15 CFR 785.3 - Initiation of administrative proceedings.

Science.gov (United States)

2010-01-01

... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Initiation of administrative proceedings. 785.3 Section 785.3 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE ADDITIONAL PROTOCOL REGULATIONS...

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...

A dark brown roast coffee blend is less effective at stimulating gastric acid secretion in healthy volunteers compared to a medium roast market blend.

Science.gov (United States)

Rubach, Malte; Lang, Roman; Bytof, Gerhard; Stiebitz, Herbert; Lantz, Ingo; Hofmann, Thomas; Somoza, Veronika

2014-06-01

Coffee consumption sometimes is associated with symptoms of stomach discomfort. This work aimed to elucidate whether two coffee beverages, containing similar amounts of caffeine, but differing in their concentrations of (β) N-alkanoyl-5-hydroxytryptamides (C5HTs), chlorogenic acids (CGAs), trigonelline, and N-methylpyridinium (N-MP) have different effects on gastric acid secretion in healthy volunteers. The intragastric pH after administration of bicarbonate with/without 200 mL of a coffee beverage prepared from a market blend or dark roast blend was analyzed in nine healthy volunteers. Coffee beverages were analyzed for their contents of C5HT, N-MP, trigonelline, CGAs, and caffeine using HPLC-DAD and HPLC-MS/MS. Chemical analysis revealed higher concentrations of N-MP for the dark brown blend (87 mg/L) compared to the market blend coffee (29 mg/L), whereas concentrations of C5HT (0.012 versus 0.343 mg/L), CGAs (323 versus 1126 mg/L), and trigonelline (119 versus 343 mg/L) were lower, and caffeine concentrations were similar (607 versus 674 mg/mL). Gastric acid secretion was less effectively stimulated after administration of the dark roast blend coffee compared to the market blend. Future studies are warranted to verify whether a high ratio of N-MP to C5HT and CGAs is beneficial for reducing coffee-associated gastric acid secretion. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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…

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.

PLA and two components silicon rubber blends aiming for frozen foods packaging applications

Science.gov (United States)

Meekum, Utai; Khiansanoi, Apichart

2018-03-01

Designing of PLA and two components silicone rubber blends was studies. Frozen food packaging application is the main ultimate aim. The statistical method using 23 DOE was conducted. The standard testing methods, in particular impact testing at sub-zero temperature, were performed. The preliminary blend formula comprised 1.0 phr of silane and polyester polyols, respectively, was initially resolved. Then, the optimize the silicone portion in the blends was determined. Blending formula using 8.0 phr of silicone with respect to PLA matrix gave rise to the overall satisfactory properties. 3. TETA was used as the silicone curing agent and reactively blended onto the ingredients. TETA at 0.4 phr, with respect to the silicone, enhanced the mechanical properties, especially flexibility and toughness, of the PLA/silicone blend. Exceeding the optimal TETA loading would cause the chain scission and also the dilution effects. Hence, marginal inferior properties of the blends were be experienced. The preliminary biodegradability investigation found that the PLA/silicone blend initially triggered at the second week. Its degradation rate was likely to be faster than neat PLA.

PLA and two components silicon rubber blends aiming for frozen foods packaging applications

Directory of Open Access Journals (Sweden)

Utai Meekum

2018-03-01

Full Text Available Designing of PLA and two components silicone rubber blends was studies. Frozen food packaging application is the main ultimate aim. The statistical method using 23 DOE was conducted. The standard testing methods, in particular impact testing at sub-zero temperature, were performed. The preliminary blend formula comprised 1.0 phr of silane and polyester polyols, respectively, was initially resolved. Then, the optimize the silicone portion in the blends was determined. Blending formula using 8.0 phr of silicone with respect to PLA matrix gave rise to the overall satisfactory properties. 3. TETA was used as the silicone curing agent and reactively blended onto the ingredients. TETA at 0.4 phr, with respect to the silicone, enhanced the mechanical properties, especially flexibility and toughness, of the PLA/silicone blend. Exceeding the optimal TETA loading would cause the chain scission and also the dilution effects. Hence, marginal inferior properties of the blends were be experienced. The preliminary biodegradability investigation found that the PLA/silicone blend initially triggered at the second week. Its degradation rate was likely to be faster than neat PLA. Keywords: PLA/silicone blends, Mechanical properties, Sub-zero impact strength

77 FR 5027 - Food and Drug Administration Transparency Initiative: Exploratory Program To Increase Access to...

Science.gov (United States)

2012-02-01

...] Food and Drug Administration Transparency Initiative: Exploratory Program To Increase Access to the... entitled ``Food and Drug Administration Transparency Initiative: Exploratory Program to [[Page 5028

Radiation crosslinking of polymer blends

International Nuclear Information System (INIS)

Spenadel, L.

1979-01-01

Rocked by the one-two punch of rising energy costs and tougher pollution controls, a growing number of companies are looking to radiation crosslinking as a cheaper, cleaner alternative to heat and costly chemical crosslinking agents such as peroxides. With the development of larger, more powerful electron beam machines it is now possible to irradiate parts as thick as 400 mils in a single pass. Two application areas which have been investigated at our laboratory are the electron beam processing of thermoplastic elastomeric automotive parts and EPDM electrical insulation. This paper covers work carried out to develop the necessary technology base for the radiation crosslinking of ethylene propylene/polyolefin blends. Initial results indicate that EP/PE blends of electrical insulation quality cross-link quite readily when irradiated. On the other hand, EP/PP blends developed for automotive fascia require the addition of crosslinking monomers such as trimethylol propane trimethacrylate in order for crosslinking to predominate over chain scission. Crosslinking EP/PP blends improve mar resistance, flexural set and deformation at elevated temperatures. These are all key properties for automotive fascia. (author)

On the Factors Influencing New Ventures’ Blended Values

DEFF Research Database (Denmark)

Giones, Ferran; Ungerer, Christina; Baltes, Guido

Mullen 2007). These so-called hybrid organizations try to be congruent with their blended values, despite being under external pressure in the process of maturing the new venture (Mcmullen & Warnick 2016). This research explores not only the initial motivations of the entrepreneur as potential influence...... on the ventures’ blended values, but also the source of finance. A dataset of 4,125 early-stage ventures (Entrepreneurship Database Program; Emory University) has been explored to gain insights into how entrepreneurs' motives and external financing sources could influence on the impact dimensions being addressed...... or environmental impact dimensions – thus they may have been willing to adapt their initial goals to match with different donors’ expectations. In the case of social impact ambitions, increasing profit margin targets and venture age have a negative effect on the prevalence of blended values. The research results...

Studies of PVC/ENR blends: blend compositions

International Nuclear Information System (INIS)

Chantara Thevy Ratnam; Khairul Zaman Mohd Dahlan; Nasir, M.; Baharin, A.

2002-01-01

Blends of poly(vinyl chloride/epoxidized natural rubber (PVC/ENR) were prepared by using Bra bender Plasticorder at compositions ranging from 0-100% PVC. They were blended at 150 degree C mixing temperature, 50 rpm rotor speed and 10 minutes mixing time. The blends were characterized for tensile strength , elongation at break, glass transition temperatures and Fourier transform infra red spectroscopy (FTIR). Results revealed that as the PVC content increases the blend behaviour changes from elastomeric to glassy. However the blends found to be compatible at all compositions. (Author)

Minor Theft: Problems of the Initiation of a Case on an Administrative Offense and Conducting an Administrative Investigation

Directory of Open Access Journals (Sweden)

Oleg Y. Filippov

2016-11-01

Full Text Available The paper defines the problem of the initiation of an administrative case and conducting an administrative investigation on cases of identifying signs of minor theft under Art. 7.27 of the Code of Administrative Offences of the Russian Federation in cases where the identity of the offender at the time of committing minor theft is not established, this person is not detained. Guidance on the application of this provision under the existing legislation and on amendments and supplements to the law on administrative offenses is offered.

22 CFR 103.7 - Initiation of administrative enforcement proceedings.

Science.gov (United States)

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Initiation of administrative enforcement proceedings. 103.7 Section 103.7 Foreign Relations DEPARTMENT OF STATE ECONOMIC AND OTHER FUNCTIONS... papers and documentary evidence must be submitted in English. (h) Waiver. The failure of the respondent...

At same leucine intake, a whey/plant protein blend is not as effective as whey to initiate a transient post prandial muscle anabolic response during a catabolic state in mini pigs.

Directory of Open Access Journals (Sweden)

Aurélia Revel

Full Text Available Muscle atrophy has been explained by an anabolic resistance following food intake and an increase of dietary protein intake is recommended. To be optimal, a dietary protein has to be effective not only to initiate but also to prolong a muscle anabolic response in a catabolic state. To our knowledge, whether or not a dairy or a dairy/plant protein blend fulfills these criterions is unknown in a muscle wasting situation.Our aim was, in a control and a catabolic state, to measure continuously muscle anabolism in term of intensity and duration in response to a meal containing casein (CAS, whey (WHEY or a whey/ plant protein blend (BLEND and to evaluate the best protein source to elicit the best post prandial anabolism according to the physio-pathological state.Adult male Yucatan mini pigs were infused with U-13C-Phenylalanine and fed either CAS, WHEY or BLEND. A catabolic state was induced by a glucocorticoid treatment for 8 days (DEX. Muscle protein synthesis, proteolysis and balance were measured with the hind limb arterio-venous differences technique. Repeated time variance analysis were used to assess significant differences.In a catabolic situation, whey proteins were able to initiate muscle anabolism which remained transient in contrast to the stimulated muscle protein accretion with WHEY, CAS or BLEND in healthy conditions. Despite the same leucine intake compared to WHEY, BLEND did not restore a positive protein balance in DEX animals.Even with WHEY, the duration of the anabolic response was not optimal and has to be improved in a catabolic state. The use of BLEND remained of lower efficiency even at same leucine intake than whey.

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.

Relationship between compatibilizer and yield strength of PLA/PP Blend

Science.gov (United States)

Jariyakulsith, Pattanun; Puajindanetr, Somchai

2018-01-01

The aim of this research is to study the relationship between compatibilizer and yield strength of polylactic acid (PLA) and polypropylene (PP) blend. The PLA is blended with PP (PLA/PP) at the ratios of 70/30, 50/50 and 30/70. In addition, (1) polypropylene grafted maleic anhydride (PP-g-MAH) as a compatibilizer at 0.3 and 0.7 part per hundred of PLA/PP resin (phr) and (2) dicumyl peroxide (DCP) being an initiator at 0.03 and 0.07 phr are added in each composition. Yield strength is characterized to study the interaction between compatibilizer, initiator and yield strength by using experimental design of multilevel full factorial. The results show that (1) the yield strength of PLA/PP blend are increased after addition of compatibilizer. Because the adding of PP-g-MAH and DCP resulted in improving compatibility between PLA and PP. (2) there are interaction between PP-g-MAH and DCP that have affected the final properties of PLA/PP blend. The highest yield strength of 27.68 MPa is provided at the ratio of 70/30 blend by using the 0.3 phr of PP-g-MAH and 0.03 phr of DCP. Linear regression model is fitted and follow the assumptions of normal distribution.

Study of a composite from reactive blending of methylol urea resin ...

African Journals Online (AJOL)

This study was designed to study some physical properties of a composite derivable from reactive blending of methylol urea resin (MUR) with natural rubber (NR). Formaldehyde emission, decreased with increase in NR concentration in the blend. Elongation at break and viscosity recorded an initial increase but gradually ...

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.

76 FR 61366 - Food and Drug Administration Transparency Initiative: Draft Proposals for Public Comment to...

Science.gov (United States)

2011-10-04

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2009-N-0247] Food and Drug Administration Transparency Initiative: Draft Proposals for Public Comment to Increase...: Food and Drug Administration, HHS. [[Page 61367

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

DEFF Research Database (Denmark)

Yunus, Nor Alafiza Binti

property values are verified by means of rigorous models for the properties and the mixtures. Besides the methodology, as the main contribution, specific supporting tools that were developed to perform each task are also important contributions of this research work. The applicability of the developed...... important in daily life, since they not only keep people moving around, but also guarantee that machines and equipment work smoothly. The objective of this work is to tackle the blending problems using computer-aided tools for the initial stage of the product design. A systematic methodology for design...... 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....

Blended learning

DEFF Research Database (Denmark)

Dau, Susanne

2016-01-01

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......) instead of the learning processes behind. Much of the existing research within the field seems to miss this perspective. The consequence is a lack of acknowledgement of the driven forces behind the context and the instructional design limiting the knowledge foundation of learning in blended learning. Thus...

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.

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.

Utilization of waste expanded polystyrene: Blends with silica-filled natural rubber

International Nuclear Information System (INIS)

Sekharan, Renju Vaikathusseril; Abraham, Beena Thattekatt; Thachil, Eby Thomas

2012-01-01

Highlights: ► Tensile strength of the silica filled blend is comparable with silica filled NR. ► Modulus and compression set were the best for compatibilized NR/EPS blends. ► Tear strength has increased by 25% for compatibilized blends. ► A 5% waste EPS can be incorporated into NR compounds as a waste management measure. -- Abstract: Expanded polystyrene (EPS) constitutes a considerable part of thermoplastic waste in the environment in terms of volume. In this study, this waste material has been utilized for blending with silica-reinforced natural rubber (NR). The NR/EPS (35/5) blends were prepared by melt mixing in a Brabender Plasticorder. Since NR and EPS are incompatible and immiscible a method has been devised to improve compatibility. For this, EPS and NR were initially grafted with maleic anhydride (MA) using dicumyl peroxide (DCP) to give a graft copolymer. Grafting was confirmed by Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy. This grafted blend was subsequently blended with more of NR during mill compounding. Morphological studies using Scanning Electron Microscopy (SEM) showed better dispersion of EPS in the compatibilized blend compared to the noncompatibilized blend. By this technique, the tensile strength, elongation at break, modulus, tear strength, compression set and hardness of the blend were found to be either at par with or better than that of virgin silica filled NR compound. It is also noted that the thermal properties of the blends are equivalent with that of virgin NR. The study establishes the potential of this method for utilising waste EPS.

Study of observed broad dielectric relaxation and compatibility of polysulfone - Polyvinylidenefluoride blends

Science.gov (United States)

Patel, Swarnim; Shrivas, Sandhya; Dubey, R. K.; Keller, J. M.

2018-05-01

Short circuit thermally stimulated depolarization current measurement techniques has been employed to investigate the dielectric relaxation behavior of PSF: PVDF blends. The samples taken were blends of composition PSF: PVDF:: 80:20; 85:15; 90:10 and 95:05 percent by weight. The thermograms were characterized by a high value of initial current, a low temperature peak around 75-80°C and a prominent broad peak in the temperature interval 130 to 160°C. The two polymers are found to form compatible blend in the studied composition range.

Relations between blended learning possibilities and teachers' approaches to blended learning

DEFF Research Database (Denmark)

Stenalt, Maria Hvid; Nielsen, Tobias Alsted; Bager-Elsborg, Anna

Higher Education has embraced blended learning as a way of enhancing quality in teaching and helping students to learn. This presentation addresses relations between blended learning possiblities presented to teachers in a teacher training project and teachers’ approaches to blended learning. We...... suggest that in order to identify the level of impact of integrating technologies in teaching and learning, we need to understand the factors influencing approaches to design of courses for blended contexts. Participants in the teacher training project come from the Department of Law at Aarhus University......: • Optain locally-embedded knowledge about blended learning • Develop opportunities for law students to receive (more) feedback • Comply with strategic aims The results so far suggest that teachers provide a disciplinary perspective on the key dimensions of blended learning, which influences...

BIODIESEL BLENDS IN SPACE HEATING EQUIPMENT

International Nuclear Information System (INIS)

KRISHNA, C.R.

2001-01-01

Biodiesel is a diesel-like fuel that is derived from processing vegetable oils from various sources, such as soy oil, rapeseed or canola oil, and also waste vegetable oils resulting from cooking use. Brookhaven National laboratory initiated an evaluation of the performance of blends of biodiesel and home heating oil in space heating applications under the sponsorship of the Department of Energy (DOE) through the National Renewable Energy Laboratory (NREL). This report is a result of this work performed in the laboratory. A number of blends of varying amounts of a biodiesel in home heating fuel were tested in both a residential heating system and a commercial size boiler. The results demonstrate that blends of biodiesel and heating oil can be used with few or no modifications to the equipment or operating practices in space heating. The results also showed that there were environmental benefits from the biodiesel addition in terms of reductions in smoke and in Nitrogen Oxides (NOx). The latter result was particularly surprising and of course welcome, in view of the previous results in diesel engines where no changes had been seen. Residential size combustion equipment is presently not subject to NOx regulation. If reductions in NOx similar to those observed here hold up in larger size (commercial and industrial) boilers, a significant increase in the use of biodiesel-like fuel blends could become possible

Blended Learning

NARCIS (Netherlands)

Van der Baaren, John

2009-01-01

Van der Baaren, J. (2009). Blended Learning. Presentation given at the Mini symposium 'Blended Learning the way to go?'. November, 5, 2009, The Hague, The Netherlands: Netherlands Defence Academy (NDLA).

Equilibrating high-molecular-weight symmetric and miscible polymer blends with hierarchical back-mapping

Science.gov (United States)

Ohkuma, Takahiro; Kremer, Kurt; Daoulas, Kostas

2018-05-01

Understanding properties of polymer alloys with computer simulations frequently requires equilibration of samples comprised of microscopically described long molecules. We present the extension of an efficient hierarchical backmapping strategy, initially developed for homopolymer melts, to equilibrate high-molecular-weight binary blends. These mixtures present significant interest for practical applications and fundamental polymer physics. In our approach, the blend is coarse-grained into models representing polymers as chains of soft blobs. Each blob stands for a subchain with N b microscopic monomers. A hierarchy of blob-based models with different resolution is obtained by varying N b. First the model with the largest N b is used to obtain an equilibrated blend. This configuration is sequentially fine-grained, reinserting at each step the degrees of freedom of the next in the hierarchy blob-based model. Once the blob-based description is sufficiently detailed, the microscopic monomers are reinserted. The hard excluded volume is recovered through a push-off procedure and the sample is re-equilibrated with molecular dynamics (MD), requiring relaxation on the order of the entanglement time. For the initial method development we focus on miscible blends described on microscopic level through a generic bead-spring model, which reproduces hard excluded volume, strong covalent bonds, and realistic liquid density. The blended homopolymers are symmetric with respect to molecular architecture and liquid structure. To parameterize the blob-based models and validate equilibration of backmapped samples, we obtain reference data from independent hybrid simulations combining MD and identity exchange Monte Carlo moves, taking advantage of the symmetry of the blends. The potential of the backmapping strategy is demonstrated by equilibrating blend samples with different degree of miscibility, containing 500 chains with 1000 monomers each. Equilibration is verified by comparing

Polymer blends

Energy Technology Data Exchange (ETDEWEB)

Allen, Scott D.; Naik, Sanjeev

2017-08-22

The present invention provides, among other things, extruded blends of aliphatic polycarbonates and polyolefins. In one aspect, provided blends comprise aliphatic polycarbonates such as poly(propylene carbonate) and a lesser amount of a crystalline or semicrystalline polymer. In certain embodiments, provided blends are characterized in that they exhibit unexpected improvements in their elongation properties. In another aspect, the invention provides methods of making such materials and applications of the materials in applications such as the manufacture of consumer packaging materials.

Preparation and characterization of blends containing silk fibroin and chitosan

International Nuclear Information System (INIS)

Moraes, Mariana A. de; Nogueira, Grinia M.; Weska, Raquel F.; Beppu, Marisa M.

2009-01-01

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)

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....

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.

Tough blends of polylactide and castor oil.

Science.gov (United States)

Robertson, Megan L; Paxton, Jessica M; Hillmyer, Marc A

2011-09-01

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.

Blended E-Learning Acceptance as Smart Pedagogical Tools: An Initial Study in Malaysia

Science.gov (United States)

Wong, Kung-Teck; Hamzah, Mohd Sahandri Gani; Goh, Pauline Swee Choo; Yeop, Mohd Azli B.

2016-01-01

The use of technology in classrooms has been considered as the solution to social, economic and educational problems since its introduction to education in mid-1970. There have been many studies conducted on the different aspects of the use of technology in teaching and learning. However, study on teaching with Blended Learning in teaching and…

Polystyrene/Hyperbranched Polyester Blends and Reactive Polystyrene/Hyperbranched Polyester Blends

National Research Council Canada - National Science Library

Mulkern, Thomas

1999-01-01

.... In this work, the incorporation of HBPs in thermoplastic blends was investigated. Several volume fractions of hydroxyl functionalized hyperbranched polyesters were melt blended with nonreactive polystyrene (PS...

Evaluation of ternary blended cements for use in transportation concrete structures

Science.gov (United States)

Gilliland, Amanda Louise

This thesis investigates the use of ternary blended cement concrete mixtures for transportation structures. The study documents technical properties of three concrete mixtures used in federally funded transportation projects in Utah, Kansas, and Michigan that used ternary blended cement concrete mixtures. Data were also collected from laboratory trial batches of ternary blended cement concrete mixtures with mixture designs similar to those of the field projects. The study presents the technical, economic, and environmental advantages of ternary blended cement mixtures. Different barriers of implementation for using ternary blended cement concrete mixtures in transportation projects are addressed. It was concluded that there are no technical, economic, or environmental barriers that exist when using most ternary blended cement concrete mixtures. The technical performance of the ternary blended concrete mixtures that were studied was always better than ordinary portland cement concrete mixtures. The ternary blended cements showed increased durability against chloride ion penetration, alkali silica reaction, and reaction to sulfates. These blends also had less linear shrinkage than ordinary portland cement concrete and met all strength requirements. The increased durability would likely reduce life cycle costs associated with concrete pavement and concrete bridge decks. The initial cost of ternary mixtures can be higher or lower than ordinary portland cement, depending on the supplementary cementitious materials used. Ternary blended cement concrete mixtures produce less carbon dioxide emissions than ordinary portland cement mixtures. This reduces the carbon footprint of construction projects. The barriers associated with implementing ternary blended cement concrete for transportation projects are not significant. Supplying fly ash returns any investment costs for the ready mix plant, including silos and other associated equipment. State specifications can make

Fracture studies of poly(propylene)/elastomer blend with β-form nucleating agent

International Nuclear Information System (INIS)

Bai Hongwei; Wang Yong; Zhang Danli; Xiao Chengquan; Song Bo; Li Yanli; Han Liang

2009-01-01

Poly(propylene)/elastomer blends with β-form nucleating agent (β-NA) aryl amides compound (TMB-5) were prepared. The effects of β-NA on crystallization, melting behaviors and elastomer morphologies of PP/elastomer blends were studied through polarization optical microscope (POM), differential scanning calorimetry (DSC) and scanning electronic microscope (SEM). The fracture behaviors, including notched Izod impact fracture and single-edge notched tensile (SENT) fracture, were comparatively studied to establish the role of NA in improving the fracture toughness of PP/elastomer blends. Our results showed that the presence of β-NA leads to determinable β-PP formation in the blends, and as a consequence the fracture toughness of the blend is improved dramatically. Compared with notched Izod impact testing, which can efficiently characterize the fracture toughness of the blends only at lower elastomer content, SENT testing provides more detail of fracture behavior in all the compositions. Furthermore, SENT test shows that the significant improvement in fracture toughness of PP/elastomer/β-NA is contributed to the simultaneous enhancement of crack initiation energy and crack propagation energy, but largely dominated by crack propagation stage.

12 CFR 505.4 - Administrative appeal of initial determination to deny records.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Administrative appeal of initial determination to deny records. 505.4 Section 505.4 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF.... Appeals may be delivered personally to FOIA Appeals, Office of Thrift Supervision, 1700 G Street, NW...

Blended Learning and Student Satisfaction: An Investigation into an EAP Writing Course

Directory of Open Access Journals (Sweden)

Zainab Ibrahim Abbas

2018-02-01

Full Text Available This paper investigates students satisfaction in a blended English writing course for Academic Purposes in Iraq. Blended learning is a novel mode of approaching education and learning in Iraq so it is very relevant to attempt to determine what factors can help it its success. Its novelty comes not from its use of online platforms such as Moodle but blending the traditional face-to face approach and distance teaching in a way that foster critical thinking and ongoing participation of the students. Different factors were emphasized and investigated regarding satisfaction, among them, the instructor-student and student-student interaction, in addition to the pedagogical aspect of the course. Student’s background such as their job and age and family status were not considered in this study. A modified questionnaire of student’s satisfaction in an online course was used to determine the approximate of satisfaction. The result of the research helped the administration office to apply some improvements to the newly-founded Blended courses in Iraq.

Profiling Student Behaviour in a Blended Course: Closing the Gap Between Blended Teaching and Blended Learning

NARCIS (Netherlands)

Bos, Nynke; Brand-Gruwel, Saskia

2018-01-01

Blended learning is often associated with student-oriented learning in which students have varying degrees of control over their learning process. However, the current notion of blended learning is often a teacher- oriented approach in which the teacher identifies the used learning technologies and

Effect of blending temperature on the mechanical properties of PVC/ENR blend upon irradiation

International Nuclear Information System (INIS)

Chantara Thevy Ratnam; Khairul Zaman Mohd Dahlan; Nasir, M.; Baharin, A.

2000-01-01

Poly (vinyl chloride) / epoxidized natural rubber blends were prepared with a Brabender plasticorder at 140, 150, 160, 170 and 180 degree C mixing temperatures. They were mixed at 50 rpm rotor speed for 10 min. The blends were irradiated with doses ranging from 0-200 kGy. Changes in tensile strength, modulus at 100% elongation, gel fraction and damping properties (tan δ) of the blends with increasing mixing temperatures and irradiation doses were investigated. In general, it was observed that the mixing temperature is important in maximizing the positive effect of irradiation. Results revealed that a readily miscible blend enjoy maximum benefit from irradiation meanwhile irradiation impart miscibility to a partially miscible PVC/ENR blend. The enhancement in blend properties is believed to be attributed by the irradiation-induced crosslinking along with irradiation-induced interaction between the polymers. The radiation-induced degradation found to be prominent at higher doses for blend that has undergone excessive thermal degradation. However evidence did not reveal the specific nature of radiation-induced reaction responsible for the improved interactions of the blends. (author)

Blending Words Found In Social Media

Directory of Open Access Journals (Sweden)

Giyatmi Giyatmi

2017-12-01

Full Text Available There are many new words from the social media such as Netizen, Trentop, and Delcon. Those words include in blending. Blending is one of word formations combining two clipped words to form a brand new word. The researchers are interested in analyzing blend words used in the social media such as Instagram, Twitter, Facebook, and Blackberry Messenger. This research aims at (1 finding blend words used in the social media (2 describing kinds of blend words used in social media (3 describing the process of blend word formation used in the social media. This research uses some theories dealing with definition of blending and kinds of blending. This research belongs to descriptive qualitative research. Data of the research are English blend words used in social media. Data sources of this research are websites consisting of some English words used in social media and some social media users as the informant. Techniques of data collecting in this research are observation and simak catat. Observation is by observing some websites consisting of some English words used in social media. Simak catat is done by taking some notes on the data and encoding in symbols such as No/Blend words/Kinds of Blending. The researchers use source triangulation to check the data from the researchers with the informant and theory triangulation to determine kinds of blending and blend word formation in social media. There are115 data of blend words. Those data consists of 65 data of Instagram, 47 data of Twitter, 1 datum of Facebook, and 2 data of Blackberry Messenger. There are 2 types of blending used in social media;108 data of blending with clipping and 7 data of blending with overlapping. There are 10 ways of blend word formation found in this research.

Design Principles for the Blend in Blended Learning: A Collective Case Study

Science.gov (United States)

Lai, Ming; Lam, Kwok Man; Lim, Cher Ping

2016-01-01

This paper reports on a collective case study of three blended courses taught by different instructors in a higher education institution, with the purpose of identifying the different types of blend and how the blend supports student learning. Based on the instructors' and students' interviews, and document analysis of course outlines, two major…

Calculation procedure for formulating lauric and palmitic fat blends based on the grouping of triacylglycerol melting points

Directory of Open Access Journals (Sweden)

B. P. Nusantoro

2018-01-01

Full Text Available A calculation procedure for formulating lauric and palmitic fat blends has been developed based on grouping TAG melting points. This procedure offered more flexibility in choosing the initial fats and oils and eventually gave deeper insight into the existing chemical compositions and better prediction on the physicochemical properties and microstructure of the fat blends. The amount of high, medium and low melting TAGs could be adjusted using the given calculation procedure to obtain the desired functional properties in the fat blends. Solid fat contents and melting behavior of formulated fat blends showed particular patterns with respect to ratio adjustments of the melting TAG groups. These outcomes also suggested that both TAG species and their quantity had a significant influence on the crystallization behavior of the fat blends. Palmitic fat blends, in general, were found to exhibit higher SFC values than those of Lauric fat blends. Instead of the similarity in crystal microstructure, lauric fat blends were stabilized at β polymorph while palmitic fat blends were stabilized at β’ polymorph.

Calculation procedure for formulating lauric and palmitic fat blends based on the grouping of triacylglycerol melting points

International Nuclear Information System (INIS)

Nusantoro, B.P.; Yanty, N.A.M.; Van de Walle, D.; Hidayat, C.; Danthine, S.; Dewettinck, K.

2017-01-01

A calculation procedure for formulating lauric and palmitic fat blends has been developed based on grouping TAG melting points. This procedure offered more flexibility in choosing the initial fats and oils and eventually gave deeper insight into the existing chemical compositions and better prediction on the physicochemical properties and microstructure of the fat blends. The amount of high, medium and low melting TAGs could be adjusted using the given calculation procedure to obtain the desired functional properties in the fat blends. Solid fat contents and melting behavior of formulated fat blends showed particular patterns with respect to ratio adjustments of the melting TAG groups. These outcomes also suggested that both TAG species and their quantity had a significant influence on the crystallization behavior of the fat blends. Palmitic fat blends, in general, were found to exhibit higher SFC values than those of Lauric fat blends. Instead of the similarity in crystal microstructure, lauric fat blends were stabilized at β polymorph while palmitic fat blends were stabilized at β’ polymorph. [es

Blended acquisition with dispersed source arrays

NARCIS (Netherlands)

Berkhout, A.J.

2012-01-01

Blended source arrays are historically configured with equal source units, such as broadband vibrators (land) and broadband air-gun arrays (marine). I refer to this concept as homogeneous blending. I have proposed to extend the blending concept to inhomogeneous blending, meaning that a blended

Performance and Emission Analysis of a Diesel Engine Using Linseed Biodiesel Blends

Directory of Open Access Journals (Sweden)

M. M. Tunio

2018-06-01

Full Text Available The core object of this study is to examine the suitability of linseeds for biodiesel production. The performance of an engine at different proportions of linseed blends with petro-diesel and the amount of emissions rate were investigated. Initially, linseed biodiesel was produced through transesterification process, and then it was mixed with petro-diesel fuel (D100 blends at volumetric ratios of 10% (LB10, 20% (LB20, and 30% (LB30. The properties of linseed biodiesel and its blends were investigated and compared with petro-diesel properties with reference to ASTM standards. It has been observed that the fuel properties of produced biodiesel are within ASTM permissible limits. The specific fuel consumption (SFC of LB10 blend has been found lesser compared to LB20 and LB30. SFC of D100 is slightly less than that of all the blends. The brake thermal efficiency (BTE of LB30 is greater than that of pure diesel D100 at maximum load and greater than that of LB10 and LB20. The heat dissipation rate in all linseed blends is found to have been less than that of D100. Carbon monoxide, carbon dioxide and NOx emissions of linseed blends are mostly lower in comparison with D100’s. Among all blends, LB10 was found more suitable alternative fuel for diesel engines and can be blended with petro diesel without engine modifications. It can be concluded that cultivation and production of linseed in Pakistan is very promising, therefore, it is recommended that proper exploitation and use of linseed for energy production may be encouraged through pertinent agencies of Pakistan.

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…

Apparatus for blending small particles

International Nuclear Information System (INIS)

Bradley, R.A.; Reese, C.R.; Sease, J.D.

1975-01-01

An apparatus is described for blending small particles and uniformly loading the blended particles in a receptacle. Measured volumes of various particles are simultaneously fed into a funnel to accomplish radial blending and then directed onto the apex of a conical splitter which collects the blended particles in a multiplicity of equal subvolumes. Thereafter the apparatus sequentially discharges the subvolumes for loading in a receptacle. A system for blending nuclear fuel particles and loading them into fuel rod molds is described in a preferred embodiment

78 FR 75238 - Federal Housing Administration (FHA) Risk Management Initiatives: New Manual Underwriting...

Science.gov (United States)

2013-12-11

...-AJ07 Federal Housing Administration (FHA) Risk Management Initiatives: New Manual Underwriting... case numbers assigned on or after a date to be established by Mortgagee Letter following publication of... constrained. FHA played this role in the recent housing crisis, and the volume of FHA insurance increased...

Health care administrators' perspectives on the role of absorptive capacity for strategic change initiatives: a qualitative study.

Science.gov (United States)

Kash, Bita A; Spaulding, Aaron; Gamm, Larry; Johnson, Christopher E

2013-01-01

The dimensions of absorptive capacity (ACAP) are defined, and the importance of ACAP is established in the management literature, but the concept has not been applied to health care organizations attempting to implement multiple strategic initiatives. The aim of this study was to test the utility of ACAP by analyzing health care administrators' experiences with multiple strategic initiatives within two health systems. Results are drawn from administrators' assessments of multiple initiatives within two health systems using in-depth personal interviews with a total of 61 health care administrators. Data analysis was performed following deductive qualitative analysis guidelines. Interview transcripts were coded based on the four dimensions of ACAP: acquiring, assimilating, internalizing/transforming, and exploiting knowledge. Furthermore, we link results related to utilization of management resources, including number of key personnel involved and time consumption, to dimensions of ACAP. Participants' description of multiple strategic change initiatives confirmed the importance of the four ACAP dimensions. ACAP can be a useful framework to assess organizational capacity with respect to the organization's ability to concurrently implement multiple strategic initiatives. This capacity specifically revolves around human capital requirements from upper management based on the initiatives' location or stage within the ACAP framework. Strategic change initiatives in health care can be usefully viewed from an ACAP perspective. There is a tendency for those strategic initiatives ranking higher in priority and time consumption to reflect more advanced dimensions of ACAP (assimilate and transform), whereas few initiatives were identified in the ACAP "exploit" dimension. This may suggest that health care leaders tend to no longer identify as strategic initiatives those innovations that have moved to the exploitation stage or that less attention is given to the exploitation

Looking Back and Looking Forward: A Glimpse of Blended Learning in Higher Education from 2007-2017

Science.gov (United States)

Taylor, Maurice; Vaughan, Norman; Ghani, Shehzad K.; Atas, Sait; Fairbrother, Michael

2018-01-01

Using an engagement in research approach this article explores the landscape of blended learning in higher education over the last decade by comparing the results of a critical literature review by Vaughan to an instrumental case study that identified key factors that led to the implementation of a blended learning initiative in one medium sized…

Investigation of diesel-ethanol blended fuel properties with palm methyl ester as co-solvent and blends enhancer

Directory of Open Access Journals (Sweden)

Mat Taib Norhidayah

2017-01-01

Full Text Available Diesel engine is known as the most efficient engine with high efficiency and power but always reported as high fuel emission. Malaysia National Automotive Policy (NAP was targeting to improve competitive regional focusing on green technology development in reducing the emission of the engine. Therefore, ethanol was introduced to reduce the emission of the engine and while increasing its performance, Palm methyl ester was introduced as blend enhancer to improve engine performance and improve diesel-ethanol blends stability. This paper aimed to study the characteristics of the blends and to prove the ability of palm-methyl-ester as co-solvent in ethanol-diesel blends. Stability and thermophysical test were carried out for different fuel compositions. The stability of diesel-ethanol blended was proved to be improved with the addition of PME at the longer period and the stability of the blends changed depending on temperature and ethanol content. Density and viscosity of diesel-ethanol-PME blends also give higher result than diesel-ethanol blends and it's proved that PME is able to increase density and viscosity of blends. Besides, heating value of the blends also increases with the increasing PME in diesel-ethanol blends.

Tapioca starch blended alginate mucoadhesive-floating beads for intragastric delivery of Metoprolol Tartrate.

Science.gov (United States)

Biswas, Nikhil; Sahoo, Ranjan Kumar

2016-02-01

The objective of the study was to develop tapioca starch blended alginate mucoadhesive-floating beads for the intragastric delivery of Metoprolol Tartrate (MT). The beads were prepared by ionotropic gelation method using calcium chloride as crosslinker and gas forming calcium carbonate (CaCO3) as floating inducer. The alginate gel beads having 51-58% entrapped MT showed 90% release within 45 min in gastric medium (pH 1.2). Tapioca starch blending markedly improved the entrapment efficiency (88%) and sustained the release for 3-4 h. A 12% w/w HPMC coating on these beads extended the release upto 9-11 h. In vitro wash off and buoyancy test in gastric media revealed that the beads containing CaCO3 has gastric residence of more than 12 h. In vitro optimized multi-unit formulation consisting of immediate and sustained release mucoadhesive-floating beads (40:60) showed good initial release of 42% MT within 1h followed by a sustained release of over 90% for 11 h. Pharmacokinetic study performed in rabbit model showed that the relative oral bioavailability of MT after administration of oral solution, sustain release and optimized formulation was 51%, 67% and 87%, respectively. Optimized formulation showed a higher percent inhibition of isoprenaline induced heart rate in rabbits for almost 12 h. Copyright © 2015 Elsevier B.V. All rights reserved.

On the solution of petrochemical blending problems with classical ...

African Journals Online (AJOL)

In this paper a comparison of classical metaheuristic techniques over dierent sizes of petro- chemical blending problems is presented. Three problems are taken from the literature and used for initial comparisons and parameter setting. A fourth instance of real world size is then introduced and the best performing algorithm ...

Radiation effect on PVC/ENR blends

International Nuclear Information System (INIS)

Chantara Thevy Ratnam; Khairul Zaman Mohd Dahlan

1997-01-01

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

Deproteinised natural rubber latex grafted poly(dimethylaminoethyl methacrylate) - poly(vinyl alcohol) blend membranes: Synthesis, properties and application.

Science.gov (United States)

Jayadevan, Janisha; Alex, Rosamma; Gopalakrishnapanicker, Unnikrishnan

2018-02-01

Natural rubber latex was initially deproteinised (DNRL) and then subjected to physicochemical modifications to make high functional membranes for drug delivery applications. Initially, DNRL was prepared by incubating with urea, sodiumdodecylsulphate and acetone followed by centrifugation. The deproteinisation was confirmed by CHN analysis. The DNRL was then chemically modified by grafting (dimethylaminoethyl methacrylate) onto NR particles by using a redox initiator system viz; cumene hydroperoxide/tetraethylenepentamine, followed by dialysis for purification. The grafting was confirmed by dynamic light scattering, Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The grafted system was blended with a hydrophilic adhesive polymer PVA and casted into membranes. The membranes after blending showed enhanced mechanical properties with a threshold concentration of PVA. The moisture uptake, swelling and water contact angle experiments indicated an increased hydrophilicity with an increased PVA content in the blend membranes. The grafted DNRL possessed significant antibacterial property which has been found to be retained in the blended form. A notable decrease in cytotoxicity was observed for the modified DNRL membranes than the bare DNRL membranes. The in-vitro drug release studies using rhodamine B as a model drug, confirmed the utility of the prepared membranes to function as a drug delivery matrix. Copyright © 2017 Elsevier B.V. All rights reserved.

Blending into the mix

Energy Technology Data Exchange (ETDEWEB)

Adams, R.G.; Gibb, W.H.; Majid, K.A. [Power Technology (United Kingdom)

1999-07-01

Successful coal blending requires finding a careful balance between fuel costs and plant performance. A recent study of a Malaysian power plant shows how the utility (Tenaga Nasional Berhad (TNB)) could reduce fuel costs while avoiding boiler operating problems normally associated with firing low-grade coals. TNB`s Kaper 2220 MW power station in Selangor needed an improved method of coal blending for two new 500 MW units and for two existing 300 MW units. UK`s Power Technology was commissioned to identify what coal blends the boiler could tolerate. A Coal Quality Impact Model (CQIM) analysis of the effect of different coals and coal blends on combustion performance and economics, and a performance analysis of coal yard handling facility was made to determine whether the accuracy of the required blend could be achieved (using a Coal Handling Simulation, CHAS, software package). The CQIM study showed that the proportion of cheaper coals could be increased from 20% to 50% provided each shipment was adequately sampled. The CHAS study showed that use of a flat back reclaimer or modifications to the dry coal stove would allow accurate blending. 5 figs., 1 tab.

Serological changes induced by blend of sunset yellow, metanil yellow and tartrazine in swiss albino rat, rattus norvegicus.

Science.gov (United States)

Saxena, Beenam; Sharma, Shiv

2014-01-01

The present study was carried out to evaluate the toxic effect of blend of some food colors on Swiss albino rats. A blend (1:1:1) of sunset yellow, metanil yellow and tartrazine showed additive effects on serological parameters which indicate that addition of these dye together in food stuff may give rise to more toxic effects than are produced by each dye individually. Animals were divided into four groups (I, II, III, and IV). First group was treated as control and respective group of animals received 25, 50 and 75 mg/kg body weight blend of food colors by gavaging up to 30 days. The serological study showed a decrease in total protein and albumin and an increase in alkaline phosphatase, SGPT and total bilirubin. The results revealed that oral administration of these blend did not affect the body weight gain. The prolonged consumption of the blend may cause adverse effect on human health.

Decentralized Blended Acquisition

NARCIS (Netherlands)

Berkhout, A.J.

2013-01-01

The concept of blending and deblending is reviewed, making use of traditional and dispersed source arrays. The network concept of distributed blended acquisition is introduced. A million-trace robot system is proposed, illustrating that decentralization may bring about a revolution in the way we

Blended Learning: enabling Higher Education Reform

Directory of Open Access Journals (Sweden)

Kathleen Matheos

2018-01-01

Full Text Available Blended learning research and practice have been areas of growth for two decades in Canada, with over 95% of Canadian higher education institutions involved in some form of blended learning. Despite strong evidence based research and practice blended learning, for the most part, has remained at sidelined in Canadian universities. The article argues the need for blended learning to situate itself within the timely and crucial Higher Education Reform (HER agenda. By aligning the affordances of blended learning with the components of HER, blended learning can clearly serve as an enabler for HER.

A systematic review examining the effectiveness of blending technology with team-based learning.

