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Sample records for kaolinite electronic resource

  1. Micaceous occlusions in kaolinite observed by ultramicrotomy and high resolution electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S Y [Univ. of Wisconsin, Madison; Jackson, M L; Brown, J L

    1975-01-01

    The layer structure of kaolinite from Twiggs, Georgia, and fire-clay type kaolinite (Frantex B, from France, particle size separates 2 0.2 ..mu..m was studied by high resolution electron microscopy after embedment in Spurr low-viscosity Epoxy media and thin sectioning normal to the (001) planes by an ultramicrotome. Images of the (001) planes (viewed edge-on) of both kaolinites were spaced at 7 A and generally aligned in parallel, with occasional bending into more widely spaced images of about 10 A interval. Some of the 10 A images converged to 7 A at one or both ends, forming ellipse-shaped islands 80 to 130 A thick and 300 to 500 A long. The island areas and interleaved 10 A layers between 7 A layers may represent a residue of incomplete weathering of mica to kaolinite. The proportions of micaceous occlusions were too small and the layer sequences too irregular to be detected by X-ray diffraction. The lateral continuity of the layers through the 7-10-7 A sequence in a kaolinite particle would partially interrupt or prevent expansion in dimethyl sulfoxide (DMSO) and other kaolinite intercalating media. Discrete mica particles were also observed with parallel images at 10 A, as impurities in both kaolinites. The small K content of the chemical analyses of the kaolinite samples is accounted for as interlayer K, not only in discrete mica particles but also in the micaceous occlusions.

  2. Structural Modification of Egyptian Kaolinite for Paper Coating

    International Nuclear Information System (INIS)

    Mohamed, H.F.; Hassan, M.S.; Morsy, F.A.; El-Sherbiny, S.

    2013-01-01

    The aim of this work is surface modification of Egyptian kaolinite for paper coating. Kaolinite < 2 fraction (KF) obtained using sedimentation and centrifuging techniques. Organo-kaolinite was prepared via inserting Urea (NH 2 CO NH 2 ) within the gallery of kaolinite using grinding technique for different times. Nano kaolinite was prepared from dispersion of organo-kaolinite in paper coating. The kaolinite (K), kaolinite /urea (KU) and kaolinite urea with binder (KU/Binder) were characterized using X-ray diffractometry (XRD), Infrared spectroscopy (IR) and Scanning Electron Microscopy (SEM). XRD studies revealed shifting of basal space of kaolinite from 0.714 to 1.11 nm upon grinding of kaolinite with urea for 5 h. On the other hand, the characteristic peak of kaolinite completely disappeared during dispersion of KU in paper coating suspension, which revealed the exfoliation of organo-kaolinite layers through the binder. Meanwhile, IR spectra show that NH-CO molecule exists in the intercalated kaolinite. The SEM images of KU revealed that kaolinite is intercalated U and fully exfoliation of KU achieved in KU/Binder and revealed by thin flakes with particle size ranged from 500 nm and 300 nm respectively. The modified kaolinite for paper coating increased the optical properties in terms of ISO brightness, opacity and gloss of the coated paper. There was a significant decrease in coated paper roughness compared to untreated kaolinite. Air permeance of the KF decreased in comparison with K sample, but increased sharply by intercalation of kaolinite (KU). Burst strength also started to increase with untreated kaolinite but decreased sharply with urea KU.

  3. Electronic Resource Management Systems

    Directory of Open Access Journals (Sweden)

    Mark Ellingsen

    2004-10-01

    Full Text Available Computer applications which deal with electronic resource management (ERM are quite a recent development. They have grown out of the need to manage the burgeoning number of electronic resources particularly electronic journals. Typically, in the early years of e-journal acquisition, library staff provided an easy means of accessing these journals by providing an alphabetical list on a web page. Some went as far as categorising the e-journals by subject and then grouping the journals either on a single web page or by using multiple pages. It didn't take long before it was recognised that it would be more efficient to dynamically generate the pages from a database rather than to continually edit the pages manually. Of course, once the descriptive metadata for an electronic journal was held within a database the next logical step was to provide administrative forms whereby that metadata could be manipulated. This in turn led to demands for incorporating more information and more functionality into the developing application.

  4. Characterization of exfoliated/delamination kaolinite

    International Nuclear Information System (INIS)

    Sun, Dewen; Li, Bin; Li, Yanfeng; Yu, Cui; Zhang, Bo; Fei, Huafeng

    2011-01-01

    A novel and facile approach for the preparation of exfoliated/delamination kaolinite was reported in this study. Kaolinite was mechanochemically activated by grinding with dimethylsulfoxide in a globe mill for different periods of time, and then the activated samples were treated for several hours at 120 o C to obtain the precursors of kaolinite. The resulting materials were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The experimental data indicated that the clay layers were well exfoliated/delamination under mechanochemical effect in a significantly short intercalation time. The expansion of the basal spacing (d 001 ) of raw kaolinite by 0.40 nm pointed out that the hydrogen bonds between adjacent kaolinite layers were partially broken as a result of the intercalation with dimethylsulfoxide.

  5. Co adsorption in kaolinite

    International Nuclear Information System (INIS)

    Souza, Eliel S.; Silva, Paulo S.C.

    2017-01-01

    Adsorption of metal ions in clay minerals has been used as an alternative to water and effluents treatment. Kaolinite is a clay mineral that presents low specific surface area and exchange ion capacity. Nevertheless, structural modifications can be achieved by means of acid or thermal activation. In this paper, it was studied the surface area of kaolinite/bentonite, kaolinite/activated carbon mixtures, thermal activated kaolinite and thermal activated kaolinite/activated carbon mixture. The mixture of kaolinite/activated carbon was tested for pH, contact time, interfering ions and initial concentration effects in the cobalt adsorption. Results showed that the optimized parameters are pH 6 and contact time of 30 min. Chromium acted as a competitive ion, zinc does not appear to have affected adsorption while iron seems to have favored it. Langmuir and Freundlich isotherms indicated that the adsorption of Co in the mixture of kaolinite/activated carbon is a spontaneous process. (author)

  6. Co adsorption in kaolinite

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Eliel S.; Silva, Paulo S.C., E-mail: eliel201019@hotmail.com, E-mail: pscsilva@ipen.br [Instituto de Pesquisas Energética s e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    Adsorption of metal ions in clay minerals has been used as an alternative to water and effluents treatment. Kaolinite is a clay mineral that presents low specific surface area and exchange ion capacity. Nevertheless, structural modifications can be achieved by means of acid or thermal activation. In this paper, it was studied the surface area of kaolinite/bentonite, kaolinite/activated carbon mixtures, thermal activated kaolinite and thermal activated kaolinite/activated carbon mixture. The mixture of kaolinite/activated carbon was tested for pH, contact time, interfering ions and initial concentration effects in the cobalt adsorption. Results showed that the optimized parameters are pH 6 and contact time of 30 min. Chromium acted as a competitive ion, zinc does not appear to have affected adsorption while iron seems to have favored it. Langmuir and Freundlich isotherms indicated that the adsorption of Co in the mixture of kaolinite/activated carbon is a spontaneous process. (author)

  7. Electronic Resource Management and Design

    Science.gov (United States)

    Abrams, Kimberly R.

    2015-01-01

    We have now reached a tipping point at which electronic resources comprise more than half of academic library budgets. Because of the increasing work associated with the ever-increasing number of e-resources, there is a trend to distribute work throughout the library even in the presence of an electronic resources department. In 2013, the author…

  8. Kaolinite Mobilisation in Sandstone

    DEFF Research Database (Denmark)

    Rosenbrand, Esther; Fabricius, Ida Lykke; Kets, Frans

    2013-01-01

    suggest that this effect is due to kaolinite clay mobilisation from the quartz grain surface; the mobilised particles subsequently plug the pore throats and reduce the permeability irreversibly. The expected hysteresis is observed when the salinity is reduced and increased; however, in contradiction...... the mobilised kaolinite particles either remain suspended and thereby increase the fluid viscosity, or form porous aggregates that can be destabilized by hydrodynamic forces. To address how the pore scale distribution of kaolinite relates to the permeability of the entire sample, we relate permeability...

  9. Metal sorption on kaolinite

    International Nuclear Information System (INIS)

    Westrich, H.R.; Brady, P.V.; Cygan, R.T.; Nagy, K.L.; Anderson, H.L.

    1997-01-01

    A key issue in performance assessment of low-level radioactive waste sites is predicting the transport and retardation of radionuclides through local soils under a variety of hydrologic and geochemical conditions. Improved transport codes should include a mechanistic model of radionuclide retardation. The authors have been investigating metal sorption (Cs + , Sr 2+ , and Ba 2+ ) on a simple clay mineral (kaolinite) to better understand the geochemical interactions of common soil minerals with contaminated groundwaters. These studies include detailed characterizations of kaolinite surfaces, experimental adsorption measurements, surface complexation modeling, and theoretical simulations of cation sorption. The aluminol edge (010) site has been identified as the most likely site for metal sorption on kaolinite in natural solutions. Relative metal binding strengths decrease from Ba 2+ to Sr 2+ to Cs + , with some portion sorbed on both kaolinite edges and basal surfaces. Some Cs + also appears to be irreversibly sorbed on both sites. Molecular dynamics simulations suggest that Cs + is sorbed at aluminol (010) edge sites as an inner-sphere complex and weakly sorbed as an outer-sphere complex on (001) basal surfaces. These results provide the basis to understand and predict metal sorption onto kaolinite, and a framework to characterize sorption processes on more complex clay minerals

  10. Theoretical study for the interlamellar aminoalcohol functionalization of kaolinite

    International Nuclear Information System (INIS)

    Hou, Xin-Juan; Li, Huiquan; Liu, Qinfu; Cheng, Hongfei; He, Peng; Li, Shaopeng

    2015-01-01

    Graphical abstract: - Highlights: • The results indicated that aminoalcohols exist with a mixing of intercalation and grafting. • Aminoalcohols can form strong hydrogen bonds with Al octahedral sheet. • The interaction between aminoalcohols and Si tetrahedral sheet are mainly attributed by vdW force. • Aminoalcohols grafting or intercalating on kaolinite have strong reactivity as electron donors. - Abstract: Fundamental problems related to aminoalcohols intercalating on kaolinite were investigated by using density functional theory method. This study examines the adsorption modes of diethanolamine and triethanolamine on kaolinite, the role of hydrogen bonds and van der Waals (vdW) forces between aminoalcohols and interlayer of kaolinite, and the change of molecular orbital occupancies of functionalized kaolinite. Results show that functionalized kaolinite is physically intercalated and covalently grafted by aminoalcohols. Non-covalent interaction analysis provides a visualized description that intercalated aminoalcohols form strong hydrogen bonds with Al octahedral sheet, and the interaction between aminoalcohols and Si tetrahedral sheet is mainly attributed to weak vdW force. The analysis of molecular orbital occupancies for kaolinite complex showed that the functionalized kaolinite has strong chemical reactivity as electron donors on the sites of grafted or intercalated aminoalcohols for further chemical reaction with other materials

  11. Bibliometric analysis on kaolinite flotation

    Directory of Open Access Journals (Sweden)

    Gabriela Lieberknecht

    Full Text Available Abstract The current work presents a bibliometric discussion on articles published worldwide concerning kaolinite flotation in international journals from 1992 to 2015. In total, 39 articles were selected from Elsevier's database, SciVerse ScienceDirect. This work allowed to recognize and identify which are the thematic and methodological trends that are being used, in addition to the main collectors used in kaolinite flotation. The results show that a significant amount of articles is produced by Chinese authors, especially from 2013, as China is the second highest aluminum producer in the world, and kaolinite is the reject in the reverse flotation process of diaspore. The results showed the difficulty of working with kaolinite flotation individually and confirmed that there is scientific collaboration among authors. Bibliometric analysis showed that the reagents used in kaolinite flotation tests are mostly derived from cationic nitrogenated compounds. Additionally, best recovery results from kaolinite flotation occurred in acidic media.

  12. Preparation of poly(vinyl alcohol)/kaolinite nanocomposites via in situ polymerization

    International Nuclear Information System (INIS)

    Jia Xin; Li Yanfeng; Zhang Bo; Cheng Qiong; Zhang Shujiang

    2008-01-01

    Poly(vinyl alcohol)/kaolinite intercalated nanocomposites (Kao-PVA) were prepared via in situ intercalation radical polymerization. Vinyl acetate (VAc) was intercalated into kaolinite by a displacement method using dimethyl sulfoxide/kaolinite (Kao-DMSO) as the intermediate. Then, PVAc/kaolinite (Kao-PVAc) was obtained via radical polymerization with benzoyl peroxide (BPO) as initiator. Last, PVAc/kaolinite was saponified via direct-hydrolysis with NaOH solution in order to obtain PVA/kaolinite nanocomposites, which was characterized by Fourier-Transformation spectroscopy (FTIR), wide X-ray diffraction (WXRD) and transmission electron microscopy (TEM). Their differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) results of the obtained PVA/kaolinite suggested that the thermal properties had an obvious improvement

  13. Interactions between kaolinite Al−OH surface and sodium hexametaphosphate

    Energy Technology Data Exchange (ETDEWEB)

    Han, Yonghua, E-mail: hyh19891102@163.com [School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083 (China); Liu, Wenli; Zhou, Jia [School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083 (China); Chen, Jianhua [College of Resources and Metallurgy, Guangxi University, Nanning 530004 (China)

    2016-11-30

    Highlights: • Sodium hexametaphosphate (NaHMP) can adsorb on kaolinite Al−OH terminated (001) surface easily. • The oxygen atoms of hexametaphosphate form strong hydrogen bonds with the hydrogen atoms of kaolinite Al−OH surface. • The electrostatic force is the main interaction between NaHMP and Al−OH surface. • The linear hexaphosphate −[PO{sub 3}]{sub m}− chains adsorb stably than −[HPO{sub 3}]{sub m}− chains. - Abstract: To investigate the dispersion mechanism of sodium hexametaphosphate on kaolinite particles, we simulated the interaction between linear polyphosphate chains and kaolinite Al−OH terminated surface by molecular dynamics, as well as the interaction between the [HPO{sub 4}]{sup 2−} anion and kaolinite Al−OH surface by density functional theory (DFT). The calculated results demonstrate that hexametaphosphate can be adsorbed by the kaolinite Al−OH surface. The oxygen atoms of hexametaphosphate anions may receive many electrons from the Al−OH surface and form hydrogen bonds with the hydrogen atoms of surface hydroxyl groups. Moreover, electrostatic force dominates the interactions between hexametaphosphate anions and kaolinite Al−OH surface. Therefore, after the adsorption of hexametaphosphate on kaolinite Al−OH surface, the kaolinite particles carry more negative charge and the electrostatic repulsion between particles increases. In addition, the adsorption of −[PO{sub 3}]{sub m}− species on the Al−OH surface should be more stable than the adsorption of −[HPO{sub 3}]{sub m}− species.

  14. Managing electronic resources a LITA guide

    CERN Document Server

    Weir, Ryan O

    2012-01-01

    Informative, useful, current, Managing Electronic Resources: A LITA Guide shows how to successfully manage time, resources, and relationships with vendors and staff to ensure personal, professional, and institutional success.

  15. Intercalation and Exfoliation of Kaolinite with Sodium Dodecyl Sulfate

    Directory of Open Access Journals (Sweden)

    Xiaochao Zuo

    2018-03-01

    Full Text Available Kaolinite (Kaol was intercalated with dimethyl sulfoxide (DMSO and subsequently methanol (MeOH to prepare intercalation compounds Kaol-DMSO and Kaol-MeOH. Kaol-MeOH was used as an intermediate to synthesize Kaol-sodium dodecyl sulfate (SDS intercalation compound (Kaol-SDS via displacement reaction. The ultrasonic exfoliation of Kaol-SDS produced a resultant Kaol-SDS-U. The samples were characterized by X-ray diffraction (XRD, Fourier transformation infrared spectroscopy (FTIR, thermal analysis, scanning electronic microscopy (SEM, transmission electron microscopy (TEM and particle size analysis. The results revealed that the intercalation of sodium dodecyl sulfate into kaolinite layers caused an obvious increase of the basal spacing from 0.72–4.21 nm. The dehydroxylation temperature of Kaol-SDS was obviously lower than that of original kaolinite. During the intercalation process of sodium dodecyl sulfate, a few kaolinite layers were exfoliated and curled up from the edges of the kaolinite sheets. After sonication treatment, the kaolinite layers were further transformed into nanoscrolls, and the exfoliated resultant Kaol-SDS-U possessed a smaller particle size close to nanoscale.

  16. Bibliometric analysis on kaolinite flotation

    OpenAIRE

    Lieberknecht, Gabriela; Matai, Patrícia Helena Lara dos Santos; Leal Filho, Laurindo de Salles

    2017-01-01

    Abstract The current work presents a bibliometric discussion on articles published worldwide concerning kaolinite flotation in international journals from 1992 to 2015. In total, 39 articles were selected from Elsevier's database, SciVerse ScienceDirect. This work allowed to recognize and identify which are the thematic and methodological trends that are being used, in addition to the main collectors used in kaolinite flotation. The results show that a significant amount of articles is produc...

  17. Electronic Resources Management Project Presentation 2012

    KAUST Repository

    Ramli, Rindra M.

    2012-11-05

    This presentation describes the electronic resources management project undertaken by the KAUST library. The objectives of this project is to migrate information from MS Sharepoint to Millennium ERM module. One of the advantages of this migration is to consolidate all electronic resources into a single and centralized location. This would allow for better information sharing among library staff.

  18. Implementing CORAL: An Electronic Resource Management System

    Science.gov (United States)

    Whitfield, Sharon

    2011-01-01

    A 2010 electronic resource management survey conducted by Maria Collins of North Carolina State University and Jill E. Grogg of University of Alabama Libraries found that the top six electronic resources management priorities included workflow management, communications management, license management, statistics management, administrative…

  19. Growth mechanisms, polytypism, and real structure of kaolinite microcrystals

    International Nuclear Information System (INIS)

    Samotoin, N. D.

    2008-01-01

    The mechanisms of growth of kaolinite microcrystals (0.1-5.0 μm in size) at deposits related to the cluvial weathering crust, as well as to the low-temperature and medium-temperature hydrothermal processes of transformations of minerals in different rocks in Russia, Kazakhstan, Ukraine, Czechia, Vietnam, India, Cuba, and Madagascar, are investigated using transmission electron microscopy and vacuum decoration with gold. It is established that kaolinite microcrystals grow according to two mechanisms: the mechanism of periodic formation of two-dimensional nuclei and the mechanism of spiral growth. The spiral growth of kaolinite microcrystals is dominant and occurs on steps of screw dislocations that differ in sign and magnitude of the Burgers vector along the c axis. The layered growth of kaolinite originates from a widespread source in the form of a step between polar (+ and -) dislocations, i.e., a growth analogue of the Frank-Read dislocation source. The density of growth screw dislocations varies over a wide range and can be as high as ∼10 9 cm -2 . Layered stepped kaolinite growth pyramids for all mechanisms of growth on the (001) face of kaolinite exhibit the main features of the triclinic 1Tc and real structures of this mineral.

  20. Electronic Resources Management System: Recommendation Report 2017

    KAUST Repository

    Ramli, Rindra M.

    2017-01-01

    This recommendation report provides an overview of the selection process for the new Electronic Resources Management System. The library has decided to move away from Innovative Interfaces Millennium ERM module. The library reviewed 3 system

  1. Electronic Resources Management Project Presentation 2012

    KAUST Repository

    Ramli, Rindra M.

    2012-01-01

    This presentation describes the electronic resources management project undertaken by the KAUST library. The objectives of this project is to migrate information from MS Sharepoint to Millennium ERM module. One of the advantages of this migration

  2. PRINCIPLES OF CONTENT FORMATION EDUCATIONAL ELECTRONIC RESOURCE

    Directory of Open Access Journals (Sweden)

    О Ю Заславская

    2017-12-01

    Full Text Available The article considers modern possibilities of information and communication technologies for the design of electronic educational resources. The conceptual basis of the open educational multimedia system is based on the modular architecture of the electronic educational resource. The content of the electronic training module can be implemented in several versions of the modules: obtaining information, practical exercises, control. The regularities in the teaching process in modern pedagogical theory are considered: general and specific, and the principles for the formation of the content of instruction at different levels are defined, based on the formulated regularities. On the basis of the analysis, the principles of the formation of the electronic educational resource are determined, taking into account the general and didactic patterns of teaching.As principles of the formation of educational material for obtaining information for the electronic educational resource, the article considers: the principle of methodological orientation, the principle of general scientific orientation, the principle of systemic nature, the principle of fundamentalization, the principle of accounting intersubject communications, the principle of minimization. The principles of the formation of the electronic training module of practical studies in the article include: the principle of systematic and dose based consistency, the principle of rational use of study time, the principle of accessibility. The principles of the formation of the module for monitoring the electronic educational resource can be: the principle of the operationalization of goals, the principle of unified identification diagnosis.

  3. Electronic Resources Management System: Recommendation Report 2017

    KAUST Repository

    Ramli, Rindra M.

    2017-05-01

    This recommendation report provides an overview of the selection process for the new Electronic Resources Management System. The library has decided to move away from Innovative Interfaces Millennium ERM module. The library reviewed 3 system as potential replacements namely: Proquest 360 Resource Manager, Ex Libris Alma and Open Source CORAL ERMS. After comparing and trialling the systems, it was decided to go for Proquest 360 Resource Manager.

  4. CHALLENGES OF ELECTRONIC INFORMATION RESOURCES IN ...

    African Journals Online (AJOL)

    This paper discusses the role of policy for proper and efficient library services in the electronic era. It points out some of the possible dangers of embarking in electronic resources without a proper focus at hand. Thus, it calls for today's librarians and policy makers to brainstorm and come up with working policies suitable to ...

  5. Characterisation of kaolinite and adsorption of europium on kaolinite

    International Nuclear Information System (INIS)

    Olin, M.; Puhakka, E.; Lehikoinen, J.; Puukko, E.; Hakanen, M.; Lindberg, A.

    2007-10-01

    Kaolinite is a common fracture mineral in many crystalline rocks and, thus, a potential sorbent for groundwater solutes. The low cation-exchange capacity makes kaolinite a good mineral to study sorption by inner-sphere complexation of multivalent ions, such as trivalent actinides or their analogues, the trivalent lanthanides. The sorption of europium and americium on kaolinite has been studied previously by Puukko and Hakanen using a natural kaolinite, KGa-1b (from the Clay Minerals Society, USA). This work describes the determination of surface-charging mechanism and surface acidity constants for KGa-1b kaolinite, and adsorption of Eu(III) on both the natural (KGa-1b) and its acid-conditioned form (HKGa). The ionic strength of the background NaNO 3 electrolyte used in these titrations was 0.05 M, 0.1 M and 0.5 M. The surface acidity of kaolinite was explained using the FITEQL software by applying the 1-pK model. The optimized concentration of surface sites was close to a value previously reported for KGa-1b kaolinite. The adsorption modelling of europium was carried out by adopting one surfacecomplexation and one cation-exchange reaction. In the acidic pH range, sorption of europium decreased with increasing ionic strength of the NaNO 3 solution, which is an indication of the dominance of cation exchange or outer-sphere complexation. At the lowest ionic strength, the sorption was reversible. In the 0.1 M and 0.5 M NaNO 3 solutions, the sorption of europium in the basic pH range was only partly reversible, or desorption kinetically slow. The degree of irreversibility increased with increasing pH and ionic strength. A diffuse-layer model was readily fitted on the per-cents sorbed scale (default in FITEQL), but the results were not as good on a Kd scale, especially at circumneutral pH values. In the water analysis of the batch titration of KGa-1b kaolinite, the main observed elements were aluminium and zinc. The concentrations of Al and Zn decreased with p

  6. Kaolinite flocculation induced by smectite addition - a transmission X-ray microscopic study.

    Science.gov (United States)

    Zbik, Marek S; Song, Yen-Fang; Frost, Ray L

    2010-09-01

    The influence of smectite addition on kaolinite suspensions in water was investigated by transmission X-ray microscopy (TXM) and Scanning Electron Microscopy (SEM). Sedimentation test screening was also conducted. Micrographs were processed by the STatistic IMage Analysing (STIMAN) program and structural parameters were calculated. From the results of the sedimentation tests important influences of small smectite additions to about 3wt.% on kaolinite suspension flocculation has been found. In order to determine the reason for this smectite impact on kaolinite suspension, macroscopic behaviour micro-structural examination using Transmission X-ray Microscope (TXM) and SEM has been undertaken. TXM & SEM micrographs of freeze-dried kaolinite-smectite suspensions with up to 20% smectite showed a high degree of orientation of the fabric made of highly oriented particles and greatest density when 3wt.% of smectite was added to the 10wt.% dense kaolinite suspension. In contrast, suspensions containing pure kaolinite do not show such platelet mutual orientation but homogenous network of randomly oriented kaolinite platelets. This suggests that in kaolinite-smectite suspensions, smectite forms highly oriented basic framework into which kaolinite platelets may bond in face to face preferential contacts strengthening structure and allowing them to show plastic behaviour which is cause of platelets orientation. Copyright 2010 Elsevier Inc. All rights reserved.

  7. Fracture in Kaolinite clay suspensions

    Science.gov (United States)

    Kosgodagan Acharige, Sebastien; Jerolmack, Douglas J.; Arratia, Paulo E.

    2017-11-01

    Clay minerals are involved in many natural (landslides, river channels) and industrial processes (ceramics, cosmetics, oil recovery). They are plate shaped charged colloids and exhibit different flow properties than simpler colloids when suspended in a liquid such as thixotropy and shear-banding. kaolinite platelets are non-swelling, meaning that the stacks formed by the platelets do not have water layers, and thus the suspension does not have a sol-gel transition. However, it has been shown that kaolinite suspensions possesses a non-zero yield stress even at low concentrations, indicating that the particles arrange themselves in a structure through attractive interactions. Here, we experimentally investigate the sedimentation of kaolinite suspensions in a Hele-Shaw cell. The sedimentation of these dilute suspensions can display solid behavior like fracture, revealed in cross-polarized light, which is linked to the failure of the weakly-bonded structure (typical yield stress 10-2 Pa). By changing the interaction potential of the particles (by sonication or introducing salts), we show through these sedimentation experiments, how the fracture pattern can be avoided. Research was sponsored by the Army Research Laboratory and was accomplished under Grant Number 569074.

  8. Library training to promote electronic resource usage

    DEFF Research Database (Denmark)

    Frandsen, Tove Faber; Tibyampansha, Dativa; Ibrahim, Glory

    2017-01-01

    Purpose: Increasing the usage of electronic resources is an issue of concern for many libraries all over the world. Several studies stress the importance of information literacy and instruction in order to increase the usage. Design/methodology/approach: The present article presents the results...

  9. Kaolinite: Defect defined material properties – A soft X-ray and first principles study of the band gap

    Energy Technology Data Exchange (ETDEWEB)

    Pietzsch, A., E-mail: annette.pietzsch@helmholtz-berlin.de [Institute for Methods and Instrumentation in Synchrotron Radiation Research G-ISRR, Helmholtz-Zentrum für Materialien und Energie GmbH, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Nisar, J. [Pakistan Atomic Energy Commission (PAEC), P.O. Box 2151, Islamabad (Pakistan); Jämstorp, E. [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Gråsjö, J. [Department of Pharmacy, Uppsala University, Box 580, 75123 Uppsala (Sweden); Århammar, C. [Coromant R& D, S-126 80 Stockholm (Sweden); Ahuja, R.; Rubensson, J.-E. [Department of Physics and Astronomy, Uppsala University, Box 516, 751 20 Uppsala (Sweden)

    2015-07-15

    Highlights: • The respective electronic structure of synthetic and natural kaolinite is compared. • The size of the band gap and thus many important material properties are defined by defect states in the band gap. • The oxygen-based defect states are identified and analyzed. • The band gap of kaolinite decreases significantly due to the forming of defects. - Abstract: By combining X-ray absorption spectroscopy and first principles calculations we have determined the electronic structure of synthetic and natural kaolinite as a model system for engineered and natural clay materials. We have analyzed defect states in the band gap and find that both natural and synthetic kaolinite contain defects where oxygen replaces hydrogen in one of the Al (0 0 1)-hydroxyl groups of the kaolinite clay sheets. The band gap of both synthetic and natural kaolinite is found to decrease by about 3.2 eV as this defect is formed.

  10. Kaolinite: Defect defined material properties – A soft X-ray and first principles study of the band gap

    International Nuclear Information System (INIS)

    Pietzsch, A.; Nisar, J.; Jämstorp, E.; Gråsjö, J.; Århammar, C.; Ahuja, R.; Rubensson, J.-E.

    2015-01-01

    Highlights: • The respective electronic structure of synthetic and natural kaolinite is compared. • The size of the band gap and thus many important material properties are defined by defect states in the band gap. • The oxygen-based defect states are identified and analyzed. • The band gap of kaolinite decreases significantly due to the forming of defects. - Abstract: By combining X-ray absorption spectroscopy and first principles calculations we have determined the electronic structure of synthetic and natural kaolinite as a model system for engineered and natural clay materials. We have analyzed defect states in the band gap and find that both natural and synthetic kaolinite contain defects where oxygen replaces hydrogen in one of the Al (0 0 1)-hydroxyl groups of the kaolinite clay sheets. The band gap of both synthetic and natural kaolinite is found to decrease by about 3.2 eV as this defect is formed

  11. Interactions between whey proteins and kaolinite surfaces

    International Nuclear Information System (INIS)

    Barral, S.; Villa-Garcia, M.A.; Rendueles, M.; Diaz, M.

    2008-01-01

    The nature of the interactions between whey proteins and kaolinite surfaces was investigated by adsorption-desorption experiments at room temperature, performed at the isoelectric point (IEP) of the proteins and at pH 7. It was found that kaolinite is a strong adsorbent for proteins, reaching the maximum adsorption capacity at the IEP of each protein. At pH 7.0, the retention capacity decreased considerably. The adsorption isotherms showed typical Langmuir characteristics. X-ray diffraction data for the protein-kaolinite complexes showed that protein molecules were not intercalated in the mineral structure, but immobilized at the external surfaces and the edges of the kaolinite. Fourier transform IR results indicate the absence of hydrogen bonding between kaolinite surfaces and the polypeptide chain. The adsorption patterns appear to be related to electrostatic interactions, although steric effects should be also considered

  12. Interactions between whey proteins and kaolinite surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Barral, S. [Department of Chemical Engineering and Environmental Technology, University of Oviedo, Julian Claveria 8, 33006 Oviedo (Spain); Villa-Garcia, M.A. [Department of Organic and Inorganic Chemistry, University of Oviedo, Julian Claveria 8, 33006 Oviedo (Spain)], E-mail: mavg@uniovi.es; Rendueles, M. [Project Management Area, University of Oviedo, Independencia 13, 33004 Oviedo (Spain); Diaz, M. [Department of Chemical Engineering and Environmental Technology, University of Oviedo, Julian Claveria 8, 33006 Oviedo (Spain)

    2008-07-15

    The nature of the interactions between whey proteins and kaolinite surfaces was investigated by adsorption-desorption experiments at room temperature, performed at the isoelectric point (IEP) of the proteins and at pH 7. It was found that kaolinite is a strong adsorbent for proteins, reaching the maximum adsorption capacity at the IEP of each protein. At pH 7.0, the retention capacity decreased considerably. The adsorption isotherms showed typical Langmuir characteristics. X-ray diffraction data for the protein-kaolinite complexes showed that protein molecules were not intercalated in the mineral structure, but immobilized at the external surfaces and the edges of the kaolinite. Fourier transform IR results indicate the absence of hydrogen bonding between kaolinite surfaces and the polypeptide chain. The adsorption patterns appear to be related to electrostatic interactions, although steric effects should be also considered.

  13. Electronic resource management systems a workflow approach

    CERN Document Server

    Anderson, Elsa K

    2014-01-01

    To get to the bottom of a successful approach to Electronic Resource Management (ERM), Anderson interviewed staff at 11 institutions about their ERM implementations. Among her conclusions, presented in this issue of Library Technology Reports, is that grasping the intricacies of your workflow-analyzing each step to reveal the gaps and problems-at the beginning is crucial to selecting and implementing an ERM. Whether the system will be used to fill a gap, aggregate critical data, or replace a tedious manual process, the best solution for your library depends on factors such as your current soft

  14. use of electronic resources by graduate students of the department

    African Journals Online (AJOL)

    respondent's access electronic resources from the internet via Cybercafé .There is a high ... KEY WORDS: Use, Electronic Resources, Graduate Students, Cybercafé. INTRODUCTION ... Faculty of Education, University of Uyo, Uyo. Olu Olat ...

  15. Formation of intercalation compound of kaolinite-glycine via displacing guest water by glycine.

    Science.gov (United States)

    Zheng, Wan; Zhou, Jing; Zhang, Zhenqian; Chen, Likun; Zhang, Zhongfei; Li, Yong; Ma, Ning; Du, Piyi

    2014-10-15

    The kaolinite-glycine intercalation compound was successfully formed by displacing intercalated guest water molecules in kaolinite hydrate as a precursor. The microstructure of the compound was characterized by X-ray diffraction, Fourier Transform Infrared Spectroscopy and Scanning Electron Microscope. Results show that glycine can only be intercalated into hydrated kaolinite to form glycine-kaolinite by utilizing water molecules as a transition phase. The intercalated glycine molecules were squeezed partially into the ditrigonal holes in the silicate layer, resulting in the interlayer distance of kaolinite reaching 1.03nm. The proper intercalation temperature range was between 20°C and 80°C. An intercalation time of 24h or above was necessary to ensure the complete formation of kaolinite-glycine. The highest intercalation degree of about 84% appeared when the system was reacted at the temperature of 80°C for 48h. There were two activation energies for the intercalation of glycine into kaolinite, one being 21kJ/mol within the temperature range of 20-65°C and the other 5.8kJ/mol between 65°C and 80°C. The intercalation degree (N) and intercalation velocity (v) of as a function of intercalation time (t) can be empirically expressed as N=-79.35e(-)(t)(/14.8)+80.1 and v=5.37e(-)(t)(/14.8), respectively. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. POLYPROPYLENE-MODIFIED KAOLINITE COMPOSITES: EFFECT ...

    African Journals Online (AJOL)

    Meziane O, Bensedira A, Guessoum M and Haddaoui N

    2016-05-01

    May 1, 2016 ... prepared by the melt intercalation method. ... several beneficial variations on stiffness, hardness, toughness and heat ..... Polypropylene/ untreated and treated kaolinite composites have been prepared via direct melt.

  17. Use of Electronic Resources in a Private University in Nigeria ...

    African Journals Online (AJOL)

    The study examined awareness and constraints in the use of electronic resources by lecturers and students of Ajayi Crowther University, Oyo, Nigeria. It aimed at justifying the resources expended in the provision of electronic resources in terms of awareness, patronage and factors that may be affecting awareness and use ...

  18. Gender Analysis Of Electronic Information Resource Use: The Case ...

    African Journals Online (AJOL)

    Based on the findings the study concluded that access and use of electronic information resources creates a “social digital divide” along gender lines. The study ... Finally, the library needs to change its marketing strategies on the availability of electronic information resources to increase awareness of these resources.

  19. Electronic Resource Management System. Vernetzung von Lizenzinformationen

    Directory of Open Access Journals (Sweden)

    Michaela Selbach

    2014-12-01

    Full Text Available In den letzten zehn Jahren spielen elektronische Ressourcen im Bereich der Erwerbung eine zunehmend wichtige Rolle: Eindeutig lässt sich hier ein Wandel in den Bibliotheken (fort vom reinen Printbestand zu immer größeren E-Only-Beständen feststellen. Die stetig wachsende Menge an E-Ressourcen und deren Heterogenität stellt Bibliotheken vor die Herausforderung, die E-Ressourcen effizient zu verwalten. Nicht nur Bibliotheken, sondern auch verhandlungsführende Institutionen von Konsortial- und Allianzlizenzen benötigen ein geeignetes Instrument zur Verwaltung von Lizenzinformationen, welches den komplexen Anforderungen moderner E-Ressourcen gerecht wird. Die Deutsche Forschungsgemeinschaft (DFG unterstützt ein Projekt des Hochschulbibliothekszentrums des Landes Nordrhein-Westfalen (hbz, der Universitätsbibliothek Freiburg, der Verbundzentrale des Gemeinsamen Bibliotheksverbundes (GBV und der Universitätsbibliothek Frankfurt, in dem ein bundesweit verfügbares Electronic Ressource Managementsystem (ERMS aufgebaut werden soll. Ein solches ERMS soll auf Basis einer zentralen Knowledge Base eine einheitliche Nutzung von Daten zur Lizenzverwaltung elektronischer Ressourcen auf lokaler, regionaler und nationaler Ebene ermöglichen. Statistische Auswertungen, Rechteverwaltung für alle angeschlossenen Bibliotheken, kooperative Datenpflege sowie ein über standardisierte Schnittstellen geführter Datenaustausch stehen bei der Erarbeitung der Anforderungen ebenso im Fokus wie die Entwicklung eines Daten- und Funktionsmodells. In the last few years the importance of electronic resources in library acquisitions has increased significantly. There has been a shift from mere print holdings to both e- and print combinations and even e-only subscriptions. This shift poses a double challenge for libraries: On the one hand they have to provide their e-resource collections to library users in an appealing way, on the other hand they have to manage these

  20. Electronic human resource management: Enhancing or entrancing?

    Directory of Open Access Journals (Sweden)

    Paul Poisat

    2017-07-01

    Full Text Available Orientation: This article provides an investigation into the current level of development of the body of knowledge related to electronic human resource management (e-HRM by means of a qualitative content analysis. Several aspects of e-HRM, namely definitions of e-HRM, the theoretical perspectives around e-HRM, the role of e-HRM, the various types of e-HRM and the requirements for successful e-HRM, are examined. Research purpose: The purpose of the article was to determine the status of e-HRM and examine the studies that report on the link between e-HRM and organisational productivity. Motivation for the study: e-HRM has the capacity to improve organisational efficiency and leverage the role of human resources (HR as a strategic business partner. Main findings: The notion that the implementation of e-HRM will lead to improved organisational productivity is commonly assumed; however, empirical evidence in this regard was found to be limited. Practical/managerial implications: From the results of this investigation it is evident that more research is required to gain a greater understanding of the influence of e-HRM on organisational productivity, as well as to develop measures for assessing this influence. Contribution: This article proposes additional areas to research and measure when investigating the effectiveness of e-HRM. It provides a different lens from which to view e-HRM assessment whilst keeping it within recognised HR measurement parameters (the HR value chain. In addition, it not only provides areas for measuring e-HRM’s influence but also provides important clues as to how the measurements may be approached.

  1. Utilization of electronic information resources by academic staff at ...

    African Journals Online (AJOL)

    The study investigated the utilization of Electronic Information resources by the academic staff of Makerere University in Uganda. It examined the academic staff awareness of the resources available, the types of resources provided by the Makerere University Library, the factors affecting resource utilization. The study was ...

  2. Users satisfaction with electronic information resources and services ...

    African Journals Online (AJOL)

    This study investigated users satisfaction on the use of electronic information resources and services in MTN Net libraries in ABU & UNIBEN. Two objectives and one null hypotheses were formulated and tested with respect to the users' satisfaction on electronic information resources and services in MTN Net libraries in ...

  3. The Role of the Acquisitions Librarian in Electronic Resources Management

    Science.gov (United States)

    Pomerantz, Sarah B.

    2010-01-01

    With the ongoing shift to electronic formats for library resources, acquisitions librarians, like the rest of the profession, must adapt to the rapidly changing landscape of electronic resources by keeping up with trends and mastering new skills related to digital publishing, technology, and licensing. The author sought to know what roles…

  4. A spectroscopic comparison of selected Chinese kaolinite, coal bearing kaolinite and halloysite--a mid-infrared and near-infrared study.

    Science.gov (United States)

    Cheng, Hongfei; Yang, Jing; Liu, Qinfu; Zhang, Jinshan; Frost, Ray L

    2010-11-01

    Mid-infrared (MIR) and near-infrared (NIR) spectroscopy have been compared and evaluated for differentiating kaolinite, coal bearing kaolinite and halloysite. Kaolinite, coal bearing kaolinite and halloysite are the three relative abundant minerals of the kaolin group, especially in China. In the MIR spectra, the differences are shown in the 3000-3600 cm⁻¹ between kaolinite and halloysite. It cannot obviously differentiate the kaolinite and halloysite, leaving alone kaolinite and coal bearing kaolinite. However, NIR, together with MIR, gives us the sufficient evidence to differentiate the kaolinite and halloysite, especially kaolinite and coal bearing kaolinite. There are obvious differences between kaolinite and halloysite in all range of their spectra, and they also show some difference between kaolinite and coal bearing kaolinite. Therefore, the reproducibility of measurement, signal to noise ratio and richness of qualitative information should be simultaneously considered for proper selection of a spectroscopic method for mineral analysis. Copyright © 2010 Elsevier B.V. All rights reserved.

  5. A spectroscopic comparison of selected Chinese kaolinite, coal bearing kaolinite and halloysite - A mid-infrared and near-infrared study

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, H.F.; Yang, J.; Liu, Q.F.; Zhang, J.S.; Frost, R.L. [Queensland University of Technology, Brisbane, Qld. (Australia). Faculty of Science & Technology

    2010-11-15

    Mid-infrared (MIR) and near-infrared (NIR) spectroscopy have been compared and evaluated for differentiating kaolinite, coal bearing kaolinite and halloysite. Kaolinite, coal bearing kaolinite and halloysite are the three relative abundant minerals of the kaolin group, especially in China. In the MIR spectra, the differences are shown in the 3000-3600 cm{sup -1} between kaolinite and halloysite. It cannot obviously differentiate the kaolinite and halloysite, leaving alone kaolinite and coal bearing kaolinite. However, NIR, together with MIR, gives us the sufficient evidence to differentiate the kaolinite and halloysite, especially kaolinite and coal bearing kaolinite. There are obvious differences between kaolinite and halloysite in all range of their spectra, and they also show some difference between kaolinite and coal bearing kaolinite. Therefore, the reproducibility of measurement, signal to noise ratio and richness of qualitative information should be simultaneously considered for proper selection of a spectroscopic method for mineral analysis.

  6. Kaolinite removal from bauxite by flotation

    Directory of Open Access Journals (Sweden)

    Otávia Martins Silva Rodrigues

    Full Text Available Abstract This paper presents a potential condition to separate kaolinite through flotation when it is present in bauxite ore. This research anticipates a Brazilian industry requirement, considering the tendency towards the need for aluminosilicates removal from bauxite ores, as has already occurred in China. Kaolinite is the most abundant aluminosilicate, and gibbsite is the main aluminum bearing mineral in Brazilian bauxite ores. The first step was a fundamental study involving microflotation experiments with pure samples of kaolinite and gibbsite. Ammonium quaternary salts and amines were used as the collector and corn starch as the depressant. In a fundamental study, the best conditions determined in the first step were evaluated for the flotation of kaolinite from bauxite ore using laboratory scale experiments. Tests with AQ142/starch (pH 10 and CTAB (pH 7 led to satisfactory results. In general, the highest values of alumina/silica mass ratio were obtained with AQ142/starch and the highest values of mass recovery and metallurgical recovery were achieved with CTAB.

  7. Selection and Evaluation of Electronic Resources

    Directory of Open Access Journals (Sweden)

    Doğan Atılgan

    2013-11-01

    Full Text Available Publication boom and issues related to controlling and accession of printed sources have created some problems after World War II. Consequently, publishing industry has encountered the problem of finding possible solution for emerged situation. Industry of electronic publishing has started to improve with the rapid increase of the price of printed sources as well as the problem of publication boom. The first effects of electronic publishing were appeared on the academic and scholarly publications then electronic publishing became a crucial part of all types of publications. As a result of these developments, collection developments and service policies of information centers were also significantly changed. In this article, after a general introduction about selection and evaluation processes of electronic publications, the subscribed databases by a state and a privately owned university in Turkey and their usage were examined.

  8. Improving Electronic Resources through Holistic Budgeting

    Science.gov (United States)

    Kusik, James P.; Vargas, Mark A.

    2009-01-01

    To establish a more direct link between its collections and the educational goals of Saint Xavier University, the Byrne Memorial Library has adopted a "holistic" approach to collection development. This article examines how traditional budget practices influenced the library's selection of resources and describes how holistic collection…

  9. Hybrid materials of kaolinite clay with polypyrrole and polyaniline.

    Science.gov (United States)

    Burridge, Kerstin A; Johnston, James H; Borrmann, Thomas

    2009-12-01

    Composites of the alumino silicate mineral kaolinite, with the conducting polymers polypyrrole and polyaniline have been successfully synthesised. In doing so hybrid materials have been produced in which the high surface area of the mineral is retained, whilst also incorporating the desired chemical and physical properties of the polymer. Scanning electron microscopy shows polypyrrole coatings to comprise of individual polymer spheres, approximately 10 to 15 nm in diameter. The average size of the polymer spheres of polyaniline was observed to be approximately 5 nm in diameter. These spheres fuse together in a continuous sheet to coat the kaolinite platelets in their entirety. The reduction of silver ions to metallic silver nanoparticles onto the redox active surface of the polymers has also been successful, and thus imparts anti-microbial properties to the hybrid materials. This gives rise to further applications requiring the inhibition of microbial growth. The chemical and physical characterization of the hybrid materials has been undertaken through scanning electron microscopy, energy dispersive spectroscopy, electrical conductivity, cyclic voltammetry, X-ray diffraction, infra red spectroscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis and the testing of their anti-microbial activity.

  10. Removal of Pb(II) from aqueous solution using modified and unmodified kaolinite clay

    International Nuclear Information System (INIS)

    Jiang Mingqin; Wang Qingping; Jin Xiaoying; Chen Zuliang

    2009-01-01

    Modified kaolinite clay with 25% (w/w) aluminium sulphate and unmodified kaolin were investigated as adsorbents to remove Pb(II) from aqueous solution. The results show that amount of Pb(II) adsorbed onto modified kaolin (20 mg/g) was more than 4.5-fold than that adsorbed onto unmodified kaolin (4.2 mg/g) under the optimized condition. In addition, the linear Langmuir and Freundlich models were used to describe equilibrium isotherm. It is observed that the data from both adsorbents fitted well to the Langmuir isotherm. The kinetic adsorption of modified and unmodified kaolinite clay fitted well to the pseudo-second-order model. Furthermore, both modified and unmodified kaolinite clay were characterized by X-ray diffraction, Fourier transform infrared (FT-IR) and scanning electron microscope (SEM). Finally, both modified and unmodified kaolinite clay were used to remove metal ions from real wastewater, and results show that higher amount of Pb(II) (the concentration reduced from 178 to 27.5 mg/L) and other metal ions were removed by modified kaolinite clay compared with using unmodified adsorbent (the concentration reduced from 178 to 168 mg/L).

  11. Preparation and characterization of photoactive composite kaolinite/TiO2

    International Nuclear Information System (INIS)

    Mamulova Kutlakova, K.; Tokarsky, J.; Kovar, P.; Vojteskova, S.; Kovarova, A.; Smetana, B.; Kukutschova, J.; Capkova, P.; Matejka, V.

    2011-01-01

    Preparation of nanocomposite kaolinite/TiO 2 , using hydrolysis of titanyl sulfate in the presence of kaolin was addressed. A variable (kaolin)/(titanyl sulfate) ratio has been used in order to achieve the desired TiO 2 content in prepared nanocomposites. Calcination of the composites at 600 deg, C led to the transformation of the kaolinite to metakaolinite and to origination of metakaolinite/TiO 2 composites. The prepared samples were investigated using X-ray fluorescence spectroscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetry and diffuse reflectance spectroscopy in the UV-VIS region. Structural ordering of TiO 2 on the kaolinite particle surface was modeled using empirical force field atomistic simulations in the Material Studio modeling environment. Photodegradation activity of the composites prepared was evaluated by the discoloration of Acid Orange 7 aqueous solution.

  12. Page 170 Use of Electronic Resources by Undergraduates in Two ...

    African Journals Online (AJOL)

    undergraduate students use electronic resources such as NUC virtual library, HINARI, ... web pages articles from magazines, encyclopedias, pamphlets and other .... of Nigerian university libraries have Internet connectivity, some of the system.

  13. Neptunium(V) sorption on kaolinite

    Energy Technology Data Exchange (ETDEWEB)

    Amayri, S.; Jermolajev, A.; Reich, T. [Mainz Univ. (Germany). Inst. of Nuclear Chemistry

    2011-07-01

    The sorption behavior of neptunium(V) onto the clay mineral kaolinite was studied in batch experiments under different experimental conditions: [Np(V)] = 7 x 10{sup -12}-8 x 10{sup -6} M, solid-to-liquid ratio 2-20 g L{sup -1}, I = 0.1 and 0.01 M NaClO{sub 4}, pH = 6-10, ambient air and Ar atmosphere. The short-lived isotope {sup 239}Np (T{sub 1/2} = 2.36 d) was used instead of {sup 237}Np (T{sub 1/2} = 2.14 x 10{sup 6} a) to study the sorption behavior of Np(V) at environmentally-relevant concentrations, i.e., 7 x 10{sup -12} M Np. In addition, {sup 239}Np(V) served as tracer to measure sorption isotherms over six orders of magnitude in Np concentration (4.8 x 10{sup -12}-1.0 x 10{sup -4} M). The results show that Np(V) sorption on kaolinite is strongly influenced by pH, CO{sub 2}, and ionic strength. The sorption of 8 x 10{sup -6} M Np(V) at pH 9.0, and ionic strength of 0.1 M NaClO{sub 4} was proportional to the solid-to-liquid ratio of kaolinite in the range of 2-10 g L{sup -1}. In the absence of CO{sub 2}, the Np(V) uptake increased continuously with increasing pH value up to 97% at pH 10. Under ambient CO{sub 2}, the sorption of Np decreased above pH 8 up to zero at pH 10. An increase of Np(V) concentration from 7 x 10{sup -12} to 8 x 10{sup -6} M resulted in a shift of the sorption pH edge by up to one pH unit to higher pH values. The ionic strength influenced the Np(V) sorption onto kaolinite only in the presence of ambient CO{sub 2}. Under Ar atmosphere the sorption of Np(V) was independent from ionic strength, indicating the formation of inner-sphere complexes of Np(V) with kaolinite. Time-dependent batch experiments at pH 9.0 under ambient CO{sub 2} showed that the sorption of Np(V) on kaolinite is fast and fully reversible over six orders in Np(V) concentration. (orig.)

  14. Utilisation of Electronic Information Resources By Lecturers in ...

    African Journals Online (AJOL)

    This study assesses the use of information resources, specifically, electronic databases by lecturers/teachers in Universities and Colleges of Education in South Western Nigeria. Information resources are central to teachers' education. It provides lecturers/teachers access to information that enhances research and ...

  15. Preservation and conservation of electronic information resources of ...

    African Journals Online (AJOL)

    The major holdings of the broadcast libraries of the Nigerian Television Authority (NTA) are electronic information resources; therefore, providing safe places for general management of these resources have aroused interest in the industry in Nigeria for sometimes. The need to study the preservation and conservation of ...

  16. Using XML Technologies to Organize Electronic Reference Resources

    OpenAIRE

    Huser, Vojtech; Del Fiol, Guilherme; Rocha, Roberto A.

    2005-01-01

    Provision of access to reference electronic resources to clinicians is becoming increasingly important. We have created a framework for librarians to manage access to these resources at an enterprise level, rather than at the individual hospital libraries. We describe initial project requirements, implementation details, and some preliminary results.

  17. Euler European Libraries and Electronic Resources in Mathematical Sciences

    CERN Document Server

    The Euler Project. Karlsruhe

    The European Libraries and Electronic Resources (EULER) Project in Mathematical Sciences provides the EulerService site for searching out "mathematical resources such as books, pre-prints, web-pages, abstracts, proceedings, serials, technical reports preprints) and NetLab (for Internet resources), this outstanding engine is capable of simple, full, and refined searches. It also offers a browse option, which responds to entries in the author, keyword, and title fields. Further information about the Project is provided at the EULER homepage.

  18. Building an electronic resource collection a practical guide

    CERN Document Server

    Lee, Stuart D

    2004-01-01

    This practical book guides information professionals step-by-step through building and managing an electronic resource collection. It outlines the range of electronic products currently available in abstracting and indexing, bibliographic, and other services and then describes how to effectively select, evaluate and purchase them.

  19. EXAFS study of plutonium sorption onto kaolinite

    International Nuclear Information System (INIS)

    Reich, T.Y.; Banik, L.; Buda, R.A.; Amayri, S.; Drebert, J.; Kratz, J.V.; Trautmann, N.; Reich, T.; Ageev, A.L.; Korshunov, M.E.

    2007-01-01

    The uptake mechanism of plutonium by kaolinite was investigated by applying X-ray absorption spectroscopy to batch sorption samples (total Pu concentrations 1 and 10 μM; 4 g kaolinite/L in 0.1 M NaClO 4 ; 1 ≤ pH ≤ 9; presence and absence of ambient CO 2 ). For XAFS measurements, one sample was prepared from a Pu(III) solution at pH 6 under argon atmosphere. Three samples were obtained by sorption of Pu(IV) at pH I, 4, and 9 in an air-equilibrated system. The Pu L III -edge XANES spectra indicated that in all samples, including the Pu(III) sample, plutonium is sorbed at the kaolinite surface as Pu(IV). The Pu L III -edge k 3 -weighted EXAFS spectra showed eight oxygen atoms at an average Pu-O distance of 2.3 angstrom. Two Pu atoms were detected at ∼ 3.7 angstrom in all spectra, indicating the formation of polynuclear Pu(IV) species at the kaolinite surface. For the sample prepared from Pu(III) solution, an additional Pu-O shell at 3.2 angstrom was observed. The spectra of samples prepared from Pu(IV) included a Pu-Al/Si co-ordination shell at approximately 3.6 angstrom, indicating formation of inner-sphere sorption complexes. The structural models used in the least-squares fits were confirmed by an alternative EXAFS data analysis approach based on a modified Tikhonov regularization method. (authors)

  20. Molecular Treatment of Nano-Kaolinite Generations.

    Science.gov (United States)

    Táborosi, Attila; Szilagyi, Robert K; Zsirka, Balázs; Fónagy, Orsolya; Horváth, Erzsébet; Kristóf, János

    2018-06-18

    A procedure is developed for defining a compositionally and structurally realistic, atomic-scale description of exfoliated clay nanoparticles from the kaolinite family of phylloaluminosilicates. By use of coordination chemical principles, chemical environments within a nanoparticle can be separated into inner, outer, and peripheral spheres. The edges of the molecular models of nanoparticles were protonated in a validated manner to achieve charge neutrality. Structural optimizations using semiempirical methods (NDDO Hamiltonians and DFTB formalism) and ab initio density functionals with a saturated basis set revealed previously overlooked molecular origins of morphological changes as a result of exfoliation. While the use of semiempirical methods is desirable for the treatment of nanoparticles composed of tens of thousands of atoms, the structural accuracy is rather modest in comparison to DFT methods. We report a comparative survey of our infrared data for untreated crystalline and various exfoliated states of kaolinite and halloysite. Given the limited availability of experimental techniques for providing direct structural information about nano-kaolinite, the vibrational spectra can be considered as an essential tool for validating structural models. The comparison of experimental and calculated stretching and bending frequencies further justified the use of the preferred level of theory. Overall, an optimal molecular model of the defect-free, ideal nano-kaolinite can be composed with respect to stationary structure and curvature of the potential energy surface using the PW91/SVP level of theory with empirical dispersion correction (PW91+D) and polarizable continuum solvation model (PCM) without the need for a scaled quantum chemical force field. This validated theoretical approach is essential in order to follow the formation of exfoliated clays and their surface reactivity that is experimentally unattainable.

  1. Organizational matters of competition in electronic educational resources

    Directory of Open Access Journals (Sweden)

    Ирина Карловна Войтович

    2015-12-01

    Full Text Available The article examines the experience of the Udmurt State University in conducting competitions of educational publications and electronic resources. The purpose of such competitions is to provide methodological support to educational process. The main focus is on competition of electronic educational resources. The technology of such contests is discussed through detailed analysis of the main stages of the contest. It is noted that the main task of the preparatory stage of the competition is related to the development of regulations on competition and the definition of criteria for selection of the submitted works. The paper also proposes a system of evaluation criteria of electronic educational resources developed by members of the contest organizing committee and jury members. The article emphasizes the importance of not only the preparatory stages of the competition, but also measures for its completion, aimed at training teachers create quality e-learning resources.

  2. Kaolinite as an in situ dosimeter for past radionuclide migration at the Earth's surface

    International Nuclear Information System (INIS)

    Allard, T.; Muller, J.-P.

    1998-01-01

    The origin of 3 types of point defects (A-, Aminutes or feet- and B-centers) in kaolinite, due to natural irradiation and detected by electron paramagnetic resonance spectroscopy (EPR), has been demonstrated by artificial irradiation. The potential use of tracing the dynamics of the transfer of radionuclides through A-centers (i.e. the most stable centers) was qualitatively tested on different low-temperature alteration systems, some associated with U-concentrations. This paper proposes a quantitative approach to the reconstruction of the past migration of radionuclides by dosimetry of A-centers. With this aim in mind, the efficiency of α- and γ-radiations to produce A-centers was determined by experimental irradiation. Parameters extracted from A-center growth curves, together with their relationship with a parameter describing the degree of order of kaolinite, permitted (i) a definition to be made of the dose range in which a given kaolinite could be used as a dosimeter and (ii) the quantitative derivation of U-concentration from the cumulative dose (paleodose) of kaolinites. This was achieved by a formalism that accounted for the contribution of natural radiosources to the production of A-centers. The formalism was applied to the Nopal I U-deposit (Chihuhua, Mexico), considered as a natural analogue of a high level nuclear waste repository. Irrespective of the scenario considered, in terms of kaolinite age and of degree of isotopic disequilibrium in the system, A-center dosimetry permitted the determination of past occurrences of U which were several orders of magnitude higher than the present-day measured U-concentrations. Furthermore, this approach also provided evidence for several previous episodes of U-migration. EPR spectroscopy is thus a unique tool for the quantitative, indirect assessment of past radionuclide migration in the geosphere and kaolinite is a reliable in-situ dosimeter. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights

  3. Why and How to Measure the Use of Electronic Resources

    Directory of Open Access Journals (Sweden)

    Jean Bernon

    2008-11-01

    Full Text Available A complete overview of library activity implies a complete and reliable measurement of the use of both electronic resources and printed materials. This measurement is based on three sets of definitions: document types, use types and user types. There is a common model of definitions for printed materials, but a lot of questions and technical issues remain for electronic resources. In 2006 a French national working group studied these questions. It relied on the COUNTER standard, but found it insufficient and pointed out the need for local tools such as web markers and deep analysis of proxy logs. Within the French national consortium COUPERIN, a new working group is testing ERMS, SUSHI standards, Shibboleth authentication, along with COUNTER standards, to improve the counting of the electronic resources use. At this stage this counting is insufficient and its improvement will be a European challenge for the future.

  4. Access to electronic resources by visually impaired people

    Directory of Open Access Journals (Sweden)

    Jenny Craven

    2003-01-01

    Full Text Available Research into access to electronic resources by visually impaired people undertaken by the Centre for Research in Library and Information Management has not only explored the accessibility of websites and levels of awareness in providing websites that adhere to design for all principles, but has sought to enhance understanding of information seeking behaviour of blind and visually impaired people when using digital resources.

  5. Practical guide to electronic resources in the humanities

    CERN Document Server

    Dubnjakovic, Ana

    2010-01-01

    From full-text article databases to digitized collections of primary source materials, newly emerging electronic resources have radically impacted how research in the humanities is conducted and discovered. This book, covering high-quality, up-to-date electronic resources for the humanities, is an easy-to-use annotated guide for the librarian, student, and scholar alike. It covers online databases, indexes, archives, and many other critical tools in key humanities disciplines including philosophy, religion, languages and literature, and performing and visual arts. Succinct overviews of key eme

  6. Discipline, availability of electronic resources and the use of Finnish National Electronic Library - FinELib

    Directory of Open Access Journals (Sweden)

    Sanna Torma

    2004-01-01

    Full Text Available This study elaborated relations between digital library use by university faculty, users' discipline and the availability of key resources in the Finnish National Electronic Library (FinELib, Finnish national digital library, by using nationwide representative survey data. The results show that the perceived availability of key electronic resources by researchers in FinELib was a stronger predictor of the frequency and purpose of use of its services than users' discipline. Regardless of discipline a good perceived provision of central resources led to a more frequent use of FinELib. The satisfaction with the services did not vary with the discipline, but with the perceived availability of resources.

  7. Access to electronic information resources by students of federal ...

    African Journals Online (AJOL)

    The paper discusses access to electronic information resources by students of Federal Colleges of Education in Eha-Amufu and Umunze. Descriptive survey design was used to investigate sample of 526 students. Sampling technique used was a Multi sampling technique. Data for the study were generated using ...

