WorldWideScience

Sample records for cyclic sieving phenomenon

  1. Tendon Contraction After Cyclic Elongation Is an Age-Dependent Phenomenon: In Vitro and In Vivo Comparisons.

    Science.gov (United States)

    Lavagnino, Michael; Bedi, Asheesh; Walsh, Christopher P; Sibilsky Enselman, Elizabeth R; Sheibani-Rad, Shahin; Arnoczky, Steven P

    2014-06-01

    Tendons are viscoelastic tissues that deform (elongate) in response to cyclic loading. However, the ability of a tendon to recover this elongation is unknown. Tendon length significantly increases after in vivo or in vitro cyclic loading, and the ability to return to its original length through a cell-mediated contraction mechanism is an age-dependent phenomenon. Controlled laboratory study. In vitro, rat tail tendon fascicles (RTTfs) from Sprague-Dawley rats of 3 age groups (1, 3, and 12 months) underwent 2% cyclic strain at 0.17 Hz for 2 hours, and the percentages of elongation were determined. After loading, the RTTfs were suspended for 3 days under tissue culture conditions and photographed daily to determine the amount of length contraction. In vivo, healthy male participants (n = 29; age, 19-49 years) had lateral, single-legged weightbearing radiographs taken of the knee at 60° of flexion immediately before, immediately after, and 24 hours after completing eccentric quadriceps loading exercises on the dominant leg to fatigue. Measurements of patellar tendon length were taken from the radiographs, and the percentages of tendon elongation and subsequent contraction were calculated. In vitro, cyclic loading increased the length of all RTTfs, with specimens from younger (1 and 3 months) rats demonstrating significantly greater elongation than those from older (12 months) rats (P = .009). The RTTfs contracted to their original length significantly faster (P fashion, with younger animals contracting faster. In vivo, repetitive eccentric loading exercises significantly increased patellar tendon length (P 30 years). Cyclic tendon loading results in a significant increase in tendon elongation under both in vitro and in vivo conditions. Tendons in both conditions demonstrated an incomplete return to their original length after 24 hours, and the extent of this return was age dependent. The age- and time-dependent contraction of tendons, elongated after repetitive

  2. Sieve methods

    CERN Document Server

    Halberstam, Heine

    2011-01-01

    Derived from the techniques of analytic number theory, sieve theory employs methods from mathematical analysis to solve number-theoretical problems. This text by a noted pair of experts is regarded as the definitive work on the subject. It formulates the general sieve problem, explores the theoretical background, and illustrates significant applications.""For years to come, Sieve Methods will be vital to those seeking to work in the subject, and also to those seeking to make applications,"" noted prominent mathematician Hugh Montgomery in his review of this volume for the Bulletin of the Ameri

  3. Sodium sieving in children

    NARCIS (Netherlands)

    Rusthoven, Esther; Krediet, Raymond T.; Willems, Hans L.; Monnens, Leo A.; Schröder, Cornelis H.

    2005-01-01

    Sodium sieving is a consequence of dissociation between the amount of water and sodium transported over the peritoneal membrane. This dissociation occurs in the presence of aquaporin-mediated water transport. Sieving of sodium can be used as a rough measure for aquaporin-mediated water transport.

  4. Massively parallel mathematical sieves

    Energy Technology Data Exchange (ETDEWEB)

    Montry, G.R.

    1989-01-01

    The Sieve of Eratosthenes is a well-known algorithm for finding all prime numbers in a given subset of integers. A parallel version of the Sieve is described that produces computational speedups over 800 on a hypercube with 1,024 processing elements for problems of fixed size. Computational speedups as high as 980 are achieved when the problem size per processor is fixed. The method of parallelization generalizes to other sieves and will be efficient on any ensemble architecture. We investigate two highly parallel sieves using scattered decomposition and compare their performance on a hypercube multiprocessor. A comparison of different parallelization techniques for the sieve illustrates the trade-offs necessary in the design and implementation of massively parallel algorithms for large ensemble computers.

  5. A vibration sieve

    Energy Technology Data Exchange (ETDEWEB)

    Alekhin, S.A.; Denisenko, V.V.; Dzhalalov, M.G.; Kirichek, F.P.; Pitatel, Yu.A.; Prokopov, L.I.; Tikhonov, Yu.P.

    1982-01-01

    A vibration sieve is proposed which includes a vibration drive, a body and a screen installed on shock absorbers, a device for washing out the screen, and a subassembly for loading the material. To increase the operational reliability and effectiveness of the vibration sieve by improving the cleaning of the screen, the loading subassembly is equipped with a baffle with a lever which is hinged to it. The device for washing out the screen is made in the form of an electromagnet with a connecting rod, a switch and an eccentric, a friction ratchet mechanism and sprinkling systems. Here, the latter are interconnected, using a connecting rod, while the sprinkling system is installed on rollers under the screen. The electromagnetic switch is installed under the lever. The body is made with grooves for installing the sprinkling system. The vibration sieve is equipped with a switch which interacts with the connecting rod. The friction ratchet mechanism is equipped with a lug.

  6. Microfluidic sieve valves

    Science.gov (United States)

    Quake, Stephen R; Marcus, Joshua S; Hansen, Carl L

    2015-01-13

    Sieve valves for use in microfluidic device are provided. The valves are useful for impeding the flow of particles, such as chromatography beads or cells, in a microfluidic channel while allowing liquid solution to pass through the valve. The valves find particular use in making microfluidic chromatography modules.

  7. Optimization Analysis on Parameters of Cleaning Sieve of Rape Combine of "Bi Lang 4LZ(Y)-1.0"

    OpenAIRE

    Wu Mingliang; Tang Lun; Guan Chunyun; Tang Chuzhou

    2014-01-01

    Against the phenomenon of high impurity rate and cane and pod shell are difficult to discharge at the end of the sieve for rape combine of "Bi Lang 4LZ(Y)-1.0". This study take cleaning sieve of rape combine of "Bi Lang 4LZ(Y)-1.0" as study object, analyzed the movement of materials on sieve, established the virtual prototype model of the cleaning sieve of this rape combine, taken materials and cleaning sieve all at the best motion state as constraint conditions and optimized the structure an...

  8. Microwave regeneration of molecular sieves

    International Nuclear Information System (INIS)

    Singh, V.P.

    1984-05-01

    Molecular sieve driers have been included in the design of tritium handling systems for fusion reactors. In these systems there is a need to maintain extremely low exit dew points from the driers as well as a capability to rapidly reduce tritium concentrations following an accident. The required capacity of the driers is very high. The conventional method of regenerating these sieves after a water adsorption cycle is with hot air. However, because water is rapidly heated by microwave energy, this technology may be suitable for decreasing the bed regeneration time and hence may allow reduced capital and operating costs associated with a smaller bed. The present study was conducted to obtain preliminary information on the technical feasibility of regenerating molecular sieves with microwave energy. The study concentrated on Type 4A molecular sieve with a few tests on Type 13X sieve and also a silica gel adsorbent

  9. Mole sieve cycle optimization

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, P. [Petro-Canada Oil and Gas, Inc., Calgary, AB (Canada)

    2004-07-01

    Maturing gas basins and declining reservoirs have prompted the search for energy and cost reduction initiatives to maintain operation sustainability. This paper discusses the development of an algorithm to improve the efficiency of the Brazeau mole sieve dehydration system. Details of the operating unit and an outline of the system were provided, as well as an operator interface. The main objectives of the research were to reduce the number of corresponding regeneration cycles; reduce annual energy requirements; and extend the life of the dessicant. Reductions were anticipated at 35 per cent, leading towards fuel savings of $45,000 a year, and carbon dioxide reductions of 670 tonnes a year. However, significant barriers were also noted, including operations, maintenance and equipment replacement issues. Equations of state were used to estimate vapor pressure or water content in gases. Approximate water content was measured with gas flow rate. The resulting algorithm was implemented using a basic best fit curve generated for one variable with a correction factor applied as a second variable. Data books were provided to present water content of hydrocarbon gas, with implementation procedures. Benefits of the new system included longer service life and reduced chemical and outside service costs, and reduced lost production during sieve changes. Additional benefits included enhanced distributed computing system (DCS) interfaces within plant operations; extension of the adsorption cycle via the functionality of the algorithm; and the fact that during a plant upset, the algorithm froze cycle sequencing and eliminated the possibility of switching the beds and repeating regeneration. The improved system resulted in savings of $87,000. tabs, figs.

  10. Raynaud's phenomenon

    DEFF Research Database (Denmark)

    Nielsen, S L; Christensen, N J; Olsen, N

    1980-01-01

    . The forearm venous concentration of noradrenaline was lower and adrenaline concentration higher in the sympathectomized patients than in the other groups (p less than 0,05). Noradrenaline showed a significant increase during body cooling in normals and primary Raynaud's (p less than 0......The reaction to body and finger cooling was recorded in seven patients with relapse of primary Raynaud's phenomenon after sufficiently performed bilateral upper thoracic sympathectomy and for comparison in eight young women with primary Raynaud's phenomenon as well as in seven normal women......,05). There was no significant correlation between the vasoconstrictor response to cooling of a finger and the noradrenaline concentration probably due to the fact that skin vasoconstriction impeded release of noradrenaline from the skin. The relapse of Raynaud's phenomenon after surgically sufficient sympathectomy could...

  11. Multiprocessing the Sieve of Eratosthenes

    Energy Technology Data Exchange (ETDEWEB)

    Bokhari, S.H.

    1987-04-01

    More than two thousand years ago, Eratosthenes of Cyrene described a procedure for finding all prime numbers in a given range. This straightforward algorithm, known as the Sieve of Eratosthenes, is to this day the only procedure for finding prime numbers. In recent years it has been of interest to computer scientists and engineers because it serves as a convenient benchmark against which to measure some aspects of a computer's performance. Specifically, the Sieve tests the power of a machine (or of a compiler) to access a very large array in memory rapidly and repeatedly. This power is clearly influenced by memory access time, the speed at which indexing is done, and the overhead of looping. The parallel version of the Sieve is very useful as a test of some of the capabilities of a parallel machine. The parallel algorithm is straightforward, and so is the process for checking the final results. However, the efficient implementation of the algorithm on a real parallel machine, especially in the dynamic load-balancing case, requires thoughtful design.

  12. Why are carbon molecular sieves interesting?

    Directory of Open Access Journals (Sweden)

    Oliveira Erica C. de

    2006-01-01

    Full Text Available This paper describes the production methods and the prospective uses of carbon molecular sieves. The main route to these materials is replication synthesis, where a silica or aluminosilicate molecular sieve is used as template to grow the carbonaceous phase in the voids. These materials may have applications as varied as in separation, adsorption and storage of gases, as electrodes in batteries, and as catalyst supports, all of them highly dependent on the molecular sieve porosity.

  13. Multiprocessing the Sieve of Eratosthenes

    Science.gov (United States)

    Bokhari, S.

    1986-01-01

    The Sieve of Eratosthenes for finding prime numbers in recent years has seen much use as a benchmark algorithm for serial computers while its intrinsically parallel nature has gone largely unnoticed. The implementation of a parallel version of this algorithm for a real parallel computer, the Flex/32, is described and its performance discussed. It is shown that the algorithm is sensitive to several fundamental performance parameters of parallel machines, such as spawning time, signaling time, memory access, and overhead of process switching. Because of the nature of the algorithm, it is impossible to get any speedup beyond 4 or 5 processors unless some form of dynamic load balancing is employed. We describe the performance of our algorithm with and without load balancing and compare it with theoretical lower bounds and simulated results. It is straightforward to understand this algorithm and to check the final results. However, its efficient implementation on a real parallel machine requires thoughtful design, especially if dynamic load balancing is desired. The fundamental operations required by the algorithm are very simple: this means that the slightest overhead appears prominently in performance data. The Sieve thus serves not only as a very severe test of the capabilities of a parallel processor but is also an interesting challenge for the programmer.

  14. Comparative Modal Analysis of Sieve Hardware Designs

    Science.gov (United States)

    Thompson, Nathaniel

    2012-01-01

    The CMTB Thwacker hardware operates as a testbed analogue for the Flight Thwacker and Sieve components of CHIMRA, a device on the Curiosity Rover. The sieve separates particles with a diameter smaller than 150 microns for delivery to onboard science instruments. The sieving behavior of the testbed hardware should be similar to the Flight hardware for the results to be meaningful. The elastodynamic behavior of both sieves was studied analytically using the Rayleigh Ritz method in conjunction with classical plate theory. Finite element models were used to determine the mode shapes of both designs, and comparisons between the natural frequencies and mode shapes were made. The analysis predicts that the performance of the CMTB Thwacker will closely resemble the performance of the Flight Thwacker within the expected steady state operating regime. Excitations of the testbed hardware that will mimic the flight hardware were recommended, as were those that will improve the efficiency of the sieving process.

  15. Sieve tube geometry in relation to phloem flow

    NARCIS (Netherlands)

    Mullendore, D.L.; Windt, C.W.; As, van H.; Knoblauch, M.

    2010-01-01

    Sieve elements are one of the least understood cell types in plants. Translocation velocities and volume flow to supply sinks with photoassimilates greatly depend on the geometry of the microfluidic sieve tube system and especially on the anatomy of sieve plates and sieve plate pores. Several models

  16. Modeling the hydrodynamics of Phloem sieve plates

    DEFF Research Database (Denmark)

    Jensen, Kaare Hartvig; Mullendore, Daniel Leroy; Holbrook, Noel Michele

    2012-01-01

    Sieve plates have an enormous impact on the efficiency of the phloem vascular system of plants, responsible for the distribution of photosynthetic products. These thin plates, which separate neighboring phloem cells, are perforated by a large number of tiny sieve pores and are believed to play...... understood. We propose a theoretical model for quantifying the effect of sieve plates on the phloem in the plant, thus unifying and improving previous work in the field. Numerical simulations of the flow in real and idealized phloem channels verify our model, and anatomical data from 19 plant species...... a crucial role in protecting the phloem sap from intruding animals by blocking flow when the phloem cell is damaged. The resistance to the flow of viscous sap in the phloem vascular system is strongly affected by the presence of the sieve plates, but the hydrodynamics of the flow through them remains poorly...

  17. Constellations of gaps in Eratosthenes sieve

    OpenAIRE

    Holt, Fred B.

    2015-01-01

    A few years ago we identified a recursion that works directly with the gaps among the generators in each stage of Eratosthenes sieve. This recursion provides explicit enumerations of sequences of gaps among the generators, which sequences are known as constellations. Over the last year we identified a discrete linear system that exactly models the population of any gap across all stages of the sieve. In August 2014 we summarized our results from analyzing this discrete model on populations of...

  18. Modeling the hydrodynamics of phloem sieve plates

    Directory of Open Access Journals (Sweden)

    Kaare Hartvig Jensen

    2012-07-01

    Full Text Available Sieve plates have an enormous impact on the efficiency of the phloem vascular system of plants, responsible for the distribution of photosynthetic products. These thin plates, which separate neighboring phloem cells, are perforated by a large number of tiny sieve pores and are believed to play a crucial role in protecting the phloem sap from intruding animals by blocking flow when the phloem cell is damaged. The resistance to the flow of viscous sap in the phloem vascular system is strongly affected by the presence of the sieve plates, but the hydrodynamics of the flow through them remains poorly understood. We propose a theoretical model for quantifying the effect of sieve plates on the phloem in the plant, thus unifying and improving previous work in the field. Numerical simulations of the flow in real and idealized phloem channels verify our model, and anatomical data from 19 plant species are investigated. We find that the sieve plate resistance is correlated to the cell lumen resistance, and that the sieve plate and the lumen contribute almost equally to the total hydraulic resistance of the phloem translocation pathway.

  19. Microporous and meso porous molecular sieves

    International Nuclear Information System (INIS)

    Araujo, Antonio Souza de

    1999-01-01

    In this work, general aspects on the microporous and mesoporous molecular sieves using inorganic sources of aluminium, silicon, phosphorous, water and structural organic templates are reviewed. The nomenclature, synthesis, structure, acidity and chemical functionality of microporous zeolites and silico alumino phosphate, besides mesoporous MCM-41 material, will be emphasized. (author)

  20. Gamma scanning of large sieve tray towers

    International Nuclear Information System (INIS)

    McCaw, D.D.; Hulbert, V.G.; Smith, A.E.

    1976-01-01

    A special instrument based on the use of gamma rays, has been developed, which assists in the evaluation of the effects of changes in controlled variables on sieve tray performance. Internal structural damage, and local tray flooding are readily detectable from outside the vessel. The instrument is described, and examples of its use are given. (author)

  1. Nanotechnology for membranes, filters and sieves

    NARCIS (Netherlands)

    Eijkel, Jan C.T.; van den Berg, Albert

    2006-01-01

    This mini-review is dedicated to the use of nanotechnology for membranes, filters and sieves. With the advent of nanotechnology researchers have acquired an unprecedented freedom to sculpt device geometry almost down to the molecular scale. Such structures can now replace the gels, membranes and

  2. Recent Improvements To the Sieve of Eratosthenes.

    Science.gov (United States)

    Quesada, Antonio R.

    1997-01-01

    Presents recently developed generalizations to the sieve of Eratosthenes, showing the principles underlying these improvements, which increase its efficiency without changing too much of its simplicity. Offers several possibilities to propose good investigations for students to explore, find patterns, and make generalizations. (JRH)

  3. Design, Construction and Testing of a Dry Sand Sieving Machine ...

    African Journals Online (AJOL)

    This paper reports on the design, construction and Testing of a dry sand sieving machine. The sample to be sieved is uniformly graded. The coefficient of uniformity is 1.11, thus the machine design does not sieve larger particles such as gravel. The slip calculated is 36% which enabled the proper configuration of the V-belt.

  4. Adsorption of moisture on molecular sieve adsorbents at low humidity

    International Nuclear Information System (INIS)

    Singh, V.P.; Ruthven, D.M.

    1984-07-01

    This report summarizes the results and conclusions of a contractor's study on the performance of 4A molecular sieve under very low humidity conditions, e.g., as expected in fusion reactor plants. The results suggest that: (a) very efficient regeneration of the sieve to low residual moisture contents ( 2 O/4A sieve system

  5. 7 CFR 801.8 - Tolerances for sieves.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Tolerances for sieves. 801.8 Section 801.8 Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION, PACKERS AND STOCKYARD... FOR GRAIN INSPECTION EQUIPMENT § 801.8 Tolerances for sieves. The maintenance tolerances for sieves...

  6. Models of Prime-Like Sequences Generated by Least Element Sieve Operations Like the Sieve of Eratosthenes

    OpenAIRE

    Baum, Leonard E.

    2017-01-01

    We suggest other models of sieve generated sequences like the Sieve of Eratosthenes to explain randomness properties of the prime numbers, like the twin prime conjecture, the lim sup conjecture, the Riemann conjecture, and the prime number theorem.

  7. Cyclic multiverses

    Science.gov (United States)

    Marosek, Konrad; Dąbrowski, Mariusz P.; Balcerzak, Adam

    2016-09-01

    Using the idea of regularization of singularities due to the variability of the fundamental constants in cosmology we study the cyclic universe models. We find two models of oscillating and non-singular mass density and pressure (`non-singular' bounce) regularized by varying gravitational constant G despite the scale factor evolution is oscillating and having sharp turning points (`singular' bounce). Both violating (big-bang) and non-violating (phantom) null energy condition models appear. Then, we extend this idea on to the multiverse containing cyclic individual universes with either growing or decreasing entropy though leaving the net entropy constant. In order to get an insight into the key idea, we consider the doubleverse with the same geometrical evolution of the two `parallel' universes with their physical evolution [physical coupling constants c(t) and G(t)] being different. An interesting point is that there is a possibility to exchange the universes at the point of maximum expansion - the fact which was already noticed in quantum cosmology. Similar scenario is also possible within the framework of Brans-Dicke theory where varying G(t) is replaced by the dynamical Brans-Dicke field φ(t) though these theories are slightly different.

  8. On the occurrence of nuclei in mature sieve elements.

    Science.gov (United States)

    Event, R F; Davis, J D; Tucker, C M; Alfieri, F J

    1970-12-01

    The secondary phloem of 3 species of the Taxodiaceae and 13 species of woody dicotyledons was examined for the occurrence of nuclei in mature sieve elements. Nuclei were found in all mature sieve cells of Metasequoia glyptostroboides, Sequoia sempervirens and Taxodium distichum, and in some mature sieve-tube members in 12 of the 13 species of woody dicotyledons. Except for nuclei of sieve cells undergoing cessation of function, the nuclei in mature sieve cells of M. glyptostroboides, S. sempervirens and T. distichum were normal in appearance. The occurrence and morphology of nuclei in mature sieve-tube members of the woody dicotyledons were quite variable. Only 3 species, Robinia pseudoacacia, Ulmus americana and Vitis riparia, contained some mature sieve elements with apparently normal nuclei.

  9. Vitrification of spent mordenite molecular sieves

    International Nuclear Information System (INIS)

    Sathi Sasidharan, N.; Deshingkar, D.S.; Jain, Savita; Singh, I.J.; Wattal, P.K.

    2002-11-01

    Vitrification of cesium loaded inorganic ion exchangers (mordenite type molecular sieves/zeolite AR-1) was studied empolying borosilicate glass systems. Direct vitrification of aluminosilicates is rather difficult mainly on account of volatility of cesium at processing temperatures of 1100 degC-1300 degC. In the borosilicate glass system, oxides of lead, sodium and zinc along with boric oxide were employed as major glass formers. Homogeneous glass matrix was obtained incorporating simulated composition of mordenite along with oxides of sodium, lead and boron at the processing temperature of 950 degC. The waste oxide loading up to 50% on dry weight basis was incorporated in this glass formulation. Partial replacement of PbO by TeO 2 , Bi 2 O 3 and CaF 2 resulted in lowering of the processing temperature and also increasing homogeneity of matrix. Based on these results, a glass matrix was prepared with actual cesium AR-1 molecular sieves with processing temperature limited to 925 degC. Powdered samples of glass matrix were subjected to leaching as per ASTM-1285 Product Consistency Test in high purity water at 90 degC for 28 days. The normalised cesium leach rate of this glass was found to be 3.92 x 10 -6 g/cm 2 /day, which is comparable to sodium borosilicate glass matrices currently in use for immobilisation of high level waste. The molecular sieves are also amenable to immobilization in cement matrix. As expected, there is substantial volume reduction by factor 3 in vitrification compared to their immobilization in cementious matrices. Also the quantity of cesium leached from vitrified product was nearly 10,000 times lower compared to cement based matrix. Vitrification of mordenite molecular sieves would lead to high capacity utilisation of zeolite AR-1 for the treatment of low and intennediate levelliquid effluents. (author)

  10. The impostor phenomenon

    DEFF Research Database (Denmark)

    Ringby, Betina; Østergaard, Gert Værge; Bønnelykke, Helle

    Persons suffering from the impostor phenomenon often fail to thrive and might be in danger of dropping out of studies. The impostor-phenomenon relates to people who are both skillful and capable, but sees themselves as frauds and as someone who is not worthy of good grades, appraisal for their work...

  11. Sieve Tube Geometry in Relation to Phloem Flow

    Science.gov (United States)

    Mullendore, Daniel L.; Windt, Carel W.; Van As, Henk; Knoblauch, Michael

    2010-01-01

    Sieve elements are one of the least understood cell types in plants. Translocation velocities and volume flow to supply sinks with photoassimilates greatly depend on the geometry of the microfluidic sieve tube system and especially on the anatomy of sieve plates and sieve plate pores. Several models for phloem translocation have been developed, but appropriate data on the geometry of pores, plates, sieve elements, and flow parameters are lacking. We developed a method to clear cells from cytoplasmic constituents to image cell walls by scanning electron microscopy. This method allows high-resolution measurements of sieve element and sieve plate geometries. Sieve tube–specific conductivity and its reduction by callose deposition after injury was calculated for green bean (Phaseolus vulgaris), bamboo (Phyllostachys nuda), squash (Cucurbita maxima), castor bean (Ricinus communis), and tomato (Solanum lycopersicum). Phloem sap velocity measurements by magnetic resonance imaging velocimetry indicate that higher conductivity is not accompanied by a higher velocity. Studies on the temporal development of callose show that small sieve plate pores might be occluded by callose within minutes, but plants containing sieve tubes with large pores need additional mechanisms. PMID:20354199

  12. Prime Numbers Comparison using Sieve of Eratosthenes and Sieve of Sundaram Algorithm

    Science.gov (United States)

    Abdullah, D.; Rahim, R.; Apdilah, D.; Efendi, S.; Tulus, T.; Suwilo, S.

    2018-03-01

    Prime numbers are numbers that have their appeal to researchers due to the complexity of these numbers, many algorithms that can be used to generate prime numbers ranging from simple to complex computations, Sieve of Eratosthenes and Sieve of Sundaram are two algorithm that can be used to generate Prime numbers of randomly generated or sequential numbered random numbers, testing in this study to find out which algorithm is better used for large primes in terms of time complexity, the test also assisted with applications designed using Java language with code optimization and Maximum memory usage so that the testing process can be simultaneously and the results obtained can be objective

  13. Interfacial phenomenon theory

    International Nuclear Information System (INIS)

    Kim, Jong Deuk

    2000-02-01

    This book is composed of 8 chapters. It tells what interfacial phenomenon is by showing interfacial energy, characteristic of interface and system of interface from chapter 1. It also introduces interfacial energy and structure theory, molecular structure and orientation theory, and interfacial electricity phenomenon theory in the following 3 chapters. It still goes on by introducing super molecule cluster, disequilibrium dispersion, and surface and film through 3 chapters. And the last chapter is about colloid and application of interface.

  14. Active sieving across driven nanopores for tunable selectivity

    Science.gov (United States)

    Marbach, Sophie; Bocquet, Lydéric

    2017-10-01

    Molecular separation traditionally relies on sieving processes across passive nanoporous membranes. Here we explore theoretically the concept of non-equilibrium active sieving. We investigate a simple model for an active noisy nanopore, where gating—in terms of size or charge—is externally driven at a tunable frequency. Our analytical and numerical results unveil a rich sieving diagram in terms of the forced gating frequency. Unexpectedly, the separation ability is strongly increased as compared to its passive (zero frequency) counterpart. It also points to the possibility of tuning dynamically the osmotic pressure. Active separation outperforms passive sieving and represents a promising avenue for advanced filtration.

  15. Ultrathin graphene-based membrane with precise molecular sieving and ultrafast solvent permeation

    Science.gov (United States)

    Yang, Q.; Su, Y.; Chi, C.; Cherian, C. T.; Huang, K.; Kravets, V. G.; Wang, F. C.; Zhang, J. C.; Pratt, A.; Grigorenko, A. N.; Guinea, F.; Geim, A. K.; Nair, R. R.

    2017-12-01

    Graphene oxide (GO) membranes continue to attract intense interest due to their unique molecular sieving properties combined with fast permeation. However, their use is limited to aqueous solutions because GO membranes appear impermeable to organic solvents, a phenomenon not yet fully understood. Here, we report efficient and fast filtration of organic solutions through GO laminates containing smooth two-dimensional (2D) capillaries made from large (10-20 μm) flakes. Without modification of sieving characteristics, these membranes can be made exceptionally thin, down to ~10 nm, which translates into fast water and organic solvent permeation. We attribute organic solvent permeation and sieving properties to randomly distributed pinholes interconnected by short graphene channels with a width of 1 nm. With increasing membrane thickness, organic solvent permeation rates decay exponentially but water continues to permeate quickly, in agreement with previous reports. The potential of ultrathin GO laminates for organic solvent nanofiltration is demonstrated by showing >99.9% rejection of small molecular weight organic dyes dissolved in methanol. Our work significantly expands possibilities for the use of GO membranes in purification and filtration technologies.

  16. Arithmetical aspects of the large sieve inequality

    CERN Document Server

    2009-01-01

    This book is an elaboration of a series of lectures given at the Harish-Chandra Research Institute. The reader will be taken through a journey on the arithmetical sides of the large sieve inequality when applied to the Farey dissection. This will reveal connections between this inequality, the Selberg sieve and other less used notions like pseudo-characters and the $\\Lambda_Q$-function, as well as extend these theories. One of the leading themes of these notes is the notion of so-called\\emph{local models} that throws a unifying light on the subject. As examples and applications, the authors present, among other things, an extension of the Brun-Tichmarsh Theorem, a new proof of Linnik's Theorem on quadratic residues and an equally novel one of the Vinogradov three primes Theorem; the authors also consider the problem of small prime gaps, of sums of two squarefree numbers and several other ones, some of them being new, like a sharp upper bound for the number of twin primes $p$ that are such that $p+1$ is square...

  17. Reassessing molecular sieving by kinked carbon nanotubes

    International Nuclear Information System (INIS)

    Zhang, Zhongqiang; Ding, Jianning; Cheng, Guanggui; Ling, Zhiyong; Zhang, Hongwu; Zheng, Yonggang; Ye, Hongfei; Wang, Lei; Wang, Jinbao; Liu, Zhen

    2011-01-01

    Based on molecular dynamics simulations for the transport of pure nitrogen (N 2 ), oxygen (O 2 ) and their mixture in kinked single-walled carbon nanotubes (SWCNTs), molecular sieving by the kinked model of SWCNTs is presented. The influences of gas pressure, temperature and the component ratio of N 2 in the mixture on gas separation are investigated. Considering the tradeoff between the permeability and the purity of O 2 , the results show that a large gas pressure, 300–500 K of gas temperature and a low component ratio of N 2 in the N 2 –O 2 mixture can be advantageous to the efficiency of gas separation. The purity of O 2 can be kept higher than 80% when the component ratio of N 2 is lower than 3/4, which will be advantageous to the design of multi-level gas separation mechanisms. The findings may provide theoretical references for the design and manufacture of molecular sieving devices in engineering applications

  18. Computational sieving applied to some classical number-theoretic problems

    NARCIS (Netherlands)

    H.J.J. te Riele (Herman)

    1998-01-01

    textabstractMany problems in computational number theory require the application of some sieve. Efficient implementation of these sieves on modern computers has extended our knowledge of these problems considerably. This is illustrated by three classical problems: the Goldbach conjecture, factoring

  19. Interactions among tobacco sieve element occlusion (SEO) proteins.

    Science.gov (United States)

    Jekat, Stephan B; Ernst, Antonia M; Zielonka, Sascia; Noll, Gundula A; Prüfer, Dirk

    2012-12-01

    Angiosperms transport their photoassimilates through sieve tubes, which comprise longitudinally-connected sieve elements. In dicots and also some monocots, the sieve elements contain parietal structural proteins known as phloem proteins or P-proteins. Following injury, P proteins disperse and accumulate as viscous plugs at the sieve plates to prevent the loss of valuable transport sugars. Tobacco (Nicotiana tabacum) P-proteins are multimeric complexes comprising subunits encoded by members of the SEO (sieve element occlusion) gene family. The existence of multiple subunits suggests that P-protein assembly involves interactions between SEO proteins, but this process is largely uncharacterized and it is unclear whether the different subunits perform unique roles or are redundant. We therefore extended our analysis of the tobacco P-proteins NtSEO1 and NtSEO2 to investigate potential interactions between them, and found that both proteins can form homomeric and heteromeric complexes in planta.

  20. Phenomenon detection device

    International Nuclear Information System (INIS)

    Suzuki, Yasuo.

    1994-01-01

    Detection signals for a specific phenomenon outputted from any of detectors are distributed by way of half mirrors and inputted to a logic discrimination circuit by way of a photoelectric convertor. The photoelectric convertor detects the quantity of light corresponding to the optical signals from more than two detectors which detected the phenomenon, and outputs detection signals to the logic discrimination circuit. If the phenomenon is detected, since both inputs turn ON in the logic discrimination circuit in accordance with the predetermined logical sum, the occurrence of a specific phenomenon is detected. Thus, an optical system substantially comprises half mirrors, reflection mirrors and photoelectric convertor in combination provides a logic circuit. Since the circuit which transmits signals of the detectors is constituted with an optical system using the half mirrors, the number of parts constituting the logic circuit can greatly be saved. In addition, since the optical system comprises mirrors or half mirrors which have been used so far, they can be used, once assembled, quasipermanently, and the reliability can be enhanced greatly. (N.H.)

  1. Mask Phenomenon in Communication

    Institute of Scientific and Technical Information of China (English)

    郎丽璇

    2013-01-01

    People sometimes wear masks. Abusive expression may be used to convey love while polite words can be exchanged among enemies. This essay describes and discusses this special phenomenon in communication and analyzes the elements that con-tribute to the success of a mask communication.

  2. On ciliary pumping and sieving in bryozoans

    DEFF Research Database (Denmark)

    Larsen, Poul Scheel; Riisgård, H. U.

    2002-01-01

    to be transferred to and conveyed by the frontal cilia bands on tentacles. The added load on laterofrontal cilia from viscous drag on a food particle retained by the cilia is found to be of the same order of magnitude or greater than the "background load" of viscous drag from fluid passing the laterofrontal cilia...... flicks, a description is given of the feeding mechanisms. Particles entering the central region are brought to the mouth by the high velocity feeding current in the central part of the lophophore. Particles entering further out either escape between tentacles or are stopped by the laterofrontal cilia...... sieve and, in the distal region of tentacles, are brought back into the central feeding current by flicks of tentacles. The relative velocity between fluid and particle during a flick recovery phase ensures particle release. Particles stopped in the proximal region of the lophophore appear...

  3. Octahedral molecular sieve sorbents and catalysts

    Science.gov (United States)

    Li, Liyu [Richland, WA; King, David L [Richland, WA

    2010-04-20

    Octahedral molecular sieve sorbents and catalysts are disclosed, including silver hollandite and cryptomelane. These materials can be used, for example, to catalyze the oxidation of CO.sub.x (e.g., CO), NO.sub.x (e.g., NO), hydrocarbons (e.g., C.sub.3H.sub.6) and/or sulfur-containing compounds. The disclosed materials also may be used to catalyze other reactions, such as the reduction of NO.sub.2. In some cases, the disclosed materials are capable of sorbing certain products from the reactions they catalyze. Silver hollandite, in particular, can be used to remove a substantial portion of certain sulfur-containing compounds from a gas or liquid by catalysis and/or sorption. The gas or liquid can be, for example, natural gas or a liquid hydrocarbon.

  4. Recent Advances on Carbon Molecular Sieve Membranes (CMSMs and Reactors

    Directory of Open Access Journals (Sweden)

    Margot A. Llosa Tanco

    2016-08-01

    Full Text Available Carbon molecular sieve membranes (CMSMs are an important alternative for gas separation because of their ease of manufacture, high selectivity due to molecular sieve separation, and high permeance. The integration of separation by membranes and reaction in only one unit lead to a high degree of process integration/intensification, with associated benefits of increased energy, production efficiencies and reduced reactor or catalyst volume. This review focuses on recent advances in carbon molecular sieve membranes and their applications in membrane reactors.

  5. SieveSifter: a web-based tool for visualizing the sieve analyses of HIV-1 vaccine efficacy trials.

    Science.gov (United States)

    Fiore-Gartland, Andrew; Kullman, Nicholas; deCamp, Allan C; Clenaghan, Graham; Yang, Wayne; Magaret, Craig A; Edlefsen, Paul T; Gilbert, Peter B

    2017-08-01

    Analysis of HIV-1 virions from participants infected in a randomized controlled preventive HIV-1 vaccine efficacy trial can help elucidate mechanisms of partial protection. By comparing the genetic sequence of viruses from vaccine and placebo recipients to the sequence of the vaccine itself, a technique called 'sieve analysis', one can identify functional specificities of vaccine-induced immune responses. We have created an interactive web-based visualization and data access tool for exploring the results of sieve analyses performed on four major preventive HIV-1 vaccine efficacy trials: (i) the HIV Vaccine Trial Network (HVTN) 502/Step trial, (ii) the RV144/Thai trial, (iii) the HVTN 503/Phambili trial and (iv) the HVTN 505 trial. The tool acts simultaneously as a platform for rapid reinterpretation of sieve effects and as a portal for organizing and sharing the viral sequence data. Access to these valuable datasets also enables the development of novel methodology for future sieve analyses. Visualization: http://sieve.fredhutch.org/viz . Source code: https://github.com/nkullman/SIEVE . Data API: http://sieve.fredhutch.org/data . agartlan@fredhutch.org. © The Author(s) 2017. Published by Oxford University Press.

  6. WORKPLACE HARASSMENT. MOBBING PHENOMENON

    Directory of Open Access Journals (Sweden)

    Marius Ezer

    2012-11-01

    Full Text Available Moral harassment at the workplace has become in the last period a very often met phenomenon that severely affects the work relations and represents a significant health and safety danger. This problem has become in the last period an important issue for the European Union which has initiated a series of studie for analyzing the consequences of this pehenomenon on the normal process of the work relations, that has lead, in its turn to an awareness of this new dimenion of harassment between the employees at the internal level.

  7. Theoretical and experimental fundamentals of the test-sieving and investigations of the sieving properties of UO2-powder

    International Nuclear Information System (INIS)

    Stolle, W.; Henke, M.

    1983-02-01

    The results of sieve analyses may be interpreted in the best manner by approximate functions which permit the exact description of the grain size distributions by two parameters. This fact facilitates the comparison of results of size analyses essentially and enables their graphical representation in form of linear size-distributions curves. The deviations of the linearity refer to irregularities in the powder preparation or in the powder processing. Investigations of UO 2 -powders by dry sieve analysis have shown that it is possible to classify such powders in the range of grain sizes of more than 63 micrometers, in which specific sieving conditions must be find out for each special material. (author)

  8. The logics behind isomorphous substitution in molecular sieves

    International Nuclear Information System (INIS)

    Pastore, Heloise de O.

    1986-01-01

    The concept of an ideal molecular sieve framework as being ionic and having all its components in a tetrahedral configuration is reconsidered based on the weath of compositions/structures now available. (author)

  9. Selective molecular sieving through porous graphene.

    Science.gov (United States)

    Koenig, Steven P; Wang, Luda; Pellegrino, John; Bunch, J Scott

    2012-11-01

    Membranes act as selective barriers and play an important role in processes such as cellular compartmentalization and industrial-scale chemical and gas purification. The ideal membrane should be as thin as possible to maximize flux, mechanically robust to prevent fracture, and have well-defined pore sizes to increase selectivity. Graphene is an excellent starting point for developing size-selective membranes because of its atomic thickness, high mechanical strength, relative inertness and impermeability to all standard gases. However, pores that can exclude larger molecules but allow smaller molecules to pass through would have to be introduced into the material. Here, we show that ultraviolet-induced oxidative etching can create pores in micrometre-sized graphene membranes, and the resulting membranes can be used as molecular sieves. A pressurized blister test and mechanical resonance are used to measure the transport of a range of gases (H(2), CO(2), Ar, N(2), CH(4) and SF(6)) through the pores. The experimentally measured leak rate, separation factors and Raman spectrum agree well with models based on effusion through a small number of ångstrom-sized pores.

  10. Electron beam irradiation effect on nanostructured molecular sieve catalysts

    International Nuclear Information System (INIS)

    Yuan Zhongyong; Zhou Wuzong; Parvulescu, Viorica; Su Baolian

    2003-01-01

    Electron impact can induce chemical changes on particle surfaces of zeolites and molecular sieve catalysts. Some experimental observations of electron irradiation effect on molecular sieve catalysts are presented, e.g., electron-beam-induced growth of bare silver nanowires from zeolite crystallites, formation of vesicles in calcium phosphate, migration of microdomains in iron-oxide doped mesoporous silicas, structural transformation from mesostructured MCM-41 to microporous ZSM-5, etc. The formation mechanisms of the surface structures are discussed

  11. Adsorption methods for hydrogen isotope storage on zeolite sieves

    International Nuclear Information System (INIS)

    Cristescu, Ioana; Cristescu, Ion; Vasut, Felicia; Brad, Sebastian; Lazar, Alin

    2001-01-01

    Adsorption molecular sieves and activated carbon were used for hydrogen isotopes. The adsorption process proceeds at liquid nitrogen and liquid hydrogen temperatures. The synthetic zeolites have similar properties as natural zeolites, but they have a regular pore structure and affinity for molecules of different size with defined shapes. Experimental results obtained at liquid nitrogen and liquid hydrogen temperatures evidenced the efficient behavior of the activated carbon and zeolite sieves for hydrogen isotope temporary storage. (authors)

  12. Adsorption of hydrogen and deuterium on modified molecular sieves

    International Nuclear Information System (INIS)

    Li Jing; Shi Jinsong; Wu Erdong; Li Xiongwei; Peng Lixia

    2013-01-01

    The adsorption characteristics of hydrogen isotopes on 5A, ZSM-5 and their modified molecular sieves were studied at liquid nitrogen temperature with volumetric method. The effects of modification methods such as transition metal salt loading and ball milling on the adsorption behavior were discussed. It is observed that the adsorption amounts on the modified molecular sieves are reduced. but some modifications contribute to the separation between H 2 and D 2 . (authors)

  13. Rigorous Analysis of a Randomised Number Field Sieve

    OpenAIRE

    Lee, Jonathan; Venkatesan, Ramarathnam

    2018-01-01

    Factorisation of integers $n$ is of number theoretic and cryptographic significance. The Number Field Sieve (NFS) introduced circa 1990, is still the state of the art algorithm, but no rigorous proof that it halts or generates relationships is known. We propose and analyse an explicitly randomised variant. For each $n$, we show that these randomised variants of the NFS and Coppersmith's multiple polynomial sieve find congruences of squares in expected times matching the best-known heuristic e...

  14. Determination of sieve grading curves using an optical device

    OpenAIRE

    PHAM, AM; DESCANTES, Yannick; DE LARRARD, François

    2011-01-01

    The grading curve of an aggregate is a fundamental characteristic for mix design that can easily be modified to adjust several mix properties. While sieve analysis remains the reference method to determine this curve, optical devices are developing, allowing easier and faster assessment of aggregate grading. Unfortunately, optical grading results significantly differ from sieve grading curves. As a consequence, getting full acceptance of these new methods requires building bridges between the...

  15. A Geometric View of the Sieve of Eratosthenes

    OpenAIRE

    Iosif, Alexandru

    2011-01-01

    We study the geometry of the Sieve of Eratosthenes. We introduce some concepts as Focals and Extremes. We find a symmetry in the distribution of the Focals (all the information about the primes is contained into a small set of numbers). We find that there is a geometric order in the Sieve and we give a formula for the greatest remainder that returns the same quotient.

  16. The statistical stability phenomenon

    CERN Document Server

    Gorban, Igor I

    2017-01-01

    This monograph investigates violations of statistical stability of physical events, variables, and processes and develops a new physical-mathematical theory taking into consideration such violations – the theory of hyper-random phenomena. There are five parts. The first describes the phenomenon of statistical stability and its features, and develops methods for detecting violations of statistical stability, in particular when data is limited. The second part presents several examples of real processes of different physical nature and demonstrates the violation of statistical stability over broad observation intervals. The third part outlines the mathematical foundations of the theory of hyper-random phenomena, while the fourth develops the foundations of the mathematical analysis of divergent and many-valued functions. The fifth part contains theoretical and experimental studies of statistical laws where there is violation of statistical stability. The monograph should be of particular interest to engineers...

  17. NO REFLOW PHENOMENON

    Directory of Open Access Journals (Sweden)

    Omid Hashemifard

    2010-11-01

    Full Text Available Definition No reflow is a phenomenon in which myocardial ischemia and reduced antegrade flow occur despite the absence of proximal stenosis, spasm, dissection, or embolic cut off of major distal branches.1 In another word no reflow phenomenon means failure of restoration of myocardial flow despite removal of epicardial coronary obstruction.2 The incidence is 2% with plain balloon angioplasty (PTCA, 7% in patients undergoing rotational atherectomy, 12% for primary percutaneous coronary intervention (PCI, and much higher at 42% for PCI of degenerated Saphenous Vein Graft (SVG.3 No reflow is a strong predictor of mortality after PCI. The mortality of patients who developed no reflow has been estimated to be 8% Predictors of no reflow include a higher plaque burden, thrombus, lipid pools by intra vascular ultra sonography (IVUS, higher lesion elastic membrane cross sectional area, preinfarction angina and thrombolysis in myocardial infarction (TIMI flow grade 0 on the initial coronary angiogram. Mechanism The cause is mainly embolization of atheromatous material (gruel. Particles are composed of cholesterol clefts, lipid rich macrophages, fragments of fibrous cap, necrotic lesion core and fibrin. This is aggravated by microembolization of platelet-rich thrombi that release vasoactive agents (e.g., serotonin and thromboxane A2, leading to intense arteriolar vasopasm in the distal vasculature. In the animal laboratory, experimental no reflow has been shown to be due to the plugging of capillaries by red blood cells and neutrophils, myocyte contracture and local intracellular and interstitial edema.4,5      A loss of capillary autoregulation and severe microvascular dysfunction are the ultimate physiologic consequences of these microscopic anatomic alterations. Debris of varying sizes of particulate has variable effects on microcirculatory plugging. The effect of particle size on microvascular dysfunction has been mostly investigated during

  18. The crossed phrenic phenomenon.

    Science.gov (United States)

    Ghali, Michael George Zaki

    2017-06-01

    The cervical spine is the most common site of traumatic vertebral column injuries. Respiratory insufficiency constitutes a significant proportion of the morbidity burden and is the most common cause of mortality in these patients. In seeking to enhance our capacity to treat specifically the respiratory dysfunction following spinal cord injury, investigators have studied the "crossed phrenic phenomenon", wherein contraction of a hemidiaphragm paralyzed by a complete hemisection of the ipsilateral cervical spinal cord above the phrenic nucleus can be induced by respiratory stressors and recovers spontaneously over time. Strengthening of latent contralateral projections to the phrenic nucleus and sprouting of new descending axons have been proposed as mechanisms contributing to the observed recovery. We have recently demonstrated recovery of spontaneous crossed phrenic activity occurring over minutes to hours in C 1 -hemisected unanesthetized decerebrate rats. The specific neurochemical and molecular pathways underlying crossed phrenic activity following injury require further clarification. A thorough understanding of these is necessary in order to develop targeted therapies for respiratory neurorehabilitation following spinal trauma. Animal studies provide preliminary evidence for the utility of neuropharmacological manipulation of serotonergic and adenosinergic pathways, nerve grafts, olfactory ensheathing cells, intraspinal microstimulation and a possible role for dorsal rhizotomy in recovering phrenic activity following spinal cord injury.

  19. The phenomenon of retarded potentials

    International Nuclear Information System (INIS)

    Noskov, N.K.

    2003-01-01

    The logic simulation of process of time delay of potential on a moved body - recipient resulted in the deduction about cyclic irregularity of time delay, that means, that the moved body makes longitudinal vibrations. A conclusion is drawn that length of longitudinal vibrations depending from three variable: the law of interaction, spacing interval between bodies of interaction and phase velocity looks like: λ=Hv ph /R·F(R) (1), where λ- length of oscillations; H- factor of proportionality; v ph - phase velocity of a body; R - distance between test and central bodies R(t); F(R) - law of interaction. So far as λ=v ph /v, and R·F(R)=∫ ∞ R F(R)dR=E move , then formula (1) will be transformed into: E move =Hv pv /λ=Hv. Thus, the energy of radiating having the similar law is only reflex of motion of a matter. The energy of oscillating motion can be expressed through linear maximal velocity. It is established, that different expressions of the same energy, result in the law of a view of a proportion for lengths of de Broglie's waves: It shows that de Broglie's waves - the actual oscillating motions of bodies, as demonstrate interference and diffraction pictures at a dissipation of the accelerated particles on crystalline gratings. This deduction has far-reaching consequences for finding - out of the cause bases of the laws of a nature. So, the quantum mechanics becomes partition of mechanics of solids and is comprises all interactions. The nuclear energy is not 'defect of mass', but is 'defect' of energy of oscillating motion: ΔE=H v1 -H v2 . Definition of real cause of nuclear energy is very important for construction of model of nuclei and for development of physics as the whole. The interconnection of the phenomenon of longitudinal vibrations of moved bodies, as result of irregularity of time delay of potential, with many other natural phenomena is looked through. By such, as: motion of planets and electrons on elliptical orbits, oscillating of dipping drips

  20. Raynaud’s phenomenon

    Directory of Open Access Journals (Sweden)

    F. Ingegnoli

    2011-09-01

    Full Text Available Raynaud’s phenomenon (RP is a vasospastic disorder characterized by episodic color changes of blanching, cyanosis, and hyperemia in response to cold and/or emotional stress. Although most typically noted in the fingers, the circulation of the toes, ears, nose and tongue is also frequently affected. Population studies have shown that RP in adults is more common in women than men, with prevalence estimates ranging from 4% to 30%. Geographic variations in the prevalence reflect differences in climate. RP may be a primary or a secondary process. LeRoy and Medsger suggested criteria for primary RP: symmetric attacks, the absence of tissue necrosis, ulceration or gangrene, the absence of a secondary cause, negative antinuclear antibodies, normal nailfold capillaroscopy and a normal erythrocyte sedimentation rate. Secondary RP is characterized by an age of onset of more than 30 years, painful and asymmetric attacks, ischemic skin lesions, positive autoautoantibodies, capillaroscopic abnormalities and/or clinical features suggestive of connective tissue diseases (CTDs. Among the CTDs, systemic sclerosis has the highest frequency of RP. Finding a cause for RP requires a knowledge of the patient’s occupational, smoking, drug history, physical examination, nailfold capillaroscopy, routine laboratory tests and autoantibodies. Furthermore, RP should be distinguished from acrocyanosis, a condition characterized by continuous cyanosis of the hands or feet that is aggravated by cold temperature. The most important instruction to the patient is abstinence from any smoking, offending drugs should be discontinued, and abrupt changes in temperature. If these measures are inadequate, calcium-channel blockers are the most widely used (nifedipine 30 mg up to 90 mg daily. Alternatively, sympatholytic agent (prazosin, angiotensin II -receptor type I antagonist (losartan, selective sertonin-reuptake inhibitor (fluoxetine may be useful. In the severe cases the role of

  1. The tsunami phenomenon

    Science.gov (United States)

    Röbke, B. R.; Vött, A.

    2017-12-01

    With human activity increasingly concentrating on coasts, tsunamis (from Japanese tsu = harbour, nami = wave) are a major natural hazard to today's society. Stimulated by disastrous tsunami impacts in recent years, for instance in south-east Asia (2004) or in Japan (2011), tsunami science has significantly flourished, which has brought great advances in hazard assessment and mitigation plans. Based on tsunami research of the last decades, this paper provides a thorough treatise on the tsunami phenomenon from a geoscientific point of view. Starting with the wave features, tsunamis are introduced as long shallow water waves or wave trains crossing entire oceans without major energy loss. At the coast, tsunamis typically show wave shoaling, funnelling and resonance effects as well as a significant run-up and backflow. Tsunami waves are caused by a sudden displacement of the water column due to a number of various trigger mechanisms. Such are earthquakes as the main trigger, submarine and subaerial mass wastings, volcanic activity, atmospheric disturbances (meteotsunamis) and cosmic impacts, as is demonstrated by giving corresponding examples from the past. Tsunamis are known to have a significant sedimentary and geomorphological off- and onshore response. So-called tsunamites form allochthonous high-energy deposits that are left at the coast during tsunami landfall. Tsunami deposits show typical sedimentary features, as basal erosional unconformities, fining-upward and -landward, a high content of marine fossils, rip-up clasts from underlying units and mud caps, all reflecting the hydrodynamic processes during inundation. The on- and offshore behaviour of tsunamis and related sedimentary processes can be simulated using hydro- and morphodynamic numerical models. The paper provides an overview of the basic tsunami modelling techniques, including discretisation, guidelines for appropriate temporal and spatial resolution as well as the nesting method. Furthermore, the

  2. Optimization of fuel ethanol recovery systems using molecular sieves

    International Nuclear Information System (INIS)

    Scheller, W.A.

    1989-01-01

    The use of molecular sieves for the dehydration of rectified fuel ethanol requires only about 58% of the energy required by azeotropic distillation, the usual commercial process. Recently molecular sieve prices have become low enough that their use can be economically competitive with azeotropic distillation. This paper contains results of mass and energy balances to determine the water content of the rectified ethanol (6.15 weight percent) that will result in the minimum energy requirement for producing anhydrous ethanol with the molecular sieve process and byproduct distillers soluble syrup from fermented corn mash containing 7.23 weight percent ethanol. In this paper results of economic evaluations to determine the water content of the rectified ethanol (7.58 weight percent) which results in a minimum investment and operating cost are presented

  3. Super-resolving random-Gaussian apodized photon sieve.

    Science.gov (United States)

    Sabatyan, Arash; Roshaninejad, Parisa

    2012-09-10

    A novel apodized photon sieve is presented in which random dense Gaussian distribution is implemented to modulate the pinhole density in each zone. The random distribution in dense Gaussian distribution causes intrazone discontinuities. Also, the dense Gaussian distribution generates a substantial number of pinholes in order to form a large degree of overlap between the holes in a few innermost zones of the photon sieve; thereby, clear zones are formed. The role of the discontinuities on the focusing properties of the photon sieve is examined as well. Analysis shows that secondary maxima have evidently been suppressed, transmission has increased enormously, and the central maxima width is approximately unchanged in comparison to the dense Gaussian distribution. Theoretical results have been completely verified by experiment.

  4. The sieve element occlusion gene family in dicotyledonous plants.

    Science.gov (United States)

    Ernst, Antonia M; Rüping, Boris; Jekat, Stephan B; Nordzieke, Steffen; Reineke, Anna R; Müller, Boje; Bornberg-Bauer, Erich; Prüfer, Dirk; Noll, Gundula A

    2011-01-01

    Sieve element occlusion (SEO) genes encoding forisome subunits have been identified in Medicago truncatula and other legumes. Forisomes are structural phloem proteins uniquely found in Fabaceae sieve elements. They undergo a reversible conformational change after wounding, from a condensed to a dispersed state, thereby blocking sieve tube translocation and preventing the loss of photoassimilates. Recently, we identified SEO genes in several non-Fabaceae plants (lacking forisomes) and concluded that they most probably encode conventional non-forisome P-proteins. Molecular and phylogenetic analysis of the SEO gene family has identified domains that are characteristic for SEO proteins. Here, we extended our phylogenetic analysis by including additional SEO genes from several diverse species based on recently published genomic data. Our results strengthen the original assumption that SEO genes seem to be widespread in dicotyledonous angiosperms, and further underline the divergent evolution of SEO genes within the Fabaceae.

  5. Double rotation NMR studies of zeolites and aluminophosphate molecular sieves

    Energy Technology Data Exchange (ETDEWEB)

    Jelinek, Raz [Univ. of California, Berkeley, CA (United States)

    1993-07-01

    Goal is to study the organization and structures of guest atoms and molecules and their reactions on internal surfaces within pores of zeolites and aluminophosphate molecular sieves. 27Al and 23Na double rotation NMR (DOR) is used since it removes the anisotropic broadening in NMR spectra of quadrupolar nuclei, thus increasing resolution. This work concentrates on probing aluminum framework atoms in aluminophosphate molecular sieves and sodium extra framework cations in porous aluminosilicates. In aluminophosphates, ordering and electronic environments of the framework 27Al nuclei are modified upon adsorption of water molecules within the channels; a relation is sought between the sieve channel topology and the organization of adsorbed water, as well as the interaction between the Al nuclei and the water molecules. Extra framework Na+ cations are directly involved in adsorption processes and reactions in zeolite cavities.

  6. The feasibility of images reconstructed with the method of sieves

    International Nuclear Information System (INIS)

    Veklerov, E.; Llacer, J.

    1990-01-01

    The concept of sieves has been applied with the maximum likelihood estimator (MLE) to image reconstruction. While it makes it possible to recover smooth images consistent with the data, the degree of smoothness provided by it is arbitrary. It is shown that the concept of feasibility is able to resolve this arbitrariness. By varying the values of parameters determining the degree of smoothness, one can generate images on both sides of the feasibility region, as well as within the region. Feasible images recovered by using different sieve parameters are compared with feasible results of other procedures. One- and two-dimensional examples using both simulated and real data sets are considered

  7. POROUS ALUMINOPHOSPHATES :From Molecular Sieves to Designed Acid Catalysts

    Science.gov (United States)

    Pastore, H. O.; Coluccia, S.; Marchese, L.

    2005-08-01

    This review covers the synthesis, characterization, and physico-chemical properties of microporous and mesoporous aluminophosphates and silicoaluminophosphates molecular sieves. Particular emphasis is given to the materials that have found applications as acid catalysts. We consider the evolution of the synthesis procedures from the first discoveries to the current methodologies and give perspectives for new possible synthesis strategies. Emphasis is given to the use of specially prepared precursors/reactants designed for the use as molecular sieves. Experimental (especially MAS-NMR and FTIR spectroscopy) and theoretical approaches to the description of the Si insertion into the ALPO framework and to the acidic properties of SAPOs and MeAPSOs materials are discussed.

  8. HOOLIGANISM – CONTEMPORARY SOCIAL PHENOMENON

    Directory of Open Access Journals (Sweden)

    MARIA LULESCU

    2012-05-01

    Full Text Available The proposed scientific theme is going to approach and study the hooliganism phenomenon as a contemporary social matter, in terms of conceptual and etiological. The present work has four main purposes: (1- that of explaining the meaning of hooliganism social phenomenon; (2- that of discovering the origins of hooliganism; (3- that of knowing which are the causes that encourages the occurence of the hooliganism; (4- that of knowing how to control and minimize this phenomenon.

  9. Cyclic nucleotides and radioresistnace

    International Nuclear Information System (INIS)

    Kulinskij, V.I.; Mikheeva, G.A.; Zel'manovich, B.M.

    1982-01-01

    The addition of glucose to meat-peptone broth does not change the radiosensitizing effect (RSE) of cAMP at the logarithmic phase (LP) and the radioprotective effect (RPE) at the stationary phase (SP), but sensitization, characteristic of cGMP, disappears in SP and turns into RPE in LP. Introduction of glucose into the broth for 20 min eliminates all the effects of both cyclic nucleotides in the cya + strain while cya - mutant exhibits RSE. RSE of both cyclic nucleotides is only manifested on minimal media. These data brought confirmation of the dependence of the influence of cyclic media. These data brought confirmation of the dependence of the influence of cyclic nucleotides on radioresistance upon the metabolic status of the cell [ru

  10. Adsorption properties of the SAPO-5 molecular sieve

    KAUST Repository

    Hu, Enping; Lai, Zhiping; Wang, Kean

    2010-01-01

    The adsorption properties of an aluminophosphate molecular sieve, SAPO-5, were measured for a number of gases and vapors, including N2, water, isopropanol, and xylenes. The data showed that SAPO-5 is quite hydrophobic and has a strong selectivity of o-xylene over its isomers m- and p-xylene. © 2010 American Chemical Society.

