WorldWideScience

Sample records for blends

  1. Blended Learning

    OpenAIRE

    Bauerová, Andrea

    2013-01-01

    This thesis is focused on a new approach of education called blended learning. The history and developement of Blended Learning is described in the first part. Then the methods and tools of Blended Learning are evaluated and compared to the traditional methods of education. At the final part an efficient developement of the educational programs is emphasized.

  2. Blended learning

    DEFF Research Database (Denmark)

    Dau, Susanne

    2016-01-01

    -finding process of navigating different learning environment. Blended learning is conceptualized as an ecological learning process where sociality, mobility, interactionality, structures, spatiality, identity and emotionality are central dimension affiliated to blended learning as way-finding. Based on the......Blended Learning has been implemented, evaluated and researched for the last decades within different educational areas and levels. Blended learning has been coupled with different epistemological understandings and learning theories, but the fundamental character and dimensions of learning in...... blended learning are still insufficient. Moreover, blended learning is a misleading concept described as learning, despite the fact that it fundamentally is an instructional and didactic approach (Oliver & Trigwell, 2005) addressing the learning environment (Inglis, Palipoana, Trenhom & Ward, 2011...

  3. Blended learning

    DEFF Research Database (Denmark)

    Staugaard, Hans Jørgen

    2012-01-01

    Forsøg på at indkredse begrebet blended learning i forbindelse med forberedelsen af projekt FlexVid.......Forsøg på at indkredse begrebet blended learning i forbindelse med forberedelsen af projekt FlexVid....

  4. Blended Learning

    Science.gov (United States)

    Imbriale, Ryan

    2013-01-01

    Teachers always have been and always will be the essential element in the classroom. They can create magic inside four walls, but they have never been able to create learning environments outside the classroom like they can today, thanks to blended learning. Blended learning allows students and teachers to break free of the isolation of the…

  5. Blended Learning

    Science.gov (United States)

    Tucker, Catlin; Umphrey, Jan

    2013-01-01

    Catlin Tucker, author of "Blended Learning in Grades 4-12," is an English language arts teacher at Windsor High School in Sonoma County, CA. In this conversation with "Principal Leadership," she defines blended learning as a formal education program in which a student is engaged in active learning in part online where they…

  6. Blended Learning

    DEFF Research Database (Denmark)

    Gynther, Karsten

    2012-01-01

    Artiklen giver en grundlæggende introduktion til begrebet blended learning og sætter fokus på didaktiske spørgsmål som: Hvad er blended learning? Hvilke forskellige former ser vi i dag i danske uddannelser? Hvorfor udbydes uddannelser i stigende grad i et blended learning format? Hvilke didaktiske...... principper kan man som underviser tage i brug, når man skal designe et blended learning forløb? Hvad er den grundlæggende didaktiske forskel på tilstedeværelsesundervisning og netbaseret undervisning? Og hvilke kritiske perspektiver er det vigtigt at have med, når en uddannelsesinstitution beslutter sig for...... at re-designe traditionel tilstedeværelsesundervisning til blended learning?...

  7. Stockyard blending

    Energy Technology Data Exchange (ETDEWEB)

    Ferretti, C.; Grattarola, G.C. (Italimpianti S.p.A., Genoa (Italy). Bulk Materials Handling Division)

    1991-03-01

    Six computer calculation programs have been developed to simulate the blending process. The integrated system, known as ASPO, has been implemented by Italimpianti for statistical analysis of the blending processes in stockyards. Programs are written in FORTRAN 77 and require a short processing time. The OLOMON program analyzes the content percentages; RAILON analyses the ratio indices; the TRAGEO and TRAMIX programs allow the building of the transverse section of the pipe and create data for subsequent analysis of reclaiming the front; TRATAM and TRARUA enable analysis of the reclaiming of the pile with a barrel and a wheel reclaimer respectively. Results of the application of the blending technique in the iron and steel industry in an iron ore plant and in a coal blending plant in the USSR are given. 1 ref., 25 figs., 1 tab.

  8. Blended learning

    OpenAIRE

    Басава, Ганна Іванаўна; Салаўёў, Павел Леанідавіч

    2015-01-01

    In recent years, the training initiatives in blended learning increased enormously as a result of the different demands to integrate the Information and Communication Technologies (ICT) in educational systems. In Higher Education, the blend approach is highly pursued because of its unique flexibility that allows the teacher to propose, in every situation, more advantageous train- ing solutions for their students, contrary to mandatory classroom in Basic and Secondary schools. It seems that th...

  9. BLEED & BLEND

    OpenAIRE

    Goodfellow, Paul

    2012-01-01

    BLEED & BLEND is an ambient artwork that was commissioned by Digital Media in Newcastle University's Culture Lab, as part of their data visualisation screening project: Data Elements. The aim of the project was to take an unconventional approach to interpreting and displaying scientific data through visual artworks. The work was projected onto Newcastle University's Kings Gate building in Newcastle city centre in October 2012. A useful and succinct description of Ambient Art is found in B...

  10. Effective Blended Learning Techniques

    Science.gov (United States)

    Gill, Deborah

    2009-01-01

    Blended learning is becoming more prevalent in higher education courses. Reasons for blending range from accommodating more students to improving the quality of courses offered. The purpose of this paper is twofold: (1) to discuss student attitudes towards blended courses versus face-to-face versus completely online courses, and (2) to consider…

  11. Blended learning

    OpenAIRE

    Rubens, Wilfred

    2011-01-01

    `Blended learning` во изучувањето на странските јазици нуди голема предност во споредба со другите методи и пристапи. Како концепт тој вклучува обработка на оригинален текст и негова актуeлизација во процесот на учење во комбинација со интернет или напредната технологија во наставата, но користи и аудио и видео снимки од изворни говорници. Во својата наставна дејност анализирам и обработувам видео и аудио текстови од германски изворни говорители преземени од различни веб страници. На овој нач...

  12. A Blended Learning Experience

    Science.gov (United States)

    Gecer, Aynur; Dag, Funda

    2012-01-01

    Blended (hybrid) learning is one of the approaches that is utilized to help students for meaningful learning via information and communication technologies in educational settings. In this study, Computer II Course which is taught in faculties of education was planned and implemented in the form of a blended learning environment. The data were…

  13. Blended Learning Environments and Suggesstions for Blended Learning Design

    OpenAIRE

    Dağ, Funda

    2011-01-01

    The number of studies in blended learning field, which has gained importance by being reinterpreted with the effect of the developments in information and communication technologies, has been increasing recently. There have been many diverse approaches in these studies on the point of defining blended learning and on the point of which components of blended learning environments need blending and how they are blended. The aim of this study is to examine national and international studies in b...

  14. Blended Learning Design

    DEFF Research Database (Denmark)

    Pedersen, Lise

    2015-01-01

    digital materials which can be employed didactically and reused by the teachers. This can also mean that the particular competencies which teaches have in Svendborg can be used at other locations in UCL and disseminated to a larger group of students without further costs. Educational Innovation and...... Learning Resources (EILR) was asked to develop and support the blended learning implementation strategy. EILR is an inter-faculty unit in UCL, which develops and supports digitization and learning approaches in the professional bachelor programme. The paper addresses the potentials and the pitfalls in the...... blended learning implementation strategy. The blended learning implementation strategy contains phases for preparation, development, implementation and evaluation. The preparation phase addresses the importance of goal-setting and includes the winnings and the purpose. The developmental phase looks into...

  15. Blended Learning Environments and Suggesstions for Blended Learning Design

    Directory of Open Access Journals (Sweden)

    Funda DAĞ

    2011-06-01

    Full Text Available The number of studies in blended learning field, which has gained importance by being reinterpreted with the effect of the developments in information and communication technologies, has been increasing recently. There have been many diverse approaches in these studies on the point of defining blended learning and on the point of which components of blended learning environments need blending and how they are blended. The aim of this study is to examine national and international studies in blended learning in higher education and to make suggestions about necessary components for designing an effective blended learning environment. Within this framework the studies on blended learning, which were accessible online, were examined from the perspectives of research methods that were used, preferred e-learning environments and/or e-learning methods, preferred face to face learning/teaching strategies and the methods used in the evaluation of blended learning. In the light of the findings it is seen that blended learning should be regarded as a teaching design approach in order to create effectively blended learning environments and it is hoped that the suggestions made will be lodestar in forming blended learning models for diverse learning fields.

  16. AKRO/SF: Blend System

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Blend was the system used by the NMFS Alaska Regional Office to monitor groundfish catch from 1991 until 2002. The Blend system combined data from industry...

  17. Morphology stabilization of heterogeneous blends

    International Nuclear Information System (INIS)

    A heterogeneous elastomer blend is described, consisting of at least two elastomer components which are cross-linkable by irradiation and having a stabilized morphology formed by subjecting the blend to high energy radiation to a point from below to slightly above the gel dose of the blend. (author)

  18. Theory of polymer blends

    International Nuclear Information System (INIS)

    We have recently developed a new theoretical approach to the study of polymer liquids. The theory is based on the ''reference interaction site model'' (RISM theory) of Chandler and Andersen, which has been successful in describing the structure of small molecule liquids. We have recently extended our polymer RISM theory to the case of polymer blends. In the present investigation we have applied this theory to two special binary blends: (1) the athermal mixture where we isolate structural effects, and (2) the isotopic mixture in which structurally identical polymer chains interact with dissimilar attractive interactions. By studying these two special cases we are able to obtain insights into the molecular factors which control the miscibility in polymer mixtures. 18 refs., 2 figs

  19. Synthesizing optimal waste blends

    International Nuclear Information System (INIS)

    Vitrification of tank wastes to form glass is a technique that will be used for the disposal of high-level waste at Hanford. Process and storage economics show that minimizing the total number of glass logs produced is the key to keeping cost as low as possible. The amount of glass produced can be reduced by blending of the wastes. The optimal way to combine the tanks to minimize the vole of glass can be determined from a discrete blend calculation. However, this problem results in a combinatorial explosion as the number of tanks increases. Moreover, the property constraints make this problem highly nonconvex where many algorithms get trapped in local minima. In this paper the authors examine the use of different combinatorial optimization approaches to solve this problem. A two-stage approach using a combination of simulated annealing and nonlinear programming (NLP) is developed. The results of different methods such as the heuristics approach based on human knowledge and judgment, the mixed integer nonlinear programming (MINLP) approach with GAMS, and branch and bound with lower bound derived from the structure of the given blending problem are compared with this coupled simulated annealing and NLP approach

  20. Blended Learning in English Literature

    OpenAIRE

    Haugestad, Astrid

    2015-01-01

    Abstract Blended Learning This study investigates blended learning used in a course of English Literature and Culture in upper secondary school. It raises the question how the use of blended learning may promote and encourage learning in a course of English literature and culture. The study also compares traditional face-to-face classroom communication with communication mediated by digital artefacts. It has been important to go beyond the strictly technical issues ...

  1. Blended-Learning-Projekte im Unternehmen

    OpenAIRE

    Keller, Miriam; Back, Andrea

    2004-01-01

    Der Arbeitsbericht Blended-Learning-Projekte im Unternehmen liefert einen Beitrag zur Bearbeitung des Themas Blended Learning und liefert dem Leser einen Überblick und erste Anregungen zur Planung, Integration und Gestaltung von Blended-Learning-Konzepten im Unternehmen.

  2. Managing as blended care.

    Science.gov (United States)

    Mintzberg, H

    1994-09-01

    As part of a research project on managerial work based on a new model of the roles, the head nurse of a hospital unit was observed during a working day. Her work is described, with reference especially to the roles of leading, linking, controlling, and doing. Conclusions are drawn about the advantages of a craft style of management as opposed to the more traditional "boss" or professional styles. The author also discusses what those in general management can learn from those in nursing management, which seems best practiced out in the open, on one's feet, as a kind of blended care. PMID:8089715

  3. Blended Learning on Campus

    DEFF Research Database (Denmark)

    Heilesen, Simon; Nielsen, Jørgen Lerche

    2004-01-01

    On the basis of a large-scale project implementing information and communication technology at Roskilde University, Denmark, this paper discusses ways of introducing technology-based blended learning in academic life. We examine some examples of use of systems for computer-mediated collabora......-tive learning and work in Danish Open University education as well as in courses on campus. We further suggest some possi-bilities for using technology in innovative ways, arguing that innovation is to be found, not in isolated instantiations of sys-tems, but in the form of a deliberate integration of all...... relevant ICT-features as a whole into the learning environment....

  4. Blended Learning Improves Science Education.

    Science.gov (United States)

    Stockwell, Brent R; Stockwell, Melissa S; Cennamo, Michael; Jiang, Elise

    2015-08-27

    Blended learning is an emerging paradigm for science education but has not been rigorously assessed. We performed a randomized controlled trial of blended learning. We found that in-class problem solving improved exam performance, and video assignments increased attendance and satisfaction. This validates a new model for science communication and education. PMID:26317458

  5. The Basics of Blended Instruction

    Science.gov (United States)

    Tucker, Catlin R.

    2013-01-01

    Even though many of teachers do not have technology-rich classrooms, the rapidly evolving education landscape increasingly requires them to incorporate technology to customize student learning. Blended learning, with its mix of technology and traditional face-to-face instruction, is a great approach. Blended learning combines classroom learning…

  6. Short fiber reinforced thermoplastic blends

    NARCIS (Netherlands)

    Malchev, P.G.

    2008-01-01

    The present thesis investigates the potential of short fiber reinforced thermoplastic blends, a combination of an immiscible polymer blend and a short fiber reinforced composite, to integrate the easy processing solutions available for short fiber reinforced composites with the high mechanical perfo

  7. Classifying K-12 Blended Learning

    Science.gov (United States)

    Staker, Heather; Horn, Michael B.

    2012-01-01

    The growth of online learning in the K-12 sector is occurring both remotely through virtual schools and on campuses through blended learning. In emerging fields, definitions are important because they create a shared language that enables people to talk about the new phenomena. The blended-learning taxonomy and definitions presented in this paper…

  8. Blended Learning: A Dangerous Idea?

    Science.gov (United States)

    Moskal, Patsy; Dziuban, Charles; Hartman, Joel

    2013-01-01

    The authors make the case that implementation of a successful blended learning program requires alignment of institutional, faculty, and student goals. Reliable and robust infrastructure must be in place to support students and faculty. Continuous evaluation can effectively track the impact of blended learning on students, faculty, and the…

  9. Challenges of blended-learning

    OpenAIRE

    Lugovtsova, Y. D.; Mylnikova, Tatyana Stepanovna

    2014-01-01

    Creation of the virtual environment as an educational resource to increase motivation and inquisition of the students is a great challenge for Russian educational system. The paper considers some issues of blended-learning. Some elements of blended-learning are analyzed through the ways they are implemented in Tomsk Polytechnic University.

  10. Viscoelastic Properties of Polymer Blends

    Science.gov (United States)

    Hong, S. D.; Moacanin, J.; Soong, D.

    1982-01-01

    Viscosity, shear modulus and other viscoelastic properties of multicomponent polymer blends are predicted from behavior of individual components, using a mathematical model. Model is extension of two-component-blend model based on Rouse-Bueche-Zimm theory of polymer viscoelasticity. Extension assumes that probabilities of forming various possible intracomponent and intercomponent entanglements among polymer molecules are proportional to relative abundances of components.

  11. Blend or not to blend: a study investigating faculty members perceptions of blended teaching

    Directory of Open Access Journals (Sweden)

    Mehmet A Ocak

    2010-12-01

    Full Text Available This study examined faculty members’ perceptions of blended teaching from several perspectives. A total of 73 faculty members in Turkish Higher Education context participated in the study by completing an online survey that combined quantitative and qualitative approaches. Based on a data analysis, the faculty members’ perceptions were sorted into six categories: (a satisfaction with blended teaching, (b perceived impact on the role of the faculty, (c perceived impact on student learning, (d perceived impact on student motivation, (e advantages of blended teaching, and (f disadvantages of blended teaching. Findings indicated that faculty members were likely to agree that blended teaching provides a high degree of satisfaction and that it requires more time and commitment from the faculty. The faculty members perceived that blended teaching improves student learning and, to some extent, improves motivation. The faculty members also emphasized the importance of institutional support and the use of technology to mitigate student problems. This study presents these faculty members’ perceptions, which are helpful for those planning to implement a blended teaching approach, and makes suggestions for trouble-shooting and taking advantage of the opportunities in a blended environment successfully.

  12. Blend or not to blend: a study investigating faculty members perceptions of blended teaching

    OpenAIRE

    Mehmet A Ocak

    2010-01-01

    This study examined faculty members’ perceptions of blended teaching from several perspectives. A total of 73 faculty members in Turkish Higher Education context participated in the study by completing an online survey that combined quantitative and qualitative approaches. Based on a data analysis, the faculty members’ perceptions were sorted into six categories: (a) satisfaction with blended teaching, (b) perceived impact on the role of the faculty, (c) perceived impact on student learning, ...

  13. Performance of Blended Learning in University Teaching:

    Directory of Open Access Journals (Sweden)

    Michael Reiss

    2010-07-01

    Full Text Available Blended learning as a combination of classroom teaching and e-learning has become a widely represented standard in employee and management development of companies. The exploratory survey “Blended Learning@University” conducted in 2008 investigated the integration of blended learning in higher education. The results of the survey show that the majority of participating academic teachers use blended learning in single courses, but not as a program of study and thus do not exploit the core performance potential of blended learning. According to the study, the main driver of blended learning performance is its embeddedness in higher education. Integrated blended programs of study deliver the best results. In blended learning, learning infrastructure (in terms of software, culture, skills, funding, content providing, etc. does not play the role of a performance driver but serves as an enabler for blended learning.

  14. Coal blending and coal homogenisation facilities

    Energy Technology Data Exchange (ETDEWEB)

    Toerslev Jensen, P. [I/S ELSAM, Fredericia (Denmark)

    1997-12-31

    Blending is becoming increasingly important as a way of improving the quality of coal fired in power plants. This paper gives a basic description of the purposes of coal blending. Although indices for estimating (properties, slagging and fouling propensity, reactivity, etc.) of coal and coal blends exist, these are not considered reliable for coals of widely different origin, and experience will be emphasised as a better tool. The pros and cons of different blending methods are discussed together with the environmental impact of coal blending facilities. Finally, the blending facilities of ELSAM, a power pool serving the western part of Denmark, are described. 7 refs., 5 figs., 4 tabs.

  15. NURBS curve blending using extension

    Institute of Scientific and Technical Information of China (English)

    Yong-jin LIU; Rong-qi QIU; Xiao-hui LIANG

    2009-01-01

    Curve and surface blending is an important operation in CAD systems, in which a non-uniform rational B-spline (NURBS) has been used as the de facto standard. In local comer blending, two curves intersecting at that comer are first made disjoint, and then the third blending curve is added-in to smoothly join the two curves with G1-or G2-continuity. In this paper we present a study to solve the joint problem based on curve extension. The following nice properties of this extension algorithm are exploited in depth: (1) The parameterization of the original shapes does not change; (2) No additional fragments are created.Various examples are presented to demonstrate that our solution is simple and efficient.

  16. Radiation effect on PVC/ENR blends

    International Nuclear Information System (INIS)

    The effect of irradiation on the physical properties of Polyvinyl Chloride / Epoxidised Natural Rubber Blends (PVC/ENR blends) were investigated. The enhancement in tensile strength, elongation at break, hardness and aging properties of the blends have confirmed the positive effect of irradiation on the blends. It is evident from gel fraction and infra red spectroscopic studies that the blends of PVC and ENR cross-linked upon irradiation. The results also revealed that at any blend composition, the enhancement in properties depend on irradiation dose which controls the degree of radiation induced cross-linking. In an attempt to maximize the constructive effect of irradiation, the influence of various additives such as stabilizers, radiation sensitizers, fillers and processing aids on the blend properties were studied. The changes in blend properties upon irradiation with the presents of above additives were also presented in this paper

  17. Production of Silk & Wool Blended Worsted Cloth

    Institute of Scientific and Technical Information of China (English)

    段亚峰; 许琳

    2004-01-01

    Wool & silk blended fancy suiting is desinged. Through trial-production with silk sliver and Australian wool top, the spinning technology is investigated, and the relationship of spinning technology, blending ratio and yam construction is discussed.

  18. NESDIS Blended Rain Rate (RR) Products

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The blended Rain Rate (RR) product is derived from multiple sensors/satellites. The blended products were merged from polar-orbiting and geostationary satellite...

  19. Blended Learning as Transformational Institutional Learning

    Science.gov (United States)

    VanDerLinden, Kim

    2014-01-01

    This chapter reviews institutional approaches to blended learning and the ways in which institutions support faculty in the intentional redesign of courses to produce optimal learning. The chapter positions blended learning as a strategic opportunity to engage in organizational learning.

  20. Performance of Blended Learning in University Teaching:

    OpenAIRE

    Michael Reiss; Dirk Steffens

    2010-01-01

    Blended learning as a combination of classroom teaching and e-learning has become a widely represented standard in employee and management development of companies. The exploratory survey “Blended Learning@University” conducted in 2008 investigated the integration of blended learning in higher education. The results of the survey show that the majority of participating academic teachers use blended learning in single courses, but not as a program of study and thus do not exploit the core perf...

  1. Laboratory optimization of continuous blend asphalt rubber

    OpenAIRE

    Fontes, Liseane P. T. L.; Pereira, Paulo A. A.; Trichês, Glicério; Pais, Jorge C.; Luzia, Rosa

    2008-01-01

    Asphalt rubber from wet process requires batching blending and reaction time associated to blending rubber and conventional asphalt to produce asphalt rubber. The ideal blending of these materials depends on the combination of very important variables, such as the amount of rubber, reaction time and temperature reaction. This paper intends to optimize the laboratory production of asphalt rubber using the continuous blend process. The rubber from waste tyres was reduced by ambient grinding and...

  2. Binary blend nanoparticles with defined morphology

    OpenAIRE

    Ghazy, Omayma

    2008-01-01

    In this study polymer blends of polystyrene and poly(propylene carbonate) were prepared using the miniemulsion process as model systems for the nanoparticles consisting of semiconducting polymers for optical applications. The blends were prepared by mixing nanoparticles of pure polymers or by fabricating blend nanoparticles including both the two polymers in each particle. The development of controlled hemispherical phase separated morphology (Janus morphology) within the blend nanoparticles ...

  3. Towards generating novel games using conceptual blending

    OpenAIRE

    Gow, Jeremy; Corneli, Joseph

    2015-01-01

    We sketch the process of creating a novel video game by blending two video games specified in the Video Game Description Language (VGDL), following the COINVENT computational model of conceptual blending. We highlight the choices that need to be made in this process, and discuss the prospects for a computational game designer based on blending.

  4. 7 CFR 989.16 - Blend.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Blend. 989.16 Section 989.16 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and... CALIFORNIA Order Regulating Handling Definitions § 989.16 Blend. Blend means to mix or commingle raisins....

  5. Netbaserede uddannelser og blended learning

    DEFF Research Database (Denmark)

    Vognsgaard Hjernø, Henriette; Jensen, Michael Peter; Bertelsen, Jesper Vedel

    2016-01-01

    Denne håndbog er tænkt som inspiration til uddannelsesfaglige medarbejdere, som er eller skal i gang med at undervise på en netbaseret uddannelse i UCL. Håndbogen giver et teoretisk overblik i forhold til netbaserede uddannelser, online- og blended learning samt en indførsel i hvilke didaktiske...

  6. Building a Blended Learning Program

    Science.gov (United States)

    McLester, Susan

    2011-01-01

    "Online learning" often serves as an umbrella term that includes the subcategory of blended learning, which might also be referred to as hybrid learning, and comprises some combination of online and face-to-face time. Spurred in part by a 2009 U.S. Department of Education study, "Evaluation of Evidence-Based Practices in Online Learning," which…

  7. SCATTERING FUNCTION OF POLYMER BLENDS

    Institute of Scientific and Technical Information of China (English)

    Lin-ping Ke; Mei-li Guo; De-lu Zhao

    2004-01-01

    For a system of flexible polymer molecules, the concepts of two concentrations, namely the segmental and the molecular concentrations, have been proposed in this paper. The former is equivalent to the volume fraction. The latter can be defined as the number of the gravity centers of macromolecules in a unit volume. The two concentrations should be correlated with each other by the conformational function of the polymer chain and should be discussed in different thermodynamic equations. On the basis of these concepts it has been proved that the Flory-Huggins entropy of mixing should be the result of the mixing "ideal gases of the gravity centers of macromolecules". The general correlation between the free energy of mixing and the scattering function (structural factor) of polymer blends has been studied based on the general fluctuation theory. When the Flory-Huggins free energy of mixing is adopted, the de Gennes scattering function of a polymer blend can be derived.

  8. Confined flow of polymer blends.

    Science.gov (United States)

    Tufano, C; Peters, G W M; Meijer, H E H

    2008-05-01

    The influence of confinement on the steady-state morphology of two different emulsions is investigated. The blends, made from polybutene (PB) in polydimethylsiloxane (PDMS) and polybutadiene (PBD) in PDMS, are sheared between two parallel plates, mostly with a standard gap spacing of 40 microm, in the range of shear rates at which the transition from "bulk" behavior toward "confined" behavior is observed. For both cases, the influence of the concentration was systematically investigated, as well as the shear rate effects on the final steady-state morphology. By decreasing the shear rate, for each blend, the increasing droplets, i.e., increasing confinement for a fixed gap spacing, arrange themselves first into two layers, and when the degree of confinement reaches an even higher value, a single layer of droplets is formed. The ratio between the drop diameters and the gap spacing at which this transition occurs is always lower than 0.5. While decreasing the shear rate, the degree of confinement increases due to drop coalescence. Droplets arrange themselves in superstructures like ordered pearl necklaces and, at the lower shear rates, strings. The aspect ratio and the width of the droplet obtained from optical micrographs are compared to predictions of the single droplet Maffettone-Minale model (MM model(1)). It is found that the theory, meant for unconfined shear flow, is not able to predict the drop deformation when the degree of confinement is above a critical value that depends on the blends considered and the shear rate applied. A recently developed extension of the MM model is reported by Minale (M model(2)) where the effect of the confinement is included by using the Shapira-Haber correction.3 Further extending this M model, by incorporating an effective viscosity as originally proposed by Choi and Showalter,4 we arrive at the mM model that accurately describes the experiments of blends in confined flow. PMID:18348582

  9. Game innovation through conceptual blending

    DEFF Research Database (Denmark)

    Möring, Sebastian Martin

    In  this  paper  I  wish  to  apply implications of  the  Conceptual  Blending  Theory  to  computer  games.  I  will  analyze  chosen  examples  and  discuss  them  as  a  result  of  video  game  innovation  made  possible  through  "conceptual  blending."  Conceptual  blending  links  at  least......  integration  network  consisting  of  at  least  two  input  spaces,  a  generic  space  and  a  blended  space  as  well  as  its  governing  principles  consisting  of  composition,  completion,  and  elaboration.  With  the  help  of  these  instruments  I  analyze computer  games like  Tuper  Tario  Tros.......,  Hell.  The  purpose  of  my  approach  is  not  so  much  to  validate  the  ideas  of  conceptual  blending  theory  through  another  field  of  examples  (computer  games)  but  to  name  and analyze characteristics of the mentioned games with the  help of a given method....

  10. Correspondence Theory and Phonological Blending in French

    Directory of Open Access Journals (Sweden)

    Lee Scott

    2014-07-01

    Full Text Available Though less productive than rival word-formation processes like compounding and affixation, blending is still a rich source of neologisms in French. Despite this productivity, however, blends are often seen by scholars as unpredictable, uninteresting, or both. This analysis picks up where recent studies of blending have left off, using Correspondence Theory and a bundle of segmental constraints to deal with this phenomenon as it pertains to French. More specifically, it shows that blending is the result of a single output standing in correspondence with two or more other outputs, and that we do not need to refer to prosodic information, which is crucial in accounts of blending in languages with lexical stress like English, to account for the process in French. The analysis also differs from previous studies in that it locates blending exclusively within the phonology, leaving its morphological and semantic characteristics to be handled by other processes in the grammar.

  11. Miscibility evolution of polycarbonate/polystyrene blends during compounding

    DEFF Research Database (Denmark)

    Chuai, Chengzhi; Almdal, Kristoffer; Johannsen, Ib;

    2002-01-01

    The miscibility evolution of polycarbonate/polystyrene (PC/PS) blends during the compounding process in three blending methods of industrial relevance, namely melt blending, remelt blending in a twin-screw extruder and third melt blending in an injection molding machine, was investigated by...

  12. Morphology Evolution of Polycarbonate-Polystyrene Blends During Compounding

    DEFF Research Database (Denmark)

    Chuai, Chengzhi; Almdal, Kristoffer; Johannsen, Ib;

    2001-01-01

    The morphology evolution of polycarbonate-polystyrene (PC/PS) blends during the compounding process in three blending methods of industrial relevance, namely melt blending, re-melt blending in a twin-screw extruder and tri-melt blending in an injection-moulding machine, was investigated using...

  13. A Time Based Blended Learning Model

    OpenAIRE

    Norberg, Anders; Dziuban, Charles D; Moskal, Patsy M

    2011-01-01

    Purpose – This paper seeks to outline a time-based strategy for blended learning that illustrates course design and delivery by framing students' learning opportunities in synchronous and asynchronous modalities. Design/methodology/approach – This paper deconstructs the evolving components of blended learning in order to identify changes induced by digital technologies for enhancing teaching and learning environments. Findings – This paper hypothesizes that blended learning may be traced back...

  14. Constructivism Based Blended Learning in Higher Education

    OpenAIRE

    Ahmad Mhammad Al-Huneidi; Jeanne Schreurs

    2012-01-01

    This paper explain how to apply Constructivism and Conversation theories in Blended Learning environment in order to increase learning outcomes and quality. Some scenarios of Constructivism based blended learning activities are presented in this paper. In addition, a Constructivism Based Blended Learning model for “ICT Management†course, a compulsory course in Master of Management Information Systems program at Hasselt University, is proposed. The proposed model applies and combines Const...

  15. Evaporation characteristics of ETBE-blended gasoline

    International Nuclear Information System (INIS)

    Highlights: • We chose 8-component hydrocarbon mixture as a model gasoline, and defined the molar mass of gasoline. • We proposed an evaporation model assuming a 2-component mixture of gasoline and ETBE. • We predicted the change in the vapor pressure of ETBE-blended gasoline by evaporation. • The vapor pressures were measured and compared as a means of verifying the model. • We presented the method for predicting flash points of the ETBE-blended gasoline. - Abstract: To reduce greenhouse gas emissions, which contribute to global warming, production of gasoline blended with ethyl tert-buthyl ether (ETBE) is increasing annually. The flash point of ETBE is higher than that of gasoline, and blending ETBE into gasoline will change the flash point and the vapor pressure. Therefore, it is expected that the fire hazard caused by ETBE-blended gasoline would differ from that caused by normal gasoline. The aim of this study was to acquire the knowledge required for estimating the fire hazard of ETBE-blended gasoline. Supposing that ETBE-blended gasoline was a two-component mixture of gasoline and ETBE, we developed a prediction model that describes the vapor pressure and flash point of ETBE-blended gasoline in an arbitrary ETBE blending ratio. We chose 8-component hydrocarbon mixture as a model gasoline, and defined the relation between molar mass of gasoline and mass loss fraction. We measured the changes in the vapor pressure and flash point of gasoline by blending ETBE and evaporation, and compared the predicted values with the measured values in order to verify the prediction model. The calculated values of vapor pressures and flash points corresponded well to the measured values. Thus, we confirmed that the change in the evaporation characteristics of ETBE-blended gasoline by evaporation could be predicted by the proposed model. Furthermore, the vapor pressure constants of ETBE-blended gasoline were obtained by the model, and then the distillation curves were

  16. Learning to Blend Computer Game Levels

    OpenAIRE

    Guzdial, Matthew; Riedl, Mark

    2016-01-01

    We present an approach to generate novel computer game levels that blend different game concepts in an unsupervised fashion. Our primary contribution is an analogical reasoning process to construct blends between level design models learned from gameplay videos. The models represent probabilistic relationships between elements in the game. An analogical reasoning process maps features between two models to produce blended models that can then generate new level chunks. As a proof-of-concept w...

  17. Rheological properties of olefinic thermoplastic elastomer blends

    OpenAIRE

    Sengers, W.G.F.

    2005-01-01

    Thermoplastic Elastomers (TPE) are a class of materials that have rubber-like properties and can be processed like thermoplastic polymers. In this thesis, the rheological properties of two TPE blends are correlated to their morphology. The thermoplastic vulcanisates (TPV) consist of micron-sized, cured elastomer particles while the blends of PP and the triblock copolymer SEBS show co-continuous structures. Both blends also contain considerable amount of paraffinic oil. The difference between ...

  18. Structuring of Interface-Modified Polymer Blends

    DEFF Research Database (Denmark)

    Lyngaae-Jørgensen, Jørgen

    1999-01-01

    The paper treats the case where blends of polystyrene (PS), poly (dimethylsiloxane) (PDMS) and a diblock copolymer of PS and PDMS are used as model materials. This modelsystem is predicted to be "stable" in discrete blends in simple shear flow. Stable in the sence that the block copolymer can not...... inversion volume predicted by theory is outside the observed IPS interval for one of the investigated blend pairs....

  19. ASP, Amalgamation and the Conceptual Blending Workflow

    OpenAIRE

    Eppe, Manfred; Maclean, Ewen; Confalonieri, Roberto; Kutz, Oliver; Schorlemmer, Marco; Plaza, Enric

    2015-01-01

    We present an amalgamation technique used for conceptual blending – a concept invention method that is advocated in cognitive science as a fundamental, and uniquely human engine for creative thinking. Herein, we employ the search capabilities of ASP to find commonalities among input concepts as part of the blending process, and we show how our approach fits within a generalised conceptual blending workflow. Specifically, we orchestrate ASP with imperative programming languages like Python, to...

  20. THE COMBUSTION CHARACTERISTICS OF LIGNITE BLENDS

    Institute of Scientific and Technical Information of China (English)

    Cheng Jun; Zhou Junhu; Cao Xinyu; Cen Kefa

    2000-01-01

    The combustion characteristics of lignite blends were studied with a thermogravimetric analyzer (t.g.a.), at constant heating rate.The characteristic temperatures were determined from the burning profiles.It was found that the characteristic times of combustion reaction moved forward, the ignition temperature dropped and the burnout efficiency slightly changed when blending lignites.The characteristic parameters of blends could not be predicted as a linear function of the average values of the individual lignites.when blending with less reactive coal, the ignition and burnout characteristics of lignite turned worse.

  1. Sludge Stabilization Campaign blend plan

    International Nuclear Information System (INIS)

    This sludge stabilization blend plan documents the material to be processed and the order of processing for the FY95 Sludge Stabilization Campaign. The primary mission of this process is to reduce the inventory of unstable plutonium bearing sludge. The source of the sludge is residual and glovebox floor sweepings from the production of material at the Plutonium Finishing Plant (PFP). The reactive sludge is currently being stored in various gloveboxes at PFP. There are two types of the plutonium bearing material that will be thermally stabilized in the muffle furnace: Plutonium Reclamation Facility (PRF) sludge and Remote Mechanical C (RMC) Line material

  2. Sludge Stabilization Campaign blend plan

    Energy Technology Data Exchange (ETDEWEB)

    De Vries, M.L.

    1994-10-04

    This sludge stabilization blend plan documents the material to be processed and the order of processing for the FY95 Sludge Stabilization Campaign. The primary mission of this process is to reduce the inventory of unstable plutonium bearing sludge. The source of the sludge is residual and glovebox floor sweepings from the production of material at the Plutonium Finishing Plant (PFP). The reactive sludge is currently being stored in various gloveboxes at PFP. There are two types of the plutonium bearing material that will be thermally stabilized in the muffle furnace: Plutonium Reclamation Facility (PRF) sludge and Remote Mechanical C (RMC) Line material.

  3. STUDENTS’ OPINIONS ON BLENDED LEARNING

    OpenAIRE

    BALCI, Meric; SORAN, HALUK

    2009-01-01

    E-learning was acknowledged by most educators and researchers as a savior, even an only alternative in education field, especially in the following years of its emergence. However, with the rise of its limitations, the idea of bringing face-to-face learning and e-learning together to complete each other has occured. Blended learning is a method emerged as a result of this sentiment. The new education alternatives which have been discovered as a consequence of the researches and the studies ma...

  4. Custom blending of lamp phosphors

    Science.gov (United States)

    Klemm, R. E.

    1978-01-01

    Spectral output of fluorescent lamps can be precisely adjusted by using computer-assisted analysis for custom blending lamp phosphors. With technique, spectrum of main bank of lamps is measured and stored in computer memory along with emission characteristics of commonly available phosphors. Computer then calculates ratio of green and blue intensities for each phosphor according to manufacturer's specifications and plots them as coordinates on graph. Same ratios are calculated for measured spectrum. Once proper mix is determined, it is applied as coating to fluorescent tubing.

  5. A Review on Conceptual Blending Theory

    Institute of Scientific and Technical Information of China (English)

    刘丽

    2010-01-01

    The CBT(Conceptual Blending Theory)is rapidly emerging as a major force in cognitive science and provides a unifying umbrella framework for a range of cognitive phenomena.The present paper is to have a general review of the conceptual blending theory through illustrating its four-space theory in order to have a better comprehension of its nature.

  6. Introducing blended e-learning course design

    DEFF Research Database (Denmark)

    Gyamfi, Samuel Adu; Ryberg, Thomas

    2012-01-01

    In the face of diminishing education budgets in higher education, blended learning has been found to be a viable and effective approach to deliver high-quality, up-to-date, on-demand solutions to developing cross-curricular skills of undergraduates. However, research has also shown that blended l...

  7. PAIRWISE BLENDING OF HIGH LEVEL WASTE

    International Nuclear Information System (INIS)

    The primary objective of this study is to demonstrate a mission scenario that uses pairwise and incidental blending of high level waste (HLW) to reduce the total mass of HLW glass. Secondary objectives include understanding how recent refinements to the tank waste inventory and solubility assumptions affect the mass of HLW glass and how logistical constraints may affect the efficacy of HLW blending

  8. Dynamic Heterogeneity in Interacting Miscible Polymer Blends

    Science.gov (United States)

    Gaikwad, Ashish; Lodge, Timothy

    2008-03-01

    Dynamic heterogeneity leading to time-temperature superposition (tTS) failure has been widely reported in non-interacting/weakly interacting miscible polymer blends. However, coupling of the component dynamic response in blends, even with a huge dynamic asymmetry in the pure components, is possible with H-bonding interactions. This study is focused on finding the minimum level of interaction necessary for thermo-rheological simplicity in blends. Blends of styrene-co-vinylphenol (PSVPh) and poly(vinyl methyl ether) (PVME) were chosen. Incorporation of styrene provides an effective way to modulate H-bonding interactions in the system. Linear viscoelastic data indicate that tTS fails for PS/PVME blends, whereas data obtained for different PVPh/PVME blends showed that tTS was obeyed a over wide temperature range. For PSVPh/PVME blends with low PSVPh content, tTS was successful. This suggests that the presence of alternating styrene and vinyl phenol units was insufficient for dynamic response decoupling. Further studies are in progress, with varying vinyl phenol content in PSVPh, to explore the influence of H-bonding on dynamic heterogeneity and blend dynamics.

  9. Preparing Teachers for Emerging Blended Learning Environments

    Science.gov (United States)

    Oliver, Kevin M.; Stallings, Dallas T.

    2014-01-01

    Blended learning environments that merge learning strategies, resources, and modes have been implemented in higher education settings for nearly two decades, and research has identified many positive effects. More recently, K-12 traditional and charter schools have begun to experiment with blended learning, but to date, research on the effects of…

  10. Perspectives on Blended Learning in Higher Education

    Science.gov (United States)

    Vaughan, N.

    2007-01-01

    This article explores the benefits and challenges of blended learning in higher education from the perspective of students, faculty, and administration that have had direct experience with this form of course delivery. Students indicate that a blended learning model provides them with greater time flexibility and improved learning outcomes but…

  11. Green emitting phosphors and blends thereof

    Science.gov (United States)

    Setlur, Anant Achyut; Siclovan, Oltea Puica; Nammalwar, Prasanth Kumar; Sathyanarayan, Ramesh Rao; Porob, Digamber G.; Chandran, Ramachandran Gopi; Heward, William Jordan; Radkov, Emil Vergilov; Briel, Linda Jane Valyou

    2010-12-28

    Phosphor compositions, blends thereof and light emitting devices including white light emitting LED based devices, and backlights, based on such phosphor compositions. The devices include a light source and a phosphor material as described. Also disclosed are phosphor blends including such a phosphor and devices made therefrom.

  12. PAIRWISE BLENDING OF HIGH LEVEL WASTE (HLW)

    Energy Technology Data Exchange (ETDEWEB)

    CERTA, P.J.

    2006-02-22

    The primary objective of this study is to demonstrate a mission scenario that uses pairwise and incidental blending of high level waste (HLW) to reduce the total mass of HLW glass. Secondary objectives include understanding how recent refinements to the tank waste inventory and solubility assumptions affect the mass of HLW glass and how logistical constraints may affect the efficacy of HLW blending.

  13. Study on combustion characteristics of blended coals

    Institute of Scientific and Technical Information of China (English)

    LI Yonghua; WANG Chunbo; CHEN Hongwei

    2007-01-01

    Power plants in China have to burn blended coal instead of one specific coal for a variety of reasons.So it is of great necessity to investigate the combustion of blended coals.Using a test rig with a capacity of 640 MJ/h with an absolute milling system and flue gas online analysis system,characteristics such as burnout,slag,and pollution of some blended coals were investigated.The ratio of coke and slag as a method of distinguishing coal slagging characteristic was introduced.The results show that the blending of coal has some effect on NOx but there is no obvious rule.SOx emission can be reduced by blending low sulfur coal.

  14. THE EFFECT OF BLENDING SEQUENCE ON PHASE MORPHOLOGY OF NYLON 6/ABS/SMA BLENDS

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The preparation process-dependent phase morphology of blends composed of nylon 6 and acryionitrile-butadienestyrene(ABS)over a composition range of 30-70 wt% using a styrene-maleic anhydride(SMA)copolymer as the compatibilizing agent with a constant content(5phr)was investigated.The results of the scanning electron microscope (SEM)observation revealed that compared with the binary blends of nylon 6 and ABS,the existence of SMA caused a composition shift of phase inversion to a higher weight fraction of nylon 6 when ABS was blended with the preblended nylon 6/SMA blend,while the co-continuous structures could be observed over a considerably narrower composition range when nylon 6 was blended with the pre-blended ABS/SMA blend.An examination through dynamic mechanical analysis (DMA)tests confirmed the results obtained with SEM.It is found that near the phase inversion region a remarkable change in the dynamic storage modulus(G')and the loss tangent(tanδ)appears.Moreover,the influence of blending sequence on the size of dispersed particles has been probed for uncompatibilized and compatibilized blends of nylon 6 and ABS over a wide range of compositions below or beyond the phase inversion points.For the blends of ABS dispersed in a nylon 6 matrix,little discernible effects of blending sequence on particle size could be observed.Furthermore,there exists a significant difference in morphologies of the blends prepared by nylon 6 particles dispersing in a ABS matrix in cases of different blending sequences used.Some possible factors responsible for the above asymmetric behaviors have been proposed.

  15. Imaging Microlens Blends Using Image Subtraction

    CERN Document Server

    Gould, A; Gould, Andrew; An, Jin H.

    2002-01-01

    Blended light is an important source of degeneracy in the characterization of microlensing events, particularly in binary-lens and high magnification events. We show how the techniques of image subtraction can be applied to form an image of the blend with the source removed. In many cases, it should be possible to construct images with very high signal-to-noise ratio. Analysis of these images can help distinguish between competing models that have different blend fractions, and in some cases should allow direct detection of the lens.

  16. Segmentation and Representation of Consonant Blends in Kindergarten Children's Spellings

    Science.gov (United States)

    Werfel, Krystal L.; Schuele, C. Melanie

    2012-01-01

    Purpose: The purpose of this study was to describe the growth of children's segmentation and representation of consonant blends in the kindergarten year and to evaluate the extent to which linguistic features influence segmentation and representation of consonant blends. Specifically, the roles of word position (initial blends, final blends),…

  17. Blended Learning-A Focus Study on Asia

    OpenAIRE

    Kwong Onn Tham; ChoiKit Tham

    2011-01-01

    Blended learning is gaining popularity in Asia. This paper examines the current stage of development of blended learning in higher education in China, Korea, Japan, and Singapore and the challenges encountered. While blended learning is well-received in western culture, it has met with varying degrees of success in Asia due in part to the different perceptions of instructors and students towards blended learning approaches. In China, for example, while blended learning was well-received, the ...

  18. Prospects of Blended Learning Implementation at Technical University

    OpenAIRE

    Buran, Anna Leonidovna; Evseeva, Arina Mikhailovna

    2015-01-01

    The present paper explores the integration of a blended learning course in the process of learning English as a second language at the technical university. We overview the difference between traditional, web facilitated, blended learning and online course; the implementation of the blended learning course in the process of learning English at the technical university. The article also investigates the benefits and drawbacks of blended learning and the possibilities of a blended learning cour...

  19. Monitoring Blending of Pharmaceutical Powders with Multipoint NIR Spectroscopy

    OpenAIRE

    SCHEIBELHOFER, OTTO; Balak, Nikolaus; Wahl, Patrick R.; Koller, Daniel M.; Glasser, Benjamin J; Khinast, Johannes G.

    2012-01-01

    Blending of powders is a crucial step in the production of pharmaceutical solid dosage forms. The active pharmaceutical ingredient (API) is often a powder that is blended with other powders (excipients) in order to produce tablets. The blending efficiency is influenced by several external factors, such as the desired degree of homogeneity and the required blending time, which mainly depend on the properties of the blended materials and on the geometry of the blender. This experimental study i...