  8. Electronic Commerce Resource Centers. An Industry--University Partnership.

    Science.gov (United States)

    Gulledge, Thomas R.; Sommer, Rainer; Tarimcilar, M. Murat

    1999-01-01

    Electronic Commerce Resource Centers focus on transferring emerging technologies to small businesses through university/industry partnerships. Successful implementation hinges on a strategic operating plan, creation of measurable value for customers, investment in customer-targeted training, and measurement of performance outputs. (SK)

  9. ANALYTICAL REVIEW OF ELECTRONIC RESOURCES FOR THE STUDY OF LATIN

    Directory of Open Access Journals (Sweden)

    Olena Yu. Balalaieva

    2014-04-01

    Full Text Available The article investigates the current state of development of e-learning content in the Latin language. It is noted that the introduction of ICT in the educational space has expanded the possibility of studying Latin, opened access to digital libraries resources, made it possible to use scientific and educational potential and teaching Latin best practices of world's leading universities. A review of foreign and Ukrainian information resources and electronic editions for the study of Latin is given. Much attention was paid to the didactic potential of local and online multimedia courses of Latin, electronic textbooks, workbooks of interactive tests and exercises, various dictionaries and software translators, databases and digital libraries. Based on analysis of the world market of educational services and products the main trends in the development of information resources and electronic books are examined. It was found that multimedia courses with interactive exercises or workbooks with interactive tests, online dictionaries and translators are the most widely represented and demanded. The noticeable lagging of Ukrainian education and computer linguistics in quantitative and qualitative measures in this industry is established. The obvious drawback of existing Ukrainian resources and electronic editions for the study of Latin is their noninteractive nature. The prospects of e-learning content in Latin in Ukraine are outlined.

  10. Adoption and use of electronic information resources by medical ...

    African Journals Online (AJOL)

    This study investigated the adoption and use of electronic information resources by medical science students of the University of Benin. The descriptive survey research design was adopted for the study and 390 students provided the data. Data collected were analysed with descriptive Statistics(Simple percentage and ...

  11. Modern ICT Tools: Online Electronic Resources Sharing Using Web ...

    African Journals Online (AJOL)

    Modern ICT Tools: Online Electronic Resources Sharing Using Web 2.0 and Its Implications For Library And Information Practice In Nigeria. ... The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat Reader). If you would like more ...

  12. Technical Communicator: A New Model for the Electronic Resources Librarian?

    Science.gov (United States)

    Hulseberg, Anna

    2016-01-01

    This article explores whether technical communicator is a useful model for electronic resources (ER) librarians. The fields of ER librarianship and technical communication (TC) originated and continue to develop in relation to evolving technologies. A review of the literature reveals four common themes for ER librarianship and TC. While the…

  13. Polyaniline/TiO{sub 2}/kaolinite: The composite material with high electrical anisotropy

    Energy Technology Data Exchange (ETDEWEB)

    Tokarský, Jonáš, E-mail: jonas.tokarsky@vsb.cz [Nanotechnology Centre, VŠB – Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava (Czech Republic); Neuwirthová, Lucie; Peikertová, Pavlína [Nanotechnology Centre, VŠB – Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava (Czech Republic); Kulhánková, Lenka [Faculty of Metallurgy and Materials Engineering, VŠB – Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava (Czech Republic); Mamulová Kutláková, Kateřina; Matějka, Vlastimil [Nanotechnology Centre, VŠB – Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava (Czech Republic); Čapková, Pavla [Faculty of Science, J.E. Purkyně University, České mládeže 8, 400 96 Ústí nad Labem (Czech Republic)

    2014-07-01

    Kaolinite–TiO{sub 2} nanocomposite matrix (KATI) coated with polyaniline (PANI) layer has been prepared in powder form and pressed into tablets. The conductivity was studied in dependence on (1) wt.% of TiO{sub 2} in KATI matrix and (2) thermal pre-treatment of KATI matrix. The anisotropy factor α, i.e. the ratio of in-plane conductivity and conductivity in the direction perpendicular to the tablet plane, was found to be very high for PANI/KATI tablet (α is of the order of 10{sup 3}–10{sup 4}) in comparison with pure PANI tablet (α is of the order of 10{sup 2}). Structure has been studied using Raman spectroscopy, X-ray diffraction analysis, scanning electron microscopy and molecular modeling. The possibility of using the tablets as a load sensors have been tested and tablets pressed from composites containing calcined KATI seem to be promising material for this purpose. - Graphical abstract: Tablets pressed from powder form of polyaniline/TiO{sub 2}/kaolinite composites exhibit very high electrical anisotropy and were found to be suitable as load sensors. - Highlights: • Kaolinite/TiO{sub 2}/polyaniline composites exhibit very high electrical anisotropy. • Presence of TiO{sub 2} helps polyaniline to fully cover the kaolinite particles. • Tablets pressed from these composites can be used as load sensors. • Calcination of kaolinite/TiO{sub 2} matrix improves the sensing properties.

  14. Polyaniline/TiO2/kaolinite: The composite material with high electrical anisotropy

    International Nuclear Information System (INIS)

    Tokarský, Jonáš; Neuwirthová, Lucie; Peikertová, Pavlína; Kulhánková, Lenka; Mamulová Kutláková, Kateřina; Matějka, Vlastimil; Čapková, Pavla

    2014-01-01

    Kaolinite–TiO 2 nanocomposite matrix (KATI) coated with polyaniline (PANI) layer has been prepared in powder form and pressed into tablets. The conductivity was studied in dependence on (1) wt.% of TiO 2 in KATI matrix and (2) thermal pre-treatment of KATI matrix. The anisotropy factor α, i.e. the ratio of in-plane conductivity and conductivity in the direction perpendicular to the tablet plane, was found to be very high for PANI/KATI tablet (α is of the order of 10 3 –10 4 ) in comparison with pure PANI tablet (α is of the order of 10 2 ). Structure has been studied using Raman spectroscopy, X-ray diffraction analysis, scanning electron microscopy and molecular modeling. The possibility of using the tablets as a load sensors have been tested and tablets pressed from composites containing calcined KATI seem to be promising material for this purpose. - Graphical abstract: Tablets pressed from powder form of polyaniline/TiO 2 /kaolinite composites exhibit very high electrical anisotropy and were found to be suitable as load sensors. - Highlights: • Kaolinite/TiO 2 /polyaniline composites exhibit very high electrical anisotropy. • Presence of TiO 2 helps polyaniline to fully cover the kaolinite particles. • Tablets pressed from these composites can be used as load sensors. • Calcination of kaolinite/TiO 2 matrix improves the sensing properties

  15. Kaolinite: a natural radiations dosemeter. Application to past radioelement migrations tracing in the geosphere

    International Nuclear Information System (INIS)

    Allard, Thierry

    1994-01-01

    The efficiency of the processes regulating the mobility of the radioelements in the geosphere can be assessed by the study of past migrations of uranium. For that geochemical purpose, it can be used mineral tracers like kaolinite, which records past contacts with radioelements as radiation-induced defects. Three radiation-induced centers had been identified in kaolinite by means of electron paramagnetic resonance, i.e. the A-, A'- and B-centers, and interpreted as hole centers located on oxygen atoms of the structure. The A-center is stable at the scale of geological periods. Consequently, it could be directly used to measure paleo-doses, that are related to the past occurrence of radioelements. This works states the potentialities of kaolinite as a dosimeter for the study or past migrations of uranium in the geosphere: - Experimental irradiations: we studied the effects of the main natural radiations (alpha and gamma) within a dose range consistent with that occurring in geo-systems at the Earth surface. We simulated these radiation effects by irradiating natural reference kaolinites with He + ions provided by the ARAMIS particle accelerator (Orsay) and a 60 Co source (CENG, Grenoble), respectively. We took into account the natural variability of kaolinites in terms of crystalline disorder and chemical (Fe 3+ ) or mineralogical (illite, smectite) impurities. It is confirmed that the sensitivity of the radiation-induced centers decreases in the order B>A>A'. The dosimetry curve of the A center can be described with an exponential function constrained by two parameters (the concentration at saturation and the efficiency coefficient) which are correlated. These dosimetry parameters are also correlated with the crystalline order of the kaolinites, which suggests the possibility to assess them by a measurement of crystalline disorder (with EPR). Moreover, the alpha irradiations of illite and of smectite evidenced radiation centers, which can disturb the EPR

  16. Characterization of the natural kaolinite KGa-1b

    International Nuclear Information System (INIS)

    Puukko, E.; Hakanen, M.

    2003-05-01

    Kaolinite is a common mineral on the surfaces of fractures in the rock. The sorption of europium and americium on kaolinite has been studied in a previous study (Puukko and Hakanen, 2001) using a natural kaolinite, KGa-1b (from the Clay Mineral Society, USA). Before experiments the kaolinite was washed with acid (HCl). The washing with acid removed iron but not TiO 2 . Surface complexation model has been applied to model the acid base reactions of kaolinite and the sorption of americium and europium on the kaolinite. In the present work the sorption of europium on the natural kaolinite KGa-1b was studied. The characterization of the natural kaolinite KGa- 1b is needed in the modelling of the sorption experiments. The iron impurities in the kaolinite were extracted with phase selective solutions to determine if the iron was amorphous and crystalline. The dissociation constants of kaolinite KGa-1b were determined by acid base titration in 0.05 M, 0.1 M and 0.5 M NaNO 3 solutions by two methods: a continuous titration and a batch titration. The solutions of the batch titrations were analysed for dissolved cations and silica and lanthanides at the laboratory of the Geological Survey of Finland (GSF). The loss in ignition of the KGa-1b was 14.3 w-% according to the Clay Mineral Society. The possible presence of humic acids was investigated at the GSF using thermogravimetry, X-ray diffraction and IR spectrometry and in the Laboratory of Physical Chemistry by measuring IR-absorption of gases released from a heated sample. The kaolinite KGa-1b contains a small quantity of iron. The phase selective extraction of amorphous iron gave almost same results as crystalline iron. The quantities of pure iron oxide phases of the total iron content was very low. The thermogravimetry and XRD analysis of the kaolinite KGa-1b indicated no presence of organic impurities, especially humic acids. The sensitivity of the IR analysis was not high enough to detect humic acids in the kaolinite

  17. Kaolinitic clay-based grouting demonstration

    International Nuclear Information System (INIS)

    McCloskey, A.L.; Barry, C.J.; Wilmoth, R.

    1997-01-01

    An innovative Kaolinitic Clay-Based Grouting Demonstration was performed under the Mine Waste Technology Program (MWTP), funded by the U.S. Environmental Protection Agency (EPA) and jointly administered by the EPA and the U.S. Department of Energy (DOE). The objective of the technology was to demonstrate the effectiveness of kaolinitic clay-based grouting in reducing/eliminating infiltration of surface and shallow groundwater through fractured bedrock into underground mine workings. In 1993, the Mike Horse Mine was selected as a demonstration site for the field implementation and evaluation of the grouting technology. The mine portal discharge ranged between 114 to 454 liters per minute (30 to 120 gpm) of water containing iron, zinc, manganese, and cadmium at levels exceeding the National Drinking Water Maximum Contaminant Levels. The grout formulation was designed by the developer Morrison Knudsen Corporation/Spetstamponazhgeologia (MK/STG), in May 1994. Grout injection was performed by Hayward Baker, Inc. under the directive of MSE Technology Applications, Inc. (MSE-TA) during fall of 1994. The grout was injected into directionally-drilled grout holes to form a grout curtain at the project site. Post grout observations suggest the grout was successful in reducing the infiltration of the surface and shallow groundwater from entering the underground mine workings. The proceeding paper describes the demonstration and technology used to form the subsurface barrier in the fracture system

  18. Strontium adsorption and penetration in kaolinite at low Sr

    NARCIS (Netherlands)

    Ning, Zigong; Ishiguro, Munehide; Koopal, Luuk K.; Sato, Tsutomu; Kashiwagi, Junichi

    2017-01-01

    Behavior of radioactive strontium (Sr2+) in contaminated soils is an important issue in relation to nuclear power plant accidents. The Sr2+ adsorption on kaolinite and its migration in a kaolinite soil were investigated because toxic effects of radioactive Sr2+ have been found to be very severe for

  19. MODEL OF AN ELECTRONIC EDUCATIONAL RESOURCE OF NEW GENERATION

    Directory of Open Access Journals (Sweden)

    Anatoliy V. Loban

    2016-01-01

    Full Text Available The mathematical structure of the modular architecture of an electronic educational resource (EER of new generation, which allows to decompose the process of studying the subjects of the course at a hierarchically ordered set of data (knowledge and procedures for manipulating them, to determine the roles of participants of process of training of and technology the development and use of EOR in the study procrate.

  20. The growth of multi-walled carbon nanotubes on natural clay minerals (kaolinite, nontronite and sepiolite)

    International Nuclear Information System (INIS)

    Pastorková, K.; Jesenák, K.; Kadlečíková, M.; Breza, J.; Kolmačka, M.; Čaplovičová, M.; Lazišťan, F.; Michalka, M.

    2012-01-01

    The suitability of clay minerals - kaolinite, nontronite and sepiolite - is studied for synthesis of nanocomposites based on carbon nanotubes. Particles of iron were used as catalysts. Prior to synthesis, kaolinite and sepiolite were doped by the catalytically active metal, whereas in the case of nontronite the presence was used of this metal in the matrix of this mineral. Synthesis of CNTs was performed by hot filament chemical vapor deposition method. The produced nanocomposites were examined by transmission and scanning electron microscopies and energy dispersive X-ray spectroscopy. The experiment verified the potential of the three microcrystalline phyllosilicates for the growth of carbon nanotubes. Under the same technology conditions, the type of catalyst carrier affects the morphology and structure of the nanotube product markedly.

  1. End-of-life resource recovery from emerging electronic products

    DEFF Research Database (Denmark)

    Parajuly, Keshav; Habib, Komal; Cimpan, Ciprian

    2016-01-01

    Integrating product design with appropriate end-of-life (EoL) processing is widely recognized to have huge potentials in improving resource recovery from electronic products. In this study, we investigate both the product characteristics and EoL processing of robotic vacuum cleaner (RVC), as a case...... of emerging electronic product, in order to understand the recovery fate of different materials and its linkage to product design. Ten different brands of RVC were dismantled and their material composition and design profiles were studied. Another 125 RVCs (349 kg) were used for an experimental trial...... at a conventional ‘shred-and-separate’ type preprocessing plant in Denmark. A detailed material flow analysis was performed throughout the recycling chain. The results show a mismatch between product design and EoL processing, and the lack of practical implementation of ‘Design for EoL’ thinking. In the best...

  2. Analysis of Human Resources Management Strategy in China Electronic Commerce Enterprises

    Science.gov (United States)

    Shao, Fang

    The paper discussed electronic-commerce's influence on enterprise human resources management, proposed and proved the human resources management strategy which electronic commerce enterprise should adopt from recruitment strategy to training strategy, keeping talent strategy and other ways.

  3. Effects of Electronic Information Resources Skills Training for Lecturers on Pedagogical Practices and Research Productivity

    Science.gov (United States)

    Bhukuvhani, Crispen; Chiparausha, Blessing; Zuvalinyenga, Dorcas

    2012-01-01

    Lecturers use various electronic resources at different frequencies. The university library's information literacy skills workshops and seminars are the main sources of knowledge of accessing electronic resources. The use of electronic resources can be said to have positively affected lecturers' pedagogical practices and their work in general. The…

  4. Electronic Resources and Mission Creep: Reorganizing the Library for the Twenty-First Century

    Science.gov (United States)

    Stachokas, George

    2009-01-01

    The position of electronic resources librarian was created to serve as a specialist in the negotiation of license agreements for electronic resources, but mission creep has added more functions to the routine work of electronic resources such as cataloging, gathering information for collection development, and technical support. As electronic…

  5. Evaluation of the nanoparticle treatment effect on the development of nanocomposite resin epoxy/kaolinite;Avaliacao do efeito do tratamento da nanoparticula no desenvolvimento de nanocomposito resina epoxi/caulinita

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Tharsia C.C.; Mendonca, Rannier M., E-mail: tharsia@gmail.co [Universidade Federal do Rio Grande do Norte (PPGCEM/UFRN), Natal (Brazil). Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais; Ito, Edson N; Melo, Jose D.D.; Paskocimas, Carlos A., E-mail: ito@ufrnet.b [Universidade Federal do Rio Grande do Norte (DEMat/UFRN), Natal (Brazil). Dept. de Engenharia de Materiais

    2009-07-01

    The nanocomposites formed from polymer matrices and mineral clays have been studied since the decade of 60s when Blumstein demonstrated the intercalation the polymer molecules between lamellae of montmorillonite. The application of the kaolinite in nanocomposite polymeric is rare, however the kaolinite is expandable and it is possible to do the process of the superficial functionalization. The present work demonstrates that after leaching process of the kaolinite through a chemical treatment with hydrogen peroxide combined with acid solutions the kaolinite inside presents a surface activated with good resulted of dispersion of a polymers matrix by a mechanical agitation, in high-energy mill. The samples had been characterized by x-ray diffraction, thermogravimetry (TGA) and transmission electron microscopy (TEM). The results showed the potential of using the functionalized kaolinite as an agent of reinforcement in polymer nanocomposites. (author)

  6. Testing the stability of magnetic iron oxides/kaolinite nanocomposite under various pH conditions

    Science.gov (United States)

    Tokarčíková, Michaela; Tokarský, Jonáš; Kutláková, Kateřina Mamulová; Seidlerová, Jana

    2017-09-01

    Magnetically modified clays containing iron oxides nanoparticles (FexOy NPs) are low-cost and environmentally harmless materials suitable for sorption of pollutants from wastewaters. Stability of this smart material was evaluated both experimentally and theoretically using molecular modelling. Original kaolinite and prepared FexOy/kaolinite nanocomposite were characterized using X-ray fluorescence spectroscopy, X-ray powder diffraction, infrared spectroscopy, and transmission electron microscopy, and the stability was studied using leaching tests performed according to the European technical standard EN 12457-2 in deionized water and extraction agents with varying pH (2, 4, 9, and 11). The influence of pH on amount of FexOy NPs released from the composite and amount of the basic elements released from the kaolinite structure was studied using inductively coupled plasma atomic emission spectroscopy. All experiments proved that the magnetic properties of the nanocomposite will not change even after leaching in extraction agents with various pH.

  7. Electronic Document Management: A Human Resource Management Case Study

    Directory of Open Access Journals (Sweden)

    Thomas Groenewald

    2004-11-01

    Full Text Available This case study serve as exemplar regarding what can go wrong with the implementation of an electronic document management system. Knowledge agility and knowledge as capital, is outlined against the backdrop of the information society and knowledge economy. The importance of electronic document management and control is sketched thereafter. The literature review is concluded with the impact of human resource management on knowledge agility, which includes references to the learning organisation and complexity theory. The intervention methodology, comprising three phases, follows next. The results of the three phases are presented thereafter. Partial success has been achieved with improving the human efficacy of electronic document management, however the client opted to discontinue the system in use. Opsomming Die gevalle studie dien as voorbeeld van wat kan verkeerd loop met die implementering van ’n elektroniese dokumentbestuur sisteem. Teen die agtergrond van die inligtingsgemeenskap en kennishuishouding word kennissoepelheid en kennis as kapitaal bespreek. Die literatuurstudie word afgesluit met die inpak van menslikehulpbronbestuur op kennissoepelheid, wat ook die verwysings na die leerorganisasie en kompleksietydsteorie insluit. Die metodologie van die intervensie, wat uit drie fases bestaan, volg daarna. Die resultate van die drie fases word vervolgens aangebied. Slegs gedeelte welslae is behaal met die verbetering van die menslike doeltreffendheid ten opsigte van elektroniese dokumentbestuur. Die klient besluit egter om nie voort te gaan om die huidige sisteem te gebruik nie.

  8. Application of Brazilian kaolinite clay as adsorbent to removal of U(VI) from aqueous solution: Kinetic and thermodynamic of cation-basic interactions

    International Nuclear Information System (INIS)

    Guerra, Denis L.; Leidens, Victor L.; Viana, Rubia R.; Airoldi, Claudio

    2010-01-01

    The compound N 1 -[3-(trimethoxysilyl)propyl]diethylenetriamine was anchored onto Amazon kaolinite surface by heterogeneous route. The modified and natural kaolinite samples were characterized by transmission electron microscopy, scanning electron microscopic, X-ray diffraction, and nuclear magnetic nuclei of 29 Si and 13 C. The well-defined peaks obtained in the 13 C NMR spectrum in the 5.0-62.1 ppm region confirmed the attachment of organic functional groups as pendant chains bonded into the porous clay. The ability of these materials to remove U(VI) from aqueous solution was followed by a series of adsorption isotherms adjusted to a Sips equation at room temperature and pH 4.0. The kinetic parameters analyzed by the Lagergren and Elovich models gave a good fit for a pseudo-second order reaction with k 2 values 16.0 and 25.1 mmol g -1 min -1 ranges for natural and modified kaolinite clays, respectively. The energetic effects caused by metal ion adsorption were determined through calorimetric titrations. - Graphical abstract: This investigation reports the use of original and modified kaolinites as alternative absorbents. The compound N-[3-trimethoxysilyl)propyl]diethylenetriamine was anchored onto Amazon kaolinite surface by heterogeneous route.

  9. Electronic Safety Resource Tools -- Supporting Hydrogen and Fuel Cell Commercialization

    Energy Technology Data Exchange (ETDEWEB)

    Barilo, Nick F.

    2014-09-29

    The Pacific Northwest National Laboratory (PNNL) Hydrogen Safety Program conducted a planning session in Los Angeles, CA on April 1, 2014 to consider what electronic safety tools would benefit the next phase of hydrogen and fuel cell commercialization. A diverse, 20-person team led by an experienced facilitator considered the question as it applied to the eight most relevant user groups. The results and subsequent evaluation activities revealed several possible resource tools that could greatly benefit users. The tool identified as having the greatest potential for impact is a hydrogen safety portal, which can be the central location for integrating and disseminating safety information (including most of the tools identified in this report). Such a tool can provide credible and reliable information from a trustworthy source. Other impactful tools identified include a codes and standards wizard to guide users through a series of questions relating to application and specific features of the requirements; a scenario-based virtual reality training for first responders; peer networking tools to bring users from focused groups together to discuss and collaborate on hydrogen safety issues; and a focused tool for training inspectors. Table ES.1 provides results of the planning session, including proposed new tools and changes to existing tools.

  10. Controlling user access to electronic resources without password

    Science.gov (United States)

    Smith, Fred Hewitt

    2015-06-16

    Described herein are devices and techniques for remotely controlling user access to a restricted computer resource. The process includes pre-determining an association of the restricted computer resource and computer-resource-proximal environmental information. Indicia of user-proximal environmental information are received from a user requesting access to the restricted computer resource. Received indicia of user-proximal environmental information are compared to associated computer-resource-proximal environmental information. User access to the restricted computer resource is selectively granted responsive to a favorable comparison in which the user-proximal environmental information is sufficiently similar to the computer-resource proximal environmental information. In at least some embodiments, the process further includes comparing user-supplied biometric measure and comparing it with a predetermined association of at least one biometric measure of an authorized user. Access to the restricted computer resource is granted in response to a favorable comparison.

  11. Radiation-Induced Defects in Kaolinite as Tracers of Past Occurrence of Radionuclides in a Natural Analogue of High Level Nuclear Waste Repository

    Science.gov (United States)

    Allard, T.; Fourdrin, C.; Calas, G.

    2007-05-01

    Understanding the processes controlling migrations of radioelements at the Earth's surface is an important issue for the long-term safety assessment of high level nuclear waste repositories (HLNWR). Evidence of past occurrence and transfer of radionuclides can be found using radiation-induced defects in minerals. Clay minerals are particularly relevant because of their widespread occurrence at the Earth's surface and their finely divided nature which provides high contact area with radioactive fluids. Owing to its sensitivity to radiations, kaolinite can be used as natural, in situ dosimeter. Kaolinite is known to contain radiation-induced defects which are detected by Electron Paramagnetic Resonance. They are differentiated by their nature, their production kinetics and their thermal stability. One of these defects is stable at the scale of geological periods and provides a record of past radionuclide occurrence. Based on artificial irradiations, a methodology has been subsequently proposed to determine paleodose cumulated by kaolinite since its formation. The paleodose can be used to derive equivalent radioelement concentrations, provided that the age of kaolinite formation can be constrained. This allows quantitative reconstruction of past transfers of radioelements in natural systems. An example is given for the Nopal I U-deposit (Chihuahua, Mexico), hosted in hydrothermally altered volcanic tufs and considered as analogue of the Yucca Mountain site. The paleodoses experienced by kaolinites were determined from the concentration of defects and dosimetry parameters of experimental irradiations. Using few geochemical assumption, a equivalent U-content responsible for defects in kaolinite was calculated from the paleodose, a dose rate balance and model ages of kaolinites constrained by tectonic phases. In a former study, the ages were assumptions derived from regional tectonic events. In thepresent study, ages of mineralization events are measured from U

  12. Adsorption properties of stearic acid onto untreated kaolinite | Sari ...

    African Journals Online (AJOL)

    The focus of the study is to investigate adsorption property and determine thermodynamic parameters for the adsorption of stearic acid onto untreated kaolinite at the temperatures of 25, 35 and 45 oC. The equilibrium adsorption isotherms were analyzed by linear Langmuir and Freundlich models. Adsorption experiments ...

  13. Calcination of kaolinite clay particles for cement production

    DEFF Research Database (Denmark)

    Gebremariam, Abraham Teklay; Yin, Chungen; Rosendahl, Lasse

    2014-01-01

    Kaolinite rich clay particles calcined under certain conditions can attain favorable pozzolanic properties and can be used to substitute part of the CO2 intensive clinker in cement production. To better guide calcination of a clay material, a transient one-dimensional single particle model...

  14. Polypropylene-modified kaolinite composites: Effect of chemical ...

    African Journals Online (AJOL)

    PP/kaolinite compounds were prepared by the melt intercalation method. The effects of modified clay on properties of the prepared composites were studied. The XRD results showed that the treatment with the ammonium salt caused the return to the initial state of the clay. The thermogravimetric analysis thermograms (TGA) ...

  15. Modeling of calcination of single kaolinitic clay particle

    DEFF Research Database (Denmark)

    Gebremariam, Abraham Teklay; Yin, Chungen; Rosendahl, Lasse

    The present work aims at modeling of the calcination (dehydroxylation) process of clay particles, specifically kaolinite, and its thermal transformation. For such purpose, 1D single particle calcination model was developed based on the concept of shrinking core model to assess the dehydroxylation...

  16. Porous Materials from Thermally Activated Kaolinite: Preparation, Characterization and Application

    Directory of Open Access Journals (Sweden)

    Jun Luo

    2017-06-01

    Full Text Available In the present study, porous alumina/silica materials were prepared by selective leaching of silicon/aluminum constituents from thermal-activated kaolinite in inorganic acid or alkali liquor. The correlations between the characteristics of the prepared porous materials and the dissolution properties of activated kaolinite were also investigated. The results show that the specific surface area (SSA of porous alumina/silica increases with silica/alumina dissolution, but without marked change of the BJH pore size. Furthermore, change in pore volume is more dependent on activation temperature. The porous alumina and silica obtained from alkali leaching of kaolinite activated at 1150 °C for 15 min and acid leaching of kaolinite activated at 850 °C for 15 min are mesoporous, with SSAs, BJH pore sizes and pore volumes of 55.8 m2/g and 280.3 m2/g, 6.06 nm and 3.06 nm, 0.1455 mL/g and 0.1945 mL/g, respectively. According to the adsorption tests, porous alumina has superior adsorption capacities for Cu2+, Pb2+ and Cd2+ compared with porous silica and activated carbon. The maximum capacities of porous alumina for Cu2+, Pb2+ and Cd2+ are 134 mg/g, 183 mg/g and 195 mg/g, respectively, at 30 °C.

  17. Adsorption of some radionuclides on kaolinite mineral surface

    International Nuclear Information System (INIS)

    Hafez, M.B.; Said, F.I.A.

    1986-01-01

    Fixation of 187 Cs(I), 144 Ce(III), 90 Sr(II), 233 U(VI), 239 Pu(IV) and 211 Am(III) from aqueous and phosphate media on kaolinite was studied. The fixation of the nuclides on the mineral was found to depend on the pH and the hydrolytic behaviour of the elements

  18. Coagulation processes of kaolinite and montmorillonite in calm, saline water

    Science.gov (United States)

    Zhang, Jin-Feng; Zhang, Qing-He; Maa, Jerome P.-Y.

    2018-03-01

    A three dimensional numerical model for simulating the coagulation processes of colloids has been performed by monitoring the time evolution of particle number concentration, the size distribution of aggregates, the averaged settling velocity, the collision frequency, and the collision efficiency in quiescent water with selected salinities. This model directly simulates all interaction forces between particles based on the lattice Boltzmann method (LBM) and the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory, and thus, can reveal the collision and coagulation processes of colloidal suspensions. Although using perfect spherical particles in the modeling, the results were compared with those for kaolinite and montmorillonite suspensions to demonstrate the capability of simulating the responses of these particles with highly irregular shape. The averaged settling velocity of kaolinite aggregates in quiescent saline water reached a maximum of 0.16 mm/s when the salinity increasing to about 3, and then, exhibited little dependence on salinity thereafter. Model simulations results (by choosing specific values that represent kaolinite's characteristics) indicate a similar trend: rapid decrease of the particle number concentration (i.e., rapidly flocculated, and thus, settling velocity also increases rapidly) when salinity increases from 0 to 2, and then, only increased slightly when salinity was further increased from 5 to 20. The collision frequency for kaolinite only decreases slightly with increasing salinity because that the fluid density and viscosity increase slightly in sea water. It suggests that the collision efficiency for kaolinite rises rapidly at low salinities and levels off at high salinity. For montmorillonite, the settling velocity of aggregates in quiescent saline water continuedly increases to 0.022 mm/s over the whole salinity range 0-20, and the collision efficiency for montmorillonite rises with increasing salinities.

  19. The Internet School of Medicine: use of electronic resources by medical trainees and the reliability of those resources.

    Science.gov (United States)

    Egle, Jonathan P; Smeenge, David M; Kassem, Kamal M; Mittal, Vijay K

    2015-01-01

    Electronic sources of medical information are plentiful, and numerous studies have demonstrated the use of the Internet by patients and the variable reliability of these sources. Studies have investigated neither the use of web-based resources by residents, nor the reliability of the information available on these websites. A web-based survey was distributed to surgical residents in Michigan and third- and fourth-year medical students at an American allopathic and osteopathic medical school and a Caribbean allopathic school regarding their preferred sources of medical information in various situations. A set of 254 queries simulating those faced by medical trainees on rounds, on a written examination, or during patient care was developed. The top 5 electronic resources cited by the trainees were evaluated for their ability to answer these questions accurately, using standard textbooks as the point of reference. The respondents reported a wide variety of overall preferred resources. Most of the 73 responding medical trainees favored textbooks or board review books for prolonged studying, but electronic resources are frequently used for quick studying, clinical decision-making questions, and medication queries. The most commonly used electronic resources were UpToDate, Google, Medscape, Wikipedia, and Epocrates. UpToDate and Epocrates had the highest percentage of correct answers (47%) and Wikipedia had the lowest (26%). Epocrates also had the highest percentage of wrong answers (30%), whereas Google had the lowest percentage (18%). All resources had a significant number of questions that they were unable to answer. Though hardcopy books have not been completely replaced by electronic resources, more than half of medical students and nearly half of residents prefer web-based sources of information. For quick questions and studying, both groups prefer Internet sources. However, the most commonly used electronic resources fail to answer clinical queries more than half

  20. Developing Humanities Collections in the Digital Age: Exploring Humanities Faculty Engagement with Electronic and Print Resources

    Science.gov (United States)

    Kachaluba, Sarah Buck; Brady, Jessica Evans; Critten, Jessica

    2014-01-01

    This article is based on quantitative and qualitative research examining humanities scholars' understandings of the advantages and disadvantages of print versus electronic information resources. It explores how humanities' faculty members at Florida State University (FSU) use print and electronic resources, as well as how they perceive these…

  1. Electronic resource management practical perspectives in a new technical services model

    CERN Document Server

    Elguindi, Anne

    2012-01-01

    A significant shift is taking place in libraries, with the purchase of e-resources accounting for the bulk of materials spending. Electronic Resource Management makes the case that technical services workflows need to make a corresponding shift toward e-centric models and highlights the increasing variety of e-formats that are forcing new developments in the field.Six chapters cover key topics, including: technical services models, both past and emerging; staffing and workflow in electronic resource management; implementation and transformation of electronic resource management systems; the ro

  2. Evaluation of mineral kaolinite present in portuguese clays for use in porcelain stoneware; Avaliacao do mineral caulinita presente em argilas portuguesas para uso em gres porcelanato

    Energy Technology Data Exchange (ETDEWEB)

    Luna da Silveira, G.C. [Instituto Federal do Rio Grande do Norte (IFRN), RN (Brazil); Acchar, W.; Gomes, U.U.; Luna da Silveira, R.V. [Universidade Federal do Rio Grnde do Norte (UFRN), RN (Brazil); Labrincha, A.; Miranda, C.M.P., E-mail: glebacoelli@hotmail.com [Universidade de Aveiro (Portugal)

    2016-07-01

    Kaolinite is a mineral from the kaolin, product resulting from transformation in depth of alumino silicate mineral type, such as feldspars, plagioclase and feldspars contained in the rocks. Clays are raw materials that have as main characteristic the plasticity property, which gives the product, after applying a certain pressure, a defined shape and an increase in the mechanical resistance when they become from green to dry and then to sintered. Given these characteristics, this paper analyzes the presence of the existing mineral kaolinite in two portuguese clays who are used in the preparation of formulations of porcelain stoneware tiles. The analyzes of the two clays were made by fluorescence x-ray diffraction of x-rays, thermal analysis, particle size and scanning electron microscopy, to better use of this mineral in the formulations. In both clays were found aluminum oxide, as well as mineral quartz, kaolinite and illite. (author)

  3. Electronic resources access and usage among the postgraduates of ...

    African Journals Online (AJOL)

    ... and usage among the postgraduates of a Nigerian University of Technology. ... faced by postgraduates in using e-resources include takes too much time to find, ... Resources, Access, Use, Postgraduat, Students, University, Technology, Nigeria ... By Country · List All Titles · Free To Read Titles This Journal is Open Access.

  4. Strategic Planning for Electronic Resources Management: A Case Study at Gustavus Adolphus College

    Science.gov (United States)

    Hulseberg, Anna; Monson, Sarah

    2009-01-01

    Electronic resources, the tools we use to manage them, and the needs and expectations of our users are constantly evolving; at the same time, the roles, responsibilities, and workflow of the library staff who manage e-resources are also in flux. Recognizing a need to be more intentional and proactive about how we manage e-resources, the…

  5. Fe(0)-Kaolinite (KGA2) interactions at 90° C under anoxic conditions

    International Nuclear Information System (INIS)

    Rivard, C.; Pelletier, M.; Montarges-Pelletier, E.; Michot, L.; Villieras, F.; Abdelmoula, M.; Karunakaran, C.; Ventelon, D.; Michau, N.

    2010-01-01

    Document available in extended abstract form only. Because of the use of steel containers for geological deposit of nuclear waste, it is of prime importance to understand the interaction mechanisms between the geological matrix, Callovo-Oxfordian argillite, and the steel container. In order to evidence the individual role of each different clay phase entering in the mineralogy of the Callovo-Oxfordian argillite, the iron-clay interactions were studied by the use of reference clays. The Georgia Kaolinite (KGa2) supplied by the Clay Mineral Society was selected to represent kaolinite minerals; as it has been extensively characterized in our laboratory. To reproduce the repository conditions, raw kaolinite was put in contact with powder metallic iron with a weight ratio fixed at 1/3 and a solid/liquid ratio of 1/20. Batch experiments were carried out in anoxic conditions at 90 deg. C in the presence of background electrolyte (NaCl 0.02 M.L -1 , CaCl 2 0.04 M.L -1 ) in Parr reactors for durations of one, three or nine months. Similar experiments without iron were carried out to show up the influence of iron on mineralogical transformations in such conditions. After, one, three or nine months, solid and liquid phases were separated by centrifugation and characterized by classical techniques combining chemical analyses, X-ray diffraction, Fourier Transform Infrared spectroscopy, scanning and transmission electron microscopy, XPS and Moessbauer analyses. Supplementary observation tools, based on the use of synchrotron radiation were used to reinforce the information about iron localisation and its status in individualized clay particles (Scanning Transmission X-ray Microscopy (STXM) and Micro-Xray Absorption Spectroscopy (μ-XAS)). Without iron, kaolinite KGa2 remains unchanged, from a mineralogical point of view, even after nine months in suspension. With iron, first results from one month experiments showed a decrease of pristine metallic iron as well as the apparition

  6. Amazon kaolinite functionalized with diethylenetriamine moieties for U(VI) removal: Thermodynamic of cation-basic interactions

    Energy Technology Data Exchange (ETDEWEB)

    Guerra, Denis L., E-mail: denis@cpd.ufmt.br [Universidade Federal de Mato Grosso, UFMT, Centro de Recursos Minerais, Cuiaba, Mato Grosso, 78060 900 (Brazil); Leidens, Victor L.; Viana, Rubia R. [Universidade Federal de Mato Grosso, UFMT, Centro de Recursos Minerais, Cuiaba, Mato Grosso, 78060 900 (Brazil); Airoldi, Claudio [Chemistry Institute, State University of Campinas, P.O. Box 6154, 13084-971 Campinas, Sao Paulo (Brazil)

    2010-08-15

    The compound N-[3-(trimethoxysilyl)propyl]diethylenetriamine (MPDET) was anchored onto Amazon kaolinite surface (KLT) by heterogeneous route. The modified and natural kaolinite clay samples were characterized by transmission electron microscopy (TEM), scanning electron microscopic (SEM), N{sub 2} adsorption, powder X-ray diffraction, thermal analysis, ion exchange capacities, and nuclear magnetic nuclei of {sup 29}Si and {sup 13}C. The well-defined peaks obtained in the {sup 13}C NMR spectrum in the 5.0-62.1 ppm region confirmed the attachment of organic functional groups as pendant chains bonded into the porous clay. The adsorption of uranyl on natural (KLT) and modified (KLT{sub MPDET}) kaolinite clays was investigated as a function of the solution pH, metal concentration, temperature, and ionic strength. The ability of these materials to remove U(VI) from aqueous solution was followed by a series of adsorption isotherms adjusted to a Sips equation at room temperature and pH 4.0. The maximum number of moles adsorbed was determined to be 8.37 x 10{sup -3} and 13.87 x 10{sup -3} mmol g{sup -1} for KLT and KLT{sub MPDET} at 298 K, respectively. The energetic effects ({Delta}{sub int}H, {Delta}{sub int}G, and {Delta}{sub int}S) caused by metal cations adsorption were determined through calorimetric titrations.

  7. Amazon kaolinite functionalized with diethylenetriamine moieties for U(VI) removal: Thermodynamic of cation-basic interactions

    International Nuclear Information System (INIS)

    Guerra, Denis L.; Leidens, Victor L.; Viana, Rubia R.; Airoldi, Claudio

    2010-01-01

    The compound N-[3-(trimethoxysilyl)propyl]diethylenetriamine (MPDET) was anchored onto Amazon kaolinite surface (KLT) by heterogeneous route. The modified and natural kaolinite clay samples were characterized by transmission electron microscopy (TEM), scanning electron microscopic (SEM), N 2 adsorption, powder X-ray diffraction, thermal analysis, ion exchange capacities, and nuclear magnetic nuclei of 29 Si and 13 C. The well-defined peaks obtained in the 13 C NMR spectrum in the 5.0-62.1 ppm region confirmed the attachment of organic functional groups as pendant chains bonded into the porous clay. The adsorption of uranyl on natural (KLT) and modified (KLT MPDET ) kaolinite clays was investigated as a function of the solution pH, metal concentration, temperature, and ionic strength. The ability of these materials to remove U(VI) from aqueous solution was followed by a series of adsorption isotherms adjusted to a Sips equation at room temperature and pH 4.0. The maximum number of moles adsorbed was determined to be 8.37 x 10 -3 and 13.87 x 10 -3 mmol g -1 for KLT and KLT MPDET at 298 K, respectively. The energetic effects (Δ int H, Δ int G, and Δ int S) caused by metal cations adsorption were determined through calorimetric titrations.

  8. Spectroscopic studies of U(VI) sorption at the kaolinite-water interface. Final report

    International Nuclear Information System (INIS)

    Thompson, H.A.; Parks, G.A.; Brown, G.E. Jr.

    1994-01-01

    Efficient use of U as a resource and safe handling, recycling and disposal of U-containing wastes require an understanding of the factors controlling the fate of U, where fate refers to the destination of U, typically expressed as an environmental medium or a process phase. The sorption process constitutes a change in elemental fate. Partitioning of an element from solution to a solid phase, or sorption, can be divided into three broad categories: adsorption, surface precipitation, and absorption. Extended X-ray absorption fine structure (EXAFS), a type of X-ray absorption spectroscopy (XAS), offers the possibility for distinguishing among different modes of sorption by characterizing the atomic environment of the sorbing element. In this study, the authors use EXAFS to determine the structure of U(VI) sorption complexes at the kaolinite-water interface. In Chapter One, they present an overview of selected aspects of U structural chemistry as a basis for considering the structural environment of U at the solid-water interface. To evaluate the utility of XAS for characterization of the structural environment of U(VI) at the solid-water interface, they have carried out an in-depth analysis of XAS data from U(VI)-containing solid and solution model compounds, which they describe in Chapter Two. In Chapter three, they consider sorption of U by kaolinite as a means of effecting the removal of U from surface collection pond waters on the Rocky Flats Plant site in northern Colorado

  9. impact of the use of electronic resources on research output

    African Journals Online (AJOL)

    manda

    ... Julita Nawe. University of Dar Es Salaam Library, P.O. Box 35092, Dar Es Salaam, Tanzania .... significantly, while 28.3% observed that quality of service to the community had improved .... resources and evaluate them is an important area.

  10. Salinity dependence of 226Ra adsorption on montmorillonite and kaolinite

    International Nuclear Information System (INIS)

    Shuji Tamamura; Takahiro Takada; Seiya Nagao; Masayoshi Yamamoto; Keisuke Fukushi

    2014-01-01

    The effect of NaCl concentration (10.0-1,000 mM) on 226 Ra adsorption was investigated in the presence of montmorillonite and kaolinite. A positive correlation was observed between the dissolved 226 Ra and NaCl concentrations in the presence of these adsorbents. Distribution coefficients decreased from the order of 10 4 to 10 0 (mL g -1 ) with an increase in NaCl concentration. Although the coefficients were higher for montmorillonite than kaolinite at lower NaCl concentrations, the trend was reversed at higher NaCl concentrations (≥500 mM) owing to the sharper reduction of the coefficient for montmorillonite with the increase in NaCl concentration. The rapid reduction was ascribed to higher negative charge density of montmorillonite, which leads the Ra 2+ adsorption mechanism to approach charge-compensating ion exchange. (author)

  11. Flocculation kinetics of kaolinite : role of aqueous phase species

    Energy Technology Data Exchange (ETDEWEB)

    House, P.; Wang, C.; Dhadli, N. [Shell Canada Ltd., Calgary, AB (Canada)

    2010-07-01

    Flocculation kinetics were used to study the rate-based processes that lead to aggregate growth and breakage of kaolinite in oil sands tailings. The role of aqueous phase species on aggregate growth, breakage and flocculant de-activation was studied. Collision efficiency and deactivation parameters were presented. The study showed that collisions can be efficient when the adsorption of the polymer is thermodynamically favorable. Up to 94 percent of adsorption takes place at the kaolinite edge. Studies have shown that hydrogen bonding sites on the kaolinite disappear with increases in pH values. The impact of molecular level interactions on flocculation kinetics were assessed in order to determine collision efficiencies and aggregate breakage rates. A focused beam reflectance model was used to monitor flocculation kinetics in situ. The period over which reflectance was observed was coupled with the laser velocity to determine the chord length of the particle. The kinetics of flocculation were observed for a 10 minute period. The effects of pH, calcium additions, and EDTA chelating agent additions were investigated. The study showed that calcium additions accelerate the rate of flocculant growth dramatically, and provide a much higher collision efficiency. Flocculants formed in the presence of calcium were weaker. The presence of salts promoted polymer adsorption by non-specific Van der Waals forces. tabs., figs.

  12. Preservation of and Permanent Access to Electronic Information Resources

    National Research Council Canada - National Science Library

    Hodge, Gail

    2004-01-01

    The rapid growth in the creation and dissemination of electronic information has emphasized the digital environment's speed and ease of dissemination with little regard for its long-term preservation and access...

  13. Electronic conferencing for continuing medical education: a resource survey.

    Science.gov (United States)

    Sternberg, R J

    1986-10-01

    The use of electronic technologies to link participants for education conferences is an option for providers of Continuing Medical Education. In order to profile the kinds of electronic networks currently offering audio- or videoteleconferences for physician audiences, a survey was done during late 1985. The information collected included range of services, fees, and geographic areas served. The results show a broad diversity of providers providing both interactive and didactic programming to both physicians and other health care professionals.

  14. Controlling user access to electronic resources without password

    Science.gov (United States)

    Smith, Fred Hewitt

    2017-08-22

    Described herein are devices and techniques for remotely controlling user access to a restricted computer resource. The process includes obtaining an image from a communication device of a user. An individual and a landmark are identified within the image. Determinations are made that the individual is the user and that the landmark is a predetermined landmark. Access to a restricted computing resource is granted based on the determining that the individual is the user and that the landmark is the predetermined landmark. Other embodiments are disclosed.

  15. New kaolinite phases expanded through intercalation with potassium acetate

    International Nuclear Information System (INIS)

    Frost, R.L.; Kristof, J.; Kloprogge, J.T.

    1998-01-01

    Full text: Changes in the hydroxyl surfaces of potassium acetate-intercalated kaolinite have been studied over the ambient to predehydroxylation temperature range using a combination of X-ray diffraction and Raman spectroscopy. Upon intercalation, the kaolinite expanded along the c-axis direction to 13.88 Angstroms. Upon heating the intercalation complex over the 50 to 300 deg C range, X-ray diffraction shows the existence of three additional intercalation phases with d-spacings of 9.09, 9.60, and 11.47 Angstroms. The amount of each phase is temperature dependent. These expansions are reversible and upon cooling the intercalation complex returned to its original spacing. The 13.88 Angstroms phase only existed in the presence of water. It is proposed that the expanded kaolinite intercalation phases result from the orientation of the acetate within the intercalation complex. The Raman spectra of the hydroxyl-stretching region (Frost and van der Gaast, 1997) of potassium acetate-intercalated kaolinite has been obtained under an atmosphere of both air and nitrogen using a thermal stage over the 25 to 300 deg C temperature range (Johansson et al., 1998). Raman spectra of the C-C, C=O stretching and O-C-O bending modes show that at least two types of acetate are present in the intercalation complex. These are assigned to two different orientations of the acetate. At 25 deg C, a new band at 3606 cm -1 attributed to the inner surface hydroxyl hydrogen bonded to the acetate ion is observed with a concomitant loss of intensity in the bands attributed to the inner surface hydroxyls (Frost and Kristof, 1997, Frost et al.,1997). Heating the intercalation complex to 50 deg C results in two hydroxyl-stretching frequencies at 3594 and 3604 cm -1 . This change in frequencies is ascribed to phase changes of the potassium acetate-intercalated kaolinite. At 100 deg C, the bands shift to 3600 and 3613 cm -1 . These shifts in frequencies are assigned to new kaolinite expanded phases. At

  16. Electron beam pasteurised oil palm waste: a potential feed resource

    International Nuclear Information System (INIS)

    Mat Rasol Awang; Hassan Hamdani Mutaat; Tamikazu Kume; Tachibana, H.

    2002-01-01

    Pasteurization of oil palm empty fruit bunch (EFB) was performed using electron beam single sided irradiation. The dose profiles of oil palm EFB samples for different thickness in both directions X and Y were established. The results showed the usual characteristics dose uniformity as sample thickness decreased. The mean average absorbed dose on both sides at the surface and bottom of the samples for different thickness samples lead to establishing depth dose curve. Based on depth dose curve and operation conditions of electron beam machine, the process throughput for pasteurized oil palm EFB were estimated. (Author)

  17. Kaolinite and Silica Dispersions in Low-Salinity Environments: Impact on a Water-in-Crude Oil Emulsion Stability

    Directory of Open Access Journals (Sweden)

    Vladimir Alvarado

    2011-10-01

    Full Text Available This research aims at providing evidence of particle suspension contributions to emulsion stability, which has been cited as a contributing factor in crude oil recovery by low-salinity waterflooding. Kaolinite and silica particle dispersions were characterized as functions of brine salinity. A reference aqueous phase, representing reservoir brine, was used and then diluted with distilled water to obtain brines at 10 and 100 times lower Total Dissolved Solid (TDS. Scanning Electron Microscope (SEM and X-ray Diffraction (XRD were used to examine at the morphology and composition of clays. The zeta potential and particle size distribution were also measured. Emulsions were prepared by mixing a crude oil with brine, with and without dispersed particles to investigate emulsion stability. The clay zeta potential as a function of pH was used to investigate the effect of particle charge on emulsion stability. The stability was determined through bottle tests and optical microscopy. Results show that both kaolinite and silica promote emulsion stability. Also, kaolinite, roughly 1 mm in size, stabilizes emulsions better than larger clay particles. Silica particles of larger size (5 µm yielded more stable emulsions than smaller silica particles do. Test results show that clay particles with zero point of charge (ZPC at low pH become less effective at stabilizing emulsions, while silica stabilizes emulsions better at ZPC. These result shed light on emulsion stabilization in low-salinity waterflooding.

  18. Availability of Electronic Resources for Service Provision in ...

    African Journals Online (AJOL)

    The study also revealed that majority of the University libraries have adequate basic infrastructure for effective electronic information services. ... acquired by the library are put into maximal use by the library clientele, thereby ensuring the achievement of the library's objective which is satisfying the users, information needs.

  19. Utilization of bio-resources by low energy electron beam

    International Nuclear Information System (INIS)

    Kume, Tamikazu

    2003-01-01

    Utilization of bio-resources by radiation has been investigated for recycling the natural resources and reducing the environmental pollution. Polysaccharides such as chitosan and sodium alginate were easily degraded by irradiation and induced various kinds of biological activities, i.g. anti-microbial activity, promotion of plant growth, suppression of heavy metal stress, phytoalexins induction. Radiation degraded chitosan was effective to enhance the growth of plants in tissue culture. It was demonstrated that the liquid sample irradiation system using low energy EB was effective for the preparation of degraded polysaccharides. Methylcellulose (MC) can be crosslinked under certain radiation condition as same as carboxymethylcellulose (CMC) and produced the biodegradable hydrogel for medical and agricultural use. Treatment of soybean seeds by low energy EB enhanced the growth and the number of rhizobia on the root. (author)

  20. Analysis of Pedagogic Potential of Electronic Educational Resources with Elements of Autodidactics

    Directory of Open Access Journals (Sweden)

    Igor A.

    2018-03-01

    Full Text Available Introduction: in recent years didactic properties of electronic educational resources undergo considerable changes, nevertheless, the question of studying of such complete phenomenon as “an electronic educational resource with autodidactics elements” remains open, despite sufficient scientific base of researches of the terms making this concept. Article purpose – determination of essence of electronic educational resources with autodidactics elements. Materials and Methods: the main method of research was the theoretical analysis of the pedagogical and psychological literature on the problem under study. We used the theoretical (analysis, synthesis, comparison and generalization methods, the method of interpretation, pedagogical modeling, and empirical methods (observation, testing, conversation, interview, analysis of students’ performance, pedagogical experiment, peer review. Results: we detected the advantages of electronic educational resources in comparison with traditional ones. The concept of autodidactics as applied to the subject of research is considered. Properties of electronic educational resources with a linear and nonlinear principle of construction are studied.The influence of the principle of construction on the development of the learners’ qualities is shown. We formulated an integral definition of electronic educational resources with elements of autodidactics, namely, the variability, adaptivity and cyclicity of training. A model of the teaching-learning process with electronic educational resources is developed. Discussion and Conclusions: further development of a problem will allow to define whether electronic educational resources with autodidactics elements pedagogical potential for realization of educational and self-educational activity of teachers have, to modify technological procedures taking into account age features of students, their specialties and features of the organization of process of training of

  1. Effect of high-energy ball milling in the structural and textural properties of kaolinite

    Directory of Open Access Journals (Sweden)

    E. C. Leonel

    2014-06-01

    Full Text Available Through the process of high-energy ball milling it is possible to obtain solid materials with higher surface area and different particle sizes. These characteristics are very important for some application such as adsorption. Besides, applications of some clays depend on the functionalization which, for kaolinite, takes place in the aluminol groups. Modification in the structural and textural properties of kaolinite by high-energy milling can improve functionalization of kaolinite due to the exposure of aluminol groups. In this work studies were done on the influence of high-energy ball milling on the morphological properties of kaolinite, taking into account parameters such as filling of the miller, number of balls and amount of mass to be milled. Moreover, studies involving milling kinetics of purified kaolinite were carried out to verify modification in the morphology of kaolinite with milling time.

  2. Dating Amazonian laterites through the novel geochronometers kaolinite and iron oxides

    Science.gov (United States)

    Allard, Thierry; Bressan Riffel, Silvana; Gautheron, Cécile; Fernandes Soares, Bruna; Pinna-Jamme, Rosella; Morin, Guillaume

    2016-04-01

    Soils on Earth's surface are in constant interaction with climate. As a matter of fact, soils cannot only produce greenhouse effect gases, such as NO2 and CH4, but also behave as sinks for CO2, especially by silicate weathering. Major processes of silicate weathering are known and exhibit climatic zonation at the global scale. Laterites are particularly relevant because they are ancient and deeply weathered soils of major significance. They occupy 30 % of the continental surface and can keep records of past climates and landscape modifications (paleosurface) through specific mineral markers. These formations reach several tens of meters and are mainly composed of kaolinite, iron and aluminium oxides as well as relicts of parent minerals such as quartz and ancillary minerals. Once the major processes of laterite formation are known, their age will allow a growth of researches, owing to the implementation of various chronometers. Moreover, it is fundamental to date laterites in order to improve our understanding of soil formation related to paleoclimates, and to build predictive models of their evolution. In this study, we focus on comparing kaolinite ages with the still unknown ages of lateritic duricrusts from the central Amazon region (Brazil), where strong weathering processes were developed from the early Tertiary, after the Andean uplift. The central Amazon region displays flat areas and dissected plateaus (100-180 m a.s.l.) sustained by weathered clastic sedimentary rocks and latosols. The region contains horizons of duricrusts, relatively continuous layers of Fe-cuirasses, stratified lateritic profiles, and kaolin deposits. Here we employed two methods to date ubiquitous secondary minerals of laterite, which are consistent with geological time-scale. The corresponding geochronometers are the following: (i) radiation-induced defects in kaolinite (trapped in duricrusts) analysed by electron paramagnetic resonance spectroscopy (EPR) (Balan et al., 2005), and (ii

  3. A Study on Developing Evaluation Criteria for Electronic Resources in Evaluation Indicators of Libraries

    Science.gov (United States)

    Noh, Younghee

    2010-01-01

    This study aimed to improve the current state of electronic resource evaluation in libraries. While the use of Web DB, e-book, e-journal, and other e-resources such as CD-ROM, DVD, and micro materials is increasing in libraries, their use is not comprehensively factored into the general evaluation of libraries and may diminish the reliability of…

  4. Managing Selection for Electronic Resources: Kent State University Develops a New System to Automate Selection

    Science.gov (United States)

    Downey, Kay

    2012-01-01

    Kent State University has developed a centralized system that manages the communication and work related to the review and selection of commercially available electronic resources. It is an automated system that tracks the review process, provides selectors with price and trial information, and compiles reviewers' feedback about the resource. It…

  5. Where Do Electronic Books Fit in the College Research Arsenal of Resources?

    Science.gov (United States)

    Barbier, Patricia

    2007-01-01

    Student use of electronic books has become an accepted supplement to traditional resources. Student use and satisfaction was monitored through an online course discussion board. Increased use of electronic books indicate this service is an accepted supplement to the print book collection.

  6. Theoretical study of heavy metal Cd, Cu, Hg, and Ni(II) adsorption on the kaolinite(0 0 1) surface

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Jian, E-mail: zhaojian0209@aliyun.com [Institute of Applied Physics and Computational Mathematics, PO Box 8009, Beijing 100088 (China); State Key Laboratory of Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Beijing 100083 (China); He, Man-Chao [State Key Laboratory of Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Beijing 100083 (China)

    2014-10-30

    Highlights: • We investigated the adsorption of Cd, Cu, Hg, and Ni(II) on kaolinite(0 0 1) surface. • The adsorption capabilities of the kaolinite for HM atoms were Ni > Cu > Cd > Hg(II). • The adsorption energy increases with the coverage for Cd, Cu, and Hg(II) atoms. • The adsorption energy decreases with the coverage for Ni(II) atoms. - Abstract: Heavy metal pollution is currently of great concern because it has been recognized as a potential threat to air, water, and soil. Adsorption was one of the most popular methods for the removal of heavy metal. The adsorption of heavy metal Cd, Cu, Hg, and Ni(II) atoms on the hydroxylated (0 0 1) surface of kaolinite was investigated using density-functional theory within the generalized gradient approximation and a supercell approach. The coverage dependence of the adsorption structures and energetics were systematically studied for a wide range of coverage Θ [from 0.11 to 1.0 monolayers (ML)] and adsorption sites. The most stable among all possible adsorption sites for Cd(II) atom was the two-fold bridge site followed by the one-fold top site, and the top site was the most favorite adsorption site for Cu and Ni(II) atoms, while the three-fold hollow site was the most stable adsorption site for Hg(II) atom followed by the two-fold bridge site. The adsorption energy increases with the coverage for Cd, Cu, and Hg(II) atoms, thus indicating the higher stability of surface adsorption and a tendency to the formation of adsorbate islands (clusters) with increasing the coverage. However, the adsorption energy of Ni(II) atoms decreases when increasing the coverage. The adsorption capabilities of the kaolinite clay for the heavy metal atoms were in the order of Ni > Cu > Cd > Hg(II). The other properties of the Cd, Cu, Hg, and Ni(II)/kaolinite(0 0 1) system including the different charge distribution, the lattice relaxation, and the electronic density of states were also studied and discussed in detail.

  7. Theoretical study of heavy metal Cd, Cu, Hg, and Ni(II) adsorption on the kaolinite(0 0 1) surface

    International Nuclear Information System (INIS)

    Zhao, Jian; He, Man-Chao

    2014-01-01

    Highlights: • We investigated the adsorption of Cd, Cu, Hg, and Ni(II) on kaolinite(0 0 1) surface. • The adsorption capabilities of the kaolinite for HM atoms were Ni > Cu > Cd > Hg(II). • The adsorption energy increases with the coverage for Cd, Cu, and Hg(II) atoms. • The adsorption energy decreases with the coverage for Ni(II) atoms. - Abstract: Heavy metal pollution is currently of great concern because it has been recognized as a potential threat to air, water, and soil. Adsorption was one of the most popular methods for the removal of heavy metal. The adsorption of heavy metal Cd, Cu, Hg, and Ni(II) atoms on the hydroxylated (0 0 1) surface of kaolinite was investigated using density-functional theory within the generalized gradient approximation and a supercell approach. The coverage dependence of the adsorption structures and energetics were systematically studied for a wide range of coverage Θ [from 0.11 to 1.0 monolayers (ML)] and adsorption sites. The most stable among all possible adsorption sites for Cd(II) atom was the two-fold bridge site followed by the one-fold top site, and the top site was the most favorite adsorption site for Cu and Ni(II) atoms, while the three-fold hollow site was the most stable adsorption site for Hg(II) atom followed by the two-fold bridge site. The adsorption energy increases with the coverage for Cd, Cu, and Hg(II) atoms, thus indicating the higher stability of surface adsorption and a tendency to the formation of adsorbate islands (clusters) with increasing the coverage. However, the adsorption energy of Ni(II) atoms decreases when increasing the coverage. The adsorption capabilities of the kaolinite clay for the heavy metal atoms were in the order of Ni > Cu > Cd > Hg(II). The other properties of the Cd, Cu, Hg, and Ni(II)/kaolinite(0 0 1) system including the different charge distribution, the lattice relaxation, and the electronic density of states were also studied and discussed in detail

  8. Combined experimental and theoretical investigation of interactions between kaolinite inner surface and intercalated dimethyl sulfoxide

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Shuai [School of Geoscience and Surveying Engineering, China University of Mining & Technology, Beijing 100083 (China); Liu, Qinfu, E-mail: lqf@cumtb.edu.cn [School of Geoscience and Surveying Engineering, China University of Mining & Technology, Beijing 100083 (China); Cheng, Hongfei [School of Geoscience and Surveying Engineering, China University of Mining & Technology, Beijing 100083 (China); Zeng, Fangui [Department of Earth Science and Engineering, Taiyuan University of Technology, Taiyuan 030024 (China)

    2015-03-15

    Graphical abstract: Snapshot of the kaolinite–DMSO system after equilibrium is reached. - Highlights: • Dimethyl sulfoxide arranges a monolayer structure between kaolinite layers. • Weak hydrogen bonds exist between methyl groups of dimethyl sulfoxide and kaolinite silica layer. • Intercalated dimethyl sulfoxide forms strong hydrogen bonds with kaolinite alumina layer. - Abstract: Kaolinite intercalation complex with dimethyl sulfoxide (DMSO) was investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetry–differential scanning calorimetry (TG–DSC) combined with molecular dynamics simulation. The bands assigned to the OH stretching of inner surface of kaolinite were significantly perturbed after intercalation of DMSO into kaolinite. Additionally, the bands attributed to the vibration of gibbsite-like layers of kaolinite shifted to the lower wave number, indicating that the intercalated DMSO were strongly hydrogen bonded to the alumina octahedral surface of kaolinite. The slightly decreased intensity of 1031 cm{sup −1} and 1016 cm{sup −1} band due to the in-plane vibration of Si−O of kaolinite revealed that some DMSO molecules formed weak hydrogen bonds with the silicon tetrahedral surface of kaolinite. Based on the TG result of kaolinite–DMSO intercalation complex, the formula of A1{sub 2}Si{sub 2}O{sub 5}(OH){sub 4}(DMSO){sub 0.7} was obtained, with which the kaolinite–DMSO complex model was constructed. The molecular dynamics simulation of kaolinite–DMSO complex directly confirmed the monolayer structure of DMSO in interlayer space of kaolinite, where the DMSO arranged almost parallel with kaolinite basal surface with all methyl groups being distributed near the interlayer midplane and oxygen atoms orienting toward to the alumina octahedral surface. The radial distribution function between kaolinite and intercalated DMSO verified the strong hydrogen bonds forming between hydroxyl hydrogen

  9. {alpha}-Pinene conversion by modified-kaolinitic clay

    Energy Technology Data Exchange (ETDEWEB)

    Volzone, C. [CETMIC-Centro de Tecnologia de Recursos Minerales y Ceramica-(CONICET-CIC), C.C. 49, Cno. Centenario y 506 (1897) M.B. Gonnet, Prov., Buenos Aires (Argentina)]. E-mail: volzcris@netverk.com.ar; Masini, O. [INTEQUI (CONICET-UNSL), Facultad de Ingenieria y Ciencias Economico Sociales, 25 de Mayo 384, V. Mercedes, Prov., San Luis (Argentina); Comelli, N.A. [INTEQUI (CONICET-UNSL), Facultad de Ingenieria y Ciencias Economico Sociales, 25 de Mayo 384, V. Mercedes, Prov., San Luis (Argentina); Grzona, L.M. [INTEQUI (CONICET-UNSL), Facultad de Ingenieria y Ciencias Economico Sociales, 25 de Mayo 384, V. Mercedes, Prov., San Luis (Argentina); Ponzi, E.N. [CINDECA (CONICET-UNLP) calle 47 No. 257 (1900) La Plata, Prov., Buenos Aires (Argentina); Ponzi, M.I. [INTEQUI (CONICET-UNSL), Facultad de Ingenieria y Ciencias Economico Sociales, 25 de Mayo 384, V. Mercedes, Prov., San Luis (Argentina)

    2005-10-15

    The isomerization of {alpha}-pinene using natural kaolinitic clay before and after different treatments was studied in this work. The kaolinite is a clay material constituted by phyllosilicate 1:1 layer (one sheet of tetrahedral silicon and one sheet of octahedral alumina). The clay was treated at different times using 6.0 N solution of sulfuric acid previous heating to 500 or 700 K. The materials were characterized by X-ray diffraction, by chemical analyses and acidity measurements. The catalytic reactions were carried out at 373 K in a reactor batch with condenser and stirrer. Samples were taken at regular intervals, and reactants and products were quantitatively analyzed with a gas chromatograph after separation of the individual compounds. Conversions of alpha pinene between 67 and 94%, and selectivities in camphene and in limonene of 65 and 23%, respectively, were obtained with the clay treated at different conditions. The structural and textural changes of the clay by the treatments influenced on catalytic reactions.