Science.gov (United States)

River, Jo; Currie, Jane; Crawford, Tonia; Betihavas, Vasiliki; Randall, Sue

2016-10-01

Technological advancements are rapidly changing nursing education in higher education settings. Nursing academics are enthusiastically blending technology with active learning approaches such as Team Based Learning (TBL). While the educational outcomes of TBL are well documented, the value of blending technology with TBL (blended-TBL) remains unclear. This paper presents a systematic review examining the effectiveness of blended-TBL in higher education health disciplines. This paper aimed to identify how technology has been incorporated into TBL in higher education health disciplines. It also sought to evaluate the educational outcomes of blended-TBL in terms of student learning and preference. A review of TBL research in Medline, CINAHL, ERIC and Embase databases was undertaken including the search terms, team based learning, nursing, health science, medical, pharmaceutical, allied health education and allied health education. Papers were appraised using the Critical Appraisal Skills Program (CASP). The final review included 9 papers involving 2094 student participants. A variety of technologies were blended with TBL including interactive eLearning and social media. There is limited evidence that blended-TBL improved student learning outcomes or student preference. Enthusiasm to blend technology with TBL may not be as well founded as initially thought. However, few studies explicitly examined the value of incorporating technology into TBL. There is a clear need for research that can discern the impact of technology into TBL on student preference and learning outcomes, with a particular focus on barriers to student participation with online learning components. Copyright © 2016 Elsevier Ltd. All rights reserved.

A formative evaluation of a high school blended learning biology course

Science.gov (United States)

Nellman, Stephen William

As growing student populations continue to tax the resources of public high schools, administrators are constantly looking for ways to address the needs of all students. One option for increasing the number of students in a classroom without sacrificing quality of instruction is to use "blended learning". Blended learning is defined by Marsh et al. (2003, p.2) as a situation where "face-to-face and distance education delivery methods and resources are merged". In such a course, students receive the benefits of classroom-based instruction, while also benefiting from several aspects of distance learning. This is especially true for science courses that rely heavily on both hands-on labs and various multimedia. The purpose of this study was a formative evaluation of a high school blended learning biology course, focusing on a genetics unit. The research question addressed by the study was "Will participants increase their domain knowledge and problem-solving skills after instruction in a high school level blended distance learning biology course? Also investigated was if higher levels of self-regulation skills were correlated to higher levels of content-understanding and problem-solving. The study was composed of a pilot study and a main study. Participants were students in an urban Southern California public high school biology course. Classroom instruction was from a single instructor, and online content was managed using the "Moodle" course management system. Participants were assessed for their gains in genetics content-understanding, genetics problem-solving skills (Punnett squares), and self-regulation. Additionally, participant reactions to the blended instruction model were surveyed. Results indicated that significant increases (pself-regulation skills were not shown to be significantly correlated to increased content-understanding, or problem-solving skills. Participants reacted positively to the blended model, suggesting that it be used more often in their

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. ...

Effect of Blending on the Composition and Acceptability of Blends of ...

African Journals Online (AJOL)

However the blend was found deficient in lysine, leucine, iso-leucine and phenylalanine when compared with the FAO recommendations for infants. Increased levels of pigeon pea in the blend also resulted in significant increases in potassium, phosphorus, sodium, magnesium and calcium. Similarly, increased levels of ...

Formulation and In Vitro Release Kinetics of Mucoadhesive Blend Gels Containing Matrine for Buccal Administration.

Science.gov (United States)

Chen, Xiaojin; Yan, Jun; Yu, Shuying; Wang, Pingping

2018-01-01

Enterovirus 71 (EV71) is a pathogenic factor of severe hand, foot, and mouth disease (HFMD). No vaccine or specific treatment is currently available for EV71 infection. Hence, we developed a buccal mucoadhesive gel containing matrine to protect against HFMD. Mucoadhesive gels were prepared by Carbopol 974P and were combined with Carbopol 971P, sodium carboxymethyl cellulose (CMC-Na), or hydroxypropylmethy cellulose (HPMC K100M). The formulations were characterized in terms of tensile testing and continuous flow techniques for mucoadhesion. The rheological studies and in vitro drug release characteristics were also investigated. The results showed that combinations of two polymers significantly improved mucoadhesion, especially Carbopol 974P blended with HPMC. Carbopol 974P to HPMC blend ratios of 1:1 and 2:1 induced better mucoadhesion in the tensile test and continuous flow method, respectively. The most sustained release was obtained at a Carbopol 974P to HPMC ratio of 2.5:1. A predominantly non-Fickian diffusion release mechanism was obtained. The gel containing 2.5% Carbopol 974P combined with 1% HPMC showed good mucoadhesion properties and sustained drug release.

Blended Approach to Occupational Performance (BAOP: Guidelines Enabling Children with Autism

Directory of Open Access Journals (Sweden)

Jordan M. Skowronski

2017-01-01

Full Text Available The performance of daily activities is impacted by motor impairments in children with autism spectrum disorders (ASD. Research has recently demonstrated the prevalence and specificity of motor impairments in people with ASD. The motor learning of individuals with ASD is partially intact, and evidence suggests that a method to alter skill learning and repeated practice of motor sequences might be beneficial. Aiming to use this knowledge to guide occupational therapy interventions, initial guidelines for children with ASD blended Cognitive Orientation to daily Occupational Performance (CO-OP with virtual reality (VR were created. An expert panel reviewed the initial guidelines. The results from the semi-structured expert panel discussion were to (a increase the number of sessions, (b provide more visuals to children, and (c use VR as a reinforcer. Guidelines were revised accordingly. The revised guidelines, called Blended Approach to Occupational Performance (BAOP, are ready for further testing.

pH sensitivity of emeraldine salt polyaniline and poly(vinyl butyral) blend

International Nuclear Information System (INIS)

Nguyen, Hoa Duyen; Hoang, Ngoc Vu; Le, Nguyen Ngan; Nguyen, Thi Ngoc Nhien; Doan, Duc Chanh Tin; Dang, Mau Chien; Nguyen, Thi Ha

2014-01-01

pH sensitivity of emeraldine salt polyaniline (ES-PANI) and poly(vinyl butyral) (PVB) blend film was investigated. This blend film can be used as a pH sensing element in new-type pH sensors to replace traditional instruments based on fragile glass electrodes for pH measurement of water in aquaculture farming. Structural and optical characteristic of PANI were studied by Fourier transform infrared spectroscopy (FTIR) and ultraviolet visible spectroscopy (UV–vis). Electrical characterization of ES-PANI:PVB blend films versus pH was performed with chemiresistors fabricated by micro-lithography. A ES-PANI:PVB layer was drop-coated on comb-shaped platinum electrodes patterned on SiO 2 /Si substrates. Scanning electron microscope (SEM) and optical microscope were used to investigate morphology of the fabricated platinum electrodes and the coated polymer blend films. I–V measurements of the polymer-coated chemiresistors were performed at very low relative humidity after the polymer films were exposed to pH 1–8. The results showed that logarithm of electrical resistance of the ES-PANI:PVB films increased almost linearly as pH increased from 1 to 8. The initial results showed that the PANI blend-coated chemiresistors can be used as pH sensors for water quality monitoring. (paper)

Morphology stabilization of heterogeneous blends

International Nuclear Information System (INIS)

1980-01-01

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)

Locally restricted blending of Blobtrees

NARCIS (Netherlands)

Groot, de Erwin; Wyvill, B.; Wetering, van de H.M.M.

2009-01-01

Blobtrees are volume representations particularly useful for models which require smooth blending. When blending is applied to two or more Blobtree models, extra volume will be created in between the two surfaces to form a smooth connection. Although it is easy to apply blending, it is hard to

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.

Towards an intelligent learning management system under blended learning trends, profiles and modeling perspectives

CERN Document Server

Dias, Sofia B; Hadjileontiadis, Leontios J

2013-01-01

This book offers useful information that evokes initiatives towards rethinking of the value, efficiency, inclusiveness, effectiveness and personalization of the intelligent learning management systems-based blended-learning environment.

Fundamentals of the administrative decentralization process

Directory of Open Access Journals (Sweden)

Mihaela Lupăncescu

2017-12-01

Full Text Available Public administration, as an activity carried out by the administrative authorities, can be achieved through several forms of organization. In this sense, centralization, deconcentration and decentralization, together with its corollary, local autonomy, constitute in organizational regimes of an administrative nature, more or less democratic, and with characteristics that vary according to the degree of dependence between the authorities of the public administration institutions at the central level and local public administration authorities.There is no single form of organization that incorporates the characteristics of a particular regime. The complex expectations of modern society have led to the blending of features of different forms of organization in order to create a balance of activity within the public administration, in order to exercise the functions of executive power for the benefit of citizens, not by conferring unlimited autonomy but by considering the fundamental principle of legality.

Blended Learning over Two Decades

Science.gov (United States)

Zhonggen, Yu; Yuexiu, Zhejiang

2015-01-01

The 21st century has witnessed vast amounts of research into blended learning since the conception of online learning formed the possibility of blended learning in the early 1990s. The theme of this paper is blended learning in mainstream disciplinary communities. In particular, the paper reports on findings from the last two decades which looked…

Evaporation characteristics of ETBE-blended gasoline.

Science.gov (United States)

Okamoto, Katsuhiro; Hiramatsu, Muneyuki; Hino, Tomonori; Otake, Takuma; Okamoto, Takashi; Miyamoto, Hiroki; Honma, Masakatsu; Watanabe, Norimichi

2015-04-28

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 developed. Copyright © 2015 Elsevier B.V. All rights reserved.

Evaporation characteristics of ETBE-blended gasoline

International Nuclear Information System (INIS)

Okamoto, Katsuhiro; Hiramatsu, Muneyuki; Hino, Tomonori; Otake, Takuma; Okamoto, Takashi; Miyamoto, Hiroki; Honma, Masakatsu; Watanabe, Norimichi

2015-01-01

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

Evaporation characteristics of ETBE-blended gasoline

Energy Technology Data Exchange (ETDEWEB)

Okamoto, Katsuhiro, E-mail: okamoto@nrips.go.jp [National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, Chiba 277-0882 (Japan); Hiramatsu, Muneyuki [Yamanashi Prefectural Police H.Q., 312-4 Kubonakajima, Isawa-cho, Usui, Yamanashi 406-0036 (Japan); Hino, Tomonori; Otake, Takuma [Metropolitan Police Department, 2-1-1 Kasumigaseki, Chiyoda-ku, Tokyo 100-8929 (Japan); Okamoto, Takashi; Miyamoto, Hiroki; Honma, Masakatsu; Watanabe, Norimichi [National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, Chiba 277-0882 (Japan)

2015-04-28

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

The POL Model: Using a Social Constructivist Framework to Develop Blended and Online Learning

DEFF Research Database (Denmark)

Dalsgaard, Christian; Godsk, Mikkel

2007-01-01

The paper presents a model for developing blended and online learning based on a given curriculum and typical learning objectives for university courses. The model consists of a three-step-process in which the instructor formulates product-oriented tasks, develops and structures the learning...... materials and tools, outlines a schedule, and supports the students' learning activity in developing a product. The model is based on our experiences with transforming traditional lecture-based lessons into problem-based blended and online learning using a social constructivist approach and a standard...... virtual learning environment (VLE). Our initial experiments indicate that our model is useful to develop blended and online modules and, furthermore, it seems fruitful to use a social constructivist framework and orienting learning activities towards the development of products....

Entanglement in miscible blends

Science.gov (United States)

Watanabe, Hiroshi

2010-03-01

The entanglement length Le of polymer chains (corresponding to the entanglement molecular weight Me) is not an intrinsic material parameter but changes with the interaction with surrounding chains. For miscible blends of cis-polyisoprene (PI) and poly(tert-butyl styrene) (PtBS), changes of Le on blending was examined. It turned out that the Le averaged over the number fractions of the Kuhn segments of the components (PI and PtBS) satisfactorily describes the viscoelastic behavior of pseudo-monodisperse blends in which the terminal relaxation time is the same for PI and PtBS.

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...... polymer in the other. The observed solubility strongly depends on blend composition and blending method. The T-g measurements showed maximum mutual solubility around 50/50 composition. The miscibility of PC/PS blended after the third stage (melt injection molding) was higher than that after the first...... by measuring their glass transition temperatures (T-g) and their specific heat increment (DeltaC(p)). Differential scanning calorimetry (DSC) was used to examine nine blend compositions. Shifts in glass transition temperature (T-g) of the two phases in melt-mixed PC/PS blends suggest partial miscibility of one...

Effects of Blended-Cement Paste Chemical Composition Changes on Some Strength Gains of Blended-Mortars

Science.gov (United States)

Kirgiz, Mehmet Serkan

2014-01-01

Effects of chemical compositions changes of blended-cement pastes (BCPCCC) on some strength gains of blended cement mortars (BCMSG) were monitored in order to gain a better understanding for developments of hydration and strength of blended cements. Blended cements (BC) were prepared by blending of 5% gypsum and 6%, 20%, 21%, and 35% marble powder (MP) or 6%, 20%, 21%, and 35% brick powder (BP) for CEMI42.5N cement clinker and grinding these portions in ball mill at 30 (min). Pastes and mortars, containing the MP-BC and the BP-BC and the reference cement (RC) and tap water and standard mortar sand, were also mixed and they were cured within water until testing. Experiments included chemical compositions of pastes and compressive strengths (CS) and flexural strengths (FS) of mortars were determined at 7th-day, 28th-day, and 90th-day according to TS EN 196-2 and TS EN 196-1 present standards. Experimental results indicated that ups and downs of silica oxide (SiO2), sodium oxide (Na2O), and alkali at MP-BCPCC and continuously rising movement of silica oxide (SiO2) at BP-BCPCC positively influenced CS and FS of blended cement mortars (BCM) in comparison with reference mortars (RM) at whole cure days as MP up to 6% or BP up to 35% was blended for cement. PMID:24587737

Effects of Blended-Cement Paste Chemical Composition Changes on Some Strength Gains of Blended-Mortars

Directory of Open Access Journals (Sweden)

Mehmet Serkan Kirgiz

2014-01-01

Full Text Available Effects of chemical compositions changes of blended-cement pastes (BCPCCC on some strength gains of blended cement mortars (BCMSG were monitored in order to gain a better understanding for developments of hydration and strength of blended cements. Blended cements (BC were prepared by blending of 5% gypsum and 6%, 20%, 21%, and 35% marble powder (MP or 6%, 20%, 21%, and 35% brick powder (BP for CEMI42.5N cement clinker and grinding these portions in ball mill at 30 (min. Pastes and mortars, containing the MP-BC and the BP-BC and the reference cement (RC and tap water and standard mortar sand, were also mixed and they were cured within water until testing. Experiments included chemical compositions of pastes and compressive strengths (CS and flexural strengths (FS of mortars were determined at 7th-day, 28th-day, and 90th-day according to TS EN 196-2 and TS EN 196-1 present standards. Experimental results indicated that ups and downs of silica oxide (SiO2, sodium oxide (Na2O, and alkali at MP-BCPCC and continuously rising movement of silica oxide (SiO2 at BP-BCPCC positively influenced CS and FS of blended cement mortars (BCM in comparison with reference mortars (RM at whole cure days as MP up to 6% or BP up to 35% was blended for cement.

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...... learning solutions do not often live up to the potential of the approach or fail to produce the intended results because the students are not always equipped to handle the technical, psychological and organisational challenges of blended learning approaches. This project surveyed seventy-five first year...... the students’ e-readiness for an implementation of a blend-ed course design....

Peel/seal properties of poly(ethylene methyl acrylate)/polybutene-1 blend films

Science.gov (United States)

Mohammdi, Seyedeh Raziyeh; Ajji, Abdellah; Tabatabaei, Seyed H.

2015-05-01

Nowadays, the possibility to easy open a food package is of great interest both from the consumer and food producers' perspective. In this study, the peel/seal properties of poly (ethylene methyl acrylate) (EMA)/polybutene-1 (PB-1) blend films were investigated. Three blends of EMA/PB-1 with different methyl acrylate (MA) content were prepared using cast extrusion process. Differential Scanning Calorimetry (DSC) was used to investigate the thermal behavior as well as the crystalinity of the blends. The effect of polymer matrix on the crystalline structure of PB-1 was studied using Wide Angle X-ray Diffraction (WAXD) and DSC. T-peel tests were carried out on the heat sealed films at various seal temperatures. The effect of MA content and heat seal temperature on peel/seal properties (i.e. peel initiation temperature, temperature window of sealability and peel strength) of the films were studied.

Peel/seal properties of poly(ethylene methyl acrylate)/polybutene-1 blend films

Energy Technology Data Exchange (ETDEWEB)

Mohammdi, Seyedeh Raziyeh; Ajji, Abdellah; Tabatabaei, Seyed H. [Department of Chemical Engineering, École Polytechnique de Montréal, Montréal, Québec, H3C3A7 (Canada)

2015-05-22

Nowadays, the possibility to easy open a food package is of great interest both from the consumer and food producers’ perspective. In this study, the peel/seal properties of poly (ethylene methyl acrylate) (EMA)/polybutene-1 (PB-1) blend films were investigated. Three blends of EMA/PB-1 with different methyl acrylate (MA) content were prepared using cast extrusion process. Differential Scanning Calorimetry (DSC) was used to investigate the thermal behavior as well as the crystalinity of the blends. The effect of polymer matrix on the crystalline structure of PB-1 was studied using Wide Angle X-ray Diffraction (WAXD) and DSC. T-peel tests were carried out on the heat sealed films at various seal temperatures. The effect of MA content and heat seal temperature on peel/seal properties (i.e. peel initiation temperature, temperature window of sealability and peel strength) of the films were studied.

Peel/seal properties of poly(ethylene methyl acrylate)/polybutene-1 blend films

International Nuclear Information System (INIS)

Mohammdi, Seyedeh Raziyeh; Ajji, Abdellah; Tabatabaei, Seyed H.

2015-01-01

Nowadays, the possibility to easy open a food package is of great interest both from the consumer and food producers’ perspective. In this study, the peel/seal properties of poly (ethylene methyl acrylate) (EMA)/polybutene-1 (PB-1) blend films were investigated. Three blends of EMA/PB-1 with different methyl acrylate (MA) content were prepared using cast extrusion process. Differential Scanning Calorimetry (DSC) was used to investigate the thermal behavior as well as the crystalinity of the blends. The effect of polymer matrix on the crystalline structure of PB-1 was studied using Wide Angle X-ray Diffraction (WAXD) and DSC. T-peel tests were carried out on the heat sealed films at various seal temperatures. The effect of MA content and heat seal temperature on peel/seal properties (i.e. peel initiation temperature, temperature window of sealability and peel strength) of the films were studied

Mechanical, Thermal and Surface Investigations of Chitosan/Agar/PVA Ternary Blended Films

Directory of Open Access Journals (Sweden)

Esam A. El-Hefian

2011-01-01

Full Text Available The mechanical and thermal properties of chitosan/agar/poly vinyl alcohol (CS/AG/PVA ternary blended films having various proportions considering chitosan as the main component were investigated. The various variables static water contact angle such as contact angle, drop base area, drop volume and drop height was also studied in correlation with the variation of time. Results obtained from mechanical measurements showed a noticeable increase in the tensile strength (TS coincided with a sharp decrease in elongation percent at break (E% of blended films with increasing agar and PVA contents. The DSC results prevailed the development of an interaction between chitosan individual components: agar and PVA. Moreover, an enhancement of the wettability of the blends was obtained with increasing agar and PVA contents. It was also found that the pure CS film and the blended films with 90/05/05 and 80/10/10 compositions were more affected by time than blended films with other compositions when the contact angle, the drop height and the drop length were studied as a function of time. In addition, when the drop is initially placed on the substrate, the drop area and the drop volume of all films remained almost constant up to a certain time after which they showed a slight difference with the elapse of time.

Coalescence in PLA-PBAT blends under shear flow: Effects of blend preparation and PLA molecular weight

Energy Technology Data Exchange (ETDEWEB)

Nofar, M. [Center for High Performance Polymer and Composite Systems (CREPEC), Chemical Engineering Department, Polytechnique Montreal, Montreal, Quebec H3T 1J4, Canada and CREPEC, Department of Chemical Engineering, McGill University, Montreal, Quebec H3A 2B2 (Canada); Heuzey, M. C.; Carreau, P. J., E-mail: pierre.carreau@polymtl.ca [Center for High Performance Polymer and Composite Systems (CREPEC), Chemical Engineering Department, Polytechnique Montreal, Montreal, Quebec H3T 1J4 (Canada); Kamal, M. R. [CREPEC, Department of Chemical Engineering, McGill University, Montreal, Quebec H3A 2B2 (Canada); Randall, J. [NatureWorks LLC, 15305 Minnetonka Boulevard, Minnetonka, Minnesota 55345 (United States)

2016-07-15

Blends containing 75 wt. % of an amorphous polylactide (PLA) with two different molecular weights and 25 wt. % of a poly[(butylene adipate)-co-terephthalate] (PBAT) were prepared using either a Brabender batch mixer or a twin-screw extruder. These compounds were selected because blending PLA with PBAT can overcome various drawbacks of PLA such as its brittleness and processability limitations. In this study, we investigated the effects of varying the molecular weight of the PLA matrix and of two different mixing processes on the blend morphology and, further, on droplet coalescence during shearing. The rheological properties of these blends were investigated and the interfacial properties were analyzed using the Palierne emulsion model. Droplet coalescence was investigated by applying shear flows of 0.05 and 0.20 s{sup −1} at a fixed strain of 60. Subsequently, small amplitude oscillatory shear tests were conducted to investigate changes in the viscoelastic properties. The morphology of the blends was also examined using scanning electron microscope (SEM) micrographs. It was observed that the PBAT droplets were much smaller when twin-screw extrusion was used for the blend preparation. Shearing at 0.05 s{sup −1} induced significant droplet coalescence in all blends, but coalescence and changes in the viscoelastic properties were much more pronounced for the PLA-PBAT blend based on a lower molecular weight PLA. The viscoelastic responses were also somehow affected by the thermal degradation of the PLA matrix during the experiments.

Coalescence in PLA-PBAT blends under shear flow: Effects of blend preparation and PLA molecular weight

International Nuclear Information System (INIS)

Nofar, M.; Heuzey, M. C.; Carreau, P. J.; Kamal, M. R.; Randall, J.

2016-01-01

Blends containing 75 wt. % of an amorphous polylactide (PLA) with two different molecular weights and 25 wt. % of a poly[(butylene adipate)-co-terephthalate] (PBAT) were prepared using either a Brabender batch mixer or a twin-screw extruder. These compounds were selected because blending PLA with PBAT can overcome various drawbacks of PLA such as its brittleness and processability limitations. In this study, we investigated the effects of varying the molecular weight of the PLA matrix and of two different mixing processes on the blend morphology and, further, on droplet coalescence during shearing. The rheological properties of these blends were investigated and the interfacial properties were analyzed using the Palierne emulsion model. Droplet coalescence was investigated by applying shear flows of 0.05 and 0.20 s"−"1 at a fixed strain of 60. Subsequently, small amplitude oscillatory shear tests were conducted to investigate changes in the viscoelastic properties. The morphology of the blends was also examined using scanning electron microscope (SEM) micrographs. It was observed that the PBAT droplets were much smaller when twin-screw extrusion was used for the blend preparation. Shearing at 0.05 s"−"1 induced significant droplet coalescence in all blends, but coalescence and changes in the viscoelastic properties were much more pronounced for the PLA-PBAT blend based on a lower molecular weight PLA. The viscoelastic responses were also somehow affected by the thermal degradation of the PLA matrix during the experiments.

Blended Learning Design

DEFF Research Database (Denmark)

Pedersen, Lise

2015-01-01

University College Lillebaelt has decided that 30 percent of all educational elements must be generated as blended learning by the end of the year 2015 as part of a modernization addressing following educational needs: 1. Blended learning can help match the expectations of the future students who...... learning. 4. Blended learning can contribute to supporting and improving efficiency of educational efforts. This can for instance be done through programmes for several classes by using video conferencing, allocating traditional face to face teaching to synchronous and asynchronous study activities produce...... 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...

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,…

Thin films of polymer blends deposited by matrix-assisted pulsed laser evaporation: Effects of blending ratios

International Nuclear Information System (INIS)

Paun, Irina Alexandra; Ion, Valentin; Moldovan, Antoniu; Dinescu, Maria

2011-01-01

In this work, we show successful use of matrix-assisted pulsed laser evaporation (MAPLE) for obtaining thin films of PEG:PLGA blends, in the view of their use for controlled drug delivery. In particular, we investigate the influence of the blending ratios on the characteristics of the films. We show that the roughness of the polymeric films is affected by the ratio of each polymer within the blend. In addition, we perform Fourier transformed infrared spectroscopy (FTIR) measurements and we find that the intensities ratios of the infrared absorption bands of the two polymers are consistent with the blending ratios. Finally, we assess the optical constants of the polymeric films by spectroscopic ellipsometry (SE). We point out that the blending ratios exert an influence on the optical characteristics of the films and we validate the SE results by atomic force microscopy and UV-vis spectrophotometry. In all, we stress that the ratios in which the two polymers are blended have significant impact on the morphology, chemical structure and optical characteristics of the polymeric films deposited by MAPLE.

An Investigation into the Physico-chemical Properties of Transformer Oil Blends with Antioxidants extracted from Turmeric Powder

Science.gov (United States)

Dukhi, Veresha; Bissessur, Ajay; Ngila, Catherine Jane; Ijumba, Nelson Mutatina

2013-07-01

The blending of transformer oil (used mainly as an insulating oil) with appropriate synthetic antioxidants, such as BHT (2,6-di-tert-butyl-4-methylphenol) and DBP (2,6-di-tert-butylphenol) have been previously reported. This article is focused on the use of antioxidant extracts from turmeric (Curcuma longa), a natural source. Turmeric is well known for its antimicrobial, antioxidant and anticarcinogenic properties owing to the active nature of its components. Extracts from powdered turmeric were subsequently blended into naphthenic-based uninhibited virgin transformer oil, hereinafter referred to as extract-oil blends (E-OB). Thin-layer chromatography (TLC) of the oil blends revealed that five components extracted from turmeric powder were successfully blended into the oil. Subsequent gas chromatography-mass spectrometry (GC-MS) analysis confirmed the presence of the compounds: curcumene, sesquiphellandrene, ar-turmerone, turmerone and curlone. Thermogravimetric analysis (TGA) of the extract-oil blends, containing various levels of extracts, revealed an average temperature shift of ˜8.21°C in the initial onset of degradation in comparison to virgin non-blended oil. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay showed that an increase in the mass aliquot of turmeric extracts in the transformer oil increased the free radical scavenging activity of the oil. Electrical properties of the oil investigated showed that the dissipation factor in the blended oil was found to be lower than that of virgin transformer oil. Evidently, a lower dissipation value renders the oil blend as a superior insulator over normal virgin non-blended oil. This investigation elucidated improved physico-chemical properties of transformer oil blended with turmeric antioxidant extracts.

Emissions characteristics of higher alcohol/gasoline blends

International Nuclear Information System (INIS)

Gautam, M.; Martin, D.W.; Carder, D.

2000-01-01

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, CO 2 and organic matter hydrocarbon equivalent (OMHCE) from the higher alcohol/gasoline blends were very similar to those from neat gasoline. Cycle emissions of NO x 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)

Tensile and morphology properties of PLA/LNR blends modified with maleic anhydride grafted-polylactic acid and -natural rubber

Science.gov (United States)

Ruf, Mohd Farid Hakim Mohd; Ahmad, Sahrim; Chen, Ruey Shan; Shahdan, Dalila; Zailan, Farrah Diyana

2018-04-01

This research was carried out to investigate the addition of grafted copolymers of maleic anhydride grafted-polylactic acid(PLA-g-MA) and maleic anhydride grafted-natural rubber (NR-g-MA) on the tensile and morphology properties of polylactic acid/ liquid natural rubber (PLA/LNR) blends. Prior to blend preparation, the PLA-g-MA and NR-g-MA was first self-synthesized using maleic anhydride (MA) and dicumyl peroxide (DCP) as initiator together with the PLA and NR respectively. The PLA/LNR, PLA/LNR/PLA-g-MA and PLA/LNR/NR-g-MA blends were prepared via melt-blending method. The loading of PLA-g-MA and NR-g-MA was varied by 5, 10 and 15 wt% respectively. The addition of PLA-g-MA led to increment in tensile strength with 5 and 10 wt% while NR-g-MA gives lower than controlled sample (PLA/LNR blend). Scanning electron microscope (SEM) showed the interaction of the components in the blends. The PLA/LNR compatibilized with PLA-g-MA and NR-g-MA shows greater dispersion and adhesion.

Review Of Rheology Models For Hanford Waste Blending

International Nuclear Information System (INIS)

Koopman, D. C.; Stone, M.

2013-01-01

The area of rheological property prediction was identified as a technology need in the Hanford Tank Waste - waste feed acceptance initiative area during a series of technical meetings among the national laboratories, Department of Energy-Office of River Protection, and Hanford site contractors. Meacham et al. delivered a technical report in June 2012, RPP-RPT-51652 ''One System Evaluation of Waste Transferred to the Waste Treatment Plant'' that included estimating of single shell tank waste Bingham plastic rheological model constants along with a discussion of the issues inherent in predicting the rheological properties of blended wastes. This report was selected as the basis for moving forward during the technical meetings. The report does not provide an equation for predicting rheological properties of blended waste slurries. The attached technical report gives an independent review of the provided Hanford rheological data, Hanford rheological models for single tank wastes, and Hanford rheology after blending provided in the Meacham report. The attached report also compares Hanford to SRS waste rheology and discusses some SRS rheological model equations for single tank wastes, as well as discussing SRS experience with the blending of waste sludges with aqueous material, other waste sludges, and frit slurries. Some observations of note: Savannah River Site (SRS) waste samples from slurried tanks typically have yield stress >1 Pa at 10 wt.% undissolved solids (UDS), while core samples largely have little or no yield stress at 10 wt.% UDS. This could be due to how the waste has been processed, stored, retrieved, and sampled or simply in the differences in the speciation of the wastes. The equations described in Meacham's report are not recommended for extrapolation to wt.% UDS beyond the available data for several reasons; weak technical basis, insufficient data, and large data scatter. When limited data are available, for example two to three points, the equations

40 CFR 80.82 - Butane blending.

Science.gov (United States)

2010-07-01

... FUELS AND FUEL ADDITIVES Reformulated Gasoline § 80.82 Butane blending. A refiner for any refinery that produces gasoline by blending butane with conventional gasoline or reformulated gasoline or RBOB may meet... paragraph (b)(1) of this section, the refiner may: (i) Blend the butane with conventional gasoline, or...

Development of high-performance blended cements

Science.gov (United States)

Wu, Zichao

2000-10-01

This thesis presents the development of high-performance blended cements from industrial by-products. To overcome the low-early strength of blended cements, several chemicals were studied as the activators for cement hydration. Sodium sulfate was discovered as the best activator. The blending proportions were optimized by Taguchi experimental design. The optimized blended cements containing up to 80% fly ash performed better than Type I cement in strength development and durability. Maintaining a constant cement content, concrete produced from the optimized blended cements had equal or higher strength and higher durability than that produced from Type I cement alone. The key for the activation mechanism was the reaction between added SO4 2- and Ca2+ dissolved from cement hydration products.

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.

Structural characterization of HDPE/LLDPE blend-based nano composites obtained by different blending sequence

International Nuclear Information System (INIS)

Passador, Fabio R.; Ruvolo Filho, Adhemar; Pessan, Luiz A.

2011-01-01

The blending sequence affects the morphology formation of the nanocomposites. In this work, the blending sequences were explored to determine its influence in the rheological behavior of HDPE/LLDPE/OMMT nanocomposites. The nanocomposites were obtained by melt-intercalation using a mixture of LLDPE-g-MA and HDPE-g-MA as compatibilizer system in a torque rheometer at 180 deg C and five blending sequences were studied. The materials structures were characterized by wide angle X-ray diffraction (WAXD) and by rheological properties. The nanoclay's addition increased the shear viscosity at low shear rates, changing the behavior of HDPE/LLDPE matrix to a Bingham model behavior with an apparent yield stress. Intense interactions were obtained for the blending sequence where LLDPE and/or LLDPE-g-MA were first reinforced with organoclay since the intercalation process occurs preferentially in the amorphous phase. (author)

Mapping Cultural Frame Shifting in Interaction Design with Blending Theory

DEFF Research Database (Denmark)

Markussen, Thomas; Krogh, Peter Gall

2008-01-01

In this paper, we introduce Gilles Fauconnier & Mark Turner's blending theory as a new conceptual framework for explaining ‘cultural frame shifting' in interaction design. Cultural frame shifting is when people, through their explorative use of technology, are required imaginatively to reorganize...... their cultural background knowledge and expectations. In current HCI research it has occasionally been pointed out that a proper understanding of this phenomenon hinges on addressing the relationship between embodied interaction and cultural meaning construction as part of a larger interactive system. However...... 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 provide a tool...

Correlation between free-volume parameters and physical properties of polyethylene-nitrile rubber blend

Science.gov (United States)

Gomaa, E.; Mostafa, N.; Mohsen, M.; Mohammed, M.

2004-10-01

Positron annihilation lifetime spectroscopy (PALS) was used to study the immiscibility of a polar nitrile rubber (NBR) that had been blended with pure and waste, low- and high-density polyethylene (PE). The effect of the weight percent of the rubber added to the PE was also investigated. It was found that a complicated variation (positive and negative) in both free-volume parameters (τ3 and I 3) from the values of the initial polymers forms an immiscible blend. These results are supported by a significant broadening in the free-volume hole size distributions. This has been interpreted in terms of interfacial spaces created between the boundaries of the two phases. Furthermore, a correlation was established between the free-volume parameters (τ3 and I 3) and the electrical and mechanical properties of the before mentioned polymer blends as a function of the weight percent of waste PE.

Development and initial evaluation of blended cognitive behavioural treatment for major depression in routine specialized mental health care

DEFF Research Database (Denmark)

Kooistra, L. C.; Ruwaard, J.; Wiersma, J. E.

2016-01-01

the costs of mental health care, by reducing treatment duration and/or therapist contact. However, knowledge on blended care for depression is still limited. Objectives: To develop a blended cognitive behavioural treatment (bCBT) for depressed patients in an outpatient specialized mental health care centre...... with depressed patients (n = 9) in specialized mental health care. Patients' clinical profiles were established based on pre-treatment diagnostic information and patient self-reports on clinical measures. Patient treatment adherence rates were explored, together with patient ratings of credibility and expectancy...... the potential to be a valuable treatment option for patients with severe depression in specialized mental health care settings. Further exploration of the effectiveness of our bCBT protocol by means of a randomized controlled trial is warranted. © 2016 The Authors....

PLA-PMMA blends: A study by XPS and ToF-SIMS

International Nuclear Information System (INIS)

Cossement, D.; Gouttebaron, R.; Cornet, V.; Viville, P.; Hecq, M.; Lazzaroni, R.

2006-01-01

This paper reports which are the possibilities of quantification by time of flight secondary ion mass spectrometry (ToF-SIMS) for some polymer blends. In order to assess the composition of the mixtures, we studied first different poly(L-lactide)/polymethylmethacrylate (PLA/PMMA) blends by X-ray photoelectron spectroscopy (XPS), this technique being quantitative. By XPS fitting of the C 1s level, we found a very good agreement of the measured concentrations with the initial compositions. Concerning ToF-SIMS data treatment, we used principal component analysis (PCA) on negative spectra allowing to discriminate one polymer from the other one. By partial least square regression (PLS), we found also a good agreement between the ToF-SIMS predicted and initial compositions. This shows that ToF-SIMS, in a similar way to XPS, can lead to quantitative results. In addition, the observed agreement between XPS (60-100 A depth analyzed) and ToF-SIMS (10 A depth analyzed) measurements show that there is no segregation of one of the two polymers onto the surface

Blended 6-Hourly Sea Surface Wind Vectors and Wind Stress on a Global 0.25 Degree Grid (1987-2011)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Blended Global Sea Surface Winds products contain ocean surface wind vectors and wind stress on a global 0.25 degree grid, in multiple time resolutions of...

47 CFR 0.557 - Administrative review of an initial decision not to amend a record.

Science.gov (United States)

2010-10-01

... COMMISSION ORGANIZATION Privacy Act Regulations § 0.557 Administrative review of an initial decision not to... conduct an independent review of the record in controversy using the standards of review set out in § 0... expected to be completed. (c) If upon review of the record in controversy the Commission agrees with the...

Interfacial adhesion of nanoparticles in polymer blends by intrinsic fluorescence spectra

Directory of Open Access Journals (Sweden)

2011-09-01

Full Text Available Intrinsic fluorescence was applied to quantitatively describe the interfacial adhesion of nanoparticles in polystyrene/poly(vinyl methyl ether (PS/PVME blends. Due to the aggregation of aromatic rings on PS chains, the temperature dependence of excimer fluorescence intensity (I324 showed the high sensitivity to the phase separation process. Consistent with Ginzburg thermodynamic model, it was found that the addition of spherical hydrophilic nanoparticles shifted the phase separation temperature to higher temperatures due to the aggregation of silica into PVME chains leading to the free energy reduction and slowing down the phase separation dynamics. A certain composition of polymer blend, i.e. 2/8, was focused on to shed light on the dynamic of spinodal decomposition (SD phase separation by using decomposition reaction model. It was shown that the addition of nanoparticles to polymer blends resulted in the deviation of linear relationship between the initial SD phase separation rate (Rp0 and thermodynamic driving force (ΔfSD. Besides, for PS/PVME (2/8 with 2 vol% silica nanoparticles, the apparent activation energy of phase separation (Ea was 196.61 kJ/mol, which was higher than that of neat PS/PVME (2/8 blend (Ea = 173.68 kJ/mol, which strongly confirmed the interfacial adhesion effect of silica nanoparticles as compatibilizers.

Polyethylene/hydrophilic polymer blends for biomedical applications.

Science.gov (United States)

Brynda, E; Houska, M; Novikova, S P; Dobrova, N B

1987-01-01

Polyethylene blends with poly(2-hydroxyethyl methacrylate) [poly(HEMA)] or poly(2,3-dihydroxypropyl methacrylate) [poly(DHPMA)] were prepared by swelling polyethylene with HEMA or 2,3-epoxypropyl methacrylate (EPMA) and by polymerization of the respective monomers. Poly(EPMA) in blends was hydrolysed to poly(DHPMA) with acetic acid. The blends had similar surface and bulk compositions. Swelling with water and surface wettability were proportional to the content of the hydrophilic component; at the same content the polyethylene/poly(DHPMA) blends appeared more hydrophilic than those of polyethylene/poly(HEMA). Thrombus formation in contact with blood examined ex vivo and in vivo was considerably slower on the blends than on unmodified polyethylene. The tests indicated optima in composition; the best biological response was achieved with the blends containing about 14% poly(HEMA) or 16% poly(DHPMA).

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

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

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.

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

International Nuclear Information System (INIS)

1995-09-01

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

Experimental investigation of CI engine combustion, performance and emissions in DEE–kerosene–diesel blends of high DEE concentration

International Nuclear Information System (INIS)

Patil, K.R.; Thipse, S.S.

2015-01-01

Highlights: • First ever study on DEE–kerosene–diesel blends used in CI engine. • DEE–diesel blends have reduced the trade-off between PM and NOx of diesel engine. • Optimum performance blend has been found as DE15D. • Adulteration effects of kerosene with diesel have also been investigated. • Additions of kerosene with DE15D blend have deteriorated the overall engine performance. - Abstract: An experimental investigation had been carried out to evaluate the effects of oxygenated cetane improver diethyl ether (DEE) blends with kerosene and diesel on the combustion, performance and emission characteristics of a direct injection diesel engine. Initially, 2%, 5%, 8%, 10%, 15%, 20% and 25% DEE (by volume) were blended into diesel. The DEE–diesel blends have reduced the trade-off between PM and NOx of diesel engine and the optimum performance blend has been found as DE15D. Similarly, 5%, 10% and 15% kerosene (by volume) were blended into diesel to investigate the adulteration effect. In addition, a study was carried out to evaluate the effects of kerosene adulteration on DE15D by blending with 5%, 10% and 15% kerosene (by volume). The engine tests were carried out at 10%, 25%, 50%, 75% and 100% of full load for all test fuels. Laboratory fuel tests showed that the DEE is completely miscible with diesel and kerosene in any proportion. It was observed that the density, kinematic viscosity and calorific value of the blends decreases, while the oxygen content and cetane number of the blends increases with the concentration of DEE addition. The experimental test results showed that the DEE–kerosene–diesel blends have low brake thermal efficiency, high brake specific fuel consumption, high smoke at full load, low smoke at part load, overall low NO, almost similar CO, high HC at full load and low HC at part load as compared to DE15D blend

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

International Nuclear Information System (INIS)

1995-09-01

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

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

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

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.

Viscoelastic properties of PLA/PCL blends compatibilized with different methods

Science.gov (United States)

Shin, Boo Young; Han, Do Hung

2017-11-01

The aim of this study was to observe changes in the viscoelastic properties of PLA/PCL (80/20) blends produced using different compatibilization methods. Reactive extrusion and high-energy radiation methods were used for blend compatibilization. Storage and loss moduli, complex viscosity, transient stress relaxation modulus, and tan δ of blends were analyzed and blend morphologies were examined. All compatibilized PLA/PCL blends had smaller dispersed particle sizes than the non-compatibilized blend, and well compatibilized blends had finer morphologies than poorly compatibilized blends. Viscoelastic properties differentiated well compatibilized and poorly compatibilized blends. Well compatibilized blends had higher storage and loss moduli and complex viscosities than those calculated by the log-additive mixing rule due to strong interfacial adhesion, whereas poorly compatibilized blends showed negative deviations due to weak interfacial adhesion. Moreover, well compatibilized blends had much slower stress relaxation than poorly compatibilized blends and didn't show tan δ plateau region caused by slippage at the interface between continuous and dispersed phases.

Mechanical properties of irradiated rubber-blends

International Nuclear Information System (INIS)

Nasr, G.M.; Madani, M.

2005-01-01

A study has been made on blend ratios of natural rubber (NR) and acrylonitrile butadiene rubber (NBR) that are loaded with general purpose furnace (GPE) carbon black and irradiated at different gamma radiation doses. It was fount that the mechanical properties of such blend are highly affected by γ- irradiation dose and the composition ratios of its constituents. The elongation at break for blends was found to increase slightly with increasing NBR loafing which is mainly due to the stiffness of blending matrix formation between NR and GPF carbon black particles. The hysteresis loss, extension ratio and shape factor have been calculated for the different un-irradiated and irradiated samples

Binary blend Nanoparticles with defined morphology

International Nuclear Information System (INIS)

Ghazy, O.A.H.

2008-01-01

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

Combustion behavior of different kinds of torrefied biomass and their blends with lignite.