  20. Enzymatic degradation of polycaprolactone-gelatin blend

    Science.gov (United States)

    Banerjee, Aditi; Chatterjee, Kaushik; Madras, Giridhar

    2015-04-01

    Blends of polycaprolactone (PCL), a synthetic polymer and gelatin, natural polymer offer a optimal combination of strength, water wettability and cytocompatibility for use as a resorbable biomaterial. The enzymatic degradation of PCL, gelatin and PCL-gelatin blended films was studied in the presence of lipase (Novozym 435, immobilized) and lysozyme. Novozym 435 degraded the PCL films whereas lysozyme degraded the gelatin. Though Novozym 435 and lysozyme individually could degrade PCL-gelatin blended films, the combination of these enzymes showed the highest degradation of these blended films. Moreover, the enzymatic degradation was much faster when fresh enzymes were added at regular intervals. The changes in physico-chemical properties of polymer films due to degradation were studied by scanning electron microscopy, Fourier transform infrared spectroscopy and differential scanning calorimetry. These results have important implications for designing resorbable biomedical implants.

  1. Blending Parametric Patches with Subdivision Surfaces

    Institute of Scientific and Technical Information of China (English)

    李桂清; 李华

    2002-01-01

    In this paper the problem of blending parametric surfaces using subdivision patches is discussed. A new approach, named removing-boundary, is presented to generate piecewise-smooth subdivision surfaces through discarding the outmost quadrilaterals of the open meshes derived by each subdivision step. Then the approach is employed both to blend parametric bicubic B-spline surfaces and to fill n-sided holes. It is easy to produce piecewisesmooth subdivision surfaces with both convex and concave corners on the boundary, and limit surfaces are guaranteed to be C2 continuous on the boundaries except for a few singular points by the removing-boundary approach. Thus the blending method is very efficient and the blending surface generated is of good effect.

  2. 27 CFR 24.198 - Blending.

    Science.gov (United States)

    2010-04-01

    ... the production of special natural wine of the same type, e.g., producing a sweet vermouth by blending sweet vermouths produced under two or more approved formulas, the submission and approval of...

  3. NESDIS Blended Total Precipitable Water (TPW) Products

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The blended Total Precipitable Water (TPW) product is derived from multiple sensors/satellites. The Percentage of TPW normal (PCT), or TPW anomaly, shows the...

  4. Constructivism Based Blended Learning in Higher Education

    OpenAIRE

    Al-Huneidi, Ahmad

    2011-01-01

    Blended Learning, which is a mix of online and face-to-face learning, can combine the benefits of both, traditional classroom learning and e-learning environments.3 The aim of this thesis is to explore how to design and implement Blended Learning environment based on Constructivism theory, which focuses on students’ experience to construct the knowledge, in order to increase learning outcomes, performance, and quality in academic institutions. An affective and successful learni...

  5. Blending of polyethylene materials for pipe applications

    OpenAIRE

    Wright, Wayne Clifton Augustus

    1989-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. Melt blending of polyethylene, in particularly HDPE and LLDPE, have been shown to be a major success, especially in the film markets. In this thesis studies are reported on the stress rupture performance of pipes produced from selected polyethylene materials blended to a chosen MDPE pipe grade. The pipes were tested, notched or unnotched, at a single temperature of 80oC and at internal pressu...

  6. Blended learning approaches enhance student academic performance

    OpenAIRE

    Morris, NP

    2010-01-01

    Blended learning, or technology enhanced learning, is increasingly becoming an expectation for higher education students. Blended learning allows for the enhancement of face-to-face interaction between tutors and students, using internet or computer based tools. In this paper, a range of case studies are described which illustrate methods to engage students with technology enhanced learning and improve academic performance and student satisfaction. In the first case study, first year undergra...

  7. Redesigning A Course For Blended Learning Environment

    OpenAIRE

    Orhan, Feza

    2008-01-01

    ABSTRACT This article describes a collaborative study of the blended learning approach, designed to pave the way for higher education students to integrate online and face-to-face learning environments in an “Instructional Technology and Material Development” course at the University of Yildiz Technic in Turkey. The purpose of this study is to investigate the students’ perceptions of the blended learning environment and to trace the integration between online and face-to-face learning environ...

  8. Surface segregation of conformationally asymmetric polymer blends

    OpenAIRE

    Stepanow, Semjon; Fedorenko, Andrei A.

    2005-01-01

    We have generalized the Edwards' method of collective description of dense polymer systems in terms of effective potentials to polymer blends in the presence of a surface. With this method we have studied conformationally asymmetric athermic polymer blends in the presence of a hard wall to the first order in effective potentials. For polymers with the same gyration radius $R_g$ but different statistical segment lengths $l_{A}$ and $l_{B}$ the excess concentration of stiffer polymers at the su...

  9. Physical Aging of Miscible Polymer Blends

    OpenAIRE

    Robertson, Christopher

    1999-01-01

    Physical aging measurements were performed on various polymeric glasses with the overriding goal of developing a better molecular picture of the nonequilibrium glassy state. To this end, aging-induced changes in mechanical properties and in the thermodynamic state (volume and enthalpy) were assessed for two different miscible polymer blends as a function of both composition and aging temperature. This investigation considered the physical aging behavior of blends containing atactic polystyr...

  10. Interfacial Slip in Sheared Polymer Blends

    OpenAIRE

    Lo, Tak Shing; Mihajlovic, Maja; Shnidman, Yitzhak; Li, Wentao; Gersappe, Dilip

    2004-01-01

    We have developed a dynamic self-consistent field theory, without any adjustable parameters, for unentangled polymer blends under shear. Our model accounts for the interaction between polymers, and enables one to compute the evolution of the local rheology, microstructure and the conformations of the polymer chains under shear self-consistently. We use this model to study the interfacial dynamics in sheared polymer blends and make a quantitative comparison between this model and Molecular Dyn...

  11. Blended Interaction Spaces for Collaborative Design

    DEFF Research Database (Denmark)

    Dalsgaard, Peter; Halskov, Kim; Klokmose, Clemens Nylandsted

    During the past five years, we have explored the use, potentials and challenges of Blended Interaction spaces. In addition, we have a long background in developing and exploring methods for collaborative design. In this workshop paper, we give an overview of our work and present our visions and...... ongoing research in developing Blended Interaction spaces for collaborative design. We then identify key themes and challenges pertinent for the workshop....

  12. Blended Learning in International Nuclear Education

    International Nuclear Information System (INIS)

    The spread of nuclear power ambitions beyond the few early-adopter nations requires more globalized education. Two of the learning problems specific to international education are the need for a common instructional language and different cultural styles of learning. Blended learning, a mix of personal interaction between teacher and impersonal computer-based learning, can solve these problems. The new KEPCO International Nuclear Graduate School outside Ulsan, Korea is investing heavily in blended learning

  13. The water permeability of blended polyethylene films

    OpenAIRE

    Wong, ACY

    1995-01-01

    Water vapour transmission (WVT) characteristics of blended polyethylene films blown from a 45 mm single-screw extruder were examined. For a given die gap size and blow-up ratio, it was found that WVT basically had an exponential decaying relationship with increasing film thickness. For a given film thickness, molecular orientation on the film in the machine direction could be increased by increasing the size of the die gap. It was found that WVT of blended polyethylene films which involved so...

  14. Film formation from latex blends

    Science.gov (United States)

    Tang, Jiansheng

    2000-10-01

    Film formation from hard/soft (i.e., high Tg/low Tg) latex blends consisting of hard polystyrene (PS) and soft poly(n-butyl methacrylate-co-n-butyl acrylate) [P(BMA/BA)] latex particles were studied with an emphasis on the influence of the carboxyl groups present on the latex particles. A theoretical model was developed to calculate the optimal surfactant and monomer feed rates for a semicontinuous polymerization process to synthesize monodisperse carboxylated latex particles and independently control the particle size and degree of carboxylation. An important finding obtained from the drying studies is that the drying rate from the edge zone is much faster than the rate obtained from the latex pool. It was also found that the presence of carboxyl groups on the latex particles retarded the drying rate. Utilizing PS particles with a low density of carboxyl groups present on the particle surfaces (e.g., 10% surface coverage) resulted in an even distribution of these particles in the soft copolymer matrix, and thus, good film gloss was achieved. However, the use of hard particles with a high density of carboxyl groups present (e.g., 65% coverage) resulted in a less even distribution of PS particles and poor gloss. A cluster model and a hydrogen bonding mechanism were proposed to explain these phenomena. The presence of the carboxyl groups on the PS particles significantly enhanced the Young's modulus and the yield strength, but did not influence the ultimate mechanical properties. A quantitative model was proposed to predict the Young's modus of the latex blend films as a function of the carboxyl group coverage on the hard particles. There was a good fit between model and the experimental data. The stability of the precipitated calcium carbonate (PCC) particles in the P(BMA/BA) latexes was determined by the charge on pigment surface which, in turn, was influenced by the presence of sodium polyacrylate stabilizer. It was found that the wetting ability of the soft

  15. WI Biodiesel Blending Progream Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Redmond, Maria E; Levy, Megan M

    2013-04-01

    The Wisconsin State Energy Office's (SEO) primary mission is to implement cost effective, reliable, balanced, and environmentally friendly clean energy projects. To support this mission the Wisconsin Biodiesel Blending Program was created to financially support the installation infrastructure necessary to directly sustain biodiesel blending and distribution at petroleum terminal facilities throughout Wisconsin. The SEO secured a federal directed award of $600,000 over 2.25 years. With these funds, the SEO supported the construction of inline biodiesel blending facilities at two petroleum terminals in Wisconsin. The Federal funding provided through the state provided a little less than half of the necessary investment to construct the terminals, with the balance put forth by the partners. Wisconsin is now home to two new biodiesel blending terminals. Fusion Renewables on Jones Island (in the City of Milwaukee) will offer a B100 blend to both bulk and retail customers. CITGO is currently providing a B5 blend to all customers at their Granville, WI terminal north of the City of Milwaukee.

  16. Microstructural blending of coal to enhance flowability

    Energy Technology Data Exchange (ETDEWEB)

    Abou-Chakra, H.; Tuezuen, U. [Surrey Univ., Guildford (United Kingdom). Dept. of Chemical and Process Engineering

    2000-09-11

    Coal-fired power stations for electricity generation are well known to suffer from chronic problems in coal handling and flow affecting the operation of pulverisation mills and combustors. The economic impact of coal handling facilities can be significant, resulting in total shutdown of the power generating plant in some extreme cases. In coal-fired power generation, optimal operation of the combustors requires the ash content of pulverised coal not exceed 20%. Excessive ash content would result in lower calorific value. Therefore, the overall profitability of the market coal tends to be strongly effected by the ash content of the raw coal. However, the flowability of coal tends to be strongly affected by the moisture content of the constituent particles, as well as the presence of high fines fraction. The experimental work described in this paper aims to illustrate how flowability can be enhanced by optimising particle size distribution and particle surface moisture in blends of raw and washed coals. The results of the flowability tests obtained with ''microstructurally'' blended samples indicate that to ensure flowability in process vessels, it is necessary to blend according to important microstructural criteria as well as minimising ash content. Microstructural blending is not included in current industrial practice, which only blends washed and raw coals to produce high calorific value and low ash content. The work presented here establishes methodology for microstructural blending to enhance bulk flowability. (orig.)

  17. Polymer dynamics in binary blends

    Science.gov (United States)

    Wilson, Jeffrey D.; Loring, Roger F.

    1992-09-01

    We develop a theory of the dynamics of flexible linear polymers in a melt composed of macromolecules of two molecular weights and of the same chemical species. A polymer is represented by a freely jointed chain that moves by two dynamical processes. The first is a local jump motion that may be blocked by obstacles, and the second is a slithering mode that mimics reptation. The dynamics of the obstacles are determined self-consistently by an ansatz that associates their relaxation with the dynamics of the slowest mode of conformational relaxation of a chain. The calculations of the autocorrelation function of the end-to-end vector and of the mean squared displacement of the center of mass are related exactly to the solution of a random walk problem with dynamical disorder. We calculate the necessary random walk propagator by applying the dynamical effective medium approximation. Calculations of the dependence of the self-diffusion coefficient of both components on blend composition and on molecular weights are presented. The theory is shown to provide a unified description of diffusion in the unentangled and entangled regimes.

  18. Sulfur meter speeds coal blending

    International Nuclear Information System (INIS)

    The sulfur content has become the most important criterion that industry looks at when purchasing coal. The exact amount of sulfur in coal being processed by a preparation plant must be known and, if possible, controlled by blending coal streams of various sulfur contents. Present techniques, however, of measuring the sulfur in coal involve laborious and time-consuming sampling and chemical analysis (12 to 24 hr), and the results usually are not available until the following day. By then, the coal barges or trains are already on the way to their destinations. A new nuclear sulfur meter is expected to overcome these difficulties and help lead to true automation in coal preparation plants. Initially developed by the Bureau of Mines' Morgantown Energy Research Center (MERC) at Morgantown, W. Va., and completed after reorganization of the center by the US Energy Research and Development Administration (ERDA), the meter can scan coal to produce a reading within 2 min to an accuracy of 0.04 percent sulfur. The meter is expected to soon result in an element-ash-moisture-Btu meter that would rapidly detect the sulfur, sodium, potassium, and overall mineral content of the coal, as well as its ash and Btu content

  19. Blended Learning: How Teachers Balance the Blend of Online and Classroom Components

    Science.gov (United States)

    Jeffrey, Lynn M.; Milne, John; Suddaby, Gordon

    2014-01-01

    Despite teacher resistance to the use of technology in education, blended learning has increased rapidly, driven by evidence of its advantages over either online or classroom teaching alone. However, blended learning courses still fail to maximize the benefits this format offers. Much research has been conducted on various aspects of this problem,…

  20. Binary blend Nanoparticles with defined morphology

    International Nuclear Information System (INIS)

    The word blend in linguistics means a word formed from two parts of two words. In polymer science polymer blends means polymer mixtures, a class of materials analogues to the metal alloys. Blending of polymers is a simple and economic way to create new materials meeting specific desired properties. The other alternative is to synthesize such materials eventually facing the organic chemistry design difficulties. The low entropy of mixing polymers makes the process thermodynamically unfavorable, unless there are some specific interactions between the mixed polymers. As a result, in thermal equilibrium typically a phase separation between the blend components takes place. The main challenge facing the blending of polymers is the control of the length scale of the phase separation. One of the most important applications, where the control of the phase separation is crucial for the performance is the organic solar cells. In organic solar cells a blend of an electron donating polymer and electron accepting one is formed. The dimensions of the phase separation between the two polymers should be in the range of the exciton diffusion length [1-3] (in semiconductors, exciton diffusion length is the average distance traveled by the electron-hole pair before recombination). Only under this condition the charge transfer at the interface between the two polymer layers can take place and the solar cell performs efficiently. The thin polymer blend layers for such applications are commonly deposited by spin coating from solution containing both polymers. The morphology of the thin layer prepared in this way is highly influenced by the preparation conditions such as the surface properties of the substrate, the solvent from which the blend was deposited, the temperature, and the annealing temperature [4-9]. Therefore controlling the length scale of phase separation in layers casted or spin coated from solutions is difficult and is a matter of trials and errors. Recently a novel

  1. Radiochemical compatibility of EPDM/PP blends

    International Nuclear Information System (INIS)

    The capacity of ethylene-propylene-diene terpolymer to be cross-linked by its exposure to high energy radiation was considered in this work. γ-irradiation of EPDM/PP (ethylene-propylene-diene terpolymer/polypropylene) blends proved that free radicals provided by PP can be grafted on the EPDM backbone. Gel content measurements over all blending concentrations revealed a maximum level cross-linking at around 200 kGy. Simultaneity of cross-linking and oxidative degradation in irradiated polymers requires the choice of proper conditions to obtain high durability. IR spectroscopic measurements of carbonyl and hydroxyl indexes emphasize that low concentrations in radiolytic products is attained at short exposure (less than 200 kGy). This work presents the difference between raw and degraded polypropylene used for mixture preparation. The radiochemical behaviour of similar compositions of blends is proved. Thermal stability of non-irradiated EPDM/PP blend was checked by oxygen uptake method that confirms the higher probability of polypropylene to provide free radicals in a large extent. The high temperature used in the oxidation testing of present blends requires radiochemical compatibility of polymers. (authors)

  2. HIGH SCHOOL STUDENTS’ VIEWS ON BLENDED LEARNING

    Directory of Open Access Journals (Sweden)

    Ibrahim Umit YAPICI,

    2012-08-01

    Full Text Available In this study, it is aimed to determine the high school students’ views on blended learning. The study was carried out in biology course for the lesson unit of “Classification of Living Things and Biodiversity” with 47 9th grade students attending Nevzat Ayaz Anatolian High School in the second term of the academic year of 2009-2010. The lessons were taught in a way appropriate to the blended learning model both via the Internet and on face-to-face basis. As the online dimension of the blended learning model, Moodle, a Learning Management System (LMS, was used. The application lasted 10 weeks. The scale of learners’ views on blended learning was applied and interviews were held to determine the views. As a result of the analysis of the scale, it was seen that their views were “highly” positive. The interviews held with the students revealed that the blended learning model provided students with various opportunities such as getting prepared for the lessons, reviewing the lessons as many times as wanted, reaching the subject-related materials without being dependent on time and place, testing oneself and communicating with the teacher and other students out of the school. The interviews also revealed that there were various problems though such as lack of Internet connection at home and problems experienced while playing the videos.

  3. Learning Design Development for Blended Learning

    DEFF Research Database (Denmark)

    Hansen, Janne Saltoft

    Learning design development for blended learning We started implementing Blackboard at Aarhus University in 2013. At the Health Faculty Blackboard replaced AULA which was a LMS with functionality for file distribution and only a vague focus on learning tools. Most teachers therefore had no...... experiences with blended leaning and technology supported out-of-class activities. At the pedagogical unit at the Health faculty we wanted to follow the Blackboard implementation with pedagogical tools for learning design to evolve the pedagogical use of the system. We needed to make development of blended...... learning courses easier for the teachers and also ensure quality in the courses. This poster describes the process from development of the learning design to implementation of the learning design at the faculty: 1. How to place demands on a learning design-model and how to develop and use such a model. 2...

  4. Controlled morphology of biodegradable polymer blends

    Science.gov (United States)

    Buddhiranon, Sasiwimon; Kyu, Thein

    2009-03-01

    Phase diagrams of biodegradable polymer blends containing poly(ɛ-caprolactone) (PCL) and poly(d,l-lactic acid) (PDLLA) having two different molecular weights were established by means of cloud point measurement and differential scanning calorimetry. Subsequently, the theoretical phase diagram was calculated self-consistently based on the combination of Flory-Huggins free energy for liquid-liquid phase separation and phase field free energy for crystal solidification. The phase diagrams thus obtained were LCST type or hour-glass type, which depended on molecular weight of PDLLA utilized. Guided by the phase diagram, the emerged morphology was determined as a function of blend concentration and temperature. It appears that the morphology control is feasible that ultimately affects the end-use property of PCL/PDLLA blends. A wide variety of morphology of biodegradable polymer may be developed with the porous structure and pore size to control scaffold porosity and the rate of drug delivery.

  5. Designed blending for near infrared calibration.

    Science.gov (United States)

    Scheibelhofer, Otto; Grabner, Bianca; Bondi, Robert W; Igne, Benoît; Sacher, Stephan; Khinast, Johannes G

    2015-07-01

    Spectroscopic methods are increasingly used for monitoring pharmaceutical manufacturing unit operations that involve powder handling and processing. With that regard, chemometric models are required to interpret the obtained spectra. There are many ways to prepare artificial powder blend samples used in a chemometric model for predicting the chemical content. Basically, an infinite number of possible concentration levels exist in terms of the individual components. In our study, design of experiments for ternary mixtures was used to establish a suitable number of blend compositions that represents the entire mixture region of interest for a three component blend. Various experimental designs and their effect on the predictive power of a chemometric model for near infrared spectra were investigated. It was determined that a particular choice of experimental design could change the predictive power of a model, even with the same number of calibration experiments. PMID:25980978

  6. Miscibility of polymer blends with engineering models

    DEFF Research Database (Denmark)

    Vassilis, Harismiadis; van Bergen, A. R. D.; Goncalves, Ana Saraiva;

    1996-01-01

    The miscibility behavior of polymer blends that do not exhibit strong specific interactions is examined. Phase equilibrium calculations are presented with the van der Waals equation of state and three group-contribution models (UNIFAC, Entropic-FV, and GC-Flory). Performance of these models is also...... compared. The van der Waals equation of state was recently shown to accurately correlate and predict vapor-liquid and liquid-liquid equilibria for binary polymer/solvent solutions. In this work, it is demonstrated that it correlates the upper critical solution behavior of polymer blends with excellent......, the upper critical solution temperature can be predicted with an average error of less than 45 degrees C. The van der Waals equation of state can correlate the lower critical solution behavior of polymer blends, using an interaction parameter that is a linear function of temperature. The UNIFAC and...

  7. REVERSE MODELING FOR CONIC BLENDING FEATURE

    Institute of Scientific and Technical Information of China (English)

    Fan Shuqian; Ke Yinglin

    2005-01-01

    A novel method to extract conic blending feature in reverse engineering is presented.Different from the methods to recover constant and variable radius blends from unorganized points, it contains not only novel segmentation and feature recognition techniques, but also bias corrected technique to capture more reliable distribution of feature parameters along the spine curve. The segmentation depending on point classification separates the points in the conic blend region from the input point cloud. The available feature parameters of the cross-sectional curves are extracted with the processes of slicing point clouds with planes, conic curve fitting, and parameters estimation and compensation. The extracted parameters and its distribution laws are refined according to statistic theory such as regression analysis and hypothesis test. The proposed method can accurately capture the original design intentions and conveniently guide the reverse modeling process. Application examples are presented to verify the high precision and stability of the proposed method.

  8. Model for blended learning i de tekniske uddannelser

    DEFF Research Database (Denmark)

    Ringtved, Ulla Lunde; Leth, Lilli-Ann Thomsen; Olsen, Frank;

    2012-01-01

    Anvendelse af blended learning i de tekniske uddannelser i UCN med udgangspunkt i bygningskonstruktøruddannelsen......Anvendelse af blended learning i de tekniske uddannelser i UCN med udgangspunkt i bygningskonstruktøruddannelsen...

  9. COMPOSITION CHANGES IN REFRIGERANT BLENDS FOR AUTOMOTIVE AIR CONDITIONING

    Science.gov (United States)

    Three refrigerant blends used to replace CFC-12 in automotive air conditioners were evaluated for composition changes due to typical servicing and leakage. When recommended service procedures were followed, changes in blend compositions were relatively small. Small changes in b...

  10. Reactive modification of polyesters and their blends

    Science.gov (United States)

    Wan, Chen

    2004-12-01

    As part of a broader research effort to investigate the chemical modification of polyesters by reactive processing a low molecular weight (MW) unsaturated polyester (UP) and a higher MW saturated polyester, polyethylene terephthalate (PET), alone or blended with polypropylene (PP) were melt processed in a batch mixer and continuous twin screw extruders. Modification was monitored by on-line rheology and the products were characterized primarily by off-line rheology, morphology and thermal analysis. Efforts were made to establish processing/property relationships and provide an insight of the accompanying structural changes. The overall response of the reactively modified systems was found to be strongly dependent on the component characteristics, blend composition, type and concentrations of reactive additives and processing conditions. The work concluded that UP can be effectively modified through reactive melt processing. Its melt viscosity and MW can be increased through chemical reactions between organic peroxides (POX) and chain unsaturation or between MgO and carboxyl/hydroxyl end groups. Reactive blending of PP/UP blends through peroxide modification gave finer and more uniform morphology than unreacted blends and at a given PP/UP weight ratio more thermoplastic elastomers-like rheological behavior. This is due to the continuously decreasing viscosity ratio of PP/UP towards unity by the competing reactions between POX and the blend components and formation of PP-UP copolymers which serve as in-situ compatibilizers to promote better interfacial adhesion. Kinetics of the competing reactions were analyzed through a developed model. In addition to POX concentration and mixing efficiency, rheology and morphology of UP/PP bends were significantly affected by the addition of inorganic and organic coagents. Addition of coagents such as a difunctional maleimide, MgO and/or an anhydride functionalized PP during reactive blending offers effective means for tailoring

  11. Composites and blends from biobased materials

    Energy Technology Data Exchange (ETDEWEB)

    Kelley, S.S. [National Renewable Energy Laboratory, Golden, CO (United States)

    1995-05-01

    The program is focused on the development of composites and blends from biobased materials to use as membranes, high value plastics, and lightweight composites. Biobased materials include: cellulose derivative microporous materials, cellulose derivative copolymers, and cellulose derivative blends. This year`s research focused on developing an improved understanding of the molecular features that cellulose based materials with improved properties for gas separation applications. Novel cellulose ester membrane composites have been developed and are being evaluated under a collaborative research agreement with Dow Chemicals Company.

  12. Blended Course with Flipped Classroom Approach

    DEFF Research Database (Denmark)

    Timcenko, Olga; Purwins, Hendrik; Triantafyllou, Evangelia;

    2015-01-01

    This paper presents and analyses design decisions and development process of producing teaching materials for a blended course with flipped classroom approach at bachelor level at Aalborg University in Copenhagen, Denmark. Our experiences, as well as students’ reactions and opinions will be descr......This paper presents and analyses design decisions and development process of producing teaching materials for a blended course with flipped classroom approach at bachelor level at Aalborg University in Copenhagen, Denmark. Our experiences, as well as students’ reactions and opinions...

  13. Statistical methods for assessment of blend homogeneity

    DEFF Research Database (Denmark)

    Madsen, Camilla

    2002-01-01

    In this thesis the use of various statistical methods to address some of the problems related to assessment of the homogeneity of powder blends in tablet production is discussed. It is not straight forward to assess the homogeneity of a powder blend. The reason is partly that in bulk materials as...... shown how to set up parametric acceptance criteria for the batch that gives a high confidence that future samples with a probability larger than a specified value will pass the USP threeclass criteria. Properties and robustness of proposed changes to the USP test for content uniformity are investigated...

  14. Blended Learning or E-learning?

    OpenAIRE

    Tayebinik, Maryam; Puteh, Marlia

    2013-01-01

    ICT or Information and Communication Technology has pervaded the fields of education.In recent years the term e-learning has emerged as a result of the integration of ICT in the education fields. Following the application this technology into teaching, some pitfalls have been identified and this have led to the Blended learning phenomenon.However the preference on this new method has been debated quite extensively.The aim of this paper is to investigate the advantages of blended learning over...

  15. COMPUTATION OF VECTOR VALUED BLENDING RATIONAL INTERPOLANTS

    Institute of Scientific and Technical Information of China (English)

    檀结庆

    2003-01-01

    As we know, Newton's interpolation polynomial is based on divided differ-ences which can be calculated recursively by the divided-difference scheme while Thiele'sinterpolating continued fractions are geared towards determining a rational functionwhich can also be calculated recursively by so-called inverse differences. In this paper,both Newton's interpolation polynomial and Thiele's interpolating continued fractionsare incorporated to yield a kind of bivariate vector valued blending rational interpolantsby means of the Samelson inverse. Blending differences are introduced to calculate theblending rational interpolants recursively, algorithm and matrix-valued case are dis-cussed and a numerical example is given to illustrate the efficiency of the algorithm.

  16. To blend or not to blend?! That’s the e-learning question!

    OpenAIRE

    Gil, Henrique

    2009-01-01

    This paper aims to discuss and reflect about the importance of blended learning. Today blended learning became very popular but it is important find the best ways and the best types to deliver and ”consume ”it. It is common recognize blended learning as a mix of media and delivery. However there is very important to find out the “right mix” because it is known that different problems need different solutions. When we talk about higher education we deal with adults and we assume that students ...

  17. Systematic Methodology for Design of Tailor-Made Blended Products: Fuels and Other Blended Products

    DEFF Research Database (Denmark)

    Yunus, Nor Alafiza Binti

    A tailor-made blended liquid product is defined as a formulation of various chemicals in the liquid state to obtain a liquid mixture with a specific set of desired characteristics and qualities. Examples of blended liquid products are synthetic fuels and lubricants. This type of products is very ...... methodology and tools was tested through two case studies. In the first case study, two different gasoline blend problems have been solved. In the second case study, four different lubricant design problems have been solved....

  18. Effect of Blending Ratio on the Properties of Ramie/Polyester Blended Yarn

    Institute of Scientific and Technical Information of China (English)

    YU Wen

    2002-01-01

    The effects of the blending ratio on the properties of Ramie/Polyester blended yarns are discussed in this paper. The experimental results show that the elongation of the yarn with the polyester content more than 40% is better than that of others. There is a lowest tenacity of the yarn corresponding to the blending ratio of 50/50 or so. The other properties of the yarn, such as the evenness and hairiness, will be improved with the increasing of the polyester content.

  19. THE DEFORMABILITY OF POLYCARBONATE/ POLY(ETHYLENE TEREPHTHALATE) BLENDS

    OpenAIRE

    Mikitaev, Muslim; Kozlov, Georgiy; Howell, Bob; Zaikov, Gennadiy; Mikitaev, Abdulah

    2015-01-01

    It has been shown that the extreme enhancement of strain at break for blends polycarbonate/poly(ethylene terephthalate) blends is due to the corresponding structural changes of the indicated blends, which are characterized by their structure fractal dimension variation. The blends deformability rise can be achieved by enhancement of either Flory-Huggins interaction parameter, or shear strength of their autohesional contact. The transparence threshold of macromolecular coils achievement result...

  20. Blended learning in Saudi universities: challenges and perspectives

    OpenAIRE

    Alebaikan, Reem; Troudi, Salah

    2011-01-01

    This study is an attempt to investigate the nature of obstacles and challenges encountered at Saudi universities while implementing a blended learning approach. A literature review of blended learning rationale and designs, and the status of web-based education in Saudi higher education are demonstrated. Three main challenges of applying blended learning in Saudi higher education are addressed. One major challenge to be considered in the implementation of blended learning in Saudi universitie...

  1. THERMAL BEHAVIOR OF THERMOTROPIC HYDROXYETHYL CELLULOSE ACETATE/POLYETHYLENE BLENDS

    Institute of Scientific and Technical Information of China (English)

    WANG Hailin; CHEN Jinming; HUANG Yong; SHEN Jiarui

    1997-01-01

    The thermal behavior of thermotropic hydroxyethyl cellulose acetate (HECA)/polyethylene (PE) blends has been studied by DSC. It is found that the blends of HECA and PE are immiscible but the crystallization of PE is affected by HECA chains in the blends with more than 50% HECA, which results in the subordinate crystallization of PE and the formation of imperfect structures in the PE crystals. The imperfection of PE crystals in the blends can be eliminated after annealing at 393K.

  2. Blended Learning within an Undergraduate Exercise Physiology Laboratory

    Science.gov (United States)

    Elmer, Steven J.; Carter, Kathryn R.; Armga, Austin J.; Carter, Jason R.

    2016-01-01

    In physiological education, blended course formats (integration of face-to-face and online instruction) can facilitate increased student learning, performance, and satisfaction in classroom settings. There is limited evidence on the effectiveness of using blending course formats in laboratory settings. We evaluated the impact of blended learning…

  3. Transitioning to Blended Learning: Understanding Student and Faculty Perceptions

    Science.gov (United States)

    Napier, Nannette P.; Dekhane, Sonal; Smith, Stella

    2011-01-01

    This paper describes the conversion of an introductory computing course to the blended learning model at a small, public liberal arts college. Blended learning significantly reduces face-to-face instruction by incorporating rich, online learning experiences. To assess the impact of blended learning on students, survey data was collected at the…

  4. 27 CFR 24.213 - Heavy bodied blending wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Heavy bodied blending wine. 24.213 Section 24.213 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Other Than Standard Wine § 24.213 Heavy bodied blending wine. Heavy bodied blending wine...

  5. THE RADIATION CROSSLINKING OF EPR/SBR BLEND

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wanxi; L(U) Yingtao; SUN Jiazhen

    1990-01-01

    The radiation crosslinking of EPR/SBR blend has been studied. A relationship between sol fraction and radiation dose for the different weight ratio polymer blends and the method to calculate βb value of EPR/SBR blend system have been established.

  6. 21 CFR 133.167 - Pasteurized blended cheese.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Pasteurized blended cheese. 133.167 Section 133...) FOOD FOR HUMAN CONSUMPTION CHEESES AND RELATED CHEESE PRODUCTS Requirements for Specific Standardized Cheese and Related Products § 133.167 Pasteurized blended cheese. Pasteurized blended cheese conforms...

  7. HEU to LEU conversion and blending facility: Metal blending alternative to produce LEU oxide for disposal

    International Nuclear Information System (INIS)

    US DOE is examining options for disposing of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials. The nuclear material is converted to a form more proliferation- resistant than the original form. Blending HEU (highly enriched uranium) with less-enriched uranium to form LEU has been proposed as a disposition option. Five technologies are being assessed for blending HEU. This document provides data to be used in environmental impact analysis for the HEU-LEU disposition option that uses metal blending with an oxide waste product. It is divided into: mission and assumptions, conversion and blending facility descriptions, process descriptions and requirements, resource needs, employment needs, waste and emissions from plant, hazards discussion, and intersite transportation

  8. Miscibility of polymer blends with engineering models

    DEFF Research Database (Denmark)

    Vassilis, Harismiadis; van Bergen, A. R. D.; Goncalves, Ana Saraiva; Kontogeorgis, Georgios; Fredenslund, Aage; Dimitrios, Tassios

    1996-01-01

    The miscibility behavior of polymer blends that do not exhibit strong specific interactions is examined. Phase equilibrium calculations are presented with the van der Waals equation of state and three group-contribution models (UNIFAC, Entropic-FV, and GC-Flory). Performance of these models is also...

  9. Chitosan films and blends for packaging material

    NARCIS (Netherlands)

    Broek, van den L.A.M.; Knoop, J.R.I.; Kappen, F.H.J.; Boeriu, C.G.

    2015-01-01

    An increased interest for hygiene in everyday life as well as in food, feed and medical issues lead to a strong interest in films and blends to prevent the growth and accumulation of harmful bacteria. A growing trend is to use synthetic and natural antimicrobial polymers, to provide non-migratory an

  10. Nitrate Salt Surrogate Blending Scoping Test Plan

    Energy Technology Data Exchange (ETDEWEB)

    Anast, Kurt Roy [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-13

    Test blending equipment identified in the “Engineering Options Assessment Report: Nitrate Salt Waste Stream Processing”. Determine if the equipment will provide adequate mixing of zeolite and surrogate salt/Swheat stream; optimize equipment type and operational sequencing; impact of baffles and inserts on mixing performance; and means of validating mixing performance

  11. Comparative Blended Learning Practices and Environments

    Science.gov (United States)

    Ng, Eugenia M. W., Ed.

    2010-01-01

    With the advent of new technologies, more convenient and effective ways of learning are being adopted. However, despite the growing advancements there remains a lack of literature in applications of using these technology teaching approaches. This book offers in-depth analysis of new technologies in blended learning that promote creativity,…

  12. Evaluating What Works in Blended Learning

    Science.gov (United States)

    Education Week, 2012

    2012-01-01

    Blended learning--the mix of virtual education and face-to-face instruction--is evolving quickly in schools across the country, generating a variety of different models. This special report, the second in a three-part 2012-13 series on virtual education, examines several of those approaches and aims to identify what is working and where…

  13. High School Students' Views on Blended Learning

    Science.gov (United States)

    Yapici, Ibrahim Umit; Akbayin, Hasan

    2012-01-01

    In this study, it is aimed to determine the high school students' views on blended learning. The study was carried out in biology course for the lesson unit of "Classification of Living Things and Biodiversity" with 47 9[superscript th] grade students attending Nevzat Ayaz Anatolian High School in the second term of the academic year of 2009-2010.…

  14. The Effectiveness of Blended Learning Environments

    Science.gov (United States)

    Eryilmaz, Meltem

    2015-01-01

    The object of this experimental study is to measure the effectiveness of a blended learning environment which is laid out on the basis of features for face to face and online environments. The study was applied to 110 students who attend to Atilim University, Ankara, Turkey and take Introduction to Computers Course. During the application,…

  15. Transactional Distance in a Blended Learning Environment

    Science.gov (United States)

    Dron, Jon; Seidel, Catharine; Litten, Gabrielle

    2004-01-01

    This paper presents a case study that describes and discusses the problems encountered during the design and implementation of a blended learning course, largely taught online through a web-based learning environment. Based on Moore's theory of transactional distance, the course was explicitly designed to have dialogue at its heart. However, the…

  16. Blended learning tools for teaching and training

    CERN Document Server

    Allan, Barbara

    2007-01-01

    Offers a holistic blended learning approach, combining the best of traditional approaches to learning and teaching to make best use of the advantages of each while minimizing the disadvantages. It provides information professionals with a practical guide to the design and delivery of such training programmes.

  17. The Optimum Blend: Affordances and Challenges of Blended Learning For Students

    OpenAIRE

    Nuray Gedik; Ercan Kiraz; M.Yaşar ÖZDEN

    2012-01-01

    The purpose of this study was to elicit students’ perceptions regarding the most facilitative and most challenging features (affordances and barriers) in a blended course design. Following the phenomenological approach of qualitative inquiry, data were collected from ten undergraduate students who had experiences in a blended learning environment. Data were collected from the students’ weekly reflection papers, interviews with students, and documents, and analyzed by structurally and textural...

  18. HEU to LEU conversion and blending facility: UNH blending alternative to produce LEU oxide for disposal

    International Nuclear Information System (INIS)

    The United States Department of Energy (DOE) is examining options for the disposition of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials. Disposition is a process of use or disposal of material that results in the material being converted to a form that is substantially and inherently more proliferation-resistant than is the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. This report provides data to be used in the environmental impact analysis for the uranyl nitrate hexahydrate blending option to produce oxide for disposal. This the Conversion and Blending Facility (CBF) alternative will have two missions (1) convert HEU materials into HEU uranyl nitrate (UNH) and (2) blend the HEU uranyl nitrate with depleted and natural assay uranyl nitrate to produce an oxide that can be stored until an acceptable disposal approach is available. The primary emphasis of this blending operation will be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. The blended LEU will be produced as a waste suitable for storage or disposal

  19. Intermediate Ethanol Blends Catalyst Durability Program

    Energy Technology Data Exchange (ETDEWEB)

    West, Brian H; Sluder, Scott; Knoll, Keith; Orban, John; Feng, Jingyu

    2012-02-01

    In the summer of 2007, the U.S. Department of Energy (DOE) initiated a test program to evaluate the potential impacts of intermediate ethanol blends (also known as mid-level blends) on legacy vehicles and other engines. The purpose of the test program was to develop information important to assessing the viability of using intermediate blends as a contributor to meeting national goals for the use of renewable fuels. Through a wide range of experimental activities, DOE is evaluating the effects of E15 and E20 - gasoline blended with 15% and 20% ethanol - on tailpipe and evaporative emissions, catalyst and engine durability, vehicle driveability, engine operability, and vehicle and engine materials. This report provides the results of the catalyst durability study, a substantial part of the overall test program. Results from additional projects will be reported separately. The principal purpose of the catalyst durability study was to investigate the effects of adding up to 20% ethanol to gasoline on the durability of catalysts and other aspects of the emissions control systems of vehicles. Section 1 provides further information about the purpose and context of the study. Section 2 describes the experimental approach for the test program, including vehicle selection, aging and emissions test cycle, fuel selection, and data handling and analysis. Section 3 summarizes the effects of the ethanol blends on emissions and fuel economy of the test vehicles. Section 4 summarizes notable unscheduled maintenance and testing issues experienced during the program. The appendixes provide additional detail about the statistical models used in the analysis, detailed statistical analyses, and detailed vehicle specifications.

  20. Silk fibroin/pullulan blend films: Preparation and characterization

    Science.gov (United States)

    Shivananda, C. S.; Rao, B. Lakshmeesha; Madhukumar, R.; Sarojini, B. K.; Somashekhar, R.; Asha, S.; Sangappa, Y.

    2016-05-01

    In this work silk fibroin/pullulan blend films have been prepared by solution casting method. The blend films were examined for structural, and thermal properties using X-ray diffraction (XRD), thermogravimatric (TGA) and differential scanning calorimetry (DSC) analysis. The XRD results indicate that with the introduction of pullulan, the interaction between SF and pullulan in the blend films induced the conformation transition of SF films and amorphous phase increases with increasing pullulan ratio. The thermal properties of the blend films were improved significantly in the blend films.

  1. Design of Sustainable Blended Products using an Integrated Methodology

    DEFF Research Database (Denmark)

    Yunus, Nor Alafiza Binti; Gernaey, Krist; Woodley, John; Gani, Rafiqul

    to be used as building blocks in the mixture design, and then to propose the blend formulations that fulfill the desired product attributes. The result is a set of blends that match the constraints, the compositions, values of the target properties and information about their miscibility. The...... methodology has been applied to design several blended products. A case study on design of blended lubricants is highlighted. The objective is to identify blended products that satisfy the product attributes with at least similar or better performance compared to conventional products....

  2. TIME-DEPENDENT MORPHOLOGY OF POLYETHYLENE-POLYPROPYLENE BLENDS

    Institute of Scientific and Technical Information of China (English)

    Jun Li; Robert A.Shanks; Long Yu

    2002-01-01

    The effect of time-temperature treatment on morphology of polyethylene-polypropylene (PE-PP) blends wasstudied to establish a relationship between thermal history, morphology and mechanical properties. Polypropylene (PP)homopolymers were used to blend with various polyethylenes (PE), including high density polyethylene (HDPE), lowdensity polyethylene (LDPE), linear low density polyethylene (LLDPE), and very and ultra low density polyethylene(VLDPE and ULDPE). The majority of the blends were prepared at a ratio ofPE:PP = 80:20, while blends of PP and LLDPEwere prepared at various compositions. Thermal treatment was carried out at temperatures between the crystallizationtemperatures of PP and PEs to allow PP to crystallize first from the blends. On cooling further, PE crystallized too. A verydiffuse PP spherulite morphology in the PE matrix was formed in some partially miscible blends when PP was less than 20%by mass. Droplet-matrix structures were developed in other blends with either PP or PE as dispersed domains in a continuousmatrix, depending on the composition ratio. The scanning electron microscopy (SEM) images displayed a fibrillar structureof PP spherulite in the LLDPE-PP (80:20) and large droplets of PP in the HDPE-PP (80:20) blend, providing larger surfacearea and better bonding in the LLDPE-PP (80:20) blends. This explains why the blends with diffuse spherulite morphologyshowed greater improvement in tensile properties than droplet-matrix morphology blends after time-temperature treatment.

  3. Performance and emission characteristics of double biodiesel blends with diesel

    Directory of Open Access Journals (Sweden)

    Kuthalingam Arun Balasubramanian

    2013-01-01

    Full Text Available Recent research on biodiesel focused on performance of single biodiesel and its blends with diesel. The present work aims to investigate the possibilities of the application of mixtures of two biodiesel and its blends with diesel as a fuel for diesel engines. The combinations of Pongamia pinnata biodiesel, Mustard oil biodiesel along with diesel (PMD and combinations of Cotton seed biodiesel, Pongamia pinnata biodiesel along with diesel (CPD are taken for the experimental analysis. Experiments are conducted using a single cylinder direct-injection diesel engine with different loads at rated 3000 rpm. The engine characteristics of the two sets of double biodiesel blends are compared. For the maximum load, the value of Specific Fuel consumption and thermal efficiency of CPD-1 blend (10:10:80 is close to the diesel values. CPD blends give better engine characteristics than PMD blends. The blends of CPD are suitable alternative fuel for diesel in stationary/agricultural diesel engines.

  4. Engaging with blended learning to improve students' learning outcomes

    Science.gov (United States)

    Francis, Rebecca; Shannon, Susan J.

    2013-08-01

    When blended learning is embraced to enhance learning in engineering (architectural), design and architecture, we argue it is a best-practice instructional mode. Blended learning is the seamless amalgamation of carefully selected online modules with face-to-face instruction. This paper evaluates case studies of the introduction of blended learning in these disciplines. It demonstrates that students who do not engage with blended learning are academically disadvantaged. Alignment of the blended mode of delivery and the mode of assessment is next considered. Two case studies of the introduction of blended modes of assessment, for improved student satisfaction with feedback, are evaluated. Finally, the reliance upon non-faculty to provide both blended learning and assessment is evaluated using qualitative research methods to establish the barriers to adoption of what is now considered best educational practice.

  5. Performance evaluation of gamma irradiated SiR-EPDM blends

    Energy Technology Data Exchange (ETDEWEB)

    Deepalaxmi, R., E-mail: deepalaxmivaithi@gmail.com; Rajini, V.