  10. Hydrometallurgical extraction of Al and Si from kaolinitic clays

    Directory of Open Access Journals (Sweden)

    Eliana G. Pinna

    Full Text Available Abstract Herein is presented the results of a study on the hydrometallurgic extraction and recovery of aluminum and silicon by leaching of kaolinitic clays with HF. The studied extraction parameters were: temperature, reaction time, solid/liquid ratio, concentration, and precipitating agent mass. In the leaching process, mineral dissolutions near 100% were obtained when working at 348 K, solid/liquid ratio 2% w/v, HF 12% v/v, for 120 minutes. The HF leach liquor generated from the dissolution of kaolinitic clays contains H2SiF6and H3AlF6. Studies were conducted to recover the two valuable fluorides as K2SiF6and Na3AlF6by precipitation with alkaline salts from the leach liquor. Phases of precipitated fluorides were identified by XRD and surface morphology by SEM. The purity of the K2SiF6precipitate was 98.8%, whereas for Na3AlF6, it was 89.3%. Also, both synthesized solids are of high commercial value due to their industrial applications.

  11. Intensified Pozzolanic Reaction on Kaolinite Clay-Based Mortar

    Directory of Open Access Journals (Sweden)

    Yang-Hee Kwon

    2017-05-01

    Full Text Available The objective of this study is to develop and characterize kaolinite clay-based structural mortar. The pozzolanic reaction induced from two mineral additives, i.e., calcium hydroxide and silica fume (SF, and the physical filling effect from SF, were found to be effective on the enhancement of structural properties. Based on several preliminary experiments, 7:3 ratio of kaolinite clay/calcium hydroxide was selected as a basic binder. Then, the amount of SF was chosen as 0%, 7.5%, and 15% of the total binder to consider both the chemical and physical effects. The results showed that compressive strengths of samples with 7.5% and 15% SF are significantly increased by approximately 200% and 350%, respectively, at 28 days compared to the sample without SF. However, based on the results of the sample with 15% SF, it is found that excessive addition of SF causes long-term strength loss, possibly owing to micro cracks. With the careful consideration on this long-term behavior, this suggested new mix design can be further extended to develop sustainable structural materials using natural minerals or waste materials with nonbinding properties.

  12. α-Pinene conversion by modified-kaolinitic clay

    International Nuclear Information System (INIS)

    Volzone, C.; Masini, O.; Comelli, N.A.; Grzona, L.M.; Ponzi, E.N.; Ponzi, M.I.

    2005-01-01

    The isomerization of α-pinene using natural kaolinitic clay before and after different treatments was studied in this work. The kaolinite is a clay material constituted by phyllosilicate 1:1 layer (one sheet of tetrahedral silicon and one sheet of octahedral alumina). The clay was treated at different times using 6.0 N solution of sulfuric acid previous heating to 500 or 700 K. The materials were characterized by X-ray diffraction, by chemical analyses and acidity measurements. The catalytic reactions were carried out at 373 K in a reactor batch with condenser and stirrer. Samples were taken at regular intervals, and reactants and products were quantitatively analyzed with a gas chromatograph after separation of the individual compounds. Conversions of alpha pinene between 67 and 94%, and selectivities in camphene and in limonene of 65 and 23%, respectively, were obtained with the clay treated at different conditions. The structural and textural changes of the clay by the treatments influenced on catalytic reactions

  13. The National Site Licensing of Electronic Resources: An Institutional Perspective

    Directory of Open Access Journals (Sweden)

    Xiaohua Zhu

    2011-06-01

    Full Text Available While academic libraries in most countries are struggling to negotiate with publishers and vendors individually or collaboratively via consortia, a few countries have experimented with a different model, national site licensing (NSL. Because NSL often involves government and large-scale collaboration, it has the potential to solve many problems in the complex licensing world. However, not many nations have adopted it. This study uses historical research approach and the comparative case study research method to explore the seemingly low level of adoption. The cases include the Canadian National Site Licensing Project (CNSLP, the United Kingdom’s National Electronic Site Licensing Initiative (NESLI, and the United States, which has not adopted NSL. The theoretical framework guiding the research design and data collection is W. Richard Scott’s institutional theory, which utilizes three supporting pillars—regulative, normative, and cultural-cognitive—to analyze institutional processes. In this study, the regulative pillar and the normative pillar of NSL adoption— an institutional construction and change—are examined. Data were collected from monographs, research articles, government documents, and relevant websites. Based on the analysis of these cases, a preliminary model is proposed for the adoption of NSL. The factors that support a country’s adoption of NSL include the need for new institutions, a centralized educational policy-making system and funding system, supportive political trends, and the tradition of cooperation. The factors that may prevent a country from adopting NSL include decentralized educational policy and funding, diversity and the large number of institutions, the concern for the “Big Deal,” and the concern for monopoly.

  14. Uranium (VI) transport in saturated heterogeneous media: Influence of kaolinite and humic acid.

    Science.gov (United States)

    Chen, Chong; Zhao, Kang; Shang, Jianying; Liu, Chongxuan; Wang, Jin; Yan, Zhifeng; Liu, Kesi; Wu, Wenliang

    2018-05-07

    Natural aquifers typically exhibit a variety of structural heterogeneities. However, the effect of mineral colloids and natural organic matter on the transport behavior of uranium (U) in saturated heterogeneous media are not totally understood. In this study, heterogeneous column experiments were conducted, and the constructed columns contained a fast-flow domain (FFD) and a slow-flow domain (SFD). The effect of kaolinite, humic acid (HA), and kaolinite/HA mixture on U(VI) retention and release in saturated heterogeneous media was examined. Media heterogeneity significantly influenced U fate and transport behavior in saturated subsurface environment. The presence of kaolinite, HA, and kaolinite/HA enhanced the mobility of U in heterogeneous media, and the mobility of U was the highest in the presence of kaolinite/HA and the lowest in the presence of kaolinite. In the presence of kaolinite, there was no difference in the amount of U released from the FFD and SFD. However, in the presence of HA and kaolinite/HA, a higher amount of U was released from the FFD. The findings in this study showed that medium structure and mineral colloids, as well as natural organic matter in the aqueous phase had significant effects on U transport and fate in subsurface environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Formation and Transformation of Iron Oxide-Kaolinite Associations in the Presence of Iron(II)

    NARCIS (Netherlands)

    Wei, S.Y.; Liu, F.; Feng, X.H.; Tan, W.F.; Koopal, L.K.

    2011-01-01

    Iron oxide-kaolinite associations are important components of tropical and subtropical soils and have significant influence on the physical and chemical properties of soils. In this study, the formation and transformation of Fe oxide-kaolinite associations as a function of pH, temperature, and time

  16. Estimation of silver in Ag-meta kaolinite by neutron activation

    International Nuclear Information System (INIS)

    Daniels, E.A.; Rao, S.M.

    1981-01-01

    The present work is based on the neutron activation of Ag-meta kaolinite for the determination of its silver content from the β-activity of the compound using standard tables which showed the percentage of silver in mixtures of silver nitrate and meta kaolinite of known composition against β-activity of the mixture activated under identical conditions. (author)

  17. A survey of the use of electronic scientific information resources among medical and dental students

    Directory of Open Access Journals (Sweden)

    Aarnio Matti

    2006-05-01

    Full Text Available Abstract Background To evaluate medical and dental students' utilization of electronic information resources. Methods A web survey sent to 837 students (49.9% responded. Results Twenty-four per cent of medical students and ninteen per cent of dental students searched MEDLINE 2+ times/month for study purposes, and thiry-two per cent and twenty-four per cent respectively for research. Full-text articles were used 2+ times/month by thirty-three per cent of medical and ten per cent of dental students. Twelve per cent of respondents never utilized either MEDLINE or full-text articles. In multivariate models, the information-searching skills among students were significantly associated with use of MEDLINE and full-text articles. Conclusion Use of electronic resources differs among students. Forty percent were non-users of full-text articles. Information-searching skills are correlated with the use of electronic resources, but the level of basic PC skills plays not a major role in using these resources. The student data shows that adequate training in information-searching skills will increase the use of electronic information resources.

  18. Analytical Study of Usage of Electronic Information Resources at Pharmacopoeial Libraries in India

    Directory of Open Access Journals (Sweden)

    Sunil Tyagi

    2014-02-01

    Full Text Available The objective of this study is to know the rate and purpose of the use of e-resource by the scientists at pharmacopoeial libraries in India. Among other things, this study examined the preferences of the scientists toward printed books and journals, electronic information resources, and pattern of using e-resources. Non-probability sampling specially accidental and purposive technique was applied in the collection of primary data through administration of user questionnaire. The sample respondents chosen for the study consists of principle scientific officer, senior scientific officer, scientific officer, and scientific assistant of different division of the laboratories, namely, research and development, pharmaceutical chemistry, pharmacovigilance, pharmacology, pharmacogonosy, and microbiology. The findings of the study reveal the personal experiences and perceptions they have had on practice and research activity using e-resource. The major findings indicate that of the total anticipated participants, 78% indicated that they perceived the ability to use computer for electronic information resources. The data analysis shows that all the scientists belonging to the pharmacopoeial libraries used electronic information resources to address issues relating to drug indexes and compendia, monographs, drugs obtained through online databases, e-journals, and the Internet sources—especially polices by regulatory agencies, contacts, drug promotional literature, and standards.

  19. Considering Point-of-Care Electronic Medical Resources in Lieu of Traditional Textbooks for Medical Education.

    Science.gov (United States)

    Hale, LaDonna S; Wallace, Michelle M; Adams, Courtney R; Kaufman, Michelle L; Snyder, Courtney L

    2015-09-01

    Selecting resources to support didactic courses is a critical decision, and the advantages and disadvantages must be carefully considered. During clinical rotations, students not only need to possess strong background knowledge but also are expected to be proficient with the same evidence-based POC resources used by clinicians. Students place high value on “real world” learning and therefore may place more value on POC resources that they know practicing clinicians use as compared with medical textbooks. The condensed nature of PA education requires students to develop background knowledge and information literacy skills over a short period. One way to build that knowledge and those skills simultaneously is to use POC resources in lieu of traditional medical textbooks during didactic training. Electronic POC resources offer several advantages over traditional textbooks and should be considered as viable options in PA education.

  20. Elektronik Bilgi Kaynaklarının Seçimi / Selection of Electronic Information Resources

    Directory of Open Access Journals (Sweden)

    Pınar Al

    2003-04-01

    Full Text Available For many years, library users have used only from the printed media in order to get the information that they have needed. Today with the widespread use of the Web and the addition of electronic information resources to library collections, the use of information in the electronic environment as well as in printed media is started to be used. In time, such types of information resources as, electronic journals, electronic books, electronic encyclopedias, electronic dictionaries and electronic theses have been added to library collections. In this study, selection criteria that can be used for electronic information resources are discussed and suggestions are provided for libraries that try to select electronic information resources for their collections.

  1. Acidity of edge surface sites of montmorillonite and kaolinite

    Science.gov (United States)

    Liu, Xiandong; Lu, Xiancai; Sprik, Michiel; Cheng, Jun; Meijer, Evert Jan; Wang, Rucheng

    2013-09-01

    Acid-base chemistry of clay minerals is central to their interfacial properties, but up to now a quantitative understanding on the surface acidity is still lacking. In this study, with first principles molecular dynamics (FPMD) based vertical energy gap technique, we calculate the acidity constants of surface groups on (0 1 0)-type edges of montmorillonite and kaolinite, which are representatives of 2:1 and 1:1-type clay minerals, respectively. It shows that tbnd Si-OH and tbnd Al-OH2OH groups of kaolinite have pKas of 6.9 and 5.7 and those of montmorillonite have pKas of 7.0 and 8.3, respectively. For each mineral, the calculated pKas are consistent with the experimental ranges derived from fittings of titration curves, indicating that tbnd Si-OH and tbnd Al-OH2OH groups are the major acidic sites responsible to pH-dependent experimental observations. The effect of Mg substitution in montmorillonite is investigated and it is found that Mg substitution increases the pKas of the neighboring tbnd Si-OH and tbnd Si-OH2 groups by 2-3 pKa units. Furthermore, our calculation shows that the pKa of edge tbnd Mg-(OH2)2 is as high as 13.2, indicating the protonated state dominates under common pH. Together with previous adsorption experiments, our derived acidity constants suggest that tbnd Si-O- and tbnd Al-(OH)2 groups are the most probable edge sites for complexing heavy metal cations.

  2. Use of electronic sales data to tailor nutrition education resources for an ethnically diverse population.

    Science.gov (United States)

    Eyles, H; Rodgers, A; Ni Mhurchu, C

    2010-02-01

    Nutrition education may be most effective when personally tailored. Individualised electronic supermarket sales data offer opportunities to tailor nutrition education using shopper's usual food purchases. The present study aimed to use individualised electronic supermarket sales data to tailor nutrition resources for an ethnically diverse population in a large supermarket intervention trial in New Zealand. Culturally appropriate nutrition education resources (i.e. messages and shopping lists) were developed with the target population (through two sets of focus groups) and ethnic researchers. A nutrient database of supermarket products was developed using retrospective sales data and linked to participant sales to allow tailoring by usual food purchases. Modified Heart Foundation Tick criteria were used to identify 'healthier' products in the database suitable for promotion in the resources. Rules were developed to create a monthly report listing the tailored and culturally targeted messages to be sent to each participant, and to produce automated, tailored shopping lists. Culturally targeted nutrition messages (n = 864) and shopping lists (n = 3 formats) were developed. The food and nutrient database (n = 3000 top-selling products) was created using 12 months of retrospective sales data, and comprised 60%'healthier' products. Three months of baseline sales data were used to determine usual food purchases. Tailored resources were successfully mailed to 123 Māori, 52 Pacific and 346 non-Māori non-Pacific participants over the 6-month trial intervention period. Electronic supermarket sales data can be used to tailor nutrition education resources for a large number of ethnically diverse supermarket shoppers.

  3. REVIEW OF MOODLE PLUGINS FOR DESIGNING MULTIMEDIA ELECTRONIC EDUCATIONAL RESOURCES FROM LANGUAGE DISCIPLINES

    Directory of Open Access Journals (Sweden)

    Anton M. Avramchuk

    2015-09-01

    Full Text Available Today the problem of designing multimedia electronic educational resources from language disciplines in Moodle is very important. This system has a lot of different, powerful resources, plugins to facilitate the learning of students with language disciplines. This article presents an overview and comparative analysis of the five Moodle plugins for designing multimedia electronic educational resources from language disciplines. There have been considered their key features and functionality in order to choose the best for studying language disciplines in the Moodle. Plugins are compared by a group of experts according to the criteria: efficiency, functionality and easy use. For a comparative analysis of the plugins it is used the analytic hierarchy process.

  4. Optimization of uranyl ions removal from aqueous solution by natural and modified kaolinites

    Energy Technology Data Exchange (ETDEWEB)

    Elhefnawy, O.A.; Elabd, A.A. [Nuclear and Radiological Regulatory Authority (NRRA), Cairo (Egypt). Nuclear Safeguards and Physical Protection Dept.

    2017-10-01

    The paper addresses the modifications of the most common mineral clay ''kaolinite'' for U(VI) removal from aqueous solutions. A new modified Egyptian natural kaolinite (Ca-MK) was prepared by coating kaolinite with calcium oxide. Another modification process was utilized by calcination and acid activation of kaolinite (E-MK). The Egyptian natural kaolinite (E-NK) and the two modified kaolinites were characterized by different techniques SEM, EDX, XRD, and FTIR. The removal process were investigated in batch experiments as a function of pH, contact time, initial U(VI) concentration, effect of temperature, and recovery of U(VI) were studied. The equilibrium stage was achieved after 60 min and the kinetic data was described well by pseudo-second order model. Isothermal data was better described by the Langmuir isotherm model, indicating the homogeneous removal process. Also the removal process was studied on different temperature 293, 313, and 323 K. The thermodynamic parameters ΔH , ΔS , and ΔG were calculated. The thermodynamic results pointed to the endothermic and favorable nature of the U(VI) removal process in the three kaolinite adsorbents. This study indicated that (Ca-MK) has higher CEC and can be used as a new adsorbent for highly efficient removal of U(VI) from aqueous solutions.

  5. Effects of the Use of Electronic Human Resource Management (EHRM Within Human Resource Management (HRM Functions at Universities

    Directory of Open Access Journals (Sweden)

    Chux Gervase Iwu

    2016-09-01

    Full Text Available This study set out to examine the effect of e-hrm systems in assisting human resource practitioners to execute their duties and responsibilities. In comparison to developed economies of the world, information technology adoption in sub-Saharan Africa has not been without certain glitches. Some of the factors that are responsible for these include poor need identification, sustainable funding, and insufficient skills. Besides these factors, there is also the issue of change management and users sticking to what they already know. Although, the above factors seem negative, there is strong evidence that information systems such as electronic human resource management present benefits to an organization. To achieve this, a dual research approach was utilized. Literature assisted immensely in both the development of the conceptual framework upon which the study hinged as well as in the development of the questionnaire items. The study also made use of an interview checklist to guide the participants. The findings reveal a mix of responses that indicate that while there are gains in adopting e-hrm systems, it is wiser to consider supporting resources as well as articulate the needs of the university better before any investment is made.

  6. Understanding the sorption mechanisms of aflatoxin B1 to kaolinite, illite, and smectite clays via a comparative computational study.

    Science.gov (United States)

    Kang, Fuxing; Ge, Yangyang; Hu, Xiaojie; Goikavi, Caspar; Waigi, Michael Gatheru; Gao, Yanzheng; Ling, Wanting

    2016-12-15

    In current adsorption studies of biotoxins to phyllosilicate clays, multiply weak bonding types regarding these adsorptions are not well known; the major attractive forces, especially for kaolinite and illite, are difficult to be identified as compared to smectite with exchangeable cations. Here, we discriminated the bonding types of aflatoxin B1 (AFB1) contaminant to these clays by combined batch experiment with model computation, expounded their bonding mechanisms which have been not quantitatively described by researchers. The observed adsorbent-to-solution distribution coefficients (K d ) of AFB1 presented in increasing order of 18.5-37.1, 141.6-158.3, and 354.6-484.7L/kg for kaolinite, illite, and smectite, respectively. Normalization of adsorbent-specific surface areas showed that adsorption affinity of AFB1 is mainly dependent on the outside surfaces of clay aggregates. The model computation and test of ionic effect further suggested that weakly electrostatic attractions ((Si/Al-OH) 2 ⋯(OC) 2 ) are responsible for AFB1-kaolinite adsorption (K d , 18.5-37.1L/kg); a moderate electron-donor-acceptor attraction ((CO) 2 ⋯K + ⋯(O-Al) 3 ) is related to AFB1-illite adsorption (K d , 141.6-158.3L/kg); a strong calcium-bridging linkage ((CO) 2 ⋯Ca 2+ ⋯(O-Si) 4 ) is involved in AFB1-smectite adsorption (K d , 354.6-484.7L/kg). Changes in Gibbs free energy (ΔG°) suggested that the computed result is reliable, providing a good reproduction of AFB1-clay interaction. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. The Electron Microscopy Outreach Program: A Web-based resource for research and education.

    Science.gov (United States)

    Sosinsky, G E; Baker, T S; Hand, G; Ellisman, M H

    1999-01-01

    We have developed a centralized World Wide Web (WWW)-based environment that serves as a resource of software tools and expertise for biological electron microscopy. A major focus is molecular electron microscopy, but the site also includes information and links on structural biology at all levels of resolution. This site serves to help integrate or link structural biology techniques in accordance with user needs. The WWW site, called the Electron Microscopy (EM) Outreach Program (URL: http://emoutreach.sdsc.edu), provides scientists with computational and educational tools for their research and edification. In particular, we have set up a centralized resource containing course notes, references, and links to image analysis and three-dimensional reconstruction software for investigators wanting to learn about EM techniques either within or outside of their fields of expertise. Copyright 1999 Academic Press.

  8. Identifying and evaluating electronic learning resources for use in adult-gerontology nurse practitioner education.

    Science.gov (United States)

    Thompson, Hilaire J; Belza, Basia; Baker, Margaret; Christianson, Phyllis; Doorenbos, Ardith; Nguyen, Huong

    2014-01-01

    Enhancing existing curricula to meet newly published adult-gerontology advanced practice registered nurse (APRN) competencies in an efficient manner presents a challenge to nurse educators. Incorporating shared, published electronic learning resources (ELRs) in existing or new courses may be appropriate in order to assist students in achieving competencies. The purposes of this project were to (a) identify relevant available ELR for use in enhancing geriatric APRN education and (b) to evaluate the educational utility of identified ELRs based on established criteria. A multilevel search strategy was used. Two independent team members reviewed identified ELR against established criteria to ensure utility. Only resources meeting all criteria were retained. Resources were found for each of the competency areas and included formats such as podcasts, Web casts, case studies, and teaching videos. In many cases, resources were identified using supplemental strategies and not through traditional search or search of existing geriatric repositories. Resources identified have been useful to advanced practice educators in improving lecture and seminar content in a particular topic area and providing students and preceptors with additional self-learning resources. Addressing sustainability within geriatric APRN education is critical for sharing of best practices among educators and for sustainability of teaching and related resources. © 2014.

  9. USE OF ELECTRONIC EDUCATIONAL RESOURCES WHEN TRAINING IN WORK WITH SPREADSHEETS

    Directory of Open Access Journals (Sweden)

    Х А Гербеков

    2017-12-01

    Full Text Available Today the tools for maintaining training courses based on opportunities of information and communication technologies are developed. Practically in all directions of preparation and on all subject matters electronic textbook and self-instruction manuals are created. Nevertheless the industry of computer educational and methodical materials actively develops and gets more and more areas of development and introduction. In this regard more and more urgent is a problem of development of the electronic educational resources adequate to modern educational requirements. Creation and the organization of training courses with use of electronic educational resources in particular on the basis of Internet technologies remains a difficult methodical task.In article the questions connected with development of electronic educational resources for use when studying the substantial line “Information technologies” of a school course of informatics in particular for studying of spreadsheets are considered. Also the analysis of maintenance of a school course and the unified state examination from the point of view of representation of task in him corresponding to the substantial line of studying “Information technologies” on mastering technology of information processing in spreadsheets and the methods of visualization given by means of charts and schedules is carried out.

  10. Application of Brazilian kaolinite clay as adsorbent to removal of U(VI) from aqueous solution: Kinetic and thermodynamic of cation-basic interactions

    Science.gov (United States)

    Guerra, Denis L.; Leidens, Victor L.; Viana, Rúbia R.; Airoldi, Claudio

    2010-05-01

    The compound N 1-[3-(trimethoxysilyl)propyl]diethylenetriamine was anchored onto Amazon kaolinite surface by heterogeneous route. The modified and natural kaolinite samples were characterized by transmission electron microscopy, scanning electron microscopic, X-ray diffraction, and nuclear magnetic nuclei of 29Si and 13C. The well-defined peaks obtained in the 13C NMR spectrum in the 5.0-62.1 ppm region confirmed the attachment of organic functional groups as pendant chains bonded into the porous clay. The ability of these materials to remove U(VI) from aqueous solution was followed by a series of adsorption isotherms adjusted to a Sips equation at room temperature and pH 4.0. The kinetic parameters analyzed by the Lagergren and Elovich models gave a good fit for a pseudo-second order reaction with k2 values 16.0 and 25.1 mmol g -1 min -1 ranges for natural and modified kaolinite clays, respectively. The energetic effects caused by metal ion adsorption were determined through calorimetric titrations.

  11. From Millennium ERM to Proquest 360 Resource Manager: Implementing a new Electronic Resources Management System ERMS in an International Graduate Research University in Saudi Arabia

    KAUST Repository

    Ramli, Rindra M.

    2017-01-01

    An overview of the Recommendation Study and the subsequent Implementation of a new Electronic Resources Management system ERMS in an international graduate research university in the Kingdom of Saudi Arabia. It covers the timeline, deliverables

  12. Availability, Level of Use and Constraints to Use of Electronic Resources by Law Lecturers in Public Universities in Nigeria

    Science.gov (United States)

    Amusa, Oyintola Isiaka; Atinmo, Morayo

    2016-01-01

    (Purpose) This study surveyed the level of availability, use and constraints to use of electronic resources among law lecturers in Nigeria. (Methodology) Five hundred and fifty-two law lecturers were surveyed and four hundred and forty-two responded. (Results) Data analysis revealed that the level of availability of electronic resources for the…

  13. GUIDELINES FOR EVALUATION OF PSYCHOLOGICAL AND PEDAGOGICAL QUALITY CHARACTERISTICS OF ELECTRONIC EDUCATIONAL RESOURCES

    Directory of Open Access Journals (Sweden)

    Galina P. Lavrentieva

    2014-05-01

    Full Text Available The article highlights the causes of insufficient effective use of electronic learning resources and sets out the guidelines on ways to solve the aforementioned problems. The set of didactic, methodical, psychological, pedagogical, design and ergonomic quality requirements is considered for evaluation, selection and application of information and communication technologies in the educational process. The most appropriate mechanisms for the ICT introduction into the learning process are disclosed as it should meet the specific learning needs of the student and the objectives of the educational process. The guidance for psycho-educational assessment of quality of electronic educational resources is provided. It is argued that the effectiveness of the ICT use is to be improved by means of quality evaluation mechanisms involved into the educational process.

  14. Sorption of Eu(III) to Kaolinite in the Presence of Humic Acids

    International Nuclear Information System (INIS)

    Shin, Hyun Sang; Harn, Yoon I; Oh, Se Jin

    2010-05-01

    The sorption of europium(Eu(III)) onto kaolinite and the influence of humic acids over a range of pH 3 ∼ 11 has been studied by batch adsorption experiment (V/m = 250:1 mL/g, CEu(III) = 1x10 -5 mol/L, C HA = 5 ∼ 50 mg/L, PCO 2 = 10 -3.5 atm). The concentrations of HA and Eu(III) in aqueous phase were measured by UV absorbance at 254 nm(e.g., UV 254 ) and ICP-MS after microwave digestion for HA removals, respectively. Results showed that the HA sorption onto kaolinite was decreased with increasing pH and their sorption isotherms fit well with the Langmuir adsorption model (except pH 3). Maximum amount(q max ) for the HA sorption at pH 4 to 11 was ranged from 4.73 to 0.47 mg/g. Europium adsorption onto the kaolinite in the absence of HA was typical, showing an increases with pH and a distinct adsorption edge at pH 3 to 5. However in the presence of HA, Eu adsorption to kaolinite was significantly affected. HA was shown to enhance Eu adsorption in the acidic pH range (pH 3 ∼ 4) due to the formation of additional binding sites for Eu coming from HA adsorbed onto kaolinite surface, but reduce Eu adsorption in the intermediate and high pH above 6 due to the formation of aqueous Eu-HA complexes. The results on the ternary interaction of kaolinite-Eu-HA are compared with those on the binary system of kaolinite-HA and kaolinite-Eu and adsorption mechanism with pH was discussed

  15. Flotation of kaolinite from tailings of kaolin-washing plants by cationic collectors

    OpenAIRE

    Barani Kianoush

    2016-01-01

    Traditional processing of kaolin is achieved by dispersion of the mined ore and classification by means of multistage hydrocyclones. The inefficiencies inherent to cyclones produce a middling product that is commonly disposed back to the quarry. In this research recovery of kaolinite from tailings of the Zonoupz kaolin washing plant, which is located in Iran, was investigated by cationic flotation. Flotation experiments showed that flotation of kaolinite from tailings was much better in an ac...

  16. Recovery of kaolinite from tailings of Zonouz kaolin-washing plant by flotation-flocculation method

    OpenAIRE

    Kianoush Barani; Masoud Kalantari

    2018-01-01

    The traditional processing of kaolin is achieved by dispersion of the mined ore and classification by multistage hydrocyclone plants. The inefficiencies inherent to cyclones produce a middling product that is commonly disposed back into the quarry. In this research, recovery of kaolinite from tailings of Zonouz kaolin washing plant, which is located in Iran was investigated by flotation and flotation- flocculation. Flotation experiments show that the flotation of kaolinite from the tailings i...

  17. Model of e-learning with electronic educational resources of new generation

    OpenAIRE

    A. V. Loban; D. A. Lovtsov

    2017-01-01

    Purpose of the article: improving of scientific and methodical base of the theory of the е-learning of variability. Methods used: conceptual and logical modeling of the е-learning of variability process with electronic educational resource of new generation and system analysis of the interconnection of the studied subject area, methods, didactics approaches and information and communication technologies means. Results: the formalization complex model of the е-learning of variability with elec...

  18. Kaolinite Nanocomposite Platelets Synthesized by Intercalation and Imidization of Poly(styrene-co-maleic anhydride

    Directory of Open Access Journals (Sweden)

    Pieter Samyn

    2015-07-01

    Full Text Available A synthesis route is presented for the subsequent intercalation, exfoliation and surface modification of kaolinite (Kln by an imidization reaction of high-molecular weight poly(styrene-co-maleic anhydride or SMA in the presence of ammonium hydroxide. In a first step, the intercalation of ammonolyzed SMA by guest displacement of intercalated dimethylsulfoxide has been proven. In a second step, the imidization of ammonolyzed SMA at 160 °C results in exfoliation of the kaolinite layers and deposition of poly(styrene-co-maleimide or SMI nanoparticles onto the kaolinite surfaces. Compared with a physical mixture of Kln/SMI, the chemically reacted Kln/SMI provides more efficient exfoliation and hydrogen bonding between the nanoparticles and the kaolinite. The kaolinite nanocomposite particles are synthesized in aqueous dispersion with solid content of 65 wt %. The intercalation and exfoliation are optimized for a concentration ratio of Kln/SMI = 70:30, resulting in maximum intercalation and interlayer distance in combination with highest imide content. After thermal curing at 135 °C, the imidization proceeds towards a maximum conversion of the intermediate amic acid moieties. The changes in O–H stretching and kaolinite lattice vibrations have been illustrated by infrared and FT-Raman spectroscopy, which allow for a good quantification of concentration and imidization effects.

  19. Characterization of Zeolite in Zeolite-Geopolymer Hybrid Bulk Materials Derived from Kaolinitic Clays

    Directory of Open Access Journals (Sweden)

    Hayami Takeda

    2013-05-01

    Full Text Available Zeolite-geopolymer hybrid materials have been formed when kaolin was used as a starting material. Their characteristics are of interest because they can have a wide pore size distribution with micro- and meso-pores due to the zeolite and geopolymer, respectively. In this study, Zeolite-geopolymer hybrid bulk materials were fabricated using four kinds of kaolinitic clays (a halloysite and three kinds of kaolinite. The kaolinitic clays were first calcined at 700 °C for 3 h to transform into the amorphous aluminosilicate phases. Alkali-activation treatment of the metakaolin yielded bulk materials with different amounts and types of zeolite and different compressive strength. This study investigated the effects of the initial kaolinitic clays on the amount and types of zeolite in the resultant geopolymers as well as the strength of the bulk materials. The kaolinitic clays and their metakaolin were characterized by XRD analysis, chemical composition, crystallite size, 29Si and 27Al MAS NMR analysis, and specific surface area measurements. The correlation between the amount of zeolite formed and the compressive strength of the resultant hybrid bulk materials, previously reported by other researchers was not positively observed. In the studied systems, the effects of Si/Al and crystalline size were observed. When the atomic ratio of Si/Al in the starting kaolinitic clays increased, the compressive strength of the hybrid bulk materials increased. The crystallite size of the zeolite in the hybrid bulk materials increased with decreasing compressive strength of the hybrid bulk materials.

  20. Equilibrium and kinetic studies for the sorption of 3-methoxybenzaldehyde on activated kaolinites

    Energy Technology Data Exchange (ETDEWEB)

    Koyuncu, Huelya [Forensic Medicine Foundation, Nasuhpasa Bath Street, No. 12, 16010 Heykel, Bursa (Turkey)]. E-mail: hkoyuncu@yyu.edu.tr; Kul, Ali Riza [Yuzuncu Yil University, Faculty of Art and Science, Department of Chemistry, 65080 Van (Turkey)]. E-mail: alirizakul@yyu.edu.tr; Yildiz, Nuray [Ankara University, Faculty of Engineering, Department of Chemical Engineering, 06100 Tandogan, Ankara (Turkey)]. E-mail: nyildiz@eng.ankara.edu.tr; Calimli, Ayla [Ankara University, Faculty of Engineering, Department of Chemical Engineering, 06100 Tandogan, Ankara (Turkey)]. E-mail: calimli@eng.ankara.edu.tr; Ceylan, Hasan [Yuzuncu Yil University, Faculty of Art and Science, Department of Chemistry, 65080 Van (Turkey)]. E-mail: hceylan@yyu.edu.tr

    2007-03-06

    The sorption of 3-methoxybenzaldehyde on activated kaolinites has been investigated at different temperatures. Two types of activation tests were performed. The sorption equilibrium was studied by sorption isotherms in the temperature range 303-333 K for natural (untreated), thermally and acid activated kaolinites. It was shown that the isotherm shapes were not affected by temperature and activation types of kaolinite. The absorbance data at 312 nm were fitted reasonably well with the Langmuir and Freundlich isotherm models and the model parameters were determined for different temperatures. Thermodynamic quantities such as Gibbs free energy ({delta}G), the enthalpy ({delta}H) and the entropy change of sorption ({delta}S) were determined for natural, thermally and acid activated kaolinites. It was shown that the sorption processes were an endothermic reactions, controlled by physical mechanisms and spontaneously. Adsorption capacity of acid activated kaolinite for 3-methoxybenzaldehyde was higher compared to that of natural and thermally activated kaolinites at various temperatures. The adsorption and desorption rate constants (k {sub a} and k {sub d}) were obtained separately by applying a geometric approach to the first order Langmuir model. This method provided good conformity between the K from Langmuir parameters and K {sub geo} (k {sub a}/k {sub d}) from geometric approach.

  1. Equilibrium and kinetic studies for the sorption of 3-methoxybenzaldehyde on activated kaolinites

    International Nuclear Information System (INIS)

    Koyuncu, Huelya; Kul, Ali Riza; Yildiz, Nuray; Calimli, Ayla; Ceylan, Hasan

    2007-01-01

    The sorption of 3-methoxybenzaldehyde on activated kaolinites has been investigated at different temperatures. Two types of activation tests were performed. The sorption equilibrium was studied by sorption isotherms in the temperature range 303-333 K for natural (untreated), thermally and acid activated kaolinites. It was shown that the isotherm shapes were not affected by temperature and activation types of kaolinite. The absorbance data at 312 nm were fitted reasonably well with the Langmuir and Freundlich isotherm models and the model parameters were determined for different temperatures. Thermodynamic quantities such as Gibbs free energy (ΔG), the enthalpy (ΔH) and the entropy change of sorption (ΔS) were determined for natural, thermally and acid activated kaolinites. It was shown that the sorption processes were an endothermic reactions, controlled by physical mechanisms and spontaneously. Adsorption capacity of acid activated kaolinite for 3-methoxybenzaldehyde was higher compared to that of natural and thermally activated kaolinites at various temperatures. The adsorption and desorption rate constants (k a and k d ) were obtained separately by applying a geometric approach to the first order Langmuir model. This method provided good conformity between the K from Langmuir parameters and K geo (k a /k d ) from geometric approach

  2. Hydrophobicity study of kaolinite from La Unión, Antioquia

    Directory of Open Access Journals (Sweden)

    Liliana M. Usuga-Manco

    2015-07-01

    Full Text Available In this research three methodologies to convert the hydrophilic surface of kaolinite into a hydrophobic surface are proposed, this condition is required to recover this mineral by means of froth flotation. Taking into account the anisotropy, zeta potential and complex surface electrical properties of the kaolinite, three surface chemical treatments based on the interacting and absorption of anionic collectors onto the mineral surface, causing an increase in the contact angle and thus increased hydrophobicity of kaolinite were applied. The methodologies proposed were interactions of kaolinite particles with: sodium dodecyl sulfate solutions with concentration 1x10-3M, 1x10-4M, 1x10-5M; sodium dodecyl sulfate solutions 1x10-3M, 1x10-4M, 1x10-5M with further interaction with kerosene solutions 127000 ppm; and oleic acid solutions 1x10-3M, 1x10-4M, 1x10-5M, each one with a five minutes of interaction. The experimental results obtained by zeta potential and contact angle of the kaolinite before and after applying chemical treatments indicate that larger the chain length of the collector and its concentration, bigger the contact angle and so, more hydrophobic the surface (edge or face. In order to optimize, control and understand this solid-liquid interaction phenomenon is suggested to find out about the hydrophobization mechanism of kaolinite with oleic acid and its percentage of hydrophobization.

  3. A systematic review of portable electronic technology for health education in resource-limited settings.

    Science.gov (United States)

    McHenry, Megan S; Fischer, Lydia J; Chun, Yeona; Vreeman, Rachel C

    2017-08-01

    The objective of this study is to conduct a systematic review of the literature of how portable electronic technologies with offline functionality are perceived and used to provide health education in resource-limited settings. Three reviewers evaluated articles and performed a bibliography search to identify studies describing health education delivered by portable electronic device with offline functionality in low- or middle-income countries. Data extracted included: study population; study design and type of analysis; type of technology used; method of use; setting of technology use; impact on caregivers, patients, or overall health outcomes; and reported limitations. Searches yielded 5514 unique titles. Out of 75 critically reviewed full-text articles, 10 met inclusion criteria. Study locations included Botswana, Peru, Kenya, Thailand, Nigeria, India, Ghana, and Tanzania. Topics addressed included: development of healthcare worker training modules, clinical decision support tools, patient education tools, perceptions and usability of portable electronic technology, and comparisons of technologies and/or mobile applications. Studies primarily looked at the assessment of developed educational modules on trainee health knowledge, perceptions and usability of technology, and comparisons of technologies. Overall, studies reported positive results for portable electronic device-based health education, frequently reporting increased provider/patient knowledge, improved patient outcomes in both quality of care and management, increased provider comfort level with technology, and an environment characterized by increased levels of technology-based, informal learning situations. Negative assessments included high investment costs, lack of technical support, and fear of device theft. While the research is limited, portable electronic educational resources present promising avenues to increase access to effective health education in resource-limited settings, contingent

  4. Adhesion of the clay minerals montmorillonite, kaolinite, and attapulgite reduces respiration of Histoplasma capsulatum.

    Science.gov (United States)

    Lavie, S; Stotzky, G

    1986-01-01

    The respiration of three phenotypes of Histoplasma capsulatum, the causal agent of histoplasmosis in humans, was markedly reduced by low concentrations of montmorillonite but was reduced less by even higher concentrations of kaolinite or attapulgite (palygorskite). The reduction in respiration followed a pattern that suggested saturation-type kinetics: an initial sharp reduction that occurred with low concentrations of clay (0.01 to 0.5% [wt/vol]), followed by a more gradual reduction with higher concentrations (1 to 8%). Increases in viscosity (which could impair the movement of O2) caused by the clays were not responsible for the reduction in respiration, and the clays did not interfere with the availability of nutrients. Scanning electron microscopy after extensive washing showed that the clay particles were tightly bound to the hyphae, suggesting that the clays reduced the rate of respiration of H. capsulatum by adhering to the mycelial surface and, thereby, interfered with the movement of nutrients, metabolites, and gases across the mycelial wall.

  5. Model of e-learning with electronic educational resources of new generation

    Directory of Open Access Journals (Sweden)

    A. V. Loban

    2017-01-01

    Full Text Available Purpose of the article: improving of scientific and methodical base of the theory of the е-learning of variability. Methods used: conceptual and logical modeling of the е-learning of variability process with electronic educational resource of new generation and system analysis of the interconnection of the studied subject area, methods, didactics approaches and information and communication technologies means. Results: the formalization complex model of the е-learning of variability with electronic educational resource of new generation is developed, conditionally decomposed into three basic components: the formalization model of the course in the form of the thesaurusclassifier (“Author of e-resource”, the model of learning as management (“Coordination. Consultation. Control”, the learning model with the thesaurus-classifier (“Student”. Model “Author of e-resource” allows the student to achieve completeness, high degree of didactic elaboration and structuring of the studied material in triples of variants: modules of education information, practical task and control tasks; the result of the student’s (author’s of e-resource activity is the thesaurus-classifier. Model of learning as management is based on the principle of personal orientation of learning in computer environment and determines the logic of interaction between the lecturer and the student when determining the triple of variants individually for each student; organization of a dialogue between the lecturer and the student for consulting purposes; personal control of the student’s success (report generation and iterative search for the concept of the class assignment in the thesaurus-classifier before acquiring the required level of training. Model “Student” makes it possible to concretize the learning tasks in relation to the personality of the student and to the training level achieved; the assumption of the lecturer about the level of training of a

  6. Polyacrylic acid grafted kaolinite via a facile ‘grafting to’ approach based on heterogeneous esterification and its adsorption for Cu2+

    Science.gov (United States)

    Zhao, Ping; Zhou, Qi; Yan, Chunjie; Luo, Wenjun

    2017-03-01

    Kaolinite (KLN) was successfully decorated by polyacrylic acid (PAA) brushes via a facile ‘one-step’ manner in this study. This process was achieved by heterogeneous esterification between carboxyl on the PAA chains and hydroxyl on the KLN in the presence of Al3+ as catalyst. The prepared composite (denoted as PAA-g-KLN) was characterized by Fourier transform infrared spectroscopy (FTIR), x-ray diffraction pattern (XRD), Field emission scanning electron microscopy (FE-SEM) and thermogravimetry (TG) to confirm the successful grafting of PAA brushes on the surface of KLN. Subsequently, the PAA-g-KLN was used as adsorbent for the removal of Cu2+ from wastewater. Due to the introduction of abundant and highly accessible carboxyl groups on the surface of kaolinite, PAA-g-KLN exhibited an enhanced adsorption performance than raw kaolinite, which could be up to 32.45 mg·g-1 at 45 °C with a fast adsorption kinetic. Theoretical models analysis revealed that Langmuir isotherm model and the pseudo second-order model were more suitable for well elucidation of the experimental data. In addition, the regeneration experiment showed that the PAA-g-KLN could still keep a satisfactory adsorption capacity (>65%) by being reused for 6 consecutive cycles. The study provides an easy and rapid method for surface polyelectrolyte modification on inorganic mineral as a promising adsorbent to remove Cu2+ from aqueous solution.

  7. Role of Organic Acids in Bioformation of Kaolinite: Results of Laboratory Experiments

    Science.gov (United States)

    Bontognali, T. R. R.; Vasconcelos, C.; McKenzie, J. A.

    2012-04-01

    Clay minerals and other solid silica phases have a broad distribution in the geological record and greatly affect fundamental physicochemical properties of sedimentary rocks, including porosity. An increasing number of studies suggests that microbial activity and microbially produced organic acids might play an important role in authigenic clay mineral formation, at low temperatures and under neutral pH conditions. In particular, early laboratory experiments (Linares and Huertas, 1971) reported the precipitation of kaolinite in solutions of SiO2 and Al2O3 with different molar ratios SiO2/Al2O3, together with fulvic acid (a non-characterized mixture of many different acids containing carboxyl and phenolate groups) that was extracted from peat soil. Despite many attempts, these experiments could not be reproduced until recently. Fiore et al. (2011) hypothesized that the non-sterile fulvic acid might have contained microbes that participated in the formation of kaolinite. Using solutions saturated with Si and Al and containing oxalate and/or mixed microbial culture extracted from peat-moss soil, they performed incubation experiments, which produced kaolinite exclusively in solutions containing oxalate and microbes. We proposed to test the role of specific organic acids for kaolinite formation, conducting laboratory experiments at 25˚C, with solutions of sodium silicate, aluminum chloride and various organic compounds (i.e. EDTA, citric acid, succinic acid and oxalic acid). Specific organic acids may stabilize aluminum in octahedral coordination positions, which is crucial for the initial nucleation step. In our experiments, a poorly crystalline mineral that is possibly a kaolinite precursor formed exclusively in the presence of succinic acid. In experiments with other organic compounds, no incorporation of Al was observed, and amorphous silica was the only precipitated phase. In natural environments, succinic acid is produced by a large variety of microbes as an

  8. Review of material recovery from used electric and electronic equipment-alternative options for resource conservation.

    Science.gov (United States)

    Friege, Henning

    2012-09-01

    For waste from electric and electronic equipment, the WEEE Directive stipulates the separate collection of electric and electronic waste. As to new electric and electronic devices, the Restriction of Hazardous Substances (RoHS) Directive bans the use of certain chemicals dangerous for man and environment. From the implementation of the WEEE directive, many unsolved problems have been documented: poor collection success, emission of dangerous substances during collection and recycling, irretrievable loss of valuable metals among others. As to RoHS, data from the literature show a satisfying success. The problems identified in the process can be reduced to some basic dilemmas at the borders between waste management, product policy and chemical safety. The objectives of the WEEE Directive and the specific targets for use and recycling of appliances are not consistent. There is no focus on scarce resources. Extended producer responsibility is not sufficient to guarantee sustainable waste management. Waste management reaches its limits due to problems of implementation but also due to physical laws. A holistic approach is necessary looking at all branch points and sinks in the stream of used products and waste from electric and electronic equipment. This may be done with respect to the general rules for sustainable management of material streams covering the three dimensions of sustainable policy. The relationships between the players in the field of electric and electronic devices have to be taken into account. Most of the problems identified in the implementation process will not be solved by the current amendment of the WEEE Directive.

  9. A spectroscopic study of mechanochemically activated kaolinite with the aid of chemometrics.

    Science.gov (United States)

    Carmody, Onuma; Kristóf, János; Frost, Ray L; Makó, Eva; Kloprogge, J Theo; Kokot, Serge

    2005-07-01

    The study of kaolinite surfaces is of industrial importance. In this work we report the application of chemometrics to the study of modified kaolinite surfaces. DRIFT spectra of mechanochemically activated kaolinites (Kiralyhegy, Zettlitz, Szeg, and Birdwood) were analyzed using principal component analysis (PCA) and multicriteria decision making (MCDM) methods, PROMETHEE and GAIA. The clear discrimination of the Kiralyhegy spectral objects on the two PC scores plots (400-800 and 800-2030 cm(-1)) indicated the dominance of quartz. Importantly, no ordering of any spectral objects appeared to be related to grinding time in the PC plots of these spectral regions. Thus, neither the kaolinite nor the quartz, are systematically responsive to grinding time according to the spectral criteria investigated. The third spectral region (2600-3800 cm(-1)OH vibrations), showed apparent systematic ordering of the Kiralyhegy and, to a lesser extent, Zettlitz spectral objects with grinding time. This was attributed to the effect of the natural quartz on the delamination of kaolinite and the accompanying phenomena (i.e., formation of kaolinite spheres and water). With the MCDM methods, it was shown that useful information on the basis of chemical composition, physical properties and grinding time can be obtained. For example, the effects of the minor chemical components (e.g., MgO, K(2)O, etc.) indicated that the Birdwood kaolinite is arguably the most pure one analyzed. In another MCDM experiment, some support was obtained for the apparent trend with grinding time noted in the PC plot of the OH spectral region.

  10. [Use of internet and electronic resources among Spanish intensivist physicians. First national survey].

    Science.gov (United States)

    Gómez-Tello, V; Latour-Pérez, J; Añón Elizalde, J M; Palencia-Herrejón, E; Díaz-Alersi, R; De Lucas-García, N

    2006-01-01

    Estimate knowledge and use habits of different electronic resources in a sample of Spanish intensivists: Internet, E-mail, distribution lists, and use of portable electronic devices. Self-applied questionnaire. A 50-question questionnaire was distributed among Spanish intensivists through the hospital marketing delegates of a pharmaceutical company and of electronic forums. A total of 682 questionnaires were analyzed (participation: 74%). Ninety six percent of those surveyed used Internet individually: 67% admitted training gap. Internet was the second source of clinical consultations most used (61%), slightly behind consultation to colleagues (65%). The pages consulted most were bibliographic databases (65%) and electronic professional journals (63%), with limited use of Evidence Based Medicine pages (19%). Ninety percent of those surveyed used e-mail regularly in the practice of their profession, although 25% admitted that were not aware of its possibilities. The use of E-mail decreased significantly with increase in age. A total of 62% of the intensivists used distribution lists. Of the rest, 42% were not aware of its existence and 32% admitted they had insufficient training to handle them. Twenty percent of those surveyed had portable electronic devices and 64% considered it useful, basically due to its rapid consultation at bedside. Female gender was a negative predictive factor of its use (OR 0.35; 95% CI 0.2-0.63; p=0.0002). A large majority of the Spanish intensivists use Internet and E-mail. E-mail lists and use of portable devices are still underused resources. There are important gaps in training and infrequent use of essential pages. There are specific groups that require directed educational policies.

  11. Adsorption of Zn(II) on the kaolinite(001) surfaces in aqueous environment: A combined DFT and molecular dynamics study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qiang; Kong, Xiang-Ping; Zhang, Bao-Hua; Wang, Juan, E-mail: juaner80@163.com

    2017-08-31

    Highlights: • Zn(II) adsorption on two types of neutral kaolinite(001) surfaces is investigated. • Surface “Ou” is found the preferred site for mono- and bi-dentate complexes. • Both Zn(II) and surface oxygen accept electrons from aqua oxygens. • Coupling of O 2p with Zn sp{sup 3}d{sup 2} (or sp{sup 3}) hybridization states is the bonding nature. - Abstract: Adsorption of Zn(II) on two types of neutral (001) surfaces of kaolinite, tetrahedral Si(t) and octahedral Al(o), was studied by means of DFT calculations and classical molecular dynamics simulations. The position and structure for both outer-sphere and mono-/bi-dentate inner-sphere complexes of Zn(II) in aqueous environment were examined, with binding energy and radial distribution function calculated. Outer-sphere complex on the Si(t) surface, monodentate inner-sphere complex of “O{sub u}” (surface oxygen with “upright” hydrogen) site and bidentate complex of “O{sub u}-O{sub u}” site of neighboring Al centers on the Al(o) surface are considered to be the dominant adsorption species. The outer-sphere complex is found six-coordinated with distorted octahedral geometry, while both the inner-sphere complexes exhibit the tetrahedral structure with coordination number of four. Hydrogen bonding interactions between oxygen or hydrogen of the kaolinite(001) surfaces and the aqua ligands of Zn(II) act as the key role for the structure and stability of adsorption complexes. Upon the Mulliken population analysis and partial density of states, both Zn(II) and surface oxygen accept electrons from aqua oxygens, and coupling of O 2p with the sp{sup 3}d{sup 2} or sp{sup 3} hybridization states of Zn(II) is the primary bonding nature of Zn(II) with oxygen in outer- and inner-sphere complexes, respectively.

  12. The Synthesis of the Hierarchical Structure of Information Resources for Management of Electronic Commerce Entities

    Directory of Open Access Journals (Sweden)

    Krutova Anzhelika S.

    2017-06-01

    Full Text Available The aim of the article is to develop the theoretical bases for the classification and coding of economic information and the scientific justification of the content of information resources of an electronic commerce enterprise. The essence of information resources for management of electronic business entities is investigated. It is proved that the organization of accounting in e-commerce systems is advisable to be built on the basis of two circuits: accounting for financial flows and accounting associated with transformation of business factors in products and services as a result of production activities. There presented a sequence of accounting organization that allows to combine the both circuits in a single information system, which provides a possibility for the integrated replenishment and distributed simultaneous use of the e-commerce system by all groups of users. It is proved that the guarantee of efficient activity of the information management system of electronic commerce entities is a proper systematization of the aggregate of information resources on economic facts and operations of an enterprise in accordance with the management tasks by building the hierarchy of accounting nomenclatures. It is suggested to understand nomenclature as an objective, primary information aggregate concerning a certain fact of the economic activity of an enterprise, which is characterized by minimum requisites, is entered into the database of the information system and is to be reflected in the accounting system. It is proposed to build a database of e-commerce systems as a part of directories (constants, personnel, goods / products, suppliers, buyers and the hierarchy of accounting nomenclatures. The package of documents regulating the organization of accounting at an enterprise should include: the provision on the accounting services, the order on the accounting policy, the job descriptions, the schedules of information exchange, the report card and

  13. Nucleation and growth process of sodalite and cancrinite from kaolinite-rich clay under low-temperature hydrothermal conditions

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Ríos Reyes

    2013-04-01

    Full Text Available The synthesis of low-silica zeotypes by hydrothermal transformation of kaolinite-rich clay and the nucleation and growth processes of sodalite and cancrinite in the system Na2O-Al2O3-SiO2-H2O at 100 °C were investigated. The synthesis products were characterized by X-ray powder diffraction (XRPD, scanning electron microscopy (SEM, Fourier transform infrared spectroscopy (FT-IR, 29Si and 27Al Magic Angle Spinning Nuclear Magnetic Resonance (MAS-NMR and thermogravimetric analysis (TGA. Our data show that the sequence of the transformation of phases is: Poorly crystalline aluminosilicate → zeolite LTA → sodalite → sodalite + cancrinite → cancrinite. Synthesized materials appeared stable thermodynamically under the experimental conditions, with zeolite LTA (a metastable phase occurring as a minor phase, compared with the presence of sodalite and cancrinite.

  14. Kaolinite, illite and quartz dissolution in the karstification of Paleozoic sandstones of the Furnas Formation, Paraná Basin, Southern Brazil

    Science.gov (United States)

    Melo, Mário Sérgio de; Guimarães, Gilson Burigo; Chinelatto, Adilson Luiz; Giannini, Paulo César Fonseca; Pontes, Henrique Simão; Chinelatto, Adriana Scoton Antonio; Atencio, Daniel

    2015-11-01

    Karstification processes in sandstones of the Furnas Formation, Silurian to Devonian of the Paraná Basin, have been described since the mid-twentieth century. However, some geologists still doubt the idea of true karst in sandstones. Studies carried out in the Campos Gerais region, Paraná State, Southern Brazil, aimed at investigating the nature of erosion processes in Furnas Formation and the role of the dissolution in the development of their notorious erosive features and underground cavities. These studies have led to the recognition of dissolution macro to micro features ('furnas', caves, ponds, sinks, ruiniform relief on cliffs and rocky surfaces, grain corrosion, speleothems, mineral reprecipitation and incrustation). The analysis (scanning electron microscopy, energy dispersive spectrometry and x-ray diffractometry) of sandstones and their alterites has indicated significant dissolution of clay cement along with discrete quartz grain dissolution. This mesodiagenetic cement (kaolinite and illite) is dissolved and reprecipitated as clay minerals with poorly developed crystallinity along with other minerals, such as variscite and minerals of the alunite supergroup, suggesting organic participation in the processes of dissolution and incrustation. The mineral reprecipitation usually forms centimetric speleothems, found in cavities and sheltered rocky surfaces. The cement dissolution associated with other factors (fractures, wet weather, strong hydraulic gradient, antiquity of the landforms) leads to the rock arenisation, the underground erosion and the appearance of the karst features. Carbonate rocks in the basement may locally be increasing the karst forms in the overlying Furnas Formation. The recognition of the karst character of the Furnas Formation sandstones has important implications in the management of underground water resources (increasingly exploited in the region), in the use of the unique geological heritage and in the prevention of geo

  15. ELECTRONIC EDUCATIONAL RESOURCES FOR ONLINE SUPPORT OF MODERN CHEMISTRY CLASSES IN SPECIALIZED SCHOOL

    Directory of Open Access Journals (Sweden)

    Maria D. Tukalo

    2013-09-01

    Full Text Available This article contains material of some modern electronic educational resources that can be used via the Internet to support the modern chemistry classes in specialized school. It was drawn attention to the educational chemical experiments as means of knowledge; simulated key motivational characteristics to enhance students interest for learning subjects, their cognitive and practical activity in the formation of self-reliance and self-creative; commented forecasts for creating of conditions to enhance the creative potential of students in a modern learning environment.

  16. Neptunium(V) sorption onto kaolinite in the absence and presence of CO2

    International Nuclear Information System (INIS)

    Amayri, S.; Reich, Ta.; Reich, T.

    2005-01-01

    Full text of publication follows: The adsorption of heavy metals on clay minerals such as kaolinite is an important process that affects the migration and retardation of neptunium and other actinides in the geosphere. The sorption of Np(V) onto the reference clay mineral kaolinite KGa-1b was investigated both by batch experiments and EXAFS measurements. The aim of our study was to combine macroscopic studies (batch experiments) with microscopic techniques (EXAFS) to study the Np(V) speciation at the kaolinite surface. The batch experiments were done under relevant environmental conditions with Np(V) concentrations of 10 -11 and 10 -12 mol/L. Sorption samples were prepared in 0.1 mol/L NaClO 4 , 4 g/L kaolinite, pH 6.0 to 10.5, presence and absence of ambient CO 2 , and 60-h equilibration. The sorption curves for 10 -11 and 10 -12 mol/L Np(V) obtained in the presence and absence of CO 2 , respectively, show that the adsorption edge occurs at pH 8.5. The uptake of Np(V) by kaolinite strongly increased above pH 7.0 and reached its sorption maximum (70 %) at pH 9.0. Above pH 9.0, the amount of Np(V) sorbed onto kaolinite decreased and reached ca. 30 % at pH 10.5 due to the formation of Np(V) carbonato species in the aqueous solution. In the CO 2 -free system, the sorption of Np(V) increased continuously with pH until the sorption maximum of 100 % was reached at pH 10.5. The same sorption behavior was found in batch experiments in the CO 2 equilibrated system with Np concentrations ranging from 1 μmol/L to 10 μmol/L. EXAFS experiments on some of these batch samples indicated the formation of Np(V) carbonato species at the kaolinite surface at pH 9.0 where the uptake of Np(V) by kaolinite reaches its maximum [1]. [1] T. Reich, S. Amayri, Ta. Reich, J. Drebert, A. Jermolajev, P. Thoerle, N. Trautmann, C. Hennig, S. Sachs, Feasibility of EXAFS experiments at the Np L-edge to investigate neptunium sorption on kaolinite, Institut fuer Kernchemie, Universitaet Mainz, Annual

  17. In situ neutron diffraction investigation on the phase transformation sequence of kaolinite and halloysite to mullite

    Energy Technology Data Exchange (ETDEWEB)

    Tezuka, Nobuo [Department of Applied Physics, Curtin University of Technology, GPO Box U1987, Perth, WA 6845 (Australia); Low, It-Meng [Department of Applied Physics, Curtin University of Technology, GPO Box U1987, Perth, WA 6845 (Australia)]. E-mail: J.Low@curtin.edu.au; Davies, Ian J. [Department of Mechanical Engineering, Curtin University of Technology, GPO Box U1987, Perth, WA 6845 (Australia); Prior, Michael [Bragg Institute, ANSTO, PMB 1, Menai, NSW 2234 (Australia); Studer, Andrew [Bragg Institute, ANSTO, PMB 1, Menai, NSW 2234 (Australia)

    2006-11-15

    'Kaolin' is a major raw material for the fabrication of conventional ceramics. In this work the authors have investigated the thermal phase transformation of mullite from two different types of kaolin (kaolinite and halloysite), with or without alumina matrix constraint, during heating up to 1500 deg. C and then cooling using in situ neutron diffraction. Mullitization was initiated upon heating to 1200 deg. C for all specimens and followed spinel formation at 1100 deg. C. Above this temperature, however, evolution of the main phases, i.e., mullite, cristobalite and corundum, was influenced by the presence of impurities, initial type of silica, and alumina constraint. The relative amount of mullite was largest for the pure kaolinite specimen, particularly during heating, and this was attributed to the presence of a glassy phase. However, kaolinite with alumina suppressed the crystallization of cristobalite from the glassy phase upon cooling due to a reaction between alumina and amorphous silica, consequently resulting in an amount of mullite as for the pure kaolinite specimen (approximately 65 wt%). Halloysite was less active in terms of mullitization due to the lower level of initial impurities and greater amount of cristobalite, particularly for the alumina-constrained specimen. However, the final amount of mullite derived from the pure halloysite specimen was similar to that as from the kaolinite specimen.