  11. High-Flux Carbon Molecular Sieve Membranes for Gas Separation.

    Science.gov (United States)

    Richter, Hannes; Voss, Hartwig; Kaltenborn, Nadine; Kämnitz, Susanne; Wollbrink, Alexander; Feldhoff, Armin; Caro, Jürgen; Roitsch, Stefan; Voigt, Ingolf

    2017-06-26

    Carbon membranes have great potential for highly selective and cost-efficient gas separation. Carbon is chemically stable and it is relative cheap. The controlled carbonization of a polymer coating on a porous ceramic support provides a 3D carbon material with molecular sieving permeation performance. The carbonization of the polymer blend gives turbostratic carbon domains of randomly stacked together sp 2 hybridized carbon sheets as well as sp 3 hybridized amorphous carbon. In the evaluation of the carbon molecular sieve membrane, hydrogen could be separated from propane with a selectivity of 10 000 with a hydrogen permeance of 5 m 3 (STP)/(m 2 hbar). Furthermore, by a post-synthesis oxidative treatment, the permeation fluxes are increased by widening the pores, and the molecular sieve carbon membrane is transformed from a molecular sieve carbon into a selective surface flow carbon membrane with adsorption controlled performance and becomes selective for carbon dioxide. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Journal of EEA, Vol. 30, 2013 SIEVE TRAY EFFICIENCY USING ...

    African Journals Online (AJOL)

    dell

    Journal of EEA, Vol. 30, 2013. SIEVE TRAY EFFICIENCY USING CFD MODELING AND SIMULATION ... ABSTRACT. In this work, computational fluid dynamics (CFD) .... per unit volume, MG is the molecular weight of the gas/vapor, kL and kG ...

  13. Mesoporous molecular sieves as advanced supports for olefin metathesis catalysts

    Czech Academy of Sciences Publication Activity Database

    Balcar, Hynek; Čejka, Jiří

    2013-01-01

    Roč. 257, 21-22 (2013), s. 3107-3124 ISSN 0010-8545 R&D Projects: GA AV ČR IAA400400805; GA ČR GBP106/12/G015 Institutional support: RVO:61388955 Keywords : Olefin metathesis * mesoporous molecular sieves * Heterogeneous catalysts Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 12.098, year: 2013

  14. Effect of processing on carbon molecular sieve structure and performance

    KAUST Repository

    Das, Mita; Perry, John D.; Koros, William J.

    2010-01-01

    Sub-micron sized carbon molecular sieve (CMS) materials were produced via ball milling for subsequent use in hybrid material formation. A detailed analysis of the effects of the milling process in the presence of different milling environments is reported. The milling process apparently alters the molecular scale structure and properties of the carbon material. Three cases: unmilled, air milled and nitrogen milled, were analyzed in this work. The property changes were probed using equilibrium sorption experiments with different gases. Furthermore, WAXD and BET results also showed differences between milling processes. Finally in order to improve the interfacial polymer-sieve region of hybrid membranes, the CMS surface was chemically modified with a linkage unit capable of covalently bonding the polymer to the sieve. A published single-wall carbon nanotube (SWCNTs) modification method was adopted to attach a primary aromatic amine to the surface. Several aspects including rigidity, chemical composition, bulky groups and length were considered in selecting the preferred linkage unit. Fortunately kinetic and equilibrium sorption properties of the modified sieves showed very little difference from unmodified samples, suggesting that the linkage unit is not excessively filling or obstructing access to the pores of the CMSs during the modification process. © 2010 Elsevier Ltd. All rights reserved.

  15. Tunable sieving of ions using graphene oxide membranes

    Science.gov (United States)

    Abraham, Jijo; Vasu, Kalangi S.; Williams, Christopher D.; Gopinadhan, Kalon; Su, Yang; Cherian, Christie T.; Dix, James; Prestat, Eric; Haigh, Sarah J.; Grigorieva, Irina V.; Carbone, Paola; Geim, Andre K.; Nair, Rahul R.

    2017-07-01

    Graphene oxide membranes show exceptional molecular permeation properties, with promise for many applications. However, their use in ion sieving and desalination technologies is limited by a permeation cutoff of ˜9 Å (ref. 4), which is larger than the diameters of hydrated ions of common salts. The cutoff is determined by the interlayer spacing (d) of ˜13.5 Å, typical for graphene oxide laminates that swell in water. Achieving smaller d for the laminates immersed in water has proved to be a challenge. Here, we describe how to control d by physical confinement and achieve accurate and tunable ion sieving. Membranes with d from ˜9.8 Å to 6.4 Å are demonstrated, providing a sieve size smaller than the diameters of hydrated ions. In this regime, ion permeation is found to be thermally activated with energy barriers of ˜10-100 kJ mol-1 depending on d. Importantly, permeation rates decrease exponentially with decreasing sieve size but water transport is weakly affected (by a factor of <2). The latter is attributed to a low barrier for the entry of water molecules and large slip lengths inside graphene capillaries. Building on these findings, we demonstrate a simple scalable method to obtain graphene-based membranes with limited swelling, which exhibit 97% rejection for NaCl.

  16. Factorization of RSA-140 using the number field sieve

    NARCIS (Netherlands)

    S.H. Cavallar; B. Dodson; A.K. Lenstra (Arjen); P.C. Leyland; W.M. Lioen (Walter); P.L. Montgomery; B. Murphy; H.J.J. te Riele (Herman); P. Zimmermann

    1999-01-01

    textabstractOn February 2, 1999, we completed the factorization of the 140--digit number RSA--140 with the help of the Number Field Sieve factoring method (NFS). This is a new general factoring record. The previous record was established on April 10, 1996 by the factorization of the 130--digit

  17. Strategies in filtering in the number field sieve

    NARCIS (Netherlands)

    S.H. Cavallar

    2000-01-01

    textabstractA critical step when factoring large integers by the Number Field Sieve consists of finding dependencies in a huge sparse matrix over the field GF(2), using a Block Lanczos algorithm. Both size and weight (the number of non-zero elements) of the matrix critically affect the running time

  18. Carbon molecular sieve membranes prepared from porous fiber precursor

    NARCIS (Netherlands)

    Barsema, J.N.; van der Vegt, N.F.A.; Koops, G.H.; Wessling, Matthias

    2002-01-01

    Carbon molecular sieve (CMS) membranes are usually prepared from dense polymeric precursors that already show intrinsic gas separation properties. The rationale behind this approach is that the occurrence of any kind of initial porosity will deteriorate the final CMS performance. We will show that

  19. On polynomial selection for the general number field sieve

    Science.gov (United States)

    Kleinjung, Thorsten

    2006-12-01

    The general number field sieve (GNFS) is the asymptotically fastest algorithm for factoring large integers. Its runtime depends on a good choice of a polynomial pair. In this article we present an improvement of the polynomial selection method of Montgomery and Murphy which has been used in recent GNFS records.

  20. Some aspects on the conditioning of the molecular sieves waste

    International Nuclear Information System (INIS)

    Deneanu, N.; Dulama, M.; Teoreanu, I.

    2009-01-01

    The paper deals with a systematic approach of some important problems, concerning the conditioning of the molecular sieves wastes resulted from Cernavoda Nuclear Power Plant using binder materials, ensuring the prerequisites for elaboration of the recipes of the waste forms. In order to justify the more or less different behavior of wide range of potential binder materials (high alumina cement, Type II Portland blast furnace cement, Type I normal Portland cement) in relation to the molecular sieves content, within the paper there were studied the leach rates of tritium and the compressive strengths. Moreover, the research work took into consideration the correlations between composition-processing-proprieties, mixing properties (workability) and hardening process (setting time). Typical properties and limits of the molecular sieves waste forms could meet the Waste Acceptance Criteria of the disposal site. The experimental results suggest that, the normal Portland cement is the best binder material for immobilizing molecular sieves wastes while addition of sand and dispersed agent into matrices would greatly enhance the properties of the waste forms. (authors)

  1. Adsorption properties of the SAPO-5 molecular sieve

    KAUST Repository

    Hu, Enping

    2010-09-09

    The adsorption properties of an aluminophosphate molecular sieve, SAPO-5, were measured for a number of gases and vapors, including N2, water, isopropanol, and xylenes. The data showed that SAPO-5 is quite hydrophobic and has a strong selectivity of o-xylene over its isomers m- and p-xylene. © 2010 American Chemical Society.

  2. Effect of processing on carbon molecular sieve structure and performance

    KAUST Repository

    Das, Mita

    2010-11-01

    Sub-micron sized carbon molecular sieve (CMS) materials were produced via ball milling for subsequent use in hybrid material formation. A detailed analysis of the effects of the milling process in the presence of different milling environments is reported. The milling process apparently alters the molecular scale structure and properties of the carbon material. Three cases: unmilled, air milled and nitrogen milled, were analyzed in this work. The property changes were probed using equilibrium sorption experiments with different gases. Furthermore, WAXD and BET results also showed differences between milling processes. Finally in order to improve the interfacial polymer-sieve region of hybrid membranes, the CMS surface was chemically modified with a linkage unit capable of covalently bonding the polymer to the sieve. A published single-wall carbon nanotube (SWCNTs) modification method was adopted to attach a primary aromatic amine to the surface. Several aspects including rigidity, chemical composition, bulky groups and length were considered in selecting the preferred linkage unit. Fortunately kinetic and equilibrium sorption properties of the modified sieves showed very little difference from unmodified samples, suggesting that the linkage unit is not excessively filling or obstructing access to the pores of the CMSs during the modification process. © 2010 Elsevier Ltd. All rights reserved.

  3. Ca2+-mediated remote control of reversible sieve tube occlusion in em>Vicia faba em>

    DEFF Research Database (Denmark)

    Furch, Alexandra C.U.; Hafke, Jens B.; Schulz, Alexander

    2007-01-01

    According to an established concept, injury of the phloem triggers local sieve plate occlusion including callose-mediated constriction and, possibly, protein plugging of the sieve pores. Sieve plate occlusion can also be achieved by distant stimuli, depends on the passage of electropotential waves...

  4. THE ROMANIAN MIGRATIONAL EVOLUTION PHENOMENON

    Directory of Open Access Journals (Sweden)

    Cristian Raluca

    2009-05-01

    Full Text Available In our contemporary democratic society the migration phenomenon meets unknown valences in any previous societies. Free will and right to self-determination, much exploited by the XX century society., raised the possibility of interpretation of migration

  5. Generalized Wideband Cyclic MUSIC

    Directory of Open Access Journals (Sweden)

    Zhang-Meng Liu

    2009-01-01

    Full Text Available The method of Spectral Correlation-Signal Subspace Fitting (SC-SSF fails to separate wideband cyclostationary signals with coherent second-order cyclic statistics (SOCS. Averaged Cyclic MUSIC (ACM method made up for the drawback to some degree via temporally averaging the cyclic cross-correlation of the array output. This paper interprets ACM from another perspective and proposes a new DOA estimation method by generalizing ACM for wideband cyclostationary signals. The proposed method successfully makes up for the aforementioned drawback of SC-SSF and obtains a more satisfying performance than ACM. It is also demonstrated that ACM is a simplified form of the proposed method when only a single spectral frequency is exploited, and the integration of the frequencies within the signal bandwidth helps the new method to outperform ACM.

  6. Modified molecular sieves: stationary phase for the gas chromatographic separation of hydrogen isotopes

    International Nuclear Information System (INIS)

    Pushpa, K.K.; Annaji Rao, K.; Iyer, R.M.

    1993-01-01

    Gas chromatographic separation of hydrogen isotopes on different molecular sieves at liquid nitrogen temperature has been investigated. Normal molecular sieves 5A, 13X and AW500 are not satisfactory for the purpose both in the partially dehydrated as well as totally dehydrated state. Molecular sieve 4A in partially dehydrated state separated H 2 and D 2 while H 2 and HD are not well resolved. Iron exchanged or coated molecular sieves 4A, 5A, 13X and AW500 in the partially dehydrated state separated the isotopic mixtures H 2 , HD, D 2 and H 2 , HT, T 2 . The resolution varied depending on the amount of iron content and the residual moisture in the molecular sieves. Good separations were obtained on 15% Fe coated molecular sieve 5A and 5% Fe coated molecular sieve 4A. (author). 18 refs., 6 figs., 3 tabs

  7. Preventing gastric sieving by blending a solid/water meal enhances satiation in healthy humans.

    Science.gov (United States)

    Marciani, Luca; Hall, Nicholas; Pritchard, Susan E; Cox, Eleanor F; Totman, John J; Lad, Mita; Hoad, Caroline L; Foster, Tim J; Gowland, Penny A; Spiller, Robin C

    2012-07-01

    Separation of solids and liquids within the stomach allows faster gastric emptying of liquids compared with solids, a phenomenon known as sieving. We tested the hypothesis that blending a solid and water meal would abolish sieving, preventing the early rapid decrease in gastric volume and thereby enhancing satiety. We carried out 2 separate studies. Study 1 was a 2-way, crossover, satiety study of 22 healthy volunteers who consumed roasted chicken and vegetables with a glass of water (1008 kJ) or the same blended to a soup. They completed satiety visual analogue scales at intervals for 3 h. Study 2 was a 2-way, crossover, mechanistic study of 18 volunteers who consumed the same meals and underwent an MRI to assess gastric emptying, gallbladder contraction, and small bowel water content (SBWC) at intervals for 3 h. In Study 1, the soup meal was associated with reduced hunger (P = 0.02). In Study 2, the volume of the gastric contents after the soup meal decreased more slowly than after the solid/liquid meal (P = 0.0003). The soup meal caused greater gallbladder contraction (P < 0.04). SBWC showed a biphasic response with an initial "gastric" phase during which SBWC was greater when the solid/liquid meal was consumed (P < 0.001) and a later "small bowel" phase when SBWC was greater when the soup meal was consumed (P < 0.01). Blending the solid/liquid meal to a soup delayed gastric emptying and increased the hormonal response to feeding, which may contribute to enhanced postprandial satiety.

  8. Oxygen and nitrogen diffusion in coal-molecular sieve

    International Nuclear Information System (INIS)

    Stefanescu, Doina Maria

    1996-01-01

    Recently, the air separation process based on selective adsorption of carbon-molecular sieves has been developed strongly. The separation is based on the system kinematics and depends on the oxygen diffusion in adsorber micropores. The oxygen is preferentially adsorbed and in given conditions it is possible to obtain nitrogen of high purity. Recent theoretical and experimental studies concerning the production of nitrogen by PSA process have shown that the obtained performances can not be described by a constant diffusion model. The paper present the 'dual' model assumed for O 2 and N 2 diffusion through molecular sieve as well as the experimental data obtained in the adsorption study on carbon material produced at ICIS to determine the diffusivity values in micropores

  9. Quadratic grating apodized photon sieves for simultaneous multiplane microscopy

    Science.gov (United States)

    Cheng, Yiguang; Zhu, Jiangping; He, Yu; Tang, Yan; Hu, Song; Zhao, Lixin

    2017-10-01

    We present a new type of imaging device, named quadratic grating apodized photon sieve (QGPS), used as the objective for simultaneous multiplane imaging in X-rays. The proposed QGPS is structured based on the combination of two concepts: photon sieves and quadratic gratings. Its design principles are also expounded in detail. Analysis of imaging properties of QGPS in terms of point-spread function shows that QGPS can image multiple layers within an object field onto a single image plane. Simulated and experimental results in visible light both demonstrate the feasibility of QGPS for simultaneous multiplane imaging, which is extremely promising to detect dynamic specimens by X-ray microscopy in the physical and life sciences.

  10. Cyclic deformation of NiTi shape memory alloys

    International Nuclear Information System (INIS)

    Liu Yong; Van Humbeeck, J.; Xie Zeliang

    1999-01-01

    Recently, there is an increasing interest in applying the high damping capacity of shape memory alloys (SMAs). The purpose is to explore the feasibility of those materials for the protection of buildings and other civil constructions as a result of earthquake damages. So far, few experimental results have been reported concerning the mechanical cyclic behaviour of SMAs in their martensitic state (ferroelastic). In the present work, the experimental results on the mechanical behaviour of martensitic NiTi SMAs under tension-compression cyclic deformation up to strains of ±4% are summarized with major attention to the damping capacity, characteristic stresses and strains as a function of deformation cycles. Effect of strain rate, strain amplitude and annealing condition on the martensite damping is summarized. Explanation of the cyclic hardening and cyclic softening phenomenon is proposed based on TEM observations. (orig.)

  11. Adsorption methods for hydrogen isotope storage on zeolitic sieves

    International Nuclear Information System (INIS)

    Cristescu, Ioana; Cristescu, Ion; Vasut, F.; Brad, S.; Lazar, A.

    2001-01-01

    For hydrogen isotope separation, adsorption molecular sieves and active carbon were used. Adsorption process proceeds at liquid nitrogen and liquid hydrogen temperatures. Commercial zeolites have the same proprieties with natural zeolites, but they have a regular pore structure. They also have affinity for molecules of different size with defined shapes. Experimental results obtained at liquid nitrogen temperature (77.4 K) and liquid hydrogen revealed the efficient behaviour of the active carbon and zeolitic sieves for hydrogen isotopes temporary storage. We study adsorption of the synthetic zeolites in a wide range of temperatures and pressures and we used the molecular sieves 4A, 5A and active carbon. The 4A and 5A zeolites have a tridimensional structure with 11.4 A diameter. When the hydration water is eliminated, the material keeps a porous structure. The porous volume represents 45% from the zeolite mass for 4A and 5A sieves. The activation temperature of the zeolite and the carbon is very important for obtaining a high adsorption capacity. If the temperature used for activation is low, the structural water will be not eliminated and the adsorption capacity will be low. The excessive temperature will destroy the porous structure. The adsorption capacity for the hydrogen isotopes was calculated with the relation: A = V ads /m (cm 3 /g). The adsorption capacity and efficiency for the adsorbent materials, are given. Physical adsorption process of the hydrogen isotopes was carried out at liquid nitrogen temperature. The flux gas used in the adsorption system is composed of dry deuterium and protium. This mixture is cooled in liquid nitrogen and then is passed to the adsorbent getter at the same temperature (77.4 K). The gas flux in the adsorbent getter is 5 and 72 l/h (which correspond to 0.008 and 0.134 discharge velocity, respectively). (authors)

  12. A differential delay equation arising from the sieve of Eratosthenes

    Science.gov (United States)

    Cheer, A. Y.; Goldston, D. A.

    1990-01-01

    Consideration is given to the differential delay equation introduced by Buchstab (1937) in connection with an asymptotic formula for the uncanceled terms in the sieve of Eratosthenes. Maier (1985) used this result to show there is unexpected irreqularity in the distribution of primes in short intervals. The function omega(u) is studied in this paper using numerical and analytical techniques. The results are applied to give some numerical constants in Maier's theorem.

  13. Recent Advances in Catalysis Over Mesoporous Molecular Sieves

    Czech Academy of Sciences Publication Activity Database

    Martín-Aranda, R. M.; Čejka, Jiří

    2010-01-01

    Roč. 53, 3-4 (2010), s. 141-153 ISSN 1022-5528 R&D Projects: GA AV ČR KAN100400701; GA AV ČR IAA400400805; GA ČR GA104/09/0561 Institutional research plan: CEZ:AV0Z40400503 Keywords : mesoporous molecular sieves * MCM-41 * SBA-15 * mesoporous alumina Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.359, year: 2010

  14. Polynomial selection in number field sieve for integer factorization

    Directory of Open Access Journals (Sweden)

    Gireesh Pandey

    2016-09-01

    Full Text Available The general number field sieve (GNFS is the fastest algorithm for factoring large composite integers which is made up by two prime numbers. Polynomial selection is an important step of GNFS. The asymptotic runtime depends on choice of good polynomial pairs. In this paper, we present polynomial selection algorithm that will be modelled with size and root properties. The correlations between polynomial coefficient and number of relations have been explored with experimental findings.

  15. A parallel line sieve for the GNFS Algorithm

    OpenAIRE

    Sameh Daoud; Ibrahim Gad

    2014-01-01

    RSA is one of the most important public key cryptosystems for information security. The security of RSA depends on Integer factorization problem, it relies on the difficulty of factoring large integers. Much research has gone into problem of factoring a large number. Due to advances in factoring algorithms and advances in computing hardware the size of the number that can be factorized increases exponentially year by year. The General Number Field Sieve algorithm (GNFS) is currently the best ...

  16. MXene molecular sieving membranes for highly efficient gas separation.

    Science.gov (United States)

    Ding, Li; Wei, Yanying; Li, Libo; Zhang, Tao; Wang, Haihui; Xue, Jian; Ding, Liang-Xin; Wang, Suqing; Caro, Jürgen; Gogotsi, Yury

    2018-01-11

    Molecular sieving membranes with sufficient and uniform nanochannels that break the permeability-selectivity trade-off are desirable for energy-efficient gas separation, and the arising two-dimensional (2D) materials provide new routes for membrane development. However, for 2D lamellar membranes, disordered interlayer nanochannels for mass transport are usually formed between randomly stacked neighboring nanosheets, which is obstructive for highly efficient separation. Therefore, manufacturing lamellar membranes with highly ordered nanochannel structures for fast and precise molecular sieving is still challenging. Here, we report on lamellar stacked MXene membranes with aligned and regular subnanometer channels, taking advantage of the abundant surface-terminating groups on the MXene nanosheets, which exhibit excellent gas separation performance with H 2 permeability >2200 Barrer and H 2 /CO 2 selectivity >160, superior to the state-of-the-art membranes. The results of molecular dynamics simulations quantitatively support the experiments, confirming the subnanometer interlayer spacing between the neighboring MXene nanosheets as molecular sieving channels for gas separation.

  17. Radiation effects on methane in the presence of molecular sieves

    International Nuclear Information System (INIS)

    Shimizu, Y.; Nagai, S.; Hatada, M.

    1983-01-01

    Product analysis has been carried out for the radiation-induced reaction of methane in the presence of molecular sieves (MS) 3A, 4A, 5A and 13X. Irradiation of methane over MS 4A selectively produces C 2 hydrocarbons, while the use of MS 5A leads to C 2 and C 3 hydrocarbons. The selectivity and yields of these hydrocarbons, however, decrease with irradiation time, owing to deposition of carbonaceous solid produced from methane on the surface of the molecular sieves. The carbonaceous solid is decomposed to low-molecular-weight hydrocarbons when irradiated in an H 2 atmosphere. Material balance estimated for the radiation-chemical reaction of argon containing 2 mol% methane over MS 5A reveals that the carbonaceous solid is highly abundant in carbon atoms. On the other hand the formation of carbonaceous solids plays a less important role in the radiation-chemical reaction of methane in the presence of silica gel, which is found to exhibit greater activity for the formation of hydrocarbons than the molecular sieves. (author)

  18. Unexpected Molecular Sieving Properties of Zeolitic Imidazolate Framework-8

    KAUST Repository

    Zhang, Chen

    2012-08-16

    We studied molecular sieving properties of zeolitic imidazolate framework-8 (ZIF-8) by estimating the thermodynamically corrected diffusivities of probe molecules at 35 °C. From helium (2.6 Å) to iso-C 4H 10 (5.0 Å), the corrected diffusivity drops 14 orders of magnitude. Our results further suggest that the effective aperture size of ZIF-8 for molecular sieving is in the range of 4.0 to 4.2 Å, which is significantly larger than the XRD-derived value (3.4 Å) and between the well-known aperture size of zeolite 4A (3.8 Å) and 5A (4.3 Å). Interestingly, because of aperture flexibility, the studied C 4 hydrocarbon molecules that are larger than this effective aperture size still adsorb in the micropores of ZIF-8 with kinetic selectivities for iso-C 4H 8/iso-C 4H 10 of 180 and n-C 4H 10/iso-C 4H 10 of 2.5 × 10 6. These unexpected molecular sieving properties open up new opportunities for ZIF materials for separations that cannot be economically achieved by traditional microporous adsorbents such as synthetic zeolites. © 2012 American Chemical Society.

  19. Unexpected Molecular Sieving Properties of Zeolitic Imidazolate Framework-8

    KAUST Repository

    Zhang, Chen; Lively, Ryan P.; Zhang, Ke; Johnson, Justin R.; Karvan, Oguz; Koros, William J.

    2012-01-01

    We studied molecular sieving properties of zeolitic imidazolate framework-8 (ZIF-8) by estimating the thermodynamically corrected diffusivities of probe molecules at 35 °C. From helium (2.6 Å) to iso-C 4H 10 (5.0 Å), the corrected diffusivity drops 14 orders of magnitude. Our results further suggest that the effective aperture size of ZIF-8 for molecular sieving is in the range of 4.0 to 4.2 Å, which is significantly larger than the XRD-derived value (3.4 Å) and between the well-known aperture size of zeolite 4A (3.8 Å) and 5A (4.3 Å). Interestingly, because of aperture flexibility, the studied C 4 hydrocarbon molecules that are larger than this effective aperture size still adsorb in the micropores of ZIF-8 with kinetic selectivities for iso-C 4H 8/iso-C 4H 10 of 180 and n-C 4H 10/iso-C 4H 10 of 2.5 × 10 6. These unexpected molecular sieving properties open up new opportunities for ZIF materials for separations that cannot be economically achieved by traditional microporous adsorbents such as synthetic zeolites. © 2012 American Chemical Society.

  20. Competitive adsorption behaviors of carbon dioxide and n-dodecane mixtures in 13X molecular sieve

    Science.gov (United States)

    Zhu, Chaofan; Dong, Mingzhe; Gong, Houjian

    2018-01-01

    The CO2 cyclic injection has been proven to be effective to enhance tight oil recovery under constant reservoir temperature and down hole pressure conditions. However, the enhance tight oil recovery mechanism was unclear, especially the adsorption of the CO2 and alkane in the surface. Therefore, it is great important to study the adsorption mechanism of CO2 and alkane mixtures in tight oil. In this study, a new experimental method and apparatus have been designed to test the change of the mole fraction of CO2 and n-C12 before and after the adsorption equilibrium. Then, the adsorption amount of CO2 and n-C12 was obtained by a mathematical method. Moreover, the adsorption character of CO2 and n-C12 mixtures in 13X molecular sieve and the effect of pressure on the adsorption and amount were studied. The results show that the adsorption of CO2 and the desorption of n-C12 follow the Langmuir adsorption. This study provides a straightforward method to experimentally determine the adsorption properties of the tight oil, which can be used to evaluate enhanced tight oil recovery by CO2 injection.

  1. Koebner Phenomenon and Mycosis Fungoides

    Directory of Open Access Journals (Sweden)

    Eve Lebas

    2015-10-01

    Full Text Available Mycosis fungoides (MF is the most frequent type of primary cutaneous T-cell/NK-cell lymphoma. The Koebner phenomenon is defined as the appearance of cutaneous lesions on previously noninvolved skin following trauma and is observed in a series of cutaneous diseases including psoriasis, lichen planus, viral warts, molluscum contagiosum, etc. In this case report, 3 patients with longstanding MF are presented, the 1st with the appearance of a circumscribed early-stage type MF lesion rapidly following a surgical excision of an infundibular cyst, the 2nd with the appearance of a unique unilateral palmar tumoral MF lesion at the pressure site of a crutch, and the 3rd presented localized MF early stage lesions at the friction site of a belt. This report suggests that some MF patients may experience Koebner phenomenon-induced MF lesions and that MF should be added to the long list of skin diseases potentially exhibiting the Koebner phenomenon.

  2. The arabidopsis cyclic nucleotide interactome

    KAUST Repository

    Donaldson, Lara Elizabeth; Meier, Stuart Kurt; Gehring, Christoph A

    2016-01-01

    Cyclic nucleotides have been shown to play important signaling roles in many physiological processes in plants including photosynthesis and defence. Despite this, little is known about cyclic nucleotide-dependent signaling mechanisms

  3. Production of carbon molecular sieves from Illinois coal

    Science.gov (United States)

    Lizzio, A.A.; Rostam-Abadi, M.

    1993-01-01

    Carbon molecular sieves (CMS) have become an increasingly important class of adsorbents for application in the separation of gas molecules that vary in size and shape. A study is in progress at the Illinois State Geological Survey to determine whether Illinois basin coals are suitable feedstocks for the production of CMS and to evaluate their potential application in gas separation processes of commercial importance. Chars were prepared from Illinois coal in a fixed-bed reactor under a wide range of heat treatment and activation conditions. The effects of various coal/char pretreatments, including coal demineralization, preoxidation, char activation, and carbon deposition, on the molecular sieve properties of the chars were also investigated. Chars with commercially significant BET surface areas of 1500 m2/g were produced by chemical activation using potassium hydroxide as the activant. These high-surface-area (HSA) chars had more than twice the adsorption capacity of commercial carbon and zeolite molecular sieves. The kinetics of adsorption of various gases, e.g., N2, O2, CO2, CH4, CO and H2, on these chars at 25??C was measured. The O2/N2 molecular sieve properties of one char prepared without chemical activation were similar to those of a commercial CMS. On the other hand, the O2/N2 selectivity of the HSA char was comparable to that of a commercial activated carbon, i.e., essentially unity. Carbon deposition, using methane as the cracking gas, increased the O2/N2 selectivity of the HSA char, but significantly decreased its adsorption capacity. Several chars showed good potential for efficient CO2/CH4 separation; both a relatively high CO2 adsorption capacity and CO2/CH4 selectivity were achieved. The micropore size distribution of selected chars was estimated by equilibrium adsorption of carbon dioxide, n-butane and iso-butane at O??C. The extent of adsorption of each gas corresponded to the effective surface area contained in pores with diameters greater than 3

  4. Cyclic Voltammograms from First Principles

    DEFF Research Database (Denmark)

    Karlberg, Gustav; Jaramillo, Thomas; Skulason, Egill

    2007-01-01

    Cyclic voltammetry is a fundamental experimental tool for characterizing electrochemical surfaces. Whereas cyclic voltammetry is widely used within the field of electrochemistry, a way to quantitatively and directly relate the cyclic voltammogram to ab initio calculations has been lacking, even f...

  5. SCOPING STUDIES TO DEVELOP A METHOD TO DETERMINE PARTICLE SIZE IN SIMULANT SLUDGE SLURRIES BY SIEVING

    International Nuclear Information System (INIS)

    DAMON, CLICK

    2005-01-01

    A physical separation method (i.e. sieving) was investigated to determine particle size distribution in non-radioactive sludge slurry simulants with the goal of implementation into the SRNL (Savannah River National Laboratory) shielded cells for use with radioactive sludge slurries. The investigation included obtaining the necessary experimental equipment, developing accessory equipment for use with the sieve shaker (to be able to sieve simulant slurries with aqueous solutions), sieving three different simulant slurries through a number of sieves and determining the particle size distribution gravimetrically, and developing a sufficient cleaning protocol of the sieves for re-use. The experimental protocol involved successive sieving of a NIST standard (to check the particle size retention of the sieves) and three non-radioactive slurry simulants (Batch 3 Tank 40 Test 3, Tank 40 Drum 3 and CETL Sludge Batch 2, which had been previously characterized by Microtrac analysis) through smaller and smaller sieves (150 microns x 5 microns) via use of the wet sieving system or by hand. For each of the three slurries, duplicate experiments were carried out using filtered supernate and DI water (to check the accuracy of the method versus Microtrac data) to sieve the slurry. Particle size determinations using the wet sieving system with DI water agree well with Microtrac data on a volume basis and in some cases the sieving data may be more accurate particularly if the material sieved had large particles. A correction factor had to be applied to data obtained from experiments done with supernate due to the dissolved solids which dried upon the sieves in the drying stage of the experiments. Upon subtraction of the correction factors, the experimental results were very similar to those obtained with DI water. It should be noted that approximately 250 mL of each of three simulant slurries was necessary to have enough filtered supernate available to carry out the experiments. The

  6. HOST liner cyclic facilities

    Science.gov (United States)

    Schultz, D.

    1983-01-01

    The HOST Liner Cyclic Program is utilizing two types of test apparatus, rectangular box rigs and a full annular rig. To date two quartz lamp cyclic box rigs have been tested and a third is to begin testing in late October 1983. The box rigs are used to evaluate 5x8 inch rectangular linear samples. A 21 inch diameter outer liner simulator is also being built up for testing beginning in April 1984. All rigs are atmospheric rigs. The first box rig, a three 6-kVA lamp installation, was operated under adverse conditions to determine feasibility of using quartz lamps for cyclic testing. This work was done in December 1981 and looked promising. The second box rig, again using three 6-kVA lamps, was operated to obtain instrumentation durability information and initial data input to a Finite Element Model. This limited test program was conducted in August 1983. Five test plates were run. Instrumentation consisted of strain gages, thermocouples and thermal paint. The strain gages were found to fail at 1200 F as expected though plates were heated to 1700 F. The third box rig, containing four 6-kVA lamps, is in build up for testing to begin in late October 1983. In addition to 33 percent greater power input, this rig has provision for 400 F backside line cooling air and a viewing port suitable for IR camera viewing. The casing is also water cooled for extended durability.

  7. Photon Sieve Bandwidth Broadening by Reduction of Chromatic Aberration Effects Using Second-Stage Diffractive Optics

    Science.gov (United States)

    2015-03-26

    to copyright protection in the United States. AFIT-ENP-MS-15-M-086 PHOTON SIEVE BANDWIDTH BROADENING BY REDUCTION OF CHROMATIC ABERRATION...RELEASE; DISTRIBUTION UNLIMITED. AFIT-ENP-MS-15-M-086 PHOTON SIEVE BANDWIDTH BROADENING BY REDUCTION OF CHROMATIC ABERRATION EFFECTS USING...A photon sieve is a lightweight diffractive optic which can be useful for space- based imaging applications. It is limited by chromatic

  8. Progressive buckling under both constant axial load and cyclic distortion

    International Nuclear Information System (INIS)

    Clement, G.; Acker, D.; Lebey, J.

    1988-09-01

    Thin structures submitted to compressive loads must be carefully designed to avoid any risk of ruin by buckling. The aim of this paper is, first, to evidence that the critical buckling load may be notably lowered when cyclic strains are added to the compressive load and, secondly, to propose a practical rule of prevention against the ruin due to the progressive buckling phenomenon. This rule is validated by the results of numerous tests related to the entire range of modes of buckling (i.e. from fully plastic to fully elastic). Practical cases of interest for its use could mainly be those where cyclic thermal stresses are involved

  9. Rescuing--a universal phenomenon.

    Science.gov (United States)

    Little, John

    2014-12-01

    Rescuing, where the person is delivered from the immediacy of their conundrum by another, complicates management. The object of this paper is to understand the difficulty in relinquishing the rescuing role. Rescuing is a universal phenomenon in parenting, teaching and therapy that has developed over time through a variety of interwoven social, economic, psychological and clinical variables. © The Royal Australian and New Zealand College of Psychiatrists 2014.

  10. Solid-Phase S-Alkylation Promoted by Molecular Sieves.

    Science.gov (United States)

    Calce, Enrica; Leone, Marilisa; Mercurio, Flavia Anna; Monfregola, Luca; De Luca, Stefania

    2015-11-20

    A solid-phase S-alkylation procedure to introduce chemical modification on the cysteine sulfhydryl group of a peptidyl resin is reported. The reaction is promoted by activated molecular sieves and consists of a solid-solid process, since both the catalyst and the substrate are in a solid state. The procedure was revealed to be efficient and versatile, particularly when used in combination with the solution S-alkylation approach, allowing for the introduction of different molecular diversities on the same peptide molecule.

  11. Absorption of radioiodine in silver nitrate molecular sieve

    International Nuclear Information System (INIS)

    Delfino, C.A.; Molinari, M.A.

    1983-01-01

    Obtainment method and control techniques of materials for the retention of radioiodine in gaseous effluents of nuclear installations. The experimental section is referred to the following processes: preparation of absorbents using, as basis, a molecular sieve and zeolite; impregnation with AgNO 3 ; efficiency determination; efficiency study as a function of the specific charge and bed length; optimization of Ag-consumption; resistance to the gas flux, bed temperature, specific surface, and nitrogen oxides effects. With the described impregnation method, materials, whose properties made them suitable for use in filters for the radioiodine retention and comparable to the imported manufactured materials, may be obtained. (R.J.S.) [es

  12. A differential delay equation arising from the sieve of Eratosthenes

    Science.gov (United States)

    Cheer, A. Y.; Goldston, D. A.

    1990-07-01

    The differential delay equation defined by ω (u) = 1/u for 1 ≤ u ≤ 2 and (uω (u))' = ω (u - 1) for u ≥ 2 was introduced by Buchstab in connection with an asymptotic formula for the number of uncanceled terms in the sieve of Eratosthenes. Maier has recently used this result to show there is unexpected irregularity in the distribution of primes in short intervals. The function ω (u) is studied in this paper using numerical and analytical techniques. The results are applied to give some numerical constants in Maier's theorem.

  13. Cyclic approximation to stasis

    Directory of Open Access Journals (Sweden)

    Stewart D. Johnson

    2009-06-01

    Full Text Available Neighborhoods of points in $mathbb{R}^n$ where a positive linear combination of $C^1$ vector fields sum to zero contain, generically, cyclic trajectories that switch between the vector fields. Such points are called stasis points, and the approximating switching cycle can be chosen so that the timing of the switches exactly matches the positive linear weighting. In the case of two vector fields, the stasis points form one-dimensional $C^1$ manifolds containing nearby families of two-cycles. The generic case of two flows in $mathbb{R}^3$ can be diffeomorphed to a standard form with cubic curves as trajectories.

  14. Accelerated cyclic corrosion tests

    Directory of Open Access Journals (Sweden)

    Prošek T.

    2016-06-01

    Full Text Available Accelerated corrosion testing is indispensable for material selection, quality control and both initial and residual life time prediction for bare and painted metallic, polymeric, adhesive and other materials in atmospheric exposure conditions. The best known Neutral Salt Spray (NSS test provides unrealistic conditions and poor correlation to exposures in atmosphere. Modern cyclic accelerated corrosion tests include intermittent salt spray, wet and dry phases and eventually other technical phases. They are able to predict the material performance in service more correctly as documented on several examples. The use of NSS should thus be restricted for quality control.

  15. A controllable molecular sieve for Na+ and K+ ions.

    Science.gov (United States)

    Gong, Xiaojing; Li, Jichen; Xu, Ke; Wang, Jianfeng; Yang, Hui

    2010-02-17

    The selective rate of specific ion transport across nanoporous material is critical to biological and nanofluidic systems. Molecular sieves for ions can be achieved by steric and electrical effects. However, the radii of Na(+) and K(+) are quite similar; they both carry a positive charge, making them difficult to separate. Biological ionic channels contain precisely arranged arrays of amino acids that can efficiently recognize and guide the passage of K(+) or Na(+) across the cell membrane. However, the design of inorganic channels with novel recognition mechanisms that control the ionic selectivity remains a challenge. We present here a design for a controllable ion-selective nanopore (molecular sieve) based on a single-walled carbon nanotube with specially arranged carbonyl oxygen atoms modified inside the nanopore, which was inspired by the structure of potassium channels in membrane spanning proteins (e.g., KcsA). Our molecular dynamics simulations show that the remarkable selectivity is attributed to the hydration structure of Na(+) or K(+) confined in the nanochannels, which can be precisely tuned by different patterns of the carbonyl oxygen atoms. The results also suggest that a confined environment plays a dominant role in the selectivity process. These studies provide a better understanding of the mechanism of ionic selectivity in the KcsA channel and possible technical applications in nanotechnology and biotechnology, including serving as a laboratory-in-nanotube for special chemical interactions and as a high-efficiency nanodevice for purification or desalination of sea and brackish water.

  16. Evaluation of Strontium Selectivity by Sandia Octahedral Molecular Sieves (SOMS).

    Energy Technology Data Exchange (ETDEWEB)

    Rigali, Mark J.; Stewart, Thomas Austin

    2016-01-01

    Sandia National Laboratories has collaborated with Pleasanton Ridge Research Company (PRRC) to determine whether Sandia Octahedral Molecular Sieves (SOMS) and modified SOMs materials can be synthesized in large batches and produced in granular form. Sandia National Laboratories tested these SOMS and its variants based in aqueous chemical environments for an application-based evaluation of material performance as a sorbent. Testing focused primarily on determining the distribution coefficients (K d ) and chemical selectivity SOMs for alkali earth (Sr) ions in aqueous and dilute seawater solutions. In general the well-crystallized SOMS materials tested exhibited very high K d values (>10 6 ) in distilled water but K d values dropped substantially (%7E10 2 -10 3 ) in the dilute seawater (3%). However, one set of SOMS samples (1.4.2 and 1.4.6) provided by PRRC yielded relatively high K d (approaching 10 4 ) in dilute seawater. Further examination of these samples by scanning electron microscopy (SEM) revealed the presence of at least two phases at least one of which may be accounting for the improved K d values in dilute seawater. Evaluation of Strontium Selectivity by Sandia Octahedral Molecular Sieves (SOMS) January 20, 2016

  17. Resonance phenomenon in classical cepheids

    International Nuclear Information System (INIS)

    Takeuti, Mine; Aikawa, Toshiki

    1981-01-01

    To investigate resonance phenomenon in classical cepheids, the non-linear radial oscillation of stars is studied based on the assumption that the non-adiabatic perturbation is expressed in terms of van der Pol's type damping. Two- and three-wave resonance in this system is applied to classical cepheids to describe their bump and double-mode behavior. The phase of bump and the depression of amplitude are explained for bump cepheids. The double-periodicity is shown by the enhancement of the third overtone in three-wave resonance. Non-linear effect on resonant period is also discussed briefly. (author)

  18. [Asthma and cyclic neutropenia].

    Science.gov (United States)

    Salazar Cabrera, A N; Berrón Pérez, R; Ortega Martell, J A; Onuma Takane, E

    1996-01-01

    We report a male with history of recurrent infections (recurrent oral aphtous disease [ROAD], middle ear infections and pharyngo amigdalitis) every 3 weeks since he was 7 months old. At the age of 3 years cyclic neutropenia was diagnosed with cyclic fall in the total neutrophil count in blood smear every 21 days and prophylactic antimicrobial therapy was indicated. Episodic events every 3 weeks of acute asthma and allergic rhinitis were detected at the age of 6 years old and specific immunotherapy to Bermuda grass was given during 3 years with markedly improvement in his allergic condition but not in the ROAD. He came back until the age of 16 with episodic acute asthma and ROAD. The total neutrophil count failed to 0 every 21 days and surprisingly the total eosinophil count increased up to 2,000 at the same time, with elevation of serum IgE (412 Ul/mL). Specific immunotherapy to D.pt. and Aller.a. and therapy with timomodulin was indicated. After 3 months we observed clinical improvement in the asthmatic condition and the ROAD disappeared, but the total neutrophil count did not improve. We present this case as a rare association between 2 diseases with probably no etiological relationship but may be physiopatological that could help to understand more the pathogenesis of asthma.

  19. Ekpyrotic and cyclic cosmology

    International Nuclear Information System (INIS)

    Lehners, Jean-Luc

    2008-01-01

    Ekpyrotic and cyclic cosmologies provide theories of the very early and of the very late universe. In these models, the big bang is described as a collision of branes - and thus the big bang is not the beginning of time. Before the big bang, there is an ekpyrotic phase with equation of state w=P/(ρ) >>1 (where P is the average pressure and ρ the average energy density) during which the universe slowly contracts. This phase resolves the standard cosmological puzzles and generates a nearly scale-invariant spectrum of cosmological perturbations containing a significant non-Gaussian component. At the same time it produces small-amplitude gravitational waves with a blue spectrum. The dark energy dominating the present-day cosmological evolution is reinterpreted as a small attractive force between our brane and a parallel one. This force eventually induces a new ekpyrotic phase and a new brane collision, leading to the idea of a cyclic universe. This review discusses the detailed properties of these models, their embedding in M-theory and their viability, with an emphasis on open issues and observational signatures

  20. Z₂-double cyclic codes

    OpenAIRE

    Borges, J.

    2014-01-01

    A binary linear code C is a Z2-double cyclic code if the set of coordinates can be partitioned into two subsets such that any cyclic shift of the coordinates of both subsets leaves invariant the code. These codes can be identified as submodules of the Z2[x]-module Z2[x]/(x^r − 1) × Z2[x]/(x^s − 1). We determine the structure of Z2-double cyclic codes giving the generator polynomials of these codes. The related polynomial representation of Z2-double cyclic codes and its duals, and the relation...

  1. Manual for Cyclic Triaxial Test

    DEFF Research Database (Denmark)

    Shajarati, Amir; Sørensen, Kris Wessel; Nielsen, Søren Kjær

    This manual describes the different steps that is included in the procedure for conducting a cyclic triaxial test at the geotechnical Laboratory at Aalborg University. Furthermore it contains a chapter concerning some of the background theory for the static triaxial tests. The cyclic/dynamic tria......This manual describes the different steps that is included in the procedure for conducting a cyclic triaxial test at the geotechnical Laboratory at Aalborg University. Furthermore it contains a chapter concerning some of the background theory for the static triaxial tests. The cyclic...

  2. Cracked-Mixture Sieving Rates And Efficiencies In Small-Scale ...

    African Journals Online (AJOL)

    A number of innovations, including the inclined manual rotary sieve or trommel, have been introduced by small-scale process equipment manufacturers and are being used in palm-nut cracked mixture separation. But the proficiency of these innovations has not been officially established. The study measures the sieving ...

  3. Phloem Ultrastructure and Pressure Flow: Sieve-Element-Occlusion-Related Agglomerations Do Not Affect Translocation

    DEFF Research Database (Denmark)

    Froelich, Daniel R.; Mullendore, Daniel L.; Jensen, Kåre Hartvig

    2011-01-01

    Since the first ultrastructural investigations of sieve tubes in the early 1960s, their structure has been a matter of debate. Because sieve tube structure defines frictional interactions in the tube system, the presence of P protein obstructions shown in many transmission electron micrographs le...

  4. Fractionation of distillers dried grains with solubles (DDGS) by sieving and winnowing.

    Science.gov (United States)

    Liu, KeShun

    2009-12-01

    Four commercial samples of distillers dried grains with solubles (DDGS) were sieved. All sieved fractions except for the pan fraction, constituting about 90% of original mass, were then winnowed with an air blast seed cleaner. Sieving was effective in producing fractions with varying composition. As the particle size decreased, protein and ash contents increased, and total carbohydrate (CHO) decreased. Winnowing sieved fractions was also effective in shifting composition, particularly for larger particle classes. Heavy sub-fractions were enriched in protein, oil and ash, while light sub-fractions were enriched for CHO. For protein, the combination of the two procedures resulted in a maximum 56.4% reduction in a fraction and maximum 60.2% increase in another fraction. As airflow velocity increased, light sub-fraction mass increased, while the compositional difference between the heavy and light sub-fractions decreased. Winnowing three times at a lower velocity was as effective as winnowing one time at a medium velocity. Winnowing the whole DDGS was much less effective than winnowing sieved fractions in changing composition, but sieving winnowed fractions was more effective than sieving whole DDGS. The two combination sequences gave comparable overall effects but sieving followed by winnowing is recommended because it requires less time. Regardless of combinational sequence, the second procedure was more effective in shifting composition than the first procedure.

  5. Studies on molecular sieves for the removal of moisture from air stream

    International Nuclear Information System (INIS)

    Kalra, S.; Ramarathinam, K.; Khan, A.A.

    1975-01-01

    Studies on molecular sieves were taken up with a view to provide sufficient experimental data for the design of an adsorbent bed for the removal of moisture to very low level from air stream containing traces of radioactive xenon and krypton, so that delay of xenon and krypton on activated charcoal columns can take place with a higher dynamic adsorption coefficient. Experimental studies included the evaluation of molecular sieves for their moisture removal efficiencies at different face velocities and different bed thicknesses. Adsorption capacity at removal efficiency of 98.5% was determined for molecular sieves type 4A of local and foreign origin. For local molecular sieves type 4A, adsorption capacity at 95% removal efficiency was found out at lower moisture contents of air streams. Regeneration characteristics of a saturated bed were also studied on local molecular sieves type 4A. (author)

  6. Molecular sieving through a graphene nanopore: non-equilibrium molecular dynamics simulation

    Institute of Scientific and Technical Information of China (English)

    Chengzhen Sun; Bofeng Bai

    2017-01-01

    Two-dimensional graphene nanopores have shown great promise as ultra-permeable molecular sieves based on their size-sieving effects.We design a nitrogen/hydrogen modified graphene nanopore and conduct a transient non-equilibrium molecular dynamics simulation on its molecular sieving effects.The distinct time-varying molecular crossing numbers show that this special nanopore can efficiently sieve CO2 and H2S molecules from CH4 molecules with high selectivity.By analyzing the molecular structure and pore functionalization-related molecular orientation and permeable zone in the nanopore,density distribution in the molecular adsorption layer on the graphene surface,as well as other features,the molecular sieving mechanisms of graphene nanopores are revealed.Finally,several implications on the design of highly-efficient graphene nanopores,especially for determining the porosity and chemical functionalization,as gas separation membranes are summarized based on the identified phenomena and mechanisms.

  7. A review of CCFL phenomenon

    International Nuclear Information System (INIS)

    Al Issa, S.; Macian, R.

    2011-01-01

    Highlights: → CCFL mechanisms, correlations, parameters and related variables were reviewed extensively. → Consideration of geometrical effects is crucial for meaningful comparison and review. → Differentiation between 'onset of CCFL' and 'deflooding/partial delivery' data is required. → Following 2+3, new correlations for onset of CCFL according to liquid velocity ranges were suggested. → Large number of correlations was compared against large data bank that considers points 2+3. - Abstract: Counter current flow limitation CCFL is an important phenomenon for numerous engineering applications and safety of light water reactors. In particular, the possible occurrence of CCFL in the hot-leg of a PWR during SBLOCA or LOCA accidents is of special interest for nuclear safety research. A review of the related literature has made in order to present the most important studies about the phenomenon and to reach common general understanding of the different factors that govern CCFL. Eventually this will allow explaining contradictions among different explanations provided by different authors. Most important factors were geometrical characteristics, liquid superficial velocity, and physical properties. The review shows that despite numerous experimental works, many scaling and geometrical effects are still not fully understood. For Instance there exist no consistent explanation of the channel diameter and inclined riser length effect upon results. The same can be stated-though to a minimum extent - for the inclination angle while channel length (or channel to diameter ratio) effect was clear and consistent. Since most experimental work was done in down-scaled hot-leg simulators, it becomes interesting to build a coherent knowledge about these effects and to explain arising contradictions in order to safely extrapolate results to full-scale hot-leg. The review has shown that many differences were simply due to geometrical effects, this leads to the need to

  8. The Phenomenon of Dental Fear

    DEFF Research Database (Denmark)

    Moore, Rod

    Odontophobia is a rather unique phobia with special psychosomatic components that impact on the dental health of odontophobic persons. It also has psychosocial components largely as a result of destruction of the teeth and subsequent embarrassment that can affect a person and cause a vicious cycle...... of dental fear (see fig. 1). The phenomenon is facilitated by misunderstandings and myths generated by both patients and dentists (see table 1 for examples). The most common reasons given in the literature for such strong fears of dental treatment are: 1) bad experiences in childhood for 85% of cases, 2......) feeling of powerlessness and lack of control over personal emotional reactions and over the social situation in the dental chair, 3) social learning processes in which the image of the dentist is cast in a negative light by the mass media or by the person's relatives or friends and 4) that the person has...

  9. New Phenomenon of Commercial Corruption

    Directory of Open Access Journals (Sweden)

    Krzysztof Nowakowski

    2011-07-01

    Full Text Available This article is about increase corruption in private sector as commercial corruption. This establishes a wide understanding of that phenomenon in social science and law. Corruption and bribery are types of fraud and are linked with the private sector too. Although certain types of corruption will decline as the private sector grows and consolidates, other new types involving private sector firms may increase. The commercial corruption can be described as relation inside of an organization and as relation between firms. Corruption in private sector in Poland is connected with social distrust and specific organizational culture, too. Commercial corruption is a familiar feature of their societies and has been the focus of law enforcement and institutional reform. Many others problems do not change the fact that such corruption is a new important problem and causes lost of competitiveness and creates a substitute for fair market and competition in Polish economy and abroad.

  10. Vascular diagnostics for Raynaud's phenomenon

    Directory of Open Access Journals (Sweden)

    Dinsdale G

    2014-10-01

    Full Text Available Graham Dinsdale, Ariane L Herrick Centre for Musculoskeletal Research, Institute of Inflammation and Repair, Salford Royal NHS Foundation Trust, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK Abstract: Raynaud's phenomenon (RP is common, and in most patients is primary (idiopathic when due to reversible vasospasm and does not progress to irreversible tissue injury. However, in those patients for whom RP is secondary to an underlying disease (eg, systemic sclerosis or atherosclerosis, progression to digital ulceration or critical ischemia can occur. Therefore, the key question for the clinician is “Why does this patient have RP?” Vascular diagnostics play a key role in answering this. In this review, we firstly discuss the different vascular investigations relevant to clinical practice: nail fold capillaroscopy (including the different methodologies for examining the nail fold capillaries, and the role of capillaroscopy in helping to differentiate between primary and systemic sclerosis-related RP, thermography (available in specialist centers, and evaluation of large vessel disease (for example, due to atherosclerosis. We then discuss research tools, mainly laser Doppler methods, including laser Doppler imaging and laser speckle contrast imaging. These are commercially available as complete imaging systems and are (relatively easy to use. The main current goal in vascular imaging research is to validate these novel state-of-the-art techniques as outcome measures of digital vascular disease, and then apply them in early and later phase studies of new treatment approaches, thus facilitating drug development programs. Keywords: Raynaud's phenomenon, systemic sclerosis, nail fold capillaroscopy, thermography, laser Doppler, angiography

  11. The arabidopsis cyclic nucleotide interactome

    KAUST Repository

    Donaldson, Lara Elizabeth

    2016-05-11

    Background Cyclic nucleotides have been shown to play important signaling roles in many physiological processes in plants including photosynthesis and defence. Despite this, little is known about cyclic nucleotide-dependent signaling mechanisms in plants since the downstream target proteins remain unknown. This is largely due to the fact that bioinformatics searches fail to identify plant homologs of protein kinases and phosphodiesterases that are the main targets of cyclic nucleotides in animals. Methods An affinity purification technique was used to identify cyclic nucleotide binding proteins in Arabidopsis thaliana. The identified proteins were subjected to a computational analysis that included a sequence, transcriptional co-expression and functional annotation analysis in order to assess their potential role in plant cyclic nucleotide signaling. Results A total of twelve cyclic nucleotide binding proteins were identified experimentally including key enzymes in the Calvin cycle and photorespiration pathway. Importantly, eight of the twelve proteins were shown to contain putative cyclic nucleotide binding domains. Moreover, the identified proteins are post-translationally modified by nitric oxide, transcriptionally co-expressed and annotated to function in hydrogen peroxide signaling and the defence response. The activity of one of these proteins, GLYGOLATE OXIDASE 1, a photorespiratory enzyme that produces hydrogen peroxide in response to Pseudomonas, was shown to be repressed by a combination of cGMP and nitric oxide treatment. Conclusions We propose that the identified proteins function together as points of cross-talk between cyclic nucleotide, nitric oxide and reactive oxygen species signaling during the defence response.

  12. Mesoporous Silica Molecular Sieve based Nanocarriers: Transpiring Drug Dissolution Research.

    Science.gov (United States)

    Pattnaik, Satyanarayan; Pathak, Kamla

    2017-01-01

    Improvement of oral bioavailability through enhancement of dissolution for poorly soluble drugs has been a very promising approach. Recently, mesoporous silica based molecular sieves have demonstrated excellent properties to enhance the dissolution velocity of poorly water-soluble drugs. Current research in this area is focused on investigating the factors influencing the drug release from these carriers, the kinetics of drug release and manufacturing approaches to scale-up production for commercial manufacture. This comprehensive review provides an overview of different methods adopted for synthesis of mesoporous materials, influence of processing factors on properties of these materials and drug loading methods. The drug release kinetics from mesoporous silica systems, the manufacturability and stability of these formulations are reviewed. Finally, the safety and biocompatibility issues related to these silica based materials are discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  13. Room temperature Sieving of Hydrogen Isotopes Using 2-D Materials

    Energy Technology Data Exchange (ETDEWEB)

    Hitchcock, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Colon-Mercado, H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Krentz, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Serkiz, S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Velten, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Xiao, S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-09-28

    Hydrogen isotope separation is critical to the DOE’s mission in environmental remediation and nuclear nonproliferation. Isotope separation is also a critical technology for the NNSA, and the ability to perform the separations at room temperature with a relatively small amount of power and space would be a major advancement for their respective missions. Recent work has shown that 2-D materials such as graphene and hexagonal boron nitride can act as an isotopic sieve at room temperature; efficiently separating hydrogen isotopes in water with reported separation ratios of 10:1 for hydrogen: deuterium separation for a single pass. The work performed here suggests that this technique has merit, and furthermore, we are investigating optimization and scale up of the required 2-D material based membranes.

  14. Standard Guide for Wet Sieve Analysis of Ceramic Whiteware Clays

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 This guide covers the wet sieve analysis of ceramic whiteware clays. This guide is intended for use in testing shipments of clay as well as for plant control tests. 1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  15. Mesoporous titanium phosphate molecular sieves with ion-exchange capacity.

    Science.gov (United States)

    Bhaumik, A; Inagaki, S

    2001-01-31

    Novel open framework molecular sieves, titanium(IV) phosphates named, i.e., TCM-7 and -8 (Toyota Composite Materials, numbers 7 and 8), with new mesoporous cationic framework topologies obtained by using both cationic and anionic surfactants are reported. The (31)P MAS NMR, UV-visible absorption, and XANES data suggest the tetrahedral state of P and Ti, and stabilization of the tetrahedral state of Ti in TCM-7/8 is due to the incorporation of phosphorus (at Ti/P = 1:1) vis-à-vis the most stable octahedral state of Ti in the pure mesoporous TiO(2). Mesoporous TCM-7 and -8 show anion exchange capacity due to the framework phosphonium cation and cation exchange capacity due to defective P-OH groups. The high catalytic activity in the liquid-phase partial oxidation of cyclohexene with a dilute H(2)O(2) oxidant supports the tetrahedral coordination of Ti in these materials.

  16. A Sieving ANN for Emotion-Based Movie Clip Classification

    Science.gov (United States)

    Watanapa, Saowaluk C.; Thipakorn, Bundit; Charoenkitkarn, Nipon

    Effective classification and analysis of semantic contents are very important for the content-based indexing and retrieval of video database. Our research attempts to classify movie clips into three groups of commonly elicited emotions, namely excitement, joy and sadness, based on a set of abstract-level semantic features extracted from the film sequence. In particular, these features consist of six visual and audio measures grounded on the artistic film theories. A unique sieving-structured neural network is proposed to be the classifying model due to its robustness. The performance of the proposed model is tested with 101 movie clips excerpted from 24 award-winning and well-known Hollywood feature films. The experimental result of 97.8% correct classification rate, measured against the collected human-judges, indicates the great potential of using abstract-level semantic features as an engineered tool for the application of video-content retrieval/indexing.

