative theories of strongly disordered ceramic high-temperature superconductors

    PubMed Central

    Phillips, J. C.

    2010-01-01

    Optimally doped ceramic superconductors (cuprates, pnictides, etc.) exhibit transition temperatures T c much larger than strongly coupled metallic superconductors like Pb (T c = 7.2 K, E g/kT c = 4.5) and exhibit many universal features that appear to contradict the Bardeen, Cooper, and Schrieffer theory of superconductivity based on attractive electron-phonon pairing interactions. These complex materials are strongly disordered and contain several competing nanophases that cannot be described effectively by parameterized Hamiltonian models, yet their phase diagrams also exhibit many universal features in both the normal and superconductive states. Here we review the rapidly growing body of experimental results that suggest that these anomalously universal features are the result of marginal stabilities of the ceramic electronic and lattice structures. These dual marginal stabilities favor both electronic percolation of a dopant network and rigidity percolation of the deformed lattice network. This “double percolation” model has previously explained many features of the normal-state transport properties of these materials and is the only theory that has successfully predicted strict lowest upper bounds for T c in the cuprate and pnictide families. Here it is extended to include Coulomb correlations and percolative band narrowing, as well as an angular energy gap equation, which rationalizes angularly averaged gap/T c ratios, and shows that these are similar to those of conventional strongly coupled superconductors. PMID:20080578

  3. Percolation induced heat transfer in deep unsaturated zones

    USGS Publications Warehouse

    Lu, N.; LeCain, G.D.

    2003-01-01

    Subsurface temperature data from a borehole located in a desert wash were measured and used to delineate the conductive and advective heat transfer regimes, and to estimate the percolation quantity associated with the 1997-1998 El Ni??no precipitation. In an arid environment, conductive heat transfer dominates the variation of shallow subsurface temperature most of the time, except during sporadic precipitation periods. The subsurface time-varying temperature due to conductive heat transfer is highly correlated with the surface atmospheric temperature variation, whereas temperature variation due to advective heat transfer is strongly correlated with precipitation events. The advective heat transfer associated with precipitation and infiltration is the focus of this paper. Disruptions of the subsurface conductive temperature regime, associated with the 1997-1998 El Ni??no precipitation, were detected and used to quantify the percolation quantity. Modeling synthesis using a one-dimensional coupled heat and unsaturated flow model indicated that a percolation per unit area of 0.7 to 1.3 m height of water in two weeks during February 1998 was responsible for the observed temperature deviations down to a depth of 35.2 m. The reported study demonstrated quantitatively, for the first time, that the near surface temperature variation due to advective heat transfer can be significant at a depth greater than 10 m in unsaturated soils and can be used to infer the percolation amount in thick unsaturated soils.

  4. Given enough choice, simple local rules percolate discontinuously

    NASA Astrophysics Data System (ADS)

    Waagen, Alex; D'Souza, Raissa M.

    2014-12-01

    There is still much to discover about the mechanisms and nature of discontinuous percolation transitions. Much of the past work considers graph evolution algorithms known as Achlioptas processes in which a single edge is added to the graph from a set of k randomly chosen candidate edges at each timestep until a giant component emerges. Several Achlioptas processes seem to yield a discontinuous percolation transition, but it was proven by Riordan and Warnke that the transition must be continuous in the thermodynamic limit. However, they also proved that if the number k(n) of candidate edges increases with the number of nodes, then the percolation transition may be discontinuous. Here we attempt to find the simplest such process which yields a discontinuous transition in the thermodynamic limit. We introduce a process which considers only the degree of candidate edges and not component size. We calculate the critical point tc = (1 - ?(1/k))n and rigorously show that the critical window is of size O(n/k(n)) . If k(n) grows very slowly, for example k(n) = log n, the critical window is barely sublinear and hence the phasetransition is discontinuous but appears continuous in finite systems. We also present arguments that Achlioptas processes with bounded size rules will always have continuous percolation transitions even with infinite choice.

  5. Inverse cascade in percolation model: hierarchical description of ...

    E-print Network

    2004-11-01

    Nov 1, 2004 ... the “crack-fusion” model for repetitive cycles of large earthquakes [22, 23, 15, 24]. Their ... dating the influence of mainshocks and aftershocks, juvenile crack ... Noteworthy, we are interested not in a final solution of a percolation ... 3 we derive the average mass of clusters of a given rank using the Tokunaga.

  6. Planar percolation with a glimpse of Schramm-Loewner Evolution

    E-print Network

    to the books of Grimmett [13] and Kesten [18]. We will be interested in the connectivity properties): Theorem 1.1 (Kesten, Schramm, Lawler, Werner, Smirnov). For the (face) percolation on the hexagonal, and to derive Kesten scaling relations. This last fact, which is the last step towards Theorem 1.1, w

  7. The incipient infinite cluster for high-dimensional unoriented percolation

    E-print Network

    Hofstad, Remco van der

    by work of Hara Hara00 [12]. The limiting object is the high-dimensional analogue of Kesten's incipient literature, including the study of random walk on critical percolation clusters, Kesten Kest86a [22] proposed point, the existence of the limit is not obvious. Kesten showed that in d = 2 the conditional

  8. Version of Sept. 1997 GroupInvariant Percolation on Graphs

    E-print Network

    Peres, Yuval

    in it. A well­known example is Kesten's (1959a, b) theorem that a countable group G is amenable iff some­invariant percolation of Kesten's spectral radius theorem. Theorem 1.1. (Existence of Threshold) Let X = X in Theorem 5.1. A quantitative form of Kesten's equivalence was provided by Cheeger (1970) in the continuous

  9. National Center for Electronics Recycling

    NSDL National Science Digital Library

    Used cellphones and laptops can't go in the recycling with the empty soda cans and cereal boxes. So where do they go to be recycled once consumers find new ones? The National Center for Electronics Recycling (NCER) is working on that very problem. Visitors can click on the "Ecycling Basics" tab on the left side of the page to be taken to links to three websites that allow you to search by zip code or an interactive map of the U.S. In the "Resources" tab on the left side of the page, there are many links to resources that include Advocacy Group Reports, Electronics Disposal Studies, Environmentally Sound Management Guidelines, and International documents. Visitors interested in keeping up with the news from NCER, can sign up for their newsletter in the Google groups box, which is located below the menu on the left side of the page.