    2014-07-01

    Highlights: • The effects of gamma irradiation on SiR-EPDM blend are examined. • Cross-linking reaction is dominant in blends C, D and E, due to higher EPDM content. • The tensile strength and hardness of blend E is improved by gamma irradiation. • The blend C and EPDM rich blends (D, E) are found to have superior performance. • Among C, D and E, suitable blend can be selected for a particular NPP application. - Abstract: Cable insulation materials (CIM) should perform their safety functions throughout their installed life in nuclear power plants (NPP). The CIM will be exposed to gamma irradiation at the installed locations. In order to forecast long-term performance of CIM, the short time accelerated testing was carried out. Due to its good mechanical strength, ethylene propylene diene monomer (EPDM) is widely used as CIM. Silicone rubber (SiR) is used in high temperature environments, due to its good di-electric properties/hydrophobicity. The blending of these two polymers may result in the improvement in their specific properties. This paper analyses the effects of gamma irradiation on the five different compositions (90-10; 70-30; 50-50; 30-70; 10-90) of SiR-EPDM blends. The blends were exposed to four different doses (25 Mrad, 100 Mrad, 200 Mrad and 250 Mrad) of gamma irradiation. The electrical and mechanical parameters like volume resistivity (VRY), surface resistivity (SRY), tensile strength (TS), elongation at break (EB), hardness (H) of the virgin and gamma irradiated blends were determined as per ASTM/IEC standards. The nature of degradation was investigated using Fourier transform infrared spectroscopy (FTIR). The simultaneous occurrence of cross-linking and chain scission is found to be the mechanism for ageing in SiR-EPDM blends. The electrical parameters such as volume resistivity and surface resistivity of all the blends are found to improve for all doses of gamma irradiation. To validate the influence of cross-linking reaction of the Si

  6. Tank 21 and Tank 24 Blend and Feed Study: Blending Times, Settling Times, and Transfers

    International Nuclear Information System (INIS)

    The Salt Disposition Integration (SDI) portfolio of projects provides the infrastructure within existing Liquid Waste facilities to support the startup and long term operation of the Salt Waste Processing Facility (SWPF). Within SDI, the Blend and Feed Project will equip existing waste tanks in the Tank Farms to serve as Blend Tanks where salt solutions of up to 1.2 million gallons will be blended in 1.3 million gallon tanks and qualified for use as feedstock for SWPF. In particular, Tanks 21 and 24 are planned to be used for blending and transferring to the SDI feed tank. These tanks were evaluated here to determine blending times, to determine a range of settling times for disturbed sludge, and to determine that the SWPF Waste Acceptance Criteria that less than 1200 mg/liter of solids will be entrained in salt solutions during transfers from the Tank 21 and Tank 24 will be met. Overall conclusions for Tank 21 and Tank 24 operations include: (1) Experimental correction factors were applied to CFD (computational fluid dynamics) models to establish blending times between approximately two and five hours. As shown in Phase 2 research, blending times may be as much as ten times greater, or more, if lighter fluids are added to heavier fluids (i.e., water added to salt solution). As the densities of two salt solutions converge this effect may be minimized, but additional confirmatory research was not performed. (2) At the current sludge levels and the presently planned operating heights of the transfer pumps, solids entrainment will be less than 1200 mg/liter, assuming a conservative, slow settling sludge simulant. (3) Based on theoretical calculations, particles in the density range of 2.5 to 5.0 g/mL must be greater than 2-4 (micro)m in diameter to ensure they settle adequately in 30-60 days to meet the SWPF feed criterion ( 60 days) settling times in Tank 21.

  7. Raman technique application for rubber blends characterization

    Directory of Open Access Journals (Sweden)

    Smitthipong, W.

    2007-11-01

    Full Text Available Raman spectroscopy has been employed in a number of studies to examine the morphological changes in a variety of materials. It is a non-destructive analysis method and an equally useful method for the investigation of material structure. Recently, Raman spectroscopy has been developed to employ as an imaging instrumentation. Sample surface scanning in X- and Y-axis and sample depth (Z-axis can be carried out by modifying the focus of the laser beam from the Raman microscope. Therefore, three-dimensional images can be thus built by using special software. The surface and bulk properties of immiscible rubber blend were investigated by Raman spectroscopy. The results obtained by Raman spectroscopy were in good agreement with those of Scanning Electron Microscope (SEM. The combination of Raman spectrometry and SEM clearly elucidates the identification of phases between the dispersed phase and the matrix (continuous phase of the immiscible rubber blends.

  8. Methanol gasoline blend from petroleum coke sources

    Energy Technology Data Exchange (ETDEWEB)

    Netzer, David [Consulting Chemical Engineer (United States); Wallsgrove, Chris [Process Engineering Manager (United States)

    2011-07-01

    In Alberta, a large amount of petroleum coke is produced as a byproduct from processes relating to bitumen upgrading and refining. Unfortunately, there is little to no market for this product in the province. This presentation addresses concerns relating to the concept of converting the otherwise wasted petcoke into methanol and using it as a blending component in gasoline. The presentation tackles issues relating to environmental impact, economics, renewability, toxicity, safety, and vehicle design by analyzing and comparing the proposed methanol/gasoline (M-10) to that of an ethanol/gasoline (E-10). The presentation covers analysis of the CO2 emissions, an analysis of the finances, and a number of scenarios involving the improper use or accidental spillage of M-10. Through the comparison of methanol/gasoline and ethanol/gasoline, the presentation demonstrated that converting the petcoke byproduct into methanol for use as a gasoline blend is a viable option.

  9. Guidelines for handling and blending FAME

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-11-15

    This report provides guidance on the handling and blending of Fatty Acid Methyl Esters (FAME), as a neat product and at concentrations up to 10% v/v in diesel fuel. The major challenges associated with diesel fuels containing FAME are discussed as they relate to the conformity of the finished fuel to typical specifications, especially those in the European standard for automotive diesel (EN 590). This report focuses on the production, blending, distribution, and supply of diesel containing up to 10% v/v FAME as well as the storage and handling of neat FAME but does not address vehicle-related issues with the use of diesel fuels containing FAME. The potential future production and use of Fatty Acid Ethyl Esters (FAEE) in diesel fuel is also discussed.

  10. A thermodynamic model for blended cements

    International Nuclear Information System (INIS)

    A chemical thermodynamic model has been developed for blended cements, called CEMCHEM. Given the chemical compositions of the blend materials, CEMCHEM calculates the equilibrium phase distribution, achieved at 25oC. It is based on a portion of the CaO-Al2O3- SiO2- SO3- H2O system, whose phase relations have been determined from the results of 'compatibility experiments'. Solubility models have been developed for the cement hydrate phases used in CEMCHEM, for use with the computer codes MINEQL, PHREEQE and EQ3/6. Validation of the overall approach is provided by the agreement between observed and calculated aqueous compositions for the compatibility experiments. Thus CEMCHEM, with the cement hydrate solubility models, can be used as the basis for modelling near field chemistry in cementitious radwaste repositories. (author)

  11. Engineers Create Bone that Blends into Tendons

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Engineers at Georgia Tech have used skin cells to create artificial bones that mimic the ability of natural bone to blend into other tissues such as tendons or ligaments. The artificial bones display a gradual change from bone to softer tissue rather than the sudden shift of previously developed artificial tissue, providing better integration with the body and allowing them to handle weight more successfully.

  12. Transactional distance in a blended learning environment

    OpenAIRE

    Dron, Jon; Seidel, Catharine; Litten, Gabrielle

    2004-01-01

    This paper presents a case study that describes and discusses the problems encountered during the design and implementation of a blended learning course, largely taught online through a web-based learning environment. Based on Moore’s theory of transactional distance, the course was explicitly designed to have dialogue at its heart. However, the reality of systemic behaviours caused by delivering such a course within a group of conventional further and higher educational institutions has led ...

  13. Flow induced coalescence in polymer blends

    Czech Academy of Sciences Publication Activity Database

    Jůza, Josef; Fortelný, Ivan

    2013-01-01

    Roč. 7, č. 1 (2013), s. 53-60. ISSN 1996-4196. [POLYCHAR 20 World Forum on Advanced Materials. Dubrovnik, 26.03.2012-30.03.2012] R&D Projects: GA ČR GAP106/11/1069 Institutional support: RVO:61389013 Keywords : coalescence * polymer blends * extensional flow Subject RIV: BK - Fluid Dynamics http://old.lp.edu.ua//journals/jcct/arkhiv-nomeriv/2013/no-1/

  14. Accommodating and promoting multilingualism through blended learning

    OpenAIRE

    Olivier, Jak

    2011-01-01

    Multilingualism is a reality in South African classrooms. The Constitution of South Africa (Act 108 of 1996) and the national language policy recognize language rights and aims at supporting, promoting and developing the official languages. However, despite the advantages of mother tongue education, English is often chosen as language of learning and teaching at the cost of the African official languages. This study proposes the accommodation and promotion of multilingualism through blended l...

  15. DISCOURSE OF EDUCATION: ONLINE AND BLENDED LEARNING

    OpenAIRE

    PENKOV B.V.

    2015-01-01

    The study examines some features of educational discourse, including the concepts of online and blended learning within the context of high school. The object of research is high school, especially senior high school. The author looks into discourse markers for the use of concepts in the discourse of education. The features differentiate texts, which belong to the educational discourse and its genres as well as show the markers of contemporary discourse within the context. They study analyzes...

  16. Identification of SPV using a Blended Method

    International Nuclear Information System (INIS)

    A Single Point Vulnerability (SPV) may cause plant transients like reactor trip, turbine/ generator trip, orderated power to 50% or more. In order to improve plant reliability and performance by preventing unexpected plant transients, we, KEPCO-ENC and KHNP, are developing SPV monitoring program. To have a better result of the SPV identification and monitoring, we used a blended method which was comprised of qualitative and quantitative approaches. This method is described herein, representative results of SPV identification are presented

  17. Identification of SPV using a Blended Method

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jin Kyu; Lee, Kwang Nam [KEPCO-ENC, Daejeon (Korea, Republic of); Chi, Moon Goo; Lee, Eun Chan [KHNP, Daejeon (Korea, Republic of)

    2010-10-15

    A Single Point Vulnerability (SPV) may cause plant transients like reactor trip, turbine/ generator trip, orderated power to 50% or more. In order to improve plant reliability and performance by preventing unexpected plant transients, we, KEPCO-ENC and KHNP, are developing SPV monitoring program. To have a better result of the SPV identification and monitoring, we used a blended method which was comprised of qualitative and quantitative approaches. This method is described herein, representative results of SPV identification are presented

  18. Characterization of polymer-liquid crystal blends

    OpenAIRE

    DOINA MACOCINSCHI; CRISTOFOR I. SIMIONESCU; DANIELA FILIP

    2001-01-01

    Blends of semi-crystalline polymers (polyethylene adipate and two poly(ester-urethane) s) with liquid crystal cholesteryl palmitate with different compositions were prepared by solution casting. One of the poly(ester-urethane)s was based on 2,4-tolylene diisocyanate (TDI) and the other one on 4,4-diphenylmethane diisocyanate (MDI). The miscibility and phase transition were investigated over the whole range of concentration by differential scanning calorimetry and polarizing optical microscopy.

  19. Phase Segregation in Polystyrene?Polylactide Blends

    OpenAIRE

    Leung, Bonnie

    2011-01-01

    Spun-cast films of polystyrene (PS) blended with polylactide (PLA) were visualized and characterized using atomic force microscopy (AFM) and synchrotron-based X-ray photoemission electron microscopy (X-PEEM). The composition of the two polymers in these systems was determined by quantitative chemical analysis of near-edge X-ray absorption signals recorded with X-PEEM. The surface morphology depends on the ratio of the two components, the total polymer concentration, and the temperature of vac...

  20. Blended learning course to teach word processing

    OpenAIRE

    HAVELKA, Zbyněk

    2011-01-01

    This bachelor thesis deals with the problem of teaching computer science and various approaches to the teaching of the application environment. The work provides a comparison of available textbooks on the issue. Furthermore, in the theoretical part of the bachelor work is design a modern approach to teaching of the application environment. As a practical output of this work is, as its name suggests, the blended learning course to teach word processing, which is designed as a modern approach p...

  1. Facebook: A Versatile Platform for Blended Learning

    OpenAIRE

    Wong Ling Shing; Betty Voon Wan Niu

    2013-01-01

    Facebook is a popular networking tool among the young learners. This paper reports a practical usage of Facebook to engage learners in blended learning. The practical usage of Facebook in hosting online forums, sharing media files in vodcast, building collaborative content through Facebook Doc, and using Facebook as repository for articles and lecture notes has been described. Recent survey on 55 students revealed that a strong majority of the students agreed that Facebook has positive impact...

  2. Blended learning labs practice: magnetic field measurement

    OpenAIRE

    Espinosa Tomás, Julián; Pérez Rodríguez, Jorge; Miret Marí, Juan José; Caballero Caballero, María Teresa; Vázquez Ferri, Carmen; Mas Candela, David; Hernández Poveda, Consuelo; Illueca Contri, Carlos

    2011-01-01

    In the current academic year, the widespread implementation of the new degrees in the Spanish higher education has brought the development and application of new methodologies with the aim of trying to improve the way students learn. In order to promote scientific interest of the students and to help in the improvement of the teaching-learning process of physics, we have scheduled plan blended learning labs. A lab practice that deals with magnetic fields, whose concepts have been already disc...

  3. Phase morphological study on SEBS compatibilized PS/LDPE blends

    Directory of Open Access Journals (Sweden)

    Chatchai Kunyawut

    2014-09-01

    Full Text Available The co-continuous phase morphology of polystyrene (PS/low density polyethylene (LDPE blends compatibilized with poly(styrene-block-ethylene/butylene-block-styrene triblock copolymers (SEBS with varying molecular weights has been investigated. The blend samples were prepared in a mini-twin screw extruder. The barrel length and diameter are 224 and 16 mm, respectively. The diameter of the capillary die is 1 mm. The concentration of the blends was 70/30 wt% of PS/LDPE while that of the SEBS used was 5 wt% of the blend. The mixing temperatures used were 180, 250, and 280o C, and a screw speed of 60 rpm. The morphology of the blends was investigated using an AFM technique. Average droplet diameters of the blend samples were determined using an OM technique. The co-continuous morphology has not been obtained in all the blends, although the mixing temperature used is as high as 280o C. The experimental results indicated that the model prediction of the co-continuous morphology proposed by Willemse and co-worker was not applicable to the blend systems studied. Only droplet-type dispersion was observed. This is considered to arise from the processing conditions and the mixing device used. The blend compatibilized with the high molecular weight SEBS had higher dispersed phase size than that of the blend compatibilized with the medium and low molecular weight SEBSs. This behaviour is likely to arise from coalescence during melt processing.

  4. Tough Blends of Polylactide and Castor Oil

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Megan L.; Paxton, Jessica M.; Hillmyer, Marc A. (UMM)

    2012-10-10

    Poly(l-lactide) (PLLA) is a renewable resource polymer derived from plant sugars with several commercial applications. Broader implementation of the material is limited due to its inherent brittleness. We show that the addition of 5 wt % castor oil to PLLA significantly enhances the overall tensile toughness with minimal reductions in the modulus and no plasticization of the PLLA matrix. In addition, we used poly(ricinoleic acid)-PLLA diblock copolymers, synthesized entirely from renewable resources, as compatibilizers for the PLLA/castor oil blends. Ricinoleic acid, the majority fatty acid comprising castor oil, was polymerized through a lipase-catalyzed condensation reaction. The resulting polymers contained a hydroxyl end-group that was subsequently used to initiate the ring-opening polymerization of L-lactide. The binary PLLA/castor oil blend exhibited a tensile toughness seven times greater than neat PLLA. The addition of block copolymer allowed for control over the morphology of the blends, and even further improvement in the tensile toughness was realized - an order of magnitude larger than that of neat PLLA.

  5. Engineering Polymer Blends for Impact Damage Mitigation

    Science.gov (United States)

    Gordon, Keith L.; Smith, Russell W.; Working, Dennis C.; Siochi, Emilie J.

    2016-01-01

    Structures containing polymers such as DuPont's Surlyn® 8940, demonstrate puncture healing when impacted by a 9 millimeter projectile traveling from speeds near 300 meters per second (1,100 feet per second) to hypervelocity impacts in the micrometeoroid velocity range of 5 kilometers per second (16,000 feet per second). Surlyn® 8940 puncture heals over a temperature range of minus 30 degrees Centigrade to plus 70 degrees Centigrade and shows potential for use in pressurized vessels subject to impact damage. However, such polymers are difficult to process and limited in applicability due to their low thermal stability, poor chemical resistance and overall poor mechanical properties. In this work, several puncture healing engineered melt formulations were developed. Moldings of melt blend formulations were impacted with a 5.56 millimeter projectile with a nominal velocity of 945 meters per second (3,100 feet per second) at about 25 degrees Centigrade, 50 degrees Centigrade and 100 degrees Centigrade, depending upon the specific blend being investigated. Self-healing tendencies were determined using surface vacuum pressure tests and tensile tests after penetration using tensile dog-bone specimens (ASTM D 638-10). For the characterization of tensile properties both pristine and impacted specimens were tested to obtain tensile modulus, yield stress and tensile strength, where possible. Experimental results demonstrate a range of new puncture healing blends which mitigate damage in the ballistic velocity regime.

  6. Blended learning. Conceptos básicos

    Directory of Open Access Journals (Sweden)

    Antonio Bartolomé Pina

    2004-01-01

    Full Text Available En los últimos dos años ha aparecido un nuevo concepto que surge con fuerza en el ámbito de la formación: «Blended Learning». Literalmente podríamos traducirlo como «aprendizaje mezclado» y la novedad del término no se corresponde con la tradición de las prácticas que encierra. Otras denominaciones se han utilizado antes para la misma idea. Y a veces otras ideas se están utilizando para esta misma denominación. ¿Estamos ante un simple recurso de propaganda y venta? ¿Aporta algo a nuestras acción formativa? Este artículo trata de ayudar a comprender que se entiende por «Blended Learning» y a entresacar algunas de las aportaciones que nos pueden enriquecer. Tras estudiar el blended learning como respuesta a los problemas que encuentra el elearning y la enseñanza tradicional, se analizan sus posibilidades y sus características. El artículo termina con una reflexión sobre la razón de la necesidad de este modelo más allá de los motivos economicistas o didácticos.

  7. An Summarization on Blended Learning%Blended Learning初步研究

    Institute of Scientific and Technical Information of China (English)

    田世生; 傅钢善

    2004-01-01

    混合式学习(Blended Learning)的核心目的就是要将传统的课堂式学习和e-Learning的优势相结合.从2001年国外e-Learning开始进入低潮后,国外教育技术界和企业培训界便试图用混合式学习来辅助和改造传统的e-Learning.现在混合式学习已成为教育技术界高度关注的热点.本文拟从Blended Learning的基本问题、设计一个Blended Learning课程的方法以及其对教育技术学带来的反思等方面作一个综述.

  8. Studies on poly (hydroxy alkanoates)/(ethylcellulose) blends

    Indian Academy of Sciences (India)

    Vaishali Suthar; Arun Pratap; Heta Raval

    2000-06-01

    Biodegradable polymers represent one of the most significant area of research today. Among these polymers, poly (-hydroxy butyrate co '-hydroxy valerate) i.e. PHBV have received special attention because of their unique combination of properties. They are perfectly biocompatible, biodegradable polymers and can be processed by any conventional technique. In the present study an attempt has been made to develop the biodegradable blends of PHBV by blending them with ethyl cellulose (EC). Ethyl cellulose has been selected to monitor the biodegradation rate of PHBV and also for making the blends cost effective. The blends are thoroughly characterized for their compatibility, by the measurement of viscosity of blends and through FT-IR. Various applications of PHBV/EC blend in agriculture and pharmaceutical industries are being explored.

  9. Oxidative stability of diacylglycerol oil and butter blends containing diacylglycerols

    DEFF Research Database (Denmark)

    Kristensen, Janni Brogaard; Nielsen, Nina Skall; Jacobsen, Charlotte;

    2006-01-01

    Diacylglycerol (DAG) oils produced from sunflower oil and traditional sunflower oil were stored for 20 wk at 38 degrees C, and their oxidative stability was measured. Moreover, two butter blends were produced containing 40 wt-% DAG oil made from sunflower oil or rapeseed oil, respectively, as well...... as two control butter blends with sunflower oil or rapeseed oil. Their oxidative stability during storage at 5 degrees C for up to 12 wk was examined by similar means as for the pure oils. The storage study of the oils indicated that the DAG oil was oxidatively less stable as compared to sunflower...... oil, but that they had similar sensory quality. Storage of the butter blends revealed that blends with the two types of rapeseed oil (triacylglycerol (TAG) or DAG oil) were oxidatively more stable than the blends containing oils from sunflower. There was no unambiguous indication of DAG butter blends...

  10. FTIR Study of Enhanced Polymeric Blend Membrane with Amines

    Directory of Open Access Journals (Sweden)

    Asim Mushtaq

    2014-03-01

    Full Text Available In this study, research will be carried out to identify the functional group behavior of glassy and rubbery polymeric blend membrane with amines. Polymeric blend membranes with different blending ratios were prepared and the developed membranes were characterized by FTIR to see the effect of blend ratio on different functional groups. The developed membranes are flat dense sheet membrane of 20% wt/wt. The pure and blend membrane polysulfone, polyethersulfone, polyvinyl acetate with different composition, with 10% methyl diethanol amine, mono ethanol amine, diethanol amine are developed with dimethyl acetamide solvent. Fourier Transform Infrared (FTIR spectroscopy was utilized to study the interaction between two polymers and to analyze the type of bonding present. To observed frequencies were assigned to various mode of vibration in terms of fundamentals and combination. These spectral changes indicated the existence of molecular interaction among the enhanced polymeric blends; highlight the compatible nature among each other.

  11. Preparation and characterization of chitosan - polystyrene polymer blends

    Science.gov (United States)

    Mascarenhas, N. P.; Gonsalves, R. A.; Goveas, J. J.; Shetty, T. C. S.; Crasta, V.

    2016-05-01

    To enhance the physical and mechanical properties of Chitosan (CS) and to improve the functionality of CS towards some specific applications, we have blended CS with polystyrene (PS) to form blended films. The Fourier Transform Infrared Spectroscopy (FT-IR) has been performed on the prepared films to confirm functional groups and formation of the blends. Thermal analysis (TGA and DSC) is carried out to study thermal stability of the blended films. From X-ray diffraction (XRD) studies, the material reveals amorphous nature and hence it may be used for adsorption process. The versatility of the blends, such as film-forming ability, hydrophilicity, biodegradability and biocompatibility are comparable with the existing blends.

  12. Blending effects on coal burnout and NO emissions

    Energy Technology Data Exchange (ETDEWEB)

    B. Arias; R. Backreedy; A. Arenillas; J.M. Jones; F. Rubiera; M. Pourkashanian; A. Williams; J.J. Pis [Instituto Nacional del Carbon, CSIC Oviedo (Spain)

    2003-07-01

    In this work, the combustion behaviour of individual coals of different rank and their blends was evaluated. The study was focused on burnout and NO emissions during blend combustion. Preliminary combustion tests of the coals and their blends were carried out in a thermogravimetric analyser (TGA). Some characteristic temperatures were obtained to evaluate the combustibility of the samples. These temperatures indicate an improvement in the combustibility of the less reactive coal when it is blended. An entrained flow reactor (EFR) was employed to study the behaviour of the samples at high heating rates and short residence times. Burnout and NO emissions were measured during EFR combustion tests. In some blends the results can be predicted from the weighted average of the values of the individual coals. However, other blends show an increase, from the averaged values, in burnout and especially in NO emissions. 14 refs., 10 figs., 3 tabs.

  13. Design of Sustainable Blended Products using an Integrated Methodology

    DEFF Research Database (Denmark)

    Yunus, Nor Alafiza Binti; Gernaey, Krist; Woodley, John; Gani, Rafiqul

    This paper presents a systematic methodology for designing blended products consisting of three stages; product design, process identification and experimental verification. The product design stage is considered in this paper. The objective of this stage is to screen and select suitable chemicals...... to be used as building blocks in the mixture design, and then to propose the blend formulations that fulfill the desired product attributes. The result is a set of blends that match the constraints, the compositions, values of the target properties and information about their miscibility. The...... methodology has been applied to design several blended products. A case study on design of blended lubricants is highlighted. The objective is to identify blended products that satisfy the product attributes with at least similar or better performance compared to conventional products....

  14. Structuring polymer blends with bicontinuous phase morphology. Part II. Tailoring blends with ultralow critical volume fraction

    DEFF Research Database (Denmark)

    Lyngaae-Jørgensen, Jørgen; Utracki, Leszek

    2003-01-01

    A hypothesis providing a guideline for the development of immiscible polymer blends with co-continuous phase structure at very low critical volume fraction of one component is. postulated and experimentally verified. Based on a number of simplifying assumptions the following relation was derived......: phi(cr) = k(lambdagamma)(1-z)/(theta(b)(*))(z) where lambdagamma is a Deborah number and theta(b)(*) is a dimensionless break-up time. The equation parameters, k and z are constant that depend on the flow field hence on the blending equipment. For the studies an internal mixer with Walzenkneter...

  15. Blend for visual studio 2012 by example beginner's guide

    CERN Document Server

    Shukla, Abhishek

    2015-01-01

    This book is aimed at developers and designers who are new to Blend and looking to learn Blend, not just practically, but also conceptually. This book does not assume any knowledge about Blend on the part of developers; however, some experience in design or development might be useful in understanding the concepts faster, but this book explains everything very simply so that you are able to understand everything with little or no effort.

  16. Design and evaluation of two blended learning approaches: Lessons learned

    OpenAIRE

    Cheung, WS; Hew, KF

    2011-01-01

    In this paper, we share two blended learning approaches used at the National Institute of Education in Singapore. We have been using these two approaches in the last twelve years in many courses ranging from the diploma to graduate programs. For the first blended learning approach, we integrated one asynchronous communication tool with face to face tutorials, classroom discussions, and a reflection session. For the second blended learning approach, we integrated two asynchronous tools with fa...

  17. Blended learning as an effective pedagogical paradigm for biomedical science

    OpenAIRE

    Hartfield, Perry

    2013-01-01

    Blended learning combines face-to-face class based and online teaching and learning delivery in order to increase flexibility in how, when, and where students study and learn. The development, integration, and promotion of blended learning in frameworks of curriculum design can optimize the opportunities afforded by information and communication technologies and, concomitantly, accommodate a broad range of student learning styles. This study critically reviews the potential benefits of blende...

  18. READINESS FOR BLENDED LEARNING: UNDERSTANDING ATTITUDE OF UNIVERSITY STUDENTS

    OpenAIRE

    Chun Meng Tang; Lee Yen Chaw

    2013-01-01

    Information technology (IT) has provided new means for learning delivery outside of conventional classrooms. Leveraging on IT, blended learning is an approach which takes advantage of the best that both the classroom and online learning can provide. To help institutions of higher learning (IHLs) improve their understanding of how students view blended learning and formulate a strategy to successfully implement blended learning, the main objective of this paper is to examine how the attitude o...

  19. COMBLE: European Community of Integrative Blended Learning Experts

    OpenAIRE

    Niemczik, Christian; Brenstein, Elke; Scholl, Margit

    2008-01-01

    The COMBLE project defines new and innovative models for the use of Blended learning in different educational backgrounds (vocational training, enterprises, universities, public bodies). To use the potentials of Blended learning a European wiki-based community called Methopedia will be established. By contributing to the development of Blended learning COMBLE supports ICT relevant methods that are indispensable for lifelong learning in Europe. Moreover, COMBLE will address to management-level...

  20. Blended learning in health education: three case studies

    OpenAIRE

    Jong, Nynke de; Savin-Baden, Maggi; Cunningham, Anne Marie; Verstegen, Daniëlle M. L.

    2014-01-01

    Blended learning in which online education is combined with face-to-face education is especially useful for (future) health care professionals who need to keep up-to-date. Blended learning can make learning more efficient, for instance by removing barriers of time and distance. In the past distance-based learning activities have often been associated with traditional delivery-based methods, individual learning and limited contact. The central question in this paper is: can blended learning be...

  1. Blending Learning与创新人才培养

    Institute of Scientific and Technical Information of China (English)

    石小云; 肖伟

    2006-01-01

    Blending Learning这一新概念的提出和被广泛认同,真正深化了学校教学改革,达到培养创新人才的目标.本文从Blending Learning和创新人才的涵义及关系探讨了Blending Learning对培养创新人才的重要意义.

  2. Enhancing the blended learning experience of Calculus I students

    OpenAIRE

    Al-Ghassani, A; H. Al Shamsi; Islam, M.; N. Al-Salti; I. Al-Hasni

    2015-01-01

    Blended Learning showed in the last two decades to be one of the effective ways in education and training. We illustrate our initiative experience with blended learning in the course Calculus I. The main goals we want to achieve are improving students understanding of the course concepts, increasing the level of uniformity in this multi-sections course and enhancing students blended learning experience online and offline. Consequently, this affects positively students' academic performance. W...

  3. Performance of wet process method alternatives : terminal or continuous blend

    OpenAIRE

    Fontes, Liseane P. T. L.; Pereira, Paulo A. A.; Pais, Jorge C.; Trichês, Glicério

    2006-01-01

    This study presents the results of the research to investigate asphalt rubber mixtures produced with asphalt rubber binder obtained from two different processes; (i) terminal blend (produced in refinery); (ii) continuous blend (produced in laboratory). The experiment included the evaluation of fatigue and permanent deformation resistance of two gap graded mixtures (Caltrans ARHM -GG; ADOT AR-A C) and a dense gradation Asphalt Institute (AI) mix type IV) Two asphalt rubbers from terminal blend...

  4. Miscibility Phase Diagram of Ring Polymer Blends: A Topological Effect

    OpenAIRE

    Sakaue, Takahiro; Nakajima, Chihiro H.

    2016-01-01

    The miscibility of polymer blends, a classical problem in polymer science, may be altered, if one or both of the component do not have chain ends. Based on the idea of {\\it topological volume}, we propose a mean-field theory to clarify how the topological constraints in ring polymers affect the phase behavior of the blends. While the large enhancement of the miscibility is expected for ring-linear polymer blends, the opposite trend toward demixing, albeit comparatively weak, is predicted for ...

  5. Comparison of Hybrid Blends for Solar Cell Application

    OpenAIRE

    Maria C. Lechmann; Dominik Koll; Daniel Kessler; Patrick Theato; Wolfgang Tremel; Gutmann, Jochen S.

    2010-01-01

    In blended hybrid systems distinct micro- or nanostructured materials can be formed by phase separation. Network structures of particles or rods in a polymer matrix can be developed via self-assembly. We use this blending approach to compare active materials for application in solar cell devices. Blends were fabricated from either poly(hexylthiophene) P3HT or poly(triphenylamine) PTPA mixed with nanocrystalline TiO 2 rods. In this manner, we compare two different hole conducting polymers in t...

  6. Miscibility and Dynamic Mechanical Behavior of Blends with LCP'S

    OpenAIRE

    Gabellini, G.; Suman Bretas, R.

    1996-01-01

    The main advantage of the "in situ" production of blends of thermoplastics with liquid crystalline polymers (LCP's) is viscosity reduction. In this work the phase behavior of blends of poly p-phenylene sulphide (PPS) with two different LCP's is presented. The LCP's are HX1000 (amorphous) and HX4000, crystalline, both from DuPont. The samples were prepared by injection molding and its dynamic mechanical properties were tested after annealing. It was observed that before annealing the blends we...

  7. Emissions characteristics of higher alcohol/gasoline blends

    International Nuclear Information System (INIS)

    An experimental investigation was conducted to determine the emissions characteristics of higher alcohols and gasoline (UTG96) blends. While lower alcohols (methanol and ethanol) have been used in blends with gasoline, very little work has been done or reported on higher alcohols (propanol, butanol and pentanol). Comparisons of emissions and fuel characteristics between higher alcohol/gasoline blends and neat gasoline were made to determine the advantages and disadvantages of blending higher alcohols with gasoline. All tests were conducted on a single-cylinder Waukesha Cooperative Fuel Research engine operating at steady state conditions and stoichiometric air-fuel (A/F) ratio. Emissions test were conducted at the optimum spark timing-knock limiting compression ratio combination for the particular blend being tested. The cycle emission [mass per unit time (g/h)] of CO, CO2 and organic matter hydrocarbon equivalent (OMHCE) from the higher alcohol/gasoline blends were very similar to those from neat gasoline. Cycle emissions of NOx from the blends were higher than those from neat gasoline. However, for all the emissions species considered, the brake specific emissions (g/kW h) were significantly lower for the higher alcohol/gasoline blends than for neat gasoline. This was because the blends had greater resistance to knock and allowed higher compression ratios, which increased engine power output. The contribution of alcohols and aldehydes to the overall OMHCE emissions was found to be minimal. Cycle fuel consumption (g/h) of higher alcohol/gasoline blends was slightly higher than with neat gasoline due to the lower stoichiometric A/F ratios required by the blends. However, the brake specific fuel consumption (g/kW h) for the blends was significantly lower than that for neat gasoline. (Author)

  8. Blended e-learning Design: Discussion of Cultural Issues

    OpenAIRE

    Ahmed AL-Hunaiyyan; Nabeel Al-Huwail; Salah Al-Sharhan

    2008-01-01

    Blended e-learning is becoming an educational issue especially with the new development of e-learning technology and globalization. Educators as the question: can we design these systems to accommodate different cultural groups and various learning strategies. This paper addresses some design issues when selecting a blended e-learning approach; it discusses some cultural elements that affect the design of blended e-learning. The paper also explores issues related to learning design, then emph...

  9. READINESS FOR BLENDED LEARNING: UNDERSTANDING ATTITUDE OF UNIVERSITY STUDENTS

    Directory of Open Access Journals (Sweden)

    Chun Meng Tang

    2013-12-01

    Full Text Available Information technology (IT has provided new means for learning delivery outside of conventional classrooms. Leveraging on IT, blended learning is an approach which takes advantage of the best that both the classroom and online learning can provide. To help institutions of higher learning (IHLs improve their understanding of how students view blended learning and formulate a strategy to successfully implement blended learning, the main objective of this paper is to examine how the attitude of students towards different learning aspects could influence their readiness for blended learning. We conceptualized six learning aspects in a research model and then collected responses from 201 full-time undergraduate students to validate the model. Analyses revealed three key findings. First, the use of technology in education was not a hindrance to the students. Second, blended learning adaptability, which was modelled as a second-order formative construct and formed by four first-order reflective constructs—attitude towards online learning, study management, online interaction, and learning flexibility—had a positive relationship with student readiness for blended learning. Third, attitude towards classroom learning had a negative relationship with student readiness for blended learning. An understanding of student attitude towards different learning aspects can be critical in the assessment of student readiness for blended learning, which is a prerequisite for successful implementation of blended learning.

  10. Morphology-mechanical Property Relationship of Polypropylene/starch Blends

    OpenAIRE

    C.H. Azhari; Wong, S F

    2001-01-01

    The influence of morphology on mechanical property of several polypropylene/starch (PP/starch) blends of varying compositions was studied. The blends prepared were at wt%PP/wt%starch of 97.5/2.5, 95/5, 92.5/7.7, 90/10, 87.5/12.5 and 85/15. The morphology of the blends observed, using scanning electron microscopy showed them to be immiscible blends with distinct polymer-starch domains at high starch volume fractions (85%PP/15%starch-87.5%PP/12.5%starch), which gradually showed the morphology o...

  11. Silk fibroin and sodium alginate blend: Miscibility and physical characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Agostini de Moraes, Mariana; Silva, Mariana Ferreira; Weska, Raquel Farias; Beppu, Marisa Masumi, E-mail: beppu@feq.unicamp.br

    2014-07-01

    Films of silk fibroin (SF) and sodium alginate (SA) blends were prepared by solution casting technique. The miscibility of SF and SA in those blends was evaluated and scanning electron microscopy (SEM) revealed that SF/SA 25/75 wt.% blends underwent microscopic phase separation, resulting in globular structures composed mainly of SF. X-ray diffraction indicated the amorphous nature of these blends, even after a treatment with ethanol that turned them insoluble in water. Thermal analyses of blends showed the peaks of degradation of pristine SF and SA shifted to intermediate temperatures. Water vapor permeability, swelling capacity and tensile strength of SF films could be enhanced by blending with SA. Cell viability remained between 90 and 100%, as indicated by in vitro cytotoxicity test. The SF/SA blend with self-assembled SF globules can be used to modulate structural and mechanical properties of the final material and may be used in designing high performance wound dressing. - Highlights: • Blend films of fibroin and alginate were prepared with microscopic phase separation; • Self-assembled globular microdomains were mainly composed by fibroin; • It was possible to obtain a film with better mechanical and physical properties; • Blend films of fibroin and alginate represent a novel material in biomaterials field.

  12. Blended working: for whom it may (not work.

    Directory of Open Access Journals (Sweden)

    Nico W Van Yperen

    Full Text Available Similarly to related developments such as blended learning and blended care, blended working is a pervasive and booming trend in modern societies. Blended working combines on-site and off-site working in an optimal way to improve workers' and organizations' outcomes. In this paper, we examine the degree to which workers feel that the two defining features of blended working (i.e., time-independent working and location-independent working enhance their own functioning in their jobs. Blended working, enabled through the continuing advance and improvement of high-tech ICT software, devices, and infrastructure, may be considered beneficial for workers' perceived effectiveness because it increases their job autonomy. However, because blended working may have downsides as well, it is important to know for whom blended working may (not work. As hypothesized, in a sample of 348 workers (51.7% women, representing a wide range of occupations and organizations, we found that the perceived personal effectiveness of blended working was contingent upon workers' psychological need strength. Specifically, the perceived effectiveness of both time-independent working and location-independent working was positively related to individuals' need for autonomy at work, and negatively related to their need for relatedness and need for structure at work.

  13. REVIEW: The Handbook Of Blended Learning: Global Perspectives, Local Designs

    OpenAIRE

    ATES, Reviewed By Alev

    2009-01-01

    Blended learning or blended e-learning sounds like a confusing term at first since it is relatively a new term for today’s instructors. However, Moore reports that it can be traced as far back as the 1920s which was called “supervised correspondence study”. For clarification of the term “blended learning” and informing the instructors about its common practices worldwide, the book provides readers a comprehensive resource about blended learning. It aims to raise awareness of adopting BL from ...

  14. Teaching European Studies: A Blended Learning Approach

    Directory of Open Access Journals (Sweden)

    Alina Christova

    2011-12-01

    Full Text Available This paper will be looking into the teaching method developed by the Institute for European Studies in Brussels, combining an e-learning tool- the E-modules- with face-to-face training sessions and webinars. The main aim is to analyse the three different components of this “blended learning” pedagogical approach, as well as the way they complement each other and to address a few of the challenges that have emerged from the experience of working with them so far. The E-modules are an e-learning platform that has been designed with the purpose of offering a structured and interactive way of learning how the European Union functions. The face-to-face training component currently takes the form of three days in-house seminars, covering in an intensive manner the most important areas of the curriculum. The lectures are held by a mix of academics and practitioners, hereby ensuring a balanced approach, in which theory and practice come together to facilitate the learning experience. The third element of the “blended learning” method is placed in-between online and face-to-face learning: interactive seminars and debates are held online, giving the participants the chance to deepen their knowledge in certain fields of interest and to discuss the content of the course with specialists and among themselves. The mixture of delivery and interaction methods was chosen in order to accommodate a large variety of target groups, ranging from students to professionals working with EU-related issues, with different backgrounds and geographical origins. One of the main challenges is to use each medium for the functionalities it is best designed for and to ensure that the various pieces of the pedagogical puzzle fit together perfectly, while allowing the learners the flexibility that had initially directed them towards “blended learning” instead of a classical classroom approach.

  15. Blending toward Competency. Early Patterns of Blended Learning and Competency-Based Education in New Hampshire

    Science.gov (United States)

    Freeland, Julia

    2014-01-01

    As the education field strives to differentiate and personalize learning to cater to each student, two related movements are gaining attention: competency-based education and blended learning. In competency-based models, students advance on the basis of mastery, rather than according to the traditional methods of counting progress in terms of time…

  16. Self-Determined Blended Learning: A Case Study of Blended Learning Design

    Science.gov (United States)

    De George-Walker, Linda; Keeffe, Mary

    2010-01-01

    Higher education has been actively encouraged to find more effective and flexible delivery models to provide all students with access to quality learning experiences yet also meet institutional imperatives for efficiency and accountability. Blended learning, commonly defined as an integration of traditional face-to-face and online approaches to…

  17. Line of sight stabilization - Sensor blending

    Science.gov (United States)

    Pettit, Christopher

    1991-10-01

    The paper examines a concept of blending inertial measuring sensors (IMS) which operate in different frequency ranges to produce an IMS sensor system that can measure base disturbances from dc to over 1000 Hz with minimum distortion. This information is them employed to point the line-of-sight (LOS) at a target with minimum jitter effects. Attention is given to a set of experimental results from this method involving the isolation of the LOS from the base motion of a space platform over a wide frequency range. The results reported, obtained from implementing the method on a two-body spacecraft simulator, include pointing stability and retargeting results. Results were encouraging.

  18. Electrospun cellulose nitrate and polycaprolactone blended nanofibers

    Science.gov (United States)

    Nartker, Steven; Hassan, Mohamed; Stogsdill, Michael

    2015-03-01

    Pure cellulose nitrate (CN) and blends of CN and polycaprolactone were electrospun to form nonwoven mats. Polymers were dissolved in a mixed solvent system of tetrahydrofuran and N,N-dimethylformamide. The concentrations were varied to obtain sub-micron and nanoscale fiber mats. Fiber mats were analyzed using scanning electron microscopy, contact angle analysis, Fourier transform infrared spectroscopy and thermal gravimetric analysis. The fiber morphology, surface chemistry and contact angle data show that these electrospun materials are suitable for applications including biosensing, biomedical and tissue engineering.

  19. The Health Impacts of Ethanol Blend Petrol

    Directory of Open Access Journals (Sweden)

    Rosemary Wood

    2011-02-01

    Full Text Available A measurement program designed to evaluate health impacts or benefits of using ethanol blend petrol examined exhaust and evaporative emissions from 21 vehicles representative of the current Australian light duty petrol (gasoline vehicle fleet using a composite urban emissions drive cycle. The fuels used were unleaded petrol (ULP, ULP blended with either 5% ethanol (E5 or 10% ethanol (E10. The resulting data were combined with inventory data for Sydney to determine the expected fleet emissions for different uptakes of ethanol blended fuel. Fleet ethanol compatibility was estimated to be 60% for 2006, and for the air quality modelling it was assumed that in 2011 over 95% of the fleet would be ethanol compatible. Secondary organic aerosol (SOA formation from ULP, E5 and E10 emissions was studied under controlled conditions by the use of a smog chamber. This was combined with meteorological data from Sydney for February 2004 and the emission data (both measured and inventory data to model pollutant concentrations in Sydney’s airshed for 2006 and 2011. These concentrations were combined with the population distribution to evaluate population exposure to the pollutant. There is a health benefit to the Sydney population arising from a move from ULP to ethanol blends in spark-ignition vehicles. Potential health cost savings for Urban Australia (Sydney, Melbourne, Brisbane and Perth are estimated to be A$39 million (in 2007 dollars for a 50% uptake (by ethanol compatible vehicles of E10 in 2006 and $42 million per annum for a 100% take up of E10 in 2011. Over 97% of the estimated health savings are due to reduced emissions of PM2.5 and consequent reduced impacts on mortality and morbidity (e.g., asthma, cardiovascular disease. Despite more petrol-driven vehicles predicted for 2011, the quantified health impact differential between ULP and ethanol fuelled vehicles drops from 2006 to 2011. This is because modern petrol vehicles, with lower emissions than

  20. Blended e-learning en universidades andaluzas

    OpenAIRE

    Tirado Morueta, Ramón; Pérez Rodríguez, María Amor; Aguaded Gómez, José Ignacio

    2011-01-01

    Conocer la implantación de la enseñanza virtual en el sistema universitario es hoy una prioridad básica en la investigación educativa para evaluar los nuevos procesos de enseñanza y aprendizaje que esta modalidad didáctica está generando. El ya llamado «blended e-learning» se ha ido implantando en las distintas universidades de todo el mundo con resultados muy variables. En este trabajo se presentan los resultados de un Proyecto de Investigación de Excelencia desarrollado en la...

  1. Blend Analysis of HATNet Transit Candidates

    Directory of Open Access Journals (Sweden)

    Bakos G.Á.

    2011-02-01

    Full Text Available Candidate transiting planet systems discovered by wide-field groundbased surveys must go through an intensive follow-up procedure to distinguish the true transiting planets from the much more common false positives. Especially pernicious are configurations of three or more stars which produce radial velocity and light curves that are similar to those of single stars transited by a planet. In this contribution we describe the methods used by the HATNet team to reject these blends, giving a few illustrative examples.

  2. BLENDED TECHNOLOGY IN LEARNING FOREIGN LANGUAGES

    Directory of Open Access Journals (Sweden)

    Natalia Alexandrovna Kameneva

    2013-11-01

    Full Text Available This article analyzes the use of information technologies in the context of a blended technology approach to learning foreign languages in higher education institutions. Distance learning tools can be categorized as being synchronous (webinar, video conferencing, case-technology, chat, ICQ, Skype, interactive whiteboards or asynchronous (blogs, forums, Twitter, video and audio podcasts, wikis, on-line testing. Sociological and psychological aspects of their application in the educational process are also considered.DOI: http://dx.doi.org/10.12731/2218-7405-2013-8-41

  3. From E-learning to Blended Learning

    DEFF Research Database (Denmark)

    Hansen, Line Skov; Hansen, Ole

    2013-01-01

    This paper presents the didactical considerations, theoretical approaches and first experiences with a cohesive school and kindergarten research-based development project in a Norwegian municipality. The project involves 41 schools and 70 kindergartens, inclusive all leaders and pedagogical staff....... The project uses a ?capacity building strategy where new practice and skills are built through pedagogical interventions mostly designed as courses based on blended learning with a dialogue oriented and practice related team-work as an important part. Through this work the team learns how to use a...

  4. Blended learning specialists in radiation protection

    International Nuclear Information System (INIS)

    In this paper, we present a blended learning Radiation Protection Technician through an approved degree from the Polytechnic University of Valencia, which covers the knowledge and skills of functions relating to operators and supervisors in various areas and skilled workers to be to perform their work in technical units or Radiation Protection Radiation Protection Services. The benefits of this work are those related to achieving quality training flexible and adapted to follow the check off the person conducting the course, adapted to internal and external training of the applicant companies.

  5. Initial retrieval sequence and blending strategy

    Energy Technology Data Exchange (ETDEWEB)

    Pemwell, D.L.; Grenard, C.E.