Science.gov (United States)

Toptas, Asli; Yildirim, Yeliz; Duman, Gozde; Yanik, Jale

2015-02-01

In this study, the combustion behavior of different kinds of torrefied biomass (lignocellulosic and animal wastes) and their blends with lignite was investigated via non-isothermal thermogravimetric method under air atmosphere. For comparison, combustion characteristics of raw biomasses were also determined. Torrefaction process improved the reactivity of char combustion step of biomasses. Characteristic combustion parameters for blends showed non-additivity behavior. It was found that the mixture of torrefied biomasses and lignite at a ratio of 1:1 had a lower ignition and burnout temperature than the coal-only sample. Although no interactions were observed between the lignite and torrefied biomass at initial step of combustion, a certain degree of interaction between the components occurred at char combustion step. Kinetic parameters of combustion were calculated by using the Coats Redfern model. Overall, this study showed that poultry litters can be used as a substitute fuel in coal/biomass co-firing systems by blending with lignocellulosic biomass. Copyright © 2014 Elsevier Ltd. All rights reserved.

Blended Learning from Design to Evaluation: International Case Studies of Evidence-Based Practice

Science.gov (United States)

Vaughan, Norman; Reali, Aline; Stenbom, Stefan; Van Vuuren, Marieta Jansen; MacDonald, David

2017-01-01

This study compares and contrasts four international faculty development programs for blended learning in order to understand the benefits, challenges, lessons learned, and recommendations from such initiatives. The benefits identified for faculty members, who participated in these programs, were that they became more reflective of their teaching…

Face-to-Face Activities in Blended Learning

DEFF Research Database (Denmark)

Kjærgaard, Annemette

While blended learning combines online and face-to-face teaching, research on blended learning has primarily focused on the role of technology and the opportunities it creates for engaging students. Less focus has been put on face-to-face activities in blended learning. This paper argues...... that it is not only the online activities in blended learning that provide new opportunities for rethinking pedagogy in higher education, it is also imperative to reconsider the face-to-face activities when part of the learning is provided online. Based on a review of blended learning in business and management...... education, we identify what forms of teaching and learning are suggested to take place face-to-face when other activities are moved online. We draw from the Community of Inquiry framework to analyze how face-to-face activities contribute to a blended learning pedagogy and discuss the implications...

BLENDED LEARNING STRATEGY IN TEACHER TRAINING PROGRAMS

Directory of Open Access Journals (Sweden)

Marian F. Byrka

2017-12-01

Full Text Available The article examines the implementation of blended learning strategy in teacher training programs as an innovation in online learning. The blended learning idea comes from blending elements which use online technology with more traditional face-to-face teaching in the same course. The article analyses teacher training programs offered by Chernivtsi Regional Institute of Postgraduate Pedagogical Education. Additional data were gathered through a questionnaire administered to teachers who attended training courses. The characteristics of blended learning strategy, its benefits and limitations for teacher training are supported by a review of literature. The article closes with the comparison of curriculum components (content delivery, learner activities, materials, and required competences between traditional and blended learning teacher training programs. Having obvious benefits in teacher training programs, the implementation of blended learning strategy sets some additional requirements to a learner, as well as to course instructors and lectors.

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..., DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Other Than Standard Wine § 24.213 Heavy bodied blending wine. Heavy bodied blending wine is wine made for blending purposes from grapes or other fruit without...

[Blending powdered antineoplastic medicine in disposable ointment container].

Science.gov (United States)

Miyazaki, Yasunori; Uchino, Tomonobu; Kagawa, Yoshiyuki

2014-01-01

On dispensing powdered antineoplastic medicines, it is important to prevent cross-contamination and environmental exposure. Recently, we developed a method for blending powdered medicine in a disposable ointment container using a planetary centrifugal mixer. The disposable container prevents cross-contamination. In addition, environmental exposure associated with washing the apparatus does not arise because no blending blade is used. In this study, we aimed to confirm the uniformity of the mixture and weight loss of medicine in the blending procedure. We blended colored lactose powder with Leukerin(®) or Mablin(®) powders using the new method and the ordinary pestle and mortar method. Then, the blending state was monitored using image analysis. Blending variables, such as the blending ratio (1:9-9:1), container size (35-125 mL), and charging rate (20-50%) in the container were also investigated under the operational conditions of 500 rpm and 50 s. At a 20% charging rate in a 35 mL container, the blending precision of the mixtures was not influenced by the blending ratio, and was less than 6.08%, indicating homogeneity. With an increase in the charging rate, however, the blending precision decreased. The possible amount of both mixtures rose to about 17 g with a 20% charging rate in a 125 mL container. Furthermore, weight loss of medicines with this method was smaller than that with the pestle and mortar method, suggesting that this method is safer for pharmacists. In conclusion, we have established a precise and safe method for blending powdered medicines in pharmacies.

Tracing the combustion of coal blends in a thermobalance by optical microscopy

Energy Technology Data Exchange (ETDEWEB)

E. Osorio; M.L.F. Ghiggi; A.C.F. Vilela; W.D. Kalkreuth; D. Alvarez; A.G. Borrego [Universidade Federal do Rio Grande do Sul, Porto Alegre (Brazil). Laboratorio de Siderurgia

2007-07-01

Combustion at programmed temperature in a thermobalance is a common test for the rapid assessment of coal combustibility. In this study two series of blends (low rank/medium rank coal-AB and low rank /petroleum coke-AC) with the low rank coal in three different proportions (1/4, 2/4 and 3/4) have been tested. Samples have been ground and sieved to 20-75 m prior to blend preparation. The combustion profiles indicated different behaviour for the two series of samples: the AB series showed wide curves with the presence of shoulders whereas the AC series showed two maxima corresponding to the component fuels. The comparison of the calculated and experimental curves indicated different effects of blending on the relevant temperatures and reactivity of the blends. In the AB blend both initial and peak temperatures were lower than expected and the higher the proportion of low rank coal, the larger the difference. In the AC series the burnout temperature was the parameter departing more from the expected values. In order to visualize relative combustibility of the coals the reaction was stopped at 50% conversion and the samples were examined through the microscope. The combustion of the particles followed a shrinking core pattern in which the core of the low rank particles remained isotropic whereas anisotropy development was observed in the medium rank coal. The reflectance of the coals increased with increasing the temperature at which the reaction was stopped regardless the rank of the parent coal following a linear trend. 5 refs., 5 figs., 1 tab.

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

Directory of Open Access Journals (Sweden)

Nuray Gedik

2012-03-01

Full Text Available 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 reşection papers, interviews with students, and documents, and analyzed by structurally and texturally describing the resulting experiences and perceptions. The findings of the study indicate that used together, online and face-to-face course structures offer several opportunities and challenges for students. The participating students mentioned interaction and communication opportunities, increased motivation, increased opportunities to voice their opinions, and reinforcement of learning as the affordances in the blended learning environment. The barriers included increased workload, cultural and technical barriers, and the inter-dependence of the two environments. Implications and suggestions are offered for instructors in higher education settings

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

Directory of Open Access Journals (Sweden)

Nuray Gedik

2012-07-01

Full Text Available 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 texturally describing the resulting experiences and perceptions. The findings of the study indicate that used together, online and face-to-face course structures offer several opportunities and challenges for students. The participating students mentioned interaction and communication opportunities, increased motivation, increased opportunities to voice their opinions, and reinforcement of learning as the affordances in the blended learning environment. The barriers included increased workload, cultural and technical barriers, and the inter-dependence of the two environments. Implications and suggestions are offered for instructors in higher education settings.

Wavelet and Blend maps for texture synthesis

OpenAIRE

Du Jin-Lian; Wang Song; Meng Xianhai

2011-01-01

blending is now a popular technology for large realtime texture synthesis .Nevertheless, creating blend map during rendering is time and computation consuming work. In this paper, we exploited a method to create a kind of blend tile which can be tile together seamlessly. Note that blend map is in fact a kind of image, which is Markov Random Field, contains multiresolution signals, while wavelet is a powerful way to process multiresolution signals, we use wavelet to process the traditional ble...

Review Of Rheology Models For Hanford Waste Blending

Energy Technology Data Exchange (ETDEWEB)

Koopman, D. C.; Stone, M.

2013-09-26

The area of rheological property prediction was identified as a technology need in the Hanford Tank Waste - waste feed acceptance initiative area during a series of technical meetings among the national laboratories, Department of Energy-Office of River Protection, and Hanford site contractors. Meacham et al. delivered a technical report in June 2012, RPP-RPT-51652 ''One System Evaluation of Waste Transferred to the Waste Treatment Plant'' that included estimating of single shell tank waste Bingham plastic rheological model constants along with a discussion of the issues inherent in predicting the rheological properties of blended wastes. This report was selected as the basis for moving forward during the technical meetings. The report does not provide an equation for predicting rheological properties of blended waste slurries. The attached technical report gives an independent review of the provided Hanford rheological data, Hanford rheological models for single tank wastes, and Hanford rheology after blending provided in the Meacham report. The attached report also compares Hanford to SRS waste rheology and discusses some SRS rheological model equations for single tank wastes, as well as discussing SRS experience with the blending of waste sludges with aqueous material, other waste sludges, and frit slurries. Some observations of note: Savannah River Site (SRS) waste samples from slurried tanks typically have yield stress >1 Pa at 10 wt.% undissolved solids (UDS), while core samples largely have little or no yield stress at 10 wt.% UDS. This could be due to how the waste has been processed, stored, retrieved, and sampled or simply in the differences in the speciation of the wastes. The equations described in Meacham's report are not recommended for extrapolation to wt.% UDS beyond the available data for several reasons; weak technical basis, insufficient data, and large data scatter. When limited data are available, for example two to

Silk fibroin/pullulan blend films: Preparation and characterization

Energy Technology Data Exchange (ETDEWEB)

Shivananda, C. S.; Rao, B. Lakshmeesha; Madhukumar, R.; Asha, S. [Department of Studies in Physics, Mangalore University, Mangalagangotri – 574 199 (India); Sarojini, B. K. [Department of Industrial Chemistry, Mangalore University, Mangalagangotri, Mangalore –574 199 (India); Somashekhar, R. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore – 570 006 (India); Sangappa, Y., E-mail: syhalabhavi@yahoo.co.in [Department of Studies in Physics, Mangalore University, Mangalagangotri – 574 199 (India); School of Material Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States)

2016-05-23

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.

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.

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.

75 FR 54020 - Federal Housing Administration Risk Management Initiatives: New Loan-to-Value and Credit Score...

Science.gov (United States)

2010-09-03

... Housing Administration Risk Management Initiatives: New Loan-to-Value and Credit Score Requirements AGENCY... acceptable risks of financial loss, not unacceptable risks.\\2\\ \\2\\ While the Federal Credit Reform Act of..., specific to each applicant. Lower credit scores indicate greater risk of default on any new credit extended...

Moisture sorption and thermal characteristics of polyaramide blend fabrics

OpenAIRE

Genç, Gözde; Alp, Burcu; Balköse, Devrim; Ülkü, Semra; Cireli, Aysun

2006-01-01

Four types of fabrics woven from various polyaramid fibers of Nomex and Kevlar blends were characterized by morphology, XRD, elemental analysis, thermal analysis, and moisture adsorption isotherms. The blends consisted of Polybenzimidazole/ Kevlar blend (40% FBI and 60% Kevlar®), Nomex Delta A (blend of 60% Kevlar and 40% Nomex®), Nomex Delta T (blend of 75% Nomex, 23% Kevlar, and 2% P140 antistatic fiber), and Nomex III (fabric with a 95/5 blend of Nomex and Kevlar) containing 1% steel fiber...

HIGHLY ENRICHED URANIUM BLEND DOWN PROGRAM AT THE SAVANNAH RIVER SITE PRESENT AND FUTURE

International Nuclear Information System (INIS)

Magoulas, V; Charles Goergen, C; Ronald Oprea, R

2008-01-01

The Department of Energy (DOE) and Tennessee Valley Authority (TVA) entered into an Interagency Agreement to transfer approximately 40 metric tons of highly enriched uranium (HEU) to TVA for conversion to fuel for the Browns Ferry Nuclear Power Plant. Savannah River Site (SRS) inventories included a significant amount of this material, which resulted from processing spent fuel and surplus materials. The HEU is blended with natural uranium (NU) to low enriched uranium (LEU) with a 4.95% 235U isotopic content and shipped as solution to the TVA vendor. The HEU Blend Down Project provided the upgrades needed to achieve the product throughput and purity required and provided loading facilities. The first blending to low enriched uranium (LEU) took place in March 2003 with the initial shipment to the TVA vendor in July 2003. The SRS Shipments have continued on a regular schedule without any major issues for the past 5 years and are due to complete in September 2008. The HEU Blend program is now looking to continue its success by dispositioning an additional approximately 21 MTU of HEU material as part of the SRS Enriched Uranium Disposition Project

Using Blended Teaching to Teach Blended Learning: Lessons Learned from Pre-Service Teachers in an Instructional Methods Course

Science.gov (United States)

Shand, Kristen; Farrelly, Susan Glassett

2017-01-01

In this study, we explore the design and delivery of a blended social studies teaching methods course to examine the elements of the blended design that pre-service teachers found most constructive. In focus groups at the completion of the course, pre-service teachers were asked to reflect on their experience in the blended course, identify the…

LENRA as compatibilizer in NR/HDPE blends

International Nuclear Information System (INIS)

Dahlan Mohd; Mahathir Mohamed

2006-01-01

Polymer blends of 60/40 NR/RDPE were prepared using Brabender PL2000 Plasticorder with 60 g capacity. The blends were added with radiation-sensitive natural rubber (NR)-based compatibilizer, known as LENRA. They were irradiated with electron-beam radiation at various doses. The efficacy of the compatibilizer was monitored by measuring various properties of the blends such as physical and dynamic mechanical properties including morphological studies by electron microscopic technique. Early results show that the addition of LENRA improves the properties of the TPNR blends. (Author)

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 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 Blended exercise physiology laboratories provided an alternative method for delivering content that was favorably perceived by students and did not compromise student performance. Copyright © 2016 The American Physiological Society.

EFFECTIVE BLENDED LEARNING PRACTICES: Evidence-based Perspectives in ICT-facilitated Education

Directory of Open Access Journals (Sweden)

Reviewed by Yasin OZARSLAN

2009-07-01

Full Text Available EFFECTIVE BLENDED LEARNING PRACTICES:Evidence-based Perspectives in ICT-facilitated EducationEdited by Elizabeth Stacey and Philippa Gerbic, Information ScienceReference; 1 edition (March 30, 2009, ISBN-10: 1605662968, 358 pp.Reviewed by Yasin OZARSLANFaculty of Education,Eskisehir Osmangazi University,Eskisehir-TURKEYBlended learning refers to the integration of faceto-face and online learning activities with the goal of maximizing the value of students' experiences in both settings. This book collects new international research into many aspects of blended learningfrom the perspectives of learners, teachers, designers, and professional and academic developers in various disciplines, learningcommunities and universities from around the world. This book addresses the relative newness of online learning within blended environments. The book's broader audience is anyone who isinterested in areas such as blended learning, communities of learning, virtual education, professional learning and community development, instructional technology, flexible learning, distance education and collaborative learning.Blended approaches in teacher education, blending collaborative online learning,blended learning and teaching philosophies, campus-based student learning environments, ICT-enhanced blended learning, learning communities for K-12 teachers, professional development for blended learning, reciprocal mentoring,redesigning initial teacher education, responses to blended environments, strategiesfor blended teaching and learning, virtual learning and real communities are the topics covered in this book.It reviews literature about blended learning in relation to the three sections of the book and discusses strategies for teaching and learning and establishing communities in its different contexts. The chapters of this book provide research perspectives on a range of blended learning issues and contexts and discuss implications for teaching and learning. The

A Phase Blending Study on Rubber Blends Based on the Solubility Preference of Curatives

NARCIS (Netherlands)

Guo, R.; Talma, Auke; Datta, Rabin; Dierkes, Wilma K.; Noordermeer, Jacobus W.M.

2009-01-01

Using previously obtained data on the solubilities of curatives in SBR, EPDM and in NBR, different mixing procedures were performed on 50/50 SBR/EPDM and NBR/EPDM blends. In contrast to a previous phase-mixing study, the curatives were added to separate phases before final blending, in an attempt to

Blended Learning: An Innovative Approach

Science.gov (United States)

Lalima; Dangwal, Kiran Lata

2017-01-01

Blended learning is an innovative concept that embraces the advantages of both traditional teaching in the classroom and ICT supported learning including both offline learning and online learning. It has scope for collaborative learning; constructive learning and computer assisted learning (CAI). Blended learning needs rigorous efforts, right…

LENRA as compatibilizer in NR/HDPE blends

International Nuclear Information System (INIS)

Mahathir Mohamed; Dahlan Mohd

2004-01-01

Polymer blends of 60/40 NR/HDPE were prepared using Brabender PL2000 plasticorder with 60g capacity. The blends were added with radiation sensitive natural rubber (NR)-based compatibilizer, known as LENRA. They were irradiated in air with electron beam radiation at various doses. The efficacy of the compatibilizer was monitored by measuring various properties of the blends such as physical and dynamic mechanical properties including morphological studies by electron microscopic technique. Early results show that the addition of LENRA improves the properties of the TPNR blends. (Author)

Effect of intravenous administration of D-lysergic acid diethylamide on initiation of protein synthesis in a cell-free system derived from brain.

Science.gov (United States)

Cosgrove, J W; Brown, I R

1984-05-01

An initiating cell-free protein synthesis system derived from brain was utilized to demonstrate that the intravenous injection of D-lysergic acid diethylamide (LSD) to rabbits resulted in a lesion at the initiation stage of brain protein synthesis. Three inhibitors of initiation, edeine, poly(I), and aurintricarboxylic acid were used to demonstrate a reduction in initiation-dependent amino acid incorporation in the brain cell-free system. One hour after LSD injection, there was also a measurable decrease in the formation of 40S and 80S initiation complexes in vitro, using either [35S]methionine or [35S]Met-tRNAf. Analysis of the methionine pool size after LSD administration indicated there was no change in methionine levels. Analysis of the formation of initiation complexes in the brain cell-free protein synthesis system prepared 6 h after LSD administration indicated that there was a return to control levels at this time. The effects of LSD on steps in the initiation process are thus reversible.

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

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…

Empowering Learners through Blended Learning

Science.gov (United States)

Owston, Ron

2018-01-01

Blended learning appears to facilitate learner empowerment more readily than either face-to-face or fully online courses. This contention is supported by a review of literature on the affordances of blended learning that support Thomas and Velthouse's (1990) four conditions of empowerment: choice, meaningfulness, competence, and impact. Blended…

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…

Development of the Indigenous Child-Initiated Pretend Play Assessment: Selection of play materials and administration.

Science.gov (United States)

Dender, Alma; Stagnitti, Karen

2011-02-01

There is a need for culturally appropriate assessments for Australian Indigenous children. This article reports the selection of culturally appropriate and gender-neutral play materials, and changes in administration identified to develop further the Indigenous Child-Initiated Pretend Play Assessment (I-ChIPPA). Twenty-three typically developing children aged four to six years from the Pilbara region in Western Australia participated in the study. Children were presented with four sets of play materials and frequency counts were recorded for each time the child used one of the play materials in a pretend play action. Twelve of the 23 children came to play in pairs. Both boys and girls used the Pilbara toy set including the dark coloured dolls and Pilbara region animals, more frequently than the standardised play materials from the Child-Initiated Pretend Play Assessment (ChIPPA). This study reports the first steps in the development of the I-ChIPPA. Future development will include the refinement of the administration and scoring with pairs of children, and then validity testing the assessment. © 2010 The Authors. Australian Occupational Therapy Journal © 2010 Australian Association of Occupational Therapists.

The Art of Blending: Benefits and Challenges of a Blended Course for Preservice Teachers

Science.gov (United States)

Shand, Kristen; Farrelly, Susan Glassett

2018-01-01

In this study, we explore the design and delivery of a blended social studies teaching methods course according to principles and core attributes of blended course design. In a survey at the end of the course, pre-service teachers were asked to reflect on their experience in the course, and identify the benefits and challenges of the blended…

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

International Nuclear Information System (INIS)

Lee, S.; Leishear, R.; Poirier, M.

2012-01-01

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.

Silk fibroin membranes from solvent-crystallized silk fibroin/gelatin blends: Effects of blend and solvent composition

Energy Technology Data Exchange (ETDEWEB)

Gil, Eun S. [Fiber and Polymer Science Program, North Carolina State University, Raleigh, NC 27695 (United States); Frankowski, David J. [Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695 (United States); Hudson, Samuel M. [Fiber and Polymer Science Program, North Carolina State University, Raleigh, NC 27695 (United States); Spontak, Richard J. [Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695 (United States) and Department of Materials Science and Engineering, North Carolina State University, Raleigh, NC 27695 (United States)]. E-mail: Rich_Spontak@ncsu.edu

2007-04-15

Protein membranes have been prepared by mixing gelatin (G) with Bombyx mori silk fibroin (SF) and using aqueous methanol (MeOH) to induce SF crystallization. Amorphous blends of these polymers appear quasi-homogeneous, as discerned from visual observation, electron microscopy and Fourier-transform infrared (FTIR) spectroscopy. Upon subsequent exposure to aqueous MeOH, SF undergoes a conformational change from random-coil to {beta}-sheet. This transformation occurs in pure SF, as well as in each of the G/SF blends, as discerned from FTIR spectroscopy and thermal calorimetry. The influence of MeOH-induced SF crystallization on structure and property development has been measured as functions of blend and solvent composition. By preserving a support scaffold above the G helix-to-coil transition temperature, the formation of crystalline SF networks in G/SF blends can be used to stabilize G-based hydrogels or generate SF membranes for biomaterial, pharmaceutical and gas-separation purposes. The present study not only examines the properties of G/SF blends before and after SF crystallization, but also establishes the foundation for future research into thermally-responsive G/SF bioconjugates.

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.

A blended learning approach to teaching basic pharmacokinetics and the significance of face-to-face interaction.

Science.gov (United States)

Edginton, Andrea; Holbrook, Jane

2010-06-15

To assess pharmacy students' attitudes towards a blended-learning pharmacokinetics course. Narrated visual presentations and animations that illustrated kinetic processes and guided students through the use of software programs used for calculations were created. Other learning techniques used included online self-assessment quizzes, practice problem sets, and weekly face-to-face problem-solving tutorials. A precourse questionnaire to assess students' level of enthusiasm towards the blended-learning course and to solicit any concerns they had was administered at the beginning of the course. A postcourse questionnaire that included the same 4 Likert-scale items from the precourse questionnaire and follow-up open-ended questions was administered. Individual changes in level of enthusiasm were compared for individuals who completed both the precourse and postcourse questionnaire. Students' concerns about the blended method of learning had decreased postcourse while their enthusiasm for the benefits of blended learning had increased. Students' initial concerns about the blended learning experience were focused on their ability to communicate with the instructor about the online components, but shifted to their own time management skills at the end of the course. Face-to-face interactions with each other and with the instructor were more highly rated than online interactions in this course.

Perceptions of sport science students on the potential applications and limitations of blended learning in their education: a qualitative study.

Science.gov (United States)

Keogh, Justin W L; Gowthorp, Lisa; McLean, Michelle

2017-09-01

This study sought to gain insight into blended learning-naive sports science students' understanding and perceptions of the potential benefits and limitations of blended (hybrid) learning, which has been defined as the thoughtful integration of face-to-face and online instructional approaches. Five focus groups, each comprising 3-4 students from either the undergraduate or postgraduate sports science programmes were conducted. The focus groups were facilitated by a researcher who was not involved in sports science. Audio recordings of the focus groups were transcribed verbatim. NVivo software was used to code the transcripts to identify the themes and subthemes. Students generally had little initial understanding of blended learning. When provided with a definition, they believed that blended learning could improve educational outcomes and assist those who were legitimately unable to attend a session. Their reservations about blended learning mainly related to some students not being sufficiently autonomous to undertake independent study, timetabling considerations and access to reliable Internet services. For blended learning to be effective, students felt the online material had to be interactive, engaging and complement the face-to-face sessions. Better understanding the perceptions of the students in the current study may assist educators who are considering implementing blended learning in their teaching.

The processing of blend words in naming and sentence reading.

Science.gov (United States)

Johnson, Rebecca L; Slate, Sarah Rose; Teevan, Allison R; Juhasz, Barbara J

2018-04-01

Research exploring the processing of morphologically complex words, such as compound words, has found that they are decomposed into their constituent parts during processing. Although much is known about the processing of compound words, very little is known about the processing of lexicalised blend words, which are created from parts of two words, often with phoneme overlap (e.g., brunch). In the current study, blends were matched with non-blend words on a variety of lexical characteristics, and blend processing was examined using two tasks: a naming task and an eye-tracking task that recorded eye movements during reading. Results showed that blend words were processed more slowly than non-blend control words in both tasks. Blend words led to longer reaction times in naming and longer processing times on several eye movement measures compared to non-blend words. This was especially true for blends that were long, rated low in word familiarity, but were easily recognisable as blends.

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

International Nuclear Information System (INIS)

Holmes, David R.; Fletcher, Joel G.; Apel, Anja; Huprich, James E.; Siddiki, Hassan; Hough, David M.; Schmidt, Bernhard; Flohr, Thomas G.; Robb, Richard; McCollough, Cynthia; Wittmer, Michael; Eusemann, Christian

2008-01-01

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

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…

Using Virtual Laboratories as Interactive Textbooks: Studies on Blended Learning in Biotechnology Classrooms

Directory of Open Access Journals (Sweden)

Hemalatha Sasidharakurup

2015-07-01

Full Text Available Virtual laboratories, an ICT-based initiative, is a new venture that is becoming more prevalent in universities for improving classroom education. With geographically remote and economically constrained institutes in India as the focus, we developed web-based virtual labs for virtualizing the wet-lab techniques and experiments with the aid of graphics favoured animations, mathematical simulators and remote triggered experimentations. In this paper, we analysed perceived usefulness of Biotechnology virtual labs amongst student groups and its role in improving the student’s performance when introduced as a learning tool in a blended classroom scenario. A pedagogical survey, via workshops and online feedback, was carried out among 600 university-level students and 100 remote users of various Indian universities. Comparing learning groups on usage of blended learning approach against a control group (traditional classroom methods and an experimental group (teacher-mediated virtual labs, our studies indicate augmented academic performance among students in blended environments. Findings also indicated usage of remotely-triggered labs aided enhancing interaction-based lab education enabling anytime-anywhere student participation scenarios.

Radiation processing of thermoplastic starch by blending aromatic additives: Effect of blend composition and radiation parameters

Science.gov (United States)

Khandal, Dhriti; Mikus, Pierre-Yves; Dole, Patrice; Coqueret, Xavier

2013-03-01

This paper reports on the effects of electron beam (EB) irradiation on poly α-1,4-glucose oligomers (maltodextrins) in the presence of water and of various aromatic additives, as model blends for gaining a better understanding at a molecular level the modifications occurring in amorphous starch-lignin blends submitted to ionizing irradiation for improving the properties of this type of bio-based thermoplastic material. A series of aromatic compounds, namely p-methoxy benzyl alcohol, benzene dimethanol, cinnamyl alcohol and some related carboxylic acids namely cinnamic acid, coumaric acid, and ferulic acid, was thus studied for assessing the ability of each additive to counteract chain scission of the polysaccharide and induce interchain covalent linkages. Gel formation in EB-irradiated blends comprising of maltodextrin was shown to be dependent on three main factors: the type of aromatic additive, presence of glycerol, and irradiation dose. The chain scission versus grafting phenomenon as a function of blend composition and dose were studied using Size Exclusion Chromatography by determining the changes in molecular weight distribution (MWD) from Refractive Index (RI) chromatograms and the presence of aromatic grafts onto the maltodextrin chains from UV chromatograms. The occurrence of crosslinking was quantified by gel fraction measurements allowing for ranking the cross-linking efficiency of the additives. When applying the method to destructurized starch blends, gel formation was also shown to be strongly affected by the moisture content of the sample submitted to irradiation. The results demonstrate the possibility to tune the reactivity of tailored blend for minimizing chain degradation and control the degree of cross-linking.

Characterization of polycaprolactone and starch blends for potential ...

African Journals Online (AJOL)

Thermally blending starch and polycaprolactone with the compatibilizer methylenediphenyl diisocyanate (MDI) distributed in the polyester phase had been previously confirmed to enhance the mechanical properties and interface between the two phases of the blends. In this study, blends of polycaprolactone with various ...

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.

BLENDED LEARNING COURSE FOR FUTURE PRIMARY SCHOOL TEACHERS IMPLEMENTATION

Directory of Open Access Journals (Sweden)

Vira V. Kotkova

2017-09-01

Full Text Available Ukrainian and foreign scientists’ views on the essence of blended learning are analyzed in the article. The author's definition of a blended learning course is presented. The process of such course designing is described according to target, motivational, substantive, operational and diagnostic components. Both the structure of the blended learning course implementation as well as students’ educational-cognitive activity distribution between classroom learning and distance course are shown. The problems for students, teachers, and educational institutions of blended courses effective implementation are summarized. Students’ academic performance of three years study is analyzed. The results of students’ questioning to determine their perception of blended learning course are described according to the following categories: the effectiveness of blended course, evaluation objectivity, motivation to study, the use of plagiarism in studies, understanding of blended learning course.

Morphology development in immiscible polymer blends

NARCIS (Netherlands)

Cardinaels, R.M.; Moldenaers, P.; Guo, Qipeng

This chapter discusses the morphology development of immiscible binary polymer blends. It first describes morphology development in droplet-matrix structures, the dynamics of fibrillar structures and cocontinuous structures. The chapter then considers binary immiscible polymer blends, such systems

Synthesis of geopolymer from biomass-coal ash blends

Science.gov (United States)

Samadhi, Tjokorde Walmiki; Wulandari, Winny; Prasetyo, Muhammad Iqbal; Fernando, Muhammad Rizki; Purbasari, Aprilina

2017-09-01

Geopolymer is an environmentally attractive Portland cement substitute, owing to its lower carbon footprint and its ability to consume various aluminosilicate waste materials as its precursors. This work describes the development of geopolymer formulation based on biomass-coal ash blends, which is predicted to be the prevalent type of waste when biomass-based thermal energy production becomes mainstream in Indonesia. The ash blends contain an ASTM Class F coal fly ash (FA), rice husk ash (RHA), and coconut shell ash (CSA). A mixture of Na2SiO3 and concentrated KOH is used as the activator solution. A preliminary experiment identified the appropriate activator/ash mass ratio to be 2.0, while the activator Na2SiO3/KOH ratio varies from 0.8 to 2.0 with increasing ash blend Si/Al ratio. Both non-blended FA and CSA are able to produce geopolymer mortars with 7-day compressive strength exceeding the Indonesian national SNI 15-2049-2004 standard minimum value of 2.0 MPa stipulated for Portland cement mortars. Ash blends have to be formulated with a maximum RHA content of approximately 50 %-mass to yield satisfactory 7-day strength. No optimum ash blend composition is identified within the simplex ternary ash blend compositional region. The strength decreases with Si/Al ratio of the ash blends due to increasing amount of unreacted silicate raw materials at the end of the geopolymer hardening period. Overall, it is confirmed that CSA and blended RHA are feasible raw materials for geopolymer production..

Enzymatic degradation of polycaprolactone–gelatin blend

International Nuclear Information System (INIS)

Banerjee, Aditi; Chatterjee, Kaushik; Madras, Giridhar

2015-01-01

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. (paper)

EVA reactive blending with Si–H terminated polysiloxane by carbonyl hydrosilylation reaction: From compatibilised blends to crosslinking networks

International Nuclear Information System (INIS)

Bonnet, J.; Bounor-Legaré, V.; Alcouffe, P.; Cassagnau, P.

2012-01-01

A new and original method based on carbonyl hydrosilylation was developed to prepare ethylene-vinyl acetate (EVA)/polysiloxane polymer blends. This focused on the addition of hydrogenosilane groups (SiH) from polysiloxane to the carbonyl groups of EVA. The influence of the nature of the polysiloxane on blend properties was investigated by rheology and scanning electron microscopy. Mixing of a low viscosity polysiloxane with a high viscosity EVA matrix produced a two-phase morphology. The occurrence of the hydrosilylation reaction at the EVA/polysiloxane interface promoted a homogenisation of the blend depending on the molar ratio SiH/vinyl acetate groups, [SiH]/[VA], and the viscosity ratio of the blend. Two distinct behaviours were observed. The formation of a crosslinked network under shear was obtained for a low viscosity ratio between polysiloxane and EVA (λ polysiloxane/EVA = 4.0 × 10 −6 ) with a high concentration of SiH groups ([SiH]/[VA] = 0.5), while the formation of a compatibilised blend was observed for high molar mass polysiloxanes (Mn > 15,000 g mol −1 ) with a low concentration of SiH ([SiH]/[VA] −3 ). -- Highlights: ► Carbonyl hydrosilylation reaction was found to enhance EVA/polysiloxane immiscible blends. ► EVA crosslinking was obtained with a low molar mass polysiloxane. ► EVA compatibilisation was obtained with a high molar mass polysiloxane. ► Shear rate was found to improve the hydrosilylation reaction at the interface. ► A two-phase morphology of the blends was observed after reaction with fine polysiloxane nodules.

BioBlend.objects: metacomputing with Galaxy.

Science.gov (United States)

Leo, Simone; Pireddu, Luca; Cuccuru, Gianmauro; Lianas, Luca; Soranzo, Nicola; Afgan, Enis; Zanetti, Gianluigi

2014-10-01

BioBlend.objects is a new component of the BioBlend package, adding an object-oriented interface for the Galaxy REST-based application programming interface. It improves support for metacomputing on Galaxy entities by providing higher-level functionality and allowing users to more easily create programs to explore, query and create Galaxy datasets and workflows. BioBlend.objects is available online at https://github.com/afgane/bioblend. The new object-oriented API is implemented by the galaxy/objects subpackage. © The Author 2014. Published by Oxford University Press.

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.......,  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.......  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...

Evaluating a learning management system for blended learning in Greek higher education.

Science.gov (United States)

Kabassi, Katerina; Dragonas, Ioannis; Ntouzevits, Alexandra; Pomonis, Tzanetos; Papastathopoulos, Giorgos; Vozaitis, Yiannis

2016-01-01

This paper focuses on the usage of a learning management system in an educational institution for higher education in Greece. More specifically, the paper examines the literature on the use of different learning management systems for blended learning in higher education in Greek Universities and Technological Educational Institutions and reviews the advantages and disadvantages. Moreover, the paper describes the usage of the Open eClass platform in a Technological Educational Institution, TEI of Ionian Islands, and the effort to improve the educational material by organizing it and adding video-lectures. The platform has been evaluated by the students of the TEI of Ionian Islands based on six dimensions: namely student, teacher, course, technology, system design, and environmental dimension. The results of this evaluation revealed that Open eClass has been successfully used for blended learning in the TEI of Ionian Islands. Despite the instructors' initial worries about students' lack of participation in their courses if their educational material was made available online and especially in video lectures; blended learning did not reduce physical presence of the students in the classroom. Instead it was only used as a supplementary tool that helps students to study further, watch missed lectures, etc.

Reconciliation of Cahn-Hilliard predictions for spinodal decomposition lengthscales in polymer blends

Science.gov (United States)

Cabral, Joao

Spinodal decomposition (SD) of partially miscible polymer blends can yield well-defined nanostructures with prescribed lengthscales and connectivity, and applications ranging from membranes and scaffolds to photovoltaics. Cahn-Hilliard-Cook (CHC) theory estimates the initial, dominant SD wavenumber to be qm =√{G''/4 k } , where G'' is the second derivative of the free energy of mixing with respect to concentration and k is a structural parameter which can be computed from the segment lengths and volumes of monomer units. Tuning G'', with quench depth into the two phase region, for instance, should thus provide a facile and precise means for designing polymeric bicontinuous structures. The fulfillment of this potential rests on the thermodynamics of available polymer systems, coarsening kinetics, as well as engineering constraints. We extensively review experimental measurements of G'' in both one- and two-phase blend systems, and critically examine the accuracy of this fundamental prediction against achievements over the past 4 decades of polymer blend demixing. Despite widespread misconceptions in detecting and describing SD, we find the CHC relation to be remarkably accurate and conclude with design considerations and limitations for polymer nanostructures via SD, reflecting on John Cahn's contributions to the field.

A study of coal-solid waste blend reactivity

Directory of Open Access Journals (Sweden)

Nayibe Guerrero

2008-05-01

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.

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.

Comprehensive, Mixed-Methods Assessment of a Blended Learning Model for Geospatial Literacy Instruction

Science.gov (United States)

Brodeur, J. J.; Maclachlan, J. C.; Bagg, J.; Chiappetta-Swanson, C.; Vine, M. M.; Vajoczki, S.

2013-12-01

Geospatial literacy -- the ability to conceptualize, capture, analyze and communicate spatial phenomena -- represents an important competency for 21st Century learners in a period of 'Geospatial Revolution'. Though relevant to in-course learning, these skills are often taught externally, placing time and resource pressures on the service providers - commonly libraries - that are relied upon to provide instruction. The emergence of online and blended modes of instruction has presented a potential means of increasing the cost-effectiveness of such activities, by simultaneously reducing instructional costs, expanding the audience for these resources, and addressing student preferences for asynchronous learning and '24-7' access. During 2011 and 2012, McMaster University Library coordinated the development, implementation and assessment of blended learning modules for geospatial literacy instruction in first-year undergraduate Social Science courses. In this paper, we present the results of a comprehensive mixed-methods approach to assess the efficacy of implementing blended learning modules to replace traditional (face-to-face), library-led, first-year undergraduate geospatial literacy instruction. Focus groups, personal interviews and an online survey were used to assess modules across dimensions of: student use, satisfaction and accessibility requirements (via Universal Instructional Design [UID] principles); instructor and teaching staff perception of pedagogical efficacy and instructional effectiveness; and, administrator cost-benefit assessment of development and implementation. Results showed that both instructors and students identified significant value in using the online modules in a blended-learning setting. Reaffirming assumptions of students' '24/7' learning preferences, over 80% of students reported using the modules on a repeat basis. Students were more likely to use the modules to better understand course content than simply to increase their grade in

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.

Effect of aging in HDPE blended with DEM in decalin

International Nuclear Information System (INIS)

Silva, P.; Albano, C.; Karam, A.; Vargas, M.G.; Perera, R.

2006-01-01

Electron paramagnetic resonance (EPR) was used to study the effect of aging on irradiated samples of high-density polyethylene (HDPE) blended with diethyl maleate (DEM) in different proportions. Initially, we synthesize the HDPE using bis-(cyclopentadienyl) zirconium dichloride and P-MAO. The functionalization of the synthesized HDPE was carried out in a 10% weight/vol of polyethylene in decalin solution using different percentages of diethyl maleate (5, 10, 15 and 30% in weight). The samples were irradiated at 5, 15 and 30 kGy. An exponential decay in the total free radicals concentration was observed in the pure HDPE sample at the 15 and 30 kGy irradiation doses, as it was expected. For the 15 and 30 kGy irradiation doses the HDPE blended with 15 and 30% of DEM in decalin shows an increase in the total free radical concentrations as the storage time is increased. This behavior has been interpreted in terms of trapped free radicals. (Author)

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…

Potential Application of ENR/EPDM Blends

Directory of Open Access Journals (Sweden)

B.L. Chan

2017-06-01

Full Text Available Since the process and conversion of natural rubber into epoxidized natural rubber (ENR was discovered and patented by I. R. Gelling of the Malaysian Rubber Product Research Association  (or now known as the Tun Razak laboratory, Brickendonbury, Hertford, in the United Kingdom, there are more than 10 000 technical and technological papers cited in the internet. Information on ENR is available, not only in the the English language but also other languages like Chinese, Malay, French, Thai and even German languages are used. NR is the most versatile and reactive rubber/elastomer. It is an advanced natural rubber which could be potentially used as a starting material for the development of other rubbers, modifie elastomers, for grafting, plastic-based materials and also thermoplastic rubbers. Its reactivity is dependent on its epoxy groups, the opening of its ring structure, and also the subsequent structures of carboxylic groups and the in-situ side-chains “carbon – carbon” double bonds (> C = C <. In some instances, up to 65% epoxidation of NR is possible and achieved for more oil resistance. For these reasons, there are many new and advanced materials which have been formed and developed in the last two decades. Among them, some of the recent research work is listed here. Apart from studies of compounding the ENR itself and its potential uses, there are many rubber-rubber blends and ENR rubber-plastics blends, some of the studies cited are “uses of new and advanced chemicals”  and synthetic rubbers:  ENR/NBR, ENR/PVC, ENR/polylactic acid blends, ENR/copolyester blends, ENR/Copolyamide Blends, ENR/poly (vinylidene fluorideblends, ENR/Carbon Nanotubes with co-agent Trimethylol Propane Triacrylate, ENR /recycled silicon materials, and ENR/copolymer of n-butyl acrylate/butyl methacrylate “grafted”. Each of these blends has its own characteristics in terms of processing, enhancement of processing like safety, scorch, oil and water

Teaching of anatomical sciences: A blended learning approach.

Science.gov (United States)

Khalil, Mohammed K; Abdel Meguid, Eiman M; Elkhider, Ihsan A

2018-04-01

Blended learning is the integration of different learning approaches, new technologies, and activities that combine traditional face-to-face teaching methods with authentic online methodologies. Although advances in educational technology have helped to expand the selection of different pedagogies, the teaching of anatomical sciences has been challenged by implementation difficulties and other limitations. These challenges are reported to include lack of time, costs, and lack of qualified teachers. Easy access to online information and advances in technology make it possible to resolve these limitations by adopting blended learning approaches. Blended learning strategies have been shown to improve students' academic performance, motivation, attitude, and satisfaction, and to provide convenient and flexible learning. Implementation of blended learning strategies has also proved cost effective. This article provides a theoretical foundation for blended learning and proposes a validated framework for the design of blended learning activities in the teaching and learning of anatomical sciences. Clin. Anat. 31:323-329, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Polymer blends of polylactic acid (PLA) and polybutylene succinate-adipate

Science.gov (United States)

Ma, Wenguang

A series of blends consisting of polylactic acid (PLA) and aliphatic succinate polyester (BionolleRTM #3000) had been prepared and investigated. The results of mechanical property investigations showed that using 20 wt% Bionolle#3000 can significantly increase the toughness of PLA. BionolleRTM #3000 also reduces the physical aging rate of PLA so blends remain tough longer. Conversely, the stiffness of BionolleRTM #3000 can be significantly increased by blending in PLA. DMA and DSC results show that PLA/BionolleRTM 3000 blends are not thermodynamically miscible, but are compatible blends. Studies have also been performed to determine the amount and rate of aerobic biodegradation of PLA/aliphatic succinate polyester blends in biologically active composting, enzymatic, and soil environments. The changes in molecular weight, molecular structure and thermal properties in the composting environment were also studied by GPC, NMR and DSC analyses. The research results showed BionolleRTM #3000 had a high degradation rate, while PLA had a low degradation rate. PLA/BionolleRTM #3000 blends had moderate degradation rates that increased with BionolleRTM #3000 content. The melt flow behavior of PLA/BionolleRTM #3000 blends has been studied by capillary rheometry. The relationship of the blends' viscosity with their composition, shear stress, shear rate, and temperature has been investigated. Power law index and activation energy of PLA, BionolleRTM #3000 and their blends have been calculated. The experimental and theoretical data can let us understand the processability of PLA/BionolleRTM #3000 blends. A scanning electron microscope (SEM) was used to investigate the morphological structure of the PLA/BionolleRTM #3000 blends. Micrographs of the samples made from different methods (blown film, extrudate and compression molding sheet) were taken; their differences in morphology were compared. For comparison, the micrographs of blend PLA/BionolleRTM #6000 was also studied. The

Finding a balance in dimensions of blended learning

NARCIS (Netherlands)

Verkroost, M.; Meijerink, L.; Lintsen, H.W.; Veen, W.