  17. Carbon dioxide sorption in a nanoporous octahedral molecular sieve

    Science.gov (United States)

    Williamson, Izaak; Nelson, Eric B.; Li, Lan

    2015-08-01

    We have performed first-principles density functional theory calculations, incorporated with van der Waals interactions, to study CO2 adsorption and diffusion in nanoporous solid—OMS-2 (Octahedral Molecular Sieve). We found the charge, type, and mobility of a cation, accommodated in a porous OMS-2 material for structural stability, can affect not only the OMS-2 structural features but also CO2 sorption performance. This paper targets K+, Na+, and Ba2+ cations. First-principles energetics and electronic structure calculations indicate that Ba2+ has the strongest interaction with the OMS-2 porous surface due to valence electrons donation to the OMS-2 and molecular orbital hybridization. However, the Ba-doped OMS-2 has the worst CO2 uptake capacity. We also found evidence of sorption hysteresis in the K- and Na-doped OMS-2 materials.

  18. Sieve analysis using the number of infecting pathogens.

    Science.gov (United States)

    Follmann, Dean; Huang, Chiung-Yu

    2017-12-14

    Assessment of vaccine efficacy as a function of the similarity of the infecting pathogen to the vaccine is an important scientific goal. Characterization of pathogen strains for which vaccine efficacy is low can increase understanding of the vaccine's mechanism of action and offer targets for vaccine improvement. Traditional sieve analysis estimates differential vaccine efficacy using a single identifiable pathogen for each subject. The similarity between this single entity and the vaccine immunogen is quantified, for example, by exact match or number of mismatched amino acids. With new technology, we can now obtain the actual count of genetically distinct pathogens that infect an individual. Let F be the number of distinct features of a species of pathogen. We assume a log-linear model for the expected number of infecting pathogens with feature "f," f=1,…,F. The model can be used directly in studies with passive surveillance of infections where the count of each type of pathogen is recorded at the end of some interval, or active surveillance where the time of infection is known. For active surveillance, we additionally assume that a proportional intensity model applies to the time of potentially infectious exposures and derive product and weighted estimating equation (WEE) estimators for the regression parameters in the log-linear model. The WEE estimator explicitly allows for waning vaccine efficacy and time-varying distributions of pathogens. We give conditions where sieve parameters have a per-exposure interpretation under passive surveillance. We evaluate the methods by simulation and analyze a phase III trial of a malaria vaccine. © 2017, The International Biometric Society.

  19. Biofuel manufacturing from woody biomass: effects of sieve size used in biomass size reduction.

    Science.gov (United States)

    Zhang, Meng; Song, Xiaoxu; Deines, T W; Pei, Z J; Wang, Donghai

    2012-01-01

    Size reduction is the first step for manufacturing biofuels from woody biomass. It is usually performed using milling machines and the particle size is controlled by the size of the sieve installed on a milling machine. There are reported studies about the effects of sieve size on energy consumption in milling of woody biomass. These studies show that energy consumption increased dramatically as sieve size became smaller. However, in these studies, the sugar yield (proportional to biofuel yield) in hydrolysis of the milled woody biomass was not measured. The lack of comprehensive studies about the effects of sieve size on energy consumption in biomass milling and sugar yield in hydrolysis process makes it difficult to decide which sieve size should be selected in order to minimize the energy consumption in size reduction and maximize the sugar yield in hydrolysis. The purpose of this paper is to fill this gap in the literature. In this paper, knife milling of poplar wood was conducted using sieves of three sizes (1, 2, and 4 mm). Results show that, as sieve size increased, energy consumption in knife milling decreased and sugar yield in hydrolysis increased in the tested range of particle sizes.

  20. Teknologi Proses Pembuatan Molecular Sieve TiZA Untuk Pemekatan Asam Nitrat

    Directory of Open Access Journals (Sweden)

    Ali Nurdin

    2017-10-01

    Full Text Available Molecular sieve zeolit dapat memurnikan campuran larutan yang bersifat azeotrop yang tidak bisa dilakukan menggunakan metode distilasi biasa. Namun, masih memiliki kelemahan dalam half life time molecular sieve tersebut, khususnya stabilitas bahan apabila digunakan pada larutan yang bersifat korosif seperti larutan asam atau basa. Pada penelitian ini telah  dilakukan pembuatan molecular sieve zeolit A yang dimodifikasi  dengan penambahan 10% titanium. Molecular sieve titanium - zeolit A (TiZA dibuat dengan dengan metode hidrotermal pada temperatur 110 °C dan kalsinasi pada temperatur 500 °C. Karakterisasi dilakukan antara lain menggunakan X-ray Diffraction (XRD, Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDX dan karakterisasi pori dengan metode physisorption menggunakan nitrogen pada temperatur 44 K. Molecular sieve TiZA yang dihasilkan stabil terhadap temperatur tinggi, dan larutan asam. Modifikasi zeolit A dengan titanium telah mampu meningkatkan stabilitas molecular sieve Ti-zeolit A dalam larutan asam nitrat selama 24 jam. Distribusi ukuran pori BJH (Barret Joyner Halenda  yang sempit menggambarkan ukuran yang homogen dengan didominasi oleh mikro porus dengan diameter rata-rata sekitar 4Å. Uji coba pemurnian asam nitrat dengan menggunakan molecular sieve secara single stage dapat meningkatkan kemurnian asam nitrat dari 70% hingga 85%.

  1. Leidenfrost phenomenon on conical surfaces

    Science.gov (United States)

    Hidalgo-Caballero, S.; Escobar-Ortega, Y.; Pacheco-Vázquez, F.

    2016-09-01

    The Leidenfrost state is typically studied by placing droplets on flat or slightly curved surfaces. Here this phenomenon is investigated by depositing water in hot conical bowls. We found that this phase exists even for large amounts of liquid in very narrow cones without considerable effect of the confinement on the Leidenfrost transition temperature TL. At a fixed temperature, T >TL , the total evaporation time τ has a nonmonotonic dependence on the angle of confinement θ : for large volumes (˜20 ml) on flat surfaces (θ ˜0∘ ), vapor chimneys appear and accelerate the evaporation rate, their frequency diminishes as θ augments and becomes zero at a certain angle θc, at which τ reaches its maximum value; then, τ decreases again at larger angles because the vapor layer holding up the water becomes thinner due to the increase of hydrostatic pressure and because the geometry facilitates the vapor expulsion along the conical wall. For small volumes (˜1 ml), surface tension mainly determines the drop curvature and the lifetime is practically independent of θ . Different chimney regimes and oscillation patterns were observed and summarized in a phase diagram. Finally, we developed a simple model to decipher the shape adopted by the liquid volume and its evolution as a function of time, and the predictions are in good agreement with the experimental results.

  2. P-protein distribution in mature sieve elements of Cucurbita maxima.

    Science.gov (United States)

    Evert, R F; Eschrich, W; Eichhorn, S E

    1972-09-01

    Portions of the hypocotyls of 16-day-old Cucurbita maxima plants, from which the cotyledons and first foliage leaves had been removed 2 days earlier, were fixed in glutaraldehyde and postfixed in osmium tetroxide for electron microscopy. In well over 90% of the mature sieve elements examined the P-protein was entirely parietal in distribution in both the lumina and sieve-plate pores. In addition to the parietal P-protein, the unoccluded sieve-plate pores were lined by narrow callose cylinders and the plasmalemma. Segments of endoplasmic reticulum also occurred along the margins of the pores.

  3. Synthesis and Characterization of Magnesium Substituted Aluminophosphate Molecular Sieves with AEL Structure

    Institute of Scientific and Technical Information of China (English)

    Benjing Xu; Ling Qian; Xinmei Liu; Chunmin Song; Zifeng Yan

    2004-01-01

    MAPO-11 molecular sieves were synthesized by hydrothermal methods. The influence of precursor of magnesium, Mg/Al ratio, synthesis temperature, synthesis time and the type of template on the formation and properties of MAPO-11 molecular sieves was examined. The samples were characterized by the techniques of X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric/differential thermogravimetric analysis (TG-DGA), etc. The results show that the shape and size of crystal were influenced by the precursor of Mg, the Mg/Al ratio and the type of template, and the TG-DGA analysis shows that MAPO-11 molecular sieves as-synthesized have poor thermal stability.

  4. Matrimid® derived carbon molecular sieve hollow fiber membranes for ethylene/ethane separation

    KAUST Repository

    Xu, Liren

    2011-09-01

    Carbon molecular sieve (CMS) membranes have shown promising separation performance compared to conventional polymeric membranes. Translating the very attractive separation properties from dense films to hollow fibers is important for applying CMS materials in realistic gas separations. The very challenging ethylene/ethane separation is the primary target of this work. Matrimid® derived CMS hollow fiber membranes have been investigated in this work. Resultant CMS fiber showed interesting separation performance for several gas pairs, especially high selectivity for C2H4/C2H6. Our comparative study between dense film and hollow fiber revealed very similar selectivity for both configurations; however, a significant difference exists in the effective separation layer thickness between precursor fibers and their resultant CMS fibers. SEM results showed that the deviation was essentially due to the collapse of the porous substructure of the precursor fiber. Polymer chain flexibility (relatively low glass transition temperature (Tg) for Matrimid® relative to actual CMS formation) appears to be the fundamental cause of substructure collapse. This collapse phenomenon must be addressed in all cases involving intense heat-treatment near or above Tg. We also found that the defect-free property of the precursor fiber was not a simple predictor of CMS fiber performance. Even some precursor fibers with Knudsen diffusion selectivity could be transformed into highly selective CMS fibers for the Matrimid® precursor. To overcome the permeance loss problem caused by substructure collapse, several engineering approaches were considered. Mixed gas permeation results under realistic conditions demonstrate the excellent performance of CMS hollow fiber membrane for the challenging ethylene/ethane separation. © 2011 Elsevier B.V.

  5. Prognosis of Cyclic Vomiting Syndrome

    Directory of Open Access Journals (Sweden)

    J. Gordon Millichap

    2016-03-01

    Full Text Available Investigators from Teikyo University School of Medicine, Tokyo, Japan, evaluated the clinical features, prognosis, and prophylaxis of cyclic vomiting syndrome and the relationship between the syndrome and levels of adrenocorticotropic/antidiuretic hormones (ACTH/ADH.

  6. Risk as a social phenomenon.

    Science.gov (United States)

    Jamison, Wesley V

    2003-01-01

    What do nuclear power, smoking, and eating beef have in common? The answer is multifaceted. They all share aspects of mass production and consumption, and therefore consumer confidence comes into play in evaluating each of the products' merits. They all produce some level of anxiety--be it in response to adverse media coverage, or the successes of adversarial interest groups in publicizing those products' weaknesses--among consumers who wonder what if any level of the product should be consumed. Finally, nuclear power, smoking, and eating beef all share risk; that is, the perceived and real detriments of producing and consuming those products. Whether or not the associated risks--from increased cancer to increased heart disease--are real is beside the point. When talking about risk, scientific education must deal with the perception of risk as much as its reality. Risk is a socially defined phenomenon, and as such, the successful scientists/communicator must understand the social evaluations of it. While many scientists take a rational view of risk evaluation and consumers often make rational decisions about technological and scientific risk based upon the costs and benefits of that technology, this approach is problematic for three reasons. First, the nature of modern risks has changed in that risk is complex, incomprehensible and uncontrollable to the average person. Second, the rational approach assumes that all costs and benefits of a technology, both real and potential, both current and future, can be known and therefore rationally evaluated. This is not the case. Third, evidence from Europe indicates that trust in information sources about risk has fallen, and thus classic scientific education campaigns that rely upon increasing public knowledge and acceptance of technological and scientific risk are problematic. Because of these factors we argue that effective scientific response must begin to understand the social components of risk if campaigns to shape

  7. Functionalized linear and cyclic polyolefins

    Energy Technology Data Exchange (ETDEWEB)

    Tuba, Robert; Grubbs, Robert H.

    2018-02-13

    This invention relates to methods and compositions for preparing linear and cyclic polyolefins. More particularly, the invention relates to methods and compositions for preparing functionalized linear and cyclic polyolefins via olefin metathesis reactions. Polymer products produced via the olefin metathesis reactions of the invention may be utilized for a wide range of materials applications. The invention has utility in the fields of polymer and materials chemistry and manufacture.

  8. Cyclic Processing for Context Fusion

    DEFF Research Database (Denmark)

    Kjærgaard, Mikkel Baun

    2007-01-01

    Many machine-learning techniques use feedback information. However, current context fusion systems do not support this because they constrain processing to be structured as acyclic processing. This paper proposes a generalization which enables the use of cyclic processing in context fusion systems....... A solution is proposed to the inherent problem of how to avoid uncontrollable looping during cyclic processing. The solution is based on finding cycles using graph-coloring and breaking cycles using time constraints....

  9. Carbon molecular sieve membranes derived from Matrimid® polyimide for nitrogen/methane separation

    KAUST Repository

    Ning, Xue; Koros, William J.

    2014-01-01

    A commercial polyimide, Matrimid® 5218, was pyrolyzed under an inert argon atmosphere to produce carbon molecular sieve (CMS) dense film membranes for nitrogen/methane separation. The resulting CMS dense film separation performance was evaluated

  10. Absolute molecular sieve separation of ethylene/ethane mixtures with silver zeolite A.

    Science.gov (United States)

    Aguado, Sonia; Bergeret, Gérard; Daniel, Cecile; Farrusseng, David

    2012-09-12

    Absolute ethylene/ethane separation is achieved by ethane exclusion on silver-exchanged zeolite A adsorbent. This molecular sieving type separation is attributed to the pore size of the adsorbent, which falls between ethylene and ethane kinetic diameters.

  11. An Ideal Molecular Sieve for Acetylene Removal from Ethylene with Record Selectivity and Productivity

    NARCIS (Netherlands)

    Li, B.; Cui, X.; O'Nolan, D.; Wen, H.-M.; Jiang, M.; Krishna, R.; Wu, H.; Lin, R.-B.; Chen, Y.-S.; Yuan, D.; Xing, H.; Zhou, W.; Ren, Q.; Qian, G.; Zaworotko, M.J.; Chen, B.

    2017-01-01

    Realization of ideal molecular sieves, in which the larger gas molecules are completely blocked without sacrificing high adsorption capacities of the preferred smaller gas molecules, can significantly reduce energy costs for gas separation and purification and thus facilitate a possible

  12. Structure–performance characterization for carbon molecular sieve membranes using molecular scale gas probes

    KAUST Repository

    Rungta, Meha; Xu, Liren; Koros, William J.

    2015-01-01

    © 2015 Elsevier Ltd. All rights reserved. Understanding the relationship between carbon molecular sieve (CMS) pore structure and corresponding gas separation performance enables optimization for a given gas separation application. The final

  13. Sieve analysis in HIV-1 vaccine efficacy trials.

    Science.gov (United States)

    Edlefsen, Paul T; Gilbert, Peter B; Rolland, Morgane

    2013-09-01

    The genetic characterization of HIV-1 breakthrough infections in vaccine and placebo recipients offers new ways to assess vaccine efficacy trials. Statistical and sequence analysis methods provide opportunities to mine the mechanisms behind the effect of an HIV vaccine. The release of results from two HIV-1 vaccine efficacy trials, Step/HVTN-502 (HIV Vaccine Trials Network-502) and RV144, led to numerous studies in the last 5 years, including efforts to sequence HIV-1 breakthrough infections and compare viral characteristics between the vaccine and placebo groups. Novel genetic and statistical analysis methods uncovered features that distinguished founder viruses isolated from vaccinees from those isolated from placebo recipients, and identified HIV-1 genetic targets of vaccine-induced immune responses. Studies of HIV-1 breakthrough infections in vaccine efficacy trials can provide an independent confirmation to correlates of risk studies, as they take advantage of vaccine/placebo comparisons, whereas correlates of risk analyses are limited to vaccine recipients. Through the identification of viral determinants impacted by vaccine-mediated host immune responses, sieve analyses can shed light on potential mechanisms of vaccine protection.

  14. Magnetic properties of iron loaded MCM-48 molecular sieves

    Energy Technology Data Exchange (ETDEWEB)

    Elias, Veronica R. [Centro de Investigacion y Tecnologia Quimica, Universidad Tecnologica Nacional, Facultad Regional Cordoba. Cordoba (Argentina); CONICET (Argentina); Oliva, Marcos I. [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba, Cordoba (Argentina); IFEG-CONICET (Argentina); Vaschetto, Eliana G. [Centro de Investigacion y Tecnologia Quimica, Universidad Tecnologica Nacional, Facultad Regional Cordoba. Cordoba (Argentina); Urreta, Silvia E., E-mail: urreta@famaf.unc.edu.a [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba, Cordoba (Argentina); Eimer, Griselda A. [Centro de Investigacion y Tecnologia Quimica, Universidad Tecnologica Nacional, Facultad Regional Cordoba. Cordoba (Argentina); CONICET (Argentina); Silvetti, Silvia P. [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba, Cordoba (Argentina)

    2010-11-15

    Mesoporous molecular sieves of MCM-48 type were loaded with iron by the wet impregnation method, using Fe(III) nitrate or Fe(II) sulfate aqueous solutions as Fe sources, to obtain a magnetic porous composite. The iron loaded materials were characterized by XRD, N{sub 2} adsorption and DRUV-vis and compared with the Si-MCM-48 host. Their magnetic properties were studied by measuring the hysteresis loops up to 1.5 T at different temperatures (5-300 K) and by magnetization vs. temperature curves following the conventional zero field cooling (ZFC) and field cooling (FC) protocols. Materials with high structure regularity and surface area are obtained, which exhibit a mixed paramagnetic and superparamagnetic behavior, arising in isolated iron ions inserted in the host framework, and in small iron oxide clusters or nanoparticles forming inside the pores, respectively. Larger hematite particles (8-13 nm) grown on the external surface provide a quite small ferromagnetic contribution to the hysteresis loop.

  15. Magnetic properties of iron loaded MCM-48 molecular sieves

    International Nuclear Information System (INIS)

    Elias, Veronica R.; Oliva, Marcos I.; Vaschetto, Eliana G.; Urreta, Silvia E.; Eimer, Griselda A.; Silvetti, Silvia P.

    2010-01-01

    Mesoporous molecular sieves of MCM-48 type were loaded with iron by the wet impregnation method, using Fe(III) nitrate or Fe(II) sulfate aqueous solutions as Fe sources, to obtain a magnetic porous composite. The iron loaded materials were characterized by XRD, N 2 adsorption and DRUV-vis and compared with the Si-MCM-48 host. Their magnetic properties were studied by measuring the hysteresis loops up to 1.5 T at different temperatures (5-300 K) and by magnetization vs. temperature curves following the conventional zero field cooling (ZFC) and field cooling (FC) protocols. Materials with high structure regularity and surface area are obtained, which exhibit a mixed paramagnetic and superparamagnetic behavior, arising in isolated iron ions inserted in the host framework, and in small iron oxide clusters or nanoparticles forming inside the pores, respectively. Larger hematite particles (8-13 nm) grown on the external surface provide a quite small ferromagnetic contribution to the hysteresis loop.

  16. Sieve of Eratosthenes benchmarks for the Z8 FORTH microcontroller

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, R.

    1989-02-01

    This report presents benchmarks for the Z8 FORTH microcontroller system that ORNL uses extensively in proving concepts and developing prototype test equipment for the Smart House Project. The results are based on the sieve of Eratosthenes algorithm, a calculation used extensively to rate computer systems and programming languages. Three benchmark refinements are presented,each showing how the execution speed of a FORTH program can be improved by use of a particular optimization technique. The last version of the FORTH benchmark shows that optimization is worth the effort: It executes 20 times faster than the Gilbreaths' widely-published FORTH benchmark program. The National Association of Home Builders Smart House Project is a cooperative research and development effort being undertaken by American home builders and a number of major corporations serving the home building industry. The major goal of the project is to help the participating organizations incorporate advanced technology in communications,energy distribution, and appliance control products for American homes. This information is provided to help project participants use the Z8 FORTH prototyping microcontroller in developing Smart House concepts and equipment. The discussion is technical in nature and assumes some experience with microcontroller devices and the techniques used to develop software for them. 7 refs., 5 tabs.

  17. MassSieve: Panning MS/MS peptide data for proteins

    OpenAIRE

    Slotta, Douglas J.; McFarland, Melinda A.; Markey, Sanford P.

    2010-01-01

    We present MassSieve, a Java-based platform for visualization and parsimony analysis of single and comparative LC-MS/MS database search engine results. The success of mass spectrometric peptide sequence assignment algorithms has led to the need for a tool to merge and evaluate the increasing data set sizes that result from LC-MS/MS-based shotgun proteomic experiments. MassSieve supports reports from multiple search engines with differing search characteristics, which can increase peptide sequ...

  18. Three Dimensional Digital Sieving of Asphalt Mixture Based on X-ray Computed Tomography

    OpenAIRE

    Chichun Hu; Jiexian Ma; M. Emin Kutay

    2017-01-01

    In order to perform three-dimensional digital sieving based on X-ray computed tomography images, the definition of digital sieve size (DSS) was proposed, which was defined as the minimum length of the minimum bounding squares of all possible orthographic projections of an aggregate. The corresponding program was developed to reconstruct aggregate structure and to obtain DSS. Laboratory experiments consisting of epoxy-filled aggregate specimens were conducted to investigate the difference betw...

  19. Phenomenon of fatigue in epitaxial films of lead zirconate-titanate

    International Nuclear Information System (INIS)

    Shur, V.Ya.; Ponomarev, N.Yu.; Tonkacheva, N.A.

    1997-01-01

    It is ascertained, that fatigue phenomenon under cyclic move in epitaxial heterostructures can be referred to incomplete move of c-domains and appearance of additional 90 gad domain walls in the domain structure, existing in a pause between pulses. fatigue kinetics is defined by the source domain structure parameters and must be essentially dependent both on conditions of luterostructure production and on the type of substrates

  20. P-proteins in Arabidopsis are heteromeric structures involved in rapid sieve tube sealing.

    Science.gov (United States)

    Jekat, Stephan B; Ernst, Antonia M; von Bohl, Andreas; Zielonka, Sascia; Twyman, Richard M; Noll, Gundula A; Prüfer, Dirk

    2013-01-01

    Structural phloem proteins (P-proteins) are characteristic components of the sieve elements in all dicotyledonous and many monocotyledonous angiosperms. Tobacco P-proteins were recently confirmed to be encoded by the widespread sieve element occlusion (SEO) gene family, and tobacco SEO proteins were shown to be directly involved in sieve tube sealing thus preventing the loss of photosynthate. Analysis of the two Arabidopsis SEO proteins (AtSEOa and AtSEOb) indicated that the corresponding P-protein subunits do not act in a redundant manner. However, there are still pending questions regarding the interaction properties and specific functions of AtSEOa and AtSEOb as well as the general function of structural P-proteins in Arabidopsis. In this study, we characterized the Arabidopsis P-proteins in more detail. We used in planta bimolecular fluorescence complementation assays to confirm the predicted heteromeric interactions between AtSEOa and AtSEOb. Arabidopsis mutants depleted for one or both AtSEO proteins lacked the typical P-protein structures normally found in sieve elements, underlining the identity of AtSEO proteins as P-proteins and furthermore providing the means to determine the role of Arabidopsis P-proteins in sieve tube sealing. We therefore developed an assay based on phloem exudation. Mutants with reduced AtSEO expression levels lost twice as much photosynthate following injury as comparable wild-type plants, confirming that Arabidopsis P-proteins are indeed involved in sieve tube sealing.

  1. Three Dimensional Digital Sieving of Asphalt Mixture Based on X-ray Computed Tomography

    Directory of Open Access Journals (Sweden)

    Chichun Hu

    2017-07-01

    Full Text Available In order to perform three-dimensional digital sieving based on X-ray computed tomography images, the definition of digital sieve size (DSS was proposed, which was defined as the minimum length of the minimum bounding squares of all possible orthographic projections of an aggregate. The corresponding program was developed to reconstruct aggregate structure and to obtain DSS. Laboratory experiments consisting of epoxy-filled aggregate specimens were conducted to investigate the difference between mechanical sieve analysis and the digital sieving technique. It was suggested that concave surface of aggregate was the possible reason for the disparity between DSS and mechanical sieve size. A comparison between DSS and equivalent diameter was also performed. Moreover, the digital sieving technique was adopted to evaluate the gradation of stone mastic asphalt mixtures. The results showed that the closest proximity of the laboratory gradation curve was achieved by calibrated DSS, among gradation curves based on calibrated DSS, un-calibrated DSS and equivalent diameter.

  2. Separation of krypton from carbon dioxide and oxygen with molecular sieves

    International Nuclear Information System (INIS)

    Forsberg, C.W.

    1976-01-01

    Molecular sieves were investigated to separate 1 percent mixtures of krypton in gas streams of a few percent oxygen and 90+ percent carbon dioxide. Such a system will be required to concentrate the krypton gas between radioactive krypton off-gas cleanup systems such as KALC (Krypton Absorption in Liquid Carbon Dioxide) and any krypton gas bottling station. Linde 5A molecular sieves were found capable of selectively removing the CO 2 from the gas stream while partially separating the oxygen from the krypton; i.e., effecting a three-component gas separation. This use of molecular sieves differs from standard practice in two respects. First, the bulk of the gas (greater than 90 percent) is removed by molecular sieves rather than the normal practice of using molecular sieves to remove trace impurities. Second, in a single bed two separations occur simultaneously, CO 2 from other gases and krypton from oxygen. The use of molecular sieves for separating krypton and carbon dioxide is superior to alternatives such as CO 2 freezeout and chemical traps when there are only moderate gas flows and there is a need for very high reliability and ease of maintenance

  3. [Rhytidectomy and Raynaud's phenomenon: about two cases].

    Science.gov (United States)

    Nicolas, J; Labbé, D

    2004-12-01

    Raynaud's phenomenon is a currently vascular syndrome (8 to 10% of women and 3 to 5% of men). It was defined as episodic ischaemia of the fingers, toes, nose, ears and nipples, which presents clinically as pallor, cyanosis, and often rubor of the skins, in response to cold, emotional stimuli and vasoconstriction agents. The phenomenon is caused by a vasoconstriction of arterials skin. In severe forms of the phenomenon, we can see ulcerations and necrosis. We report here two cases of rhytidectomy flap necrosis in Raynaud's Phenomenon. After review of literature, we explain the elements of physiopathology whose can explain these complications and we try to establish recommendations to these complications.

  4. Discrete numerical investigation of the ratcheting phenomenon in granular materials

    Science.gov (United States)

    Calvetti, Francesco; di Prisco, Claudio

    2010-10-01

    Several relevant geotechnical works, such as railway and road embankments, offshore foundations and vibrating machine foundations, are affected by the progressive accumulation of irreversible settlements. These latter represent the macroscopic evidence of the progressive rearrangement of particles under cycling loading, which is commonly referred to, in the literature, as ratcheting. This phenomenon is well known, but it is quite difficult to describe it by means of an appropriate constitutive model. As a consequence, the evaluation of durability of the aforementioned structures remains an open problem. In this article, the phenomenon will be approached by employing a Distinct Element model capable of describing the evolution of the microstructure induced by cyclic mechanical perturbations. Several analyses are performed in order to stress the influence of both the stress level and loading history on the mechanical response of a numerical model of a sand specimen. The numerical analyses are intended to provide an experimental background for conceiving a simplified macro approach based on generalised plasticity theory. In particular by means of probe test the plastic potential and the hardening parameters will be defined as a function of the current stress state and loading history.

  5. The biological quality of Sieve downriver the Sabatta waster water plant; La qualita biologica del fiume Sieve a valle del depuratore di Rabatta

    Energy Technology Data Exchange (ETDEWEB)

    Banchetti, Rosalba; Gasperini, Federico; Bicocchi, Allegra; Cecchini, Agnese; Nolan, Brigitte; Stramaccia, Tania [Pisa Univ., Pisa (Italy). Dipartimento di etologia, ecologia ed evoluzione

    2005-10-15

    An evaluation study of the environmental condition of Sieve river, based on the Extended Biotic Index method (E.B.I.) applied to macro invertebrates was carried out in 2003. Three sampling locations were selected upriver and downriver a depuration plant and upriver of the confluence of a tributary that flow into the Sieve, the Ensa. The monitoring, carried out in two separate campaigns, in winter and spring, revealed how efficient is the sludge-active plant in determining a good quality of the water. Moreover Bilancino reservoir, with constant discharges, keeps Sieve river flow with a constant regime all through the year, avoiding the summer dry-up of the river and allowing the settlement of a biodiversified macrobenthonic community. [Italian] Nal 2003 e stato condotto uno studio di valutazione dello stato ecologico del fiume Sieve sulla base della comunita di macroinvertebrati, usando il metodo dell'I.B.E. (Indice Biotico Esteso). Sono stati scelti tre punti di campionamento a monte e a valle dello scarico di un impianto di depurazione, in funzione dal 1998, che tratta reflui di origine civile. Il monitoraggio eseguito ha rivelato l'utilita dell'impianto a fanghi attivi nel determinare un netto miglioramento della qualita delle acque.

  6. Kierkegaard and the Sheer Phenomenon of Love

    DEFF Research Database (Denmark)

    Søltoft, Pia

    2013-01-01

    In this article we will argue that Kierkegaard has a positive view of love as a sheer natural and universal phenomenon. This sheer phenomenon of love is rooted in God’s love and is implanted in human nature by its Creator. Therefore this natural urge to love, that manifests itself both as a lack...

  7. Terrorism as a Social and Legal Phenomenon

    Science.gov (United States)

    Serebrennikova, Anna; Mashkova, Yekaterina

    2017-01-01

    This article examines the concept of terrorism as a social and legal phenomenon, its international legal and criminal-legal characteristics. Highlighted are the main aspects of cooperation of the states and the international community to counter terrorist activities. Terrorism as a social phenomenon is determined by paragraph 1 of article 3 of the…

  8. On Improvements of Cyclic MUSIC

    Directory of Open Access Journals (Sweden)

    H. Howard Fan

    2005-01-01

    Full Text Available Many man-made signals encountered in communications exhibit cyclostationarity. By exploiting cyclostationarity, cyclic MUSIC has been shown to be able to separate signals with different cycle frequencies, thus, to be able to perform signal selective direction of-arrival (DOA estimation. However, as will be shown in this paper, the DOA estimation of cyclic MUSIC is actually biased. We show in this paper that by properly choosing the frequency for evaluating the steering vector, the bias of DOA estimation can be substantially reduced and the performance can be improved. Furthermore, we propose another algorithm exploiting cyclic conjugate correlation to further improve the performance of DOA estimation. Simulation results show the effectiveness of both of our methods.

  9. MOBBING PHENOMENON - FACTORS OF DISCRIMINATION AND STRESS

    Directory of Open Access Journals (Sweden)

    ROMANESCU MARCEL LAURENTIU

    2017-02-01

    Full Text Available This article focuses on exemplifying the features of discrimination phenomenon in the workplace, a phenomenon that has appeared in the Romanian social studies only in the last 4 years. Mobbing phenomenon has been analyzed by several countries in Europe such as England, France, Germany; after these analyzes it has been found that this phenomenon refers only to actions of intense psychological pressure. Actions are geared to a single employee, in order to cause it to leave its job. Without these measures, dismissal of the employee would lead to numerous legal problems on the employer. In conclusion, employee who is the subject of mobbing phenomenon must endure a long period of time a series of injustices focused on himself, but also extremely high humiliation, which determines him to mentally give up and take the decision to resign.

  10. Sieve element occlusion (SEO) genes encode structural phloem proteins involved in wound sealing of the phloem.

    Science.gov (United States)

    Ernst, Antonia M; Jekat, Stephan B; Zielonka, Sascia; Müller, Boje; Neumann, Ulla; Rüping, Boris; Twyman, Richard M; Krzyzanek, Vladislav; Prüfer, Dirk; Noll, Gundula A

    2012-07-10

    The sieve element occlusion (SEO) gene family originally was delimited to genes encoding structural components of forisomes, which are specialized crystalloid phloem proteins found solely in the Fabaceae. More recently, SEO genes discovered in various non-Fabaceae plants were proposed to encode the common phloem proteins (P-proteins) that plug sieve plates after wounding. We carried out a comprehensive characterization of two tobacco (Nicotiana tabacum) SEO genes (NtSEO). Reporter genes controlled by the NtSEO promoters were expressed specifically in immature sieve elements, and GFP-SEO fusion proteins formed parietal agglomerates in intact sieve elements as well as sieve plate plugs after wounding. NtSEO proteins with and without fluorescent protein tags formed agglomerates similar in structure to native P-protein bodies when transiently coexpressed in Nicotiana benthamiana, and the analysis of these protein complexes by electron microscopy revealed ultrastructural features resembling those of native P-proteins. NtSEO-RNA interference lines were essentially devoid of P-protein structures and lost photoassimilates more rapidly after injury than control plants, thus confirming the role of P-proteins in sieve tube sealing. We therefore provide direct evidence that SEO genes in tobacco encode P-protein subunits that affect translocation. We also found that peptides recently identified in fascicular phloem P-protein plugs from squash (Cucurbita maxima) represent cucurbit members of the SEO family. Our results therefore suggest a common evolutionary origin for P-proteins found in the sieve elements of all dicotyledonous plants and demonstrate the exceptional status of extrafascicular P-proteins in cucurbits.

  11. Design of a cyclic multiverse

    Energy Technology Data Exchange (ETDEWEB)

    Piao Yunsong, E-mail: yspiao@gucas.ac.c [College of Physical Sciences, Graduate School of Chinese Academy of Sciences, Beijing 100049 (China)

    2010-08-09

    Recently, it has been noticed that the amplification of the amplitude of curvature perturbation cycle by cycle can lead to a cyclic multiverse scenario, in which the number of universes increases cycle by cycle. However, this amplification will also inevitably induce either the ultimate end of corresponding cycle, or the resulting spectrum of perturbations inside corresponding universe is not scale invariant, which baffles the existence of observable universes. In this Letter, we propose a design of a cyclic multiverse, in which the observable universe can emerges naturally. The significance of a long period of dark energy before the turnaround of each cycle for this implementing is shown.

  12. Design of a cyclic multiverse

    International Nuclear Information System (INIS)

    Piao Yunsong

    2010-01-01

    Recently, it has been noticed that the amplification of the amplitude of curvature perturbation cycle by cycle can lead to a cyclic multiverse scenario, in which the number of universes increases cycle by cycle. However, this amplification will also inevitably induce either the ultimate end of corresponding cycle, or the resulting spectrum of perturbations inside corresponding universe is not scale invariant, which baffles the existence of observable universes. In this Letter, we propose a design of a cyclic multiverse, in which the observable universe can emerges naturally. The significance of a long period of dark energy before the turnaround of each cycle for this implementing is shown.

  13. Nature of a solar cyclicity

    International Nuclear Information System (INIS)

    Romanchuk, P.R.

    1981-01-01

    The paper contains a critical review of works on studying a cyclic character of solar activity. An introduction of cyclic curves with a frequency spectrum is established to be insolvent. The Wolf, Newcomb and Waldmeier approach seems to be useful. Some evidence is given in favour of the author's conception of solar activity ciclicity of a tide nature. It is accounted for a continuous double and single effect of planets, a resonant character of this effect due to which a 10-year period of Jupiter and Saturn is transformed into an 11-year cycle of activity [ru

  14. Synthesis of mesoporous SAPO-34 molecular sieves and their applications in dehydration of butanols and ethanol.

    Science.gov (United States)

    Jun, Jong Won; Jeon, Jaewoo; Kim, Chul-Ung; Jeong, Kwang-Eun; Jeong, Soon-Yong; Jhung, Sung Hwa

    2013-04-01

    Microporous SAPO-34 molecular sieves were hydrothermally synthesized with microwave irradiation in the presence of tetraethylammonium hydroxide (TEAOH) as a template. SAPO-34 molecular sieves with mesoporosity were also prepared in the presence of carbon black as a hard template. By increasing the content of the carbon black template in the synthesis, the mesopore volume increased. Dehydration of alcohols (butanols and ethanol) was carried out with the synthesized SAPO-34 molecular sieves, and the lifetime of the catalysts for the dehydration reaction increased as the mesoporosity increased. Moreover, the performance of the microporous catalyst synthesized with microwave was better than that of the catalyst obtained with conventional electric heating. The relative performance of the catalytic dehydration may be explained by the mesoporosity and the crystal size. Therefore, it may be concluded that small-sized SAPO-34 molecular sieves with high mesoporosity can be produced efficiently with microwave irradiation in the presence of carbon black template, and the molecular sieves are effective in the stable dehydration of alcohols.

  15. P-proteins in Arabidopsis are heteromeric structures involved in rapid sieve tube sealing

    Directory of Open Access Journals (Sweden)

    Stephan B Jekat

    2013-07-01

    Full Text Available Structural phloem proteins (P-proteins are characteristic components of the sieve elements in all dicotyledonous and many monocotyledonous angiosperms. Tobacco P-proteins were recently evidenced to be encoded by the widespread SEO gene family, and tobacco SEO proteins were shown to be directly involved in sieve tube sealing thus preventing the loss of photosynthate. Analysis of the two Arabidopsis SEO proteins (AtSEOa and AtSEOb indicated that the corresponding P-protein subunits do not act in a redundant manner. However, there are still pending questions regarding the interaction properties and specific functions of AtSEOa and AtSEOb as well as the general function of structural P-proteins in Arabidopsis. In this study, we characterized the Arabidopsis P-proteins in more detail. We used in planta bimolecular fluorescence complementation assays to confirm the predicted heteromeric interactions between AtSEOa and AtSEOb. Arabidopsis mutants depleted for one or both AtSEO proteins lacked the typical P-protein structures normally found in sieve elements, underlining the identity of AtSEO proteins as P-proteins and furthermore providing the means to determine the role of Arabidopsis P-proteins in sieve tube sealing. We therefore developed an assay based on phloem exudation. Mutants with reduced AtSEO expression levels lost twice as much photosynthate following injury as comparable wild-type plants, confirming that Arabidopsis P-proteins are indeed involved in sieve tube sealing. 

  16. Mechanistic modeling of the loss of protein sieving due to internal and external fouling of microfilters.

    Science.gov (United States)

    Bolton, Glen R; Apostolidis, Alex J

    2017-09-01

    Fed-batch and perfusion cell culture processes used to produce therapeutic proteins can use microfilters for product harvest. In this study, new explicit mathematical models of sieving loss due to internal membrane fouling, external membrane fouling, or a combination of the two were generated. The models accounted for membrane and cake structures and hindered solute transport. Internal membrane fouling was assumed to occur due to the accumulation of foulant on either membrane pore walls (pore-retention model) or membrane fibers (fiber-retention model). External cake fouling was assumed to occur either by the growth of a single incompressible cake layer (cake-growth) or by the accumulation of a number of independent cake layers (cake-series). The pore-retention model was combined with either the cake-series or cake-growth models to obtain models that describe internal and external fouling occurring either simultaneously or sequentially. The models were tested using well-documented sieving decline data available in the literature. The sequential pore-retention followed by cake-growth model provided a good fit of sieving decline data during beer microfiltration. The cake-series and cake-growth models provided good fits of sieving decline data during the microfiltration of a perfusion cell culture. The new models provide insights into the mechanisms of fouling that result in the loss of product sieving. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1323-1333, 2017. © 2017 American Institute of Chemical Engineers.

  17. Glomerular sieving of high molecular weight proteins in proteinuric rats

    International Nuclear Information System (INIS)

    Bertolatus, J.A.; Abuyousef, M.; Hunsicker, L.G.

    1987-01-01

    To characterize the permeability of the glomerular capillary wall to high molecular weight proteins in normal and proteinuric rats, we determined the glomerular sieving coefficients (GSC) of radioiodinated marker proteins of known size and charge by means of a paired label, tissue accumulation method previously validated in this laboratory. In one group of rats (Series A) the GSCs of 125 I-anionic IgG (aIgG-molecular weight [mol wt] 150,000, pI 4.9) and 131 I-neutral IgG (nIgG-pI 7.4 to 7.6) were measured simultaneously. In Series B, the GSC of a second anionic marker, 131 I-human ceruloplasmin (Crp-mol wt 137,000, pI 4.9) was compared to that of 125 I-nIgG. As in the previous report, the labeled proteins were not degraded or deiodinated during the 20 minute clearance period for GSC determination. Within Series A and B, three subgroups of rats were studied: control saline-infused rats, rats made acutely proteinuric by infusion of the polycation hexadimethrine (HDM), and rats with chronic doxorubicin (Adriamycin-Adria) nephrosis. In the control rats, GSCs for the anionic markers aIgG (Series A) or Crp (Series B) were significantly greater than that of nIgG (both series). These large proteins crossed the filtration barrier by a different pathway from that available to smaller neutral molecules the size of albumin, which in our previous study had a much higher GSC than a native, anionic albumin marker. In a third group of control rats only (Series C), the GSCs of native anionic bovine albumin (BSA) and nIgG were compared directly. The GSC of BSA (0.0029) was only slightly larger than the GSC of nIgG (0.0025), indicating that most of the native albumin crosses the glomerular capillary wall via a nonselective pathway similar to that available to nIgG. The results in the control groups are compatible with recently-described heteroporous models of glomerular size selectivity

  18. Cyclic delivery scheduling to customers with different priorities

    Directory of Open Access Journals (Sweden)

    Katarzyna Zofia Gdowska

    2013-12-01

    Full Text Available Background: In this paper a cyclic delivery scheduling problem for customers with different priorities is presented. Shops, which are provided with deliveries, are occasionally located in places which are crucial for the proper flow of traffic. In such places coordination of deliveries is crucial; therefore it allows to completely eliminate the phenomenon of the simultaneous arrivals of suppliers. Methods: In this paper the cyclic delivery scheduling problem for customers with different priorities was presented. To this theoretical problem a mix integer programming model was developed. Specific approach to the cyclic delivery scheduling problem is inspired by timetabling problem for urban public transport. Results: Mixed integer programming model was employed for solving four cases of cyclic delivery scheduling problem for customers with different priorities. When the value of the synchronization priority assigned to a single customer raised then the total number of synchronizations in the whole network decreased. In order to compare solutions a synchronization rate was utilized. A simple factor was utilized - the proportion of number of synchronizations of deliveries to a given customer to the total number of synchronizations obtained for the whole network. When the value of synchronization priority raised then the value of synchronization rate of this customer improved significantly. Conclusions: The mixed integer programming model for the cyclic delivery scheduling problem for customers with different priorities presented in this paper can be utilized for generating schedules of serving customers located in places where only one delivery can be received and unloaded at one go and where there is no space for other suppliers to wait in a queue. Such a schedule can be very useful for organizing deliveries to small shops united in a franchising network, since they operate in a way that is very similar to the network presented in this paper

  19. Atomistic understanding of hydrogen loading phenomenon into ...

    Indian Academy of Sciences (India)

    IASBS), ... ically through various electrochemical methods and high-level quantum ... ton) by applying a constant anodic voltage. .... phenomenon being occurred at metal | solution inter- .... cationic form and extra energy is released by occupying.

  20. Cyclic creep-rupture behavior of three high-temperature alloys.

    Science.gov (United States)

    Halford, G. R.

    1972-01-01

    Study of some important characteristics of the cyclic creep-rupture curves for the titanium alloy 6Al-2Sn-4Zr-2Mo at 900 and 1100 F (755 and 865 K), the cobalt-base alloy L-605 at 1180 F (910 K), and for two hardness levels of 316 stainless steel at 1300 F (980 K). The cyclic creep-rupture curve relates tensile stress and tensile time-to-rupture for strain-limited cyclic loading and has been found to be independent of the total strain range and the level of compressive stress employed in the cyclic creep-rupture tests. The cyclic creep-rupture curve was always found to be above and to the right of the conventional (constant load) monotonic creep-rupture curve by factors ranging from 2 to 10 in time-to-rupture. This factor tends to be greatest when the creep ductility is large. Cyclic creep acceleration was observed in every cyclic creep-rupture test conducted. The phenomenon was most pronounced at the highest stress levels and when the tensile and compressive stresses were completely reversed. In general, creep rates were found to be lower in compression than in tension for equal true stresses. The differences, however, were strongly material-dependent.

  1. Koebner phenomenon of the ear canal skin.

    LENUS (Irish Health Repository)

    Young, O

    2012-02-01

    The Koebner phenomenon originally described the appearance of psoriatic lesions in the uninvolved skin of patients with psoriasis as a consequence of trauma. We describe a case of concurrent lichen planus and sarcoidosis in the auditory canal, which represents an unusual manifestation of the Koebner phenomenon. This is the first case of concurrent lichen planus and sarcoidosis in the head and neck region and highlights the need for biopsy to allow accurate histopathological diagnosis and treatment.

  2. Koebner phenomenon of the ear canal skin.

    LENUS (Irish Health Repository)

    Young, O

    2009-02-01

    The Koebner phenomenon originally described the appearance of psoriatic lesions in the uninvolved skin of patients with psoriasis as a consequence of trauma. We describe a case of concurrent lichen planus and sarcoidosis in the auditory canal, which represents an unusual manifestation of the Koebner phenomenon. This is the first case of concurrent lichen planus and sarcoidosis in the head and neck region and highlights the need for biopsy to allow accurate histopathological diagnosis and treatment.

  3. Job Insecurity as a Social Psychological Phenomenon

    Directory of Open Access Journals (Sweden)

    Chuykova T.S.

    2015-12-01

    Full Text Available The paper addresses a relatively new phenomenon of job insecurity. It provides an analysis of the various interpretations of the phenomenon given by Russian and foreign researchers, focuses on its social economical determinants and consequences for individuals and organizations. The paper concludes with an outline of some possible ways of overcoming the negative consequences of job insecurity — as for individuals, as for organizations, as for the society as a whole.

  4. Open source innovation phenomenon, participant behaviour, impact

    CERN Document Server

    Herstatt, Cornelius

    2015-01-01

    Open Source Innovation (OSI) has gained considerable momentum within the last years. Academic and management practice interest grows as more and more end-users consider and even participate in Open Source product development like Linux, Android, or Wikipedia. Open Source Innovation: Phenomenon, Participant Behaviour, Impact brings together rigorous academic research and business importance in scrutinizing OCI from three perspectives: The Phenomenon, Participants' Behavior, and Business Implications. The first section introduces OCI artefacts, including who is participating and why, and provide

  5. Deformation mechanisms in cyclic creep and fatigue

    International Nuclear Information System (INIS)

    Laird, C.

    1979-01-01

    Service conditions in which static and cyclic loading occur in conjunction are numerous. It is argued that an understanding of cyclic creep and cyclic deformation are necessary both for design and for understanding creep-fatigue fracture. Accordingly a brief, and selective, review of cyclic creep and cyclic deformation at both low and high strain amplitudes is provided. Cyclic loading in conjunction with static loading can lead to creep retardation if cyclic hardening occurs, or creep acceleration if softening occurs. Low strain amplitude cyclic deformation is understood in terms of dislocation loop patch and persistent slip band behavior, high strain deformation in terms of dislocation cell-shuttling models. While interesting advances in these fields have been made in the last few years, the deformation mechanisms are generally poorly understood

  6. Sequencing Cyclic Peptides by Multistage Mass Spectrometry

    Science.gov (United States)

    Mohimani, Hosein; Yang, Yu-Liang; Liu, Wei-Ting; Hsieh, Pei-Wen; Dorrestein, Pieter C.; Pevzner, Pavel A.

    2012-01-01

    Some of the most effective antibiotics (e.g., Vancomycin and Daptomycin) are cyclic peptides produced by non-ribosomal biosynthetic pathways. While hundreds of biomedically important cyclic peptides have been sequenced, the computational techniques for sequencing cyclic peptides are still in their infancy. Previous methods for sequencing peptide antibiotics and other cyclic peptides are based on Nuclear Magnetic Resonance spectroscopy, and require large amount (miligrams) of purified materials that, for most compounds, are not possible to obtain. Recently, development of mass spectrometry based methods has provided some hope for accurate sequencing of cyclic peptides using picograms of materials. In this paper we develop a method for sequencing of cyclic peptides by multistage mass spectrometry, and show its advantages over single stage mass spectrometry. The method is tested on known and new cyclic peptides from Bacillus brevis, Dianthus superbus and Streptomyces griseus, as well as a new family of cyclic peptides produced by marine bacteria. PMID:21751357

  7. Cyclic peptide therapeutics: past, present and future.

    Science.gov (United States)

    Zorzi, Alessandro; Deyle, Kaycie; Heinis, Christian

    2017-06-01

    Cyclic peptides combine several favorable properties such as good binding affinity, target selectivity and low toxicity that make them an attractive modality for the development of therapeutics. Over 40 cyclic peptide drugs are currently in clinical use and around one new cyclic peptide drug enters the market every year on average. The vast majority of clinically approved cyclic peptides are derived from natural products, such as antimicrobials or human peptide hormones. New powerful techniques based on rational design and in vitro evolution have enabled the de novo development of cyclic peptide ligands to targets for which nature does not offer solutions. A look at the cyclic peptides currently under clinical evaluation shows that several have been developed using such techniques. This new source for cyclic peptide ligands introduces a freshness to the field, and it is likely that de novo developed cyclic peptides will be in clinical use in the near future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Validation of the Impostor Phenomenon among Managers.

    Science.gov (United States)

    Rohrmann, Sonja; Bechtoldt, Myriam N; Leonhardt, Mona

    2016-01-01

    Following up on earlier investigations, the present research aims at validating the construct impostor phenomenon by taking other personality correlates into account and to examine whether the impostor phenomenon is a construct in its own right. In addition, gender effects as well as associations with dispositional working styles and strain are examined. In an online study we surveyed a sample of N = 242 individuals occupying leadership positions in different sectors. Confirmatory factor analyses provide empirical evidence for the discriminant validity of the impostor phenomenon. In accord with earlier studies we show that the impostor phenomenon is accompanied by higher levels of anxiety, dysphoric moods, emotional instability, a generally negative self-evaluation, and perfectionism. The study does not reveal any gender differences concerning the impostor phenomenon. With respect to working styles, persons with an impostor self-concept tend to show perfectionist as well as procrastinating behaviors. Moreover, they report being more stressed and strained by their work. In sum, the findings show that the impostor phenomenon constitutes a dysfunctional personality style. Practical implications are discussed.

  9. PP composites with Hybrid Nanofillers: NTC phenomenon

    International Nuclear Information System (INIS)

    Sarlin, Juha; Immonen, Kirsi

    2010-01-01

    Electric conductive plastic composites have a wide potential for commercial applications, some examples are EMI shielding housings and components in automotive industry and in consumer electronics, equipments in health care sector and fuel cell components. A phenomenon in conductive composites, especially in composites with carbon based fillers, is change of thermal induced change in conductivity as a result of morphological transitions. Usually the observed changes are practically irreversible. The phenomenon may cause increasing resistivity, usually called as 'positive temperature coefficient' (PTC) or decreasing resistivity, called 'negative temperature coefficient' (NTC), where the new morphology created by heat treatment is more favorable for electric conductivity compared to the original state. The existence of NTC is a sing of the lost potential in material design and processing. Therefore detailed information about the phenomenon gives us tools to develop high performance conductive materials. It this paper we discuss about NTC phenomenon observed in PP composites with CNT or in-situ synthesized CNT-PANi hybrid nanofiller with an amphiphilic dispersing agent. The goal of the paper is not to present a comprehensive model of this phenomenon; we present some experimental results which may be related to polymer-filler interactions. These details are a part of this complicated phenomenon.

  10. The biological quality of Sieve downriver the Sabatta waster water plant

    International Nuclear Information System (INIS)

    Banchetti, Rosalba; Gasperini, Federico; Bicocchi, Allegra; Cecchini, Agnese; Nolan, Brigitte; Stramaccia, Tania

    2005-01-01

    An evaluation study of the environmental condition of Sieve river, based on the Extended Biotic Index method (E.B.I.) applied to macro invertebrates was carried out in 2003. Three sampling locations were selected upriver and downriver a depuration plant and upriver of the confluence of a tributary that flow into the Sieve, the Ensa. The monitoring, carried out in two separate campaigns, in winter and spring, revealed how efficient is the sludge-active plant in determining a good quality of the water. Moreover Bilancino reservoir, with constant discharges, keeps Sieve river flow with a constant regime all through the year, avoiding the summer dry-up of the river and allowing the settlement of a biodiversified macrobenthonic community [it

  11. Ball mill tool for crushing coffee and cocoa beans base on fraction size sieving results

    Science.gov (United States)

    Haryanto, B.; Sirait, M.; Azalea, M.; Alvin; Cahyani, S. E.

    2018-02-01

    Crushing is one of the operation units that aimed to convert the size of solid material to be smoother particle’s size. The operation unit that can be used in this crushing is ball mill. The purpose of this study is to foresee the effect of raw material mass, grinding time, and the number of balls that are used in the ball mill tool related to the amount of raw material of coffee and cocoa beans. Solid material that has become smooth is then sieved with sieve mesh with size number: 50, 70, 100, and 140. It is in order to obtain the mass fraction that escaped from each sieve mesh. From the experiment, it can be concluded that mass percentage fraction of coffee powder is bigger than cocoa powder that escaped from the mesh. Hardness and humidity of coffee beans and cocoa beans have been the important factors that made coffee beans is easier to be crushed than cocoa beans.

  12. An early nodulin-like protein accumulates in the sieve element plasma membrane of Arabidopsis

    DEFF Research Database (Denmark)

    Khan, Junaid A.; Wang, Qi; Sjölund, Richard D.

    2007-01-01

    Membrane proteins within the sieve element-companion cell complex have essential roles in the physiological functioning of the phloem. The monoclonal antibody line RS6, selected from hybridomas raised against sieve elements isolated from California shield leaf (Streptanthus tortuosus; Brassicaceae...... was revealed by reverse transcription-PCR of Arabidopsis leaf RNA using degenerate primers to be an early nodulin (ENOD)-like protein that is encoded by the expressed gene At3g20570. Arabidopsis ENOD-like proteins are encoded by a multigene family composed of several types of structurally related phytocyanins...... from the precursor protein, resulting in a mature peptide of approximately 15 kD that is attached to the sieve element plasma membrane via a carboxy-terminal glycosylphosphatidylinositol membrane anchor. Many of the Arabidopsis ENOD-like proteins accumulate in gametophytic tissues, whereas in both...

  13. In-situ preparation of functionalized molecular sieve material and a methodology to remove template

    Science.gov (United States)

    Yadav, Rekha; Ahmed, Maqsood; Singh, Arvind Kumar; Sakthivel, Ayyamperumal

    2016-03-01

    A series of diaminosilane-functionalized silicoaluminophosphate molecular sieve (SAPO-37) was prepared by in-situ synthesis, and a novel method was developed for the selective removal of structure directing agent (SDA)/template from the functionalized SAPO-37.The complete removal of the SDA was evident according to FT-IR, TGA, 13C MAS-NMR and elemental analysis. The developed method was found to be efficient for removal of template from microporous molecular sieve viz., SAPO-37 and can be applied for other microporous molecular sieves such as SAPO-5, SAPO-40, etc. The powder XRD pattern of the template-removed samples showed a highly crystalline SAPO-37 phase. Argentometric titration revealed that more than 90% of diamine functionality exposed on the surface was accessible for catalytic applications. The resultant materials showed promising activity for ring opening of epoxide with aniline to yield β-amino-alcohol.

  14. Synthesis of cerium oxide catalysts supported on MCM-41 molecular sieve

    International Nuclear Information System (INIS)

    Souza, E.L.S.; Barros, T.R.B.; Sousa, B.V. de

    2016-01-01

    Porous materials have been widely studied as catalysts and catalyst support. The MCM-41 structure is the one that has been most studied because of its application possibilities in chemical processes. This work aimed to obtain and characterize cerium oxide catalysts supported on MCM-41 molecular sieve. The molecular sieve was synthesized by the conventional method with the following molar composition: 1 SiO2: 0.30 CTABr: NH3 11: 144 H2O. Then, 25% w/w cerium was incorporated into the MCM-41 using the wet impregnation process and the material obtained was activated by calcination. From the XRD patterns was confirmed the structure of the molecular sieve, and were identified the cerium oxide phases in its structure. The textural catalysts characteristics were investigated by isotherms of N2 adsorption/desorption (BET method). (author)

  15. Enrichment of ammonia concentration from aqua-ammonia vapors by using 3A molecular sieve

    International Nuclear Information System (INIS)

    Chiou, J.S.; Lin, T.M.; She, K.Y.; Chen, W.M.

    2009-01-01

    In aqua-ammonia refrigeration systems, the ammonia is the refrigerant and the water is the absorbent, the vapor produced in the generator always contains a small fraction of water. The removed of this residual water is a crucial issue in order to guarantee a reliable and efficient operation of these systems. Currently, the thermal distillation methods (via a rectifier and/or an analyzer) are used to further separate the water from aqua-ammonia mixtures. In this study, a molecular sieve module is used for ammonia purification. A thermal system with a 3A molecular sieve module was set up, and the conditions of working fluid entering into the sieve module is similar to that entering into the rectifier tower of a typical aqua-ammonia absorption system. Results from ammonia enrichment tests indicate the concentration of ammonia can be raised from about 80% up to about 99% if siever installation was properly arranged.

  16. In-line digital holography with phase-shifting Greek-ladder sieves

    Science.gov (United States)

    Xie, Jing; Zhang, Junyong; Zhang, Yanli; Zhou, Shenlei; Zhu, Jianqiang

    2018-04-01

    Phase shifting is the key technique in in-line digital holography, but traditional phase shifters have their own limitations in short wavelength regions. Here, phase-shifting Greek-ladder sieves with amplitude-only modulation are introduced into in-line digital holography, which are essentially a kind of diffraction lens with three-dimensional array diffraction-limited foci. In the in-line digital holographic experiment, we design two kinds of sieves by lithography and verify the validity of their phase-shifting function by measuring a 1951 U.S. Air Force resolution test target and three-dimensional array foci. With advantages of high resolving power, low cost, and no limitations at shorter wavelengths, phase-shifting Greek-ladder sieves have great potential in X-ray holography or biochemical microscopy for the next generation of synchrotron light sources.