  10. AMBIENT AMMONIA AND AMMONIUM AEROSOL ACROSS A REGION OF VARIABLE AMMONIA EMISSION DENSITY

    EPA Science Inventory

    The paper presents one year of ambient ammonia (NH3), ammonium (NH4+), hydrochloric acid (HCI), chloride (CI¯), nitric acid (HNO3), nitrate (NO3¯), nitrous acid (HONO), sulfur dioxide (SO2), and sulfate (SO4...

  11. Economic and ecological costs and benefits of streamflow augmentation using recycled water in a California coastal stream.

    PubMed

    Halaburka, Brian J; Lawrence, Justin E; Bischel, Heather N; Hsiao, Janet; Plumlee, Megan H; Resh, Vincent H; Luthy, Richard G

    2013-10-01

    Streamflow augmentation has the potential to become an important application of recycled water in water scarce areas. We assessed the economic and ecological merits of a recycled water project that opted for an inland release of tertiary-treated recycled water in a small stream and wetland compared to an ocean outfall discharge. Costs for the status-quo scenario of discharging secondary-treated effluent to the ocean were compared to those of the implemented scenario of inland streamflow augmentation using recycled water. The benefits of the inland-discharge scenario were greater than the increase in associated costs by US$1.8M, with recreational value and scenic amenity generating the greatest value. We also compared physical habitat quality, water quality, and benthic macroinvertebrate community upstream and downstream of the recycled water discharge to estimate the effect of streamflow augmentation on the ecosystem. The physical-habitat quality was higher downstream of the discharge, although streamflow came in unnatural diurnal pulses. Water quality remained relatively unchanged with respect to dissolved oxygen, pH, and ammonia-nitrogen, although temperatures were elevated. Benthic macroinvertebrates were present in higher abundances, although the diversity was relatively low. A federally listed species, the California red-legged frog (Rana draytonii), was present. Our results may support decision-making for wastewater treatment alternatives and recycled water applications in Mediterranean climates. PMID:23688175

  12. AMMONIA EMISSION FACTORS FROM SWINE FINISHING OPERATIONS

    EPA Science Inventory

    The paper presents results from two new studies at swine finishing facilities. (NOTE: Concentrated animal feeding operations (CAFOs) are being examined in several regions of the U,.S. as major sources of ammonia and particulate matter precursors. EPA's National Risk Management Re...

  13. AMMONIA EMISSION FACTORS FROM SWINE FINISHING OPERATIONS

    EPA Science Inventory

    The paper presents results from two new studies at swine finishing facilities. (NOTE: Concentrated anaimal feeding operations (CAFOs) are being examined in several regions of the U.S. as major sources of ammonia and particulate matter precursors. EPA's National Risk Management Re...

  14. Biodegradable plastic reduces ammonia emission during composting

    Microsoft Academic Search

    K Nakasaki; A Ohtaki; H Takano

    2000-01-01

    Ammonia is the greatest nuisance odor compound among the exhaust gases that evolve during the composting process, in which raw materials with high concentrations of nitrogen, such as wastewater sludge, are decomposed. In the present study, a reduction of NH3 emission during composting of wastewater sludge was tried by mixing biodegradable plastic into composting raw material. Biodegradable plastic acts as

  15. Laser-Based Pulsed Photoacoustic Ammonia Detection

    NASA Astrophysics Data System (ADS)

    Vallespi, Arturo; Slezak, Verónica; Peuriot, Alejandro; Santiago, Guillermo

    2013-09-01

    Detecting ammonia traces is relevant in health, manufacturing, and security areas, among others. As ammonia presents a strong absorption band (the mode) around 10 m, some of the physical properties which may influence its detection by means of pulsed photoacoustic (PA) spectroscopy with a TEA laser have been studied. The characteristics of the ammonia molecule and the laser intensity may result in a nonlinear dependence of the PA signal amplitude on the laser fluence. Ammonia absorption can be described as a simple two-level system with power broadening. As is a polar molecule, it strongly undergoes adsorption phenomena in contact with different surfaces. Therefore, physical adsorption-desorption at the cell’s wall is studied. A theoretical model, based on Langmuir’s assumptions, fits well to the experimental results with stainless steel. Related to these studies, measurements led to the conclusion that, at the used fluenced values, dissociation by multiphotonic absorption at the 10P(32) laser line may be discarded. A calibration of the system was performed, and a detection limit around 190 ppb (at 224 ) was achieved.

  16. Ammonia release method for depositing metal oxides

    DOEpatents

    Silver, G.L.; Martin, F.S.

    1994-12-13

    A method is described for depositing metal oxides on substrates which is indifferent to the electrochemical properties of the substrates and which comprises forming ammine complexes containing metal ions and thereafter effecting removal of ammonia from the ammine complexes so as to permit slow precipitation and deposition of metal oxide on the substrates. 1 figure.

  17. Ammonia release method for depositing metal oxides

    DOEpatents

    Silver, Gary L. (Centerville, OH); Martin, Frank S. (Farmersville, OH)

    1994-12-13

    A method of depositing metal oxides on substrates which is indifferent to the electrochemical properties of the substrates and which comprises forming ammine complexes containing metal ions and thereafter effecting removal of ammonia from the ammine complexes so as to permit slow precipitation and deposition of metal oxide on the substrates.

  18. Broiler cake potential to emit ammonia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spatial differences for ammonia (NH3) flux from litter are evident within broiler houses especially when considering friable litter and caked surfaces. The objectives of this study were to quantify NH3 generation potential between different sources of cake (two separate farms having variable length...

  19. HOW MUCH AMMONIA DO DAIRY FARMS EMIT?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dairy farms, along with other animal feeding operations, are being asked to consider a consent agreement with the U.S. Environmental Protection Agency (EPA) to fund research into whether or not air pollution laws apply to farms. The major concern is ammonia emission with a maximum limit of 100 pound...

  20. AMMONIA REMOVAL FROM MAMMALIAN CELL CULTURE MEDIUM

    EPA Science Inventory

    Metabolites such as ammonia and lactic formed during mammalian cell culture can frequently be toxic to the cells themselves beyond a threshold concentration of the metabolites. ell culture conducted in the presence of such accumulated metabolites is therefore limited in productiv...