  18. Infrared and infrared emission spectroscopic study of typical Chinese kaolinite and halloysite.

    Science.gov (United States)

    Cheng, Hongfei; Frost, Ray L; Yang, Jing; Liu, Qinfu; He, Junkai

    2010-12-01

    The structure and thermal stability between typical Chinese kaolinite and halloysite were analysed by X-ray diffraction (XRD), infrared spectroscopy, infrared emission spectroscopy (IES) and Raman spectroscopy. Infrared emission spectroscopy over the temperature range of 300-700°C has been used to characterise the thermal decomposition of both kaolinite and halloysite. Halloysite is characterised by two bands in the water bending region at 1629 and 1648 cm(-1), attributed to structural water and coordinated water in the interlayer. Well defined hydroxyl stretching bands at around 3695, 3679, 3652 and 3625 cm(-1) are observed for both kaolinite and halloysite. The 550°C infrared emission spectrum of halloysite is similar to that of kaolinite in 650-1350 cm(-1) spectral region. The infrared emission spectra of halloysite were found to be considerably different to that of kaolinite at lower temperatures. These differences are attributed to the fundamental difference in the structure of the two minerals. Copyright © 2010 Elsevier B.V. All rights reserved.

  19. In situ neutron diffraction investigation on the phase transformation sequence of kaolinite and halloysite to mullite

    International Nuclear Information System (INIS)

    Tezuka, Nobuo; Low, It-Meng; Davies, Ian J.; Prior, Michael; Studer, Andrew

    2006-01-01

    'Kaolin' is a major raw material for the fabrication of conventional ceramics. In this work the authors have investigated the thermal phase transformation of mullite from two different types of kaolin (kaolinite and halloysite), with or without alumina matrix constraint, during heating up to 1500 deg. C and then cooling using in situ neutron diffraction. Mullitization was initiated upon heating to 1200 deg. C for all specimens and followed spinel formation at 1100 deg. C. Above this temperature, however, evolution of the main phases, i.e., mullite, cristobalite and corundum, was influenced by the presence of impurities, initial type of silica, and alumina constraint. The relative amount of mullite was largest for the pure kaolinite specimen, particularly during heating, and this was attributed to the presence of a glassy phase. However, kaolinite with alumina suppressed the crystallization of cristobalite from the glassy phase upon cooling due to a reaction between alumina and amorphous silica, consequently resulting in an amount of mullite as for the pure kaolinite specimen (approximately 65 wt%). Halloysite was less active in terms of mullitization due to the lower level of initial impurities and greater amount of cristobalite, particularly for the alumina-constrained specimen. However, the final amount of mullite derived from the pure halloysite specimen was similar to that as from the kaolinite specimen

  20. A role for subducted super-hydrated kaolinite in Earth’s deep water cycle

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Huijeong; Seoung, Donghoon; Lee, Yongjae; Liu, Zhenxian; Liermann, Hanns-Peter; Cynn, Hyunchae; Vogt, Thomas; Kao, Chi-Chang; Mao, Ho-Kwang

    2017-11-20

    Water is the most abundant volatile component in the Earth. It continuously enters the mantle through subduction zones, where it reduces the melting temperature of rocks to generate magmas. The dehydration process in subduction zones, which determines whether water is released from the slab or transported into the deeper mantle, is an essential component of the deep water cycle. Here we use in situ and time-resolved high-pressure/high-temperature synchrotron X-ray diffraction and infrared spectra to characterize the structural and chemical changes of the clay mineral kaolinite. At conditions corresponding to a depth of about 75 km in a cold subducting slab (2.7 GPa and 200 °C), and in the presence of water, we observe the pressure-induced insertion of water into kaolinite. This super-hydrated phase has a unit cell volume that is about 31% larger, a density that is about 8.4% lower than the original kaolinite and, with 29 wt% H2O, the highest water content of any known aluminosilicate mineral in the Earth. As pressure and temperature approach 19 GPa and about 800 °C, we observe the sequential breakdown of super-hydrated kaolinite. The formation and subsequent breakdown of super-hydrated kaolinite in cold slabs subducted below 200 km leads to the release of water that may affect seismicity and help fuel arc volcanism at the surface.

  1. A role for subducted super-hydrated kaolinite in Earth's deep water cycle

    Science.gov (United States)

    Hwang, Huijeong; Seoung, Donghoon; Lee, Yongjae; Liu, Zhenxian; Liermann, Hanns-Peter; Cynn, Hyunchae; Vogt, Thomas; Kao, Chi-Chang; Mao, Ho-Kwang

    2017-12-01

    Water is the most abundant volatile component in the Earth. It continuously enters the mantle through subduction zones, where it reduces the melting temperature of rocks to generate magmas. The dehydration process in subduction zones, which determines whether water is released from the slab or transported into the deeper mantle, is an essential component of the deep water cycle. Here we use in situ and time-resolved high-pressure/high-temperature synchrotron X-ray diffraction and infrared spectra to characterize the structural and chemical changes of the clay mineral kaolinite. At conditions corresponding to a depth of about 75 km in a cold subducting slab (2.7 GPa and 200 °C), and in the presence of water, we observe the pressure-induced insertion of water into kaolinite. This super-hydrated phase has a unit cell volume that is about 31% larger, a density that is about 8.4% lower than the original kaolinite and, with 29 wt% H2O, the highest water content of any known aluminosilicate mineral in the Earth. As pressure and temperature approach 19 GPa and about 800 °C, we observe the sequential breakdown of super-hydrated kaolinite. The formation and subsequent breakdown of super-hydrated kaolinite in cold slabs subducted below 200 km leads to the release of water that may affect seismicity and help fuel arc volcanism at the surface.

  2. Recovery of kaolinite from tailings of Zonouz kaolin-washing plant by flotation-flocculation method

    Directory of Open Access Journals (Sweden)

    Kianoush Barani

    2018-04-01

    Full Text Available The traditional processing of kaolin is achieved by dispersion of the mined ore and classification by multistage hydrocyclone plants. The inefficiencies inherent to cyclones produce a middling product that is commonly disposed back into the quarry. In this research, recovery of kaolinite from tailings of Zonouz kaolin washing plant, which is located in Iran was investigated by flotation and flotation- flocculation. Flotation experiments show that the flotation of kaolinite from the tailings is better in an acidic than in an alkaline medium containing cationic collectors. Flotation under acidic condition causes problems such as equipment corrosion at industrial scale. As a result, the cationic flotation of kaolinite is enhanced by addition of polyacrylamide as a flocculant. The results showed flocculation by polyacrylamide improved flotation of kaolinite within a range of pH. With 300 g/t dodecylamine, 500 g/t aluminum chloride, 50 g/t pine oil (frother, 15 g/t polyacrylamide, at pH = 7 and without de-slimming a product has 37.19% Al2O3, 54.19% SiO2 and 34.43% mass recovery was archived. Keywords: Kaolinite, Flotation, Flocculation, Cetylpyridinium chloride, Dodecylamine, Aluminum chloride, Polyacrylamide

  3. THE MODEL OF LINGUISTIC TEACHERS’ COMPETENCY DEVELOPMENT ON DESIGNING MULTIMEDIA ELECTRONIC EDUCATIONAL RESOURCES IN THE MOODLE SYSTEM

    Directory of Open Access Journals (Sweden)

    Anton M. Avramchuk

    2017-10-01

    Full Text Available The article is devoted to the problem of developing the competency of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system. The concept of "the competence of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system" is justified and defined. Identified and characterized the components by which the levels of the competency development of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system should be assessed. Developed a model for the development of the competency of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system, which is based on the main scientific approaches, used in adult education, and consists of five blocks: target, informative, technological, diagnostic and effective.

  4. A preliminary categorization of end-of-life electrical and electronic equipment as secondary metal resources

    International Nuclear Information System (INIS)

    Oguchi, Masahiro; Murakami, Shinsuke; Sakanakura, Hirofumi; Kida, Akiko; Kameya, Takashi

    2011-01-01

    Highlights: → End-of-life electrical and electronic equipment (EEE) as secondary metal resources. → The content and the total amount of metals in specific equipment are both important. → We categorized 21 EEE types from contents and total amounts of various metals. → Important equipment types as secondary resources were listed for each metal kind. → Collectability and possible collection systems of various EEE types were discussed. - Abstract: End-of-life electrical and electronic equipment (EEE) has recently received attention as a secondary source of metals. This study examined characteristics of end-of-life EEE as secondary metal resources to consider efficient collection and metal recovery systems according to the specific metals and types of EEE. We constructed an analogy between natural resource development and metal recovery from end-of-life EEE and found that metal content and total annual amount of metal contained in each type of end-of-life EEE should be considered in secondary resource development, as well as the collectability of the end-of-life products. We then categorized 21 EEE types into five groups and discussed their potential as secondary metal resources. Refrigerators, washing machines, air conditioners, and CRT TVs were evaluated as the most important sources of common metals, and personal computers, mobile phones, and video games were evaluated as the most important sources of precious metals. Several types of small digital equipment were also identified as important sources of precious metals; however, mid-size information and communication technology (ICT) equipment (e.g., printers and fax machines) and audio/video equipment were shown to be more important as a source of a variety of less common metals. The physical collectability of each type of EEE was roughly characterized by unit size and number of end-of-life products generated annually. Current collection systems in Japan were examined and potentially appropriate collection

  5. Open-Source Electronic Health Record Systems for Low-Resource Settings: Systematic Review.

    Science.gov (United States)

    Syzdykova, Assel; Malta, André; Zolfo, Maria; Diro, Ermias; Oliveira, José Luis

    2017-11-13

    Despite the great impact of information and communication technologies on clinical practice and on the quality of health services, this trend has been almost exclusive to developed countries, whereas countries with poor resources suffer from many economic and social issues that have hindered the real benefits of electronic health (eHealth) tools. As a component of eHealth systems, electronic health records (EHRs) play a fundamental role in patient management and effective medical care services. Thus, the adoption of EHRs in regions with a lack of infrastructure, untrained staff, and ill-equipped health care providers is an important task. However, the main barrier to adopting EHR software in low- and middle-income countries is the cost of its purchase and maintenance, which highlights the open-source approach as a good solution for these underserved areas. The aim of this study was to conduct a systematic review of open-source EHR systems based on the requirements and limitations of low-resource settings. First, we reviewed existing literature on the comparison of available open-source solutions. In close collaboration with the University of Gondar Hospital, Ethiopia, we identified common limitations in poor resource environments and also the main requirements that EHRs should support. Then, we extensively evaluated the current open-source EHR solutions, discussing their strengths and weaknesses, and their appropriateness to fulfill a predefined set of features relevant for low-resource settings. The evaluation methodology allowed assessment of several key aspects of available solutions that are as follows: (1) integrated applications, (2) configurable reports, (3) custom reports, (4) custom forms, (5) interoperability, (6) coding systems, (7) authentication methods, (8) patient portal, (9) access control model, (10) cryptographic features, (11) flexible data model, (12) offline support, (13) native client, (14) Web client,(15) other clients, (16) code

  6. THE MODEL OF LINGUISTIC TEACHERS’ COMPETENCY DEVELOPMENT ON DESIGNING MULTIMEDIA ELECTRONIC EDUCATIONAL RESOURCES IN THE MOODLE SYSTEM

    OpenAIRE

    Anton M. Avramchuk

    2017-01-01

    The article is devoted to the problem of developing the competency of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system. The concept of "the competence of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system" is justified and defined. Identified and characterized the components by which the levels of the competency development of teachers of language disciplines on designing ...

  7. Determining the level of awareness of the physicians in using the variety of electronic information resources and the effecting factors.

    Science.gov (United States)

    Papi, Ahmad; Ghazavi, Roghayeh; Moradi, Salimeh

    2015-01-01

    Understanding of the medical society's from the types of information resources for quick and easy access to information is an imperative task in medical researches and management of the treatment. The present study was aimed to determine the level of awareness of the physicians in using various electronic information resources and the factors affecting it. This study was a descriptive survey. The data collection tool was a researcher-made questionnaire. The study population included all the physicians and specialty physicians of the teaching hospitals affiliated to Isfahan University of Medical Sciences and numbered 350. The sample size based on Morgan's formula was set at 180. The content validity of the tool was confirmed by the library and information professionals and the reliability was 95%. Descriptive statistics were used including the SPSS software version 19. On reviewing the need of the physicians to obtain the information on several occasions, the need for information in conducting the researches was reported by the maximum number of physicians (91.9%) and the usage of information resources, especially the electronic resources, formed 65.4% as the highest rate with regard to meeting the information needs of the physicians. Among the electronic information databases, the maximum awareness was related to Medline with 86.5%. Among the various electronic information resources, the highest awareness (43.3%) was related to the E-journals. The highest usage (36%) was also from the same source. The studied physicians considered the most effective deterrent in the use of electronic information resources as being too busy and lack of time. Despite the importance of electronic information resources for the physician's community, there was no comprehensive knowledge of these resources. This can lead to less usage of these resources. Therefore, careful planning is necessary in the hospital libraries in order to introduce the facilities and full capabilities of the

  8. Success criteria for electronic medical record implementations in low-resource settings: a systematic review.

    Science.gov (United States)

    Fritz, Fleur; Tilahun, Binyam; Dugas, Martin

    2015-03-01

    Electronic medical record (EMR) systems have the potential of supporting clinical work by providing the right information at the right time to the right people and thus make efficient use of resources. This is especially important in low-resource settings where reliable data are also needed to support public health and local supporting organizations. In this systematic literature review, our objectives are to identify and collect literature about success criteria of EMR implementations in low-resource settings and to summarize them into recommendations. Our search strategy relied on PubMed queries and manual bibliography reviews. Studies were included if EMR implementations in low-resource settings were described. The extracted success criteria and measurements were summarized into 7 categories: ethical, financial, functionality, organizational, political, technical, and training. We collected 381 success criteria with 229 measurements from 47 articles out of 223 articles. Most papers were evaluations or lessons learned from African countries, published from 1999 to 2013. Almost half of the EMR systems served a specific disease area like human immunodeficiency virus (HIV). The majority of criteria that were reported dealt with the functionality, followed by organizational issues, and technical infrastructures. Sufficient training and skilled personnel were mentioned in roughly 10%. Political, ethical, and financial considerations did not play a predominant role. More evaluations based on reliable frameworks are needed. Highly reliable data handling methods, human resources and effective project management, as well as technical architecture and infrastructure are all key factors for successful EMR implementation. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Impact of Knowledge Resources Linked to an Electronic Health Record on Frequency of Unnecessary Tests and Treatments

    Science.gov (United States)

    Goodman, Kenneth; Grad, Roland; Pluye, Pierre; Nowacki, Amy; Hickner, John

    2012-01-01

    Introduction: Electronic knowledge resources have the potential to rapidly provide answers to clinicians' questions. We sought to determine clinicians' reasons for searching these resources, the rate of finding relevant information, and the perceived clinical impact of the information they retrieved. Methods: We asked general internists, family…

  10. Resource conservation approached with an appropriate collection and upgrade-remanufacturing for used electronic products.

    Science.gov (United States)

    Zlamparet, Gabriel I; Tan, Quanyin; Stevels, A B; Li, Jinhui

    2018-03-01

    This comparative research represents an example for a better conservation of resources by reducing the amount of waste (kg) and providing it more value under the umbrella of remanufacturing. The three discussed cases will expose three issues already addressed separately in the literature. The generation of waste electrical and electronic equipment (WEEE) interacts with the environmental depletion. In this article, we gave the examples of addressed issues under the concept of remanufacturing. Online collection opportunity eliminating classical collection, a business to business (B2B) implementation for remanufactured servers and medical devices. The material reuse (recycling), component sustainability, reuse (part harvesting), product reuse (after repair/remanufacturing) indicates the recovery potential using remanufacturing tool for a better conservation of resources adding more value to the products. Our findings can provide an overview of new system organization for the general collection, market potential and the technological advantages using remanufacturing instead of recycling of WEEE or used electrical and electronic equipment. Copyright © 2017. Published by Elsevier Ltd.

  11. Adsorption and thermodynamic studies of Cu(II) and Zn(II) on organofunctionalized-kaolinite

    International Nuclear Information System (INIS)

    Guerra, Denis Lima; Airoldi, Claudio; Sousa, Kaline S. de

    2008-01-01

    Kaolinite-bearing clay samples from Perus, Sao Paulo state, Brazil, were used for chemical modification process with dimethyl sulfoxide and organofunctionalized with the silyating agent (RO) 3 Si(CH 2 ) 3 NH(CH 2 ) 2 NH 2 in the present study. The resulting material and natural kaolinite were subjected adsorpion process with Cu(II) and Zn(II) from aqueous solution at pH 6.0 and controlated temperature of 298 K. The Langmuir adsorption isotherm model has been applied to fit the experimental data. The results showed that the chemical modification process increases the basal spacing of the natural kaolinite from 0.711 to 0.955 nm. The energetic effects caused by Cu(II) and Zn(II) interactions were determined through calorimetric titration at the solid-liquid interface and gave a net thermal effect that enabled the calculation of the exothermic values and the equilibrium constant

  12. Surface complexation modeling of Cu(II adsorption on mixtures of hydrous ferric oxide and kaolinite

    Directory of Open Access Journals (Sweden)

    Schaller Melinda S

    2008-09-01

    Full Text Available Abstract Background The application of surface complexation models (SCMs to natural sediments and soils is hindered by a lack of consistent models and data for large suites of metals and minerals of interest. Furthermore, the surface complexation approach has mostly been developed and tested for single solid systems. Few studies have extended the SCM approach to systems containing multiple solids. Results Cu adsorption was measured on pure hydrous ferric oxide (HFO, pure kaolinite (from two sources and in systems containing mixtures of HFO and kaolinite over a wide range of pH, ionic strength, sorbate/sorbent ratios and, for the mixed solid systems, using a range of kaolinite/HFO ratios. Cu adsorption data measured for the HFO and kaolinite systems was used to derive diffuse layer surface complexation models (DLMs describing Cu adsorption. Cu adsorption on HFO is reasonably well described using a 1-site or 2-site DLM. Adsorption of Cu on kaolinite could be described using a simple 1-site DLM with formation of a monodentate Cu complex on a variable charge surface site. However, for consistency with models derived for weaker sorbing cations, a 2-site DLM with a variable charge and a permanent charge site was also developed. Conclusion Component additivity predictions of speciation in mixed mineral systems based on DLM parameters derived for the pure mineral systems were in good agreement with measured data. Discrepancies between the model predictions and measured data were similar to those observed for the calibrated pure mineral systems. The results suggest that quantifying specific interactions between HFO and kaolinite in speciation models may not be necessary. However, before the component additivity approach can be applied to natural sediments and soils, the effects of aging must be further studied and methods must be developed to estimate reactive surface areas of solid constituents in natural samples.

  13. Electronic theses and dissertations: a review of this valuable resource for nurse scholars worldwide.

    Science.gov (United States)

    Goodfellow, L M

    2009-06-01

    A worldwide repository of electronic theses and dissertations (ETDs) could provide worldwide access to the most up-to-date research generated by masters and doctoral students. Until that international repository is established, it is possible to access some of these valuable knowledge resources. ETDs provide a technologically advanced medium with endless multimedia capabilities that far exceed the print and bound copies of theses and dissertations housed traditionally in individual university libraries. CURRENT USE: A growing trend exists for universities worldwide to require graduate students to submit theses or dissertations as electronic documents. However, nurse scholars underutilize ETDs, as evidenced by perusing bibliographic citation lists in many of the research journals. ETDs can be searched for and retrieved through several digital resources such as the Networked Digital Library of Theses and Dissertations (http://www.ndltd.org), ProQuest Dissertations and Theses (http://www.umi.com), the Australasian Digital Theses Program (http://adt.caul.edu.au/) and through individual university web sites and online catalogues. An international repository of ETDs benefits the community of nurse scholars in many ways. The ability to access recent graduate students' research electronically from anywhere in the world is advantageous. For scholars residing in developing countries, access to these ETDs may prove to be even more valuable. In some cases, ETDs are not available for worldwide access and can only be accessed through the university library from which the student graduated. Public access to university library ETD collections is not always permitted. Nurse scholars from both developing and developed countries could benefit from ETDs.

  14. Adsorption of pesticides onto quartz, calcite, kaolinite, and α-alumina

    DEFF Research Database (Denmark)

    Clausen, Liselotte; Fabricius, Ida Lykke; Madsen, L.

    2001-01-01

    adsorption characteristics of selected pesticides. Investigated mineral phases included quartz, calcite, kaolinite, and alpha -alumina. Selected pesticides comprised atrazine (6-chloro-N-2-ethyl-N-4-isopropyl-1,3,5-triazine-2,4-diamine isoproturon [3-(4-isopropyl-phenyl)-1,1-dimethylurea)], mecoprop [(RS)-2...... due to formation of Ca-pesticide-surface complexes. Adsorption of the uncharged pesticides (atrazine and isoproturon) was detected only on kaolinite. The lack of adsorption on alpha -alumina indicates that the uncharged pesticides have a greater affinity for the silanol surface sites (= SiOH) than...

  15. Flotation of kaolinite from tailings of kaolin-washing plants by cationic collectors

    Directory of Open Access Journals (Sweden)

    Barani Kianoush

    2016-01-01

    Full Text Available Traditional processing of kaolin is achieved by dispersion of the mined ore and classification by means of multistage hydrocyclones. The inefficiencies inherent to cyclones produce a middling product that is commonly disposed back to the quarry. In this research recovery of kaolinite from tailings of the Zonoupz kaolin washing plant, which is located in Iran, was investigated by cationic flotation. Flotation experiments showed that flotation of kaolinite from tailings was much better in an acidic than in an alkaline medium containing cationic collectors.

  16. From Millennium ERM to Proquest 360 Resource Manager: Implementing a new Electronic Resources Management System ERMS in an International Graduate Research University in Saudi Arabia

    KAUST Repository

    Ramli, Rindra M.

    2017-05-17

    An overview of the Recommendation Study and the subsequent Implementation of a new Electronic Resources Management system ERMS in an international graduate research university in the Kingdom of Saudi Arabia. It covers the timeline, deliverables and challenges as well as lessons learnt by the Project Team.

  17. Effect of water on methane adsorption on the kaolinite (0 0 1) surface based on molecular simulations

    Science.gov (United States)

    Zhang, Bin; Kang, Jianting; Kang, Tianhe

    2018-05-01

    CH4 adsorption isotherms of kaolinite with moisture contents ranging from 0 to 5 wt% water, the effects of water on maximum adsorption capacity, kaolinite swelling, and radial distribution function were modelled by the implementing combined Monte Carlo (MC) and molecular dynamics (MD) simulations at 293.15 K (20 °C) and a pressure range of 1-20 MPa. The simulation results showed that the absolute adsorption of CH4 on both dry and moist kaolinite followed a Langmuir isotherm within the simulated pressure range, and both the adsorption capacity and the rate of CH4 adsorption decreased with the water content increases. The adsorption isosteric heats of CH4 on kaolinite decreased linearly with increasing water content, indicating that at higher water contents, the interaction energy between the CH4 and kaolinite was weaker. The interaction between kaolinite and water dominates and was the main contributing factor to kaolinite clay swelling. Water molecules were preferentially adsorbed onto oxygen and hydrogen atoms in kaolinite, while methane showed a tendency to be adsorbed only onto oxygen. The simulation results of our study provide the quantitative analysis of effect of water on CH4 adsorption capacity, adsorption rate, and interaction energy from a microscopic perspective. We hope that our study will contribute to the development of strategies for the further exploration of coal bed methane and shale gas.

  18. Electronic tracking of human resource skills and knowledge, just in time training, manageable due diligence

    Energy Technology Data Exchange (ETDEWEB)

    Kolodziej, M.A. [Quick Test International Inc., (Canada). Canadian Technology Human Resource Board; Baker, O. [KeySpan Energy Canada, Calgary, AB (Canada)

    2001-06-01

    KeySpan Energy Canada is in the process of obtaining recognition of various occupational profiles including pipeline operators, inspectors, and field and plant operators from various certifying organizations. The process of allowing individuals to obtain certification is recognized by Canadian Technology Human Resources Board as a step towards national standards for technologists and technicians. Proven competency is a must for workers in todays oil industry in response to increasingly stringent government safety regulations, environmental concerns and high public scrutiny. Quick Test international Inc. has developed a management tool in collaboration with end users at KeySpan Energy Canada. It is an electronic, Internet based competency tool for tracking personal competencies and maintaining continued competency. Response to the tool has been favourable. 2 refs., 4 figs.

  19. Modification of kaolinite surfaces through mechanochemical activation with quartz: A diffuse reflectance infrared fourier transform and chemometrics study.

    Science.gov (United States)

    Carmody, Onuma; Frost, Ray L; Kristóf, János; Kokot, Serge; Kloprogge, J Theo; Makó, Eva

    2006-12-01

    Studies of kaolinite surfaces are of industrial importance. One useful method for studying the changes in kaolinite surface properties is to apply chemometric analyses to the kaolinite surface infrared spectra. A comparison is made between the mechanochemical activation of Kiralyhegy kaolinites with significant amounts of natural quartz and the mechanochemical activation of Zettlitz kaolinite with added quartz. Diffuse reflectance infrared Fourier transform (DRIFT) spectra were analyzed using principal component analysis (PCA) and multi-criteria decision making (MCDM) methods, the preference ranking organization method for enrichment evaluations (PROMETHEE) and geometrical analysis for interactive assistance (GAIA). The clear discrimination of the Kiralyhegy spectral objects on the two PC scores plots (400-800 and 800-2030 cm(-1)) indicated the dominance of quartz. Importantly, no ordering of any spectral objects appeared to be related to grinding time in the PC plots of these spectral regions. Thus, neither the kaolinite nor the quartz are systematically responsive to grinding time according to the spectral criteria investigated. The third spectral region (2600-3800 cm(-1), OH vibrations), showed apparent systematic ordering of the Kiralyhegy and, to a lesser extent, Zettlitz spectral objects with grinding time. This was attributed to the effect of the natural quartz on the delamination of kaolinite and the accompanying phenomena (i.e., formation of kaolinite spheres and water). The mechanochemical activation of kaolinite and quartz, through dry grinding, results in changes to the surface structure. Different grinding times were adopted to study the rate of destruction of the kaolinite and quartz structures. This relationship (i.e., grinding time) was classified using PROMETHEE and GAIA methodology.

  20. Availability, Use and Constraints to Use of Electronic Information Resources by Postgraduates Students at the University of Ibadan

    Directory of Open Access Journals (Sweden)

    Dare Samuel Adeleke

    2017-12-01

    Full Text Available Availability, awareness and use of electronic resources provide access to authoritative, reliable, accurate and timely access to information. The use of electronic information resources (EIRs can enable innovation in teaching and increase timeliness in research of postgraduate students which will eventual result into encouragement of the expected research-led enquiry in this digital age. The study adopted a descriptive survey design. Samples of 300 of postgraduate students within seven out 13 Faculties were randomly selected. Data were collected using questionnaire designed to elicit response from respondents and data were analyzed using descriptive statistics methods percentages, mean, and standard deviation. Results indicated that internet was ranked most available and used in the university. Low level of usage of electronic resources, in particular, full texts data bases is linked to a number of constraints: Interrupted power supply was ranked highest among other factors as speed and capacity of computers, retrieval of records with high recall and low precision, retrieving records relevant to information need, lack of knowledge of search techniques to retrieve information effectively, non possession of requisite IT skills and problems accessing the internet. The study recommended that usage of electronic resources be made compulsory, intensifying awareness campaigns concerning the availability, training on use of electronic resources and the problem of power outage be addressed.

  1. Using mobile electronic devices to deliver educational resources in developing countries.

    Science.gov (United States)

    Mazal, Jonathan Robert; Ludwig, Rebecca

    2015-01-01

    Developing countries have far fewer trained radiography professionals than developed countries, which exacerbates the limited access to imaging services. The lack of trained radiographers reflects, in part, limited availability of radiographer-specific educational resources. Historically, organizations that provided such resources in the developing world faced challenges related to the limited stock of current materials as well as expenses associated with shipping and delivery. Four mobile electronic devices (MEDs) were loaded with educational content (e-books, PDFs, and digital applications) spanning major radiography topics. The MEDs were distributed to 4 imaging departments in Ghana, India, Nepal, and Nigeria based on evidence of need for radiography-specific resources, as revealed by survey responses. A cost comparison of postal delivery vs digital delivery of educational content was performed. The effectiveness of delivering additional content via Wi-Fi transmission also was evaluated. Feedback was solicited on users' experience with the MEDs as a delivery tool for educational content. An initial average per e-book expense of $30.05, which included the cost of the device, was calculated for the MED delivery method compared with $15.56 for postal delivery of printed materials. The cost of the MED delivery method was reduced to an average of $10.05 for subsequent e-book deliveries. Additional content was successfully delivered via Wi-Fi transmission to all recipients during the 3-month follow-up period. Overall user feedback on the experience was positive, and ideas for enhancing the MED-based method were identified. Using MEDs to deliver radiography-specific educational content appears to be more cost effective than postal delivery of printed materials on a long-term basis. MEDs are more efficient for providing updates to educational materials. Customization of content to department needs, and using projector devices could enhance the usefulness of MEDs for

  2. Effect of kaolinite and Ca-montmorillonite on the alleviation of soil water repellency

    Czech Academy of Sciences Publication Activity Database

    Dlapa, P.; Doerr, S. H.; Lichner, Ľ.; Šír, Miloslav; Tesař, Miroslav

    2004-01-01

    Roč. 50, č. 8 (2004), s. 358-363 ISSN 0370-663X R&D Projects: GA AV ČR IAA3042301; GA AV ČR IBS2060104 Keywords : water repellency * kaolinite * Ca-montmorillonite Subject RIV: DA - Hydrology ; Limnology Impact factor: 0.379, year: 2004

  3. Effect of composition and physical properties of. natural kaolinitic clays on their strong acid weathering rates

    Czech Academy of Sciences Publication Activity Database

    Hradil, David; Hostomský, Jiří

    2002-01-01

    Roč. 49, 1-2 (2002), s. 171-181 ISSN 0341-8162 R&D Projects: GA ČR GA203/98/P203 Institutional research plan: CEZ:AV0Z4032918 Keywords : kaolinite * illite * dissolution Subject RIV: CA - Inorganic Chemistry Impact factor: 1.035, year: 2002

  4. Microstructure, Interaction Mechanisms, and Stability of Binary Systems Containing Goethite and Kaolinite

    NARCIS (Netherlands)

    Wei, S.Y.; Tan, W.F.; Zhao, W.; Yu, Y.T.; Liu, F.; Koopal, L.K.

    2012-01-01

    Goethite and kaolinite are ubiquitous in natural environments. In soils they are often cemented together as a binary association, which has a significant influence on the structure and properties of soils. In this study, the mineralogy (using X-ray diffraction [XRD], thermal analyses, and infrared

  5. Mean residence time of soil organic matter associated with kaolinite and smectite

    NARCIS (Netherlands)

    Wattel-Koekkoek, E.J.W.; Buurman, P.; Plicht, van der J.; Wattel, J.T.; Breemen, van N.

    2003-01-01

    To gain insight into the effect of clay mineralogy on the turnover of organic matter, we analysed the C-14 activity of soil organic matter associated with clay in soils dominated by kaolinite and smectite in natural savanna systems in seven countries. Assuming that carbon inputs and outputs are in

  6. Mean residence time of soil organic matter associated with kaolinite and smectite

    NARCIS (Netherlands)

    Wattel-Koekkoek, E.J.W.; Buurman, P.; Plicht, J. van der; Wattel, E.; Breemen, N. van

    To gain insight into the effect of clay mineralogy on the turnover of organic matter, we analysed the C-14 activity of soil organic matter associated with clay in soils dominated by kaolinite and smectite in natural savanna systems in seven countries. Assuming that carbon inputs and outputs are in

  7. The Influence of Temperature on Kaolinite Fired Clay- Cement Materials Used as Disposal of Radioactive Waste

    International Nuclear Information System (INIS)

    El-Dakroury, A.

    2008-01-01

    The decay of encapsulated radioactive nuclides may cause elevation of the temperature in the waste form. Cement has been used for immobilization of low and intermediated level radioactive waste. The unstable component of concrete is the ordinary Portland cement (OPC). This study aimed to investigate experimentally the change occurring in the compressive strength and physico- chemical properties of ordinary Portland cement (OPC) matrices in comparable with other matrices which (OPC) were partially substituted by 0, 10, 20 and 30% of thermally-activated kaolinite clay by weight (the kaolinite clay activated by firing at 750 degree C for 5 hr then quenched by tap water). If all matrices mentioned before, are being exposed to the treatment temperature were varied from 100 degree C to 600 degree C by increment of 100 degree C for period of 3 hr without any load. The phase composition was performed by mean of differential thermal analysis and X-R-D. The results show that the replacements of (OPC) by 20 wt % thermal-activated Kaolinite clay improve the compressive properties by 30 %. The results of this investigation cleared that the recrystallization and carbonation of Ca(OH) 2 ; they also show a deformation of C-H-S and C 4 Ah 13 phases, besides the matrices have more stable resistance at 600 degree C. Meanwhile, this new immobilization matrix 20 % by wt thermally activated Kaolinite - clay showed the lowest leaching rate of simulated radioactive waste of Sr or Cs compared to the ordinary Portland cement (OPC) matrix

  8. The electronic encapsulation of knowledge in hydraulics, hydrology and water resources

    Science.gov (United States)

    Abbott, Michael B.

    The rapidly developing practice of encapsulating knowledge in electronic media is shown to lead necessarily to the restructuring of the knowledge itself. The consequences of this for hydraulics, hydrology and more general water-resources management are investigated in particular relation to current process-simulation, real-time control and advice-serving systems. The generic properties of the electronic knowledge encapsulator are described, and attention is drawn to the manner in which knowledge 'goes into hiding' through encapsulation. This property is traced in the simple situations of pure mathesis and in the more complex situations of taxinomia using one example each from hydraulics and hydrology. The consequences for systems architectures are explained, pointing to the need for multi-agent architectures for ecological modelling and for more general hydroinformatics systems also. The relevance of these developments is indicated by reference to ongoing projects in which they are currently being realised. In conclusion, some more general epistemological aspects are considered within the same context. As this contribution is so much concerned with the processes of signification and communication, it has been partly shaped by the theory of semiotics, as popularised by Eco ( A Theory of Semiotics, Indiana University, Bloomington, 1977).

  9. Plastics disassembly versus bulk recycling: engineering design for end-of-life electronics resource recovery.

    Science.gov (United States)

    Rios, Pedro; Stuart, Julie Ann; Grant, Ed

    2003-12-01

    Annual plastic flows through the business and consumer electronics manufacturing supply chain include nearly 3 billion lb of high-value engineering plastics derived from petroleum. The recovery of resource value from this stream presents critical challenges in areas of materials identification and recycling process design that demand new green engineering technologies applied together with life cycle assessment and ecological supply chain analysis to create viable plastics-to-plastics supply cycles. The sustainable recovery of potentially high-value engineering plastics streams requires that recyclers either avoid mixing plastic parts or purify later by separating smaller plastic pieces created in volume reduction (shredding) steps. Identification and separation constitute significant barriers in the plastics-to-plastics recycling value proposition. In the present work, we develop a model that accepts randomly arriving electronic products to study scenarios by which a recycler might identify and separate high-value engineering plastics as well as metals. Using discrete eventsimulation,we compare current mixed plastics recovery with spectrochemical plastic resin identification and subsequent sorting. Our results show that limited disassembly with whole-part identification can produce substantial yields in separated streams of recovered engineering thermoplastics. We find that disassembly with identification does not constitute a bottleneck, but rather, with relatively few workers, can be configured to pull the process and thus decrease maximum staging space requirements.

  10. Theoretical investigation of lead vapor adsorption on kaolinite surfaces with DFT calculations

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xinye [Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096 (China); Huang, Yaji, E-mail: heyyj@seu.edu.cn [Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096 (China); Pan, Zhigang [College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009 (China); Wang, Yongxing; Liu, Changqi [Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096 (China)

    2015-09-15

    Highlights: • Al surface after dehydroxylation is active while Si surface is inert. • The active sites are the unsaturated Al atoms and O atoms losing H atom. • PbO is the most suitable species for adsorption. • Increasing the activities of Al atoms can enhance the performance of kaolinite. • Produce of amorphous silica is a potential path to enhance the performance of kaolinite. - Abstract: Kaolinite can be used as the in-furnace sorbent/additive to adsorb lead (Pb) vapor at high temperature. In this paper, the adsorptions of Pb atom, PbO molecule and PbCl{sub 2} molecule on kaolinie surfaces were investigated by density functional theory (DFT) calculation. Si surface is inert to Pb vapor adsorption while Al surfaces with dehydroxylation are active for the unsaturated Al atoms and the O atoms losing H atoms. The adsorption energy of PbO is much higher than that of Pb atom and PbCl{sub 2}. Considering the energy barriers, it is easy for PbO and PbCl{sub 2} to adsorb on Al surfaces but difficult to escape. The high energy barriers of de–HCl process cause the difficulties of PbCl{sub 2} to form PbO·Al{sub 2}O{sub 3}·2SiO{sub 2} with kaolinite. Considering the inertia of Si atoms and the activity of Al atoms after dehydroxylation, calcination, acid/alkali treatment and some other treatment aiming at amorphous silica producing and Al activity enhancement can be used as the modification measures to improve the performance of kaolinite as the in-furnace metal capture sorbent.

  11. SAGES: a suite of freely-available software tools for electronic disease surveillance in resource-limited settings.

    Directory of Open Access Journals (Sweden)

    Sheri L Lewis

    Full Text Available Public health surveillance is undergoing a revolution driven by advances in the field of information technology. Many countries have experienced vast improvements in the collection, ingestion, analysis, visualization, and dissemination of public health data. Resource-limited countries have lagged behind due to challenges in information technology infrastructure, public health resources, and the costs of proprietary software. The Suite for Automated Global Electronic bioSurveillance (SAGES is a collection of modular, flexible, freely-available software tools for electronic disease surveillance in resource-limited settings. One or more SAGES tools may be used in concert with existing surveillance applications or the SAGES tools may be used en masse for an end-to-end biosurveillance capability. This flexibility allows for the development of an inexpensive, customized, and sustainable disease surveillance system. The ability to rapidly assess anomalous disease activity may lead to more efficient use of limited resources and better compliance with World Health Organization International Health Regulations.

  12. Electronic Human Resources Management (e-HRM Adoption Studies: Past and Future Research

    Directory of Open Access Journals (Sweden)

    Winarto Winarto

    2018-05-01

    Full Text Available Electronic human resource management (e-HRM systems become more widely used by profit and non-profit organization. However, the field currently lacks sound theoretical frameworks that can be useful in addressing a key issue concerning the implementation of e-HRM systems, in particular to obtain a better understanding of the factors influencing the adoption of e-HRM systems. The objective of this paper is to provide a foundation towards the development of a theoretical framework for the implementation of e-HRM systems and develop a conceptual model that would reflect the nature of e-HRM systems’ adoption through systematic literature review. Adopting Crossan and Apaydin’s procedure of systematic review, this paper investigated 21 empirical papers of electronics human resources management, then categorized them into 4 characteristics which influence the adoption; System and technology characteristics; Organizational characteristics; User/individual characteristics, and Environmental and contextual characteristics. Finally, the e-HRM adoption research framework is drawn and based on the framework; avenues for future research are discussed.   Bahasa Indonesia Abstrak: Manajemen sumber daya manusia elektronik (selanjutnya disebut dengan e-HRM semakin banyak digunakan oleh organisasi profit dan nonprofit. Namun, bidang dan topik ini belum memiliki kerangka teori yang mapan, yang dapat digunakan untuk menganalisis isu-isu terkait penerapan e-HRM, terutama mengenai faktor-faktor yang mempengaruhi adopsi sistem e-HRM. Tujuan penelitian ini adalah untuk memberikan landasan bagi pengembangan kerangka teoritis untuk implementasi sistem e-HRM dan mengembangkan model konseptual yang akan menggambarkan adopsi sistem e-HRM melalui tinjauan literatur sistematis. Mengadopsi prosedur dan metode Crossan dan Apaydin untuk melakukan telaah literatur secara sistematis, paper ini menyelidiki 21 publikasi empiris manajemen sumber daya manusia elektronik dari 2

  13. Comparative EXAFS study of uranium(VI) and neptunium(V) sorption onto kaolinite

    International Nuclear Information System (INIS)

    Reich, T.; Amayri, S.; Reich, Ta.; Jermolajev, J.

    2005-01-01

    Full text of publication follows: We investigated the surface sorption process of U(VI) and Np(V) on kaolinite by extended X-ray absorption fine structure (EXAFS) spectroscopy in the 10 μM concentration range. Batch experiments with kaolinite in CO 2 -equilibrated systems showed that the adsorption edge of U(VI) occurs at pH 5.5, i.e., near the pH PZC of kaolinite. The adsorption edge of Np(V) occurs well above the pH PZC value at pH 8.5. This may indicate that the bonds between Np(V) and the surface functional groups of kaolinite are not as strong as in the case of U(VI). U(VI) and Np(V) have in common that the amount which is adsorbed decreases when the pH is increased beyond the absorption maximum. This behavior can be attributed to the formation of U(VI) and Np(V) carbonato complexes in the aqueous solutions. The aim of this comparative EXAFS study was to investigate the reason for the different affinities of U(VI) and Np(V) for kaolinite by measuring their local environments at the clay surface. Samples were prepared from 4 g/L kaolinite, 0.1 M NaClO 4 , pH 3.0 - 10.5, presence and absence of ambient CO 2 . The U L 3 - and Np L 2 -edge EXAFS spectra of the wet paste samples were measured at room temperature in fluorescence mode at the Rossendorf Beamline (ROBL) at the European Synchrotron Radiation Facility. The measured U-O and U-Al/Si distances indicate inner-sphere sorption of U(VI) on kaolinite. There was no evidence of uranium neighbors in the EXAFS spectra, suggesting that the adsorbed U(VI) complexes were predominantly monomeric. The average distance between uranium and its equatorial oxygen atoms, O eq , increased from 2.32 to 2.38 Angstrom in the presence of atmospheric CO 2 when the pH was increased from 5.0 to 8.5. In the CO 2 -free system, the U-O eq distance was independent from pH and equal to 2.32 Angstrom. The lengthening of the average U-O eq distance in the presence of carbonate (or bicarbonate) suggests the formation of ternary U

  14. Preparation of Composite Hydrogel Based on Polyacrylamide and the Effect of Kaolinite on Its Properties in the Reservoir Conditions

    OpenAIRE

    Farhad Salimi; Mohsen Vafaie; Mehdi Razzaghi Kashani; Majid Rafipoor

    2013-01-01

    A gel composite (based on polyacrylamide and crosslinker Cr(III) acetate) was prepared by solvent method (distillate and water formation) and nanoclay particle (kaolinite). Using XRD tests, d001 was evaluated for kaolinite nanoparticles in gel composite. Kaolinite modification using dimethyl-sulfoxide led to increase interlamellar spacing from 7.21 to 10.82 o A. Based on the results obtained for samples prepared from unmodified clay besides the pure clay, there is a wide peak at 2θ = 8o; whic...

  15. Impact of Electronic Resources and Usage in Academic Libraries in Ghana: Evidence from Koforidua Polytechnic & All Nations University College, Ghana

    Science.gov (United States)

    Akussah, Maxwell; Asante, Edward; Adu-Sarkodee, Rosemary

    2015-01-01

    The study investigates the relationship between impact of electronic resources and its usage in academic libraries in Ghana: evidence from Koforidua Polytechnic & All Nations University College, Ghana. The study was a quantitative approach using questionnaire to gather data and information. A valid response rate of 58.5% was assumed. SPSS…

  16. Utilization of Electronic Information Resources by Undergraduate Students of University of Ibadan: A Case Study of Social Sciences and Education

    Science.gov (United States)

    Owolabi, Sola; Idowu, Oluwafemi A.; Okocha, Foluke; Ogundare, Atinuke Omotayo

    2016-01-01

    The study evaluated utilization of electronic information resources by undergraduates in the Faculties of Education and the Social Sciences in University of Ibadan. The study adopted a descriptive survey design with a study population of 1872 undergraduates in the Faculties of Education and the Social Sciences in University of Ibadan, from which a…

  17. Systematic review of electronic surveillance of infectious diseases with emphasis on antimicrobial resistance surveillance in resource-limited settings.

    Science.gov (United States)

    Rattanaumpawan, Pinyo; Boonyasiri, Adhiratha; Vong, Sirenda; Thamlikitkul, Visanu

    2018-02-01

    Electronic surveillance of infectious diseases involves rapidly collecting, collating, and analyzing vast amounts of data from interrelated multiple databases. Although many developed countries have invested in electronic surveillance for infectious diseases, the system still presents a challenge for resource-limited health care settings. We conducted a systematic review by performing a comprehensive literature search on MEDLINE (January 2000-December 2015) to identify studies relevant to electronic surveillance of infectious diseases. Study characteristics and results were extracted and systematically reviewed by 3 infectious disease physicians. A total of 110 studies were included. Most surveillance systems were developed and implemented in high-income countries; less than one-quarter were conducted in low-or middle-income countries. Information technologies can be used to facilitate the process of obtaining laboratory, clinical, and pharmacologic data for the surveillance of infectious diseases, including antimicrobial resistance (AMR) infections. These novel systems require greater resources; however, we found that using electronic surveillance systems could result in shorter times to detect targeted infectious diseases and improvement of data collection. This study highlights a lack of resources in areas where an effective, rapid surveillance system is most needed. The availability of information technology for the electronic surveillance of infectious diseases, including AMR infections, will facilitate the prevention and containment of such emerging infectious diseases. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  18. Comparison of electrodialytic removal of Cu from spiked kaolinite, spiked soil and industrially polluted soil

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Lepkova, Katarina; Kubal, Martin

    2006-01-01

    Electrokinetic remediation methods for removal of heavy metals from polluted soils have been subjected for quite intense research during the past years since these methods are well suitable for fine-grained soils where other remediation methods fail. Electrodialytic remediation is an electrokinetic...... remediation method which is based on applying an electric DC field and the use of ion exchange membranes that ensures the main transport of heavy metals to be out of the pollutes soil. An experimental investigation was made with electrodialytic removal of Cu from spiked kaolinite, spiked soil and industrially...... polluted soil under the same operational conditions (constant current density 0.2 mA/cm2 and duration 28 days). The results of the present paper show that caution must be taken when generalising results obtained in spiked kaolinite to remediation of industrially polluted soils, as it was shown...

  19. Adsorption behavior of strontium on binary mineral mixtures of Montmorillonite and Kaolinite

    Energy Technology Data Exchange (ETDEWEB)

    Bascetin, Elvan [Cekmece Nuclear Research and Training Center, P.K.1 34149, Atatuerk Airport, Istanbul (Turkey); Atun, Guelten [Engineering Faculty, Chemistry Department, Istanbul University, 34850 Avcilar, Istanbul (Turkey)]. E-mail: gultena@istanbul.edu.tr

    2006-08-15

    The adsorption behavior of kaolinite and montmorillonite minerals and their mixtures in respect of Sr ion were studied by means of a batch method using {sup 90}Sr as a radio tracer. The effect of several parameters such as temperature, pH, Sr concentration and supporting electrolyte were investigated. Experimentally measured distribution coefficients showed a good agreement to within 98.5-99.7% with theoretically calculated values. The values of adsorption capacity of adsorbents and mean adsorption energy of adsorption were calculated by fitting the adsorption data to Dubinin-Radushkevich isotherm. The adsorption capacity of clay mixtures decreased as kaolinite fractions increased. The mean adsorption energy values of 8.0-9.5 kJ mol{sup -1} showed that adsorption was governed by ion exchange. The Freundlich parameters were used to characterize a site distribution function for binary exchange between Sr and Na.

  20. Adsorption behavior of strontium on binary mineral mixtures of Montmorillonite and Kaolinite

    International Nuclear Information System (INIS)

    Bascetin, Elvan; Atun, Guelten

    2006-01-01

    The adsorption behavior of kaolinite and montmorillonite minerals and their mixtures in respect of Sr ion were studied by means of a batch method using 90 Sr as a radio tracer. The effect of several parameters such as temperature, pH, Sr concentration and supporting electrolyte were investigated. Experimentally measured distribution coefficients showed a good agreement to within 98.5-99.7% with theoretically calculated values. The values of adsorption capacity of adsorbents and mean adsorption energy of adsorption were calculated by fitting the adsorption data to Dubinin-Radushkevich isotherm. The adsorption capacity of clay mixtures decreased as kaolinite fractions increased. The mean adsorption energy values of 8.0-9.5 kJ mol -1 showed that adsorption was governed by ion exchange. The Freundlich parameters were used to characterize a site distribution function for binary exchange between Sr and Na

  1. The Use of Electronic Resources by Academic Staff at the University of Ilorin, Nigeria

    Science.gov (United States)

    Tella, Adeyinka; Orim, Faith; Ibrahim, Dauda Morenikeji; Memudu, Suleiman Ajala

    2018-01-01

    The use of e-resources is now commonplace among academics in tertiary educational institutions the world over. Many academics including those in the universities are exploring the opportunities of e-resources to facilitate teaching and research. As the use of e-resources is increasing particularly among academics at the University of Ilorin,…

  2. Modeling antecedents of electronic medical record system implementation success in low-resource setting hospitals.

    Science.gov (United States)

    Tilahun, Binyam; Fritz, Fleur

    2015-08-01

    With the increasing implementation of Electronic Medical Record Systems (EMR) in developing countries, there is a growing need to identify antecedents of EMR success to measure and predict the level of adoption before costly implementation. However, less evidence is available about EMR success in the context of low-resource setting implementations. Therefore, this study aims to fill this gap by examining the constructs and relationships of the widely used DeLone and MacLean (D&M) information system success model to determine whether it can be applied to measure EMR success in those settings. A quantitative cross sectional study design using self-administered questionnaires was used to collect data from 384 health professionals working in five governmental hospitals in Ethiopia. The hospitals use a comprehensive EMR system since three years. Descriptive and structural equation modeling methods were applied to describe and validate the extent of relationship of constructs and mediating effects. The findings of the structural equation modeling shows that system quality has significant influence on EMR use (β = 0.32, P quality has significant influence on EMR use (β = 0.44, P service quality has strong significant influence on EMR use (β = 0.36, P effect of EMR use on user satisfaction was not significant. Both EMR use and user satisfaction have significant influence on perceived net-benefit (β = 0.31, P mediating factor in the relationship between service quality and EMR use (P effect on perceived net-benefit of health professionals. EMR implementers and managers in developing countries are in urgent need of implementation models to design proper implementation strategies. In this study, the constructs and relationships depicted in the updated D&M model were found to be applicable to assess the success of EMR in low resource settings. Additionally, computer literacy was found to be a mediating factor in EMR use and user satisfaction of

  3. Effect of glutamic acid on copper sorption onto kaolinite. Batch experiments and surface complexation modeling

    Energy Technology Data Exchange (ETDEWEB)

    Karimzadeh, Lotfallah; Barthen, Robert; Gruendig, Marion; Franke, Karsten; Lippmann-Pipke, Johanna [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Reactive Transport; Stockmann, Madlen [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes

    2017-06-01

    In this work, we study the mobility behavior of Cu(II) under conditions related to an alternative, neutrophile biohydrometallurgical Cu(II) leaching approach. Sorption of copper onto kaolinite influenced by glutamic acid (Glu) was investigated in the presence of 0.01 M NaClO{sub 4} by means of binary and ternary batch adsorption measurements over a pH range of 4 to 9 and surface complexation modeling.

  4. Effects of brief milling and acid treatment on two ordered and disordered kaolinite structures

    Czech Academy of Sciences Publication Activity Database

    Valášková, M.; Barabaszová, K.; Hundáková, M.; Ritz, M.; Plevová, Eva

    2011-01-01

    Roč. 54, č. 1 (2011), s. 70-76 ISSN 0169-1317 R&D Projects: GA ČR GA105/08/1398 Grant - others:GA ČR(CZ) GA205/09/0352 Institutional research plan: CEZ:AV0Z30860518 Keywords : kaolinite * milling * hydrochloric acid Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.474, year: 2011 http://www.sciencedirect.com/science/article/pii/S0169131711002675

  5. Effect of glutamic acid on copper sorption onto kaolinite. Batch experiments and surface complexation modeling

    International Nuclear Information System (INIS)

    Karimzadeh, Lotfallah; Barthen, Robert; Gruendig, Marion; Franke, Karsten; Lippmann-Pipke, Johanna; Stockmann, Madlen

    2017-01-01

    In this work, we study the mobility behavior of Cu(II) under conditions related to an alternative, neutrophile biohydrometallurgical Cu(II) leaching approach. Sorption of copper onto kaolinite influenced by glutamic acid (Glu) was investigated in the presence of 0.01 M NaClO_4 by means of binary and ternary batch adsorption measurements over a pH range of 4 to 9 and surface complexation modeling.

  6. Kaolinite adsorption-regeneration system for dyestuff treatment by Fenton based processes.

    Science.gov (United States)

    Rosales, Emilio; Anasie, Delia; Pazos, Marta; Lazar, Iuliana; Sanromán, M Angeles

    2018-05-01

    The regeneration and reuse of adsorbents is a subject of interest nowadays in order to reduce the pollution and the wastes generated in the adsorption wastewater treatment. In this work, the regeneration of the spent kaolinite by different advanced oxidation processes (Fenton, electro-Fenton and electrokinetic-Fenton) was evaluated. Initially, it was confirmed the ability of a low cost clayey material, kaolinite, for the adsorption of model dye such as Rhodamine B showing Freundlich isotherm fitting. Then, the regeneration and consequent degradation of the pollutant in the adsorbent by Fenton based processes was carried out. The role of different parameters affecting the regeneration process (H 2 O 2 :Fe 2+ ratio, liquid:solid ratio) were evaluated. Working at 100:1 H 2 O 2 :Fe 2+ ratio and 30min near complete dye removal (around 97%) from kaolinite was obtained by Fenton treatment. After that, a two-stage treatment for adsorption-regeneration was evaluated during five treatment cycles demonstrating its viability for regeneration of the adsorbent through dye degradation. Based on the successful application of Fenton technique, the improvement of the treatment by electro-Fenton and electrokinetic-Fenton were studied for different solid:liquid ratios achieving satisfactory regeneration values. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Chemial Bond and Stability of Adsorption of[Au(AsS3)]2- on the Surface of Kaolinite

    Institute of Scientific and Technical Information of China (English)

    MIN Xin-min; CHEN Yun; HONG Han-lie

    2004-01-01

    Density function theory and discrete variation method (DFT-DVM) were used to study the adsorption of [Au(AsS3 ) ]2- on the surface of kaolinite. The correlation among structure, chemical bond and stability was discussed. Several models were selected with [ Au( AsS3 ) ]2- in different directions and sites. The resultsshow that the models with gold on the edge of kaolinite basal layer contain pincerlike bond among gold and severaloxygen atoms and form strong Au - O covalent bond, so these models are more stable than those with gold aboveor under the layer. The models with gold near to [ AlO2(OH)4 ] octahedra are more stable than those with goldnear to the vacancy without aluminium. These two stable tendencies in kaolinite- [ Au( AsS3 ) ]2- are stronger thanthat in kaolinite-Au systems. The interaction between [ Au( AsS3 ) ]2- and kaolinite is stronger than that betweengold and kaolinite, and this interaction is strong enough to form the surface complexes.

  8. Probing adsorption of polyacrylamide-based polymers on anisotropic Basal planes of kaolinite using quartz crystal microbalance.

    Science.gov (United States)

    Alagha, Lana; Wang, Shengqun; Yan, Lujie; Xu, Zhenghe; Masliyah, Jacob

    2013-03-26

    Quartz crystal microbalance with dissipation (QCM-D) was applied to investigate the adsorption characteristics of polyacrylamide-based polymers (PAMs) on anisotropic basal planes of kaolinite. Kaolinite basal planes were differentiated by depositing kaolinite nanoparticles (KNPs) on silica and alumina sensors in solutions of controlled pH values. Adsorption of an in-house synthesized organic-inorganic Al(OH)3-PAM (Al-PAM) as an example of cationic hybrid PAM and a commercially available partially hydrolyzed polyacrylamide (MF1011) as an example of anionic PAM was studied. Cationic Al-PAM was found to adsorb irreversibly and preferentially on tetrahedral silica basal planes of kaolinite. In contrast, anionic MF1011 adsorbed strongly on aluminum-hydroxy basal planes, while its adsorption on tetrahedral silica basal planes was weak and reversible. Adsorption study revealed that both electrostatic attraction and hydrogen-bonding mechanisms contribute to adsorption of PAMs on kaolinite. The adsorbed Al-PAM layer was able to release trapped water overtime and became more compact, while MF1011 film became more dissipative as backbones stretched out from kaolinite surface with minimal overlapping. Experimental results obtained from this study provide clear insights into the phenomenon that governs flocculation-based solid-liquid separation processes using multicomponent flocculants of anionic and cationic nature.

  9. Effect of polycarboxylate ether comb-type polymer on viscosity and interfacial properties of kaolinite clay suspensions.

    Science.gov (United States)

    Zhang, Ling; Lu, Qingye; Xu, Zhenghe; Liu, Qingxia; Zeng, Hongbo

    2012-07-15

    The interactions between kaolinite clay particles and a comb-type polymer (polycarboxylate ether or PCE), so-called PCE super-plasticizer, were investigated through viscosity and surface forces measurements by a rheometer and a Surface Forces Apparatus (SFA). The addition of PCE shows a strong impact on the viscosity of concentrated kaolinite suspensions in alkaline solutions (pH=8.3) but a weak effect under acidic conditions (pH=3.4). In acidic solutions, the high viscosity measured is attributed to the strong electrostatic interaction between negatively charged basal planes and positively charged edge surfaces of clay particles. Under the alkaline condition, the suspension viscosity was found to first increase significantly and then decrease with increasing PCE dosages. The results from surface forces measurement show that PCE molecules at low dosages can bridge the kaolinite particles in the concentrated suspensions via hydrogen bonding, leading to the formation of a kaolinite-PCE "network" and hence an increased suspension viscosity. At high PCE dosages, clay particles are fully covered by PCE molecules, leading to a more dispersed kaolinite suspensions and hence lower suspension viscosity due to steric repulsion between the adsorbed PCE molecules. The insights derived from measuring viscosity and interfacial properties of kaolinite suspensions containing varying amount of comb-type super-plasticizer PCE at different pH provide the foundation for many engineering applications and optimizing industrial processes. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Use and Cost of Electronic Resources in Central Library of Ferdowsi University Based on E-metrics

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Davarpanah

    2012-07-01

    Full Text Available The purpose of this study was to investigate the usage of electronic journals in Ferdowsi University, Iran based on e-metrics. The paper also aimed to emphasize the analysis of cost-benefit and the correlation between the journal impact factors and the usage data. In this study experiences of Ferdowsi University library on licensing and usage of electronic resources was evaluated by providing a cost-benefit analysis based on the cost and usage statistics of electronic resources. Vendor-provided data were also compared with local usage data. The usage data were collected by tracking web-based access locally, and by collecting vender-provided usage data. The data sources were one-year of vendor-supplied e-resource usage data such as Ebsco, Elsevier, Proquest, Emerald, Oxford and Springer and local usage data collected from the Ferdowsi university web server. The study found that actual usage values differ for vendor-provided data and local usage data. Elsevier has got the highest usage degree in searches, sessions and downloads. Statistics also showed that a small number of journals satisfy significant amount of use while the majority of journals were used less frequent and some were never used at all. The users preferred the PDF rather than HTML format. The data in subject profile suggested that the provided e-resources were best suited to certain subjects. There was no correlation between IF and electronic journal use. Monitoring the usage of e-resources gained increasing importance for acquisition policy and budget decisions. The article provided information about local metrics for the six surveyed vendors/publishers, e.g. usage trends, requests per package, cost per use as related to the scientific specialty of the university.

  11. Kaolinite-supported nanoscale zero-valent iron for removal of Pb2+ from aqueous solution: reactivity, characterization and mechanism.

    Science.gov (United States)

    Zhang, Xin; Lin, Shen; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

    2011-05-01

    The use of nanoscale zero-valent iron (nZVI) to remediate contaminated groundwater is limited due to its lack of durability and mechanical strength. To address this issue, 20% (w/w) nZVI was loaded onto kaolinite as a support material (K-nZVI). More than 96% of Pb(2+) was removed from aqueous solution using K-nZVI at an initial condition of 500 mg/L Pb(2+) within 30 min under the conditions of 10 g/L of K-nZVI, pH 5.10 and a temperature of 30 °C. To understand the mechanism of removal of Pb(2+), various techniques were implemented to characterize K-nZVI. Scanning electron microscopy (SEM) indicated that K-nZVI had a suitable dispersive state with a lower aggregation, where the mean specific surface area and average particle size as determined by the BET-N(2) method and X-ray diffraction (XRD), were 26.11 m(2)/g and 44.3 nm, respectively. The results obtained from XRD, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) indicated that a small number of iron oxides formed on the surface of K-nZVI, suggesting that free Pb(2+) was adsorbed onto K-nZVI and subsequently reduced to Pb(0). Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Use and User Perception of Electronic Information Resources: A Case Study of Siva Institute of Frontier Technology, India

    Directory of Open Access Journals (Sweden)

    Velmurugan Chandran

    2013-12-01

    Full Text Available The present study aims to explore the use and user perception of electronic resources in Siva Institute of Frontier Technology, India. A total number of 123 users were taken into account for the study through a questionnaire-based survey method. A well-structured questionnaire was designed and distributed to the selected 200 students and staff members. 123 copies of the questionnaires were returned dully filled in and the overall response rate was 61.50 percent. The questionnaire contained both open- and close-ended questions. The collected data were classified, analyzed, and tabulated by using simple statistical methods. This study covers the impact of electronic resources on students and faculty in their academic pursuit.