  17. Use of thermal sieve to allow optical testing of cryogenic optical systems.

    Science.gov (United States)

    Kim, Dae Wook; Cai, Wenrui; Burge, James H

    2012-05-21

    Full aperture testing of large cryogenic optical systems has been impractical due to the difficulty of operating a large collimator at cryogenic temperatures. The Thermal Sieve solves this problem by acting as a thermal barrier between an ambient temperature collimator and the cryogenic system under test. The Thermal Sieve uses a set of thermally controlled baffles with array of holes that are lined up to pass the light from the collimator without degrading the wavefront, while attenuating the thermal background by nearly 4 orders of magnitude. This paper provides the theory behind the Thermal Sieve system, evaluates the optimization for its optical and thermal performance, and presents the design and analysis for a specific system.

  18. In-situ preparation of functionalized molecular sieve material and a methodology to remove template.

    Science.gov (United States)

    Yadav, Rekha; Ahmed, Maqsood; Singh, Arvind Kumar; Sakthivel, Ayyamperumal

    2016-03-10

    A series of diaminosilane-functionalized silicoaluminophosphate molecular sieve (SAPO-37) was prepared by in-situ synthesis, and a novel method was developed for the selective removal of structure directing agent (SDA)/template from the functionalized SAPO-37.The complete removal of the SDA was evident according to FT-IR, TGA, (13)C MAS-NMR and elemental analysis. The developed method was found to be efficient for removal of template from microporous molecular sieve viz., SAPO-37 and can be applied for other microporous molecular sieves such as SAPO-5, SAPO-40, etc. The powder XRD pattern of the template-removed samples showed a highly crystalline SAPO-37 phase. Argentometric titration revealed that more than 90% of diamine functionality exposed on the surface was accessible for catalytic applications. The resultant materials showed promising activity for ring opening of epoxide with aniline to yield β-amino-alcohol.

  19. Effect of soil sieving on respiration induced by low-molecular-weight substrates

    Science.gov (United States)

    Datta, Rahul; Vranová, Valerie; Pavelka, Marian; Rejšek, Klement; Formánek, Pavel

    2014-03-01

    The mesh size of sieves has a significant impact upon soil disturbance, affecting pore structure, fungal hyphae, proportion of fungi to bacteria, and organic matter fractions. The effects are dependent upon soil type and plant coverage. Sieving through a 2 mm mesh increases mineralization of exogenously supplied carbohydrates and phenolics compared to a 5 mm mesh and the effect is significant (p<0.05), especially in organic horizons, due to increased microbial metabolism and alteration of other soil properties. Finer mesh size particularly increases arabinose, mannose, galactose, ferulic and pthalic acid metabolism, whereas maltose mineralization is less affected. Sieving through a 5 mm mesh size is suggested for all type of experiments where enhanced mineralization of low-molecular-weight organic compounds needs to be minimalized.

  20. A systematic investigation of the preparation and properties of composite carbon molecular sieves containing inorganic oxides

    Science.gov (United States)

    Foley, Henry C.

    1990-01-01

    The objective of this research is to define the methodology for the preparation and characterization of new carbon-based molecular sieves with composite structures. Carbon molecular sieves have found increasing application in the field of separation and purification of gases. These materials are relatively easy to prepare and their surfaces can be modified to some extent. It is expected that by combining inorganic oxides with the carbonaceous structure one can begin to design composite materials with a wider range of possible chemical and physical properties. In this way, the IOM-CMS materials may confer distinct advantages over pure carbon molecular sieves, not just for separation, but also for catalysis. The most recent results in the design and characterization of these IOM-CMS materials are reviewed and summarized. Directions for further research are also presented.

  1. Live imaging of companion cells and sieve elements in Arabidopsis leaves.

    Directory of Open Access Journals (Sweden)

    Thibaud Cayla

    Full Text Available The phloem is a complex tissue composed of highly specialized cells with unique subcellular structures and a compact organization that is challenging to study in vivo at cellular resolution. We used confocal scanning laser microscopy and subcellular fluorescent markers in companion cells and sieve elements, for live imaging of the phloem in Arabidopsis leaves. This approach provided a simple framework for identifying phloem cell types unambiguously. It highlighted the compactness of the meshed network of organelles within companion cells. By contrast, within the sieve elements, unknown bodies were observed in association with the PP2-A1:GFP, GFP:RTM1 and RTM2:GFP markers at the cell periphery. The phloem lectin PP2-A1:GFP marker was found in the parietal ground matrix. Its location differed from that of the P-protein filaments, which were visualized with SEOR1:GFP and SEOR2:GFP. PP2-A1:GFP surrounded two types of bodies, one of which was identified as mitochondria. This location suggested that it was embedded within the sieve element clamps, specific structures that may fix the organelles to each another or to the plasma membrane in the sieve tubes. GFP:RTM1 was associated with a class of larger bodies, potentially corresponding to plastids. PP2-A1:GFP was soluble in the cytosol of immature sieve elements. The changes in its subcellular localization during differentiation provide an in vivo blueprint for monitoring this process. The subcellular features obtained with these companion cell and sieve element markers can be used as landmarks for exploring the organization and dynamics of phloem cells in vivo.

  2. Update on N2O4 Molecular Sieving with 3A Material at NASA/KSC

    Science.gov (United States)

    Davis, Chuck; Dorn, Claudia

    2000-01-01

    During its operational life, the Shuttle Program has experienced numerous failures in the Nitrogen Tetroxide (N2O4) portion of Reaction Control System (RCS), many of which were attributed to iron-nitrate contamination. Since the mid-1980's, N2O4 has been processed through a molecular sieve at the N2O4 manufacturer's facility which results in an iron content typically less than 0.5 parts-per-million-by-weight (ppmw). In February 1995, a Tiger Team was formed to attempt to resolve the iron nitrate problem. Eighteen specific actions were recommended as possibly reducing system failures. Those recommended actions include additional N2O4 molecular sieving at the Shuttle launch site. Testing at NASA White Sands Test Facility (WSTF) determined an alternative molecular sieve material could also reduce the water-equivalent content (free water and HNO3) and thereby further reduce the natural production of iron nitrate in N2O4 while stored in iron-alloy storage tanks. Since April '96, NASA Kennedy Space Center (KSC) has been processing N2O4 through the alternative molecular sieve material prior to delivery to Shuttle launch pad N2O4 storage tanks. A new, much larger capacity molecular sieve unit has also been used. This paper will evaluate the effectiveness of N2O4 molecular sieving on a large-scale basis and attempt to determine if the resultant lower-iron and lower-water content N2O4 maintains this new purity level in pad storage tanks and shuttle flight systems.

  3. Monopod bucket foundations under cyclic lateral loading

    DEFF Research Database (Denmark)

    Foglia, Aligi; Ibsen, Lars Bo

    on bucket foundations under lateral cyclic loading. The test setup is described in detail and a comprehensive experimental campaign is presented. The foundation is subjected to cyclic overturning moment, cyclic horizontal loading and constant vertical loading, acting on the same plane for thousands...

  4. 40 CFR 721.2120 - Cyclic amide.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Cyclic amide. 721.2120 Section 721... Cyclic amide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as a cyclic amide (PMN P-92-131) is subject to reporting under this section for the...

  5. Study on automatic control of high uranium concentration solvent extraction with pulse sieve-plate column

    International Nuclear Information System (INIS)

    You Wenzhi; Xing Guangxuan; Long Maoxiong; Zhang Jianmin; Zhou Qin; Chen Fuping; Ye Lingfeng

    1998-01-01

    The author mainly described the working condition of the automatic control system of high uranium concentration solvent extraction with pulse sieve-plate column on a large scale test. The use of the automatic instrument and meter, automatic control circuit, and the best feedback control point of the solvent extraction processing with pulse sieve-plate column are discussed in detail. The writers point out the success of this experiment on automation, also present some questions that should be cared for the automatic control, instruments and meters in production in the future

  6. Fast and accurate focusing analysis of large photon sieve using pinhole ring diffraction model.

    Science.gov (United States)

    Liu, Tao; Zhang, Xin; Wang, Lingjie; Wu, Yanxiong; Zhang, Jizhen; Qu, Hemeng

    2015-06-10

    In this paper, we developed a pinhole ring diffraction model for the focusing analysis of a large photon sieve. Instead of analyzing individual pinholes, we discuss the focusing of all of the pinholes in a single ring. An explicit equation for the diffracted field of individual pinhole ring has been proposed. We investigated the validity range of this generalized model and analytically describe the sufficient conditions for the validity of this pinhole ring diffraction model. A practical example and investigation reveals the high accuracy of the pinhole ring diffraction model. This simulation method could be used for fast and accurate focusing analysis of a large photon sieve.

  7. A case of radiation keratosis after sieve radiotherapy for cancer of the uterine cervix

    International Nuclear Information System (INIS)

    Imanaka, Kazufumi; Okuno, Takehiko; Tsuboi, Yoshitaka

    1981-01-01

    A case of radiation keratosis, regarded as the precancercerous state of the skin, is reported. A 54-year-old woman with cervical cancer was treated by postoperative sieve radiotherapy with 6,000 R as the tumor dose. Although free from cervical cancer, 10 years after this irradiation treatment, she was found to manifest multiple radiation keratosis coinciding with the pores of the sieve. We suggest that patients treated by irradiation for malignant diseases must be carefully followed for long periods, attending to not only the recurrence of the primary disease but also to radioinduced malignancy. (author)

  8. Case of radiation keratosis after sieve radiotherapy for cancer of the uterine cervix

    Energy Technology Data Exchange (ETDEWEB)

    Imanaka, K.; Okuno, T.; Tsuboi, Y. (Hyogo-Ken Cancer Center, Kobe (Japan)

    1981-12-01

    A case of radiation keratosis, regarded as the precancercerous state of the skin, is reported. A 54-year-old woman with cervical cancer was treated by postoperative sieve radiotherapy with 6,000 R as the tumor dose. Although free from cervical cancer, 10 years after this irradiation treatment, she was found to manifest multiple radiation keratosis coinciding with the pores of the sieve. We suggest that patients treated by irradiation for malignant diseases must be carefully followed for long periods, attending to not only the recurrence of the primary disease but also to radioinduced malignancy.

  9. Tritium recovery from helium purge stream of solid breeder blanket by cryogenic molecular sieve bed. 2. Regeneration operation of cryogenic molecular sieve bed

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Yoshinori; Enoeda, Mikio; Nishi, Masataka [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    Regeneration operation is a very important operation, because it is the most influential factor for deciding the net operation cycle time and the minimum dimension of Cryogenic Molecular Sieve Bed (CMSB). However, the experimental data of CMSB regeneration operation was not so sufficient that even the optimum regeneration procedure could not be decided yet. This work was focused on getting the primary information about various regeneration procedures. (author)

  10. Radiochemical and thermal studies of the copper(II)-exchanged form of synthetic zeolite linde sieve A

    International Nuclear Information System (INIS)

    Banerjee, S.P.

    1978-01-01

    Synthetic zeolite Linde Sieve A displays a double ion-sieve action. Only small cations can penetrate the single 6-rings into the beta cages. The radiochemical and thermal studies of copper(II)-exchanges form of 4A shows evidence of hydrated copper(II) ions in the zeolite structure. (author)

  11. Octahedral magnesium manganese oxide molecular sieves as the cathode material of aqueous rechargeable magnesium-ion battery

    International Nuclear Information System (INIS)

    Zhang, Hongyu; Ye, Ke; Shao, Shuangxi; Wang, Xin; Cheng, Kui; Xiao, Xue; Wang, Guiling; Cao, Dianxue

    2017-01-01

    Highlights: • The mico-sheet Mg-OMS-1 is synthesized by a simple hydrothermal method. • The mechanism of Mg 2+ insertion/deinsertion from Mg-OMS-1 is explored. • The electrode exhibits a good electrochemical performance in MgCl 2 electrolyte. - Abstract: Aqueous magnesium-ion batteries have shown the desired properties of high safety characteristics, similar electrochemical properties to lithium and low cost for energy storage applications. The micro-sheet morphology of todorokite-type magnesium manganese oxide molecular sieve (Mg-OMS-1) material, which applies as a novel cathode material for magnesium-ion battery, is obtained by the simple hydrothermal method. The structure and morphology of the particles are confirmed by X-ray power diffraction, X-ray photoelectron spectroscopy, inductively coupled plasma, scanning and transmission electron microscopy. The electrochemical performance of Mg-OMS-1 is researched by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and constant current charge-discharge measurement. Mg-OMS-1 shows a good battery behavior for Mg 2+ insertion and deinsertion in the aqueous electrolyte. When discharging at 10 mA g −1 in 0.2 mol dm −3 MgCl 2 aqueous electrolyte, the initial discharge capacity reaches 300 mAh g −1 . The specific capacity retention rate is 83.7% after cycling 300 times at 100 mA g −1 in 0.5 mol dm −3 MgCl 2 electrolyte with a columbic efficiency of nearly 100%.

  12. Historical Aspects in Tolerance Phenomenon Research

    Directory of Open Access Journals (Sweden)

    Janat A. Karmanova

    2013-01-01

    Full Text Available The article examines the historical aspect of the tolerance phenomenon research, particularly the study of tolerance in the age of Antiquity, Middle Ages, New Times, Enlightenment. It is remarkable that the problem of tolerance, emerged in Western civilization on religious grounds, laid the foundation for all other freedoms, attained in many countries. Besides, the article attaches special attention to the researchers of the East, such as Abu Nasr al-Farabi, Khoja Ahmed Yasawi, studies the historical aspect of works by Kazakhstan thinkers A. Kunanbayev, C. Valikhanova, K.B. Zharikbayev, S.K. Kaliyev, A.N. Nysanbayev, A.I. Artemev and others. The analysis of historical research of the tolerance phenomenon brings the author to the conclusion that religious freedom was the starting point for the emergence of new areas of tolerance display. The content of this phenomenon changed according to the historical peculiarities of the societies’ development

  13. Hysteresis phenomenon in nuclear reactor dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Pirayesh, Behnam; Pazirandeh, Ali [Islamic Azad Univ., Tehran (Iran, Islamic Republic of). Dept. of Nuclear Engineering, Science and Research Branch; Akbari, Monireh [Shahid Rajaee Teacher Training Univ., Tehran (Iran, Islamic Republic of). Dept. of Mathematics

    2017-05-15

    This paper applies a nonlinear analysis method to show that hysteresis phenomenon, due to the Saddle-node bifurcation, may occur in the nuclear reactor. This phenomenon may have significant effects on nuclear reactor dynamics and can even be the beginning of a nuclear reactor accident. A system of four dimensional nonlinear ordinary differential equations was considered to study the hysteresis phenomenon in a typical nuclear reactor. It should be noted that the reactivity was considered as a nonlinear function of state variables. The condition for emerging hysteresis was investigated using Routh-Hurwitz criterion and Sotomayor's theorem for saddle node bifurcation. A numerical analysis is also provided to illustrate the analytical results.

  14. Some Recent Developments in the Endochronic Theory with Application to Cyclic Histories

    Science.gov (United States)

    Valanis, K. C.; Lee, C. F.

    1983-01-01

    Constitutive equations with only two easily determined material constants predict the stress (strain) response of normalized mild steel to a variety of general strain (stress) histories, without a need for special unloading-reloading rules. The equations are derived from the endochronic theory of plasticity of isotropic materials with an intrinsic time scale defined in the plastic strain space. Agreement between theoretical predictions and experiments are are excellent quantitatively in cases of various uniaxial constant amplitude histories, variable uniaxial strain amplitude histories and cyclic relaxation. The cyclic ratcheting phenomenon is predicted by the present theory.

  15. Social Media: A Phenomenon to be Analyzed

    Directory of Open Access Journals (Sweden)

    danah boyd

    2015-04-01

    Full Text Available The phenomenon of “social media” has more to do with its cultural positioning than its technological affordances. Rooted in the broader “Web 2.0” landscape, social media helped engineers, entrepreneurs, and everyday people reimagine the role that technology could play in information dissemination, community development, and communication. While the technologies invoked by the phrase social media have a long history, what unfolded in the 2000s reconfigured socio-technical practices in significant ways. Reflecting on the brief history of social media, this essay argues for the need to better understand this phenomenon.

  16. Experiments for the Undergraduate Laboratory that Illustrate the Size-Exclusion Properties of Zeolite Molecular Sieves

    Science.gov (United States)

    Cooke, Jason; Henderson, Eric J.

    2009-01-01

    Experiments are presented that demonstrate the size-exclusion properties of zeolites and reveal the reason for naming zeolites "molecular sieves". If an IR spectrometer is available, the adsorption or exclusion of alcohols of varying sizes from dichloromethane or chloroform solutions can be readily demonstrated by monitoring changes in the…

  17. Application of Molecular Sieves in Transformations of Biomass and Biomass- Derived Feedstocks

    Czech Academy of Sciences Publication Activity Database

    Kubička, D.; Kubičková, I.; Čejka, Jiří

    2013-01-01

    Roč. 55, č. 1 (2013), s. 1-78 ISSN 0161-4940 R&D Projects: GA ČR GBP106/12/G015 Institutional support: RVO:61388955 Keywords : biomass * molecular sieves * zeolites Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 6.111, year: 2013

  18. Micro filtration membrane sieve with silicon micro machining for industrial and biomedical applications

    NARCIS (Netherlands)

    van Rijn, C.J.M.; Elwenspoek, Michael Curt

    1995-01-01

    With the use of silicon micromachining an inorganic membrane sieve for microfiltration is constructed, having a siliconnitride membrane layer with thickness typically 1 pm and perforations typically between 0.5 pm and 10 pm in diameter. As a support a -silicon wafer with openings of loo0 pm in

  19. Influence of incorporation method of sulfated zirconia in MCM-41 molecular sieve

    International Nuclear Information System (INIS)

    Pereira, C.E.; Santos, J.S.B.; Cavalcante, J.N.A.; Andrade, M.R.A.; Sousa, B.V.

    2016-01-01

    Sulfated metal oxides and sulfated zirconia have attracted great attention in recent years due to its high catalytic activity. The sulfated zirconia has the function of assigning the acidic material, through the formation of Bronsted acids and Lewis sites. The incorporation of sulfated zirconia in MCM-41 molecular sieve was carried out through the techniques: dry and wet. The wet process involves the use of an excess of solution on the volume of the support pores. Therefore, the concentration of the metal precursor on the support depends on the solution concentration and the pore volume of the support. In the process of incorporating by dry, the volume of the solution containing the precursor does not exceed the pore volume of the support. After either procedure, the impregnated support must be dried in order to allow the precursor compound can be converted into a catalytically active phase. This study aims to evaluate two methods of incorporation of sulfated zirconia in the mesoporous molecular sieve MCM-41. The process of merger took for wet and dry impregnation. Through the XRD patterns it was possible to identify the presence of the hexagonal structure of the molecular sieve, as well as the tetragonal and monoclinic phases of zirconia. From the spectroscopic analysis in the infrared region to the method the wet, it was possible to identify the vibrational frequencies related to the merger of sulfated zirconia in the MCM-41 structure of the molecular sieve. (author)

  20. Synthesis of Zeolite Nanomolecular Sieves of Different Si/Al Ratios

    Directory of Open Access Journals (Sweden)

    Pankaj Sharma

    2015-01-01

    Full Text Available Nanosized zeolite molecular sieves of different Si/Al ratios have been prepared using microwave hydrothermal reactor (MHR for their greater application in separation and catalytic science. The as-synthesized molecular sieves belong to four different type zeolite families: MFI (infinite and high silica, FAU (moderate silica, LTA (low silica and high alumina, and AFI (alumina rich and silica-free. The phase purity of molecular sieves has been assessed by X-ray diffraction (XRD analysis and morphological evaluation done by electron microscopy. Broad XRD peaks reveal that each zeolite molecular sieve sample is composed of nanocrystallites. Scanning electron microscopic images feature the notion that the incorporation of aluminum to MFI zeolite synthesis results in morphological change. The crystals of pure silica MFI zeolite (silicalite-1 have hexagon lump/disk-like shape, whereas MFI zeolite particles with Si/Al molar ratios 250 and 100 have distorted hexagonal lump/disk and pseudo spherical shapes, respectively. Furthermore, phase pure zeolite nanocrystals of octahedron (FAU, cubic (LTA, and rod (AFI shape have been synthesized. The average sizes of MFI, FAU, LTA, and AFI zeolite crystals are 250, 150, 50, and 3000 nm, respectively. Although the length of AFI zeolite rods is in micron scale, the thickness and width are of a few nanometers.

  1. The three-large-primes variant of the number field sieve

    NARCIS (Netherlands)

    S.H. Cavallar

    2002-01-01

    textabstractThe Number Field Sieve (NFS) is the asymptotically fastest known factoringalgorithm for large integers.This method was proposed by John Pollard in 1988. Sincethen several variants have been implemented with the objective of improving thesiever which is the most time consuming part of

  2. Importance of neutralization sieve analyses when seeking correlates of HIV-1 vaccine efficacy.

    Science.gov (United States)

    Montefiori, David C

    2014-01-01

    This commentary describes a rationale for the use of breakthrough viruses from clinical trial participants to assess neutralizing antibodies as a correlate of HIV-1 vaccine efficacy. The rationale is based on principles of a genetic sieve analysis, where the 2 analyses may be cooperative for delineating neutralizing antibodies as a mechanistic correlate of protection.

  3. An improved method for seed-bank analysis : Seedling emergence after removing the soil by sieving

    NARCIS (Netherlands)

    ter Heerdt, G.N.J.; Bekker, R.M.; Bakker, J.P.; Verweij, G.L.

    1. The seedling emergence method for assessing the size of the seed bank is improved by washing soil samples on a fine sieve and spreading the thus concentrated samples in a 3-5 mm thick layer on sterilized potting compost. 2. The method largely increases the number of seedlings that emerge as

  4. Effects of pricking, sun-drying and sieving on Ginger (Zingiber ...

    African Journals Online (AJOL)

    The effect of pricking, sun drying and sieving on the color retention of Nigerian yellow bark ginger were investigated. The exterior and interior surface of fresh, pricked and sun dried medium sized Nigerian ginger rhizomes (Tafin giwa) were analysed for colour variation. The colour values of the exterior surface of fresh ginger ...

  5. Hoveyda–Grubbs first generation type catalyst immobilized on mesoporous molecular sieves

    Czech Academy of Sciences Publication Activity Database

    Pastva, Jakub; Čejka, Jiří; Žilková, Naděžda; Mestek, O.; Rangus, M.; Balcar, Hynek

    2013-01-01

    Roč. 378, NOV 2013 (2013), s. 184-192 ISSN 1381-1169 R&D Projects: GA AV ČR IAA400400805 Institutional support: RVO:61388955 Keywords : Hoveyda–Grubbs type catalysts * Olefin metathesis * Mesoporous molecular sieves Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.679, year: 2013

  6. Effect of soil sieving on respiration induced by low-molecular-weight substrates

    Czech Academy of Sciences Publication Activity Database

    Datta, R.; Vranová, V.; Pavelka, Marian; Rejšek, K.; Formanek, P.

    2014-01-01

    Roč. 28, č. 1 (2014), s. 119-124 ISSN 0236-8722 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073; GA MŠk(CZ) LM2010007 Institutional support: RVO:67179843 Keywords : sieving * carbohydrates * phenolics * amino acids * microorganisms Subject RIV: EH - Ecology, Behaviour Impact factor: 1.117, year: 2014

  7. Synthesis and chemistry of chromium in CrAPO-5 molecular sieves

    NARCIS (Netherlands)

    Weckhuysen, B.M.; Schoonheydt, R.A.

    1994-01-01

    CrAPO-5 molecular sieves were synthesized hydrothermally starting with different Cr precursors and Cr and template contents. The behavior of Cr was investigated spectroscopically by diffuse reflectance spectroscopy (d.r.s.) and electron spin resonance (e.s.r.). In the gels, Cr 3+ and Cr 8+ are

  8. Carbon molecular sieve dense film membranes derived from Matrimid® for ethylene/ethane separation

    KAUST Repository

    Rungta, Meha; Xu, Liren; Koros, William J.

    2012-01-01

    Development of dense film carbon molecular sieve (CMS) membranes for ethylene/ethane (C 2H 4/C 2H 6) separation is reported. A commercial polyimide, Matrimid®, was pyrolyzed under vacuum and inert argon atmosphere, and the resultant CMS films were

  9. Oxygen isotopic fractionation of O₂ during adsorption and desorption processes using molecular sieve at low temperatures.

    Science.gov (United States)

    Ahn, Insu; Kusakabe, Minoru; Lee, Jong Ik

    2014-06-15

    Cryogenic trapping using molecular sieves is commonly used to collect O2 extracted from silicates for (17)O/(16)O and (18)O/(16)O analyses. However, gases which interfere with (17)O/(16)O analysis, notably NF3, are also trapped and their removal is essential for accurate direct measurement of the (17)O/(16)O ratio. It is also necessary to identify and quantify any isotopic fractionation associated with the use of cryogenic trapping using molecular sieves. The oxygen isotopic compositions of O2 before and after desorption from, and adsorption onto, 13X and 5A molecular sieves (MS13X and MS5A) at 0°C, -78°C, -114°C, and -130°C were measured in order to determine the oxygen isotopic fractionation at these temperatures. We also investigated whether isotopic fractionation occurred when O2 gas was transferred sequentially into a second cold finger, also containing molecular sieve. It was confirmed that significant oxygen isotopic fractionation occurs between the gaseous O2 and that adsorbed onto molecular sieve, if desorption and adsorption are incomplete. As the fraction of released or untrapped O2 becomes smaller with decreasing trapping temperature (from 0 to -130°C), the isotopic fractionation becomes larger. Approximately half of the total adsorbed O2 is released from the molecular sieve during desorption at -114°C, which is the temperature recommended for separation from NF3 (retained on the molecular sieve), and this will interfere with (17)O/(16)O measurements. The use of a single cold finger should be avoided, because partial desorption is accompanied by oxygen isotopic fractionation, thereby resulting in inaccurate isotopic data. The use of a dual cold finger arrangement is recommended because, as we have confirmed, the transfer of O2 from the first trap to the second is almost 100%. However, even under these conditions, a small isotopic fractionation (0.18 ± 0.05‰ in δ(17)O values and 0.26 ± 0.06‰ in δ(18)O values) occurred, with O2 in

  10. Aminopropyl-modified mesoporous molecular sieves as efficient adsorbents for removal of auxins

    International Nuclear Information System (INIS)

    Moritz, Michał; Geszke-Moritz, Małgorzata

    2015-01-01

    Graphical abstract: Adsorption of indole-3-acetic acid (IAA) on aminopropyl-modified mesoporous sieves. - Highlights: • Four types of mesoporous molecular sieves were used as sorbents for removal of auxins. • SBA-15, MCF, PHTS and SBA-16 were grafted with (3-aminopropyl)triethoxysilane. • The adsorption capacity of modified materials was higher as compared to pure silicas. • Surface modification and pore volume play important role in adsorption process. - Abstract: In the present study, mesoporous siliceous materials grafted with 3-aminopropyltriethoxysilane (APTES) were examined as sorbents for removal of chosen plant growth factors (auxins) such as 1-naphthaleneacetic acid (NAA), indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA). Four different types of mesoporous molecular sieves including SBA-15, PHTS, SBA-16 and MCF have been prepared via non-ionic surfactant-assisted soft templating method. Silica molecular sieves were thoroughly characterized by nitrogen adsorption–desorption analysis, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FT-IR). The maximum adsorption capacity (Q max ) for NAA, IAA and IBA was in the range from 51.0 to 140.8 mg/g and from 4.3 to 7.3 mg/g for aminopropyl-modified adsorbents and pure silicas, respectively. The best adsorption performance was observed for IAA entrapment using both APTES-functionalized SBA-15 and MCF matrices (Q max of 140.8 and 137.0 mg/g, respectively) which can be ascribed to their larger pore volumes and pore diameters. Moreover, these silicas were characterized by the highest adsorption efficiency exceeding 90% at low pollutant concentration. The experimental points for adsorption of plant growth factors onto aminopropyl-modified mesoporous molecular sieves fitted well to the Langmuir equation

  11. Aminopropyl-modified mesoporous molecular sieves as efficient adsorbents for removal of auxins

    Energy Technology Data Exchange (ETDEWEB)

    Moritz, Michał, E-mail: michal.moritz@put.poznan.pl [Poznan University of Technology, Faculty of Chemical Technology, Institute of Chemistry and Technical Electrochemistry, Berdychowo 4, 60-965 Poznań (Poland); Geszke-Moritz, Małgorzata, E-mail: Malgorzata.Geszke-Moritz@amu.edu.pl [NanoBioMedical Centre, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań (Poland)

    2015-03-15

    Graphical abstract: Adsorption of indole-3-acetic acid (IAA) on aminopropyl-modified mesoporous sieves. - Highlights: • Four types of mesoporous molecular sieves were used as sorbents for removal of auxins. • SBA-15, MCF, PHTS and SBA-16 were grafted with (3-aminopropyl)triethoxysilane. • The adsorption capacity of modified materials was higher as compared to pure silicas. • Surface modification and pore volume play important role in adsorption process. - Abstract: In the present study, mesoporous siliceous materials grafted with 3-aminopropyltriethoxysilane (APTES) were examined as sorbents for removal of chosen plant growth factors (auxins) such as 1-naphthaleneacetic acid (NAA), indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA). Four different types of mesoporous molecular sieves including SBA-15, PHTS, SBA-16 and MCF have been prepared via non-ionic surfactant-assisted soft templating method. Silica molecular sieves were thoroughly characterized by nitrogen adsorption–desorption analysis, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FT-IR). The maximum adsorption capacity (Q{sub max}) for NAA, IAA and IBA was in the range from 51.0 to 140.8 mg/g and from 4.3 to 7.3 mg/g for aminopropyl-modified adsorbents and pure silicas, respectively. The best adsorption performance was observed for IAA entrapment using both APTES-functionalized SBA-15 and MCF matrices (Q{sub max} of 140.8 and 137.0 mg/g, respectively) which can be ascribed to their larger pore volumes and pore diameters. Moreover, these silicas were characterized by the highest adsorption efficiency exceeding 90% at low pollutant concentration. The experimental points for adsorption of plant growth factors onto aminopropyl-modified mesoporous molecular sieves fitted well to the Langmuir equation.

  12. Preliminary Design of Molecular Sieve for Removing Organic Iodide in Containment Filtered Venting System

    Energy Technology Data Exchange (ETDEWEB)

    Park, Tong Kyu; Shin, So Eun; Lee, Byung Chul [Heungdeok IT Valley Bldg., Yongin (Korea, Republic of); Kim, Hong Hyun; Lee, Kyung Jun [Gemvax and KAEL Inc., Daejeon (Korea, Republic of)

    2014-05-15

    In this paper, to increase the DF for gaseous iodine species, especially organic iodide, molecular sieve filled by silver exchanged zeolites is proposed and designed preliminarily. Its aerodynamic analysis is also performed and presented. In order to increase the DF for gaseous organic iodide, deep-bed type molecular sieve was proposed and designed preliminarily. Total 1,620kg of silver exchanged zeolites were filled evenly in 10 beds of the molecular sieve. The safety factor in the case of 20m{sup 3}/s will be smaller than the counterpart of the standard case (6m{sup 3}/s). However, if the adsorption capacity of the zeolites is larger than 3.09mg/g when the residence time is 0.09 second, the designed molecular sieve can be used at 20m3/s of volumetric flow rate. The removal efficiency for organic iodide should be considered as well as economical aspects in the design of molecular sieve. In the event of nuclear power plant (NPP) severe accident, the nuclear reactor containment might suffer damage resulting from overpressure caused by decay heat. In order to prevent this containment damage, containment venting has been considered as one of effective methods. However, since vented gases contain radioactive fission products, they should be filtered to be released to environment. Generally, containment filtered venting system (CFVS) is installed on NPP to achieve this aim. Even though great amount of efforts have been devoted to developing the CFVS using various filtering methods, the decontaminant factor (DF) for radioactive gaseous iodide is still unsatisfactory while DFs for radioactive aerosols and elemental iodine are very high.

  13. Mesoscale Phenomenon Revealed by an Acoustic Sounder

    DEFF Research Database (Denmark)

    Lundtang Petersen, Erik; Jensen, Niels Otto

    1976-01-01

    A particular phenomenon observed on an acoustic sounder record is analyzed, and is interpreted as being associated with the passing of a land breeze front. A simple physical explanation of the frontal movements is suggested. The actual existence of the land breeze is demonstrated by examination...

  14. Methods to Minimize Zero-Missing Phenomenon

    DEFF Research Database (Denmark)

    da Silva, Filipe Miguel Faria; Bak, Claus Leth; Gudmundsdottir, Unnur Stella

    2010-01-01

    With the increasing use of high-voltage AC cables at transmission levels, phenomena such as current zero-missing start to appear more often in transmission systems. Zero-missing phenomenon can occur when energizing cable lines with shunt reactors. This may considerably delay the opening of the ci...

  15. Key-Phenomenon and Religious Meaning

    Directory of Open Access Journals (Sweden)

    Lomuscio Vincenzo

    2017-09-01

    Full Text Available In this paper I develop a phenomenology of religious experience through the notion of keyphenomenon. My analysis moves from a general phenomenology of situation, in which we have to relate different phenomena according to a sense. What does “according to a sense” mean? My suggestion is that we should look for a relationship among these data when we find a key-phenomenon (among a series of phenomena that would enlighten all the others. This key-phenomenon would show a non-phenomenal meaning which would make all the others understandable. Each other datum, therefore, becomes the witness of invisible meaning through a key-witness. The key-phenomenon we choose determines the role (i.e., the truth of each datum within its situation. This phenomenological relationship belongs to both the sense of day-life situations, and that one of possible religious situations. If the religious interpretation of a situation depends on our choice of key-phenomenon, or key-witness, we have to define what kind of keyphenomenon constitutes a religious intuition.

  16. Concept "Medical Museum" as a Sociocultural Phenomenon

    Science.gov (United States)

    Chizh, Nina V.; Slyshkin, Gennady G.; Zheltukhina, Marina R.; Privalova, Irina V.; Kravchenko, Olga A.

    2016-01-01

    The article examines the concept "medical museum" as a sociocultural phenomenon. The register of medical museums in Russia makes the material of research. The complex methods of analysis of the concept "medical museum" are used. The philosophical, historical, cultural, structural, communicative and semantic analysis is carried…

  17. Geometrical optics and the diffraction phenomenon

    International Nuclear Information System (INIS)

    Timofeev, Aleksandr V

    2005-01-01

    This note outlines the principles of the geometrical optics of inhomogeneous waves whose description necessitates the use of complex values of the wave vector. Generalizing geometrical optics to inhomogeneous waves permits including in its scope the analysis of the diffraction phenomenon. (methodological notes)

  18. Laser Sintering Technology and Balling Phenomenon.

    Science.gov (United States)

    Oyar, Perihan

    2018-02-01

    The aim of this review was to evaluate the balling phenomenon which occurs typically in Selective Laser Sintering (SLS). The balling phenomenon is a typical SLS defect, and observed in laser sintered powder, significantly reduces the quality of SLS, and hinders the further development of SLS Technology. Electronic database searches were performed using Google Scholar. The keywords "laser sintering, selective laser sintering, direct metal laser melting, and balling phenomenon" were searched in title/abstract of publications, limited to December 31, 2016. The inclusion criteria were SLS, balling phenomenon, some alloys (such as Cr-Co, iron, stainless steel, and Cu-based alloys) mechanical properties, microstructure and bond strength between metal-ceramic crown, laboratory studies, full text, and in English language. A total of 100 articles were found the initial search and yielded a total of 50 studies, 30 of which did not fulfill the inclusion criteria and were therefore excluded. In addition, 20 studies were found by screening the reference list of all included publications. Finally, 40 studies were selected for this review. The method in question is regulated by powder material characteristics and the conditions of laser processing. The procedure of formation, affecting factors, and the mechanism of the balling effect are very complex.

  19. Orgasm Induced Seizures: A Rare Phenomenon

    African Journals Online (AJOL)

    testing of the brain revealed no structural abnormality. His blood examination findings were ... A variety of stimuli can cause reflex seizures, Some triggers include light, music and cognitive phenomenon. There are case reports ... seizures cause great personal distress and significantly affect marital relationships. Though ...

  20. On charge-3 cyclic monopoles

    International Nuclear Information System (INIS)

    Braden, H W; D'Avanzo, Antonella; Enolski, V Z

    2011-01-01

    We determine the spectral curve of charge-3 BPS su(2) monopoles with C 3 cyclic symmetry. The symmetry means that the genus 4 spectral curve covers a (Toda) spectral curve of genus 2. A well adapted homology basis is presented enabling the theta functions and monopole data of the genus 4 curve to be given in terms of genus 2 data. The Richelot correspondence, a generalization of the arithmetic mean, is used to solve for this genus 2 curve. Results of other approaches are compared

  1. On numerically pluricanonical cyclic coverings

    International Nuclear Information System (INIS)

    Kulikov, V S; Kharlamov, V M

    2014-01-01

    We investigate some properties of cyclic coverings f:Y→X (where X is a complex surface of general type) branched along smooth curves B⊂X that are numerically equivalent to a multiple of the canonical class of X. Our main results concern coverings of surfaces of general type with p g =0 and Miyaoka-Yau surfaces. In particular, such coverings provide new examples of multi-component moduli spaces of surfaces with given Chern numbers and new examples of surfaces that are not deformation equivalent to their complex conjugates

  2. Cyclic graphs and Apery's theorem

    International Nuclear Information System (INIS)

    Sorokin, V N

    2002-01-01

    This is a survey of results about the behaviour of Hermite-Pade approximants for graphs of Markov functions, and a survey of interpolation problems leading to Apery's result about the irrationality of the value ζ(3) of the Riemann zeta function. The first example is given of a cyclic graph for which the Hermite-Pade problem leads to Apery's theorem. Explicit formulae for solutions are obtained, namely, Rodrigues' formulae and integral representations. The asymptotic behaviour of the approximants is studied, and recurrence formulae are found

  3. A system for cyclical voltametry

    International Nuclear Information System (INIS)

    Silva, R.P. da; Chierice, G.O.

    1974-01-01

    The constrution of a system composed by two instruments, voltametric circuit and potenciostate is depicted. Both instruments junction joined so that the voltametric circuit works as a triangular pulse generator, capable of operating with independent ascendant and descendant slope change, with unique pulse of continuous regime. The circuit of the potenciostate is composed of an amplifier with high entrance impedance and capable of supplying relatively high currents at the exit. The equipment was tested to study the aqueous Pb 2+ system in mercury electrode. this system depicted for the cyclical-voltometry technique set in use at I.E.A., Sao Paulo (Brazil), has very good linearity

  4. Cyclic AMP in rat pancreatic islets

    International Nuclear Information System (INIS)

    Grill, V.; Borglund, E.; Cerasi, E.; Uppsala Univ.

    1977-01-01

    The incorporation of [ 3 H]adenine into cyclic AMP was studied in rat pancreatic islets under varying conditions of labeling. Prolonging the exposure to [ 3 H]adenine progressively augmented the islet cyclic [ 3 H]AMP level. Islets labeled for different periods of time and subsequently incubated (without adenine) in the presence of D-glucose or cholera toxin showed stimulations of intra-islet cyclic [ 3 H]AMP that were proportionate to the levels of radioactive nucleotide present under non-stimulatory conditions. Labeling the islets in a high glucose concentration (27.7 mM) did not modify the nucleotide responses to glucose or cholera toxin. The specific activity of cyclic [ 3 H]AMP, determined by simultaneous assay of cyclic [ 3 H]AMP and total cyclic AMP, was not influenced by glucose or cholera toxin. Glucose had no effect on the specific activity of labeled ATP

  5. Plasma-focused cyclic accelerators

    International Nuclear Information System (INIS)

    Mondelli, A.A.; Chernin, D.P.

    1985-01-01

    The use of ambient plasma to neutralize the transverse forces of an intense particle beam has been known for many years. Most recently, the so-called ion-focused regime (IFR) for beam propagation has been used as a means of focusing intense electron beams in linear accelerators and suggested for injecting an electron beam across magnetic field lines into a high-current cyclic accelerator. One technique for generating the required background plasma for IFR propagation is to use a laser to ionize ambient gas in the accelerator chamber. For cyclic accelerators a technique is required for carrying the plasma channel and the beam around a bend. Multiple laser-generated channels with dipole magnetic fields to switch the beam from one channel to the next have been tested at Sandia. This paper discusses an alternative means of plasma production for IFR, viz. by using rf breakdown. For this approach the accelerator chamber acts as a waveguide. With a suitable driving frequency, a waveguide mode can be driven which has its peak field intensity on the axis with negligible fields at the chamber walls. The plasma production and hence the beam propagation is thereby isolated from the walls. This technique is not limited to toroidal accelerators. It may be applied to any accelerator or recirculator geometry as well as for beam steering and for injection or extraction of beams in closed accelerator configurations

  6. Cyclic Vomiting Syndrome in Children

    Directory of Open Access Journals (Sweden)

    T.V. Sorokman

    2016-08-01

    Full Text Available Introduction. Cyclic vomiting syndrome (CVS — is a fairly common disease of unknown etiology that affects children of all age groups and sometimes adult population and refers to the functional disorders of the gastrointestinal tract. Objective: to evaluate the effectiveness of the usage of Rehydron Optim for oral rehydration therapy in children. Materials and methods. The treatment of 40 children aged 3 to 11 years with CVS (15 persons and primary acetonemic syndrome (25 persons in the period of acetonemic crisis, including 15 boys and 25 girls, was analyzed. All children were observed in the outpatient department of the Regional children’s hospital of Chernivtsi. Diagnosis was established based on anamnesis, clinical and laboratory data. Patients underwent required clinico-biological tests and instrumental examinations. The dynamics of the following syndromes was investigated: pain, vomiting, dehydration and intoxication. Rehydration therapy in all cases was oral with the usage of Rehydron Optim. Results of the study and their discussion. A cyclical vomiting was observed in children with primary acetonemic syndrome with satisfactory condition in attack-free period. Migraine-like headaches prevailed in 36 patients (80 %, and the age of these patients was older than 7 years. Same children had episodes of paroxysmal autonomic failure. Almost all surveyed children had in their family history the risk factors for CVS development. All children had positive dynamics of the main basic clinical manifestations on the background of oral rehydration therapy using Rehydron Optim. Within the 1st day of oral rehydration therapy with Rehydron Optim in children, we have noted a significant decrease in the incidence of lethargy, vomiting, spastic abdominal pain, smell of acetone in the exhaled air (p < 0.05. In children with the I degree of dehydration, clinical signs of dehydration were not seen before the treatment, and children with the II degree had an

  7. [Cyclic Cushing's Syndrome - rare or rarely recognized].

    Science.gov (United States)

    Kiałka, Marta; Doroszewska, Katarzyna; Mrozińska, Sandra; Milewicz, Tomasz; Stochmal, Ewa

    2015-01-01

    Cyclic Cushing's syndrome is a type of Cushing's disease which is characterized by alternating periods of increasing and decreasing levels of cortisol in the blood. The diagnostic criteria for cyclic Cushing's syndrome are at least three periods of hypercortisolism alternating with at least two episodes of normal levels of serum cortisol concentration. The epidemiology, signs, symptoms, pathogenesis and treatment of cyclic Cushing's syndrome have been discussed.

  8. Phase transition phenomenon: A compound measure analysis

    Science.gov (United States)

    Kang, Bo Soo; Park, Chanhi; Ryu, Doojin; Song, Wonho

    2015-06-01

    This study investigates the well-documented phenomenon of phase transition in financial markets using combined information from both return and volume changes within short time intervals. We suggest a new measure for the phase transition behaviour of markets, calculated as a return distribution conditional on local variance in volume imbalance, and show that this measure successfully captures phase transition behaviour under various conditions. We analyse the intraday trade and quote dataset from the KOSPI 200 index futures, which includes detailed information on the original order size and the type of each initiating investor. We find that among these two competing factors, the submitted order size yields more explanatory power on the phenomenon of market phase transition than the investor type.

  9. The veining phenomenon in unalloyed plutonium

    International Nuclear Information System (INIS)

    White, J.S.

    1976-01-01

    An investigation has been made of the veining phenomenon in unalloyed plutonium. The surface markings, or veins, which are sometimes seen on α-phase plutonium samples, arise as a result of the β→α transformation. As far as is known, this veining is unrivalled in its scale and form as compared with the solid state surface transformation effects shown by any other metal. The phenomenon has been explained by the application of the Le Chatelier principle to the phase change. In this instance, the large (10%) volume contraction associated with the β→α reaction and the anisotropy of the nonoclinic α-phase structure, account for the fact that the veins are so prominent in plutonium. On the basis of the proposed model, the veins can only form at temperatures where the transformation mechanism is non-martensitic. (Auth.)

  10. Diffusion phenomenon for linear dissipative wave equations

    KAUST Repository

    Said-Houari, Belkacem

    2012-01-01

    In this paper we prove the diffusion phenomenon for the linear wave equation. To derive the diffusion phenomenon, a new method is used. In fact, for initial data in some weighted spaces, we prove that for {equation presented} decays with the rate {equation presented} [0,1] faster than that of either u or v, where u is the solution of the linear wave equation with initial data {equation presented} [0,1], and v is the solution of the related heat equation with initial data v 0 = u 0 + u 1. This result improves the result in H. Yang and A. Milani [Bull. Sci. Math. 124 (2000), 415-433] in the sense that, under the above restriction on the initial data, the decay rate given in that paper can be improved by t -γ/2. © European Mathematical Society.

  11. Modeling Cyclic Variation of Intracranial Pressure

    National Research Council Canada - National Science Library

    Daley, M

    2001-01-01

    ...) recording during mechanical ventilation are due to cyclic extravascular compressional modulation primarily of the cerebral venous bed, an established isovolumetric model of cerebrospinal fluid...

  12. Behaviour of Cohesionless Soils During Cyclic Loading

    DEFF Research Database (Denmark)

    Shajarati, Amir; Sørensen, Kris Wessel; Nielsen, Søren Kjær

    Offshore wind turbine foundations are typically subjected to cyclic loading from both wind and waves, which can lead to unacceptable deformations in the soil. However, no generally accepted standardised method is currently available, when accounting for cyclic loading during the design of offshore...... wind turbine foundations. Therefore a literature study is performed in order to investigate existing research treating the behaviour of cohesionless soils, when subjected to cyclic loading. The behaviour of a soil subjected to cyclic loading is found to be dependent on; the relative density, mean...

  13. Cyclical subnormal separation in A-groups

    International Nuclear Information System (INIS)

    Makarfi, M.U.

    1995-12-01

    Three main results, concerning A-groups in respect of cyclical subnormal separation as defined in, are presented. It is shown in theorem A that any A-group that is generated by elements of prime order and satisfying the cyclical subnormal separation conditions is metabelian. The two other main results give necessary and sufficient conditions for A-groups, that are split extensions of certain abelian p-groups by a metabelian p'-group, to satisfy the cyclical subnormal separation condition. There is also a result which shows that A-groups with elementary abelian Sylow subgroups are cyclically separated as defined. (author). 7 refs

  14. Phenomenon of displacement in Arabic language

    Directory of Open Access Journals (Sweden)

    2015-09-01

    Full Text Available Displacement is one of the characteristics of language and common phenomena in the Arabic language. Not only is this phenomenon limited to Arabic poetry and prose, but it is also broadened, so we can see examples of this in the Qur'an. Because of this phenomenon extensively in Arabic literature and also because of its essence that leads to the transmission of the elements for the first visibility to the other visibility in the sentence and sometimes had to change the grammatical role of the words, its identify helps us in a better understanding of text and the correct translation of it and protects the reader from mistakes. This paper in the descriptive analytical approach tries studying of the phenomenon of the displacement in the Arabic language and bringing its instances in Arabic poetry and prose as well as verses contained in the Holy Quran, to show that through the types and characteristics in the Arabic language and to response to several questions, including: how important is the displacement and what is its types in rhetoric, and the reasons of the displacement, and etc... Of the most important results of this study may refer to the undeniable role of the displacement as a rhetorical method to better understanding of the texts including: one of the most important reasons of the displacement in the use of language is to improve speech verbally and morally, and violation of the standard language and create a poetic atmosphere, and the recognition of the occurrence of the phenomenon of displacement in the Arabic language that uphold different interpretations remote and estimates when faced with the displacement in the text and help us to understand it and etc...

  15. Multiplayer computer games as youth's leisure phenomenon

    OpenAIRE

    HADERKOVÁ, Barbora

    2016-01-01

    The thesis is dedicated to multiplayer computer games as youth's leisure phenomenon of this time. The theoretical part is focused on computer games history, multiplayer computer games and their types, gaming platforms, community of multiplayer games players and potential negatives and positives, which follows from playing this type of games. The practical part contains a qualitative survey using interviews with multiplayer computer games players aged from 15 to 26 years from city of České Bud...

  16. THE PHENOMENON OF MIGRATION. OPPORTUNITIES AND CHALLENGES

    Directory of Open Access Journals (Sweden)

    Carmen BOGHEAN

    2016-07-01

    Full Text Available Migration is not a new phenomenon, neither for Europe, nor for the entire world and it exists since the beginning of mankind. Over time, this kind of international mobility generated many opportunities, but many challenges as well. Being an extremely important and complex phenomenon, both in economic terms and mostly from the social perspective, mass emigration has never been more intense as nowadays. Together with this particular complexity, the intensity of the migration phenomenon reveals each individual’s profound freedom desire, but also the acute need to ensure a better future for himself and especially for his family. Currently, an ever increasing number of individuals migrate in search of a better place, changing regions, countries or even continents. Witnessing the events that transcend the people all around the world, we consider that migration generates economic, social and cultural, but also political profound changes. These major changes require the involvement of the political actors, namely the governments, in creating a favorable and reliable framework so as the society and decision makers to understand that immigrants represent an opportunity for the emerging economies and not a phenomenon that should be criticized. In this paper we aim to follow the theories regarding the migration process, as well as the changes it generates, taking into consideration that of the 507 million current inhabitants of the EU, approximately 20 million are from countries outside the EU. We consider this research to be underlain, taking into consideration that regardless of the form it takes, in Europe immigration is and will remain a difficult to manage reality.

  17. An order-by-disorder process in the cyclic phase of spin-2 condensate with a weak magnetic field

    International Nuclear Information System (INIS)

    Zheng, Gong-Ping; Xu, Lei-Kuan; Qin, Shuai-Feng; Jian, Wen-Tian; Liang, J.-Q.

    2013-01-01

    We present in this paper a model study on the “order-by-disorder” process in the cyclic phase of spin-2 condensate, which forms a family of incommensurable, spiral degenerate ground states. On the basis of the ordering mechanism of entropic splitting, it is demonstrated that the energy corrections resulting from quantum fluctuations of disorder lift the accidental degeneracy of the cyclic configurations and thus lead to an eventual spiral order called the cyclic order. The order-by-disorder phenomenon is then realized even if the magnetic field exists. Finally, we show that our theoretic observations can be verified experimentally by direct detection of the cyclic order in the 87 Rb condensate of a spin-2 manifold with a weak magnetic field. -- Highlights: •A model for the order-by-disorder process in the cyclic phase of spin-2 condensate is presented. •The second-order quantum fluctuations of the mean-field states are studied. •The energy corrections lift the accidental degeneracy of the cyclic configurations. •The order-by-disorder phenomenon is realized even if a magnetic field exists. •The theoretic observations can be verified experimentally for 87 Rb condensate

  18. Sieve-based relation extraction of gene regulatory networks from biological literature.

    Science.gov (United States)

    Žitnik, Slavko; Žitnik, Marinka; Zupan, Blaž; Bajec, Marko

    2015-01-01

    Relation extraction is an essential procedure in literature mining. It focuses on extracting semantic relations between parts of text, called mentions. Biomedical literature includes an enormous amount of textual descriptions of biological entities, their interactions and results of related experiments. To extract them in an explicit, computer readable format, these relations were at first extracted manually from databases. Manual curation was later replaced with automatic or semi-automatic tools with natural language processing capabilities. The current challenge is the development of information extraction procedures that can directly infer more complex relational structures, such as gene regulatory networks. We develop a computational approach for extraction of gene regulatory networks from textual data. Our method is designed as a sieve-based system and uses linear-chain conditional random fields and rules for relation extraction. With this method we successfully extracted the sporulation gene regulation network in the bacterium Bacillus subtilis for the information extraction challenge at the BioNLP 2013 conference. To enable extraction of distant relations using first-order models, we transform the data into skip-mention sequences. We infer multiple models, each of which is able to extract different relationship types. Following the shared task, we conducted additional analysis using different system settings that resulted in reducing the reconstruction error of bacterial sporulation network from 0.73 to 0.68, measured as the slot error rate between the predicted and the reference network. We observe that all relation extraction sieves contribute to the predictive performance of the proposed approach. Also, features constructed by considering mention words and their prefixes and suffixes are the most important features for higher accuracy of extraction. Analysis of distances between different mention types in the text shows that our choice of transforming

  19. Plastic strain accumulation during asymmetric cyclic loading of Zircaloy-2 at room temperature

    International Nuclear Information System (INIS)

    Rajpurohit, R.S.; Santhi Srinivas, N.C.; Singh, Vakil

    2016-01-01

    Asymmetric cyclic loading leads to accumulation of cyclic plastic strain and reduces the fatigue life of components. This phenomenon is known as ratcheting fatigue. Zircaloy-2 is a important structural material in nuclear reactors and used as pressure tubes and fuel cladding in pressurized light and heavy water nuclear reactors. Due to power fluctuations, these components experience plastic strain cycles in the reactor and their life is reduced due to strain cycles. Power fluctuations also cause asymmetric straining of the material and leads to accumulation of plastic strain. The present investigation deals with the effect of the magnitude of mean stress, stress amplitude and stress rate on hardening/softening behavior of Zircaloy-2 under asymmetric cyclic loading, at room temperature. It was observed that plastic strain accumulation increased with mean stress and stress amplitude; however, it decreased with stress rate. (author)

  20. Random cyclic constitutive models of 0Cr18Ni10Ti pipe steel

    International Nuclear Information System (INIS)

    Zhao Yongxiang; Yang Bing

    2004-01-01

    Experimental study is performed on the random cyclic constitutive relations of a new pipe stainless steel, 0Cr18Ni10Ti, by an incremental strain-controlled fatigue test. In the test, it is verified that the random cyclic constitutive relations, like the wide recognized random cyclic strain-life relations, is an intrinsic fatigue phenomenon of engineering materials. Extrapolating the previous work by Zhao et al, probability-based constitutive models are constructed, respectively, on the bases of Ramberg-Osgood equation and its modified form. Scattering regularity and amount of the test data are taken into account. The models consist of the survival probability-strain-life curves, the confidence strain-life curves, and the survival probability-confidence-strain-life curves. Availability and feasibility of the models have been indicated by analysis of the present test data

  1. Phenomenon of political actionism in modern society

    Directory of Open Access Journals (Sweden)

    V. M. Bavykina

    2016-08-01

    Full Text Available Political actionism is the fenomen in social and art space, that appeared in middle of XX century as the practice of critic and protest with using different artistic methods and techniques. Political actionism as art and political tradition exist in postsoviet space, especially in Russia where actionism appeared in 1990 years and develops for actually days. In other countries this phenomenon not such systematic.  But analyze and compare actions in different countries appears the possibility to understand social and cultural context, their difference and similarity. Actionism is a reaction to external public, social and political situation, but its appearance more like the symptom of some problem than its critic or display – traditional approaches in art.  Appearance of actionism also connected with inability of manifestation of personal and civil liberty, that’s why in actions liberty affairs in such radical and hyperbolized forms. First volume of Russian political actionism began in 1990 years (Oleg Kulik, Alexander Brener, Anatoly Osmolovsky etc. and Second volume in 2010 (art-group Voina, Pussy Riot, Pyotr Pavlensky. This process not only a transformation of artistic and traditional space, but also modification of reaction on social and political situation. Actionism becomes a source of new type of knowledge, that give a possibility to see the habitual reality from another side and find in it new pointes and concepts. Political actionism contracting own interpretation of already well-established phenomenon. Usual concepts of liberty, authority, social control are deconstructed in actions. Those destructions of reality and cultural reorientation destroys traditional imposed patterns of interaction and social structure. But new views, that appeared in daily life from actions, often has mistaken interpretations. Exist a problem about identification of actions, its correct interpretations and understanding of its causes. In article was

  2. Long-term fashion forecast based on the sociological model of cyclic changes

    Directory of Open Access Journals (Sweden)

    А V Lebsak-Kleimans

    2010-09-01

    Full Text Available The concepts of social changes coined by classical sociology may be incorporated as the basis for the elaboration of social prognostication models which, in turn, may suitable for fashion forecast applied technologies development. In the framework of the given paper fashion is described as the phenomenon of collective behaviour. The principles of long-term fashion trends forecast are shown to be in line with the concepts of cyclic development.

  3. Plasma-focused cyclic accelerators

    International Nuclear Information System (INIS)

    Mondelli, A.A.; Chernin, D.P.

    1985-01-01

    The use of ambient plasma to neutralize the transverse forces of an intense particle beam has been known for many years. Most recently, the so-called ion-focused regime (IFR) for beam propagation has been used as a means of focusing intense electron beams in linear accelerators and suggested for injecting an electron beam across magnetic field lines into a high-current cyclic accelerator. One technique for generating the required background plasma for IFR propagation is to use a laser to ionize ambient gas in the accelerator chamber. This paper discusses an alternative means of plasma production for IFR, viz. by using RF breakdown. For this approach the accelerator chamber acts as a waveguide. This technique is not limited to toroidal accelerators. It may be applied to any accelerator or recirculator geometry as well as for beam steering and for injection or extraction of beams in closed accelerator configurations

  4. Flooding characteristics of pulsed-sieve plate column. Contributed Paper ED-09

    International Nuclear Information System (INIS)

    Vishnu Anand, P.; Pandey, N.K.; Rajeev, R.; Joyakin, C.V.; Kamachi Mudali, U.; Natarajan, R.