  1. Reflection-based sensor for gaseous ammonia

    Microsoft Academic Search

    Ákos Markovics; Géza Nagy; Barna Kovács

    2009-01-01

    In this work we describe the fabrication of an ammonia sensor on anodized aluminum substrate. Pure aluminum was oxidized with direct current (DC) method at different voltages to obtain oxide layers with different porosity. The adsorption capacities of the differently prepared layers were measured. Bromophenol blue (BPB), bromocresol green (BCG) and bromocresol purple (BCP) indicators were immobilized by simple adsorption.

  2. Planar optical waveguide sensor of ammonia

    NASA Astrophysics Data System (ADS)

    Sarkisov, Sergey S.; Curley, Michael J.; Boykin, Courtney; Diggs, Darnell E.; Grote, James G.; Hopkins, Frank K.

    2004-12-01

    We describe a novel sensor of ammonia based on a planar optical waveguide made of a thin film of polymer polyimide doped with indicator dye bromocresol purple. The film of dye-doped polyimide demonstrated reversible increase of absorption with a peak near 600 nm in response to presence of ammonia in ambient air. Coupling of input and output optic fibers with the waveguide was done by means of coupling prisms or coupling grooves. The latter configuration has the advantage of low cost, less sensitivity to temperature variation, and the possibility of coupling from both sides of the waveguide. Special experimental setup was built to test the sensor. It included test gas chamber with sealed optic fiber feed-throughs, gas filling line, laser source, photodetector, and signal processing hardware and software. The sensor was capable of detecting 100 ppm of ammonia in air within 8 seconds. Further increase of sensitivity can be achieved by adding more dye dopant to the polymer, increase of the length of the waveguide, and suppression of noise. Overexposure of the sensor to more than 5000 ppm of ammonia led to the saturation of the polymer film and, as a result, significant decrease of sensitivity and increase of the response time. The sensor can be used as low cost component of a distributed optical network of chemical sensors for monitoring presence of hazardous industrial pollutants in air.

  3. Radiation Chemistry in Ammonia-Water Ices

    NASA Technical Reports Server (NTRS)

    Loeffler, M. J.; Raut, U.; Baragiola, R. A.

    2010-01-01

    We studied the effects of 100 keV proton irradiation on films of ammonia-water mixtures between 20 and 120 K. Irradiation destroys ammonia, leading to the formation and trapping of H2, N2 NO, and N2O, the formation of cavities containing radiolytic gases, and ejection of molecules by sputtering. Using infrared spectroscopy, we show that at all temperatures the destruction of ammonia is substantial, but at higher temperatures (120 K), it is nearly complete (approximately 97% destroyed) after a fluence of 10(exp 16) ions per square centimeter. Using mass spectroscopy and microbalance gravimetry, we measure the sputtering yield of our sample and the main components of the sputtered flux. We find that the sputtering yield depends on fluence. At low temperatures, the yield is very low initially and increases quadratically with fluence, while at 120 K the yield is constant and higher initially. The increase in the sputtering yield with fluence is explained by the formation and trapping of the ammonia decay products, N2 and H2 which are seen to be ejected from the ice at all temperatures.

  4. ACUTE TOXICITY OF AMMONIA TO FATHEAD MINNOWS

    EPA Science Inventory

    The acute toxicity of ammonia to fathead minnows Pimephales promelas was measured in 35, 96-hour, flow-through tests. The fish were from both wild and hatchery-reared stocks, and ranged in size from 0.1 to 2.3 g. The 96-hour median lethal concentrations (LC50) ranged from 0.75 to...

  5. 21 CFR 573.180 - Anhydrous ammonia.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...should not be fed to lactating dairy cows producing less than 32...corn plant material for use in dairy or beef cattle rations. ...aqueous ammonia is to be fed to dairy cattle only. (b)...

  6. OPTIMIZED CHEMILUMINESCENCE SYSTEM FOR MEASURING ATMOSPHERIC AMMONIA

    EPA Science Inventory

    The optimization and testing of a continuous measurement system for analyzing atmospheric ammonia concentrations (0 to 10 ppb) is described. The measurement system combines an ultra-sensitive chemiluminescence nitric oxide detector, with a thermal converter for NH3 to nitric oxid...

  7. Subsurface manure application to reduce ammonia emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Incorporation into soil is generally recommended to reduce ammonia volatilization and nutrient runoff following land application of manures. A range of subsurface applicators are available for manure incorporation with minimal soil disturbance in reduced tillage systems, but none have been widely a...

  8. AMMONIA CONCENTRATIONS IN PINK SALMON, ONCORHYNCHUS GORBUSCHA,

    E-print Network

    Agency [EPA] 1974). The EPA method was modified by stabilizing the heat source during the reaction from the gravel is critical for survival ofyoung salmon. The young salmon have a higher rate the end of yolk absorption excrete ammonia at a higher rate than eggs or early alevins (Rice and Stokes

  9. Influence of carbon nanotube dimensions on the percolation characteristics of carbon nanotube/polymer composites

    NASA Astrophysics Data System (ADS)

    Shehzad, Khurram; Ahmad, Mirza Nadeem; Hussain, Tajamal; Mumtaz, Muhammad; Shah, Asma Tufail; Mujahid, Adnan; Wang, Chao; Ellingsen, Josef; Dang, Zhi-Min

    2014-08-01

    The effect of carbon nanotube aspect ratio (AR) on the percolation characteristics of their polymer composites was investigated by melt blending the multi-wall carbon nanotubes (MWCNTs) with different AR with a thermoplastic elastomer. Previously, most studies reported the effect of aspect ratio of MWCNTs only in the context of achieving the maximum electrical conductivity at lower percolation thresholds in the polymer composites. In this study, our results indicate that aspect ratio can also influence other percolation properties such as the pre-percolation conductivity, percolation conductivity and post-percolation conductivity, shape of the percolation curve, and the width of the insulator-conductor transition. We have established that AR can be used to tailor the percolation curves from sharp to quasi-linear ones, which can help us fabricate the percolative composites with stable electrical properties. Experimental results suggested that the mathematically calculated nominal AR of the MWCNTs was an unclear parameter to correlate with the percolation characteristics of the composites. Instead, an approach taking into consideration the nominal length (l) and the diameter (d) of the MWCNTs individually rather than as a combined AR (l/d) parameter gave a better explanation of the relation between MWCNT dimensions and percolation characteristics.