2008-01-01

This article is a formative evaluation of a course in which a blended learning environment was created and a good balance in dimensions of blended learning was sought. Blended learning is defined as the total mix of pedagogical methods, using a combination of different learning strategies, both with

NOx emissions and combustibility characteristics of coal blends

Energy Technology Data Exchange (ETDEWEB)

Rubiera, F.; Arenillas, A.; Arias, B.; Pis, J.J. [CSIC, Instituto Nacional del Carbon, Oviedo (Spain). Dept. of Energy and Environment

2001-07-01

In this work, a series of coals with different origin and rank were blended and several aspects of the resultant blends were studied. This included determination of the grindability of individual coals and blends by means of the Hardgrove Grindability Index (HGI), and temperature programmed combustion test, which were carried out in a thermogravimetric analyser (TG) coupled to a quadruple mass spectrometer (MS) for evolved gas analysis. Special attention was paid to the combustibility parameters and the NO emissions during blends combustion. It was found that while some coal blends present interaction between the individual coals, others do not. This behaviour was assumed to be due to the differences in coal structure and functional groups composition. 18 refs., 11 figs., 2 tabs.

On The compatibility and dynamic vulcanization of Pom/Nbr blends

International Nuclear Information System (INIS)

Mortezaee, M.; Naveed Family, M.H.; Mehrabzadeh, M.

2001-01-01

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

20 CFR 418.3610 - Is there administrative or judicial review for administrative actions that are not initial...

Science.gov (United States)

2010-04-01

... Administrative Review Process § 418.3610 Is there administrative or judicial review for administrative actions... reviewed by us, but they are not subject to the administrative or judicial review process as provided by... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Is there administrative or judicial review...

Patterns and Meanings of English Words through Word Formation Processes of Acronyms, Clipping, Compound and Blending Found in Internet-Based Media

Directory of Open Access Journals (Sweden)

Rio Rini Diah Moehkardi

2017-02-01

Full Text Available This research aims to explore the word-formation process in English new words found in the internet-based media through acronym, compound,  clipping and blending and their meanings. This study applies Plag’s (2002 framework of acronym and compound; Jamet’s (2009 framework of clipping, and Algeo’s framework (1977 in Hosseinzadeh  (2014 for blending. Despite the  formula established in each respective framework,  there could be occurrences  of novelty and modification on how words are formed and  how meaning developed in  the newly formed words. The research shows that well accepted acronyms can become real words by taking lower case and affixation. Some acronyms initialized non-lexical words, used non initial letters, and used letters and numbers that pronounced the same with the words they represent. Compounding also includes numbers as the element member of the compound. The nominal nouns are likely to have metaphorical and idiomatic meanings. Some compounds evolve to new and more specific meaning. The study also finds that back-clipping is the most dominant clipping. In blending, the sub-category clipping of blending, the study finds out that when clipping takes place, the non-head element is back-clipped and the head is fore-clipped.

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.

Evaluation of the ignition behaviour of coals and blends

Energy Technology Data Exchange (ETDEWEB)

J. Faundez; F. Rubiera; X. Garcia; A. Arenillas; A.L. Gordon; J.J. Pis [CSIC, Instituto Nacional del Carbon, Oviedo (Spain). Department of Energy and Environment

2003-07-01

An experimental study about ignition of coals and blends was carried out by using an entrained flow reactor (EFR) with continuous feed. Seven coals of varying rank, from subbituminous to semianthracite, were tested and evolving gases (O{sub 2}, CO, CO{sub 2}, NO) were measured. The ignition temperature was evaluated from the evolution profiles of these gases, and correlated inversely to the reactivity of coals, as reflected by increasing values of ignition temperatures in the sequence subbituminous, high volatile bituminous, low volatile bituminous and semianthracite coals. Mechanism of ignition varied from an heterogeneous mechanism (for subbituminous, low volatile bituminous and semianthracite coals) to an homogeneous mechanism (for high volatile bituminous coal). Experiments with coal blends showed that if a low volatile bituminous coal is blended with a high volatile bituminous coal, the latter determines the value of the ignition temperature and ignition mechanism of the blend, when its percentage in the blend is 50% or higher. For blends of subbituminous and high volatile bituminous coals, the ignition mechanism of the blend is determined by the ignition mechanism of the coal with a higher content in the blend. 12 refs., 9 figs., 1 tab.

Design of Sustainable Blended Products using an Integrated Methodology

DEFF Research Database (Denmark)

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

2013-01-01

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....

Dual Energy Computed Tomography to Evaluate Hepatocellular Carcinoma Treated with Transcatheter Arterial Chemo-Embolization: Comparison between the Linear Blending and Nonlinear Moidal Blending Methods

International Nuclear Information System (INIS)

Shin, Sang Soo; Kim, Hyeong Wook; Lee, Daun; Kang, Heoung Keun; Kim, Jin Woong; Heo, Suk Hee; Jeong, Yong Yeon; Seon, Hyun Ju

2012-01-01

To compare the linear blending image with the nonlinear moidal blending image using dual energy CT for the evaluation of the viable portion of hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE). One-hundred and twenty three HCC patients incompletely treated after TACE were enrolled in this study. The dual energy mode (80 kVp and Sn140 kVp) was only applied in the late arterial phase scanning. A paired t-test was used to compare the lesion-to-liver contrast-to-noise ratio (CNR) and the image noise between the two blending images. Lesion conspicuity, image sharpness, image noise and the overall image quality between the two blending images were compared using the Wilcoxon matched-pair signed-ranks test. The lesion-to-liver CNR was significantly higher on the moidal blending image (5.6 ± 3.2) than on the linear blending image (2.7 ± 1.6) (p < 0.001). The image noise was significantly lower on the moidal blending image (10.9 ± 3.5) than on the linear blending image (17.5 ± 5.5) (p < 0.001). The lesion conspicuity and overall image quality were significantly better on the moidal blending image for both reviewers (p < 0.001). However, with respect to image sharpness, the linear blending image was significantly better for both reviewers (p < 0.01). The nonlinear moidal blending image of dual energy CT showed an increased lesion-to-liver CNR, decreased noise and improved overall image quality for the evaluation of the viable portion of HCC after TACE.

In-line Raman spectroscopic monitoring and feedback control of a continuous twin-screw pharmaceutical powder blending and tableting process.

Science.gov (United States)

Nagy, Brigitta; Farkas, Attila; Gyürkés, Martin; Komaromy-Hiller, Szofia; Démuth, Balázs; Szabó, Bence; Nusser, Dávid; Borbás, Enikő; Marosi, György; Nagy, Zsombor Kristóf

2017-09-15

The integration of Process Analytical Technology (PAT) initiative into the continuous production of pharmaceuticals is indispensable for reliable production. The present paper reports the implementation of in-line Raman spectroscopy in a continuous blending and tableting process of a three-component model pharmaceutical system, containing caffeine as model active pharmaceutical ingredient (API), glucose as model excipient and magnesium stearate as lubricant. The real-time analysis of API content, blend homogeneity, and tablet content uniformity was performed using a Partial Least Squares (PLS) quantitative method. The in-line Raman spectroscopic monitoring showed that the continuous blender was capable of producing blends with high homogeneity, and technological malfunctions can be detected by the proposed PAT method. The Raman spectroscopy-based feedback control of the API feeder was also established, creating a 'Process Analytically Controlled Technology' (PACT), which guarantees the required API content in the produced blend. This is, to the best of the authors' knowledge, the first ever application of Raman-spectroscopy in continuous blending and the first Raman-based feedback control in the formulation technology of solid pharmaceuticals. Copyright © 2017 Elsevier B.V. All rights reserved.

Consequences of Switching to Blended Learning: The Grenoble Medical School Key Elements.

Science.gov (United States)

Houssein, Sahal; Di Marco, Lionel; Schwebel, Carole; Luengo, Vanda; Morand, Patrice; Gillois, Pierre

2018-01-01

In 2006, the Grenoble-Alpes University Medical School decided to switch the learning paradigm of the first year to a blended learning model based on a flipped classroom with a continuous dual assessment system providing personal follow-up. We report a descriptive analysis of two pedagogical models. The innovative blended learning model is divided into 5 week-sequences of learning, starting with a series of knowledge capsules, following with Interactive On Line Questions, Interactive On Site Training and an Explanation Meeting. The fourth and final steps are the dual assessment system that prepares for the final contest and the personal weekly follow-up. The data were extracted from the information systems over 17 years, during which the same learning model was applied. With the same student workload, the hourly knowledge/skills ratio decreased to approximately 50% with the blended learning model. The teachers' workload increased significantly in the first year (+70%), and then decreased each year (reaching -20%). Furthermore, the type of education has also changed for the teacher, from an initial hourly knowledge/skill ratio of 3, to a ratio of 1/3 with the new model after a few years. The institution also needed to resize the classroom from a large amphitheatre to small interactive learning spaces. There is a significant initial effort required to establish this model both for the teachers and for the institution, which have different needs and costs However, the satisfaction rates and the demand for extension to the other curriculums from medics and paramedics learners indicate that this model provides the enhanced learning paradigm of the future.

Preparation of LDPE/LNR Blend Via Emulsion Dispersion

International Nuclear Information System (INIS)

Rusli Daik; Yee Lee Ching

2007-01-01

Low density polyethylene (LDPE)/ liquid natural rubber (LNR) blends with the composition of 100LDPE/ 0LNR, 70LDPE/ 30LNR, 60LDPE/ 40LNR and 40LDPE/ 60LNR were prepared via dispersion of LDPE and LNR emulsion. LNR was obtained via photochemical sensitization of natural rubber (NR). Emulsion of LNR was prepared by using sodium dodecyl sulfate (SDS) and 1-hexanol as the emulsifier and co- emulsifier respectively. Emulsion of LDPE was prepared in the same way by using LDPE solution in carbon tetrachloride, SDS and 1-hexanol. LDPE/ LNR blends were prepared via mixing of LNR and LDPE emulsions. Mechanical properties of the blends were analyzed by tensile, hardness and impact test. Optimum mechanical properties were observed for composite with composition of 60LDPE/ 40LNR that showed the maximum value of stress and strain. The glass transition temperature, T g , of the blends as obtained from differential scanning calorimetric (DSC) showed that the blends were homogeneous. Morphology study by using scanning electron microscopy (SEM) also indicates the homogeneity of LDPE/ LNR blends produced. (author)

Preparation and Characterization of Keratin/Alginate Blend Microparticles

Directory of Open Access Journals (Sweden)

Yaowalak Srisuwan

2018-01-01

Full Text Available The water-in-oil (W/O emulsification-diffusion method was used for construction of keratin (Ker, alginate (Alg, and Ker/Alg blend microparticles. The Ker, Alg, and Ker/Alg blend solutions were used as the water phase, while ethyl acetate was used as the oil phase. Firstly, different concentrations of Ker solution was used to find suitable content. 1.6% w/v Ker solution was blended with the same concentration of the Alg solution for further microparticle construction. Results from scanning electron microscope analysis show that the microparticles have different shapes: spherical, bowl-like, porous, and hollow, with several sizes depending on the blend ratio. FTIR and TG analyses indicated that the secondary structure and thermal stability of the microparticles were influenced by the Ker/Alg blend ratio. The interaction between functional groups of keratin and alginate was the main factor for both β-sheet structure and Td,max values of the microparticles. The results suggested that Ker/Alg blend microparticles might be applied in many fields by varying the Ker/Alg ratio.

Dipeptide-based polyphosphazene and polyester blends for bone tissue engineering.

Science.gov (United States)

Deng, Meng; Nair, Lakshmi S; Nukavarapu, Syam P; Jiang, Tao; Kanner, William A; Li, Xudong; Kumbar, Sangamesh G; Weikel, Arlin L; Krogman, Nicholas R; Allcock, Harry R; Laurencin, Cato T

2010-06-01

Polyphosphazene-polyester blends are attractive materials for bone tissue engineering applications due to their controllable degradation pattern with non-toxic and neutral pH degradation products. In our ongoing quest for an ideal completely miscible polyphosphazene-polyester blend system, we report synthesis and characterization of a mixed-substituent biodegradable polyphosphazene poly[(glycine ethyl glycinato)(1)(phenyl phenoxy)(1)phosphazene] (PNGEG/PhPh) and its blends with a polyester. Two dipeptide-based blends namely 25:75 (Matrix1) and 50:50 (Matrix2) were produced at two different weight ratios of PNGEG/PhPh to poly(lactic acid-glycolic acid) (PLAGA). Blend miscibility was confirmed by differential scanning calorimetry, Fourier transform infrared spectroscopy, and scanning electron microscopy. Both blends resulted in higher tensile modulus and strength than the polyester. The blends showed a degradation rate in the order of Matrix2PLAGA in phosphate buffered saline at 37 degrees C over 12 weeks. Significantly higher pH values of degradation media were observed for blends compared to PLAGA confirming the neutralization of PLAGA acidic degradation by polyphosphazene hydrolysis products. The blend components PLAGA and polyphosphazene exhibited a similar degradation pattern as characterized by the molecular weight loss. Furthermore, blends demonstrated significantly higher osteoblast growth rates compared to PLAGA while maintaining osteoblast phenotype over a 21-day culture. Both blends demonstrated improved biocompatibility in a rat subcutaneous implantation model compared to PLAGA over 12 weeks. (c) 2010 Elsevier Ltd. All rights reserved.

Blended Learning Opportunities in Ukrainian IT Public Education

Science.gov (United States)

Szimkovics, Tamás

2017-01-01

Based on previous surveys the usage of ICT and blended learning is at a low level in Ukraine. To catch up with the European average, it is important to familiarize the students and teachers with blended learning in the secondary school. The information technology classes provide the best opportunity to introduce the blended learning, because they…

Multiscattering illumination in blended acquisition design

NARCIS (Netherlands)

Berkhout, A.J.; Blacquière, G.; Verschuur, D.J.

2010-01-01

In traditional seismic surveys the firing time between shots is such that the records do not interfere in time. However, in the concept of blending the records do overlap, allowing much denser and wider geometries in an economic way. The blending parameters are the locations of the involved sources

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…

Blended Learning in Action: A Practical Guide toward Sustainable Change

Science.gov (United States)

Tucker, Catlin R.; Wycoff, Tiffany; Green, Jason T.

2017-01-01

Blended learning has the power to reinvent education, but transitioning to a blended model is challenging. Blended learning requires a fundamentally new approach to learning as well as a new skillset for both teachers and school leaders. Loaded with research, examples, and resources, "Blended Learning in Action" demonstrates the…

A drop penetration method to measure powder blend wettability.

Science.gov (United States)

Wang, Yifan; Liu, Zhanjie; Muzzio, Fernando; Drazer, German; Callegari, Gerardo

2018-03-01

Water wettability of pharmaceutical blends affects important quality attributes of final products. We investigate the wetting properties of a pharmaceutical blend lubricated with Magnesium Stearate (MgSt) as a function of the mechanical shear strain applied to the blend. We measure the penetration dynamics of sessile drops deposited on slightly compressed powder beds. We consider a blend composed of 9% Acetaminophen 90% Lactose and 1% MgSt by weight. Comparing the penetration time of water and a reference liquid Polydimethylsiloxane (silicon oil) we obtain an effective cosine of the contact angle with water, based on a recently developed drop penetration method. We repeat the experiments for blends exposed to increasing levels of shear strain and demonstrate a significant decrease in water wettability (decrease in the cosine of the contact angle). The results are consistent with the development of a hydrophobic film coating the powder particles as a result of the increased shear strain. Finally, we show that, as expected dissolution times increase with the level of shear strain. Therefore, the proposed drop penetration method could be used to directly assess the state of lubrication of a pharmaceutical blend and act as a quality control on powder blend attributes before the blend is tableted. Copyright © 2017 Elsevier B.V. All rights reserved.

Non-isothermal crystallization of PET/PLA blends

International Nuclear Information System (INIS)

Chen, Huipeng; Pyda, Marek; Cebe, Peggy

2009-01-01

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.

Chitosan-Based Polymer Blends: Current Status and applications

International Nuclear Information System (INIS)

Hefian, E.A.E.; Nasef, M.M.

2014-01-01

This paper reviews the latest developments in chitosan-based blends and their potential applications in various fields. Various blends together with other derivatives, such as composites and graft copolymers, have been developed to overcome chitosans disadvantages, including poor mechanical properties and to improve its functionality towards specific applications. The progress made in blending chitosan with synthetic and natural polymers is presented. The versatility and unique characteristics, such as hydrophilicity, film-forming ability, biodegradability, biocompatibility, antibacterial activity and non-toxicity of chitosan has contributed to the successful development of various blends for medical, pharmaceutical, agricultural and environmental applications. (author)

TANK 21 AND TANK 24 BLEND AND FEED STUDY: BLENDING TIMES, SETTLING TIMES, AND TRANSFERS

Energy Technology Data Exchange (ETDEWEB)

Lee, S.; Leishear, R.; Poirier, M.

2012-05-31

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 (<1200 mg/l). (4) Experimental tests with sludge batch 6 simulant and field turbidity data from a recent Tank 21 mixing evolution suggest the solid

Shape memory behaviour of radiation-crosslinked PCL/PMVS blends

International Nuclear Information System (INIS)

Zhu Guangming; Xu Shuogui; Wang Jinhua; Zhang Longbin

2006-01-01

The performance and radiation crosslinking of polycaprolactone (PCL) and polymethylvinylsiloxane (PMVS) blends has been investigated. Radiation crosslinking of PCL/PMVS blends followed the Charlesby-Pinner equation, and PMVS promoted the radiation crosslinking of the blends. As the concentration of PMVS increased, the gelation dose and the ratio of degradation to crosslinking (p 0 /q 0 ) decreased and the efficiency of radiation crosslinking increased. The elastic modulus below the melting point of PCL of radiation-crosslinked PCL/PMVS blends decreased with the increase of PMVS, and increased above the melting point. The crosslinked PCL/PMVS blends exhibited excellent shape memory effects, and the ratios of deformation to recovery were more than 95%

Method to blend separator powders

Science.gov (United States)

Guidotti, Ronald A.; Andazola, Arthur H.; Reinhardt, Frederick W.

2007-12-04

A method for making a blended powder mixture, whereby two or more powders are mixed in a container with a liquid selected from nitrogen or short-chain alcohols, where at least one of the powders has an angle of repose greater than approximately 50 degrees. The method is useful in preparing blended powders of Li halides and MgO for use in the preparation of thermal battery separators.

Study of PP/Polybutene Blends Modified by Gamma Irradiation and HMS-PP/Polybutene Blends

International Nuclear Information System (INIS)

Lugao, A. B.

2006-01-01

The polypropylene (PP) has been applied to a wide range of production due to its various excellent properties such as cheapness, high stiffness, chemical resistance, no environmental pollution when incinerated, low specific density and good mechanical properties. However, PP is a linear polymer which exhibits low melt strength. One of the effective approaches to achieve high melt strength (HMS) is to add chain branches onto backbone polymers. High melt strength polypropylene (HMS-PP) has been recently developed and introduced in the market by the major international polypropylene producers. As a consequence different methods have been applied to modify polypropylenes by chain branches. The technology obtained by IPEN together with EMBRARAD and BRASKEM comprises chain branches added onto backbone species using gamma radiation, which is generated from a Co 6 0 source. Such radiation is very convenient in order to improve polymer materials by grafting, crosslinking and degradation. Another important approach to the development of polymer materials is based on the combination of different polymers into a new product having some of the desired properties of each component. In this work, gamma irradiation technique was used to induce chemical changes in commercial polypropylene (HMS-PP) that was after blended with polybutene and in polypropylene/polybutene blends. The samples were irradiated with a 60 C o source at doses of 12,5 and 20kGy in the presence of acetylene. It was investigated how the two different routes of blends processing can modify their properties. Indeed the results from melt flow, gel fraction and rheology reveal the influence of the process route in the blends properties. Effects on the elongation at break and break strength were observed by the results of mechanical tests. The results from rheology demonstrated an increase in melt strength and drawability of the blends

Blended learning in health education: three case studies.

Science.gov (United States)

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

2014-09-01

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 active and collaborative? Three cases of blended, active and collaborative learning are presented. In case 1 a virtual classroom is used to realize online problem-based learning (PBL). In case 2 PBL cases are presented in Second Life, a 3D immersive virtual world. In case 3 discussion forums, blogs and wikis were used. In all cases face-to-face meetings were also organized. Evaluation results of the three cases clearly show that active, collaborative learning at a distance is possible. Blended learning enables the use of novel instructional methods and student-centred education. The three cases employ different educational methods, thus illustrating diverse possibilities and a variety of learning activities in blended learning. Interaction and communication rules, the role of the teacher, careful selection of collaboration tools and technical preparation should be considered when designing and implementing blended learning.

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...

SAVANNAH RIVER SITE INCIPIENT SLUDGE MIXING IN RADIOACTIVE LIQUID WASTE STORAGE TANKS DURING SALT SOLUTION BLENDING

Energy Technology Data Exchange (ETDEWEB)

Leishear, R.; Poirier, M.; Lee, S.; Steeper, T.; Fowley, M.; Parkinson, K.

2011-01-12

This paper is the second in a series of four publications to document ongoing pilot scale testing and computational fluid dynamics (CFD) modeling of mixing processes in 85 foot diameter, 1.3 million gallon, radioactive liquid waste, storage tanks at Savannah River Site (SRS). Homogeneous blending of salt solutions is required in waste tanks. Settled solids (i.e., sludge) are required to remain undisturbed on the bottom of waste tanks during blending. Suspension of sludge during blending may potentially release radiolytically generated hydrogen trapped in the sludge, which is a safety concern. The first paper (Leishear, et. al. [1]) presented pilot scale blending experiments of miscible fluids to provide initial design requirements for a full scale blending pump. Scaling techniques for an 8 foot diameter pilot scale tank were also justified in that work. This second paper describes the overall reasons to perform tests, and documents pilot scale experiments performed to investigate disturbance of sludge, using non-radioactive sludge simulants. A third paper will document pilot scale CFD modeling for comparison to experimental pilot scale test results for both blending tests and sludge disturbance tests. That paper will also describe full scale CFD results. The final paper will document additional blending test results for stratified layers in salt solutions, scale up techniques, final full scale pump design recommendations, and operational recommendations. Specifically, this paper documents a series of pilot scale tests, where sludge simulant disturbance due to a blending pump or transfer pump are investigated. A principle design requirement for a blending pump is UoD, where Uo is the pump discharge nozzle velocity, and D is the nozzle diameter. Pilot scale test results showed that sludge was undisturbed below UoD = 0.47 ft{sup 2}/s, and that below UoD = 0.58 ft{sup 2}/s minimal sludge disturbance was observed. If sludge is minimally disturbed, hydrogen will not be

Modification of polymer blends by irradiation

International Nuclear Information System (INIS)

Zuchowska, D.; Zagorski, Z.P.

1999-01-01

Modification of polymers, especially of polyolefin-elastomer blends (e. g. ethylene/propylene/diene terpolymer, ethylene propylene copolymer, ethylene/vinyl acetate copolymer etc.), by irradiation with a beam of fast electrons is discussed. Irradiation of polymer blends usually results in enhanced interactions between the constituents, caused among other things, by grafting induced at the polymer interphase. As a result, mechanical properties are affected to an extent depending on the proportion and type of constituent polymers, stabilizer content and radiation dose. Breaking strength (σ) relative elongation at break (ε) and melt flow rate (MFR), were examined for a triblock styrene/butadiene/styrene (SBS) copolymer, polypropylene (PP), and a PP-SBS blend (50:50 by wt.). In PP, the content of the crystal phase was determined. Irradiation was found to make SBS crosslink, as a result, σ rose by 25% and ε remained unaffected. PP was found to become degraded upon irradiation (MFR rose as much as 16 times), thereby σ and ε decreased considerably. In pure PP, the content of the crystal phase was found to increase. The variations of σ and ε in the irradiated PP-SBS blend follow a tendency similar to that in the SBS copolymer examined. This fact suggests the SBS copolymer to have a decisive effect on the macroscopic properties of the PP-SBS blend. (author)

Beeswax-Colophony Blend: A Novel Green Organic Coating for Protection of Steel Drinking Water Storage Tanks

Directory of Open Access Journals (Sweden)

Sara Abdikheibari

2015-09-01

Full Text Available Beeswax-colophony blend is mainly used as a sealant mixture for preservation applications. The beeswax itself, however, has had a long way in history taking part in conservation processes including mummification. In this research, this blend was used as a protective coating for drinking water distribution tanks. Initially, a layer with 400 μm thickness was applied on a sand blasted mild steel plate. The long-term electrochemical behavior of the coating was investigated by open circuit potential (OCP and electrochemical microbiological characteristics of the coating, microbial and chemical examinations were performed on drinking water samples that had been in contact with the coating. Furthermore, its behavior in an up-flow anaerobic sludge blanket reactor (UASBR in a wastewater treatment plant was investigated using the scanning electron microscopy (SEM technique. Regarding the consistency of experimental results, it was concluded that this proposed recyclable blend could be considered as a novel green organic coating and also a good corrosion barrier even in aggressive environments.

Effect of Gamma Radiation on the Chemical and Physical Properties of Plasticised Carboxymethyl Cellulose (Cc) / Poly (vinyl alcohol)(Pva) Polymer Blend

International Nuclear Information System (INIS)

El-Salmawi, M.K.; Abu Zaid, M.M.; Ibraheim, M.S.; El-Nagger Abdel Wahab, M.; Zahran Abdel Hamid, H.

2000-01-01

The chemical and physical properties of plasticizer carboxymethyl cellulose (CMC)/ poly (vinylalcohol)(PVA) polymer blend before and after exposure to gamma ray were investigated by means of mechanical properties, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscope (SEM). It was found that addition of plasticizer causes a significant increase in elongation at break and causes a marked drop in thermal stability. Thus, the addition of glycerol cause a significant decrease in glass transition temperature(Tg) of about 24 degree from the initial value. The morphological structure of plasticised blend was investigated by observation of fracture surfaces using SEM. The plasticised blend was used for recovery of some heavy metals from their salts such as Cu(II), Co(II) and Ni(II). It was found that plasticised blend have a great ability for absorbing these metals and it is measured by compleximetric titration and colour strength measurements

A blending rule for octane numbers of PRFs and TPRFs with ethanol

KAUST Repository

AlRamadan, Abdullah S.; Sarathy, Mani; Khurshid, Muneeb; Badra, Jihad

2016-01-01

-gasoline synergistic/antagonistic blending effects. Understanding ethanol blending effects with simpler gasoline surrogates blends may enable a better understanding of ethanol blending with complex multi-component gasoline fuels. This study presents a blending rule

Teaching Parametric Urban Design in a Blended Learning Format

DEFF Research Database (Denmark)

Steinø, Nicolai

2015-01-01

On the basis of a theoretical discussion of the concept of blended learning, this paper presents the pre- paration, execution and evaluation of a 5 ECTS blended learning course on parametric urban design for a group of some 50 BSc students of architecture and design at Aalborg university...... and curriculum develop- ment, and di culties to nd time for research. Despite the general consensus that developing online/blended learning courses requires both technical support, complex software installations, and substantial preparation time, it is shown that free web ser- vices and low-tech adaptations...... of traditional teaching assets are su cient to get started with blended learning with only little extra e ort. While the pilot blended learning course which provided the insights for this paper has room for impro- vement, it represents a decent rst shot at developing blended learning courses for higher education...

Optimization of the octane response of gasoline/ethanol blends

KAUST Repository

Badra, Jihad; AlRamadan, Abdullah S.; Sarathy, Mani

2017-01-01

The octane responses of gasoline/ethanol mixtures are not well understood because of the unidentified intermolecular interactions in such blends. In general, when ethanol is blended with gasoline, the Research Octane Number (RON) and the Motor Octane Number (MON) non-linearly increase or decrease, and the non-linearity is determined by the composition of the base gasoline and the amount of added ethanol. The complexity of commercial gasolines, comprising of hundreds of different components, makes it challenging to understand ethanol-gasoline synergistic/antagonistic blending effects. Understanding ethanol blending effects with simpler gasoline surrogates is critical to acquire knowledge about ethanol blending with complex multi-component gasoline fuels. In this study, the octane numbers (ON) of ethanol blends with five relevant gasoline surrogate molecules were measured. The molecules investigated in this study include: n-pentane, iso-pentane, 1,2,4-trimethylbenzene, cyclopentane and 1-hexene. These new measurements along with the available data of n-heptane, iso-octane, toluene, various primary reference fuels (PRF) and toluene primary reference fuels (TPRF) with ethanol are used to develop a blending rule for the octane response (RON and MON) of multi-component blends with ethanol. In addition, new ON data are collected for six Fuels for Advanced Combustion Engine (FACE) with ethanol. The relatively simple volume based model successfully predicts the octane numbers (ON) of the various ethanol/PRF and ethanol/TPRF blends with the majority of predictions being within the ASTM D2699 (RON) and D2700 (MON) reproducibility limits. The model is also successfully validated against the ON of the FACE gasolines blended with ethanol with the majority of predictions being within the reproducibility limits. Finally, insights into the possible causes of the synergistic and antagonistic effects of different molecules with ethanol are provided.

Optimization of the octane response of gasoline/ethanol blends

KAUST Repository

Badra, Jihad

2017-07-04

The octane responses of gasoline/ethanol mixtures are not well understood because of the unidentified intermolecular interactions in such blends. In general, when ethanol is blended with gasoline, the Research Octane Number (RON) and the Motor Octane Number (MON) non-linearly increase or decrease, and the non-linearity is determined by the composition of the base gasoline and the amount of added ethanol. The complexity of commercial gasolines, comprising of hundreds of different components, makes it challenging to understand ethanol-gasoline synergistic/antagonistic blending effects. Understanding ethanol blending effects with simpler gasoline surrogates is critical to acquire knowledge about ethanol blending with complex multi-component gasoline fuels. In this study, the octane numbers (ON) of ethanol blends with five relevant gasoline surrogate molecules were measured. The molecules investigated in this study include: n-pentane, iso-pentane, 1,2,4-trimethylbenzene, cyclopentane and 1-hexene. These new measurements along with the available data of n-heptane, iso-octane, toluene, various primary reference fuels (PRF) and toluene primary reference fuels (TPRF) with ethanol are used to develop a blending rule for the octane response (RON and MON) of multi-component blends with ethanol. In addition, new ON data are collected for six Fuels for Advanced Combustion Engine (FACE) with ethanol. The relatively simple volume based model successfully predicts the octane numbers (ON) of the various ethanol/PRF and ethanol/TPRF blends with the majority of predictions being within the ASTM D2699 (RON) and D2700 (MON) reproducibility limits. The model is also successfully validated against the ON of the FACE gasolines blended with ethanol with the majority of predictions being within the reproducibility limits. Finally, insights into the possible causes of the synergistic and antagonistic effects of different molecules with ethanol are provided.

Evaluation of fuel properties for microalgae Spirulina platensis bio-diesel and its blends with Egyptian petro-diesel

Directory of Open Access Journals (Sweden)

Soha S.M. Mostafa

2017-05-01

In this study, the feasibility of biodiesel production from microalga Spirulina platensis has been investigated. The physico–chemical characteristics of the produced biodiesel were studied according to the standards methods of analysis (ASTM and evaluated according to their fuel properties as compared to Egyptian petro-diesel. Blends of microalgae biodiesel and petro-diesel (B2, B5, B10 and B20 were prepared on a volume basis and their physico–chemical characteristics have been also studied. The obtained results showed that; with the increase of biodiesel concentration in the blends; the viscosity, density, total acid number, initial boiling point, calorific value, flash point, cetane number and diesel index increase. While the pour point, cloud point, carbon residue and sulfur, ash and water contents decrease. The observed properties of the blends were within the recommended petro-diesel standard specifications and they are in favor of better engine performance.

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.

Effects of Dietary Zinc Oxide and a Blend of Organic Acids on Broiler Live Performance, Carcass Traits, and Serum Parameters

Directory of Open Access Journals (Sweden)

BG Sarvari

2015-12-01

Full Text Available ABSTRACT This experiment was carried out to evaluate the effect of different dietary supplementation levels of zinc oxide and of an organic acid blend on broiler performance, carcass traits, and serum parameters. A total of 2400 one-day-old male Ross 308 broiler chicks, with average initial body weight 44.21±0.19g, was distributed according to a completely randomized design in a 2 x 3 factorial arrangement. Six treatments, consisting of diets containing two zinc oxide levels (0 and 0.01% of the diet and three organic acid blend levels (0, 0.15, and 0.30% were applied, with eight replicates of 50 birds each. The experimental diets were supplied ad libitum for 42 days. There were significant performance differences among birds fed the different zinc oxide and organic acid blend levels until 42 d of age (p<0.01. The result of this experiment showed that the organic acid blend did not affect feed intake, but zinc oxide increased feed intake. Carcass traits were not influenced by the experimental supplements. Zinc oxide supplementation increased serum alkaline phosphatase level (p<0.01. The organic acid blend reduced serum cholesterol and triglyceride levels (p<0.05. No interactions were found between zinc oxide and the organic acid blend for none of the evaluated parameters. We concluded that zinc oxide and the evaluated organic acid blend improve broiler performance.

Effects of catalysts on combustion characteristics and kinetics of coal-char blends

Science.gov (United States)

Hu, Yingjie; Wang, Zhiqiang; Cheng, Xingxing; Liu, Ming; Ma, Chunyuan

2018-04-01

The effects of Fe2O3, CaO, and MnO2 on the combustion characteristics and kinetics of coal-char blends were investigated using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results indicated that catalysts exhibited positive effects on the combustion characteristics of coal-char blends, especially in the initial period of coal-char blends combustion. With catalysts addition (mass 1.5%), it could improves volatile matter release, and reduces ignition point, promotes char to begin burning under lower temperature. The ignition index (C) was increased, respectively, by 27% for Fe2O3, 6% for CaO, 11.3% for MnO2, and the combustion characteristic index ( S ) was increased respectively, by 29% for Fe2O3, 5% for CaO, 8.3% for MnO2. In addition, two kinetic models (R2 and F1) were adopted to calculate the kinetic parameters in different stage of combustion processes. The results showed that with Fe2O3 or CaO addition, the activation energy at second stage decreases from 86.0 KJ/mol to 76.92 KJ/mol and 75.12 KJ/mol, respectively. There are no obvious decreases at the third stage of samples combustion process.

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.

Photonic polymer-blend structures and method for making

Science.gov (United States)

Barnes, Michael D.

2004-06-29

The present invention comprises the formation of photonic polymer-blend structures having tunable optical and mechanical properties. The photonic polymer-blend structures comprise monomer units of spherical microparticles of a polymer-blend material wherein the spherical microparticles have surfaces partially merged with one another in a robust inter-particle bond having a tunable inter-particle separation or bond length sequentially attached in a desired and programmable architecture. The photonic polymer-blend structures of the present invention can be linked by several hundred individual particles sequentially linked to form complex three-dimensional structures or highly ordered two-dimensional arrays of 3D columns with 2D spacing.

Blending Study For SRR Salt Disposition Integration: Tank 50H Scale-Modeling And Computer-Modeling For Blending Pump Design, Phase 2

International Nuclear Information System (INIS)

Leishear, R.; Poirier, M.; Fowley, M.

2011-01-01

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 300,000-800,000 gallons of salt solution will be blended in 1.3 million gallon tanks and qualified for use as feedstock for SWPF. Blending requires the miscible salt solutions from potentially multiple source tanks per batch to be well mixed without disturbing settled sludge solids that may be present in a Blend Tank. Disturbing solids may be problematic both from a feed quality perspective as well as from a process safety perspective where hydrogen release from the sludge is a potential flammability concern. To develop the necessary technical basis for the design and operation of blending equipment, Savannah River National Laboratory (SRNL) completed scaled blending and transfer pump tests and computational fluid dynamics (CFD) modeling. A 94 inch diameter pilot-scale blending tank, including tank internals such as the blending pump, transfer pump, removable cooling coils, and center column, were used in this research. The test tank represents a 1/10.85 scaled version of an 85 foot diameter, Type IIIA, nuclear waste tank that may be typical of Blend Tanks used in SDI. Specifically, Tank 50 was selected as the tank to be modeled per the SRR, Project Engineering Manager. SRNL blending tests investigated various fixed position, non-rotating, dual nozzle pump designs, including a blending pump model provided by the blend pump vendor, Curtiss Wright (CW). Primary research goals were to assess blending times and to evaluate incipient sludge disturbance for waste tanks. Incipient sludge disturbance was defined by SRR and SRNL as minor blending of settled sludge from the tank bottom into suspension due to blending pump operation, where

BLENDING STUDY FOR SRR SALT DISPOSITION INTEGRATION: TANK 50H SCALE-MODELING AND COMPUTER-MODELING FOR BLENDING PUMP DESIGN, PHASE 2

Energy Technology Data Exchange (ETDEWEB)

Leishear, R.; Poirier, M.; Fowley, M.

2011-05-26

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 300,000-800,000 gallons of salt solution will be blended in 1.3 million gallon tanks and qualified for use as feedstock for SWPF. Blending requires the miscible salt solutions from potentially multiple source tanks per batch to be well mixed without disturbing settled sludge solids that may be present in a Blend Tank. Disturbing solids may be problematic both from a feed quality perspective as well as from a process safety perspective where hydrogen release from the sludge is a potential flammability concern. To develop the necessary technical basis for the design and operation of blending equipment, Savannah River National Laboratory (SRNL) completed scaled blending and transfer pump tests and computational fluid dynamics (CFD) modeling. A 94 inch diameter pilot-scale blending tank, including tank internals such as the blending pump, transfer pump, removable cooling coils, and center column, were used in this research. The test tank represents a 1/10.85 scaled version of an 85 foot diameter, Type IIIA, nuclear waste tank that may be typical of Blend Tanks used in SDI. Specifically, Tank 50 was selected as the tank to be modeled per the SRR, Project Engineering Manager. SRNL blending tests investigated various fixed position, non-rotating, dual nozzle pump designs, including a blending pump model provided by the blend pump vendor, Curtiss Wright (CW). Primary research goals were to assess blending times and to evaluate incipient sludge disturbance for waste tanks. Incipient sludge disturbance was defined by SRR and SRNL as minor blending of settled sludge from the tank bottom into suspension due to blending pump operation, where

Improving Curriculum through Blended Learning Pedagogy

Science.gov (United States)

Darojat, Ojat

2016-01-01

This paper is a study of blended learning pedagogy in open and distance learning (ODL), involving two universities in Southeast Asia, STOU Thailand and UT Indonesia. The purpose of this study is to understand the issues related to the implementation of blended-learning pedagogy. Qualitative case study was employed to optimize my understanding of…

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

Evaluation of Anti-Knock Quality of Dicyclopentadiene-Gasoline Blends

KAUST Repository

Al-Khodaier, Mohannad

2017-03-28

Increasing the anti-knock quality of gasoline fuels can enable higher efficiency in spark ignition engines. In this study, the blending anti-knock quality of dicyclopentadiene (DCPD), a by-product of ethylene production from naphtha cracking, with various gasoline fuels is explored. The blends were tested in an ignition quality tester (IQT) and a modified cooperative fuel research (CFR) engine operating under homogenous charge compression ignition (HCCI) and knock limited spark advance (KLSA) conditions. Due to current fuel regulations, ethanol is widely used as a gasoline blending component in many markets. In addition, ethanol is widely used as a fuel and literature verifying its performance. Moreover, because ethanol exhibits synergistic effects, the test results of DCPD-gasoline blends were compared to those of ethanol-gasoline blends. The experiments conducted in this work enabled the screening of DCPD auto-ignition characteristics across a range of combustion modes. The synergistic blending nature of DCPD was apparent and appeared to be greater than that of ethanol. The data presented suggests that DCPD has the potential to be a high octane blending component in gasoline; one which can substitute alkylates, isomerates, reformates, and oxygenates.

Evaluation of Anti-Knock Quality of Dicyclopentadiene-Gasoline Blends

KAUST Repository

Al-Khodaier, Mohannad; Bhavani Shankar, Vijai Shankar; Waqas, Muhammad; Naser, Nimal; Sarathy, Mani; Johansson, Bengt

2017-01-01

Increasing the anti-knock quality of gasoline fuels can enable higher efficiency in spark ignition engines. In this study, the blending anti-knock quality of dicyclopentadiene (DCPD), a by-product of ethylene production from naphtha cracking, with various gasoline fuels is explored. The blends were tested in an ignition quality tester (IQT) and a modified cooperative fuel research (CFR) engine operating under homogenous charge compression ignition (HCCI) and knock limited spark advance (KLSA) conditions. Due to current fuel regulations, ethanol is widely used as a gasoline blending component in many markets. In addition, ethanol is widely used as a fuel and literature verifying its performance. Moreover, because ethanol exhibits synergistic effects, the test results of DCPD-gasoline blends were compared to those of ethanol-gasoline blends. The experiments conducted in this work enabled the screening of DCPD auto-ignition characteristics across a range of combustion modes. The synergistic blending nature of DCPD was apparent and appeared to be greater than that of ethanol. The data presented suggests that DCPD has the potential to be a high octane blending component in gasoline; one which can substitute alkylates, isomerates, reformates, and oxygenates.

Manufacturing Initiative

Data.gov (United States)

National Aeronautics and Space Administration — The Advanced Manufacturing Technologies (AMT) Project supports multiple activities within the Administration's National Manufacturing Initiative. A key component of...