    2014-01-01

    Successful design of a pulsed sieve plate extraction column relies on profound understanding of its hydrodynamic and mass transfer characteristics. Present work outlines a comprehensive study of flooding velocity, a hydrodynamic parameter, as a function of various operating conditions of the column. Experimental studies were carried out using water-normal paraffin hydrocarbon system, under no mass transfer condition, in a pilot plant pulsed sieve plate column equipped with standard plate cartridges. Flooding velocity is characterized here as a function of phase flow ratio and pulse velocity with the aid of characteristic velocity concept together with an exponential function. Flooding points were experimentally identified with satisfactory accuracy using a quantitative method and dispersed phase hold-up was measured by online sampling. To verify the extent of applicability of some of the reported generalized flooding correlations from a design perspective, an analysis was done using our precisely generated experimental flooding data. (author)

  5. Sieving of municipal solid waste incineration (MSWI) bottom ash; Siktning av askor fraan avfallsfoerbraenning

    Energy Technology Data Exchange (ETDEWEB)

    Todorovic, Jelena

    2010-07-01

    Waste-to-Energy is steadily increasing in Sweden and more than 46 % of municipal solid waste (MSW) is being incinerated. Solid residues from MSW incineration (MSWI) mainly constitute of bottom ash and air pollution control (APC) residues. Bottom ashes from MSWI amounted to 0.7 millions of tons and APC residues to 0.2 millions of tons in 2008. Bottom ashes from MSWI contain pollutants like metals (e.g. Pb, Zn, Cu), metalloids (e.g. As, Se), elements forming oxyanions (e.g. Sb, Cr, Mo) and easily soluble salts like chlorides and sulphates. These constituents can leach out polluting the environment if ash comes in contact with water. Treatment methods for decreasing the amount of pollutants in ashes or their mobility are therefore needed. Sieving was investigated as a separate or a complementary treatment method for MSWI ashes. Hypothesis was that the large share of pollutant concentrations could be removed from the ashes through separation of the finest fractions. The rest is less harmful to the environment, more acceptable as secondary construction material or less costly to landfill. Investigation included three MSWI ashes, namely bottom ash from Boraas Energy och Miljoe's plant with fluid bad, boiler ash from the same plant and bottom ash from Renova's stocker grate type plant. Ashes were sieved in 2-4 size fractions. Total content of pollutants and their leachability (batch leaching test, L/S=10 l/kg) was assessed for each of the fractions. Leaching results were compared to limit values stipulated by Swedish Environmental Protection Agency for acceptance of waste at landfills as wells as to recommendations for reuse of waste as a construction material. Results from bottom ash from the stocker grate type incinerator and from the boiler ash confirm the hypothesis that pollutants leach out in higher concentrations from the finer fractions. A large amount of pollutant could be removed from the ashes through sieving, but the goal to produce a fraction that

  6. Sieve estimation in a Markov illness-death process under dual censoring.

    Science.gov (United States)

    Boruvka, Audrey; Cook, Richard J

    2016-04-01

    Semiparametric methods are well established for the analysis of a progressive Markov illness-death process observed up to a noninformative right censoring time. However, often the intermediate and terminal events are censored in different ways, leading to a dual censoring scheme. In such settings, unbiased estimation of the cumulative transition intensity functions cannot be achieved without some degree of smoothing. To overcome this problem, we develop a sieve maximum likelihood approach for inference on the hazard ratio. A simulation study shows that the sieve estimator offers improved finite-sample performance over common imputation-based alternatives and is robust to some forms of dependent censoring. The proposed method is illustrated using data from cancer trials. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. [Removal Characteristics of Elemental Mercury by Mn-Ce/molecular Sieve].

    Science.gov (United States)

    Tan, Zeng-qiang; Niu, Guo-ping; Chen, Xiao-wen; An, Zhen

    2015-06-01

    The impregnation method was used to support molecular sieve with active manganese and cerium components to obtain a composite molecular sieve catalyst. The mercury removal performance of the catalyst was studied with a bench-scale setup. XPS analysis was used to characterize the sample before and after the modification in order to study the changes in the active components of the catalyst prepared. The results showed that the catalyst carrying manganese and cerium components had higher oxidation ability of elemental mercury in the temperature range of 300 degrees C - 450 degrees C, especially at 450 degrees C, the oxidation efficiency of elemental mercury was kept above 80%. The catalyst had more functional groups that were conducive to the oxidation of elemental mercury, and the mercury removal mainly depended on the chemical adsorption. The SO2 and NO in flue gas could inhibit the oxidation of elemental mercury to certain extent.

  8. Polymeric molecular sieve membranes via in situ cross-linking of non-porous polymer membrane templates.

    Science.gov (United States)

    Qiao, Zhen-An; Chai, Song-Hai; Nelson, Kimberly; Bi, Zhonghe; Chen, Jihua; Mahurin, Shannon M; Zhu, Xiang; Dai, Sheng

    2014-04-16

    High-performance polymeric membranes for gas separation are attractive for molecular-level separations in industrial-scale chemical, energy and environmental processes. Molecular sieving materials are widely regarded as the next-generation membranes to simultaneously achieve high permeability and selectivity. However, most polymeric molecular sieve membranes are based on a few solution-processable polymers such as polymers of intrinsic microporosity. Here we report an in situ cross-linking strategy for the preparation of polymeric molecular sieve membranes with hierarchical and tailorable porosity. These membranes demonstrate exceptional performance as molecular sieves with high gas permeabilities and selectivities for smaller gas molecules, such as carbon dioxide and oxygen, over larger molecules such as nitrogen. Hence, these membranes have potential for large-scale gas separations of commercial and environmental relevance. Moreover, this strategy could provide a possible alternative to 'classical' methods for the preparation of porous membranes and, in some cases, the only viable synthetic route towards certain membranes.

  9. High-performance carbon molecular sieve membranes for ethylene/ethane separation derived from an intrinsically microporous polyimide

    KAUST Repository

    Salinas, Octavio; Ma, Xiaohua; Litwiller, Eric; Pinnau, Ingo

    2015-01-01

    An intrinsically microporous polymer with hydroxyl functionalities, PIM-6FDA-OH, was used as a precursor for various types of carbon molecular sieve (CMS) membranes for ethylene/ethane separation. The pristine polyimide films were heated under

  10. Documentation of tests on particle size methodologies for laser diffraction compared to traditional sieving and sedimentation analysis

    DEFF Research Database (Denmark)

    Rasmussen, Charlotte; Dalsgaard, Kristian

    Sieving and sedimentation analyses by pipette or hydrometer are historically the traditional methods for determining particle size distributions (PSD). A more informative and faster alternative has for years been laser diffraction (LD). From 2003 to 2013 the authors of this paper have worked...... intensively with PSD and performed various tests and investigations, using LD, sedimentation (by pipette) and sieving. The aim was to improve and understand the relationship between these various techniques, pre-treatment effects and preferably find a unifying correlation factor. As a result, method...... comparisons of LD and sieving/sedimentation are difficult, as LD is a 3D optical volume measurement, sieving is a 2D width measurement, and sedimentation is density dependent. Platy particles like clay are generally measured to be coarser than traditional methods when LD is used. For LD the clay...

  11. Grubbs Catalysts Immobilized on Mesoporous Molecular Sieves via Phosphine and Pyridine Linkers

    Czech Academy of Sciences Publication Activity Database

    Bek, David; Balcar, Hynek; Žilková, Naděžda; Zukal, Arnošt; Horáček, Michal; Čejka, Jiří

    2011-01-01

    Roč. 1, č. 7 (2011), s. 709-718 ISSN 2155-5435 R&D Projects: GA AV ČR IAA400400805; GA AV ČR KAN100400701; GA ČR GD203/08/H032 Institutional research plan: CEZ:AV0Z40400503 Keywords : Grubbs catalyst * mesoporous molecular sieves * olefin metathesis Subject RIV: CF - Physical ; Theoretical Chemistry

  12. (Al)MCM-41 Molecular Sieves. Aluminium Distribution, Uniformity and Structure of Inner Surface

    Czech Academy of Sciences Publication Activity Database

    Dědeček, Jiří; Žilková, Naděžda; Kotrla, Josef; Čejka, Jiří

    2003-01-01

    Roč. 68, č. 10 (2003), s. 1998-2018 ISSN 0010-0765 R&D Projects: GA ČR GA104/02/0571; GA AV ČR IAA4040001; GA AV ČR IBS4040017 Grant - others:Volkswagen Stiftung(DE) I/75886 Institutional research plan: CEZ:AV0Z4040901 Keywords : molecular sieves * mesoporous materials * Vis spectroscopy Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.041, year: 2003

  13. Simulation of emulsion copolymerization reactions in a continuous pulsed sieve-plate column reactor

    OpenAIRE

    C. Sayer; R. Giudici

    2004-01-01

    This work addressed the viability of using a pulsed sieve-plate column reactor to carry out continuous vinyl acetate/butyl acrylate emulsion copolymerization reactions. A rigorous mathematical model of emulsion copolymerization reactions in a tubular reactor with axial dispersion was used for this purpose. Operational conditions were defined to attain high monomer conversions at the reactor outlet in a relatively short residence time and, at the same time, produce a copolymer with a more homo...

  14. Molecular sieves as dehydrating agent of nonaqueous solutions of rare earths

    International Nuclear Information System (INIS)

    Kuya, M.K.; Mello Filho, A.E.C. de; Oliveira, D. de

    1982-01-01

    Systematic studies on drying solutions of hydrated lanthanide perchlorate salts in acetonitrile and ethanol, with 3A molecular sieves, are performed. Most of water is removed in the first hours period (about 70% in 2hs). Ion exchange process is negligible in ethanol but appreciable in acetonitrile solutions. This drying process may be important during the synthesis of lanthanide coordination compounds, since the success of preparation depends often, on the elimination or reduction of water present in the starting lanthanide solutions. (Author) [pt

  15. Simulation of emulsion copolymerization reactions in a continuous pulsed sieve-plate column reactor

    Directory of Open Access Journals (Sweden)

    Sayer C.

    2004-01-01

    Full Text Available This work addressed the viability of using a pulsed sieve-plate column reactor to carry out continuous vinyl acetate/butyl acrylate emulsion copolymerization reactions. A rigorous mathematical model of emulsion copolymerization reactions in a tubular reactor with axial dispersion was used for this purpose. Operational conditions were defined to attain high monomer conversions at the reactor outlet in a relatively short residence time and, at the same time, produce a copolymer with a more homogeneous composition.

  16. Coreference analysis in clinical notes: a multi-pass sieve with alternate anaphora resolution modules.

    Science.gov (United States)

    Jonnalagadda, Siddhartha Reddy; Li, Dingcheng; Sohn, Sunghwan; Wu, Stephen Tze-Inn; Wagholikar, Kavishwar; Torii, Manabu; Liu, Hongfang

    2012-01-01

    This paper describes the coreference resolution system submitted by Mayo Clinic for the 2011 i2b2/VA/Cincinnati shared task Track 1C. The goal of the task was to construct a system that links the markables corresponding to the same entity. The task organizers provided progress notes and discharge summaries that were annotated with the markables of treatment, problem, test, person, and pronoun. We used a multi-pass sieve algorithm that applies deterministic rules in the order of preciseness and simultaneously gathers information about the entities in the documents. Our system, MedCoref, also uses a state-of-the-art machine learning framework as an alternative to the final, rule-based pronoun resolution sieve. The best system that uses a multi-pass sieve has an overall score of 0.836 (average of B(3), MUC, Blanc, and CEAF F score) for the training set and 0.843 for the test set. A supervised machine learning system that typically uses a single function to find coreferents cannot accommodate irregularities encountered in data especially given the insufficient number of examples. On the other hand, a completely deterministic system could lead to a decrease in recall (sensitivity) when the rules are not exhaustive. The sieve-based framework allows one to combine reliable machine learning components with rules designed by experts. Using relatively simple rules, part-of-speech information, and semantic type properties, an effective coreference resolution system could be designed. The source code of the system described is available at https://sourceforge.net/projects/ohnlp/files/MedCoref.

  17. On the K-th extension of the Sieve of eratosthenes

    OpenAIRE

    Quesada, Antonio R.

    1995-01-01

    The Sieve of Eratosthenes has been recently extended by excluding the multiples of 2, 3, and 5 from the initial set, and finding the additive rules that give the positions of the multiples of the remaining primes. We generalize these results. For a given k we let the initial set Sk consists of natural numbers relatively prime to the first k primes, and find the rules governing the positions of the multiples of the remaining elements.

  18. Comparison of oxidation properties of Nb and Sn in mesoporous molecular sieves

    Czech Academy of Sciences Publication Activity Database

    Nowak, I.; Feliczak, A.; Nekoksová, Iveta; Čejka, Jiří

    2007-01-01

    Roč. 321, č. 1 (2007), s. 40-48 ISSN 0926-860X R&D Projects: GA MPO FT-TA/040; GA AV ČR 1ET400400413 Grant - others:Ministry of Scientific Research and Information Technology(PL) N204 084 31/1965 Institutional research plan: CEZ:AV0Z40400503 Keywords : mesoporous molecular sieves * niobium * tin * synthesis * oxidation properties Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.166, year: 2007

  19. Studies on the hydrodynamic properties of the sieve plate pulsed column for 30% TRPO-kerosene/nitric acid system

    International Nuclear Information System (INIS)

    Ma Ronglin; Chen Jing; Xu Shiping; Wu Qiulin; Tai Derong; Song Chongli

    2000-01-01

    The hydrodynamic properties of the sieve plate pulsed column for 30% TRPO-kerosene/nitric acid system is studied. With the organic phase or aqueous phase as the continuous one, the dispersed phase behaves mainly as coalescing or dispersing, respectively. The sieve plate pulsed column has a fairish flooding throughput for this system. Under the same pulsation intensity, the flooding throughput for the organic phase as the continuous one is more than that for the aqueous phase as the continuous one

  20. Thermal behaviour of molecular sieves (SAPO-11/AIPO-11 type) investigated by synchrotron radiation X-ray diffraction (SRXD)

    International Nuclear Information System (INIS)

    Neissendorfer, F.; Jahn, E.; Gusenko, S.N.; Sheromov, M.A.

    1991-01-01

    The structure of molecular sieves is important for a successful application as a catalyzer. The final structure of the synthetic product depends on the technological steps. This process was investigated by in-situ Synchrotron radiation X-ray diffraction. Structural changes in the molecular sieves exist not only during the heating process but also during the following cooling process. (author) 3 figs., 2 refs

  1. Molecular dynamics simulation of carbon molecular sieve preparation for air separation

    International Nuclear Information System (INIS)

    Yaghoobpour, Elham; Ahmadpour, Ali; Farhadian, Nafiseh; Shariaty-Niassar, Mojtaba

    2015-01-01

    Carbon deposition process on activated carbon (AC) in order to produce carbon molecular sieve (CMS) was simulated using molecular dynamics simulation. The proposed activated carbon for simulation includes micropores with different characteristic diameters and lengths. Three different temperatures of 773 K, 973 K, and 1,273 K were selected to investigate the optimum deposition temperature. Simulation results show that the carbon deposition process at 973 K creates the best adsorbent structure. While at lower temperature some micropore openings are blocked with carbon atoms, at higher temperature the number of deposited carbons on the micropores does not change significantly. Also, carbon deposition process confirms the pseudo-second-order kinetic model with an endothermic behavior. To evaluate the sieving property of adsorbent products, nitrogen and oxygen adsorption on the initial and final adsorbent products are examined. Results show that there is not any considerable difference between the equilibrium adsorption amounts of nitrogen and oxygen on the initial and final adsorbents especially at low pressure (P<10 atm). Although, adsorption kinetics curves of these gases change significantly after the carbon deposition process in comparison with the initial sample. These observations indicate that the final adsorbent has high selectivity towards oxygen compared with the nitrogen, so it can be called a carbon molecular sieve. All simulated results are in good agreement with experiments

  2. Molecular dynamics simulation of carbon molecular sieve preparation for air separation

    Energy Technology Data Exchange (ETDEWEB)

    Yaghoobpour, Elham; Ahmadpour, Ali; Farhadian, Nafiseh [Ferdowsi University of Mashhad, Mashhad (Iran, Islamic Republic of); Shariaty-Niassar, Mojtaba [University of Tehran, Tehran(Iran, Islamic Republic of)

    2015-03-15

    Carbon deposition process on activated carbon (AC) in order to produce carbon molecular sieve (CMS) was simulated using molecular dynamics simulation. The proposed activated carbon for simulation includes micropores with different characteristic diameters and lengths. Three different temperatures of 773 K, 973 K, and 1,273 K were selected to investigate the optimum deposition temperature. Simulation results show that the carbon deposition process at 973 K creates the best adsorbent structure. While at lower temperature some micropore openings are blocked with carbon atoms, at higher temperature the number of deposited carbons on the micropores does not change significantly. Also, carbon deposition process confirms the pseudo-second-order kinetic model with an endothermic behavior. To evaluate the sieving property of adsorbent products, nitrogen and oxygen adsorption on the initial and final adsorbent products are examined. Results show that there is not any considerable difference between the equilibrium adsorption amounts of nitrogen and oxygen on the initial and final adsorbents especially at low pressure (P<10 atm). Although, adsorption kinetics curves of these gases change significantly after the carbon deposition process in comparison with the initial sample. These observations indicate that the final adsorbent has high selectivity towards oxygen compared with the nitrogen, so it can be called a carbon molecular sieve. All simulated results are in good agreement with experiments.

  3. Mixed matrix formulations with MOF molecular sieving for key energy-intensive separations

    KAUST Repository

    Liu, Gongping

    2018-02-09

    Membrane-based separations can improve energy efficiency and reduce the environmental impacts associated with traditional approaches. Nevertheless, many challenges must be overcome to design membranes that can replace conventional gas separation processes. Here, we report on the incorporation of engineered submicrometre-sized metal–organic framework (MOF) crystals into polymers to form hybrid materials that successfully translate the excellent molecular sieving properties of face-centred cubic (fcu)-MOFs into the resultant membranes. We demonstrate, simultaneously, exceptionally enhanced separation performance in hybrid membranes for two challenging and economically important applications: the removal of CO2 and H2S from natural gas and the separation of butane isomers. Notably, the membrane molecular sieving properties demonstrate that the deliberately regulated and contracted MOF pore-aperture size can discriminate between molecular pairs. The improved performance results from precise control of the linkers delimiting the triangular window, which is the sole entrance to the fcu-MOF pore. This rational-design hybrid approach provides a general toolbox for enhancing the transport properties of advanced membranes bearing molecular sieve fillers with sub-nanometre-sized pore-apertures.

  4. Mixed matrix formulations with MOF molecular sieving for key energy-intensive separations

    KAUST Repository

    Liu, Gongping; Chernikova, Valeriya; Liu, Yang; Zhang, Kuang; Belmabkhout, Youssef; Shekhah, Osama; Zhang, Chen; Yi, Shouliang; Eddaoudi, Mohamed; Koros, William J.

    2018-01-01

    Membrane-based separations can improve energy efficiency and reduce the environmental impacts associated with traditional approaches. Nevertheless, many challenges must be overcome to design membranes that can replace conventional gas separation processes. Here, we report on the incorporation of engineered submicrometre-sized metal–organic framework (MOF) crystals into polymers to form hybrid materials that successfully translate the excellent molecular sieving properties of face-centred cubic (fcu)-MOFs into the resultant membranes. We demonstrate, simultaneously, exceptionally enhanced separation performance in hybrid membranes for two challenging and economically important applications: the removal of CO2 and H2S from natural gas and the separation of butane isomers. Notably, the membrane molecular sieving properties demonstrate that the deliberately regulated and contracted MOF pore-aperture size can discriminate between molecular pairs. The improved performance results from precise control of the linkers delimiting the triangular window, which is the sole entrance to the fcu-MOF pore. This rational-design hybrid approach provides a general toolbox for enhancing the transport properties of advanced membranes bearing molecular sieve fillers with sub-nanometre-sized pore-apertures.

  5. Mixed matrix formulations with MOF molecular sieving for key energy-intensive separations

    Science.gov (United States)

    Liu, Gongping; Chernikova, Valeriya; Liu, Yang; Zhang, Kuang; Belmabkhout, Youssef; Shekhah, Osama; Zhang, Chen; Yi, Shouliang; Eddaoudi, Mohamed; Koros, William J.

    2018-03-01

    Membrane-based separations can improve energy efficiency and reduce the environmental impacts associated with traditional approaches. Nevertheless, many challenges must be overcome to design membranes that can replace conventional gas separation processes. Here, we report on the incorporation of engineered submicrometre-sized metal-organic framework (MOF) crystals into polymers to form hybrid materials that successfully translate the excellent molecular sieving properties of face-centred cubic (fcu)-MOFs into the resultant membranes. We demonstrate, simultaneously, exceptionally enhanced separation performance in hybrid membranes for two challenging and economically important applications: the removal of CO2 and H2S from natural gas and the separation of butane isomers. Notably, the membrane molecular sieving properties demonstrate that the deliberately regulated and contracted MOF pore-aperture size can discriminate between molecular pairs. The improved performance results from precise control of the linkers delimiting the triangular window, which is the sole entrance to the fcu-MOF pore. This rational-design hybrid approach provides a general toolbox for enhancing the transport properties of advanced membranes bearing molecular sieve fillers with sub-nanometre-sized pore-apertures.

  6. The Relationship between fenestrations, sieve plates and rafts in liver sinusoidal endothelial cells.

    Directory of Open Access Journals (Sweden)

    Dmitri Svistounov

    Full Text Available Fenestrations are transcellular pores in endothelial cells that facilitate transfer of substrates between blood and the extravascular compartment. In order to understand the regulation and formation of fenestrations, the relationship between membrane rafts and fenestrations was investigated in liver sinusoidal endothelial cells where fenestrations are grouped into sieve plates. Three dimensional structured illumination microscopy, scanning electron microscopy, internal reflectance fluorescence microscopy and two-photon fluorescence microscopy were used to study liver sinusoidal endothelial cells isolated from mice. There was an inverse distribution between sieve plates and membrane rafts visualized by structured illumination microscopy and the fluorescent raft stain, Bodipy FL C5 ganglioside GM1. 7-ketocholesterol and/or cytochalasin D increased both fenestrations and lipid-disordered membrane, while Triton X-100 decreased both fenestrations and lipid-disordered membrane. The effects of cytochalasin D on fenestrations were abrogated by co-administration of Triton X-100, suggesting that actin disruption increases fenestrations by its effects on membrane rafts. Vascular endothelial growth factor (VEGF depleted lipid-ordered membrane and increased fenestrations. The results are consistent with a sieve-raft interaction, where fenestrations form in non-raft lipid-disordered regions of endothelial cells once the membrane-stabilizing effects of actin cytoskeleton and membrane rafts are diminished.

  7. Effects of water vapor on the radiolysis of methane over molecular sieve 5A

    International Nuclear Information System (INIS)

    Shimizu, Y.; Nagai, S.

    1989-01-01

    Effects of the addition of H 2 O on the radiation-induced chemical reaction of methane over molecular sieve 5A at 460 0 C have been studied by product analysis. Hydrogen, carbon monoxide, carbon dioxide and hydrocarbons consisting mainly of C 2 and C 3 alkanes and alkenes were produced from CH 4 + H 2 O mixtures at high conversion levels. The yields of hydrocarbons from 3:1 and 3:2 CH 4 + H 2 O mixtures decreased slightly with time but those from 3:4 mixture showed no decrease with time. When the molecular sieve 5A that had been irradiated in flowing methane was reirradiated in the presence of H 2 O, carbonaceous solid produced from methane on molecular sieve 5A was readily decomposed to carbon dioxide, carbon monoxide, hydrogen and hydrocarbons, mainly alkanes. Therefore, it is concluded that the suppression of decrease of product yields with time by the addition of H 2 O is mainly ascribed to decomposition of the carbonaceous solid by H 2 O under electron beam irradiation. The role of added H 2 O is also discussed in connection with the conventional methane-steam reforming reaction. (author)

  8. Separation of radioactive krypton from carbon dioxide and oxygen with molecular sieves

    International Nuclear Information System (INIS)

    Forsberg, C.W.

    1977-10-01

    In the reprocessing of HTGR nuclear fuels, the off-gas cleanup system generates a stream containing about 1 percent krypton, 90+ percent CO 2 , and various amounts of O 2 , N 2 , and xenon. The krypton is radioactive and must be separated from the CO 2 before it is bottled or zeolite-encapsulated for final disposal. A series of theoretical and experimental investigations to find the best method for separating CO 2 and krypton under the required conditions showed that 5A molecular sieves near O 0 C and 1.01 x 10 5 Pa (1 atm) provided the most effective separation. Molecular sieves are powerful solid adsorbents for CO 2 but weak adsorbents for krypton. For a typical expected CO 2 -O 2 -krytpon gas mixture, a molecular sieve bed adsorbs the CO 2 , allows the O 2 to pass freely through the bed, and concentrates the krypton before it exits the bed. The process selected and investigated is called frontal analysis gas chromatography

  9. A Tale of Three Cell Types: Alkaloid Biosynthesis Is Localized to Sieve Elements in Opium Poppy

    Science.gov (United States)

    Bird, David A.; Franceschi, Vincent R.; Facchini, Peter J.

    2003-01-01

    Opium poppy produces a diverse array of pharmaceutical alkaloids, including the narcotic analgesics morphine and codeine. The benzylisoquinoline alkaloids of opium poppy accumulate in the cytoplasm, or latex, of specialized laticifers that accompany vascular tissues throughout the plant. However, immunofluorescence labeling using affinity-purified antibodies showed that three key enzymes, (S)-N-methylcoclaurine 3′-hydroxylase (CYP80B1), berberine bridge enzyme (BBE), and codeinone reductase (COR), involved in the biosynthesis of morphine and the related antimicrobial alkaloid sanguinarine, are restricted to the parietal region of sieve elements adjacent or proximal to laticifers. The localization of laticifers was demonstrated using antibodies specific to the major latex protein (MLP), which is characteristic of the cell type. In situ hybridization showed that CYP80B1, BBE, and COR gene transcripts were found in the companion cell paired with each sieve element, whereas MLP transcripts were restricted to laticifers. The biosynthesis and accumulation of alkaloids in opium poppy involves cell types not implicated previously in plant secondary metabolism and dramatically extends the function of sieve elements beyond the transport of solutes and information macromolecules in plants. PMID:14508000

  10. A Pervaporation Study of Ammonia Solutions Using Molecular Sieve Silica Membranes

    Directory of Open Access Journals (Sweden)

    Xing Yang

    2014-02-01

    Full Text Available An innovative concept is proposed to recover ammonia from industrial wastewater using a molecular sieve silica membrane in pervaporation (PV, benchmarked against vacuum membrane distillation (VMD. Cobalt and iron doped molecular sieve silica-based ceramic membranes were evaluated based on the ammonia concentration factor downstream and long-term performance. A modified low-temperature membrane evaluation system was utilized, featuring the ability to capture and measure ammonia in the permeate. It was found that the silica membrane with confirmed molecular sieving features had higher water selectivity over ammonia. This was due to a size selectivity mechanism that favoured water, but blocked ammonia. However, a cobalt doped silica membrane previously treated with high temperature water solutions demonstrated extraordinary preference towards ammonia by achieving up to a 50,000 mg/L ammonia concentration (a reusable concentration level measured in the permeate when fed with 800 mg/L of ammonia solution. This exceeded the concentration factor expected by the benchmark VMD process by four-fold, suspected to be due to the competitive adsorption of ammonia over water into the silica structure with pores now large enough to accommodate ammonia. However, this membrane showed a gradual decline in selectivity, suspected to be due to the degradation of the silica material/pore structure after several hours of operation.

  11. MOLECULAR SIEVES AS CATALYSTS FOR METHANOL DEHYDRATION IN THE LPDMEtm PROCESS; TOPICAL

    International Nuclear Information System (INIS)

    Andrew W. Wang

    2002-01-01

    Several classes of molecular sieves were investigated as methanol dehydration catalysts for the LPDME(trademark) (liquid-phase dimethyl ether) process. Molecular sieves offer a number of attractive features as potential catalysts for the conversion of methanol to DME. These include (1) a wide range of acid strengths, (2) diverse architectures and channel connectivities that provide latitude for steric control, (3) high active site density, (4) well-investigated syntheses and characterization, and (5) commercial availability in some cases. We directed our work in two areas: (1) a general exploration of the catalytic behavior of various classes of molecular sieves in the LPDME(trademark) system and (2) a focused effort to prepare and test zeolites with predominantly Lewis acidity. In our general exploration, we looked at such diverse materials as chabazites, mordenites, pentasils, SAPOs, and ALPOs. Our work with Lewis acidity sought to exploit the structural advantages of zeolites without the interfering effects of deleterious Broensted sites. We used zeolite Ultrastable Y (USY) as our base material because it possesses a high proportion of Lewis acid sites. This work was extended by modifying the USY through ion exchange to try to neutralize residual Broensted acidity

  12. The Overshoot Phenomenon in Geodynamics Codes

    Science.gov (United States)

    Kommu, R. K.; Heien, E. M.; Kellogg, L. H.; Bangerth, W.; Heister, T.; Studley, E. H.

    2013-12-01

    The overshoot phenomenon is a common occurrence in numerical software when a continuous function on a finite dimensional discretized space is used to approximate a discontinuous jump, in temperature and material concentration, for example. The resulting solution overshoots, and undershoots, the discontinuous jump. Numerical simulations play an extremely important role in mantle convection research. This is both due to the strong temperature and stress dependence of viscosity and also due to the inaccessibility of deep earth. Under these circumstances, it is essential that mantle convection simulations be extremely accurate and reliable. CitcomS and ASPECT are two finite element based mantle convection simulations developed and maintained by the Computational Infrastructure for Geodynamics. CitcomS is a finite element based mantle convection code that is designed to run on multiple high-performance computing platforms. ASPECT, an adaptive mesh refinement (AMR) code built on the Deal.II library, is also a finite element based mantle convection code that scales well on various HPC platforms. CitcomS and ASPECT both exhibit the overshoot phenomenon. One attempt at controlling the overshoot uses the Entropy Viscosity method, which introduces an artificial diffusion term in the energy equation of mantle convection. This artificial diffusion term is small where the temperature field is smooth. We present results from CitcomS and ASPECT that quantify the effect of the Entropy Viscosity method in reducing the overshoot phenomenon. In the discontinuous Galerkin (DG) finite element method, the test functions used in the method are continuous within each element but are discontinuous across inter-element boundaries. The solution space in the DG method is discontinuous. FEniCS is a collection of free software tools that automate the solution of differential equations using finite element methods. In this work we also present results from a finite element mantle convection

  13. Nothingness and the placebo effect phenomenon

    DEFF Research Database (Denmark)

    Jensen, Tine

    The placebo effect is a pharmacological conundrum, since it is a medical effect that is produced by “nothing” because no pharmacologically active substance is present in placebo. Placebo has, among other things, been defined as an inert substance, often a calcium pill. Simultaneously it presents...... a posthuman angle, applying Karen Barad’s concept of agential realism to tackle the issue of nothingness. I argue that the placebo effect produces specific agencies in the placebo effect phenomenon – that is, both the subject under treatment and the placebo emerge in the placebo effect in the act of measuring it...

  14. Earnings Management: Obvious Phenomenon in Albanian Market

    Directory of Open Access Journals (Sweden)

    Teuta Llukani

    2013-07-01

    This paper is focused on reviewing the existing literature with regard to the Earnings Management in response to the growing pressure of investors, policy makers, and companies’ governance reform mechanisms to curb opportunistic behavior of the managers of these companies. It also examines the existence of this phenomenon in Albanian context as well as tests the importance of Modified Jones Model as an efficient tool for detection of abnormal accruals, used as a proxy for earnings management. The results show that firms in the Albanian market are engaged in earnings management initiatives.

  15. Memoirs as Cultural Phenomenon and Historical Source

    Directory of Open Access Journals (Sweden)

    Наталия Георгиевна Георгиева

    2012-03-01

    Full Text Available The article analyzes the role of memoirs as the native culture phenomenon, process and means of introducing memoirs to the social and scientific and educational practice. The author considers the Russian historians' views development on theoretical and methodological problems of memoirs studies. There are shown the offered variants and achieved results of development of defining «memoirs», studies of their specific peculiarities, principles and schemes of memoirs systematization as well as the criteria of defining their scientific and educational value as historical sources.

  16. Magnetic poles and a still unexplained phenomenon

    International Nuclear Information System (INIS)

    Trower, W.P.

    1981-01-01

    A review is given of ideas about magnetic monopoles. Attention is drawn to the still unexplained observations of Schein, Haskin and Glasser (1954), in which electron-positron pairs were produced in large numbers by a cosmic-ray interaction. Their experiment has been simulated in 300 GeV pN interactions at Fermilab, giving a production limit of 10 -7 per proton interaction. The explanation for this phenomenon may lie in magnetic monopoles, or it may be similar to that invoked to explain the so-called Centauro events. (A.W.)

  17. Cyclic degradation of antagonistic shape memory actuated structures

    International Nuclear Information System (INIS)

    Sofla, A Y N; Elzey, D M; Wadley, H N G

    2008-01-01

    Antagonistic shape memory actuated structures exploit opposing pairs of one-way shape memory alloy (SMA) linear actuators to create devices capable of a fully reversible response. Unlike many conventional reversible SMA devices they do not require bias force components (springs) to return them to their pre-actuated configuration. However, the repeated use of SMA antagonistic devices results in the accumulation of plastic strain in the actuators which can diminish their actuation stroke. We have investigated this phenomenon and the effect of shape memory alloy pre-strain upon it for near equi-atomic NiTi actuators. We find that the degradation eventually stabilizes during cycling. A thermomechanical treatment has been found to significantly reduce degradation in cyclic response of the actuators

  18. Cyclic completion of the anamorphic universe

    Science.gov (United States)

    Ijjas, Anna

    2018-04-01

    Cyclic models of the universe have the advantage of avoiding initial conditions problems related to postulating any sort of beginning in time. To date, the best known viable examples of cyclic models have been ekpyrotic. In this paper, we show that the recently proposed anamorphic scenario can also be made cyclic. The key to the cyclic completion is a classically stable, non-singular bounce. Remarkably, even though the bounce construction was originally developed to connect a period of contraction with a period of expansion both described by Einstein gravity, we show here that it can naturally be modified to connect an ordinary contracting phase described by Einstein gravity with a phase of anamorphic smoothing. The paper will present the basic principles and steps in constructing cyclic anamorphic models.

  19. Detection of Cyclic Dinucleotides by STING.

    Science.gov (United States)

    Du, Xiao-Xia; Su, Xiao-Dong

    2017-01-01

    STING (stimulator of interferon genes) is an essential signaling adaptor protein mediating cytosolic DNA-induced innate immunity for both microbial invasion and self-DNA leakage. STING is also a direct receptor for cytosolic cyclic dinucleotides (CDNs), including the microbial secondary messengers c-di-GMP (3',3'-cyclic di-GMP), 3',3'cGAMP (3',3'-cyclic GMP-AMP), and mammalian endogenous 2',3'cGAMP (2',3'-cyclic GMP-AMP) synthesized by cGAS (cyclic GMP-AMP synthase). Upon CDN binding, STING undergoes a conformational change to enable signal transduction by phosphorylation and finally to active IRF3 (Interferon regulatory factor 3) for type I interferon production. Here, we describe some experimental procedures such as Isothermal Titration Calorimetry and luciferase reporter assays to study the CDNs binding and activity by STING proteins.

  20. Radiation-induced chemical reaction of methane in the presence of X-and Y-type molecular sieves

    International Nuclear Information System (INIS)

    Shimizu, Y.; Nagai, S.

    1990-01-01

    The radiolysis of methane was investigated in the presence of X (13X) and Y (SK-40) type molecular sieves at 300 0 C. Product analysis showed that irradiation of methane over 13X and SK-40 produces hydrogen and hydrocarbons up to C 5 . The yields of hydrocarbons, except for ethylene, over 13X and SK-40 slightly increased with irradiation time. The yields of the main hydrocarbon products over SK-40 were larger than those in the absence of molecular sieve in contrast to those over 13X. It was found that no 13X shows catalytic activity for the radiolysis of methane; on the other hand, SK-40 shows it. The relations between the proportion of hydrocarbon yield of each carbon number to the hydrocarbon total yield over 13X and SK-40 and the carbon number were the same as those in the absence of molecular sieve. It was proved by comparison of these results with those over A-type molecular sieve (5A) that the order of the catalytic activities of the molecular sieves for the radiolysis of methane differs considerably from that found in thermal catalytic reactions. These results are discussed in terms of the concept of energy transfer and the relation between the pore size of the molecular sieves and the molecular diameters of the hydrocarbons produced. (author)

  1. Quality Control of Trichinella Testing at the Slaughterhouse Laboratory: Evaluation of the Use of a 400-Micrometer-Mesh-Size Sieve in the Magnetic Stirrer Method.

    Science.gov (United States)

    Franssen, Frits; van Andel, Esther; Swart, Arno; van der Giessen, Joke

    2016-02-01

    The performance of a 400-μm-mesh-size sieve (sieve400) has not previously been compared with that of a 180-μm-mesh-size sieve (sieve180). Using pork samples spiked with 0 to 10 Trichinella muscle larvae and an artificial digestion method, sieve performance was evaluated for control of Trichinella in meat-producing animals. The use of a sieve400 resulted in 12% lower larval counts, 147% more debris, and 28% longer counting times compared with the use of a sieve180. Although no false-negative results were obtained, prolonged counting times with the sieve400 may have an impact on performance in a high-throughput environment such as a slaughterhouse laboratory. Based on our results, the sieve180 remains the sieve of choice for Trichinella control in meat in slaughterhouse laboratories, according to the European Union reference method (European Commission regulation 2075/2005). Furthermore, the results of the present study contribute to the discussion of harmonization of meat inspection requirements among countries.

  2. [Virchowian Hansen's disease, Lucio's phenomenon, cryptococcosis].

    Science.gov (United States)

    1988-12-01

    A 75 years old white male, for 3 years on treatment for virchowian hanseniasis, was admitted with active HD lesions, infiltration on the base of right lung, leg ulcer and malaise. After two days he developed purpura and hemorrhagic blisters in the limbs. The biopsy of these lesions revealed Lucio phenomenon. The patient worsened with mental confusion, psychomotor agitation and anisocoric pupils. In the 18th day of internation the patient died. Necropsy revealed virchowian infiltration plenty of bacilli in the skin and viscera as well as tuberculoid granuloma with acid-fast bacilli in the liver, spleen and bone marrow. These findings lead us to review the patient's classification from virchowian to borderline. In the lungs, leptomeninge, renal papile, prostate and thyroid it was found loose tuberculoid granuloma with a great amount of fungi surrounded by a gelly halo resembling Criptococcus neoformans. These findings and the onset of Lucio phenomenon are discussed in a patient that has been treated for 3 years and still having several virchowian lesions and a great amount of acid-fast bacilli.

  3. Color doppler imaging of subclavian steal phenomenon

    International Nuclear Information System (INIS)

    Cho, Nari Ya; Chung, Tae Sub; Kim, Jai Keun

    1997-01-01

    To evaluate the characteristic color doppler imaging of vertebral artery flow in the subclavian steal phenomenon. The study group consisted of eight patients with reversed vertebral artery flow proved by color Doppler imaging. We classified this flow into two groups:(1) complete reversal;(2) partial reversal, as shown by Doppler velocity waveform. Vertebral angiography was performed in six of eight patients;color Doppler imaging and angiographic findings were compared. On color Doppler imaging, all eight cases with reversed vertebral artery flow showed no signal at the proximal subclavian or brachiocephalic artery. We confirmed shunting of six cases by performing angiography from the contralateral vertebral and basilar artery to the ipsilateral vertebral artery. On the Doppler spectrum, six cases showed complete reversal and two partial reversal. On angiography, one partial reversal case showed complete occlusion of the subclavian artery with abundant collateral circulation of muscular branches of the vertebral artery. On color Doppler imaging, a reversed vertebral artery suggests the subclavian steal phenomenon. In particular, partial reversal waveform may reflect collateral circulation

  4. The happy victimizer phenomenon: Not found here

    Directory of Open Access Journals (Sweden)

    Jevtić Ana

    2014-01-01

    Full Text Available Children’s attribution of emotions to a moral transgressor is an important research topic in the psychology of moral and emotional development. This is especially because of the so-called Happy Victimizer Phenomenon (HVP where younger children attribute positive emotions to a moral transgressor described in a story. In the two studies that we have conducted (children aged 5, 7 and 9, 20 of each age; 10 of each age in the second study we have tested the possible influence of the fear of sanctions and the type of transgression (stealing and inflicting body injuries on the attribution of emotions. Children were presented with stories that described transgressions and they were asked to answer how the transgressor felt. The fear of sanctions did not make a significant difference in attribution but the type of transgression did - more negative emotions were attributed for inflicting body injuries than for stealing. Positive emotions were explained with situational-instrumental explanations in 84% of cases while negative emotions were explained with moral explanations in 63,5%. Girls attributed more positive emotions (61% than boys (39%. However, our main finding was that, for the aforementioned age groups, we did not find the HVP effect although it has regularly been registered in foreign studies. This finding denies the generalizability of the phenomenon and points to the significance of disciplining styles and, even more so, culture for children’s attribution of emotions to moral transgressors.

  5. Turnpike phenomenon and infinite horizon optimal control

    CERN Document Server

    Zaslavski, Alexander J

    2014-01-01

    This book is devoted to the study of the turnpike phenomenon and describes the existence of solutions for a large variety of infinite horizon optimal control classes of problems.  Chapter 1 provides introductory material on turnpike properties. Chapter 2 studies the turnpike phenomenon for discrete-time optimal control problems. The turnpike properties of autonomous problems with extended-value intergrands are studied in Chapter 3. Chapter 4 focuses on large classes of infinite horizon optimal control problems without convexity (concavity) assumptions. In Chapter 5, the turnpike results for a class of dynamic discrete-time two-player zero-sum game are proven. This thorough exposition will be very useful  for mathematicians working in the fields of optimal control, the calculus of variations, applied functional analysis, and infinite horizon optimization. It may also be used as a primary text in a graduate course in optimal control or as supplementary text for a variety of courses in other disciplines. Resea...

  6. Specificity of the Cyclic GMP-Binding Activity and of a Cyclic GMP-Dependent Cyclic GMP Phosphodiesterase in Dictyostelium discoideum

    NARCIS (Netherlands)

    Haastert, Peter J.M. van; Walsum, Hans van; Meer, Rob C. van der; Bulgakov, Roman; Konijn, Theo M.

    1982-01-01

    The nucleotide specificity of the cyclic GMP-binding activity in a homogenate of Dictyostelium discoideum was determined by competition of cyclic GMP derivatives with [8-3H] cyclic GMP for the binding sites. The results indicate that cyclic GMP is bound to the binding proteins by hydrogen bonds at

  7. Cyclic characteristics of earthquake time histories

    International Nuclear Information System (INIS)

    Hall, J.R. Jr; Shukla, D.K.; Kissenpfennig, J.F.

    1977-01-01

    From an engineering standpoint, an earthquake record may be characterized by a number of parameters, one of which is its 'cyclic characteristics'. The cyclic characteristics are most significant in fatigue analysis of structures and liquefaction analysis of soils where, in addition to the peak motion, cyclic buildup is significant. Whereas duration peak amplitude and response spectra for earthquakes have been studied extensively, the cyclic characteristics of earthquake records have not received an equivalent attention. Present procedures to define the cyclic characteristics are generally based upon counting the number of peaks at various amplitude ranges on a record. This paper presents a computer approach which describes a time history by an amplitude envelope and a phase curve. Using Fast Fourier Transform Techniques, an earthquake time history is represented as a projection along the x-axis of a rotating vector-the length the vector is given by the amplitude spectra-and the angle between the vector and x-axis is given by the phase curve. Thus one cycle is completed when the vector makes a full rotation. Based upon Miner's cumulative damage concept, the computer code automatically combines the cycles of various amplitudes to obtain the equivalent number of cycles of a given amplitude. To illustrate the overall results, the cyclic characteristics of several real and synthetic earthquake time histories have been studied and are presented in the paper, with the conclusion that this procedure provides a physical interpretation of the cyclic characteristics of earthquakes. (Auth.)

  8. The United States pork niche market phenomenon.

    Science.gov (United States)

    Honeyman, M S; Pirog, R S; Huber, G H; Lammers, P J; Hermann, J R

    2006-08-01

    After the broad industrialization of the US pork industry, there has been a development of niche markets for export and domestic pork; that is, there is a pork niche market phenomenon. The US pork niche market phenomenon is characterized, and 2 of the major markets are explained in detail. With the Midwest's tradition of a diversified family-based agriculture and record low hog prices of the late 1990s, the conditions were conducive for this phenomenon to develop. Pork niche markets utilize various sales methods including Internet sales, local abattoir sales, direct marketing, farmer networks, and targeting to organized groups. In 2003, there were approximately 35 to 40 active pork niche marketing efforts in Iowa. The Berkshire breed is an example of a swine breed that has had a recent resurgence because of niche markets. Berkshire pork is known for tenderness and excellent quality. Berkshire registrations have increased 4-fold in the last 10 yr. One of the larger niche marketers of "natural pork" is Niman Ranch Pork, which has more than 400 farmer-producers and processes about 2,500 pigs weekly. Many US consumers of pork are interested in issues concerning the environment, food safety, pig welfare, and pig farm ownership and structure. These consumers may be willing to pay more for pork from farmers who are also concerned about these issues. Small- and medium-sized swine farmers are active in pork niche markets. Niche markets claim product differentiation by superior or unique product quality and social attributes. Quality attributes include certain swine breeds, and meat quality, freshness, taste or flavor, and tenderness. Social or credence attributes often are claimed and include freedom from antibiotics and growth promotants; local family farm production; natural, organic, outdoor, or bedded rearing; humane rearing; known origin; environmentally friendly production; and the absence of animal by-products in the feed. Niche pork markets and alternative swine

  9. Phenomenon of Uncertainty as a Subjective Experience

    Directory of Open Access Journals (Sweden)

    Lifintseva A.A.

    2018-04-01

    Full Text Available The phenomenon of uncertainty in illness of patients is discussed and analyzed in this article. Uncertainty in illness is a condition that accompanies the patient from the moment of appearance of the first somatic symptoms of the disease and could be strengthened or weakened thanks to many psychosocial factors. The level of uncertainty is related to the level of stress, emotional disadaptation, affective states, coping strategies, mechanisms of psychological defense, etc. Uncertainty can perform destructive functions, acting as a trigger for stressful conditions and launching negative emotional experiences. As a positive function of uncertainty, one can note a possible positive interpretation of the patient's disease. In addition, the state of uncertainty allows the patient to activate the resources of coping with the disease, among which the leading role belongs to social support.

  10. FOREIGN FIGHTERS PHENOMENON IN THE EUROPEAN UNION

    Directory of Open Access Journals (Sweden)

    Florin-Alexandru LUCA

    2018-06-01

    Full Text Available Hybrid war is a reality; war does not depend only on conventional means, but includes communication and propaganda strategies whose role is increasingly important. In the last few years, terrorist cells have spent and keep spending many energies in a global propaganda business. This activity is a fundamental aspect of the conflict. This promotion campaign serves several purposes: legitimating its authority, recruiting militants and motivating sympathizers, and intimidating and conditioning those whose cells they consider enemies. What draws our attention is the sophisticated level of professionalism they demonstrate in managing propaganda and terror. This paper seeks to provide a broader view of the European Foreign Fighters (FF phenomenon by analyzing this target group from a marketing point of view in order to lay the foundations for a strategy to counteract them.

  11. Melting phenomenon and laser annealing in semiconductors

    International Nuclear Information System (INIS)

    Narayan, J.

    1981-03-01

    The work on annealing of displacement damage, dissolution of boron precipitates, and the broadening of dopant profiles in semiconductors after treating with ruby and dye laser pulses is reviewed in order to provide convincing evidence for the melting phenomenon and illustrate the mechanism associated with laser annealing. The nature of the solid-liquid interface and the interface instability during rapid solidification is considered in detail. It is shown that solute concentrations after pulsed laser annealing can far exceed retrograde maxima values. However, there is a critical solute concentration above which a planar solid-liquid interface becomes unstable and breaks into a cellular structure. The solute concentrations and cell sizes associated with this instability are calculated using a perturbation theory, and compared with experimental results

  12. [Electroencephalographic characteristics of the deja vu phenomenon].

    Science.gov (United States)

    Vlasov, P N; Cherviakov, A V; Gnezdinsiĭ, V V

    2013-01-01

    Déjà vu (DV, from French "already seen") is an aberration of psychic activity associated with transitory erroneous perception of novel circumstances, objects, or people as already known. An aim of the study was to investigate EEG characteristics of DV in patients with epilepsy. We studied 166 people (63.2% women, mean age 25.17±9.19 years). The DV phenomenon was studied in patients (27 people) and in a control group (139 healthy people). Patients were interviewed for DV characteristics and underwent a long (12-16 h) ambulatory EEG-monitoring study. In EEG, DV episodes in patients began with polyspike activity in the right temporal lobe and, in some cases, ended with the slow-wave theta-delta activity in the right hemisphere.

  13. Physics of cryogenics an ultralow temperature phenomenon

    CERN Document Server

    Zohuri, Bahman

    2018-01-01

    Physics of Cryogenics: An Ultralow Temperature Phenomenon discusses the significant number of advances that have been made during the last few years in a variety of cryocoolers, such as Brayton, Joule-Thomson, Stirling, pulse tube, Gifford-McMahon and magnetic refrigerators. The book reviews various approaches taken to improve reliability, a major driving force for new research areas. The advantages and disadvantages of different cycles are compared, and the latest improvements in each of these cryocoolers is discussed. The book starts with the thermodynamic fundamentals, followed by the definition of cryogenic and the associated science behind low temperature phenomena and properties. This book is an ideal resource for scientists, engineers and graduate and senior undergraduate students who need a better understanding of the science of cryogenics and related thermodynamics.

  14. PUBLIC RELATIONS AS AN INFORMATION PROCESS PHENOMENON

    Directory of Open Access Journals (Sweden)

    TKACH L. M.

    2016-06-01

    Full Text Available Formulation of the problem. If public relations as a phenomenon of information management are examined, we deal with the question of knowledge content and nature of relationship of PR with environment, ability to manage the perception and attitude of people to events in the environment; ensure priority of information over other resources. Goal. To investigate the concept of "public relations" of foreign and domestic experts; consider the typology of the public and the "laws" of public opinion; define the basic principles according to which relations with public should be built, and to identify PR activities as a kind of social communication. Conclusions. Public relations on the basis of advanced information and communication technologies create fundamentally new opportunities for information control and influence on public consciousness.

  15. Assessing Self-Regulation as a Cyclical, Context-Specific Phenomenon: Overview and Analysis of SRL Microanalytic Protocols

    Directory of Open Access Journals (Sweden)

    Timothy J. Cleary

    2012-01-01

    Full Text Available The primary purpose of this paper is to review relevant research related to the use of an assessment technique, called Self-Regulated Learning (SRL Microanalysis. This structured interview is grounded in social-cognitive theory and research and thus seeks to evaluate students' regulatory processes as they engage in well-defined academic or nonacademic tasks and activities. We illustrate the essential features of this contextualized assessment approach and detail a simple five-step process that researchers can use to apply this approach to their work. Example questions and administration procedures for five key self-regulation subprocesses (i.e., including goal-setting, strategic planning, monitoring, self-evaluation, and attributions are highlighted, with particular emphasis placed on causal attributions. The psychometric properties of SRL microanalytic assessment protocols and potential areas of future research are presented.

  16. Prussian phenomenon and its historical distortion

    Directory of Open Access Journals (Sweden)

    Oleg Y. Plenkov

    2016-03-01

    Full Text Available The article deals with the phenomenon of Prussia. Once, Prussia had been the largest continental Protestant state in Europe. The main issue of this phenomenon is that upon the tragic events of the World War II Prussian history and heritage had been considerably distorted, in order to compensate somehow for the dreadful casualties suffered by the victorious powers. The common European misconception implied that Prussia had been the bulwark of militarism, and therefore had to bear all the responsibility for the atrocities of war. Unfortunately, the majority of modern German historians share such misinterpretation of Prussian heritage in order to please false political correctness, perhaps, as an act of contrition for National Socialism and its crimes. However, the Prussian tradition and history go far beyond this militarism, and this article explains what ways. The authors believe that there should not be any prejudices and biases, that any subject should be examined sine ira et studio. Moreover, given that it is possible to characterize the Great French Revolution as a juristic one, and the Great October revolution – as a social one, the Prussian revolution “from above”, led by the first representatives of the Hohenzollern family, may be well considered as a pedagogical revolution. This revolution did bring definitely positive changes; they are surveyed in the article. The French Revolution has not eliminated the covetousness of the bourgeoisie after 1789; despotism of the authorities and people’s passiveness similarly have remained unaltered in Russia after 1917. On the contrary, Federal Republic of Germany of nowadays, distinctive for its law, order and effective responsible government is unthinkable without Prussian heritage.

  17. SUBJECTIVE RESOURCESTHE PSYCHOLOGICAL AND ACMEOLOGICAL PHENOMENON

    Directory of Open Access Journals (Sweden)

    Marina Ivanovna Ilyushina

    2017-02-01

    Full Text Available The article is devoted to the moment the subject – resources of a person. Be caused, “loss” possible resources: lack of personal self-realization, the maladjustment of the individual in a social environment, obstructed line of identity, which in some cases is accompanied by incomplete personal self-actualization and self-sufficiency. The article emphasizes the importance of the subjective component in understanding, identifying, understanding, mobilization, conservation and accumulation of resources of the individual. Man is an active Converter to your reality, where he and reality are the result of the conversion and source conversion. The author proposed the concept of “subjective resource” as a necessary factor for quality of life of the individual, achievement of tops of her self-improvement and self-development, both professionally and personally. Subjective component emphasizes the role of the individual in the conservation, transformation, accumulation, the reallocation of resources. Purpose. The subject of analysis is the awareness, understanding person own resources – the subjective resourcest. The author aims to describe the subjective resourcest as psychological and acmeological phenomenon to reveal its essence and to suggest the methodology of the study of this phenomenon, showing the importance of verbalization resources through associative image without relying on the visibility and relying on her. Methodology. The basis of the study form a General theoretical methods (theoretical analysis, including psychological analysis, generalization, systematization, system description. Results. The results of the work lies in the fact that the author has defined the concept of “subjective resourcesthe” and proposed methodology of the study. The obtained results may be of interest to improve the efficiency of the work to define the resources of the individual. The results and method of determining a subjective resource

  18. Neutron activation analysis of trace metallic elements eluted from molecular sieves in the dehydration process of safflower oil

    Energy Technology Data Exchange (ETDEWEB)

    Takasago, Masahisa; Kobayashi, Koichi; Taru, Yasunori; Takaoka, Kyo (Musashi Inst. of Tech., Tokyo (Japan))

    1992-11-01

    Dissolved water in safflower oil affects the autoxidation of this oil significantly. Molecular sieves were used to remove the dissolved water from the oil. This method is much simpler than that of distillation, and dissolved water can be removed to the same extent as that by distillation. But, due to the elution of many kinds of trace metallic elements in the oil dehydrated with molecular sieves, these elements were analyzed by neutron activation analysis. For a data comparison trace amounts of metallic elements in the oil dehydrated by distillation were also analyzed. Since the intensity of the [gamma] ray-photoelectric peak of nuclide [sup 28]Al was largest among the detected elements, this element was analyzed quantitatively and the other elements qualitatively. In safflower oil dehydrated with molecular sieves, 14 kinds of the elements (I, Br, Al, Mg, Si, V, Cl, Nd, Ta, Cr, Sb, Cs, Co, Na) were detected. Also, I, Br, Cl, Cr, Ta, Sb, and Al elements were detected in the oil dehydrated by distillation. The intensity of the photoelectric peak of nuclide except [sup 28]Al was essentially the same as that in the oil dehydrated by distillation, but the intensity of [sup 28]Al in the oil with molecular sieves was about 28 times stronger than that in distillation oil. In the molecular sieves, 19 impure elements in addition to the original constituents (Na, K, Al, si, O) were detected. It was Al, Na, Si, Nd, Cs, and Co along with impure elements may possibly have been eluted in the oil. Al element in safflower oil dehydrated with molecular sieves was analyzed quantitatively. 0.91 ppm of Al was detected in safflower oil. The eluted amount of Al in safflower oil dehydrated by distillation was 0.032 ppm. A larger amount of Al element was thus eluted into the oil dehydrated with molecular sieves than by distillation. (author).

  19. Neutron activation analysis of trace metallic elements eluted from molecular sieves in the dehydration process of safflower oil

    International Nuclear Information System (INIS)

    Takasago, Masahisa; Kobayashi, Koichi; Taru, Yasunori; Takaoka, Kyo

    1992-01-01

    Dissolved water in safflower oil affects the autoxidation of this oil significantly. Molecular sieves were used to remove the dissolved water from the oil. This method is much simpler than that of distillation, and dissolved water can be removed to the same extent as that by distillation. But, due to the elution of many kinds of trace metallic elements in the oil dehydrated with molecular sieves, these elements were analyzed by neutron activation analysis. For a data comparison trace amounts of metallic elements in the oil dehydrated by distillation were also analyzed. Since the intensity of the γ ray-photoelectric peak of nuclide 28 Al was largest among the detected elements, this element was analyzed quantitatively and the other elements qualitatively. In safflower oil dehydrated with molecular sieves, 14 kinds of the elements (I, Br, Al, Mg, Si, V, Cl, Nd, Ta, Cr, Sb, Cs, Co, Na) were detected. Also, I, Br, Cl, Cr, Ta, Sb, and Al elements were detected in the oil dehydrated by distillation. The intensity of the photoelectric peak of nuclide except 28 Al was essentially the same as that in the oil dehydrated by distillation, but the intensity of 28 Al in the oil with molecular sieves was about 28 times stronger than that in distillation oil. In the molecular sieves, 19 impure elements in addition to the original constituents (Na, K, Al, si, O) were detected. It was Al, Na, Si, Nd, Cs, and Co along with impure elements may possibly have been eluted in the oil. Al element in safflower oil dehydrated with molecular sieves was analyzed quantitatively. 0.91 ppm of Al was detected in safflower oil. The eluted amount of Al in safflower oil dehydrated by distillation was 0.032 ppm. A larger amount of Al element was thus eluted into the oil dehydrated with molecular sieves than by distillation. (author)

  20. Cyclic voltammetry and reduction mechanistic studies of ...

    African Journals Online (AJOL)

    styrylpyrylium perchlorates have been evaluated using cyclic voltammetry, in comparison to their non-methylated derivatives values. The reduction peak of all studied compounds remained chemically irreversible. The presence of the ...

  1. A cyclically actuated electrolytic drug delivery device

    KAUST Repository

    Yi, Ying; Buttner, Ulrich; Foulds, Ian G.

    2015-01-01

    This work, focusing on an implantable drug delivery system, presents the first prototype electrolytic pump that combines a catalytic reformer and a cyclically actuated mode. These features improve the release performance and extend the lifetime

  2. Introduction of a cyclic-fermentation method

    Energy Technology Data Exchange (ETDEWEB)

    Makarova, C P

    1958-01-01

    Equipment is described, consisting of 8 kettles, which permits a cyclic fermentation process and continuous ethanol production; 100% yields of ethanol are obtained, based on the starch content in grain.

  3. Results on Cyclic Signal Processing Systems

    National Research Council Canada - National Science Library

    Vaidyanathan, P

    1998-01-01

    .... A number of related problems such as the paraunitary interpolation problem and the cyclic paraunitary factorizability problem can be understood in a unified way by using the realization matrix...