    1996-09-01

    This report documents the initial retrieval sequence and the methodology used to select it. Waste retrieval, storage, pretreatment and vitrification were modeled for candidate single-shell tank retrieval sequences. Performance of the sequences was measured by a set of metrics (for example,high-level waste glass volume, relative risk and schedule).Computer models were used to evaluate estimated glass volumes,process rates, retrieval dates, and blending strategy effects.The models were based on estimates of component inventories and concentrations, sludge wash factors and timing, retrieval annex limitations, etc.

  6. Blended learning within an undergraduate exercise physiology laboratory.

    Science.gov (United States)

    Elmer, Steven J; Carter, Kathryn R; Armga, Austin J; Carter, Jason R

    2016-03-01

    In physiological education, blended course formats (integration of face-to-face and online instruction) can facilitate increased student learning, performance, and satisfaction in classroom settings. There is limited evidence on the effectiveness of using blending course formats in laboratory settings. We evaluated the impact of blended learning on student performance and perceptions in an undergraduate exercise physiology laboratory. Using a randomized, crossover design, four laboratory topics were delivered in either a blended or traditional format. For blended laboratories, content was offloaded to self-paced video demonstrations (∼15 min). Laboratory section 1 (n = 16) completed blended laboratories for 1) neuromuscular power and 2) blood lactate, whereas section 2 (n = 17) completed blended laboratories for 1) maximal O2 consumption and 2) muscle electromyography. Both sections completed the same assignments (scored in a blinded manner using a standardized rubric) and practicum exams (evaluated by two independent investigators). Pre- and postcourse surveys were used to assess student perceptions. Most students (∼79%) watched videos for both blended laboratories. Assignment scores did not differ between blended and traditional laboratories (P = 0.62) or between sections (P = 0.91). Practicum scores did not differ between sections (both P > 0.05). At the end of the course, students' perceived value of the blended format increased (P < 0.01) and a greater percentage of students agreed that learning key foundational content through video demonstrations before class greatly enhanced their learning of course material compared with a preassigned reading (94% vs. 78%, P < 0.01). Blended exercise physiology laboratories provided an alternative method for delivering content that was favorably perceived by students and did not compromise student performance. PMID:26847259

  7. Morphology and enzymatic degradation of thermoplastic starch-polycaprolactone blends

    NARCIS (Netherlands)

    Vikman, M.; Hulleman, S.H.D.; Zee, van der M.; Myllarinen, P.; Feil, H.

    1999-01-01

    This study's aim was to evaluate the effect of processing conditions on the morphology and enzymatic degradation of 50/50 (w/w) thermoplastic starch-polycaprolactone blends. The blends, produced from native potato starch, glycerol, and polycaprolactone in a melt mixer using different mixing speeds a

  8. Blending MOOCs in Face-to-Face Teaching and Studies

    DEFF Research Database (Denmark)

    Nortvig, Anne-Mette; Gynther, Karsten; Gundersen, Peter Bukovica

    2016-01-01

    inspired by grounded theory. The paper will categorise former design experiments with MOOCs in blended settings, and, using design workshops and interviews with educators as our point of departure, we will sketch and discuss various models for blending MOOCs with face-to-face teaching and supporting...

  9. Student Engagement and Blended Learning: Making the Assessment Connection

    OpenAIRE

    Norman Vaughan

    2014-01-01

    There is an increased focus on student engagement and blended approaches to learning in higher education. This article demonstrates how collaborative learning applications and a blended approach to learning can be used to design and support assessment activities that increase levels of student engagement with course concepts, their peers, faculty and external experts, leading to increased student success and satisfaction.

  10. Teaching Human Development: A Case for Blended Learning

    Science.gov (United States)

    Cottle, Nathan R.; Glover, Rebecca J.

    2011-01-01

    This article makes a case for the use of blended learning in teaching human development as a means to encourage higher-order student learning outcomes. The authors review literature regarding the use and effectiveness of blended learning, discuss an illustrative example of a redesign of a human development course, present outcomes from a…

  11. A Blended Learning Approach to Course Design and Implementation

    Science.gov (United States)

    Hoic-Bozic, N.; Mornar, V.; Boticki, I.

    2009-01-01

    Blended learning has become an increasingly popular form of e-learning, and is particularly suitable to the process of transitioning towards e-learning from traditional forms of learning and teaching. This paper describes the use of the blended e-learning model, which is based on a mixture of collaborative learning, problem-based learning (PBL)…

  12. Design and Evaluation of Two Blended Learning Approaches: Lessons Learned

    Science.gov (United States)

    Cheung, Wing Sum; Hew, Khe Foon

    2011-01-01

    In this paper, we share two blended learning approaches used at the National Institute of Education in Singapore. We have been using these two approaches in the last twelve years in many courses ranging from the diploma to graduate programs. For the first blended learning approach, we integrated one asynchronous communication tool with face to…

  13. The Challenges of Blended Learning Using a Media Annotation Tool

    Science.gov (United States)

    Douglas, Kathy A.; Lang, Josephine; Colasante, Meg

    2014-01-01

    Blended learning has been evolving as an important approach to learning and teaching in tertiary education. This approach incorporates learning in both online and face-to-face modes and promotes deep learning by incorporating the best of both approaches. An innovation in blended learning is the use of an online media annotation tool (MAT) in…

  14. Challenges Facing Blended Learning in Higher Education in Asia

    Science.gov (United States)

    Tham, Raymond; Tham, Lesley

    2013-01-01

    This paper examines the current stage of development of blended learning in higher education in China, South Korea and Japan, with a comparison to the city state of Singapore. It is noted that blended learning and e-learning are introduced at institutes of higher learning in these countries with varying

  15. Blended Learning in Saudi Universities: Challenges and Perspectives

    Science.gov (United States)

    Alebaikan, Reem; Troudi, Salah

    2010-01-01

    This study is an attempt to investigate the nature of obstacles and challenges encountered at Saudi universities while implementing a blended learning approach. A literature review of blended learning rationale and designs, and the status of web-based education in Saudi higher education are demonstrated. Three main challenges of applying blended…

  16. A Blended Learning Model for Teaching Practice Course

    Science.gov (United States)

    Caner, Mustafa

    2010-01-01

    The aim of the present study is to introduce a blended learning environment and a model for pre-service teaching practice course in English Language Teacher Training Program at Anadolu University. It is supposed that providing a blended learning environment for teaching practice course would improve the practice and contribute to the professional…

  17. Students' Opinions on Facebook Supported Blended Learning Environment

    Science.gov (United States)

    Erdem, Mukaddes; Kibar, Pinar Nuhoglu

    2014-01-01

    The first purpose of this study was to determine students' opinions on blended learning and its implementation. The other purpose was to explore the students' opinions on Facebook integration into blended learning environment. The participants of this study were 40 undergraduate students in their fourth semester of the program.…

  18. Cyber Asynchronous versus Blended Cyber Approach in Distance English Learning

    Science.gov (United States)

    Ge, Zi-Gang

    2012-01-01

    This study aims to compare the single cyber asynchronous learning approach with the blended cyber learning approach in distance English education. Two classes of 70 students participated in this study, which lasted one semester of about four months, with one class using the blended approach for their English study and the other only using the…

  19. Collaborative Inquiry: Expert Analysis of Blended Learning in Higher Education

    Science.gov (United States)

    Wold, Kari

    2013-01-01

    This paper reports on findings of a university focus group exploring blended learning in higher education. It first describes the findings regarding the amorphous definition of blended learning as well as whether and how universities might engage in the practice. This paper then explains the administrative, instructor, and student variables that…

  20. Blended Learning at the Boundary: Designing a New Internship

    Science.gov (United States)

    Heckman, Robert; Østerlund, Carsten S.; Saltz, Jeffrey

    2015-01-01

    This paper explores how blended learning can enhance learning at the boundary between academia and industry, and make possible the design of a new kind of internship. Boundary theory proposes that socio-cultural discontinuities between different environments create opportunities for learning. Blended learning pedagogy makes it possible to make the…

  1. Blended Learning for College Students with English Reading Difficulties

    Science.gov (United States)

    Yang, Yu-Fen

    2012-01-01

    Most previous studies in blended learning simply involved on-site and online instruction without considering students' control of their own learning in these two different modalities. The purpose of this study was to investigate how college students with English reading difficulties integrate their conceptions of and approaches to blended learning…

  2. Encouraging User Participation in Blended Learning: Course Reorientation

    Science.gov (United States)

    Fairchild, Alea M.

    2015-01-01

    Blended learning, structured as a combination of traditional course instruction and additional supporting multimedia course content, can be used in higher education for a variety of reasons. In the case study that we examine, the introduction of blended learning was initiated three years ago with the purpose of creating more resources for…

  3. Student Outcomes and Design Elements in Blended Learning Courses

    Science.gov (United States)

    Newbury, Robert

    2013-01-01

    The concept of "blended learning" appears with increasing frequency in academic literature, published research and general discussion as the latest trend in pedagogy. Known also as "hybrid education" and "web-enhanced instruction", blended learning courses have been reported as the method of delivery for 80 to 90…

  4. Access Patterns of Online Materials in a Blended Course

    Science.gov (United States)

    Asarta, Carlos J.; Schmidt, James R.

    2013-01-01

    Patterns in student accesses of online materials and their effects upon student performance in a blended course are examined. Our blended course is an introductory business and economic statistics course where lectures are only available online while the traditional class period is used for complementary learning activities. Timing, volumes,…

  5. A Blended Mobile Learning Environment for Museum Learning

    Science.gov (United States)

    Hou, Huei-Tse; Wu, Sheng-Yi; Lin, Peng-Chun; Sung, Yao-Ting; Lin, Jhe-Wei; Chang, Kuo-En

    2014-01-01

    The use of mobile devices for informal learning has gained attention over recent years. Museum learning is also regarded as an important research topic in the field of informal learning. This study explored a blended mobile museum learning environment (BMMLE). Moreover, this study applied three blended museum learning modes: (a) the traditional…

  6. Critical crossover phenomena in compatible polymer blends studied with SANS

    DEFF Research Database (Denmark)

    Schwahn, D.; Janssen, S.; Willner, L.; Schmackers, T.; Springer, T.; Mortensen, K.; Takeno, H.; Hasegawa, H.; Jinnai, H.; Hashimoto, T.; Imai, M.

    1995-01-01

    Polymer blends show a much larger 3d-Ising regime, e.g. a much larger Ginzburg number Gi than predicted by the Ginzburg criterion. This discrepancy is supposed to be explained by the compressibility or the free volume of the blend. In this paper we present and discuss the Gi number of polymer ble...

  7. Polymer blend membranes for CO2 separation from natural gas

    Science.gov (United States)

    Mukhtar, H.; Mannan, H. A.; Minh, D.; Nasir, R.; Moshshim, D. F.; Murugesan, T.

    2016-06-01

    Polymeric membranes are dominantly used in industrial gas separation membrane processes. Enhancement in membranes permeability and/or selectivity is a key challenge faced by membrane researchers. The current work represents the effect of poyetherimide blending on separation performance of polysulfone membranes. Polysulfone/poyetherimide (PSF/PEI) blend flat sheet dense membranes were synthesized and tested for permeation analysis of CO2 and CH4 gases at 6, 8 and 10 bar pressure and 25oC temperature. Morphology and thermal properties of membranes were characterized by field emission scanning electron microscope (FESEM) and thermo gravimetric analysis (TGA) respectively. Blend membranes were dense and homogeneous as deduced from FESEM analysis. Thermal stability of synthesized blend membranes was maintained by blending with PEI as characterized by TGA results. Decrease in permeability of both gases was observed by the addition of PEI due to rigidity of PEI chains. Additionally, selectivity of synthesized blend membranes was enhanced by blending PEI and blend membranes show improved selectivity over pure PSF membrane. This new material has the capability to be used as gas separation membrane material.

  8. Thermal and X-ray characterization of polymer blends

    NARCIS (Netherlands)

    Oudhuis, Alida Anna Catherina Maria; Pennings, A.J

    1995-01-01

    In the last decade many studies have focused on phase behaviour of polymer blends. It determines the morphology and therefore to a large extend the mechanical properties. The most simple, well known and often used property to determine phase behaviour in polymer blends is the glass transition temper

  9. Radiation crosslinked block copolymer blends with improved impact resistance

    International Nuclear Information System (INIS)

    Polymer blends having high impact resistance after mechanical working are produced by blending together a non-elastomeric monovinylidene aromatic polymer such as polystyrene with an elastomeric copolymer, such as a block copolymer of styrene and butadiene, in the form of crosslinked, colloidal size particles

  10. An Experimental Analysis of Phoneme Blending and Segmenting Skills

    Science.gov (United States)

    Daly, Edward J., III; Johnson, Sarah; LeClair, Courtney

    2009-01-01

    In this 2-experiment study, experimental analyses of phoneme blending and segmenting skills were conducted with four-first grade students. Intraindividual analyses were conducted to identify the effects of classroom-based instruction on blending phonemes in Experiment 1. In Experiment 2, the effects of an individualized intervention for the…

  11. 27 CFR 24.214 - Spanish type blending sherry.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Spanish type blending... BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Other Than Standard Wine § 24.214 Spanish..., produced under this section, is designated “Spanish Type Blending Sherry.” Upon removal, the...

  12. Cycloolefin copolymer/polyethylene blends for medical applications

    Czech Academy of Sciences Publication Activity Database

    Kruliš, Zdeněk; Kotek, Jiří; Stará, Hana; Horák, Zdeněk; Hulejová, H.; Petrtýl, M.

    Palermo: University of Palermo, 2007. s. 72. [European Symposium on Polymer Blends /9./. 09.09.2007-12.09.2007, Palermo] R&D Projects: GA ČR GA106/06/0761 Institutional research plan: CEZ:AV0Z40500505 Keywords : skeletal replacement * blend * cycloolefin Subject RIV: CF - Physical ; Theoretical Chemistry

  13. Transport through track etched polymeric blend membrane

    Indian Academy of Sciences (India)

    Kamlendra Awasthi; Vaibhav Kulshreshtha; B Tripathi; N K Acharya; M Singh; Y K Vijay

    2006-06-01

    Polymer blends of polycarbonate (PC) and polysulphone (PSF) having thickness, 27 m, are prepared by solution cast method. The transport properties of pores in a blend membrane are examined. The pores were produced in this membrane by a track etching technique. For this purpose, a thin polymer membrane was penetrated by a single heavy ion of Ni7+ of 100 MeV, followed by preferential chemical etching of the ion track. Ion permeation measurements show that pores in polymeric membrane are charged or neutralized, which depends upon the variation in concentration of the solvent. The – curve at concentration, N/10, shows that the pores are negatively charged, whereas at concentration, N/20, the linear nature of – curve indicates that the pores approach towards neutralized state and on further concentration, N/40, the pores become fully neutralized, consequently the rectifier behaviour of pores has been omitted. The gas permeability of hydrogen and carbon dioxide of this membrane was measured with increasing etching time. The permeability was measured from both the sides. Permeability at the front was larger than the permeability at the back which shows asymmetric behaviour of membranes.

  14. Engineering thermal conductivity in polymer blends

    Science.gov (United States)

    Rashidi, Vahid; Coyle, Eleanor; Kieffer, John; Pipe, Kevin

    Weak inter-chain bonding in polymers is believed to be a bottleneck for both thermal conductivity and mechanical strength. Most polymers have low thermal conductivity (~0.1 W/mK), hindering their performance in applications for which thermal management is critical (e.g., electronics packaging). In this work, we use computational methods to study how hydrogen bonding between polymer chains as well as water content can be used to engineer thermal transport in bulk polymers. We examine how changes in the number of hydrogen bonds, chain elongation, density, and vibrational density of states correlate with changes in thermal conductivity for polymer blends composed of different relative constituent fractions. We also consider the effects of bond strength, tacticity, and polymer chain mass. For certain blend fractions, we observe large increases in thermal conductivity, and we analyze these increases in terms of modifications to chain chemistry (e.g., inter-chain bonding) and chain morphology (e.g., chain alignment and radius of gyration). We observe that increasing the number of hydrogen bonds in the system results in better packing as well as better chain alignment and elongation that contribute to enhanced thermal conductivity. The Air Force Office of Scientific Research, Grant No. FA9550-14-1-0010.

  15. Blending Online Asynchronous and Synchronous Learning

    Directory of Open Access Journals (Sweden)

    Lisa C. Yamagata-Lynch

    2014-04-01

    Full Text Available In this article I will share a qualitative self-study about a 15-week blended 100% online graduate level course facilitated through synchronous meetings on Blackboard Collaborate and asynchronous discussions on Blackboard. I taught the course at the University of Tennessee (UT during the spring 2012 semester and the course topic was online learning environments. The primary research question of this study was: How can the designer/instructor optimize learning experiences for students who are studying about online learning environments in a blended online course relying on both synchronous and asynchronous technologies? I relied on student reflections of course activities during the beginning, middle, and the end of the semester as the primary data source to obtain their insights regarding course experiences. Through the experiences involved in designing and teaching the course and engaging in this study I found that there is room in the instructional technology research community to address strategies for facilitating online synchronous learning that complement asynchronous learning. Synchronous online whole class meetings and well-structured small group meetings can help students feel a stronger sense of connection to their peers and instructor and stay engaged with course activities. In order to provide meaningful learning spaces in synchronous learning environments, the instructor/designer needs to balance the tension between embracing the flexibility that the online space affords to users and designing deliberate structures that will help them take advantage of the flexible space.

  16. Comprehensive characterization of chitosan/PEO/levan ternary blend films.

    Science.gov (United States)

    Bostan, Muge Sennaroglu; Mutlu, Esra Cansever; Kazak, Hande; Sinan Keskin, S; Oner, Ebru Toksoy; Eroglu, Mehmet S

    2014-02-15

    Ternary blend films of chitosan, PEO (300,000) and levan were prepared by solution casting method and their phase behavior, miscibility, thermal and mechanical properties as well as their surface energy and morphology were characterized by different techniques. FT-IR analyses of blend films indicated intermolecular hydrogen bonding between blend components. Thermal and XRD analysis showed that chitosan and levan suppressed the crystallinity of PEO up to nearly 25% of PEO content in the blend, which resulted in more amorphous film structures at higher PEO/(chitosan+levan) ratios. At more than 30% of PEO concentration, contact angle (CA) measurements showed a surface enrichment of PEO whereas at lower PEO concentrations, chitosan and levan were enriched on the surfaces leading to more amorphous and homogenous surfaces. This result was further confirmed by atomic force microscopy (AFM) images. Cell proliferation and viability assay established the high biocompatibility of the blend films. PMID:24507374

  17. Morphology and Mechanical Properties of (Epoxy/PVC Blend

    Directory of Open Access Journals (Sweden)

    Awham M. Hameed

    2015-09-01

    Full Text Available In this research, the morphology and mechanical properties of (Epoxy/PVC blend were investigated. (EP/PVC blend was prepared by manual mixing of epoxy resin with different weight ratios of (Poly vinyl chloride (PVC after dissolving it in cyclohexanon. Five sheets of polymer blends in wt% included (0%, 5%, 10%, 15% and 20% of PVC were prepared at room temperature. Tests were carried out to study some mechanical properties for these blends and compared with the properties of pure epoxy. The morphology of the prepared materials was examined to study the compatibility nature between the two polymers under work. It was found that the best ratio of addition is (20% of PVC. This percentage gave the highest value of tensile strength compared with other percentages of mixing for (EP/PVC blends.

  18. Positron annihilation lifetime study of interfaces in ternary polymer blends

    Science.gov (United States)

    Meghala, D.; Ramya, P.; Pasang, T.; Raj, J. M.; Ranganathaiah, C.; Williams, J. F.

    2013-06-01

    A new method based on positron lifetime spectroscopy is developed to characterize individual interfaces in ternary polymer blends and hence determine the composition dependent miscibility level. The method owes its origin to the Kirkwood-Risemann-Zimm (KRZ) model for the evaluation of the hydrodynamic interaction parameters (αij) which was used successfully for a binary blend with a single interface. The model was revised for the present work for ternary polymer blends to account for three interfaces. The efficacy of this method is shown for two ternary blends namely poly(styrene-co-acrylonitrile)/poly (ethylene-co-vinylacetate)/poly(vinyl chloride) (SAN/EVA/PVC) and polycaprolactone /poly(styrene-co-acrylonitrile)/poly(vinyl chloride) (PCL/SAN/PVC) at different compositions. An effective hydrodynamic interaction parameter, αeff, was introduced to predict the overall miscibility of ternary blends.

  19. A blend of Sodium Humate/SLES/Herbal Oils

    Directory of Open Access Journals (Sweden)

    Yeliz Akyiğit

    2013-08-01

    Full Text Available A blend of sodium humate (SH with anionic surfactants such as sodium lauryl ether sulfate (SLES was prepared by solution mixing at medium of herbal oils at 25, 50 and 75°C. Its miscibility studies were carried out by using physical techniques over an extended range of concentration and composition in buffer solution. In addition, to ascertain the state of miscibility of the blends, they were investigated by using UV-visible spectrophotometer and Fourier transform infrared (FTIR. These values revealed that the blend is miscible when the sodium humate content is more than %60 in the blend at all temperatures. There were no important differences in the characteristics of the blends at different temperatures.It was thought that the mechanism ofthe complex formation is realized by making strong intermolecular interaction like hydrogen bonds between the carbonyl groups in humic acid and hydroxyl groups in fatty acids.

  20. Photophysical studies of poly-isocyanopeptide based photovoltaic blends

    International Nuclear Information System (INIS)

    We report a photophysical study of photovoltaic blends containing perylene-substituted polyisocyanide (pery-PIC) materials, using time-correlated single photon counting and photo-induced absorption spectroscopy, and compare the key characteristics with analogous perylene-diimide (PDI) monomer blends with polythiophene- and polyfluorene-based conjugated polymers. Pery-PIC consists of semiconducting perylene units, which self-stack in a regular fashion around a rigid helical poly-isocyanopeptide backbone. In particular, the charged state lifetimes in pery-PIC blends are found to be of order tens of microseconds, this being typically less than half those of the perylene anion in the corresponding PDI blends. We consider the influence of photophysical factors on the superior photovoltaic device performance of the pery-PIC blends, relative to the corresponding PDI-based devices, in addition to the morphological effects described in earlier studies.

  1. Mechanical and thermal properties of physically-blended-plastic films

    International Nuclear Information System (INIS)

    Low density polyethylene (LDPE) and isotactic polypropylene (PP) blend were produced in film form and were characterized by a number of techniques such as wide-angle x-ray diffraction (WAXD), differential thermal analysis (DTA), scanning electron microscopy (SEM), and instron tensile testing. Results of WAXD and DTA showed conclusively that the two components in the blend are incompatible. SEM micrographs indicated that the 60/40 and 40/60 PP/PE blends show approximately fine homogeneous dispersion of the minor component into the matrix of the major component. The mechanical properties of the blend films improved with respect to the PE homo polymer. The improvement was more remarkable with the increase of the PP component in the blend. Results obtained in this work were explained in terms of crystallinity and the crystallite orientation. 28 refs., 29 figs., 5 tabs. (A.M.H.)

  2. Influence of coal blending on mineral transformation at high temperatures

    Institute of Scientific and Technical Information of China (English)

    BAI Jin; LI Wen; LI Chun-zhu; BAI Zong-qing; LI Bao-qing

    2009-01-01

    Transformation of mineral matter is important for coal utilization at high temperatures. This is especially true for blended coal. XRD and FTIR were employed together to study the transformation of mineral matter at high temperature in blended coals. It was found that the concentration of catalytic minerals, namely iron oxides, increases with an increasing ratio of Shenfu coal, which could improve coal gasification. The transformation characteristics of the minerals in blended coals are not exactly predictable from the blend ratio. This was proved by comparing the iron oxide content to the blending ratio. The results from FTIR are comparable with those from XRD. FTIR is an effective method for examining variation in mineral matter.

  3. RHEOLOGICAL BEHAVIOR OF POLYPHENYLENE SULFIDE/POLYAMIDE-66 BLENDS

    Institute of Scientific and Technical Information of China (English)

    HOU Canshu; LI Jihong; WANG Yinghan; CHEN Yongrong; WANG Ling

    1996-01-01

    Blends of polyphenylene sulfide (PPS) containing trace amounts of branching and/or cross-linking in chain and Polyamide-66 (PA-66) have been prepared by melt blending. The rheological behavior of PPS/PA-66 blends has been studied by means of capillary rheometer, and compared with PPS. The effects of shear rate, shear stress and temperature on the flow of PPS/PA-66 blends and PPS are discussed. The non-Newtonian indexes and the activation energies of viscous flow are obtained. The results show that the apparent viscosity of PPS/PA-66 blends is not sensitive to shear rate and stress, but decreases with the elevation of temperature. On the contrary, the apparent viscosity of the PPS decreases obviously with the increasing of shear rate and shear stress, but it is increased by the elevation of temperatue.

  4. Aging and mechanical properties of NR/BR blends

    Science.gov (United States)

    Chiu, Hsien-Tang; Tsai, Peir-An

    2006-02-01

    The mechanical properties and post-thermal aging properties of natural rubber (NR) and polybutadiene rubber (BR) blends at different blending ratios are investigated herein. The experimental results show that both tensile and tear strengths of NR/BR blends increase with increasing NR content. BR has a higher compression stiffness than NR. The deformation of BR is less than that of NR under the same load conditions. With regard to aging properties, both tensile stress and strain of NR/BR blends decrease after prolonged aging. In addition, the stress loss of BR is lower than that of NR, meaning that the aging resistance property of BR is superior to that of NR. Furthermore, accumulated thermal history has shifted the glass transition temperature (T g) of NR/BR blends toward lower temperatures while the loss tangent (tan δ) value increases with prolonged thermal aging.

  5. Blended Learning in Vocational Education: Teachers' Conceptions of Blended Learning and Their Approaches to Teaching and Design

    Science.gov (United States)

    Bliuc, Ana-Maria; Casey, Grant; Bachfischer, Agnieszka; Goodyear, Peter; Ellis, Robert A.

    2012-01-01

    This paper presents research exploring teachers' experiences of using blended learning in vocational education. Teachers involved in designing and teaching using blended learning from a major Australian vocational education provider participated in the study. They received open-ended questionnaires asking to describe their conceptions of blended…

  6. The Literature Landscape of Blended Learning in Higher Education: The Need for Better Understanding of Academic Blended Practice

    Science.gov (United States)

    Torrisi-Steele, Geraldine; Drew, Steve

    2013-01-01

    If we are to realise the potential of blended learning in higher education, then further research into academic practice and relevant academic development is essential. Our review of literature on blended learning in higher education reveals an interesting scholarship landscape which, when described in detail, pointedly directs attention to the…

  7. Rheology of miscible polymer blends with hydrogen bonding

    Science.gov (United States)

    Yang, Zhiyi

    Poly(4-vinylphenol) (PVPh) was blended with four different polymers: poly(vinyl methyl ether) (PVME), poly(vinyl acetate) (PVAc), poly(2-vinylpyridine) (P2VP), and poly(4-vinylpyridine) (P4VP) by solvent casting. The miscibility of these four PVPh-based blend systems was investigated using differential scanning calorimetry (DSC) and the composition-dependent glass transition temperature (Tg) was predicted by a thermodynamic theory. The hydrogen bonds between phenolic group in PVPh and ether group, carbonyl group or pyridine group was confirmed by Fourier transform infrared (FTIR) spectroscopy. The fraction of hydrogen bonds was calculated by the Coleman-Graf-Painter association model. Linear dynamic viscoelasticity of four PVPh-based miscible polymer blends with hydrogen bonding was investigated. Emphasis was placed on investigating how the linear dynamic viscoelasticity of miscible polymer blends with specific interaction might be different from that of miscible polymer blends without specific interaction. We have found that an application of time-temperature superposition (TTS) to the PVPh-based miscible blends with intermolecular hydrogen bonding is warranted even when the difference in the component glass transition temperatures is as large as about 200°C, while TTS fails for miscible polymer blends without specific interactions. On the basis of such an observation, we have concluded that hydrogen bonding suppressed concentration fluctuations in PVPh-based miscible blends. It has been found that both the intra-association (self-association) of the phenoxy hydroxyl groups in PVPh and inter-association (intermolecular interactions) between the constituent components have a profound influence on the frequency dependence of dynamic moduli in the terminal region of the PVPh-based miscible blend systems investigated. Hydrogenated functional polynorbornenes (HFPNBs) were synthesized and they were used to investigate the miscibility and rheology of HFPNB

  8. INOVASI PEMBELAJARAN AKUNTANSI BERBASIS BLENDED LEARNING

    Directory of Open Access Journals (Sweden)

    Lyna Latifah

    2016-02-01

    Full Text Available the accounting lectures have a big challengeb to improve the quality of graduates who are expected to have high knowledge and skill, to have good critical analysis and decision making. Thus: accounting lecturers are needed to improve their teaching and learning processes especially on learning design and assessment. Improving students knowledge and skill in accounting field can be created by using learning philosophy which makes students active and integrative in the class room. this articles discusses about the innovation of accounting learning with blended learning which collaborates cooperative learning and e-learning. Cooperative learning is a learning approach which emphasizes on structured behavior to cooperate in groups it can improve students interpersonal skill, cooperation, critical analysis and decision making. On the other hand, the application of cooperative learning needs more time so it can be solved by using computer with e-learning.

  9. Transactional distance in a blended learning environment

    Directory of Open Access Journals (Sweden)

    Jon Dron

    2004-12-01

    Full Text Available This paper presents a case study that describes and discusses the problems encountered during the design and implementation of a blended learning course, largely taught online through a web-based learning environment. Based on Moore's theory of transactional distance, the course was explicitly designed to have dialogue at its heart. However, the reality of systemic behaviours caused by delivering such a course within a group of conventional further and higher educational institutions has led to an entirely unanticipated reversion to structure, with unpleasant consequences for both quality and quantity of dialogue. The paper looks at some of the reasons for this drift, and suggests that some of the disappointing results (in particular in terms of the quality of the students' experience and associated poor retention can be attributed to the lack of dialogue, and consequent increase in transactional distance. It concludes with a description and evaluation of steps currently being taken to correct this behaviour.

  10. An Open Portal for Blended Learning

    DEFF Research Database (Denmark)

    Grønbæk, Kaj; Bouvin, Niels Olof; Petersen, Marianne Graves;

    2004-01-01

    , University of Aarhus has developed a CourseWeb system, which is an open configurable Web portal where the teachers are able to control courses and integrate facilities from third-part Web-based systems. At the same time students see the CourseWeb as an integrated access to study material and activities......The combination of traditional teaching and Web-based teaching, so called blended learning, is a challenge to the teachers as well as to the students. This shift in teaching demands an openness and flexibility from the technical platform which has not been found in the existing tools. Therefore....... This paper reflects on how the challenges with the creation of flexible Web-supported teaching are handled in two courses and how CourseWeb in the present and in the future is able to support this kind of teaching....

  11. Blended learning in the small animal clinic

    DEFF Research Database (Denmark)

    Langebæk, Rikke

    2011-01-01

    the implementation of these new teaching methods (e-learning and Skills Lab), teachers have ascertained a more satisfactory level of preparation, students that seem more focused and live-animal surgery that is conducted at a more ‘professional’ level than before. Finally, our research in this field shows......At the Department of Small Animal Clinical Sciences, Basic Surgical Skills are taught in groups of 30-35 students in the first year of the master program (4th year students). The eight day course is an example of ‘blended learning’ in which students use our e-learning-material (Step 1) to prepare......-lab (one day) and Step 4: live animal surgery (four days). The implementation of the Surgical Skills Lab as an introduction to training on real animals (cadavers and research pigs) seems to be a valuable, practical, economical and safe educational tool that is highly appreciated by students. Since...

  12. Blending in Nuclear Waste Tanks (Salt Disposition Initiative/Tank 50: Blending and Sludge Disturbance Study)

    International Nuclear Information System (INIS)

    The conclusions of this presentation are: (1) Designed, built, and fabricated the test equipment in 16 work days - (a) Six weeks to completion of initial 38 tests, (b) Total of 120 pilot scale tests, 30 CFD models, and 240 material property tests are complete, or in process. (2) 95% blending can be achieved in less than 12 hours - (a) Estimate from in-process test results, (b) Blending time at full scale will be checked from calculations in process, (c) Three to four days typically required to blend tank contents; (3) Recommendation to use one, non-rotating, pump instead of two for each of three tanks. (Pump cost per tank > 1 million dollars) - (a) Pump design parameters provided to SRR: nozzle velocity, nozzle diameter, nozzle angle from horizontal, and pump orientation with respect to the tank wall; and (4) Sludge disturbance was controlled at pilot scale - (a) Numerous models investigated, (b) Sludge disturbance at full scale will be established using CFD modeling and pilot scale test results.

  13. A study of coal-solid waste blend reactivity

    Directory of Open Access Journals (Sweden)

    Nayibe Guerrero

    2010-04-01

    Full Text Available The Flynn-Wall-Ozawa method was used for analysing coal-solid waste blend reactivity in an oxidising atmosphere. The presence of biomass strongly affected coal combustion kinetics when the blend contained more than 30% of it. Activation energy values (evaluated by different blends were 28.7495 kJ/mol for 0% biomass, 31.3915 kJ/mol for 30% biomass, 39.0365 kJ/mol for 50% biomass, 102.431 kJ/mol for 70% biomass and 107.8075 kJ/mol for 100% biomass; these values were close to those reported in the literature. First-order kinetics correlated the data ve-ry well for the 100% coal sample and the blend having 30% biomass and 70% coal. Eighth-order kinetics were more suitable for correlating the experimental data for the 70% biomass-30% coal blend and the 100% biomass sample. Combustion was done without previous pyrolysis of the blends; however segregation of phenomena could be appre-ciated. This seems to indicate that combustion and devolatilisation are independent processes which should be taken into account when building equipment using these kinds of blend.

  14. Quantification of rice bran oil in oil blends

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, R.; Sharma, H. K.; Sengar, G.

    2012-11-01

    Blends consisting of physically refined rice bran oil (PRBO): sunflower oil (SnF) and PRBO: safflower oil (SAF) in different proportions were analyzed for various physicochemical parameters. The quantification of pure rice bran oil in the blended oils was carried out using different methods including gas chromatographic, HPLC, ultrasonic velocity and methods based on physico-chemical parameters. The physicochemical parameters such as ultrasonic velocity, relative association and acoustic impedance at 2 MHz, iodine value, palmitic acid content and oryzanol content reflected significant changes with increased proportions of PRBO in the blended oils. These parameters were selected as dependent parameters and % PRBO proportion was selected as independent parameters. The study revealed that regression equations based on the oryzanol content, palmitic acid composition, ultrasonic velocity, relative association, acoustic impedance, and iodine value can be used for the quantification of rice bran oil in blended oils. The rice bran oil can easily be quantified in the blended oils based on the oryzanol content by HPLC even at a 1% level. The palmitic acid content in blended oils can also be used as an indicator to quantify rice bran oil at or above the 20% level in blended oils whereas the method based on ultrasonic velocity, acoustic impedance and relative association showed initial promise in the quantification of rice bran oil. (Author) 23 refs.

  15. Blending biodiesel in fishing boat fuels for improved fuel characteristics

    Directory of Open Access Journals (Sweden)

    Cherng-Yuan eLin

    2014-02-01

    Full Text Available Biodiesel is a renewable, clean, alternative energy source with advantages such as excellent lubricity, superior biodegradability and high combustion efficiency. Biodiesel is considered for mixing with fishing boat fuels to adjust their fuel characteristics so that toxic pollutants and greenhouse-effect gas emissions from such shipping might be reduced. The effects of blending fishing boat fuels A and B with various weight proportions of biodiesel are experimentally investigated in this study. The results show that biodiesel blending can significantly improve the inferior fuel properties of both fishing boat fuels and particularly fuel B. The flash points of both of these fuels increases significantly with the addition of biodiesel and thus enhances the safety of transporting and storing these blended fuels. The flash point of fishing boat fuel B even increases by 16% with 25 wt% biodiesel blending. The blending of biodiesel with no sulfur content is found to be one of the most effective ways to reduce the high sulfur content of fishing boat fuel, resulting in a reduction in the emission of sulfur oxides. The addition of only 25 wt% biodiesel decreased the sulfur content of the fishing boat fuel by 37%. The high kinematic viscosity of fishing boat fuel B was also observed to be reduced by 63% with the blending of just 25 wt% biodiesel. However, biodiesel blending caused a slight decrease in heating value around 1% to 4.5%.

  16. CURING AND MECHANICAL PROPERTIES OF CHLOROSULPHONATED POLYETHYLENE RUBBER BLEND

    Directory of Open Access Journals (Sweden)

    Jaroslava Budinski-Simendić

    2011-09-01

    Full Text Available In this paper, the curing and mechanical properties of two series of prepared blends, i.e., chlorosulphonated polyethylene (CSM/isobutylene-co-isoprene (IIR rubber blends and chlorosulphonated polyethylene (CSM/chlorinated isobutylene-co-isoprene (CIIR rubber blends were carried out. Blends were prepared using a two-roll mill at a temperature of 40-50 °C. The curing was assessed using a Monsanto oscillating disc rheometer R-100. The process of vulcanization accelerated sulfur of pure rubbers and their blends was carried out in an electrically heated laboratory hydraulic press under a pressure of about 4 MPa and 160 °C. The stress-strain experiments were performed using a tensile tester machine (Zwick 1425. Results indicate that the scorch time, ts2, and optimum cure time, tc90, increase with increasing CSM content in both blends. The value of modulus at 100 and 300% elongation and tensile strength increases with increasing CSM content, whereas elongation at break shows a decreasing trend. The enhancement in mechanical properties was supported by data of crosslink density in these samples obtained from swelling measurement and scanning electron microscopy studies of the rubber blends fractured surfaces

  17. Improved Mechanical Properties of Compatibilized Polypropylene/Polyamide-12 Blends

    Directory of Open Access Journals (Sweden)

    Nora Aranburu

    2015-01-01

    Full Text Available Compatibilized blends of polypropylene (PP and polyamide-12 (PA12 as a second component were obtained by direct injection molding having first added 20% maleic anhydride-modified copolymer (PP-g-MA to the PP, which produced partially grafted PP (gPP. A nucleating effect of the PA12 took place on the cooling crystallization of the gPP, and a second crystallization peak of the gPP appeared in the PA12-rich blends, indicating changes in the crystalline morphology. There was a slight drop in the PA12 crystallinity of the compatible blends, whereas the crystallinity of the gPP increased significantly in the PA12-rich blends. The overall reduction in the dispersed phase particle size together with the clear increase in ductility when gPP was used instead of PP proved that compatibilization occurred. Young’s modulus of the blends showed synergistic behavior. This is proposed to be both due to a change in the crystalline morphology of the blends on the one hand and, on the other, in the PA12-rich blends, to the clear increase in the crystallinity of the gPP phase, which may, in turn, have been responsible for the increase in its continuity and its contribution to the modulus.

  18. Comparison of Hybrid Blends for Solar Cell Application

    Directory of Open Access Journals (Sweden)

    Maria C. Lechmann

    2010-03-01

    Full Text Available In blended hybrid systems distinct micro- or nanostructured materials can be formed by phase separation. Network structures of particles or rods in a polymer matrix can be developed via self-assembly. We use this blending approach to compare active materials for application in solar cell devices. Blends were fabricated from either poly(hexylthiophene P3HT or poly(triphenylamine PTPA mixed with nanocrystalline TiO2 rods. In this manner, we compare two different hole conducting polymers in their performance in photovoltaic devices, while experimental conditions are kept identical. We find that the choice of solvent and photovoltaic characterization conducted in inert atmosphere is of importance for blends prepared from P3HT/TiO2 blends, but not for PTPA/TiO2 blends. Even though prepared with the same TiO2 rods, solar cells prepared from PTPA blends showed an enhanced efficiency when measured under ambient conditions. Furthermore, the PTPA/TiO2 showed higher long-term stability.

  19. Production of silk sericin/silk fibroin blend nanofibers

    Directory of Open Access Journals (Sweden)

    Zhang Xianhua

    2011-01-01

    Full Text Available Abstract Silk sericin (SS/silk fibroin (SF blend nanofibers have been produced by electrospinning in a binary SS/SF trifluoroacetic acid (TFA solution system, which was prepared by mixing 20 wt.% SS TFA solution and 10 wt.% SF TFA solution to give different compositions. The diameters of the SS/SF nanofibers ranged from 33 to 837 nm, and they showed a round cross section. The surface of the SS/SF nanofibers was smooth, and the fibers possessed a bead-free structure. The average diameters of the SS/SF (75/25, 50/50, and 25/75 blend nanofibers were much thicker than that of SS and SF nanofibers. The SS/SF (100/0, 75/25, and 50/50 blend nanofibers were easily dissolved in water, while the SS/SF (25/75 and 0/100 blend nanofibers could not be completely dissolved in water. The SS/SF blend nanofibers could not be completely dissolved in methanol. The SS/SF blend nanofibers were characterized by Fourier transform infrared (FTIR spectroscopy, differential scanning calorimetry, and differential thermal analysis. FTIR showed that the SS/SF blend nanofibers possessed a random coil conformation and ß-sheet structure.

  20. Production of silk sericin/silk fibroin blend nanofibers

    Science.gov (United States)

    Zhang, Xianhua; Tsukada, Masuhiro; Morikawa, Hideaki; Aojima, Kazuki; Zhang, Guangyu; Miura, Mikihiko

    2011-08-01

    Silk sericin (SS)/silk fibroin (SF) blend nanofibers have been produced by electrospinning in a binary SS/SF trifluoroacetic acid (TFA) solution system, which was prepared by mixing 20 wt.% SS TFA solution and 10 wt.% SF TFA solution to give different compositions. The diameters of the SS/SF nanofibers ranged from 33 to 837 nm, and they showed a round cross section. The surface of the SS/SF nanofibers was smooth, and the fibers possessed a bead-free structure. The average diameters of the SS/SF (75/25, 50/50, and 25/75) blend nanofibers were much thicker than that of SS and SF nanofibers. The SS/SF (100/0, 75/25, and 50/50) blend nanofibers were easily dissolved in water, while the SS/SF (25/75 and 0/100) blend nanofibers could not be completely dissolved in water. The SS/SF blend nanofibers could not be completely dissolved in methanol. The SS/SF blend nanofibers were characterized by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry, and differential thermal analysis. FTIR showed that the SS/SF blend nanofibers possessed a random coil conformation and ß-sheet structure.

  1. Analytical Characterization of Pure and Blended Watermelon (Citrullus lanatus oil: Impact of Blending on Oxidative Stability

    Directory of Open Access Journals (Sweden)

    Muhammad Waqar Azeem

    2015-06-01

    Full Text Available Analytical characterization of pure, blended watermelon (Citrulluslanatus oil and impact of blending on oxidative stability was investigated. Watermelon oil was added with mango (Mangiferaindica L. kernel oil at four different concentrations 5, 10, 15 and 20% (B1, B2, B3 and B4 and referenced with a control (100% watermelon oil. All the blends were stored in transparent PET bottles at ambient temperature (25-28oC for 3 months; storage stability was assessed at the interval of 1 month. Free fatty acid, unsaponifiable matter, saponification value, refractive index and iodine value of watermelon seed oil and mango kernel oil was 1.38%, 0.34%; 0.71%, 1.68%; 198, 193; 1.468, 1.457; 107.51, 54.62, respectively. The α tocopherol content of watermelon oil, mango kernel oil, B1, B2, B3 and B4 was 127.49, 205.44, 135.24, 144.52, 156.81 and 169.34 mg/kg. δ tocopherol in watermelon oil, mango kernel oil, B1, B2, B3 and B4 was 55.26, 34.81, 53.64, 51.27, 50.14 and 48.23 mg/kg. Concentration of linoleic acid decreased from 50.78% to 30.17% when 40% mango kernel oil was added to watermelon oil. Oleic acid increased from 22.89% in watermelon oil to 25.19%, 28.84% and 30.64% in B1, B2, B3 and B4. The increase in peroxide value of watermelon oil, B1, B2, B3 and B4 was 10.07, 9.56, 7.62, 5.17 and 2.87 (meqO2/kg in a time dependent manner. Induction period of pure watermelon oil was less than mango kernel oil and blends. These results suggest that chemical characteristics and oxidative stability of pure watermelon oil can be improved by blending with mango kernel oil.

  2. Compatibilized blends and value added products from leather industry waste

    Science.gov (United States)

    Sartore, Luciana; Di Landro, Luca

    2014-05-01

    Blends based on poly(ethylene-co-vinyl acetate) (EVA) and hydrolyzed proteins (IP), derived from waste products of the leather industry, have been obtained by reactive blending and their chemical physical properties as well as mechanical and rheological behavior were evaluated. The effect of vinyl acetate content and of transesterification agent addition to increase interaction between polymer and bio-based components were considered. These blends represent a new type of biodegradable material and resulted promising for industrial application in several fields such as packaging and agriculture as transplanting or mulching films with additional fertilizing action of IP.

  3. Canada's directory of ethanol-blended fuel retailers (December 1998)

    International Nuclear Information System (INIS)

    This publication serves as a directory of ethanol-blended gasoline retailers in Quebec, Ontario, Manitoba, Saskatchewan, Alberta, British Columbia, and the Yukon. The listings include the name and address of the retailer. The listing is organized by province and cities, beginning with the Yukon in the west and proceeding east to Quebec. A list of bulk purchase facilities of ethanol-blended fuels is also included. As of December 1998, there were a total of 929 retail outlets for ethanol blended gasoline in Canada

  4. Isothermal Melt Crystallization Kinetics of PP/organoclay Blends

    Directory of Open Access Journals (Sweden)

    Wang Kunyan

    2016-01-01

    Full Text Available Polystyrene (PP/organoclay (OMMT blends were prepared by co-rotating twin-screw extruder. The effects of OMMT on isothermal crystallization behaviors of blends was studied by differential scanning calorimetry (DSC. Using Avrami equation analysis the crystallization kinetics of materials. The analysis result shows that the OMMT act as effective nucleating agents, accelerating the crystallization of PP, then lead the rate of crystallization increased. Avrami exponent n is between 2.04~3.57, which indicating that PP/OMMT blends crystallization process might correspond to a two-dimensional or three-dimensional growth process. The activation enerigies for isotheraml crystallization were determined by the Arrhenius equation.