Development and initial evaluation of blended cognitive behavioural treatment for major depression in routine specialized mental health care

Directory of Open Access Journals (Sweden)

Lisa C. Kooistra

2016-05-01

Discussion: Although no conclusions can be drawn based on the current study, our observations suggest that a blended CBT approach might shorten treatment duration and has the potential to be a valuable treatment option for patients with severe depression in specialized mental health care settings. Further exploration of the effectiveness of our bCBT protocol by means of a randomized controlled trial is warranted.

An investigation on radiation crosslinked foam of LDPE/EVA blends

International Nuclear Information System (INIS)

Siqin Dalai; Chen Wenxiu

1995-01-01

LDPE/EVA blend, irradiated by γ-ray then expansed by heat as a foam material, the EVA content in LDPE/EVA blend was benefited to form gelation. The gel fraction on irradiated LDPE/EVA blend increased with the increasing of its EVA content in a given dose. The gel fraction values of LDPE/EVA blend with 30% EVA content were higher than those of other blends in a same given dose, its gel fraction value was 1.7 times as those values of LDPE without EVA. The gel fractions on LDPE/EVA blend were increased with dose in oxygen, in air and in nitrogen, the formation of gel was limited by oxygen. The oxidation products on foam of LDPE/EVA blend were observed in nitrogen, in air and in oxygen by FTIR spectra. The LDPE/EVA blend system has no protection effect from oxidation comparison with the LDPE system without EVA which has less oxidation product than those without EVA in a same given gel fraction. The gel fraction on foam of LDPE/EVA blend around 25-35%, dose 25 ± 5kGy, irradiated by γ-ray in air or in nitrogen, with higher expansion ratio (19), smaller cell diameter (0.175mm), lower apparent density (0.042g/cm 3 ), higher tensile strength (0.40MPa) and longer elongation at break (290-360%) on foam of LDPE/EVA blend were selected. It was opitimum condition for application in this systems. The relations among gel fraction on LDPE/EVA blend, expansion ratio, apparent density, average cell diameter and mechanical properties of foamed sheet were discussed. (author)

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......, the methodology is highlighted through two case studies involving gasoline blends and lubricant base oils....

Critical Success Factor for Implementing Vocational Blended Learning

Science.gov (United States)

Dewi, K. C.; Ciptayani, P. I.; Surjono, H. D.; Priyanto

2018-01-01

Blended learning provides many benefits to the flexibility of time, place and situation constraints. The research’s objectives was describing the factors that determine the successful implementation of blended learning in vocational higher education. The research used a qualitative approach, data collected through observations and interviews by questionnare based on the CSFs indicators refers to TAM and Kliger. Data analysis was inductive method. The result provided an illustration that the success of vocational blended learning implementation was largely determined by the selection of instructional models that are inline with learning achievement target. The effectiveness of blended learning required the existence of policy support, readiness of IT infrastructure. Changing lecturer’s culture by utilizing ICT can also encourage the accelerated process of successful implementation. It can concluded that determinant factor of successful implementation of blended learning in vocational education is determined by teacher’s ability in mastering the pedagogical knowledge of designing instructional models.

HEU to LEU conversion and blending facility: Oxide blending alternative to produce LEU oxide for commercial use

International Nuclear Information System (INIS)

1995-09-01

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 (U 3 O 8 ) per year to produce 177 MT of 4% U235 assay U 3 O 8 , 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

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.

A robust quantitative near infrared modeling approach for blend monitoring.

Science.gov (United States)

Mohan, Shikhar; Momose, Wataru; Katz, Jeffrey M; Hossain, Md Nayeem; Velez, Natasha; Drennen, James K; Anderson, Carl A

2018-01-30

This study demonstrates a material sparing Near-Infrared modeling approach for powder blend monitoring. In this new approach, gram scale powder mixtures are subjected to compression loads to simulate the effect of scale using an Instron universal testing system. Models prepared by the new method development approach (small-scale method) and by a traditional method development (blender-scale method) were compared by simultaneously monitoring a 1kg batch size blend run. Both models demonstrated similar model performance. The small-scale method strategy significantly reduces the total resources expended to develop Near-Infrared calibration models for on-line blend monitoring. Further, this development approach does not require the actual equipment (i.e., blender) to which the method will be applied, only a similar optical interface. Thus, a robust on-line blend monitoring method can be fully developed before any large-scale blending experiment is viable, allowing the blend method to be used during scale-up and blend development trials. Copyright © 2017. Published by Elsevier B.V.

Quantification of rice bran oil in oil blends

Directory of Open Access Journals (Sweden)

Mishra, R.

2012-03-01

Full Text Available 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.

Se analizaron diversos parámetros físico-químicos para la evaluación de mezclas de aceites en diferentes proporciones que incluyen: aceite de salvado de arroz físícamente refinado (PRBO: aceite de girasol (SNF y las mezclas PRBO: aceite de cártamo (SAF en diferentes proporciones. La cuantificación de la presencia del aceite de salvado de arroz en las mezclas se llevó a cabo por diferentes métodos, como cromatografía de gases (GC, cromatografía líquida (HPLC, ultrasonidos y métodos basados en otros parámetros f

Lifecycle optimized ethanol-gasoline blends for turbocharged engines

KAUST Repository

Zhang, Bo

2016-08-16

This study presents a lifecycle (well-to-wheel) analysis to determine the CO2 emissions associated with ethanol blended gasoline in optimized turbocharged engines. This study provides a more accurate assessment on the best-achievable CO2 emission of ethanol blended gasoline mixtures in future engines. The optimal fuel blend (lowest CO2 emitting fuel) is identified. A range of gasoline fuels is studied, containing different ethanol volume percentages (E0–E40), research octane numbers (RON, 92–105), and octane sensitivities (8.5–15.5). Sugarcane-based and cellulosic ethanol-blended gasolines are shown to be effective in reducing lifecycle CO2 emission, while corn-based ethanol is not as effective. A refinery simulation of production emission was utilized, and combined with vehicle fuel consumption modeling to determine the lifecycle CO2 emissions associated with ethanol-blended gasoline in turbocharged engines. The critical parameters studied, and related to blended fuel lifecycle CO2 emissions, are ethanol content, research octane number, and octane sensitivity. The lowest-emitting blended fuel had an ethanol content of 32 vol%, RON of 105, and octane sensitivity of 15.5; resulting in a CO2 reduction of 7.1%, compared to the reference gasoline fuel and engine technology. The advantage of ethanol addition is greatest on a per unit basis at low concentrations. Finally, this study shows that engine-downsizing technology can yield an additional CO2 reduction of up to 25.5% in a two-stage downsized turbocharged engine burning the optimum sugarcane-based fuel blend. The social cost savings in the USA, from the CO2 reduction, is estimated to be as much as $187 billion/year. © 2016 Elsevier Ltd

Characterization of herbal powder blends homogeneity using near-infrared spectroscopy

Directory of Open Access Journals (Sweden)

Wenlong Li

2014-11-01

Full Text Available Homogeneity of powder blend is essential to obtain uniform contents for the tablets and capsules. Near-infrared (NIR spectroscopy with fiber-optic probe was used as an on-line technique for monitoring the homogeneity of pharmaceutical blend during the blending process instead of the traditional techniques, such as high performance liquid chromatograph (HPLC method. In this paper NIRS with a SabIR diffuse reflectance fiber-optic probe was used to monitor the blending process of coptis powder and lactose (excipient with different contents, and further qualitative methods, like similarity, moving block of standard deviation and mean square were used for calculation purposes with the collected spectra after the pretreatment of multiplicative signal correction (MSC and second derivative. Correlation spectrum was used for the wavelength selection. Four different coptis were blended with lactose separately to validate the proposed method, and the blending process of "liu wei di huang" pill was also simulated in bottles to verify this method on multiple herbal blends. The overall results suggest that NIRS is a simple, effective and noninvasive technique can be successfully applied to the determination of homogeneity in the herbal blend.

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…

On the crystallization behavior of syndiotactic-b-atactic polystyrene stereodiblock copolymers, atactic/syndiotactic polystyrene blends, and aPS/sPS blends modified with sPS-b-aPS

Energy Technology Data Exchange (ETDEWEB)

Annunziata, Liana, E-mail: liana.annunziatta@univ-rennes1.fr [Organométalliques et Catalyse, UMR 6226 Sciences Chimiques CNRS, Université de Rennes 1, Campus de Beaulieu, F-35042 Rennes Cedex (France); Monasse, Bernard, E-mail: bernard.monasse@mines-paristech.fr [Mines-ParisTech, CEMEF, Centre de Mise en Forme des Matériaux, UMR CNRS 7635, Sophia Antipolis (France); Rizzo, Paola; Guerra, Gaetano [Dipartimento di Chimica e Biologia, Università degli studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano, SA (Italy); Duc, Michel [Total Petrochemicals Research Feluy, Zone Industrielle Feluy C, B-7181 Seneffe (Belgium); Carpentier, Jean-François, E-mail: jean-francois.carpentier@univ-rennes1.fr [Organométalliques et Catalyse, UMR 6226 Sciences Chimiques CNRS, Université de Rennes 1, Campus de Beaulieu, F-35042 Rennes Cedex (France)

2013-09-16

Crystallization and morphological features of syndiotactic-b-atactic polystyrene stereodiblock copolymers (sPS-b-aPS), atactic/syndiotactic polystyrene blends (aPS/sPS), and aPS/sPS blends modified with sPS-b-aPS, with different compositions in aPS and sPS, have been investigated using differential scanning calorimetry (DSC), polarized light optical microscopy (POM) and wide angle X-ray diffraction (WAXRD) techniques. For comparative purposes, the properties of parent pristine sPS samples were also studied. WAXRD analyses revealed for all the samples, independently from their composition (aPS/sPS ratio) and structure (blends, block copolymers, blends modified with block copolymers), the same polymorphic β form of sPS. The molecular weight of aPS and sPS showed opposite effects on the crystallization of 50:50 aPS/sPS blends: the lower the molecular weight of aPS, the slower the crystallization while the lower the molecular weight of sPS, the faster the crystallization. DSC studies performed under both isothermal and non-isothermal conditions, independently confirmed by POM studies, led to a clear trend for the crystallization rate at a given sPS/aPS ratio (ca. 50:50 and 20:80): sPS homopolymers > sPS-b-aPS block copolymers ∼sPS/aPS blends modified with sPS-b-aPS copolymers > sPS/aPS blends. Interestingly, sPS-b-aPS block copolymers not only crystallized faster than blends, but also affected positively the crystallization behavior of blends. At 50:50 sPS/aPS ratio, blends (Blend-2), block copolymers (Cop-1) and blends modified with block copolymers (Blend-2-mod) crystallized via spherulitic crystalline growth controlled by an interfacial process. In all cases, an instantaneous nucleation was observed. The density of nuclei in block copolymers (160,000−190,000 nuclei mm{sup −3}) was always higher than that in blends and modified blends (30,000−60,000 nuclei mm{sup −3}), even for quite different sPS/aPS ratio. At 20:80 sPS/aPS ratio, the block copolymers

A Novel Method of Extraction of Blend Component Structure from SANS Measurements of Homopolymer Bimodal Blends.

Science.gov (United States)

Smerdova, Olga; Graham, Richard S; Gasser, Urs; Hutchings, Lian R; De Focatiis, Davide S A

2014-05-01

A new method is presented for the extraction of single-chain form factors and interchain interference functions from a range of small-angle neutron scattering (SANS) experiments on bimodal homopolymer blends. The method requires a minimum of three blends, made up of hydrogenated and deuterated components with matched degree of polymerization at two different chain lengths, but with carefully varying deuteration levels. The method is validated through an experimental study on polystyrene homopolymer bimodal blends with [Formula: see text]. By fitting Debye functions to the structure factors, it is shown that there is good agreement between the molar mass of the components obtained from SANS and from chromatography. The extraction method also enables, for the first time, interchain scattering functions to be produced for scattering between chains of different lengths. [Formula: see text].

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.

Linear polarizers based on oriented polymer blends

NARCIS (Netherlands)

Jagt, H.J.B.; Dirix, Y.J.L.; Hikmet, R.A.M.; Bastiaansen, C.W.M.

1998-01-01

Linear sheet polarizers based on the anisotropic scattering of light by drawn polymer blends are introduced here. The proper selection of materials and processing conditions for the production of large-area, flexible films of phase-segregated polymer blends suitable for polarization applications are

Effect of noise in blending and deblending

NARCIS (Netherlands)

Berkhout, A.J.; Blacquière, G.

2013-01-01

If simultaneous shooting is carried out by incoherent source arrays, being the condition of blended acquisition, the deblending process generates shot records with a very low residual interference (blending noise). We found, theoretically and numerically, that deblended shot records had a better

Improvement of biodiesel methanol blends

Directory of Open Access Journals (Sweden)

Y. Datta Bharadwaz

2016-06-01

Full Text Available The main objective of this work was to improve the performance of biodiesel–methanol blends in a VCR engine by using optimized engine parameters. For optimization of the engine, operational parameters such as compression ratio, fuel blend, and load are taken as factors, whereas performance parameters such as brake thermal efficiency (Bth and brake specific fuel consumption (Bsfc and emission parameters such as carbon monoxide (CO, unburnt hydrocarbons (HC, Nitric oxides (NOx and smoke are taken as responses. Experimentation is carried out as per the design of experiments of the response surface methodology. Optimization of engine operational parameters is carried out using Derringers Desirability approach. From the results obtained it is inferred that the VCR engine has maximum performance and minimum emissions at 18 compression ratio, 5% fuel blend and at 9.03 kg of load. At this optimized operating conditions of the engine the responses such as brake thermal efficiency, brake specific fuel consumption, carbon monoxide, unburnt hydrocarbons, nitric oxide, and smoke are found to be 31.95%, 0.37 kg/kW h, 0.036%, 5 ppm, 531.23 ppm and 15.35% respectively. It is finally observed from the mathematical models and experimental data that biodiesel methanol blends have maximum efficiency and minimum emissions at optimized engine parameters.

Properties and hydration of blended cements with steelmaking slag

International Nuclear Information System (INIS)

Kourounis, S.; Tsivilis, S.; Tsakiridis, P.E.; Papadimitriou, G.D.; Tsibouki, Z.

2007-01-01

The present research study investigates the properties and hydration of blended cements with steelmaking slag, a by-product of the conversion process of iron to steel. For this purpose, a reference sample and three cements containing up to 45% w/w steel slag were tested. The steel slag fraction used was the '0-5 mm', due to its high content in calcium silicate phases. Initial and final setting time, standard consistency, flow of normal mortar, autoclave expansion and compressive strength at 2, 7, 28 and 90 days were measured. The hydrated products were identified by X-ray diffraction while the non-evaporable water was determined by TGA. The microstructure of the hardened cement pastes and their morphological characteristics were examined by scanning electron microscopy. It is concluded that slag can be used in the production of composite cements of the strength classes 42.5 and 32.5 of EN 197-1. In addition, the slag cements present satisfactory physical properties. The steel slag slows down the hydration of the blended cements, due to the morphology of contained C 2 S and its low content in calcium silicates

Succession of microbial functional communities in response to a pilot-scale ethanol-blended fuel release throughout the plume life cycle

International Nuclear Information System (INIS)

Ma, Jie; Deng, Ye; Yuan, Tong; Zhou, Jizhong; Alvarez, Pedro J.J.

2015-01-01

GeoChip, a comprehensive gene microarray, was used to examine changes in microbial functional gene structure throughout the 4-year life cycle of a pilot-scale ethanol blend plume, including 2-year continuous released followed by plume disappearance after source removal. Canonical correlation analysis (CCA) and Mantel tests showed that dissolved O 2 (which was depleted within 5 days of initiating the release and rebounded 194 days after source removal) was the most influential environmental factor on community structure. Initially, the abundance of anaerobic BTEX degradation genes increased significantly while that of aerobic BTEX degradation genes decreased. Gene abundance for N fixation, nitrification, P utilization, sulfate reduction and S oxidation also increased, potentially changing associated biogeochemical cycle dynamics. After plume disappearance, most genes returned to pre-release abundance levels, but the final functional structure significantly differed from pre-release conditions. Overall, observed successions of functional structure reflected adaptive responses that were conducive to biodegradation of ethanol-blend releases. - Highlights: • GeoChip discerned microbial functional changes through an ethanol blend plume. • The release increased gene abundance for anaerobic BTEX degradation. • The release changed key biogeochemical (N, P, C, and S) cycling gene abundance. • The functional structure did not recover 4 months after the plume attenuated. • Dissolved O 2 was the most influential factor shaping community structure. - Geochip analysis discerned adaptive shifts in microbial functional structure and controlling environmental factors throughout a 4-year life cycle of a pilot-scale ethanol blend plume

effect of effect of blend ratio on blend ratio on characteristics

African Journals Online (AJOL)

User

properties, cassava-soybean composite, wheat, bread, blend ratio ... dily growing population, an in eating and ... thermodynamic variables can produce an effect on .... these conditions. ..... Ragaee, S. et al., Pasting properties of starch and.

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.

Dielectric relaxation behaviour of (poly (vinyl formal)) (PVFO) and polyvinylidenefluoride (PVDF) blends

Science.gov (United States)

Dawande, Kiran; Patel, Swarnim; Bajpai, Rakesh; Keller, J. M.

2018-05-01

Thermally stimulated discharge currents in PVFO: PVDF blend samples of weight percentage ratio 80:20 and 95:05 prepared by the solution cast technique have been studied as function of polarizing temperature. Three distinct peaks are found at 60±10, 100±10, and 140 ±10 °C respectively. Activation energy values been calculated by initial rise method and it were found to range from 0.22 to 1.0 eV.

Blended e-learning Design: Discussion of Cultural Issues

OpenAIRE

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

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...

PAIRWISE BLENDING OF HIGH LEVEL WASTE

International Nuclear Information System (INIS)

CERTA, P.J.

2006-01-01

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

Synthesis and Characterization of Core-Shell Acrylate Based Latex and Study of Its Reactive Blends

Directory of Open Access Journals (Sweden)

Ying Nie

2008-03-01

Full Text Available Techniques in resin blending are simple and efficient method for improving the properties of polymers, and have been used widely in polymer modification field. However, polymer latex blends such as the combination of latexes, especially the latexes with water-soluble polymers, were rarely reported. Here, we report a core-shell composite latex synthesized using methyl methacrylate (MMA, butyl acrylate (BA, 2-ethylhexyl acrylate (EHA and glycidyl methacrylate (GMA as monomers and ammonium persulfate and sodium bisulfite redox system as the initiator. Two stages seeded semi-continuous emulsion polymerization were employed for constructing a core-shell structure with P(MMA-co-BA component as the core and P(EHA-co-GMA component as the shell. Results of Transmission Electron Microscopy (TEM and Dynamics Light Scattering (DLS tests confirmed that the particles obtained are indeed possessing a desired core-shell structural character. Stable reactive latex blends were prepared by adding the latex with waterborne melamine-formaldehyde resin (MF or urea-formaldehyde resin (UF. It was found that the glass transition temperature, the mechanical strength and the hygroscopic property of films cast from the latex blends present marked enhancements under higher thermal treatment temperature. It was revealed that the physical properties of chemically reactive latexes with core-shell structure could be altered via the change of crosslinking density both from the addition of crosslinkers and the thermal treatment.

Contemplating the feasibility of vermiculate blended chitosan for heavy metal removal from simulated industrial wastewater

Science.gov (United States)

Prakash, N.; Soundarrajan, M.; Arungalai Vendan, S.; Sudha, P. N.; Renganathan, N. G.

2017-12-01

Wastewater contaminated by heavy metals pose great challenges as they are non biodegradable, toxic and carcinogenic to the soil and aquifers. Vermiculite blended with chitosan have been used to remove Cr(VI) and Cd(II) from the industrial wastewater. The results indicate that the vermiculite blended with chitosan adsorb Cr(VI) and Cd(II) from industrial waste water. Batch adsorption experiments were performed as a function of pH 5.0 and 5.5 respectively for chromium and cadmium. The adsorption rate was observed to be 72 and 71 % of chromium and cadmium respectively. The initial optimum contact time for Cr(VI) was 300 min with 59.2 % adsorption and 300 min for Cd(II) with 71.5 % adsorption. Whereas, at 4-6 there is saturation, increasing the solid to liquid ratio for chitosan biopolymers increases the number of active sites available for adsorption. The optimum pH required for maximum adsorption was found to be 5.0 and 5.5 for chromium and cadmium respectively. The experimental equilibrium adsorption data were fitted using Langmuir and Freundlich equations. It was observed that adsorption kinetics of both the metal ions on vermiculite blended chitosan is well be analyzed with pseudo-second-order model. The negative free energy change of adsorption indicates that the process was spontaneous and vermiculite blended chitosan was a favourable adsorbent for both the metals.

Synthesizing optimal waste blends

International Nuclear Information System (INIS)

Narayan, V.; Diwekar, W.M.; Hoza, M.

1996-01-01

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

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...

Properties, performance, and applications of biofuel blends: a review

Directory of Open Access Journals (Sweden)

Husam Al-Mashhadani

2017-08-01

Full Text Available Biofuels such as ethanol and biodiesel derived from living plants or animal matter can be used directly in their neat forms or as blends with their fossil counterparts in internal combustion engines. Although the properties and performance of neat biofuels have been extensively reported, this is not the case for many blends. The purpose of this review is to analyze different forms of biofuel blends that are under research and development comparing their utility and performance in the two primary classes of engines, i.e., spark ignition and compression ignition engines. The fuel properties, performance and emission characteristics, advantages and disadvantages of various fuel blends are compared and discussed. The analysis reveals certain blends possess better overall fuel properties and yield better overall performance than the neat or fossil forms.

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…

Phase Behavior, Thermal Stability and Rheological Properties of PPEK/PC Blends

Institute of Scientific and Technical Information of China (English)

无

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.

Phosphor blends for high-CRI fluorescent lamps

Science.gov (United States)

Setlur, Anant Achyut [Niskayuna, NY; Srivastava, Alok Mani [Niskayuna, NY; Comanzo, Holly Ann [Niskayuna, NY; Manivannan, Venkatesan [Clifton Park, NY; Beers, William Winder [Chesterland, OH; Toth, Katalin [Pomaz, HU; Balazs, Laszlo D [Budapest, HU

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.

Performance Testing of Diesel Engine using Cardanol-Kerosene oil blend

Directory of Open Access Journals (Sweden)

Ravindra

2018-01-01

Full Text Available Awareness of environmental pollution and fossil fuel depletion has necessitated the use of biofuels in engines which have a relatively cleaner emissions. Cardanol is a biofuel, abundantly available in India, which is a by-product of cashew processing industries. In this study performance of raw Cardanol blended with kerosene has been tested in diesel engine. Volumetric blend BK30 (30% kerosene and 70% Cardanol has been used for the test. The properties like flash point, viscosity and calorific value of the blend have been determined. The test was carried out in four stroke diesel engine connected with an eddy current dynamometer. Performance of the engine has been analysed by finding the brake specific fuel consumption (BSFC and brake thermal efficiency (BTE. The results showed that the brake thermal efficiency of the blend is 29.87%, with less CO and smoke emission compared to diesel. The results were also compared with the performance of Cardanol diesel blend and Cardanol camphor oil blend, which were already tested in diesel engines by other researchers. Earlier research work reveals that the blend of 30% camphor oil and 70% Cardanol performs very closer to diesel fuel with a thermal efficiency of 29.1%. Similarly, higher brake thermal efficiency was obtained for 20% Cardanol and 80% diesel blend.

Ignition characteristics of coal blends in an entrained flow furnace

Energy Technology Data Exchange (ETDEWEB)

J. Faundez; B. Arias; F. Rubiera; A. Arenillas; X. Garcia; A.L. Gordon; J.J. Pis [Universidad de Concepcion, Concepcion (Chile)

2007-09-15

Ignition tests were carried out on blends of three coals of different rank - subbituminous, high volatile and low volatile bituminous - in two entrained flow reactors. The ignition temperatures were determined from the gas evolution profiles (CO, CO{sub 2}, NO, O{sub 2}), while the mechanism of ignition was elucidated from these profiles and corroborated by high-speed video recording. Under the experimental conditions of high carbon loading, clear interactive effects were observed for all the blends. Ignition of the lower rank coals (subbituminous, high volatile bituminous) enhanced the ignition of the higher rank coal (low volatile bituminous) in the blends. The ignition temperatures of the blends of the low rank coals (subbituminous-high volatile bituminous) were additive. However, for the rest of the blends the ignition temperatures were always closer to the lower rank coal in the blend. 21 refs., 8 figs.

Physico-Chemical, Microbiological Profiles of Blends of Tea and ...

African Journals Online (AJOL)

Sample of tea obtained from Mambilla, Nigeria highland was blended with mistletoe - a known medicinal parasitic plant of cocoa. The ratios of the blends were Tea(T)/Mistletoe (M) 90:10 10:90, 75:25, 25:75, and 50:50 while ordinary tea and mistletoes served as control samples. Chemical analyses of blends were done ...

Property Analysis of Ethanol--Natural Gasoline--BOB Blends to Make Flex Fuel

Energy Technology Data Exchange (ETDEWEB)

Alleman, Teresa L. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Yanowitz, Janet [Ecoengineering, Inc., Sharonville, OH (United States)

2016-11-01

Ten natural gasolines were analyzed for a wide range of properties, including Reid vapor pressure (RVP), benzene, sulfur, distillation, stability, metals, and aromatic content, to determine their quality. Benzene and sulfur content were sufficiently low in all but one of the samples that they could be blended without further upgrading. Four of these samples were selected to blend with blendstock for oxygenate blending (BOB) and ethanol to produce E51, E70, and E83 blends, targeting 7.8 and 9.0-psi finished fuels. The volume of each component in the blend was estimated using the Reddy model, with the assumption that the BOB and natural gasoline blend linearly and behave as a single component in the model calculations. Results show that the Reddy model adequately predicts the RVP of the finished blend for E51 and E70, but significantly underpredicts the RVP of E83 blends by nearly 2 psi. It is hypothesized that the underprediction is a function of the very low aromatic content of the E83 blends, even compared to the E51 and E70 blends.

Combustion, performance and emissions of a diesel power generator fueled with biodiesel-kerosene and biodiesel-kerosene-diesel blends

International Nuclear Information System (INIS)

Bayındır, Hasan; Işık, Mehmet Zerrakki; Argunhan, Zeki; Yücel, Halit Lütfü; Aydın, Hüseyin

2017-01-01

High percentages of biodiesel blends or neat biodiesel cannot be used in diesel engines due to high density and viscosity, and poor atomization properties that lead to some engine operational problems. Biodiesel was produced from canola oil by transesterification process. Test fuels were prepared by blending 80% of the biodiesel with 20% of kerosene (B80&K20) and 80% of the biodiesel with 10% of kerosene and 10% diesel fuel (B80&K10&D10). Fuels were used in a 4 cylinders diesel engine that was loaded with a generator. Combustion, performance and emission characteristics of the blend fuels and D2 in the diesel engine for certain loads of 3.6, 7.2 and 10.8 kW output power and 1500 rpm constant engine speed were experimented and deeply analyzed. It was found that kerosene contained blends had quite similar combustion characteristics with those of D2. Mass fuel consumption and Bscf were slightly increased for blend fuels. HC emissions slightly increased while NOx emissions considerably reduced for blends. It was resulted that high percentages of biodiesel can be a potential substitute for diesel fuel provided that it is used as blending fuel with certain amounts of kerosene. - Highlights: • Effects of kerosene and diesel addition to biodiesel in a diesel engine were investigated. • B80&K10 and B80&K10&D10 were tested and comparisons have been made with D2. • Similar fuel properties and combustion parameters have been found for all fuels. • Heat release initiated earlier for B80&K10 and B80&K10&D10. • CO and NOx emissions are lowered for B80&K10 and B80&K10&D10.

"Blending" Docent Learning: Using Google Forms Quizzes to Increase Efficiency in Interpreter Education at Fort Henry

Science.gov (United States)

Murphy, Michael P. A.

2018-01-01

The introduction of online elements to museums and cultural sites has opened up new ways for visitors to engage with the past, with nature, with culture, and all other treasures of the museum. However, docent training has lagged behind visitor-facing educational initiatives. By blending online elements into docent education programs, staff…

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...

Mechanical and thermal properties of physically-blended-plastic films

International Nuclear Information System (INIS)

Abu Issa, M. S.

1983-10-01

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.)

Perception of blended learning inventory (POBLI) - development and validation

DEFF Research Database (Denmark)

Lassesen, Berit; Rossen, Dorte Sidelmann; Stenalt, Maria Hvid

and explore how the use of blended learning affects teachers’ approaches to teaching and students’ approaches to learning in higher education. So far, there has been relatively limited research on approaches to teaching in blended learning (González 2010; Lameras et al., 2012). In one study, Ellis et al....... In order to identify appropriate uses of blended learning in Higher Education and to enable the tailoring of teaching approaches to the different needs of an increasingly diverse student body, more knowledge is needed on how to integrate blended learning in educational settings and how best to address...... a new strategic focus on 'Educational IT’ with the purpose of strengthening teaching and learning through use of online interactions. Some of the major challenges in the development of this strategy include how to, identify rationales for using blended learning, stimulate pedagogical reflections...

Reinventing medical teaching and learning for the 21st century: Blended and flipped strategies

Directory of Open Access Journals (Sweden)

Carol A Miles

2017-01-01

Full Text Available There has been a recent rapid increase in the integration of flipped and blended modes of learning into Australian university classrooms. In the move to realize the benefits of these modes of delivery, universities are spending a great deal of time focusing on course redesign and upskilling teachers to assist in the adoption of these new methods of instruction. Large-scale blended learning projects have been completed at The University of Newcastle, Australia. One such project has been the integration of flipped and blended learning strategies into the redesign of the 1st year medical science course as part of a total undergraduate medical curriculum redesign. This course involves a large number of lecturers from a wide variety of disciplines. This involved not only the redesign of this course but also the introduction of new teaching materials and learning objects. To ensure success, this work required input from three groups: the academics teaching the course, the students taking the course, and the instructional designers who create the learning objects. The University of Newcastle, Australia, was instrumental in introducing problem-based learning (PBL to medical schools in Australian universities with its initial intake of medical students in 1978 and continues the use of this methodology as its primary teaching approach. As the current project develops, it has become apparent the pioneering work previously undertaken to implement PBL, in fact, had incorporated many of the pedagogical principles and strategies of what is now considered blended learning in the flipped classroom (albeit without the technology components. This paper argues that our teachers and students will more easily adapt to the requirements inherent in blended or flipped learning due to previous familiarity with PBL strategies.

HEU to LEU conversion and blending facility: Oxide blending alternative to produce LEU oxide for commercial use

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

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 (U{sub 3} O{sub 8}) per year to produce 177 MT of 4% U235 assay U{sub 3} O{sub 8}, 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.

An investigation on chloroprene-compatibilized acrylonitrile butadiene rubber/high density polyethylene blends.

Science.gov (United States)

Ahmed, Khalil

2015-11-01

Blends of acrylonitrile butadiene rubber/high density polyethylene (NBR/HDPE) compatibilized by Chloroprene rubber (CR) were prepared. A fixed quantity of industrial waste such as marble waste (MW, 40 phr) was also included. The effect of the blend ratio and CR on cure characteristics, mechanical and swelling properties of MW-filled NBR/HDPE blends was investigated. The results showed that the MW-filled NBR/HDPE blends revealed an increase in tensile strength, tear, modulus, hardness and cross-link density for increasing weight ratio of HDPE. The minimum torque (M L) and maximum torque (M H) of blends increased with increasing weight ratio of HDPE while scorch time (ts2) cure time (tc90), compression set and abrasion loss of blends decreased with increasing weight ratio of HDPE. The blends also showed a continuous reduction in elongation at break as well as swelling coefficient with increasing HDPE amount in blends. MW filled blends based on CR provided the most encouraging balance values of overall properties.

An investigation on chloroprene-compatibilized acrylonitrile butadiene rubber/high density polyethylene blends

Directory of Open Access Journals (Sweden)

Khalil Ahmed

2015-11-01

Full Text Available Blends of acrylonitrile butadiene rubber/high density polyethylene (NBR/HDPE compatibilized by Chloroprene rubber (CR were prepared. A fixed quantity of industrial waste such as marble waste (MW, 40 phr was also included. The effect of the blend ratio and CR on cure characteristics, mechanical and swelling properties of MW-filled NBR/HDPE blends was investigated. The results showed that the MW-filled NBR/HDPE blends revealed an increase in tensile strength, tear, modulus, hardness and cross-link density for increasing weight ratio of HDPE. The minimum torque (ML and maximum torque (MH of blends increased with increasing weight ratio of HDPE while scorch time (ts2 cure time (tc90, compression set and abrasion loss of blends decreased with increasing weight ratio of HDPE. The blends also showed a continuous reduction in elongation at break as well as swelling coefficient with increasing HDPE amount in blends. MW filled blends based on CR provided the most encouraging balance values of overall properties.

Mechanical Properties of Dynamically Vulcanized Thermoplastic Polyurethane (TPU/Polybutadiene Rubber (BR Blends

Directory of Open Access Journals (Sweden)

Ji-Hoo Kim

2017-01-01

Full Text Available To obtain thermoplastic polyurethane (TPU with low hardness, dynamically vulcanized TPU/polybutadiene rubber(BR(70/30 blends were prepared. The effect of dicumyl peroxide (DCP content and stabilizers on the tensile strength and elongation at break of the dynamically vulcanized blends was examined. The tensile strength and elongation at break of the dynamically vulcanized blends decrease with increasing content of DCP. The addition of optimal content of stabilizer leads to the improvement of tensile strength and elongation at break of the blends. Also, the effect of sulfur cure systems and accelerators on the tensile strength and elongation of the blends was investigated. The tensile strength and elongation at break of all the dynamically vulcanized TPU/BR (70/30 blends using 1-step processing are not higher than those of simple TPU/BR (70/30 blends. However, the tensile strength and elongation of the dynamically vulcanized blends prepared at 8 min (mixing time using 2-step processing are higher than those of the simple blends.

A Study on Students’ Views On Blended Learning Environment

Directory of Open Access Journals (Sweden)

Meryem YILMAZ SOYLU

2006-07-01

Full Text Available 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 defined simply as a learning environment that combines technology with face-to-face learning. In other words blended learning means using a variety of delivery methods to best meet the course objectives by combining face-to-face teaching in a traditional classroom with teaching online. This article examines students’ views on blended learning environment. The study was conducted on 64 students from Department of Computer Education and Instructional Technologies in 2005–2006 fall semester in Instructional Design and Authoring Languages in PC Environment at Hacettepe University. The results showed that the students enjoyed taking part in the blended learning environment. Students’ achievement levels and their frequency of participation to forum affected their views about blended learning environment. Face-to-face interaction in blended learning application had the highest score. This result demonstrated the importance of interaction and communication for the success of on-line learning.

Meeting Diverse Learner Needs with Blended Learning

Science.gov (United States)

Owen, Hazel

2010-01-01

This article describes a 40-week Computer, Research Skills, and Projects (CRSP) blended learning course designed and implemented at Dubai Men's College. The learning employed a design using socio-constructivist principles in the blended approach to cater to the learning preferences of students. (Contains 2 figures and 1 footnote.)

Effects of blending on the properties of diesel and palm biodiesel

Science.gov (United States)

Bukkarapu, Kiran Raj; Srinivas Rahul, T.; Kundla, Sivaji; Vishnu Vardhan, G.

2018-03-01

Palm biodiesel is blended to diesel in different volume percentages to improve certain properties. This would help in having a good understanding of the dependence of the diesel properties on the biodiesel proportion. The properties of interest in the present work are density, kinematic viscosity, flash point and fire point of the blends which are determined and compared to petrodiesel. It is observed that the kinematic viscosity and density of the diesel increase with the palm biodiesel proportion and it is not preferable. Blends with higher palm content possess higher flash point and fire point. Apparently, blending worsens the conditions and hence might be of no use when compared to diesel, but when compared to neat palm biodiesel, blending helped in pulling down the density, viscosity, fire point and flash point of the latter. Using regression analysis and the properties data of respective blends, correlations are developed to predict the properties of diesel and biodiesel blends known the percentage of biodiesel added to diesel, which are validated using biodiesel and diesel blends which are not used as an input to develop them.

Thermoset Blends of an Epoxy Resin and Polydicyclopentadiene

Energy Technology Data Exchange (ETDEWEB)

Rohde, Brian J.; Le, Kim Mai; Krishnamoorti, Ramanan; Robertson, Megan L.

2016-12-13

The mechanical properties of two chemically distinct and complementary thermoset polymers were manipulated through development of thermoset blends. The thermoset blend system was composed of an anhydride-cured diglycidyl ether of bisphenol A (DGEBA)-based epoxy resin, contributing high tensile strength and modulus, and polydicyclopentadiene (PDCPD), which has a higher toughness and impact strength as compared to other thermoset polymers. Ultra-small-angle and small-angle X-ray scattering analysis explored the morphology of concurrently cured thermoset blends, revealing a macroscopically phase separated system with a surface fractal structure across blended systems of varying composition. The epoxy resin rich and PDCPD rich phases exhibited distinct glass transitions (Tg’s): the Tg observed at higher temperature was associated with the epoxy resin rich phase and was largely unaffected by the presence of PDCPD, whereas the PDCPD rich phase Tg systematically decreased with increasing epoxy resin content due to inhibition of dicyclopentadiene ring-opening metathesis polymerization. The mechanical properties of these phase-separated blends were in reasonable agreement with predictions by the rule of mixtures for the blend tensile strength, modulus, and fracture toughness. Scanning electron microscopy analysis of the tensile and fracture specimen fracture surfaces showed an increase in energy dissipation mechanisms, such as crazing, shear banding, and surface roughness, as the fraction of the more ductile component, PDPCD, increased. These results present a facile method to tune the mechanical properties of a toughened thermoset network, in which the high modulus and tensile strength of the epoxy resin can be largely retained at high epoxy resin content in the blend, while increasing the fracture toughness.

Proton exchange membranes based on PVDF/SEBS blends

Energy Technology Data Exchange (ETDEWEB)

Mokrini, A.; Huneault, M.A. [Industrial Materials Institute, National Research Council of Canada, 75 de Mortagne Blvd., Boucherville, Que. (Canada J4B 6Y4)

2006-03-09

Proton-conductive polymer membranes are used as an electrolyte in the so-called proton exchange membrane fuel cells. Current commercially available membranes are perfluorosulfonic acid polymers, a class of high-cost ionomers. This paper examines the potential of polymer blends, namely those of styrene-(ethylene-butylene)-styrene block copolymer (SEBS) and polyvinylidene fluoride (PVDF), in the proton exchange membrane application. SEBS/PVDF blends were prepared by twin-screw extrusion and the membranes were formed by calendering. SEBS is a phase-segregated material where the polystyrene blocks can be selectively functionalized offering high ionic conductivity, while PVDF insures good dimensional stability and chemical resistance to the films. Proton conductivity of the films was obtained by solid-state grafting of sulfonic acid moieties. The obtained membranes were characterized in terms of conductivity, ionic exchange capacity and water uptake. In addition, the membranes were characterized in terms of morphology, microstructure and thermo-mechanical properties to establish the blends morphology-property relationships. Modification of interfacial properties between SEBS and PVDF was found to be a key to optimize the blends performance. Addition of a methyl methacrylate-butyl acrylate-methyl methacrylate block copolymer (MMA-BA-MMA) was found to compatibilize the blend by reducing the segregation scale and improving the blend homogeneity. Mechanical resistance of the membranes was also improved through the addition of this compatibilizer. As little as 2wt.% compatibilizer was sufficient for complete interfacial coverage and lead to improved mechanical properties. Compatibilized blend membranes also showed higher conductivities, 1.9x10{sup -2} to 5.5x10{sup -3}Scm{sup -1}, and improved water management. (author)

Improving the Cold Temperature Properties of Tallow-Based Methyl Ester Mixtures Using Fractionation, Blending, and Additives

Science.gov (United States)

Elwell, Caleb

Beef tallow is a less common feedstock source for biodiesel than soy or canola oil, but it can have economic benefits in comparison to these traditional feedstocks. However, tallow methyl ester (TME) has the major disadvantage of poor cold temperature properties. Cloud point (CP) is an standard industry metric for evaluating the cold temperature performance of biodiesel and is directly related to the thermodynamic properties of the fuel's constituents. TME has a CP of 14.5°C compared with 2.3°C for soy methyl ester (SME) and -8.3°C for canola methyl ester (CME). In this study, three methods were evaluated to reduce the CP of TME: fractionation, blending with SME and CME, and using polymer additives. TME fractionation (i.e. removal of specific methyl ester constituents) was simulated by creating FAME mixtures to match the FAME profiles of fractionated TME. The fractionation yield was found to be highest at the eutectic point of methyl palmitate (MP) and methyl stearate (MS), which was empirically determined to be at a MP/(MP+MS) ratio of approximately 82%. Since unmodified TME has a MP/(MP+MS) ratio of 59%, initially only MS should be removed to produce a ratio closer to the eutectic point to reduce CP and maximize yield. Graphs relating yield (with 4:1 methyl stearate to methyl oleate carryover) to CP were produced to determine the economic viability of this approach. To evaluate the effect of blending TME with other methyl esters, SME and CME were blended with TME at blend ratios of 0 to 100%. Both the SME/TME and CME/TME blends exhibited decreased CPs with increasing levels of SME and CME. Although the CP of the SME/TME blends varied linearly with SME content, the CP of the CME/TME blends varied quadratically with CME content. To evaluate the potential of fuel additives to reduce the CP of TME, 11 different polymer additives were tested. Although all of these additives were specifically marketed to enhance the cold temperature properties of petroleum diesel or

SYSTEM APPROACH TO THE BLENDED LEARNING

Directory of Open Access Journals (Sweden)

Vladimir Kukharenko

2015-10-01

Full Text Available Currently, much attention is paid to the development of learning sour cream – a combination of traditional and distance (30-70% of training. Such training is sometimes called hybrid and referred to disruptive technologies. Purpose – to show that the use of systemic campaign in blended learning provides a high quality of education, and the technology can be devastating. The subject of the study – blended learning, object of study – Mixed learning process. The analysis results show that the combined training increases the motivation of students, qualification of teachers, personalized learning process. At the same time there are no reliable methods of assessing the quality of education and training standards. It is important that blended learning strategy to support the institutional goals and had an effective organizational model for support.

Phase Segregation in Polystyrene?Polylactide Blends

Energy Technology Data Exchange (ETDEWEB)

Leung, Bonnie; Hitchcock, Adam; Brash, John; Scholl, Andreas; Doran, Andrew

2010-06-09

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 vacuum annealing. For most of the blends examined, PS is the continuous phase with PLA existing in discrete domains or segregated to the air?polymer interface. Phase segregation was improved with further annealing. A phase inversion occurred when films of a 40:60 PS:PLA blend (0.7 wt percent loading) were annealed above the glass transition temperature (Tg) of PLA.