  10. Recycling and surplus chemical programs

    SciTech Connect

    Harper, T.J.

    1993-05-01

    In 1988, 45 years of defense production came to a close at the US Department of Energy (DOE) Hanford Site. The mission of the Hanford Site was formally changed to environmental restoration and remediation. Westinghouse Hanford Company (WHC) is the management and operations (M&O) contractor leading the cleanup. Within the framework of future Site cleanup, Hanford recycling and surplus chemical programs are making a viable contribution today to waste minimization, diversion of materials from the waste stream, and setting a standard for future operations. This paper focuses on two successful efforts: paper recycling and surplus chemical sales.

  11. Polymer recycling: opportunities and limitations.

    PubMed Central

    Stein, R S

    1992-01-01

    The disposal of polymer solid waste by means other than landfilling is necessary. The various approaches-source reduction, incineration, degradation, composting, and recycling-all have their roles and must be employed in an integrated manner. Where appropriate, recycling has ecological advantages, but its application is dependent upon the feasibility of collection, sorting, and/or compatibilization of resulting mixtures to produce economically viable products. The practice should be encouraged by societal or legislative pressure which recognizes that the cost of disposal should be a factor in determining the cost of a product. PMID:11607263

  12. The Recycling Solution: How I Increased Recycling on Dilworth Road

    ERIC Educational Resources Information Center

    Keller, J. Jacob

    2010-01-01

    The grandson of Fred Keller, one of the founders of behavior analysis, Jacob was 10 years old when he conducted the project for his elementary school science fair. We recently contacted Jacob to learn more about his project. He told us the inspiration came from a class field trip to the county recycling center, which included seeing video footage…

  13. Ammonia and ammonium hydroxide sensors for ammonia/water absorption machines: Literature review and data compilation

    SciTech Connect

    Anheier, N.C. Jr.; McDonald, C.E.; Cuta, J.M.; Cuta, F.M.; Olsen, K.B.

    1995-05-01

    This report describes an evaluation of various sensing techniques for determining the ammonia concentration in the working fluid of ammonia/water absorption cycle systems. The purpose of this work was to determine if any existing sensor technology or instrumentation could provide an accurate, reliable, and cost-effective continuous measure of ammonia concentration in water. The resulting information will be used for design optimization and cycle control in an ammonia-absorption heat pump. PNL researchers evaluated each sensing technology against a set of general requirements characterizing the potential operating conditions within the absorption cycle. The criteria included the physical constraints for in situ operation, sensor characteristics, and sensor application. PNL performed an extensive literature search, which uncovered several promising sensing technologies that might be applicable to this problem. Sixty-two references were investigated, and 33 commercial vendors were identified as having ammonia sensors. The technologies for ammonia sensing are acoustic wave, refractive index, electrode, thermal, ion-selective field-effect transistor (ISFET), electrical conductivity, pH/colormetric, and optical absorption. Based on information acquired in the literature search, PNL recommends that follow-on activities focus on ISFET devices and a fiber optic evanescent sensor with a colormetric indicator. The ISFET and fiber optic evanescent sensor are inherently microminiature and capable of in situ measurements. Further, both techniques have been demonstrated selective to the ammonium ion (NH{sub 4}{sup +}). The primary issue remaining is how to make the sensors sufficiently corrosion-resistant to be useful in practice.

  14. Ammonia scrubbing makes high sulfur fuels economical

    SciTech Connect

    Brown, G.N.

    1998-07-01

    The first commercial in situ forced oxidation ammonia scrubber system developed by marsulex Environmental Technologies (MET), formerly GE Environmental Systems (GEESI), was completed at the Dakota Gasification Company's Great Plains Synfuels Plant near Beulah, North Dakota, USA. The patented MET ammonia scrubbing system simultaneously removes acid gases while producing a high value byproduct, ammonium sulfate. The MET process was developed to eliminate performance issues associated with first generation ammonia scrubbing systems by unique application of standard, proven FGD equipment. The MET ammonia scrubbing process is particularly attractive for application on units which can reduce power generating costs by firing high sulfur content fuels. In contrast to the ever increasing cost of lower sulfur fuels, the increasing levels of sulfur in the fuel can represent a greater economic benefit to the utility by burning a lower cost fuel, coupled with production of a high value byproduct. The sale of the byproduct, ammonium sulfate, offsets most of the scrubber capital and operating costs and, in some cases, can generate revenue for the utility. This, in combination with the increasing need to replenish depleted sulfur from soil, makes production of ammonium sulfate an ideal product for sale in the agricultural market. In this paper, the 300 MW commercial ammonium sulfate process installed in North Dakota is described. The results of initial operation and testing are discussed. Current photos that illustrate the unique equipment and materials selection are presented. The ammonia scrubbing process economics for application using various sulfur fuels are compared. An economic comparison, in $/mmBTU, which incorporates reduced high sulfur fuel cost and the life cycle economics of the air pollution control system is also presented.

  15. AMMONIA CONCENTRATION IN SALTSTONE HEADSPACE SUMMARY REPORT

    SciTech Connect

    Zamecnik, J; Alex Cozzi, A

    2008-09-26

    The Saltstone Facility Documented Safety Analysis (DSA) is under revision to accommodate changes in the Composite Lower Flammability Limit (CLFL) from the introduction of Isopar into Tank 50. Saltstone samples were prepared with an 'MCU' type salt solution spiked with ammonia. The ammonia released from the saltstone was captured and analyzed. The ammonia concentration found in the headspace of samples maintained at 95 C and 1 atm was, to 95% confidence, less than or equal to 3.9 mg/L. Tank 50 is fed by several influent streams. The salt solution from Tank 50 is pumped to the salt feed tank (SFT) in the Saltstone Production Facility (SPF). The premix materials cement, slag and fly ash are blended together prior to transfer to the grout mixer. The premix is fed to the grout mixer in the SPF and the salt solution is incorporated into the premix in the grout mixer, yielding saltstone slurry. The saltstone slurry drops into a hopper and then is pumped to the vault. The Saltstone Facility Documented Safety Analysis (DSA) is under revision to accommodate changes in the Composite Lower Flammability Limit (CLFL) from the introduction of Isopar{reg_sign} L into Tank 50. Waste Solidification-Engineering requested that the Savannah River National Laboratory (SRNL) perform testing to characterize the release of ammonia in curing saltstone at 95 C. The test temperature represents the maximum allowable temperature in the Saltstone Disposal Facility (SDF). Ammonia may be present in the salt solution and premix materials, or may be produced by chemical reactions when the premix and salt solution are combined. A final report (SRNS-STI-2008-00120, Rev. 0) will be issued that will cover in more depth the information presented in this report.