  5. A Blended Cement Containing Blast Furnace Slag and Phosphorous Slag

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Blended cement containing blast furnace slag(BFS) and phosphorous slag(PS) is a new kind of cement.The total content of blended materials could increase if two additives were used. Using the same admixtures, the properties of the blended cement with 70% additives could reach the standard of 525-grade slag cement according to GB.The strength of cement with 80% additives could reach the standard of 425-grade slag cement.The tests of strength, pore structure,hydration products,inhibiting alkali-aggregate reaction, resistance to sulfate corrosion of BFS-PSC were performed.

  6. Exciton and Hole-Transfer Dynamics in Polymer: Fullerene Blends

    Directory of Open Access Journals (Sweden)

    van Loosdrecht P. H. M.

    2013-03-01

    Full Text Available Ultrafast hole transfer dynamics from fullerene derivative to polymer in bulk heterojunction blends are studied with visible-pump - IR-probe spectroscopy. The hole transfer process is found to occur in 50/300 fs next to the interface, while a longer 15-ps time is attributed to exciton diffusion towards interface in PC71BM domains. High polaron generation efficiency in P3HT blends indicates excellent intercalation between the polymer and the fullerene even at highest PC71BM concentration thereby yielding a valuable information on the blend morphology.

  7. Phosphor blends for high-CRI fluorescent lamps

    Science.gov (United States)

    Setlur, Anant Achyut; Srivastava, Alok Mani; Comanzo, Holly Ann; Manivannan, Venkatesan; Beers, William Winder; Toth, Katalin; Balazs, Laszlo D.

    2008-06-24

    A phosphor blend comprises at least two phosphors each selected from one of the groups of phosphors that absorb UV electromagnetic radiation and emit in a region of visible light. The phosphor blend can be applied to a discharge gas radiation source to produce light sources having high color rendering index. A phosphor blend is advantageously includes the phosphor (Tb,Y,LuLa,Gd).sub.x(Al,Ga).sub.yO.sub.12:Ce.sup.3+, wherein x is in the range from about 2.8 to and including 3 and y is in the range from about 4 to and including 5.

  8. RIVER PROTECTION PROJECT MISSION ANALYSIS WASTE BLENDING STUDY

    Energy Technology Data Exchange (ETDEWEB)

    SHUFORD DH; STEGEN G

    2010-04-19

    Preliminary evaluation for blending Hanford site waste with the objective of minimizing the amount of high-level waste (HLW) glass volumes without major changes to the overall waste retrieval and processing sequences currently planned. The evaluation utilizes simplified spreadsheet models developed to allow screening type comparisons of blending options without the need to use the Hanford Tank Waste Operations Simulator (HTWOS) model. The blending scenarios evaluated are expected to increase tank farm operation costs due to increased waste transfers. Benefit would be derived from shorter operating time period for tank waste processing facilities, reduced onsite storage of immobilized HLW, and reduced offsite transportation and disposal costs for the immobilized HLW.

  9. Pivalolactone, 3. Reactive blending of polypivalolactone with polycarbonate

    OpenAIRE

    Tijsma, Edze Jan; Does, van der, A.J.W.; Bantjes, Adriaan; Vulic, Ivan; Werumeus Buning, Gerard Hidde

    1994-01-01

    The occurrence of interchange reactions during heating of polypivalolactone (PPVL) with three polymers and their influence on the blend properties were studied. Physical blends of PPVL and bisphenol-A polycarbonate (PC) were found to be immiscible. By heating of PPVL/PC blends in the melt at 280°C, in diphenyl ether at 260°C and in a twin-screw extruder (TSE) at 280°C partial formation of copolymers was observed, provided that tetrabutyl orthotitanate (TnBT) was added. After heating of equimo...

  10. TRANSESTERIFICATION IN POLYPHENYLSILSISQUIOXANE (PPSQ)/POLY ETHYLENE TEREPHTHALATE (PET) BLENDS

    Institute of Scientific and Technical Information of China (English)

    LI Guizhi; SHI Lianghe; YE Meiling; ZHAO Chuntian; XU Mao

    1995-01-01

    The chemical structure of copolymer formed in the transesterification of PPSQ/PET blends during melt-processing is deduced from the 1H-NMR spectra. The transesterification extent of this blend is interpreted by the changes of crystalline melting peak in DSC thermograms of the insoluble products containing unreacted PET and some block PPSQ segments. Effects of composition of blend ladderlike regularity of PPSQ on the reaction extent have also been discussed.Inclusion of some block PPSQ segments in PET has no influence on the crystalline morphology of PET.

  11. Viscometric and Rheological Behaviour of Chitosan-Hydrophilic Polymer Blends

    OpenAIRE

    R. K. Wanchoo; Thakur, Anupama; Sweta, A.

    2008-01-01

    Blends of chitosan with hydrophilic polymers were investigated for miscibility. Chitosan/poly (vinyl alcohol) (CS/PVA), chitosan/poly vinylpyrollidone (CS/PVP) and chitosan/poly (ethylene oxide) (CS/PEO) blends were prepared in dilute aqueous acetic acid ( = 1 %) and found to be miscible over the entire composition range by dilute solution viscosity and rheological measurements. The miscibility of blends by viscosity measurements at 25 ± 0.1 C was estimated on the basis of experimental and ...

  12. Blended e-learning Design: Discussion of Cultural Issues

    Directory of Open Access Journals (Sweden)

    Ahmed AL-Hunaiyyan

    2008-06-01

    Full Text Available Blended e-learning is becoming an educational issue especially with the new development of e-learning technology and globalization. Educators as the question: can we design these systems to accommodate different cultural groups and various learning strategies. This paper addresses some design issues when selecting a blended e-learning approach; it discusses some cultural elements that affect the design of blended e-learning. The paper also explores issues related to learning design, then emphasizes on the importance of cultural learning objects (CLO and its role in the design of multimedia-based e-learning systems.

  13. Controlling the Solidification of Organic Photovoltaic Blends with Nucleating Agents

    KAUST Repository

    Nekuda Malik, Jennifer A.

    2014-11-20

    Blending fullerenes with a donor polymer for the fabrication of organic solar cells often leads to at least partial vitrification of one, if not both, components. For prototypical poly(3-hexylthiophene):fullerene blend, we show that the addition of a commercial nucleating agent, di(3,4-dimethyl benzylidene)sorbitol, to such binary blends accelerates the crystallization of the donor, resulting in an increase in its degree of crystallinity in as-cast structures. This allows manipulation of the extent of intermixing/ phase separation of the donor and acceptor directly from solution, offering a tool to improve device characteristics such as power conversion efficiency.

  14. Image blending techniques and their application in underwater mosaicing

    CERN Document Server

    Prados, Ricard; Neumann, László

    2014-01-01

    This work proposes strategies and solutions to tackle the problem of building photo-mosaics of very large underwater optical surveys, presenting contributions to the image preprocessing, enhancing and blending steps, and resulting in an improved visual quality of the final photo-mosaic. The text opens with a comprehensive review of mosaicing and blending techniques, before proposing an approach for large scale underwater image mosaicing and blending. In the image preprocessing step, a depth dependent illumination compensation function is used to solve the non-uniform illumination appearance du

  15. Handbook for Handling, Storing, and Dispensing E85 and Other Ethanol-Gasoline Blends

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-03-02

    This document provides information on ethanol fuel properties, standards, codes, best practices, and equipment information for those who blend, distribute, store, sell, or use E15 (gasoline blended with 10.5 percent - 15 percent ethanol), E85 (marketing term for ethanol-gasoline blends containing 51 percent - 83 percent ethanol, depending on geography and season), and other ethanol blends.

  16. Handbook for Handling, Storing, and Dispensing E85 and Other Ethanol-Gasoline Blends

    Energy Technology Data Exchange (ETDEWEB)

    2016-03-01

    This document provides information on ethanol fuel properties, standards, codes, best practices, and equipment information for those who blend, distribute, store, sell, or use E15 (gasoline blended with 10.5 percent - 15 percent ethanol), E85 (marketing term for ethanol-gasoline blends containing 51 percent - 83 percent ethanol, depending on geography and season), and other ethanol blends.

  17. A systematic methodology for design of tailor-made blended products

    DEFF Research Database (Denmark)

    Yunus, Nor Alafiza Binti; Gernaey, Krist; Woodley, John;

    2014-01-01

    A systematic methodology for design of tailor-made blended products has been developed. In tailor-made blended products, one identifies the product needs and matches them by blending different chemicals. The systematic methodology has four main tasks. First, the design problem is defined: the pro...... methodology is highlighted through two case studies involving gasoline blends and lubricant base oils....

  18. Conversion and Blending Facility highly enriched uranium to low enriched uranium as metal. Revision 1

    International Nuclear Information System (INIS)

    The mission of this Conversion and Blending Facility (CBF) will be to blend surplus HEU metal and alloy with depleted uranium metal to produce an LEU product. The primary emphasis of this blending operation will be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. The blended LEU will be produced as a waste suitable for storage or disposal

  19. Investigation on thermal, mechanical and morphological properties of epoxy/UHWPE blends

    OpenAIRE

    Shahryar Pashaei; , Siddaramaiah; Akheel Ahmed Syed; Maziar Mansouji Avval

    2010-01-01

    Epoxy/ultrahigh molecular weight polyethylene (UHMWPE) blends have been prepared by in-situ polymerization method. The effects of UHMWPE from 2.5 wt % to 10 wt % on the tensile properties of blends have been studied. Tensile properties of blends are characterized and were shown that content 10% UHMWPE was effected on performance of polymer blends significantly. Thermal characteristics of the polymer blends were determined by using differential scanning calorimetry (DSC) and thermogravimetric ...

  20. Thermal Analysis (Differential Scanning Calorimetry And Thermogravimetric Analysis) Of SEBS Blends For Injection Molding

    OpenAIRE

    Juárez Varón, David; Ferrándiz Bou, Santiago; Peydro Rasero, Miguel Ángel; Sánchez Caballero, Samuel

    2013-01-01

    Thermal analysis (DSC: Differential Scanning Calorimetry and TGA: Thermogravimetric Analysis) of SEBS blends have been studied in this paper. SEBS blends were made using two transparent SEBS commercial grades with extreme hardness values. The first thermal property determined in SEBS blends was the evaluation of the thermal degradation at high temperatures (DSC). Another thermal property of the SEBS blends consists in knowing the degradation process of the blend (TGA). It should be emphasi...

  1. Modeling terminal ballistics using blending-type spline surfaces

    Science.gov (United States)

    Pedersen, Aleksander; Bratlie, Jostein; Dalmo, Rune

    2014-12-01

    We explore using GERBS, a blending-type spline construction, to represent deform able thin-plates and model terminal ballistics. Strategies to construct geometry for different scenarios of terminal ballistics are proposed.

  2. Effects of the Biodegradation on Biodegradable Polymer Blends and Polypropylene

    Science.gov (United States)

    Pereira, R. C. T.; Franchetti, S. M. M.; Agnelli, J. A. M.; Mattoso, L. H. C.

    2008-08-01

    The large use of plastics in the world generates a large amount of waste which persists around 200 years in the environment. To minimize this effect is important to search some new polymer materials: the blends of biodegradable polymers with synthetic polymers. It is a large area that needs an intensive research to investigate the blends properties and its behavior face to the different treatments to aim at the biodegradation. The blends used in this work are: some biodegradable polymers such as: poly(hydroxybutyrate) (PHB) and poly(ɛ-polycaprolactone) (PCL) with a synthetic polymer, polypropylene (PP), in lower concentration. These blends were prepared using an internal mixer (Torque Rheometer), and pressed. These films were submitted to fungus biotreatment. The films analyses will be carried out by Fourier Transform Infrared (FTIR), UV-Vis absorption (UV-Vis), Scanning Electronic Microscopy (SEM), DSC and TGA.

  3. Tensile deformation mechanisms of ABS/PMMA/EMA blends

    Science.gov (United States)

    Wang, S. H.; Gao, J.; Lin, S. X.; Zhang, P.; Huang, J.; Xu, L. L.

    2014-08-01

    The tensile deformation mechanisms of acrylonitrile - butadiene - styrene (ABS) / polymethyl methacrylate (PMMA) blends toughened by ethylene methacrylate (EMA) copolymer was investigated by analysing the fracture morphology. ABS/PMMA was blended with EMA copolymer by melt mixing technique using co-rotating twin extruder. Tensile tests show that the elongation at break of ABS/PMMA blends can be efficiently improved with the increase in EMA content. Fracture morphology of ABS/PMMA/EMA blends reveals that the material yield induced by hollowing-out of EMA particles and its propagation into yield zone is the main toughening mechanism. Moreover, the appearance that EMA particles in the central area are given priority to hollowing-out may be related to the skin-core structure of the injection moulded parts caused by the different cooling rate between surface and inside in the process of injection moulding.

  4. SST, Blended, 0.1 degrees, Global, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA OceanWatch provides a blended sea surface temperature (SST) products derived from both microwave and infrared sensors carried on multiple platforms. The...

  5. Feedback model to support designers of blended learning courses

    NARCIS (Netherlands)

    Hummel, Hans

    2006-01-01

    Hummel, H. G. K. (2006, December). Feedback model to support designers of blended learning courses. International Review of Open and Distance Learning [Online], 7(3). Available: http://www.irrodl.org/index.php/irrodl/article/view/379/748

  6. Influence of compatibilizer on blends degradation during processing

    Directory of Open Access Journals (Sweden)

    Walter R. Waldman

    2013-01-01

    Full Text Available The thermomechanical degradation of blends made from polypropylene and polystyrene, with or without compatibilizer, was studied using an internal mixer coupled to a torque rheometer. The blends processed without compatibilizer presented regular and expected results regarding torque reduction, with evidence of chain scission. The blends processed with the block copolymer of styrene and butadiene, SBS, as a compatibilizer presented unchanged or less reduced variation on torque values during processing. The extraction of stabilizers from the compatibilizer before processing did not affect the results. The compatibilizer concentration in the blends was varied, with its influence still being observed in concentrations as low as 0.03 parts per hundred. Similar results were obtained in an experiment comparing the performance of a primary commercial anti-oxidant, Irganox 1076, and the compatibilizer SBS. Therefore, the compatibilizer can be considered as a processing aid agent with positive influence on avoiding thermomechanical degradation.

  7. Enhancing the blended learning experience of Calculus I students

    Directory of Open Access Journals (Sweden)

    A. Al-Ghassani

    2015-08-01

    Full Text Available Blended Learning showed in the last two decades to be one of the effective ways in education and training. We illustrate our initiative experience with blended learning in the course Calculus I. The main goals we want to achieve are improving students understanding of the course concepts, increasing the level of uniformity in this multi-sections course and enhancing students blended learning experience online and offline. Consequently, this affects positively students' academic performance. We describe and discuss the results that we achieved and the challenges we encountered in view of the initiative aims and goals. The blended learning delivery methods were through Learning Management System (LMS as the online medium and through new offline activities inside and outside the classroom. The LMS we used is Moodle. We designed the resources and activities to cater for the learners different needs. The offline activities were chosen and designed to strengthen the weakness in students study skills based in our experience.

  8. Characterization of Fibers Produced from Blends of Polybutylene and Polypropylene

    Directory of Open Access Journals (Sweden)

    Robert L. Shambaugh, Ph.D

    2007-11-01

    Full Text Available Blends of polybutylene (PB-1 and polypropylene were used to produce fibers at spinning speeds of 800-2100 m/min. Concentrations ranged from 0% PP to 100% PP. The stress-strain behavior of the resultant fibers was examined, and the fibers were analyzed for crystallinity via DSC (differential scanning calorimetry. Fibers produced from blends of PB-1/PP show mechanical properties that are in between the properties of the pure polymers. The tensile strength of 50% PB-1 fibers is comparable to the tensile strength of pure PP fibers. Fibers produced from blend compositions of 25 and 75% have higher tensile strengths than pure PP fibers, although these blend compositions have lower tensile strengths than pure PB fibers.

  9. Critical crossover phenomena in compatible polymer blends studied with SANS

    DEFF Research Database (Denmark)

    Schwahn, D.; Janssen, S.; Willner, L.;

    1995-01-01

    Polymer blends show a much larger 3d-Ising regime, e.g. a much larger Ginzburg number Gi than predicted by the Ginzburg criterion. This discrepancy is supposed to be explained by the compressibility or the free volume of the blend. In this paper we present and discuss the Gi number of polymer...... monomeric microstructure and on pressure. This clearly shows that Gi is not a universal function. The observed strong decrease of Gi with pressure is a clear experimental proof that the critical crossover behaviour in polymer blends is indeed strongly influenced by the compressibility or free volume of the...... blends, different in chemistry, molecular weight, and microstructure. One sample was also studied at a different pressure. Gi was determined by describing the susceptibility obtained from SANS with the crossover function from Belyakov et al. The essential results are that Gi depends sensitively on...

  10. Chemical interesterification of blends with palm stearin and patawa oil.

    Science.gov (United States)

    Oliveira, Pedro D; Rodrigues, Antonio M C; Bezerra, Carolina V; Silva, Luiza H M

    2017-01-15

    The present study sought to develop lipid bases from blends between patawa oil and palm stearin. These blends were analyzed before and after the chemical interesterification process for their fatty acid and triacylglycerol composition, free fatty acid (FFA) content, peroxide index, thermal properties, melting point, consistency, and solid fat content (SFC). Blends with unsaturated fatty acid contents between 60 and 70% were obtained, with a good ratio between saturated and unsaturated fatty acids, which indicates a healthy content of fatty acids. Variations in the triacylglycerol contents and melting and crystallization thermograms evidenced the reaction. The blend with 50% stearin and 50% patawa oil showed the best results after the chemical interesterification reaction regarding the possible application in fatty products for its appropriate melting point, SFC similar to that of soft table margarines, plastic and spreadable consistency at refrigeration temperature, thus combining physical and nutritional properties desirable for the food industry. PMID:27542488

  11. [Konjac glucomannan-collagen -chitosan blend films (I)].

    Science.gov (United States)

    Wang, Bi; Wang, Kunyu; Dan, Weihu; Zhang, Tingyou; Ye, Yong

    2006-02-01

    Konjac glucomannan-collagen-chitosan blend films were prepared successfully by the solvent-casting method and were characterized by FT-IR,X-ray diffraction, SEM and optical transmittance. Moreover, tensile strength, breaking extension, water absorption, water vapor permeation coefficients, adsorbability and penetrating rates were measured. The results indicated that some strong interaction and good compatibility existed among Konjac glucomannan /collagen and chitosan in the blend films. Some properties of the KCCS films were improved markedly in comparison with binary blend films or Konjac glucomannan, collagen and chitosan film. The results of culturing vessel endothelial cells on CKCS-5 film showed that the blend films have good cell compatibility which indicates the potential for a scalfold material in tissue engineering. PMID:16532821

  12. Interacting Blends of Novel Unsaturated Polyester Amide Resin with Styrene

    OpenAIRE

    Hasmukh S. Patel; Panchal, Kumar K.

    2004-01-01

    Novel unsaturated poly (ester-amide) resins (UPEAs) were prepared by the reaction between an epoxy resin, namely diglycidyl ether of bisphenol–A (DGEBA) and unsaturated aliphatic bisamic acids using a base catalyst. These UPEAs were then blended with a vinyl monomer namely, Styrene (STY.) to produce a homogeneous resin syrup. The curing of these UPEAs-STY. resin blends was carried out by using benzoyl peroxide (BPO) as a catalyst and was monitored by using a differential scanning calorimeter ...

  13. Becoming Blended. A Case Study in Teacher Identity

    OpenAIRE

    Rentería, Victoria

    2014-01-01

    This case-study explores the identities of two teachers in the English Blended Program of a Mexican University during a four month period. The aim is to discover how agency creates different kinds of impacts on teacher's identity in the context of a blended program. Through an interpretive and sociocultural perspective an analysis was conducted by examining data gathered from face-to-face class observations, teacher's Moodle pages, teacher's journals and interviews, as well as questionnaires ...

  14. Assessing the impact of blended learning on student performance

    OpenAIRE

    Do Won Kwak; Flavio Menezes; Carl Sherwood

    2013-01-01

    This paper assesses quantitatively the impact on student performance of a blended learning experiment within a large undergraduate first year course in statistics for business and economics students. We employ a differences- in-difference econometric approach, which controls for differences in student characteristics and course delivery method, to evaluate the impact of blended learning on student performance. Although students in the course manifest a preference for live lectures over online...

  15. Agarose and methylcellulose hydrogel blends for nerve regeneration applications

    Science.gov (United States)

    Martin, Benton C.; Minner, Eric J.; Wiseman, Sherri L.; Klank, Rebecca L.; Gilbert, Ryan J.

    2008-06-01

    Trauma sustained to the central nervous system is a debilitating problem for thousands of people worldwide. Neuronal regeneration within the central nervous system is hindered by several factors, making a multi-faceted approach necessary. Two factors contributing to injury are the irregular geometry of injured sites and the absence of tissue to hold potential nerve guides and drug therapies. Biocompatible hydrogels, injectable at room temperature, that rapidly solidify at physiological temperatures (37 °C) are beneficial materials that could hold nerve guidance channels in place and be loaded with therapeutic agents to aid wound healing. Our studies have shown that thermoreversible methylcellulose can be combined with agarose to create hydrogel blends that accommodate these properties. Three separate novel hydrogel blends were created by mixing methylcellulose with one of the three different agaroses. Gelation time tests show that the blends solidify at a faster rate than base methylcellulose at 37 °C. Rheological data showed that the elastic modulus of the hydrogel blends rapidly increases at 37 °C. Culturing experiments reveal that the morphology of dissociated dorsal root ganglion neurons was not altered when the hydrogels were placed onto the cells. The different blends were further assessed using dissolution tests, pore size evaluations using scanning electron microscopy and measuring the force required for injection. This research demonstrates that blends of agarose and methylcellulose solidify much more quickly than plain methylcellulose, while solidifying at physiological temperatures where agarose cannot. These hydrogel blends, which solidify at physiological temperatures naturally, do not require ultraviolet light or synthetic chemical cross linkers to facilitate solidification. Thus, these hydrogel blends have potential use in delivering therapeutics and holding scaffolding in place within the nervous system.

  16. THE SUCCESSFUL INCORPORATION OF BLENDED LEARNING INTO THE LANGUAGE CURRICULUM

    OpenAIRE

    Simpson, Adam J.

    2016-01-01

    A phenomenon attracting increasing attention in language curricula is the infusion of technology into traditional, face-to-face (FTF) language instruction. Nevertheless, computer-assisted language learning (CALL) still lacks a body of qualitative research on the notion of blended learning (BL). Particularly, what is lacking is information regarding teachers' perceptions of blended learning, or the roles they are expected to play in such mixed environments; without an understanding of these is...

  17. Preparation and characterization of silk fibroin/HPMC blend film

    Energy Technology Data Exchange (ETDEWEB)

    Shetty, G. Rajesha [Department of Physics, Govt. First Grade College Hiriadka, Udupi - 576113 (India); Kumar, R. Madhu; Rao, B. Lakshmeesha; Asha, S.; Sangappa, E-mail: syhalabhavi@yahoo.co.in [Department of Studies in Physics, Mangalore University, Mangalagangotri, Mangalore - 574199 (India)

    2015-06-24

    In this work, the structural and mechanical stability of silk fibroin/Hydroxypropylmethyl cellulose (SF-HPMC) blend films were characterized by X-ray diffraction (XRD) and Universal Testing Machine (UTM). The results indicate that with the introduction of HPMC, the interactions between SF and HPMC results in improved crystallite size and increase in mechanical properties. The blend film obtained is more flexible compared to pure SF film.

  18. General Blending Models for Mixture Experiments: Design and Analysis

    OpenAIRE

    Brown, Liam John

    2014-01-01

    It is felt the position of the Scheffé polynomials as the primary, or sometimes sole recourse for practitioners of mixture experiments leads to a lack of enquiry regarding the type of blending behaviour that is used to describe the response and that this could be detrimental to achieving experimental objectives. Consequently, a new class of models and new experimental designs are proposed allowing a more thorough exploration of the experimental region with respect to different blending behavi...

  19. A blend of Sodium Humate/SLES/Herbal Oils

    OpenAIRE

    Yeliz Akyiğit; Mümin Dizman; Ahmet Tutar

    2013-01-01

    A blend of sodium humate (SH) with anionic surfactants such as sodium lauryl ether sulfate (SLES) was prepared by solution mixing at medium of herbal oils at 25, 50 and 75°C. Its miscibility studies were carried out by using physical techniques over an extended range of concentration and composition in buffer solution. In addition, to ascertain the state of miscibility of the blends, they were investigated by using UV-visible spectrophotometer and Fourier transform infrared (FTIR). These valu...

  20. Operating Systems with Blended Extreme Apprenticeship: What Are Students’ Perceptions?

    OpenAIRE

    Gabriella Dodero; Rosella Gennari

    2015-01-01

    Extreme apprenticeship, an emerging learning methodology, has been used in a blended fashion for teaching a technical subject: bash scripting for operating systems. Online learning was first supported with the Moodle platform, and then enhanced with playful videos. How did students perceive learning in such a manner? This paper reports on the design of the blended learning experience for operating systems, and then focusses on the evaluation of learners’ perceptions of it.

  1. Implementing Blended Learning Technology in Higher Professional Education

    OpenAIRE

    Matukhin, Dmitriy Leonidovich; Zhitkova, Elena

    2015-01-01

    The paper dwells on the learning outcomes of experimental implementing of blended learning technology in the English language teaching to engineering students of the Tomsk Polytechnic University. The aim of blended learning application is to enhance efficiency of the learning process by means of up-to-date highly-technological means of instruction. The author identified the level of information competency of engineering students, analyzed psychological readiness of engineering students to han...

  2. Study of Blended Learning Process in Education Context

    OpenAIRE

    Asif Irshad Khan; Noor-ul-Qayyum; Mahaboob Sharief Shaik; Abdullah Maresh Ali; Ch.Vijaya Bebi

    2012-01-01

    Education is one of the areas that are experiencing phenomenal changes as a result of the advancement and use of information technology. Mobile and e-learning are already facilitating the teaching and learning experience with the use of latest channels and technologies. Blended learning is a potential outcome of advanced technology based learning system. The charm of blended learning approach lies in the adaptation of technology aided learning methods in addition to the existing traditional b...

  3. A Blended Learning Model For Teaching Practice Course

    OpenAIRE

    Mustafa CANER

    2010-01-01

    The aim of the present study is to introduce a blended learning environment and a model for pre-service teaching practice course in English Language Teacher Training Program at Anadolu University. It is supposed that providing a blended learning environment for teaching practice course would improve the practice and contribute to the professional growth of pre-service teachers. Since it will increase the contact hours among students and university supervisors and facilitate peer feedback amon...

  4. 有关blended learning的几个问题

    Institute of Scientific and Technical Information of China (English)

    万士全

    2005-01-01

    本文主要依据国内外的一些关于"Blended Learning"的文献资料,概括介绍一些Blended Learning的基本概念、实行策略以及媒体选择等问题,并进一步探讨其对教育教学活动的影响

  5. A blended learning concept for guided self-instruction

    OpenAIRE

    Schreurs, Jeanne; Al-Zoubi, A.Y.

    2007-01-01

    Learning models are evolving from instructor centred, over learner centred to learning team-centred approach. learning is evolving to guide individual and collaborative self-paced web-based learning. In this paper, a supervised and guided individual self-paced web-based learning concept including collaborative learning in a virtual class is adapted. Blended learning is set forward as the solution. We focus on the requirements of the blended learning concept to be a good solution for this lear...

  6. Use of Blended Approach in the Learning of Electromagnetic Induction

    OpenAIRE

    Chew, Charles; Wee, Loo Kang

    2015-01-01

    This paper traces the importance of pedagogical content knowledge in the digital age to prepare today students for the 21st century. It highlights the need for ICT-based pedagogical models that are grounded in both the learning theories of constructivism and connectivism. One such suitable ICT-based pedagogical model is the TSOI Hybrid Learning Model. By means of a physics blended learning exemplar based on the TSOI Hybrid Learning Model, this paper argues for the use of blended learning appr...

  7. Investigation into the Possibilities of Using Fuel Blends in Locomotives

    Directory of Open Access Journals (Sweden)

    Dmitrij Kolesnikov

    2012-11-01

    Full Text Available The paper examines the structural features and properties of fuel blends and fuel emulsions, presents an overview of formulas obtained getting stable emulsions and analyses the results of experimental studies on preparing mixtures made of different quantities of diesel and various additives considering certain parameters. The article discusses the dependence of the size of resulting particles of water in the emulsion and describes an impact of various additives on the size of particles and time for blend delamination.

  8. Preparation and characterization of thermoplastic starch/zein blends

    OpenAIRE

    Elisângela Corradini; Antonio José Felix de Carvalho; Antonio Aprigio da Silva Curvelo; José Augusto Marcondes Agnelli; Luiz Henrique Capparelli Mattoso

    2007-01-01

    Blends of starch and zein plasticized with glycerol were prepared by melting processing in an intensive batch mixer connected to a torque rheometer at 160 °C. The resulting mixtures were compression molded and then characterized by scanning electron microscopy, differential scanning calorimetry, wide-angle X ray diffraction and water-absorption experiments. The blends were immiscible, showing two distinct phases of starch and zein. The water uptake at equilibrium and its diffusion coeffic...

  9. Teacher Adoption of Web-based Learning in Blended Environment

    OpenAIRE

    Fung, HNH; Yuen, AHK

    2006-01-01

    Because of the significant benefits to be gained from Internet technology, many educational institutions have brought in online learning management systems to their traditional classroom courses. The emergence of blended instruction allows teachers to integrate the advantages of face-to-face classroom interactions with positive attributes of distance learning. Nevertheless, the value of the blended approach relies heavily on the teachers’ adoption of the add-on platform. In view of the fact t...

  10. The characterization of novel biodegradable blends based on polyhydroxybutyrate

    OpenAIRE

    Pankova, Yulia; Shchegolikhin, Alexandr; lordanskii, Alexey; Zhulkina, Anna; Ol'khov, Anatoliy; Zaikov, Gennady

    2011-01-01

    The present paper focuses on the study of novel blends based on poly(3-hydroxybutyrate) (PHB) and polymers with different hydrophilicity (LDPE and PA). Polymer blends were produced from five ratios of PHB/LDPE in order to regulate the resistance to hydrolysis or (bio)degradation through the control of water permeability. The relation between the water transport and morphology (TEM data) shows the impact of polymer component ratio on the regulating water flux in a hydrophobic matrix. To elucid...

  11. Chemical and Enzymatic Hydrolysis of Polyurethane/Polylactide Blends

    OpenAIRE

    Joanna Brzeska; Aleksandra Heimowska; Wanda Sikorska; Lidia Jasińska-Walc; Marek Kowalczuk; Maria Rutkowska

    2015-01-01

    Polyether-esterurethanes containing synthetic poly[(R,S)-3-hydroxybutyrate] (R,S-PHB) and polyoxytetramethylenediol in soft segments and polyesterurethanes with poly(ε-caprolactone) and poly[(R,S)-3-hydroxybutyrate] were blended with poly([D,L]-lactide) (PLA). The products were tested in terms of their oil and water absorption. Oil sorption tests of polyether-esterurethane revealed their higher response in comparison to polyesterurethanes. Blending of polyether-esterurethanes with PLA caused ...

  12. Preparation and characterization of Polyhydroxyalkanoates (PHA) and Polylactide (PLA) blends

    OpenAIRE

    Gérard, Thibaut; Budtova, Tatiana

    2011-01-01

    International audience Polylactide (PLA) and poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) blends were prepared in different compositions by melt mixing. The miscibility of the two components was first characterized by differential scanning calorimetry (DSC) experiments, which showed the immiscibility of the components for all blend compositions. The morphology was studied using scanning electron microscope (SEM) and optical microscopy in reflection. Nodular and co-continuous morphologie...

  13. Photophysical studies of poly-isocyanopeptide based photovoltaic blends

    OpenAIRE

    Finlayson, C E; Whitney, A D

    2010-01-01

    Abstract We report a photophysical study of photovoltaic blends containing perylene-substituted polyisocyanide (pery-PIC) materials, using time-correlated single photon counting (TCSPC) and photo-induced absorption spectroscopy, and compare the key characteristics to analogous perylene-diimide (PDI) monomer blends with polythiophene- and polyfluorene-based conjugated polymers. Pery-PIC consists of semiconducting perylene units, which self-stack in a regular fashion around a rigid helical p...

  14. Study of the Blending Efficiency of Pitched Blade Impellers

    OpenAIRE

    I. Fořt; T. Jirout; Rieger, F.; Allner, R.; R. Sperling

    2001-01-01

    This paper presents an analysis of the blending efficiency of pitched blade impellers under a turbulent regime of flow of an agitated low viscous liquid. The conductivity method is used to determine of the blending (homogenization) time of miscible liquids in pilot plant mixing equipment with standard radial baffles. For the given homogeneity degree (98 %) a three-blade pitched blade impeller is tested with various off-bottom clearances, vessel/ impeller diameter ratios and various impeller p...

  15. Going Blended: New Challenges for Second Generation L2 Tutors

    OpenAIRE

    Nissen, Elke; Tea, Elena

    2012-01-01

    This study explores how second generation tutors within blended learning courses link the face-to-face and online course modalities - in their representations as well as through their pedagogical activities - and which aspects help them to feel involved in the course. The methodology used is a qualitative analysis of interviews with seven tutors of three different blended learning courses. The results show that most tutors indeed had difficulties gaining a deeper insight into the course desig...

  16. Enzymatic removal of cellulose from cotton/polyester fabric blends

    OpenAIRE

    Vasconcelos, Andreia; Paulo, Artur Cavaco

    2006-01-01

    The production of light-weight polyester fabrics from a polyester/cotton blended fabric, by means of the enzymatic removal of the cellulosic part of the material, was investigated. The removal of cotton from the blended fabric yielded more than 80% of insoluble microfibrillar material by the combined action of high beating effects and cellulase hydrolysis.Other major features of this enzymatic process for converting cotton fibers into microfibrillar material are bath ratio, enzyme dosage a...

  17. Influence of Coal Blending on Ash Fusibility in Reducing Atmosphere

    Directory of Open Access Journals (Sweden)

    Mingke Shen

    2015-05-01

    Full Text Available Coal blending is an effective way to organize and control coal ash fusibility to meet different requirements of Coal-fired power plants. This study investigates three different eutectic processes and explains the mechanism of how coal blending affects ash fusibility. The blended ashes were prepared by hand-mixing two raw coal ashes at five blending ratios, G:D = 10:90 (G10D90, G:D= 20:80 (G20D80, G:D = 30:70 (G30D70, G:D = 40:60 (G40D60, and G:D = 50:50 (G50D50. The samples were heated at 900 °C, 1000 °C, 1100 °C, 1200 °C, and 1300 °C in reducing atmosphere. XRD and SEM/EDX were used to identify mineral transformations and eutectic processes. The eutectic processes were finally simulated with FactSage. Results show that the fusion temperatures of the blended ashes initially decrease and then increase with the blending ratio, a trend that is typical of eutectic melting. Eutectic phenomena are observed in D100, G10D90, and G30D70 in different degrees, which do not appear in G100 and G50D50 for the lack of eutectic reactants. The main eutectic reactants are gehlenite, magnetite, merwinite, and diopside. The FactSage simulation results show that the content discrepancy of merwinite and diopside in the ashes causes the inconsistent eutectic temperatures and eutectic degrees, in turn decrease the fusion temperature of the blended ash and then increase them with the blending ratio.

  18. THE HANDBOOK OF BLENDED LEARNING:Global Perspectives, Local Designs

    OpenAIRE

    ATES, Reviewed By Alev

    2009-01-01

    THE HANDBOOK OF BLENDED LEARNING:Global Perspectives, Local Designs Curtis J. Bonk (ed.) and Charles R. Graham (ed.), Jay Cross (Foreword),Micheal G. Moore Foreword) ISBN: 978-0-7879-7758-0 Publisher: John Wiley & Sons, Inc. Pfeiffer Pages: 624 March 2006.Reviewed by Alev ATESPhD Student at Curriculum and Instruction,Lecturer at Computer Education and Instructional Technologies,Faculty of Education, Ege University, Izmir, TURKEYBlended learning or blended e-learning sounds like aconfusing ter...

  19. Physicochemical, microbiological and sensory evaluation of a bioactive food blend

    OpenAIRE

    Rosângela dos Santos Ferreira; Priscila Aiko Hiane; Rita de Cássia Avellaneda Guimarães; Maria Isabel Lima Ramos; Daniel Pecoraro Demarque; Júnia Elisa Carvalho de Meira

    2014-01-01

    The potential of functional foods to decrease the risks of chronic non-communicable diseases has motivated the development of products with beneficial effects on fat and carbohydrate metabolism. The present study aimed at analyzing the physicochemical, microbiological, and sensory properties of a bioactive food blend developed to help the nutritional therapy provided to hypolipidemic and hyperglycemic patients with HIV/AIDS treated with antiretroviral therapy. The food blend was evaluated for...

  20. Novel bio-based and biodegradable polymer blends

    Science.gov (United States)

    Yang, Shengzhe

    Most plastic materials, including high performance thermoplastics and thermosets are produced entirely from petroleum-based products. The volatility of the natural oil markets and the increasing cost of petroleum have led to a push to reduce the dependence on petroleum products. Together with an increase in environmental awareness, this has promoted the use of alternative, biorenewable, environmentally-friendly products, such as biomass. The growing interest in replacing petroleum-based products by inexpensive, renewable, natural materials is important for sustainable development into the future and will have a significant impact on the polymer industry and the environment. This thesis involved characterization and development of two series of novel bio-based polymer blends, namely polyhydroxyalkanoate (PHA)/polyamide (PA) and poly(lactic acid) (PLA)/soy protein. Blends with different concentrations and compatible microstructures were prepared using twin-screw extruder. For PHA/PA blends, the poor mechanical properties of PHA improved significantly with an excellent combination of strength, stiffness and toughness by adding PA. Furthermore, the effect of blending on the viscoelastic properties has been investigated using small-amplitude oscillatory shear flow experiments as a function of blend composition and angular frequency. The elastic shear modulus (G‧) and complex viscosity of the blends increased significantly with increasing the concentration of PHA. Blending PLA with soy protein aims at reducing production cost, as well as accelerating the biodegradation rate in soil medium. In this work, the mechanical, thermal and morphological properties of the blends were investigated using dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and tensile tests.

  1. Compatibility Studies on Elastomers and Polymers with Ethanol Blended Gasoline

    OpenAIRE

    J. S. Dhaliwal; M. S. Negi; G. S. Kapur; Kant, Shashi

    2014-01-01

    This paper reports the compatibility studies of 10% ethanol blended gasoline (E10) with four types of elastomer materials, namely, Neoprene rubber, Nitrile rubber, hydrogenated Nitrile butadiene rubber (HNBR), and Polyvinyl chloride/Nitrile butadiene rubber blend (PVC/NBR), and two types of plastic materials, namely, Nylon-66 and Polyoxymethylene (Delrin). These materials have applications in automotives as engine seals, gaskets, fuel system seals and hoses, and so forth. Two types of the eth...

  2. A Study on Students’ Views On Blended Learning Environment

    OpenAIRE

    Meryem YILMAZ SOYLU; AKKOYUNLU, BUKET

    2006-01-01

    In the 21st century, information and communication technologies (ICT) have developed rapidly and influenced most of the fields and education as well. Then, ICT have offered a favorable environment for the development and use of various methods and tools. With the developments in technology, blended learning has gained considerable popularity in recent years. Together with the developments it brought along the description of particular forms of teaching with technology. Blended learning is def...

  3. Biodegradable blends based on Polyhydroxybutyrate: structure and water diffusion

    OpenAIRE

    OLKHOV ANATOLIY ALEKSANDROVICH; MARKIN VALERIY SERGEEVICH; KOSENKO REGINA YUDELEVNA; GOLDSHTRAKH MARIANNA ALEKSANDROVNA; ZAIKOV GENNADIY EFREMOVICH; IORDANSKIY ALEKSEY LEONIDOVICH; PANKOVA YULIYA NIKOLAEVNA

    2015-01-01

    The present article focuses on the study of novel blends based on poly(3-hydroxybutyrate) (PHB) and polymers with different hydrophilicity (PELD, PA and PVA). Polymer blends were produced from five ratios of PHB/PELD in an effort to regulate the resistance to hydrolysis or (bio)degradation through the control of water permeability. The relation between the water transport and morphology (TEM data) shows the impact of polymer component ratio on the regulation of water flux in hydrophobic matri...

  4. Blends of Poly (lactic acid) with Thermoplastic Acetylated Starch

    Institute of Scientific and Technical Information of China (English)

    ZHANG Kun-yu; RAN Xiang-hai; ZHUANG Yu-gang; YAO Bin; DONG Li-song

    2009-01-01

    Blends of poly(lactic acid)(PLA) and thermoplastic acetylated starch(ATPS) were prepared by means of the melt mixing method. The results show that PLA and ATPS were partially miscible, which was confirmed with the measurement of T_g by dynamic mechanical analysis(DMA) and differrential scanning calorimetry(DSC). The mechanical and thermal properties of the blends were improved. With increasing the ATPS content, the elongation at break and impact strength were increased. The elongation at break increased from 5% of neat PLA to 25% of the blend PLA/ATPS40. It was found that the cold crystallization behavior of PLA changed evidently by addition of ATPS. The cold crystallization temperature(T_(cc)) of each of PLA/ATPS blends was found to shift to a lower temperature and the width of exothermic peak became narrow compared with that of neat PLA. The thermogravimetry analy-sis(TGA) results showed that the peak of derivative weight for ATPS moved to higher temperature with increasing PLA content in PLA/ATPS blends. It can be concluded that PLA could increase the thermal stability of ATPS. The rheological measurement reveals the melt elasticity and viscosity of the blends decreased with the increased concentration of ATPS, which was favorable to the processing properties of PLA.

  5. Curing characteristics of chlorosulphonated polyethylene and natural rubber blends

    Directory of Open Access Journals (Sweden)

    M. MARINOVIC-CINCOVIC

    2005-05-01

    Full Text Available The dependence of the Mooney scorch time and cure index on the blend ratio of chlorosulphonated polyethylene/natural rubber (CSM/SMR 20 CV and chlorosulphonated polyethylene/chlorinated natural rubber (CSM/Pergut S 40 blends were determined in the temperature range from 120 oC to 160 oC using a Monsanto Mooney viscometer. Semi-efficient vulcanization systems were used for the study. The morphology of the fracture surface of the crosslinked systems was determined by Scanning Electron Microscopy (SEM. The results showed that the scorch time decreased with increasing SMR 20 CV and Pergut S 40 contents. This observation is attributed to the increasing solubility of sulfur, as the content of SMR 20 CV and Pergut S 40 in the composition increased. For temperatures greater than 140 oC, the dependence of the scorch time on blend ratios diminishes, as enough thermal energy is available to overcome the activation energy of vulcanization. The differing curing characteristics of the two blends is explained by the compatibility factor of the respective blend. Morphological analysis of the blends shows a very satisfactory agreement.

  6. GAS PERMEATION OF SEGMENTED POLYURETHANES AND THEIR BLENDS WITH PVC

    Institute of Scientific and Technical Information of China (English)

    TIAN Minmin; ZHANG Xian; LIU Shangqi; XIAO Fengfei; HU Shiru; XU Mao

    1989-01-01

    Film specimens of four segmented polyurethanes with different soft segments, namely polycaprolactone,polytetramethylene adipate,polytetramethylene oxide and polypropylene oxide,and their blends with PVC of different compositions were obtained by solution cast. The permeability of these films to O2,N2 and H2 and their density were measured by using gas chromatography and technique of density gradient column. The polyether polyurethanes were found to have higher permeability than the polyester ones due to their low glass transition temperature and /6r the low density value.The blends of PVC and polyether polyurethanes, especially the PPO-based polyurethane, are incompatible, and their permeability coefficient-composition dependence has the typical S-shaped curves. PVC is well compatible with the soft segments in its blends with polyester polyurethanes. For these blends the composition dependence of permeability is characterized by a negative deviation from the semilogarithmic additivity rule,and it is possible to prepare blends having Tg 20 ℃ lower than that of PVC, but retaining its low permeability almost unchanged. results were discussed in according with the different approaches for the permeation behavior of compatible and incompatible blends.

  7. Preparation and emission characteristics of ethanol-diesel fuel blends

    Institute of Scientific and Technical Information of China (English)

    ZHANG Run-duo; HE Hong; SHI Xiao-yan; ZHANG Chang-bin; HE Bang-quan; WANG Jian-xin

    2004-01-01

    The preparation of ethanol-diesel fuel blends and their emission characteristics were investigated. Results showed the absolute ethanol can dissolve in diesel fuel at an arbitrary ratio and a small quantity of water(0.2%) addition can lead to the phase separation of blends. An organic additive was synthesized and it can develop the ability of resistance to water and maintain the stability of ethanol-diesel-trace amounts of water system. The emission characteristics of 10%, 20%, and 30% ethanol-diesel fuel blends, with or without additives, were compared with those of diesel fuel in a direct injection(DI) diesel engine. The experimental results indicated that the blend of ethanol with diesel fuel significantly reduced the concentrations of smoke, hydrocarbon(HC), and carbon monoxide(CO) in exhaust gas. Using 20% ethanol-diesel fuel blend with the additive of 2% of the total volume, the optimum mixing ratio was achieved, at which the bench diesel engine testing showed a significant decrease in exhaust gas. Bosch smoke number was reduced by 55%, HC emission by 70%, and CO emission by 45%, at 13 kW/1540 r/min. However, ethanol-diesel fuel blends produced a few ppm acetaldehydes and more ethanol in exhaust gas.