  13. Challenges in the implementation of an electronic surveillance system in a resource-limited setting: Alerta, in Peru

    Directory of Open Access Journals (Sweden)

    Soto Giselle

    2008-11-01

    Full Text Available Abstract Background Infectious disease surveillance is a primary public health function in resource-limited settings. In 2003, an electronic disease surveillance system (Alerta was established in the Peruvian Navy with support from the U.S. Naval Medical Research Center Detachment (NMRCD. Many challenges arose during the implementation process, and a variety of solutions were applied. The purpose of this paper is to identify and discuss these issues. Methods This is a retrospective description of the Alerta implementation. After a thoughtful evaluation according to the Centers for Disease Control and Prevention (CDC guidelines, the main challenges to implementation were identified and solutions were devised in the context of a resource-limited setting, Peru. Results After four years of operation, we have identified a number of challenges in implementing and operating this electronic disease surveillance system. These can be divided into the following categories: (1 issues with personnel and stakeholders; (2 issues with resources in a developing setting; (3 issues with processes involved in the collection of data and operation of the system; and (4 issues with organization at the central hub. Some of the challenges are unique to resource-limited settings, but many are applicable for any surveillance system. For each of these challenges, we developed feasible solutions that are discussed. Conclusion There are many challenges to overcome when implementing an electronic disease surveillance system, not only related to technology issues. A comprehensive approach is required for success, including: technical support, personnel management, effective training, and cultural sensitivity in order to assure the effective deployment of an electronic disease surveillance system.

  14. RESEARCH OF INFLUENCE OF QUALITY OF ELECTRONIC EDUCATIONAL RESOURCES ON QUALITY OF TRAINING WITH USE OF DISTANCE TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    H. M. Kravtsov

    2013-03-01

    Full Text Available Communication improving of educational processes requires today new approaches to the management arrangements and forming of educational policy in the field of distance learning, which is based on the use of modern information and communication technologies. An important step in this process is the continuous monitoring of the development and implementation of information technology and, in particular, the distance learning systems in higher educational establishments. The main objective of the monitoring is the impact assessment on the development of distance learning following the state educational standards, curricula, methodical and technical equipment and other factors; factors revelation that influence the implementation and outcomes of distance learning; results comparison of educational institution functioning and distance education systems in order to determine the most efficient ways of its development. The paper presents the analysis results of the dependence of the quality of educational services on the electronic educational resources. Trends in educational services development was studied by comparing the quality influence of electronic educational resources on the quality of educational services of higher pedagogical educational institutions of Ukraine as of 2009-2010 and 2012-2013. Generally, the analysis of the survey results allows evaluating quality of the modern education services as satisfactory and it can be said that almost 70% of the success of their future development depends on the quality of the used electronic educational resources and distance learning systems in particular.

  15. Tracking the Flow of Resources in Electronic Waste - The Case of End-of-Life Computer Hard Disk Drives.

    Science.gov (United States)

    Habib, Komal; Parajuly, Keshav; Wenzel, Henrik

    2015-10-20

    Recovery of resources, in particular, metals, from waste flows is widely seen as a prioritized option to reduce their potential supply constraints in the future. The current waste electrical and electronic equipment (WEEE) treatment system is more focused on bulk metals, where the recycling rate of specialty metals, such as rare earths, is negligible compared to their increasing use in modern products, such as electronics. This study investigates the challenges in recovering these resources in the existing WEEE treatment system. It is illustrated by following the material flows of resources in a conventional WEEE treatment plant in Denmark. Computer hard disk drives (HDDs) containing neodymium-iron-boron (NdFeB) magnets were selected as the case product for this experiment. The resulting output fractions were tracked until their final treatment in order to estimate the recovery potential of rare earth elements (REEs) and other resources contained in HDDs. The results further show that out of the 244 kg of HDDs treated, 212 kg comprising mainly of aluminum and steel can be finally recovered from the metallurgic process. The results further demonstrate the complete loss of REEs in the existing shredding-based WEEE treatment processes. Dismantling and separate processing of NdFeB magnets from their end-use products can be a more preferred option over shredding. However, it remains a technological and logistic challenge for the existing system.

  16. HELP (INFORMATION ELECTRONIC RESOURCE "CHRONICLE OF ONU: DATES, FACTS, EVENTS": HISTORY OF UNIVERSITY IN INFORMATION SPACE

    Directory of Open Access Journals (Sweden)

    А. М. Гавриленко

    2016-03-01

    Object of research is the help information resource "The chronicle of the Odessa national university of I. I. Mechnikov: dates, facts, events". The main objective of our article – to state the main methodological bases of creation of information resource. One of advantages of information resource is possibility of continuous updating and replenishment by new information. Main objective of creation of this information resource is systematization of material on stories of the Odessa national university of I. I. Mechnikov from the date of his basis to the present, ensuring interactive access to information on the main dates, the most significant events in life of university. The base of research are sources on the history of university, chronology of historical development, formation of infrastructure, cadres and scientific researches. In information resource the main stages of development, functioning and transformation of the Odessa University are analyzed, information on its divisions is collected. For creation of this information resource in Scientific library the method of work was developed, the main selection criteria of data are allocated. This information resource have practical value for all who is interested in history of university, historians, scientists-researchers of history of science and the city of Odessa.

  17. Print and Electronic Resources: Usage Statistics at Guru Gobind Singh Indraprastha University Library

    Science.gov (United States)

    Kapoor, Kanta

    2010-01-01

    Purpose: The purpose of this paper is to quantify the use of electronic journals in comparison with the print collections in the Guru Gobind Singh Indraprastha University Library. Design/methodology/approach: A detailed analysis was made of the use of lending services, the Xerox facility and usage of electronic journals such as Science Direct,…

  18. Understanding intention to use electronic information resources: A theoretical extension of the technology acceptance model (TAM).

    Science.gov (United States)

    Tao, Donghua

    2008-11-06

    This study extended the Technology Acceptance Model (TAM) by examining the roles of two aspects of e-resource characteristics, namely, information quality and system quality, in predicting public health students' intention to use e-resources for completing research paper assignments. Both focus groups and a questionnaire were used to collect data. Descriptive analysis, data screening, and Structural Equation Modeling (SEM) techniques were used for data analysis. The study found that perceived usefulness played a major role in determining students' intention to use e-resources. Perceived usefulness and perceived ease of use fully mediated the impact that information quality and system quality had on behavior intention. The research model enriches the existing technology acceptance literature by extending TAM. Representing two aspects of e-resource characteristics provides greater explanatory information for diagnosing problems of system design, development, and implementation.

  19. Uranium(VI) retention on quartz and kaolinite. Experiments and modelling

    International Nuclear Information System (INIS)

    Mignot, G.

    2001-01-01

    The behaviour of uranium in the geosphere is an important issue for safety performance assessment of nuclear waste repositories, or in the context of contaminated sites due to mining activity related to nuclear field. Under aerobic conditions, the fate of uranium is mainly governed by the ability of minerals to sorb U(VI) aqueous species. Hence, a thorough understanding of U(VI) sorption processes on minerals is required to provide a valuable prediction of U(VI) migration in the environment. In this study, we performed sorption/desorption experiments of U(VI) on quartz and kaolinite, for systems favouring the formation in solution (i) of UO 2 2+ and monomeric hydrolysis products or (ii) of di-/tri-meric uranyl aqueous species, and / or U(VI)-colloids or UO 2 (OH) 2 precipitates, or (iii) of uranyl-carbonate complexes. Particular attention was paid to determine the surface characteristics of the solids and their modification due to dissolution/precipitation processes during experiments. A double layer surface complexation model was applied to our experimental data in order to derive surface complexation equilibria and intrinsic constants which allow a valuable description of U(VI) retention over a wide range of pH, ionic strength, initial concentration of uranium [0.1-10μM] and solid - solution equilibration time. U(VI) sorption on quartz was successfully modeled by using two sets of adsorption equilibria, assuming (i) the formation of the surface complexes SiOUO 2 + , SiOUO 2 OH and SiO(UO 2 ) 3 (OH) 5 , or (ii) the formation of the mono-dentate complex SiO(UO 2 ) 3 (OH) 5 and of the bidentate complex (SiO) 2 UO 2 . Assumptions on the density of each type of surface sites of kaolinite and on their acid-base properties were made from potentiometric titrations of kaolinite suspensions. We proposed on such a basis a set of surface complexation equilibria which accounts for U(VI) uptake on kaolinite over a wide range of chemical conditions, with aluminol edge sites as

  20. Building and Managing Electronic Resources in Digital Era in India with Special Reference to IUCAA and NIV, Pune: A Comparative Case Study

    Science.gov (United States)

    Sahu, H. K.; Singh, S. N.

    2015-04-01

    This paper discusses and presents a comparative case study of two libraries in Pune, India, Inter-University Centre for Astronomy and Astrophysics and Information Centre and Library of National Institute of Virology (Indian Council of Medical Research). It compares how both libraries have managed their e-resource collections, including acquisitions, subscriptions, and consortia arrangements, while also developing a collection of their own resources, including pre-prints and publications, video lectures, and other materials in an institutional repository. This study illustrates how difficult it is to manage electronic resources in a developing country like India, even though electronic resources are used more than print resources. Electronic resource management can be daunting, but with a systematic approach, various problems can be solved, and use of the materials will be enhanced.

  1. The level of the usage of the human resource information system and electronic recruitment in Croatian companies

    Directory of Open Access Journals (Sweden)

    Snježana Pivac

    2014-12-01

    Full Text Available Performing business according to contemporary requirements influences companies for continuous usage of modern managerial tools, such as a human resource information system (HRIS and electronic recruitment (ER. Human resources have been recognised as curtail resources and the main source of a competitive advantage in creation of successful business performance. In order to attract and select the top employees, companies use quality information software for attracting internal ones, and electronic recruitment for attracting the best possible external candidates. The main aim of this paper is to research the level of the usage of HRIS and ER within medium-size and large Croatian companies. Moreover, the additional aim of this paper is to evaluate the relationship among the usage of these modern managerial tools and the overall success of human resource management within these companies. For the purpose of this paper, primary and secondary research has been conducted in order to reveal the level of the usage of HRIS and ER as well as the overall success of human resource management in Croatian companies. The companies’ classification (HRIS and ER is done by using the non-hierarchical k-means cluster method as well as the nonparametric Kruskal Wallis test. Further, the companies are ranked by the multicriteria PROMETHEE method. Relevant nonparametric tests are used for testing the overall companies’ HRM. Finally, binary logistic regression is estimated, relating binary variable HRM and HRIS development. After detailed research, it can be concluded that large Croatian companies apply HRIS in majority (with a positive relation to HRM performance, but still require certain degrees of its development.

  2. MendelWeb: An Electronic Science/Math/History Resource for the WWW.

    Science.gov (United States)

    Blumberg, Roger B.

    This paper describes a hypermedia resource, called MendelWeb that integrates elementary biology, discrete mathematics, and the history of science. MendelWeb is constructed from Gregor Menders 1865 paper, "Experiments in Plant Hybridization". An English translation of Mendel's paper, which is considered to mark the birth of classical and…

  3. Helping Patrons Find Locally Held Electronic Resources: An Interlibrary Loan Perspective

    Science.gov (United States)

    Johnston, Pamela

    2016-01-01

    The University of North Texas Libraries provide extensive online access to academic journals through major vendor databases. As illustrated by interlibrary loan borrowing requests for items held in our databases, patrons often have difficulty navigating the available resources. In this study, the Interlibrary Loan staff used data gathered from the…

  4. QR Codes as Finding Aides: Linking Electronic and Print Library Resources

    Science.gov (United States)

    Kane, Danielle; Schneidewind, Jeff

    2011-01-01

    As part of a focused, methodical, and evaluative approach to emerging technologies, QR codes are one of many new technologies being used by the UC Irvine Libraries. QR codes provide simple connections between print and virtual resources. In summer 2010, a small task force began to investigate how QR codes could be used to provide information and…

  5. Surface characteristics of kaolinite and other selected 2-layer silicate minerals

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.D.; Nalaskowski, J.; Abdul, B.; Du, H. [Utah Univ., Salt Lake City, UT (United States). Dept. of Metallurgical Engineering

    2007-10-15

    The wetting of mineral phases by bitumens plays an important role in efficient bitumen recovery. In this study, molecular dynamics simulations were used to investigate the electrokinetic behaviour and interfacial water features of 2-layer silicate minerals. The study compared the planar structures of antigorite and kaolinite with equivalent tubular structures of halloysite and chrysolite. Equivalency of pH dependency of zeta potential was determined using electrophoretic mobility measurements. The atomic mismatch between tetrahydral and octahydral sheets in a bilayer was examined in order to determine electrokinetic behaviour. Results of the study indicated that the silica tetrahydral surface was not wetted by water, but by structural imperfections. Polarity reversal within a tetrahedral octahedral layer and an out-of-order layer within the stack were then considered to explain both the wetting characteristics and electrokinetic behaviour. It was concluded that further research is needed to explain why the hexagonal rings structure for the silica tetrahydral face of kaolinite is wetted by water. 55 refs., 2 tabs., 12 figs.

  6. Effects of Organic Acids on Adsorption of Cadmium onto Kaolinite, Goethite, and Bayerite

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Effects of organic acids (oxalic, acetic, and citric) on adsorption characteristics of Cadmium (Cd) on soil clay minerals(kaolinite, goethite, and bayerite) were studied under different concentrations and different pH values. Although the types of organic acids and minerals were different, the effects of the organic acids on the adsorption of Cd on the minerals were similar, i.e., the amount of adsorbed Cd with an initial solution pH of 5.0 and initial Cd concentration of 35 mg L-1increased with increasing concentration of the organic acid in solution at lower concentrations, and decreased at higher concentrations. The percentage of Cd adsorbed on the minerals in the presence of the organic acids increased considerably with increasing pH of the solution. Meanwhile, different Cd adsorption in the presence of the organic acids, due to different properties on both organic acids and clay minerals, on kaolinite, goethite, or bayerite for different pHs or organic acid concentrations was found.

  7. Obtention of the cation exchange capacity of a natural kaolinite with radioactive tracers

    International Nuclear Information System (INIS)

    Uribe I, A.; Badillo A, V.E.; Monroy G, F.

    2005-01-01

    One of the more used techniques for the elimination of the heavy metals present in water systems is to use adsorbent mineral phases like zeolites and clays, among others. The clays are able to exchange easily the fixed ions in the external surface of its crystals or well the ions present in the interlaminar spaces of the structures, for other existent ones in the encircling aqueous solutions for that the Cation exchange capacity (CIC) is defined as the sum of all the cations exchange that a mineral can possess independent to the physicochemical conditions. The CIC is equal to the measure of the total of negative charges of the mineral by mass of the solid (meq/g). In this investigation work, the value of the CIC equal to 2.5 meq/100 g is obtained, of a natural kaolinite from the State of Hidalgo studying the retention of the sodium in the kaolinite with the aid of the radioactive isotope 24 Na and of the selective electrodes technique, making vary the pH value. So is experimentally demonstrated that the CIC is an intrinsic property of the mineral independent of the pH value of the solution and of the charges origin. (Author)

  8. Effect of Cosolutes on the Sorption of Phenanthrene onto Mineral Surface of River Sediments and Kaolinite

    Directory of Open Access Journals (Sweden)

    Yinghong Wu

    2014-01-01

    Full Text Available Sorption of phenanthrene onto the natural sediment with low organic carbon content (OC%, organic-free sediment, and kaolinite was investigated through isotherm experiments. Effects of cosolutes (pyrene, 4-n-nonyphenol (NP, and humic acid (HA on phenanthrene sorption were also studied by comparing apparent solid-water distribution coefficients (Kdapp of phenanthrene. Two addition sequences, including “cosolute added prior to phenanthrene” and “cosolute and phenanthrene added simultaneously,” were adopted. The Freundlich model fits phenanthrene sorption on all 3 sorbents well. The sorption coefficients on these sorbents were similar, suggesting that mineral surface plays an important role in the sorption of hydrophobic organic contaminants on low OC% sediments. Cosolutes could affect phenanthrene sorption on the sorbents, which depended on their properties, concentrations, and addition sequences. Pyrene inhibited phenanthrene sorption. Sorbed NP inhibited phenanthrene sorption at low levels and promoted sorption at high levels. Similar to NP, effect of HA on phenanthrene sorption onto the natural sediment depended on its concentrations, whereas, for the organic-free sediment and kaolinite, preloading of HA at high levels led to an enhancement in phenanthrene Kdapp while no obvious effect was observed at low HA levels; dissolved HA could inhibit phenanthrene sorption on the two sorbents.

  9. Effect of polyvinylpyrrolidone and sodium lauroyl isethionate on kaolinite suspension in an aqueous phase.

    Science.gov (United States)

    Kwan, Chang-Chin; Chu, Wen-Hweu; Shimabayashi, Saburo

    2006-08-01

    Suspension of concentrated kaolinite (20 g/30 ml-medium) in the presence of polyvinylpyrrolidone (PVP) and sodium lauroyl isethionate (SLI) was allowed to evaluate its degree of dispersion based on their rheological studies. Flow curves at low shear rate, measured by means of cone-plate method, showed a non-Newtonian flow. Plastic viscosity and Bingham yield value were derived from the flow curves. Relative viscosity, effective volume fraction and void fraction of secondary particle were also obtained. Results of dispersity and fluidity of the suspension were explained. PVP acted as a flocculant at a concentration lower than 0.1% but as a dispersant at a higher concentration. The presence of SLI could decrease both the Bingham yield value and suspension viscosity. Cooperative and competitive effects of PVP and SLI were found. Results indicated that SLI enhanced the degree of dispersion of kaolinite when PVP was less than 0.1%. The suspension, however, showed a maximum flocculation (i.e., aggregation) at 4 mM SLI when the concentration of PVP was higher than 0.1%.

  10. Crystallization of aqueous ammonium sulfate particles internally mixed with soot and kaolinite: crystallization relative humidities and nucleation rates.

    Science.gov (United States)

    Pant, Atul; Parsons, Matthew T; Bertram, Allan K

    2006-07-20

    Using optical microscopy, we investigated the crystallization of aqueous ammonium sulfate droplets containing soot and kaolinite, as well as the crystallization of aqueous ammonium sulfate droplets free of solid material. Our results show that soot did not influence the crystallization RH of aqueous ammonium sulfate particles under our experimental conditions. In contrast, kaolinite increased the crystallization RH of the aqueous ammonium sulfate droplets by approximately 10%. In addition, our results show that the crystallization RH of aqueous ammonium sulfate droplets free of solid material does not depend strongly on particle size. This is consistent with conclusions made previously in the literature, based on comparisons of results from different laboratories. From the crystallization results we determined the homogeneous nucleation rates of crystalline ammonium sulfate in aqueous ammonium sulfate droplets and the heterogeneous nucleation rates of crystalline ammonium sulfate in aqueous ammonium sulfate particles containing kaolinite. Using classical nucleation theory and our experimental data, we determined that the interfacial tension between an ammonium sulfate critical nucleus and an aqueous ammonium sulfate solution is 0.064 +/- 0.003 J m(-2) (in agreement with our previous measurements), and the contact angle between an ammonium sulfate critical nucleus and a kaolinite surface is 59 +/- 2 degrees. On the basis of our results, we argue that soot will not influence the crystallization RH of aqueous ammonium sulfate droplets in the atmosphere, but kaolinite can significantly modify the crystallization RH of atmospheric ammonium sulfate droplets. As an example, the CRH50 (the relative humidity at which 50% of the droplets crystallize) ranges from about 41 to 51% RH when the diameter of the kaolinite inclusion ranges from 0.1 to 5 microm. For comparison, the CRH50 of aqueous ammonium sulfate droplets (0.5 microm diameter) free of solid material is

  11. Eavesdropping on Electronic Guidebooks: Observing Learning Resources in Shared Listening Environments.

    Science.gov (United States)

    Woodruff, Allison; Aoki, Paul M.; Grinter, Rebecca E.; Hurst, Amy; Szymanski, Margaret H.; Thornton, James D.

    This paper describes an electronic guidebook, "Sotto Voce," that enables visitors to share audio information by eavesdropping on each others guidebook activity. The first section discusses the design and implementation of the guidebook device, key aspects of its user interface, the design goals for the audio environment, the eavesdropping…

  12. Development and evolution of The Knowledge Hub for Pathology and related electronic resources.

    Science.gov (United States)

    Hardwick, David F; Sinard, John; Silva, Fred

    2011-06-01

    The Knowledge Hub for Pathology was created to provide authenticated and validated knowledge for United States and Canadian Academy of Pathology members and pathologists worldwide with access to the Web. Using the material presented at the annual meeting of the United States and Canadian Academy of Pathology with existing selection and review procedures ensured that these criteria were met without added costly procedures. Further submissions for courses and research papers are provided in electronic format and funded by universities and hospitals for their creation; thus, the principal costs borne by the United States and Canadian Academy of Pathology are Web site-posting costs. Use has escalated rapidly from 2 million hits in 2002 to 51 million in 2009 with use by 35,000 pathologists from now a total of 180 countries. This true "freemium" model is a successful process as are more traditional continuing professional development course structures such as Anatomic Pathology Electronic Case Series, a "premium" model for learning electronically also sponsored by the United States and Canadian Academy of Pathology. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. An Exploratory study on the use of LibAnswers to Resolve, Track and Monitor Electronic Resources Issues: The KAUST Library experience

    KAUST Repository

    Ramli, Rindra M.

    2017-01-01

    An Exploratory study on KAUST library use of LibAnswers in resolving electronic resources questions received in LibAnswers. It describes the findings of the questions received in LibAnswers. The author made suggestions based on the findings to improve the reference services in responding to e-resources questions.

  14. An Exploratory study on the use of LibAnswers to Resolve, Track and Monitor Electronic Resources Issues: The KAUST Library experience

    KAUST Repository

    Ramli, Rindra M.

    2017-05-03

    An Exploratory study on KAUST library use of LibAnswers in resolving electronic resources questions received in LibAnswers. It describes the findings of the questions received in LibAnswers. The author made suggestions based on the findings to improve the reference services in responding to e-resources questions.

  15. Designing a model of electronic human resource management’s implementation at the Ministry of Communications and Information Technology

    Directory of Open Access Journals (Sweden)

    Mirali Seyednaghavi

    2017-06-01

    Full Text Available : In the first phase of this study a model for electronic human resource management in government agencies based on new public services was explored by using software MAXQDA, then in the second phase, relationship between the elements of the theory were tested using software Smart PLS2. So the aim of this study is to design a model of electronic human resource management’s implementation at the Ministry of Communications and Information Technology. In this regard, according to Strauss and Corbin’s structured plan, five hypotheses were tested. Quantitative data analysis indicates that the pressures of the policies and global perspectives cause to move toward e-HRM. Among the contextual conditions macro structural mechanisms, considerations of actors, governance considerations have a significant impact on the strategy of new public services and therefore lead to the consequences of its implementation in public organizations. The findings suggest that e-HRM does not have a positive and meaningful impact on new public services, and in our country, although the recent political developments have somehow removed the gap between public policy makers, administrators, and the public, but there is still a long way to go.

  16. Preference and Use of Electronic Information and Resources by Blind/Visually Impaired in NCR Libraries in India

    Directory of Open Access Journals (Sweden)

    Shailendra Kumar

    2013-06-01

    Full Text Available This paper aims to determine the preference and use of electronic information and resources by blind/visually impaired users in the leading National Capital Region (NCR libraries of India. Survey methodology has been used as the basic research tool for data collection with the help of questionnaires. The 125 in total users surveyed in all the five libraries were selected randomly on the basis of willingness of the users with experience of working in digital environments to participate in the survey. The survey results were tabulated and analyzed with descriptive statistics methods using Excel software and 'Stata version 11'. The findings reveal that ICT have a positive impact in the lives of people with disabilities as it helps them to work independently and increases the level of confidence among them. The Internet is the most preferred medium of access to information among the majority of blind/visually impaired users. The 'Complexity of content available on the net' is found as the major challenge faced during Internet use by blind users of NCR libraries. 'Audio books on CDs/DVDs and DAISY books' are the most preferred electronic resources among the majority of blind/visually impaired users. This study will help the library professionals and organizations/institutions serving people with disabilities to develop effective library services for blind/visually impaired users in the digital environment on the basis of findings on information usage behavior in the study.

  17. Internet and electronic resources for inflammatory bowel disease: a primer for providers and patients.

    Science.gov (United States)

    Fortinsky, Kyle J; Fournier, Marc R; Benchimol, Eric I

    2012-06-01

    Patients with inflammatory bowel disease (IBD) are increasingly turning to the Internet to research their condition and engage in discourse on their experiences. This has resulted in new dynamics in the relationship between providers and their patients, with misinformation and advertising potentially presenting barriers to the cooperative patient-provider partnership. This article addresses important issues of online IBD-related health information and social media activity, such as quality, reliability, objectivity, and privacy. We reviewed the medical literature on the quality of online information provided to IBD patients, and summarized the most commonly accessed Websites related to IBD. We also assessed the activity on popular social media sites (such as Facebook, Twitter, and YouTube), and evaluated currently available applications for use by IBD patients and providers on mobile phones and tablets. Through our review of the literature and currently available resources, we developed a list of recommended online resources to strengthen patient participation in their care by providing reliable, comprehensive educational material. Copyright © 2011 Crohn's & Colitis Foundation of America, Inc.

  18. The immersion freezing behavior of size-segregated soot and kaolinite particles

    Science.gov (United States)

    Hartmann, S.; Augustin, S.; Clauss, T.; Niedermeier, D.; Raddatz, M.; Wex, H.; Shaw, R. A.; Stratmann, F.

    2011-12-01

    Heterogeneous ice nucleation plays a crucial role for ice formation in mixed-phase and cirrus clouds and has an important impact on precipitation formation, global radiation balances, and therefore Earth's climate (Cantrell and Heymsfield, 2005). Mineral dust and soot particles are found to be a major component of ice crystal residues (e.g., Pratt et al., 2009) so these substances are potential sources of atmospheric ice nuclei (IN). Experimental studies investigating the immersion freezing behavior of size-segregated soot and kaolinite particles conducted at the Leipzig Aerosol Cloud Interaction Simulator (LACIS) are presented. In our measurements only one aerosol particle is immersed in an air suspended water droplet which can trigger ice nucleation. The method facilitates very precise examinations with respect to temperature, ice nucleation time and ice nucleus size. Considering laboratory studies, the picture of the IN ability of soot particles is quite heterogeneous. Our studies show that submicron flame, spark soot particles and optionally coated with sulfuric acid to simulate chemically aging do not act as IN at temperatures higher than homogeneous freezing taking place. Therefore soot particles might not be an important source of IN for immersion freezing in the atmosphere. In contrast, kaolinite being representative for natural mineral dust with a well known composition and structure is found to be very active in forming ice for all freezing modes (e.g., Mason and Maybank, 1958). Analyzing the immersion freezing behavior of different sized kaolinite particles (300, 500 and 700 nm in diameter) the size effect was clearly observed, i.e. the ice fraction (number of frozen droplets per total number) scales with particle surface, i.e. the larger the ice nucleus surface the higher the ice fraction. The slope of the logarithm of the ice fraction as function of temperature is similar for all particle sizes investigated and fits very well with the results of L

  19. Characterization of Sr2+ uptake on natural minerals of kaolinite and magnesite using XRPD, SEM/EDS, XPS, and DRIFT

    International Nuclear Information System (INIS)

    Shahwan, T.; Erten, H.N.

    2005-01-01

    The sorption behavior of Sr 2+ ions on natural minerals rich in kaolinite and magnesite was studied using SEM/EDS, XPS, XRPD, AAS/AES and DRIFT techniques. Quantitative analysis of the XPS data shows that magnesite is more effective in Sr 2+ uptake than kaolinite. DRIFT spectra and XRPD patterns indicate that the structures of both minerals were not affected upon Sr 2+ sorption. Intercalation of DMSO in kaolinite lamellae aiming at increasing the interlayer space did not significantly enhance the sorption capacity of the clay towards Sr 2+ probably due to the lack of a negative charge on the accessible sites. EDS mapping indicated that while the sorbed Sr is equally distributed on surface of natural kaolinite, it was associated - to a larger extent - with the regions richer in Mg in the case of natural magnesite. Comparing the uptake mechanisms of natural magnesite with that of pure MgCO 3 , it was seen that while natural magnesite sorbed Sr 2+ mainly through an ion exchange type mechanism, the formation of SrCO 3 coprecipitate was detected on the surface of the MgCO 3 at higher loadings. (orig.)

  20. Kinetics and Thermodynamics of Sorption of 4-Nitrophenol on Activated Kaolinitic Clay and Jatropha Curcas Activated Carbon from Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Samsudeen Olanrewaju Azeez

    2016-06-01

    Full Text Available Adsorption behaviour of 4-nitrophenol (4-NP on activated kaolinitic clay and Jatropha curcas activated carbon was investigated. The kaolinitic clay and Jatropha curcas were activated with 1 M HNO3 and 0.5 M NaOH respectively and were characterized by XRF, XRD, BET, SEM and FTIR techniques. The effects of processing parameters, such as initial 4-NP concentration, temperature, pH, contact time and adsorbent dosage on the adsorption process were investigated. The results obtained showed that Jatropha curcas activated carbon exhibited higher performance than activated kaolinitic clay for the removal of 4-nitrophenol from aqueous solution. Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models were used to describe the adsorption isotherms. The adsorption data were best fitted with Freundlich model. The experimental data of the two adsorbate-adsorbent systems fitted very well with the pseudo-second order kinetic model with r2 values of 0.999 respectively. Adsorption thermodynamic parameters were also estimated. The results revealed that the adsorption of 4-nitrophenol onto both adsorbents were exothermic processes and spontaneous for Jatropha curcas activated carbon but non spontaneous for activated kaolinitic clay.

  1. Kinetics and thermodynamics of sorption of 4-nitrophenol on activated kaolinitic clay and jatropha curcas activated carbon from aqueous solution

    International Nuclear Information System (INIS)

    Azeez, S.O.; Adekola, F.A.

    2016-01-01

    Adsorption behaviour of 4-nitrophenol (4-NP) on activated kaolinitic clay and Jatropha curcas activated carbon was investigated. The kaolinitic clay and Jatropha curcas were activated with 1 M HNO/sub 3/ and 0.5 M NaOH respectively and were characterized by XRF, XRD, BET, SEM and FTIR techniques. The effects of processing parameters, such as initial 4-NP concentration, temperature, pH, contact time and adsorbent dosage on the adsorption process were investigated. The results obtained showed that Jatropha curcas activated carbon exhibited higher performance than activated kaolinitic clay for the removal of 4-nitrophenol from aqueous solution. Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models were used to describe the adsorption isotherms. The adsorption data were best fitted with Freundlich model. The experimental data of the two adsorbate-adsorbent systems fitted very well with the pseudosecond order kinetic model with r2 values of 0.999 respectively. Adsorption thermodynamic parameters were also estimated. The results revealed that the adsorption of 4-nitrophenol onto both adsorbents were exothermic processes and spontaneous for Jatropha curcas activated carbon but non spontaneous for activated kaolinitic clay. (author)

  2. Sorption of triclosan onto activated carbon, kaolinite and montmorillonite: effects of pH, ionic strength, and humic acid.

    Science.gov (United States)

    Behera, Shishir Kumar; Oh, Seok-Young; Park, Hung-Suck

    2010-07-15

    Sorption of triclosan on three sorbents, viz., activated carbon, kaolinite and montmorillonite was studied as a function of pH, ionic strength and humic acid (HA) concentration through controlled batch experiments. Triclosan sorption was found to be higher in the acidic pH range, as varying pH showed significant influence on the surface charge of the sorbents and degree of ionization of the sorbate. Sorption capacity of the sorbents increased with an increase in the ionic strength of solution. At low pH (pH 3), the overall increase in triclosan sorption was 1.2, approximately 4 and 3.5 times, respectively for activated carbon, kaolinite and montmorillonite when ionic strength was increased from 1x10(-3) to 5x10(-1) M. Triclosan sorption onto activated carbon decreased from 31.4 to 10.6 mg g(-1) by increasing the HA concentration to 200 mg C L(-1). However, during sorption onto kaolinite and montmorillonite, the effect of HA was very complex probably due to (i) hydrophobicity (log K(ow)=4.76) of triclosan; and (ii) complexation of HA with triclosan. Though triclosan sorption onto activated carbon is higher, the potential of kaolinite and montmorillonite in controlling the transport of triclosan in subsurface environment can still be appreciable. 2010 Elsevier B.V. All rights reserved.

  3. U(VI) sorption on kaolinite. Effects of pH, U(VI) concentration and oxyanions

    International Nuclear Information System (INIS)

    Liang Gao; Ziqian Yang; Keliang Shi; Xuefeng Wang; Zhijun Guo; Wangsuo Wu

    2010-01-01

    U(VI) sorption on kaolinite was studied as functions of contact time, pH, U(VI) concentration, solid-to-liquid ratio (m/V) by using a batch experimental method. The effects of sulfate and phosphate on U(VI) sorption were also investigated. It was found that the sorption kinetics of U(VI) can be described by a pseudo-second-order model. Potentiometric titrations at variable ionic strengths indicated that the titration curves of kaolinite were not sensitive to ionic strength, and that the pH of the zero net proton charge (pH PZNPC ) was at 6.9. The sorption of U(VI) on kaolinite increased with pH up to 6.5 and reached a plateau at pH >6.5. The presence of phosphate strongly increased U(VI) sorption especially at pH <5.5, which may be due to formation of ternary surface complexes involving phosphate. In contrast, the presence of sulfate did not cause any apparent effect on U(VI) sorption. A double layer model was used to interpret both results of potentiometric titrations and U(VI) sorption on kaolinite. (author)

  4. Structure of kaolinite and influence of stacking faults: reconciling theory and experiment using inelastic neutron scattering analysis.

    Science.gov (United States)

    White, Claire E; Kearley, Gordon J; Provis, John L; Riley, Daniel P

    2013-05-21

    The structure of kaolinite at the atomic level, including the effect of stacking faults, is investigated using inelastic neutron scattering (INS) spectroscopy and density functional theory (DFT) calculations. The vibrational dynamics of the standard crystal structure of kaolinite, calculated using DFT (VASP) with normal mode analysis, gives good agreement with the experimental INS data except for distinct discrepancies, especially for the low frequency modes (200-400 cm(-1)). By generating several types of stacking faults (shifts in the a,b plane for one kaolinite layer relative to the adjacent layer), it is seen that these low frequency modes are affected, specifically through the emergence of longer hydrogen bonds (O-H⋯O) in one of the models corresponding to a stacking fault of -0.3151a - 0.3151b. The small residual disagreement between observed and calculated INS is assigned to quantum effects (which are not taken into account in the DFT calculations), in the form of translational tunneling of the proton in the hydrogen bonds, which lead to a softening of the low frequency modes. DFT-based molecular dynamics simulations show that anharmonicity does not play an important role in the structural dynamics of kaolinite.

  5. Analysis and characterization of kaolinitic clay Rio Grande do Norte for use in refractory

    International Nuclear Information System (INIS)

    Medeiros, A.L.; Souza Junior, C.F.; Silva, C.L. Mendes da

    2011-01-01

    This work aims to characterize clays from the State of Rio Grande do Norte for use in the manufacture of refractory bricks. Initially, we analyzed the X-ray fluorescence and X-ray diffraction on samples of clay to obtain the components of the starting materials and their microstructures. The test samples were fabricated by uniaxial pressure of 20 MPa, and then were sintered between 1000 ° C and 1200 ° C, with a landing sintering for 1 hour. Tests including thermal shrinkage, water absorption and apparent porosity. Initial results of the analysis indicate the presence of clay minerals kaolinite, montmorillonite and muscovite, as well group minerals of quartz, dolomite, calcite and calcium silicate in the samples tested. (author)

  6. Adsorption of barium on kaolinite, illite and montmorillonite at various ionic strengths

    International Nuclear Information System (INIS)

    Atun, G.; Bascetin, E.

    2003-01-01

    The sorption behaviour of Ba 2+ in three different clay minerals from various regions of Turkey has been investigated by means of a tracer technique using 133 Ba in batch experiments. Sorption of Ba 2+ on montmorillonite, kaolinite and illite has been studied in mixed solutions of BaCl 2 and NaCl at ionic strengths ranging from 1 x 10 -3 M to 1 x 10 -1 M. The L-shape exchange isotherms for Ba 2+ -Na + systems are well defined by a Langmuir type equation. The exchange capacity of Ba 2+ ions for all three clay minerals increased with decreasing ionic strength. The adsorption data were fitted to a Freundlich isotherm and empirical Freundlich parameters enabled to the generation of a site distribution function. The selectivity coefficients were nearly constant at low Ba loading and decreased as loading increased. This behavior was an indication of an ion exchange process between Ba 2+ and Na + ions

  7. Adsorption of some heavy metals on sulphate and phosphate modified kaolinite clay

    International Nuclear Information System (INIS)

    Adebowale, K.O.; Unuabonah, I.E.; Olu-Owolabi, B.I.

    2003-12-01

    Kaolinite clay, in bright white lumps collected from from Ubulu-Ukwu, Delta State, Nigeria, was modified with 200μ.ml -1 of phosphate and sulphate anion and thereafter used to adsorb some heavy metals viz. lead (Pb), Cadmium (Cd), Zinc (Zn) and Copper (Cu) from aqueous solution of the metals. The metal ions showed the greatest affinity for the P-modified (P-mod) sorbents. The order of adsorption of P-mod follows the order: P-mod Pb > P-mod Cu > P-mod Zn > P-mod Cd . Desorption studies showed that the P-modified sorbents exhibited a very strong ability to specifically adsorb lead, copper and zinc and are therefore poorly desorbed. All the metals were easily desorbed from the unmodified sorbent. The potential of the modified sorbents are enumerated. (author)

  8. Physical attributes of kaolinitic and oxidic oxisols resulting from different usage systems

    Directory of Open Access Journals (Sweden)

    José Frederico Centurion

    2004-09-01

    Full Text Available The objective of this study was to assess the physical attributes of a kaolinitic oxisol, medium texture (Haplustox and an oxidic oxisol, clayey (Eutrustox under different usage systems, localized in the region of Jaboticabal, SP, Brazil. The usage systems were sugarcane, cotton and forest. Parameters such as soil bulk density, total porosity, macro and microporosity at the depths of 0.0-0.1; 0.1-0.2; 0.2-0.3, and 0.3-0.4 m were evaluated. Haplustox showed greater bulk density and smaller total porosity, macro and microporosity. The usage increased the bulk density in 0.0-0.3 m depth, with greater effects on the kaolinitic oxisol, mainly in 0.1-0.2 m depth in the areas cultivated with sugarcane.A mineralogia da fração argila e os sistemas de uso exercem fundamental importância na estrutura do solo. Assim, objetivou-se avaliar atributos físicos de um Latossolo Vermelho Distrófico, caulinítico (LVd, e, de um Latossolo Vermelho Eutroférrico, oxídico (LVef, sob diferentes sistemas de uso, localizados no município de Jaboticabal (SP, Brasil. Os sistemas de uso foram: cana-de-açúcar; algodão e mata. Foram avaliadas a densidade do solo, porosidade total, macro e microporosidade, nas profundidades de 0,0-0,1, 0,1-0,2, 0,2-0,3, 0,3-0,4 m. O Latossolo caulinítico (LVd apresentou maior densidade do solo e menor porosidade total, macro e microporosidade. O uso aumentou a densidade do solo na profundidade de 0,0-0,3 m, com efeitos maiores no Latossolo caulinítico, principalmente na profundidade de 0,1-0,2 m na área cultivada com cana-de-açúcar.

  9. Adsorption kinetics of maxilon yellow 4GL and maxilon red GRL dyes on kaolinite

    International Nuclear Information System (INIS)

    Dogan, Mehmet; Karaoglu, M. Hamdi; Alkan, Mahir

    2009-01-01

    Kaolinite, a low-costly material, is the most abundant phyllosilicate mineral in highly weathered soils. In this work, the adsorption kinetics of maxilon yellow 4GL (MY 4GL) and maxilon red GRL (MR GRL) dyes on kaolinite from aqueous solutions was investigated using the parameters such as contact time, stirring speed, initial dye concentration, initial pH, ionic strength, acid-activation, calcination and solution temperature. The equilibrium time was 150 min for both dyes. The results showed that alkaline pH was favorable for the adsorption of MY 4GL and MR GRL dyes and physisorption seemed to play a major role in the adsorption process. It was found that the rate of adsorption decreases with increasing temperature and the process is exothermic. The adsorption kinetics followed the pseudo-second-order equation for both dyes investigated in this work with the k 2 values lying in the region of 1.79 x 10 4 to 107.87 x 10 4 g/mol min for MY 4GL and 3.44 x 10 4 to 72.09 x 10 4 g/mol min for MR GRL. The diffusion coefficient values calculated for the dyes were in the range of 3.76 x 10 -9 to 62.50 x 10 -9 cm 2 /s for MY 4GL and 1.98 x 10 -9 to 44.00 x 10 -9 cm 2 /s for MR GRL, and are compatible with other studies reported in the literature. The thermodynamic activation parameters such as the enthalpy, entropy and free energy were determined. The obtained results confirmed the applicability of this clay as an efficient adsorbent for cationic dyes.

  10. Electronic medical records in diabetes consultations: participants' gaze as an interactional resource.

    Science.gov (United States)

    Rhodes, Penny; Small, Neil; Rowley, Emma; Langdon, Mark; Ariss, Steven; Wright, John

    2008-09-01

    Two routine consultations in primary care diabetes clinics are compared using extracts from video recordings of interactions between nurses and patients. The consultations were chosen to present different styles of interaction, in which the nurse's gaze was either primarily toward the computer screen or directed more toward the patient. Using conversation analysis, the ways in which nurses shift both gaze and body orientation between the computer screen and patient to influence the style, pace, content, and structure of the consultation were investigated. By examining the effects of different levels of engagement between the electronic medical record and the embodied patient in the consultation room, we argue for the need to consider the contingent nature of the interface of technology and the person in the consultation. Policy initiatives designed to deliver what is considered best-evidenced practice are modified in the micro context of the interactions of the consultation.

  11. Granulometric composition study of mineral resources using opto-electronic devices and Elsieve software system

    Directory of Open Access Journals (Sweden)

    Kaminski Stanislaw

    2016-01-01

    Full Text Available The use of mechanical sieves has a great impact on measurement results because occurrence of anisometric particles causes undercounting the average size. Such errors can be avoided by using opto-electronic measuring devices that enable measurement of particles from 10 μm up to a few dozen millimetres in size. The results of measurement of each particle size fraction are summed up proportionally to its weight with the use of Elsieve software system and for every type of material particle-size distribution can be obtained. The software allows further statistical interpretation of the results. Beam of infrared radiation identifies size of particles and counts them precisely. Every particle is represented by an electronic impulse proportional to its size. Measurement of particles in aqueous suspension that replaces the hydrometer method can be carried out by using the IPS L analyser (range from 0.2 to 600 μm. The IPS UA analyser (range from 0.5 to 2000 μm is designed for measurement in the air. An ultrasonic adapter enables performing measurements of moist and aggregated particles from 0.5 to 1000 μm. The construction and software system allow to determine second dimension of the particle, its shape coefficient and specific surface area. The AWK 3D analyser (range from 0.2 to 31.5 mm is devoted to measurement of various powdery materials with subsequent determination of particle shape. The AWK B analyser (range from 1 to 130 mm measures materials of thick granulation and shape of the grains. The presented method of measurement repeatedly accelerates and facilitates study of granulometric composition.

  12. Green Supply Chain Collaboration for Fashionable Consumer Electronics Products under Third-Party Power Intervention—A Resource Dependence Perspective

    Directory of Open Access Journals (Sweden)

    Jiuh-Biing Sheu

    2014-05-01

    Full Text Available Under third-party power intervention (TPPI, which increases uncertainty in task environments, complex channel power interplays and restructuring are indispensable among green supply chain members as they move toward sustainable collaborative relationships for increased viability and competitive advantage. From the resource dependence perspective, this work presents a novel conceptual model to investigate the influence of political and social power on channel power restructuring and induced green supply chain collaboration in brander-retailer bidirectional green supply chains of fashionable consumer electronics products (FCEPs. An FCEP refers to the consumer electronics product (e.g., personal computers, mobile phones, computer notebooks, and game consoles with the features of a well-known brand associated, a short product lifecycle, timely and fashionable design fit for market trends, and quick responsiveness to the variations of market demands. The proposed model is tested empirically using questionnaire data obtained from retailers in the FCEP brander-retailer distribution channels. Analytical results reveal that as an extension of political and social power, TPPI positively affects the reciprocal interdependence of dyadic members and reduces power asymmetry, thereby enhancing the collaborative relationship of dyadic members and leading to improved green supply chain performance. Therein, reciprocal interdependence underlying collaborative relationship is the key to reducing the external environmental uncertainties in the TPPI context.

  13. The management of online resources and long-term saving of electronic documents by transfer into the digital space

    Directory of Open Access Journals (Sweden)

    Marius Daniel MAREŞ

    2011-12-01

    The electronic archive refers to the electronic storage system, along with the totality of electronic-type stored documents, while using as storage support any environment that can support storing and from which an electronic document can be presented.

  14. Electro-osmosis in kaolinite with pH-dependent surface charge modelling by homogenization

    Directory of Open Access Journals (Sweden)

    Sidarta A. Lima

    2010-03-01

    Full Text Available A new three-scale model to describe the coupling between pH-dependent flows and transient ion transport, including adsorption phenomena in kaolinite clays, is proposed. The kaolinite is characterized by three separate nano/micro and macroscopic length scales. The pore (micro-scale is characterized by micro-pores saturated by an aqueous solution containing four monovalent ions and charged solid particles surrounded by thin electrical double layers. The movement of the ions is governed by the Nernst-Planck equations, and the influence of the double layers upon the flow is dictated by the Helmholtz-Smoluchowski slip boundary condition on the tangential velocity. In addition, an adsorption interface condition for the Na+ transportis postulated to capture its retention in the electrical double layer. Thetwo-scalenano/micro model including salt adsorption and slip boundary condition is homogenized to the Darcy scale and leads to the derivation of macroscopic governing equations. One of the notable features of the three-scale model is there construction of the constitutive law of effective partition coefficient that governs the sodium adsorption in the double layer. To illustrate the feasibility of the three-scale model in simulating soil decontamination by electrokinetics, the macroscopic model is discretized by the finite volume method and the desalination of a kaolinite sample by electrokinetics is simulated.Neste artigo propomos um modelo em três escalas para descrever o acoplamento entre o fluxo eletroosmótico e o transporte de íons incluindo fenômenos de adsorção em uma caulinita. A argila é caracterizada por três escalas nano/micro e macroscópica. A escala microscópica é constituída por micro-poros saturados por uma solução aquosa contendo quatro íons monovalentes e partículas sólidas carregadas eletricamente circundadas por uma dupla camada elétrica fina. O movimento dos íons é governado pelas equações de Nernst-Planck e a

  15. Separation of oil palm shell and kernel by using kaolinite media

    Directory of Open Access Journals (Sweden)

    Sukpong Sirinupong

    2003-05-01

    Full Text Available The objective of this research is to investigate the possibility of using kaolinite from Ranong province as media in the oil palm shell and kernel separation process by means of heavy media separation. The effect of specific gravity of the slurry, type and amount of dispersant and type of clays on suspension of media and efficiency of separation were studied. It was found that the specific gravity of oil palm shell and kernel are 1.40 and 1.20 respectively. While the average specific gravity of kaolinite grade MRD-B85, RANONG-325 and commercial clay from Univanich Group. PCL., are 2.54, 2.65 and 2.46 respectively. It was apparent that the viscosity of clay slurry increased with the specific gravity of the slurry. For MRD-B85 and RANONG- 325 clays which have the average particle sizes of 10 and 12 microns, the pH of their slurries of about 5.84 and 6.33 respectively were obtained and at these conditions stability of the slurry rarely occurred and they could not be used for separation. However, these clays can also be utilized as media when dispersant such asCalgon or sodium silicate is applied to their slurries. It was found that the efficiency of separation depends on specific gravity and viscosity of the slurry, type and particle size of kaolinite and dosage of dispersant. The optimum separating conditions for MRD-B85 clay were the dosage of Calgon of 0.15% (or 1.5 kg/t of clay at the specific gravity of the slurry of 1.20-1.24 (27-32% Solids in which a pH of 6.14 and viscosity of 104 cP to very low value (could not be measured were obtained. Thus, kernel yielded 97.57-100% and shell contamination of 1.48-6.32% was achieved. While sodium silicate was applied to the slurry about 0.15% at the specific gravity of 1.22, pH of 6.74 and viscosity of 238 cP were obtained and kernel could be recovered 100% with shell contamination of 8.36%. When 0.15% Calgon or 0.25% sodium silicate was introduced to the RANONG-325 clay slurry at the specific gravity

  16. Evaluation of kaolinite clays of Moa for the production of cement based clinker-calcined clay-limestone (LC3

    Directory of Open Access Journals (Sweden)

    Roger S. Almenares-Reyes

    2016-12-01

    Full Text Available Clay materials from two outcrops of the Moa region were analyzed to determine their potential use as supplementary cementitious material in the production of ternary cements based on limestone-calcined clay. The clays were characterized by atomic absorption spectroscopy (EAA, X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FTIR and thermogravimetric analysis (ATG. These methods revealed high aluminum in clays, moderate kaolinite content, a disordered structure and the presence of impurities. The solubility of aluminum and silicon in alkali and the compressive strength of LC3 systems is proportional to their content in clay, being higher for the one with higher kaolinite content and greater structural disorder (outcrop D1, although the clay of both outcrops may constitute supplementary cementitious materials in the production of ternary cements based clinker-calcined clay-limestone. The suitable thermal activation range for both clays is between 650 ° C and 850 ° C.

  17. Development of an Electronic Medical Record Based Alert for Risk of HIV Treatment Failure in a Low-Resource Setting

    Science.gov (United States)

    Puttkammer, Nancy; Zeliadt, Steven; Balan, Jean Gabriel; Baseman, Janet; Destiné, Rodney; Domerçant, Jean Wysler; France, Garilus; Hyppolite, Nathaelf; Pelletier, Valérie; Raphael, Nernst Atwood; Sherr, Kenneth; Yuhas, Krista; Barnhart, Scott

    2014-01-01

    Background The adoption of electronic medical record systems in resource-limited settings can help clinicians monitor patients' adherence to HIV antiretroviral therapy (ART) and identify patients at risk of future ART failure, allowing resources to be targeted to those most at risk. Methods Among adult patients enrolled on ART from 2005–2013 at two large, public-sector hospitals in Haiti, ART failure was assessed after 6–12 months on treatment, based on the World Health Organization's immunologic and clinical criteria. We identified models for predicting ART failure based on ART adherence measures and other patient characteristics. We assessed performance of candidate models using area under the receiver operating curve, and validated results using a randomly-split data sample. The selected prediction model was used to generate a risk score, and its ability to differentiate ART failure risk over a 42-month follow-up period was tested using stratified Kaplan Meier survival curves. Results Among 923 patients with CD4 results available during the period 6–12 months after ART initiation, 196 (21.2%) met ART failure criteria. The pharmacy-based proportion of days covered (PDC) measure performed best among five possible ART adherence measures at predicting ART failure. Average PDC during the first 6 months on ART was 79.0% among cases of ART failure and 88.6% among cases of non-failure (pART initiation were added to PDC, the risk score differentiated between those who did and did not meet failure criteria over 42 months following ART initiation. Conclusions Pharmacy data are most useful for new ART adherence alerts within iSanté. Such alerts offer potential to help clinicians identify patients at high risk of ART failure so that they can be targeted with adherence support interventions, before ART failure occurs. PMID:25390044

  18. Development of an electronic medical record based alert for risk of HIV treatment failure in a low-resource setting.

    Directory of Open Access Journals (Sweden)

    Nancy Puttkammer

    Full Text Available The adoption of electronic medical record systems in resource-limited settings can help clinicians monitor patients' adherence to HIV antiretroviral therapy (ART and identify patients at risk of future ART failure, allowing resources to be targeted to those most at risk.Among adult patients enrolled on ART from 2005-2013 at two large, public-sector hospitals in Haiti, ART failure was assessed after 6-12 months on treatment, based on the World Health Organization's immunologic and clinical criteria. We identified models for predicting ART failure based on ART adherence measures and other patient characteristics. We assessed performance of candidate models using area under the receiver operating curve, and validated results using a randomly-split data sample. The selected prediction model was used to generate a risk score, and its ability to differentiate ART failure risk over a 42-month follow-up period was tested using stratified Kaplan Meier survival curves.Among 923 patients with CD4 results available during the period 6-12 months after ART initiation, 196 (21.2% met ART failure criteria. The pharmacy-based proportion of days covered (PDC measure performed best among five possible ART adherence measures at predicting ART failure. Average PDC during the first 6 months on ART was 79.0% among cases of ART failure and 88.6% among cases of non-failure (p<0.01. When additional information including sex, baseline CD4, and duration of enrollment in HIV care prior to ART initiation were added to PDC, the risk score differentiated between those who did and did not meet failure criteria over 42 months following ART initiation.Pharmacy data are most useful for new ART adherence alerts within iSanté. Such alerts offer potential to help clinicians identify patients at high risk of ART failure so that they can be targeted with adherence support interventions, before ART failure occurs.

  19. Innovative direct energy conversion systems using electronic adiabatic processes of electron fluid in solid conductors: new plants of electrical power and hydrogen gas resources without environmental pollutions

    International Nuclear Information System (INIS)

    Kondoh, Y.; Kondo, M.; Shimoda, K.; Takahashi, T.

    2001-07-01

    It is shown that using a novel recycling process of the environmental thermal energy, innovative permanent auto-working direct energy converter systems (PA-DEC systems) from the environmental thermal to electrical and/or chemical potential (TE/CP) energies, abbreviated as PA-TE/CP-DEC systems, can be used for new auto-working electrical power plants and the plants of the compressible and conveyable hydrogen gas resources at various regions in the whole world, with contributions to the world peace and the economical development in the south part of the world. It is shown that the same physical mechanism by free electrons and electrical potential determined by temperature in conductors, which include semiconductors, leads to the Peltier effect and the Seebeck one. It is experimentally clarified that the long distance separation between two π type elements of the heat absorption (HAS) and the production one (HPS) of the Peltier effect circuit system or between the higher temperature side (HTS) and the lower one (LTS) of the Seebeck effect circuit one does not change in the whole for the both effects. By using present systems, we do not need to use petrified fuels such as coals, oils, and natural gases in order to decrease the greenhouse effect by the CO 2 surrounding the earth. Furthermore, we do not need plats of nuclear fissions that left radiating wastes, i.e., with no environmental pollutions. The PA-TE/CP-DEC systems can be applicable for several km scale systems to the micro ones, such as the plants of the electrical power, the compact transportable hydrogen gas resources, a large heat energy container, which can be settled at far place from thermal energy absorbing area, the refrigerators, the air conditioners, home electrical apparatuses, and further the computer elements. It is shown that the simplest PA-TE/CP-DEC system can be established by using only the Seebeck effect components and the resolving water ones. It is clarified that the externally applied

  20. Preparation and characterization of polyacrylamide-modified kaolinite containing poly [acrylic acid-co-methylene bisacrylamide] nanocomposite hydrogels

    DEFF Research Database (Denmark)

    Zaharia, Anamaria; Sarbu, Andrei; Radu, Anita-Laura

    2015-01-01

    Novel nanocomposite hydrogel structures based on cross-linked poly(acrylic acid) (PAA) and kaolinite (Kaol), modified with different loadings of polyacrylamide (PAAm), were prepared by inverse dispersion polymerization. Ceric ammonium nitrate as an initiator in the presence of nitric acid was used...... of Kaol particles in the polyacrylic acid matrix, thereby leading to enhanced interactions and furthermore to improved mechanical properties of the final hydrogels....

  1. Sorption of cobalt in zeolites and natural clays of the clinoptilolite and kaolinite type

    International Nuclear Information System (INIS)

    Davila R, J.I.; Solache R, M.

    2006-01-01

    In this work the sorption of cobalt of aqueous solutions in two natural zeolites (clinoptilolite) and a clay (kaolinite) of origin in the center-north region of Mexico is evaluated. The effect of the pH and the time of contact in the process of sorption were evaluated. The cobalt retained in the aluminosilicates was determined by neutron activation analysis. The cobalt sorption in the materials in a range of pH from 4 to 7 does not present significant variations. The studies of reaction kinetics show a very fast sorption in the first 5 hours of contact, reaching the equilibrium in approximately 24 hours. The kinetics of sorption of the cobalt ions was represented better by the Ritchie reaction model modified of second order. The experimental data for the zeolites obtained at ambient temperature and varying the concentration were adjusted to the models of Freundlich, Langmuir and Freundlich-Langmuir isotherms and it was observed that the cobalt sorption it behaves according to the Freundlich isotherm model. (Author)

  2. Experimental study and mathematical model on remediation of Cd spiked kaolinite by electrokinetics

    International Nuclear Information System (INIS)

    Mascia, Michele; Palmas, Simonetta; Polcaro, Anna Maria; Vacca, Annalisa; Muntoni, Aldo

    2007-01-01

    An experimental study on electrokinetic removal of cadmium from kaolinitic clays is presented in this work, which is aimed to investigate the effect of surface reactions on the electrokinetic process. Enhanced electrokinetic tests were performed in which the pH of the compartments was controlled. Cadmium spiked kaolin was adopted in the experimental runs. On the basis of the experimental results, a numerical model was formulated to simulate the cadmium (Cd) transport under an electric field by combining a one-dimensional diffusion-advection model with a geochemical model: the combined model describes the contaminant transport driven by chemical and electrical gradients, as well as the effect of the surface reactions. The geochemical model utilized parameters derived from the literature, and it was validated by experimental data obtained by sorption and titration experiments. Electrokinetic tests were utilized to validate the results of the proposed model. A good prediction of the behaviour of the soil/cadmium ions system under electrical field was obtained: the differences between experimental and model predicted profiles for the species considered were less than 5% in all the examined conditions

  3. Sorption of lambda-cyhalothrin, cypermethrin, deltamethrin and fenvalerate to quartz, corundum, kaolinite and montmorillonite.

    Science.gov (United States)

    Oudou, H Chaaieri; Hansen, H C Bruun

    2002-12-01

    Sorption to mineral surfaces may be important for retention and degradation of hydrophobic pesticides in subsoils and aquifers poor in organic matter. In this work the title pyrethroids have been used to investigate selective interactions with the surfaces of four minerals. Sorption of the four pyrethroids was quantified in batch experiments with initial pyrethroid concentrations of 1-100 microg/l. Sorption to centrifuge tubes used in the batch experiments accounted for 25-60% of total sorption. Net sorption was obtained from total sorption after subtracting the amounts of pyrethroids sorbed to centrifuge tubes used. All isotherms could be fitted by the Freundlich equation with n ranging between 0.9 and 1.1. Bonding affinities per unit surface area decreased in the order: corundum > quartz > montmorillonite approximately equal kaolinite. A similar sequence as found for the total surface tension of the minerals. All minerals showed the same selectivity order with respect to sorption affinity of the four pyrethroids: lambda-cyhalothrin > deltamethrin > cypermethrin > fenvalerate, which shows that the most hydrophobic compound is sorbed most strongly. Stereochemical properties of the four pyrethroid formulations may also contribute to the selectivity pattern.

  4. Adsorption of Sr on kaolinite, illite and montmorillonite at high ionic strengths

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, J.J.; Langmuir, D. (Colorado School of Mines, Golden (USA). Dept. of Chemistry and Geochemistry)

    1991-01-01

    Experimental measurements of Sr adsorption onto kaolinite, illite and montmorillonite in up to 4.0 mol/kg NaCl solutions, were modelled with the surface ionization and complexation triple-layer (SIC) model (Davis et al.) to determine if model adjustments were required for high ionic strengths. Improved model fits to the adsorption data were obtained at high ionic strengths, reflecting a lowered sensitivity of the model. A general reduction in Sr adsorption with increasing ionic strength was caused by an increase in the outer layer surface charge, rather than by a drop in the number of available adsorption sites. Sensitivity analysis showed that the range of values of model constants yielding acceptable fits was as large as variations reported in the literature for these constants. The study demonstrates that adsorption will not retard Sr migration in brines, and that it is unnecessary to introduce a Pitzer ion interaction subroutine in the SIC model when considering adsorption at high ionic strengths. (orig.).