  16. 40 CFR 261.6 - Requirements for recyclable materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...6(d).) (2) Owners or operators of facilities that recycle recyclable materials without storing them before they are recycled...permitting requirements with hazardous waste management units that recycle hazardous wastes are subject to the requirements of...

  17. 40 CFR 261.6 - Requirements for recyclable materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...6(d).) (2) Owners or operators of facilities that recycle recyclable materials without storing them before they are recycled...permitting requirements with hazardous waste management units that recycle hazardous wastes are subject to the requirements of...

  18. 40 CFR 261.6 - Requirements for recyclable materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...6(d).) (2) Owners or operators of facilities that recycle recyclable materials without storing them before they are recycled...permitting requirements with hazardous waste management units that recycle hazardous wastes are subject to the requirements of...

  19. 40 CFR 261.6 - Requirements for recyclable materials.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...6(d).) (2) Owners or operators of facilities that recycle recyclable materials without storing them before they are recycled...permitting requirements with hazardous waste management units that recycle hazardous wastes are subject to the requirements of...

  20. Automobile Recycling Policy: Findings and Recommendations

    E-print Network

    Field, Frank

    This report focuses on recycling. As an objective neutral party, MIT has compiled a knowledge base that examines the many complex issues relating to re-cycling. Although this report was prepared at the request of the ...

  1. 76 FR 71861 - America Recycles Day, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-18

    ...and expand existing recycling programs and dedicate...million tons of used electronics annually, and without following proper recycling and management practices, the disposal of our old computers, monitors...developing new, sustainable electronics technologies, my...

  2. Residential Refrigerator Recycling Ninth Year Retention Study

    E-print Network

    Residential Refrigerator Recycling Ninth Year Retention Study Study ID Nos. 546B, 563 Prepared RECYCLING PROGRAMS Study ID Nos. 546B and 563 Prepared for Southern California Edison Rosemead, California

  3. Compositional evaluation of asphalt binder recycling agents

    E-print Network

    Madrid, Richard Charles

    1997-01-01

    new asphalt binder. The high temperature Superpave TM Performance Grade (PG) specifications for recycled asphalt binders were found to be highly dependent on the aged asphalt. In addition, as the amount of saturates in the aromatic recycling agent...

  4. Recycling of used perfluorosulfonic acid membranes

    DOEpatents

    Grot, Stephen (Middletown, DE); Grot, Walther (Chadds Ford, PA)

    2007-08-14

    A method for recovering and recycling catalyst coated fuel cell membranes includes dissolving the used membranes in water and solvent, heating the dissolved membranes under pressure and separating the components. Active membranes are produced from the recycled materials.

  5. Converting Garbage to Gold: Recycling Our Materials.

    ERIC Educational Resources Information Center

    Chandler, William U.

    1984-01-01

    Recycling conserves energy, fights pollution and inflation, creates jobs, and improves the outlook for the future of materials. But converting a throwaway society to recycling will depend on finding good markets for waste paper and scrap metals. (RM)

  6. Application of groundwater thresholds for trace elements on percolation water: a case study on percolation water from Northern German lowlands.

    PubMed

    Godbersen, L; Duijnisveld, W H M; Utermann, J; Gäbler, H-E; Kuhnt, G; Böttcher, J

    2012-01-01

    The German insignificance thresholds (GFS) for groundwater, derived with an added risk approach, will soon be adopted as trigger values for percolation water entering groundwater. The physicochemical properties of the vadose zone differ considerably from those of groundwater, which may lead to difficulties in the applicability of groundwater-derived GFS to percolation water. To test the applicability of the GFS to percolation water regarding the concentration level and the field-scale variability, 46 sites in Northern Germany were sampled, including arable land, grassland, and forest, situated on three spatially dominant parent materials: sand, glacial loam, and loess. Concentrations of As, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, Sb, Sn, V, Zn, and F were analyzed in percolation water from the transition between the unsaturated to the saturated zone. We compared median and 90th percentile values of the background concentrations with the GFS. In more than 10% of all samples, background concentrations of Cd, Co, Ni, V, or Zn exceeded the GFS. We evaluated the applicability of the GFS on field-scale medians of background concentrations taking field-scale interquartile distance and the bootstrap percentile confidence interval of the field scale median of trace element background concentrations into consideration. Statements about exceedance or nonexceedance of GFS values could only be made with acceptable statistical uncertainty (? ? 0.1) when operational median concentrations were about one third higher or lower than the corresponding GFS. PMID:22751069

  7. Waste Management and Recycling in Lab Batteries can be recycled in the VWR stockroom

    E-print Network

    Cohen, Robert E.