  4. Cyclical Variability of Prominences, CMEs and Flares

    Indian Academy of Sciences (India)

    tribpo

    For many years, qualitative studies were made about the cyclical ... plan to review the more recent research concerning all these topics. Key words. ... are distributed in three narrow zones, which show different types of time-latitude behaviour.

  5. Anodic selective functionalization of cyclic amine derivatives

    OpenAIRE

    Onomura, Osamu

    2012-01-01

    Anodic reactions are desirable methods from the viewpoint of Green Chemistry, since no toxic oxidants are necessary for the oxidation of organic molecules. This review introduces usefulness of anodic oxidation and successive reaction for selective functionalization of cyclic amine derivatives.

  6. Macromolecular Networks Containing Fluorinated Cyclic Moieties

    Science.gov (United States)

    2015-12-12

    Briefing Charts 3. DATES COVERED (From - To) 17 Nov 2015 – 12 Dec 2015 4. TITLE AND SUBTITLE Macromolecular Networks Containing Fluorinated Cyclic... FLUORINATED CYCLIC MOIETIES 12 December 2015 Andrew J. Guenthner,1 Scott T. Iacono,2 Cynthia A. Corley,2 Christopher M. Sahagun,3 Kevin R. Lamison,4...Reinforcements Good Flame, Smoke, & Toxicity Characteristics Low Water Uptake with Near Zero Coefficient of Hygroscopic Expansion ∆ DISTRIBUTION A

  7. The Cyclicality of New Product Introductions

    OpenAIRE

    Kostas Axarloglou

    2003-01-01

    This study analyzes empirically the cyclical nature of the timing of new product introductions in U.S. manufacturing. New product introductions vary more in nonseasonal frequencies than in seasonal frequencies. However, the seasons alone account for only a small part of their total variability with demand factors being much more important. Demand fluctuations account for 35%80% and 17%43%, respectively, of the seasonal and cyclical variability of new product introductions in various industrie...

  8. 3' : 5'-Cyclic AMP-dependent 3'

    NARCIS (Netherlands)

    Mato, José M.; Krens, Frans A.; Haastert, Peter J.M. van; Konijn, Theo M.

    1977-01-01

    Suspensions of 3':5'-cyclic AMP (cAMP)-sensitive cells of Dictyostelium discoideum responded to a cAMP pulse with increased 3':5'-cyclic GMP (cGMP) levels. Under the assay conditions used (2 × 10^8 cells per ml in 10 mM phosphate buffer, pH 6.0) cAMP (5 × 10-8 M final concentration) increased cGMP

  9. The calculation of dissipated work, elastoplastic cyclic stress and cyclic strain in a structure

    International Nuclear Information System (INIS)

    Wang Xucheng; Xie Yihuan.

    1986-01-01

    With the development of the reactor technique, there is being an increasing interest in the calculation of elastoplastic response of a structure to its complex loading. This paper introduces a constitutive relation of a material for discribing unloading property, and uses it in an analysis of a real structure under a cyclic loading. The results, which include cyclic stress, cyclic strain and dissipated work, are meaningful in the researches of the structure behavior under complex loading and of the structural safety

  10. A tale of two neglected systems - structure and function of the thin- and thick-walled sieve tubes in monocotyledonous leaves.

    Directory of Open Access Journals (Sweden)

    Ted eBotha

    2013-08-01

    Full Text Available There is a large body of information relating to the ontogeny, development and the vasculature of eudicotyledonous leaves. However there is less information available concerning the vascular anatomy of monocotyledonous leaves. This is surprising, given that there are two uniquely different phloem systems present in large groups such as grasses and sedges. Monocotyledonous leaves contain marginal, large, intermediate and small longitudinal veins that are interconnected by numerous transverse veins. The longitudinal veins contain two metaphloem sieve tube types, which, based upon their ontogeny and position within the phloem, are termed early (thin-walled and late (thick-walled sieve tubes. Early metaphloem comprises sieve tubes, companion cells and vascular parenchyma cells, whilst the late metaphloem, contains thick-walled sieve tubes that lack companion cells. Thick-walled sieve tubes are generally adjacent to, or no more than one cell removed from the metaxylem. Unlike thin-walled sieve tube-companion cell complexes, thick-walled sieve tubes are connected to parenchyma by pore-plasmodesma units and are generally symplasmically isolated from the thin walled sieve tubes. This paper addresses key structural and functional differences between thin- and thick-walled sieve tubes and explores the unique advantages of alternate transport strategies that this 5 to 7 million year old dual system may offer. It would seem that these two systems may enhance, add to, or play a significant role in increasing the efficiency of solute retrieval as well as of assimilate transfer.

  11. Phytoplasma infection in tomato is associated with re-organization of plasma membrane, ER stacks, and actin filaments in sieve elements.

    Science.gov (United States)

    Buxa, Stefanie V; Degola, Francesca; Polizzotto, Rachele; De Marco, Federica; Loschi, Alberto; Kogel, Karl-Heinz; di Toppi, Luigi Sanità; van Bel, Aart J E; Musetti, Rita

    2015-01-01

    Phytoplasmas, biotrophic wall-less prokaryotes, only reside in sieve elements of their host plants. The essentials of the intimate interaction between phytoplasmas and their hosts are poorly understood, which calls for research on potential ultrastructural modifications. We investigated modifications of the sieve-element ultrastructure induced in tomato plants by 'Candidatus Phytoplasma solani,' the pathogen associated with the stolbur disease. Phytoplasma infection induces a drastic re-organization of sieve-element substructures including changes in plasma membrane surface and distortion of the sieve-element reticulum. Observations of healthy and stolbur-diseased plants provided evidence for the emergence of structural links between sieve-element plasma membrane and phytoplasmas. One-sided actin aggregates on the phytoplasma surface also inferred a connection between phytoplasma and sieve-element cytoskeleton. Actin filaments displaced from the sieve-element mictoplasm to the surface of the phytoplasmas in infected sieve elements. Western blot analysis revealed a decrease of actin and an increase of ER-resident chaperone luminal binding protein (BiP) in midribs of phytoplasma-infected plants. Collectively, the studies provided novel insights into ultrastructural responses of host sieve elements to phloem-restricted prokaryotes.

  12. Preliminary Evaluation of Cesium Distribution for Wet Sieving Process Planned for Soil Decontamination in Japan - 13104

    Energy Technology Data Exchange (ETDEWEB)

    Enokida, Y.; Tanada, Y.; Hirabayashi, D. [Graduate School of Engineering, 1 Furo-cho Nagoya-shi, Aichi-ken, 4648603 (Japan); Sawada, K. [EcoTopia Science Institute, Nagoya University, 1 Furo-cho Nagoya-shi, Aichi-ken, 4648603 (Japan)

    2013-07-01

    For the purpose of decontaminating radioactive cesium from a huge amount of soil, which has been estimated to be 1.2x10{sup 8} m{sup 3} by excavating to a 5-cm depth from the surface of Fukushima Prefecture where a severe nuclear accident occurred at TEPCO's power generating site and has emitted a significant amount of radioactive materials, mainly radioactive cesium, a wet sieving process was selected as one of effective methods available in Japan. Some private companies have demonstrated this process for soil treatment in the Fukushima area by testing at their plants. The results were very promising, and a full-fledged application is expected to follow. In the present study, we spiked several aqueous samples containing soil collected from an industrial wet sieving plant located near our university for the recycling of construction wastes with non-radioactive cesium hydroxide. The present study provides scientific data concerning the effectiveness in volume reduction of the contaminated soil by a wet sieving process as well as the cesium distribution between the liquid phase and clay minerals for each sub-process of the full-scale one, but a simulating plant equipped with a process of coagulating sedimentation and operational safety fundamentals for the plant. Especially for the latter aspect, the study showed that clay minerals of submicron size strongly bind a high content of cesium, which was only slightly removed by coagulation with natural sedimentation (1 G) nor centrifugal sedimentation (3,700 G) and some of the cesium may be transferred to the effluent or recycled water. By applying ultracentrifugation (257,000 G), most of submicron clay minerals containing cesium was removed, and the cesium amount which might be transferred to the effluent or recycled water, could be reduced to less than 2.3 % of the original design by the addition of a cesium barrier consisting of ultracentrifugation or a hollow fiber membrane. (authors)

  13. An Ideal Molecular Sieve for Acetylene Removal from Ethylene with Record Selectivity and Productivity.

    Science.gov (United States)

    Li, Bin; Cui, Xili; O'Nolan, Daniel; Wen, Hui-Min; Jiang, Mengdie; Krishna, Rajamani; Wu, Hui; Lin, Rui-Biao; Chen, Yu-Sheng; Yuan, Daqiang; Xing, Huabin; Zhou, Wei; Ren, Qilong; Qian, Guodong; Zaworotko, Michael J; Chen, Banglin

    2017-12-01

    Realization of ideal molecular sieves, in which the larger gas molecules are completely blocked without sacrificing high adsorption capacities of the preferred smaller gas molecules, can significantly reduce energy costs for gas separation and purification and thus facilitate a possible technological transformation from the traditional energy-intensive cryogenic distillation to the energy-efficient, adsorbent-based separation and purification in the future. Although extensive research endeavors are pursued to target ideal molecular sieves among diverse porous materials, over the past several decades, ideal molecular sieves for the separation and purification of light hydrocarbons are rarely realized. Herein, an ideal porous material, SIFSIX-14-Cu-i (also termed as UTSA-200), is reported with ultrafine tuning of pore size (3.4 Å) to effectively block ethylene (C 2 H 4 ) molecules but to take up a record-high amount of acetylene (C 2 H 2 , 58 cm 3 cm -3 under 0.01 bar and 298 K). The material therefore sets up new benchmarks for both the adsorption capacity and selectivity, and thus provides a record purification capacity for the removal of trace C 2 H 2 from C 2 H 4 with 1.18 mmol g -1 C 2 H 2 uptake capacity from a 1/99 C 2 H 2 /C 2 H 4 mixture to produce 99.9999% pure C 2 H 4 (much higher than the acceptable purity of 99.996% for polymer-grade C 2 H 4 ), as demonstrated by experimental breakthrough curves. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Superior lithium adsorption and required magnetic separation behavior of iron-doped lithium ion-sieves

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shulei; Zheng, Shili; Wang, Zheming; Cui, Wenwen; Zhang, Hailin; Yang, Liangrong; Zhang, Yi; Li, Ping

    2018-01-01

    The recent research on adsorption-based lithium recovery from lithium-containing solutions has been centred on adsorption capacity and separation of lithium ion-sieves powder from solutions. Herein, an effective iron-doped lithium titanium oxide (Fe-doped Li2TiO3) was synthesized by Fe-doping via solid state reactions followed by acid treatment to form iron-doped lithium ion-sieves (Fe/Ti-x(H)). The resulting solid powder displays both superior adsorption capacity of lithium and high separation efficiency of the adsorbent from the solutions. SEM imaging and BET surface area measurement results showed that at Fe doping levels x0.15, Fe-doping led to grain shrinkage as compared to Li2TiO3 and at the same time the BET surface area increased. The Fe/Ti-0.15(H) exhibited saturated magnetization values of 13.76 emu g-1, allowing effective separation of the material from solid suspensions through the use of a magnet. Consecutive magnetic separation results suggested that the Fe/Ti-0.15(H) powders could be applied at large-scale and continuously removed from LiOH solutions with separation efficiency of 96% or better. Lithium adsorption studies indicated that the equilibrium adsorption capacity of Fe/Ti-0.15(H) in LiOH 2 solutions (1.8 g L-1 Li, pH 12) reached 53.3 mg g-1 within 24 h, which was higher than that of pristine Li2TiO3 (50.5 mg g-1) without Fe doping. Competitive adsorption and regeneration results indicated that the Fe/Ti-0.15(H) possessed a high selectivity for Li with facile regeneration. Therefore, it could be expected that the iron-doped lithium ion-sieves have practical applicability potential for large scale lithium extraction and recovery from lithium-bearing solutions.

  15. Molecular mobility of nematic E7 confined to molecular sieves with a low filling degree.

    Science.gov (United States)

    Brás, A R; Frunza, S; Guerreiro, L; Fonseca, I M; Corma, A; Frunza, L; Dionísio, M; Schönhals, A

    2010-06-14

    The nematic liquid crystalline mixture E7 was confined with similar filling degrees to molecular sieves with constant composition but different pore diameters (from 2.8 to 6.8 nm). Fourier transform infrared analysis proved that the E7 molecules interact via the cyanogroup with the pore walls of the molecular sieves. The molecular dynamics of the system was investigated by broadband dielectric spectroscopy (10(-2)-10(9) Hz) covering a wide temperature range of approximately 200 K from temperatures well above the isotropic-nematic transition down to the glass transition of bulk E7. A variety of relaxation processes is observed including two modes that are located close to the bulk behavior in its temperature dependence. For all confined samples, two relaxation processes, at frequencies lower than the processes observed for the bulk, were detected. At lower temperatures, their relaxation rates have different temperature dependencies whereas at higher temperatures, they seem to collapse into one chart. The temperature dependence of the slowest process (S-process) obeys the Vogel-Fulcher-Tammann law indicating a glassy dynamics of the E7 molecules anchored to the pore surface. The pore size dependence of both the Vogel temperature and fragility revealed a steplike transition around 4 nm pore size, which indicates a transition from a strong to a fragile behavior. The process with a relaxation rate in between the bulklike and the S-process (I-process) shows no dependence on the pore size. The agreement of the I-process with the behavior of a 5CB surface layer adsorbed on nonporous silica leads to the assignment of E7 molecules anchored at the outer surface of the microcrystals of the molecular sieves.

  16. Automatic Sieve-Shaker for Determining Soil Aggregate Stability and Dimensional Distribution Using a Vertical Oscillation System

    Directory of Open Access Journals (Sweden)

    Rosario Dell’Aquila

    Full Text Available The soil aggregate stability is determined generally by sifting the soil samples in water using a sieve-shaker (wet sieving. The Author has developed an original model of automatic sieve-shaker using a vertical oscillation system to the aim of an its possible use to determine the soil aggregate stability and dimensional distribution. The purpose of this note is to describe the construction and performance of the prototype currently used in the Laboratory for the Soil Structure Study of the ISAFOM – CNR. The proposed sieve-shaker, with the introduction of some innovations (protected by Italy Patent 0001332102, realizes the submersion and levelling of the soil samples using a lifter to support the containers with the water. With 6 workplaces it allows to process simultaneously up to 6 soil samples according to different test cycles. By means of the control panel it is possible to set up various determinations with the stroke of 3 cm and the oscillation frequency from 4 up to 80 oscillations per minute. The performance of the proposed sieve-shaker was verified with a technical test to verify the performance of the 6 workplaces to oscillation speed increasing up to 60 oscillations per minute and an agronomic test. The results have been submitted to analysis of variance considering the plots of the field from which have been taken the samples for repetitions and the six workplaces of the proposed sieve-shaker for experimental theses. The differences between the various workplaces have not been significant. This demonstrates that the behavior of the various workplaces is uniform. The dispersion in water at constant shaking time and increasing oscillation speed has evidenced a very significant inverse relation between the index of aggregate stability in water (IASW and number of oscillations per minute. This result demonstrates a constant performance of the proposed sieve-shaker to varying of the oscillation speed. The agnonomic test has demonstrated

  17. Automatic Sieve-Shaker for Determining Soil Aggregate Stability and Dimensional Distribution Using a Vertical Oscillation System

    Directory of Open Access Journals (Sweden)

    Rosario Dell’Aquila

    2007-12-01

    Full Text Available The soil aggregate stability is determined generally by sifting the soil samples in water using a sieve-shaker (wet sieving. The Author has developed an original model of automatic sieve-shaker using a vertical oscillation system to the aim of an its possible use to determine the soil aggregate stability and dimensional distribution. The purpose of this note is to describe the construction and performance of the prototype currently used in the Laboratory for the Soil Structure Study of the ISAFOM – CNR. The proposed sieve-shaker, with the introduction of some innovations (protected by Italy Patent 0001332102, realizes the submersion and levelling of the soil samples using a lifter to support the containers with the water. With 6 workplaces it allows to process simultaneously up to 6 soil samples according to different test cycles. By means of the control panel it is possible to set up various determinations with the stroke of 3 cm and the oscillation frequency from 4 up to 80 oscillations per minute. The performance of the proposed sieve-shaker was verified with a technical test to verify the performance of the 6 workplaces to oscillation speed increasing up to 60 oscillations per minute and an agronomic test. The results have been submitted to analysis of variance considering the plots of the field from which have been taken the samples for repetitions and the six workplaces of the proposed sieve-shaker for experimental theses. The differences between the various workplaces have not been significant. This demonstrates that the behavior of the various workplaces is uniform. The dispersion in water at constant shaking time and increasing oscillation speed has evidenced a very significant inverse relation between the index of aggregate stability in water (IASW and number of oscillations per minute. This result demonstrates a constant performance of the proposed sieve-shaker to varying of the oscillation speed. The agnonomic test has demonstrated

  18. Radiochemical and thermal studies of the cation-exchanged forms of synthetic zeolite Linde sieve A

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, S P [Saugar Univ. (India). Dept. of Chemistry

    1976-02-01

    The compositions of the cobalt and silver-exchanged forms of synthetic zeolite Sieve A have been determined by radiochemical and TGA studies and correspond to Co/sub 6/A.19.8H/sub 2/O and Ag/sub 12/..cap alpha... 20H/sub 2/O respectively (A=Al/sub 12/Si/sub 12/O/sub 48//sup 12/-). Heating of these zeolites inhibits their capacity for cation exchange and water absorption. No evidence of occluded NaAlO/sub 2/ has been found.

  19. Adsorption properties of a molecular 5 A sieve for 85Kr

    International Nuclear Information System (INIS)

    Wardaszko, T.; Nidecka, J.

    1978-01-01

    The enrichment processes which are necessary at low-level 85 Kr determinations in the atmospheric air require the knowledge of adsorption properties of appropriate sorbing agents, such as a molecular 5A sieve. Following low-temperature adsorption, under specified conditions, of known amounts of 85 Kr diluted in the air, desorption was carried out and then the 85 Kr content in the temperature fraction as well as their total volume were determined. Distribution curves for the above quantities in fractions are presented. (author)

  20. Air separation by pressure swing adsorption on a carbon molecular sieve

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, M M; Ruthven, D M; Raghaven, N S

    1986-01-01

    A simplified dynamic model for a PSA air separation process is developed based on linearized mass transfer rate expressions and binary Langmuir equilibrium. Constant pressure is assumed during adsorption and desorption steps but the variation in flow rate through the column due to adsorption is accounted for. The model predictions, using independently measured kinetic and equilibrium data are compared with experimental results obtained in a simple two-bed air separation PSA system packed with a carbon molecular sieve adsorbent. The model is shown to provide a good representation of the experimentally observed behavior over a wide range of conditions.

  1. Preparation and Characterization of High Silica Molecular Sieve from Rice Husk

    International Nuclear Information System (INIS)

    Hnaung Hnaung Win; Tin Tin Aye; Kyaw Myo Naing; Nyunt Wynn

    2008-03-01

    A mordenite type of hight silica molecular sieve with a formula composition Na32 (ALO2)32 (SiO2)176 192H2O having a high molar ratio of SiO2 /Al2O3 (5.4) with a percent yield of 98.76% has been prepared from synthesized zeolite NaY and glycolato silicate on the basis of hydrothermal condition.Zeolicate NaY and glycolato silicate were synthesized by using 98.34% purified silica which was extracted from rice husk.The characterizations with XRD, FT-IR, EDXRF,TG-DTA and SEM techniques were studied.

  2. Quantum mechanical analysis on faujasite-type molecular sieves by using fermi dirac statistics and quantum theory of dielectricity

    International Nuclear Information System (INIS)

    Jabeen, S.; Raza, S.M.; Ahmed, M.A.; Zai, M.Y.; Akbar, S.; Jafri, Y.Z.

    2012-01-01

    We studied Faujasite type molecular sieves by using Fermi Dirac statistics and the quantum theory of dielectricity. We developed an empirical relationship for quantum capacitance which follows an inverse Gaussian profile in the frequency range of 66 Hz - 3 MHz. We calculated quantum capacitance, sample crystal momentum, charge quantization and quantized energy of Faujasite type molecular sieves in the frequency range of 0.1 Hz - 10/sup 4/ MHz. Our calculations for diameter of sodalite and super-cages of Faujasite type molecular sieves are in agreement with experimental results reported in this manuscript. We also calculated quantum polarizability, quantized molecular field, orientational polarizability and deformation polarizability by using experimental results of Ligia Frunza etal. The phonons are over damped in the frequency range 0.1 Hz - 10 kHz and become a source for producing cages in the Faujasite type molecular sieves. Ion exchange recovery processes occur due to over damped phonon excitations in Faujasite type molecular sieves and with increasing temperatures. (author)

  3. Priming intelligent behavior: an elusive phenomenon.

    Directory of Open Access Journals (Sweden)

    David R Shanks

    Full Text Available Can behavior be unconsciously primed via the activation of attitudes, stereotypes, or other concepts? A number of studies have suggested that such priming effects can occur, and a prominent illustration is the claim that individuals' accuracy in answering general knowledge questions can be influenced by activating intelligence-related concepts such as professor or soccer hooligan. In 9 experiments with 475 participants we employed the procedures used in these studies, as well as a number of variants of those procedures, in an attempt to obtain this intelligence priming effect. None of the experiments obtained the effect, although financial incentives did boost performance. A Bayesian analysis reveals considerable evidential support for the null hypothesis. The results conform to the pattern typically obtained in word priming experiments in which priming is very narrow in its generalization and unconscious (subliminal influences, if they occur at all, are extremely short-lived. We encourage others to explore the circumstances in which this phenomenon might be obtained.

  4. Informal worker phenomenon in housing construction project

    Science.gov (United States)

    Wijayaningtyas, Maranatha; Sipan, Ibrahim; Lukiyanto, Kukuh

    2017-11-01

    The informal workers phenomenon on housing construction projects in Indonesia is different from workers in other sectors who would always request as permanent employees. Substantively, the informal workers are disinclined to be bound as permanent employees which different from the general labor paradigm. Hence, the objective of this study is to find out how the labour selection process, the factors that affected their performance, and the suitable wage system to achieve the target completion of housing construction project. The qualitative method is used to uncover and understand the meaning behind the phenomena (numina) of informal workers action and their influence on housing construction project which called phenomenological approach. Five informal workers and two project managers were selected as informants based on predetermined criteria with in-depth interviews. The results showed that the informal worker were more satisfied with the wage based on unit price while working in the housing construction project for the flexibility in working hours. In addition, the developer was also relieved because they only control the quality and the achievement of the project completion time which supported by informal worker leader. Therefore, these findings are beneficial for both of developer and government as policy maker to succeed the housing program in Indonesia.

  5. Virtual reality as a social phenomenon

    Directory of Open Access Journals (Sweden)

    Markova T. V.

    2018-05-01

    Full Text Available the article is devoted to the study of virtual reality as a social phenomenon. Through an appeal to the past, its genesis is analyzed, as well as its significance in modern realities. The latter is viewed from both a social and a personal point of view. Comparing the number of supporters of virtual communication with the number of people of conservative views, conclusions are drawn about the tendency to depart from the usual communication. It allows to assert that the problem of the termination of live communication is relevant to this day. Inferences allow us to assert that the problem of replacing real communication is different. After looking at the positive consequences, the introduction of the mind into virtual reality, it is affirmed that there are good sides to this action. Through analysis, the causes of entering the World Wide Web are generated. In conclusion, the question is raised about the need for virtual reality in everyday life, its problems, as well as the prospects for development.

  6. The keloid phenomenon: progress toward a solution.

    Science.gov (United States)

    Louw, Louise

    2007-01-01

    For centuries, keloids have been an enigma and despite considerable research to unravel this phenomenon no universally accepted treatment protocol currently exists. Historically, the etiology of keloids has been hypothesized by multiple different theories; however, a more contemporary view postulates a multifactoral basis for this disorder involving nutritional, biochemical, immunological, and genetic factors that play a role in this abnormal wound healing. Critical to the process of preventing or managing keloids is the need to locally control fibroblasts and their activities at the wound site. In recent years, considerable evidence has accumulated demonstrating the importance of fatty acids and bioactive lipids in health and disease, especially those involving inflammatory disorders or immune dysfunction. If hypertrophic scarring and keloid formation can be argued to have significant inflammatory histories, then it is possible to postulate a role for lipids in their etiology and potentially in their treatment. This report briefly visits past views and theories on keloid formation and treatment, and offers a theoretical rationale for considering adjuvant fatty acid therapy for keloid management. Sufficient scientific evidence in support of fatty acid strategies for the prevention and treatment of keloids currently exists, which offer opportunities to bridge the gap between the laboratory and the clinic. The intent of this paper is to serve as a basic guideline for researchers, nutritionists, and clinicians interested in keloids and to propose new directions for keloid management.

  7. Klein tunneling phenomenon with pair creation process

    Science.gov (United States)

    Wu, G. Z.; Zhou, C. T.; Fu, L. B.

    2018-01-01

    In this paper, we study the Klein tunneling phenomenon with electron-positron pair creation process. Pairs can be created from the vacuum by a supercritical single-well potential (for electrons). In the time region, the time-dependent growth pattern of the created pairs can be characterized by four distinct regimes which can be considered as four different statuses of the single well. We find that if positrons penetrate the single well by Klein tunneling in different statuses, the total number of the tunneling positrons will be different. If Klein tunneling begins at the initial stage of the first status i.e. when the sing well is empty, the tunneling process and the total number of tunneling positrons are similar to the traditional Klein tunneling case without considering the pair creation process. As the tunneling begins later, the total tunneling positron number increases. The number will finally settle to an asymptotic value when the tunneling begins later than the settling-down time t s of the single well which has been defined in this paper.

  8. The Sexting Phenomenon in Spanish Nursing Students.

    Science.gov (United States)

    Gutiérrez-Puertas, Vanesa; Gutiérrez-Puertas, Lorena; Aguilera-Manrique, Gabriel; Baños-Martín, María Del Mar; Granados-Gámez, Genoveva; Márquez-Hernández, Verónica V

    2017-08-01

    One of the adverse effects arising among young people who engage in various social practices is the phenomenon of sexting. Sexting involves the production and delivery of sexual content voluntarily and freely and, in many cases, without the consent of the recipient. The aim of this study was to describe the presence of sexting in undergraduate students at the College of Nursing of the University of Almeria in Spain. It is a descriptive cross-sectional quantitative study. A total of 105 undergraduate nursing students completed the sexuality and technology questionnaire. The questionnaire consists of seven dimensions with 59 items. Depending on size, statistically significant differences between the use of social networks and the dimension "sexting actions completed" and the dimension "position on statements about sexting" were found. No statistically significant differences between gender and the practice of sexting were found. The three main reasons for sexting match in both genders, these being "to draw attention," "as a sexy gift," and "to feel sexy." Nursing students associated behaviors to show sexting, being a standard practice, common in both genders. Future research should consider the possible influence of this behavior on future professionals and on the field of nursing.

  9. The Outsider Phenomenon in Teenage Groups

    Directory of Open Access Journals (Sweden)

    Kuminskya E.A.

    2017-08-01

    Full Text Available The article is devoted to the problem of outsidership in groups of younger and older adolescents. We assumed that there are personal qualities that distinguish outsiders from other students, which allows us to speak of outsidership as a separate group and personal phenomenon. The study involved 246 students of Moscow schools of younger and older adolescents, 60 of whom took an outsider position in the group. To test the hypothesis were used: a personal questionnaire for adolescents HSPQ (R. Cattell, questionnaire Emin to determine the level of emotional intelligence (D.V. Lyusin, the technique of " Suggestibility " (O.E. Rybakov. To identify statistical differences, the Student's t-test and the Mann-Whitney U-test were used, p ≤ 0.05. The results of the study showed that outsiders of adolescence are indeed characterized by a number of personal characteristics that distinguish them from their peers. Differences in personal characteristics of outsiders at different stages of adolescence have their own characteristics.

  10. Lung tissue mechanics as an emergent phenomenon.

    Science.gov (United States)

    Suki, Béla; Bates, Jason H T

    2011-04-01

    The mechanical properties of lung parenchymal tissue are both elastic and dissipative, as well as being highly nonlinear. These properties cannot be fully understood, however, in terms of the individual constituents of the tissue. Rather, the mechanical behavior of lung tissue emerges as a macroscopic phenomenon from the interactions of its microscopic components in a way that is neither intuitive nor easily understood. In this review, we first consider the quasi-static mechanical behavior of lung tissue and discuss computational models that show how smooth nonlinear stress-strain behavior can arise through a percolation-like process in which the sequential recruitment of collagen fibers with increasing strain causes them to progressively take over the load-bearing role from elastin. We also show how the concept of percolation can be used to link the pathologic progression of parenchymal disease at the micro scale to physiological symptoms at the macro scale. We then examine the dynamic mechanical behavior of lung tissue, which invokes the notion of tissue resistance. Although usually modeled phenomenologically in terms of collections of springs and dashpots, lung tissue viscoelasticity again can be seen to reflect various types of complex dynamic interactions at the molecular level. Finally, we discuss the inevitability of why lung tissue mechanics need to be complex.

  11. Empirical Study on the Creative Accounting Phenomenon

    Directory of Open Access Journals (Sweden)

    Cernusca Lucian

    2016-06-01

    Full Text Available The present study aims to analyze the accounting professionals’ point of view as opposed to the students and master students’ one, regarding the creative accounting phenomenon existence and manifestation forms. In order to accomplish this objective, there has been used the poll/investigation, as a research method and the questionnaire, as a research instrument. Within the study, there is suggested the testing of more hypotheses that contribute to the clarifying of the aspects wished to be analyzed through the research. These hypotheses’ acceptance or rejection is based on the „chi-square“ (Karl Pearson statistical test and rank ordering method. Trying to elaborate a global conclusion of the questionnaire, there could be noticed the fact that over 50% from the questioned accounting students are not tempted to use the creative accounting practices and techniques in order to optimize the taxation without breaking the actual law regulations. At the opposite side, more than a half from the questioned accounting professionals would use these practices without breaking the law regulations that lead to the taxation’s optimization. The creative accounting has a negative connotation if the accurate image of the financial position and of the performance is not targeted because it represents the essential factor for elaborating and grounding the accounting policies. However, the positive side of the creative accounting is not excluded, given that one appeals to the „fair“ professional judgment of the accounting professionals and to the good faith of managers.

  12. Mapping The Phenomenon Of Students’ Entrepreneurial Intention

    Directory of Open Access Journals (Sweden)

    Yud Buana

    2016-09-01

    Full Text Available This research mapped the phenomena that occured in students who are taking classes entrepreneurship that was limited by entrepreneurial knowledge, personal attitude, social norms and self-efficacy. Using descriptive statistics on the answers of 794 respondents, who were students of Bina Nusantara University, produced a variety of results. Based on entrepreneurial knowledge, students still felt hesitant to be able to start and run the entrepreneurial process. On the other hand, self-efficacy and personal attitude reflect a positive thing associated, while the support of family and the environment around where they livevalued invariety. Although this research discovered phenomenon using all the attributes having impacts on entrepreneurship intention, potential students who are properly trained have a probability of playing a leading role in this regard. The benefits that can be expected from this research are useful in identifying suitable students for any entrepreneurial activity in the future with the support of educational institutions, families, and the government as a whole to form the atmosphere of an entrepreneurial culture.

  13. Evolution as a molecular cooperative phenomenon

    International Nuclear Information System (INIS)

    Chela-Flores, J.

    1991-06-01

    We discuss an hypothesis according to which microscopic mechanisms due to cooperation, at the molecular level, may have been key factors in the evolution of life on Earth. We view our hypothesis as a natural extension to the molecular level of viewing cooperation (symbiosis) as an evolutionary driving force; this does not restrict the interpretation of the evolutionary process to be the result of slow accumulation of mutations in the DNA. Some evidence supporting this hypothesis is discussed: (a) The Salam enhancement factor. This molecular phenomenon was recently introduced in order to understand the bases of the first unifying principle of biochemistry, namely that transcription of all known genes in prokaryotes, protists, metazoan, and metaphytes are translated into L-amino acids, except for some bacterial membrane proteins. (b) The role that cooperative phenomena may have played in the origin of evolution itself, i.e., in the resolution of Sagan's ultraviolet paradox. (c) The relationship between evolution and the constraints imposed by embryonic development. This is considered from the point of view of molecular cooperative phenomena. (author). Refs

  14. Priming Intelligent Behavior: An Elusive Phenomenon

    Science.gov (United States)

    Shanks, David R.; Newell, Ben R.; Lee, Eun Hee; Balakrishnan, Divya; Ekelund, Lisa; Cenac, Zarus; Kavvadia, Fragkiski; Moore, Christopher

    2013-01-01

    Can behavior be unconsciously primed via the activation of attitudes, stereotypes, or other concepts? A number of studies have suggested that such priming effects can occur, and a prominent illustration is the claim that individuals' accuracy in answering general knowledge questions can be influenced by activating intelligence-related concepts such as professor or soccer hooligan. In 9 experiments with 475 participants we employed the procedures used in these studies, as well as a number of variants of those procedures, in an attempt to obtain this intelligence priming effect. None of the experiments obtained the effect, although financial incentives did boost performance. A Bayesian analysis reveals considerable evidential support for the null hypothesis. The results conform to the pattern typically obtained in word priming experiments in which priming is very narrow in its generalization and unconscious (subliminal) influences, if they occur at all, are extremely short-lived. We encourage others to explore the circumstances in which this phenomenon might be obtained. PMID:23637732

  15. Vacuum phenomenon in the metatarsophalangeal joint of a horse

    International Nuclear Information System (INIS)

    Specht, T.E.; Poulos, P.W.; Metcalf, M.R.; Robertson, I.D.

    1990-01-01

    Vacuum phenomenon was induced inadvertently during radiographic examination of a metatarsophalangeal joint of a lame horse. The phenomenon was recreated in a sound horse when a metacarpophalangeal joint was radiographed in a stress-flexed position. Distraction of apposing articular surfaces may induce the vacuum phenomenon, which could result in misdiagnosis of an osteochondral defect or fracture

  16. 21 CFR 862.1230 - Cyclic AMP test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cyclic AMP test system. 862.1230 Section 862.1230....1230 Cyclic AMP test system. (a) Identification. A cyclic AMP test system is a device intended to measure the level of adenosine 3′, 5′-monophosphate (cyclic AMP) in plasma, urine, and other body fluids...

  17. Application of computational fluid dynamics for the simulation of cryogenic molecular sieve bed absorber of hydrogen isotopes recovery system for Indian LLCB-TBM

    Energy Technology Data Exchange (ETDEWEB)

    Gayathri Devi, V.; Sircar, A.; Sarkar, B. [Institute of Plasma Research, Bhat, Gandhinagar, Gujarar (India)

    2015-03-15

    One of the most challenging tasks in the design of the fuel cycle system lies in the effective design of Tritium Extraction System (TES) which involves proper extraction and purification of tritium in the fuel cycle of the fusion reactor. Indian Lead Lithium cooled Ceramic Breeder Test Blanket Module (LLCB-TBM) would extract hydrogen isotopes through Cryogenic Molecular Sieve Bed (CMSB) adsorber system. A prototype Hydrogen Isotopes Recovery System (HIRS) is being developed to validate the concepts for tritium extraction by adsorption mass transfer mechanism. In this study, a design model has been developed and analyzed to simulate the adsorption mass transfer kinetics in a fixed bed adsorption column. The simulation leads primarily to effective design of HIRS, which is a state-of-the-art technology. The paper describes the process simulation approach and the results of Computational Fluid Dynamics (CFD) analysis. The effects of different operating conditions are studied to investigate their influence on the hydrogen isotopes adsorption capacity. The results of the present simulation study would be used to understand the best optimized transport phenomenon before realizing the TES as a system for LLCB-TBM. (authors)

  18. A suspicious reason for Raynaud's phenomenon: Intrauterine device.

    Science.gov (United States)

    Diken, Adem I; Yalçınkaya, Adnan; Aksoy, Eray; Yılmaz, Seyhan; Çağlı, Kerim

    2015-06-01

    Primary Raynaud's phenomenon may be insistent in patients under medical therapy, and intrauterine devices may be an unnoticed reason in these patients. Fluctuations in female sex hormone status were reported to be associated with the emergence of primary Raynaud's phenomenon symptoms. The use of intrauterine devices was not reported to be associated with Raynaud's phenomenon previously. Intrauterine device may stimulate vascular hyperactivity regarding hormonal or unknown mechanisms that result in Raynaud's phenomenon. We present a postmenopausal patient who complained of primary Raynaud's phenomenon symptoms and had recovery after the removal of her copper intrauterine device. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  19. Cognitive approach in studying of entrepreneur phenomenon

    Directory of Open Access Journals (Sweden)

    Kulakovsky T.Yu.

    2017-06-01

    Full Text Available The research indicates that there is no prospect of searching specific entrepreneurial traits that are necessary for conducting successful entrepreneurial activity. It is pointed on the impossibility to fully explain the negative state of domestic business exclusively by the influence of environmental factors. The paper points on the necessity of concentrating the scientific search on the cognitive features of personality, as factors that contribute to success of entrepreneurial activities. It is revealed that the decision-making process directed on problem-solving in entrepreneurial activity, from an entrepreneurial idea to obtaining an appropriate result, cannot be algorithmized. The author points out on the insufficiency of attempts to model cognitive processes of entrepreneurs, in which their cognitive activity is regarded as an information processing system that resembles a computer. The results obtained in the framework of the cognitive approach in studying the phenomenon of the entrepreneur are analyzed. Particular emphasis is placed on the features of heuristics and cognitive biases. It is stated that the high levels of uncertainty, novelty, time deficit, information overload and emotional tension facilitate influence of cognitive biases on the cognitive processes of the entrepreneur. The role of «availability heuristic», «anchoring and adjustment heuristic», «confirmation bias», «hindsight bias» and self-efficacy in making decisions about starting an entrepreneurial activity are considered. The article points to the role of «belief in the law of small numbers» and the illusion of control in establishing optimistic bias (overly positive self-esteem, excessive optimism about future plans and events that lead to reducing the subjective perception of entrepreneurial risk.

  20. Electron string phenomenon: physics and use

    Science.gov (United States)

    Donets, Evgeny D.

    2004-01-01

    Electron string phenomenon arises as a result of phase transition of a state of multiply reflected electron beam to this new discovered state of one component electron plasma and can be easily observed in the reflex mode of EBIS operation. The transition goes via a strong instability, which causes considerable electron energy spread, which in its turn suppresses the instability. Electron string state is a stationary state of hot pure electron plasma, which is heated by injected electron beam and cooled because of electron loses. Electron string is quiet in broad regions of experimental parameters, so that it is used for confinement and ionization of positive ions by electron impact to highly charge states similar to electron beams in EBIS. Application of electron strings instead of electron beams for ion production allows to save about 99% of electric power of electron beam and simultaneously to improve reliability of an ion source considerably. The JINR EBIS `Krion-2' in the string mode of operation is used for production of N7+, Ar16+ and Fe24+ ion beams and their acceleration to relativistic energies on the facility of the JINR super conducting one turn injection synchrotron `Nuklotron'. The tubular electron string possibly can exist and it is under study now theoretically and experiments are prepared now. Estimations show that a Tubular Electron String Ion Source (TESIS) could have up to three orders of magnitude higher ion output then a Linear one (LESIS). In frames of nuclear astrophysics electron strings can be used for research of fusion nuclear reactions at low energies in conditions when both beam and target nuclei do not carry orbital electrons. The project NARITA — Nuclear Astrophysics Researches in an Ion Trap Apparatus is proposed. Polarization effects also can be studied.

  1. Electron string phenomenon: physics and use

    International Nuclear Information System (INIS)

    Donets, Evgeny D

    2004-01-01

    Electron string phenomenon arises as a result of phase transition of a state of multiply reflected electron beam to this new discovered state of one component electron plasma and can be easily observed in the reflex mode of EBIS operation. The transition goes via a strong instability, which causes considerable electron energy spread, which in its turn suppresses the instability. Electron string state is a stationary state of hot pure electron plasma, which is heated by injected electron beam and cooled because of electron loses. Electron string is quiet in broad regions of experimental parameters, so that it is used for confinement and ionization of positive ions by electron impact to highly charge states similar to electron beams in EBIS. Application of electron strings instead of electron beams for ion production allows to save about 99% of electric power of electron beam and simultaneously to improve reliability of an ion source considerably. The JINR EBIS 'Krion-2' in the string mode of operation is used for production of N 7+ , Ar 16+ and Fe 24+ ion beams and their acceleration to relativistic energies on the facility of the JINR super conducting one turn injection synchrotron 'Nuklotron'. The tubular electron string possibly can exist and it is under study now theoretically and experiments are prepared now. Estimations show that a Tubular Electron String Ion Source (TESIS) could have up to three orders of magnitude higher ion output then a Linear one (LESIS). In frames of nuclear astrophysics electron strings can be used for research of fusion nuclear reactions at low energies in conditions when both beam and target nuclei do not carry orbital electrons. The project NARITA - Nuclear Astrophysics Researches in an Ion Trap Apparatus is proposed. Polarization effects also can be studied

  2. Shifted identical bands: A new phenomenon

    International Nuclear Information System (INIS)

    Jones, E.F.; Lima, A.P. de; Gore, P.M.; Hamilton, J.H.; Ramayya, A.V.; Dodder, R.S.; Kormicki, J.; Hwang, J.K.; Beyer, C.J.; Zhang, X.Q.; Zhu, S.J.; Ter-Akopian, G.M.; Oganessian, Yu.Ts.; Daniel, A.V.; Rasmussen, J.O.; Lee, I.Y.; Cole, J.D.; Drigert, M.W.; Ma, W.-C.

    2001-01-01

    The levels in 162 Gd were identified in spontaneous fission studies. Its transition energies are remarkably similar to those in 160 Gd. From that work, an analysis of yrast bands in even-even proton to neutron-rich Ba to Pb nuclei led to the discovery of a new phenomenon, shifted identical bands (SIB). SIBs are yrast bands in neighboring nuclei (a, b) with moments of inertia which are identical when shifted by a constant amount κ, so J 1a (1 + κ) = J 1b , from 2 + to 8 + and higher to 16 + . Out of over 700 comparisons, 55 SIBs were found from stable to the most neutron-rich Ce-W nuclei with |κ-bar| between 1.5% and 13%, where the spread in κ is less than ± 1%, and only four identical bands (κ-bar congruent with 0). As examples, we found for 158 Sm- 160 Gd, κ-bar (-3.2 +0.1 -0.2 )% (where the ± is the total spread in κ from -3.1 to -3.4); 156 Nd- 160 Gd, (-10.6 +0.4 -0.2 )%; 158 Sm- 160 Sm, (3.4 +0.5 -0.3 )%. The J 1 values were fitted to a variable moment of inertia model with parameters J 0 and C whose values correlate with the SIB J 1 values. The SIBs are not correlated either with deformation or with the N p N n product of the IBA model

  3. Weight-based discrimination: an ubiquitary phenomenon?

    Science.gov (United States)

    Sikorski, C; Spahlholz, J; Hartlev, M; Riedel-Heller, S G

    2016-02-01

    Despite strong indications of a high prevalence of weight-related stigmatization in individuals with obesity, limited attention has been given to the role of weight discrimination in examining the stigma obesity. Studies, up to date, rely on a limited basis of data sets and additional studies are needed to confirm the findings of previous studies. In particular, data for Europe are lacking, and are needed in light of a recent ruling of the European Court of Justice that addressed weight-based discrimination. The data were derived from a large representative telephone survey in Germany (n=3003). The dependent variable, weight-based discrimination, was assessed with a one-item question. The lifetime prevalence of weight discrimination across different sociodemographic variables was determined. Logistic regression models were used to assess the association of independent and dependent variables. A sub-group analysis was conducted analyzing all participants with a body mass index ⩾25 kg m(-)(2). The overall prevalence of weight-based discrimination was 7.3%. Large differences, however, were observed regarding weight status. In normal weight and overweight participants the prevalence was 5.6%, but this number doubled in participants with obesity class I (10.2%), and quadrupled in participants with obesity class II (18.7%) and underweight (19.7%). In participants with obesity class III, every third participant reported accounts of weight-based discrimination (38%). In regression models, after adjustment, the associations of weight status and female gender (odds ratio: 2.59, PDiscrimination seems to be an ubiquitary phenomenon at least for some groups that are at special risk, such as heavier individuals and women. Our findings therefore emphasize the need for research and intervention on weight discrimination among adults with obesity, including anti-discrimination legislation.

  4. The Trump phenomenon: An explanation from sociophysics

    Science.gov (United States)

    Galam, Serge

    2017-04-01

    The Trump phenomenon is argued to depart from current populist rise in Europe. According to a model of opinion dynamics from sociophysics the machinery of Trump’s amazing success obeys well-defined counter-intuitive rules. Therefore, his success was in principle predictable from the start. The model uses local majority rule arguments and obeys a threshold dynamics. The associated tipping points are found to depend on the leading collective beliefs, cognitive biases and prejudices of the social group which undertakes the public debate. And here comes the open sesame of the Trump campaign, which develops along two successive steps. During a first moment, Trump’s statement produces a majority of voters against him. But at the same time, according to the model the shocking character of the statement modifies the prejudice balance. In case the prejudice is present even being frozen among voters, the tipping point is lowered at Trump’s benefit. Nevertheless, although the tipping point has been lowered by the activation of frozen prejudices it is instrumental to preserve enough support from openly prejudiced people to be above the threshold. Then, as infuriated voters launch intense debate, occurrence of ties will drive progressively hostile people to shift their voting intention without needing to endorse the statement which has infuriated them. The ongoing debate does drive towards a majority for Trump. The possible Trump victory at November Presidential election is discussed. In particular, the model shows that to eventually win the Presidential election, Trump must not modify his past shocking attitude but to appeal to a different spectrum of frozen prejudices, which are common to both Democrats and Republicans.

  5. Application and improvement of reciprocating-sieve plate extraction column in natural uranium extraction and purification process

    International Nuclear Information System (INIS)

    Wang Xuejun; Li Linyan; Liu Jing; Liu Xin; Yang Lifeng; Xiao Shaohua; Liu Hao

    2013-01-01

    Reciprocating-sieve plate extraction column is commonly used in the extraction process. Optimization and application were conducted successfully via production practice in some chemical and pharmaceutical plants, and good results are obtained while it is applied in the natural uranium extraction and purification process. The key component of reciprocating-sieve plate extraction column is gear-drive equipment in which drive motor serves as its core. Hence, it is important to select appropriate mode of speed regulation. In this paper, the principle and performance of several mode of speed regulation are compared. Both electromagnetic slip and frequency speed-regulation can be applied in general industrial process, but frequency speed-regulation with low energy cost can be used in wider operating range. The application of frequency speed-regulation mode used in reciprocating-sieve plate extraction column will increase the convenience and stability of natural uranium extraction and purification process. (authors)

  6. Summary different routes for procurement of molecular sieves type AL-SBA-15

    International Nuclear Information System (INIS)

    Figueiroa, D.S.; Santos, J.O.P.N.; Medeiros, C.D.; Sousa, B.V.

    2012-01-01

    The search for new materials to assist industrial development, especially in the chemical industry has been growing more and more. Molecular sieves are great examples of these materials that aim the improvement of various chemical processes. The present work aimed to synthesize the molecular sieve Al-SBA-15 by two different synthesis procedures. In procedure A was used a temperature of 40°C for 24 hours during stirring process. For B process the stirring procedure was done at room temperature. The molar composition of reactants was: 1.0 SiO 2 : 0.04 Al 2 O 3 :0.0168 EO 20 PO 70 EO 20 : 5.85 HCl: 160 H 2 O. The pH of the reaction gel was adjusted to 7 and after the gel was putted under 100 deg C for 48 hours for the heat treatment. Then the sample was calcined under flowing air at 500° C for 6 hours. By techniques such as XRD and SEM, it was confirmed the formation of the hexagonal mesoporous structure, with an orderly distribution of its pores, also indicating the successful incorporation of aluminum into the hexagonal structure of the catalyst support. (author)

  7. Combining sieving and washing, a way to treat MSWI boiler fly ash.

    Science.gov (United States)

    De Boom, Aurore; Degrez, Marc

    2015-05-01

    Municipal Solid Waste Incineration (MSWI) fly ashes contain some compounds that could be extracted and valorised. A process based on wet sieving and washing steps has been developed aiming to reach this objective. Such unique combination in MSWI fly ash treatment led to a non-hazardous fraction from incineration fly ashes. More specifically, MSWI Boiler Fly Ash (BFA) was separately sampled and treated. The BFA finer particles (13wt%) were found to be more contaminated in Pb and Zn than the coarser fractions. After three washing steps, the coarser fractions presented leaching concentrations acceptable to landfill for non-hazardous materials so that an eventual subsequent valorisation may be foreseen. At the contrary, too much Pb leached from the finest particles and this fraction should be further treated. Wet sieving and washing permit thus to reduce the leachability of MSWI BFA and to concentrate the Pb and Zn contamination in a small (in particle size and volume) fraction. Such combination would therefore constitute a straightforward and efficient basis to valorise coarse particles from MSWI fly ashes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Fabrication variables affecting the structure and properties of supported carbon molecular sieve membranes for hydrogen separation

    KAUST Repository

    Briceñ o, Kelly; Montané , Daniel; Garcia-Valls, Ricard; Iulianelli, Adolfo; Basile, Angelo

    2012-01-01

    A high molecular weight polyimide (Matrimid) was used as a precursor for fabricating supported carbon molecular sieve membranes without crack formation at 550-700°C pyrolysis temperature. A one-step polymer (polyimide) coating method as precursor of carbon layer was used without needing a prior modification of a TiO 2 macroporous support. The following fabrication variables were optimized and studied to determine their effect on the carbon structure: polymeric solution concentration, solvent extraction, heating rate and pyrolysis temperature. Two techniques (Thermogravimetric analysis and Raman spectroscopy) were used to determine these effects on final carbon structure. Likewise, the effect of the support was also reported as an additional and important variable in the design of supported carbon membranes. Atomic force microscopy and differential scanning calorimetry quantified the degree of influence. Pure gas permeation tests were performed using CH 4, CO, CO 2 and H 2. The presence of a molecular sieving mechanism was confirmed after defects were plugged with PDMS solution at 12wt%. Gas selectivities higher than Knudsen theoretical values were reached with membranes obtained over 650°C, showing as best values 4.46, 4.70 and 10.62 for H 2/N 2, H 2/CO and H 2/CH 4 ratio, respectively. Permeance values were over 9.82×10 -9mol/(m 2Pas)during pure hydrogen permeation tests. © 2012 Elsevier B.V.

  9. Fabrication variables affecting the structure and properties of supported carbon molecular sieve membranes for hydrogen separation

    KAUST Repository

    Briceño, Kelly

    2012-10-01

    A high molecular weight polyimide (Matrimid) was used as a precursor for fabricating supported carbon molecular sieve membranes without crack formation at 550-700°C pyrolysis temperature. A one-step polymer (polyimide) coating method as precursor of carbon layer was used without needing a prior modification of a TiO 2 macroporous support. The following fabrication variables were optimized and studied to determine their effect on the carbon structure: polymeric solution concentration, solvent extraction, heating rate and pyrolysis temperature. Two techniques (Thermogravimetric analysis and Raman spectroscopy) were used to determine these effects on final carbon structure. Likewise, the effect of the support was also reported as an additional and important variable in the design of supported carbon membranes. Atomic force microscopy and differential scanning calorimetry quantified the degree of influence. Pure gas permeation tests were performed using CH 4, CO, CO 2 and H 2. The presence of a molecular sieving mechanism was confirmed after defects were plugged with PDMS solution at 12wt%. Gas selectivities higher than Knudsen theoretical values were reached with membranes obtained over 650°C, showing as best values 4.46, 4.70 and 10.62 for H 2/N 2, H 2/CO and H 2/CH 4 ratio, respectively. Permeance values were over 9.82×10 -9mol/(m 2Pas)during pure hydrogen permeation tests. © 2012 Elsevier B.V.

  10. The experiment of the elemental mercury was removed from natural gas by 4A molecular sieve

    Science.gov (United States)

    Jiang, Cong; Chen, Yanhao

    2018-04-01

    Most of the world's natural gas fields contain elemental mercury and mercury compounds, and the amount of mercury in natural gas is generally 1μg/m3 200μg/m3. This paper analyzes the mercury removal principle of chemical adsorption process, the characteristics and application of mercury removal gent and the factors that affect the efficiency of mercury removal. The mercury in the natural gas is adsorbed by the mercury-silver reaction of the 4 molecular sieve after the manned treatment. The limits for mercury content for natural gas for different uses and different treatment processes are also different. From the environmental protection, safety and other factors, it is recommended that the mercury content of natural gas in the pipeline is less than 28μg / m3, and the mercury content of the raw material gas in the equipment such as natural gas liquefaction and natural gas condensate recovery is less than 0.01μg/m3. This paper mainly analyzes the existence of mercury in natural gas, and the experimental research process of using 4A molecular sieve to absorb mercury in natural gas.

  11. Sieve-based device for MALDI sample preparation. III. Its power for quantitative measurements.

    Science.gov (United States)

    Molin, Laura; Cristoni, Simone; Seraglia, Roberta; Traldi, Pietro

    2011-02-01

    The solid sample inhomogeneity is a weak point of traditional MALDI deposition techniques that reflects negatively on quantitative analysis. The recently developed sieve-based device (SBD) sample deposition method, based on the electrospraying of matrix/analyte solutions through a grounded sieve, allows the homogeneous deposition of microcrystals with dimensions smaller than that of the laser spot. In each microcrystal the matrix/analyte molar ratio can be considered constant. Then, by irradiating different portions of the microcrystal distribution an identical response is obtained. This result suggests the employment of SBD in the development of quantitative procedures. For this aim, mixtures of different proteins of known molarity were analyzed, showing a good relationship between molarity and intensity ratios. This behaviour was also observed in the case of proteins with quite different ionic yields. The power of the developed method for quantitative evaluation was also tested by the measurement of the abundance of IGPP[Oxi]GPP[Oxi]GLMGPP (m/z 1219) present in the collagen-α-5(IV) chain precursor, differently expressed in urines from healthy subjects and diabetic-nephropathic patients, confirming its overexpression in the presence of nephropathy. The data obtained indicate that SBD is a particularly effective method for quantitative analysis also in biological fluids of interest. Copyright © 2011 John Wiley & Sons, Ltd.

  12. Ricinus communis cyclophilin: functional characterisation of a sieve tube protein involved in protein folding.

    Science.gov (United States)

    Gottschalk, Maren; Dolgener, Elmar; Xoconostle-Cázares, Beatriz; Lucas, William J; Komor, Ewald; Schobert, Christian

    2008-09-01

    The phloem translocation stream of the angiosperms contains a special population of proteins and RNA molecules which appear to be produced in the companion cells prior to being transported into the sieve tube system through the interconnecting plasmodesmata. During this process, these non-cell-autonomous proteins are thought to undergo partial unfolding. Recent mass spectroscopy studies identified peptidyl-prolyl cis-trans isomerase (PPIases) as potential molecular chaperones functioning in the phloem translocation stream (Giavalisco et al. 2006). In the present study, we describe the cloning and characterisation of a castor bean phloem cyclophilin, RcCYP1 that has high peptidyl-prolyl cis-trans isomerase activity. Equivalent enzymatic activity was detected with phloem sap or purified recombinant (His)(6)-tagged RcCYP1. Mass spectrometry analysis of proteolytic peptides, derived from a 22 kDa band in HPLC-fractionated phloem sap, immunolocalisation studies and Western analysis of proteins extracted from castor bean tissues/organs indicated that RcCYP1 is an abundant protein in the companion cell-sieve element complex. Microinjection experiments established that purified recombinant (His)(6)-RcCYP1 can interact with plasmodesmata to both induce an increase in size exclusion limit and mediate its own cell-to-cell trafficking. Collectively, these findings support the hypothesis that RcCYP1 plays a role in the refolding of non-cell-autonomous proteins after their entry into the phloem translocation stream.

  13. Morphine biosynthesis in opium poppy involves two cell types: sieve elements and laticifers.

    Science.gov (United States)

    Onoyovwe, Akpevwe; Hagel, Jillian M; Chen, Xue; Khan, Morgan F; Schriemer, David C; Facchini, Peter J

    2013-10-01

    Immunofluorescence labeling and shotgun proteomics were used to establish the cell type-specific localization of morphine biosynthesis in opium poppy (Papaver somniferum). Polyclonal antibodies for each of six enzymes involved in converting (R)-reticuline to morphine detected corresponding antigens in sieve elements of the phloem, as described previously for all upstream enzymes transforming (S)-norcoclaurine to (S)-reticuline. Validated shotgun proteomics performed on whole-stem and latex total protein extracts generated 2031 and 830 distinct protein families, respectively. Proteins corresponding to nine morphine biosynthetic enzymes were represented in the whole stem, whereas only four of the final five pathway enzymes were detected in the latex. Salutaridine synthase was detected in the whole stem, but not in the latex subproteome. The final three enzymes converting thebaine to morphine were among the most abundant active latex proteins despite a limited occurrence in laticifers suggested by immunofluorescence labeling. Multiple charge isoforms of two key O-demethylases in the latex were revealed by two-dimensional immunoblot analysis. Salutaridine biosynthesis appears to occur only in sieve elements, whereas conversion of thebaine to morphine is predominant in adjacent laticifers, which contain morphine-rich latex. Complementary use of immunofluorescence labeling and shotgun proteomics has substantially resolved the cellular localization of morphine biosynthesis in opium poppy.

  14. Method for Determining the Activation Energy Distribution Function of Complex Reactions by Sieving and Thermogravimetric Measurements.

    Science.gov (United States)

    Bufalo, Gennaro; Ambrosone, Luigi

    2016-01-14

    A method for studying the kinetics of thermal degradation of complex compounds is suggested. Although the method is applicable to any matrix whose grain size can be measured, herein we focus our investigation on thermogravimetric analysis, under a nitrogen atmosphere, of ground soft wheat and ground maize. The thermogravimetric curves reveal that there are two well-distinct jumps of mass loss. They correspond to volatilization, which is in the temperature range 298-433 K, and decomposition regions go from 450 to 1073 K. Thermal degradation is schematized as a reaction in the solid state whose kinetics is analyzed separately in each of the two regions. By means of a sieving analysis different size fractions of the material are separated and studied. A quasi-Newton fitting algorithm is used to obtain the grain size distribution as best fit to experimental data. The individual fractions are thermogravimetrically analyzed for deriving the functional relationship between activation energy of the degradation reactions and the particle size. Such functional relationship turns out to be crucial to evaluate the moments of the activation energy distribution, which is unknown in terms of the distribution calculated by sieve analysis. From the knowledge of moments one can reconstruct the reaction conversion. The method is applied first to the volatilization region, then to the decomposition region. The comparison with the experimental data reveals that the method reproduces the experimental conversion with an accuracy of 5-10% in the volatilization region and of 3-5% in the decomposition region.