  5. On the Kaolinite Floc Size at the Steady State of Flocculation in a Turbulent Flow.

    Science.gov (United States)

    Zhu, Zhongfan; Wang, Hongrui; Yu, Jingshan; Dou, Jie

    2016-01-01

    The flocculation of cohesive fine-grained sediment plays an important role in the transport characteristics of pollutants and nutrients absorbed on the surface of sediment in estuarine and coastal waters through the complex processes of sediment transport, deposition, resuspension and consolidation. Many laboratory experiments have been carried out to investigate the influence of different flow shear conditions on the floc size at the steady state of flocculation in the shear flow. Most of these experiments reported that the floc size decreases with increasing shear stresses and used a power law to express this dependence. In this study, we performed a Couette-flow experiment to measure the size of the kaolinite floc through sampling observation and an image analysis system at the steady state of flocculation under six flow shear conditions. The results show that the negative correlation of the floc size on the flow shear occurs only at high shear conditions, whereas at low shear conditions, the floc size increases with increasing turbulent shear stresses regardless of electrolyte conditions. Increasing electrolyte conditions and the initial particle concentration could lead to a larger steady-state floc size.

  6. Interactions Between Suspended Kaolinite Deposition and Hyporheic Exchange Flux Under Losing and Gaining Flow Conditions

    Science.gov (United States)

    Fox, Aryeh; Packman, Aaron I.; Boano, Fulvio; Phillips, Colin B.; Arnon, Shai

    2018-05-01

    Fine particle deposition and streambed clogging affect many ecological and biogeochemical processes, but little is known about the effects of groundwater flow into and out of rivers on clogging. We evaluated the effects of losing and gaining flow on the deposition of suspended kaolinite clay particles in a sand streambed and the resulting changes in rates and patterns of hyporheic exchange flux (HEF). Observations of clay deposition from the water column, clay accumulation in the streambed sediments, and water exchange with the bed demonstrated that clay deposition in the bed substantially reduced both HEF and the size of the hyporheic zone. Clay deposition and HEF were strongly coupled, leading to rapid clogging in areas of water and clay influx into the bed. Local clogging diverted exchanged water laterally, producing clay deposit layers that reduced vertical hyporheic flow and favored horizontal flow. Under gaining conditions, HEF was spatially constrained by upwelling water, which focused clay deposition in a small region on the upstream side of each bed form. Because the area of inflow into the bed was smallest under gaining conditions, local clogging required less clay mass under gaining conditions than neutral or losing conditions. These results indicate that losing and gaining flow conditions need to be considered in assessments of hyporheic exchange, fine particle dynamics in streams, and streambed clogging and restoration.

  7. Adsorption behavior of strontium on kaolinite and montmorillonite and their mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Atun, G. [Istanbul Univ. (Turkey). Engineering Faculty, Chemistry Dept.; Bascetin, E. [Cekmece Nuclear Research and Training Center, Istanbul (Turkey)

    2004-07-01

    {sup 90}Sr, with a long half-life of 28.5 years, is the most dangerous strontium isotope. The adsorption behavior of radionuclides in the environment are closely related to the safe disposal of radioactive wastes. Since various types of minerals may exist in and around the repositories used for ultimate disposal of nuclear waste, the adsorption behavior of certain radionuclides onto and from these minerals and similar adsorbents should be studied in order to estimate the rates of transport of the nuclides in the event of water penetration into and through the repository. Information on the adsorption properties of the purified individual clay minerals may not be sufficient to predict the adsorption properties of a corresponding mixture, because these clay minerals may interact with each other and lead to modification of the adsorption properties of the mixture as compared to the pure minerals. The adsorption behavior of strontium on kaolinite and montmorillonite minerals and their mixtures was studied by means of a batch method and a tracer technique. (orig.)

  8. Adsorption of barium on kaolinite, illite and montmorillonite at various ionic strengths

    Energy Technology Data Exchange (ETDEWEB)

    Atun, G.; Bascetin, E. [Istanbul Univ., Dept. of Chemistry, Istanbul (Turkey)

    2003-07-01

    The sorption behaviour of Ba{sup 2+} in three different clay minerals from various regions of Turkey has been investigated by means of a tracer technique using {sup 133}Ba in batch experiments. Sorption of Ba{sup 2+} on montmorillonite, kaolinite and illite has been studied in mixed solutions of BaCl{sub 2} and NaCl at ionic strengths ranging from 1 x 10{sup -3}M to 1 x 10{sup -1}M. The L-shape exchange isotherms for Ba{sup 2+}-Na{sup +} systems are well defined by a Langmuir type equation. The exchange capacity of Ba{sup 2+} ions for all three clay minerals increased with decreasing ionic strength. The adsorption data were fitted to a Freundlich isotherm and empirical Freundlich parameters enabled to the generation of a site distribution function. The selectivity coefficients were nearly constant at low Ba loading and decreased as loading increased. This behavior was an indication of an ion exchange process between Ba{sup 2+} and Na{sup +} ions.

  9. Behaviour of the surface hydroxide groups of exfoliated kaolinite in the gas phase and during water adsorption.

    Science.gov (United States)

    Táborosi, Attila; Szilágyi, Róbert K

    2016-02-14

    The chemical and physical properties, and thus the reactivity of phylloaluminosilicates can be tailored by intercalation, delamination, and exfoliation processes. In going from the periodic crystalline to the molecular exfoliated phase, surface defects and modifications gain importance as each face of the phylloaluminosilicate comes in direct contact with the external chemical environment. In this work, we extend our earlier studies on the molecular cluster modelling of exfoliated kaolinite sheets by evaluating the positions and orientations of surface hydroxide groups and bridging oxide anions, as the sites of reactivity. The previous focus on the inner chemical environment of a single kaolinite layer is shifted to the surface exposed octahedral aluminium-hydroxide and tetrahedral silicon-oxide sheets. The combination of semi-empirical, ab initio wave function, and density functional calculations unanimously support the amphoteric nature of the surface hydroxide groups with respect to H-bonding donor/acceptor capabilities. To a lesser extent, we observe the same for the bridging oxide anions. This is in contrast to the crystalline phase, which manifests only donor orientation for maintaining an inter-layer H-bond network. These results suggest that both electrophilic and nucleophilic characteristics of the octahedral and tetrahedral sheets need to be considered during intercalation and concomitant exfoliation of the kaolinite sheets.

  10. Equilibrium, kinetic and thermodynamic studies of adsorption of Pb(II) from aqueous solution onto Turkish kaolinite clay

    International Nuclear Information System (INIS)

    Sari, Ahmet; Tuzen, Mustafa; Citak, Demirhan; Soylak, Mustafa

    2007-01-01

    The adsorption of Pb(II) onto Turkish (Bandirma region) kaolinite clay was examined in aqueous solution with respect to the pH, adsorbent dosage, contact time, and temperature. The linear Langmuir and Freundlich models were applied to describe equilibrium isotherms and both models fitted well. The monolayer adsorption capacity was found as 31.75 mg/g at pH 5 and 20 deg. C. Dubinin-Radushkevich (D-R) isotherm model was also applied to the equilibrium data. The mean free energy of adsorption (13.78 kJ/mol) indicated that the adsorption of Pb(II) onto kaolinite clay may be carried out via chemical ion-exchange mechanism. Thermodynamic parameters, free energy (ΔG o ), enthalpy (ΔH o ) and entropy (ΔS o ) of adsorption were also calculated. These parameters showed that the adsorption of Pb(II) onto kaolinite clay was feasible, spontaneous and exothermic process in nature. Furthermore, the Lagergren-first-order, pseudo-second-order and the intraparticle diffusion models were used to describe the kinetic data. The experimental data fitted well the pseudo-second-order kinetics

  11. Preparation of Composite Hydrogel Based on Polyacrylamide and the Effect of Kaolinite on Its Properties in the Reservoir Conditions

    Directory of Open Access Journals (Sweden)

    Farhad Salimi

    2013-01-01

    Full Text Available A gel composite (based on polyacrylamide and crosslinker Cr(III acetate was prepared by solvent method (distillate and water formation and nanoclay particle (kaolinite. Using XRD tests, d001 was evaluated for kaolinite nanoparticles in gel composite. Kaolinite modification using dimethyl-sulfoxide led to increase interlamellar spacing from 7.21 to 10.82 o A. Based on the results obtained for samples prepared from unmodified clay besides the pure clay, there is a wide peak at 2θ = 8o; which is a representative of polymer diffusion between the clay layers. For the sample prepared from modified clay, no increase in interlamellar space was observed. Addition of 15% clay (modified and unmodified caused the syneresis to reduce by 20%. The gelation time for composites prepared from both types of clays increased due to increases in clay concentration, which this increase for the sample prepared from unmodified clay was greater. The viscosity of gel for samples prepared from modified clay increased due to increased clay concentration, which reached its maximum for 15% clay concentration. However for unmodified clay the maximum value of viscosity was observed for 30% clay concentration.

  12. Consumer reports [electronic resource

    National Research Council Canada - National Science Library

    1942-01-01

    ... only. A limited number of selected reports, advice on product selection and safety alerts are freely available, as are a five year listing of product recalls, a listing of major consumer product...

  13. The electronic Rothamsted Archive (e-RA), an online resource for data from the Rothamsted long-term experiments.

    Science.gov (United States)

    Perryman, Sarah A M; Castells-Brooke, Nathalie I D; Glendining, Margaret J; Goulding, Keith W T; Hawkesford, Malcolm J; Macdonald, Andy J; Ostler, Richard J; Poulton, Paul R; Rawlings, Christopher J; Scott, Tony; Verrier, Paul J

    2018-05-15

    The electronic Rothamsted Archive, e-RA (www.era.rothamsted.ac.uk) provides a permanent managed database to both securely store and disseminate data from Rothamsted Research's long-term field experiments (since 1843) and meteorological stations (since 1853). Both historical and contemporary data are made available via this online database which provides the scientific community with access to a unique continuous record of agricultural experiments and weather measured since the mid-19 th century. Qualitative information, such as treatment and management practices, plans and soil information, accompanies the data and are made available on the e-RA website. e-RA was released externally to the wider scientific community in 2013 and this paper describes its development, content, curation and the access process for data users. Case studies illustrate the diverse applications of the data, including its original intended purposes and recent unforeseen applications. Usage monitoring demonstrates the data are of increasing interest. Future developments, including adopting FAIR data principles, are proposed as the resource is increasingly recognised as a unique archive of data relevant to sustainable agriculture, agroecology and the environment.

  14. Principles of formation of the content of an educational electronic resource on the basis of general and didactic patterns of learning

    Directory of Open Access Journals (Sweden)

    Ольга Юрьевна Заславская

    2018-12-01

    Full Text Available The article considers the influence of the development of technical means of teaching on the effectiveness of educational and methodical resources. Modern opportunities of information and communication technologies allow creating electronic educational resources that represent educational information that automates the learning process, provide information assistance, if necessary, collect and process statistical information on the degree of development of the content of the school material by schoolchildren, set an individual trajectory of learning, and so on. The main principle of data organization is the division of the training course into separate sections on the thematic elements and components of the learning process. General regularities include laws that encompass the entire didactic system, and in specific (particular cases, those whose actions extend to a separate component (aspect of the system. From the standpoint of the existence of three types of electronic training modules in the aggregate content of the electronic learning resource - information, control and module of practical classes - the principles of the formation of the electronic learning resource, in our opinion, should regulate all these components. Each of the certain principles is considered in the groups: scientific orientation, methodological orientation, systemic nature, accounting of interdisciplinary connections, fundamentalization, systematic and dosage sequence, rational use of study time, accessibility, minimization, operationalization of goals, unified identification diagnosis.

  15. The module of methodical support in system of electronic educational resources as the innovative element of the modern maintenance of formation

    Directory of Open Access Journals (Sweden)

    Ольга Николаевна Крылова

    2009-06-01

    Full Text Available The article introduces some results of research, which were devoted to evaluation of tearches' mobility to introduce innovations in the contents of education. The author considers innovative potential of modules of the methodical support for system of electronic educational resources.

  16. Charting a Course through CORAL: Texas A&M University Libraries' Experience Implementing an Open-Source Electronic Resources Management System

    Science.gov (United States)

    Hartnett, Eric; Beh, Eugenia; Resnick, Taryn; Ugaz, Ana; Tabacaru, Simona

    2013-01-01

    In 2010, after two previous unsuccessful attempts at electronic resources management system (ERMS) implementation, Texas A&M University (TAMU) Libraries set out once again to find an ERMS that would fit its needs. After surveying the field, TAMU Libraries selected the University of Notre Dame Hesburgh Libraries-developed, open-source ERMS,…

  17. Cathodoluminescence (CL) and electron paramagnetic resonance (EPR) studies of clay minerals

    International Nuclear Information System (INIS)

    Goetze, J.; Ploetze, M.; Goette, T.; Neuser, R.D.; Richter, D.K.

    2002-01-01

    Sheet silicates of the serpentine-kaolin-group (serpentine, kaolinite, dickite, nacrite, halloysite), the talc-pyrophyllite-group (talc, pyrophyllite), the smectite-group (montmorillonite), and illite (as a mineral of the mica-group) were investigated to obtain information concerning their cathodoluminescence behavior. The study included analyses by cathodoluminescence (CL microscopy and spectroscopy), electron paramagnetic resonance (EPR), x-ray diffraction (XRD), scanning electron microscopy (SEM) and trace element analysis. In general, all dioctahedral clay minerals exhibit a visible CL. Kaolinite, dickite, nacrite and pyrophyllite have a characteristic deep blue CL, whereas halloysite emission is in the greenish-blue region. On the contrary, the trioctahedral minerals (serpentine, talc) and illite do not show visible CL. The characteristic blue CL is caused by an intense emission band around 400 nm (double peak with two maxima at 375 and 410 nm). EPR measurements indicate that his blue emission can be related to radiation induced defect centers (RID), which occur as electron holes trapped on apical oxygen (Si-O center) or located at the Al-O-Al group (Al substituting Si in the tetrahedron). Additional CL emission bands were detected at 580 nm in halloysite and kaolinite, and between 700 and 800 nm in kaolinite, dickite, nacrite and pyrophyllite. Time-resolved spectral CL measurements show typical luminescence kinetics for the different clay minerals, which enable differentiation between the various dioctahedral minerals (e.g. kaolinite and dickite), even in thin section. (author)

  18. Electronics

    Science.gov (United States)

    2001-01-01

    International Acer Incorporated, Hsin Chu, Taiwan Aerospace Industrial Development Corporation, Taichung, Taiwan American Institute of Taiwan, Taipei, Taiwan...Singapore and Malaysia .5 - 4 - The largest market for semiconductor products is the high technology consumer electronics industry that consumes up...Singapore, and Malaysia . A new semiconductor facility costs around $3 billion to build and takes about two years to become operational

  19. Probing the Surface Charge on the Basal Planes of Kaolinite Particles with High-Resolution Atomic Force Microscopy.

    Science.gov (United States)

    Kumar, N; Andersson, M P; van den Ende, D; Mugele, F; Siretanu, I

    2017-12-19

    High-resolution atomic force microscopy is used to map the surface charge on the basal planes of kaolinite nanoparticles in an ambient solution of variable pH and NaCl or CaCl 2 concentration. Using DLVO theory with charge regulation, we determine from the measured force-distance curves the surface charge distribution on both the silica-like and the gibbsite-like basal plane of the kaolinite particles. We observe that both basal planes do carry charge that varies with pH and salt concentration. The silica facet was found to be negatively charged at pH 4 and above, whereas the gibbsite facet is positively charged at pH below 7 and negatively charged at pH above 7. Investigations in CaCl 2 at pH 6 show that the surface charge on the gibbsite facet increases for concentration up to 10 mM CaCl 2 and starts to decrease upon further increasing the salt concentration to 50 mM. The increase of surface charge at low concentration is explained by Ca 2+ ion adsorption, while Cl - adsorption at higher CaCl 2 concentrations partially neutralizes the surface charge. Atomic resolution imaging and density functional theory calculations corroborate these observations. They show that hydrated Ca 2+ ions can spontaneously adsorb on the gibbsite facet of the kaolinite particle and form ordered surface structures, while at higher concentrations Cl - ions will co-adsorb, thereby changing the observed ordered surface structure.

  20. Thermally induced permeability reduction due to particle migration in sandstones: the effect of temperature on kaolinite mobilisation and aggregation

    DEFF Research Database (Denmark)

    Rosenbrand, Esther; Fabricius, Ida Lykke; Yuan, Hao

    2012-01-01

    The seasonal imbalance in supply and demand of renewable energy requires seasonal storage, which potentially may be achieved by hot water injection in geothermal aquifers to minimize heat loss by advection. A reduction of porosity and permeability is a risk of heating the rock above the in...... the interaction energy between quartz and kaolinite particles for different saturating fluids. The results are compared to the published data addressing the effect of temperature on permeability. This provides a qualitative explanation for the observed changes in permeability with temperature for the tests...

  1. Flash calcination of kaolinite rich clay and impact of process conditions on the quality of the calcines

    DEFF Research Database (Denmark)

    Gebremariam, Abraham Teklay; Yin, Chungen; Rosendahl, Lasse

    2016-01-01

    Use of properly calcined kaolinite rich clay (i.e., metakaolin) to offset part of CO2-intensive clinkers not only reduces CO2 footprint from cement industry but also improves the performance of concrete. However, calcination under inappropriately high temperatures or long retention times may...... suspension calciner. The model is validated by the experimental data (e.g., the degree of dehydroxylation and the density of the calcines). Based on the model, the impacts of process conditions and feed properties on the quality of the calcination products are thoroughly examined....

  2. Evaluation of three electronic report processing systems for preparing hydrologic reports of the U.S Geological Survey, Water Resources Division

    Science.gov (United States)

    Stiltner, G.J.

    1990-01-01

    In 1987, the Water Resources Division of the U.S. Geological Survey undertook three pilot projects to evaluate electronic report processing systems as a means to improve the quality and timeliness of reports pertaining to water resources investigations. The three projects selected for study included the use of the following configuration of software and hardware: Ventura Publisher software on an IBM model AT personal computer, PageMaker software on a Macintosh computer, and FrameMaker software on a Sun Microsystems workstation. The following assessment criteria were to be addressed in the pilot studies: The combined use of text, tables, and graphics; analysis of time; ease of learning; compatibility with the existing minicomputer system; and technical limitations. It was considered essential that the camera-ready copy produced be in a format suitable for publication. Visual improvement alone was not a consideration. This report consolidates and summarizes the findings of the electronic report processing pilot projects. Text and table files originating on the existing minicomputer system were successfully transformed to the electronic report processing systems in American Standard Code for Information Interchange (ASCII) format. Graphics prepared using a proprietary graphics software package were transferred to all the electronic report processing software through the use of Computer Graphic Metafiles. Graphics from other sources were entered into the systems by scanning paper images. Comparative analysis of time needed to process text and tables by the electronic report processing systems and by conventional methods indicated that, although more time is invested in creating the original page composition for an electronically processed report , substantial time is saved in producing subsequent reports because the format can be stored and re-used by electronic means as a template. Because of the more compact page layouts, costs of printing the reports were 15% to 25

  3. Electronic resources of the rare books and valuable editions department of the Central Scientific Library of the V.N. Karazin Kharkiv National University: open access for research

    Directory of Open Access Journals (Sweden)

    І. К. Журавльова

    2014-12-01

    Full Text Available The article describes tasks that electronic collections of rare books fulfill: broad access for readers to rare and valuable editions providing, preservation of ensuring of the original. On the example of the electronic collection of the Central Scientific Library of the V.N. Karazin Kharkiv National University – «eScriptorium: electronic archive of rare books and manuscripts for research and education» the possibility of the full-text resources of the valuable editions using is shown. The principles of creation, structure, chronological frameworks, directions of adding the documents to the archive are represented. The perspectives of the project development are outlined as well as examples of the digital libraries of the European countries and Ukraine are provided, the actual task of preserving the originals of the rare books of the country is raised, the innovative approaches to serving users with electronic resources are considered. The evidences of cooperation of the Central Scientific Library of the V.N. Karazin Kharkiv National University with the largest world digital libraries: World Digital Library and Europeana are provided.

  4. The use of quality benchmarking in assessing web resources for the dermatology virtual branch library of the National electronic Library for Health (NeLH).

    Science.gov (United States)

    Kamel Boulos, M N; Roudsari, A V; Gordon, C; Muir Gray, J A

    2001-01-01

    In 1998, the U.K. National Health Service Information for Health Strategy proposed the implementation of a National electronic Library for Health to provide clinicians, healthcare managers and planners, patients and the public with easy, round the clock access to high quality, up-to-date electronic information on health and healthcare. The Virtual Branch Libraries are among the most important components of the National electronic Library for Health. They aim at creating online knowledge based communities, each concerned with some specific clinical and other health-related topics. This study is about the envisaged Dermatology Virtual Branch Libraries of the National electronic Library for Health. It aims at selecting suitable dermatology Web resources for inclusion in the forthcoming Virtual Branch Libraries after establishing preliminary quality benchmarking rules for this task. Psoriasis, being a common dermatological condition, has been chosen as a starting point. Because quality is a principal concern of the National electronic Library for Health, the study includes a review of the major quality benchmarking systems available today for assessing health-related Web sites. The methodology of developing a quality benchmarking system has been also reviewed. Aided by metasearch Web tools, candidate resources were hand-selected in light of the reviewed benchmarking systems and specific criteria set by the authors. Over 90 professional and patient-oriented Web resources on psoriasis and dermatology in general are suggested for inclusion in the forthcoming Dermatology Virtual Branch Libraries. The idea of an all-in knowledge-hallmarking instrument for the National electronic Library for Health is also proposed based on the reviewed quality benchmarking systems. Skilled, methodical, organized human reviewing, selection and filtering based on well-defined quality appraisal criteria seems likely to be the key ingredient in the envisaged National electronic Library for

  5. Barriers to electronic access and delivery of educational information in resource constrained public schools: a case of Greater Tubatse Municipality

    CSIR Research Space (South Africa)

    Pholotho, T

    2016-05-01

    Full Text Available Information and Communication Technologies (ICTs) are capable of expanding access to quality education, educational resources and provide teachers with new skills. Nevertheless, a majority of rural public schools have limited ICTs, mainly due...

  6. Adsorption and structure of water on kaolinite surfaces: possible insight into ice nucleation from grand canonical monte carlo calculations.

    Science.gov (United States)

    Croteau, T; Bertram, A K; Patey, G N

    2008-10-30

    Grand canonical Monte Carlo calculations are used to determine water adsorption and structure on defect-free kaolinite surfaces as a function of relative humidity at 235 K. This information is then used to gain insight into ice nucleation on kaolinite surfaces. Results for both the SPC/E and TIP5P-E water models are compared and demonstrate that the Al-surface [(001) plane] and both protonated and unprotonated edges [(100) plane] strongly adsorb at atmospherically relevant relative humidities. Adsorption on the Al-surface exhibits properties of a first-order process with evidence of collective behavior, whereas adsorption on the edges is essentially continuous and appears dominated by strong water lattice interactions. For the protonated and unprotonated edges no structure that matches hexagonal ice is observed. For the Al-surface some of the water molecules formed hexagonal rings. However, the a o lattice parameter for these rings is significantly different from the corresponding constant for hexagonal ice ( Ih). A misfit strain of 14.0% is calculated between the hexagonal pattern of water adsorbed on the Al-surface and the basal plane of ice Ih. Hence, the ring structures that form on the Al-surface are not expected to be good building-blocks for ice nucleation due to the large misfit strain.

  7. A comparative study on the rheology and wave dissipation of kaolinite and natural Hendijan Coast mud, the Persian Gulf

    Science.gov (United States)

    Soltanpour, Mohsen; Samsami, Farzin

    2011-03-01

    The objective of this paper is to investigate the rheological behavior of kaolinite and Hendijan mud, located at the northwest part of the Persian Gulf, and the dissipative role of this muddy bed on surface water waves. A series of laboratory rheological tests was conducted to investigate the rheological response of mud to rotary and cyclic shear rates. While a viscoplastic Bingham model can successfully be applied for continuous controlled shear-stress tests, the rheology of fluid mud displays complex viscoelastic behavior in time-periodic motion. The comparisons of the behavior of natural Hendijan mud with commercial kaolinite show rheological similarities. A large number of laboratory wave-flume experiments were carried out with a focus on the dissipative role of the fluid mud. Assuming four rheological models of viscous, Kelvin-Voigt viscoelastic, Bingham viscoplastic, and viscoelastic-plastic for fluid mud layer, a numerical multi-layered model was applied to analyze the effects of different parameters of surface wave and muddy bed on wave attenuation. The predicted results based on different rheological models generally agree with the obtained wave-flume data implying that the adopted rheological model does not play an important role in the accuracy of prediction.

  8. Electronic Grey Literature in Accelerator Science and Its Allied Subjects : Selected Web Resources for Scientists and Engineers

    CERN Document Server

    Rajendiran, P

    2006-01-01

    Grey literature Web resources in the field of accelerator science and its allied subjects are collected for the scientists and engineers of RRCAT (Raja Ramanna Centre for Advanced Technology). For definition purposes the different types of grey literature are described. The Web resources collected and compiled in this article (with an overview and link for each) specifically focus on technical reports, preprints or e-prints, which meet the main information needs of RRCAT users.

  9. Intracrystalline fractionation of oxygen isotopes between hydroxyl and non-hydroxyl sites in kaolinite measured by thermal dehydroxylation and partial fluorination

    Science.gov (United States)

    Girard, Jean-Pierre; Savin, Samuel M.

    1996-02-01

    Thermal dehydroxylation and partial fluorination techniques were used to measure intracrystalline fractionation of oxygen isotopes between hydroxyl and non-hydroxyl sites in kaolinite. Several aliquots of a well characterized, fine-grained (rates, and target temperatures. Measured δ18O values of both the liberated water and the dehydroxylated residue are consistent over a wide range of temperatures (550 850°C) when dehydroxylation is performed in a single-step fashion at a rapid heating rate (>50°C/min.). Similar dehydroxylation experiments indicate that brucite dehydroxylation occurs without any significant isotopic fractionation of the oxygen isotopes. By extrapolation we postulate that no significant fractionation occurs during single-step thermal dehydroxylation of fine-grained kaolinite, provided that dehydroxylation is performed under well controlled conditions. In contrast, gibbsite dehydroxylation is accompanied by substantial isotopic fractionation. This is probably the result of the complex, multi-pathway dehydroxylation reaction of this mineral. Similarly, thermal dehydroxylation of coarsegrained (>1 μm) kaolinites and dickites of weathering and hydrothermal origin yield results that are dependent on the temperature of dehydroxylation. We suggest that this effect may be caused by isotopic exchange during diffusion of water molecules through coarse particles. Partial fluorination of fine-grained kaolinite in the presence of excess F2 at low temperatures (rate of reaction of hydroxyl oxygen than of non-hydroxyl oxygen, but examination of the isotopic data as well as XRD and IR analyses of the residues after partial fluorination indicates that the separation between the two types of oxygen is not complete. The results, therefore, do not yield a reliable δ18O value of the hydroxyl oxygen. The results of this study suggest that the thermal dehydroxylation technique may be appropriate for analysis of OH groups in fine-grained kaolinite. The partial

  10. Clinician‐selected Electronic Information Resources do not Guarantee Accuracy in Answering Primary Care Physicians’ Information Needs. A review of: McKibbon, K. Ann, and Douglas B. Fridsma. “Effectiveness of Clinician‐selected Electronic Information Resources for Answering Primary Care Physicians’ Information Needs.” Journal of the American Medical Informatics Association 13.6 (2006: 653‐9.

    Directory of Open Access Journals (Sweden)

    Martha Ingrid Preddie

    2008-03-01

    Full Text Available Objective – To determine if electronic information resources selected by primary care physicians improve their ability to answer simulated clinical questions.Design – An observational study utilizing hour‐long interviews and think‐aloud protocols.Setting – The offices and clinics of primary care physicians in Canada and the United States.Subjects – Twenty‐five primary care physicians of whom 4 were women, 17 were from Canada, 22 were family physicians,and 24 were board certified.Methods – Participants provided responses to 23 multiple‐choice questions. Each physician then chose two questions and looked for the answers utilizing information resources of their own choice. The search processes, chosen resources and search times were noted. These were analyzed along with data on the accuracy of the answers and certainties related to the answer to each clinical question prior to the search.Main results – Twenty‐three physicians sought answers to 46 simulated clinical questions. Utilizing only electronic information resources, physicians spent a mean of 13.0 (SD 5.5 minutes searching for answers to the questions, an average of 7.3(SD 4.0 minutes for the first question and 5.8 (SD 2.2 minutes to answer the second question. On average, 1.8 resources were utilized per question. Resources that summarized information, such as the Cochrane Database of Systematic Reviews, UpToDate and Clinical Evidence, were favored 39.2% of the time, MEDLINE (Ovid and PubMed 35.7%, and Internet resources including Google 22.6%. Almost 50% of the search and retrieval strategies were keyword‐based, while MeSH, subheadings and limiting were used less frequently. On average, before searching physicians answered 10 of 23 (43.5% questions accurately. For questions that were searched using clinician‐selected electronic resources, 18 (39.1% of the 46 answers were accurate before searching, while 19 (42.1% were accurate after searching. The difference of

  11. Removal of radiocobalt from aqueous solutions by kaolinite affected by solid content, pH, ionic strength, contact time and temperature

    International Nuclear Information System (INIS)

    Kan Li; Zhengjie Liu; Lei Chen; Yunhui Dong; Jun Hu; Chinese Academy of Sciences, Hefei

    2013-01-01

    The kaolinite sample was characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray powder diffraction, and was applied as adsorbent for the removal of radiocobalt ions from radioactive wastewater. The results demonstrated that the sorption of Co(II) was strongly dependent on pH and ionic strength at low pH values, and independent of pH and ionic strength at high pH values. The sorption of Co(II) was dominated by outer-sphere surface complexation or ion exchange at low pH values, whereas inner-sphere surface complexation was the main sorption mechanism at high pH values. The sorption isotherms were well described by Langmuir, Freundlich and Dubinin-Radushkevich models. The thermodynamic parameters (i.e., ΔGdeg, ΔSdeg, ΔHdeg) calculated from the temperature-dependent sorption isotherms indicated that the sorption of Co(II) on kaolinite was an endothermic and spontaneous process. The results of high sorption capacity of kaolinite suggested that the kaolinite sample was a suitable material for the preconcentration of Co(II) from large volumes of aqueous solutions and as backfill materials in nuclear waste management. (author)

  12. Mineralogical and crystallochemical transformations originated from thermal essays on ferruginous kaolinitic clays; Transformacoes mineralogicas e cristaloquimicas decorrentes dos ensaios termais em argilas cauliniticas ferruginosas

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, M.M.; Varajao, A.F.D.C.; Morales-Carrera, A.M.; Peralta-Sanchez, M.G.; Costa, G.M. da, E-mail: angelica@degeo.ufop.br [Universidade Federal de Ouro Preto, Campus Universitario, Morro do Cruzeiro s/n, Ouro Preto, MG (Brazil)

    2012-01-15

    Mineralogical and crystallochemical transformations of representative ferruginous kaolinitic clay samples were investigated in specimens burned at 800, 1000 and 1200 deg C. X-ray diffraction and differential thermal and thermogravimetric analyses showed that kaolinite was the predominant mineral in the raw samples. The Moessbauer spectroscopy results showed that the high iron content (22.5 wt.%), as determined by X-ray fluorescence, is related to the presence of goethite (18 wt.%) and hematite (16 wt.%). However, after Fe was extracted using a dithionite-citrate system buffered with sodium bicarbonate, a residue of this element (Fe{sup 3+} and Fe{sup 2+}) was found in the structure of the kaolinite. The sintering process showed the destruction of kaolinite, as well as the transformation of the goethite into hematite, the crystals growing as the temperature increases. The hematite crystal size at 1200 deg C is five times larger than in the raw sample. The mullite formation at 1000 deg C is comprised of a solid solution of Fe{sub 2}O{sub 3} and Al{sub 2}O{sub 3},which results in a resistant product with a higher thermal stability (author)

  13. Self-Paced Interactive Multimedia Courseware: A Learning Support Resource for Enhancing Electronic Theses and Dissertations Development

    Science.gov (United States)

    Essel, Harry Barton; Osei-Poku, Patrick; Tachie-Menson, Akosua; Opoku-Asare, Nana Afia

    2016-01-01

    Submission of Electronic Theses and Dissertations (ETDs) by postgraduate students has become a common phenomenon in learning environments globally. The purpose of ETDs is to train postgraduate students as knowledge workers in online publishing and also extend their skills beyond word processing. The challenge however, is that many postgraduate…

  14. Web Accessibility Issues for Higher & Further Education. EDNER (Formative Evaluation of the Distributed National Electronic Resource) Project. Issues Paper.

    Science.gov (United States)

    Manchester Metropolitan Univ. (England).

    This issues paper, sixth in a series of eight, is intended to distill formative evaluation questions on topics that are central to the development of the higher and further education information environment in the United Kingdom. In undertaking formative evaluation studies, the Formative Evaluation of the Distributed National Electronic Resource…

  15. Analyzing the Academic Research Trends by Using University Digital Resources: A Bibliometric Study of Electronic Commerce in China

    Science.gov (United States)

    Fatima, Anam; Abbas, Asad; Ming, Wan; Zaheer, Ahmad Nawaz; Akhtar, Masood-ul-Hassan

    2017-01-01

    Technology plays a vital role in every field of life especially in business and education. Electronic commerce (EC) begins in the year of 1991 right after internet was introduced for commercial use. It is known to be the 12th five years' plan (2011 to 2015) of Chinese Ministry of Industry and Information Technology. The main "objective"…

  16. Green Supply Chain Collaboration for Fashionable Consumer Electronics Products under Third-Party Power Intervention—A Resource Dependence Perspective

    OpenAIRE

    Jiuh-Biing Sheu

    2014-01-01

    Under third-party power intervention (TPPI), which increases uncertainty in task environments, complex channel power interplays and restructuring are indispensable among green supply chain members as they move toward sustainable collaborative relationships for increased viability and competitive advantage. From the resource dependence perspective, this work presents a novel conceptual model to investigate the influence of political and social power on channel power restructuring and induced ...

  17. Application of surface complexation modelling: Nickel sorption on quartz, manganese oxide, kaolinite and goethite, and thorium on silica

    International Nuclear Information System (INIS)

    Olin, M.; Lehikoinen, J.

    1997-12-01

    The study is a follow-up to a previous modelling task on mechanistic sorption. The experimental work has been carried out at the Laboratory of Radiochemistry, University of Helsinki (HYRL), and the sorption modelling was performed using the HYDRAQL code. Parameters taken from the open literature were employed in the modelling phase. The thermodynamic data for aqueous solutions were extracted from the EQ3/6 database and subsequently modified for HYDRAQL where necessary. The experimental data were obtained from five different experiments, four of which concerned the adsorption of nickel. The first experimental system was a mixture of Nilsiae quartz and manganese dioxide. In the second experiment, quartz was equilibrated with a fresh and saline groundwater simulant instead of an electrolyte solution. The third and fourth experiments dealt with nickel adsorption from an electrolyte solution onto goethite and kaolinite surfaces respectively. In the fifth experiment, adsorption of thorium onto a quartz surface was investigated

  18. Effect of the acid treatment conditions of kaolinite on etheramine adsorption: A comparative analysis using chemometric tools.

    Science.gov (United States)

    Leal, Paulo Vitor Brandão; Magriotis, Zuy Maria; Sales, Priscila Ferreira de; Papini, Rísia Magriotis; Viana, Paulo Roberto de Magalhães

    2017-07-15

    The present work evaluated the effect of the acid treatment conditions of natural kaolinite (NK) regarding its efficiency in removing etheramine. The treatment was conducted using sulfuric acid at the concentrations of 1 mol L -1 (KA-01), 2 mol L -1 (KA-02) and 5 mol L -1 (KA-05) at 85 °C. The obtained adsorbents were characterized by X-ray fluorescence, X-ray diffraction, N 2 adsorption/desorption isotherms, zeta potential analysis and infrared spectroscopy. The Response Surface Method was used to optimize adsorption parameters (initial concentration of etheramine, adsorbent mass and pH of the solution). The results, described by means of a central composite design, were adjusted to the quadratic model. Results revealed that the adsorption was more efficient at the etheramine concentration of 400 mg L -1 , pH 10 and adsorbent mass of 0.1 g for NK and 0.2 g for KA-01, KA-02 and KA-05. The sample KA-02 presented a significant increase of etheramine removal compared to the NK sample. The adsorption kinetics conducted under optimized conditions showed that the system reached the equilibrium in approximately 30 min. The kinetic data were better adjusted to the pseudo-second order model. The isotherm data revealed that the Sips model was the most adequate one. The calculation of E ads allowed to infer that the mechanism for etheramine removal in all the evaluated samples was chemisorption. The reuse tests showed that, after four uses, the efficiency of adsorbents in removing etheramine did not suffer significant modifications, which makes the use of kaolinite to treat effluents from the reverse flotation of iron ore feasible. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Share and share alike: encouraging the reuse of academic resources through the Scottish electronic Staff Development Library

    Directory of Open Access Journals (Sweden)

    Lorna M. Campbell

    2001-12-01

    Full Text Available The Scottish electronic Staff Development Library (http://www.sesdl.scotcit.acuk is an ongoing collaborative project involving the Universities of Edinburgh, Paisley and Strathclyde which has been funded by SHEFC as part of their current ScotCIT Programme (http:llwww.scotcit.ac.uk. This project is being developed in response to the increasing demand for flexible, high-quality staff development materials.

  20. Success factors for implementing and sustaining a mature electronic medical record in a low-resource setting: a case study of iSanté in Haiti.

    Science.gov (United States)

    deRiel, E; Puttkammer, N; Hyppolite, N; Diallo, J; Wagner, S; Honoré, J G; Balan, J G; Celestin, N; Vallès, J S; Duval, N; Thimothé, G; Boncy, J; Coq, N R L; Barnhart, S

    2018-03-01

    Electronic health information systems, including electronic medical records (EMRs), have the potential to improve access to information and quality of care, among other things. Success factors and challenges for novel EMR implementations in low-resource settings have increasingly been studied, although less is known about maturing systems and sustainability. One systematic review identified seven categories of implementation success factors: ethical, financial, functionality, organizational, political, technical and training. This case study applies this framework to iSanté, Haiti's national EMR in use in more than 100 sites and housing records for more than 750 000 patients. The author group, consisting of representatives of different agencies within the Haitian Ministry of Health (MSPP), funding partner the Centers for Disease Control and Prevention (CDC) Haiti, and implementing partner the International Training and Education Center for Health (I-TECH), identify successes and lessons learned according to the seven identified categories, and propose an additional cross-cutting category, sustainability. Factors important for long-term implementation success of complex information systems are balancing investments in hardware and software infrastructure upkeep, user capacity and data quality control; designing and building a system within the context of the greater eHealth ecosystem with a plan for interoperability and data exchange; establishing system governance and strong leadership to support local system ownership and planning for system financing to ensure sustainability. Lessons learned from 10 years of implementation of the iSanté EMR system are relevant to sustainability of a full range of increasingly interrelated information systems (e.g. for laboratory, supply chain, pharmacy and human resources) in the health sector in low-resource settings. © The Author 2017. Published by Oxford University Press in association with The London School of Hygiene

  1. Selection and Evaluation of Electronic Resources Elektronik Kaynakların Seçimi ve Değerlendirilmesi

    Directory of Open Access Journals (Sweden)

    Doğan Atılgan

    2009-12-01

    Full Text Available Publication boom and issues related to controlling and accession of printed sources have created some problems after World War II. Consequently, publishing industry has encountered the problem of finding possible solution for emerged situation. Industry of electronic publishing has started to improve with the rapid increase of the price of printed sources as well as the problem of publication boom. The first effects of electronic publishing were appeared on the academic and scholarly publications then electronic publishing became a crucial part of all types of publications. As a result of these developments, collection developments and service policies of information centers were also significantly changed. In this article, after a general introduction about selection and evaluation processes of electronic publications, the subscribed databases by a state and a privately owned university in Turkey and their usage were examined. İkinci dünya savaşından sonra görülen yayın patlaması, basılı kaynakların denetim ve erişiminde sorunlar yaşanmasına neden olmuştur. Bu da yayıncılık sektöründe yeni arayışlara yol açmıştır. 1980’li yıllardan sonra basılı yayın fiyatlarındaki hızlı artış da bu etmenlere eklenince elektronik yayıncılık sektörü gelişmeye başlamıştır. Öncelikle bilimsel ve akademik yayınlarla başlayan elektronik yayın günümüzde tüm yayın türlerini kapsamaktadır. Yayıncılıktaki bu gelişim bilgi merkezlerinin derme geliştirme ve hizmet politikalarını da önemli ölçüde değiştirmiştir. Bu çalışmada elektronik yayınların seçim, değerlendirme ve sağlama konularında genel bir girişten sonra bir devlet üniversitesinin bir de özel üniversitenin abone olduğu veritabanları ve bu veri tabanlarının kullanımının değerlendirilmesi yapılmaktadır.

  2. Utility of the electronic information resource UpToDate for clinical decision-making at bedside rounds.

    Science.gov (United States)

    Phua, J; See, K C; Khalizah, H J; Low, S P; Lim, T K

    2012-02-01

    Clinical questions often arise at daily hospital bedside rounds. Yet, little information exists on how the search for answers may be facilitated. The aim of this prospective study was, therefore, to evaluate the overall utility, including the feasibility and usefulness of incorporating searches of UpToDate, a popular online information resource, into rounds. Doctors searched UpToDate for any unresolved clinical questions during rounds for patients in general medicine and respiratory wards, and in the medical intensive care unit of a tertiary teaching hospital. The nature of the questions and the results of the searches were recorded. Searches were deemed feasible if they were completed during the rounds and useful if they provided a satisfactory answer. A total of 157 UpToDate searches were performed during the study period. Questions were raised by all ranks of clinicians from junior doctors to consultants. The searches were feasible and performed immediately during rounds 44% of the time. Each search took a median of three minutes (first quartile: two minutes, third quartile: five minutes). UpToDate provided a useful and satisfactory answer 75% of the time, a partial answer 17% of the time and no answer 9% of the time. It led to a change in investigations, diagnosis or management 37% of the time, confirmed what was originally known or planned 38% of the time and had no effect 25% of the time. Incorporating UpToDate searches into daily bedside rounds was feasible and useful in clinical decision-making.

  3. Heterogeneous reactions of dioctahedral smectites in illite-smectite and kaolinite-smectite mixed-layers: applications to clay materials for engineered barriers

    International Nuclear Information System (INIS)

    Meunier, A.; Proust, D.; Beaufort, D.; Lajudie, A.; Petit, J.-C.

    1992-01-01

    The clay materials selected for use in the engineered barriers of the French nuclear waste isolation programme are mainly composed of dioctahedral smectite, either bentonite of Wyoming type or kaolinite-smectites most often consist of randomly stacked layers with low and high charges. In the case of the Wyoming-type bentonite, these two differently charged layers do not react in the same way when subjected to hydrothermal alteration. Overall, the low-charge smectite layers react to form high-charge smectite layers + quartz + kaolinite. Then, fixing K ions, the high-charge smectite layers are transformed into illite-smectite mixed-layers (I/S) when the temperature conditions increase. A symmetrical process is observed in natural or experimental hydrothermal conditions when the high-charge smectite layers of I/S minerals react with quartz and/or kaolinite to produce low-charge smectite layers. The chemical properties of the bentonite-engineered barriers clearly depend on the low charge/high charge smectite layer proportion, which is in turn controlled by the temperature-dependent reactions in the vicinity of the waste disposal. Although there are fewer published data on the kaolinite-smectite mixed-layered minerals (K/S), a similar low charge-high charge reaction appears to affect their smectite component. The experimental alteration of K/S leads to the formation of a low-charge beidellite with an increase in the cation-exchange capacity and in the expandability of the clay material. Thus, the properties of the engineered barrier seems to be improved after hydrothermal alteration. (Author)

  4. Surface complexation modelling: Experiments on sorption of nickel on quartz, goethite and kaolinite and preliminary tests on sorption of thorium on quartz

    Energy Technology Data Exchange (ETDEWEB)

    Puukko, E.; Hakanen, M. [Univ. of Helsinki (Finland). Dept. of Chemistry. Lab. of Radiochemistry

    1997-09-01

    The aim of the work was to study the sorption behaviour of Ni on quartz, goethite and kaolinite at different pH levels and in different electrolyte solutions of different strength. In addition preliminary experiments were made to study the sorption of thorium on quartz. The MUS quartz and Nilsiae quartz were analysed for MnO{sub 2} by neutron activation analysis (NAA) and the experimental results were modelled with the HYDRAQL computer model. 9 refs.

  5. Impact of carbonate on the efficiency of heavy metal removal from kaolinite soil by the electrokinetic soil remediation method

    International Nuclear Information System (INIS)

    Ouhadi, V.R.; Yong, R.N.; Shariatmadari, N.; Saeidijam, S.; Goodarzi, A.R.; Safari-Zanjani, M.

    2010-01-01

    While the feasibility of using electrokinetics to decontaminate soils has been studied by several authors, the effects of soil composition on the efficiency of this method of decontamination has yet to be fully studied. This study focuses its attention on the effect of 'calcite or carbonate' (CaCO 3 ) on removal efficiency in electrokinetic soil remediation. Bench scale experiments were conducted on two soils: kaolinite and natural-soil of a landfill in Hamedan, Iran. Prescribed quantities of carbonates were mixed with these soils which were subsequently contaminated with zinc nitrate. After that, electrokinetic experiments were conducted to determine the efficiency of electrokinetic remediation. The results showed that an increase in the quantity of carbonate caused a noticeable increase on the contaminant retention of soil and on the resistance of soil to the contaminant removal by electrokinetic method. Because the presence of carbonates in the soil increases its buffering capacity, acidification is reduced, resulting in a decrease in the rate of heavy metal removed from the contaminant soil. This conclusion was validated by the evaluation of efficiency of electrokinetic method on a soil sample from the liner of a waste disposal site, with 28% carbonates.

  6. Impact of carbonate on the efficiency of heavy metal removal from kaolinite soil by the electrokinetic soil remediation method

    Energy Technology Data Exchange (ETDEWEB)

    Ouhadi, V.R., E-mail: vahidouhadi@yahoo.ca [Faculty of Engineering, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of); Yong, R.N. [RNY Geoenvironmental Research, North Saanich (Canada); Shariatmadari, N. [Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Saeidijam, S.; Goodarzi, A.R.; Safari-Zanjani, M. [Faculty of Engineering, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of)

    2010-01-15

    While the feasibility of using electrokinetics to decontaminate soils has been studied by several authors, the effects of soil composition on the efficiency of this method of decontamination has yet to be fully studied. This study focuses its attention on the effect of 'calcite or carbonate' (CaCO{sub 3}) on removal efficiency in electrokinetic soil remediation. Bench scale experiments were conducted on two soils: kaolinite and natural-soil of a landfill in Hamedan, Iran. Prescribed quantities of carbonates were mixed with these soils which were subsequently contaminated with zinc nitrate. After that, electrokinetic experiments were conducted to determine the efficiency of electrokinetic remediation. The results showed that an increase in the quantity of carbonate caused a noticeable increase on the contaminant retention of soil and on the resistance of soil to the contaminant removal by electrokinetic method. Because the presence of carbonates in the soil increases its buffering capacity, acidification is reduced, resulting in a decrease in the rate of heavy metal removed from the contaminant soil. This conclusion was validated by the evaluation of efficiency of electrokinetic method on a soil sample from the liner of a waste disposal site, with 28% carbonates.

  7. Highly efficient fluoride adsorption from aqueous solution by nepheline prepared from kaolinite through alkali-hydrothermal process.

    Science.gov (United States)

    Wang, Hao; Feng, Qiming; Liu, Kun; Li, Zishun; Tang, Xuekun; Li, Guangze

    2017-07-01

    A direct alkali-hydrothermal induced transformation process was adopted to prepare nepheline from raw kaolinite (shortened form RK in this paper) and NaOH solution in this paper. Structure and morphology characterizations of the synthetic product showed that the nepheline possessed high degree of crystallinity and uniform surface morphology. Specific surface area of nepheline is 18 m 2 /g, with a point of zero charge at around pH 5.0-5.5. The fluoride (F - ions) adsorption by the synthetic nepheline (shortened form SN in this paper) from aqueous solution was also investigated under different experimental conditions. The adsorption process well matched the Langmuir isotherm model with an amazing maximum adsorption capacity of 183 mg/g at 323 K. The thermodynamic parameters (ΔG 0 , ΔH 0 , and ΔS 0 ) for adsorption on SN were also determined from the temperature dependence. The adsorption capacities of fluoride on SN increased with increasing of temperature and initial concentration. Initial pH value also had influence on adsorption process. Adsorption of fluoride was rapidly increased in 5-60 min and thereafter increased slowly to reach the equilibrium in about 90-180 min under all conditions. The adsorption followed a pseudo-second order rate law. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Sensors properties of an alkylamine-intercalated kaolinite material towards the voltammetric preconcentration of [Ru(CN)6]4- at a clay-modified electrode

    Energy Technology Data Exchange (ETDEWEB)

    Tonle, I.K. [Ottawa Univ., ON (Canada). Dept. of Chemistry, Center for Catalysis Research and Innovation; Yanoude Univ. (Cameroon). Laboratoire de Chimie Analytique, Faculte des Sciences; Dschang Univ. (Cameroon). Dept. de Chimie; Bouwe, B.; Rose, G.; Ngameni, E. [Yanoude Univ. (Cameroon). Laboratoire de Chimie Analytique, Faculte des Sciences; Detellier, C. [Yanoude Univ. (Cameroon). Laboratoire de Chimie Analytique, Faculte des Sciences

    2008-07-01

    This study discussed the sensor properties of a kaolinite material in relation to the voltammetric preconcentration of ruthenium (Ru) anions in a clay-modified electrode. An organoclay was intercalated at room temperature with a layer of hexylamine. Dimethylsulfoxide (DMSO) was intercalated between the clay layers and displaced in wet conditions by the akylamine. The modified clay was then characterized using X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The analyses confirmed the incorporation of the hexylamine between the kaolinite platelets. The organokaolinite was then studied for use as a preconcentration agent when coated on the active surface of a glassy carbon electrode for the accumulation of [Ru(CN)6]4- anions in a hydrochloric acid medium. Factors that influenced the conductivity of the film and the diffusion of the electroactive species within the film included the concentration of the electrolyte, and the redox probe. The study showed that kaolinite can be used as a material in electrochemical sensors.

  9. Comprehensive evaluation of electronic medical record system use and user satisfaction at five low-resource setting hospitals in ethiopia.

    Science.gov (United States)

    Tilahun, Binyam; Fritz, Fleur

    2015-05-25

    Electronic medical record (EMR) systems are increasingly being implemented in hospitals of developing countries to improve patient care and clinical service. However, only limited evaluation studies are available concerning the level of adoption and determinant factors of success in those settings. The objective of this study was to assess the usage pattern, user satisfaction level, and determinants of health professional's satisfaction towards a comprehensive EMR system implemented in Ethiopia where parallel documentation using the EMR and the paper-based medical records is in practice. A quantitative, cross-sectional study design was used to assess the usage pattern, user satisfaction level, and determinant factors of an EMR system implemented in Ethiopia based on the DeLone and McLean model of information system success. Descriptive statistical methods were applied to analyze the data and a binary logistic regression model was used to identify determinant factors. Health professionals (N=422) from five hospitals were approached and 406 responded to the survey (96.2% response rate). Out of the respondents, 76.1% (309/406) started to use the system immediately after implementation and user training, but only 31.7% (98/309) of the professionals reported using the EMR during the study (after 3 years of implementation). Of the 12 core EMR functions, 3 were never used by most respondents, and they were also unaware of 4 of the core EMR functions. It was found that 61.4% (190/309) of the health professionals reported over all dissatisfaction with the EMR (median=4, interquartile range (IQR)=1) on a 5-level Likert scale. Physicians were more dissatisfied (median=5, IQR=1) when compared to nurses (median=4, IQR=1) and the health management information system (HMIS) staff (median=2, IQR=1). Of all the participants, 64.4% (199/309) believed that the EMR had no positive impact on the quality of care. The participants indicated an agreement with the system and information

  10. Randomized Controlled Trial of Electronic Care Plan Alerts and Resource Utilization by High Frequency Emergency Department Users with Opioid Use Disorder

    Directory of Open Access Journals (Sweden)

    Niels Rathlev, MD

    2016-01-01

    Full Text Available Introduction: There is a paucity of literature supporting the use of electronic alerts for patients with high frequency emergency department (ED use. We sought to measure changes in opioid prescribing and administration practices, total charges and other resource utilization using electronic alerts to notify providers of an opioid-use care plan for high frequency ED patients. Methods: This was a randomized, non-blinded, two-group parallel design study of patients who had 1 opioid use disorder and 2 high frequency ED use. Three affiliated hospitals with identical electronic health records participated. Patients were randomized into “Care Plan” versus “Usual Care groups”. Between the years before and after randomization, we compared as primary outcomes the following: 1 opioids (morphine mg equivalents prescribed to patients upon discharge and administered to ED and inpatients; 2 total medical charges, and the numbers of; 3 ED visits, 4 ED visits with advanced radiologic imaging (computed tomography [CT] or magnetic resonance imaging [MRI] studies, and 5 inpatient admissions. Results: A total of 40 patients were enrolled. For ED and inpatients in the “Usual Care” group, the proportion of morphine mg equivalents received in the post-period compared with the pre-period was 15.7%, while in the “Care Plan” group the proportion received in the post-period compared with the pre-period was 4.5% (ratio=0.29, 95% CI [0.07-1.12]; p=0.07. For discharged patients in the “Usual Care” group, the proportion of morphine mg equivalents prescribed in the post-period compared with the pre-period was 25.7% while in the “Care Plan” group, the proportion prescribed in the post-period compared to the pre-period was 2.9%. The “Care Plan” group showed an 89% greater proportional change over the periods compared with the “Usual Care” group (ratio=0.11, 95% CI [0.01-0.092]; p=0.04. Care plans did not change the total charges, or, the numbers

  11. There is a Relationship between Resource Expenditures and Reference Transactions in Academic Libraries. A Review of: Dubnjakovic, A. (2012. Electronic resource expenditure and the decline in reference transaction statistics in academic libraries. Journal of Academic Librarianship, 38(2, 94-100. doi:10.1016/j.acalib.2012.01.001

    Directory of Open Access Journals (Sweden)

    Annie M. Hughes

    2013-03-01

    Full Text Available Objective – To provide an analysis of the impact of expenditures on electronic resourcesand gate counts on the increase or decrease in reference transactions.Design – Analysis of results of existing survey data from the National Center for Educational Statistics (NCES 2006 Academic Library Survey(ALS.Setting – Academic libraries in the United States.Subjects – 3925 academic library respondents.Methods – The author chose to use survey data collected from the 2006 ALS conducted bythe NCES. The survey included data on various topics related to academic libraries, but in the case of this study, the author chose to analyze three of the 193 variables included. The three variables: electronic books expenditure, computer hardware and software, and expenditures on bibliographic utilities, were combined into one variable called electronic resource expenditure. Gate counts were also considered as a variable. Electronic resource expenditure was also split as a variable into three groups: low, medium, and high. Multiple regression analysis and general linear modeling, along with tests of reliability, were employed. Main Results – The author determined that low, medium, and high spenders with regard to electronic resources exhibited differences in gate counts, and gate counts have an effect on reference transactions in any given week. Gate counts tend to not have much of an effect on reference transactions for the higher spenders, and higher spenders tend to have a higher number of reference transactions overall. Low spenders have lower gate counts and also a lower amount of reference transactions.Conclusion – The findings from this study show that academic libraries spending more on electronic resources also tend to have an increase with regard to reference transactions. The author also concludes that library spaces are no longer the determining factor with regard to number of reference transactions. Spending more on electronic resources is

  12. Global application of disorders of sex development-related electronic resources: e-learning, e-consultation and e-information sharing.

    Science.gov (United States)

    Muscarella, Miriam; Kranenburg-van Koppen, Laura; Grijpink-van den Biggelaar, Kalinka; Drop, Stenvert L S

    2014-01-01

    The past 20 years have seen proliferation of electronic (e) resources that promote improved understanding of disorders of sex development (DSD): e-learning for physicians and trainees, e-consultation between clinicians, and e-information for families and affected individuals. Recent e-learning advances have emerged from the European Society for Pediatric Endocrinology's online learning portal for current physicians and trainees. Developed with attention to developing clinical competencies incorporating learning theory, and presenting material that represents international best practice, this e-learning portal offers advances in training, making information more accessible for clinicians and trainees. Multiple levels of instruction, authentic case examples, collaborative forums for physicians and trainees, individualized feedback and user-friendly tools represent advances in trainee and physician learning that can take place in any location. e-consultation is an emerging tool that aims to connect physicians with specialists experienced in DSD care. Although it faces logistical challenges, e-consultation carries the potential to improve DSD care, especially in remote areas with limited access to DSD specialists. e-information for families and patients of all ages is widely accessible online, often with focus on DSD biology, medical care, and psychological and social support. e-information tools aid self-management and support of those affected by DSD. Efforts to improve these resources should aim to map information to individual users, incorporate optimally clear nomenclature, and continue as a 'shared enterprise' of clinicians, affected individuals, families and researchers. Improving the quality of DSD-related e-learning and e-information and developing e-consultation carries the potential to transform DSD care and support for patients, families and physicians worldwide. © 2014 S. Karger AG, Basel.

  13. Ranking Medical Terms to Support Expansion of Lay Language Resources for Patient Comprehension of Electronic Health Record Notes: Adapted Distant Supervision Approach.

    Science.gov (United States)

    Chen, Jinying; Jagannatha, Abhyuday N; Fodeh, Samah J; Yu, Hong

    2017-10-31

    Medical terms are a major obstacle for patients to comprehend their electronic health record (EHR) notes. Clinical natural language processing (NLP) systems that link EHR terms to lay terms or definitions allow patients to easily access helpful information when reading through their EHR notes, and have shown to improve patient EHR comprehension. However, high-quality lay language resources for EHR terms are very limited in the public domain. Because expanding and curating such a resource is a costly process, it is beneficial and even necessary to identify terms important for patient EHR comprehension first. We aimed to develop an NLP system, called adapted distant supervision (ADS), to rank candidate terms mined from EHR corpora. We will give EHR terms ranked as high by ADS a higher priority for lay language annotation-that is, creating lay definitions for these terms. Adapted distant supervision uses distant supervision from consumer health vocabulary and transfer learning to adapt itself to solve the problem of ranking EHR terms in the target domain. We investigated 2 state-of-the-art transfer learning algorithms (ie, feature space augmentation and supervised distant supervision) and designed 5 types of learning features, including distributed word representations learned from large EHR data for ADS. For evaluating ADS, we asked domain experts to annotate 6038 candidate terms as important or nonimportant for EHR comprehension. We then randomly divided these data into the target-domain training data (1000 examples) and the evaluation data (5038 examples). We compared ADS with 2 strong baselines, including standard supervised learning, on the evaluation data. The ADS system using feature space augmentation achieved the best average precision, 0.850, on the evaluation set when using 1000 target-domain training examples. The ADS system using supervised distant supervision achieved the best average precision, 0.819, on the evaluation set when using only 100 target

  14. Impact of two interventions on timeliness and data quality of an electronic disease surveillance system in a resource limited setting (Peru: a prospective evaluation

    Directory of Open Access Journals (Sweden)

    Quispe Jose A

    2009-03-01

    Full Text Available Abstract Background A timely detection of outbreaks through surveillance is needed in order to prevent future pandemics. However, current surveillance systems may not be prepared to accomplish this goal, especially in resource limited settings. As data quality and timeliness are attributes that improve outbreak detection capacity, we assessed the effect of two interventions on such attributes in Alerta, an electronic disease surveillance system in the Peruvian Navy. Methods 40 Alerta reporting units (18 clinics and 22 ships were included in a 12-week prospective evaluation project. After a short refresher course on the notification process, units were randomly assigned to either a phone, visit or control group. Phone group sites were called three hours before the biweekly reporting deadline if they had not sent their report. Visit group sites received supervision visits on weeks 4 & 8, but no phone calls. The control group sites were not contacted by phone or visited. Timeliness and data quality were assessed by calculating the percentage of reports sent on time and percentage of errors per total number of reports, respectively. Results Timeliness improved in the phone group from 64.6% to 84% in clinics (+19.4 [95% CI, +10.3 to +28.6]; p Conclusion Regular phone reminders significantly improved timeliness of reports in clinics and ships, whereas supervision visits led to improved data quality only among clinics. Further investigations are needed to establish the cost-effectiveness and optimal use of each of these strategies.

  15. Thermodynamic and Kinetic Aspects of the Dissolution of Quartz-Kaolinite Mixtures by Alkalis Aspects thermodynamiques et cinétiques de la dissolution des mélanges quartz-kaolinite par les alcalis

    Directory of Open Access Journals (Sweden)

    Labrid J.