THE HANDBOOK OF BLENDED LEARNING:Global Perspectives, Local Designs

Directory of Open Access Journals (Sweden)

Reviewed by Alev ATES

2009-10-01

into HE administration structure and require rethinking of the ways for teaching, they provide the best way to improve student learning outcomes. Examples from New Zealand (the Massey University and the Open Polytechnic, Wales (TheUniversity of Glamorgan, USA (California-National University in teacher education, In Part Four: For-profit and online university perspectives, the University of Phoenix, Capella University and Jones International University provide different histories and programs of BL practices in local designs besides its impact on students with various demographics. Several practices and cases are able to stimulate higher educators to review the aspects and discuss issues in applying BL models in their own institutions.In Part Five: Cases of blended learning in higher education from around the world,specific case situations from twelve different countries which are Japan, Korea, China, Malaysia, Singapore, Australia, Canada, the United States, Mexico, Israel, the United Kingdom and South Africa are highlighted. These cases can provide readers a great understanding for implementation of BL according to diverse learning needs and cultures. However, I have also expected to see cases from Anadolu University in Turkey, since it is the fourth largest university in the world by enrollment and the national provider of open education since 1982 with over 1.500.000 enrollments (AU,2009. This valuable contribution could have helped to complete the global picture of distance and blended learning practices in higher education.In Part Six: Multinational blended learning perspectives, the integration of learning technologies into Europe‘s education besides BL in Africa and the Middle East and in the context of international development are highlighted. In Part Seven: Workplace, on demand, and authentic learning, emerging trends in workplace, work flow and ondemand learning are provided. The opportunities for mentoring and apprenticeship in learning in the workplace

Structural characterization of Poly aniline blended with polyacrylamide

International Nuclear Information System (INIS)

Fayek, S.A.; El-Sayed, S.M.; Sayed, W.M.

2007-01-01

Poly aniline / polyacrylamide blends in presence of different catalysts were prepared. X-ray diffraction studies reveal that the samples produced are crystalline. Optical gap of the blend in the presence of NaCIO 4 used as a catalyst is greater than that in the presence of (NH 4 ) 2 S 2 O 8 as a catalyst. The structure of polyacrylamide (PAM) blended with poly aniline (PANI) were investigated by infrared spectroscopy, Grain size was identified using scanning electron microscopy [SEM

Preparation and Characterization of Keratin/Alginate Blend Microparticles

OpenAIRE

Srisuwan, Yaowalak; Srihanam, Prasong

2018-01-01

The water-in-oil (W/O) emulsification-diffusion method was used for construction of keratin (Ker), alginate (Alg), and Ker/Alg blend microparticles. The Ker, Alg, and Ker/Alg blend solutions were used as the water phase, while ethyl acetate was used as the oil phase. Firstly, different concentrations of Ker solution was used to find suitable content. 1.6% w/v Ker solution was blended with the same concentration of the Alg solution for further microparticle construction. Results from scanning ...

Flippin' Fluid Mechanics - Comparison of Blended Classroom vs. Traditional Lecture

Science.gov (United States)

Webster, D. R.; Kadel, R. S.; Newstetter, W. C.

2017-11-01

We conducted a study of student performance in and perceptions of a blended classroom delivery of a junior-level fluid mechanics course. In the blended pedagogy, students watch short on-line videos before class, participate in interactive in-class problem solving (in dyads), and complete individualized on-line quizzes weekly. Comparisons are made among four sections of the blended classroom delivery in the period of 2013-2017 to eleven sections delivered in a traditional lecture-style format by the same instructor in 2002-2012. The results reveal dramatic improvement in student engagement, perceptions, and achievement in the blended pedagogy. For instance, the withdrawal/fail/barely-passing (WFD) rate is significantly lower for the blended classroom (8.6% vs. 16.3%; p self-perception of how-much-learned, perception of the value of the course activities, and the overall effectiveness of the course and instructor in the blended classroom.

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

International Nuclear Information System (INIS)

Wakil, M.A.; Kalam, M.A.; Masjuki, H.H.; Atabani, A.E.; Rizwanul Fattah, I.M.

2015-01-01

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 mm 2 /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

X-ray blending device

International Nuclear Information System (INIS)

Manolov, S.S.; Donchev, I.D.; Paunchev, A.N.; Atanasov, A.B.; Kerin, T.P.

1985-01-01

The X-ray blending device comprises electric motors for vertical and horizontal blending plates, electrically connected with the output of the block for format voltages and mechanically connected with the measuring potentiometers' slides. The potentiometers are respectively connected with the data inputs of the block for format voltages, the control input of which is connected with the control block output in a mode of scanning. The data outputs of the format voltage block are connected through a buffer converter, a memory block and a decoder with the data inputs of the first and second digital-to-analog converters, the outputs of which are connected with the first inputs of the first and the second comparison circuits. The second inputs of the last are linked to the slides of the first and the second potentiometers and their inputs are connected with the data inputs of the first and the second combinational logic circuits. The output of the control block in a mode of scanning is connected with the first control inputs of the first and the second combinational logic circuits and with the control inputs of the memory block and the decoder. The second and the third control units of the first and the second combinational circuits are respectively linked with the outputs for a position determination of the vertical and horizontal blending plates from the control block in a mode of scanning. The outputs of the first and the second combinational logic circuits are respectively connected with the first and the second control bridge circuits, the control outputs of which are electrically connected with the first and the second electric motors for vertical and horizontal blending plates. 1 cl., 3 figs

COOLING COIL EFFECTS ON BLENDING IN A PILOT SCALE TANK

International Nuclear Information System (INIS)

Leishear, R.; Poirier, M.; Fowley, M.; Steeper, T.

2010-01-01

Blending, or mixing, processes in 1.3 million gallon nuclear waste tanks are complicated by the fact that miles of serpentine, vertical, cooling coils are installed in the tanks. As a step toward investigating blending interference due to coils in this type of tank, a 1/10.85 scale tank and pump model were constructed for pilot scale testing. A series of tests were performed in this scaled tank by adding blue dye to visualize blending, and by adding acid or base tracers to solution to quantify the time required to effectively blend the tank contents. The acid and base tests were monitored with pH probes, which were located in the pilot scale tank to ensure that representative samples were obtained. Using the probes, the hydronium ion concentration [H + ] was measured to ensure that a uniform concentration was obtained throughout the tank. As a result of pilot scale testing, a significantly improved understanding of mixing, or blending, in nuclear waste tanks has been achieved. Evaluation of test data showed that cooling coils in the waste tank model increased pilot scale blending times by 200% in the recommended operating range, compared to previous theoretical estimates of a 10-50% increase. Below the planned operating range, pilot scale blending times were increased by as much as 700% in a tank with coils installed. One pump, rather than two or more, was shown to effectively blend the tank contents, and dual pump nozzles installed parallel to the tank wall were shown to provide optimal blending. In short, experimental results varied significantly from expectations.

Sensitivity comparison of two L-alanine doped blends to different photon energies

International Nuclear Information System (INIS)

Chen, Felipe; Vega Ramirez, Jose; Nicolucci, Patricia; Baffa, Oswaldo

2008-01-01

Full text: Blends of L-alanine (85% weight proportion) with KI (10%) and with PbI 2 (10%), these last two compounds acting as dopants, and with PVA (5%) acting as binder, were prepared in water at 80 C degrees. A blend of pure L-alanine (95%) with PVA (5%) was also prepared. The three blends were irradiated with photon beams of different energies (120 kV, 60 Co and 10 MV) with a unique dose of 30 Gy to compare their sensitivities for those three energies. EPR spectra of the three irradiated blends were recorded in a K-Band spectrometer (24 GHz) taking aliquots of about 4 mg for each blend. The energy sensitivity of a blend was defined as the peak-to-peak amplitude of its EPR spectrum central line. For the 60 Co energy (1.25 MeV) the blends presented practically the same sensitivity indicating that the presence of the dopants does not affect the sensitivity of L-alanine. For 10 MV X-rays there was an increment (around 20% - 30 %) in sensitivity for the two L-alanine doped blends compared with the pure L-alanine blend (not doped). In the case of 120 kV X-rays, the blends ala+KI and ala+PbI 2 showed an increment of 10 and 20 times, respectively, more sensitivity than the pure L-alanine blend. It is concluded that the dopants KI and PbI 2 produce a great enhance of the L-alanine sensitivity to low-energy photons. For the same dopant's content (10%) in the blend, PbI 2 showed a better performance. These results encourage us to try to enhance the sensitivity of L-alanine even more increasing the dopant's content in the blend. Application of these L-alanine doped blends in the dosimetry in diagnostic radiology could be possible. (author)

Poly(hydroxybutyrate)/cellulose acetate blend nanofiber scaffolds: Preparation, characterization and cytocompatibility

Energy Technology Data Exchange (ETDEWEB)

Zhijiang, Cai, E-mail: caizhijiang@hotmail.com [School of Textiles, Tianjin Polytechnic University, Tianjin 300387 (China); State Key Laboratory of Hollow Fiber Membrane Material and Processes, No 399 BingShuiXi Street, XiQing District, Tianjin, China, 300387 (China); Yi, Xu; Haizheng, Yang; Jia, Jianru; Liu, Yuanpei [School of Textiles, Tianjin Polytechnic University, Tianjin 300387 (China)

2016-01-01

Poly(hydroxybutyrate) (PHB)/cellulose acetate (CA) blend nanofiber scaffolds were fabricated by electrospinning using the blends of chloroform and DMF as solvent. The blend nanofiber scaffolds were characterized by SEM, FTIR, XRD, DSC, contact angle and tensile test. The blend nanofibers exhibited cylindrical, uniform, bead-free and random orientation with the diameter ranged from 80–680 nm. The scaffolds had very well interconnected porous fibrous network structure and large aspect surface areas. It was found that the presence of CA affected the crystallization of PHB due to formation of intermolecular hydrogen bonds, which restricted the preferential orientation of PHB molecules. The DSC result showed that the PHB and CA were miscible in the blend nanofiber. An increase in the glass transition temperature was observed with increasing CA content. Additionally, the mechanical properties of blend nanofiber scaffolds were largely influenced by the weight ratio of PHB/CA. The tensile strength, yield strength and elongation at break of the blend nanofiber scaffolds increased from 3.3 ± 0.35 MPa, 2.8 ± 0.26 MPa, and 8 ± 0.77% to 5.05 ± 0.52 MPa, 4.6 ± 0.82 MPa, and 17.6 ± 1.24% by increasing PHB content from 60% to 90%, respectively. The water contact angle of blend nanofiber scaffolds decreased about 50% from 112 ± 2.1° to 60 ± 0.75°. The biodegradability was evaluated by in vitro degradation test and the results revealed that the blend nanofiber scaffolds showed much higher degradation rates than the neat PHB. The cytocompatibility of the blend nanofiber scaffolds was preliminarily evaluated by cell adhesion studies. The cells incubated with PHB/CA blend nanofiber scaffold for 48 h were capable of forming cell adhesion and proliferation. It showed much better biocompatibility than pure PHB film. Thus, the prepared PHB/CA blend nanofiber scaffolds are bioactive and may be more suitable for cell proliferation suggesting that these scaffolds can be used for

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…

Supertoughened renewable PLA reactive multiphase blends system: phase morphology and performance.

Science.gov (United States)

Zhang, Kunyu; Nagarajan, Vidhya; Misra, Manjusri; Mohanty, Amar K

2014-08-13

Multiphase blends of poly(lactic acid) (PLA), ethylene-methyl acrylate-glycidyl methacrylate (EMA-GMA) terpolymer, and a series of renewable poly(ether-b-amide) elastomeric copolymer (PEBA) were fabricated through reactive melt blending in an effort to improve the toughness of the PLA. Supertoughened PLA blend showing impact strength of ∼500 J/m with partial break impact behavior was achieved at an optimized blending ratio of 70 wt % PLA, 20 wt % EMA-GMA, and 10 wt % PEBA. Miscibility and thermal behavior of the binary blends PLA/PEBA and PLA/EMA-GMA, and the multiphase blends were also investigated through differential scanning calorimetric (DSC) and dynamic mechanical analysis (DMA). Phase morphology and fracture surface morphology of the blends were studied through scanning electron microscopy (SEM) and atomic force microscopy (AFM) to understand the strong corelation between the morphology and its significant effect on imparting tremendous improvement in toughness. A unique "multiple stacked structure" with partial encapsulation of EMA-GMA and PEBA minor phases was observed for the PLA/EMA-GMA/PEBA (70/20/10) revealing the importance of particular blend composition in enhancing the toughness. Toughening mechanism behind the supertoughened PLA blends have been established by studying the impact fractured surface morphology at different zones of fracture. Synergistic effect of good interfacial adhesion and interfacial cavitations followed by massive shear yielding of the matrix was believed to contribute to the enormous toughening effect observed in these multiphase blends.

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....

Blends of synthetic and natural polymers as drug delivery systems for growth hormone.

Science.gov (United States)

Cascone, M G; Sim, B; Downes, S

1995-05-01

In order to overcome the biological deficiencies of synthetic polymers and to enhance the mechanical characteristics of natural polymers, two synthetic polymers, poly(vinyl alcohol) (PVA) and poly(acrylic acid) (PAA) were blended, in different ratios, with two biological polymers, collagen (C) and hyaluronic acid (HA). These blends were used to prepare films, sponges and hydrogels which were loaded with growth hormone (GH) to investigate their potential use as drug delivery systems. The GH release was monitored in vitro using a specific enzyme-linked immunosorbent assay. The results show that GH can be released from HA/PAA sponges and from HA/PVA and C/PVA hydrogels. The initial GH concentration used for sample loading affected the total quantity of GH released but not the pattern of release. The rate and quantity of GH released was significantly dependent on the HA or C content of the polymers.

Inkjet-Printed Organic Transistors Based on Organic Semiconductor/Insulating Polymer Blends.

Science.gov (United States)

Kwon, Yoon-Jung; Park, Yeong Don; Lee, Wi Hyoung

2016-08-02

Recent advances in inkjet-printed organic field-effect transistors (OFETs) based on organic semiconductor/insulating polymer blends are reviewed in this article. Organic semiconductor/insulating polymer blends are attractive ink candidates for enhancing the jetting properties, inducing uniform film morphologies, and/or controlling crystallization behaviors of organic semiconductors. Representative studies using soluble acene/insulating polymer blends as an inkjet-printed active layer in OFETs are introduced with special attention paid to the phase separation characteristics of such blended films. In addition, inkjet-printed semiconducting/insulating polymer blends for fabricating high performance printed OFETs are reviewed.

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.

Biocompatible electrospun polymer blends for biomedical applications.

Science.gov (United States)

Munj, Hrishikesh Ramesh; Nelson, M Tyler; Karandikar, Prathamesh Sadanand; Lannutti, John Joseph; Tomasko, David Lane

2014-10-01

Blends of natural and synthetic polymers have received considerable attention as biomaterials due to the potential to optimize both mechanical and bioactive properties. Electrospinning of biocompatible polymers is an efficient method producing biomimetic topographies suited to various applications. In the ultimate application, electrospun scaffolds must also incorporate drug/protein delivery for effective cell growth and tissue repair. This study explored the suitability of a ternary Polymethylmethacrylate-Polycaprolactone-gelatin blend in the preparation of electrospun scaffolds for biomedical applications. Tuning the blend composition allows control over scaffold mechanical properties and degradation rate. Significant improvements were observed in the mechanical properties of the blend compared with the individual components. In order to study drug delivery potential, triblends were impregnated with the model compound Rhodamine-B using sub/supercritical CO₂ infusion under benign conditions. Results show significantly distinct release profiles of the impregnated dye from the triblends. Specific factors such as porosity, degradation rate, stress relaxation, dye-polymer interactions, play key roles in impregnation and release. Each polymer component of the triblends shows distinct behavior during impregnation and release process. This affects the aforementioned factors and the release profiles of the dye. Careful control over blend composition and infusion conditions creates the flexibility needed to produce biocompatible electrospun scaffolds for a variety of biomedical applications. © 2014 Wiley Periodicals, Inc.

The combustion of coal blends in a fluidised bed reactor

Energy Technology Data Exchange (ETDEWEB)

Boavida, Dulce; Abelha, Pedro; Gulyurtlu, Ibrahim; Cabrita, Isabel

1999-07-01

Combustion studies of five coals of different origin were carried out in a laboratory scale fluidised bed combustor. Five blends prepared by mixing two coals based on their petrological characterisation, in varying amounts, were selected to study the possibility of reduction NO{sub x}, N{sub 2}O and SO{sub 2} emissions. The results showed that some blends had the opposite behaviour concerning the release of NO{sub x} and SO{sub 2} in relation to parent coals, and the emissions were higher than expected. The N{sub 2}O amounts observed were, however, in almost all blends tested, lower than predicted values. With some blends, the mixing levels intended to reduce SO{sub 2} were not always found to correspond to those for simultaneous decrease of Nox. Most of the blends studied showed some evidence of interaction between them. Varying the proportion of the blend components was observed to alter the temperatures at which interactions were stronger.

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 having a different...

Olivine-Based Blended Compounds as Positive Electrodes for Lithium Batteries

Directory of Open Access Journals (Sweden)

Christian M. Julien

2016-05-01

Full Text Available Blended cathode materials made by mixing LiFePO4 (LFP with LiMnPO4 (LMP or LiNi1/3Mn1/3Co1/3O2 (NMC that exhibit either high specific energy and high rate capability were investigated. The layered blend LMP–LFP and the physically mixed blend NMC–LFP are evaluated in terms of particle morphology and electrochemical performance. Results indicate that the LMP–LFP (66:33 blend has a better discharge rate than the LiMn1−yFeyPO4 with the same composition (y = 0.33, and NMC–LFP (70:30 delivers a remarkable stable capacity over 125 cycles. Finally, in situ voltage measurement methods were applied for the evaluation of the phase evolution of blended cathodes and gradual changes in cell behavior upon cycling. We also discuss through these examples the promising development of blends as future electrodes for new generations of Li-ion batteries.

Blended Learning Versus Traditional Lecture in Introductory Nursing Pathophysiology Courses.

Science.gov (United States)

Blissitt, Andrea Marie

2016-04-01

Currently, many undergraduate nursing courses use blended-learning course formats with success; however, little evidence exists that supports the use of blended formats in introductory pathophysiology courses. The purpose of this study was to compare the scores on pre- and posttests and course satisfaction between traditional and blended course formats in an introductory nursing pathophysiology course. This study used a quantitative, quasi-experimental, nonrandomized control group, pretest-posttest design. Analysis of covariance compared pre- and posttest scores, and a t test for independent samples compared students' reported course satisfaction of the traditional and blended course formats. Results indicated that the differences in posttest scores were not statistically significant between groups. Students in the traditional group reported statistically significantly higher satisfaction ratings than students in the blended group. The results of this study support the need for further research of using blended learning in introductory pathophysiology courses in undergraduate baccalaureate nursing programs. Further investigation into how satisfaction is affected by course formats is needed. Copyright 2016, SLACK Incorporated.

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

Computer aided techniques form an efficient approach to solve chemical product design problems such as the design of blended liquid products (chemical blending). In chemical blending, one tries to find the best candidate, which satisfies the product targets defined in terms of desired product...... 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 their compositions and a set of desired target properties of the blended product as design constraints. This blend design problem is solved using a decomposition approach, which eliminates infeasible and/or redundant candidates gradually through a hierarchy of (property) model based constraints. This decomposition...

Enhancing Students' Language Skills through Blended Learning

Science.gov (United States)

Banditvilai, Choosri

2016-01-01

This paper presents a case study of using blended learning to enhance students' language skills and learner autonomy in an Asian university environment. Blended learning represents an educational environment for much of the world where computers and the Internet are readily available. It combines self-study with valuable face-to-face interaction…

Blended Learning in Personalized Assistive Learning Environments

Science.gov (United States)

Marinagi, Catherine; Skourlas, Christos

2013-01-01

In this paper, the special needs/requirements of disabled students and cost-benefits for applying blended learning in Personalized Educational Learning Environments (PELE) in Higher Education are studied. The authors describe how blended learning can form an attractive and helpful framework for assisting Deaf and Hard-of-Hearing (D-HH) students to…

Degradable polyphosphazene/poly(alpha-hydroxyester) blends: degradation studies.

Science.gov (United States)

Ambrosio, Archel M A; Allcock, Harry R; Katti, Dhirendra S; Laurencin, Cato T

2002-04-01

Biomaterials based on the polymers of lactic acid and glycolic acid and their copolymers are used or studied extensively as implantable devices for drug delivery, tissue engineering and other biomedical applications. Although these polymers have shown good biocompatibility, concerns have been raised regarding their acidic degradation products, which have important implications for long-term implantable systems. Therefore, we have designed a novel biodegradable polyphosphazene/poly(alpha-hydroxyester) blend whose degradation products are less acidic than those of the poly(alpha-hydroxyester) alone. In this study, the degradation characteristics of a blend of poly(lactide-co-glycolide) (50:50 PLAGA) and poly[(50% ethyl glycinato)(50% p-methylphenoxy) phosphazene] (PPHOS-EG50) were qualitatively and quantitatively determined with comparisons made to the parent polymers. Circular matrices (14mm diameter) of the PLAGA, PPHOS-EG50 and PLAGA-PPHOS-EG50 blend were degraded in non-buffered solutions (pH 7.4). The degraded polymers were characterized for percentage mass loss and molecular weight and the degradation medium was characterized for acid released in non-buffered solutions. The amounts of neutralizing base necessary to bring about neutral pH were measured for each polymer or polymer blend during degradation. The poly(phosphazene)/poly(lactide-co-glycolide) blend required significantly less neutralizing base in order to bring about neutral solution pH during the degradation period studied. The results indicated that the blend degraded at a rate intermediate to that of the parent polymers and that the degradation products of the polyphosphazene neutralized the acidic degradation products of PLAGA. Thus, results from these in vitro degradation studies suggest that the PLAGA-PPHOS-EG50 blend may provide a viable improvement to biomaterials based on acid-releasing organic polymers.

"Comfort" as a Critical Success Factor in Blended Learning Courses

Science.gov (United States)

Futch, Linda S.; deNoyelles, Aimee; Thompson, Kelvin; Howard, Wendy

2016-01-01

There are substantial quantitative research and anecdotal reports on blended learning and blended learning courses. However, few research studies focus on what happens at the classroom level. This research study aims to consider the highly contextual environment of effective blended learning courses by identifying the strategies instructors use to…

Student acceptance of blended learning in Nigeria: a case study of ...

African Journals Online (AJOL)

Student acceptance of blended learning in Nigeria: a case study of Landmark University. ... instrument and the acceptance of blended learning was tested using UTAUT model. ... Keywords: Blended learning, UTAUT, technology acceptance ...

Students' experiences of blended learning across a range of postgraduate programmes.

Science.gov (United States)

Smyth, Siobhan; Houghton, Catherine; Cooney, Adeline; Casey, Dympna

2012-05-01

The article describes the students' experiences of taking a blended learning postgraduate programme in a school of nursing and midwifery. The indications to date are that blended learning as a pedagogical tool has the potential to contribute and improve nursing and midwifery practice and enhance student learning. Little is reported about the students' experiences to date. Focus groups were conducted with students in the first year of introducing blended learning. The two main themes that were identified from the data were (1) the benefits of blended learning and (2) the challenges to blended learning. The blended learning experience was received positively by the students. A significant finding that was not reported in previous research was that the online component meant little time away from study for the students suggesting that it was more invasive on their everyday life. It is envisaged that the outcomes of the study will assist educators who are considering delivering programmes through blended learning. It should provide guidance for further developments and improvements in using Virtual Learning Environment (VLE) and blended learning in nurse education. Copyright © 2011 Elsevier Ltd. All rights reserved.

Blended learning experience in teacher education: the trainees´ perspective

Directory of Open Access Journals (Sweden)

Monika Černá

2009-03-01

Full Text Available 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 the University of Pardubice, Czech Republic.

Preparation and Properties of Polyhedral Oligosilsesquioxanes/Polymers Blends

National Research Council Canada - National Science Library

Blanski, Rusty

2000-01-01

... (polycarbonate, SB rubber, etc.) resulting in a clear blend. We also report that aliphatic POSS compounds are also dispersible in high density polyethylene. The synthesis of POSS/polymer blends as well as some physical properties will be discussed.

blend4php: a PHP API for galaxy.

Science.gov (United States)

Wytko, Connor; Soto, Brian; Ficklin, Stephen P

2017-01-01

Galaxy is a popular framework for execution of complex analytical pipelines typically for large data sets, and is a commonly used for (but not limited to) genomic, genetic and related biological analysis. It provides a web front-end and integrates with high performance computing resources. Here we report the development of the blend4php library that wraps Galaxy's RESTful API into a PHP-based library. PHP-based web applications can use blend4php to automate execution, monitoring and management of a remote Galaxy server, including its users, workflows, jobs and more. The blend4php library was specifically developed for the integration of Galaxy with Tripal, the open-source toolkit for the creation of online genomic and genetic web sites. However, it was designed as an independent library for use by any application, and is freely available under version 3 of the GNU Lesser General Public License (LPGL v3.0) at https://github.com/galaxyproject/blend4phpDatabase URL: https://github.com/galaxyproject/blend4php. © The Author(s) 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Thermogenic Blend Alone or in Combination with Whey Protein Supplement Stimulates Fat Metabolism and Improves Body Composition in Mice

Science.gov (United States)

Vieira-Brock, Paula de Lima; Vaughan, Brent M.; Vollmer, David L.

2018-01-01

Background: Certain food ingredients promote thermogenesis and fat loss. Similarly, whey protein improves body composition. Due to this potential synergistic effect, a blend of thermogenic food ingredients containing African mango, citrus fruit extract, Coleus forskohlii, dihydrocapsiate, and red pepper was tested alone and in combination with a whey protein supplement for its effects on body composition in sedentary mice during high-fat diet. Objective: The objective of this study was to evaluate the interaction of thermogenic foods on improving body composition during consumption of an unhealthy diet. Materials and Methods: C57BL/6J young adult male mice (n = 12) were placed on a 60% high-fat diet for 4 weeks and subsequently randomly assigned to receive daily dosing by oral gavage of vehicle, the novel blend alone or with whey protein supplement for another 4 weeks. Body composition, thermal imaging of brown adipose tissue (BAT), mitochondrial BAT uncoupling protein 1 (UCP1), and plasma levels of leptin were assessed. Results: Novel blend alone and in combination with protein supplement attenuated body weight gain, fat, and increased surface BAT temperature in comparison to vehicle control and to baseline (P blend and whey protein supplement also significantly increased UCP1 protein expression in BAT mitochondria in comparison to vehicle control and novel blend alone (P blend stimulates thermogenesis and attenuates the gain in body weight and fat in response to high-fat diet in mice and these effects were improved when administered in combination with whey protein supplement. SUMMARY 30 days oral administration to mice of a novel blend containing African mango seed extract, citrus fruits extract, Coleus forskohlii root extract, dihydrocapsiate and red pepper fruit extract reduced body weight and fat gain in response to high-fat diet without impairing muscle mass.The novel blend stimulated thermogenesis as shown by the increased thermal imaging and UCP1 protein

Evaluation of the compatibility induced by ionizing radiation on polymeric blends

International Nuclear Information System (INIS)

Pino, Eddy S.; Machado, Luci D.B.; Feitosa, Marcos A.F.; Giovedi, Claudia

2011-01-01

To produce new polymers is a costly and time consuming task. Therefore, the utilization of existing polymers in form of blends enables to obtain new polymeric materials at a competitive cost. In this sense, polymer blending has become a growing scientific and commercial development activity. In most of the cases, polymeric blends have immiscible components and this represents an unbecoming situation on blend design. For such immiscible blends, it is required the use of compatibilizers to gain properties advantage. Compatibilization process can be achieved by chemical handling using additives and heat. On the other hand, ionizing radiation induces compatibilization by free radicals, which improve the dispersion and adhesion of the blend phases, without use of chemical additives and at room temperature. In this work, a polyamide 6.6/low-density polyethylene 75/25% wt/wt composition blend was electron beam irradiated up to 250 kGy, and thereafter mechanical tests were carried out. Tensile measurements have shown that the strength at break increases, the elongation at break decreases, the resistance to impact decreases and hardness increases when the radiation dose increases. Since this mechanical behavior is due to cross-linking and to the radiation induced blend compatibilization, this compatibility was evaluated by the approach of the glass transition temperatures for both components using DMA measurements. The results have shown that the glass transition temperatures of the blend components got closer in 8 deg C in the irradiated sample, when compared to the glass transition temperature values obtained for non-irradiated blend. (author)

Evaluation of the compatibility induced by ionizing radiation on polymeric blends

Energy Technology Data Exchange (ETDEWEB)

Pino, Eddy S.; Machado, Luci D.B., E-mail: lmachado@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Feitosa, Marcos A.F. [Centro Paula Souza, Faculdade de Tecnologia da Zona Leste, Sao Paulo, SP (Brazil); Giovedi, Claudia, E-mail: claudia.giovedi@ctmsp.mar.mil.b [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), Sao Paulo, SP (Brazil). Dept. de Tecnologia de Reatores Nucleares

2011-07-01

To produce new polymers is a costly and time consuming task. Therefore, the utilization of existing polymers in form of blends enables to obtain new polymeric materials at a competitive cost. In this sense, polymer blending has become a growing scientific and commercial development activity. In most of the cases, polymeric blends have immiscible components and this represents an unbecoming situation on blend design. For such immiscible blends, it is required the use of compatibilizers to gain properties advantage. Compatibilization process can be achieved by chemical handling using additives and heat. On the other hand, ionizing radiation induces compatibilization by free radicals, which improve the dispersion and adhesion of the blend phases, without use of chemical additives and at room temperature. In this work, a polyamide 6.6/low-density polyethylene 75/25% wt/wt composition blend was electron beam irradiated up to 250 kGy, and thereafter mechanical tests were carried out. Tensile measurements have shown that the strength at break increases, the elongation at break decreases, the resistance to impact decreases and hardness increases when the radiation dose increases. Since this mechanical behavior is due to cross-linking and to the radiation induced blend compatibilization, this compatibility was evaluated by the approach of the glass transition temperatures for both components using DMA measurements. The results have shown that the glass transition temperatures of the blend components got closer in 8 deg C in the irradiated sample, when compared to the glass transition temperature values obtained for non-irradiated blend. (author)

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 solution blending + melt compounding The effects on morphology, thermal and mechanical properties of the PVC/MMT nanocomposites were studied by varying the amount of Na-MMT and OMMT in both methods SEM and XRD analysis revealed that possible intercalated and exfoliated structures were obtained in all...... prepared by solution blending + melt compounding method Experimental values for 1 and 2 phr are larger than the calculated values which directly suggest that the MMT particles are exfoliated (C) 2010 Elsevier Ltd All rights reserved...

Semantic Modeling of Administrative Procedures from a Spanish Regional Public Administration

Directory of Open Access Journals (Sweden)

Francisco José Hidalgo López

2018-02-01

Full Text Available Over the past few years, Public Administrations have been providing systems for procedures and files electronic processing to ensure compliance with regulations and provide public services to citizens. Although each administration provides similar services to their citizens, these systems usually differ from the internal information management point of view since they usually come from different products and manufacturers. The common framework that regulations demand, and that Public Administrations must respect when processing electronic files, provides a unique opportunity for the development of intelligent agents in the field of administrative processes. However, for this development to be truly effective and applicable to the public sector, it is necessary to have a common representation model for these administrative processes. Although a lot of work has already been done in the development of public information reuse initiatives and common vocabularies standardization, this has not been carried out at the processes level. In this paper, we propose a semantic representation model of both processes models and processes for Public Administrations: the procedures and administrative files. The goal is to improve public administration open data initiatives and help to develop their sustainability policies, such as improving decision-making procedures and administrative management sustainability. As a case study, we modelled public administrative processes and files in collaboration with a Regional Public Administration in Spain, the Principality of Asturias, which enabled access to its information systems, helping the evaluation of our approach.

Blended Learning in International Nuclear Education

Energy Technology Data Exchange (ETDEWEB)

James, Z. [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

2012-03-15

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.

Blended Learning in International Nuclear Education

International Nuclear Information System (INIS)

James, Z.

2012-01-01

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

Blended Refuge and Insect Resistance Management for Insecticidal Corn

Science.gov (United States)

Crespo, Andre L B; Pan, Zaiqi; Crain, Philip R; Thompson, Stephen D; Pilcher, Clinton D; Sethi, Amit

2018-01-01

Abstract In this review, we evaluate the intentional mixing or blending of insecticidal seed with refuge seed for managing resistance by insects to insecticidal corn (Zea mays). We first describe the pest biology and farming practices that will contribute to weighing trade-offs between using block refuges and blended refuges. Case studies are presented to demonstrate how the trade-offs will differ in different systems. We compare biological aspects of several abstract models to guide the reader through the history of modeling, which has played a key role in the promotion or denigration of blending in various scientific debates about insect resistance management for insecticidal crops. We conclude that the use of blended refuge should be considered on a case-by-case basis after evaluation of insect biology, environment, and farmer behavior. For Diabrotica virgifera virgifera, Ostrinia nubilalis, and Helicoverpa zea in the United States, blended refuge provides similar, if not longer, delays in the evolution of resistance compared to separate block refuges. PMID:29220481

Inkjet-Printed Organic Transistors Based on Organic Semiconductor/Insulating Polymer Blends

Science.gov (United States)

Kwon, Yoon-Jung; Park, Yeong Don; Lee, Wi Hyoung

2016-01-01

Recent advances in inkjet-printed organic field-effect transistors (OFETs) based on organic semiconductor/insulating polymer blends are reviewed in this article. Organic semiconductor/insulating polymer blends are attractive ink candidates for enhancing the jetting properties, inducing uniform film morphologies, and/or controlling crystallization behaviors of organic semiconductors. Representative studies using soluble acene/insulating polymer blends as an inkjet-printed active layer in OFETs are introduced with special attention paid to the phase separation characteristics of such blended films. In addition, inkjet-printed semiconducting/insulating polymer blends for fabricating high performance printed OFETs are reviewed. PMID:28773772

Comparison of Model Reliabilities from Single-Step and Bivariate Blending Methods

DEFF Research Database (Denmark)

Taskinen, Matti; Mäntysaari, Esa; Lidauer, Martin

2013-01-01

Model based reliabilities in genetic evaluation are compared between three methods: animal model BLUP, single-step BLUP, and bivariate blending after genomic BLUP. The original bivariate blending is revised in this work to better account animal models. The study data is extracted from...... be calculated. Model reliabilities by the single-step and the bivariate blending methods were higher than by animal model due to genomic information. Compared to the single-step method, the bivariate blending method reliability estimates were, in general, lower. Computationally bivariate blending method was......, on the other hand, lighter than the single-step method....

Determination of the density and the viscosities of biodiesel-diesel fuel blends

Energy Technology Data Exchange (ETDEWEB)

Alptekin, Ertan; Canakci, Mustafa [Department of Mechanical Education, Kocaeli University, 41380 Kocaeli (Turkey); Alternative Fuels R and D Center, Kocaeli University, 41040 Kocaeli (Turkey)

2008-12-15

In this study, commercially available two different diesel fuels were blended with the biodiesels produced from six different vegetable oils (sunflower, canola, soybean, cottonseed, corn oils and waste palm oil). The blends (B2, B5, B10, B20, B50 and B75) were prepared on a volume basis. The key fuel properties such as density and viscosities of the blends were measured by following ASTM test methods. Generalized equations for predicting the density and viscosities for the blends were given and a mixing equation, originally proposed by Arrhenius and described by Grunberg and Nissan, was used to predict the viscosities of the blends. For all blends, it was found that there is an excellent agreement between the measured and estimated values of the density and viscosities. According to the results, the density and viscosities of the blends increased with the increase of biodiesel concentration in the fuel blend. (author)

Experimental Investigation into the Combustion Characteristics on the Co-firing of Biomass with Coal as a Function of Particle Size and Blending Ratio

Energy Technology Data Exchange (ETDEWEB)

Lkhagvadorj, Sh; Kim, Sang In; Lim, Ho; Kim, Seung Mo; Jeon, Chung Hwan [Pusan National Univ., Busan (Korea, Republic of); Lee, Byoung Hwa [Doosan Heavy Industries and Construction, Ltd., Changwon (Korea, Republic of)

2016-01-15

Co-firing of biomass with coal is a promising combustion technology in a coal-fired power plant. However, it still requires verifications to apply co-firing in an actual boiler. In this study, data from the Thermogravimetric analyzer(TGA) and Drop tube furnace(DTF) were used to obtain the combustion characteristics of biomass when co-firing with coal. The combustion characteristics were verified using experimental results including reactivity from the TGA and Unburned carbon(UBC) data from the DTF. The experiment also analyzed with the variation of the biomass blending ratio and biomass particle size. It was determined that increasing the biomass blending ratio resulted in incomplete chemical reactions due to insufficient oxygen levels because of the rapid initial combustion characteristics of the biomass. Thus, the optimum blending condition of the biomass based on the results of this study was found to be 5 while oxygen enrichment reduced the increase of UBC that occurred during combustion of blended biomass and coal.

Blended Identities: Identity Work, Equity and Marginalization in Blended Learning

Science.gov (United States)

Heikoop, Will

2013-01-01

This article is a theoretical study of the self-presentation strategies employed by higher education students online; it examines student identity work via profile information and avatars in a blended learning environment delivered through social networking sites and virtual worlds. It argues that students are faced with difficult choices when…

Change Spectroscopic, thermal and mechanical studies of PU/PVC blends

Energy Technology Data Exchange (ETDEWEB)

Hezma, A.M. [Spectroscopy Department, Physics Division, National Research Center, Giza (Egypt); Elashmawi, I.S. [Spectroscopy Department, Physics Division, National Research Center, Giza (Egypt); Physic Department, Faculty of Science, Taibah University, Al-Ula (Saudi Arabia); Rajeh, A., E-mail: a.rajeh88@yahoo.com [Physic Department, Faculty of Science, Amran University, Sa' dah (Yemen); Physics Department, Faculty of science, Mansoura University, Mansoura (Egypt); Kamal, Mustafa [Physics Department, Faculty of science, Mansoura University, Mansoura (Egypt)

2016-08-15

Blends of polyurethane (PU) and polyvinyl chloride (PVC) with different concentrations were prepared by casting method. The effects of PU on PVC blends was examined by Fourier transform-infrared (FTIR), Ultra-violet visible studies (UV/VIS.), X-ray diffraction (XRD), Thermogravimetric (TGA), Differential scanning calorimetry (DSC), and mechanical properties (stress–strain curve). The interaction between PU and PVC was examined by FT-IR through the absorbance of the N–H groups and was correlated to mechanical/thermal properties. Ultra-violet visible said that optical energy gap decrease with increasing concentration of PU. Differential scanning calorimetry results was observed a single glass transition temperature (T{sub g}) for blends this confirming existence miscibility within the blends. The causes for best thermal stability of some blends may be described by measurements of interactions between C=O groups of PU and the α-hydrogen of PVC or a dipole–dipole –C=O..Cl–C– interactions. Significant alterations in FTIR, X-ray and DSC examination shows an interactions between blends had good miscibility. X-ray shows some alterations in the intensity with additional PU. PU change the mechanical behavior of PVC through of the blends. When polyurethane content increase causes polyvinyl chloride tensile strength decreases and elongation at break increase.

Blended Learning Educational Format for Third-Year Pediatrics Clinical Rotation.

Science.gov (United States)

Langenau, Erik E; Lee, Robert; Fults, Marci

2017-04-01

Traditional medical education is shifting to incorporate learning technologies and online educational activities with traditional face-to-face clinical instruction to engage students, especially at remote clinical training sites. To describe and evaluate the effectiveness of the blended learning format (combining online and face-to-face instruction) for third-year osteopathic medical students during their pediatric rotation. Third-year medical students who completed the 4-week clerkship in pediatrics during the 2014-2015 academic year were divided into a standard learning group and a blended learning group with online activities (discussion boards, blogs, virtual patient encounters, narrated video presentations, and online training modules). Comprehensive Osteopathic Medical Achievement Test scores and final course grades were compared between the standard learning and blended learning groups. Students in the blended learning group completed a postsurvey regarding their experiences. Of 264 third-year students who completed the 4-week clerkship in pediatrics during the 2014-2015 academic year, 78 (29.5%) participated in the blended learning supplement with online activities. Of 53 students who completed the postsurvey in the blended learning group, 44 (83.0%) agreed or strongly agreed that "The integration of e-learning and face-to-face learning helped me learn pediatrics." Open-ended comments supported this overall satisfaction with the course format; however, 26 of 100 comments reflected a desire to increase the amount of clinical exposure and face-to-face time with patients. No statistical differences were seen between the standard learning (n=186) and blended learning (n=78) groups with regard to Comprehensive Osteopathic Medical Achievement Test scores (P=.321). Compared with the standard learning group, more students in the blended learning group received a final course grade of honors (P=.015). Results of this study support the use of blended learning in a

Extrudability and Consolidation of Blends between CGM and DDGS

Directory of Open Access Journals (Sweden)

C. J. R. Verbeek

2016-01-01

Full Text Available During the last decade, the global biofuels industry has experienced exponential growth. By-products such as high protein corn gluten meal (CGM and high fibre distillers dried grains with solubles (DDGS have grown in parallel. CGM has been shown to be suitable as a biopolymer; the high fibre content of DDGS reduces its effectiveness, although it is considerably cheaper. In this study, the processing behaviour of CGM and DDGS blends was evaluated and resulting extrudate properties were determined. Prior to processing, urea was used as a denaturant. DDGS : CGM ratios of 0, 33, 50, 66, and 100% were processed in a single screw extruder, which solely used dissipative heating. Blends containing DDGS were less uniformly consolidated and resulted in more dissipative heating. Blends showed multiple glass transitions, which is characteristic of mechanically compatible blends. Transmission electron microscopy revealed phase separation on a microscale, although distinct CGM or DDGS phases could not be identified. On a macroscale, optical microscopy suggested that CGM-rich blends were better consolidated, supported by visual observations of a more continuous extrudate formed during extrusion. Future work should aim to also characterize the mechanical properties of these blends to assess their suitability as either bioplastic feedstock or pelletized livestock feed.