  15. Slower phloem transport in gymnosperm trees can be attributed to higher sieve element resistance.

    Science.gov (United States)

    Liesche, Johannes; Windt, Carel; Bohr, Tomas; Schulz, Alexander; Jensen, Kaare H

    2015-04-01

    In trees, carbohydrates produced in photosynthesizing leaves are transported to roots and other sink organs over distances of up to 100 m inside a specialized transport tissue, the phloem. Angiosperm and gymnosperm trees have a fundamentally different phloem anatomy with respect to cell size, shape and connectivity. Whether these differences have an effect on the physiology of carbohydrate transport, however, is not clear. A meta-analysis of the experimental data on phloem transport speed in trees yielded average speeds of 56 cm h(-1) for angiosperm trees and 22 cm h(-1) for gymnosperm trees. Similar values resulted from theoretical modeling using a simple transport resistance model. Analysis of the model parameters clearly identified sieve element (SE) anatomy as the main factor for the significantly slower carbohydrate transport speed inside the phloem in gymnosperm compared with angiosperm trees. In order to investigate the influence of SE anatomy on the hydraulic resistance, anatomical data on SEs and sieve pores were collected by transmission electron microscopy analysis and from the literature for 18 tree species. Calculations showed that the hydraulic resistance is significantly higher in the gymnosperm than in angiosperm trees. The higher resistance is only partially offset by the considerably longer SEs of gymnosperms. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Carbon molecular sieve membranes derived from Matrimid® polyimide for nitrogen/methane separation

    KAUST Repository

    Ning, Xue

    2014-01-01

    A commercial polyimide, Matrimid® 5218, was pyrolyzed under an inert argon atmosphere to produce carbon molecular sieve (CMS) dense film membranes for nitrogen/methane separation. The resulting CMS dense film separation performance was evaluated using both pure and mixed N2/CH4 permeation tests. The effects of final pyrolysis temperature on N 2/CH4 separation are reported. The separation performance of all CMS dense films significantly exceeds the polymer precursor dense film. The CMS dense film pyrolyzed at 800 C shows very attractive separation performance that surpasses the polymer membrane upper bound line, with N 2 permeability of 6.8 Barrers and N2/CH4 permselectivity of 7.7 from pure gas permeation, and N2 permeability of 5.2 Barrers and N2/CH4 permselectivity of 6.0 from mixed gas permeation. The temperature dependences of permeabilities, sorption coefficients, and diffusion coefficients of the membrane were studied, and the activation energy for permeation and diffusion, as well as the apparent heats of sorption are reported. The high permselectivity of this dense film is shown to arise from a significant entropic contribution in the diffusion selectivity. The study shows that the rigid \\'slit-shaped\\' CMS pore structure can enable a strong molecular sieving effect to effectively distinguish the size and shape difference between N2 and CH4. © 2013 Elsevier Ltd. All rights reserved.

  17. Comparative Study of Phase Transformation in Single-Crystal Germanium during Single and Cyclic Nanoindentation

    Directory of Open Access Journals (Sweden)

    Koji Kosai

    2017-11-01

    Full Text Available Single-crystal germanium is a semiconductor material which shows complicated phase transformation under high pressure. In this study, new insight into the phase transformation of diamond-cubic germanium (dc-Ge was attempted by controlled cyclic nanoindentation combined with Raman spectroscopic analysis. Phase transformation from dc-Ge to rhombohedral phase (r8-Ge was experimentally confirmed for both single and cyclic nanoindentation under high loading/unloading rates. However, compared to single indentation, double cyclic indentation with a low holding load between the cycles caused more frequent phase transformation events. Double cyclic indentation caused more stress in Ge than single indentation and increased the possibility of phase transformation. With increase in the holding load, the number of phase transformation events decreased and finally became less than that under single indentation. This phenomenon was possibly caused by defect nucleation and shear accumulation during the holding process, which were promoted by a high holding load. The defect nucleation suppressed the phase transformation from dc-Ge to r8-Ge, and shear accumulation led to another phase transformation pathway, respectively. A high holding load promoted these two phenomena, and thus decreased the possibility of phase transformation from dc-Ge to r8-Ge.

  18. Investigation and modeling of the anomalous yield point phenomenon in pure tantalum

    Energy Technology Data Exchange (ETDEWEB)

    Colas, D. [Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 5209 CNRS, Université de Bourgogne, 9 avenue Alain Savary, BP 17870, 21078 Dijon Cedex (France); CEA Valduc, 21120 Is-sur-Tille (France); Mines ParisTech, Centre des Matériaux, CNRS, UMR 7633, BP 87, 91003 Evry Cedex (France); Finot, E. [Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 5209 CNRS, Université de Bourgogne, 9 avenue Alain Savary, BP 17870, 21078 Dijon Cedex (France); Flouriot, S. [CEA Valduc, 21120 Is-sur-Tille (France); Forest, S. [Mines ParisTech, Centre des Matériaux, CNRS, UMR 7633, BP 87, 91003 Evry Cedex (France); Mazière, M., E-mail: matthieu.maziere@mines-paristech.fr [Mines ParisTech, Centre des Matériaux, CNRS, UMR 7633, BP 87, 91003 Evry Cedex (France); Paris, T. [CEA Valduc, 21120 Is-sur-Tille (France)

    2014-10-06

    The monotonic and cyclic behavior of commercially pure tantalum has been investigated at room temperature, in order to capture and understand the occurrence of the anomalous yield point phenomenon. Interrupted tests have been performed, with strain reversals (tensile or compressive loading) after an aging period. The stress drop is attributed to the interactions between dislocations and solute atoms (oxygen) and its macroscopic occurrence is not systematically observed. InfraRed Thermography (IRT) measurements supported by Scanning Electron Microscopy (SEM) pictures of the polished gauge length of a specimen during an interrupted tensile test reveal the nucleation and propagation of a strain localization band. The KEMC (Kubin–Estrin–McCormick) phenomenological model accounting for strain aging has been identified for several loadings and strain rates at room temperature. Simulations on full specimen using the KEMC model do not show strain localization, because of the competition between viscosity and strain localization. However, a slight misalignment of the sample can promote strain localization.

  19. Cyclic transformation of orbital angular momentum modes

    International Nuclear Information System (INIS)

    Schlederer, Florian; Krenn, Mario; Fickler, Robert; Malik, Mehul; Zeilinger, Anton

    2016-01-01

    The spatial modes of photons are one realization of a QuDit, a quantum system that is described in a D-dimensional Hilbert space. In order to perform quantum information tasks with QuDits, a general class of D-dimensional unitary transformations is needed. Among these, cyclic transformations are an important special case required in many high-dimensional quantum communication protocols. In this paper, we experimentally demonstrate a cyclic transformation in the high-dimensional space of photonic orbital angular momentum (OAM). Using simple linear optical components, we show a successful four-fold cyclic transformation of OAM modes. Interestingly, our experimental setup was found by a computer algorithm. In addition to the four-cyclic transformation, the algorithm also found extensions to higher-dimensional cycles in a hybrid space of OAM and polarization. Besides being useful for quantum cryptography with QuDits, cyclic transformations are key for the experimental production of high-dimensional maximally entangled Bell-states. (paper)

  20. From an equilibrium based MOF adsorbent to a kinetic selective carbon molecular sieve for paraffin/iso-paraffin separation

    KAUST Repository

    Li, Baiyan

    2016-11-04

    We unveil a unique kinetic driven separation material for selectively removing linear paraffins from iso-paraffins via a molecular sieving mechanism. Subsequent carbonization and thermal treatment of CD-MOF-2, the cyclodextrin metal-organic framework, afforded a carbon molecular sieve with a uniform and reduced pore size of ca. 5.0 Å, and it exhibited highly selective kinetic separation of n-butane and n-pentane from iso-butane and iso-pentane, respectively. © The Royal Society of Chemistry.

  1. Cryogenic adsorption of low-concentration hydrogen on charcoal, 5A molecular sieve, sodalite, ZSM-5 and Wessalith DAY

    International Nuclear Information System (INIS)

    Willms, R.S.

    1993-01-01

    The separation of low-concentration hydrogen isotopes from helium is a processing step that is required for ceramic lithium breeding blanket processing. Cryogenic adsorption is one method of effecting this separation. In this study live adsorbents were considered for this purpose: charcoal, 5A molecular sieve, UOP S-115, ZSM-5 and Wessalith DAY. The first two adsorbents exhibit good equilibrium loadings and are shown to be quite effective at adsorbing low-concentration hydrogen isotopes. The latter three adsorbents display considerably lower equilibrium loadings. This study concludes that by using either charcoal or 5A molecular sieve, cryogenic adsorption would be an effective means of separating hydrogen isotopes from helium

  2. On the equivalence of cyclic and quasi-cyclic codes over finite fields

    Directory of Open Access Journals (Sweden)

    Kenza Guenda

    2017-07-01

    Full Text Available This paper studies the equivalence problem for cyclic codes of length $p^r$ and quasi-cyclic codes of length $p^rl$. In particular, we generalize the results of Huffman, Job, and Pless (J. Combin. Theory. A, 62, 183--215, 1993, who considered the special case $p^2$. This is achieved by explicitly giving the permutations by which two cyclic codes of prime power length are equivalent. This allows us to obtain an algorithm which solves the problem of equivalency for cyclic codes of length $p^r$ in polynomial time. Further, we characterize the set by which two quasi-cyclic codes of length $p^rl$ can be equivalent, and prove that the affine group is one of its subsets.

  3. Deformation Behavior of Recycled Concrete Aggregate during Cyclic and Dynamic Loading Laboratory Tests

    Directory of Open Access Journals (Sweden)

    Wojciech Sas

    2016-09-01

    Full Text Available Recycled concrete aggregate (RCA is a relatively new construction material, whose applications can replace natural aggregates. To do so, extensive studies on its mechanical behavior and deformation characteristics are still necessary. RCA is currently used as a subbase material in the construction of roads, which are subject to high settlements due to traffic loading. The deformation characteristics of RCA must, therefore, be established to find the possible fatigue and damage behavior for this new material. In this article, a series of triaxial cyclic loading and resonant column tests is used to characterize fatigue in RCA as a function of applied deviator stress after long-term cyclic loading. A description of the shakedown phenomenon occurring in the RCA and calculations of its resilient modulus (Mr as a function of fatigue are also presented. Test result analysis with the stress-life method on the Wohler S-N diagram shows the RCA behavior in accordance with the Basquin law.

  4. Powerful Radio Burst Indicates New Astronomical Phenomenon

    Science.gov (United States)

    2007-09-01

    Astronomers studying archival data from an Australian radio telescope have discovered a powerful, short-lived burst of radio waves that they say indicates an entirely new type of astronomical phenomenon. Region of Strong Radio Burst Visible-light (negative greyscale) and radio (contours) image of Small Magellanic Cloud and area where burst originated. CREDIT: Lorimer et al., NRAO/AUI/NSF Click on image for high-resolution file ( 114 KB) "This burst appears to have originated from the distant Universe and may have been produced by an exotic event such as the collision of two neutron stars or the death throes of an evaporating black hole," said Duncan Lorimer, Assistant Professor of Physics at West Virginia University (WVU) and the National Radio Astronomy Observatory (NRAO). The research team led by Lorimer consists of Matthew Bailes of Swinburne University in Australia, Maura McLaughlin of WVU and NRAO, David Narkevic of WVU, and Fronefield Crawford of Franklin and Marshall College in Lancaster, Pennsylvania. The astronomers announced their findings in the September 27 issue of the online journal Science Express. The startling discovery came as WVU undergraduate student David Narkevic re-analyzed data from observations of the Small Magellanic Cloud made by the 210-foot Parkes radio telescope in Australia. The data came from a survey of the Magellanic Clouds that included 480 hours of observations. "This survey had sought to discover new pulsars, and the data already had been searched for the type of pulsating signals they produce," Lorimer said. "We re-examined the data, looking for bursts that, unlike the usual ones from pulsars, are not periodic," he added. The survey had covered the Magellanic Clouds, a pair of small galaxies in orbit around our own Milky Way Galaxy. Some 200,000 light-years from Earth, the Magellanic Clouds are prominent features in the Southern sky. Ironically, the new discovery is not part of these galaxies, but rather is much more distant

  5. HOST liner cyclic facilities: Facility description

    Science.gov (United States)

    Schultz, D.

    1982-01-01

    A quartz lamp box, a quartz lamp annular rig, and a low pressure liner cyclic can rig planned for liner cyclic tests are described. Special test instrumentation includes an IR-TV camera system for measuring liner cold side temperatures, thin film thermocouples for measuring liner hot side temperatures, and laser and high temperature strain gages for obtaining local strain measurements. A plate temperature of 2,000 F was obtained in an initial test of an apparatus with three quartz lamps. Lamp life, however, appeared to be limited for the standard commercial quartz lamps available. The design of vitiated and nonvitiated preheaters required for the quartz lamp annular rig and the cyclic can test rigs is underway.

  6. Cyclic cellular automata in 3D

    International Nuclear Information System (INIS)

    Reiter, Clifford A.

    2011-01-01

    Highlights: → We explore the self-organization of cyclic cellular automata in 3D. → Von Neumann, Moore and two types of intermediate neighborhoods are investigated. → Random neighborhoods self organize through phases into complex nested structures. → Demons are seen to have many alternatives in 3D. - Abstract: Cyclic cellular automata in two dimensions have long been intriguing because they self organize into spirals and that behavior can be analyzed. The form for the patterns that develop is highly dependent upon the form of the neighborhood. We extend this work to three dimensional cyclic cellular automata and observe self organization dependent upon the neighborhood type. This includes neighborhood types intermediate between Von Neumann and Moore neighborhoods. We also observe that the patterns include nested shells with the appropriate forms but that the nesting is far more complex than the spirals that occur in two dimensions.

  7. Holographic entanglement entropy and cyclic cosmology

    Science.gov (United States)

    Frampton, Paul H.

    2018-06-01

    We discuss a cyclic cosmology in which the visible universe, or introverse, is all that is accessible to an observer while the extroverse represents the total spacetime originating from the time when the dark energy began to dominate. It is argued that entanglement entropy of the introverse is the more appropriate quantity to render infinitely cyclic, rather than the entropy of the total universe. Since vanishing entanglement entropy implies disconnected spacetimes, at the turnaround when the introverse entropy is zero the disconnected extroverse can be jettisoned with impunity.

  8. Entire cyclic cohomology and modular theory

    International Nuclear Information System (INIS)

    Stoytchev, O.Ts.

    1992-04-01

    We display a close relationship between C* and W*-dynamical systems with KMS states on them and entire cyclic cohomology theory. We construct a character form which assigns to each such system (A, α, R) an even entire cyclic cocycle of the subalgebra A of differentiable (with respect to the given automorphism group) elements of A. We argue that the most interesting case is the von Neumann algebra one, where the automorphism group is determined uniquely by the faithful normal state on the algebra (the modular group) and where the character may provide important information about the algebra. (author). 11 refs

  9. Shape of zooplankton and retention in filter-feeding: A quantitative comparison between industril sieves and the branchial sieves of common bream (Abramis brama) and white bream (Blicca bjoerkna)

    NARCIS (Netherlands)

    Van den Berg, C.M.G.; Van den Boogaart, J.G.M.; Sibbing, F.A.; Lammens, E.H.R.R.; Osse, J.W.M.

    1993-01-01

    Industrial sieves retained all cycloid copepods with a width larger than their mesh size, but Daphnia, with a width up to 1.4 times the mesh size, still passed through them. Daphnia have a lower depth/width ratio than copepods (0.599 and 0.882, respectively). Therefore, Daphnia could pass through

  10. Phenomenon of fatigue in epitaxial films of lead zirconate-titanate; Yavlenie ustalosti v ehpitaksial`nykh plenkakh tsirkonata-titanata svintsa

    Energy Technology Data Exchange (ETDEWEB)

    Shur, V Ya; Ponomarev, N Yu; Tonkacheva, N A [NII Fiziki i Prikladnoj Matematiki pri Ural` skom GosUniversitete, Ekaterinburg (Russian Federation); and others

    1997-04-01

    It is ascertained, that fatigue phenomenon under cyclic move in epitaxial heterostructures can be referred to incomplete move of c-domains and appearance of additional 90 gad domain walls in the domain structure, existing in a pause between pulses. fatigue kinetics is defined by the source domain structure parameters and must be essentially dependent both on conditions of luterostructure production and on the type of substrates 14 refs., 3 figs.

  11. Substructural evolution during cyclic torsion of drawn low carbon steel bars

    International Nuclear Information System (INIS)

    Correa, E.C.S.; Aguilar, M.T.P.; Monteiro, W.A.; Cetlin, P.R.

    2006-01-01

    Strain softening effects have been previously observed in drawn low carbon steel bars as a result of cyclic torsion experiments. In this paper, the substructural aspects related to the phenomenon have been investigated. Single pass drawn bars were subjected to a quarter, to a half, to a full torsion cycle and to 10 such cycles. Transmission electron microscopy revealed the development of extended microbands crossing the former dislocation arrangement of the drawn metal, which evolves to a rectangular shaped subgrains structure as torsion deformation is conducted

  12. A friction stress method for the cyclic inelastic behavior of metals

    International Nuclear Information System (INIS)

    Jhansale, H.R.

    1975-01-01

    Inelastic deformation and fatigue analyses require that computational models of inelastic material behavior be capable of simulating the various plastic stress-strain phenomena such as the memory of prior history and cycle dependent transient hardening, softening, relaxation and creep associated with cyclic loads. This paper presents such a formulation in which the transient phenomena are uniquely described in terms of a friction stress parameter and the memory phenomenon is simulated by the characteristics of a mechanical model comprising of 'Hookean Spring-Friction Slider' elements connected in series, the spring and slider within each element being connected in parallel. The formulation is ideally suited for programming on a digital computer. (Auth.)

  13. Practical-scale tests of cryogenic molecular sieve for separating low-concentration hydrogen isotopes from helium

    International Nuclear Information System (INIS)

    Willms, R.S.; Taylor, D.J.; Enoeda, Mikio; Okuno, Kenji

    1994-01-01

    Earlier bench-scale work at the Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory examined a number of adsorbents for their suitability for separating low-concentration hydrogen (no tritium) from helium. One of the effective adsorbents was Linde 5A molecular sieve. Recently, experiments including tritium were conducted using practical-scale adsorbers. These tests used existing cryogenic molecular sieve beds (CMSB's) which each contain about 1.6 kg of Linde 5A molecular sieve. They are part of the TSTA integrated tritium processing system. Gas was fed to each CMSB at about 13 SLPM with a nominal composition of 99% He, 0.98% H 2 and 0.02% HT. In all cases, for an extended period of time, the beds allowed no detectable (via Raman spectroscopy) hydrogen isotopes to escape in the bed effluent. Thereafter, the hydrogen isotopes appeared in the bed exit with a relatively sharp breakthrough curve. This work concludes that cryogenic molecular sieve adsorption is an practical and effective means of separating low-concentration hydrogen isotopes from a helium carrier

  14. Solid-phase reversible trap for [ sup 1 sup 1 C]carbon dioxide using carbon molecular sieves

    CERN Document Server

    Mock, B H; Mulholland, G T

    1995-01-01

    A simple, maintenance-free trapping technique which concentrates and purifies no-carrier-added sup 1 sup 1 CO sub 2 from gas targets is described. The trap requires no liquid nitrogen cooling and has no moving parts besides solenoid valves. It employs carbon molecular sieves to adsorb sup 1 sup 1 CO sub 2 selectively from gas targets at room temperature. Nitrogen, O sub 2 , CO, NO and moisture in the target gas which could interfere with subsequent radiochemical steps are not retained. Trapping efficiency of 1 g of sieve for sup 1 sup 1 CO sub 2 from a 240 cm sup 3 target gas dump and helium flush cycle is <99%, and the adsorbed sup 1 sup 1 CO sub 2 is recovered quantitatively as a small concentrated bolus from the carbon sieve trap by thermal desorption. This durable trap has performed reliably for more than 1 y with a single charge of carbon sieve. It has simplified the production, and improved the yields of several sup 1 sup 1 C-radiochemicals at this laboratory.

  15. Ruthenium-modified MCM-41 mesoporous molecular sieve and Y zeolite catalysts for selective hydrogenation of cinnamaldehyde

    Czech Academy of Sciences Publication Activity Database

    Hájek, J.; Kumar, N.; Mäki-Arvela, P.; Salmi, T.; Murzin, D. Z.; Paseka, Ivo; Heikkilä, T.; Laine, E.; Laukkanen, P.; Väyrynen, J.

    2003-01-01

    Roč. 251, č. 2 (2003), s. 385-396 ISSN 0926-860X R&D Projects: GA ČR GA104/03/0409 Institutional research plan: CEZ:AV0Z4032918 Keywords : mesoporous molecular sieve * zeolites * ruthenium Subject RIV: CA - Inorganic Chemistry Impact factor: 2.825, year: 2003

  16. Herbivore-induced callose deposition on the sieve plates of rice: an important mechanism for host resistance.

    Science.gov (United States)

    Hao, Peiying; Liu, Caixiang; Wang, Yuanyuan; Chen, Rongzhi; Tang, Ming; Du, Bo; Zhu, Lili; He, Guangcun

    2008-04-01

    The brown planthopper (Nilaparvata lugens Stål; BPH) is a specialist herbivore on rice (Oryza sativa) that ingests phloem sap from the plant through its stylet mouthparts. Electronic penetration graphs revealed that BPH insects spent more time wandering over plants carrying the resistance genes Bph14 and Bph15, but less time ingesting phloem than they did on susceptible plants. They also showed that their feeding was frequently interrupted. Tests with [(14)C]sucrose showed that insects ingested much less phloem sap from the resistant than the susceptible plants. BPH feeding up-regulated callose synthase genes and induced callose deposition in the sieve tubes at the point where the stylet was inserted. The compact callose remained intact in the resistant plants, but genes encoding beta-1,3-glucanases were activated, causing unplugging of the sieve tube occlusions in susceptible plants. Continuing ingestion led to a remarkable reduction in the susceptible plants' sucrose content and activation of the RAmy3D gene, leading to starch hydrolysis and ultimately carbohydrate deprivation in the plants. Our results demonstrate that BPH feeding induces the deposition of callose on sieve plates in rice and that this is an important defense mechanism that prevents insects from ingesting phloem sap. In response, however, the BPH can unplug sieve tube occlusions by activating beta-1,3-glucanase genes in rice plants.

  17. Lack of incorporation of tritiated uridine by nuclei of mature sieve elements in Metasequoia glyptostroboides and Sequoiadendron giganteum.

    Science.gov (United States)

    Hébant, C

    1975-01-01

    The majority of nuclei which persist in "mature" sieve elements of Metasequoia glyptostroboides Hu and Chen and Sequoiadendron giganteum Buchholz fail to incorporate tritiated uridine (10 μCi/ml; 7 hours incubation of stem fragments). This is interpreted as further evidence for the degenerated condition of these nuclei.

  18. Using Sieving and Unknown Sand Samples for a Sedimentation-Stratigraphy Class Project with Linkage to Introductory Courses

    Science.gov (United States)

    Videtich, Patricia E.; Neal, William J.

    2012-01-01

    Using sieving and sample "unknowns" for instructional grain-size analysis and interpretation of sands in undergraduate sedimentology courses has advantages over other techniques. Students (1) learn to calculate and use statistics; (2) visually observe differences in the grain-size fractions, thereby developing a sense of specific size…

  19. Determination of 137Cs and 210Pb using HPGe γ spectrometry as influenced by different sieve diameters

    International Nuclear Information System (INIS)

    Liu Yehan; Yu Hanqing; Geng Xiaochen; Li Yong

    2012-01-01

    Standard sieve diameter is often set as 2.00 mm to determine specific activity of 137 Cs and 210 Pb in soil samples, but it is rarely reported that whether the size of the different screening will affect the accuracy of such determination. In this study, three representative soils were employed to assess the effects of different sieve sizes on measurement of 137 Cs and 210 Pb activity in soil samples by using HPGe γ spectrometer. The targeted soil samples each were screened through the four sieve diameters 2.00, 1.00, 0.50 and 0.25 mm, respectively. It was observed that the sample of 0.25 mm took less time to reach the acceptable value of 137 Cs analysis precision and higher value of the specific activity in the three soils compared to the 2.00 mm sifting sample. As for 210 Pb measurement, the decrease of sieve diameters extended to touch the acceptable value of analysis precision but showed no significant effect on the specific activity. These results played an important role in enhancing the analysis precision of the specific activity of 137 Cs and 210 Pb in soil samples using HPGe γ Spectrometry. (authors)

  20. Comparison of layer grain size analysis with pipette and sieve analysis: a solution for the underestimation of the clay fraction

    NARCIS (Netherlands)

    Konert, M.; Vandenberghe, J.F.

    1997-01-01

    Classically, the grain size of soil and sediment samples is determined by the sieve method for the coarse fractions and by the pipette method, based on the 'Stokes' sedimentation rates, for the fine fractions. Results from the two methods are compared with results from laser diffraction size

  1. Resolving DNA at Efficiencies of More than A Million Plates per Meter Using Bare Narrow Open Capillary without Sieving Matrix

    OpenAIRE

    Zhu, Zaifang; Liu, Lei; Wang, Wei; Lu, Joann J.; Wang, Xiayan; Liu, Shaorong

    2013-01-01

    We report a novel approach for effectively separating DNA molecules in free solution. The method uses a bare narrow open capillary without any sieving matrices to resolve a wide size-range of DNA fragments at efficiencies of more than a million plates per meter routinely.

  2. New inorganic-organic hybrid materials based on SBA-15 molecular sieves involved in the quinolines synthesis

    Czech Academy of Sciences Publication Activity Database

    López-Sanz, J.; Pérez-Mayoral, E.; Soriano, E.; Sturm, M.; Martín-Aranda, R. M.; López-Peinado, A. J.; Čejka, Jiří

    2012-01-01

    Roč. 187, č. 1 (2012), s. 97-103 ISSN 0920-5861 R&D Projects: GA AV ČR KAN100400701 Institutional support: RVO:61388955 Keywords : mesoporous molecular sieves * heterogeneous catalysis * quinolines Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.980, year: 2012

  3. Moe fenomen. The Phenomenon of Fashion

    Directory of Open Access Journals (Sweden)

    Ines Piibeleht

    2012-06-01

    Full Text Available Since the last quarter of the 20th century, particularly after the “cultural turn”, the interest in fashion has been increasing in a variety of different disciplines. Fashion has begun to be investigated in many different contexts, using new theoretical approaches. Fashion can be regarded as a social phenomenon, a sign system, as art, myth, or the product of the fashion industry. The purpose of this article is not to provide a definition of fashion, but rather to raise the question of how to approach the experience of fashion analytically. The methodological issues discussed here emerged in the course of preparing for empirical research on fashion. The observations and comparisons that constitute the core of this article are the result of efforts to juxtapose different methods. The traditional history of fashion used a historical-epistemological strategy but, depending on how one defines culture, the meaning of fashion can also be analysed using methods based on different epistemological strategies. The phenomenological method elaborated by Edmund Husserl, which I have chosen for my analysis of the experience of fashion, defines culture through the experiential acts of individuals. Simply stated, phenomenology considers the world as it is given to us in our consciousness. What is most important for empirical research is that the phenomenological method makes it possible to study the structure of a concrete experience and to focus on the mechanisms of the subjective creation of meaning. Thus this article has two main foci: a theoretical analysis of how the experience of fashion can be analytically revealed using the phenomenological method, and a comparison of the phenomenological approach with methods based on other strategies. The analysis of descriptions in the first person makes it possible to highlight how experience has been constructed. People “see” fashion based on structures of meaning; when they describe their own experience

  4. Slower phloem transport in gymnosperm trees can be attributed to higher sieve element resistance

    DEFF Research Database (Denmark)

    Liesche, Johannes; Windt, Carel; Bohr, Tomas

    2015-01-01

    resulted from theoretical modeling using a simple transport resistance model. Analysis of the model parameters clearly identified sieve element (SE) anatomy as the main factor for the significantly slower carbohydrate transport speed inside the phloem in gymnosperm compared with angiosperm trees. In order......In trees, carbohydrates produced in photosynthesizing leaves are transported to roots and other sink organs over distances of up to 100 m inside a specialized transport tissue, the phloem. Angiosperm and gymnosperm trees have a fundamentally different phloem anatomy with respect to cell size, shape...... and connectivity. Whether these differences have an effect on the physiology of carbohydrate transport, however, is not clear. A meta-analysis of the experimental data on phloem transport speed in trees yielded average speeds of 56 cm h−1 for angiosperm trees and 22 cm h−1 for gymnosperm trees. Similar values...

  5. Thermal decomposition of poly(ethylene terephthalate)/mesoporous molecular sieve composites

    Institute of Scientific and Technical Information of China (English)

    RUN Mingtao; ZHANG Dayu; WU Sizhu; WU Gang

    2007-01-01

    The nonisothermal and isothermal degradation processesofpoly(ethyleneterephthalate)/mesoporous molecular sieve (PET/MMS) composites synthesized by insitu polymerization were studied by using thermogravimetric analysis in nitrogen.The nonisothermal degradation of the composite is found to be the first-order reaction.An isoconversional procedure developed by Ozawa is used to calculate the apparent activation energy (E),which is an average value of about 260 kJ/mol with the weight conversion from 0% to 30%,and is higher than that of neat PET.Isothermal degradation results are confirmed with the nonisothermal process,in which PET/MMS showed higher thermal stability than neat PET.The polymer in mesoporous channels has more stability due to the protection of the inorganic pore-wall.These results indicate that mesoporous MMS in PET/MMS composites improve the stability of the polymer.

  6. Evaluation of moisture damage in asphalt concrete with CRM motorcycle tire waste passing #50 sieve size

    Science.gov (United States)

    Siswanto, Henri; Supriyanto, Bambang; Pranoto, Pranoto; Chandra, Pria Rizky; Hakim, Arief Rahman

    2017-09-01

    The objective of this experimental research is to evaluate moisture damage in Asphalt Concrete (AC) with Crumb Rubber Modified (CRM) motorcycle tire waste passing #50 and retaining #100 sieve size. Two gradations were used in this research, the first gradation is usual for asphalt concrete base (ACB) and the second gradation is for asphalt concrete wearing course (ACWC). Marshall testing apparatus was used for testing the Marshall specimens. Seven levels of CRM content were used, namely 0%, 0.5%, 1%, 1.5%, 3%, 4.5% and 6% by weight of mixtures. Retained stability represent the level of moisture damage of AC pavement. The result indicates that addition CRM to the AC mixture increases their the stability to a maximum value and subsequent addition decrease the stability. The addition CRM to AC decreases their moisture damage susceptibility. AC with 1% CRM is the best asphalt-CRM mix.

  7. A modeling study of vacuum sorption characteristics of carbon dioxide on 4A zeolite molecular sieves

    Energy Technology Data Exchange (ETDEWEB)

    Prazniak, J.K.; Byers, C.H.

    1987-08-01

    A model is presented to describe the isothermal adsorption of carbon dioxide (CO/sub 2/) and of nitrogen (N/sub 2/) on 4A zeolite molecular sieves under cryogenic conditions. The model is comprised of a fluid-phase mass balance representing the dynamics of gas in the bed and a one-dimensional diffusion equation representing adsorption in the solid. Cubic crystals of 4A zeolite are assumed to be spherical, and the concentration dependence of the diffusivity of the sorbate in both the gas and solid phases is considered. Numerical solution of the parabolic partial differential model equations is accomplished using orthogonal collocation in conjunction with an ordinary differential equation integrator suitable for stiff equations. 34 refs., 18 figs., 5 tabs.

  8. Correlation Between Pyrolysis Atmosphere and Carbon Molecular Sieve Membrane Performance Properties

    KAUST Repository

    Kiyono, Mayumi; Koros, William J.; Williams, Paul J.

    2011-01-01

    Carbon molecular sieve (CMS) membranes have attractive separation performance properties, greatly exceeding an "upper bound" trade-off curve of polymeric membrane performance. CMS membranes are prepared by pyrolyzing polymers, well above their glass transition temperatures. Multiple factors, such as polymer precursor and pyrolysis protocol, are known to affect the separation performance. In this study, a correlation observed between pyrolysis atmosphere and CMS separation performance properties is discussed. Specifically, oxygen exposure during the pyrolysis process is the focus. The theory and details of the oxygen exposure and development of a new CMS preparation method using oxygen as a "dopant" will be described with a strong correlation observed with separation performance for CMS membranes prepared with various polymer precursors. In addition, study of possible mass transfer limitations on the oxygen "doping" process will be described to clarify the basis for the equilibrium-based interpretation of doping data. The method is also explored by changing the pyrolysis temperature. © 2011 Elsevier B.V.

  9. Manganese oxide octahedral molecular sieves as insertion electrodes for rechargeable Mg batteries

    KAUST Repository

    Rasul, Shahid; Suzuki, Shinya; Yamaguchi, Shu; Miyayama, Masaru

    2013-01-01

    Magnesium has been inserted electrochemically into manganese oxide octahedral molecular sieves (OMS-5 MnO2) at room temperature. Discharge/charge profiles show that a large amount of Mg, i.e., 0.37 Mg/Mn can be inserted electrochemically using 1 M Mg(ClO4)2/AN electrolyte when OMS-5 is prepared in presence of acetylene black. X-ray diffraction analysis and discharge/charge profiles verify that a solid state solution reaction takes place upon Mg insertion into the host lattice with concurrent reduction of Mn4+ to Mn2+. However, upon each reduction of Mn by Mg insertion and resultant dissolution into electrolyte, decrease in the active compound occurs consequently. A low intrinsic electronic conductivity of OMS-5 was suggested to play a vital role in Mg insertion into the host. © 2013 Elsevier Ltd.

  10. Synthesis, characterization, and catalytic properties of stable mesoporous molecular sieve MCM-41 prepared from zeolite mordenite

    International Nuclear Information System (INIS)

    Wang Shan; Dou Tao; Li Yuping; Zhang Ying; Li Xiaofeng; Yan Zichun

    2004-01-01

    Mesoporous molecular sieves (denoted as M-MCM-41) with ordered hexagonal structure have been successfully synthesized from the assembly of precursors from preformed zeolite Mordenite with CTAB surfactant micelle in alkaline media. The samples were characterized by XRD, N 2 adsorption, IR and DTG. The materials exhibit highly hydrothermal stability, as compared with conventional MCM-41. Characterization results indicate that the mesoporous walls of M-MCM-41 contain the secondary building units similar to those in microporous crystal of zeolite Mordenite. In catalytic dealkylation of C10 + aromatic hydrocarbon, M-MCM-41 shows higher activities in comparison with Mordenite and MCM-41, which would be ascribed to the combination of advantages of both MCM-41 (large pores) and Mordenite (strong acidity). Furthermore, this synthesis strategy could be used as a new general method for the preparation of hydrothermally stable mesoporous aluminosilicate materials under alkaline conditions

  11. Photocatalytic Properties of Nb/MCM-41 Molecular Sieves: Effect of the Synthesis Conditions

    Directory of Open Access Journals (Sweden)

    Caterine Daza Gomez

    2015-08-01

    Full Text Available The effect of synthesis conditions and niobium incorporation levels on the photocatalytic properties of Nb/MCM-41 molecular sieves was assessed. Niobium pentoxide supported on MCM-41 mesoporous silica was obtained using two methods: sol-gel and incipient impregnation, in each case also varying the percentage of niobium incorporation. The synthesized Nb-MCM-41 ceramic powders were characterized using the spectroscopic techniques of infrared spectroscopy (IR, Raman spectroscopy, X-ray diffraction (XRD, and transmission electron microscopy (TEM. The photodegradation capacity of the powders was studied using the organic molecule, methylene blue. The effect of both the method of synthesis and the percentage of niobium present in the sample on the photodegradation action of the solids was determined. The mesoporous Nb-MCM-41 that produced the greatest photodegradation response was obtained using the sol-gel method and 20% niobium incorporation.

  12. Synthesis and catalytic performance of ZSM-5/MCM-41 composite molecular sieve from palygorskite

    Science.gov (United States)

    Jiang, Jinlong; Wu, Mei; Yang, Yong; Duanmu, Chuansong; Chen, Jing; Gu, Xu

    2017-10-01

    ZSM-5/MCM-41 composite molecular sieve has been hydrothermally synthesized through a two-step crystallization process using palygorskite (PAL) as silicon and aluminum source. The products were characterized by various means and their catalytic properties for acetalization of cyclohexanone and esterification of acetic acid and n-butanol were also investigated. In the first step ZSM-5 zeolite could be formed from the acid-treated PAL after hydrothermal treatment using tetrapropylammonium bromide as template. XRD patterns, N2 adsorption and desorption data, and TEM images show that the composite obtained in the secondary step had a well-ordered mesoporous MCM-41 phase and a microporous ZSM-5 zeolite phase. Compared with ZSM-5, ZSM-5/MCM-41 composite possessed more total acid amount, weak acid sites and large pore structure due to the formation of MCM-41 and exhibited higher catalytic activity for the acetalization and esterification reaction.

  13. Manganese oxide octahedral molecular sieves as insertion electrodes for rechargeable Mg batteries

    KAUST Repository

    Rasul, Shahid

    2013-11-01

    Magnesium has been inserted electrochemically into manganese oxide octahedral molecular sieves (OMS-5 MnO2) at room temperature. Discharge/charge profiles show that a large amount of Mg, i.e., 0.37 Mg/Mn can be inserted electrochemically using 1 M Mg(ClO4)2/AN electrolyte when OMS-5 is prepared in presence of acetylene black. X-ray diffraction analysis and discharge/charge profiles verify that a solid state solution reaction takes place upon Mg insertion into the host lattice with concurrent reduction of Mn4+ to Mn2+. However, upon each reduction of Mn by Mg insertion and resultant dissolution into electrolyte, decrease in the active compound occurs consequently. A low intrinsic electronic conductivity of OMS-5 was suggested to play a vital role in Mg insertion into the host. © 2013 Elsevier Ltd.

  14. Standard guide for precision electroformed wet sieve analysis of nonplastic ceramic powders

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This guide covers the determination of the particle size distribution of pulverized alumina and quartz for particle sizes from 45 to 5 μm by wet sieving. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.2.1 The only exception is in the Section 5, Apparatus, 5.1 where there is no relevant SI equivalent. 1.3 This standard does not purport to address the safety concerns associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  15. Catalytic Reforming of Lignin-Derived Bio-Oil Over a Nanoporous Molecular Sieve Silicoaluminophosphate-11.

    Science.gov (United States)

    Park, Y K; Kang, Hyeon Koo; Jang, Hansaem; Suh, Dong Jin; Park, Sung Hoon

    2016-05-01

    Catalytic pyrolysis of lignin, a major constituent of biomass, was performed. A nanoporous molecular sieve silicoaluminophosphate-11 (SAPO-11) was selected as catalyst. Thermogravimetric analysis showed that 500 degrees C was the optimal pyrolysis temperature. Pyrolyzer-gas chromatography/mass spectroscopy was used to investigate the pyrolysis product distribution. Production of phenolics, the dominant product from the pyrolysis of lignin, was promoted by the increase in the catalyst dose. In particular, low-molecular-mass phenolics were produced more over SAPO-11, while high-molecular-mass phenolics and double-bond-containing phenolics were produced less. The fraction of aromatic compounds, including benzene, toluene, xylene, and ethylbenzene, was also increased by catalytic reforming. The catalytic effects were more pronounced when the catalyst/biomass ratio was increased. The enhanced production of aromatic compounds by an acidic catalyst obtained in this study is in good agreement with the results of previous studies.

  16. A Pilot-Scale System for Carbon Molecular Sieve Hollow Fiber Membrane Manufacturing

    KAUST Repository

    Karvan, O.

    2012-12-21

    Carbon molecular sieve (CMS) membranes offer advantages over traditional polymeric membrane materials, but scale-up of manufacturing systems has not received much attention. In the recent decade, there has been a dramatic increase in fundamental research on these materials with a variety of applications being studied. The results from a pilot-scale CMS production system are presented. This system was designed based on extensive laboratory research, and hollow fiber membranes produced in this system show similar performance compared to membranes produced using a smaller bench-scale system. After optimizing the system design, a 93% recovery of the precursor fibers for use in membrane module preparation were obtained. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Determination of molecular weight of silk fibroin by non-gel sieving capillary electrophoresis.

    Science.gov (United States)

    Wei, Wei; Zhang, Yaopeng; Shao, Huili; Hu, Xuechao

    2010-01-01

    A simple non-gel sieving capillary electrophoresis (NGSCE) method was established to determine the MW of silk fibroin using CE. The background electrolyte with a pH of 8.8 was based on three components: polyethylene glycol, tris(hydroxymethyl)aminomethane, and sodium dodecyl sulfate (SDS). NGSCE showed a good linear relationship with satisfactory reproducibility between the migration time and the MW of standard proteins. It was found that the regenerated silk fibroin had an MW around 83 kDa with a wide MW distribution (MWD). This absolute value is lower than the result obtained from SDS-polyacrylamide gel electrophoresis due to the different principles of the methods, but their similar MWD shapes indicated that NGSCE could be a feasible, highly sensitive, rapid method for determination of the MW of silk fibroin.

  18. Structure–performance characterization for carbon molecular sieve membranes using molecular scale gas probes

    KAUST Repository

    Rungta, Meha

    2015-04-01

    © 2015 Elsevier Ltd. All rights reserved. Understanding the relationship between carbon molecular sieve (CMS) pore structure and corresponding gas separation performance enables optimization for a given gas separation application. The final pyrolysis temperature and starting polymer precursor are the two critical parameters in controlling CMS performance. This study considers structure and performance changes of CMS derived from a commercially available polymer precursor at different pyrolysis temperatures. As reviewed in this paper, most traditional characterization methods based on microscopy, X-ray diffraction, spectroscopy, sorption-based pore size distribution measurements etc. provide limited information for relating separation performance to the CMS morphology and structural changes. A useful alternative approach based on different sized gases as molecular scale probes of the CMS pore structure was successfully used here in conjunction with separation data to provide critical insights into the structure-performance relationships of the engineered CMS.

  19. Cyclic Plastic Deformation and Welding Simulation

    NARCIS (Netherlands)

    Ten Horn, C.H.L.J.

    2003-01-01

    One of the concerns of a fitness for purpose analysis is the quantification of the relevant material properties. It is known from experiments that the mechanical properties of a material can change due to a monotonic plastic deformation or a cyclic plastic deformation. For a fitness for purpose

  20. Undrained Cyclic Behaviour of Dense Frederikshavn Sand

    DEFF Research Database (Denmark)

    Nielsen, Søren Kjær; Ibsen, Lars Bo; Sørensen, Kris Wessel

    2013-01-01

    A modified contour diagram is created for the Frederikshavn Sand in the undrained case for a relative density of ID = 80 %. It can be used to estimate the number of cycles to failure for a given combination of pore pressure, average and cyclic load ratio. The diagram is based on a series of undra...

  1. Driving Force Based Design of Cyclic Distillation

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Fjordbak; Huusom, Jakob Kjøbsted; Abildskov, Jens

    2017-01-01

    with mixed phase feeds. A range of binary test cases, benzene toluene, methanol water, and ethanol water, are evaluated. The advantage of the design approach in cyclic distillation is shown to be analogous to the advantages obtained in conventional continuous distillation, including a minimal utility...

  2. Cyclic Cratonic Carbonates and Phanerozoic Calcite Seas.

    Science.gov (United States)

    Wilkinson, Bruce H.

    1982-01-01

    Discusses causes of cyclicity in cratonic carbonate sequences and evidence for and potential significance of postulated primary calcite sediment components in past Paleozoic seas, outlining problems, focusing on models explaining existing data, and identifying background. Future sedimentary geologists will need to address these and related areas…

  3. Hopf Algebroids and Their Cyclic Theory

    NARCIS (Netherlands)

    Kowalzig, N.

    2009-01-01

    The main objective of this thesis is to clarify concepts of generalised symmetries in noncommutative geometry (i.e., the noncommutative analogue of groupoids and Lie algebroids) and their associated (co)homologies. These ideas are incorporated by the notion of Hopf algebroids and Hopf-cyclic

  4. Cyclic viscoelastoplasticity of polypropylene/nanoclay composites

    DEFF Research Database (Denmark)

    Drozdov, A.; Christiansen, Jesper de Claville

    2012-01-01

    Observations are reported on isotactic polypropylene/organically modified nanoclay hybrids with concentrations of filler ranging from 0 to 5 wt.% in cyclic tensile tests with a stress–controlled program (oscillations between various maximum stresses and the zero minimum stress). A pronounced effe...

  5. Breaking antidunes: Cyclic behavior due to hysteresis

    DEFF Research Database (Denmark)

    Deigaard, Rolf

    2006-01-01

    The cyclic behavior of breaking antidunes (growth, breaking of surface wave, obliteration) is investigated by use of a numerical model. The model includes the transition between supercritical and transcritical flow. As the antidune grows the flow becomes transcritical and a hydraulic jump is form...

  6. Inversion of General Cyclic Heptadiagonal Matrices

    Directory of Open Access Journals (Sweden)

    A. A. Karawia

    2013-01-01

    Full Text Available We describe a reliable symbolic computational algorithm for inverting general cyclic heptadiagonal matrices by using parallel computing along with recursion. The computational cost of it is operations. The algorithm is implementable to the Computer Algebra System (CAS such as MAPLE, MATLAB, and MATHEMATICA. Two examples are presented for the sake of illustration.

  7. Cyclic olefin copolymer-silica nanocomposites foams

    Czech Academy of Sciences Publication Activity Database

    Pegoretti, A.; Dorigato, A.; Biani, A.; Šlouf, Miroslav

    2016-01-01

    Roč. 51, č. 8 (2016), s. 3907-3916 ISSN 0022-2461 R&D Projects: GA MŠk(CZ) LO1507 Institutional support: RVO:61389013 Keywords : cyclic olefin copolymer * nanocomposites * silica Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.599, year: 2016

  8. Steady state oxygen reduction and cyclic voltammetry

    DEFF Research Database (Denmark)

    Rossmeisl, Jan; Karlberg, Gustav; Jaramillo, Thomas

    2008-01-01

    The catalytic activity of Pt and Pt3Ni for the oxygen reduction reaction is investigated by applying a Sabatier model based on density functional calculations. We investigate the role of adsorbed OH on the activity, by comparing cyclic voltammetry obtained from theory with previously published ex...

  9. Yolk-shell structured composite for fast and selective lithium ion sieving.

    Science.gov (United States)

    Li, Na; Lu, Deli; Zhang, Jinlong; Wang, Lingzhi

    2018-06-15

    Yolk-shell structured C@Li 4 Ti 5 O 12 microspheres composed of carbon core (ca. 500 nm) and sea urchin-like Li 4 Ti 5 O 12 shell (ca. 400-500 nm) are formed by hydrothermally treating the core-shell structured C@TiO 2 in the EtOH/H 2 O solution of LiOH and calcining it in N 2 atmosphere. Yolk-shell structured TiO 2 -type lithium ion sieve is further transformed from C@Li 4 Ti 5 O 12 through the acid treatment, which have a high specific surface area of 201.74 m 2 /g. The composite shows adsorption capacity towards Li + proportional to the pH value in the range of 7-13. The adsorption reaches equilibrium within 2 h with a high equilibrium adsorption capacity of 28.46 mg/g under alkaline conditions, which is ca. 8 times the value of ordinary TiO 2 lithium ion sieve with comparable size and surface area, demonstrating the enhanced adsorption is attributed to the generation of more accessible surficial voids by replacing internal part with light carbon core. The adsorption follows Freundlich and pseudo-second-order kinetic models with a high rate constant of 0.015 g/(mg·min). The selective adsorption to Li + is verified in the presence of K + , Na + , Ca 2+ and Mg 2+ . Copyright © 2018 Elsevier Inc. All rights reserved.

  10. {sup 14}CO{sub 2} processing using an improved and robust molecular sieve cartridge

    Energy Technology Data Exchange (ETDEWEB)

    Wotte, Anja, E-mail: Anja.Wotte@uni-koeln.de [Institute of Geology and Mineralogy, University of Cologne, Cologne (Germany); Wordell-Dietrich, Patrick [Thünen Institute of Climate-Smart Agriculture, Braunschweig (Germany); Wacker, Lukas [Ion Beam Physics, ETH Zurich, Zurich (Switzerland); Don, Axel [Thünen Institute of Climate-Smart Agriculture, Braunschweig (Germany); Rethemeyer, Janet [Institute of Geology and Mineralogy, University of Cologne, Cologne (Germany)

    2017-06-01

    Radiocarbon ({sup 14}C) analysis on CO{sub 2} can provide valuable information on the carbon cycle as different carbon pools differ in their {sup 14}C signature. While fresh, biogenic carbon shows atmospheric {sup 14}C concentrations, fossil carbon is {sup 14}C free. As shown in previous studies, CO{sub 2} can be collected for {sup 14}C analysis using molecular sieve cartridges (MSC). These devices have previously been made of plastic and glass, which can easily be damaged during transport. We thus constructed a robust MSC suitable for field application under tough conditions or in remote areas, which is entirely made of stainless steel. The new MSC should also be tight over several months to allow long sampling campaigns and transport times, which was proven by a one year storage test. The reliability of the {sup 14}CO{sub 2} results obtained with the MSC was evaluated by detailed tests of different procedures to clean the molecular sieve (zeolite type 13X) and for the adsorption and desorption of CO{sub 2} from the zeolite using a vacuum rig. We show that the {sup 14}CO{sub 2} results are not affected by any contamination of modern or fossil origin, cross contamination from previous samples, and by carbon isotopic fractionation. In addition, we evaluated the direct CO{sub 2} transfer from the MSC into the automatic graphitization equipment AGE with the subsequent {sup 14}C AMS analysis as graphite. This semi-automatic approach can be fully automated in the future, which would allow a high sample throughput. We obtained very promising, low blank values between 0.0018 and 0.0028 F{sup 14}C (equivalent to 50,800 and 47,200 yrs BP), which are within the analytical background and lower than results obtained in previous studies.

  11. Sieving Effect of Sorting Machine with Vibration Table Type on Cacao Pod Based Compost

    Directory of Open Access Journals (Sweden)

    Siswoyo Soekarno

    2009-10-01

    Full Text Available Cacao pod is the biggest part (70% of weight of Cacao, which was not optimaly utilized.Cacao podis one of organic material that can be functioned as an organic fertilizer, such as compost. When utilizedwith right proportion, organic fertilizer is safe for plants and not degrades the soil composition. Compostingprocess is one of utilization form of Cacao pod. The size reduction of cacao pod in the organic fertilizerprocess would help to accelerate the composting process. Smaller particle size would faster interacting withenvironment, so the composting process would be well accelerated if compared to the material with biggersize. Chopping machine of Cacao pod is used to cut the biomass to be small particle in order to be able tobe utilized as some important necessity, i.e. fertilizer or farm animals feed. However, Varies compost sizewas one of the problems faced in the composting process. Therefore, the sorting process was needed tobe done after chopping process, so the compost size became uniform and fulfill the user demand. Thisresearch was aimed at knowing the slope effect of sorting machine and rotation speed (RPM. The methodused in analyzing the results of this research was comparing the treatment factors, which are shown withhistogram. As the super small size of compost recommended for applying in the fertilizing process, so theoptimum treatment combination for having high mass fraction of SS compost grade was achieved at 12oslope of sieve table and 1400 RPM motor rotation speed. As bigger the particle densities of the compostsize as smaller the compost porosity. Mass loss was very low at all treatment combination with the valuearound 0.43-1.33%, so the sieving efficiency can be said very high.

  12. "1"4CO_2 processing using an improved and robust molecular sieve cartridge

    International Nuclear Information System (INIS)

    Wotte, Anja; Wordell-Dietrich, Patrick; Wacker, Lukas; Don, Axel; Rethemeyer, Janet

    2017-01-01

    Radiocarbon ("1"4C) analysis on CO_2 can provide valuable information on the carbon cycle as different carbon pools differ in their "1"4C signature. While fresh, biogenic carbon shows atmospheric "1"4C concentrations, fossil carbon is "1"4C free. As shown in previous studies, CO_2 can be collected for "1"4C analysis using molecular sieve cartridges (MSC). These devices have previously been made of plastic and glass, which can easily be damaged during transport. We thus constructed a robust MSC suitable for field application under tough conditions or in remote areas, which is entirely made of stainless steel. The new MSC should also be tight over several months to allow long sampling campaigns and transport times, which was proven by a one year storage test. The reliability of the "1"4CO_2 results obtained with the MSC was evaluated by detailed tests of different procedures to clean the molecular sieve (zeolite type 13X) and for the adsorption and desorption of CO_2 from the zeolite using a vacuum rig. We show that the "1"4CO_2 results are not affected by any contamination of modern or fossil origin, cross contamination from previous samples, and by carbon isotopic fractionation. In addition, we evaluated the direct CO_2 transfer from the MSC into the automatic graphitization equipment AGE with the subsequent "1"4C AMS analysis as graphite. This semi-automatic approach can be fully automated in the future, which would allow a high sample throughput. We obtained very promising, low blank values between 0.0018 and 0.0028 F"1"4C (equivalent to 50,800 and 47,200 yrs BP), which are within the analytical background and lower than results obtained in previous studies.

  13. Analysis of the pumpkin phloem proteome provides insights into angiosperm sieve tube function.

    Science.gov (United States)

    Lin, Ming-Kuem; Lee, Young-Jin; Lough, Tony J; Phinney, Brett S; Lucas, William J

    2009-02-01

    Increasing evidence suggests that proteins present in the angiosperm sieve tube system play an important role in the long distance signaling system of plants. To identify the nature of these putatively non-cell-autonomous proteins, we adopted a large scale proteomics approach to analyze pumpkin phloem exudates. Phloem proteins were fractionated by fast protein liquid chromatography using both anion and cation exchange columns and then either in-solution or in-gel digested following further separation by SDS-PAGE. A total of 345 LC-MS/MS data sets were analyzed using a combination of Mascot and X!Tandem against the NCBI non-redundant green plant database and an extensive Cucurbit maxima expressed sequence tag database. In this analysis, 1,209 different consensi were obtained of which 1,121 could be annotated from GenBank and BLAST search analyses against three plant species, Arabidopsis thaliana, rice (Oryza sativa), and poplar (Populus trichocarpa). Gene ontology (GO) enrichment analyses identified sets of phloem proteins that function in RNA binding, mRNA translation, ubiquitin-mediated proteolysis, and macromolecular and vesicle trafficking. Our findings indicate that protein synthesis and turnover, processes that were thought to be absent in enucleate sieve elements, likely occur within the angiosperm phloem translocation stream. In addition, our GO analysis identified a set of phloem proteins that are associated with the GO term "embryonic development ending in seed dormancy"; this finding raises the intriguing question as to whether the phloem may exert some level of control over seed development. The universal significance of the phloem proteome was highlighted by conservation of the phloem proteome in species as diverse as monocots (rice), eudicots (Arabidopsis and pumpkin), and trees (poplar). These results are discussed from the perspective of the role played by the phloem proteome as an integral component of the whole plant communication system.

  14. Applying wet sieving fecal particle size measurement to frugivores: A case study of the eastern chimpanzee (Pan troglodytes schweinfurthii).

    Science.gov (United States)

    Weary, Taylor E; Wrangham, Richard W; Clauss, Marcus

    2017-07-01

    Fecal particle size (FPS) as quantified by wet sieving analysis is a measure of chewing efficiency relevant for the understanding of physiological adaptations and constraints in herbivores. FPS has not been investigated systematically in frugivores, and important methodological problems remain. In particular, food items that are not chewed may skew estimates of FPS. We address such methodological issues and also assess the influence of diet type and age on FPS in wild chimpanzees. About 130 fecal samples of 38 individual chimpanzees (aged from 1.3 to ∼55 years) from the Kanyawara community of Kibale National Park (Uganda) were collected during three fruit seasons and analyzed using standardized wet sieves (pores from 16 to 0.025 mm). The effects of using different sieve series and excluding large seeds were investigated. We also assessed the relationship between FPS and sex, age, and fruit season. The treatment of seeds during the sieving process had a large influence on the results. FPS was not influenced by chimpanzee sex or age, but was smaller during a fig season (0.88 ± 0.31 mm) than during two drupe-fruit seasons (1.68 ± 0.37 mm) (0.025-4 mm sieves, excluding seeds). The absence of an age effect on FPS suggests that dental senescence might be less critical in chimpanzees, or in frugivores in general, than in folivorous herbivores. To increase the value of FPS studies for understanding frugivore and hominoid dietary evolution we propose modifications to prior herbivore protocols. © 2017 Wiley Periodicals, Inc.

  15. El Nino phenomenon, effects on the tree of coffee

    International Nuclear Information System (INIS)

    Jaramillo Robledo, Alvaro; Baldion Rincon, Jose Vicente; Guzman Martinez, Orlando

    1998-01-01

    El Nino phenomenon is manifested in the coffee by a deficiency of water in the plant, that which affects its normal development in its fruits; the author describes other alterations that affect the plants of coffee due to El Nino phenomenon

  16. Chinchirisi: The Phenomenon of "Spirit Children" Among the ...

    African Journals Online (AJOL)

    ... what others say or do, 'it is in our blood', they say. This raises concerns. In what ways and to what extent is this religio-cultural phenomenon a challenge to euthanasia, human rights and rural development in the contemporary society? This paper examines the phenomenon of 'spirit children' from an insider perspective.

  17. An Evaluation of the 'New History' Phenomenon | Moyo | Zimbabwe ...

    African Journals Online (AJOL)

    The purpose of this article was to evaluate the 'New History' approach. This paper explores the argument that the new 'New History' phenomenon was an attempt to rejuvenate an interest in History. The 'New History' phenomenon was launched because of the fear that History was in danger as it faced possible extinction ...

  18. Phenomenon of isomorphic provoking responses in cases of limited scleroderma

    Directory of Open Access Journals (Sweden)

    Talnikova Е.Е.

    2015-09-01

    Full Text Available The article presents the historical origin of the term "Koebner phenomenon". The literature data reflect the etiology, pathogenesis and epidemiology of isomorphic mechanisms provoking responses in lichen planus, psoriasis, scleroder-ma, syphilis. Variants of the Koebner phenomenon's classifications are given. The clinical cases of limited scleroderma after mechanical injury are described.