    Waste Management and Recycling in Lab · Batteries can be recycled in the VWR stockroom · Electronic odors and collect the first rinse with its associated hazardous waste stream), remove or deface recycle it! · MIT recycled 2773 tons of waste in 2010 · Remember b onl hat o need!· Remember buy only what

  8. Where can I recycle it year-round? Item Local Recycling Locations

    E-print Network

    Escher, Christine

    Where can I recycle it year-round? Item Local Recycling Locations Styrofoam First Alternative Co-op Recycling Center, 1007 SE 3rd St., 541-753-3115 (small fee) Packing Peanuts OSU Surplus, 644 SW 13 th St., 541-737-7347 Commercial shipping stores Film Plastics First Alternative Co-op Recycling Center, 1007

  9. Research Report Recycling gone bad: When the option to recycle increases

    E-print Network

    Loudon, Catherine

    Research Report Recycling gone bad: When the option to recycle increases resource consumption Jesse Abstract In this study, we propose that the ability to recycle may lead to increased resource usage compared to when a recycling option is not available. Supporting this hypothesis, our first experiment

  10. Recycling at Penn State's Beaver Stadium. "Recycle on the Go" Success Story

    ERIC Educational Resources Information Center

    US Environmental Protection Agency, 2009

    2009-01-01

    With a 13-year-old recycling program, The Pennsylvania State University's (Penn State) Beaver Stadium in the past diverted nearly 30 tons of recyclables per year from local landfills. A new initiative to promote recycling in the stadium's tailgating area has helped Penn State more than triple its old recycling record, collecting 112 tons in 2008.…

  11. What Makes a Recycler?A Comparison of Recyclers and Nonrecyclers

    Microsoft Academic Search

    Joanne Vining; Angela Ebreo

    1990-01-01

    Knowledge and motivational factors represent important but neglected topics in the study of recycling behavior. This article examines differences in knowledge, motives, and demographic characteristics of people who have the opportunity to recycle voluntarily. Information on these variables was obtained for 197 households in Illinois. The results indicated that recyclers in general were more aware of publicity about recycling and

  12. Research & development on recycling technology of photovoltaic power generation systems - social system for PV recycling

    Microsoft Academic Search

    N. Urashima; M. Izumina; A. Arita; K. Matsumoto

    2003-01-01

    The research and development on recycling and re-use technologies for PV systems have been conducted as a NEDO project since 2001 in order to achieve low recycling cost and high recycling rates. As a result of analysis on recycling rates and cost estimation by the experiments for the existing technologies, the starting point of this R&D project is identified quantitatively.

  13. Identiflcation of delay dominant recycle systems

    Microsoft Academic Search

    R. B. Gopaluni; H. Raghavanz; R. S. Patwardhanx; S. L. Shah; G. A. Dumont

    A new identiflcation method for single-input-single-output delay dominant recycle systems is presented in this paper. Identiflcation of recycle systems is similar to that of closed loop systems. However, identiflcation of recycle systems poses certain challenges in that the input-equivalent signal in the closed loop identiflcation is not available for recycle systems. Therefore, special identiflcation routines are required to ensure consistency

  14. Proceedings of the waste recycling workshop

    SciTech Connect

    Bailey, R.E.; Thomas, A.F.; Ries, M.A. [eds.] [Ohio State Univ., Columbus, OH (United States)] [eds.; Ohio State Univ., Columbus, OH (United States)

    1993-12-31

    Recorded are seventeen talks from five sessions at the workshop. FERMCO`s recycling program, state of the art recycling technology, and an integrated demonstration of deactivation, decommissioning and decommissioning are presented in the plenary session. In the concrete session, decontamination and recycling are discussed. In the transite session, regulations are considered along with recycling and decontamination. In the metals session, radioactive scrap metals are emphasized. And in the regulatory considerations and liabilities session, DOE and EPA viewpoints are discussed. (GHH)

  15. Establishing relative sensitivities of various toxicity testing organisms to ammonia

    SciTech Connect

    Karle, L.M.; Mayhew, H.L.; Barrows, M.E.; Karls, R.K. [Battelle/Marine Sciences Lab., Sequim, WA (United States)

    1994-12-31

    The toxicity of ammonia to various organisms was examined to develop a baseline for mortality in several commonly used testing species. This baseline data will assist in choosing the proper test species and in interpreting results as they pertain to ammonia. Responses for two juvenile fish species, three marine amphipods, and two species of mysid shrimp were compared for their sensitivity to levels of ammonia. All mortality caused by ammonia in the bottom-dwelling Citharichthys stigmaeus occurred within 24 h of exposure, whereas mortality in the silverside, Menidia beryllina, occurred over the entire 96-h test duration. Responses to ammonia varied among the amphipods Rhepoxynius abronius, Ampelisca abdita, and Eohaustorius estuarius. R. abronius and A. abdita showed similar sensitivity to ammonia at lower concentrations; A. abdita appeared more sensitive than R. abronius at levels above 40 mg/L. Concentrations of ammonia required to produce significant mortality in the amphipod E. estuarius were far higher than the other species examined (> 100 mg/L NH{sub 3}). A comparison of ammonia toxicity with two commonly used invertebrates, Holmesimysis sculpts and Mysidopsis bahia, suggest that these two species of mysid have similar sensitivities to ammonia. Further studies with ammonia that examine sensitivity of different organisms should be conducted to assist regulatory and environmental agencies in determining appropriate test species and in interpreting toxicological results as they may be affected by levels of ammonia.

  16. 75 FR 71003 - America Recycles Day, 2010

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-19

    ...environment. On America Recycles Day, we celebrate the individuals...successes on America Recycles Day, we must also recommit to building...valuable resources such as rare earth minerals. To address the problems...environment. On America Recycles Day, let us respond to our...

  17. The College Student's Guide to Recycling,

    E-print Network

    Kidd, William S. F.

    users get a discount on their coffee! 5. Recycle old ink jet cartridges in the bins supplied on campus: batteries, ink jets, toners, cell phones and electronics. What Can I Recycle? All over campus you'll findThe College Student's Guide to Recycling, Reduction, and Reuse UNIVERSITY AT ALBANY Phone

  18. Materials recycling: the virtue of necessity

    Microsoft Academic Search

    1983-01-01

    Recycling materials saves energy and money, protects the environment, and cuts waste disposal costs. Despite these advantages, only about one-quarter of the world's aluminum or steel is recovered for reuse. Areas with high energy costs, scarce raw materials, and a strong desire to protect the environment have performed best in recycling. Iron, aluminum, and wood take priority in recycling because

  19. The Hang-Ups on Recycling

    ERIC Educational Resources Information Center

    Environmental Science and Technology, 1975

    1975-01-01

    While all seem to agree that recycling will alleviate solid waste problems and energy and mineral shortages, recycling is, at present, bogged down by the thin market for recycled materials, the recessionary business picture, the vertical integration of many companies, unfavorable tax laws, and high rail freight rates. (BT)

  20. Ames Lab 101: Rare-Earth Recycling

    ScienceCinema

    Ryan Ott

    2013-06-05

    Recycling keeps paper, plastics, and even jeans out of landfills. Could recycling rare-earth magnets do the same? Perhaps, if the recycling process can be improved. Scientists at the U.S. Department of Energy's Ames Laboratory are working to more effectively remove the neodymium, a rare earth, from the mix of other materials in a magnet.