    2006-11-01

    'ensemble des données expérimentales indique que, outre l'adsorption de l'acide silicique Si(OH4 et de l'ion (***, il est nécessaire de faire appel à un autre mécanisme d'inhibition que l'on suppose joué par l'analcime adsorbée. Il est raisonnable de penser qu'avant précipitation, l'analcime est fixée sur la surface quartzeuse qui agit comme support à la nucléation. Ces hypothèses conduisent à un nouveau schéma cinétique qui inclut ces différents mécanismes d'adsorption. Les concentrations calculées en silicium et en aluminium solubilisés s'accordent bien aux données expérimentales pour des temps de réaction allant jusqu'à 3 000 heures. Les études faites sur la kaolinite ont montré que ce minéral est aussi capable d'adsorber l'aluminium, vraisemblablement sous la forme d'ion (***. Une procédure de traitement de l'argile est proposée en préalable à toute étude cinétique afin d'éliminer les espèces adsorbées. Dans ces conditions, la dissolution de la kaolinite est congruente. Par analogie avec la dissolution du quartz, et compte tenu de la structure minéralogique de la kaolinite, nous avons proposé un schéma cinétique de dissolution de l'argile qui décrit la co-adsorption des espèces Si(OH4 et (***, préalablement à la formation du cristal. La validité de ces mécanismes cinétiques a été examinée en menant des expériences de dissolution de mélanges de quartz et de kaolinite. La modélisation de l'attaque a été faite en prenant en compte les processus d'adsorption et de précipitation observés. Le modèle adopté qui traduit le couplage des processus élémentaires de dissolution permet le calcul des concentrations en aluminium et silicium solubilisés. La comparaison avec l'expérience indique qu'il est nécessaire d'attribuer à l'argile une réactivité notablement supérieure à celle déterminée avec le minéral isolé. Il est suggéré que le sable pourrait jouer un rôle sur l'état de dispersion de l'argile avec corr

  16. Unraveling climatic changes from intra-profile variation in oxygen and hydrogen isotopic composition of goethite and kaolinite in laterites: An integrated study from Yaou, French Guiana

    Science.gov (United States)

    Girard, Jean-Pierre; Freyssinet, Philippe; Chazot, Gilles

    2000-02-01

    An integrated study of O and H isotopes in the lateritic profile of Yaou, French Guiana, was undertaken to investigate the usefulness of stable isotopes as tracers of climatic changes in continental environments. The studied profile is composed of a 27 m thick saprolite, mostly developed in the past under wet-and-dry tropical climate in association with a duricrust, overlain by a 3 m thick yellow latosol formed more recently under present equatorial hot and humid climate. δ 18O-δD values determined for weathering goethite (pseudomorphs after pyrite) and kaolinite (microcrystalline clay groundmass) throughout the 30 m deep profile reflect formation temperatures consistent with present (25°C) and realistic past climatic temperatures (20°C-30°C), indicating that weathering minerals formed in isotopic equilibrium with their genetic environment and were not subjected to significant isotope exchange after formation. A distinct shift downward (2‰ for δ 18O, 15‰ for δD) from low to high δ 18O-δD values occurs around 20 m depth in the saprolite. It is interpreted as recording the change from the past tropical to the present equatorial climate. Goethite and kaolinite in the 5-10 m thick saprolite interval immediately above the active basement weathering front are in isotopic equilibrium with modern water and must have formed under present equatorial-humid conditions. In contrast, goethite and kaolinite found higher up in the saprolite and in the duricrust formed in the past under tropical wet and dry climate from waters distinctly depleted in 18O and D relative to modern water. The marked depletion of paleo-meteoric water at Yaou most likely reflects a more contrasted or "monsoonal" character of the ancient tropical climate. The present study shows that ancient weathering minerals in lateritic profiles preserve their δ 18O-δD values and carry a time signal. The time signal is best expressed in minerals formed rapidly at the weathering front and not subjected

  17. Unraveling climatic changes from intraprofile variation in oxygen and hydrogen isotopic composition of goethite and kaolinite in laterites: An integrated study from Yaou, French Guiana

    Energy Technology Data Exchange (ETDEWEB)

    Girard, J.P.; Freyssinet, P.; Chazot, G.

    2000-02-01

    An integrated study of O and H isotopes in the latertic profile of Yaou, French Guiana, was undertaken to investigate the usefulness of stable isotopes as tracers of climatic changes in continental environments. The studied profile is composed of a 27 m thick saprolite, mostly developed in the past under wet-and-dry tropical climate in association with a duricrust, overlain by a 3 m thick yellow latosol formed more recently under present equatorial hot and humid climate. {delta}{sup 18}O-{delta}D values determined for weathering goethite (pseudomorphs after pyrite) and kaolinite (microcrystalline clay groundmass) throughout the 30 m deep profile reflect formation temperatures consistent with present (25 C) and realistic past climatic temperatures (20 C--30 C), indicating that weathering minerals formed in isotopic equilibrium with their genetic environment and were not subjected to significant isotope exchange after formation. A distinct shift downward from low to high {delta}{sup 18}O-{delta}D values occurs around 20 m depth in the saprolite. It is interpreted as recording the change from the past tropical to the present equatorial climate. Goethite and kaolinite in the 5--10 m thick saprolite interval immediately above the active basement weathering front are in isotopic equilibrium with modern water and must have formed under present equatorial-humid conditions. In contrast, goethite and kaolinite found higher up on the saprolite and in the duricrust formed in the past under tropical wet and dry climate from waters distinctly depleted in {sup 18}O and D relative to modern water. The marked depletion of paleo-meteoric water at Yaou most likely reflects a more contrasted or monsoonal character of the ancient tropical climate. The present study shows that ancient weathering minerals in lateritic profiles preserve their {delta}{sup 18}O-{delta}D values and carry a time signal. The time signal is best expressed in minerals formed rapidly at the weathering front and

  18. Online Resources

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Online Resources. Journal of Genetics. Online Resources. Volume 97. 2018 | Online resources. Volume 96. 2017 | Online resources. Volume 95. 2016 | Online resources. Volume 94. 2015 | Online resources. Volume 93. 2014 | Online resources. Volume 92. 2013 | Online resources ...

  19. Increase in Ice Nucleation Efficiency of Feldspars, Kaolinite and Mica in Dilute NH3 and NH4+-containing Solutions

    Science.gov (United States)

    Kumar, A.; Marcolli, C.; Luo, B.; Krieger, U. K.; Peter, T.

    2017-12-01

    Semivolatile species present in the atmosphere are prone to adhere to mineral dust particle surfaces during long range transport, and could potentially change the particle surface properties and its ice nucleation (IN) efficiency. Immersion freezing experiments were performed with microcline (K-feldspar), known to be highly IN active, suspended in aqueous solutions of ammonia, (NH4)2SO4, NH4HSO4, NH4NO3, NH4Cl, Na2SO4, H2SO4, K2SO4 and KCl to investigate the effect of solutes on the IN efficiency. Freezing of emulsified droplets investigated with a differential scanning calorimeter (DSC) showed that the heterogeneous ice nucleation temperatures deviate from the water activity-based IN theory, describing heterogeneous ice nucleation temperatures as a function of solution water activity by a constant offset with respect to the ice melting point curve (Zobrist et al. 2008). IN temperatures enhanced up to 4.5 K were observed for very dilute NH3 and NH4+-containing solutions while a decrease was observed as the concentration was further increased. For all solutes with cations other than NH4+, the IN efficiency decreased. An increase of the IN efficiency in very dilute NH3 and NH4+-containing solutions followed by a decrease with increasing concentration was also observed for sanidine (K-feldspar) and andesine (Na/Ca-feldspar). This is an important indication towards specific chemical interactions between solutes and the feldspar surface which is not captured by the water activity-based IN theory. A similar trend is present but less pronounced in case of kaolinite and mica, while quartz is barely affected. We hypothesize that the hydrogen bonding of NH3 molecules with surface -OH groups could be the reason for the enhanced freezing temperatures in dilute ammonia and ammonium containing solutions as they could form an ice-like overlayer providing hydrogen bonding groups for ice to nucleate on top of it. This implies to possibilities of enhanced IN efficiency, especially

  20. Interactive Electronic Decision Trees for the Integrated Primary Care Management of Febrile Children in Low Resource Settings - Review of existing tools.

    Science.gov (United States)

    Keitel, Kristina; D'Acremont, Valérie

    2018-04-20

    The lack of effective, integrated diagnostic tools pose a major challenge to the primary care management of febrile childhood illnesses. These limitations are especially evident in low-resource settings and are often inappropriately compensated by antimicrobial over-prescription. Interactive electronic decision trees (IEDTs) have the potential to close these gaps: guiding antibiotic use and better identifying serious disease. This narrative review summarizes existing IEDTs, to provide an overview of their degree of validation, as well as to identify gaps in current knowledge and prospects for future innovation. Structured literature review in PubMed and Embase complemented by google search and contact with developers. Six integrated IEDTs were identified: three (eIMCI, REC, and Bangladesh digital IMCI) based on Integrated Management of Childhood Illnesses (IMCI); four (SL eCCM, MEDSINC, e-iCCM, and D-Tree eCCM) on Integrated Community Case Management (iCCM); two (ALMANACH, MSFeCARE) with a modified IMCI content; and one (ePOCT) that integrates novel content with biomarker testing. The types of publications and evaluation studies varied greatly: the content and evidence-base was published for two (ALMANACH and ePOCT), ALMANACH and ePOCT were validated in efficacy studies. Other types of evaluations, such as compliance, acceptability were available for D-Tree eCCM, eIMCI, ALMANACH. Several evaluations are still ongoing. Future prospects include conducting effectiveness and impact studies using data gathered through larger studies to adapt the medical content to local epidemiology, improving the software and sensors, and Assessing factors that influence compliance and scale-up. IEDTs are valuable tools that have the potential to improve management of febrile children in primary care and increase the rational use of diagnostics and antimicrobials. Next steps in the evidence pathway should be larger effectiveness and impact studies (including cost analysis) and

  1. Library resources on the Internet

    Science.gov (United States)

    Buchanan, Nancy L.

    1995-07-01

    Library resources are prevalent on the Internet. Library catalogs, electronic books, electronic periodicals, periodical indexes, reference sources, and U.S. Government documents are available by telnet, Gopher, World Wide Web, and FTP. Comparatively few copyrighted library resources are available freely on the Internet. Internet implementations of library resources can add useful features, such as full-text searching. There are discussion lists, Gophers, and World Wide Web pages to help users keep up with new resources and changes to existing ones. The future will bring more library resources, more types of library resources, and more integrated implementations of such resources to the Internet.

  2. Obtention of the cation exchange capacity of a natural kaolinite with radioactive tracers; Obtencion de la capacidad de intercambio cationico de una kaolinita natural con trazadores radioactivos

    Energy Technology Data Exchange (ETDEWEB)

    Uribe I, A.; Badillo A, V.E. [Universidad Autonoma de Zacatecas, 98000 Zacatecas (Mexico); Monroy G, F. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: Adrya81@hotmail.com

    2005-07-01

    One of the more used techniques for the elimination of the heavy metals present in water systems is to use adsorbent mineral phases like zeolites and clays, among others. The clays are able to exchange easily the fixed ions in the external surface of its crystals or well the ions present in the interlaminar spaces of the structures, for other existent ones in the encircling aqueous solutions for that the Cation exchange capacity (CIC) is defined as the sum of all the cations exchange that a mineral can possess independent to the physicochemical conditions. The CIC is equal to the measure of the total of negative charges of the mineral by mass of the solid (meq/g). In this investigation work, the value of the CIC equal to 2.5 meq/100 g is obtained, of a natural kaolinite from the State of Hidalgo studying the retention of the sodium in the kaolinite with the aid of the radioactive isotope {sup 24} Na and of the selective electrodes technique, making vary the pH value. So is experimentally demonstrated that the CIC is an intrinsic property of the mineral independent of the pH value of the solution and of the charges origin. (Author)

  3. Effects of network dissolution changes on pore-to-core upscaled reaction rates for kaolinite and anorthite reactions under acidic conditions

    KAUST Repository

    Kim, Daesang

    2013-11-01

    We have extended reactive flow simulation in pore-network models to include geometric changes in the medium from dissolution effects. These effects include changes in pore volume and reactive surface area, as well as topological changes that open new connections. The computed changes were based upon a mineral map from an X-ray computed tomography image of a sandstone core. We studied the effect of these changes on upscaled (pore-scale to core-scale) reaction rates and compared against the predictions of a continuum model. Specifically, we modeled anorthite and kaolinite reactions under acidic flow conditions during which the anorthite reactions remain far from equilibrium (dissolution only), while the kaolinite reactions can be near-equilibrium. Under dissolution changes, core-scale reaction rates continuously and nonlinearly evolved in time. At higher injection rates, agreement with predictions of the continuum model degraded significantly. For the far-from-equilibrium reaction, our results indicate that the ability to correctly capture the heterogeneity in dissolution changes in the reactive mineral surface area is critical to accurately predict upscaled reaction rates. For the near-equilibrium reaction, the ability to correctly capture the heterogeneity in the saturation state remains critical. Inclusion of a Nernst-Planck term to ensure neutral ionic currents under differential diffusion resulted in at most a 9% correction in upscaled rates.

  4. Herpes - resources

    Science.gov (United States)

    Genital herpes - resources; Resources - genital herpes ... following organizations are good resources for information on genital herpes : March of Dimes -- www.marchofdimes.org/complications/sexually- ...

  5. The Use of Quality Benchmarking in Assessing Web Resources for the Dermatology Virtual Branch Library of the National electronic Library for Health (NeLH)

    OpenAIRE

    Boulos, MN Kamel; Roudsari, AV; Gordon, C; Gray, JA Muir

    2001-01-01

    Background In 1998, the U.K. National Health Service Information for Health Strategy proposed the implementation of a National electronic Library for Health to provide clinicians, healthcare managers and planners, patients and the public with easy, round the clock access to high quality, up-to-date electronic information on health and healthcare. The Virtual Branch Libraries are among the most important components of the National electronic Library for Health . They aim at creating online kno...

  6. Analysis on Current Situation and Countermeasure of Domestic Electronic Commerce Logistics in the Internet Age——Based on Resource Dependence Theory

    Directory of Open Access Journals (Sweden)

    Zhang Jiapeng

    2017-01-01

    Full Text Available This paper analyzes the status of electric business logistics in the current Internet era in China, and combines the SWOT analysis with AHP to do the empirical analysis, then puts forward the countermeasure that the electric business logistics resource should be shared based on the resource dependence theory. Through the empirical analysis, it is found that the disadvantages and opportunities of the logistics status are important in the Internet era.The resource sharing strategy based on the resource dependence theory is more scientific. The rational use of Internet technology in electric business logistics industry can achieve “sharing”. It is of great significance for its balanced development, intelligent development and optimization and development.

  7. Efeito da adição de fonolito na sinterização de argila caulinítica Effect of phonolite addition on sintering kaolinitic clay

    Directory of Open Access Journals (Sweden)

    P. M. Andrade

    2005-12-01

    Full Text Available Este trabalho tem por objetivo avaliar o comportamento de queima de uma argila caulinítica incorporada com fonolito visando à obtenção de revestimento cerâmico prensado do tipo semiporoso. Foram preparadas composições com adição de fonolito a uma argila caulinítica nas proporções de 20 e 40% em peso. Para efeito comparativo, avaliou-se uma massa cerâmica industrial proveniente do pólo cerâmico de Santa Gertrudes. Foram preparados corpos de prova cilíndricos por prensagem uniaxial a 25 MPa para queima em temperaturas variando de 1050 a 1200 ºC. Nas amostras queimadas, foram realizados ensaios tecnológicos para determinação da retração linear e absorção de água em função da temperatura de queima. A avaliação microestrutural das composições estudadas foi realizada por difração de raios X e microscopia eletrônica de varredura. Os resultados mostraram que a adição de fonolito melhora significativamente a sinterização da argila caulinítica, sobretudo, em temperaturas acima de 1150 ºC, onde ocorre uma redução brusca da porosidade. Apesar do maior teor de óxidos alcalinos em comparação com uma massa industrial de revestimento cerâmico, as misturas argila/fonolito só alcançaram uma absorção de água de 10% , máxima para revestimentos semiporosos, em temperaturas cerca de 80 ºC superior à massa industrial.This work had as its objective to evaluate the firing behavior of a kaolinitic clay incorporated with phonolite aiming at semiporous pressed ceramic tiles. Compositions were prepared with addition of 20 and 40 wt.% of phonolite to a kaolinitic clay. For comparison, an industrial ceramic body from Santa Gertrudes, State of S. Paulo, was also evaluated. Cylindrical specimens were prepared by uniaxial pressure at 25 MPa followed by firing at temperatures varying from 1050 to 1200 ºC. The fired specimens were submitted to the following tests: linear shrinkage and water absorption as function of the firing

  8. Combination of multi-scale and multi-edge X-ray spectroscopy for investigating the products obtained from the interaction between kaolinite and metallic iron in anoxic conditions at 90 °C

    Science.gov (United States)

    Rivard, Camille; Montargès-Pelletier, Emmanuelle; Vantelon, Delphine; Pelletier, Manuel; Karunakaran, Chithra; Michot, Laurent J.; Villieras, Frédéric; Michau, Nicolas

    2013-02-01

    In the context of radioactive waste repository in geological formation, kaolinite-metallic iron interaction in chlorine solution was conducted in batch experiments, under anoxic conditions at 90 °C during 9 months. After a mineralogical characterization at a global scale, products were analyzed at the micrometer and nanometer scales by X-ray absorption spectroscopic techniques (XAS and STXM). Absorption at Al, Si and Fe edges was investigated to have a complete overview of the distribution and status of constituting elements. Whereas Si K-edge results do not evidence significant evolution of silicon status, investigations at Al K-edge and Fe L-edges demonstrate variations at aggregate and particle scales of IVAl:VIAl and Fe2+:Fe3+ ratios. Spectroscopic data evidence the systematic crystallization of Fe-serpentines onto the remaining particles of kaolinite and the absence of pure species (kaolinite or Fe-serpentines). Combination of spatially resolved spectroscopic analyses and TEM-EDXS elemental distribution aims to calculate unit cell formulae of Fe-serpentines layers and abundance of each species in mixed particles. For most of the investigated particles, results reveal that the variations of particles composition are directly linked to the relative contributions of kaolinite and Fe-berthierine in mixed particles. However, for some particles, microscale investigations evidence crystallization of two other Fe-serpentines species, devoid of aluminum, cronstedtite and greenalite.

  9. Adsorption of Cs+, Ni2+ and lanthanides onto a kaolinite and Na-montmorillonite up to 1500C: an experimental and modeling study

    International Nuclear Information System (INIS)

    Tertre, E.

    2005-10-01

    The motivation for this study is to assess the temperature effect on the clay minerals sorption properties. Sorption and desorption of Cs + , Ni 2+ et Ln 3+ onto a montmorillonite and a kaolinite were performed by batch experiments between 25 and 150 C, and in different pH and ionic strengths conditions. Sorption enthalpies varying between 0 and 80 kJ/mol were then calculated. For europium, surface spectroscopic analyses confirmed that the mechanism involved is adsorption, including at 150 C. Moreover, this method allowed us to obtain qualitatively the different adsorption equilibrium occurring during the reaction. An acid/base study of the clay surfaces was performed in order to assess the temperature effect on the surface charge of these minerals. Then, a surface complexation model including edge sites and structural sites was proposed to interpret the acid/base data and the europium sorption data. (author)

  10. How Students Learn: Ways of Thinking about "Good Learning" in HE. EDNER (Formative Evaluation of the Distributed National Electronic Resource) Project. Issues Paper.

    Science.gov (United States)

    Manchester Metropolitan Univ. (England).

    This issues paper, one of a series of eight, is intended to distill formative evaluation questions on topics that are central to the development of the higher and further education information environment in the United Kingdom. The topic of this first issues paper is a conceptual framework that can help members of a project (information resource)…

  11. 大學圖書館電子資源之需求分析與行銷策略之研究 A Study of Demands Analysis and Marketing Strategy of Electronic Resources in University Library

    Directory of Open Access Journals (Sweden)

    Huang-Yu Liu

    2008-03-01

    Full Text Available 電子資源的出現,使得知識載體有了新的突破,提高了使用者的便利性與即時性。對於圖書館而言,如何使電子資源的使用效益達到最高,必須思考一套有效的行銷策略。電子資源行銷概念應以讀者為導向,尊重讀者的資訊需求,並利用各種宣傳技巧,行銷電子資源,使圖書館能提供更完善的服務。本研究之目的旨在探討讀者的使用需求及電子資源的推廣策略,以獲致最有效益的行銷方式。研究對象以開南大學日間部四學院(商學院、運輸觀光學院、資訊學院、人文社會學院)學生為樣本,佐以缺口分析模型為分析架構,藉以找出個案中讀者/學生對於電子資源使用的真實需求,並進而歸納出提供服務的大學圖書館在其推廣或行銷服務上可有的因應策略。The emergence of electronic resources has made new breakthrough in knowledge carriers because of their ease of use, instant availability, and the characteristic of no time and space constraints. For public libraries to achieve maximum efficiency in its electronic resources, it is necessary to seek the most effective marketing strategies. Therefore, the marketing concept of the electronic resources should be reader oriented, such as respecting and understanding library user’s information needs. Libraries also need to utilize various media and techniques to market the electronic resources, so that more comprehensive services and experiences can be provided to readers. The purpose of this study is to investigate library user’s needs and promotion strategies of electronic resources in order to identify the most effective ways of marketing. This study focuses on the students of the four colleges (College of Business, College of Tourism, College of Information, and College of Humanities and Social Science in Kainan University as subjects in the survey questionnaire. It uses the Gap Analysis

  12. Sedimentological and Scanning Electron Miscroscopic Descriptions of Afowo Oil Sand Deposits, South Western Nigeria

    Directory of Open Access Journals (Sweden)

    Akinmosin A

    2017-12-01

    Full Text Available Sedimentological and scanning electron microscopic analyses of some shallow reservoir tar sand samples in parts of Southwestern Nigeria were carried out with the aim of characterizing the reservoir properties in relation to bitumen saturation and recovery efficiency. The production of impregnated tar from the sands requires the reservoir to be of good quality. A total of thirty samples were collected at different localities within the tar sand belt (ten out of these samples were selected for various reservoir quality analyses based on their textural homogeneity. The result of particle size distribution study showed that bulk of the sands is medium – coarse grained and moderately sorted. The grain morphologies are of low to high sphericity with shapes generally sub-angular to sub-rounded, implying that the sands have undergone a fairly long transportation history with depositional energy having a moderate to high velocity. The quartz content was made up of about 96% of the total mineralogical components; the sediments of the Afowo Formation can be described to be mineralogically and texturally stable. The result of the scanning electron microscopy (SEM analysis revealed that the oil sands contained minerals which had been precipitated and occurred as pore filling cement; these minerals include sheet kaolinite, block kaolinite, vermiform kaolinite, pyrite crystals and quartz. The SEM images also showed micro-pores ranging from 0.057µm to 0.446µm and fractures. The study showed that the clay minerals contained in the Afowo reservoir rocks were mainly kaolinite. Kaoline unlike some other clays (e.g Montimorillonite does not swell with water, hence it is not expected to have any negative effects on the reservoir quality, especially during enhanced oil recovery operations.

  13. Application of electronic learning tools for training of specialists in the field of information technologies for enterprises of mineral resources sector

    Directory of Open Access Journals (Sweden)

    Е. В. Катунцов

    2017-08-01

    Full Text Available The article shows the advantages of using modern electronic learning tools in the training of specialists for the mineral and raw materials complex and considers the basic principles of organizing training using these tools. The experience of using electronic learning tools using foreign teaching materials and involving foreign professors is described. A special attention is given to the electronic learning environment of the Cisco Networking Academy – Cisco NetAcad. The experience of teaching at the Networking Academy of the Saint-Petersburg Mining University is described. Details are given to modern virtual environments for laboratory work, such as Cisco Packet Tracer, GNS3 and Emulated Virtual Environment. The experience of using electronic learning technologies at the University of Economics of Bratislava is considered. It actively cooperates with a number of universities of other countries, such as the University of International Business (Almaty, the Eurasian National University named after LN Gumilyov (Astana and the Institute of Social and Humanitarian Knowledge (Kazan.

  14. An operational utility assessment [electronic resource]: measuring the effectiveness of the Joint Concept Technology Demonstration (JCTD), Joint Forces Protection Advance Security System (JFPASS)

    OpenAIRE

    McGovern, Mark; Mayor, Jeffrey D.; Symmes, Joseph

    2008-01-01

    MBA Professional Report Planning modern military operations requires an accurate intelligence assessment of potential threats, combined with a detailed assessment of the physical theater of operations. This information can then be combined with equipment and manpower resources to set up a logistically supportable operation that mitigates as much of the enemy threat as possible. Given such a daunting challenge, military planners often turn to intelligent software agents to support their...

  15. Positive Perceptions of Access to Online Library Resources Correlates with Quality and Quantity of Scholarly Publications among Finnish Academics. A Review of: Vakkari, Pertti. “Perceived Influence of the Use of Electronic Information Resources on Scholarly Work and Publication Productivity.” Journal of the American Society for Information Science and Technology 59.4 (Feb. 15, 2008: 602-12.

    Directory of Open Access Journals (Sweden)

    Scott Marsalis

    2008-12-01

    Full Text Available Objective – To investigate the relationship between academics’ use of library electronic resources and their opinions regarding how these resources have impacted their work, and to investigate the association between this perceived influence and publication productivity during the previous two years.Design – Two specific questions added to an annual online user-survey questionnaire; additional data mined from surveySetting – Twenty-two Finnish Universities served by FinELib, the Finnish Electronic Library.Subjects – Seven hundred and sixty seven academic staff and full-time doctoral students.Methods – A questionnaire was posted in April 2007 on FinELib’s homepage and advertised on each university library’s mainpage, and focused on respondents’ experience in the previous two years. Participants selected answers either from a list of category choices, or, when measuring perceptions, by rating agreement with statements along a four-point scale. Controlled variables measured were the respondents’ academic position, their discipline, membership in a research group, whether their literature use was discipline-specific or interdisciplinary, and their perception of the availability online of the relevant core literature. The independent variable measured was the scholars’ perception of the impact of the use of electronic library resources on their work. The dependent variable measured was the scholars’ self-reported publications in the two years preceding the survey.Main Results – Participants reported a positive impact on the efficiency of their work, most strongly in areas of ease of access, with lesser impacts in the range of materials available to them and the ease with which they can keep up-to-date in their field. To a lesser extent, the scholars perceived a positive impact on the quality of their work. Upon analysis, the study found that access to online library resources improved scholars’ work by the interconnected

  16. Power Electronics

    DEFF Research Database (Denmark)

    Iov, Florin; Ciobotaru, Mihai; Blaabjerg, Frede

    2008-01-01

    is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss the most...... emerging renewable energy sources, wind energy, which by means of power electronics are changing from being a minor energy source to be acting as an important power source in the energy system. Power electronics is the enabling technology and the presentation will cover the development in wind turbine...... technology from kW to MW, discuss which power electronic solutions are most feasible and used today....

  17. Merge of terminological resources

    DEFF Research Database (Denmark)

    Henriksen, Lina; Braasch, Anna

    2012-01-01

    In our globalized world, the amount of cross-national communication increases rapidly, which also calls for easy access to multi-lingual high quality terminological resources. Sharing of terminology resources is currently becoming common practice, and efficient strategies for integration...... – or merging – of terminology resources are strongly needed. This paper discusses prerequisites for successful merging with the focus on identification of candidate duplicates of a subject domain found in the resources to be merged, and it describes automatic merging strategies to be applied to such duplicates...... in electronic terminology resources. Further, some perspectives of manual, supplementary assessment methods supporting the automatic procedures are sketched. Our considerations are primarily based on experience gained in the IATE and EuroTermBank projects, as merging was a much discussed issue in both projects....

  18. Renewable energy resources

    DEFF Research Database (Denmark)

    Ellabban, Omar S.; Abu-Rub, Haitham A.; Blaabjerg, Frede

    2014-01-01

    Electric energy security is essential, yet the high cost and limited sources of fossil fuels, in addition to the need to reduce greenhouse gasses emission, have made renewable resources attractive in world energy-based economies. The potential for renewable energy resources is enormous because...... they can, in principle, exponentially exceed the world's energy demand; therefore, these types of resources will have a significant share in the future global energy portfolio, much of which is now concentrating on advancing their pool of renewable energy resources. Accordingly, this paper presents how...... renewable energy resources are currently being used, scientific developments to improve their use, their future prospects, and their deployment. Additionally, the paper represents the impact of power electronics and smart grid technologies that can enable the proportionate share of renewable energy...

  19. EFFECTIVE ELECTRONIC TUTORIAL

    Directory of Open Access Journals (Sweden)

    Andrei A. Fedoseev

    2014-01-01

    Full Text Available The article analyzes effective electronic tutorials creation and application based on the theory of pedagogy. Herewith the issues of necessary electronic tutorial functional, ways of the educational process organization with the use of information and communication technologies and the logistics of electronic educational resources are touched upon. 

  20. Sorption of cobalt in zeolites and natural clays of the clinoptilolite and kaolinite type; Sorcion de cobalto en zeolitas y arcillas naturales del tipo clinoptilolita y caolinita

    Energy Technology Data Exchange (ETDEWEB)

    Davila R, J.I.; Solache R, M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2006-07-01

    In this work the sorption of cobalt of aqueous solutions in two natural zeolites (clinoptilolite) and a clay (kaolinite) of origin in the center-north region of Mexico is evaluated. The effect of the pH and the time of contact in the process of sorption were evaluated. The cobalt retained in the aluminosilicates was determined by neutron activation analysis. The cobalt sorption in the materials in a range of pH from 4 to 7 does not present significant variations. The studies of reaction kinetics show a very fast sorption in the first 5 hours of contact, reaching the equilibrium in approximately 24 hours. The kinetics of sorption of the cobalt ions was represented better by the Ritchie reaction model modified of second order. The experimental data for the zeolites obtained at ambient temperature and varying the concentration were adjusted to the models of Freundlich, Langmuir and Freundlich-Langmuir isotherms and it was observed that the cobalt sorption it behaves according to the Freundlich isotherm model. (Author)

  1. Characterization of bentonite, fibrous and kaolinite clays with regard to their use in pelotherapy; Caracterizacion de bentonitas, arcillas fibrosas y arcillas caoliniferas para su empleo en peloterapia

    Energy Technology Data Exchange (ETDEWEB)

    Pozo Martin, E.; Martin Rubi, J. A.; Pozo Rodriguez, M.

    2011-07-01

    We have characterized the mineralogical and chemical contents of several Spanish special clays (bentonite, fibrous clays and kaolin). Mineralogical analyses revealed that the samples were composed mainly of phyllosilicates (78 %-99 %) with a notable presence of dioctahedral and trioctahedral smectites in the bentonite, kaolinite in the kaolin and sepiolite or palygorskite in the fibrous clays. Illite was the common subordinate mineral in the bentonite, kaolin and palygorskite. Quartz, calcite, dolomite and feldspars were found as associate minerals with the occasional presence of zeolites and amphiboles. The chemical analysis was consistent with the mineralogy. With regard to trace elements (V, Cr, Ni, Co, Cu, Zn, As, Mo, Ba, Sb, Pb, U), the whole samples of the magnesium bentonite and sepiolite were found to have the lowest trace-element contents (<257,28 ppm ), whilst the aluminium bentonite, kaolin and particularly the palygorskite had higher contents than the other clays, with some elements occasionally exceeding the contents of previously studied common clays. Nevertheless, all the trace elements were found in lower quantities than the recommended toxicity levels and those quantities currently used in pelotherapy in Spanish spas. (Author)

  2. Adsorption of Cs{sup +}, Ni{sup 2+} and lanthanides onto a kaolinite and Na-montmorillonite up to 150{sup 0}C: an experimental and modeling study; Adsorption de Cs{sup +}, Ni{sup 2+} et des lanthanides sur une kaolinite et une smectite jusqu'a 150{sup 0}C: etude experimentale et modelisation

    Energy Technology Data Exchange (ETDEWEB)

    Tertre, E

    2005-10-15

    The motivation for this study is to assess the temperature effect on the clay minerals sorption properties. Sorption and desorption of Cs{sup +}, Ni{sup 2+} et Ln{sup 3+} onto a montmorillonite and a kaolinite were performed by batch experiments between 25 and 150 C, and in different pH and ionic strengths conditions. Sorption enthalpies varying between 0 and 80 kJ/mol were then calculated. For europium, surface spectroscopic analyses confirmed that the mechanism involved is adsorption, including at 150 C. Moreover, this method allowed us to obtain qualitatively the different adsorption equilibrium occurring during the reaction. An acid/base study of the clay surfaces was performed in order to assess the temperature effect on the surface charge of these minerals. Then, a surface complexation model including edge sites and structural sites was proposed to interpret the acid/base data and the europium sorption data. (author)

  3. Real-world health outcomes in adults with moderate-to-severe psoriasis in the United States: a population study using electronic health records to examine patient-perceived treatment effectiveness, medication use, and healthcare resource utilization.

    Science.gov (United States)

    Armstrong, April W; Foster, Shonda A; Comer, Brian S; Lin, Chen-Yen; Malatestinic, William; Burge, Russel; Goldblum, Orin

    2018-06-28

    Little is known regarding real-world health outcomes data among US psoriasis patients, but electronic health records (EHR) that collect structured data at point-of-care may provide opportunities to investigate real-world health outcomes among psoriasis patients. Our objective was to investigate patient-perceived treatment effectiveness, patterns of medication use (duration, switching, and/or discontinuation), healthcare resource utilization, and medication costs using real-world data from psoriasis patients. Data for adults (≥18-years) with a dermatology provider-given diagnosis of psoriasis from 9/2014-9/2015 were obtained from dermatology practices using a widely used US dermatology-specific EHR containing over 500,000 psoriasis patients. Disease severity was captured by static physician's global assessment and body surface area. Patient-perceived treatment effectiveness was assessed by a pre-defined question. Treatment switching and duration were documented. Reasons for discontinuations were assessed using pre-defined selections. Healthcare resource utilization was defined by visit frequency and complexity. From 82,621 patients with psoriasis during the study period, patient-perceived treatment effectiveness was investigated in 2200 patients. The proportion of patients reporting "strongly agree" when asked if their treatment was effective was highest for biologics (73%) and those reporting treatment adherence (55%). In 16,000 patients who received oral systemics and 21,087 patients who received biologics, median treatment duration was longer for those who received biologics (160 vs. 113 days, respectively). Treatment switching was less frequent among patients on systemic monotherapies compared to those on combination therapies. The most common reason for discontinuing biologics was loss of efficacy; the most common reason for discontinuing orals was side effects. In 28,754 patients, higher disease severity was associated with increased healthcare resource

  4. Water Resources

    International Nuclear Information System (INIS)

    Abira, M.A.

    1997-01-01

    Water is essential for life and ecological sustenance; its availability is essential component of national welfare and productivity.The country's socio-economic activities are largely dependent on the natural endowment of water resources. Kenya's water resources comprises of surface waters (rivers, lakes and wetlands) and ground water. Surface water forms 86% of total water resources while the rest is ground water Geological, topographical and climatic factors influence the natural availability and distribution of water with the rainfall distribution having the major influence. Water resources in Kenya are continuously under threat of depletion and quality degradation owing to rising population, industrialization, changing land use and settlement activities as well as natural changes. However, the anticipated climate change is likely to exacerbate the situation resulting in increased conflict over water use rights in particular, and, natural resource utilisation in general. The impacts of climate change on the water resources would lead to other impacts on environmental and socio-economic systems

  5. Electronics and electronic systems

    CERN Document Server

    Olsen, George H

    1987-01-01

    Electronics and Electronic Systems explores the significant developments in the field of electronics and electronic devices. This book is organized into three parts encompassing 11 chapters that discuss the fundamental circuit theory and the principles of analog and digital electronics. This book deals first with the passive components of electronic systems, such as resistors, capacitors, and inductors. These topics are followed by a discussion on the analysis of electronic circuits, which involves three ways, namely, the actual circuit, graphical techniques, and rule of thumb. The remaining p

  6. Uranium resources

    International Nuclear Information System (INIS)

    Gangloff, A.

    1978-01-01

    It is first indicated how to evaluate the mining resources as a function of the cost of production and the degree of certainty in the knowledge of the deposit. A table is given of the world resources (at the beginning 1977) and resources and reserves are compared. There is a concordance between requirements and possible production until 1990. The case of France is examined: known reserves, present and future prospection, present production (In 1978 2200 T of U metal will be produced from 3 French processing plants), production coming from Cogema. A total production of 2000 T in 1980 and 10.000 in 1985 is expected [fr

  7. Seaweed resources

    Digital Repository Service at National Institute of Oceanography (India)

    Deshmukhe, G.V.; Dhargalkar, V.K.; Untawale, A.G.

    The chapter summarizes our present knowledge of the seaweed resources of the Indian Ocean region with regard to the phytogeographical distribution, composition, biomass, utilization, cultivation, conservation and management. The voluminous data...

  8. Arthritis - resources

    Science.gov (United States)

    Resources - arthritis ... The following organizations provide more information on arthritis : American Academy of Orthopaedic Surgeons -- orthoinfo.aaos.org/menus/arthritis.cfm Arthritis Foundation -- www.arthritis.org Centers for Disease Control and Prevention -- www. ...

  9. Mineral resources

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.

    (placers), biogenous (ooze, limestone) or chemogenous (phosphorites and polymetallic nodules) type. In recent years, hydrothermal deposits, cobalt crust and methane gas hydrates are considered as frontier resources. Their distribution depends upon proximity...

  10. Depression - resources

    Science.gov (United States)

    Resources - depression ... Depression is a medical condition. If you think you may be depressed, see a health care provider. ... following organizations are good sources of information on depression : American Psychological Association -- www.apa.org/topics/depression/ ...

  11. Hemophilia - resources

    Science.gov (United States)

    Resources - hemophilia ... The following organizations provide further information on hemophilia : Centers for Disease Control and Prevention -- www.cdc.gov/ncbddd/hemophilia/index.html National Heart, Lung, and Blood Institute -- www.nhlbi.nih.gov/ ...

  12. Diabetes - resources

    Science.gov (United States)

    Resources - diabetes ... The following sites provide further information on diabetes: American Diabetes Association -- www.diabetes.org Juvenile Diabetes Research Foundation International -- www.jdrf.org National Center for Chronic Disease Prevention and Health Promotion -- ...

  13. Forest Resources

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

    Forest biomass is an abundant biomass feedstock that complements the conventional forest use of wood for paper and wood materials. It may be utilized for bioenergy production, such as heat and electricity, as well as for biofuels and a variety of bioproducts, such as industrial chemicals, textiles, and other renewable materials. The resources within the 2016 Billion-Ton Report include primary forest resources, which are taken directly from timberland-only forests, removed from the land, and taken to the roadside.

  14. Teaching Resources

    Science.gov (United States)

    Physics?" Poster Pamphlets/Books/SPIN-UP Resources Making and Sustaining Changes in Undergraduate AAPT.org - American Association of Physics Teachers Skip to content Skip to navigation Skip to local navigation AAPT - American Association of Physics Teachers Go Sign In / Online Services Join

  15. Resource Mobilization

    International Development Research Centre (IDRC) Digital Library (Canada)

    constitute endorsement of the product and is given only for information. ..... point where they could significantly impact an organization's financial viability. This alternative ... putting in place internal systems and processes that enable the resource .... control over the incorporation of non-profit organizations. ..... Accounting.

  16. Resource Mobilization

    International Development Research Centre (IDRC) Digital Library (Canada)

    Annex 1: The Scoping Study on Donor Funding for. Development Research in ... publication of the Resource Mobilization: A Practical Guide for Research .... applied the concept or technique, which validates the practical application of ... some other staff member would write up a grant application addressed to one, two, or a ...

  17. Chemical dependence - resources

    Science.gov (United States)

    Substance use - resources, Drug abuse - resources; Resources - chemical dependence ... are a good resource for information on drug dependence: National Council on Alcoholism and Drug Dependence -- ncadd. ...

  18. Algae Resources

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

    Algae are highly efficient at producing biomass, and they can be found all over the planet. Many use sunlight and nutrients to create biomass, which contain key components—including lipids, proteins, and carbohydrates— that can be converted and upgraded to a variety of biofuels and products. A functional algal biofuels production system requires resources such as suitable land and climate, sustainable management of water resources, a supplemental carbon dioxide (CO2) supply, and other nutrients (e.g., nitrogen and phosphorus). Algae can be an attractive feedstock for many locations in the United States because their diversity allows for highpotential biomass yields in a variety of climates and environments. Depending on the strain, algae can grow by using fresh, saline, or brackish water from surface water sources, groundwater, or seawater. Additionally, they can grow in water from second-use sources such as treated industrial wastewater; municipal, agricultural, or aquaculture wastewater; or produced water generated from oil and gas drilling operations.

  19. Uranium resources

    International Nuclear Information System (INIS)

    1976-01-01

    This is a press release issued by the OECD on 9th March 1976. It is stated that the steep increases in demand for uranium foreseen in and beyond the 1980's, with doubling times of the order of six to seven years, will inevitably create formidable problems for the industry. Further substantial efforts will be needed in prospecting for new uranium reserves. Information is given in tabular or graphical form on the following: reasonably assured resources, country by country; uranium production capacities, country by country; world nuclear power growth; world annual uranium requirements; world annual separative requirements; world annual light water reactor fuel reprocessing requirements; distribution of reactor types (LWR, SGHWR, AGR, HWR, HJR, GG, FBR); and world fuel cycle capital requirements. The information is based on the latest report on Uranium Resources Production and Demand, jointly issued by the OECD's Nuclear Energy Agency (NEA) and the International Atomic Energy Agency. (U.K.)

  20. Modeling of the non isothermal and non isobaric transformations kinetics. Application to the kaolinite de-hydroxylation and to the tri-uranium octo-oxide reduction by hydrogen; Modelisation de la cinetique de transformations non isothermes et (ou) non isobares. Application a la deshydroxylation de la kaolinite et a la reduction de l'octooxyde de triuranium par l'hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    Perrin, St

    2002-12-15

    The aim of this work is to be able to describe transformations, occurring when solids and gases are in non isothermal and non isobaric conditions, with kinetic models. A methodology has been used. Two essential processes have to be taken into account: the germination and the growth. The germs are supposed to be formed (at constant temperature and pressure) in the grains surface with a constant velocity by surface unit, (gamma), called germination surface frequency (number of germs.m{sup -2}.s{sup -1}. The growth velocity is characterized by a growth surface reactivity, (phi) (in mol.m{sup -2}.s{sup -1}). With an appropriate transformation model, it is possible to obtain the variations of (gamma) and (phi) in terms of the temperature and pressure which are then used in the calculation of the velocity in non isothermal and non isobaric conditions. In order to validate the developed method, two reactions have been studied. For the first one, the kaolinite de-hydroxylation, an anisotropic germination-growth model, where the step limiting the growth is a diffusion step, has been developed in order to explain the experimental kinetic curves. Nevertheless the velocity curves calculated from this model do not allow to describe the reaction for some temperature variations. This result shows the difficulty to precisely determine the germination surface frequency what induces an important approximation on the kinetic curves. The second reaction is the tri-uranium octo-oxide reduction by hydrogen. It has been shown that this reaction occurs according to three successive transformations. A kinetic model has been developed for each of these reactions considering germination as instantaneous. At last, in comparing this model with the experimental velocity curves, a very good agreement has been verified as well as for a temperature variation than for a hydrogen partial pressure change during the reaction. (O.M.)

  1. Water resources

    International Nuclear Information System (INIS)

    2002-01-01

    The report entitled Climate Change Impacts and Adaptation : A Canadian Perspective, presents a summary of research regarding the impacts of climate change on key sectors over the past five years as it relates to Canada. This chapter on water resources describes how climate change will affect the supply of water in Canada. Water is one of Canada's greatest resources, which contributes about $7.5 to 23 billion per year to the Canadian economy. The decisions taken to adapt to climate change within the water resources sector will have profound implications in many other areas such as agriculture, human health, transportation and industry. The water related problems include water quality issues that relate to water shortages from droughts, or excesses from floods. The Intergovernmental Panel on Climate Change forecasts an increase in global average surface air temperatures of 1.4 to 5.8 degrees C by 2100. Such a change would impact the hydrological cycle, affecting runoff, evaporation patterns, and the amount of water stored in glaciers, lakes, wetlands and groundwater. The uncertainty as to the magnitude of these changes is due to the difficulty that climate models have in projecting future changes in regional precipitation patterns and extreme events. This chapter presents potential impacts of climate change on water resources in the Yukon, British Columbia, the Prairies, the Great Lakes basin, the Atlantic provinces, and the Arctic and Subarctic. The associated concerns for each region were highlighted. Adaptation research has focused on the impacts of supply and demand, and on options to adapt to these impacts. 60 refs., 2 tabs., 1 fig

  2. A review of the surface features and properties, surfactant adsorption and floatability of four key minerals of diasporic bauxite resources.

    Science.gov (United States)

    Zhang, Ningning; Nguyen, Anh V; Zhou, Changchun

    2018-04-01

    Diasporic bauxite represents one of the major aluminum resources. Its upgrading for further processing involves a separation of diaspore (the valuable mineral) from aluminosilicates (the gangue minerals) such as kaolinite, illite, and pyrophyllite. Flotation is one of the most effective ways to realize the upgrading. Since flotation is a physicochemical process based on the difference in the surface hydrophobicity of different components, determining the adsorption characteristics of various flotation surfactants on the mineral surfaces is critical. The surfactant adsorption properties of the minerals, in turn, are controlled by the surface chemistry of the minerals, while the latter is related to the mineral crystal structures. In this paper, we first discuss the crystal structures of the four key minerals of diaspore, kaolinite, illite, and pyrophyllite as well as the broken bonds on their exposed surfaces after grinding. Next, we summarize the surface chemistry properties such as surface wettability and surface electrical properties of the four minerals, and the differences in these properties are explained from the perspective of mineral crystal structures. Then we review the adsorption mechanism and adsorption characteristics of surfactants such as collectors (cationic, anionic, and mixed surfactants), depressants (inorganic and organic), dispersants, and flocculants on these mineral surfaces. The separation of diaspore and aluminosilicates by direct flotation and reverse flotation are reviewed, and the collecting properties of different types of collectors are compared. Furthermore, the abnormal behavior of the cationic flotation of kaolinite is also explained in this section. This review provides a strong theoretical support for the optimization of the upgrading of diaspore bauxite ore by flotation and the early industrialization of the reverse flotation process. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Resource Abundance and Resource Dependence in China

    NARCIS (Netherlands)

    Ji, K.; Magnus, J.R.; Wang, W.

    2010-01-01

    This paper reconsiders the ‘curse of resources’ hypothesis for the case of China, and distinguishes between resource abundance, resource rents, and resource dependence. Resource abundance and resource rents are shown to be approximately equivalent, and their association with resource dependence

  4. Internet and Electronic Information Management

    Science.gov (United States)

    2004-12-01

    centers to form consortia and share electronic information sources. Although traditional resource sharing arrangements encouraged competition rather...outside world, through public relations and through marketing information products or services, to its own competitive advantage (Davenport 1997: 193-217... electronic information sources are a challenge for electronic information managers. Libraries and information centers are no longer “the only game in town

  5. Automotive electronics design fundamentals

    CERN Document Server

    Zaman, Najamuz

    2015-01-01

    This book explains the topology behind automotive electronics architectures and examines how they can be profoundly augmented with embedded controllers. These controllers serve as the core building blocks of today’s vehicle electronics. Rather than simply teaching electrical basics, this unique resource focuses on the fundamental concepts of vehicle electronics architecture, and details the wide variety of Electronic Control Modules (ECMs) that enable the increasingly sophisticated "bells & whistles" of modern designs.  A must-have for automotive design engineers, technicians working in automotive electronics repair centers and students taking automotive electronics courses, this guide bridges the gap between academic instruction and industry practice with clear, concise advice on how to design and optimize automotive electronics with embedded controllers.

  6. Uranium resource processing. Secondary resources

    International Nuclear Information System (INIS)

    Gupta, C.K.; Singh, H.

    2003-01-01

    This book concentrates on the processing of secondary sources for recovering uranium, a field which has gained in importance in recent years as it is environmental-friendly and economically in tune with the philosophy of sustainable development. Special mention is made of rock phosphate, copper and gold tailings, uranium scrap materials (both natural and enriched) and sea water. This volume includes related area of ore mineralogy, resource classification, processing principles involved in solubilization followed by separation and safety aspects

  7. Energy resources

    CERN Document Server

    Simon, Andrew L

    1975-01-01

    Energy Resources mainly focuses on energy, including its definition, historical perspective, sources, utilization, and conservation. This text first explains what energy is and what its uses are. This book then explains coal, oil, and natural gas, which are some of the common energy sources used by various industries. Other energy sources such as wind, solar, geothermal, water, and nuclear energy sources are also tackled. This text also looks into fusion energy and techniques of energy conversion. This book concludes by explaining the energy allocation and utilization crisis. This publ

  8. Transformações mineralógicas e cristaloquímicas decorrentes dos ensaios termais em argilas cauliníticas ferruginosas Mineralogical and crystalochemical transformations originated from thermal essays on ferruginous kaolinitic clays

    Directory of Open Access Journals (Sweden)

    M. M. Ferreira

    2012-03-01

    Full Text Available Transformações mineralógicas e cristaloquímicas foram investigadas em amostras de argilas cauliníticas ferruginosas aquecidas a temperaturas de 800, 1000 e 1200 °C. As análises de difração de raios X e térmica diferencial e gravimétrica mostraram ser a caulinita o argilomineral predominante nas amostras naturais. Os resultados da espectroscopia Mössbauer mostraram que o alto conteúdo em Fe (22,5% em peso, determinado por fluorescência de raios X, é relacionado à presença de goethita (18% em peso e hematita (16% em peso. Entretanto um resíduo deste elemento (Fe3+ e Fe2+ foi constatado após a extração do ferro usando solução de ditionito-citrato-bicarbonato, e possivelmente se deve à presença de ferro na estrutura da caulinita. O processo de sinterização mostra uma desestruturação da caulinita, assim como a transformação da goethita em hematita, cujo tamanho dos cristais cresce com o incremento da temperatura. O tamanho do cristal de hematita a 1200 °C é 5 vezes maior do que na amostra natural. A mulita formada a 1000 °C é constituída da solução sólida de Fe2O3, com Al2O3, o que resulta em produto resistente e de maior estabilidade térmica.Mineralogical and crystallochemical transformations of representative ferruginous kaolinitic clay samples were investigated in specimens burned at 800, 1000 and 1200 °C. X-ray diffraction and differential thermal and thermogravimetric analyses showed that kaolinite was the predominant mineral in the raw samples. The Mössbauer spectroscopy results showed that the high iron content (22.5 wt.%, as determined by X-ray fluorescence, is related to the presence of goethite (18 wt.% and hematite (16 wt.%. However, after Fe was extracted using a dithionite-citrate system buffered with sodium bicarbonate, a residue of this element (Fe3+ and Fe2+ was found in the structure of the kaolinite. The sintering process showed the destruction of kaolinite, as well as the transformation of

  9. Electronic technology

    International Nuclear Information System (INIS)

    Kim, Jin Su

    2010-07-01

    This book is composed of five chapters, which introduces electronic technology about understanding of electronic, electronic component, radio, electronic application, communication technology, semiconductor on its basic, free electron and hole, intrinsic semiconductor and semiconductor element, Diode such as PN junction diode, characteristic of junction diode, rectifier circuit and smoothing circuit, transistor on structure of transistor, characteristic of transistor and common emitter circuit, electronic application about electronic equipment, communication technology and education, robot technology and high electronic technology.

  10. Mineral resources

    International Nuclear Information System (INIS)

    1991-09-01

    This paper reports that to prevent the concentration of control over federal oil and gas resources in a few companies or individuals, Congress has limited the number of acres of oil and gas leases that one party may control in a single state. An exception to this limitation involves lease acreage within the boundaries of development contracts. These contracts permit oil and gas lease operators and pipeline companies to contract with enough lessees to economically justify large-scale drilling operations for the production and transportation of oil and gas, subject to approval by the Secretary of the Interior, who must find that such contracts are in the public interest. Since 1986 Interior has entered into or approved 10 contracts with 12 lease operators for exploration of largely unleased federal lands-ranging from about 180,000 to 3.5 million acres in four western states-and has designated them as developmental contracts. GAO believes that the 10 contracts do not satisfy the legal requirements for development contracts because they are for oil and gas exploration on largely unleased federal lands, rather than for developing existing leases. By designating the 10 contracts as development contracts, Interior has enabled nine of the 12 contract parties to accumulate lease acreage that vastly exceeds the statutory acreage limitation. All nine of the contract parties were major or large independent oil companies. As a result, other parties who wish to participate in developing federal oil and gas resources within the four states may be adversely affected because the parties to Interior's contracts have been able to compete for and obtain lease acreage beyond the statutory acreage limitation. Although Interior believes that the Secretary has the discretion under law to use development contracts in the current manner, in April 1989 it ceased issuing these contracts pending completion of GAO's review

  11. The Electron

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, George

    1972-01-01

    Electrons are elementary particles of atoms that revolve around and outside the nucleus and have a negative charge. This booklet discusses how electrons relate to electricity, some applications of electrons, electrons as waves, electrons in atoms and solids, the electron microscope, among other things.

  12. Hard electronics; Hard electronics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Hard material technologies were surveyed to establish the hard electronic technology which offers superior characteristics under hard operational or environmental conditions as compared with conventional Si devices. The following technologies were separately surveyed: (1) The device and integration technologies of wide gap hard semiconductors such as SiC, diamond and nitride, (2) The technology of hard semiconductor devices for vacuum micro- electronics technology, and (3) The technology of hard new material devices for oxides. The formation technology of oxide thin films made remarkable progress after discovery of oxide superconductor materials, resulting in development of an atomic layer growth method and mist deposition method. This leading research is expected to solve such issues difficult to be easily realized by current Si technology as high-power, high-frequency and low-loss devices in power electronics, high temperature-proof and radiation-proof devices in ultimate electronics, and high-speed and dense- integrated devices in information electronics. 432 refs., 136 figs., 15 tabs.

  13. Interestratificado caulinita-esmectita em um argissolo desenvolvido a partir de rocha sedimentar do Sul do Brasil Interlayered kaolinite-smectite minerals in an acrisol developed from sandstone parent material in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Edson Campanhola Bortoluzzi

    2007-12-01

    , indicando que ela é proveniente de herança do material de origem. A mineralogia deste solo indica estádio intermediário entre argilominerais de estrutura do tipo 2:1 e 1:1 no processo de intemperismo.Kaolinite is commonly found in fine fractions of tropical and subtropical Brazilian soils. Kaolinite can be verified by an X-ray diffractogram, made of a series of 00l peaks, at the distance of 0.715 nm. However, in some soils, major peaks can be found at about d = 0.720 nm, indicating halloysite or kaolinite-smectite (K-S interstratified minerals. The objectives of this study were to verify this hypothesis and subsequently discuss soil genesis. Parent material and soil samples from the horizons A1, A2, E and Bt were collected in a Red Yellow Acrisol, covered by native vegetation, on the Campus of the Universidade Federal de Santa Maria, RS, Brazil. The clay fraction was separated by sedimentation, Ca2+ saturated and X-ray diffracted after the following treatments: control, air drying, (N; ethylene-glycol saturation (EG; heating to 300 and 550 °C; and, after formamide saturation. The raw X-ray diffractograms (XRD were modeled between 11 and 15 degrees 2 theta (using DecompRX. Two peaks were found in the XRD around this region. The first peak was sharp and intense at d = 0.717 nm, corresponding to kaolinite; the second, broader and less intense, was observed at d = 0.720 nm. The peak at d = 0.720 nm was sensitive to EG treatment; it varied from d = 0.720 nm to d = 0.730 nm and returned to about d = 0.720 nm after heating to 300 °C. This behaviour is typical of expansive layers. The presence of interstratified K-S minerals was inferred since halloysite clay was not identified by the formamide test. The XRD were analyzed and indicated interstratified K-S mineral at a proportion of 0.8_0.9 kaolinite layers and 0.1-0.2 smectite layers. Furthermore, the K-S covered about 90 % and kaolinite alone 10 % of the modelled peak, at d = 0.720 nm. K-S was also found in the bedrock

  14. Social Studies Online Resources. Media Corner.

    Science.gov (United States)

    Wilson, Jeri, Ed.

    1995-01-01

    Maintains that three types of social studies activities are found on the information highway: (1) electronic mail; (2) information; and (3) conferencing. Describes examples of each. Discusses commercial services and resource materials and provides references to online services. (CFR)

  15. The Biomedical Resource Ontology (BRO) to enable resource discovery in clinical and translational research.

    Science.gov (United States)

    Tenenbaum, Jessica D; Whetzel, Patricia L; Anderson, Kent; Borromeo, Charles D; Dinov, Ivo D; Gabriel, Davera; Kirschner, Beth; Mirel, Barbara; Morris, Tim; Noy, Natasha; Nyulas, Csongor; Rubenson, David; Saxman, Paul R; Singh, Harpreet; Whelan, Nancy; Wright, Zach; Athey, Brian D; Becich, Michael J; Ginsburg, Geoffrey S; Musen, Mark A; Smith, Kevin A; Tarantal, Alice F; Rubin, Daniel L; Lyster, Peter

    2011-02-01

    The biomedical research community relies on a diverse set of resources, both within their own institutions and at other research centers. In addition, an increasing number of shared electronic resources have been developed. Without effective means to locate and query these resources, it is challenging, if not impossible, for investigators to be aware of the myriad resources available, or to effectively perform resource discovery when the need arises. In this paper, we describe the development and use of the Biomedical Resource Ontology (BRO) to enable semantic annotation and discovery of biomedical resources. We also describe the Resource Discovery System (RDS) which is a federated, inter-institutional pilot project that uses the BRO to facilitate resource discovery on the Internet. Through the RDS framework and its associated Biositemaps infrastructure, the BRO facilitates semantic search and discovery of biomedical resources, breaking down barriers and streamlining scientific research that will improve human health. Copyright © 2010 Elsevier Inc. All rights reserved.

  16. Electron radiography

    Science.gov (United States)

    Merrill, Frank E.; Morris, Christopher

    2005-05-17

    A system capable of performing radiography using a beam of electrons. Diffuser means receive a beam of electrons and diffuse the electrons before they enter first matching quadrupoles where the diffused electrons are focused prior to the diffused electrons entering an object. First imaging quadrupoles receive the focused diffused electrons after the focused diffused electrons have been scattered by the object for focusing the scattered electrons. Collimator means receive the scattered electrons and remove scattered electrons that have scattered to large angles. Second imaging quadrupoles receive the collimated scattered electrons and refocus the collimated scattered electrons and map the focused collimated scattered electrons to transverse locations on an image plane representative of the electrons' positions in the object.

  17. Information resources

    Science.gov (United States)

    Friend, Milton; Franson, J. Christian; Friend, Milton; Gibbs, Samantha E.J.; Wild, Margaret A.

    2015-10-19

    During recent decades, natural resources agency personnel and others involved with the management and stewardship of wildlife have experienced an increasing need to access information and obtain technical assistance for addressing a diverse array of wildlife disease issues. This Chapter provides a broad overview of selected sources for obtaining supplemental information and technical assistance for addressing wildlife disease issues in North America. Specifically, examples of existing major wildlife disease programs focusing on free-ranging wildlife populations are highlighted; training opportunities for enhancing within-agency wildlife disease response are identified; a selected reading list of wildlife disease references is provided; and selected Web sites providing timely information on wildlife disease are highlighted. No attempt is made to detail all the North American programs and capabilities that address disease in free-ranging wildlife populations. Instead, this Chapter is focused on enhancing awareness of the types of capabilities that exist as potential sources for assistance and collaboration between wildlife conservation agency personnel and others in addressing wildlife disease issues.

  18. GENDER ANALYSIS OF ELECTRONIC INFORMATION

    African Journals Online (AJOL)

    use of internet Search engines such as google, yahoo and other free internet resources was found ... empirical studies are undertaken to examine the influence of gender ... H3: Perceived ease of use is positively related to the use of electronic.

  19. Oscillator clustering in a resource distribution chain

    DEFF Research Database (Denmark)

    Postnov, D.; Sosnovtseva, Olga; Mosekilde, Erik

    2005-01-01

    separate the inherent dynamics of the individual oscillator from the properties of the coupling network. Illustrated by examples from microbiological population dynamics, renal physiology, and electronic oscillator theory, we show how competition for primary resources in a resource distribution chain leads...

  20. Shaping the Electronic Library--The UW-Madison Approach.

    Science.gov (United States)

    Dean, Charles W., Ed.; Frazier, Ken; Pope, Nolan F.; Gorman, Peter C.; Dentinger, Sue; Boston, Jeanne; Phillips, Hugh; Daggett, Steven C.; Lundquist, Mitch; McClung, Mark; Riley, Curran; Allan, Craig; Waugh, David

    1998-01-01

    This special theme section describes the University of Wisconsin-Madison's experience building its Electronic Library. Highlights include integrating resources and services; the administrative framework; the public electronic library, including electronic publishing capability and access to World Wide Web-based and other electronic resources;…

  1. Electrons, Electronic Publishing, and Electronic Display.

    Science.gov (United States)

    Brownrigg, Edwin B.; Lynch, Clifford A.

    1985-01-01

    Provides a perspective on electronic publishing by distinguishing between "Newtonian" publishing and "quantum-mechanical" publishing. Highlights include media and publishing, works delivered through electronic media, electronic publishing and the printed word, management of intellectual property, and recent copyright-law issues…

  2. 研究/電子資源使用統計標準與規範之探討/陳雪華;許嘉珍;朱雅琦 | Study of the Electronic Resources Usage Statistics Standards and Guidelines/ Hsueh-Hua Chen;Chia-Chen Hsu;Ya-Chi Chu

    Directory of Open Access Journals (Sweden)

    陳雪華、許嘉珍、朱雅琦

    2007-04-01

    Full Text Available

    近年來,由於資訊科技的進步,圖書館中的電子資源數量快速增加,所佔預算金額比例也大幅增長。圖書館希望能夠透過評鑑電子資源的使用,以便能夠在電 子資源館藏發展等方面做出正確的決策。由於體認到電子資源使用統計之重要性,圖書館界與相關組織紛紛發展或修訂圖書館統計標準,增列電子資源使用統計的項 目以充分反映圖書館電子資源使用之狀況。本文主要採用文獻分析法以及內容分析法,收集探討並比較近軍來國內外電子資源使用統計之相關規範及標準,包含 ISO 2789、 ICOLC Guidelines、州ANSI/NISO Z39.7、CNS13151、ARL E-Metrlcs、E-Measures Project、以及Project COUNTER等。

    Recently, due to the advances of information technology, electronic resources are gradually replacing print resources as the largest consumer of library acquisition budgets. Logically, libraries want to evaluate the usage of electronic resources and incorporate the results into their decision making regarding electronic resource acquisition. Over these years, there is a general awareness among libraries to develop statistics standards and guidelines for library electronic resources usage. In this paper, literature review and content analysis methods are used to compare several library statistics standards, including: ISO 2789 、ICOLC Guidelines、ANSI/NISO Z39.7、CNS13151、ARL E-Metrics、E-Measures Project、and Project COUNTER etc.