A Phenomenology of ‘Blending in’: Beyond Emotional Regulation

Directory of Open Access Journals (Sweden)

Katie Creighton

2018-02-01

Full Text Available The phenomenon of devaluing of self for adolescent girls has been highlighted in previous qualitative research in a US cultural context. Carol Gilligan and her colleagues have documented a loss of connection to self and loss of voice. ‘Blending in’ pertains to such a loss of connection and voice. ‘Blending in’ emerges from many aspects of 8 Irish females’ retrospective qualitative phenomenological accounts of their adolescent experiences. These features of blending in include: a dumbing down of intellectual ability in order to fit in, a desire to be hidden in the group to ‘fade into the background’, to not stand out as being different, fear of being labelled by others and fear of challenging others. Blending in gives phenomenological support to Gilligan’s (1990 accounts of silencing and loss of relation to self in adolescent girls, to a rendering of self as other. This phenomenological exploration is resonant also with de Beauvoir’s Second Sex and to a loss of capacity for introversion in Western culture, echoing Jung (1921. Blending in requires firmer addressing in social and emotional education (SEE, especially regarding challenge to self-management as emotional impulse and behaviour regulation. Self-management as blending in risks being a process of loss of voice and alienation of self.

Durability of Gamma Irradiated Polymer Impregnated Blended Cement Pastes

International Nuclear Information System (INIS)

Khattab, M.M.; Abdel-Rahman, H.A.; Younes, M.M.

2010-01-01

This study is focusing on durability and performance of the neat blended cement paste as well as those of the polymer-impregnated paste towards seawater and various concentrations of magnesium sulfate solutions up to 6 months of curing. The neat blended cement paste is prepared by a partial substitution of ordinary Portland cement with 5% of active rice husk ash (RHA). These samples were cured under tap water for 7 days. Similar samples were impregnated with unsaturated polyester resin (UPE) and subjected to various doses of gamma rays ranging from 10 to 50 kGy. The results showed that the irradiated impregnated specimens gave higher values of compressive strength than the neat blended cement paste specimens. On immersing the neat blended cement specimens and polymer impregnated specimens especially that irradiated at 30 kGy in seawater and different concentrations of magnesium sulfate solutions up to 6 months of curing, the results showed that the polymer impregnated blended cement (OPC-RHA-UPE) paste have a good resistance towards aggressive media as compared to the neat blended cement (OPC-RHA) paste. The results also indicated that the sea water has a greater corrosive effect than the magnesium sulfate solutions. These results were confirmed by scanning electron microscopy (SEM) and mercury intrusion porosimetry (MIP)

Morphological, rheological and mechanical characterization of polypropylene nanocomposite blends.

Science.gov (United States)

Rosales, C; Contreras, V; Matos, M; Perera, R; Villarreal, N; García-López, D; Pastor, J M

2008-04-01

In the present work, the effectiveness of styrene/ethylene-butylene/styrene rubbers grafted with maleic anhydride (MA) and a metallocene polyethylene (mPE) as toughening materials in binary and ternary blends with polypropylene and its nanocomposite as continuous phases was evaluated in terms of transmission electron microscopy (TEM), scanning electron microscopy (SEM), oscillatory shear flow and dynamic mechanical thermal analysis (DMA). The flexural modulus and heat distortion temperature values were determined as well. A metallocene polyethylene and a polyamide-6 were used as dispersed phases in these binary and ternary blends produced via melt blending in a corotating twin-screw extruder. Results showed that the compatibilized blends prepared without clay are tougher than those prepared with the nanocomposite of PP as the matrix phase and no significant changes in shear viscosity, melt elasticity, flexural or storage moduli and heat distortion temperature values were observed between them. However, the binary blend with a nanocomposite of PP as matrix and metallocene polyethylene phase exhibited better toughness, lower shear viscosity, flexural modulus, and heat distortion temperature values than that prepared with polyamide-6 as dispersed phase. These results are related to the degree of clay dispersion in the PP and to the type of morphology developed in the different blends.

Preparation and Characterization of HPMC/PVP Blend Films Plasticized with Sorbitol

OpenAIRE

Somashekarappa, H.; Prakash, Y.; Hemalatha, K.; Demappa, T.; Somashekar, R.

2013-01-01

The aim of this present work is to investigate the effect of plasticizers like Sorbitol on microstructural and mechanical properties of hydroxypropyl methylcellulose (HPMC) and Polyvinylpyrrolidone (PVP) blend films. The pure blend and plasticized blend films were prepared by solution casting method and investigated using wide angle X-ray scattering (WAXS) method. WAXS analysis confirms that the plasticizers can enter into macromolecular blend structure and destroy the crystallinity of the f...

Theory of polymer blends

International Nuclear Information System (INIS)

Curro, J.G.; Schweizer, K.S.

1989-01-01

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

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

International Nuclear Information System (INIS)

1995-09-01

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 UF 6 to produce a UF 6 product for commercial use is one of them. This document provides data to be used in the environmental impact analysis for the UF 6 blending HEU disposition option. Resource needs, employment needs, waste and emissions from plant, hazards, accident scenarios, and intersite transportation are discussed

Modification of combustion behaviour and NO emissions by coal blending

Energy Technology Data Exchange (ETDEWEB)

Rubiera, Fernando; Arenillas, Ana; Arias, Borja; Pis, Jose J. [Department of Energy and Environment, Instituto Nacional del Carbon, CSIC, Apartado 73, 33080 Oviedo (Spain)

2002-06-20

Combustion profiles determined by TGA and experiments in a laminar entrained flow reactor (EFR) were used in this work to assess the relative combustion reactivities of different rank coals and their binary coal blends. The combustion behaviour of coal blends in TGA was greatly influenced by coal rank and the proportion of each component in the blend. Higher volatile coals exerted more influence in the low-temperature region and less reactive coals in the char combustion zone. The results in the EFR indicated that coal blends burnout and NO emissions show additivity in the case of similar nature coals. When one of the components was a high-rank coal, the burnout of the blend exhibited, in some cases, positive synergistic effects, while a clear deviation from linearity was found in NO emissions.

Positron annihilation lifetime study of interfaces in ternary polymer blends

International Nuclear Information System (INIS)

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

2013-01-01

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 (α ij ) 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, α eff , was introduced to predict the overall miscibility of ternary blends.

Controlled release of tocopherols from polymer blend films

Science.gov (United States)

Obinata, Noe

Controlled release packaging has great potential to increase storage stability of foods by releasing active compounds into foods continuously over time. However, a major limitation in development of this technology is the inability to control the release and provide rates useful for long term storage of foods. Better understanding of the factors affecting active compound release is needed to overcome this limitation. The objective of this research was to investigate the relationship between polymer composition, polymer processing method, polymer morphology, and release properties of active compounds, and to provide proof of principle that compound release is controlled by film morphology. A natural antioxidant, tocopherol was used as a model active compound because it is natural, effective, heat stable, and soluble in most packaging polymers. Polymer blend films were produced from combination of linear low density polyethylene (LLDPE) and high density polyethylene (HDPE), polypropylene (PP), or polystyrene (PS) with 3000 ppm mixed tocopherols using conventional blending method and innovative blending method, smart blending with a novel mixer using chaotic advection. Film morphologies were visualized with scanning electron microscopy (SEM). Release of tocopherols into 95% ethanol as a food simulant was measured by UV/Visible spectrophotometry or HPLC, and diffusivity of tocopherols in the polymers was estimated from this data. Polymer composition (blend proportions) and processing methods have major effects on film morphology. Four different types of morphologies, dispersed, co-continuous, fiber, and multilayer structures were developed by either conventional extrusion or smart blending. With smart blending of fixed polymer compositions, different morphologies were progressively developed with fixed polymer composition as the number of rod rotations increased, providing a way to separate effects of polymer composition and morphology. The different morphologies

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....

Experimental investigation on Performance and Emission Characteristics of J20, P20, N20 Biodiesel blends and Sound Characteristics of P20 Biodiesel blend Used in Single Cylinder Diesel Engine

Science.gov (United States)

rajasekar, R.; karthik, N.; Xavier, Goldwin

2017-05-01

Present work provides the effect of biodiesel blends and Sound Characteristics of P20 Biodiesel blend compared with Performance and emission Characteristics of diesel. Methods and analysis biodiesel blends was prepared by the Transesterification Process. Experiments were conducted in single cylinder constant speed direct injection diesel engine for various test fuels. Research is mainly focused on pongamia oil. It was observed that a 20% Pongamia oil blends and its properties were similar to diesel. The results showed that 20% Pongamia oil blends gave better performance, less in noise and emission compared with ester of Jatropha and neem oil blends. Hence Pongamia blends can be used in existing diesel engine without compromising the engine performance.

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

Tailoring the mechanical and biodegradable properties of binary blends of biomedical thermoplastic elastomer.

Science.gov (United States)

Ang, Hui Ying; Chan, Jingni; Toong, Daniel; Venkatraman, Subbu S; Chia, Sing Joo; Huang, Ying Ying

2018-03-01

Blending polymers with complementary properties capitalizes on the inherent advantages of both components, making it possible to tailor the behaviour of the resultant material. A polymer blend consisting of an elastomer and thermoplastic can help to improve the mechanical integrity of the system without compromising on its processibility. A series of blends of biodegradable Poly(L-lactide-co-ɛ-caprolactone) (PLC) and Poly-(l,l-lactide-co-glycolic acid) (PLLGA), and PLC with Poly-(d,l-lactide-co-glycolic acid) (PDLLGA) were evaluated as a potential material for a biodegradable vesicourethral connector device. Based on the Tg of the blends, PLC/PLLGA formed an immiscible mixture while PLC/PDLLGA resulted in a compatible blend. The results showed that with the blending of PLC, the failure mode of PLLGA and PDLLGA changed from brittle to ductile fracture, with an significant decreas in tensile modulus and strength. SEM images demonstrated the different blend morphologies of different compositions during degradation. Gel Permeation Chromatography (GPC) and mechanical characterization revealed the degradation behaviour of the blends in this order (fastest to slowest): PDLLGA and PLC/PDLLGA blends > PLLGA and PLC/PLLGA blends > PLC. The PLC/PLLGA (70:30) blend was recommended as a suitable for the vesicourethral connector device application, highlighting the tailoring of blends to achieve a desired mechanical performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

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.

Poly(3-hexylthiophene): TIPS-pentacene blends aiming transistor applications

Energy Technology Data Exchange (ETDEWEB)

Silva Ozório, Maiza da, E-mail: ozoriounesp@gmail.com; Nogueira, Gabriel Leonardo; Morais, Rogério Miranda; Silva Martin, Cibely da; Constantino, Carlos José Leopoldo; Alves, Neri

2016-06-01

Poly(3-hexylthiophene):6,13-bis(triisopropylsilylethynyl)-pentacene (P3HT:TP) blends with a ratio of 1:1 (wt/wt) were deposited via spin coating on anodized oxide (Al{sub 2}O{sub 3}). A phase separation of the compounds was observed, resulting in the formation of crystalline aggregates of TP molecules that segregate vertically on the surface. The form of segregation depends on the oxide surface treatment used. Spectroscopy analysis shows a higher molecular order of P3HT in the blend than for neat film and that TP molecules are also distributed in the polymeric matrix. Regarding the OFET characteristics, charge carrier mobilities of 1.2 × 10{sup −3} cm{sup 2} V{sup −1} s{sup −1} and 2.0 × 10{sup −3} cm{sup 2} V{sup −1} s{sup −1} were obtained from devices for untreated and (hexamethyldisilazane) HMDS-treated Al{sub 2}O{sub 3} gate dielectric, respectively. These results confirm that P3HT:TP blends have good potential as an active layer in organic field effect transistors (OFETs). - Highlights: • Phase separation occurs in the P3HT:TP blend. • The P3HT:TP blends form aggregates that segregate vertically to the surface. • The molecular order of the P3HT is higher for the blend than for the neat film. • Treatment of surface with HMDS influence in the formation of the aggregate • The P3HT:TP blends have great viability of using for application in transistors.

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.

Characterization of coal blends for effective utilization in thermal power plants

International Nuclear Information System (INIS)

Santhosh Raaj, S.; Arumugam, S.; Muthukrishnan, M.; Krishnamoorthy, S.; Anantharaman, N.

2016-01-01

Highlights: • This work will assist utilities to decide on the choice of coals for blending. • Conventional and advanced analytical techniques were used for characterization. • Fuel ratio, burnout profile, ash chemistry and carbon burnout are key factors. • Basic properties were additive while carbon burnout was non additive for the blends. - Abstract: This paper deals with the characterization of coal blends using various conventional and advanced analytical techniques. There has been an increasing trend in utilizing imported coals for power generation in India and utilities are resorting to blended coal firing for various reasons, both financially as well as technically. Characterization studies were carried out on 2 combinations of Indian and imported coal blends. Conventional characterization such as proximate and ultimate analysis and determination of calorific value were carried out for the raw coals and blends as per ASTM standards. Following this thermal and mineral analysis of the samples were carried out using thermo gravimetric analyzer (TGA), X-ray fluorescence spectrometer (XRF) and computer controlled scanning electron microscope (CCSEM). Combustion experiments were also conducted using drop tube furnace (DTF) to determine the burnout of the raw coals and blends. The selection of technically suitable coal combination for blending, based on these characterization studies, has been detailed.

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...

A Novel Approach for Automatic Machining Feature Recognition with Edge Blend Feature

OpenAIRE

Keong Chen Wong; Yusof Yusri

2017-01-01

This paper presents an algorithm for efficiently recognizing and determining the convexity of an edge blend feature. The algorithm first recognizes all of the edge blend features from the Boundary Representation of a part; then a series of convexity test have been run on the recognized edge blend features. The novelty of the presented algorithm lies in, instead of each recognized blend feature is suppressed as most of researchers did, the recognized blend features of this research are gone th...

Mechanical properties of HDPE/UHMWPE blends: effect of filler loading and filler treatment.

Science.gov (United States)

Lai, K L K; Roziyanna, A; Ogunniyi, D S; Zainal, Arifin M I; Azlan, Ariffin A

2004-05-01

Various blend ratios of high-density polyethylene (HDPE) and ultra high molecular weight polyethylene (UHMWPE) were prepared with the objective of determining their suitability as biomaterials. In the unfilled state, a blend of 50/50 (HDPE/UHMWPE) ratio by weight was found to yield optimum properties in terms of processability and mechanical properties. Hydroxyapatite (HA) was compounded with the optimum blend ratio. The effects of HA loading, varied from 0 to 50wt% for both filled and unfilled blends were tested for mechanical properties. It was found that the inclusion of HA in the blend led to a remarkable improvement of mechanical properties compared to the unfilled blend. In order to improve the bonding between the polymer blend and the filler, the HA used was chemically treated with a coupling agent known as 3-(trimethoxysiyl) propyl methacrylate and the treated HA was mixed into the blend. The effect of mixing the blend with silane-treated HA also led to an overall improvement of mechanical properties.

Transcriptional Response in Mouse Thyroid Tissue after 211At Administration: Effects of Absorbed Dose, Initial Dose-Rate and Time after Administration.

Directory of Open Access Journals (Sweden)

Nils Rudqvist

Full Text Available 211At-labeled radiopharmaceuticals are potentially useful for tumor therapy. However, a limitation has been the preferential accumulation of released 211At in the thyroid gland, which is a critical organ for such therapy. The aim of this study was to determine the effect of absorbed dose, dose-rate, and time after 211At exposure on genome-wide transcriptional expression in mouse thyroid gland.BALB/c mice were i.v. injected with 1.7, 7.5 or 100 kBq 211At. Animals injected with 1.7 kBq were killed after 1, 6, or 168 h with mean thyroid absorbed doses of 0.023, 0.32, and 1.8 Gy, respectively. Animals injected with 7.5 and 100 kBq were killed after 6 and 1 h, respectively; mean thyroid absorbed dose was 1.4 Gy. Total RNA was extracted from pooled thyroids and the Illumina RNA microarray platform was used to determine mRNA levels. Differentially expressed transcripts and enriched GO terms were determined with adjusted p-value 1.5, and p-value <0.05, respectively.In total, 1232 differentially expressed transcripts were detected after 211At administration, demonstrating a profound effect on gene regulation. The number of regulated transcripts increased with higher initial dose-rate/absorbed dose at 1 or 6 h. However, the number of regulated transcripts decreased with mean absorbed dose/time after 1.7 kBq 211At administration. Furthermore, similar regulation profiles were seen for groups administered 1.7 kBq. Interestingly, few previously proposed radiation responsive genes were detected in the present study. Regulation of immunological processes were prevalent at 1, 6, and 168 h after 1.7 kBq administration (0.023, 0.32, 1.8 Gy.

Fuel Property Blend Model

Energy Technology Data Exchange (ETDEWEB)

Pitz, William J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mehl, Marco [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wagnon, Scott J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zhang, Kuiwen [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kukkadapu, Goutham [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Westbrook, Charles K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2017-01-12

The object of this project is to develop chemical models and associated correlations to predict the blending behavior of bio-derived fuels when mixed with conventional fuels like gasoline and diesel fuels.

20 CFR 410.610 - Administrative actions that are initial determinations.

Science.gov (United States)

2010-04-01

... determinations. 410.610 Section 410.610 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE...) Withdrawal of claim or cancellation of withdrawal request. When a request for withdrawal of a claim, or a request for cancellation of a “request for withdrawal” of a claim, is denied by the Administration, the...

Blended e-learning Design: Discussion of Cultural Issues

Directory of Open Access Journals (Sweden)

Ahmed A 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.

optical properties and morphological structure of Eb-Irradiated LDPE / P P Blends

International Nuclear Information System (INIS)

Ali, Z.I.; Said, H.M.; Youssef, H.A.; Saleh, H.H.; Abdel Monem, N.M.

2004-01-01

Blending is an effective method for improving the physical and chemical properties of homopolymers. however, the problem of phase separation often in some polymer blends occurs due to incompatibility of homopolymer which impairs the expected physico- chemical properties of blends. in this study , isotactic polypropylene, (P P), was blended with low density polyethylene, (LDPE), in the presence of various ratios of polyfunctional monomer, (PFM), namely trimethylol propane trimethacrylate, (TMPTMA), as a crosslinking and/or compatibilizing agents. the electron beam irradiation of the investigated LDPE/PP blends was carried out at different irradiation doses up to 50 kGy to improve the compatibility of LDPE/PP blends. the dye affinity of disperse and basic dyes in LDPE, PP and LDPE/PP blends was investigated in terms of color strength and visible absorbance intensities. in addition, the microstructures of the investigated samples have been studied and it is considered as an indication of the compatibility of LDPE/PP blend. the results show that the unmodified and modified LDPE samples exhibit the highest values of both color strength and visible absorbance intensities compared with unmodified and modified PP samples. also the intensities of these values in the LDPE/PP blends decrease as the PP content increases in the blend . in addition, the increase of EB irradiation dose and PFM ratios leads to an increase in the values of color strength and visible absorbance intensities. moreover, the affinity of all investigated samples towards disperse dye is being more pronounced than the basic dye. the interfacial adhesion of LDPE/PP blend could be enhanced by adding crosslinking agent, (TMPTMA), and EB irradiation process with different irradiation doses. the obtained data for the microstructures of all the investigated samples support that the EB irradiation beside the incorporation of PEM into the homopolymer matrix remarkably improve the compatibility of the polymer blend

Study on properties of poly(vinyl alcohol/polyacrylonitrile blend film

Directory of Open Access Journals (Sweden)

Guoquan Zhu

2013-01-01

Full Text Available In this work, a series of poly(vinyl alcohol (PVA/polyacrylonitrile (PAN blend films with different PAN mole contents were prepared by casting the polymer blend solution in dimethylsulfoxide (DMSO. Surface morphologies of PVA/PAN blend films were analyzed by Scanning Electronic Microscopy (SEM and Atomic Force Microscopy (AFM. Thermal, mechanical, and chemical properties of PVA/PAN blend films were investigated by Differential Scanning Calorimetry (DSC, Thermogravimetric Analysis (TGA, Tensile Tests, and Surface Contact Angle Tests. The results showed that the introduction of PAN could exert marked effects on the properties of PVA films.

Blended learning in paediatric emergency medicine: preliminary analysis of a virtual learning environment.

Science.gov (United States)

Spedding, Ruth; Jenner, Rachel; Potier, Katherine; Mackway-Jones, Kevin; Carley, Simon

2013-04-01

Paediatric emergency medicine (PEM) currently faces many competing educational challenges. Recent changes to the working patterns have made the delivery of effective teaching to trainees extremely difficult. We developed a virtual learning environment, on the basis of socioconstructivist principles, which allows learning to take place regardless of time or location. The aim was to evaluate the effectiveness of a blended e-learning approach for PEM training. We evaluated the experiences of ST3 trainees in PEM using a multimodal approach. We classified and analysed message board discussions over a 6-month period to look for evidence of practice change and learning. We conducted semistructured qualitative interviews with trainees approximately 5 months after they completed the course. Trainees embraced the virtual learning environment and had positive experiences of the blended approach to learning. Socioconstructivist learning did take place through the use of message boards on the virtual learning environment. Despite their initial unfamiliarity with the online learning system, the participants found it easy to access and use. The participants found the learning relevant and there was an overlap between shop floor learning and the online content. Clinical discussion was often led by trainees on the forums and these were described as enjoyable and informative. A blended approach to e-learning in basic PEM is effective and enjoyable to trainees.

Generator Set Durability Testing Using 25% ATJ Fuel Blend

Science.gov (United States)

2016-02-01

UNCLASSIFIED UNCLASSIFIED 3 Table 1. Chemical & Physical Properties of Evaluated 25% ATJ Blend Test ASTM Method Units SwRI Sample ID...25% ATJ Blend Test ASTM Method Units SwRI Sample ID CL15-8613 Results Min Max Flash Point D93 °C 56.5 38 Density D4052 Test...Chemical & Physical Properties of Evaluated 25% ATJ Blend Test ASTM Method Units SwRI Sample ID CL15-8613 Results Min Max Fuel System Icing Inhibitor

Investigation on the effect of blending ratio and airflow rate on syngas profile produced from co-gasification of blended feedstock

Directory of Open Access Journals (Sweden)

Inayat Muddasser

2017-01-01

Full Text Available Shortages of feedstock supply due to seasonal availability, high transportation costs, and lack of biomass market are creating serious problems in continues operation of bioenergy industry. Aiming at this problem, utilization of blended feedstock is proposed. In this work blends of two different biomasses (wood and coconut shells were co-gasified using externally heated downdraft gasifier. The effects of varying biomass blending ratio and airflow rate on gaseous components of syngas and its heating value were investigated. The results obtained from the experiments revealed that W20:CS80 blend yielded higher values for H2 (20 Vol.% and HHV (18 MJ/Nm3 as compared to the other blends. The higher airflow rate has a negative effect on syngas profile and heating value. The CO and CH4 were observed higher at the start of the process, however, CO was observed decreasing afterward, and the CH4 dropped to 5.0 Vol.%. The maximum H2 and CH4 were obtained at 2.5 LPM airflow rate. The process was noticed more stable at low air flow rates. The HHV was observed higher at the start of process at low airflow rate. It is concluded that low airflow rate and a higher ratio of coconut shells can improve the syngas quality during co-gasification.

Toughening mechanisms in interfacially modified HDPE/thermoplastic starch blends.

Science.gov (United States)

Taguet, Aurélie; Bureau, Martin N; Huneault, Michel A; Favis, Basil D

2014-12-19

The mechanical behavior of polymer blends containing 80 wt% of HDPE and 20 wt% of TPS and compatibilized with HDPE-g-MA grafted copolymer was investigated. Unmodified HDPE/TPS blends exhibit high fracture resistance, however, the interfacial modification of those blends by addition of HDPE-g-MA leads to a dramatic drop in fracture resistance. The compatibilization of HDPE/TPS blends increases the surface area of TPS particles by decreasing their size. It was postulated that the addition of HDPE-g-MA induces a reaction between maleic anhydride and hydroxyl groups of the glycerol leading to a decrease of the glycerol content in the TPS phase. This phenomenon increases the stiffness of the modified TPS particles and stiffer TPS particles leading to an important reduction in toughness and plastic deformation, as measured by the EWF method. It is shown that the main toughening mechanism in HDPE/TPS blends is shear-yielding. This article demonstrates that stiff, low diameter TPS particles reduce shear band formation and consequently decrease the resistance to crack propagation. Copyright © 2014 Elsevier Ltd. All rights reserved.

How do you design a good study start for blended and distance learning courses?

DEFF Research Database (Denmark)

Christensen, Inger-Marie F.

2016-01-01

One of the challenges of blended and distance learning is to engage and motivate students to particpate actively online. This paper describes how Gilly Salmon's 5-stage model and e-tivities concept can be used to scaffold students' learning online and support the development of a dynamic learning...... environment in which students are comfortable contributing and responding to each other's contributions. The author, furthermore, presents a 4-stage model, an adapted version of the 5-stage model recommended for blended learning contexts and in contexts where you work with experienced online students....... The main point of both models is that initially in a course 1 or 2 phases with informal and social activities online must be included to support students in getting access to the virtual learning environments and becoming confident with the role of online student. Then one can move on to activities...

Learning Design for a Successful Blended E-learning Environment: Cultural Dimensions

OpenAIRE

Al-Huwail, N.; Gulf Univ. for Science & Technology; Al-Sharhan, S.; Gulf Univ. for Science & Technology; Al-Hunaiyyan, A.; Gulf Univ. for Science & Technology

2007-01-01

Blended e-learning is becoming an educational issue especially with the new development of e-learning technology and globalization. This paper presents a new framework for delivery environment in blended e-learning. In addition, new concepts related to the learning strategies and multimedia design in blended e-learning are introduced. The work focuses on the critical cultural factors that affect a blended elearning system. Since it is common that good systems may fail due to cultural issues, ...

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...

Blended learning in health education: three case studies

NARCIS (Netherlands)

de Jong, N.; Savin-Baden, M.; Cunningham, A.M.; Verstegen, D.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

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...

Blended Learning Implementation in “Guru Pembelajar” Program

Science.gov (United States)

Mahdan, D.; Kamaludin, M.; Wendi, H. F.; Simanjuntak, M. V.

2018-02-01

The rapid development of information and communication technology (ICT), especially the internet, computers and communication devices requires the innovation in learning; one of which is Blended Learning. The concept of Blended Learning is the mixing of face-to-face learning models by learning online. Blended learning used in the learner teacher program organized by the Indonesian department of education and culture that a program to improve the competence of teachers, called “Guru Pembelajar” (GP). Blended learning model is perfect for learning for teachers, due to limited distance and time because online learning can be done anywhere and anytime. but the problems that arise from the implementation of this activity are many teachers who do not follow the activities because teachers, especially the elderly do not want to follow the activities because they cannot use computers and the internet, applications that are difficult to understand by participants, unstable internet connection in the area where the teacher lives and facilities and infrastructure are not adequate.

Blended learning in surgery using the Inmedea Simulator.

Science.gov (United States)

Funke, Katrin; Bonrath, Esther; Mardin, Wolf Arif; Becker, Jan Carl; Haier, Joerg; Senninger, Norbert; Vowinkel, Thorsten; Hoelzen, Jens Peter; Mees, Soeren Torge

2013-02-01

Recently, medical education in surgery has experienced several modifications. We have implemented a blended learning module in our teaching curriculum to evaluate its effectiveness, applicability, and acceptance in surgical education. In this prospective study, the traditional face-to-face learning of our teaching curriculum for fourth-year medical students (n = 116) was augmented by the Inmedea Simulator, a web-based E-learning system, with six virtual patient cases. Student results were documented by the system and learning success was determined by comparing patient cases with comparable diseases (second and sixth case). The acceptance among the students was evaluated with a questionnaire. After using the Inmedea Simulator, correct diagnoses were found significantly (P blended learning (score 2.5 ± 1.2) to conventional teaching. The blended learning approach using the Inmedea Simulator was highly appreciated by our medical students and resulted in a significant learning success. Blended learning appears to be a suitable tool to complement traditional teaching in surgery.

Half-metallic zinc-blende pnictides in real environments

International Nuclear Information System (INIS)

Shi Lijie; Liu Banggui

2005-01-01

The structural stability of half-metallic zinc-blende pnictides and the robustness of their half-metallic ferromagnetism in the presence of tetragonal and orthorhombic crystalline deformations are studied using a full-potential linear augmented plane wave method within the density-functional theory. The total energies of zinc-blende MnAs, CrAs, and CrSb are proved to increase with deformation increase, in contrast to those of other zinc-blende half-metallic pnictides, and therefore these three are stable against the deformations but the others are not. This is consistent with the experimental fact that only these three have been fabricated. On the other hand, the half-metallic ferromagnetism of the latter two is proved to be robust enough to survive large crystal deformations. This implies that half-metallic ferromagnetism may be achieved experimentally even in substantially deformed zinc-blende ultrathin films or layers of CrAs and CrSb in real environments

Global Optimization of Nonlinear Blend-Scheduling Problems

Directory of Open Access Journals (Sweden)

Pedro A. Castillo Castillo

2017-04-01

Full Text Available The scheduling of gasoline-blending operations is an important problem in the oil refining industry. This problem not only exhibits the combinatorial nature that is intrinsic to scheduling problems, but also non-convex nonlinear behavior, due to the blending of various materials with different quality properties. In this work, a global optimization algorithm is proposed to solve a previously published continuous-time mixed-integer nonlinear scheduling model for gasoline blending. The model includes blend recipe optimization, the distribution problem, and several important operational features and constraints. The algorithm employs piecewise McCormick relaxation (PMCR and normalized multiparametric disaggregation technique (NMDT to compute estimates of the global optimum. These techniques partition the domain of one of the variables in a bilinear term and generate convex relaxations for each partition. By increasing the number of partitions and reducing the domain of the variables, the algorithm is able to refine the estimates of the global solution. The algorithm is compared to two commercial global solvers and two heuristic methods by solving four examples from the literature. Results show that the proposed global optimization algorithm performs on par with commercial solvers but is not as fast as heuristic approaches.

Compatibilizing Bulk Polymer Blends by Using Organoclays

Science.gov (United States)

Si, Mayu; Gersappe, Dilip; Zhang, Wenhua; Ade, Harald; Rafailovich, Miriam; Sokolov, Jonathan; Rudomen, Gregory; Schwartz, Bradley; Fisher, Robert

2004-03-01

We investigated the compatiblizing performance of organoclays on melt mixed binary and tertiary polymer blends, such as, PS/PMMA, PC/SAN, PS/PMMA/PVC and PS/PMMA/PE. These polymer blends were characterized by TEM, STXM, DSC and DMA. TEM and STXM photographs show that the addition of organoclays into polymer blends drastically reduces the average domain size of the component phases. And the organoclay goes to the interfacial region between the different polymers and effectively slows down the domain size increasing during high temperature annealing. DMA and DSC results show the effect of organoclays on the mechanical properties and glass transitions temperature, which indicates the compatibilization on the molecular level. The generalized compatibilization induced by the nanoscale fillers for blends can be explained in terms of mean field models where the reduction of interfacial tension induced by in-situ grafting is counterbalanced by the increased bending energy due to the rigidity of the filler. This in turn can be shown to be a function of the degree of exfoliation, aspect ratio, and polymer filler interactions. Supported by NSF funded MRSEC at Stony Brook

Tribological Characteristics Evaluation of Mustard Oil Blends

Directory of Open Access Journals (Sweden)

Mohammed Hassan Jabal

2018-03-01

Full Text Available A progressive increase in the desire for environmentally friendly lubricants by users and strict government regulations for the use of these lubricants has provided an opportunity to use plant oils as biodegradable lubricants, therefore vegetable oils have been investigated to replace oil lubricants because of their maintaining the conditions of nature (environment properties. In this paper, the influences of the blending ratio of mustard seeds oil with commercial mineral oil (SAE40 on the tribological characteristics were investigated and compared with mineral oil using the four-ball tribotester. Mustard seeds oil was blended with mineral oil at a volumetric ratio ranging from 22.5 to 90%. All experimental works were confirmed to ASTM D4172-B standard. The results exhibit that some blends of mustard seeds oil with mineral oil have lower wear scar diameter, friction torque, Friction coefficient and a higher parameter of flash temperature value compared to mineral oil and neat mustard seed oil. In conclusion, the mustard seed oil blend (MU22.5 shows a better anti-wear and anti-friction performance compared to oil samples. Therefore, mustard seeds oil has the potential to be used as a lubricant of mating surfaces.

Reactivity and NO emissions of coal blends during combustion

Energy Technology Data Exchange (ETDEWEB)

B. Arias; R.I. 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

This work is focussed on burnout and NO emissions during coal blend combustion. Two different approaches were used. In a first step, experimental work was carried out in a laminar entrained flow reactor (EFR) and then computational techniques were applied to improve the burnout prediction of coals and blend during the experiments. A preliminary study on the combustibility of the samples was made using a thermogravimetric analyser. An entrained flow reactor was employed to study the behaviour of coals and blends at high heating rate and short residence times. Burnout and NO emissions were measured during these experiments. Two methods were used to modelling the combustion in the entrained flow reactor: a commercial CFD code and an advanced char burnout model. Experiments done in the EFR showed that burnout and NO emissions of some blends can be predicted from the weighted average of the values of individual coals, especially when blended coals have the same rank. When a blend is made with coals of different rank, some deviations were observed with respect to the averaged values in burnout and especially in NOx emissions. Burnouts predicted with a commercial CFD code were higher than the experimental values. The use of an advanced char burnout model improved greatly the results, showing the advantages of coupling these two mathematical techniques. 9 refs., 7 figs., 2 tabs.

Blended learning: how can we optimise undergraduate student engagement?

Science.gov (United States)

Morton, Caroline E; Saleh, Sohag N; Smith, Susan F; Hemani, Ashish; Ameen, Akram; Bennie, Taylor D; Toro-Troconis, Maria

2016-08-04

Blended learning is a combination of online and face-to-face learning and is increasingly of interest for use in undergraduate medical education. It has been used to teach clinical post-graduate students pharmacology but needs evaluation for its use in teaching pharmacology to undergraduate medical students, which represent a different group of students with different learning needs. An existing BSc-level module on neuropharmacology was redesigned using the Blended Learning Design Tool (BLEnDT), a tool which uses learning domains (psychomotor, cognitive and affective) to classify learning outcomes into those taught best by self-directed learning (online) or by collaborative learning (face-to-face). Two online courses were developed, one on Neurotransmitters and the other on Neurodegenerative Conditions. These were supported with face-to-face tutorials. Undergraduate students' engagement with blended learning was explored by the means of three focus groups, the data from which were analysed thematically. Five major themes emerged from the data 1) Purpose and Acceptability 2) Structure, Focus and Consolidation 3) Preparation and workload 4) Engagement with e-learning component 5) Future Medical Education. Blended learning was acceptable and of interest to undergraduate students learning this subject. They expressed a desire for more blended learning in their courses, but only if it was highly structured, of high quality and supported by tutorials. Students identified that the 'blend' was beneficial rather than purely online learning.

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.

An Integrated Methodology for Design of Tailor-Made Blended Products

DEFF Research Database (Denmark)

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

2012-01-01

is 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....

Cyanoresin, cyanoresin/cellulose triacetate blends for thin film, dielectric capacitors

Science.gov (United States)

Yen, Shiao-Ping S. (Inventor); Lewis, Carol R. (Inventor); Cygan, Peter J. (Inventor); Jow, T. Richard (Inventor)

1996-01-01

Non brittle dielectric films are formed by blending a cyanoresin such as cyanoethyl, hydroxyethyl cellulose (CRE) with a compatible, more crystalline resin such as cellulose triacetate. The electrical breakdown strength of the blend is increased by orienting the films by uniaxial or biaxial stretching. Blends of high molecular weight CRE with high molecular weight cyanoethyl cellulose (CRC) provide films with high dielectric constants.

Blending Face-to-Face and Internet-Based Interventions for the Treatment of Mental Disorders in Adults: Systematic Review.

Science.gov (United States)

Erbe, Doris; Eichert, Hans-Christoph; Riper, Heleen; Ebert, David Daniel

2017-09-15

Many studies have provided evidence for the effectiveness of Internet-based stand-alone interventions for mental disorders. A newer form of intervention combines the strengths of face-to-face (f2f) and Internet approaches (blended interventions). The aim of this review was to provide an overview of (1) the different formats of blended treatments for adults, (2) the stage of treatment in which these are applied, (3) their objective in combining face-to-face and Internet-based approaches, and (4) their effectiveness. Studies on blended concepts were identified through systematic searches in the MEDLINE, PsycINFO, Cochrane, and PubMed databases. Keywords included terms indicating face-to-face interventions ("inpatient," "outpatient," "face-to-face," or "residential treatment"), which were combined with terms indicating Internet treatment ("internet," "online," or "web") and terms indicating mental disorders ("mental health," "depression," "anxiety," or "substance abuse"). We focused on three of the most common mental disorders (depression, anxiety, and substance abuse). We identified 64 publications describing 44 studies, 27 of which were randomized controlled trials (RCTs). Results suggest that, compared with stand-alone face-to-face therapy, blended therapy may save clinician time, lead to lower dropout rates and greater abstinence rates of patients with substance abuse, or help maintain initially achieved changes within psychotherapy in the long-term effects of inpatient therapy. However, there is a lack of comparative outcome studies investigating the superiority of the outcomes of blended treatments in comparison with classic face-to-face or Internet-based treatments, as well as of studies identifying the optimal ratio of face-to-face and Internet sessions. Several studies have shown that, for common mental health disorders, blended interventions are feasible and can be more effective compared with no treatment controls. However, more RCTs on effectiveness and

Presence and Perceived Learning in Different Higher Education Blended Learning Environments

Science.gov (United States)

Khodabandelou, Rouhollah; Jalil, Habibah Ab; Ali, Wan Zah Wan; Daud, Shaffe Mohd

2015-01-01

Blended learning as "third generation" of distance learning has the potential to offer multimethod instruction through the blend, to leverage the strengths of current online and traditional instructions. Therefore, higher education institutions having recognized the fact that blended learning is beneficial, adopted this alternative…

Determination of gel content and SEM morphology for sago-PVA blends film

International Nuclear Information System (INIS)

Sarada Idris; Zulkafli Ghazali; Kamarudin Hashim

2006-01-01

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)

Properties of PET/PLA Electrospun Blends

Science.gov (United States)

Li, Kevin; Cebe, Peggy

2012-02-01

Electrospun membranes were fabricated from poly(ethylene terephthalate), PET, co-spun with poly(lactic acid), PLA. The PLA contained 2% of the D-isomer, which served to limit the overall degree of crystallinity. Membranes were deposited from blended solutions of PET/PLA in hexafluoroisopropanol. The PET/PLA composition ranged from 0/100, 75/25, 50/50, 25/75, and 100/0. Electrospun membranes were made using either a static flat plate or a rotating wheel as the counter electrode, yielding unoriented mats or highly oriented tapes, respectively. We report on our investigation of the crystallinity, crystal perfection, and mechanical properties of these materials using differential scanning calorimetry, wide and small angle X-ray scattering, and dynamic mechanical analysis. In particular, we study the ability of one blend component (PET) to crystallize in the presence of existing crystals of the second blend component (PLA) which crystallizes first and at a lower temperature than PET.

Blending of phased array data

Science.gov (United States)

Duijster, Arno; van Groenestijn, Gert-Jan; van Neer, Paul; Blacquière, Gerrit; Volker, Arno

2018-04-01

The use of phased arrays is growing in the non-destructive testing industry and the trend is towards large 2D arrays, but due to limitations, it is currently not possible to record the signals from all elements, resulting in aliased data. In the past, we have presented a data interpolation scheme `beyond spatial aliasing' to overcome this aliasing. In this paper, we present a different approach: blending and deblending of data. On the hardware side, groups of receivers are blended (grouped) in only a few transmit/recording channels. This allows for transmission and recording with all elements, in a shorter acquisition time and with less channels. On the data processing side, this blended data is deblended (separated) by transforming it to a different domain and applying an iterative filtering and thresholding. Two different filtering methods are compared: f-k filtering and wavefield extrapolation filtering. The deblending and filtering methods are demonstrated on simulated experimental data. The wavefield extrapolation filtering proves to outperform f-k filtering. The wavefield extrapolation method can deal with groups of up to 24 receivers, in a phased array of 48 × 48 elements.

Teaching Shakespeare through blended learning

Directory of Open Access Journals (Sweden)

Lesley Hawkes

2018-03-01

Full Text Available This paper describes and discusses experimentation with the use of blended learning in teaching Shakespeare. Previous iterations of the subject in a traditional lecture and tutorial format had seen a decline in student attendance and a fall in student achievement at the higher grade levels. A further complicating issue was the range of expectations from the cohort, which comprised students from Creative Writing, Drama, and Education, a factor which also highlights the cross-disciplinary nature of teaching Shakespeare. A blended learning and lectorial format was employed to facilitate small group discussion of the plays in conjunction with a wider social and historical overview. Student feedback indicated that the changes to the delivery method were received positively, although some questions do remain concerning levels of student engagement and the specific disciplinary needs of student cohorts. The findings of the teaching of this subject will translate usefully to other fields and disciplines, especially as more and more subjects take up blended learning. The findings indicate that it is not enough to take up new technologies in the teaching of a unit. The learning environment must also be rethought and reconceptualised.

Analytical characterization of pure and blended watermelon (citrullus lanatus) oil: impact of blending on oxidative stability

International Nuclear Information System (INIS)

Azeem, M.W.; Nadeem, M.

2015-01-01

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% (B 1, B2, B3 and B4) and referenced with a control (100% watermelon oil). All the blends were stored in transparent PET bottles at ambient temperature (25-28 degree C) 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 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. delta 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 (meqO/sub 2//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. (author)

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.

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

International Nuclear Information System (INIS)

1998-12-01

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

Phenolic composition and mouthfeel characteristics resulting from blending Chilean red wines.

Science.gov (United States)

Cáceres-Mella, Alejandro; Peña-Neira, Alvaro; Avilés-Gálvez, Pamela; Medel-Marabolí, Marcela; Del Barrio-Galán, Rubén; López-Solís, Remigio; Canals, Joan Miquel

2014-03-15

The blending of wine is a common practice in winemaking to improve certain characteristics that are appreciated by consumers. The use of some cultivars may contribute phenolic compounds that modify certain characteristics in blended wines, particularly those related to mouthfeel. The aim of this work was to study the effect of Carménère, Merlot and Cabernet Franc on the phenolic composition, proanthocyanidin profile and mouthfeel characteristics of Cabernet Sauvignon blends. Significant differences in chemical composition were observed among the monovarietal wines. Separation using Sep-Pak C₁₈ cartridges revealed differences in the concentration but not in the proportion of various proanthocyanidins. Blending reduced polyphenol concentration differences among the various monovarietal wines. Although no major overall differences were observed after blending the monovarietal wines, this oenological practice produced clear differences in mouthfeel characteristics in such a way that the quality of the perceived astringency was different. This study showed that the use of a particular wine variety (Cabernet Sauvignon) in a higher proportion in wine blending produced blends that were less differentiable from the monovarietal wine, owing to a suppression effect, producing an apparent standardization of the wines regarding chemical composition. © 2013 Society of Chemical Industry.