  19. Can people with Raynaud's phenomenon travel to high altitude?

    Science.gov (United States)

    Luks, Andrew M; Grissom, Colin K; Jean, Dominique; Swenson, Erik R

    2009-01-01

    To determine whether high altitude travel adversely affects mountain enthusiasts with Raynaud's phenomenon. Volunteers with Raynaud's phenomenon were recruited using announcements disseminated by organizations dedicated to climbing or wilderness travel and Internet discussion boards dedicated to mountain activities to complete an online, anonymous survey. Survey questions addressed demographic variables, aspects of their Raynaud's phenomenon, and features of their mountain activities. Respondents compared experiences with Raynaud's phenomenon between high (>2440 m; 8000 feet) and low elevations and rated agreement with statements concerning their disease and the effects of high altitude. One hundred forty-two people, 98% of whom had primary Raynaud's phenomenon, completed the questionnaire. Respondents spent 5 to 7 days per month at elevations above 2440 m and engaged in 5.4 +/- 2.0 different activities. Eighty-nine percent of respondents engaged in winter sports and only 22% reported changing their mountain activities because of Raynaud's phenomenon. Respondents reported a variety of tactics to prevent and treat Raynaud's attacks, but only 12% used prophylactic medications. Fifteen percent of respondents reported an episode of frostbite following a Raynaud's phenomenon attack at high altitude. There was considerable heterogeneity in participants' perceptions of the frequency, duration, and severity of attacks at high altitude compared to their home elevation. Motivated individuals with primary Raynaud's phenomenon, employing various prevention and treatment strategies, can engage in different activities, including winter sports, at altitudes above 2440 m. Frostbite may be common in this population at high altitude, and care must be taken to prevent its occurrence.

  20. Identification of cyclic nucleotide gated channels using regular expressions

    KAUST Repository

    Zelman, Alice K.; Dawe, Adam Sean; Berkowitz, Gerald A.

    2013-01-01

    Cyclic nucleotide-gated channels (CNGCs) are nonselective cation channels found in plants, animals, and some bacteria. They have a six-transmembrane/one- pore structure, a cytosolic cyclic nucleotide-binding domain, and a cytosolic calmodulin

  1. Effects of hypokinesia on cyclic nucleotides and hormonal regulation ...

    African Journals Online (AJOL)

    PTH), calcitonin (CT), cyclic nucleotides (cAMP, cGMP) and calcium in the blood of rats, while in urine - phosphate, calcium and cyclic nucleotides. Design: Laboratory based experiment. Setting: Laboratory in the Department of Biochemistry, ...

  2. Rhodium-Catalyzed Dehydrogenative Borylation of Cyclic Alkenes

    Science.gov (United States)

    Kondoh, Azusa; Jamison, Timothy F.

    2010-01-01

    A rhodium-catalyzed dehydrogenative borylation of cyclic alkenes is described. This reaction provides direct access to cyclic 1-alkenylboronic acid pinacol esters, useful intermediates in organic synthesis. Suzuki-Miyaura cross-coupling applications are also presented. PMID:20107646

  3. Cyclic inelastic deformation aspects of fatigue-crack-growth analysis

    Energy Technology Data Exchange (ETDEWEB)

    Leis, B.N.; Zahoor, A.

    1980-01-01

    This paper concentrates on a J-integral analysis of fatigue crack growth. Data on cyclic plasticity are analyzed showing that there are limitations to the usefulness of the deformation theory in applications to cyclic plasticity. 56 refs.

  4. Compressed sensing with cyclic-S Hadamard matrix for terahertz imaging applications

    Science.gov (United States)

    Ermeydan, Esra Şengün; ćankaya, Ilyas

    2018-01-01

    Compressed Sensing (CS) with Cyclic-S Hadamard matrix is proposed for single pixel imaging applications in this study. In single pixel imaging scheme, N = r . c samples should be taken for r×c pixel image where . denotes multiplication. CS is a popular technique claiming that the sparse signals can be reconstructed with samples under Nyquist rate. Therefore to solve the slow data acquisition problem in Terahertz (THz) single pixel imaging, CS is a good candidate. However, changing mask for each measurement is a challenging problem since there is no commercial Spatial Light Modulators (SLM) for THz band yet, therefore circular masks are suggested so that for each measurement one or two column shifting will be enough to change the mask. The CS masks are designed using cyclic-S matrices based on Hadamard transform for 9 × 7 and 15 × 17 pixel images within the framework of this study. The %50 compressed images are reconstructed using total variation based TVAL3 algorithm. Matlab simulations demonstrates that cyclic-S matrices can be used for single pixel imaging based on CS. The circular masks have the advantage to reduce the mechanical SLMs to a single sliding strip, whereas the CS helps to reduce acquisition time and energy since it allows to reconstruct the image from fewer samples.

  5. Cyclic Soft Groups and Their Applications on Groups

    Directory of Open Access Journals (Sweden)

    Hacı Aktaş

    2014-01-01

    Full Text Available In crisp environment the notions of order of group and cyclic group are well known due to many applications. In this paper, we introduce order of the soft groups, power of the soft sets, power of the soft groups, and cyclic soft group on a group. We also investigate the relationship between cyclic soft groups and classical groups.

  6. Cyclic Nucleotide Signalling in Kidney Fibrosis

    Directory of Open Access Journals (Sweden)

    Elisabeth Schinner

    2015-01-01

    Full Text Available Kidney fibrosis is an important factor for the progression of kidney diseases, e.g., diabetes mellitus induced kidney failure, glomerulosclerosis and nephritis resulting in chronic kidney disease or end-stage renal disease. Cyclic adenosine monophosphate (cAMP and cyclic guanosine monophosphate (cGMP were implicated to suppress several of the above mentioned renal diseases. In this review article, identified effects and mechanisms of cGMP and cAMP regarding renal fibrosis are summarized. These mechanisms include several signalling pathways of nitric oxide/ANP/guanylyl cyclases/cGMP-dependent protein kinase and cAMP/Epac/adenylyl cyclases/cAMP-dependent protein kinase. Furthermore, diverse possible drugs activating these pathways are discussed. From these diverse mechanisms it is expected that new pharmacological treatments will evolve for the therapy or even prevention of kidney failure.

  7. A cyclic symmetry principle in physics

    International Nuclear Information System (INIS)

    Green, H.S.; Adelaide Univ., SA

    1994-01-01

    Many areas of modern physics are illuminated by the application of a symmetry principle, requiring the invariance of the relevant laws of physics under a group of transformations. This paper examines the implications and some of the applications of the principle of cyclic symmetry, especially in the areas of statistical mechanics and quantum mechanics, including quantized field theory. This principle requires invariance under the transformations of a finite group, which may be a Sylow π-group, a group of Lie type, or a symmetric group. The utility of the principle of cyclic invariance is demonstrated in finding solutions of the Yang-Baxter equation that include and generalize known solutions. It is shown that the Sylow π-groups have other uses, in providing a basis for a type of generalized quantum statistics, and in parametrising a new generalization of Lie groups, with associated algebras that include quantized algebras. 31 refs

  8. Strain gradient effects on cyclic plasticity

    DEFF Research Database (Denmark)

    Niordson, Christian Frithiof; Legarth, Brian Nyvang

    2010-01-01

    Size effects on the cyclic shear response are studied numerically using a recent higher order strain gradient visco-plasticity theory accounting for both dissipative and energetic gradient hardening. Numerical investigations of the response under cyclic pure shear and shear of a finite slab between...... rigid platens have been carried out, using the finite element method. It is shown for elastic–perfectly plastic solids how dissipative gradient effects lead to increased yield strength, whereas energetic gradient contributions lead to increased hardening as well as a Bauschinger effect. For linearly...... hardening materials it is quantified how dissipative and energetic gradient effects promote hardening above that of conventional predictions. Usually, increased hardening is attributed to energetic gradient effects, but here it is found that also dissipative gradient effects lead to additional hardening...

  9. Generalized Toeplitz operators and cyclic vectors

    International Nuclear Information System (INIS)

    Gassier, G.; Mahzouli, H.; Zerouali, E.H.

    2003-04-01

    We give in this paper some asymptotic Von Neumann inequalities for power bounded operators in the class C ρ intersection C 1 . and some spacial von Neumann inequalities associated with non zero elements of the point spectrum, when it is non void, of generalized Toeplitz operators. Introducing perturbed kernel, we consider classes C R which extend the classical classes C ρ . We give results about absolute continuity with respect to the Haar measure for operators in class C R intersection C 1 . This allows us to give new results on cyclic vectors for such operators and provides invariant subspaces for their powers. Relationships between cyclic vectors for T and T* involving generalized Toeplitz operators are given and the commutativity of {T}', the commutant of T is discussed. (author)

  10. Cosmic evolution in a cyclic universe

    International Nuclear Information System (INIS)

    Steinhardt, Paul J.; Turok, Neil

    2002-01-01

    Based on concepts drawn from the ekpyrotic scenario and M theory, we elaborate our recent proposal of a cyclic model of the universe. In this model, the universe undergoes an endless sequence of cosmic epochs which begin with the universe expanding from a 'big bang' and end with the universe contracting to a 'big crunch'. Matching from 'big crunch' to 'big bang' is performed according to the prescription recently proposed with Khoury, Ovrut and Seiberg. The expansion part of the cycle includes a period of radiation and matter domination followed by an extended period of cosmic acceleration at low energies. The cosmic acceleration is crucial in establishing the flat and vacuous initial conditions required for ekpyrosis and for removing the entropy, black holes, and other debris produced in the preceding cycle. By restoring the universe to the same vacuum state before each big crunch, the acceleration ensures that the cycle can repeat and that the cyclic solution is an attractor

  11. Separation of isotopes by cyclical processes

    International Nuclear Information System (INIS)

    Hamrin, C.E. Jr.; Weaver, K.

    1976-01-01

    Various isotopes of hydrogen are separated by a cyclic sorption process in which a gas stream containing the isotopes is periodically passed through a high pressure column containing a palladium sorbent. A portion of the product from the high pressure column is passed through a second column at lower pressure to act as a purge. Before the sorbent in the high pressure column becomes saturated, the sequence is reversed with the stream flowing through the former low-pressure column now at high pressure, and a portion of the product purging the former high pressure column now at low pressure. The sequence is continued in cyclic manner with the product being enriched in a particular isotope

  12. Olefins-selective asymmetric carbon molecular sieve hollow fiber membranes for hybrid membrane-distillation processes for olefin/paraffin separations

    KAUST Repository

    Xu, Liren

    2012-12-01

    In this paper, the development of asymmetric carbon molecular sieve (CMS) hollow fiber membranes and advanced processes for olefin/paraffin separations based on the CMS membranes are reported. Membrane-based olefin/paraffin separations have been pursued extensively over the past decades. CMS membranes are promising to exceed the performance upper bound of polymer materials and have demonstrated excellent stability for gas separations. Previously, a substructure collapse phenomenon was found in Matrimid ® precursor derived CMS fiber. To overcome the permeance loss due to the increased separation layer thickness, 6FDA-DAM and 6FDA/BPDA-DAM precursors were selected as potential new precursors for carbon membrane formation. Defect-free asymmetric 6FDA-DAM and 6FDA/BPDA-DAM hollow fibers were successfully fabricated from a dry-jet/wet-quench spinning process. Polymer rigidity, glass-rubber transition and asymmetric morphology were correlated. CMS hollow fiber membranes produced from 6FDA-polymer precursors showed significant improvement in permeance for ethylene/ethane and propylene/propane separations. Further studies revealed that the CMS membranes are olefins-selective, which means the membranes are able to effectively separate olefins (ethylene and propylene) from paraffins (ethane and propane). This unique feature of CMS materials enables advanced hybrid membrane-distillation process designs. By using the olefins-selective membranes, these new processes may provide advantages over previously proposed retrofitting concepts. Further applications of the membranes are explored for hydrocarbons processes. Significant energy savings and even reduced footprint may be achieved in olefins production units. © 2012 Elsevier B.V.

  13. Soil Fatigue Due To Cyclically Loaded Foundations

    OpenAIRE

    Pytlik, Robert Stanislaw

    2016-01-01

    Cyclic loading on civil structures can lead to a reduction of strength of the used materials. A literature study showed that, in contrast to steel structures and material engineering, there are no design codes or standards for fatigue of foundations and the surrounding ground masses in terms of shear strength reduction. Scientific efforts to study the fatigue behaviour of geomaterials are mainly focused on strain accumulation, while the reduction of shear strength of geomaterials has not been...

  14. Reaction of cyclic epoxide compounds with triphenylphosphine

    International Nuclear Information System (INIS)

    Kas'yan, L.I.; Stepanova, N.V.; Galafeeva, M.F.; Boldeskul, I.E.; Trachevskii, V.V.; Zefirov, N.S.

    1987-01-01

    Significant differences were found in the reactivity of a series of epoxides of cycloalkenes and methylenecycloalkanes and diepoxides in reaction with triphenylphosphine, depending both on the steric effects of the cyclic fragments and on their strain. The level of the strain can be judged indirectly from the chemical shifts of the 1 H and 13 C nuclei and the spin-spin coupling constants of the C-H bonds in the epoxide ring

  15. Human skin kinetics of cyclic depsipeptide mycotoxins

    OpenAIRE

    Taevernier, Lien; Veryser, Lieselotte; ROCHE, NATHALIE; De Spiegeleer, Bart

    2014-01-01

    Cyclic depsipeptides (CDPs) are an emerging group of naturally occurring bioactive peptides, some of which are already developed as pharmaceutical drugs, e.g. valinomycin. They are produced by bacteria, marine organisms and fungi [1]. Some CDPs are secondary fungal metabolites, which can be very toxic to humans and animals, and are therefore called mycotoxins. Currently, dermal exposure data of CDP mycotoxins is scarce and fragmentary with a lack of understanding about the local skin and syst...

  16. Modelling of cyclical stratigraphy using Markov chains

    Energy Technology Data Exchange (ETDEWEB)

    Kulatilake, P.H.S.W.

    1987-07-01

    State-of-the-art on modelling of cyclical stratigraphy using first-order Markov chains is reviewed. Shortcomings of the presently available procedures are identified. A procedure which eliminates all the identified shortcomings is presented. Required statistical tests to perform this modelling are given in detail. An example (the Oficina formation in eastern Venezuela) is given to illustrate the presented procedure. 12 refs., 3 tabs. 1 fig.

  17. Markup cyclicality, employment adjustment, and financial constraints

    OpenAIRE

    Askildsen, Jan Erik; Nilsen, Øivind Anti

    2001-01-01

    We investigate the existence of markups and their cyclical behaviour. Markup is not directly observed. Instead, it is given as a price-cost relation that is estimated from a dynamic model of the firm. The model incorporates potential costly employment adjustments and takes into consideration that firms may be financially constrained. When considering size of the future labour stock, financially constrained firms may behave as if they have a higher discount factor, which may affect the realise...

  18. Characterization of cyclic peptides containing disulfide bonds

    OpenAIRE

    Johnson, Mindy; Liu, Mingtao; Struble, Elaine; Hettiarachchi, Kanthi

    2015-01-01

    Unlike linear peptides, analysis of cyclic peptides containing disulfide bonds is not straightforward and demands indirect methods to achieve a rigorous proof of structure. Three peptides that belong to this category, p-Cl-Phe-DPDPE, DPDPE, and CTOP, were analyzed and the results are presented in this paper. The great potential of two dimensional NMR and ESI tandem mass spectrometry was harnessed during the course of peptide characterizations. A new RP-HPLC method for the analysis of trifluor...

  19. Visual search of cyclic spatio-temporal events

    Science.gov (United States)

    Gautier, Jacques; Davoine, Paule-Annick; Cunty, Claire

    2018-05-01

    The analysis of spatio-temporal events, and especially of relationships between their different dimensions (space-time-thematic attributes), can be done with geovisualization interfaces. But few geovisualization tools integrate the cyclic dimension of spatio-temporal event series (natural events or social events). Time Coil and Time Wave diagrams represent both the linear time and the cyclic time. By introducing a cyclic temporal scale, these diagrams may highlight the cyclic characteristics of spatio-temporal events. However, the settable cyclic temporal scales are limited to usual durations like days or months. Because of that, these diagrams cannot be used to visualize cyclic events, which reappear with an unusual period, and don't allow to make a visual search of cyclic events. Also, they don't give the possibility to identify the relationships between the cyclic behavior of the events and their spatial features, and more especially to identify localised cyclic events. The lack of possibilities to represent the cyclic time, outside of the temporal diagram of multi-view geovisualization interfaces, limits the analysis of relationships between the cyclic reappearance of events and their other dimensions. In this paper, we propose a method and a geovisualization tool, based on the extension of Time Coil and Time Wave, to provide a visual search of cyclic events, by allowing to set any possible duration to the diagram's cyclic temporal scale. We also propose a symbology approach to push the representation of the cyclic time into the map, in order to improve the analysis of relationships between space and the cyclic behavior of events.

  20. The phenomenon of domestic servants in the State of Qatar

    OpenAIRE

    Alshafai, Nedham

    2015-01-01

    Of new phenomena that emerged in the State of Qatar, and on a large scale in the post-oil era (after 1950) is domestic servant's phenomenon. Historically, the phenomenon was presented in the pre-oil and limited to the homes of the royal families, pearls' merchants, senior traders and tribal leaders. However, today the phenomenon exists in all Qatari families, under the name of maids, drivers, educators, nurses and others, recently; it began spreading in non-citizenship families as well. Base...

  1. Theoretical aspects on the phenomenon of contamination of ground waters

    International Nuclear Information System (INIS)

    Echeverri, G.E.

    1998-01-01

    The phenomenon of contamination of ground waters and the destination of certain constituents of the water keep in mind diverse mechanisms of physical nature, chemistry and biological; in this work it is consigned in a concise way, the theoretical aspects of these topics, that is to say, the basic principles of the ground water hydraulics, the fundamental concepts of the physics of the movement and the chemistry of the ground water, as well as the equations that govern the phenomenon of contamination of the mass of water contained in the interstices of the floors and the rocks, broadly used in the mathematical modeling of the phenomenon

  2. Cyclic dominance in evolutionary games: a review

    Science.gov (United States)

    Szolnoki, Attila; Mobilia, Mauro; Jiang, Luo-Luo; Szczesny, Bartosz; Rucklidge, Alastair M.; Perc, Matjaž

    2014-01-01

    Rock is wrapped by paper, paper is cut by scissors and scissors are crushed by rock. This simple game is popular among children and adults to decide on trivial disputes that have no obvious winner, but cyclic dominance is also at the heart of predator–prey interactions, the mating strategy of side-blotched lizards, the overgrowth of marine sessile organisms and competition in microbial populations. Cyclical interactions also emerge spontaneously in evolutionary games entailing volunteering, reward, punishment, and in fact are common when the competing strategies are three or more, regardless of the particularities of the game. Here, we review recent advances on the rock–paper–scissors (RPS) and related evolutionary games, focusing, in particular, on pattern formation, the impact of mobility and the spontaneous emergence of cyclic dominance. We also review mean-field and zero-dimensional RPS models and the application of the complex Ginzburg–Landau equation, and we highlight the importance and usefulness of statistical physics for the successful study of large-scale ecological systems. Directions for future research, related, for example, to dynamical effects of coevolutionary rules and invasion reversals owing to multi-point interactions, are also outlined. PMID:25232048

  3. Scale factor duality for conformal cyclic cosmologies

    Energy Technology Data Exchange (ETDEWEB)

    Silva, University Camara da; Lima, A.L. Alves; Sotkov, G.M. [Departamento de Física - CCE,Universidade Federal de Espirito Santo, 29075-900, Vitoria ES (Brazil)

    2016-11-16

    The scale factor duality is a symmetry of dilaton gravity which is known to lead to pre-big-bang cosmologies. A conformal time version of the scale factor duality (SFD) was recently implemented as a UV/IR symmetry between decelerated and accelerated phases of the post-big-bang evolution within Einstein gravity coupled to a scalar field. The problem investigated in the present paper concerns the employment of the conformal time SFD methods to the construction of pre-big-bang and cyclic extensions of these models. We demonstrate that each big-bang model gives rise to two qualitatively different pre-big-bang evolutions: a contraction/expansion SFD model and Penrose’s Conformal Cyclic Cosmology (CCC). A few examples of SFD symmetric cyclic universes involving certain gauged Kähler sigma models minimally coupled to Einstein gravity are studied. We also describe the specific SFD features of the thermodynamics and the conditions for validity of the generalized second law in the case of Gauss-Bonnet (GB) extension of these selected CCC models.

  4. Scale factor duality for conformal cyclic cosmologies

    International Nuclear Information System (INIS)

    Silva, University Camara da; Lima, A.L. Alves; Sotkov, G.M.

    2016-01-01

    The scale factor duality is a symmetry of dilaton gravity which is known to lead to pre-big-bang cosmologies. A conformal time version of the scale factor duality (SFD) was recently implemented as a UV/IR symmetry between decelerated and accelerated phases of the post-big-bang evolution within Einstein gravity coupled to a scalar field. The problem investigated in the present paper concerns the employment of the conformal time SFD methods to the construction of pre-big-bang and cyclic extensions of these models. We demonstrate that each big-bang model gives rise to two qualitatively different pre-big-bang evolutions: a contraction/expansion SFD model and Penrose’s Conformal Cyclic Cosmology (CCC). A few examples of SFD symmetric cyclic universes involving certain gauged Kähler sigma models minimally coupled to Einstein gravity are studied. We also describe the specific SFD features of the thermodynamics and the conditions for validity of the generalized second law in the case of Gauss-Bonnet (GB) extension of these selected CCC models.

  5. Textural mesoporosity and the catalytic activity of mesoporous molecular sieves with wormhole framework structures

    International Nuclear Information System (INIS)

    Pauly, T.R.; Liu, Y.; Pinnavaia, T.J.; Billinge, S.J.L.; Rieker, T.P.

    1999-01-01

    Three different water-alcohol cosolvent systems were used to assemble mesoporous molecular sieve silicas with wormhole framework structures (previously denoted HMS silicas) from an electrically neutral amine surfactant (Sdegree) and a silicon alkoxide precursor (Idegree). The fundamental particle size and associated textural (interparticle) porosity of the disordered structures were correlated with the solubility of the surfactant in the water-alcohol cosolvents used for the SdegreeIdegree assembly process. Polar cosolvents containing relatively low volume fractions of C n H 2n+1 OH alcohols (n = 1--3) gave heterogeneous surfactant emulsions that assembled intergrown aggregates of small primary particles with high textural pore volumes (designated HMS-HTx). Conversely, three-dimensional, monolithic particles with little or no textural porosity (designated HMS-LTx) were formed from homogeneous surfactant solutions in lower polarity cosolvents. Aluminum substituted AL-HMS-HTx analogues with high textural porosity and improved framework accessibility also were shown to be much more efficient catalysts than AL-HMS-LTx or monolithic forms of hexagonal AL-MCM-41 for the sterically demanding condensed phase alkylation of 2,4-di-tert-butylphenol with cinnamyl alcohol. Transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS) studies verified the textural differences between wormhole HMS and electrostatically assembled hexagonal MCM-41 and SBA-3 molecular sieves. Power law fits to the scattering data indicated a surface fractal (D s = 2.76) for HMS-HTx, consistent with rough surfaces. A second power law at lower-q indicated the formation of a mass fractal (D m = 1.83) consistent with branching of small fundamental particles. Hexagonal MCM-41 and SBA-3 silicas, on the other hand, exhibited scattering properties consistent with moderately rough surfaces (D s = 2.35 and 2.22, respectively) and large particle diameters (much g t1 micro m). HMS-LTx silicas

  6. APPLICATION OF THE ANOMIC THEORY ON THE PHENOMENON ...

    African Journals Online (AJOL)

    GRACE

    public service is the most potent organ for the implementation of the policies .... To what extent does the anomic theory explain the social phenomenon of ..... This tends to agree with Merton's postulation that innovation in particular is a.

  7. Various manifestations of stratification phenomenon during intravenous cholangiography

    Energy Technology Data Exchange (ETDEWEB)

    Tada, S; Nanjo, M; Kino, M; Sekiya, T; Harada, J; Kuroda, T; Anno, I [Jikei Univ., Tokyo (Japan). School of Medicine

    1979-07-01

    A classification has been made of various types of stratification phenomenon during intravenous cholangiography. The stage of gallbladder opacification in the recumbent position has been classified as (I) mottled, (II) dendritic, (III) ring-like, and (IV) homogeneous. 'Dendritic' type of stratification phenomenon has never been reported in the literature to our knowledge. At 20 min following infusion of contrast material homogeneous opacification of the gallbladder was noticed in only 14% of patients. The others fell into types I, II or III of stratification phenomenon. In contrast, 87% of the opacified gallbladders were homogeneous on the after fatty meal film. It is therefore mandatory for diagnosis that either a 24 h film or a fatty meal film be taken to avoid the stratification phenomenon.

  8. Various manifestations of stratification phenomenon during intravenous cholangiography

    International Nuclear Information System (INIS)

    Tada, S.; Nanjo, M.; Kino, M.; Sekiya, T.; Harada, J.; Kuroda, T.; Anno, I.

    1979-01-01

    A classification has been made of various types of stratification phenomenon during intravenous cholangiography. The stage of gallbladder opacification in the recumbent position has been classified as (I) mottled, (II) dendritic, (III) ring-like, and (IV) homogeneous. 'Dendritic' type of stratification phenomenon has never been reported in the literature to our knowledge. At 20 min following infusion of contrast material homogeneous opacification of the gallbladder was noticed in only 14% of patients. The others fell into types I, II or III of stratification phenomenon. In contrast, 87% of the opacified gallbladders were homogeneous on the after fatty meal film. It is therefore mandatory for diagnosis that either a 24 h film or a fatty meal film be taken to avoid the stratification phenomenon. (author)

  9. Curvature Effect and the Spectral Softening Phenomenon Detected ...

    Indian Academy of Sciences (India)

    soft spectral evolution, indicating that this spectral softening is not a rare phenomenon .... of time, there exists a temporal steep decay phase accompanied by spectral softening. (d) In most cases, the temporal power law index α and the spectral.

  10. Rock’n’Roll as a Local Musical Phenomenon

    Directory of Open Access Journals (Sweden)

    Marija Ristivojević

    2016-02-01

    Full Text Available The paper considers the process of localization of a pop cultural and musical phenomenon – rock ’n’ roll. My basic premise is that rock ’n’ roll as a global music genre can be perceived as local, and hence represents a recognizable identification element for the local population. In this case the label r ’n’ r pertain to the phenomenon of Belgrade "new wave" music, which was popular during the 1980’s. Based on the analysis of narratives from relevant documentary films, it is my intention to find out whether "new wave" was initially perceived as a local phenomenon, and what the means of constructing this image are, as well as what it is that gives this phenomenon local legitimacy and credibility.

  11. Radical Right and Radical Left Euroscepticism. A Dynamic Phenomenon

    NARCIS (Netherlands)

    Meijers, M.J.

    2017-01-01

    Euroscepticism is often regarded as a monolithic, unitary political phenomenon. After all, Eurosceptic parties, movements and voters are united in voicing their opposition to European integration. This, however, is a serious misconception: Eurosceptic politics in Western Europe is heterogeneous

  12. Negative luminescence and devices based on this phenomenon

    International Nuclear Information System (INIS)

    Ivanov-Omskii, V. I.; Matveev, B. A.

    2007-01-01

    Recent publications concerned with infrared emitters whose electrical modulation results in absorption of radiation detected as negative luminescence are reviewed. The main properties of the devices based on this phenomenon are analyzed

  13. Negative luminescence and devices based on this phenomenon

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov-Omskii, V I; Matveev, B. A. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)], E-mail: bmat@iropt3.ioffe.rssi.ru

    2007-03-15

    Recent publications concerned with infrared emitters whose electrical modulation results in absorption of radiation detected as negative luminescence are reviewed. The main properties of the devices based on this phenomenon are analyzed.

  14. Glow phenomenon surrounding the vertical stabilizer and OMS pods

    Science.gov (United States)

    1994-01-01

    This 35mm frame, photographed as the Space Shuttle Columbia was orbiting Earth during a 'night' pass, documents the glow phenomenon surrounding the vertical stabilizer and the Orbital Maneuvering System (OMS) pods of the spacecraft.

  15. A study of pulsed sieve-plate column for Th-U extraction separation process: Pt. 3

    International Nuclear Information System (INIS)

    An Yanjun; Tong Jihong; Ma Xuquan; Tai Derong

    1993-01-01

    In 50 mm diameter pulsed sieve-plate column, the mass transfer process of the Th-U low decontaminate cycle process was described by diffusion model. The model parameters of axial mixing coefficient and mass transfer coefficient were determined simultaneously and directly from concentration profile by the complex optimum method. The calculated values of concentration profile are in accordance with the experimental values. The results show that when aqueous phase is continuous in Thorex process pulsed sieve-plate column two phases axial mixing is approach, and when organic phase is continuous the axial mixing of dispersion phase is less one of continuous phase. By use of complex optimum method, many shortcomings are overcome, such as the difference between calculating and experimental results due to the selection of some unadvisable methods and easy flowing-out of computer program, etc.. This method is simple and reliable, and convergence is quicker

  16. Tourism Development and the ‘Hidden’ Phenomenon

    Directory of Open Access Journals (Sweden)

    Vincenzo ASERO

    2009-01-01

    Full Text Available This paper focus on ‘hidden’ tourism phenomenon, that is the touristdemand that in many destinations eludes the official survey system. Estimationof hidden tourism requires information drawn from tourism demand and supply,using different indicators. The critical points are: the availability and validity ofdata, the data collection time and the application of the analysis models todifferent non-homogeneous areas. Economic value of the phenomenon relies onan estimate of consumption.

  17. Oxidation of refractory sulfur compounds over Ti-containing mesoporous molecular sieves prepared by using a fluorosilicon compound.

    Science.gov (United States)

    Jeong, Kwang-Eun; Cho, Chin-Soo; Chae, Ho-Jeong; Kim, Chul-Ung; Jeong, Soon-Yong

    2010-05-01

    Titanium containing mesoporous molecular sieve (Ti-MMS) catalysts were studied for the oxidative desulfurization of refractory sulfur compounds. Ti-MMS catalysts were synthesized from fluorosilicon compounds and Ti with the hydrolysis reaction of H2SiF6 in an ammonia-surfactant mixed solution. The solid products were characterized by XRD, XRF, nitrogen adsorption, and diffuse reflectance UV-vis spectroscopy. Effects of Ti loading and oxidant/sulfur mole ratio, and sulfur species on ODS activity were investigated.

  18. Particle Size (Sieving) and Enthalpy (Acid Calorimetry) Analysis of Single-Pull K East Basin Floor and Pit Sludges

    International Nuclear Information System (INIS)

    Bredt, P.R.; Delegard, C.H.; Schmidt, A.J.; Silvers, K.L.; Thornton, B.M.; Gano, S.

    2000-01-01

    This report presents the results of particle size analyses and calorimetry testing performed on selected single-pull sludge samples collected from the Hanford K East Basin between December 1998 and June 1999. The samples were collected as isolated cores predominantly from areas that had not been previously sampled (e.g., North Loadout Pit, Dummy Elevator Pit, Tech View Pit), or from areas in which the sludge composition had been altered since the last sampling (e.g., Weasel Pit). Particle size analyses were performed by washing wet sludge samples through a series of four sieves with openings of 250, 500, 1410, and 4000 microm. The loaded sieves were weighed before and after drying to obtain wet and dry particle size distributions. Knowledge of the particle size distribution is needed to design and predict the performance of the systems that will be used to retrieve, transport, and recover sludge. Also, sieving provides an opportunity to observe the components in the sludge. For example, during sieving of the sludge sample from the North Loadout Pit, significant quantities of organic ion exchange beads were observed. The uranium metal content and the particle size of the uranium metal in the K Basin sludge will largely determine the chemical reactivity of the sludge. In turn, the designs for the sludge handling and storage systems must be compatible with the reactivity of the sludge. Therefore, acid calorimetry was performed to estimate the uranium metal content of the sludge. For this testing, sludge samples were dissolved in nitric acid within a calibrated adiabatic calorimeter. The resulting dissolution enthalpy data were then used to discriminate between metallic uranium (minus3750 J/g in nitric acid) and uranium oxide (minus394 J/g in nitric acid). Results from this testing showed that the single-pull sludge samples contained little or no uranium metal

  19. The Diagnostic Value of the Vacuum Phenomenon during Hip Arthroscopy

    Science.gov (United States)

    Rath, Ehud; Gortzak, Yair; Schwarzkopf, Ran; Benkovich, Vadim; Cohen, Eugene; Atar, Dan

    2011-01-01

    The diagnostic value of the vacuum phenomenon between the femoral head and the acetabulum, and time frame of its occurrence after application of traction is an important clinical question. The resulting arthrogram may outline the shape, location, and extent of cartilage lesions prior to arthroscopy of the hip joint. The presence, duration, and diagnostic information of the vacuum phenomenon were evaluated in 24 hips that underwent arthroscopy. The operative diagnosis was compared to the results of imaging studies and to findings obtained during a traction trial prior to arthroscopy. Indications for arthroscopy included avascular necrosis, labral tears, loose bodies, osteoarthrosis, and intractable hip pain. In 22 hips the vacuum phenomenon developed within 30 seconds after application of traction. The most important data obtained from the vacuum phenomenon was the location and extent of femoral head articular cartilage detachment and the presence of nonossified loose bodies. The vacuum phenomenon did not reveal labral or acetabular cartilage pathology in any of these patients. The vacuum phenomenon obtained during the trial of traction can add valuable information prior to hip arthroscopy. Femoral head articular cartilage detachment was best documented by this method. The hip arthroscopist should utilize this diagnostic window routinely prior to hip arthroscopy. PMID:24977068

  20. VALUE OF THE PHENOMENON OF DEJA VU IN HEALTHY EXAMINEES

    Directory of Open Access Journals (Sweden)

    Pavel Nikolaevich Vlasov

    2009-01-01

    Full Text Available The purpose of the investigation was to study the clinical value of the deja vu phenomenon in healthy examinees as it may occur in healthy individuals, on the one hand, and is a symptom of a number of psychoneurological diseases, on the other. One hundred and twenty-nine subjects, mean age 25,2±4,4 years, were examined. All the examinees were questioned by the original questionnaire developed by the authors, which was to reveal the characteristics of the phenomenon, and the Cambridge depersonalization questionnaire; standard electroencephalography was also performed. The deja vu phenomenon was detected in 97% of the respondents. In healthy individuals, the phenomenon was most common at the age of 21-25 years; 52,2% experienced deja vu several times a year; 64,5% of the respondents reported the 10-sec state; 85% did not associate the occurrence of the phenomenon with any provoking factor; 66% perceived deja vu with a positive emotional tinge, and only 4% of the respondents were afraid of the onset of this phenomenon. These criteria may be used to rule out pathological deja vu

  1. Statistical damage constitutive model for rocks subjected to cyclic stress and cyclic temperature

    Science.gov (United States)

    Zhou, Shu-Wei; Xia, Cai-Chu; Zhao, Hai-Bin; Mei, Song-Hua; Zhou, Yu

    2017-10-01

    A constitutive model of rocks subjected to cyclic stress-temperature was proposed. Based on statistical damage theory, the damage constitutive model with Weibull distribution was extended. Influence of model parameters on the stress-strain curve for rock reloading after stress-temperature cycling was then discussed. The proposed model was initially validated by rock tests for cyclic stress-temperature and only cyclic stress. Finally, the total damage evolution induced by stress-temperature cycling and reloading after cycling was explored and discussed. The proposed constitutive model is reasonable and applicable, describing well the stress-strain relationship during stress-temperature cycles and providing a good fit to the test results. Elastic modulus in the reference state and the damage induced by cycling affect the shape of reloading stress-strain curve. Total damage induced by cycling and reloading after cycling exhibits three stages: initial slow increase, mid-term accelerated increase, and final slow increase.

  2. Covalent Anchoring of Chloroperoxidase and Glucose Oxidase on the Mesoporous Molecular Sieve SBA-15

    Directory of Open Access Journals (Sweden)

    Martin Hartmann

    2010-02-01

    Full Text Available Functionalization of porous solids plays an important role in many areas, including heterogeneous catalysis and enzyme immobilization. In this study, large-pore ordered mesoporous SBA-15 molecular sieves were synthesized with tetraethyl orthosilicate (TEOS in the presence of the non-ionic triblock co-polymer Pluronic P123 under acidic conditions. These materials were grafted with 3 aminopropyltrimethoxysilane (ATS, 3-glycidoxypropyltrimethoxysilane (GTS and with 3 aminopropyltrimethoxysilane and glutaraldehyde (GA-ATS in order to provide covalent anchoring points for enzymes. The samples were characterized by nitrogen adsorption, powder X-ray diffraction, solid-state NMR spectroscopy, elemental analysis, diffuse reflectance fourier transform infrared spectroscopy and diffuse reflectance UV/Vis spectroscopy. The obtained grafted materials were then used for the immobilization of chloroperoxidase (CPO and glucose oxidase (GOx and the resulting biocatalysts were tested in the oxidation of indole. It is found that enzymes anchored to the mesoporous host by the organic moieties can be stored for weeks without losing their activity. Furthermore, the covalently linked enzymes are shown to be less prone to leaching than the physically adsorbed enzymes, as tested in a fixed-bed reactor under continuous operation conditions.

  3. Sorbate Transport in Carbon Molecular Sieve Membranes and FAU/EMT Intergrowth by Diffusion NMR

    Directory of Open Access Journals (Sweden)

    John J. Low

    2012-02-01

    Full Text Available In this paper we present and discuss selected results of our recent studies of sorbate self-diffusion in microporous materials. The main focus is given to transport properties of carbon molecular sieve (CMS membranes as well as of the intergrowth of FAU-type and EMT-type zeolites. CMS membranes show promise for applications in separations of mixtures of small gas molecules, while FAU/EMT intergrowth can be used as an active and selective cracking catalyst. For both types of applications diffusion of guest molecules in the micropore networks of these materials is expected to play an important role. Diffusion studies were performed by a pulsed field gradient (PFG NMR technique that combines advantages of high field (17.6 T NMR and high magnetic field gradients (up to 30 T/m. This technique has been recently introduced at the University of Florida in collaboration with the National Magnet Lab. In addition to a more conventional proton PFG NMR, also carbon-13 PFG NMR was used.

  4. Production of carbon molecular sieves from palm shell through carbon deposition from methane

    Directory of Open Access Journals (Sweden)

    Mohammadi Maedeh

    2011-01-01

    Full Text Available The possibility of production of carbon molecular sieve (CMS from palm shell as a waste lignocellulosic biomass was investigated. CMS samples were prepared through heat treatment processes including carbonization, physiochemical activation and chemical vapor deposition (CVD from methane. Methane was pyrolyzed to deposit fine carbon on the pore mouth of palm shell-based activated carbon to yield CMS. All the deposition experiments were performed at 800 ºC, while the methane flow rate (100, 200, 300 mL min-1 CH4 diluted in 500 mL min-1 N2 and deposition time (30 to 60 min were the investigated parameters. The textural characteristics of the CMSs were assessed by N2 adsorption. The largest BET surface area (752 m2 g-1, micropore surface area (902.2 m2 g-1 and micropore volume (0.3466 cm3 g-1 was obtained at the CH4 flow rate of 200 mL min-1 and deposition time of 30 min. However, prolonging the deposition time to 45 min yielded in a micropouros CMS with a narrow pore size distribution.

  5. Speciation of copper diffused in a bi-porous molecular sieve

    International Nuclear Information System (INIS)

    Huang, C.-H.; Paul Wang, H.; Wei, Y.-L.; Chang, J.-E.

    2010-01-01

    To better understand diffusion of copper in the micro- and mesopores, speciation of copper in a bi-porous molecular sieve (BPMS) possessing inter-connecting 3-D micropores (0.50-0.55 nm) and 2-D mesopores (4.1 nm) has been studied by X-ray absorption near edge structure (XANES) spectroscopy. It is found that about 77% (16% of CuO nanoparticles and 61% of CuO clusters) and 23% (CuO ads ) of copper can be diffused into the meso- and micropores, respectively, in the BPMS. At least two diffusion steps in the BPMS may be involved: (i) free diffusion of copper in the mesopores and (ii) diffusion-controlled copper migrating into the micropores of the BPMS. The XANES data also indicate that diffusion rate of copper in the BPMS (4.68x10 -5 g/s) is greater than that in the ZSM-5 (1.11x10 -6 g/s) or MCM-41 (1.17x10 -5 g/s).

  6. Mixed Matrix Carbon Molecular Sieve and Alumina (CMS-Al2O3) Membranes.

    Science.gov (United States)

    Song, Yingjun; Wang, David K; Birkett, Greg; Martens, Wayde; Duke, Mikel C; Smart, Simon; Diniz da Costa, João C

    2016-07-29

    This work shows mixed matrix inorganic membranes prepared by the vacuum-assisted impregnation method, where phenolic resin precursors filled the pore of α-alumina substrates. Upon carbonisation, the phenolic resin decomposed into several fragments derived from the backbone of the resin matrix. The final stages of decomposition (>650 °C) led to a formation of carbon molecular sieve (CMS) structures, reaching the lowest average pore sizes of ~5 Å at carbonisation temperatures of 700 °C. The combination of vacuum-assisted impregnation and carbonisation led to the formation of mixed matrix of CMS and α-alumina particles (CMS-Al2O3) in a single membrane. These membranes were tested for pervaporative desalination and gave very high water fluxes of up to 25 kg m(-2) h(-1) for seawater (NaCl 3.5 wt%) at 75 °C. Salt rejection was also very high varying between 93-99% depending on temperature and feed salt concentration. Interestingly, the water fluxes remained almost constant and were not affected as feed salt concentration increased from 0.3, 1 and 3.5 wt%.

  7. Mathematical model and simulation of the hydrodynamic of air-pulsed sieve plate columns

    International Nuclear Information System (INIS)

    Hannappel, J.; Pfeifer, W.; Rathjen, E.

    1979-02-01

    In this work the dynamic flow events in an air pulsed sieve plate column are described by a simulation model. The model consists of a system of differential equations. The pressure built up by the pulsed air is brought to equilibrium with the pressure losses of the oscillating liquid column in the pulsation tube and in the column. In case of definition of the a) column geometry, b) integral holdup of the column, c) density of the participating phases, d) control times of the pulsed air valves, e) pulse repetition frequency and pulsed air reservoir pressure the height of oscillation and hence the intensity of pulsation are calculated. It is shown by a concrete example that 1) the oscillation of the liquid column in the pulsation tube and in the column is sinusoidal in all cases; 2) generation of a defined pulsation is restricted to the range between 0.3 and 3 Hz; 3) the amount of air needed for pulsation depends on the geometry of the column and in the intensity of pulsation. It can be optimized by appropriate selection of the diameter of the pulsation tube. (orig.) [de

  8. Dynamic adsorption property of xenon on activated carbon and carbon molecular sieves

    International Nuclear Information System (INIS)

    Feng Shujuan; Zhou Guoqing; Jin Yuren; Zhou Chongyang

    2010-01-01

    In order to select well adsorptive xenon adsorbent, the dynamic adsorption property of xenon on activated carbon and carbon molecular sieves (CMS) was studied by measuring the xenon dynamic adsorption coefficient as a function velocity of gas, temperature, carrier gas, pressure and concentration of CO 2 . The results show that the highest value of xenon dynamic adsorption coefficient is on CMS1, and the second highest value is on CMS2; when the xenon concentration is less than 10 -5 mol/L or concentration of CO 2 is less than 5 x 10 -5 mol/L, the xenon dynamic adsorption coefficient nearly keeps constant at the specific experimental flow rate. Then the xenon dynamic adsorption coefficient would vary when it was mixed with different kind of carrier gas and become less at more than 5 x 10 -5 mol/L concentration of CO 2 . And the maximal effect factors are temperature and pressure. Therefore, the feasible measures to improve the xenon capability are to cool the adsorbent and increase adsorption pressure. (authors)

  9. [Removal of toluene from waste gas by honeycomb adsorption rotor with modified 13X molecular sieves].

    Science.gov (United States)

    Wang, Jia-De; Zheng, Liang-Wei; Zhu, Run-Ye; Yu, Yun-Feng

    2013-12-01

    The removal of toluene from waste gas by Honeycomb Adsorption Rotor with modified 13X molecular sieves was systematically investigated. The effects of the rotor operating parameters and the feed gas parameters on the adsorption efficiency were clarified. The experimental results indicated that the honeycomb adsorption rotor had a good humidity resistance. The removal efficiency of honeycomb adsorption rotor achieved the maximal value with optimal rotor speed and optimal generation air temperature. Moreover, for an appropriate flow rate ratio the removal efficiency and energy consumption should be taken into account. When the recommended operating parameters were regeneration air temperature of 180 degrees C, rotor speed of 2.8-5 r x h(-1), flow rate ratio of 8-12, the removal efficiency kept over 90% for the toluene gas with concentration of 100 mg x m(-3) and inlet velocity of 2 m x s(-1). The research provided design experience and operating parameters for industrial application of honeycomb adsorption rotor. It showed that lower empty bed velocity, faster rotor speed and higher temperature were necessary to purify organic waste gases of higher concentrations.

  10. Adsorbate shape selectivity: Separation of the HF/134a azeotrope over carbogenic molecular sieve

    Energy Technology Data Exchange (ETDEWEB)

    Hong, A.; Mariwala, R.K.; Kane, M.S.; Foley, H.C. [Univ. of Delaware, Nework, DE (United States)

    1995-03-01

    Experimental evidence is provided for adsorptive shape selectivity in the separation of the azeotrope between HF and 1,1,1,2-tetrafluoroethane (134a) over pyrolyzed poly(furfuryl alcohol)-derived carbogenic molecular sieve (PPFA-CMS). The separation can be accomplished over coconut charcoal or Carbosieve G on the basis of the differences in the extent of equilibrium adsorption of HF and 134a. On these adsorbents 134a is more strongly bound than HF, thus it elutes much more slowly from the bed. The heat of adsorption for 134a in the vicinity of 200 C on Carbosieve G is {approximately}8.8 kcal/mol. In contrast, when the same azeotropic mixture is separated over PPFA-CMS prepared at 500 C, 134a is not adsorbed. As a result 134a elutes from the bed first, followed by HF. The reversal is brought about by the narrower pore size and pore size distribution of the PPFA-CMS versus that for Carbosieve G. Thus the separation over PPFA-CMS is an example of adsorbate shape selectivity and represents a limiting case of kinetic separation.

  11. A study of flow performance and flooding in pulsed sieve plate extraction columns

    International Nuclear Information System (INIS)

    Zhang Quanrong; Wang Ruipian

    1986-01-01

    The pulsed sieve plate extraction columns could be divided into two types. The type II which has larger coalescence-damping coefficient K has an apparent transition region that widens when the K value has been increased. In this time, the operation condition in the column of type II is very different from that of type I. The flooding could be divided into three types: the flooding due to insufficient pulsing; emulsion flooding; and flooding due to dispersed phase and continuous phase that replace each other. The three kinds of flooding in the column of type II are very different from that in the column of type I. In the column of type II, when the value of K is about 2 to 3, emulsion flooding has occured and flooding capacity is the largest. In that column. The largest flooding capacity is usually larger than 1300 l/dm 2 · hr when the system 30% TBP(OK)-HNO 3 is used, but it cannot be used under normal conditions when the K value is larger

  12. Carbon molecular sieve gas separation membranes based on an intrinsically microporous polyimide precursor

    KAUST Repository

    Ma, Xiaohua

    2013-10-01

    We report the physical characteristics and gas transport properties for a series of pyrolyzed membranes derived from an intrinsically microporous polyimide containing spiro-centers (PIM-6FDA-OH) by step-wise heat treatment to 440, 530, 600, 630 and 800 C, respectively. At 440 C, the PIM-6FDA-OH was converted to a polybenzoxazole and exhibited a 3-fold increase in CO2 permeability (from 251 to 683 Barrer) with a 50% reduction in selectivity over CH4 (from 28 to 14). At 530 C, a distinct intermediate amorphous carbon structure with superior gas separation properties was formed. A 56% increase in CO2-probed surface area accompanied a 16-fold increase in CO2 permeability (4110 Barrer) over the pristine polymer. The graphitic carbon membrane, obtained by heat treatment at 600 C, exhibited excellent gas separation properties, including a remarkable CO2 permeability of 5040 Barrer with a high selectivity over CH4 of 38. Above 600 C, the strong emergence of ultramicroporosity (<7 Å) as evidenced by WAXD and CO2 adsorption studies elicits a prominent molecular sieving effect, yielding gas separation performance well above the permeability-selectivity trade-off curves of polymeric membranes. © 2013 Elsevier Ltd. All rights reserved.

  13. UTILIZATION OF ACTIVATED ZEOLITE AS MOLECULAR SIEVE IN CHROMATOGRAPHIC COLUMN FOR SEPARATION OF COAL TAR COMPOUNDS

    Directory of Open Access Journals (Sweden)

    Dwi Retno Nurotul Wahidiyah

    2010-06-01

    Full Text Available Application of activated zeolite (ZAA as molecular sieve to separate compounds of coal tar from vaccum fractional distillation, have been done. The size of zeolite was 10-20 mesh and used as solid phase in column chromatography with length of 30 cm. The first step of the research was coal pyrolisis and the product (tar was distillated by fractional column and vaccum system at reduced pressure 44 cmHg and maximum temperature at 200 oC. The distillate from this procedure was flowed to the column chromatography of zeolite (ZAA. The compound absorbed by zeolite was eluted with varying solvents, i.e: CCl4, acetone and ethanol. Each fraction was then analyzed by gas chromatography. The results showed, zeolite have a capability to separate the compounds of tar and it tends to absorb medium hydrocarbon. The nonpolar eluent [CCl4] gives the better result in eluting tar compound than polar (ethanol or medium polar eluents (acetone.   Keywords: zeolite, coal tar, column chromatography

  14. Synthesis, characterization, and mercury adsorption properties of hybrid mesoporous aluminosilicate sieve prepared with fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Minmin [School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China); Hou, Li-an, E-mail: 11liuminmin@tongji.edu.cn [School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China); Xi, Beidou; Zhao, Ying; Xia, Xunfeng [China Research Academy of Environmental Science, Beijing 200012 (China)

    2013-05-15

    A novel hybrid mesoporous aluminosilicate sieve (HMAS) was prepared with fly ash and impregnated with zeolite A precursors. This improved the mercury adsorption of HMAS compared to original MCM-41. The HMAS was characterized by X-ray diffraction (XRD), nitrogen adsorption–desorption, Fourier transform infrared (FTIR) analysis, transmission electron microscopy (TEM) images and {sup 29}Si and {sup 27}Al magic angle spinning nuclear magnetic resonance (MAS NMR) spectra. These showed that the HMAS structure was still retained after impregnated with zeolite A. But the surface area and pore diameter of HMAS decreased due to pore blockage. Adsorption of mercury from aqueous solution was studied on untreated MCM-41and HMAS. The mercury adsorption rate of HMAS was higher than that of origin MCM-41. The adsorption of mercury was investigated on HMAS regarding the pH of mercury solution, initial mercury concentration, and the reaction temperature. The experimental data fit well to Langmuir and Freundlich isotherm models. The Dublin–Radushkevich isotherm and the characterization show that the mercury adsorption on HMAS involved the ion-exchange mechanisms. In addition, the thermodynamic parameters suggest that the adsorption process was endothermic in nature. The adsorption of mercury on HMAS followed the first order kinetics.

  15. Synthesis and properties of large crystal of aluminum-deficient ultrasil molecular sieve materials

    International Nuclear Information System (INIS)

    Durrani, J.; Akhtar, J.; Chughtai, N.A.; Arif, M.; Saeed, K.; Ahmed, M.; Siddique, M.

    2003-01-01

    Large crystals of aluminum-deficient and silica rich molecular sieve materials such as Silicalite-I, Silicalite-II ZSM11-B and ZSM11-Fe have been synthesized hydro thermally from the aqueous silicate gel of (R/sub 2/O -SiO/sub 2/- B/sub 2/O/sub 3/ -Fe/sub 2/O/ sub 3/ -H/sub 2/O) using PTFE-lined stainless digestion bomb. The term R is a alkyl group. The synthesized materials were identified for crystallinity, thermal stability, phase, crystal structure, morphology and unit cell dimensions using thermogravimetry (TG/DTA), differential scanning calorimetric(DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and other analytical techniques. All product materials were found to be white crystalline and crysto-graphically pure. Surface area and particle size distribution of materials were also ascertained. /sup 57/Fe Mossbauer spectroscopic studies on as-synthesized and calcined samples have confirmed the uniform dispersion of Fe/sup 3+/ ions in the tetrahedral framework of ZSM11-Fe material. (author)

  16. Dimerization and endocytosis of the sucrose transporter StSUT1 in mature sieve elements.

    Science.gov (United States)

    Liesche, Johannes; Schulz, Alexander; Krügel, Undine; Grimm, Bernhard; Kühn, Christina

    2008-12-01

    The sucrose transporter StSUT1 from Solanum tuberosum was shown to be regulated post-translationally by redox reagents. Its activity is increased at least 10-fold in the presence of oxidizing agents if expressed in yeast. Oxidation has also an effect on plasma membrane targeting and dimerization of the protein. In response to oxidizing agents, StSUT1 is targeted to lipid raft-like microdomains and SUT1 protein is detectable in the detergent resistant membrane fraction of plant plasma membranes. Interestingly, StSUT1 treated with brefeldin A seems to aggregate in endocytic compartments in mature sieve elements.1 Further analysis of SUT1 targeting will certainly provide more information about the putative involvement of lipid raft-like microdomains in endocytic events. We provide here additional information on the dimerization and endocytosis of the SUT1 protein. The oligomerization of overexpressed SoSUT1 from Spinacia oleracea in transgenic potato plants was analyzed by two-dimensional gel electrophoresis and endocytosis of the StSUT1 protein was confirmed by immunogold labeling.

  17. Ultraselective Carbon Molecular Sieve Membranes with Tailored Synergistic Sorption Selective Properties.

    Science.gov (United States)

    Zhang, Chen; Koros, William J

    2017-09-01

    Membrane-based separations can reduce the energy consumption and the CO 2 footprint of large-scale fluid separations, which are traditionally practiced by energy-intensive thermally driven processes. Here, a new type of membrane structure based on nanoporous carbon is reported, which, according to this study, is best referred to as carbon/carbon mixed-matrix (CCMM) membranes. The CCMM membranes are formed by high-temperature (up to 900 °C) pyrolysis of polyimide precursor hollow-fiber membranes. Unprecedentedly high permselectivities are seen in CCMM membranes for CO 2 /CH 4 , N 2 /CH 4 , He/CH 4 , and H 2 /CH 4 separations. Analysis of permeation data suggests that the ultrahigh selectivities result from substantially increased sorption selectivities, which is hypothetically owing to the formation of ultraselective micropores that selectively exclude the bulkier CH 4 molecules. With tunable sorption selectivities, the CCMM membranes outperform flexible polymer membranes and traditional rigid molecular-sieve membranes. The capability to increase sorption selectivities is a powerful tool to leverage diffusion selectivities, and has opened the door to many challenging and economically important fluid separations that require ultrafine differentiation of closely sized molecules. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Synthesis, characterization, and mercury adsorption properties of hybrid mesoporous aluminosilicate sieve prepared with fly ash.

    Science.gov (United States)

    Liu, Minmin; Hou, Li-An; Xi, Beidou; Zhao, Ying; Xia, Xunfeng

    2013-05-15

    A novel hybrid mesoporous aluminosilicate sieve (HMAS) was prepared with fly ash and impregnated with zeolite A precursors. This improved the mercury adsorption of HMAS compared to original MCM-41. The HMAS was characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption, Fourier transform infrared (FTIR) analysis, transmission electron microscopy (TEM) images and 29 Si and 27 Al magic angle spinning nuclear magnetic resonance (MAS NMR) spectra. These showed that the HMAS structure was still retained after impregnated with zeolite A. But the surface area and pore diameter of HMAS decreased due to pore blockage. Adsorption of mercury from aqueous solution was studied on untreated MCM-41and HMAS. The mercury adsorption rate of HMAS was higher than that of origin MCM-41. The adsorption of mercury was investigated on HMAS regarding the pH of mercury solution, initial mercury concentration, and the reaction temperature. The experimental data fit well to Langmuir and Freundlich isotherm models. The Dublin-Radushkevich isotherm and the characterization show that the mercury adsorption on HMAS involved the ion-exchange mechanisms. In addition, the thermodynamic parameters suggest that the adsorption process was endothermic in nature. The adsorption of mercury on HMAS followed the first order kinetics.

  19. Molecular sieving action of the cell membrane during gradual osmotic hemolysis

    Energy Technology Data Exchange (ETDEWEB)

    MacGregor, R.D. II

    1977-05-01

    Rat erythrocytes were hemolyzed by controlled gradual osmotic hemolysis to study cell morphology and hemoglobin loss from individual cells. Results suggest that each increase in the rate of loss of a protein from the cells during the initial phases of controlled gradual osmotic hemolysis is caused by the passage of a previously impermeable species across the stressed membrane. Similarly, during the final stages of controlled gradual osmotic hemolysis, each sharp decrease in the rate of loss of a protein corresponds to the termination of a molecular flow. A theoretical model is described that predicts the molecular sieving of soluble globular proteins across the stressed red cell membrane. Hydrophobic interactions occur between the soluble proteins and the lipid bilayer portion of the cell membrane. A spectrin network subdivides the bilayer into domains that restrict the insertion of large molecules into the membrane. Other membrane proteins affect soluble protein access to the membrane. Changes in the loss curves caused by incubation of red cells are discussed in terms of the model.

  20. Capillary sieving electrophoresis and micellar electrokinetic capillary chromatography produce highly correlated separation of tryptic digests

    Science.gov (United States)

    Dickerson, Jane A.; Dovichi, Norman J.

    2011-01-01

    We perform two-dimensional capillary electrophoresis on fluorescently labeled proteins and peptides. Capillary sieving electrophoresis was performed in the first dimension and micellar electrokinetic capillary chromatography was performed in the second. A cellular homogenate was labeled with the fluorogenic reagent FQ and separated using the system. This homogenate generated a pair of ridges; the first had essentially constant migration time in the CSE dimension, while the second had essentially constant migration time in the MEKC dimension. In addition a few spots were scattered through the electropherogram. The same homogenate was digested using trypsin, and then labeled and subjected to the two dimensional separation. In this case, the two ridges observed from the original two-dimensional separation disappeared, and were replaced by a set of spots that fell along the diagonal. Those spots were identified using a local-maximum algorithm and each was fit using a two-dimensional Gaussian surface by an unsupervised nonlinear least squares regression algorithm. The migration times of the tryptic digest components were highly correlated (r = 0.862). When the slowest migrating components were eliminated from the analysis, the correlation coefficient improved to r = 0.956. PMID:20564272