  8. Morphology and thermal behaviour of SAN/EPDM blends

    Directory of Open Access Journals (Sweden)

    2007-06-01

    Full Text Available Blends of styrene-acrylonitrile (SAN with ethylene-propylene-diene (EPDM with and without high impact polystyrene (HIPS as a compatibilizer were studied. One series of blends was prepared in composition 95/5, 90/10, 85/15, 80/20 and 60/40; and the second series of blends was prepared with addition of 5 wt % of HIPS. Their morphology and thermal behaviour were inspected by scanning electronic microscopy (SEM and dynamic mechanic analysis (DMA, respectively. Further on, blends were separated to their components by Soxlet extraction in selective solvent and characterized by Fourier Transform Infrared Spectroscopy (FTIR and gel permeation chromatography (GPC, respectively. The results of morphological observations revealed that the addition of a small percentage of compatibilizer decreases the domain size of the dispersed phase and the compatibility of the blends was enhanced. The shifts of values of glass temperatures (Tg in the examined blends also indicate that with addition of compatibilizer HIPS miscibility between SAN and EPDM is improved.

  9. MISCIBILITY, CRYSTALLIZATION AND MECHANICAL PROPERTIES OF PPC/PBS BLENDS

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this paper, melt blends of poly(propylene carbonate) (PPC) with poly(butylene succinate) (PBS) were characterized by dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), tensile testing, wide-angle X-ray diffraction (WAXD), polarized optical microscopy and thermogravimetric analysis (TGA). The results indicated that the glass transition temperature of PPC in the 90/10 PPC/PBS blend was decreased by about 11 K comparing with that of pure PPC. The presence of 10% PBS was partially miscible with PPC. The 90/10 PPC/PBS blend had better impact and tensile strength than those of the other PPC/PBS blends. The glass transition temperature of PPC in the 80/20, 70/30, and 60/40 PPC/PBS blends was improved by about 4.9 K, 4.2 K, and 13 K comparing with that of pure PPC, respectively; which indicated the immiscibility between PPC and PBS. The DSC results indicated that the crystallization of PBS became more difficult when the PPC content increased. The matrix of PPC hindered the crystallization process of PBS. While the content of PBS was above 20%, significant crystallization-induced phase separation was observed by polarized optical microscopy.It was found from the WAXD analysis that the crystal structure of PBS did not change, and the degree of crystallinity increased with increasing PBS content in the PPC/PBS blends.

  10. TIME-TEMPERATURE-MISCIBILITY AND MORPHOLOGY OF POLYOLEFIN BLENDS

    Institute of Scientific and Technical Information of China (English)

    Robert A.Shanks; Jun Li; Fei Chen; Gandara Amarasinghe

    2000-01-01

    Miscibility and crystallization have been studied for polypropylene-polyethylene and polyethylene-polyethylene blends. In the case of the polypropylene blends the composition of interest is 20% polypropylene. At this composition the polypropylene has been found to be soluble in linear low density polyethylene but insoluble in high, low and very low density polyethylenes. The miscibility has been concluded from the crystallization kinetics and polarised optical microscopy with a hot stage. Polyethylene-polyethylene blends have been formed from polymers with similar average branching content but where they have different melting temperatures. Important consequences are to introduce long branches into a polyethylene that only has short branches, and to modify the morphology of a polyethylenes so that haze, gloss and strain hardening are improved. Polyethylene blends must be developed after careful consideration of the branch content and distribution within each of the constituents. It is not sufficient to simply blend polyethylenes, with the desired range of properties, without regard to the miscibility of the blend composition.

  11. Morphological studies on block copolymer modified PA 6 blends

    Energy Technology Data Exchange (ETDEWEB)

    Poindl, M., E-mail: marcus.poindl@ikt.uni-stuttgart.de, E-mail: christian.bonten@ikt.uni-stuttgart.de; Bonten, C., E-mail: marcus.poindl@ikt.uni-stuttgart.de, E-mail: christian.bonten@ikt.uni-stuttgart.de [Institut für Kunststofftechnik, University of Stuttgart (Germany)

    2014-05-15

    Recent studies show that compounding polyamide 6 (PA 6) with a PA 6 polyether block copolymers made by reaction injection molding (RIM) or continuous anionic polymerization in a reactive extrusion process (REX) result in blends with high impact strength and high stiffness compared to conventional rubber blends. In this paper, different high impact PA 6 blends were prepared using a twin screw extruder. The different impact modifiers were an ethylene propylene copolymer, a PA PA 6 polyether block copolymer made by reaction injection molding and one made by reactive extrusion. To ensure good particle matrix bonding, the ethylene propylene copolymer was grafted with maleic anhydride (EPR-g-MA). Due to the molecular structure of the two block copolymers, a coupling agent was not necessary. The block copolymers are semi-crystalline and partially cross-linked in contrast to commonly used amorphous rubbers which are usually uncured. The combination of different analysis methods like atomic force microscopy (AFM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) gave a detailed view in the structure of the blends. Due to the partial cross-linking, the particles of the block copolymers in the blends are not spherical like the ones of ethylene propylene copolymer. The differences in molecular structure, miscibility and grafting of the impact modifiers result in different mechanical properties and different blend morphologies.

  12. Chemical and Enzymatic Hydrolysis of Polyurethane/Polylactide Blends

    Directory of Open Access Journals (Sweden)

    Joanna Brzeska

    2015-01-01

    Full Text Available Polyether-esterurethanes containing synthetic poly[(R,S-3-hydroxybutyrate] (R,S-PHB and polyoxytetramethylenediol in soft segments and polyesterurethanes with poly(ε-caprolactone and poly[(R,S-3-hydroxybutyrate] were blended with poly([D,L]-lactide (PLA. The products were tested in terms of their oil and water absorption. Oil sorption tests of polyether-esterurethane revealed their higher response in comparison to polyesterurethanes. Blending of polyether-esterurethanes with PLA caused the increase of oil sorption. The highest water sorption was observed for blends of polyether-esterurethane, obtained with 10% of R,S-PHB in soft segments. The samples mass of polyurethanes and their blends were almost not changed after incubation in phosphate buffer and trypsin and lipase solutions. Nevertheless the molecular weight of polymers was significantly reduced after degradation. It was especially visible in case of incubation of samples in phosphate buffer what suggested the chemical hydrolysis of polymer chains. The changes of surface of polyurethanes and their blends, after incubation in both enzymatic solutions, indicated on enzymatic degradation, which had been started despite the lack of mass lost. Polyurethanes and their blends, contained more R,S-PHB in soft segments, were degraded faster.

  13. Non-isothermal crystallization of PET/PLA blends

    International Nuclear Information System (INIS)

    Binary blends of poly(ethylene terephthalate) with poly(lactic acid), PET/PLA, were studied by differential scanning calorimetry and X-ray scattering. The PET/PLA blends, prepared by solution casting, were found to be miscible in the melt over the entire composition range. Both quenched amorphous and semicrystalline blends exhibit a single, composition dependent glass transition temperature. We report the non-isothermal crystallization of (a) PET, with and without the presence of PLA crystals and (b) PLA, with and without the presence of PET crystals. PET can crystallize in all blends, regardless of whether PLA is amorphous or crystalline, and degree of crystallinity of PET decreases as PLA content increases. In contrast, PLA crystallization is strongly affected by the mobility of the PET fraction. When PET is wholly amorphous, PLA can crystallize even in 70/30 blends, albeit weakly. But when PET is crystalline, PLA cannot crystallize when its own content drops below 0.90. These different behaviors may possibly be related to the tendency of each polymer to form constrained chains, i.e., to form the rigid amorphous fraction, or RAF. PET is capable of forming a large amount of RAF, whereas relatively smaller amount of RAF forms in PLA. Like the crystals, the rigid amorphous fraction of one polymer component may inhibit the growth of crystals of the other blend partner.

  14. A simple model to predict the biodiesel blend density as simultaneous function of blend percent and temperature.

    Science.gov (United States)

    Gaonkar, Narayan; Vaidya, R G

    2016-05-01

    A simple method to estimate the density of biodiesel blend as simultaneous function of temperature and volume percent of biodiesel is proposed. Employing the Kay's mixing rule, we developed a model and investigated theoretically the density of different vegetable oil biodiesel blends as a simultaneous function of temperature and volume percent of biodiesel. Key advantage of the proposed model is that it requires only a single set of density values of components of biodiesel blends at any two different temperatures. We notice that the density of blend linearly decreases with increase in temperature and increases with increase in volume percent of the biodiesel. The lower values of standard estimate of error (SEE = 0.0003-0.0022) and absolute average deviation (AAD = 0.03-0.15 %) obtained using the proposed model indicate the predictive capability. The predicted values found good agreement with the recent available experimental data. PMID:26050152

  15. On Crystallization in Polypropylene-Polyethylene Blends

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Blends of polypropylene(PP) and low-density polyethylene (LDPE) have beencrystallized to form open structures(“cluster spherulites”) where the droplets of the minorityPP are bridged by PP lamellae which have grown in the LDPE-rich matrix. These are studiedby permanganic etching followed by electron and optical microscopies. Two similar PP typesare compared, one synthesized with Ziegler-Natta catalyst and one with metallocenecatalyst. The metallocene-catalysed material crystallized much more slowly due to thepresence of regio defects in the chains, even though the overall concentration of tacticitydefects in the Ziegler-Natta material is much higher. A mechanism involving reversal ofhelical direction at the regio defect interfering with the regular chain packing in the crystal issuggested. Growth of “cluster spherulites” is faster in regions where low molecular weightmaterial is concentrated. It is slower where droplets are larger, and this is attributed tocompetition between PP lamellar growth in the matrix and diffusion of PP to alreadycrystallized droplets.

  16. De‐blending reverse‐time migration

    KAUST Repository

    Fei, Tong W.

    2010-10-17

    Reverse‐time migration (RTM), based on the full two‐way wave equation, has gained interest and become a popular imaging tool for complex structures in the last few years. The method is well‐known for its ability to better image the steeply dipping and overturned structures than the migration methods based on the one‐way wave equation extrapolation. However, the RTM image often contains low frequency and back‐scattering noise, and the imaging quality is sensitive to the migration velocity. In order to improve the RTM imaging quality and make the RTM image less sensitive to the velocity model, we developed an RTM de‐blending technique which separates upgoing and downgoing source and receiver wavefields, and then use them to construct final RTM images. Test results show that decomposed images obtained from only the downgoing source and receiver wavefields are less sensitive to velocity. It removes unwanted noise and migration artifacts from conventional RTM, and the imaging quality is greatly improved compared with a conventional RTM image.

  17. Polygonal Shape Blending with Topological Evolutions

    Institute of Scientific and Technical Information of China (English)

    Li-Gang Liu; Bo Zhang; Bai-Ning Guo; Heung-Yeung Shum

    2005-01-01

    This paper presents a new general approach to blend 2D shapes with different topologies. All possible topolog ical evolutions are classified into three types by attaching three different topological cells. This formalism is resulted from Morse theory on the behavior of the 3D surface around a non-degenerate critical point. Also we incorporate degenerate topological evolutions into our framework which produce more attractive morphing effects. The user controls the morph by specifying the types of topological evolutions as well as the feature correspondences between the source and target shapes.Some techniques are also provided to control the vertex path during the morphing process. The amount of user input required to produce a morph is directly proportional to the amount of control the user wishes to impose on the process.The user may allow the system to automatically generate the morph as well. Our approaches are totally geometric based and are easy and fast enough in fully interactive time. Many experimental results show the applicability and flexibility of our approaches.

  18. Thermal Stabilization FY 1999 blend plan

    International Nuclear Information System (INIS)

    This Blend Plan documents the alternate feed material items for the thermal stabilization process that will be used in place of the metal items that were originally planned to be processed. Problems with resolution of the safety basis for the metal items resulted in the decision to run material that already had an established safety basis. Various in process and scrap recovery items stored in gloveboxes, plutonium oxide and plutonium oxide mixed with uranium oxide stored in 2736-Z vaults will be processed through the stabilization furnaces until the safety basis for the metal items has been resolved. The purpose of thermal stabilization is to heat the material to 1000 degrees Celsius to drive off all volatile materials and leave the plutonium and/or uranium as oxides. The stabilized material will be sampled to determine the Loss On Ignition (LOI). The stabilized material must meet LOI of less than 0.5% to be acceptable for storage under DOE-STD-3013-94 specifications. Out of specification material will be recycled through the furnaces until the LOI limits are met

  19. Recombinant protein blends: silk beyond natural design.

    Science.gov (United States)

    Dinjaski, Nina; Kaplan, David L

    2016-06-01

    Recombinant DNA technology and new material concepts are shaping future directions in biomaterial science for the design and production of the next-generation biomaterial platforms. Aside from conventionally used synthetic polymers, numerous natural biopolymers (e.g., silk, elastin, collagen, gelatin, alginate, cellulose, keratin, chitin, polyhydroxyalkanoates) have been investigated for properties and manipulation via bioengineering. Genetic engineering provides a path to increase structural and functional complexity of these biopolymers, and thereby expand the catalog of available biomaterials beyond that which exists in nature. In addition, the integration of experimental approaches with computational modeling to analyze sequence-structure-function relationships is starting to have an impact in the field by establishing predictive frameworks for determining material properties. Herein, we review advances in recombinant DNA-mediated protein production and functionalization approaches, with a focus on hybrids or combinations of proteins; recombinant protein blends or 'recombinamers'. We highlight the potential biomedical applications of fibrous protein recombinamers, such as Silk-Elastin Like Polypeptides (SELPs) and Silk-Bacterial Collagens (SBCs). We also discuss the possibility for the rationale design of fibrous proteins to build smart, stimuli-responsive biomaterials for diverse applications. We underline current limitations with production systems for these proteins and discuss the main trends in systems/synthetic biology that may improve recombinant fibrous protein design and production. PMID:26686863

  20. Refining and blending of aviation turbine fuels.

    Science.gov (United States)

    White, R D

    1999-02-01

    Aviation turbine fuels (jet fuels) are similar to other petroleum products that have a boiling range of approximately 300F to 550F. Kerosene and No.1 grades of fuel oil, diesel fuel, and gas turbine oil share many similar physical and chemical properties with jet fuel. The similarity among these products should allow toxicology data on one material to be extrapolated to the others. Refineries in the USA manufacture jet fuel to meet industry standard specifications. Civilian aircraft primarily use Jet A or Jet A-1 fuel as defined by ASTM D 1655. Military aircraft use JP-5 or JP-8 fuel as defined by MIL-T-5624R or MIL-T-83133D respectively. The freezing point and flash point are the principle differences between the finished fuels. Common refinery processes that produce jet fuel include distillation, caustic treatment, hydrotreating, and hydrocracking. Each of these refining processes may be the final step to produce jet fuel. Sometimes blending of two or more of these refinery process streams are needed to produce jet fuel that meets the desired specifications. Chemical additives allowed for use in jet fuel are also defined in the product specifications. In many cases, the customer rather than the refinery will put additives into the fuel to meet their specific storage or flight condition requirements. PMID:10189575

  1. On unfamiliar Italian lexical blends from names and nouns

    Directory of Open Access Journals (Sweden)

    Silvia Cacchiani

    2011-05-01

    Full Text Available Italian has recently witnessed a steady increase in the use of unfamiliar lexical blends from names and nouns. While they serve an identificatory and descriptive function (in the sense of Anderson 2007, blends are created in extragrammatical morphology with careful attention to the semantic concepts encoded by the individual SWs, understanding blends from names and nouns depends on the decoder's direct or surrogate experience of the related reference. Significantly, blends are coined out of the need to be relevant (Sperber/Wilson 1990 and show various degrees of morphotactic and morphosemantic transparency (Thornton 1986; Dressler 1987, 1999, which makes them memorable (Lehrer 2003. In this paper we therefore address blends from names and nouns within the framework of the Naturalness Theory (Thornton 1986; Dressler et al. 1987; Dressler 1999. As will be seen, although blends are not created in rule-based grammars, some overall preferences and regularities can be observed for more core items (cf. Bat-El/Cohen, in press, within the framework of Optimality Theory under the principle of saliency (Dressler 1987. Focusing on their morphosyntactic transparency, we provide a typology of Italian unfamiliar blends from names and nouns functioning as naming units in order to delimit the category and reassess current typologies. While we allow for a continuum of morphotactic transparency within the prototypical category of extragrammatcial subtractive word-formations, we slightly adapt Ronneberger-Sibold (2006 and suggest we distinguish between blends on the one hand and the neighbouring category of clipped compounds on the other. Moving on to morphosemantic transparency and conceptual motivation, we use concepts from Cognitive Grammar, Cognitive Metaphor Theory and theories of Conceptual Blending (cf. Lakoff/Johnson 1980; Langacker 1987; Ruiz de Mendoza 1998, 2000; Kemmer 2003 to provide some preliminary remarks on specific subtypes, and blends from

  2. Microstructured Polymer Blend Surfaces Produced by Spraying Functional Copolymers and Their Blends

    Directory of Open Access Journals (Sweden)

    Nelson Vargas-Alfredo

    2016-05-01

    Full Text Available We described the fabrication of functional and microstructured surfaces from polymer blends by spray deposition. This simple technique offers the possibility to simultaneously finely tune the microstructure as well as the surface chemical composition. Whereas at lower polymer concentration, randomly distributed surface micropatterns were observed, an increase of the concentration leads to significant changes on these structures. On the one hand, using pure homopolystyrene fiber-like structures were observed when the polymer concentration exceeded 30 mg/mL. Interestingly, the incorporation of 2,3,4,5,6-pentafluorostyrene changed the morphology, and, instead of fibers, micrometer size particles were identified at the surface. These fluorinated microparticles provide superhydrophobic properties leading to surfaces with contact angles above 165°. Equally, in addition to the microstructures provided by the spray deposition, the use of thermoresponsive polymers to fabricate interfaces with responsive properties is also described. Contact angle measurements revealed variations on the surface wettability upon heating when blends of polystyrene and polystyrene-b-poly(dimethylaminoethyl methacrylate are employed. Finally, the use of spraying techniques to fabricate gradient surfaces is proposed. Maintaining a constant orientation, the surface topography and thus the contact angle varies gradually from the center to the edge of the film depending on the spray angle.

  3. Preparation of Biodegradable Silk Fibroin/Alginate Blend Films for Controlled Release of Antimicrobial Drugs

    Directory of Open Access Journals (Sweden)

    Yaowalak Srisuwan

    2013-01-01

    Full Text Available Silk fibroin (SF/alginate blend films have been prepared for controlled release of tetracycline hydrochloride, an antimicrobial model drug. The blend films were analysed by Fourier transform infrared (FTIR spectroscopy, scanning electron microscopy (SEM, and UV-vis spectroscopy. The functional groups of the SF/alginate blends were monitored from their FTIR spectra. The homogeneity of the blend films was observed from SEM images. The dissolution and film transparency of the blend films depended on the SF/alginate blend ratio. The in vitro drug release profile of the blend films was determined by plotting the cumulative drug release versus time. It was found that the drug release significantly decreased as the SF/alginate blend ratio increased. The results demonstrated that the SF/alginate blend films should be a useful controlled-release delivery system for water-soluble drugs.

  4. Blending Of Radioactive Salt Solutions In Million Gallon Tanks

    Energy Technology Data Exchange (ETDEWEB)

    Leishear, Robert A.; Lee, Si Y.; Fowley, Mark D.; Poirier, Michael R.

    2012-12-10

    Research was completed at Savannah River National Laboratory (SRNL) to investigate processes related to the blending of radioactive, liquid waste, salt solutions in 4920 cubic meter, 25.9 meter diameter storage tanks. One process was the blending of large salt solution batches (up to 1135 ? 3028 cubic meters), using submerged centrifugal pumps. A second process was the disturbance of a settled layer of solids, or sludge, on the tank bottom. And a third investigated process was the settling rate of sludge solids if suspended into slurries by the blending pump. To investigate these processes, experiments, CFD models (computational fluid dynamics), and theory were applied. Experiments were performed using simulated, non-radioactive, salt solutions referred to as supernates, and a layer of settled solids referred to as sludge. Blending experiments were performed in a 2.44 meter diameter pilot scale tank, and flow rate measurements and settling tests were performed at both pilot scale and full scale. A summary of the research is presented here to demonstrate the adage that, ?One good experiment fixes a lot of good theory?. Experimental testing was required to benchmark CFD models, or the models would have been incorrectly used. In fact, CFD safety factors were established by this research to predict full-scale blending performance. CFD models were used to determine pump design requirements, predict blending times, and cut costs several million dollars by reducing the number of required blending pumps. This research contributed to DOE missions to permanently close the remaining 47 of 51 SRS waste storage tanks.

  5. Properties and durability of metakaolin blended cements

    Directory of Open Access Journals (Sweden)

    Ezzat, El-Sayed

    2010-09-01

    Full Text Available This paper evaluates the optimal calcination temperature and replacement ratio to ensure high metakaolin (MK pozzolanicity in blended cement. The MK used was prepared by firing two types of local at temperatures ranging from 700 to 850 ºC. Dry blends of ordinary Portland cement (OPC and varying proportions of MK were mixed with the amount of water required to ensure optimal consistency of the resulting pastes. The specimens were cured at 100% RH for 24 h and then immersed in water for 3, 7, 28, 90 or 180 days. At each test time, the degree of hydration and compressive strength of the hardened cement pastes were measured The findings showed that the most suitable calcination temperature to obtain metakaolin is 700 ºC, while the optimal replacement ratio ranges from 25 to 30%. DTA was used to determine the phases comprising the hydration products forming at the ages studied. Pure OPC and OPC-MK specimens were immersed in 3% NaCl and 5% MgSO4 solutions for 30, 90 and 180 days to measure their durability. The OPC-MK pastes immersed in the 3% NaCl solution were observed to be highly resistant to chloride attack.

    El presente trabajo evalúa el comportamiento puzolánico de metacaolín (MK, producto de la calcinación a distintas temperaturas de dos tipos de caolín local de composiciones químicas diferentes, al incorporarse al cemento en diferentes proporciones. Se preparó un cemento adicionado mediante la mezcla en seco de cemento Portland ordinario (OPC y metacaolín (MK, a los que se añadió la cantidad óptima de agua para obtener una pasta de la consistencia deseada. Las probetas se curaron a una HR del 100% durante 24 horas, sumergiéndose posteriormente en agua durante 3, 7, 28, 90 o 180 días. A cada tiempo de ensayo se controló el grado de hidratación de las pastas endurecidas y se comprobó la resistencia a la compresión de las probetas cúbicas a las edades de curado establecidas. Los resultados obtenidos indican que la

  6. Glass powder blended cement hydration modelling

    Science.gov (United States)

    Saeed, Huda

    The use of waste materials in construction is among the most attractive options to consume these materials without affecting the environment. Glass is among these types of potential waste materials. In this research, waste glass in powder form, i.e. glass powder (GP) is examined for potential use in enhancing the characteristics of concrete on the basis that it is a pozzolanic material. The experimental and the theoretical components of the work are carried out primarily to prove that glass powder belongs to the "family" of the pozzolanic materials. The chemical and physical properties of the hydrated activated glass powder and the hydrated glass powder cement on the microstructure level have been studied experimentally and theoretically. The work presented in this thesis consists of two main phases. The first phase contains experimental investigations of the reaction of glass powder with calcium hydroxide (CH) and water. In addition, it includes experiments that are aimed at determining the consumption of water and CH with time. The reactivity, degree of hydration, and nature of the pore solution of the glass powder-blended cement pastes and the effect of adding different ratios of glass powder on cement hydration is also investigated. The experiments proved that glass powder has a pozzolanic effect on cement hydration; hence it enhances the chemical and physical properties of cement paste. Based on the experimental test results, it is recommended to use a glass powder-to-cement ratio (GP/C) of 10% as an optimum ratio to achieve the best hydration and best properties of the paste. Two different chemical formulas for the produced GP C-S-H gel due to the pure GP and GP-CH pozzolanic reaction hydration are proposed. For the pure GP hydration, the produced GP C-S-H gel has a calcium-to-silica ratio (C/S) of 0.164, water-to-silica ratio (H/S) of 1.3 and sodium/silica ratio (N/S) of 0.18. However, for the GP-CH hydration, the produced GP C-S-H gel has a C/S ratio of 1

  7. Low-Temperature Miscibility of Ethanol-Gasoline-Water Blends in Flex Fuel Applications

    DEFF Research Database (Denmark)

    Johansen, T.; Schramm, Jesper

    2009-01-01

    The miscibility of blends of gasoline and hydrous ethanol was investigated experimentally at - 25 degrees C and - 2 degrees C. Furthermore, the maximum water content was found for ethanol in flex fuel blends. The results strongly indicate that blends containing ethanol with a water content above...... that of the ethanol/water azeotrope (4.4% water by mass) can be used as Flex Fuel blends together with gasoline at ambient temperatures of 25 degrees C and 2 degrees C, without phase separation occurring. Additionally, it was shown that the ethanol purity requirement of ethanol-rich flex fuel blends...... falls with increasing ethanol content in the gasoline-rich flex fuel blend....

  8. Morphology and properties of PBT/SEBS and PBT/SEBS-G-MAH blends

    Science.gov (United States)

    Lu, Xiang; Qu, Jinping

    2016-03-01

    A series of poly (butylene terephthlate) (PBT)/ styrene-ethylene/butylene-styrene (SEBS) and PBT/ (styrene-ethylene/butylene-styrene)-G-(Maleic anhydride) (SEBS-G-MAH) blends were prepared by melt blending method. And the morphology, mechanical properties were studied to identify the effect of SEBS or SEBS-G-MAH weight fraction on the properties of blends. SEM show that the minor phase was hardly distinguishable in the blend of PBT/SEBS-G-MAH as the result of the improvement in dispersibility, compared with PBT/SEBS blends. These results lead to the different mechanical properties between PBT/SEBS and PBT/SEBS-G-MAH blends.

  9. Effect of irradiation on the prevulcanized latex/low nitrosamines latex blends

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, Pairu; Zin, Wan Manshol Wan [Malaysian Nuclear Agency, 43000 kajang, Selangor (Malaysia); Daik, Rusli [Faculty of Science and Technology, Universiti Kebangsaan Malaysia,43600 bangi, Selangor (Malaysia)

    2015-09-25

    Radiation Prevulcanized Natural Rubber Latex (RVNRL) was blended with Low Nitrosamines Latex (LNL) at different composition ratio. Methyl Metachrylate (MMA) was added for grafting onto the blended latex. Blended latex was subjected to gamma irradiation at various doses up to 8kGy. The mechanical properties and FTIR analysis were investigated as a function of the blended composition and irradiation dose. It was found that blending at specific ratio and gamma irradiation at specific dose led to significant improvement on the properties of the latex. The optimum mechanical properties was attained at a total blending ratio of 70% RVNRL and 30% of LNL.

  10. Irradiation crosslinking of poly(vinylchloride)/ epoxidized natural rubber blend

    International Nuclear Information System (INIS)

    Irradiation crosslinking of 50/50 poly(vinyl chloride)/ epoxidized natural rubber (PVC/ ENR) was studied with particular attention to blending parameters, addition of a crosslinking agent (TMPTA) and addition of an antioxidant (Irganox 1010). The 50/ 50 PVC/ ENR blend was prepared with a Brabender Plasticoder. The blend was irradiated by using a 3 MeV electron beam accelerator with doses ranging from 0-200 kGy. Changes in tensile properties, hardness, gel fraction, dynamic mechanical and morphological properties of the blends with irradiation doses were investigated. Evidences from DMA, FTIR, Foz Model, Charlesby-Pineer equation and crosslink density results were also employed to characterize the occurrence of irradiation-induced crosslinking. The possible mechanism of crosslinking induced by the irradiation between PVC and ENR was also proposed. It was observed that the mixing parameters such as temperature and time studied in this work are important in enhancement of irradiation induced crosslinking in PVC/ ENR blend. Results revealed that a readily compatible blend prepared at 150 degree Celsius, 50 rpm and 10 minutes of minimum mixing time enjoy maximum benefit from irradiation. However, irradiation was found to impart compatibility to the partially compatible PVC/ ENR blends prepared at 140 degree Celsius, 50 rpm and 10 minutes due to the irradiation-induced crosslinking. Electron beam initiated crosslinking of PVC/ ENR, containing trimethylolpropane triacrylate (TMPTA), has been carried out over a range of irradiation doses (20-200 kGy) and concentrations of TMPTA (1 to 5 phr). Blends containing 3-4 phr TMPTA were found to achieve optimum crosslinking, which in effect causes a maximum in tensile strength at 70 kGy. It was evident from FTIR spectra that the irradiation-induced reaction in PVC/ ENR blend involves the ring opening of the epoxy group to form ether bonds. Upon irradiation, the fractured surface topography changes from ductile to brittle as results

  11. Characterization of particle size distribution from diesel engines fueled with palm-biodiesel blends and paraffinic fuel blends

    Science.gov (United States)

    Lin, Yuan-Chung; Lee, Chia-Fon; Fang, Tiegang

    Biodiesels are promoted as alternative fuels and their applications in diesel engines have been investigated by many researchers. However, the particle size distribution emitted from heavy-duty diesel engines fueled with palm-biodiesel blended with premium diesel fuel and paraffinic fuel blended with palm-biodiesel has seldom been addressed. Thus, five test fuels were used in this work to study the particle size distribution: D100 (premium diesel fuel), B100 (100% palm-biodiesel), B20 (20 vol% palm-biodiesel+80 vol% D100), BP9505 (95 vol% paraffinic fuel+5 vol% palm-biodiesel) and BP8020 (80 vol% paraffinic fuel+20 vol% palm-biodiesel). A Micro-Orifice Uniform Deposit Impactor (MOUDI) equipped with aluminum filters was used to collect size-resolved samples. Experimental results indicated that palm-biodiesel blends and paraffinic fuel blends could improve combustion efficiency in diesel engines, but pure palm-biodiesel could cause incomplete combustion. Adding palm-biodiesel to diesel fuel would slightly increase particles with diameter fuel blends could decrease particles with diameter fuels. On the other hand, a greater fraction of particulate matter of BP9505 and BP8020 existed in coarse particles (diameter: 2.5-10 μm). Energy efficiency also increases significantly by 12.3-15.1% with the introduction of paraffinic fuel blends into the engine. Nevertheless, paraffinic fuel blends also reduce the emission of particulate matters by 36.0-38.4%. Carbon monoxide was decreased by 36.8-48.5%. Total hydrocarbon is 39.6-41.7% less than diesel fuel combustion. Nitrogen oxides emission is about 5% lower for paraffinic fuel. These results show that paraffinic fuel can be very competitive and replaced diesel fuels in the future.

  12. Influence of biodiesel blending on physicochemical properties and importance of mathematical model for predicting the properties of biodiesel blend

    International Nuclear Information System (INIS)

    Highlights: • Short identification of selected biodiesel feedstock. • Review of physicochemical properties for blended biodiesel. • Mathematical model for predicting properties of various biodiesel blends. - Abstract: The growing demand for green world serves as one of the most significant challenges of modernization. Requirements like largest usage of energy for modern society as well as demand for friendly milieu create a deep concern in field of research. Biofuels are placed at the peak of the research arena for their underlying benefits as mentioned by multiple researches. Out of a number of vegetable oils, only a few are used commercially for biodiesel production. Due to various limitations of edible oil, non-edible oils are becoming a profitable choice. Till today, very little percentage of biodiesel is used successfully in engine. The research is still continuing for improving the biodiesel usage level. Recently, it is found that the blended biodiesel from more than one feedstock provides better performance in engine. This paper reviews the physicochemical properties of different biodiesel blends obtained from various feedstocks with a view to properly understand the fuel quality. Moreover, a short description of each feedstock is given along with graphical presentation of important properties for various blend percentages from B0 to B100. Finally, mathematical model is formed for predicting various properties of biodiesel blend with the help of different research data by using polynomial curve fitting method. The results obtained from a number of literature based on this work shows that the heating value of biodiesel is about 11% lower than diesel except coconut (14.5% lower) whereas kinematic viscosity is in the range of 4–5.4 mm2/s. Flash point of all biodiesels are more than 150 °C, except neem and coconut. Cold flow properties of calophyllum, palm, jatropha, moringa are inferior to others. This would help to determine important properties of

  13. Dispersion of organophilic Ag nanoparticles in PS-PMMA blends

    International Nuclear Information System (INIS)

    The preparation of stable composites with well-controlled particle location is one of the challenges in formulating new polymer/nanoparticle mixtures. In this study, cetyltriammonium bromide (CTAB)-capped monodisperse Ag nanoparticles were prepared and mixed with an equimass blend of polystyrene (PS) and poly(methyl methacrylate) (PMMA) in solution. The surface of the blend film without nanoparticles showed spherical pits with a size of 4.5 μm in diameter. The integration of CTAB-capped nanoparticles into the blend film developed surface bumps with a size of 0.4 μm in diameter. The organophilic Ag nanoparticles were distributed heterogeneously in the immiscible PS-PMMA blend. When the diameter of particle domains reached approximately 20 nm, particles were preferentially located at the interface of the PS and PMMA domains. Larger particle domains with a diameter of 90 nm were found to be in the PMMA-rich phase. Isothermal post-treatment of the PS-PMMA/Ag composite films directs the particle domains into PS domains. Thermodynamic factors that contribute to the observed morphologies are discussed. - Graphical abstract: Display Omitted - Highlights: • Ag nanoparticles were obtained throughout a redox reaction. • Electrostatically stabilized particles were capped by CTAB. • The organophilic particles were added into PS and PMMA blend system. • The placement of the Ag particle domains was readily controlled. • The amount of CTAB and post treatment of the composites were system parameters

  14. The Viscoelastic Behavior of Polymer/Oligomer Blends

    Science.gov (United States)

    Zheng, Wei; McKenna, Gregory; Simon, Sindee

    2009-03-01

    The dynamics in athermal blends of poly(α-methyl styrene) (PaMS) and its short chain oligomer are investigated using rheometry and differential scanning calorimetry (DSC). Master curves for the dynamic shear responses, G' and G", are successfully constructed for both the pure materials and the blends, indicating the validity of the time-temperature superposition principle. The temperature dependence of the shift factor follows the WLF (Williams-Landel-Ferry) behavior over the temperature range studied, and for the blends, the dependence is dominated by the high mobility oligomer. The discrete relaxation spectra of the materials are calculated and are found to be broader for the blends than for the pure materials. A similar domination of the dynamics by the oligomer is observed in DSC enthalpy recovery studies and in the broadened glass transition from DSC. The ability to predict the dynamic responses of the blends from the responses of the neat materials is examined, and whether this prediction needs to incorporate the self-concentration idea as described in Colmenero's model will be discussed.

  15. Pedagogical and Design Aspects of a Blended Learning Course

    Directory of Open Access Journals (Sweden)

    Karen Precel, Yoram Eshet-Alkalai, Yael Alberton

    2009-04-01

    Full Text Available Based on recent research reports, the blended learning model, which combines face-to-face and online learning, is now the preferred model for online course design. Its superiority over online learning, which lacks face-to-face interaction, is evident from studies that examined both student achievement and satisfaction. Nevertheless, there is ambiguity in the literature and in the field regarding the proper implementation of blended learning and the optimal proportions between online and F2F components in various learning scenarios. The range of contradictory reports in recent literature on the potential of different blended learning models shows the need for more research on specific blended learning courses in order to establish proper standards for effective course design and implementation. The present evaluation study focuses on students’ perceptions of pedagogical and design issues related to a new model for blended learning used in a graduate-level course at the Open University of Israel. Fifty-eight of the course’s 91 students participated in the study and completed a questionnaire regarding three major aspects of the course design: (1 pedagogy, (2 textbook format (print vs. digital, and (3 learning environment usability. The results illustrate the importance of completing the pedagogical and visual design of online learning in advance. Also, the course model suggests ways to bridge the gaps between students and instructors and students and their peers, which are typical of online learning in general and of open universities in particular.

  16. Blended implicit methods for the numerical solution of DAE problems

    Science.gov (United States)

    Brugnano, Luigi; Magherini, Cecilia; Mugnai, Filippo

    2006-05-01

    Recently, a new approach for solving the discrete problems, generated by the application of block implicit methods for the numerical solution of initial value problems for ODEs, has been devised [L. Brugnano, Blended block BVMs (B3VMs): a family of economical implicit methods for ODEs, J. Comput. Appl. Math. 116 (2000) 41-62; L. Brugnano, C. Magherini, Blended implementation of block implicit methods for ODEs, Appl. Numer. Math. 42 (2002) 29-45; L. Brugnano, D. Trigiante, Block implicit methods for ODEs, in: D. Trigiante (Ed.), Recent Trends in Numerical Analysis, Nova Science Publishers, New York, 2001, pp. 81-105]. This approach is based on the so-called blended implementation of the methods, giving corresponding blended implicit methods. The latter have been implemented in the computational code BiM [L. Brugnano, C. Magherini, The BiM code for the numerical solution of ODEs, J. Comput. Appl. Math. 164-165 (2004) 145-158]. Blended implicit methods are here extended to handle the numerical solution of DAE problems, resulting in a straightforward generalization of the basic approach.

  17. Electrospun gelatin/polyurethane blended nanofibers for wound healing

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Eun; Heo, Dong Nyoung; Lee, Jung Bok; Kwon, Il Keun [Department of Oral Biology, School of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Kim, Jong Ryul; Park, Sang Hyuk [Conservative Dentistry and Institute of Oral Biology, School of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Jeon, Seong Ho, E-mail: kwoni@khu.ac.k [College of Pharmacy, Kangwon National University, Chuncheon 200-701 (Korea, Republic of)

    2009-08-15

    In this study, we prepared a blended nanofiber scaffold using synthetic and natural polymers, polyurethane (PU) and gelatin respectively, using the electrospinning method to prepare a material for wound dressing. In order to confirm the properties of this gelatin/PU blended nanofiber scaffold, we performed scanning electron microscopy, atomic force microscopy, attenuated total reflectance Fourier-transform infrared spectroscopy, thermal gravimetric analysis, contact angle, water uptake, mechanical property, recovery, and degradation tests, and cellular response. The results obtained indicate that the mean diameter of these nanofibers was uniformly electrospun and ranged from 0.4 to 2.1{mu}m. According to the results, when the amount of gelatin in the blended solution decreased, the contact angle increased and water uptake of the scaffold decreased concurrently. In the mechanical tests, the blended nanofibrous scaffolds were elastic, and elasticity increased as the total amount of PU increased. Moreover, as the total amount of gelatin increased, the cell proliferation increased with the same amount of culture time. Therefore, this gelatin/PU blended nanofiber scaffold has potential application for use as a wound dressing.

  18. How to Mix the Ingredients for a Blended Course Recipe

    Directory of Open Access Journals (Sweden)

    Antoanela Naaji

    2015-12-01

    Full Text Available Over the last years, the growing ubiquity of Social Media, the emerging mobile technologies and the augmented reality become more deeply integrated into the teaching-learning process and also create new opportunities for reinventing the way in which educational actors both perceive and access learning. The major challenges in education that involve tremendous development and innovation are blended courses/ flipped classrooms integrating Social Media (SM, Open Educational Resources (OER and Massive Open Online Courses (MOOC (Johnson et al., 2014. This paper focuses on evaluating the e-learning experiences of various actors in the Romanian educational system. There is a tendency to use virtual learning environments with increasing frequency in higher education, many participants experiencing both online and blended courses. Another issue approached in this paper concerns the relevance of the components of online/ blended courses. In this context, the paper analyzes the importance of these elements with respect to various fields, such as: exact sciences, social sciences, humanistic studies, medical sciences, etc. In conclusion, we identify the most relevant elements in the development of online/ blended courses for various domains. The results will emphasize the standards required for evaluating the quality of online and blended courses.

  19. Electrospun gelatin/polyurethane blended nanofibers for wound healing.

    Science.gov (United States)

    Kim, Sung Eun; Heo, Dong Nyoung; Lee, Jung Bok; Kim, Jong Ryul; Park, Sang Hyuk; Jeon, Seong Ho; Kwon, Il Keun

    2009-08-01

    In this study, we prepared a blended nanofiber scaffold using synthetic and natural polymers, polyurethane (PU) and gelatin respectively, using the electrospinning method to prepare a material for wound dressing. In order to confirm the properties of this gelatin/PU blended nanofiber scaffold, we performed scanning electron microscopy, atomic force microscopy, attenuated total reflectance Fourier-transform infrared spectroscopy, thermal gravimetric analysis, contact angle, water uptake, mechanical property, recovery, and degradation tests, and cellular response. The results obtained indicate that the mean diameter of these nanofibers was uniformly electrospun and ranged from 0.4 to 2.1 microm. According to the results, when the amount of gelatin in the blended solution decreased, the contact angle increased and water uptake of the scaffold decreased concurrently. In the mechanical tests, the blended nanofibrous scaffolds were elastic, and elasticity increased as the total amount of PU increased. Moreover, as the total amount of gelatin increased, the cell proliferation increased with the same amount of culture time. Therefore, this gelatin/PU blended nanofiber scaffold has potential application for use as a wound dressing. PMID:19671952

  20. Electrospun gelatin/polyurethane blended nanofibers for wound healing

    International Nuclear Information System (INIS)

    In this study, we prepared a blended nanofiber scaffold using synthetic and natural polymers, polyurethane (PU) and gelatin respectively, using the electrospinning method to prepare a material for wound dressing. In order to confirm the properties of this gelatin/PU blended nanofiber scaffold, we performed scanning electron microscopy, atomic force microscopy, attenuated total reflectance Fourier-transform infrared spectroscopy, thermal gravimetric analysis, contact angle, water uptake, mechanical property, recovery, and degradation tests, and cellular response. The results obtained indicate that the mean diameter of these nanofibers was uniformly electrospun and ranged from 0.4 to 2.1 μm. According to the results, when the amount of gelatin in the blended solution decreased, the contact angle increased and water uptake of the scaffold decreased concurrently. In the mechanical tests, the blended nanofibrous scaffolds were elastic, and elasticity increased as the total amount of PU increased. Moreover, as the total amount of gelatin increased, the cell proliferation increased with the same amount of culture time. Therefore, this gelatin/PU blended nanofiber scaffold has potential application for use as a wound dressing.

  1. Practical use of mathematical methods of optimizing coal blends

    Energy Technology Data Exchange (ETDEWEB)

    Kaziszyn, I.; Lojek, M.; Postrzednik, S.

    1977-12-01

    Using the method of planned experiment, the interdependence of coke quality and composition of coal blend charged in the coke ovens has been investigated. In the mathematical equations the following factors defining mechanical strength of coke were used: M10, M20, M40, percentage of coke with grain size over 60mm and IRSID factor (for coke with size over 60mm and with size from 20 to 60mm). Four types of coal were used to prepare the coal blends. Usefulness of the method of planned experiment has been tested in the laboratory and in industrial plants. This method can be successfully used in the calculation of quality factors of coke and in optimizing these factors by changing the composition of the coal blend. The model of the coal blend composition in the form of diagrams or tables is not complicated to use but it is correct only when it is applied to the types of coal and conditions of coking taken into account when the model was constructed. An individual model should therefore be worked out for each carbonization plant and for each coal blend.

  2. Techno- teaching convergence of blended learning: transitions and prospects

    Directory of Open Access Journals (Sweden)

    Osbaldo Turpo Gebera

    2013-12-01

    Full Text Available Since its emergence in the educational context, the Blended Learning emerges as a modality with its own identity. According to its evolution, runs through presentiality configured contexts and virtuality. In a first stage, stood as a mixed or combined mode, then advanced to integration, which resulted in the dilution of its components. The progressive social changes, technological and cultural towards convergence, today brings a new north-mode, given the confluence of pedagogical and technological mediations in the training process. This position places him in a new trend that more than a possibility, actually represents a more explicable on the future of Blended Learning. The pedagogical and technological convergence of media and resources is a more consistent way to understand the mode, while providing a framework for interpreting the transition and development prospects of the Blended Learning, confluence and continuity and potential scenarios facing the same end: the training.

  3. Effect of the radiolitic sterilization in polyethylene/starch blends

    Directory of Open Access Journals (Sweden)

    Flávia Gonçalves Domingues Ferreira

    2008-01-01

    Full Text Available Samples of LDPE/modified starch blends 80/20 m/m before and after exposure to gamma rays were examined by scanning electron microscopy (SEM, Fourier transform infrared spectroscopy (FTIR and X-ray diffraction. The effect of gamma radiation is clearly seen in the samples irradiated at a dose of 25 kGy. The main alteration in the polymeric material after exposure at the radiation range was a decrease in the mechanical properties, alterations in the chemical structure of the blend with an increase in the carbonyl and vinyl indices and the appearance of new crystalline symmetry generating a crystalline domain not existing before in the blend.

  4. Biodegradation of diesel/biodiesel blends in saturated sand microcosms

    DEFF Research Database (Denmark)

    Lisiecki, Piotr; Chrzanowski, Łukasz; Szulc, Alicja;

    2014-01-01

    The aim of the study was to evaluate the biodegradation extent of both aromatic and aliphatic hydrocarbon fractions in saturated sandy microcosm spiked with diesel/biodiesel blends (D, B10, B20, B30, B40, B50, B60, B70, B80, B90 and B100, where D is commercial petroleum diesel fuel and B is...... commercial biodiesel blend) augmented with a bacterial consortium of petroleum degraders. The biodegradation kinetics for blends were evaluated based on measuring the amount of emitted CO2 after 578 days. Subsequently, the residual aromatic and aliphatic fractions were separated and determined by employing...... GC-FID and GC _ GC–TOF-MS. Additionally, the influence of biodiesel-amendment on the community dynamics was assessed based on the results of real-time PCR analyzes. Our results suggest that the biodegradation extents of both aliphatic and aromatic hydrocarbon were uninfluenced by the addition of...

  5. Tests of blending and correlation of distillate fuel properties

    Science.gov (United States)

    Erwin, J.; Bowden, J. N.