  1. Ames Lab 101: Rare-Earth Recycling

    SciTech Connect

    Ryan Ott

    2012-09-05

    Recycling keeps paper, plastics, and even jeans out of landfills. Could recycling rare-earth magnets do the same? Perhaps, if the recycling process can be improved. Scientists at the U.S. Department of Energy's Ames Laboratory are working to more effectively remove the neodymium, a rare earth, from the mix of other materials in a magnet.

  2. Textile Recycling, Convenience, and the Older Adult.

    ERIC Educational Resources Information Center

    Domina, Tanya; Koch, Kathryn

    2001-01-01

    Results of a study to examine the recycling practices and needs of older adults (n=217) indicated that older adults do recycle traditional materials, but need accommodations for physical limitations. They report textile recycling as time consuming and difficult and used donations to religious organizations as their principal means of textile…

  3. School Recycling Programs: A Handbook for Educators.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC.

    This brochure describes some of the many recycling program options that schools can implement in their communities. It focuses on implementing actual recycling projects as a way of teaching the importance and benefits of recycling. The text examines the solid waste crisis and why Americans cannot continue to possess a disposable mentality. It…

  4. Really Recycled-SeaWorld Classroom Activity

    NSDL National Science Digital Library

    Sea World - Just for Teachers

    2012-04-03

    In this activity, students will be able to recycle newspaper into their own conservation message. Students will also be given the opportunity to write about their experience with recycling or persuade the reader why it is important to recycle based on what they learned in the activity.

  5. Recycling at Mooov-In 2011

    E-print Network

    Julien, Christine

    Cardboard Recycling at Mooov-In 2011 For the second year in a row, Division of Housing and Food Service (DHFS) and Recycling & Sustainability teamed up to divert as much cardboard as possible from area landfills. In addition to the paper, cardboard, aluminum and plastic recycling available in all residence

  6. Recycling of Eukaryotic Posttermination Ribosomal Complexes

    E-print Network

    Bedwell, David M.

    Recycling of Eukaryotic Posttermination Ribosomal Complexes Andrey V. Pisarev,1 Christopher U- somes in posttermination complexes (post- TCs), which must therefore be recycled by releasing m elongation factor EF-G and a ribosome recycling factor RRF. Eukaryotes do not encode a RRF homo- log

  7. Material Recycling and Waste Disposal Document Control

    E-print Network

    Guillas, Serge

    1 Material Recycling and Waste Disposal Procedure Document Control Document Created by 23, treatment, handling, transport and disposal of recyclable materials and residual wastes so as to maximise the opportunity and value for the recyclable materials and to minimise the quantity of residual materials

  8. WASTE MINIMISATION AND RECYCLING POLICY 1.Introduction

    E-print Network

    Mottram, Nigel

    WASTE MINIMISATION AND RECYCLING POLICY 1.Introduction University of Glasgow has stated its overall as it relates to waste minimisation and recycling. 2.Recycling Policy Statement The University of Glasgow will develop the existing Environmental Policy by minimising the production of waste through good purchasing

  9. NATURAL SURFACTANTS IN PAPER RECYCLING

    EPA Science Inventory

    The objective of this project is to introduce new types of surfactants based on renewable materials (sugar surfactants) for use in ink removal from recycled paper. By applying green chemistry approaches we not only will solve an important industry and environmental problem but...

  10. Recycled Yo-Yo Challenge

    NSDL National Science Digital Library

    National Museum of American History

    2012-06-26

    In this activity, learners are challenged to build their own yo-yo toys using items found in their recycling bins. Learners search for materials to use for each part of the toy: two discs, an axle, and string. Learners then sketch their invention, assemble the parts, and test it out. Learners are encouraged to tweak their yo-yos and make improvements.

  11. New approaches to recycling tires

    Microsoft Academic Search

    1991-01-01

    Steel-belted radial tires are potentially one of the most recyclable products created by modern industry, although the potential has been barely tapped. Discarded tires pile up at an astonishing rate each year - 234 million in the US and 26 million passenger tire equivalents in Canada. They represent a mother lode of raw material waiting for modern day miners to

  12. Chemical recycling of scrap composites

    NASA Technical Reports Server (NTRS)

    Allred, Ronald E.; Salas, Richard M.

    1994-01-01

    There are no well-developed technologies for recycling composite materials other than grinding to produce fillers. New approaches are needed to reclaim these valuable resources. Chemical or tertiary recycling, conversion of polymers into low molecular weight hydrocarbons for reuse as chemicals or fuels, is emerging as the most practical means for obtaining value from waste plastics and composites. Adherent Technologies is exploring a low-temperature catalytic process for recycling plastics and composites. Laboratory results show that all types of plastics, thermosets as well as thermoplastics, can be converted in high yields to valuable hydrocarbon products. This novel catalytic process runs at 200 C, conversion times are rapid, the process is closed and, thus, nonpolluting, and no highly toxic gas or liquid products have been observed so no negative environmental impact will result from its implementation. Tests on reclamation of composite materials show that epoxy, imide, and engineering thermoplastic matrices can be converted to low molecular weight hydrocarbons leaving behind the reinforcing fibers for reuse as composite reinforcements in secondary, lower-performance applications. Chemical recycling is also a means to dispose of sensitive or classified organic materials without incineration and provides a means to eliminate or reduce mixed hazardous wastes containing organic materials.