    頁次:89-102

  3. Development of Surface Complexation Models of Cr(VI) Adsorption on Soils, Sediments and Model Mixtures of Kaolinite, Montmorillonite, γ-Alumina, Hydrous Manganese and Ferric Oxides and Goethite

    Energy Technology Data Exchange (ETDEWEB)

    Koretsky, Carla [Western Michigan University

    2013-11-29

    Hexavalent chromium is a highly toxic contaminant that has been introduced into aquifers and shallow sediments and soils via many anthropogenic activities. Hexavalent chromium contamination is a problem or potential problem in the shallow subsurface at several DOE sites, including Hanford, Idaho National Laboratory, Los Alamos National Laboratory and the Oak Ridge Reservation (DOE, 2008). To accurately quantify the fate and transport of hexavalent chromium at DOE and other contaminated sites, robust geochemical models, capable of correctly predicting changes in chromium chemical form resulting from chemical reactions occurring in subsurface environments are needed. One important chemical reaction that may greatly impact the bioavailability and mobility of hexavalent chromium in the subsurface is chemical binding to the surfaces of particulates, termed adsorption or surface complexation. Quantitative thermodynamic surface complexation models have been derived that can correctly calculate hexavalent chromium adsorption on well-characterized materials over ranges in subsurface conditions, such pH and salinity. However, models have not yet been developed for hexavalent chromium adsorption on many important constituents of natural soils and sediments, such as clay minerals. Furthermore, most of the existing thermodynamic models have been developed for relatively simple, single solid systems and have rarely been tested for the complex mixtures of solids present in real sediments and soils. In this study, the adsorption of hexavalent chromium was measured as a function of pH (3-10), salinity (0.001 to 0.1 M NaNO3), and partial pressure of carbon dioxide(0-5%) on a suite of naturally-occurring solids including goethite (FeOOH), hydrous manganese oxide (MnOOH), hydrous ferric oxide (Fe(OH)3), γ-alumina (Al2O3), kaolinite (Al2Si2O5(OH)4), and montmorillonite (Na3(Al, Mg)2Si4O10(OH)2-nH2O). The results show that all of these materials can bind substantial quantities of

  4. Electron detector

    International Nuclear Information System (INIS)

    Hashimoto, H.; Mogami, A.

    1975-01-01

    A device for measuring electron densities at a given energy level in an electron beam or the like having strong background noise, for example, in the detection of Auger electric energy spectrums is described. An electron analyzer passes electrons at the given energy level and at the same time electrons of at least one adjacent energy level. Detecting means associated therewith produce signals indicative of the densities of the electrons at each energy level and combine these signals to produce a signal indicative of the density of the electrons of the given energy level absent background noise

  5. World resources: engineering solutions

    Energy Technology Data Exchange (ETDEWEB)

    1976-01-01

    The proceedings include 10 papers that contribute to population environment; fossil fuel resources and energy conservation; nuclear and solar power; production of ores and manufacture and use of metallic resources; resources of manufactured and natural nonmetallic materials; water as a reusable resource; and timber as a replaceable resource.

  6. Electron/electron acoustic instability

    International Nuclear Information System (INIS)

    Gary, S.P.

    1987-01-01

    The electron acoustic wave becomes a normal mode of an unmagnetized collisionless plasma in the presence of two electron components with similar densities, but strongly disparate temperatures. The characteristic frequency of this mode is the plasma frequency of the cooler electron component. If these two electron components have a relative drift speed several times the thermal speed of the cooler component, the electron/electron acoustic instability may arise. This paper describes the parametric dependences of the threshold drift speed and maximum growth rate of this instability, and compares these with the same properties of the electron/ion acoustic instability. Under the condition of zero current, the electron/ion acoustic instability typically has the lower threshold drift speed, so that observation of the electron/electron acoustic instability is a strong indication of the presence of an electrical current in the plasma

  7. Innovations in electronic services

    Directory of Open Access Journals (Sweden)

    Dagmara Wach

    2011-12-01

    Full Text Available Summarry Existence in electronic business has become increasingly difficult. High competition and considerable financial resources needed to enter electronic market are the problems of most micro and small sized enterprises, starting or developing their business. Nevertheless, there is a market niche for them, which can ensure success and grant partial financing of the business. This niche are small web projects, providing the customer with personalized service, hitting his tastes and meeting immediate needs. A projects that large websites are unable to perform. Financial sourcing of those projects comes from EU subsidies, in the framework of the Działanie 8.1. PO IG, 2007-2013.

  8. Electronic emission and electron guns

    International Nuclear Information System (INIS)

    Roy, Amitava

    2010-01-01

    This paper reviews the process of electron emission from metal surface. Although electrons move freely in conductors like metals, they normally do not leave the metal without some manipulation. In fact, heating and bombardment are the two primary ways in which electrons are emitted through the use of a heating element behind the cathode (termed thermionic emission) or as a result of bombardment with a beam of electrons, ions, or metastable atoms (termed secondary emission). Another important emission mechanism called Explosive Electron Emission (EEE) is also often used in various High Voltage Pulse Power Systems to generate very high current (few hundreds of kA) pulsed electron beams. The electron gun is the device in that it shoots off a continuous (or pulsed) stream of electrons. A brief idea about the evolution of the electron gun components and their basis of functioning are also discussed. (author)

  9. Sticker electronics

    KAUST Repository

    Hussain, Muhammad Mustafa; Torres Sevilla, Galo Andres; Diaz Cordero, Marlon Steven

    2017-01-01

    Electronic stickers may be manufactured on flexible substrates (110, 120, 130) as layers and packaged together. The package may then have an adhesive applied to one side to provide capability for sticking the electronic devices to surfaces

  10. ELECTRONIC SIGNATURES

    African Journals Online (AJOL)

    10332324

    "[to] promote the understanding and, acceptance of and growth in the number of electronic transactions .... Chapter III of the ECT Act is based on the UNCITRAL Model Law on Electronic. Commerce ... Communications Technology Law 146. 22.

  11. Electronic components

    CERN Document Server

    Colwell, Morris A

    1976-01-01

    Electronic Components provides a basic grounding in the practical aspects of using and selecting electronics components. The book describes the basic requirements needed to start practical work on electronic equipment, resistors and potentiometers, capacitance, and inductors and transformers. The text discusses semiconductor devices such as diodes, thyristors and triacs, transistors and heat sinks, logic and linear integrated circuits (I.C.s) and electromechanical devices. Common abbreviations applied to components are provided. Constructors and electronics engineers will find the book useful

  12. Understand electronics

    CERN Document Server

    Bishop, Owen

    2013-01-01

    Understand Electronics provides a readable introduction to the exciting world of electronics for the student or enthusiast with little previous knowledge. The subject is treated with the minimum of mathematics and the book is extensively illustrated.This is an essential guide for the newcomer to electronics, and replaces the author's best-selling Beginner's Guide to Electronics.The step-by-step approach makes this book ideal for introductory courses such as the Intermediate GNVQ.

  13. Electronic Commerce

    OpenAIRE

    Slavko Đerić

    2016-01-01

    Electronic commerce can be defined in different ways. Any definition helps to understand and explain that concept as better as possible.. Electronic commerce is a set of procedures and technologies that automate the tasks of financial transactions using electronic means. Also, according to some authors, electronic commerce is defined as a new concept, which is being developed and which includes process of buying and selling or exchanging products, services or information via computer networks...

  14. Electronic Publishing.

    Science.gov (United States)

    Lancaster, F. W.

    1989-01-01

    Describes various stages involved in the applications of electronic media to the publishing industry. Highlights include computer typesetting, or photocomposition; machine-readable databases; the distribution of publications in electronic form; computer conferencing and electronic mail; collaborative authorship; hypertext; hypermedia publications;…

  15. Building the electronic industry's roadmaps

    Science.gov (United States)

    Boulton, William R.

    1995-02-01

    JTEC panelists found a strong consistency among the electronics firms they visited: all the firms had clear visions or roadmaps for their research and development activities and had committed resources to ensure that they achieve targeted results. The overarching vision driving Japan's electronics industry is that of achieving market success through developing appealing, high-quality, low-cost consumer goods - ahead of the competition. Specifics of the vision include improving performance, quality, and portability of consumer electronics products. Such visions help Japanese companies define in detail the roadmaps they will follow to develop new and improved electronic packaging technologies.

  16. Electronic Recruitment at CERN

    CERN Multimedia

    2004-01-01

    The Human Resources Department switches to electronic recruitment. From now on whenever you are involved in a recruitment action you will receive an e-mail giving you access to a Web folder. Inside you will find a shortlist of applications drawn up by the Human Resources Department. This will allow you to consult the folder, at the same time as everyone else involved in the recruitment process, for the vacancy you are interested in. This new electronic recruitment system, known as e-RT, will be introduced in a presentation given at 10 a.m. on 11 February in the Main Auditorium. Implemented by AIS (Administrative Information Services) and the Human Resources Department, e-RT will cover vacancies open in all of CERN's recruitment programmes. The electronic application system was initially made available to technical students in July 2003. By December it was extended to summer students, fellows, associates and Local Staff. Geraldine Ballet from the Recruitment Service prefers e-RT to mountains of paper! The Hu...

  17. Sticker electronics

    KAUST Repository

    Hussain, Muhammad Mustafa

    2017-09-08

    Electronic stickers may be manufactured on flexible substrates (110, 120, 130) as layers and packaged together. The package may then have an adhesive applied to one side to provide capability for sticking the electronic devices to surfaces. The stickers can be wrappable, placed on surfaces, glued on walls or mirrors or wood or stone, and have electronics (112, 122, 132) which may or may not be ultrathin. Packaging for the electronic sticker can use polymer on cellulose manufacturing and/or three dimensional (3-D) printing. The electronic stickers may provide lighting capability, sensing capability, and/or recharging capabilities.

  18. Basic electronics

    CERN Document Server

    Holbrook, Harold D

    1971-01-01

    Basic Electronics is an elementary text designed for basic instruction in electricity and electronics. It gives emphasis on electronic emission and the vacuum tube and shows transistor circuits in parallel with electron tube circuits. This book also demonstrates how the transistor merely replaces the tube, with proper change of circuit constants as required. Many problems are presented at the end of each chapter. This book is comprised of 17 chapters and opens with an overview of electron theory, followed by a discussion on resistance, inductance, and capacitance, along with their effects on t

  19. Network resource management

    NARCIS (Netherlands)

    2009-01-01

    The invention provides real time dynamic resource management to improve end-to-end QoS by mobile devices regularly updating a resource availability server (RAS) with resource update information. Examples of resource update information are device battery status, available memory, session bandwidth,

  20. The Global Resource Nexus

    NARCIS (Netherlands)

    Ridder, M. de; Duijne, F. van; Jong, S. de; Jones, J.; Luit, E. van; Bekkers, F.F.; Auping, W.

    2014-01-01

    Supply and demand of resources are connected in a complex way. This interconnectivity has been framed as the global resource nexus and can conceivebly include all types of resources. This study focus on the nexus of five essential natural resources: land, food, energy, water and minerals. Together

  1. Knowledge and Natural Resources

    DEFF Research Database (Denmark)

    Bertelsen, Rasmus Gjedssø; Justinussen, Jens Christian Svabo

    2016-01-01

    Arctic economies are generally natural resource based economies, whether they are indigenous economies largely dependent on living on the land or industrialized economies depending on marine resources, mineral resources or fossil or renewable energy resources. However, the central role of knowledge...

  2. Electronic Commerce and Electronic Business

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    This special issue is motivated by the recent upsurge of research activity in the areas of electronic commerce and electronic business both in India and all over the world. The current ... Monte Carlo methods for pricing financial options are then.

  3. Electronic Government and Electronic Participation

    NARCIS (Netherlands)

    Tambouris, E; Scholl, H.J.; Janssen, M.F.W.H.A.; Wimmer, M.A.; Tarabanis, K; Gascó, M; Klievink, A.J.; Lindgren, I; Milano, M; Panagiotopoulos, P; Pardo, T.A.; Parycek, P; Sæbø, Ø

    2016-01-01

    Electronic government and electronic participation continue to transform the public sector and society worldwide and are constantly being transformed themselves by emerging information and communication technologies.This book presents papers from the 14th International Federation for Information

  4. Electronic Government and Electronic Participation

    NARCIS (Netherlands)

    Tambouris, E.; Scholl, H.J.; Janssen, M.F.W.H.A.; Wimmer, M.A.; Tarabanis, K.; Gascó, M.; Klievink, A.J.; Lindgren, I.; Milano, M.; Panagiotopoulos, P.; Pardo, T.A.; Parycek, P.; Sæbø, O.

    2015-01-01

    Electronic government and electronic participation continue to transform the public sector and society worldwide and are constantly being transformed themselves by emerging information and communication technologies. This book presents papers from the 14th International Federation for Information

  5. Electron Tree

    DEFF Research Database (Denmark)

    Appelt, Ane L; Rønde, Heidi S

    2013-01-01

    The photo shows a close-up of a Lichtenberg figure – popularly called an “electron tree” – produced in a cylinder of polymethyl methacrylate (PMMA). Electron trees are created by irradiating a suitable insulating material, in this case PMMA, with an intense high energy electron beam. Upon discharge......, during dielectric breakdown in the material, the electrons generate branching chains of fractures on leaving the PMMA, producing the tree pattern seen. To be able to create electron trees with a clinical linear accelerator, one needs to access the primary electron beam used for photon treatments. We...... appropriated a linac that was being decommissioned in our department and dismantled the head to circumvent the target and ion chambers. This is one of 24 electron trees produced before we had to stop the fun and allow the rest of the accelerator to be disassembled....

  6. `Twisted' electrons

    Science.gov (United States)

    Larocque, Hugo; Kaminer, Ido; Grillo, Vincenzo; Leuchs, Gerd; Padgett, Miles J.; Boyd, Robert W.; Segev, Mordechai; Karimi, Ebrahim

    2018-04-01

    Electrons have played a significant role in the development of many fields of physics during the last century. The interest surrounding them mostly involved their wave-like features prescribed by the quantum theory. In particular, these features correctly predict the behaviour of electrons in various physical systems including atoms, molecules, solid-state materials, and even in free space. Ten years ago, new breakthroughs were made, arising from the new ability to bestow orbital angular momentum (OAM) to the wave function of electrons. This quantity, in conjunction with the electron's charge, results in an additional magnetic property. Owing to these features, OAM-carrying, or twisted, electrons can effectively interact with magnetic fields in unprecedented ways and have motivated materials scientists to find new methods for generating twisted electrons and measuring their OAM content. Here, we provide an overview of such techniques along with an introduction to the exciting dynamics of twisted electrons.

  7. Australian uranium resources

    International Nuclear Information System (INIS)

    Battey, G.C.; Miezitis, Y.; McKay, A.D.

    1987-01-01

    Australia's uranium resources amount to 29% of the WOCA countries (world outside centrally-planned-economies areas) low-cost Reasonably Assured Resources and 28% of the WOCA countries low-cost Estimated Additional Resources. As at 1 January 1986, the Bureau of Mineral Resources estimated Australia's uranium resources as: (1) Cost range to US$80/kg U -Reasonably Assured Resources, 465 000 t U; Estimated Additional Resources, 256 000 t U; (2) Cost range US$80-130/kg U -Reasonably Assured Resources, 56 000 t U; Estimated Additional Resources, 127 000 t U. Most resources are contained in Proterozoic unconformity-related deposits in the Alligator Rivers uranium field in the Northern Territory (Jabiluka, Ranger, Koongarra, Nabarlek deposits) and the Proterozoic stratabound deposit at Olympic Dam on the Stuart Shelf in South Australia

  8. Human Resource Development in Hybrid Libraries

    OpenAIRE

    Prakasan, E. R.; Swarna, T.; Vijai Kumar, *

    2000-01-01

    This paper explores the human resources and development implications in hybrid libraries. Due to technological changes in libraries, which is a result of the proliferation of electronic resources, there has been a shift in workloads and workflow, requiring staff with different skills and educational backgrounds. Training of staff at all levels in information technology is the key to manage change, alleviate anxiety in the workplace and assure quality service in the libraries. Staff developmen...

  9. Modeling of the non isothermal and non isobaric transformations kinetics. Application to the kaolinite de-hydroxylation and to the tri-uranium octo-oxide reduction by hydrogen

    International Nuclear Information System (INIS)

    Perrin, St.

    2002-12-01

    The aim of this work is to be able to describe transformations, occurring when solids and gases are in non isothermal and non isobaric conditions, with kinetic models. A methodology has been used. Two essential processes have to be taken into account: the germination and the growth. The germs are supposed to be formed (at constant temperature and pressure) in the grains surface with a constant velocity by surface unit, (gamma), called germination surface frequency (number of germs.m -2 .s -1 . The growth velocity is characterized by a growth surface reactivity, (phi) (in mol.m -2 .s -1 ). With an appropriate transformation model, it is possible to obtain the variations of (gamma) and (phi) in terms of the temperature and pressure which are then used in the calculation of the velocity in non isothermal and non isobaric conditions. In order to validate the developed method, two reactions have been studied. For the first one, the kaolinite de-hydroxylation, an anisotropic germination-growth model, where the step limiting the growth is a diffusion step, has been developed in order to explain the experimental kinetic curves. Nevertheless the velocity curves calculated from this model do not allow to describe the reaction for some temperature variations. This result shows the difficulty to precisely determine the germination surface frequency what induces an important approximation on the kinetic curves. The second reaction is the tri-uranium octo-oxide reduction by hydrogen. It has been shown that this reaction occurs according to three successive transformations. A kinetic model has been developed for each of these reactions considering germination as instantaneous. At last, in comparing this model with the experimental velocity curves, a very good agreement has been verified as well as for a temperature variation than for a hydrogen partial pressure change during the reaction. (O.M.)

  10. Uptake properties of Ni2+ by nCaO.Al2O3.2SiO2 (n=1-4) prepared from solid-state reaction of kaolinite and calcite.

    Science.gov (United States)

    Jha, Vinay Kumar; Kameshima, Yoshikazu; Nakajima, Akira; Okada, Kiyoshi; MacKenzie, Kenneth J D

    2005-08-31

    A series of nCaO.Al2O3.2SiO2 samples (n=1-4) were prepared by solid-state reaction of mechanochemically treated mixtures of kaolinite and calcite fired at 600-1000 degrees C for 24 h. All the samples were X-ray amorphous after firing at 600-800 degrees C but had crystallized by 900 degrees C. The main crystalline phases were anorthite (n=1), gehlenite (n=2 and 3) and larnite (n=4). The uptake of Ni2+ by nCaO.Al2O3.2SiO2 samples fired at 800 and 900 degrees C was investigated at room temperature using solutions with initial Ni2+ concentrations of 0.1-50 mmol/l. Amorphous samples (fired at 800 degrees C) showed a higher Ni2+ uptake capacity than crystalline samples (fired at 900 degrees C). Ni2+ uptake was found to increase with increasing of CaO content. Amorphous 4CaO.Al2O3.2SiO2 showed the highest Ni2+ uptake capacity (about 9 mmol/g). The Ni2+ uptake abilities of the present samples are higher than those of other materials reported in the literature. Since the sorbed Ni2+/released Ca2+ ratios of these samples are close to unity, ion replacement of Ni2+ for Ca2+ is thought to be the principal mechanism of Ni2+ uptake by the present samples.

  11. Students developing resources for students.

    Science.gov (United States)

    Pearce, Michael; Evans, Darrell

    2012-06-01

    The development of new technologies has provided medical education with the ability to enhance the student learning experience and meet the needs of changing curricula. Students quickly adapt to using multimedia learning resources, but these need to be well designed, learner-centred and interactive for students to become significantly engaged. One way to ensure that students become committed users and that resources become distinct elements of the learning cycle is to involve students in resource design and production. Such an approach enables resources to accommodate student needs and preferences, but also provides opportunities for them to develop their own teaching and training skills. The aim of the medical student research project was to design and produce an electronic resource that was focused on a particular anatomical region. The views of other medical students were used to decide what features were suitable for inclusion and the resulting package contained basic principles and clinical relevance, and used a variety of approaches such as images of cadaveric material, living anatomy movies and quizzes. The completed package was assessed using a survey matrix and found to compare well with commercially available products. Given the ever-diversifying arena of multimedia instruction and the ability of students to be fully conversant with technology, this project demonstrates that students are ideal participants and creators of multimedia resources. It is hoped that such an approach will help to further develop the skill base of students, but will also provide an avenue of developing packages that are student user friendly, and that are focused towards particular curricula requirements. © Blackwell Publishing Ltd 2012.

  12. Electronic Commerce

    Directory of Open Access Journals (Sweden)

    Slavko Đerić

    2016-12-01

    Full Text Available Electronic commerce can be defined in different ways. Any definition helps to understand and explain that concept as better as possible.. Electronic commerce is a set of procedures and technologies that automate the tasks of financial transactions using electronic means. Also, according to some authors, electronic commerce is defined as a new concept, which is being developed and which includes process of buying and selling or exchanging products, services or information via computer networks, including the Internet. Electronic commerce is not limited just to buying and selling, but it also includes all pre-sales and after-sales ongoing activities along the supply chain. Introducing electronic commerce, using the Internet and Web services in business, realizes the way to a completely new type of economy - internet economy.

  13. Advanced Electronics

    Science.gov (United States)

    2017-07-21

    AFRL-RV-PS- AFRL-RV-PS- TR-2017-0114 TR-2017-0114 ADVANCED ELECTRONICS Ashwani Sharma 21 Jul 2017 Interim Report APPROVED FOR PUBLIC RELEASE...NUMBER Advanced Electronics 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62601F 6. AUTHOR(S) 5d. PROJECT NUMBER 4846 Ashwani Sharma 5e. TASK NUMBER...Approved for public release; distribution is unlimited. (RDMX-17-14919 dtd 20 Mar 2018) 13. SUPPLEMENTARY NOTES 14. ABSTRACT The Space Electronics

  14. Electron spectroscopy

    International Nuclear Information System (INIS)

    Hegde, M.S.

    1979-01-01

    An introduction to the various techniques in electron spectroscopy is presented. These techniques include: (1) UV Photoelectron spectroscopy, (2) X-ray Photoelectron spectroscopy, (3) Auger electron spectroscopy, (4) Electron energy loss spectroscopy, (5) Penning ionization spectroscopy and (6) Ion neutralization spectroscopy. The radiations used in each technique, the basis of the technique and the special information obtained in structure determination in atoms and molecules by each technique are summarised. (A.K.)

  15. Polymer electronics

    CERN Document Server

    Hsin-Fei, Meng

    2013-01-01

    Polymer semiconductor is the only semiconductor that can be processed in solution. Electronics made by these flexible materials have many advantages such as large-area solution process, low cost, and high performance. Researchers and companies are increasingly dedicating time and money in polymer electronics. This book focuses on the fundamental materials and device physics of polymer electronics. It describes polymer light-emitting diodes, polymer field-effect transistors, organic vertical transistors, polymer solar cells, and many applications based on polymer electronics. The book also disc

  16. Electronics Industry

    National Research Council Canada - National Science Library

    Bell, Robert; Carroll-Garrison, Martina; Donovan, Daniel; Fisher, John; Guemmer, Paul; Harms, Robert; Kelly, Timothy; Love, Mattie; McReynolds, James; Ward, Ralph

    2006-01-01

    .... Government action to preserve strategic access to semiconductor producers is clearly needed to ensure DoD electronic systems can be built without compromising sensitive technology, though every...

  17. Microfluidic electronics.

    Science.gov (United States)

    Cheng, Shi; Wu, Zhigang

    2012-08-21

    Microfluidics, a field that has been well-established for several decades, has seen extensive applications in the areas of biology, chemistry, and medicine. However, it might be very hard to imagine how such soft microfluidic devices would be used in other areas, such as electronics, in which stiff, solid metals, insulators, and semiconductors have previously dominated. Very recently, things have radically changed. Taking advantage of native properties of microfluidics, advances in microfluidics-based electronics have shown great potential in numerous new appealing applications, e.g. bio-inspired devices, body-worn healthcare and medical sensing systems, and ergonomic units, in which conventional rigid, bulky electronics are facing insurmountable obstacles to fulfil the demand on comfortable user experience. Not only would the birth of microfluidic electronics contribute to both the microfluidics and electronics fields, but it may also shape the future of our daily life. Nevertheless, microfluidic electronics are still at a very early stage, and significant efforts in research and development are needed to advance this emerging field. The intention of this article is to review recent research outcomes in the field of microfluidic electronics, and address current technical challenges and issues. The outlook of future development in microfluidic electronic devices and systems, as well as new fabrication techniques, is also discussed. Moreover, the authors would like to inspire both the microfluidics and electronics communities to further exploit this newly-established field.

  18. Electron holography

    CERN Document Server

    Tonomura, Akira

    1993-01-01

    Holography was devised for breaking through the resolution limit of electron microscopes The advent of a "coherent" field emission electron beam has enabled the use of Electron Holography in various areas of magnetic domain structures observation, fluxon observation in superconductors, and fundamental experiments in physics which have been inaccessible using other techniques After examining the fundamentals of electron holography and its applications to the afore mentioned fields, a detailed discussion of the Aharonov-Bohm effect and the related experiments is presented Many photographs and illustrations are included to elucidate the text

  19. Electronic Publishing Approaches to Curriculum: Videotex, Teletext and Databases.

    Science.gov (United States)

    Aumente, Jerome

    1986-01-01

    Describes the Journalism Resources Institute (JRI) of Rutgers University in terms of its administrative organization, computer resources, computer facilities use, involvement in electronic publishing, use of the Dow Jones News/Retrieval Database, curricular options, and professional continuing education. (AYC)

  20. When resources get sparse

    DEFF Research Database (Denmark)

    Graungaard, Anette Hauskov; Andersen, John Sahl; Skov, Liselotte

    2011-01-01

    resources through positive cognitive reappraisals of their circumstances, the consequences of those circumstances and their coping possibilities. Nine main coping strategies were identified constituting transformative pathways in resource-creation. A theory of resource-creation is proposed as an addition...... coped with parenting a disabled child and how they maintained their energy and personal resources. We explored parents' experiences, coping and resources over a two-year period after their child was diagnosed with a severely disabling condition using a qualitative, longitudinal approach. Findings were...... to the current understanding of coping and the role of positive emotions. Coping and resources were found to be closely interrelated and portals of intervention are discussed....

  1. The electron

    International Nuclear Information System (INIS)

    Hestenes, David; Weingartshofer, Antonio

    1991-01-01

    The stupendous successes of the Dirac equation and quantum electro-dynamics have established the electron as the best understood of the fundamental constituents of matter. Nevertheless, physicists agree that the electron still has secrets to reveal. Moreover, powerful new theoretical and experimental tools for probing those secrets have been sharpened during the last decade. This workshop was organized to bring theorists and experimentalists together to discuss their common goal of knowing the electron. Present state and future prospects for progress toward that goal are here described. The theoretical papers encompass a wide range of views on the electron. Several argue that the 'Zitter-bewegung' is more than a mathematical peculiarity of the Dirac equation, that it may well be a real physical phenomenon and worthy of serious study, theoretically and experimentally. Besides generating the electron spin and magnetic moment, the 'Zitterbewegung' may be a vital clue to electron structure and self-interaction. Some of the papers employ a radical new formulation of the Dirac theory which reveals a hidden geo-metric structure in the theory that supports a 'Zitterbewegung' inter-pretation. For the last half century the properties of electrons have been probed primarily by scattering experiments at ever higher energies. Recently, however, two powerful new experimental techniques have emerged capable of giving alternative experimental views of the electron. First, techniques for confining single electrons for long term study have led to the most accurate measurements of the electron magnetic moment. Second, the interaction of high intensity laser fields with atoms and electrons have revealed striking new phenomena such as multiphoton ionization. refs.; figs.; tabs

  2. Sustainable polymers from renewable resources.

    Science.gov (United States)

    Zhu, Yunqing; Romain, Charles; Williams, Charlotte K

    2016-12-14

    Renewable resources are used increasingly in the production of polymers. In particular, monomers such as carbon dioxide, terpenes, vegetable oils and carbohydrates can be used as feedstocks for the manufacture of a variety of sustainable materials and products, including elastomers, plastics, hydrogels, flexible electronics, resins, engineering polymers and composites. Efficient catalysis is required to produce monomers, to facilitate selective polymerizations and to enable recycling or upcycling of waste materials. There are opportunities to use such sustainable polymers in both high-value areas and in basic applications such as packaging. Life-cycle assessment can be used to quantify the environmental benefits of sustainable polymers.

  3. Electron Microscopy Observation of Biomineralization within Wood Tissues of Kurogaki

    Directory of Open Access Journals (Sweden)

    Kazue Tazaki

    2017-07-01

    Full Text Available Interactions between minerals and microorganisms play a crucial role in living wood tissues. However, living wood tissues have never been studied in the field. Fortunately, we found several kurogaki (black persimmon; Diospyros kaki trees at Tawara in Kanazawa, Ishikawa, Japan. Here, we report the characterization of kurogaki based on scanning electron microscopy equipped with energy-dispersive spectroscopy (SEM-EDS and transmission electron microscopy (TEM, associated with inductively coupled plasma-mass spectrometry (ICP-MS analyses, X-ray fluorescence analyses (XRF and X-ray powder diffraction (XRD analyses. This study aims to illustrate the ability of various microorganisms associated with biominerals within wood tissues of kurogaki, as shown by SEM-EDS elemental content maps and TEM images. Kurogaki grows very slowly and has extremely hard wood, known for its striking black and beige coloration, referred to as a “peacock pattern”. However, the scientific data for kurogaki are very limited. The black “peacock pattern” of the wood mainly comprises cellulose and high levels of crystal cristobalite. As per the XRD results, the black taproot contains mineralized 7 Å clays (kaolinite, cellulose, apatite and cristobalite associated with many microorganisms. The chemical compositions of the black and beige portions of the black persimmon tree were obtained by ICP-MS analyses. Particular elements such as abundant Ca, Mg, K, P, Mn, Ba, S, Cl, Fe, Na, and Al were concentrated in the black region, associated with Pb and Sr elements. SEM-EDS semi-qualitative analyses of kurogaki indicated an abundance of P and Ca in microorganisms in the black region, associated with Pb, Sr, S, Mn, and Mg elements. On the other hand, XRF and XRD mineralogical data showed that fresh andesite, weathered andesite, and the soils around the roots of kurogaki correlate with biomineralization of the black region in kurogaki roots, showing clay minerals (kaolinite and

  4. Solar Resource Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Renne, D.; George, R.; Wilcox, S.; Stoffel, T.; Myers, D.; Heimiller, D.

    2008-02-01

    This report covers the solar resource assessment aspects of the Renewable Systems Interconnection study. The status of solar resource assessment in the United States is described, and summaries of the availability of modeled data sets are provided.

  5. Hydrography - Water Resources

    Data.gov (United States)

    NSGIC Education | GIS Inventory — A Water Resource is a DEP primary facility type related to the Water Use Planning Program. The sub-facility types related to Water Resources that are included are:...

  6. Current Resource Imagery Projects

    Data.gov (United States)

    Farm Service Agency, Department of Agriculture — Map showing coverage of current Resource imagery projects. High resolution/large scale Resource imagery is typically acquired for the U.S. Forest Service and other...

  7. Vermont Natural Resources Atlas

    Data.gov (United States)

    Vermont Center for Geographic Information — The purpose of the�Natural Resources Atlas�is to provide geographic information about environmental features and sites that the Vermont Agency of Natural Resources...

  8. Resources, Technology, and Strategy

    DEFF Research Database (Denmark)

    Resources, Technology and Strategy brings together contributors from Europe, North America and Asia to consider the strategic relationship between technology and other resources, such as production capabilities, marketing prowess, finance and organisational culture. Throughout the book...

  9. Printed Electronics

    Science.gov (United States)

    Korkut, Sibel (Inventor); Chiang, Katherine S. (Inventor); Crain, John M. (Inventor); Aksay, Ilhan A. (Inventor); Lettow, John S. (Inventor); Chen, Chuan-Hua (Inventor); Prud'Homme, Robert K. (Inventor)

    2018-01-01

    Printed electronic device comprising a substrate onto at least one surface of which has been applied a layer of an electrically conductive ink comprising functionalized graphene sheets and at least one binder. A method of preparing printed electronic devices is further disclosed.

  10. Defense Human Resources Activity > PERSEREC

    Science.gov (United States)

    Skip to main content (Press Enter). Toggle navigation Defense Human Resources Activity Search Search Defense Human Resources Activity: Search Search Defense Human Resources Activity: Search Defense Human Resources Activity U.S. Department of Defense Defense Human Resources Activity Overview

  11. Cultural Resource Predictive Modeling

    Science.gov (United States)

    2017-10-01

    CR cultural resource CRM cultural resource management CRPM Cultural Resource Predictive Modeling DoD Department of Defense ESTCP Environmental...resource management ( CRM ) legal obligations under NEPA and the NHPA, military installations need to demonstrate that CRM decisions are based on objective...maxim “one size does not fit all,” and demonstrate that DoD installations have many different CRM needs that can and should be met through a variety

  12. Reasoning abstractly about resources

    Science.gov (United States)

    Clement, B.; Barrett, A.

    2001-01-01

    r describes a way to schedule high level activities before distributing them across multiple rovers in order to coordinate the resultant use of shared resources regardless of how each rover decides how to perform its activities. We present an algorithm for summarizing the metric resource requirements of an abstract activity based n the resource usages of its potential refinements.

  13. Save Our Water Resources.

    Science.gov (United States)

    Bromley, Albert W.

    The purpose of this booklet, developed as part of Project SOAR (Save Our American Resources), is to give Scout leaders some facts about the world's resources, the sources of water pollution, and how people can help in obtaining solutions. Among the topics discussed are the world's water resources, the water cycle, water quality, sources of water…

  14. The cellulose resource matrix

    NARCIS (Netherlands)

    Keijsers, E.R.P.; Yilmaz, G.; Dam, van J.E.G.

    2013-01-01

    The emerging biobased economy is causing shifts from mineral fossil oil based resources towards renewable resources. Because of market mechanisms, current and new industries utilising renewable commodities, will attempt to secure their supply of resources. Cellulose is among these commodities, where

  15. Ohio Water Resources Council

    Science.gov (United States)

    Ohio.gov State Agencies | Online Services Twitter YouTube EPA IMAGE Ohio Water Resources Committee Ohio enjoys abundant water resources. Few states enjoy as many streams, rivers, lakes and wetlands as Ohio. Numerous agencies and organizations are involved in protecting Ohio's valuable water resources

  16. Electronic Information – Threat or Challenge to Librarians and ...

    African Journals Online (AJOL)

    Electronic Information – Threat or Challenge to Librarians and Library Buildings. ... electronic resources because as new things and methods emerge, they exist ... that world trends in the paper industry and Internet use do not justify the fears ...

  17. Resources to Manage a Private Practice.

    Science.gov (United States)

    Aigner, John; Cheek, Fredricka; Donati, Georgia; Zuravicky, Dori

    1997-01-01

    Includes four theme articles: "The Digital Toolkit: Electronic Necessities for Private Practice" (John Aigner); "Organizing a Private Practice: Forms, Fees, and Physical Set-up (Fredricka Cheek); "Career Development Resources: Guidelines for Setting Up a Private Practice Library" (Georgia Donati); and "Books to…

  18. Digital electronics

    CERN Document Server

    Morris, John

    2013-01-01

    An essential companion to John C Morris's 'Analogue Electronics', this clear and accessible text is designed for electronics students, teachers and enthusiasts who already have a basic understanding of electronics, and who wish to develop their knowledge of digital techniques and applications. Employing a discovery-based approach, the author covers fundamental theory before going on to develop an appreciation of logic networks, integrated circuit applications and analogue-digital conversion. A section on digital fault finding and useful ic data sheets completes th

  19. Electronic diagrams

    CERN Document Server

    Colwell, Morris A

    1976-01-01

    Electronic Diagrams is a ready reference and general guide to systems and circuit planning and in the preparation of diagrams for both newcomers and the more experienced. This book presents guidelines and logical procedures that the reader can follow and then be equipped to tackle large complex diagrams by recognition of characteristic 'building blocks' or 'black boxes'. The goal is to break down many of the barriers that often seem to deter students and laymen in learning the art of electronics, especially when they take up electronics as a spare time occupation. This text is comprised of nin

  20. Polymer electronics

    CERN Document Server

    Geoghegan, Mark

    2013-01-01

    Polymer electronics is the science behind many important new developments in technology, such as the flexible electronic display (e-ink) and many new developments in transistor technology. Solar cells, light-emitting diodes, and transistors are all areas where plastic electronics is likely to, or is already having, a serious impact on our daily lives. With polymer transistors and light-emitting diodes now being commercialised, there is a clear need for a pedagogic text thatdiscusses the subject in a clear and concise fashion suitable for senior undergraduate and graduate students. The content

  1. Starting electronics

    CERN Document Server

    Brindley, Keith

    2005-01-01

    Starting Electronics is unrivalled as a highly practical introduction for hobbyists, students and technicians. Keith Brindley introduces readers to the functions of the main component types, their uses, and the basic principles of building and designing electronic circuits. Breadboard layouts make this very much a ready-to-run book for the experimenter; and the use of multimeter, but not oscilloscopes, puts this practical exploration of electronics within reach of every home enthusiast's pocket. The third edition has kept the simplicity and clarity of the original. New material

  2. Stretchable electronics

    CERN Document Server

    Someya, Takao

    2012-01-01

    With its comprehensive coverage this handbook and ready reference brings together some of the most outstanding scientists in the field to lay down the undisputed knowledge on how to make electronics stretchable.As such, it focuses on gathering and evaluating the materials, designs, models and technologies that enable the fabrication of fully elastic electronic devices which can sustain high strain. Furthermore, it provides a review of those specific applications that directly benefit from highly compliant electronics, including transistors, photonic devices and sensors. In addition to stre

  3. Electron optics

    CERN Document Server

    Grivet, Pierre; Bertein, F; Castaing, R; Gauzit, M; Septier, Albert L

    1972-01-01

    Electron Optics, Second English Edition, Part I: Optics is a 10-chapter book that begins by elucidating the fundamental features and basic techniques of electron optics, as well as the distribution of potential and field in electrostatic lenses. This book then explains the field distribution in magnetic lenses; the optical properties of electrostatic and magnetic lenses; and the similarities and differences between glass optics and electron optics. Subsequent chapters focus on lens defects; some electrostatic lenses and triode guns; and magnetic lens models. The strong focusing lenses and pris

  4. Electronic identity

    CERN Document Server

    de Andrade, Norberto Nuno Gomes; Argles, David

    2014-01-01

    With the increasing availability of electronic services, security and a reliable means by which identity is verified is essential.Written by Norberto Andrade the first chapter of this book provides an overview of the main legal and regulatory aspects regarding electronic identity in Europe and assesses the importance of electronic identity for administration (public), business (private) and, above all, citizens. It also highlights the role of eID as a key enabler of the economy.In the second chapter Lisha Chen-Wilson, David Argles, Michele Schiano di Zenise and Gary Wills discuss the user-cent

  5. Self managing experiment resources

    International Nuclear Information System (INIS)

    Stagni, F; Ubeda, M; Charpentier, P; Tsaregorodtsev, A; Romanovskiy, V; Roiser, S; Graciani, R

    2014-01-01

    Within this paper we present an autonomic Computing resources management system, used by LHCb for assessing the status of their Grid resources. Virtual Organizations Grids include heterogeneous resources. For example, LHC experiments very often use resources not provided by WLCG, and Cloud Computing resources will soon provide a non-negligible fraction of their computing power. The lack of standards and procedures across experiments and sites generated the appearance of multiple information systems, monitoring tools, ticket portals, etc... which nowadays coexist and represent a very precious source of information for running HEP experiments Computing systems as well as sites. These two facts lead to many particular solutions for a general problem: managing the experiment resources. In this paper we present how LHCb, via the DIRAC interware, addressed such issues. With a renewed Central Information Schema hosting all resources metadata and a Status System (Resource Status System) delivering real time information, the system controls the resources topology, independently of the resource types. The Resource Status System applies data mining techniques against all possible information sources available and assesses the status changes, that are then propagated to the topology description. Obviously, giving full control to such an automated system is not risk-free. Therefore, in order to minimise the probability of misbehavior, a battery of tests has been developed in order to certify the correctness of its assessments. We will demonstrate the performance and efficiency of such a system in terms of cost reduction and reliability.

  6. Resource Structuring and Ambidexterity

    DEFF Research Database (Denmark)

    Ma, Yucheng; Li, Peter Ping

    -shaped effect on organizational ambidexterity in new ventures. Further, because of the traditional culture and economic transition characteristics, new ventures actively leverage managerial ties as key social relations to obtain special resources or nurture business transactions. We propose that ties with other......Focusing on how resource structuring mechanisms and managerial ties influence organizational ambidexterity of new ventures in emerging economy, this study explores the effects of resource structuring mechanisms (i.e., resource acquiring and resource accumulating) on organizational ambidexterity....... It further examines the moderating effects of managerial ties, (i.e., ties with other firms and ties with the government) on the above relationships. Survey data from China¡¯s 202 new ventures demonstrates that the resource acquiring has an inverted U-shaped effect whereas the resource accumulating has a U...

  7. Looking for Guidelines for the Production of Electronic Textbooks.

    Science.gov (United States)

    Landoni, M.; Wilson, R.; Gibb, F.

    2001-01-01

    Reports the results of two studies of electronic book production, including production on the World Wide Web, and explains EBONI (Electronic Books On-screen Interface) that focuses on the evaluation of electronic resources and compiling guidelines for publishing electronic materials on the Internet for the United Kingdom higher education…

  8. Paper electronics.

    Science.gov (United States)

    Tobjörk, Daniel; Österbacka, Ronald

    2011-05-03

    Paper is ubiquitous in everyday life and a truly low-cost substrate. The use of paper substrates could be extended even further, if electronic applications would be applied next to or below the printed graphics. However, applying electronics on paper is challenging. The paper surface is not only very rough compared to plastics, but is also porous. While this is detrimental for most electronic devices manufactured directly onto paper substrates, there are also approaches that are compatible with the rough and absorptive paper surface. In this review, recent advances and possibilities of these approaches are evaluated and the limitations of paper electronics are discussed. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Electron Microprobe

    Data.gov (United States)

    Federal Laboratory Consortium — The JEOL JXA-8600 is a conventional hairpin filament thermal emission electron microprobe that is more than 20 years old. It is capable of performing qualitative and...

  10. Electronic Aggression

    Centers for Disease Control (CDC) Podcasts

    Aggression is no longer limited to the school yard. New forms of electronic media, such as blogs, instant messaging, chat rooms, email, text messaging, and the internet are providing new arenas for youth violence to occur.

  11. Electron Emitters

    National Research Council Canada - National Science Library

    Tzeng, Yonhua

    2002-01-01

    When two carbon-nanotube coated electrodes are placed at a small distance from each other, electron emission from carbon nanotubes allows a DC or AC electrical current to flow between these two electrodes...

  12. Electronic plants

    Science.gov (United States)

    Stavrinidou, Eleni; Gabrielsson, Roger; Gomez, Eliot; Crispin, Xavier; Nilsson, Ove; Simon, Daniel T.; Berggren, Magnus

    2015-01-01

    The roots, stems, leaves, and vascular circuitry of higher plants are responsible for conveying the chemical signals that regulate growth and functions. From a certain perspective, these features are analogous to the contacts, interconnections, devices, and wires of discrete and integrated electronic circuits. Although many attempts have been made to augment plant function with electroactive materials, plants’ “circuitry” has never been directly merged with electronics. We report analog and digital organic electronic circuits and devices manufactured in living plants. The four key components of a circuit have been achieved using the xylem, leaves, veins, and signals of the plant as the template and integral part of the circuit elements and functions. With integrated and distributed electronics in plants, one can envisage a range of applications including precision recording and regulation of physiology, energy harvesting from photosynthesis, and alternatives to genetic modification for plant optimization. PMID:26702448

  13. Electronic Elections

    DEFF Research Database (Denmark)

    Schürmann, Carsten

    2009-01-01

    Electronic voting technology is a two edged sword. It comes with many risks but brings also many benefits. Instead of flat out rejecting the technology as uncontrollably dangerous, we advocate in this paper a different technological angle that renders electronic elections trustworthy beyond...... the usual levels of doubt. We exploit the trust that voters currently have into the democratic process and model our techniques around that observation accordingly. In particular, we propose a technique of trace emitting computations to record the individual steps of an electronic voting machine...... for a posteriori validation on an acceptably small trusted computing base. Our technology enables us to prove that an electronic elections preserves the voter’s intent, assuming that the voting machine and the trace verifier are independent....

  14. Electronic commerce

    OpenAIRE

    Zvolánková, Pavla

    2010-01-01

    The thesis deals with a description of electronic commerce from its beginning up to present situation in this area. It explains basic terms connected with electronic commerce and it summarizes the relevant legislation. Moreover it describes e-contracts and rights and duties of both contractual parties. The main view is the view of Internet retailer, which is reflected in the practical part focused on concrete problems of retailers.

  15. Printed Electronics

    Science.gov (United States)

    Wade, Jessica; Hollis, Joseph Razzell; Wood, Sebastian

    2018-04-01

    The combination of printing technology with manufacturing electronic devices enables a new paradigm of printable electronics, where 'smart' functionality can be readily incorporated into almost any product at low cost. Over recent decades, rapid progress has been made in this field, which is now emerging into the industrial andcommercial realm. However, successful development and commercialisation on a large scale presents some significant technical challenges. For fully-printable electronic systems, all the component parts must be deposited from solutions (inks), requiring the development of new inorganic, organic and hybrid materials.A variety of traditional printing techniques are being explored and adapted forprinting these new materials in ways that result in the best performing electronicdevices. Whilst printed electronics research has initially focused on traditional typesof electronic device such as light-emitting diodes, transistors, and photovoltaics, it is increasingly apparent that a much wider range of applications can be realised. The soft and stretchable nature of printable materials makes them perfect candidates forbioelectronics, resulting in a wealth of research looking at biocompatible printable inks and biosensors. Regardless of application, the properties of printed electronicmaterials depend on the chemical structures, processing conditions, device architecture,and operational conditions, the complex inter-relationships of which aredriving ongoing research. We focus on three particular 'hot topics', where attention is currently focused: novel materials, characterisation techniques, and device stability. With progress advancing very rapidly, printed electronics is expected to grow over the next decade into a key technology with an enormous economic and social impact.

  16. Where Doctors Read Health Information Resources and Their ...

    African Journals Online (AJOL)

    Resources Media Preferences. Obianuju E. ... The survey research design was adopted for the study. ... media of assessing health information are the internet, electronic databases, textbooks, journals and .... for Social Sciences (SPSS).

  17. Improving the Status of Human and Material Resources in Public ...

    African Journals Online (AJOL)

    Improving the Status of Human and Material Resources in Public Primary School in Oyo States ... the Millennium Development Goals project in the State. ... libraries, well-equipped first aid centres, adequate electronically projected instructional ...

  18. Lightning Safety Tips and Resources

    Science.gov (United States)

    ... Services Careers Contact Us Glossary Safety National Program Lightning Safety Tips and Resources Weather.gov > Safety > Lightning Safety Tips and Resources Lightning Resources Lightning strikes ...

  19. Numerical simulation of transient moisture and temperature distribution in polycarbonate and aluminum electronic enclosures

    DEFF Research Database (Denmark)

    Shojaee Nasirabadi, Parizad; Jabbaribehnam, Mirmasoud; Hattel, Jesper Henri

    2016-01-01

    The challenge of developing a reliable electronic product requires huge amounts of resources and knowledge. Temperature and thermal features directly affect the life of electronic products. Furthermore, moisture can be damaging for electronic components. Nowadays, computational fluid dynamics (CF...

  20. Risk Profile May Affect Search Process but Not Results. A review of: McKibbon, K. Ann, Douglas B. Fridsma, and Rebecca S. Crowley. “How Primary Care Physicians’ Attitudes Toward Risk and Uncertainty Affect Their Use of Electronic Information Resources.” Journal of the Medical Library Association 95.2 (2007: 138‐46, e49‐50. 10 Nov. 2007 .

    Directory of Open Access Journals (Sweden)

    Gale G. Hannigan

    2007-12-01

    Full Text Available Objective – To compare the use, in terms of process and outcomes, of electronic information resources by primary care physicians with different risk profiles and comfort with uncertainty.Design – Survey, and observation using “think‐aloud” method.Setting – Physicians’ offices.Subjects – Canadian and U.S. primary carephysicians who report seeing patients in clinic settings.Methods – Volunteers were recruited from personal contacts and the list of physicianswho rate current studies for the McMaster Online Rating of Evidence (MORE project. Physicians completed the Pearson scale to measure attitude toward risk and the Gerrity scale to measure comfort with uncertainty, and those who scored at the extremes of each of these two scales were included in the study (n=25, resulting in four groups (risk‐seeking, risk‐avoiding, uncertainty‐stressed, uncertainty unstressed. One researcher observed each of these physicians in their offices for an hour during which they completed questionnaires about their computer skills and familiarity with resources, answered multiple‐choice clinical questions, and indicated level of certainty with regard to those answers (scale of 0 to 100%. Physicians also chose two of the clinical questions to answer using their own resources. The think‐aloud method was employed, and transcripts were coded and analyzed.Main results – The study analysis included two comparisons: risk‐seeking (11 subjects versus risk‐avoiding (11 subjects physicians,and uncertainty‐stressed (11 subjects versus uncertainty‐unstressed (10 subjects physicians. Most physicians were included in both sets of analyses. The researchers found no association of risk attitude and uncertainty stress with computer skills nor with familiarity and use of specific information resources (Internet, MEDLINE, PIER, Clinical Evidence, and UpToDate. No differences were found for the following outcomes: time spent searching, answers correct

  1. World energy resources

    Directory of Open Access Journals (Sweden)

    Clerici A.

    2015-01-01

    Full Text Available As energy is the main “fuel” for social and economic development and since energy-related activities have significant environmental impacts, it is important for decision-makers to have access to reliable and accurate data in an user-friendly format. The World Energy Council (WEC has for decades been a pioneer in the field of energy resources and every three years publishes its flagship report Survey of Energy Resources. A commented analysis in the light of latest data summarized in such a report, World Energy Resources (WER 2013, is presented together with the evolution of the world energy resources over the last twenty years.

  2. World energy resources

    Science.gov (United States)

    Clerici, A.; Alimonti, G.

    2015-08-01

    As energy is the main "fuel" for social and economic development and since energy-related activities have significant environmental impacts, it is important for decision-makers to have access to reliable and accurate data in an user-friendly format. The World Energy Council (WEC) has for decades been a pioneer in the field of energy resources and every three years publishes its flagship report Survey of Energy Resources. A commented analysis in the light of latest data summarized in such a report, World Energy Resources (WER) 2013, is presented together with the evolution of the world energy resources over the last twenty years.

  3. Sharing network resources

    CERN Document Server

    Parekh, Abhay

    2014-01-01

    Resource Allocation lies at the heart of network control. In the early days of the Internet the scarcest resource was bandwidth, but as the network has evolved to become an essential utility in the lives of billions, the nature of the resource allocation problem has changed. This book attempts to describe the facets of resource allocation that are most relevant to modern networks. It is targeted at graduate students and researchers who have an introductory background in networking and who desire to internalize core concepts before designing new protocols and applications. We start from the fun

  4. 2005 resource options report

    International Nuclear Information System (INIS)

    Morris, T.

    2005-01-01

    This resource options report (ROR) fulfils regulatory requirements in British Columbia's two-year resource planning process. It identifies a wide range of resources and technologies that could be used to meet BC Hydro's future electricity demand. As such, it facilitates a transparent public review of resource options which include both supply-side and demand-side options. The resource options that will be used in the 2005 integrated electricity plan (IEP) were characterized. This ROR also documents where there is a general agreement or disagreement on the resource type characterization, based on the First Nations and Stakeholder engagement. BC Hydro used current information to provide realistic ranges on volume and cost to characterize environmental and social attributes. The BC Hydro system was modelled to assess the benefit and cost of various resource options. The information resulting from this ROR and IEP will help in making decisions on how to structure competitive acquisition calls and to determine the level of transmission services needed to advance certain BC Hydro projects. The IEP forecasts the nature and quantity of domestic resources required over the next 20 years. A strategic direction on how those needs will be met has been created to guide the management of BC Hydro's energy resources. Supply-side options include near-commercial technologies such as energy storage, ocean waves, tidal, fuel cells and integrated coal gasification combined cycle technology. Supply-side options also include natural gas, coal, biomass, geothermal, wind, and hydro. 120 refs., 39 tabs., 21 figs., 6 appendices

  5. Emotional Intelligence Research within Human Resource Development Scholarship

    Science.gov (United States)

    Farnia, Forouzan; Nafukho, Fredrick Muyia

    2016-01-01

    Purpose: The purpose of this study is to review and synthesize pertinent emotional intelligence (EI) research within the human resource development (HRD) scholarship. Design/methodology/approach: An integrative review of literature was conducted and multiple electronic databases were searched to find the relevant resources. Using the content…

  6. Utilisation of Online Resources among Undergraduates in Nigerian ...

    African Journals Online (AJOL)

    Electronic book (e-book) was mostly utilized as against Ejournals and E-thesis, while mobile phones and cybercafés remain the channels used in accessing online resources. it was discovered that incessant power supply, slow Internet connectivity and lack of time to access the information resources are constraints to ...

  7. Molecular Electronics

    DEFF Research Database (Denmark)

    Jennum, Karsten Stein

    This thesis includes the synthesis and characterisation of organic compounds designed for molecular electronics. The synthesised organic molecules are mainly based on two motifs, the obigo(phenyleneethynylenes) (OPE)s and tetrathiafulvalene (TTF) as shown below. These two scaffolds (OPE and TTF......) are chemically merged together to form cruciform-like structures that are an essential part of the thesis. The cruciform molecules were subjected to molecular conductance measurements to explore their capability towards single-crystal field-effect transistors (Part 1), molecular wires, and single electron......, however, was obtained by a study of a single molecular transistor. The investigated OPE5-TTF compound was captured in a three-terminal experiment, whereby manipulation of the molecule’s electronic spin was possible in different charge states. Thus, we demonstrated how the cruciform molecules could...

  8. Electron tube

    Science.gov (United States)

    Suyama, Motohiro [Hamamatsu, JP; Fukasawa, Atsuhito [Hamamatsu, JP; Arisaka, Katsushi [Los Angeles, CA; Wang, Hanguo [North Hills, CA

    2011-12-20

    An electron tube of the present invention includes: a vacuum vessel including a face plate portion made of synthetic silica and having a surface on which a photoelectric surface is provided, a stem portion arranged facing the photoelectric surface and made of synthetic silica, and a side tube portion having one end connected to the face plate portion and the other end connected to the stem portion and made of synthetic silica; a projection portion arranged in the vacuum vessel, extending from the stem portion toward the photoelectric surface, and made of synthetic silica; and an electron detector arranged on the projection portion, for detecting electrons from the photoelectric surface, and made of silicon.

  9. Spin electronics

    CERN Document Server

    Buhrman, Robert; Daughton, James; Molnár, Stephan; Roukes, Michael

    2004-01-01

    This report is a comparative review of spin electronics ("spintronics") research and development activities in the United States, Japan, and Western Europe conducted by a panel of leading U.S. experts in the field. It covers materials, fabrication and characterization of magnetic nanostructures, magnetism and spin control in magnetic nanostructures, magneto-optical properties of semiconductors, and magnetoelectronics and devices. The panel's conclusions are based on a literature review and a series of site visits to leading spin electronics research centers in Japan and Western Europe. The panel found that Japan is clearly the world leader in new material synthesis and characterization; it is also a leader in magneto-optical properties of semiconductor devices. Europe is strong in theory pertaining to spin electronics, including injection device structures such as tunneling devices, and band structure predictions of materials properties, and in development of magnetic semiconductors and semiconductor heterost...

  10. Electronic Commerce

    Energy Technology Data Exchange (ETDEWEB)

    Laird, N. [NRG Information Services Inc., Calgary, AB (Canada)

    1995-11-01

    The concept of electronic commerce in the gas industry was discussed. It was defined as the integration of communication technology, advanced information processing capability and business standards, to improve effectiveness of the business process. Examples of electronic data interchange from the automotive, airline, and banking industry were given. The objective of using this technology in the gas industry was described as the provision of one electronic facility to make seamless contractual and operational arrangements for moving natural gas across participating pipelines. The benefit of seamless integration - one readily available standard system used by several companies - was highlighted. A list of value-added services such as the free movement of bulletins, directories, nominations,and other documents was provided.

  11. Electron accelerator

    International Nuclear Information System (INIS)

    Abramyan.

    1981-01-01

    The USSR produces an electron accelerator family of a simple design powered straight from the mains. The specifications are given of accelerators ELITA-400, ELITA-3, ELT-2, TEUS-3 and RIUS-5 with maximum electron energies of 0.3 to 5 MeV, a mean power of 10 to 70 kW operating in both the pulsed and the continuous (TEUS-3) modes. Pulsed accelerators ELITA-400 and ELITA-3 and RIUS-5 in which TESLA resonance transformers are used are characterized by their compact size. (Ha)

  12. Electronic cigarette

    OpenAIRE

    Wang, Tao

    2016-01-01

    As we know E-cigarette is becoming increasingly popular all over the world. It is a new product that the most of smoking people would like to buy and use. However, we are not realizing advantages and disadvantages of e-cigarette clearly. My objective was to research the development of electronic cigarette whether it is under control or a good way of marketing. The thesis has two main parts. They include answers to questions what is electronic cigarette and how to manage the whole industry...

  13. Gaseous Electronics Tables, Atoms, and Molecules

    CERN Document Server

    Raju, Gorur Govinda

    2011-01-01

    With the constant emergence of new research and application possibilities, gaseous electronics is more important than ever in disciplines including engineering (electrical, power, mechanical, electronics, and environmental), physics, and electronics. The first resource of its kind, Gaseous Electronics: Tables, Atoms, and Molecules fulfills the author's vision of a stand-alone reference to condense 100 years of research on electron-neutral collision data into one easily searchable volume. It presents most--if not all--of the properly classified experimental results that scientists, researchers,

  14. Reliability criteria selection for integrated resource planning

    International Nuclear Information System (INIS)

    Ruiu, D.; Ye, C.; Billinton, R.; Lakhanpal, D.

    1993-01-01

    A study was conducted on the selection of a generating system reliability criterion that ensures a reasonable continuity of supply while minimizing the total costs to utility customers. The study was conducted using the Institute for Electronic and Electrical Engineers (IEEE) reliability test system as the study system. The study inputs and results for conditions and load forecast data, new supply resources data, demand-side management resource data, resource planning criterion, criterion value selection, supply side development, integrated resource development, and best criterion values, are tabulated and discussed. Preliminary conclusions are drawn as follows. In the case of integrated resource planning, the selection of the best value for a given type of reliability criterion can be done using methods similar to those used for supply side planning. The reliability criteria values previously used for supply side planning may not be economically justified when integrated resource planning is used. Utilities may have to revise and adopt new, and perhaps lower supply reliability criteria for integrated resource planning. More complex reliability criteria, such as energy related indices, which take into account the magnitude, frequency and duration of the expected interruptions are better adapted than the simpler capacity-based reliability criteria such as loss of load expectation. 7 refs., 5 figs., 10 tabs

  15. Greenland and Natural Resources

    DEFF Research Database (Denmark)

    Lyck, Lise

    Greenland policy can delay and maybe change the future of the forecasted development of the use of natural resources. This book is relevant for anyone interested in Greenland in general and the development of Greenland both politically and economically and in relation natural resources....

  16. Resources and Transaction Costs

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    2004-01-01

    resources depends on the propertyrights that she holds to those resources and on the transaction costs of exchanging,defining and protecting the relevant property rights. While transaction costs aremajor sources of value dissipation, value may be created by reducing suchdissipation. Implications for the RBV...

  17. Physical resources and infrastructure

    NARCIS (Netherlands)

    Foeken, D.W.J.; Hoorweg, J.; Foeken, D.W.J.; Obudho, R.A.

    2000-01-01

    This chapter describes the main physical characteristics as well as the main physical and social infrastructure features of Kenya's coastal region. Physical resources include relief, soils, rainfall, agro-ecological zones and natural resources. Aspects of the physical infrastructure discussed are

  18. Renewable material resource potential

    NARCIS (Netherlands)

    van Weenen, H.; Wever, R.; Quist, J.; Tukker, A.; Woudstra, J.; Boons, F.A.A.; Beute, N.

    2010-01-01

    Renewable material resources, consist of complex systems and parts. Their sub-systems and sub-sub-systems, have unique, specific, general and common properties. The character of the use that is made of these resources, depends on the availability of knowledge, experience, methods, tools, machines

  19. Human Resource Construction

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Centering on strategic objective of reform and development,CIAE formulated its objectives in human resource construction for the 13th Five-year Plan period,and achieved new apparent progress in human resource construction in 2015.1 Implementation of"LONGMA Project"

  20. Selected Resources and Bibliography

    Science.gov (United States)

    New Directions for Higher Education, 2011

    2011-01-01

    This chapter provides an annotated bibliography of resources pertaining to international branch campuses (IBCs). This collection of references has been selected to represent the breadth of emerging scholarship on cross-border higher education and is intended to provide further resources on a range of concerns surrounding cross-border higher…