    1982-01-01

    The development of a fuel test matrix, results from tests of several blends of distillate aircraft fuels, and the use of correlations in formulation determination during a NASA-sponsored program to identify new aircraft fuels are described. The program was initiated in order to characterize fuel blends which are appropriate for different types of combustors in use and under development. The fuels were required to feature a specified range of properties. Attention is given to fuel volatility, hydrogen content, aromatic content, freezing point, kinematic viscosity, and naphthalene content. Paraffinic and naphtenic base stocks were employed, using alkyl benzene, naphthene benzenes, and naphthalenes to adjust the blend properties. Categories for the test fuels comprised source-controlled and composition controlled fuels. Test results and compositions of various fuels are provided.

  6. Photophysics of charge transfer in a polyfluorene/violanthrone blend

    Science.gov (United States)

    Cabanillas-Gonzalez, J.; Virgili, T.; Lanzani, G.; Yeates, S.; Ariu, M.; Nelson, J.; Bradley, D. D. C.

    2005-01-01

    We present a study of the photophysical and photovoltaic properties of blends of violanthrone in poly[9, 9-bis (2-ethylhexyl)-fluorene-2, 7-diyl ] (PF2/6) . Photoluminescence quenching and photocurrent measurements show moderate efficiencies for charge generation, characteristic of such polymer/dye blends. Pump-probe measurements on blend films suggest that while ˜47% of the total exciton population dissociates within 4ps of photoexcitation, only ˜32% subsequently results in the formation of dye anions. We attribute the discrepancy to the likely formation of complex species with long lifetimes, such as stabilized interface charge pairs or exciplexes. This conclusion is supported by the appearance of a long lifetime component of 2.4ns in the dynamics of the photoinduced absorption signal associated to polarons in photoinduced absorption bands centered at 560nm .

  7. Evaluation of photodegradation in LDPE/modified starch blends

    Directory of Open Access Journals (Sweden)

    Flávia G. D. Ferreira

    2009-01-01

    Full Text Available Photodegradation of LDPE/modified starch blends 80/20 m/m has been examined by scanning electron microscopy (SEM, Fourier transform infrared spectroscopy (FTIR and X ray diffraction (DRX before and after exposure to ultraviolet radiation (UV. Samples were exposed to UV in the laboratory for periods of 6, 24, 48 and 60 hours. The main alteration in the polymeric material after exposure to the radiation was a decrease in the mechanical properties, tensile strength and elongation. There were also changes in the chemical structure of the blend with an increase in the carbonyl and vinyl indices, 65.58 and 53.29%, respectively. The analysis of the blend crystallinity pointed to the formation of a new crystalline symmetry that did not exist before the irradiation.

  8. Photothermal and morphological characterization of PLA/PCL polymer blends

    Science.gov (United States)

    Correa-Pacheco, Z. N.; Jiménez-Pérez, J. L.; Sabino, M. A.; Cruz-Orea, A.; Loaiza, M.

    2015-09-01

    Nowadays, some synthetic polymers have been replaced by biodegradable polymers in order to avoid environmental contamination. Among these biodegradables polymers, aliphatic polyesters such as polylactic acid (PLA) and polycaprolactone (PCL) have been widely used. In the present study, solvent-casting films of PLA, PCL and polymer blends with and without compatibilizer (PLA grafted with maleic anhydride) were prepared. The thermal diffusivity ( α) of each sample was obtained by using the open photoacoustic cell technique. Morphology and thermal properties were determined by using scanning electron microscopy, transmission electron microscopy and differential scanning calorimetry (DSC), respectively. The blends showed lower thermal diffusivity compared to pure polymers. However, when the compatibilizer was used, the highest value of thermal diffusivity was obtained. Also, cold crystallization with the highest value of enthalpy of fusion was observed for the compatibilized sample, which was revealed by DSC. To our knowledge, this is the first time that the thermal diffusivity of these biodegradable polymer blends is reported.

  9. Study of Blended Learning Process in Education Context

    Directory of Open Access Journals (Sweden)

    Asif Irshad Khan

    2012-09-01

    Full Text Available Education is one of the areas that are experiencing phenomenal changes as a result of the advancement and use of information technology. Mobile and e-learning are already facilitating the teaching and learning experience with the use of latest channels and technologies. Blended learning is a potential outcome of advanced technology based learning system. The charm of blended learning approach lies in the adaptation of technology aided learning methods in addition to the existing traditional based learning. With the introduction of technology, the overall learning as well as teaching experience is considerably enhanced by covering negative aspects of the traditional approach. In this paper a blended learning model for higher education where traditional classroom lectures are supported via e-learning.

  10. Preparation and characterization of blends containing silk fibroin and chitosan

    International Nuclear Information System (INIS)

    The aim of this study was to prepare and characterize blend membranes of silk fibroin and chitosan. Moreover, a conformation of fibroin to a more stable form induced by the addition of chitosan was verified. Blend membranes of fibroin/chitosan were prepared in different proportions and had their crystallinity, structural conformation and thermal stability characterized. The results of crystallographic analysis (XRD) indicated the tendency to higher structural organization caused by the addition of chitosan. FTIR showed that, mainly in a content of chitosan of only 25%, fibroin is present in a more stable form. Thermal analyzes indicate that fibroin is thermally stable and that when its proportion in the blend increases, the temperature in which the degradation is initiated also does so. (author)

  11. Phase behavior of miscible block copolymer blends and baraplastic property

    International Nuclear Information System (INIS)

    The phase behavior of the multi-component polymer systems such as blends and block copolymers (BCPs) has been studied extensively, as it determines the chemical and physical properties of the polymeric materials in practical applications. Above all, polymer baroplasticity is a desirable property for the recycling and regenerating industries, since it allows the polymers to flow at relatively mild pressure. Particularly, the compressibility issue on the enhanced miscibility with pressure has been an attractive topic, because an ordered state of the baroplastic BCPs becomes a phase-mixed state (or disordered phase) between the two dissimilar blocks upon pressurizing. This is in contrast to the incompressibility that was dictated by the enthalpic effect arising from the increased unfavorable contacts between the two blocks by increasing pressure. The phase behaviors of BCP blends composed of the weakly interacting (with no specific interaction) polystyrene-b-poly(n-butyl methacrylate) (PS-b-PnBMA) and deuterated polystyreneb- poly-(n-hexyl methacrylate) (dPS-b-PnHMA) were investigated by Small-Angle Neutron Scattering(SANS) and Depolarized Light Scattering (DPLS) measurements. Interestingly, pressure dependence of various phase transitions for the miscible BCP blends was significantly changed, in which the blends consist of a PS-b-PnBMA and a deuterated dPS-b-PnHMA. To elucidate the origin and difference in baroplasticity of weakly interacting BCP blends, the pressure dependence of transition temperatures was evaluated using enthalpic and volumetric changes at phase transitions. We also demonstrate that the entropic compressibility for the miscible BCP blends is a baroplastic indicator, which was characterized by the negative volume change on mixing (ΔVmix) at transitions.

  12. Certification of alternative aviation fuels and blend components

    Energy Technology Data Exchange (ETDEWEB)

    Wilson III, George R. (Southwest Research Institute, 6220 Culebra Road, San Antonio, Texas 78238 (United States)); Edwards, Tim; Corporan, Edwin (United States Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433 (United States)); Freerks, Robert L. (Rentech, Incorporated, 1331 17th Street, Denver, Colorado 80202 (United States))

    2013-01-15

    Aviation turbine engine fuel specifications are governed by ASTM International, formerly known as the American Society for Testing and Materials (ASTM) International, and the British Ministry of Defence (MOD). ASTM D1655 Standard Specification for Aviation Turbine Fuels and MOD Defence Standard 91-91 are the guiding specifications for this fuel throughout most of the world. Both of these documents rely heavily on the vast amount of experience in production and use of turbine engine fuels from conventional sources, such as crude oil, natural gas condensates, heavy oil, shale oil, and oil sands. Turbine engine fuel derived from these resources and meeting the above specifications has properties that are generally considered acceptable for fuels to be used in turbine engines. Alternative and synthetic fuel components are approved for use to blend with conventional turbine engine fuels after considerable testing. ASTM has established a specification for fuels containing synthesized hydrocarbons under D7566, and the MOD has included additional requirements for fuels containing synthetic components under Annex D of DS91-91. New turbine engine fuel additives and blend components need to be evaluated using ASTM D4054, Standard Practice for Qualification and Approval of New Aviation Turbine Fuels and Fuel Additives. This paper discusses these specifications and testing requirements in light of recent literature claiming that some biomass-derived blend components, which have been used to blend in conventional aviation fuel, meet the requirements for aviation turbine fuels as specified by ASTM and the MOD. The 'Table 1' requirements listed in both D1655 and DS91-91 are predicated on the assumption that the feedstocks used to make fuels meeting these requirements are from approved sources. Recent papers have implied that commercial jet fuel can be blended with renewable components that are not hydrocarbons (such as fatty acid methyl esters). These are not allowed blend

  13. Interdiffusion and Spinodal Decomposition in Electrically Conducting Polymer Blends

    Directory of Open Access Journals (Sweden)

    Antti Takala

    2015-08-01

    Full Text Available The impact of phase morphology in electrically conducting polymer composites has become essential for the efficiency of the various functional applications, in which the continuity of the electroactive paths in multicomponent systems is essential. For instance in bulk heterojunction organic solar cells, where the light-induced electron transfer through photon absorption creating excitons (electron-hole pairs, the control of diffusion of the spatially localized excitons and their dissociation at the interface and the effective collection of holes and electrons, all depend on the surface area, domain sizes, and connectivity in these organic semiconductor blends. We have used a model semiconductor polymer blend with defined miscibility to investigate the phase separation kinetics and the formation of connected pathways. Temperature jump experiments were applied from a miscible region of semiconducting poly(alkylthiophene (PAT blends with ethylenevinylacetate-elastomers (EVA and the kinetics at the early stages of phase separation were evaluated in order to establish bicontinuous phase morphology via spinodal decomposition. The diffusion in the blend was followed by two methods: first during a miscible phase separating into two phases: from the measurement of the spinodal decomposition. Secondly the diffusion was measured by monitoring the interdiffusion of PAT film into the EVA film at elected temperatures and eventually compared the temperature dependent diffusion characteristics. With this first quantitative evaluation of the spinodal decomposition as well as the interdiffusion in conducting polymer blends, we show that a systematic control of the phase separation kinetics in a polymer blend with one of the components being electrically conducting polymer can be used to optimize the morphology.

  14. On The compatibility and dynamic vulcanization of Pom/Nbr blends

    International Nuclear Information System (INIS)

    Polymer blends based on polyacetal butadiene rubber were prepared by melt blending technique. The mixing parameters such ad temperature, time and speed of mixing were varied to obtain a wide range of properties. The mixing parameters were optimized by evaluating the mechanical properties of the blend over a wide range of mixing conditions. The morphology of the blend indicated a two-phase structure. This study describes an attempt to improve the tensile strength of Pom/Nbr blends by means of compatibility and dynamic vulcanization. A commercial compatibility, maleic anhydride (Ma), has been used to control the phase morphology of the blend system. Dicumyl peroxide is used to dynamically vulcanize the Nbr elastomer in the blend. The tensile strength of the compatibility systems showed improvement. Dynamic vulcanization raises elastic recovery and tensile modulus of the blends, but the elongation at break decreases

  15. 40 CFR 418.70 - Applicability; description of the mixed and blend fertilizer production subcategory.

    Science.gov (United States)

    2010-07-01

    ... and blend fertilizer production subcategory. 418.70 Section 418.70 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS FERTILIZER MANUFACTURING POINT SOURCE CATEGORY Mixed and Blend Fertilizer Production Subcategory § 418.70 Applicability; description...

  16. Effect of maleic anhydride on the physico-mechanical properties of NR/PE blends

    International Nuclear Information System (INIS)

    Blending of two or more polymers is considered as a new technique to produce new materials with new properties at low production cost and investment. Rubber / Rubber blends are well known in tire industry. In the last decade rubber and plastic blending attract the interest of many researchers and technologists. In the present work NR and LLDPE was blended in presence of maleic anhydride (MA) on a Brabender premixed at different conditions and namely temperature and time. The obtained blends were cured with sulphur and peroxide curing systems. Peroxide can crosslink both NR and PE, but the sulphur system crosslinks only the rubber phase in the blend. The data showed also that the addition of MA greatly improved the physico-mechanical properties of NR/PE blends. The surface morphology of the blends under investigation was studied by SEM. The results will be presented and discussed in detail

  17. 76 FR 78290 - Cooperative Research and Development Agreement: Usage of Biodiesel Fuel Blends Within Marine...

    Science.gov (United States)

    2011-12-16

    ... Register (73 FR 3316). Cooperative Research and Development Agreements Cooperative Research and Development... SECURITY Coast Guard Cooperative Research and Development Agreement: Usage of Biodiesel Fuel Blends Within... technology enhancements, performance, costs, and other issues associated with using biodiesel fuel blends...

  18. Practical use of mathematical methods for determining the composition of coal blends

    Energy Technology Data Exchange (ETDEWEB)

    Kaziszyn, I. (Instytut Chemicznej Przerobki Wegla, Zabrze, Poland); Lojek, M.; Postrzednik, S.

    1977-12-01

    By applying planned experiment methods relationships were worked out between quality coefficients of coke and the composition of a coal blend. The suitability of this method for blends carbonized in experimental furnaces and under industrial conditions was verified.

  19. Optimal control of blending and melting of copper concentrates

    Science.gov (United States)

    Imanbekova, Ulzhan; Hotra, Oleksandra; Koshimbayev, Shamil; Popiel, Piotr; Tanaś, Jacek

    2015-09-01

    The mathematical models of the melting process, the optimization criterion and constraints on the input and controlling variables and the values of the conductivities of the melt under the electrodes and the phase voltages are used to solve the optimization problem of the electrical regime of the electric furnace. In this paper the optimal variant of the electrical regime of the furnace for the electromelting and blending processing of copper concentrates is considered, which can be provided by the optimal immersion of electrodes. The optimal parameters of the technological process of electromelting and blending are calculated. The proposed mathematical model could be applied for melting process optimization.

  20. Polypropylene-polyethylene blends modified by gamma radiation

    International Nuclear Information System (INIS)

    One way to obtain a better mechanical property of polypropylene and polyethylene is to increasing the number of polymer chains cross-linked by gamma radiation. After irradiation a network is formed as a result of various chemical reactions and the radicals formed are concentrated in the amorphous phase. With the objective to improve the mechanical properties of PP, blends with PE were prepared and irradiated in doses up to 500 kGy, in atmospheric ambient. The molecular characterization of the blends was made by infrared spectroscopy and the data showed an increase in rigidity and a unique behaviour in Izod impact resistance. (author)

  1. Pore structure and carbonation in blended lime-cement pastes

    OpenAIRE

    Álvarez, J. I.; Arandigoyen, M.

    2006-01-01

    The present study aims to gain a fuller understandingof the curing process in lime pastes (100, 90, 80, 70,60, 50 and 40% lime) blended with cement by analyzingcarbonation in these materials. A hydrated, airslaked lime powder and CEM II A/L 32.5 Portlandcement were used for the blends. These materialswere singled out for research primarily because theymay be used in the restoration of heritage monuments.Variation in weight was used as an indicator for carbonation.A new parameter, A, was found...

  2. Blended Learning in Real Estate Education: A Survey

    OpenAIRE

    Thomson, B; Martens, B.

    2015-01-01

    Blended learning is to regarded a didactical meaningful combination of traditional face-to-face instruction and state-of-the-art e-learning formats. The efficiency and flexibility of computer-mediated forms of learning are combined with the social aspects of face-to-face communication. In other words a useful learning arrangement which combines modern-day means of networking through the internet and ‘classical’ learning methods and media. At the time of writing, blended learning has been oper...

  3. Blended Learning与研究生外语教学

    Institute of Scientific and Technical Information of China (English)

    耿静先

    2011-01-01

    Blended Learning(混合式学习)的精髓是把传统课堂教学和多媒体网络教学的优势结合起来.在研究生外语教学中应用Blended Learning理论,就要求在课程设置、教学模式、教学方法和教学评估等方面,把不同的教学要素适时、适地的混合起来,以达到最佳教学效果.

  4. Use of Blended Approach in the Learning of Electromagnetic Induction

    CERN Document Server

    Chew, Charles

    2015-01-01

    This paper traces the importance of pedagogical content knowledge in the digital age to prepare today students for the 21st century. It highlights the need for ICT-based pedagogical models that are grounded in both the learning theories of constructivism and connectivism. One such suitable ICT-based pedagogical model is the TSOI Hybrid Learning Model. By means of a physics blended learning exemplar based on the TSOI Hybrid Learning Model, this paper argues for the use of blended learning approach as the way forward for 21st century teaching.

  5. Characterization of Fibers Produced from Blends of Polybutylene and Polypropylene

    OpenAIRE

    Robert L. Shambaugh, Ph.D; Diana L. Ortiz

    2007-01-01

    Blends of polybutylene (PB-1) and polypropylene were used to produce fibers at spinning speeds of 800-2100 m/min. Concentrations ranged from 0% PP to 100% PP. The stress-strain behavior of the resultant fibers was examined, and the fibers were analyzed for crystallinity via DSC (differential scanning calorimetry). Fibers produced from blends of PB-1/PP show mechanical properties that are in between the properties of the pure polymers. The tensile strength of 50% PB-1 fibers is comparable to t...

  6. Polymer blends for LDB applications. [Long Duration Ballooning

    Science.gov (United States)

    Lichkus, Andrew M.; Harrison, Ian R.

    1991-01-01

    A series of LCP/PE blends have been studied to determine the potential of such systems to produce a high modulus balloon film material which retains the balloon fabrication and low temperature flight advantages of the current PE films. Blown films of blends of 5 and 15 percent LCP in PE have been produced which show a 28 percent enhancement in modulus over the neat PE matrix. These results are substantially lower than anticipated and are explained in terms of the LCP reinforcement aspect ratio and fibril diameter.

  7. Dispersion-strengthened Aluminium Products Manufactured by Powder Blending

    DEFF Research Database (Denmark)

    Hansen, Niels

    1969-01-01

    Detailed experiments carried out to examine relationship between microstructure and mechanical properties of powder-blended aluminum products are reported; their results as well as structural studies by transmission electron microscopy and tensile-and creep- testing, are given; as dispersed phase......, various oxide powders were selected on criterion that during manufacturing no reaction must taken place between metal and oxide phase; strength of powder-blended aluminum products increases and elongation decreases with decreasing particle size of aluminum powder and with increasing concentration of oxide...

  8. HEU to LEU Conversion and Blending Facility: UF6 blending alternative to produce LEU UF6 for commercial use

    International Nuclear Information System (INIS)

    US DOE is examining options for disposing of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials; the nuclear material will be converted to a form more proliferation- resistant than the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. Five technologies for blending HEU will be assessed; blending as UF6 to produce a UF6 product for commercial use is one of them. This document provides data to be used in the environmental impact analysis for the UF6 blending HEU disposition option. Resource needs, employment needs, waste and emissions from plant, hazards, accident scenarios, and intersite transportation are discussed

  9. Blending Learning和信息技术与课程整合%Blending learning and information technology curriculum integration

    Institute of Scientific and Technical Information of China (English)

    董文君

    2006-01-01

    随着对E-learning的研究转入低潮,人们开始冷静思考总结经验教训,于是将传统课堂教育和E-learning的优势相结合,产生了Blending Learning的概念.而现今学校教育中最红火的莫过于信息技术与课程整合,这符合素质教育以及21世纪人才培养目标的要求.本文拟从Blending Learning为信息技术与课程整合带来的新启示这个角度着手,探讨如何将Blending Learning的思想融入课程整合中,以期为整合带来新思路、扩展新道路.

  10. Effect of Variation in Blending Variables on the Properties of CRMB

    Directory of Open Access Journals (Sweden)

    Naeem Aziz Memon

    2016-04-01

    Full Text Available The enhancement in the properties of the modified blends largely depends on the proper understanding of the interaction between CR (Crumb Rubber and bitumen, where the CR particles swell after absorbing lighter fraction from the bitumen phase. However, the properties of CRMB (Crumb Rubber Modified Bitumen blends at a wide range of temperatures are considered to be somewhat unclear due to the various interaction effects of CR and base bitumen. This largely depends on the interaction conditions such as blending time, temperature, speed and device, which may alter the properties of the blend to great extent. In this study, influence of the interaction condition was investigated by looking at the viscosity with a Brookfield viscometer. For this, CR and bitumen proportions along with other material characteristics were kept constant to understand the effect of interaction parameters of the properties of the CRMB blend. A total of 12 CRMB blends were produced with unvarying combinations of material constituents. However, selected variation in the blending parameters were; blending device, duration, speed and temperature. Observations from this laboratory study indicated: (1 blending performed with the high shear mixer resulted in higher viscosity values compared to the blends produced with the low shear mixer; (2 reduced blending time was required to achieve peak and ultimate stable viscosities, when blends were produced with the high shear mixer; (3 blending temperature of 180°C has resulted in the blends with consistent properties for longer blending durations compared to the blends produced at higher temperature. As a result, results with high shear mixer were always promising, which required comparatively lower interaction temperature, time and speed.

  11. Preparation and Characterization of Chitosan/Agar Blended Films: Part 2. Thermal, Mechanical, and Surface Properties

    OpenAIRE

    Elhefian, Esam. A.; Mohamed Mahmoud NASEF; Yahaya, Abdul Hamid

    2012-01-01

    Chitosan/agar (CS/AG) films were prepared by blending different proportions of chitosan and agar (considering chitosan as the major component) in solution forms. The thermal stability of the blended films was studied using thermal gravimetric analysis (TGA). It was revealed that chitosan and agar form a compatible blend. Studying the mechanical properties of the films showed a decrease in the tensile strength and elongation at break with increasing agar content. Blending of agar with chitosan...

  12. Thermal analysis of SEBS blends with phase change material for injection molding

    OpenAIRE

    Peydro, M. A.; Juárez Varón, David; Pérez Bernabeu, Elena; Sellés Cantó, Miguel Ángel

    2014-01-01

    Thermal analysis: Differential Scanning Calorimetry and Thermogravimetric Analysis (DSC and TGA) of SEBS blends with phase change materials (PCMs) have been studied in this paper. SEBS blends were made using two transparent SEBS commercial grades with extreme hardness values. The first thermal property determined in SEBS blends was the evaluation of the thermal degradation at high temperatures DSC. Another thermal property of the SEBS blends consists in knowing the degradation process of the ...

  13. Towards a Blended Learning Model for Teaching and Learning Computer Programming: A Case Study

    OpenAIRE

    Said HADJERROUIT

    2008-01-01

    Blended learning is becoming an attractive model in higher education as new innovative information technologies are becoming increasingly available. However, just blending face-to-face learning with information technologies cannot provide effective teaching and efficient solutions for learning. To be successful, blended learning must rely on solid learning theory and pedagogical strategies. In addition, there is a need for a design-based research approach to explore blending learning through ...

  14. What Is The Hoopla About Blended Learning: Something Old Is New Again

    OpenAIRE

    Hassan Rastegarpour

    2011-01-01

    The recent focus on blended learning has led so many educationalists in corporate training and academia to believe that a new educational phenomenon has been discovered. In reality, the blending of face-to-face instruction with various types of non-classroom technology mediated delivery has been practiced within the academic and non academic environments for more than four decades. Who does really want to know the real story of blended learning? Blended learning sounds like a nice idea- mixi...

  15. Blended learning experience in teacher education: the trainees´ perspective

    OpenAIRE

    Monika Černá

    2009-01-01

    The article deals with blended learning in the context of pre-graduate English language teacher education. Firstly, the concept of blended learning is defined, then, the attention is focused on the online component of a blend, namely on the issue of interpersonal interaction including the challenges, which learning through online networking poses. Finally, results of a small–scale research are provided to offer insights into teacher trainees´ perspective of the blended learning experience at ...

  16. Literature Review in Conceptions and Approaches to Teaching using Blended Learning

    OpenAIRE

    Vicki Caravias

    2015-01-01

    This paper presents a critical review and synthesis of research literature in higher education exploring teachers' conceptions of blended learning and their approaches to both design and teaching. Definitions of blended learning and conceptual frameworks are considered first. Attention is given to Picciano's Blending with Purpose Multimodal framework. This paper builds upon previous research on blended learning and conceptual framework by Picciano (A. Picciano, 2009) by exploring how objectiv...

  17. Development And Testing Of Biogas-Petrol Blend As An Alternative Fuel For Spark Ignition Engine

    OpenAIRE

    Awogbemi; Omojola; Adeyemo,, Adebowale; Sunday Babatunde

    2015-01-01

    Abstract This research is on the development and testing of a biogas-petrol blend to run a spark ignition engine. A2080 ratio biogaspetrol blend was developed as an alternative fuel for spark ignition engine test bed. Petrol and biogas-petrol blend were comparatively tested on the test bed to determine the effectiveness of the fuels. The results of the tests showed that biogas petrol blend generated higher torque brake power indicated power brake thermal efficiency and brake mean effective p...

  18. Anomalous Molecular Weight Dependence of Chain Dynamics in Unentangled Polymer Blends with Strong Dynamic Asymmetry

    OpenAIRE

    Arrese-Igor, Silvia; Alegría, Ángel; Moreno Segurado, Ángel J.; Colmenero de León, Juan

    2011-01-01

    We address the general question of how the molecular weight dependence of chain dynamics in unentangled polymers is modified by blending. By dielectric spectroscopy we measure the normal mode relaxation of polyisoprene in blends with a slower component of poly(ter-butylstyrene). Unentangled polyisoprene in the blend exhibits strong deviations from Rouse scaling, approaching 'entangled-like' behavior at low temperatures in concomitance with the increase of the dynamic asymmetry in the blend. T...

  19. Significant Enhancement of Mechanical and Thermal Properties of Thermoplastic Polyester Elastomer by Polymer Blending and Nanoinclusion

    OpenAIRE

    Manwar Hussain; Young Hui Ko; Yong Ho Choa

    2016-01-01

    Thermoplastic elastomer composites and nanocomposites were fabricated via melt processing technique by blending thermoplastic elastomer (TPEE) with poly(butylene terephthalate) (PBT) thermoplastic and also by adding small amount of organo modified nanoclay and/or polytetrafluoroethylene (PTFE). We study the effect of polymer blending on the mechanical and thermal properties of TPEE blends with and without nanoparticle additions. Significant improvement was observed by blending only TPEE and v...

  20. Modification of hydrophobic polypeptide-based film by blending with hydrophilic poly(acrylic acid)

    OpenAIRE

    Guoquan Zhu; Fagang Wang; Qiaochun Gao; Yuying Liu

    2013-01-01

    In this study, a series of poly(γ-benzyl L-glutamate)/poly(acrylic acid) (PBLG/PAA) polymer blend films were prepared by casting the polymer blend solution in dimethylsulfoxide (DMSO). The structure and morphology of the polymer blend film were investigated by Fourier Transform Infrared Spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM). Thermal, mechanical, and chemical properties of PBLG/PAA polymer blend films were studied by Differential Scanning Calorimetry (DSC), Thermogra...

  1. Evaluation of non-linear blending in dual-energy computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, David R. [Biomedical Imaging Resource, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905 (United States)], E-mail: holmes.david3@mayo.edu; Fletcher, Joel G. [Department of Radiology, Mayo Clinic College of Medicine (United States); Apel, Anja [Siemens Medical Solutions USA, Inc. (United States); Huprich, James E.; Siddiki, Hassan; Hough, David M. [Department of Radiology, Mayo Clinic College of Medicine (United States); Schmidt, Bernhard [Siemens Medical Solutions USA, Inc. (United States); Flohr, Thomas G. [Department of Radiology, Mayo Clinic College of Medicine (United States); Robb, Richard [Biomedical Imaging Resource, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905 (United States); McCollough, Cynthia; Wittmer, Michael [Department of Radiology, Mayo Clinic College of Medicine (United States); Eusemann, Christian [Siemens Medical Solutions USA, Inc. (United States)

    2008-12-15

    Dual-energy CT scanning has significant potential for disease identification and classification. However, it dramatically increases the amount of data collected and therefore impacts the clinical workflow. One way to simplify image review is to fuse CT datasets of different tube energies into a unique blended dataset with desirable properties. A non-linear blending method based on a modified sigmoid function was compared to a standard 0.3 linear blending method. The methods were evaluated in both a liver phantom and patient study. The liver phantom contained six syringes of known CT contrast which were placed in a bovine liver. After scanning at multiple tube currents (45, 55, 65, 75, 85, 95, 105, and 115 mAs for the 140-kV tube), the datasets were blended using both methods. A contrast-to-noise (CNR) measure was calculated for each syringe. In addition, all eight scans were normalized using the effective dose and statistically compared. In the patient study, 45 dual-energy CT scans were retrospectively mixed using the 0.3 linear blending and modified sigmoid blending functions. The scans were compared visually by two radiologists. For the 15, 45, and 64 HU syringes, the non-linear blended images exhibited similar CNR to the linear blended images; however, for the 79, 116, and 145 HU syringes, the non-linear blended images consistently had a higher CNR across dose settings. The radiologists qualitatively preferred the non-linear blended images of the phantom. In the patient study, the radiologists preferred non-linear blending in 31 of 45 cases with a strong preference in bowel and liver cases. Non-linear blending of dual energy data can provide an improvement in CNR over linear blending and is accompanied by a visual preference for non-linear blended images. Further study on selection of blending parameters and lesion conspicuity in non-linear blended images is being pursued.

  2. Studies on the Mechanical and Water uptake Properties of Some Polyolefins / Corn Starch Blends (1)

    OpenAIRE

    Ifeoma Perpetua Oragwu

    2013-01-01

    Corn starch blends of high density- and low density polyethylene have been prepared by injection moulding technique. Maleic anhydrides- graft-polyethylene was used as a compatibilizers. The effect of corn starch content on the blends was evaluated by mechanical property measurements and water uptake tests. Results indicated that the tensile strength of the blends decreased with increase in corn starch contents. While the elongation at break of low density polyethylene-corn starch blends dec...

  3. Sociotechnical Systems Approach: An Internal Assessment of a Blended Doctoral Program

    Science.gov (United States)

    Erichsen, Elizabeth Anne; DeLorme, Lyn; Connelley, Rosalinda; Okurut-Ibore, Christine; McNamara, Lisa; Aljohani, Obaidalah

    2013-01-01

    An internal assessment was conducted utilizing a sociotechnical systems approach and cultural lens as a means of exploring the dynamics of a blended doctoral program. Blended learning environments were conceived of as sociotechnical systems, and blended programs were defined as programs that utilize multimodal means for the mediation of…

  4. Revisiting the Blended Learning Literature: Using a Complex Adaptive Systems Framework

    Science.gov (United States)

    Wang, Yuping; Han, Xibin; Yang, Juan

    2015-01-01

    This research has two aims: (1) to bridge a gap in blended learning research--the lack of a systems approach to the understanding of blended learning research and practice, and (2) to promote a more comprehensive understanding of what has been achieved and what needs to be achieved in blended learning research and practice. To achieve these aims,…

  5. An Empirical Evaluation of Critical Factors Influencing Learner Satisfaction in Blended Learning: A Pilot Study

    Science.gov (United States)

    Chen, Won Sun; Yao, Adrian Yong Tat

    2016-01-01

    Blended learning, a convergence of e-learning approach and face-to-face learning, has been regarded as a new paradigm in modern education. The degree of learners' satisfaction with blended learning played a crucial role in evaluating the effectiveness of blended learning adoption. Therefore, this study examined the primary factors affecting…

  6. Practical experience and results with an advanced on-line gasoline blend optimization system

    Energy Technology Data Exchange (ETDEWEB)

    Serpemen, Y.; Baumeister, K.H.; Hubel, A.; Raichel, P. (Veba Oel Entwicklungs-Gessellschaft mbH, Gelsenkirchen (DE))

    1989-01-01

    Refinery profit margins increased significantly by using the on-line gasoline blend optimization system which allows considerable savings resulting from octane give-away reduction, appreciably enhanced butane utilization, optimum use of the available blend components, and increased operating flexibility by elimination of reblends. The experience with this advanced on-line blending system is described in this paper.

  7. Influence of diblock copolymer on the morphology and properties of polystyrene/poly(dimethylsiloxane) blends

    DEFF Research Database (Denmark)

    Chuai, Chengzhi; Li, Shu; Almdal, Kristoffer;

    2004-01-01

    Blends of polystyrene (PS) and poly(dimethylsiloxane) (PDMS), with and without diblock copolymers (PS-b-PDMS), were prepared by melt mixing. The melt rheology behavior of the blends was studied with a capillary rheometer. The morphology of the blends was examined with scanning electron microscopy...

  8. A Case Study of the Introductory Psychology Blended Learning Model at McMaster University

    Science.gov (United States)

    Sana, Faria; Fenesi, Barbara; Kim, Joseph A.

    2011-01-01

    This paper provides a brief review of blended learning as a didactic method, and discusses the issues and challenges of using blended learning models in post-secondary education. Blended learning refers to mixed modes of instruction that combine traditional face-to-face classroom teaching methods and online learning materials. The paper will…

  9. Transitioning an Adult-Serving University to a Blended Learning Model

    Science.gov (United States)

    Korr, Jeremy; Derwin, Ellen Baker; Greene, Kimberly; Sokoloff, William

    2012-01-01

    While many institutions deliver some classes in blended format, Brandman University transitioned all of its face-to-face classes to blended delivery, using a model tailored to the needs of adult learners. This article provides research supporting the ways that blended learning principles align with key principles of andragogy. The article provides…

  10. Blended Learning: Investigating Its Potential in an English Language Teacher Training Program

    Science.gov (United States)

    Kocoglu, Zeynep; Ozek, Yesim; Kesli, Yesim

    2011-01-01

    Although the benefits of blended learning have been well documented in educational research, relatively few studies have examined blended learning in language teacher education. This study discusses a blended learning approach for a teacher training program designed for in-service English language teachers, and investigates its effectiveness by…

  11. Blended Learning Experience in Teacher Education: The Trainees' Perspective

    Science.gov (United States)

    Cerná, Monika

    2009-01-01

    The article deals with blended learning in the context of pre-graduate English language teacher education. Firstly, the concept of blended learning is defined, then, the attention is focused on the online component of a blend, namely on the issue of interpersonal interaction including the challenges, which learning through online networking poses.…

  12. Effective Blended Learning Practices: Evidence-Based Perspectives in ICT-Facilitated Education

    Science.gov (United States)

    Stacey, Elizabeth, Ed.; Gerbic, Philippa, Ed.

    2009-01-01

    New innovations of online learning within blended environments create a need within academia for research on best practices in teaching. This book provides insight into the practice of blended learning in higher education. This unique book collects new international research into many aspects of blended learning from the perspectives of learners,…

  13. Blended Learning Environments in Higher Education: A Case Study of How Professors Make It Happen

    Science.gov (United States)

    King, Sarah E.; Arnold, Katie Cerrone

    2012-01-01

    Blended learning has become a prominent method of course content delivery in higher education. Researchers have found that motivation, communication, and course design are three factors that contribute to the overall success of blended learning courses and students' satisfaction with blended learning courses. This qualitative study also found that…

  14. Applying TSOI Hybrid Learning Model to Enhance Blended Learning Experience in Science Education

    Science.gov (United States)

    Tsoi, Mun Fie

    2009-01-01

    Purpose: Research on the nature of blended learning and its features has led to a variety of approaches to the practice of blended learning. The purpose of this paper is to provide an alternative practice model, the TSOI hybrid learning model (HLM) to enhance the blended learning experiences in science education. Design/methodology/approach: The…

  15. An Analysis of High Impact Scholarship and Publication Trends in Blended Learning

    Science.gov (United States)

    Halverson, Lisa R.; Graham, Charles R.; Spring, Kristian J.; Drysdale, Jeffery S.

    2012-01-01

    Blended learning is a diverse and expanding area of design and inquiry that combines face-to-face and online modalities. As blended learning research matures, numerous voices enter the conversation. This study begins the search for the center of this emerging area of study by finding the most cited scholarship on blended learning. Using Harzing's…

  16. Development and Validation of the Blended Learning Environment Instrument (BLEI) in Higher Education

    Science.gov (United States)

    Aljahni, Areej; Al-Begain, Khalid; Skinner, Heather

    2014-01-01

    Part of ongoing research into the efficacy of blended learning in higher education within the Kingdom of Saudi Arabia (KSA). The need for, and development of, a Blended Learning Environment Instrument (BLEI) are explained. This new instrument assesses student perceptions across five core aspects of blended learning environments: Infrastructure,…

  17. Educators' Perceptions, Attitudes and Practices: Blended Learning in Business and Management Education

    Science.gov (United States)

    Benson, Vladlena; Anderson, Deborah; Ooms, Ann

    2011-01-01

    Adoption of blended learning is a complex process for higher education institutions and academic staff. Although the move towards blended learning is generally instigated at institutional level, factors determining its success and minimising resistance of faculty often emerge at delivery level. This paper explores adoption of blended learning…

  18. Evaluating Student Satisfaction with Blended Learning in a Gender-Segregated Environment

    Science.gov (United States)

    Naaj, Mahmoud Abou; Nachouki, Mirna; Ankit, Ahmed

    2012-01-01

    Blended learning combines multiple delivery media that are designed to complement each other and promote learning and application-learned behavior (Smith & Dillon, 1999). This article reports on a study conducted in the College of Information Technology to evaluate levels of student' satisfaction with blended learning. The particular blend of…

  19. EFL Secondary School Teachers' Views on Blended Learning in Tabuk City

    Science.gov (United States)

    Alfahadi, Abdulrahman M.; Alsalhi, Abdulrhman A.; Alshammari, Abdullah S.

    2015-01-01

    The aim of this study is to investigate EFL Secondary School Teachers' Views on Blended Learning. It also aims to investigate (a) the teachers' views on blended learning content and process, and (b) how blended learning is effective in developing teachers' performance. The study sample included 35 EFL Saudi teachers in Tabuk City, KSA. In order to…

  20. Global Blended Learning Practices for Teaching and Learning, Leadership and Professional Development

    Science.gov (United States)

    Hilliard, Ann Toler

    2015-01-01

    Blended learning is a combination of online and face-to-face activities for classroom instruction or other training modalities to help develop new knowledge and skills that can be transferred to the workplace environment. The use of blended learning is expanding globally (Vaughn, 2007). Blended learning is evident in professional development…

  1. The Impact of Leadership Support for Blended Learning on Teachers and Students

    Science.gov (United States)

    Bodden-White, Michelle Marie

    2015-01-01

    This quantitative study examined the relationship between teachers' perceptions of leadership support for their use of a blended learning approach to teach math in fourth or fifth grade and their use of blended learning. The study also examined teachers' perceptions of leadership support for incorporating blended learning and student engagement.…

  2. An Integrated Methodology for Design of Tailor-Made Blended Products

    DEFF Research Database (Denmark)

    Yunus, Nor Alafiza; Gernaey, Krist; Woodley, John;

    2012-01-01

    analyzed. Finally, experimental work (or detailed model-based verification) is conducted in stage three to validate the selected blend candidates. In this study, the product design stage is highlighted through a case study of gasoline blends with bio-based chemicals. The objective of this study is to...... identify blended gasoline products that match (or improve) the performance of the conventional gasoline....

  3. Film-forming properties of castor oil polyol ester blends in elastohydrodynamic conditions

    Science.gov (United States)

    The viscosities and elastohydrodynamic (EHD) film thickness properties of binary blends of castor oil with polyol esters were determined experimentally. Predicted blend viscosity was calculated from the viscosity of the pure blend components. Measured viscosity values were closer to the values pre...

  4. Partially fluorinated arylene polyethers and their ternary blend membranes with PBI and H3PO4

    DEFF Research Database (Denmark)

    Kerres, J.; Schonberger, F.; Chromik, A;

    2008-01-01

    ionomer has been blended with poly(2,2'-mphenylene-5,5'-bibenzimidazole) (PBI), yielding base-acid blends with PBI in excess. The base-acid blend membranes have been characterised in terms of solubility in DMAc, water uptake and oxidative stability by immersion in aqueous 5 wt.-% H2O2 solutions and Fenton...

  5. A View of Blended Learning in ELT Perspective%从大学英语教学透视Blended Learning

    Institute of Scientific and Technical Information of China (English)

    赵丽娟

    2004-01-01

    本文从大学英语教学和Blended Learning的产生、发展等多视角透视其概念内涵;在计算机及网络技术已经全面且实质性地应用于我国英语教学的今天,正确地把握Blended Learning的本质将有助于教育技术在英语教学改革中发挥越来越重要的作用.

  6. Parasitic wasp females are attracted to blends of host-induced plant volatiles: do qualitative and quantitative differences in the blend matter? [v1; ref status: indexed, http://f1000r.es/y3

    Directory of Open Access Journals (Sweden)

    Masayoshi Uefune

    2013-02-01

    Full Text Available Naïve Cotesia vestalis wasps, parasitoids of diamondback moth (DBM larvae, are attracted to a synthetic blend (Blend A of host-induced plant volatiles composed of sabinene, n-heptanal, α-pinene, and (Z-3-hexenyl acetate, in a ratio of 1.8:1.3:2.0:3.0. We studied whether qualitative (adding (R-limonene: Blend B or quantitative changes (changing ratios: Blend C to Blend A affected the olfactory response of C. vestalis in the background of intact komatsuna plant volatiles. Naïve wasps showed equal preference to Blends A and B and Blends A and C in two-choice tests. Wasps with oviposition experience in the presence of Blend B preferred Blend B over Blend A, while wasps that had oviposited without a volatile blend showed no preference between the two. Likewise, wasps that had starvation experience in the presence of Blend B preferred Blend A over Blend B, while wasps that had starved without a volatile blend showed no preference between the two. Wasps that had oviposition experience either with or without Blend A showed equal preferences between Blends C and A. However, wasps that had starvation experience in the presence of Blend A preferred Blend C over Blend A, while those that starved without a volatile blend showed equal preferences between the two. By manipulating quality and quantity of the synthetic attractants, we showed to what extent C. vestalis could discriminate/learn slight differences between blends that were all, in principle, attractive.

  7. Parasitic wasp females are attracted to blends of host-induced plant volatiles: do qualitative and quantitative differences in the blend matter? [v2; ref status: indexed, http://f1000r.es/12h

    Directory of Open Access Journals (Sweden)

    Masayoshi Uefune

    2013-04-01

    Full Text Available Naïve Cotesia vestalis wasps, parasitoids of diamondback moth (DBM larvae, are attracted to a synthetic blend (Blend A of host-induced plant volatiles composed of sabinene, n-heptanal, α-pinene, and (Z-3-hexenyl acetate, in a ratio of 1.8:1.3:2.0:3.0. We studied whether qualitative (adding (R-limonene: Blend B or quantitative changes (changing ratios: Blend C to Blend A affected the olfactory response of C. vestalis in the background of intact komatsuna plant volatiles. Naïve wasps showed equal preference to Blends A and B and Blends A and C in two-choice tests. Wasps with oviposition experience in the presence of Blend B preferred Blend B over Blend A, while wasps that had oviposited without a volatile blend showed no preference between the two. Likewise, wasps that had starvation experience in the presence of Blend B preferred Blend A over Blend B, while wasps that had starved without a volatile blend showed no preference between the two. Wasps that had oviposition experience either with or without Blend A showed equal preferences between Blends C and A. However, wasps that had starvation experience in the presence of Blend A preferred Blend C over Blend A, while those that starved without a volatile blend showed equal preferences between the two. By manipulating quality and quantity of the synthetic attractants, we showed to what extent C. vestalis could discriminate/learn slight differences between blends that were all, in principle, attractive.

  8. Blending Classroom Teaching and Learning with QR Codes

    Science.gov (United States)

    Rikala, Jenni; Kankaanranta, Marja

    2014-01-01

    The aim of this case study was to explore the feasibility of the Quick Response (QR) codes and mobile devices in the context of Finnish basic education. The interest was especially to explore how mobile devices and QR codes can enhance and blend teaching and learning. The data were collected with a teacher interview and pupil surveys. The learning…

  9. 40 CFR 80.69 - Requirements for downstream oxygenate blending.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Requirements for downstream oxygenate... downstream oxygenate blending. The requirements of this section apply to all reformulated gasoline blendstock... annual compliance period; (D) A process for notifying oxygenate blenders and other downstream parties...

  10. Fuel and fuel blending components from biomass derived pyrolysis oil

    Science.gov (United States)

    McCall, Michael J.; Brandvold, Timothy A.; Elliott, Douglas C.

    2012-12-11

    A process for the conversion of biomass derived pyrolysis oil to liquid fuel components is presented. The process includes the production of diesel, aviation, and naphtha boiling point range fuels or fuel blending components by two-stage deoxygenation of the pyrolysis oil and separation of the products.

  11. Long fiber reinforcement of polypropylene/polystyrene blends

    NARCIS (Netherlands)

    Inberg, J.P.F.; Hunse, P.H.; Gaymans, R.J.

    1999-01-01

    The recycling of inseparable polymer mixtures usually results in blends with poor mechanical properties. A mixture of PP and PS was taken as a model compound for a recyclate. The effect of adding glass fibers to a mixture of PP/PS (70/30) was studied, with special attention to long glass fiber reinf

  12. Biodiesel/ULSD blend ratios by analysis of fuel properties

    Science.gov (United States)

    Biodiesel is an alternative fuel that is made from vegetable oil or animal fat. Biodiesel is often blended with ultra low sulfur diesel (ULSD; 15 mg/kg maximum sulfur content) in volumetric ratios (VBD) of up to 20 vol% (B20). Government tax credits and other regulatory requirements may depend on ac...