  13. Estimation of continental precipitation recycling

    Microsoft Academic Search

    Kaye L. Brubaker; Dara Entekhabi; P. S. Eagleson

    1993-01-01

    The total amount of water that precipitates on large continental regions is supplied by two mechanisms: (1) advection from the surrounding areas external to the region and (2) evaporation and transpiration from the land surface within the region. The latter supply mechanism is tantamount to the recycling of precipitation over the Continental area. The degree to which regional precipitation is

  14. Recycled Water Poses Disinfectant Problem

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1973

    1973-01-01

    Discusses the possible health hazards resulting from released nucleic acid of inactivated viruses, chlorinated nonliving organic molecules, and overestimated reliability of waste treatment standards. Suggests the recycle system use a dual disinfectant such as chlorine and ozone in water treatment. (CC)

  15. Household-battery recycling plant

    SciTech Connect

    Weber, A.; Antenen, A. [Batrec Technology A.G., Dietikon (Switzerland)

    1995-12-31

    Batrec operates a plant for the recycling of used dry batteries with a capacity of 3,000 tons per year. The plant is situated in a tourist area of Switzerland and has complied with all the strict emission restrictions. The process yields four products: FeMn, Zn, Hg and slag. No hazardous waste is produced. All types of batteries can be treated.

  16. Materials Recycling: The Virtue of Necessity. Worldwatch Paper 56.

    ERIC Educational Resources Information Center

    Chandler, William U.

    This report focuses on the necessity and advantages of recycling. Following an introduction, the report is divided into five sections, addressing respectively: the necessity of recycling; waste paper recycling; aluminum recycling; iron and steel recycling; and three steps to a "recycling society." These steps include: (1) requiring that consumers…

  17. USF Physical Plant Recycling Program Updated November 2013

    E-print Network

    Meyers, Steven D.

    Recyclables (Bulbs, Tires, etc.) 7 tons #12;Recycle Ratio for FY 2012/2013 · Total waste generated: 3419 tonsUSF Physical Plant Recycling Program Updated November 2013 #12;Beginnings · Program initiated · Continuously expanding recycling efforts #12;Paper Recycling · Currently recycling mixed paper Office paper

  18. Recycling Tubulin We "recycle" tubulin fractions stored at -80C after the PC column and

    E-print Network

    Mitchison, Tim

    Recycling Tubulin We "recycle" tubulin fractions stored at -80¡C after the PC column and store the recycled tubulin in small aliquots for day-to-day use. We generally store recycled tubulin in Injection = 2-4¡C) II. Recycling Protocol 1. Thaw 3-4 3 ml PC column fractions at 37¡C. Transfer to ice and mix

  19. Efficient regeneration of partially spent ammonia borane fuel

    SciTech Connect

    Davis, Benjamin Lee [Los Alamos National Laboratory; Gordon, John C [Los Alamos National Laboratory; Stephens, Frances [Los Alamos National Laboratory; Dixon, David A [UNIV OF ALABAMA; Matus, Myrna H [UNIV OF ALABAMA

    2008-01-01

    A necessary target in realizing a hydrogen (H{sub 2}) economy, especially for the transportation sector, is its storage for controlled delivery, presumably to an energy producing fuel cell. In this vein, the U.S. Department of Energy's (DOE) Centers of Excellence (CoE) in Hydrogen Storage have pursued different methodologies, including metal hydrides, chemical hydrides, and sorbents, for the expressed purpose of supplanting gasoline's current > 300 mile driving range. Chemical hydrogen storage has been dominated by one appealing material, ammonia borane (H{sub 3}B-NH{sub 3}, AB), due to its high gravimetric capacity of hydrogen (19.6 wt %) and low molecular weight (30.7 g mol{sup -1}). In addition, AB has both hydridic and protic moieties, yielding a material from which H2 can be readily released. As such, a number of publications have described H{sub 2} release from amine boranes, yielding various rates depending on the method applied. Even though the viability of any chemical hydrogen storage system is critically dependent on efficient recyclability, reports on the latter subject are sparse, invoke the use of high energy reducing agents, and suffer from low yields. For example, the DOE recently decided to no longer pursue the use of NaBH{sub 4} as a H{sub 2} storage material, in part because of inefficient regeneration. We thus endeavored to find an energy efficient regeneration process for the spent fuel from H{sub 2} depleted AB with a minimum number of steps.

  20. Percolation effects on entangled polymer rheology and the glass transition

    NASA Astrophysics Data System (ADS)

    Wool, Richard P.

    2012-07-01

    Current thinking on the fundamentals of entangled polymer melt rheology suggests that stress relaxation in the terminal zone occurs via Reptation, chain-end fluctuation and (convective) constraint release. This scenario is not correct. It is shown through a series of experiments with selectively deuterated model polymers that relaxation occurs through a percolation process which permits large clusters of entangled polymers to stress relax before their conformations are fully relaxed. The percolation model of entanglements (R.P. Wool, Macromolecules 26, 1564, 1993) makes unique predictions regarding the dynamics of polymer chains in the terminal relaxation zone. These include: (a) Reptating homopolymer chains with molecular weight M >> Mc appear to be non-Reptating as their ends and centers relax at the same rate in a Rouse-like manner during percolation. (b) The mechanical relaxation time ?(M) is related to the Reptation time Tr˜ M3 by ?(M) = Tr[(1-Mc/M)Me/Mc]2, which is the origin of the zero shear viscosity behaving as ?o˜M3.4 (c) The biggest surprise is that during stress relaxation, the random coil dimensions Rg(//) and Rg(?) are not fully relaxed when the stress and birefringence relax to zero. (d) Matrix molecular weight P effects on relaxation time ?(M) of the probe chain M are as follows: When the probe chain M>>P, the matrix P-chains percolate and Rouse-like dynamics is observed for the M-Reptating chains with ?(M) ˜ P1M2. (e) When the matrix P>>M, percolation does not occur for the M-chain and the relaxation time of the probe chain ?(M) ˜ PoM3 is in accord with DeGennes Reptation theory. These unusual results predicted by entanglement percolation are supported by extensive experimental data (NR, SANS, DSIMS, FTIR, BR) from selectively deuterated polystyrene chains HDH, DHD, HPS and DPS. These results clearly suggest that current notions of polymer rheology need to be reconsidered. Near Tg, a new perspective on the Glass Transition of amorphous materials is offered by the Twinkling Fractal Theory (TFT). [R. P. Wool, J. Polym. Sci, Part B: Polym Phys. 46, 2765 (2008)]. TFT applications to entangled polymers include: (a) rate dependence of dynamical mechanical properties, particularly the tan delta damping peak used to measure Tg, (b) derivation of the empirical WLF and Vogel Fulcher time-temperature superposition empirical relation, (c) Physical Aging and (d) Nanoconfinement.