  13. A Blended Learning Scenario to Enhance Learners' Oral Production Skills

    Science.gov (United States)

    Kim, Hee-Kyung

    2015-01-01

    This paper examines the effectiveness of a mobile assisted blended learning scenario for pronunciation in Korean language. In particular, we analyze how asynchronous oral communication between learners of Korean and native speakers via "kakaotalk" (an open source mobile phone application) may be beneficial to the learner in terms of…

  14. Microporous membranes from polyolefin-polyamide blend materials

    Czech Academy of Sciences Publication Activity Database

    Meier-Haack, J.; Valko, M.; Lunkwitz, K.; Bleha, Miroslav

    2004-01-01

    Roč. 163, 1-3 (2004), s. 215-221. ISSN 0011-9164. [Membrane Science and Technology Conference PERMEA 2003. Tatranské Matliare, 07.09.2003-11.09.2003] Institutional research plan: CEZ:AV0Z4050913 Keywords : microporous membranes * polypropylene polyamide blends * reactive extrusion Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.057, year: 2004

  15. Oxidation stability of rapeseed biodiesel/petroleum diesel blends

    DEFF Research Database (Denmark)

    Østerstrøm, Freja From; Anderson, James E.; Mueller, Sherry A.;

    2016-01-01

    oxidation of a biodiesel fuel blend consisting of 30% (v/v) rapeseed methyl ester in petroleum diesel (B30) was conducted at 70 and 90 °C with three aeration rates. Oxidation rates increased with increasing temperature as indicated by decreases in induction period (Rancimat), concentrations of unsaturated...

  16. Corporate Blended Learning in Portugal: Current Status and Future Directions

    Science.gov (United States)

    Marcal, Julia; Caetano, Antonio

    2010-01-01

    The aim of this study is to characterize the current status of blended learning in Portugal, given that b-learning has grown exponentially in the Portuguese market over recent years. 38 organizations (representing 68% of all institutions certified to provide distance training by the Government Labour Office--DGERT-) participated in this study. The…

  17. Design of a Blended Learning Environment: Considerations and Implementation Issues

    Science.gov (United States)

    Gedik, Nuray; Kiraz, Ercan; Ozden, M. Yasar

    2013-01-01

    This study identified critical issues in the design of a blended learning environment by examining basic design considerations and implementation issues. Following a design-based research approach with the phenomenological tradition of qualitative research, the study investigated instructor experiences relating to the design, development, and…

  18. Investigation on Water Jet Treated Polyester/cotton Blended Cambric

    Institute of Scientific and Technical Information of China (English)

    黄故

    2004-01-01

    Analytical examination was made to ascertain the effect of the high pressure water flow on the fabric properties.Polyester/cotton blended cambric was spurted by high pressure water flow. Fabric properties such as handle,thickness, tensile strength , stiffness and air permeability after the water treatment were investigated.

  19. Junction characteristics of C60/polycarbonate blend on Si substrate

    International Nuclear Information System (INIS)

    We report a study of the interface between fullerene (C60) doped polycarbonate (PC) blends and n-type Si substrate. C60 is usually an electron acceptor in interpenetrated networks and an electron transport in photovoltaic cells. We have studied that the guest-host approach to prepare C60 doped polycarbonate blend. In this article, we report the I-V characteristics of C60 doped polycarbonate/n-type Si junction and the annealing effect on these characteristics. In this junction, a nanocomposite of organic semiconductor fullerene (C60), used as the active medium, with an inert polycarbonate matrix was spin coated on n-type Si substrate. We found that the C60 shows the junction characteristics with n-type Si substrate. The knee voltage and dynamic resistance varies with concentration of C60 as well as temperature. Ellipsometry studies showed the annealing effect on the refractive index and thickness of C60 doped polycarbonate blend on n-type Si substrate. The optical micrographs show that fullerene (C60) is spherical molecule and it is blend in the form of crystallites having size of micron order.

  20. Biodiesel/Petrodiesel blends: analytical determination of biodiesel percentage

    International Nuclear Information System (INIS)

    Analysis of biodiesel/petrodiesel blends is of interest both for technical and fiscal reasons. Several methods have been developed to carried out this kind of analysis, most of team based on chromatographic and spectroscopic techniques. Recently, a new method based on natural abundance radiocarbon analysis has been proposed and validated and could be extended for more complex samples

  1. Encapsulated Presentation: A New Paradigm of Blended Learning

    Science.gov (United States)

    Rose, Richard; Ray, Jan

    2011-01-01

    This article is a presentation of a new mode of blended learning whose only goal is to enrich the quality of instruction in the face-to-face classroom through the simultaneous delivery of online and face-to-face components. Encapsulated presentation is the delivery of the entire presentation phase of a lesson in the classroom by electronic methods…

  2. Chitosan/Poly(ɛ-caprolactone) blend scaffolds for cartilage repair

    NARCIS (Netherlands)

    Neves, Sara C.; Moreira Teixeira, Liliana S.; Moroni, Lorenzo; Reis, Rui L.; Blitterswijk, van Clemens A.; Alves, Natália M.; Karperien, Marcel; Mano, João F.

    2011-01-01

    Chitosan (CHT)/poly(ɛ-caprolactone) (PCL) blend 3D fiber-mesh scaffolds were studied as possible support structures for articular cartilage tissue (ACT) repair. Micro-fibers were obtained by wet-spinning of three different polymeric solutions: 100:0 (100CHT), 75:25 (75CHT) and 50:50 (50CHT) wt.% CHT

  3. Funtionality of Sucralose/Maltodextrin: Isomalt blends in Oatmeal Cookies

    Science.gov (United States)

    Functionality of Sucralose/Maltodextrin:Isomalt blends in Oatmeal Cookies Ruthann B. Swanson1, Rebecca McKemie1, Elizabeth M. Savage2 and Hong Zhuang2 1University of Georgia, Athens, GA 30605; 2ARS-USDA, Athens, GA 30605 Availability of reduced-in-sugar baked products with quality characteristics...

  4. Role Taking and Knowledge Building in a Blended University Course

    Science.gov (United States)

    Cesareni, Donatella; Cacciamani, Stefano; Fujita, Nobuko

    2016-01-01

    Role taking is an established approach for promoting social cognition. Playing a specific role within a group could lead students to exercise collective cognitive responsibility for collaborative knowledge building. Two studies explored the relationship of role taking to participation in a blended university course. Students participated in the…

  5. Mapping Cultural Frame Shifting in Interaction Design with Blending Theory

    DEFF Research Database (Denmark)

    Markussen, Thomas; Krogh, Peter Gall

    2008-01-01

    we apply the network model of mental spaces from Fauconnier & Turner's blending theory onto video material and interviews from initial qualitative use studies of a design case. In so doing we explore and argue for how meaning formation and embodied cognition coalesce in cultural frame shifting and...

  6. Preparation, morphology and rheology of thermoplastic starch/polycaprolactone blends

    Czech Academy of Sciences Publication Activity Database

    Šlouf, Miroslav; Ostafinska, Aleksandra; Nevoralová, Martina; Michálková, Danuše; Horák, Pavel; Kredatusová, Jana

    Budapest : Department of Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences, 2015. s. 574-576. [Multinational Congress on Microscopy /12./. 23.08.2015-28.08.2015, Eger] R&D Projects: GA ČR(CZ) GA14-17921S Institutional support: RVO:61389013 Keywords : biodegradable polymers * thermoplastic starch * blends Subject RIV: JJ - Other Materials

  7. Preparing Language Teachers for Blended Teaching of Summary Writing

    Science.gov (United States)

    Yang, Yu-Fen

    2014-01-01

    Research on preparing language teachers for blended teaching of summary writing, a mix of on-site and online instruction for college students to grasp the gist of the texts, is scarce in higher education. This study examined the problems encountered and solutions proposed by six language teachers, who altogether instructed 214 college students on…

  8. Blended Learning in Distance Education: Sri Lankan Perspective

    Science.gov (United States)

    Liyanagunawardena, T. R.; Adams, A. A.; Rassool, N.; Williams, S. A.

    2014-01-01

    The purpose of this paper is to explore the implementation of online learning in distance educational delivery at Yellow Fields University (pseudonymous) in Sri Lanka. The implementation of online distance education at the University included the use of blended learning. The policy initiative to introduce online for distance education in Sri Lanka…

  9. THERMOPLASTIC STARCH-KRAFT LIGNIN-GLYCEROL BLENDS

    Science.gov (United States)

    Starch-kraft lignin-glycerol blends were extruded in a twin-screw extruder to produce non-brittle films. One week after extrusion, films with a mid-range composition of 52% starch, 20% lignin, and 28% glycerol showed a tensile strength at break of 2.8 MPa, Young's modulus of 48 MPa, and elongation ...

  10. Norwegian Nurses’ Experiences with Blended Learning: An Evaluation Study

    Directory of Open Access Journals (Sweden)

    Edda Johansen

    2012-04-01

    Full Text Available An increasing number of nurses undertake continuing education via information and communication technologies. Development of best practice, based on students’ own experiences, is vital in order to create the most effective learning environment. This paper describes the challenges to and facilitators of learning for a group of Norwegian nurses enrolled in a postgraduate course in wound management delivered by blended learning, which combines face-to-face and online components. Data was gathered through a focus group interview and inductive content analysis was used to identify themes emerging from the data. A number of both personal and academic facilitators, and challenges impacted on these adult learners. Technical and academic problems combined with a lack of time created a steep learning curve for these adult students. Valuable feedback, IT support at home and an increased competence eventually gave them a foundation for lifelong learning. Blended learning is an important way to offer postgraduate courses to give adults access to continuing educational programmes independent of geographical location. Both academic and personal challenges and facilitators should be taken into account when educators design blended learning courses in order to facilitate an effective learning environment for adults through the best blend of face-to-face and online learning.

  11. Blended Learning: Communication, Locations and Work-Life Practices

    Science.gov (United States)

    Moe, Carl Erik; Rye, Stale Angen

    2011-01-01

    The article discusses blended learning and how various delivery formats affect the way learning is situated in work-life practices. The authors approached this issue through an empirical study of an in-service training programme for middle-level managers in a number of case organisations. The programme used a combination of e-learning, textbooks…

  12. Partitioning Behavior of Petrodiesel/Biodiesel Blends in Water

    Science.gov (United States)

    The partitioning behavior of six petrodiesel/soybean-biodiesel blends (B0, B20, B40, B60, B80, and B100, where B100 is 100% unblended biodiesel) in water was investigated at various oil loads by the 10-fold dilution method. Five fatty acid methyl esters (FAMEs), C10 - C20 n

  13. Practical Applications and Experiences in K-20 Blended Learning Environments

    Science.gov (United States)

    Kyei-Blankson, Lydia, Ed.; Ntuli, Esther, Ed.

    2014-01-01

    Learning environments continue to change considerably and is no longer confined to the face-to-face classroom setting. As learning options have evolved, educators must adopt a variety of pedagogical strategies and innovative technologies to enable learning. "Practical Applications and Experiences in K-20 Blended Learning Environments"…

  14. Constructs Related to Community College Student Satisfaction in Blended Learning

    Science.gov (United States)

    Sorden, Stephen D.; Munene, Ishmael I.

    2013-01-01

    This paper discusses the constructs of social presence, collaborative learning, computer-supported collaborative learning, and satisfaction in blended learning environments. It presents the results of a study that used the Collaborative Learning, Social Presence, and Satisfaction (CLSS) questionnaire, which was conducted on one campus in a…

  15. Blended Learning in Higher Education: Three Different Design Approaches

    Science.gov (United States)

    Alammary, Ali; Sheard, Judy; Carbone, Angela

    2014-01-01

    Blended learning has been growing in popularity as it has proved to be an effective approach for accommodating an increasingly diverse student population whilst adding value to the learning environment through incorporation of online teaching resources. Despite this growing interest, there is ongoing debate about the definition of the concept of…

  16. Transforming K-12 Rural Education through Blended Learning: Teacher Perspectives

    Science.gov (United States)

    Kellerer, Paula; Kellerer, Eric; Werth, Eric; Werth, Lori; Montgomery, Danielle; Clyde, Rozella; Cozart, Joe; Creach, Laura; Hibbard, Laura; LaFrance, Jason; Rupp, Nadine; Walker, Niki; Carter, Theresa; Kennedy, Kathryn

    2014-01-01

    A qualitative study exploring rural teacher perspectives on the impact of blended learning on students and teachers was conducted in Idaho during the Fall of 2013. Researchers from Northwest Nazarene University's DOCEO Center in partnership with Idaho Digital Learning Academy (IDLA) and the International Association for K-12 Online Learning…

  17. Virtual reality training versus blended learning of laparoscopic cholecystectomy

    DEFF Research Database (Denmark)

    Nickel, Felix; Brzoska, Julia Anja; Gondan, Matthias;

    2015-01-01

    Objective: This study compared virtual reality (VR) training with low cost blended learning (BL) in a structured training program. Background: Training of laparoscopic skills outside the operating room is mandatory to reduce operative times and risks. Methods: Laparoscopy-naïve medical students...

  18. iNACOL Blended Learning Teacher Competency Framework

    Science.gov (United States)

    Powell, Allison; Rabbitt, Beth; Kennedy, Kathryn

    2014-01-01

    In recent years there has been a dramatic rise in interest and early adoption of blended learning to improve the educational experiences of students. A great amount of work has been done to codify approaches, with tools and resources emphasizing the structural components of new models, such as the configuration of physical learning space, use of…

  19. Course Management Systems and Blended Learning: An Innovative Learning Approach

    Science.gov (United States)

    Chou, Amy Y.; Chou, David C.

    2011-01-01

    This article utilizes Rogers' innovation-decision process model (2003) and Beckman and Berry's innovation process model (2007) to create an innovative learning map that illustrates three learning methods (i.e., face-to-face learning, online learning, and blended learning) in two types of innovation (i.e., incremental innovation and radical…

  20. Blended Learning: Instructional Design Strategies for Maximizing Impact

    Science.gov (United States)

    Adams, Jean

    2013-01-01

    Although e-learning has improved in quality, reach and learning impact over the past decade, it can be argued that it has not yet lived up to its potential to transform workplace learning. In the drive to increase effectiveness, interest has grown in blended learning, an instructional strategy that combines the use of web-technologies with more…

  1. Conditioning Factors for Group Management in Blended Learning Scenarios

    OpenAIRE

    Pérez-Sanagustín, Mar; Hernández-Leo, Davinia; Blat, Josep

    2009-01-01

    Pérez-Sanagustín, M., Hernández-Leo D., & Blat, J. (accepted). Conditioning Factors for Group Management in Blended Learning Scenarios. The 9th IEEE International Conference on Advanced Learning Technologies. July, 14-18, 2009, Riga, Latvia.

  2. Team Learning and Collaboration between Online and Blended Learner Groups

    Science.gov (United States)

    Lim, Doo Hun; Yoon, Seung Won

    2008-01-01

    In an effort to compare team-level learning performance resulting from different instructional variables and settings, this study examined how online and blended delivery learner groups compared in terms of learning outcomes, collaboration, and perceived quality of instructional variables. Results indicated that the two teams were not different in…

  3. Alternative Assessment Techniques for Blended and Online Courses

    Science.gov (United States)

    Litchfield, Brenda C.; Dempsey, John V.

    2013-01-01

    Alternative assessment techniques are essential for increasing student learning in blended and online courses. Rather than simply answer multiple-choice questions, students can choose activities in an academic contract. By using a contract, students will be active participants in their own learning. Contracts add a dimension of authenticity to…

  4. An on-line gasoline blending system put into production

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Anew system for online gasoline blending, which was developed by researchers from the CAS Institute of Automation (CASIA), has been put into production at China Petrochemical Corporation (SINOPEC) and PetroChina Corporation. It is expected to thoroughly renovate the technology in this regard and achieve maximal economic benefits in oil production stage.

  5. Performance Test of Engine Fuelled With Diesel and Ethanol Blends.

    Directory of Open Access Journals (Sweden)

    B.K.L.Murthy

    2015-04-01

    Full Text Available Environmental concerns and limited amount of petroleum fuels have caused interests in the development of alternative fuels for internal combustion (ICengines. As an alternative, biodegradable and renewable fuel, ethanol is receiving increasing attention. An experimental investigation on the application of the blends of ethanol with diesel to a diesel engine was carried out. First the solubility of ethanol and diesel was conducted with and without the additive of normal butanol (n-butanol. The purpose of this project is to find the optimum percentage of ethanol that gives simultaneously better performance and lower emissions. The experiments were conducted on a water-cooled single-cylinder Direct Injection (DI diesel engine using 0% (neat diesel fuel, 10% (E10-D, 15%(E15–D, 20% (E20–D, and 25%(E25–D ethanol–diesel blended fuels. Experimental tests were carried out to study the performance of the engine fuelled with the blends compared with those fuelled by diesel. The test results show that it is feasible and applicable for the blends with n-butanol to replace pure diesel as the fuel for diesel engine.

  6. A Pedagogical Model for Science Education through Blended Learning

    NARCIS (Netherlands)

    Bidarra, José; Rusman, Ellen

    2015-01-01

    This paper proposes a framework to support science education through blended learning, based on a participatory and interactive approach supported by ICT-based tools, called Science Learning Activities Model (SLAM). The study constitutes a work in progress and started as a response to complex societ

  7. OXIDATIVE STABILITY OF BIODIESEL/JET FUEL BLENDS

    Science.gov (United States)

    Biodiesel, an alternative fuel made from transesterification of vegetable oil with methanol, is becoming more readily available for use in blends with conventional diesel fuel for transportation applications. Biodiesel has fuel properties comparable to those of conventional diesel fuel and is known...

  8. Microstructure and micromechanical properties of PP/HDPE/EPDM blends

    Czech Academy of Sciences Publication Activity Database

    Šitum, Ana; Nevoralová, Martina; Šlouf, Miroslav; Vranjes, N.; Rek, V.

    Prague: Czechoslovak Microscopy Society, 2014. MS-6-P-2125. ISBN 978-80-260-6720-7. [International Microscopy Congress /18./. 07.09.2014-12.09.2014, Prague] R&D Projects: GA TA ČR TE01020118 Institutional support: RVO:61389013 Keywords : polymer blends * microhardness * microcreep Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  9. Physicochemical, microbiological and sensory evaluation of a bioactive food blend

    Directory of Open Access Journals (Sweden)

    Rosângela dos Santos Ferreira

    2014-09-01

    Full Text Available The potential of functional foods to decrease the risks of chronic non-communicable diseases has motivated the development of products with beneficial effects on fat and carbohydrate metabolism. The present study aimed at analyzing the physicochemical, microbiological, and sensory properties of a bioactive food blend developed to help the nutritional therapy provided to hypolipidemic and hyperglycemic patients with HIV/AIDS treated with antiretroviral therapy. The food blend was evaluated for moisture, protein, carbohydrate, fats, fixed mineral residue, total fiber content, and fatty acid composition, according to the standards established by the Instituto Adolfo Lutz. Food safety was assessed by microbiological analyses for Bacillus cereus, Salmonella spp, and coliforms. Sensory acceptance and intention to purchase were also evaluated. The food blend showed good nutritional potential, with low atherogenicity and thrombogenicity indexes, good macronutrient balance, and high energy value. The adoption of Good Manufacturing Practices (GMP resulted in a product suitable for consumption. With respect to sensory aspects, the food blend showed satisfactory indexes of acceptability and promising marketing potential.

  10. A family of quasi-cubic blended splines and applications

    Institute of Scientific and Technical Information of China (English)

    SU Ben-yue; TAN Jie-qing

    2006-01-01

    A class of quasi-cubic B-spline base functions by trigonometric polynomials are established which inherit properties similar to those of cubic B-spline bases. The corresponding curves with a shape parameter α, defined by the introduced base functions, include the B-spline curves and can approximate the B-spline curves from both sides. The curves can be adjusted easily by using the shape parameter α, where dpi(α,t) is linear with respect to dα for the fixed t. With the shape parameter chosen properly,the defined curves can be used to precisely represent straight line segments, parabola segments, circular arcs and some transcendental curves, and the corresponding tensor product surfaces can also represent spherical surfaces, cylindrical surfaces and some transcendental surfaces exactly. By abandoning positive property, this paper proposes a new C2 continuous blended interpolation spline based on piecewise trigonometric polynomials associated with a sequence of local parameters. Illustration showed that the curves and surfaces constructed by the blended spline can be adjusted easily and freely. The blended interpolation spline curves can be shape-preserving with proper local parameters since these local parameters can be considered to be the magnification ratio to the length of tangent vectors at the interpolating points. The idea is extended to produce blended spline surfaces.

  11. Training Phoneme Blending Skills in Children with Down Syndrome

    Science.gov (United States)

    Burgoyne, Kelly; Duff, Fiona; Snowling, Maggie; Buckley, Sue; Hulme, Charles

    2013-01-01

    This article reports the evaluation of a 6-week programme of teaching designed to support the development of phoneme blending skills in children with Down syndrome (DS). Teaching assistants (TAs) were trained to deliver the intervention to individual children in daily 10-15-minute sessions, within a broader context of reading and language…

  12. Developing ICT Competency for Thai Teachers through Blended Training

    Science.gov (United States)

    Akarawang, Chaiya; Kidrakran, Pachoen; Nuangchalerm, Prasart

    2016-01-01

    The purpose of this study aims to enhance teachers' ICT competency. Three hundred and thirty seven teachers are surveyed through a questionnaire to identify training problems and training needs. Then the blended training model is implemented with teachers. The result showed that it can increase score in cognitive and attitude tests. The post-test…

  13. Blends of caprolactam/caprolactone copolymers and chlorinated polymers

    NARCIS (Netherlands)

    Alberda van Ekenstein, G.O.R.; Deuring, H.; ten Brinke, G.; Ellis, T.S.

    1997-01-01

    The phase behaviour of blends of chlorinated polyethylene, polyvinyl chloride (PVC) and chlorinated PVC with random copolymers of caprolactone and caprolactam has been investigated and the results correlated with a binary interaction model. The known miscibility of polycaprolactone in the chlorinate

  14. Pressure and temperature effects in homopolymer blends and diblock copolymers

    DEFF Research Database (Denmark)

    Frielinghaus, H.; Schwahn, D.; Mortensen, K.;

    1997-01-01

    Thermal composition fluctuations in homopolymer mer blends and diblock copolymers were studied with SANS in varying pressure and temperature fields. For homopolymers we find a quite consistent behavior: The dominating effect of compressibility or packing leads to a reduction of the entropic...

  15. Compatibilization of All-Conjugated Polymer Blends for Organic Photovoltaics.

    Science.gov (United States)

    Lombeck, Florian; Sepe, Alessandro; Thomann, Ralf; Friend, Richard H; Sommer, Michael

    2016-08-23

    Compatibilization of an immiscible binary blend comprising a conjugated electron donor and a conjugated electron acceptor polymer with suitable electronic properties upon addition of a block copolymer (BCP) composed of the same building blocks is demonstrated. Efficient compatibilization during melt-annealing is feasible when the two polymers are immiscible in the melt, i.e. above the melting point of ∼250 °C of the semicrystalline donor polymer P3HT. To generate immiscibility at these high temperatures, the acceptor polymer PCDTBT is equipped with fluorinated side chains leading to an increased Flory-Huggins interaction parameter. Compatibilization in bulk and thin films is demonstrated, showing that the photovoltaic performance of pristine microphase separated and nanostructured BCPs can also be obtained for compatibilized blend films containing low contents of 10-20 wt % BCP. Thermodynamically stable domain sizes range between several tens of microns for pure blends and ∼10 nm for pure block copolymers. In addition to controlling domain size, the amount of block copolymer added dictates the ratio of edge-on and face-on P3HT crystals, with compatibilized films showing an increasing amount of face-on P3HT crystals with increasing amount of compatibilizer. This study demonstrates the prerequisites and benefits of compatibilizing all-conjugated semicrystalline polymer blends for organic photovoltaics. PMID:27482842

  16. Study of the Blending Efficiency of Pitched Blade Impellers

    Directory of Open Access Journals (Sweden)

    I. Fořt

    2001-01-01

    Full Text Available This paper presents an analysis of the blending efficiency of pitched blade impellers under a turbulent regime of flow of an agitated low viscous liquid. The conductivity method is used to determine of the blending (homogenization time of miscible liquids in pilot plant mixing equipment with standard radial baffles. For the given homogeneity degree (98 % a three-blade pitched blade impeller is tested with various off-bottom clearances, vessel/ impeller diameter ratios and various impeller pitch angles. The experimental results show in accordance with theoretical data from the literature, that the greatest effect on the dimensionless blending time is exhibited by the vessel/ impeller diameter ratio and the impeller pitch angle. The number of total circulations necessary for reaching the chosen homogeneity degree depends on the impeller pitch angle and amounts more than three. Finally, the energetic efficiency of the blending process is calculated. The results of this study show, that the highest energetic efficiency of the three-blade pitched blade impeller appears for the pitch angle a = 24°, the impeller/vessel diameter ratio T/D = 2 and the impeller off-bottom clearance h/D = 1.

  17. Blended University Teaching Using Virtual Learning Environments: Conceptions and Approaches

    Science.gov (United States)

    Lameras, Petros; Levy, Philippa; Paraskakis, Iraklis; Webber, Sheila

    2012-01-01

    This paper reports findings from a phenomenographic investigation into blended university teaching using virtual learning environments (VLEs). Interviews with 25 Computer Science teachers in Greek universities illuminated a spectrum of teachers' conceptions and approaches from "teacher-focused and content-oriented", through "student-focused and…

  18. Pressure and temperature effects in homopolymer blends and diblock copolymers

    DEFF Research Database (Denmark)

    Frielinghaus, H.; Schwahn, D.; Mortensen, K.;

    1997-01-01

    fluctuations. Phase boundaries, the Flory-Huggins interaction parameter and the Ginzburg number were obtained. The packing of the molecules changes with pressure. Therefore, the degree of thermal fluctuation as a function of packing and temperature was studied. While in polymer blends packing leads, in some...

  19. PREPARATION OF CARBON NANOFIBERS BY POLYMER BLEND TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The polymer blend technique is a novel method to produced carbon nanofibers. In this paper, we have prepared fine carbon fibers and porous carbon materials by this technique, and we will discuss the experiment results by means of SEM, TGA, Element Analysis, etc.

  20. A Blended Approach to Canadian First Nations Education

    Science.gov (United States)

    Sacher, Martin; Sacher, Mavis; Vaughan, Norman

    2014-01-01

    The purpose of this research study was to investigate if and how a blended approach to Canadian First Nations education could be used to foster student engagement and success. The study examined the SCcyber E-Learning Community program (2012) through the lens of the "Seven Principles of Effective Teaching" (Chickering & Gamson,…

  1. Blended Learning in Biochemistry Education: Analysis of Medical Students' Perceptions

    Science.gov (United States)

    Wardenski, Rosilaine de Fatima; de Espindola, Marina Bazzo; Struchiner, Miriam; Giannella, Tais Rabetti

    2012-01-01

    The objective of this study was to analyze first-year UFRJ medical students' perceptions about the implementation of a blended learning (BL) experience in their Biochemistry I course. During the first semester of 2009, three Biochemistry professors used the Constructore course management system to develop virtual learning environments (VLEs) for…

  2. Linear low density polyethylene/cycloolefin copolymer blends

    Czech Academy of Sciences Publication Activity Database

    Dorigato, A.; Pegoretti, A.; Fambri, L.; Lonardi, C.; Šlouf, Miroslav; Kolařík, Jan

    2011-01-01

    Roč. 5, č. 1 (2011), s. 23-37. ISSN 1788-618X R&D Projects: GA ČR GA106/09/1348 Institutional research plan: CEZ:AV0Z40500505 Keywords : polymer blends * cycloolefin copolymer * creep Subject RIV: JI - Composite Materials Impact factor: 1.769, year: 2011

  3. Dependences between properties of coals, coal blends, and coke

    Energy Technology Data Exchange (ETDEWEB)

    Heilpern, S. (Instytut Chemicznej Przerobki Wegla, Zabrze, Poland); Kaziszyn, I.; Zarembinska, J.; Postrzednik, S.

    1976-12-01

    Investigations were made on charge coals representative for home conditions with the aim of determining the degree of additivity for selected assessment indices of raw material quality. A functional dependence was found between strength indices of coke and those characterizing the coal blend on changing the correlation coefficient r/sup 2/ from 0.70 to 0.48.

  4. A spatial-temporal-spectral blending model using satellite images

    Science.gov (United States)

    Zhang, L.; Fu, D.; Sun, X.; Chen, H.; She, X.

    2016-04-01

    Due to the budget and technical limitations, remote sensing sensor designs trade spatial resolution, swath width and spectral resolution. Consequently, no sensor can provide high spatial resolution, high temporal resolution and high spectral resolution simultaneously. However, the ability of Earth observation at fine resolution is urgently needed for global change science. One possible solution is to “blend” the reflectance from a variety of satellite data sources, including those providing high spatial resolution and less frequent coverage (e.g., Landsat Thematic Mapper, TM), daily global data (e.g., Moderate Resolution Imaging Spectroradiometer, MODIS), and high spectral resolution and infrequent revisit cycle (e.g., Hyperion). However, the previous algorithms for blending multi-source remotely sensed data have some shortcomings, especially with regard to hyperspectral information. This study has developed a SPAtial-Temporal-Spectral blending model (SPATS) that can simulate surface reflectance with high spatial-temporal-spectral resolution. SPATS is based on an existing spatial-temporal image blending model and a spatial-spectral image blending model. The performance of SPATS was tested with both simulated and observed satellite data, using Landsat TM, Hyperion and MODIS data, as well as heterogeneous landscapes as examples. The results show that the high spatial-temporal-spectral resolution reflectance data can be applied to investigations of global landscapes that are changing at different temporal scales.

  5. Identification of Telomerase-activating Blends From Naturally Occurring Compounds.

    Science.gov (United States)

    Ait-Ghezala, Ghania; Hassan, Samira; Tweed, Miles; Paris, Daniel; Crynen, Gogce; Zakirova, Zuchra; Crynen, Stefan; Crawford, Fiona

    2016-06-01

    Context • Telomeres are repeated deoxyribonucleic acid (DNA) sequences (TTAGGG) that are located on the 5' ends of chromosomes, and they control the life span of eukaryotic cells. Compelling evidence has shown that the length of a person's life is dictated by the limited number of times that a human cell can divide. The enzyme telomerase has been shown to bind to and extend the length of telomeres. Thus, strategies for activating telomerase may help maintain telomere length and, thus, may lead to improved health during aging. Objective • The current study intended to investigate the effects of several natural compounds on telomerase activity in an established cell model of telomere shortening (ie, IMR90 cells). Design • The research team designed an in vitro study. Setting • The study was conducted at Roskamp Institute in Sarasota, FL, USA. Intervention • The tested single compounds were (1) α-lipoic acid, (1) green tea extract, (2) dimethylaminoethanol L-bitartrate (DMAE L-bitartrate), (3) N-acetyl-L-cysteine hydrochloride (HCL), (4) chlorella powder, (5) L-carnosine, (6) vitamin D3, (7) rhodiola PE 3%/1%, (8) glycine, (9) French red wine extract, (10) chia seed extract, (11) broccoli seed extract, and (12) Astragalus (TA-65). The compounds were tested singly and as blends. Outcome Measures • Telomerase activity for single compounds and blends of compounds was measured by the TeloTAGGG telomerase polymerase chain reaction (PCR) enzyme-linked immunosorbent assay (ELISA). The 4 most potent blends were investigated for their effects on cancer-cell proliferation and for their potential effects on the cytotoxicity and antiproliferative activity of a chemotherapeutic agent, the topoisomerase I inhibitor topotecan. The benefits of 6 population doublings (PDs) were measured for the single compounds, and the 4 blends were compared to 3 concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Results • Certain of the compounds increased

  6. Performance of jatropha oil blends in a diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Forson, F.K.; Oduro, E.K.; Hammond-Donkoh, E. [Kwame Nkrumah University of Science and Technology, Kumasi (Ghana). Dept. of Mechanical Engineering

    2004-06-01

    Results are presented on tests on a single-cylinder direct-injection engine operating on diesel fuel, jatropha oil, and blends of diesel and jatropha oil in proportions of 97.4%/2.6%; 80%120%; and 50%150% by volume. The results covered a range of operating loads on the engine. Values are given for the chemical and physical properties of the fuels, brake specific fuel consumption, brake power, brake thermal efficiency, engine torque, and the concentrations of carbon monoxide, carbon dioxide and oxygen in the exhaust gases. Carbon dioxide emissions were similar for all fuels, the 97.4% diesel/2.6% jatropha fuel blend was observed to be the lower net contributor to the atmospheric level. The trend of carbon monoxide emissions was similar for the fuels but diesel fuel showed slightly lower emissions to the atmosphere. The test showed that jatropha oil could be conveniently used as a diesel substitute in a diesel engine. The test further showed increases in brake thermal efficiency, brake power and reduction of specific fuel consumption for jatropha oil and its blends with diesel generally, but the most significant conclusion from the study is that the 97.4% diesel/2.6% jatropha fuel blend produced maximum values of the brake power and brake thermal efficiency as well as minimum values of the specific fuel consumption. The 97.4%12.6% fuel blend yielded the highest cetane number and even better engine performance than the diesel fuel suggesting that jatropha oil can be used as an ignition- accelerator additive for diesel fuel. (author)

  7. Miscibility and Morphology of Poly(lactic ACID)/POLY(Β-HYDROXYBUTYRATE) Blends

    Science.gov (United States)

    Tri Phuong, Nguyen; Guinault, Alain; Sollogoub, Cyrille

    2011-01-01

    The miscibility and morphology of poly(lactic)acid (PLA)/polyβ-hydroxybutyrate (PHB) prepared by melt blending method were investigated by Fourier transform infrared (FTIR), Differential scanning calorimetry (DSC), melt rheology and scanning electron microscopy (SEM) observations. FTIR and DSC methods present some limits to examine the miscibility state of PLA/PHB blends. This drawback can be overcome with the Cole-Cole method by observing the η" = f(η') curves to confirm the miscibility of semicrystalline PLA/ semicrystalline PHB blends. MEB micrographs of fractured surface of blends were also used to investigate the miscibility of these blends.

  8. Determination of gel content and SEM morphology for sago-PVA blends film

    International Nuclear Information System (INIS)

    Blends of polyvinyl alcohol and sago starch have been prepared to evaluate the potential of producing biodegradable products. Glycerol was introduced in the blends to improve the flexibility of the films as plasticizer in order more flexible film. These blends have been subjected to electron beam irradiation to evaluate and characterized radiation effect on the blends. Subsequently films were produced from this blend. The gel content of un-irradiated and irradiated films as evidence of cross linking was measured and discussed. This paper also discuss the films morphology from Scanning Electron Microscopy(SEM) observation. (Author)

  9. Design of tailor-made chemical blend using a decomposition-based computer-aided approach

    DEFF Research Database (Denmark)

    Yunus, Nor Alafiza; Gernaey, Krist; Manan, Z.A.;

    2011-01-01

    design methodology for blended liquid products that identifies a set of feasible chemical blends. The blend design problem is formulated as a Mixed Integer Nonlinear Programming (MINLP) model where the objective is to find the optimal blended gasoline or diesel product subject to types of chemicals and...... selection. The application of this systematic and computer-aided approach is illustrated through a case study involving the design of blends of gasoline with oxygenated compounds resulting from degradation and fermentation of biomass for use in internal combustion engines. Emphasis is given here on the...

  10. STUDY ON THE BLENDS OF NYLON 66 AND LIQUID CRYSTALLINE POLYESTERS

    Institute of Scientific and Technical Information of China (English)

    Zhang Shufan; Ren Jinghong

    1991-01-01

    Blends of polyamide (Nylon 66 ) with two different kinds of liquid crystalline polyesters were studied in all the composition range. Homogeneous samples were obtained by coprecipitation from 2wt%. solution of blends. The thermal properties, crystallinity and morphology of these blends were studied by using DSC, polarizing microscopy, and scanning electron microscopy. The phase transition and morphology of the blends are markedlyinfluenced by the composition of liquid crystalline polyesters. The mechanical behaviour of PHB/HNA-Nylon 66 blend was improved .although polyamide (Nylon 66)with the liquid crystalline polyesters were incompatible, but a rather strong interaction between the polymers did exist.

  11. Morphology, thermal and mechanical properties of PVC/MMT nanocomposites prepared by solution blending and solution blending + melt compounding

    DEFF Research Database (Denmark)

    Madaleno, Liliana Andreia Oliveira; Schjødt-Thomsen, Jan; Pinto, José Cruz

    2010-01-01

    Two types of montmorillonite (MMT), natural sodium montmorillonite (Na-MMT) and organically modified montmorillonite (OMMT), in different amounts of 1, 2, 5, 10 and 25 phr (parts per hundred resin), were dispersed in rigid poly (vinyl chloride) by two different methods solution blending and...

  12. HEU to LEU conversion and blending facility: Oxide blending alternative to produce LEU oxide for commercial use

    International Nuclear Information System (INIS)

    The United States Department of Energy (DOE) is examining options for the disposition of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials. Disposition is a process of use or disposal of material that results in the material being converted to a form that is substantially and inherently more proliferation-resistant than the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. This document provides data to be used in the environmental impact analysis for the oxide blending HEU disposition option. This option provides for a yearly HEU throughput of 1 0 metric tons (MT) of uranium metal with an average U235 assay of 50% blended with 165 MT of natural assay triuranium octoxide (U3 O8) per year to produce 177 MT of 4% U235 assay U3 O8, for LWR fuel. Since HEU exists in a variety of forms and not necessarily in the form to be blended, worst case scenarios for preprocessing prior to blending will be assumed for HEU feed streams

  13. Investigation on thermal, mechanical and morphological properties of epoxy/UHWPE blends

    Directory of Open Access Journals (Sweden)

    Shahryar Pashaei

    2010-12-01

    Full Text Available Epoxy/ultrahigh molecular weight polyethylene (UHMWPE blends have been prepared by in-situ polymerization method. The effects of UHMWPE from 2.5 wt % to 10 wt % on the tensile properties of blends have been studied. Tensile properties of blends are characterized and were shown that content 10% UHMWPE was effected on performance of polymer blends significantly. Thermal characteristics of the polymer blends were determined by using differential scanning calorimetry (DSC and thermogravimetric analysis (TGA. TGA thermogram indicated that increased thermal stability of blends after incorporation of UHMWPE. The DSC was shown that Tg of polymer blends increased. The enthalpy of melting (rHm obtained from DSC curves was increased with increase in UHMWPE content in epoxy matrix, due to depend on UHMWPE content in blend systems. The rheology of polymer was envisaged by DMA is affected on the polymer blend. The incorporation of UHMWPE increased mechanical properties of blends. Degradation kinetic parameters have been calculated for thermal degradation processes using two mathematical models namely, Coats-Redfern and Broido’s methods. Morphological behaviour of fractured blends has been studied using scanning electron microscopy (SEM.

  14. Rheological Behavior of Immiscible PS/LDPE Blends: A Comparative Study of the Palierne Emulsion Model

    Directory of Open Access Journals (Sweden)

    Chatchai KUNYAWUT

    2015-02-01

    Full Text Available The rheological behavior of polystyrene (PS/low density polyethylene (LDPE blends have been investigated. Blends with 10, 20 and 30 wt% LDPE were prepared using a co-rotating twin-screw extruder at a melt mixing temperature of 180°C. SEM micrographs revealed that all blends exhibited droplet-type dispersion morphology. Rheological measurements were performed at the same temperature as the mixing temperature. The complex viscosity of the blends laid between those of the PS and the LDPE and decreased with increasing LDPE concentration. The plots of tand of blends with 10 and 20 wt% LDPE suggested that the elasticity of these blends was comparable to that of the pure PS. By contrast, the elasticity behavior of the blend with 30 wt% LDPE was shown to be similar to that of LDPE. Palierne model predictions were in very good agreement with the experimental data for the blends having 10 and 20 wt% LDPE. For the 30 wt% LDPE blend, agreement with the prediction and the experimental data was not as good. Within the frequency range of the rheological measurements, the second plateau at low frequency which results from an increase of the elasticity was not observed in any of the blends studied. This is expected to be due to the long relaxation times of the relatively large LDPE droplets of these blends.

  15. Poly (trimethylene) terephthalate/m-LLDPE blend nanocomposites: Evaluation of mechanical, thermal and morphological behavior

    International Nuclear Information System (INIS)

    PTT/m-LLDPE blends and its nanocomposites were prepared using melt blending technique in a batch mixer. Organically modified nanoclays have been used as nanoscale reinforcement to prepare blend nanocomposites. Mechanical tests revealed optimum performance characteristics at PTT/m-LLDPE ratio of 70:30. Further, incorporation of nanoclays showed higher tensile strength and modulus in the blend nanocomposites as compared to optimized blend. The nanocomposites formation has been established through X-ray diffraction and transmission electron microscopy. The thermal measurements have been carried out using DSC and TGA. DSC thermograms revealed a maximum increase in the crystallization temperature in the presence of clays in the blend system containing Cloisite 30B. TGA thermograms indicated that the thermal stability of the blend increases with the incorporation of nanoclays. DMA measurements reveal that the Cloisite 30B nanocomposite has maximum modulus as compared to other nanocomposites.

  16. Conversion and Blending Facility highly enriched uranium to low enriched uranium as oxide. Revision 1

    International Nuclear Information System (INIS)

    This Conversion and Blending Facility (CBF) will have two missions: (1) convert HEU materials into pure HEU oxide and (2) blend the pure HEU oxide with depleted and natural uranium oxide to produce an LWR grade LEU product. The primary emphasis of this blending operation will be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. To the extent practical, the chemical and isotopic concentrations of blended LEU product will be held within the specifications required for LWR fuel. Such blended LEU product will be offered to the United States Enrichment Corporation (USEC) to be sold as feed material to the commercial nuclear industry. Otherwise, blended LEU will be produced as a waste suitable for storage or disposal

  17. Phase Behavior, Thermal Stability and Rheological Properties of PPEK/PC Blends

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Phase behavior, thermal stability and rheological properties of the blends of poly(phthalazinone ether ketone) (PPEK)with bisphenol-A polycarbonate (PC) prepared by solution coprecipitation were studied using differential scanning calorimetry (DSC), Frourier-Transform IR spectroscopy (FT-IR), thermogravimetric analysis (TGA) and capillary rheometer. The DSC results indicated that PPEK/PC blends are almost immiscible in full compositions. FT-IR investigation showed that there were no apparent specific interactions between the constituent polymers. The blends keep excellent thermal stability and the addition of PC degrades the thermal stability of blends to some degree. The thermal degradation processes of the blends are much similar to that of PC. The studies on rheological properties of blends show that blending PPEK with PC is beneficial to reducing the melt viscosity and improving the appearance of PPEK.

  18. Structural characterization and properties of konjac glucomannan/curdlan blend films.

    Science.gov (United States)

    Wu, Chunhua; Peng, Shuhui; Wen, Chengrong; Wang, Xiumei; Fan, Linlin; Deng, Ronghua; Pang, Jie

    2012-06-20

    A series of novel edible blend films of konjac glucomannan (KGM) and curdlan were prepared by a solvent-casting technique with different blending ratios of the two polymers. The Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), etc. were used to characterize the change of structure and properties of blend films. The results showed that the strong intermolecular hydrogen bonds took place between KGM and curdlan. And the interaction of the blend film was much greater than that of the others when the KGM content in the blend films was around 70 wt% (KC7), resulting in excellent miscibility. The conclusion of the electron tensile testing analysis indicated that the blend film KC7 showed the maximum tensile strength (42.93±1.92 MPa). In addition, the blend films displayed excellent moisture barrier properties, which had a potential application in the food field. PMID:24750750

  19. THE HANDBOOK OF BLENDED LEARNING:Global Perspectives, Local Designs

    Directory of Open Access Journals (Sweden)

    Reviewed by Alev ATES

    2009-10-01

    Full Text Available THE HANDBOOK OF BLENDED LEARNING:Global Perspectives, Local Designs Curtis J. Bonk (ed. and Charles R. Graham (ed., Jay Cross (Foreword,Micheal G. Moore Foreword ISBN: 978-0-7879-7758-0 Publisher: John Wiley & Sons, Inc. Pfeiffer Pages: 624 March 2006.Reviewed by Alev ATESPhD Student at Curriculum and Instruction,Lecturer at Computer Education and Instructional Technologies,Faculty of Education, Ege University, Izmir, TURKEYBlended learning or blended e-learning sounds like aconfusing term at first since it is relatively a new term fortoday‘s instructors. However, Moore reports that it can betraced as far back as the 1920s which was called ―supervisedcorrespondence study‖. For clarification of the term ―blendedlearning‖ and informing the instructors about its commonpractices worldwide, the book provides readers a comprehensive resource about blended learning. It aims to raise awareness of adopting BL from institutional perspectives of many chapter authors from Australia, Korea, Malaysia, the UK, Canada and South Africa who are distinguished people mostly in instructional technology era. With this book, I guess the editors aim at both showing the big picture at macro level and present micro level examples which provide details of blended learning applications among their strengths and weaknesses. As introduced in the book, one ofthe editors Curtis J. Bonk, a former corporate controller and CPA, is now professor of educational psychology as well as instructional systems technology at Indiana University; the other editor Charles R. Graham is an assistant professor of instructionalpsychology and technology at Brigham Young University with a focus on technologymediated teaching and learning.The book is of eight parts including 39 chapters besides two forewords. Therefore, theorganization of this review is considered to take a holistic view for each parts while emphasizing the original and/or impressive aspects that chapter authors provided

  20. The effects of gamma radiation and electron beam on the mechanical properties of polypropylene dominant natural rubber blend

    International Nuclear Information System (INIS)

    The effects of irradiation, with dose ranging from 20 to 100 kGy on the mechanical properties of polypropylene and natural rubber blends (PP/NR blends) were investigated. Crosslinking of the PP/NR blends proved to play a major role in the improvement of the mechanical properties of the blend. The results also revealed that the blend composition the enhancement in properties depend on the irradiation dose and on the concentration of the crosslinking agent. (author)