Intrinsically safe moisture blending system

Science.gov (United States)

Hallman Jr., Russell L.; Vanatta, Paul D.

2012-09-11

A system for providing an adjustable blend of fluids to an application process is disclosed. The system uses a source of a first fluid flowing through at least one tube that is permeable to a second fluid and that is disposed in a source of the second fluid to provide the adjustable blend. The temperature of the second fluid is not regulated, and at least one calibration curve is used to predict the volumetric mixture ratio of the second fluid with the first fluid from the permeable tube. The system typically includes a differential pressure valve and a backpressure control valve to set the flow rate through the system.

On technology blending.

OpenAIRE

Rosenberg N

1986-01-01

ILO pub-WEP pub. Working paper on the blending of traditional technology and technological change in developing countries - argues that choice of technology should be compatible with labour intensive requirements and local level management and economic conditions; considers employment creation and economic implications; concludes that technology transfer should be selective. References.

Judicial review of administrative silence

Directory of Open Access Journals (Sweden)

Radošević Ratko S.

2015-01-01

Full Text Available Administrative silence is a situation in which the competent authority, within the statutory deadline, has not issued an administrative act at the request of the party. In the case of administrative silence, given the fact that the citizens are unable to protect their rights and legal interests without an administrative act, they are provided with legal protection. In this case, the same legal relationship is created, directly on the basis of the statute, as in the situation in which the party's request is rejected. This means that the party may, under the conditions prescribed by the statute, initiate the procedure of judicial review of administrative silence. In the paper, the author explains the conditions under which the judicial review of administrative silence can be initiated and the role of the court in this judicial procedure.

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

International Nuclear Information System (INIS)

Yehia, A.A.; El Elnashar, D.

2005-01-01

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

Assessment of oral safety profile of aqueous extract blend of three ...

African Journals Online (AJOL)

... did not reveal any pathological changes attributable to treatment with the spice blend extract. Conclusions: These findings indicate that oral consumption of a spice blend of garlic, ginger and cayenne pepper in humans may be safe. Keywords: Spice blend, Toxicity, Histology, Marker enzymes, Medicinal, Safety profile ...

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

Directory of Open Access Journals (Sweden)

Hassan Rastegarpour

2011-04-01

Full Text Available 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- mixing a traditional classroom environment with online components – but is it actually effective? However, with the explosion of blended course delivery in recent years- despite the lack of research in this area- educational institution and corporate training take this position for granted. This study explores capabilities of blended learning and its impact on the future of learning environments. Particular focus in this article is given to the role of affective domain in face to face learning, and how to design a blend.

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.

How Materials Support Conceptual Blending in Ideation

DEFF Research Database (Denmark)

Biskjaer, Michael Mose; Fischel, Aron Daniel; Dove, Graham

2018-01-01

as an explanatory model to pry open the complexity of this activity, showing how research on design materials improves insight into how a design concept emerges. We show this empirically in a second-by- second analysis of a card-based design ideation episode using a multi-touch surface table. We offer process......-analytical evidence for the case that manipulation of design materials helps stabilize an emerging concept, as conceptual blending research has shown by analyzing artifacts, and extend this work by showing the dynamic interplay between the emerging conceptual blend and participants’ collaborative interaction...... with the materials. Our study advances understanding of interaction with materials in design ideation and aims to facilitate future research on how materials support conceptual blending as a useful model of how design concepts emerge....

High performance lignin-acrylonitrile polymer blend materials

Energy Technology Data Exchange (ETDEWEB)

Naskar, Amit K.; Tran, Chau D.

2017-11-14

A polymer blend material comprising: (i) a lignin component having a weight-average molecular weight of up to 1,000,000 g/mol; and (ii) an acrylonitrile-containing copolymer rubber component comprising acrylonitrile units in combination with diene monomer units, and having an acrylonitrile content of at least 20 mol %; wherein said lignin component is present in an amount of at least 5 wt % and up to about 95 wt % by total weight of components (i) and (ii); and said polymer blend material possesses a tensile yield stress of at least 5 MPa, or a tensile stress of at least 5 MPa at 10% elongation, or a tensile stress of at least 5 MPa at 100% elongation. Methods for producing the polymer blend, molded forms thereof, and articles thereof, are also described.

Crystallinity evaluation of polyhydroxybutyrate and polycaprolactone blends

International Nuclear Information System (INIS)

Cavalcante, Maxwell P.; Rodrigues, Elton Jorge R.; Tavares, Maria Ines B.

2015-01-01

Polyhydroxybutyrate, PHB, is a polymer obtained through bacterial or synthetic pathways. It has been used in the biomedical field as a matrix for drug delivery, medical implants and as scaffold material for tissue engineering. PHB has high structural organization, which makes it highly crystalline and brittle, making biodegradation difficult, reducing its employability. In order to enhance the mechanical and biological properties of PHB, blends with other polymers, biocompatible or not, are researched and produced. In this regard, blends of PHB and polycaprolactone, PCL, another biopolymer widely used in the biomedical industry, were obtained via solution casting and were characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and low field nuclear magnetic resonance (LF-NMR). Results have shown a dependence between PHB's crystallinity index and PCL quantity employed to obtain the blends.(author)

Experimental investigation on CRDI engine using butanol-biodiesel-diesel blends as fuel

Science.gov (United States)

Divakar Shetty, A. S.; Dineshkumar, L.; Koundinya, Sandeep; Mane, Swetha K.

2017-07-01

In this research work an experimental investigation of butanol-biodisel-diesel blends on combustion, performance and emission characteristics of a direct injection (DI) diesel engine is carried out. The blends are prepared at different proportions and fuel properties such as calorific value, viscosity, flash point and fire point, cloud point, pour point of butanol (B), biodiesel (B), diesel (D), biodiesel-diesel (BD) blends and butanol-biodiesel-diesel (BBD) blends are determined. The engine test is conducted at different speed and load. From the results obtained for fuel properties we can observe that the flash, fire and pour point, viscosity and density are decreasing by increasing the percentage of butanol in BBD blends. It is also observed that the performance parameters such as brake thermal efficiency (BTE) and exhaust gas temperature increases with increase in the proportion of butanol in BBD blend. However, the brake specific fuel consumption (BFSC) decreases with increase in the proportion of butanol in BBD blend. The increase of butanol in BBD blends also influence to increase on emission characteristic such as carbon monoxide (CO), hydrocarbon (HC) and oxides of nitrogen (NOx).

A poly(vinyl alcohol)/sodium alginate blend monolith with nanoscale porous structure.

Science.gov (United States)

Sun, Xiaoxia; Uyama, Hiroshi

2013-10-04

A stimuli-responsive poly(vinyl alcohol) (PVA)/sodium alginate (SA) blend monolith with nanoscale porous (mesoporous) structure is successfully fabricated by thermally impacted non-solvent induced phase separation (TINIPS) method. The PVA/SA blend monolith with different SA contents is conveniently fabricated in an aqueous methanol without any templates. The solvent suitable for the fabrication of the present blend monolith by TINIPS is different with that of the PVA monolith. The nanostructural control of the blend monolith is readily achieved by optimizing the fabrication conditions. Brunauer Emmett Teller measurement shows that the obtained blend monolith has a large surface area. Pore size distribution plot for the blend monolith obtained by the non-local density functional theory method reveals the existence of the nanoscale porous structure. Fourier transform infrared analysis reveals the strong interactions between PVA and SA. The pH-responsive property of the blend monolith is investigated on the basis of swelling ratio in different pH solutions. The present blend monolith of biocompatible and biodegradable PVA and SA with nanoscale porous structure has large potential for applications in biomedical and environmental fields.

Characterization of interfaces in Binary and Ternary Polymer Blends by Positron Lifetime Spectroscopy

Science.gov (United States)

Ranganathaiah, C.

2015-06-01

A miscible blend is a single-phase system with compact packing of the polymeric chains/segments due configuration/conformational changes upon blending. Differential Scanning Calorimetry (DSC) is the most employed method to ascertain whether the blend is miscible or immiscible. Positron Lifetime Spectroscopy (PLS) has been employed in recent times to study miscibility properties of polymer blends by monitoring the ortho-Positronium annihilation lifetimes as function of composition. However, just free volume monitoring and the DSC methods fail to provide the composition dependent miscibility of blends. To overcome this limitation, an alternative approach based on hydrodynamic interactions has been developed to derive this information using the same o-Ps lifetime measurements. This has led to the development of a new method of measuring composition dependent miscibility level in binary and ternary polymer blends. Further, the new method also provides interface characteristics for immiscible blends. The interactions between the blend components has a direct bearing on the strength of adhesion at the interface and hence the hydrodynamic interaction. Understanding the characteristic of interfaces which decides the miscibility level of the blend and their end applications is made easy by the present method. The efficacy of the present method is demonstrated for few binary and ternary blends.

Thermal behavior and kinetics of bio-ferment residue/coal blends during co-pyrolysis

International Nuclear Information System (INIS)

Du, Yuying; Jiang, Xuguang; Lv, Guojun; Ma, Xiaojun; Jin, Yuqi; Wang, Fei; Chi, Yong; Yan, Jianhua

2014-01-01

Highlights: • The Activation energy for the blends is lower than that of BR and coal when BR < 50%. • The BR/coal blends start to decompose at approximately 45 °C releasing ammonia. • The yield of gaseous products increases with increasing BR blending ratio. • NH 3 , alkanes and CO 2 increase with increasing BR blending ratio. • Interactions most likely occur between the BR and the coal during co-pyrolysis. - Abstract: In this work, the thermal behavior and kinetics of bio-ferment residue (BR) and coal blends during co-pyrolysis were investigated using TG-FTIR and kinetic analysis. The co-pyrolysis of BR and coal occurred in three major stages. The BR/coal blends lost most of their weight during the devolatilization stage. The kinetics of the BR/coal blends in this stage implied that the activation energy was lower than that of BR and coal below a certain BR blending ratio. The BR/coal blends started to decompose at approximately 45 °C, releasing ammonia followed by alkanes, carbon dioxide, methane and carbon monoxide. The total yield of gaseous products (primarily ammonia, alkanes and carbon dioxide) increased with increasing BR blending ratio. Moreover, interactions most likely occurred between the BR and the coal during co-pyrolysis

River Protection Project Mission Analysis Waste Blending Study

International Nuclear Information System (INIS)

Shuford, D.H.; Stegen, G.

2010-01-01

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.

The Effect of Blended Learning in Mathematics Course

Science.gov (United States)

Lin, Ya-Wen; Tseng, Chih-Lung; Chiang, Po-Jui

2017-01-01

With the advent of the digital age, traditional didactic teaching and online learning have been modified and gradually replaced by "Blended Learning." The purpose of this study was to explore the influences of blended learning pedagogy on junior high school student learning achievement and the students' attitudes toward mathematics. To…

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 shipping...

Blended Learning: Deficits and Prospects in Higher Education

Science.gov (United States)

Cuesta Medina, Liliana

2018-01-01

This article examines the nature and evolution of the term blended learning (BL), which encompasses numerous connotations, including its conception as a strategy, delivery mode, opportunity, educational shift, or pedagogical approach. Although much has been said in this field, very few studies examine the different types of blends behind their…

Crystallization behavior of partially miscible biodegradable poly(butylene succinate)/poly(ethylene succinate) blends

International Nuclear Information System (INIS)

He, Yi-Song; Zeng, Jian-Bing; Li, Shao-Long; Wang, Yu-Zhong

2012-01-01

Graphical abstract: Crystallization rate of PBS in the blends decreased first and then increased with increase in PES content, and that of PES increased steadily with increase in PBS content. The rich component formed a continuous phase and the other formed a dispersed phase of the blend. Crystal structures of PBS and PES were almost unchanged after blending with each other. Highlights: ► PBS/PES blend systems are partially miscible. ► Blending did not change the crystallization mechanisms of PBS and PES not affects the crystallization rates. ► The rich component formed the continuous phase while the poor component formed the dispersed phase of the blends. ► Crystal structures of PBS and PES were almost unchanged after blending with each other. - Abstract: Biodegradable blend of poly(butylene succinate) (PBS) and poly(ethylene succinate) (PES) was prepared by solution blending and casting method with chloroform as a mutual solvent. Miscibility of the blends was investigated by differential scanning calorimetry (DSC). The results indicated that PBS and PES were partially miscible. Crystallization kinetics, crystalline morphology and crystal structure of the blends were studied by DSC, polarized optical microscope (POM), and wide-angle X-ray diffraction (WAXD), respectively. Nonisothermal and isothermal crystallization kinetics suggested that the crystallizability of PBS in the blends decreased first and then increased with increase in PES content, and that of PES increased steadily with increase in PBS content. POM observation illustrated that the rich component formed a continuous phase and the other formed a dispersed phase. The results of WAXD indicated that the crystal structures of PBS and PES were almost unchanged before and after blending, since the positions of characteristic diffraction peaks of both components remain almost unchanged.

Mechanical properties, morphology, and hydrolytic degradation behavior of polylactic acid / natural rubber blends

Science.gov (United States)

Buys, Y. F.; Aznan, A. N. A.; Anuar, H.

2018-01-01

Due to its biodegradability and renewability, polylactic acid (PLA) has been receiving enormous attention as a potential candidate to replace petroleum based polymers. However, PLA has limitation due to its inherent brittleness. In order to overcome this limitation, blending PLA with elastomeric materials such as natural rubber (NR) are commonly reported. In previous, several researches on PLA/NR blend had been reported, with most of them evaluated the mechanical properties. On the other hand, study of degradation behavior is significance of importance, as controlling materials degradation is required in some applications. This research studied the effect of blend composition on mechanical properties, morphology development, and hydrolytic degradation behavior of PLA/NR blends. Various compositions of PLA/NR blends were prepared by melt blending technique. Tensile test and impact test of the blends were performed to evaluate the mechanical properties. Addition of NR improved the elongation at break and impact strength of the blends, but reduced the tensile strength and stiffness of the specimens. Dynamic Mechanical Analysis (DMA) measurements of the blends displayed two peaks at temperature -70˚C which corresponded to T g of NR and 65˚C which corresponded to T g of PLA. Field Emission Scanning Electron Microscopy (FE-SEM) micrograph of 70/30 PLA/NR specimen also showed two distinct phases, which lead to indication that PLA/NR blends are immiscible. Hydrolytic degradation behavior was evaluated by measuring the remaining weight of the samples immersed in sodium hydroxide solution for a predetermined times. It was shown that the degradation behavior of PLA/NR blends is affected by composition of the blends, with 100 PLA and 70/30 PLA/NR blend showed the fastest degradation rate and 100 NR displayed the slowest one.

Blended learning in ethics education: a survey of nursing students.

Science.gov (United States)

Hsu, Li-Ling

2011-05-01

Nurses are experiencing new ethical issues as a result of global developments and changes in health care. With health care becoming increasingly sophisticated, and countries facing challenges of graying population, ethical issues involved in health care are bound to expand in quantity and in depth. Blended learning rather as a combination of multiple delivery media designed to promote meaningful learning. Specifically, this study was focused on two questions: (1) the students' satisfaction and attitudes as members of a scenario-based learning process in a blended learning environment; (2) the relationship between students' satisfaction ratings of nursing ethics course and their attitudes in the blended learning environment. In total, 99 senior undergraduate nursing students currently studying at a public nursing college in Taiwan were invited to participate in this study. A cross-sectional survey design was adopted in this study. The participants were asked to fill out two Likert-scale questionnaire surveys: CAAS (Case Analysis Attitude Scale), and BLSS (Blended Learning Satisfaction Scale). The results showed what students felt about their blended learning experiences - mostly items ranged from 3.27-3.76 (the highest score is 5). Another self-assessment of scenario analysis instrument revealed the mean scores ranged from 2.87-4.19. Nearly 57.8% of the participants rated the course 'extremely helpful' or 'very helpful.' This study showed statistically significant correlations (r=0.43) between students' satisfaction with blended learning and case analysis attitudes. In addition, results testified to a potential of the blended learning model proposed in this study to bridge the gap between students and instructors and the one between students and their peers, which are typical of blended learning, and to create meaningful learning by employing blended pedagogical consideration in the course design. The use of scenario instruction enables students to develop critical

Blending Biodiesel in Fishing Boat Fuels for Improved Fuel Characteristics

International Nuclear Information System (INIS)

Lin, Cherng-Yuan

2014-01-01

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% if 25 wt.% biodiesel is blended. 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 1–4.5%.

Blending Biodiesel in Fishing Boat Fuels for Improved Fuel Characteristics

Energy Technology Data Exchange (ETDEWEB)

Lin, Cherng-Yuan, E-mail: lin7108@ntou.edu.tw [Department of Marine Engineering, National Taiwan Ocean University, Keelung, Taiwan (China)

2014-02-24

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% if 25 wt.% biodiesel is blended. 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 1–4.5%.

Modification of PE/PP Polymer Blend Nanocomposites with EPR and EVA Copolymers

Directory of Open Access Journals (Sweden)

Jelenčić, J.

2010-04-01

Full Text Available During the last decade, the use of polyolephinic polymers has been growing in a wide range of fields of applicability and the most widely used polymers are polyethylene and polypropylene. They can be processed separately to produce items with certain properties as well as in the form of blends, where special combinations of properties and price are intended. As it is known, polyethylene (PE and polypropylene (PP are incompatible and the weak interfacial bond strength between the phases directly linked to the blend morphology and results in poor mechanical properties. The properties of many polymer blends arise from the fine-scale structural arrangements or blend morphologies obtained during processing in addition to the proportion of each polymer type present. Compounding PE/PP blends with a single compatibilizer or their combination or some other additives as nanofiller, results in multi-component composites of great interest to research as they enable simultaneous improvement in the final properties of the blend. In addition, it is well known that the extrusion process has a significant effect on the dispersion of the filler in the blends. In this work, the mutual effect of the nanofiller silicium-dioxide (SiO2 and the compatibilizers ethylene-propylene copolymer (EPR and ethylene-vinyl acetate copolymer (EVA on the properties of blends based on polyethylene and polypropylene were studied. The morphology of the samples prepared with nanofiller and compatibilizers is much finer in comparison to the virgin blend. Better dispersion of nanofiller will result in better stability of the polymer blend and decrease in polymer flammability. The addition of the nanofiller and compatibilizers produced an increase in the elasticity especially for the samples prepared in the two-stage extrusion process where the nanofiller was first extruded with PE matrix and then with other polymers of the blends. SEM micrographs confirm finer morphology of samples

Miscibility phase diagram of ring-polymer blends: A topological effect.

Science.gov (United States)

Sakaue, Takahiro; Nakajima, Chihiro H

2016-04-01

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 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 ring-ring polymer blends. Scaling formulas for the shift of critical point for both cases are derived. We discuss the valid range of the present theory, and the crossover to the linear polymer blends behaviors, which is expected for short chains. These analyses put forward a view that the topological constraints could be represented as an effective excluded-volume effects, in which the topological length plays a role of the screening factor.

Preparation and characterization of collagen/hydroxypropyl methylcellulose (HPMC) blend film.

Science.gov (United States)

Ding, Cuicui; Zhang, Min; Li, Guoying

2015-03-30

This study aimed to prepare and characterize the collagen/HPMC blend film (1/1). Thermogravimetric analysis and differential scanning calorimetry were used to investigate the thermal properties of the film. Both thermal decomposition temperature and denaturation temperature of the blend film were higher than those of the collagen film due to the intermolecular hydrogen bonding interaction between collagen and HPMC, which was demonstrated by Fourier transform infrared spectroscopy. Additionally, the morphologies, mechanical properties and hydrophilicity of films were examined. The blend film exhibited a more homogeneous and compact structure compared with that of the collagen film, as observed from scanning electron microscopy and atomic force microscopy. The tensile strength, ultimate elongation and hydrophilicity of the blend film were superior to those of the pure collagen film. Furthermore, the introduction of polyethylene glycol 1500 had almost no influence on the thermal properties of the blend film but obviously improved its stretch-ability and smoothness. Copyright © 2014 Elsevier Ltd. All rights reserved.

MOOC Blended learning ontwikkelen

NARCIS (Netherlands)

Verjans, Steven

2015-01-01

Presentatie over het ontwerpen van leeractiviteiten (learning design) tijdens de zesde live sessie van de MOOC Blended learning ontwikkelen. Met gebruikmaking van presentatiematerialen van Diana Laurillard, Grainne Conole, Helen Beetham, Jos Fransen, Pieter Swager, Helen Keegan, Corinne Weisgerber.

Blended learning as an effective pedagogical paradigm for biomedical science

OpenAIRE

Perry Hartfield

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...

Chemical Processing of Non-Crop Plants for Jet Fuel Blends Production

Science.gov (United States)

Kulis, M. J.; Hepp, A. F.; McDowell, M.; Ribita, D.

2009-01-01

The use of Biofuels has been gaining in popularity over the past few years due to their ability to reduce the dependence on fossil fuels. Biofuels as a renewable energy source can be a viable option for sustaining long-term energy needs if they are managed efficiently. We describe our initial efforts to exploit algae, halophytes and other non-crop plants to produce synthetics for fuel blends that can potentially be used as fuels for aviation and non-aerospace applications. Our efforts have been dedicated to crafting efficient extraction and refining processes in order to extract constituents from the plant materials with the ultimate goal of determining the feasibility of producing biomass-based jet fuel from the refined extract. Two extraction methods have been developed based on communition processes, and liquid-solid extraction techniques. Refining procedures such as chlorophyll removal and transesterification of triglycerides have been performed. Gas chromatography in tandem with mass spectroscopy is currently being utilized in order to qualitatively determine the individual components of the refined extract. We also briefly discuss and compare alternative methods to extract fuel-blending agents from alternative biofuels sources.

KOREA'S BLENDED LEARNING IN NURSING: ISSUES AND THE WAY FORWARD

Directory of Open Access Journals (Sweden)

Claire Su-Yeon Park

2017-01-01

Full Text Available Blended learning is receiving significant scholarly attention in Korean nursing education for a number of reasons: the downsizing of universities due to low birth rates; the high demand for nurses in a super-aged society; and nursing’s distinctive characteristics, i.e., theory-driven practical scholarship (Park, 2016. However, the lack of scholarly evidence on this subject suggests that current nursing scholarship is not satisfying the needs of the times. This article thus addressed problems in the current literature on Korea’s blended learning in nursing and suggested a way forward for the future. A rigorous literature review and synthesis were conducted from July 01 to August 10, 2016 using an electronic database operated by Korea Education & Research Information Service. The key words were “blended learning” and “nursing.” The search result included twelve publications on “blended learning” and “nursing” in Korea and thirty publications on “blended learning” and “nursing” in other countries. All articles were first scrutinized by the author for relevance to blended learning in nursing and were then compared and synthesized. Korean articles had straight research structures from central casting in contrast to the articles from other countries. Specifically, these structures included 1 an ambiguous definition of the scope of blended learning: i.e., multiple instructional methods or delivery media, rather than an integration of technology-mediated instruction into a face-to-face (F2F learning environment (Bonk & Graham, 2005; “enhancing blends[1]” rather than “enabling blends” or “transforming blends” (Bonk & Graham, 2005, see Table 1: Different categories of blended learning systems, 2 a very small sample size with a limited location, 3 the use of very basic descriptive statistical analyses, 4 undifferentiated types of a blended learning: i.e., most articles referred to blended learning in nursing

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.

Biomimetic, bioactive etheric polyphosphazene-poly(lactide-co-glycolide) blends for bone tissue engineering.

Science.gov (United States)

Deng, Meng; Nair, Lakshmi S; Nukavarapu, Syam P; Kumbar, Sangamesh G; Brown, Justin L; Krogman, Nicholas R; Weikel, Arlin L; Allcock, Harry R; Laurencin, Cato T

2010-01-01

The long-term goal of this work is to develop biomimetic polymer-based systems for bone regeneration that both allow for neutral pH degradation products and have the ability to nucleate bonelike apatite. In this study, the etheric biodegradable polyphosphazene, poly[(50%ethyl glycinato)(50%methoxyethoxyethoxy)phosphazene] (PNEG(50)MEEP(50)) was blended with poly(lactide-co-glycolide) PLAGA and studied their ability to produce high-strength degradable biomaterials with bioactivity. Accordingly, two blends with weight ratios of PNEG(50)MEEP(50) to PLAGA 25:75 (BLEND25) and 50:50 (BLEND50) were fabricated using a mutual solvent approach. Increases in PNEG(50)MEEP(50) content in the blend system resulted in decreased elastic modulus of 779 MPa when compared with 1684 MPa (PLAGA) as well as tensile strength 7.9 MPa when compared with 25.7 MPa (PLAGA). However, the higher PNEG(50)MEEP(50) content in the blend system resulted in higher Ca/P atomic ratio of the apatite layer 1.35 (BLEND50) when compared with 0.69 (BLEND25) indicating improved biomimicry. Furthermore, these blends supported primary rat osteoblast adhesion and proliferation with an enhanced phenotypic expression when compared with PLAGA. These findings establish the suitability of PNEG(50)MEEP(50)-PLAGA biodegradable blends as promising bioactive materials for orthopedic applications.

Understanding constraint release in star/linear polymer blends

KAUST Repository

Shivokhin, M. E.

2014-04-08

In this paper, we exploit the stochastic slip-spring model to quantitatively predict the stress relaxation dynamics of star/linear blends with well-separated longest relaxation times and we analyze the results to assess the validity limits of the two main models describing the corresponding relaxation mechanisms within the framework of the tube picture (Doi\\'s tube dilation and Viovy\\'s constraint release by Rouse motions of the tube). Our main objective is to understand and model the stress relaxation function of the star component in the blend. To this end, we divide its relaxation function into three zones, each of them corresponding to a different dominating relaxation mechanism. After the initial fast Rouse motions, relaxation of the star is dominated at intermediate times by the "skinny" tube (made by all topological constraints) followed by exploration of the "fat" tube (made by long-lived obstacles only). At longer times, the tube dilation picture provides the right shape for the relaxation of the stars. However, the effect of short linear chains results in time-shift factors that have never been described before. On the basis of the analysis of the different friction coefficients involved in the relaxation of the star chains, we propose an equation predicting these time-shift factors. This allows us to develop an analytical equation combining all relaxation zones, which is verified by comparison with simulation results. © 2014 American Chemical Society.

Engineered Option Treatment of Remediated Nitrate Salts: Surrogate Batch-Blending Testing

Energy Technology Data Exchange (ETDEWEB)

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

2016-03-11

This report provides results from batch-blending test work for remediated nitrate salt (RNS) treatment. Batch blending was identified as a preferred option for blending RNS and unremediated nitrate salt (UNS) material with zeolite to effectively safe the salt/Swheat material identified as ignitable (U.S. Environmental Protection Agency code D001). Blending with zeolite was the preferred remediation option identified in the Options Assessment Report and was originally proposed as the best option for remediation by Clark and Funk in their report, Chemical Reactivity and Recommended Remediation Strategy for Los Alamos Remediated Nitrate Salt (RNS) Wastes, and also found to be a preferred option in the Engineering Options Assessment Report: Nitrate Salt Waste Stream Processing. This test work evaluated equipment and recipe alternatives to achieve effective blending of surrogate waste with zeolite.

NUCLEAR ISOTOPIC DILUTION OF HIGHLY ENRICHED URANIUM BY DRY BLENDING VIA THE RM-2 MILL TECHNOLOGY

International Nuclear Information System (INIS)

Rajamani, Raj K.; Latchireddi, Sanjeeva; Devrani, Vikas; Sethi, Harappan; Henry, Roger; Chipman, Nate

2003-01-01

DOE has initiated numerous activities to focus on identifying material management strategies to disposition various excess fissile materials. In particular the INEEL has stored 1,700 Kg of offspec HEU at INTEC in CPP-651 vault facility. Currently, the proposed strategies for dispositioning are (a) aqueous dissolution and down blending to LEU via facilities at SRS followed by shipment of the liquid LEU to NFS for fabrication into LWR fuel for the TVA reactors and (b) dilution of the HEU to 0.9% for discard as a waste stream that would no longer have a criticality or proliferation risk without being processed through some type of enrichment system. Dispositioning this inventory as a waste stream via aqueous processing at SRS has been determined to be too costly. Thus, dry blending is the only proposed disposal process for the uranium oxide materials in the CPP-651 vault. Isotopic dilution of HEU to typically less than 20% by dry blending is the key to solving the dispositioning issue (i.e., proliferation) posed by HEU stored at INEEL. RM-2 mill is a technology developed and successfully tested for producing ultra-fine particles by dry grinding. Grinding action in RM-2 mill produces a two million-fold increase in the number of particles being blended in a centrifugal field. In a previous study, the concept of achieving complete and adequate blending and mixing (i.e., no methods were identified to easily separate and concentrate one titanium compound from the other) in remarkably short processing times was successfully tested with surrogate materials (titanium dioxide and titanium mono-oxide) with different particle sizes, hardness and densities. In the current project, the RM-2 milling technology was thoroughly tested with mixtures of natural uranium oxide (NU) and depleted uranium oxide (DU) stock to prove its performance. The effects of mill operating and design variables on the blending of NU/DU oxides were evaluated. First, NU and DU both made of the same oxide

Preparation and Characterization of Blended Films from Quaternized Hemicelluloses and Carboxymethyl Cellulose

Directory of Open Access Journals (Sweden)

Xian-Ming Qi

2015-12-01

Full Text Available Utilization of hemicelluloses from biomass energy is an important approach to explore renewable resources. A convenient, quick, and inexpensive method for the preparation of blended films from quaternized hemicelluloses (QH and carboxymethyl cellulose (CMC was introduced into this study. QH and CMC solution were first mixed to form homogeneous suspension, and then were dried under vacuum to fabricate the blended films. The FT-IR and XRD results indicated that the linkage between QH and CMC was due to the hydrogen bonding and electrostatic interaction. From the results of mechanical properties and water vapor permeability (WVP, the tensile strength of the blended films increased with the QH/CMC content ratio increasing in appropriate range, and the WVP of the blended films decreased. The maximum value of tensile strength of blend film achieved was 27.4 MPa. In addition, the transmittances of the blended films increased with the decreasing of QH/CMC content ratio. When the weight ratio (QH: CMC was 1:1.5, the blend film showed the best light transmittance (45%. All the results suggested that the blended films could be used in areas of application in the coating and packaging fields from the good tensile strength, transmittance, and low WVP.

Preparation and Characterization of Blended Films from Quaternized Hemicelluloses and Carboxymethyl Cellulose

Science.gov (United States)

Qi, Xian-Ming; Liu, Shi-Yun; Chu, Fang-Bing; Pang, Shuai; Liang, Yan-Ru; Guan, Ying; Peng, Feng; Sun, Run-Cang

2015-01-01

Utilization of hemicelluloses from biomass energy is an important approach to explore renewable resources. A convenient, quick, and inexpensive method for the preparation of blended films from quaternized hemicelluloses (QH) and carboxymethyl cellulose (CMC) was introduced into this study. QH and CMC solution were first mixed to form homogeneous suspension, and then were dried under vacuum to fabricate the blended films. The FT-IR and XRD results indicated that the linkage between QH and CMC was due to the hydrogen bonding and electrostatic interaction. From the results of mechanical properties and water vapor permeability (WVP), the tensile strength of the blended films increased with the QH/CMC content ratio increasing in appropriate range, and the WVP of the blended films decreased. The maximum value of tensile strength of blend film achieved was 27.4 MPa. In addition, the transmittances of the blended films increased with the decreasing of QH/CMC content ratio. When the weight ratio (QH: CMC) was 1:1.5, the blend film showed the best light transmittance (45%). All the results suggested that the blended films could be used in areas of application in the coating and packaging fields from the good tensile strength, transmittance, and low WVP. PMID:28787804

Modelling of NO formation in the combustion of coal blends

Energy Technology Data Exchange (ETDEWEB)

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

2002-03-01

Coal blending is becoming of increasing importance in power stations firing pulverised coal as a result of increasing competition, stricter emission legislation and is an attractive way of improving plant economic and combustion performance. Presently, the two general methods used by power station operators to assess or predict the performance of an unknown coal blend to be fired in power station boilers are by the use of experimental large scale rig tests or correlation indices derived from experience of firing other coal blends in the power station environment. The first is expensive and the second is of doubtful accuracy in some cases. This paper evaluates the application of mathematical modelling of the combustion of a series of binary coal blends in the test situation of a drop tube reactor to predict the NO emissions and degree of char burnout. Its applicability to low NOx burners used in power stations is discussed and it is concluded that present mathematical coal combustion models are not developed sufficiently to enable an adequate description of the binary blends and the physical and chemical processes, which may include interactions, during combustion of the blend. This means that accurate predictions cannot be made. 20 refs., 4 figs., 5 tabs.

Impact of ternary blends of biodiesel on diesel engine performance

Directory of Open Access Journals (Sweden)

Prem Kumar

2016-06-01

Full Text Available The Pongamia and waste cooking oils are the main non edible oils for biodiesel production in India. The aim of the present work is to evaluate the fuel properties and investigate the impact on engine performance using Pongamia and waste cooking biodiesel and their ternary blend with diesel. The investigation of the fuel properties shows that Pongamia biodiesel and waste cooking biodiesel have poor cold flow property. This will lead to starting problem in the engine operation. To overcome this problem the ternary blends of diesel, waste cooking biodiesel and Pongamia biodiesel are prepared. The cloud and pour point for ternary blend, (WCB20:PB20:D60 were found to be 7 °C and 6.5 °C which are comparable to cloud and pour point of diesel 6 °C and 5 °C, respectively. The result of the test showed that brake specific fuel consumption for Pongamia biodiesel and waste cooking biodiesel is higher than ternary blend, (WCB20:PB20:D60 due to their lower energy content. The brake thermal efficiency of ternary blend and diesel is comparable while the Pongamia and waste cooking biodiesel have low efficiency. The result of investigation showed that ternary blend can be developed as alternate fuel.

Fabrication and Characterization of Electrospun Wool Keratin/Poly(vinyl alcohol Blend Nanofibers

Directory of Open Access Journals (Sweden)

Shuai Li

2014-01-01

Full Text Available Wool keratin/poly(vinyl alcohol (PVA blend nanofibers were fabricated using the electrospinning method in formic acid solutions with different weight ratios of keratin to PVA. The resultant blend nanofibers were characterized by scanning electron microscopy (SEM, Fourier transform infrared (FTIR, X-ray diffraction (XRD, thermal gravimetric analysis (TGA, and tensile test. SEM images showed that the diameter of the blend nanofibers was affected by the content of keratin in blend solution. FTIR and XRD analyses data demonstrated that there were good interactions between keratin and PVA in the blended nanofibers caused by possibly hydrogen bonds. The TGA study revealed that the thermal stability of the blend nanofibers was between those of keratin and PVA. Tensile test indicated that the addition of PVA was able to improve the mechanical properties of the electrospun nanofibers.

Discernment of synergism in pyrolysis of biomass blends using thermogravimetric analysis.

Science.gov (United States)

Mallick, Debarshi; Poddar, Maneesh Kumar; Mahanta, Pinakeswar; Moholkar, Vijayanand S

2018-04-12

This study reports pyrolysis kinetics of biomass blends using isoconversional methods, viz. Friedman, FWO and KAS. Blends of three biomasses, viz. saw dust, bamboo dust and rice husk, were used. Extractives and volatiles in biomass and minerals in ash had marked influence on enhancement of reaction kinetics during co-pyrolysis, as indicated by reduction in activation energy and increase in decomposition intensity. Pyrolysis kinetics of saw dust and rice husk accelerated (positive synergy), while that of bamboo dust decelerated after blending (negative synergy). Predominant reaction mechanism of all biomass blends was 3-D diffusion in lower conversion range (α ≤ 0.5), while for α ≥ 0.5 pyrolysis followed random nucleation (or nucleation and growth mechanism). Higher reaction order for pyrolysis of blends of rice husk with saw dust and bamboo dust was attributed to catalytic effect of minerals in ash. Positive ΔH and ΔG was obtained for pyrolysis of all biomass blends. Copyright © 2018 Elsevier Ltd. All rights reserved.

Cure and mechanical behaviors of cycloaliphatic/DGEBA epoxy blend system using electron-beam technique

Energy Technology Data Exchange (ETDEWEB)

Lee, J.R.; Heo, G.Y.; Park, S.J. [Korea Research Institute of Chemical Technology, Taejeon (Korea)

2002-05-01

4-Vinyl-1- cyclohexene diepoxide (VCE)/ diglycidyl ether of bisphenol -A(DGEBA) epoxy blends with benzylquinoxalinium hexafluoroanti-monate were cured using an electron-beam technique. the effect of DGEBA content to VCE on cure behavior, thermal stabilities, and mechanical properties was investigated. The composition of VCE/DGEBA blend system varied within 100:0, 80:20, 60:40. 40:60 20:80, and 0:100wt%. The cure behavior and thermal stability of the cured specimens was monited by near-infrared spectroscopy and thermogravimetric analysis, respectively. Also, the critical stress intensity factor (K{sub 1C}) test of the cured specimens was performed to study the mechanical interfacial properties. As a result, the decreases of short side-chide structure and chain scission were observed in NIR measurements as the DGEBA content increases, resulting in varying the hydroxyl and carbonyl groups. And, the initial decomposition temperature (IDT), temperature of maximum weight loss (T{sub max}), and decomposition activation energy (E{sub d}) as thermal stability factors were increased with increasing the DGEBA content. These results could be explained by mean of decreasing viscosity, stable aromatic ring structure, and grafted interpenetrating polymer network with increasing of DGEBA content. Also, the maximum K{sub 1C} value showed at mixing ratio of 40:60 wt% in this blend system. (author). 22 refs., 2 tabs., 6 figs.

Fabrication and Characterization of Electrospun Wool Keratin/Poly(vinyl alcohol) Blend Nanofibers

OpenAIRE

Shuai Li; Xu-Hong Yang

2014-01-01

Wool keratin/poly(vinyl alcohol) (PVA) blend nanofibers were fabricated using the electrospinning method in formic acid solutions with different weight ratios of keratin to PVA. The resultant blend nanofibers were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), and tensile test. SEM images showed that the diameter of the blend nanofibers was affected by the content of keratin in blend solution...

A Study of the Use of Jatropha Oil Blends in Boilers

Energy Technology Data Exchange (ETDEWEB)

Krishna, C.R.

2010-10-01

Executive Summary: This project investigated the combustion performance of blends of unrefined Jatropha oil and its blends in laboratory boilers. Although a very limited amount of testing blends in distillate oil, ASTM No. 2 oil or heating oil was conducted, the primary interest was in testing the performance of blends with residual ASTM No. 6 oil. The basic idea is to provide a renewable fuel option to residual oil used in space heating and in industrial applications. The intent also was to explore the use of non-edible plant oil and one that might be potentially cheaper than biodiesel. The characteristics of No. 6 oil, such as high viscosity at ambient temperature, which requires it to be kept heated, make the blending with such oils feasible. Jatropha oil is one such oil and there is currently considerable interest building up in its use as a source for making biodiesel and jet fuel. A 10% blend of Jatropha oil with heating oil was burned using a standard burner in a residential boiler. Combustion performance was shown to be comparable with that of burning heating oil by itself with some noticeable differences. Typical heating oil has about 2000 ppm of sulfur, while the Jatropha oil has about 50 ppm leading to lower levels of sulphur dioxide emissions. Stack measurements also showed that the NOx emission was lower with the blend. We have previously reported similar reductions in NOx with blends of biodiesel in heating oil as well as slight reductions in PM2.5, particulates below 2.5 microns in size. Long term tests were not part of this project and hence deleterious effects on pumps, seals etc., if any, were not measured. The majority of the work involved testing blends of Jatropha oil with residual oil in a 1.5 million Btu/hr boiler with a burner modified to burn residual oil. Blends of 20 and 60% Jatropha oil and 100% Jatropha oil were burned in the combustion performance tests. The residual oil used had a sulfur content of over 2000 ppm and hence dramatic

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...

Effect of reactive agent and transesterification catalyst on properties of PLA/PBAT blends

International Nuclear Information System (INIS)

Pitivut, S; Suttiruengwong, S; Seadan, M

2015-01-01

This research aimed to study the properties of poly (lactic acid) (PLA)/poly (butylene adipate-co-terephthalate) (PBAT) blends with two different reactive systems: free radical reaction through peroxide (Perkadox) and transesterification catalyst (tetrabutyl titanate; TBT). Two blends composed of PLA as a matrix phase with the composition of 80 and 70 percent by weight. PLA/PBAT blends with Perkadox were prepared in twin screw extruder, whereas PLA/PBAT blends with TBT were prepared in an internal mixer. The morphology of the blends was investigated by scanning electron microscope (SEM). Tensile and impact testingsof the blends were reported. In case of the blends with Perkadox, SEM micrographs revealed that the size of particles was substantially reduced when adding more Perkadox. Young's modulus and the tensile strength of all blend ratios were insignificantly changed, whereas the elongation at break was decreased when compared to non-reactive blends due to the possible crosslinking reaction as observed from melt flow index (MFI) values. When adding Perkadox, the impact strength of PLA/PBAT (80/20) remained almost unchanged. However, the impact strength of PLA/PBAT (70/30) was enhanced, increasing to 110% for 0.05 phr Perkadox. In case of the blends with TBT, SEM micrographs showed the decrease in the particle size of PBAT phase when adding TBT. Young's modulus and the tensile strength of all blend ratios were not different, but the elongation at break was improved when adding TBT owing to the transesterification reaction. For PLA/PBAT (80/20), the elongation at break was increased by 39%, whereas the elongation at break was increased by 15% for PLA/PLA (70/30). The impact strength of all blend ratios unaffected. (paper)

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...

Blending of Radioactive Salt Solutions in Million Gallon Tanks - 13002

International Nuclear Information System (INIS)

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

2013-01-01

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. (authors)

Blending of Radioactive Salt Solutions in Million Gallon Tanks - 13002

Energy Technology Data Exchange (ETDEWEB)

Leishear, Robert A.; Lee, Si Y.; Fowley, Mark D.; Poirier, Michael R. [Savannah River National Laboratory, Aiken. S.C., 29808 (United States)

2013-07-01

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. (authors)

Morphology Formation in PC/ABS Blends during Thermal Processing and the Effect of the Viscosity Ratio of Blend Partners

Directory of Open Access Journals (Sweden)

Stefanie Bärwinkel

2016-08-01

Full Text Available Morphology formation during compounding, as well as injection molding of blends containing 60 wt % polycarbonate (PC and 40 wt % polybutadiene rubber-modified styrene-acrylonitrile copolymers (ABS, has been investigated by transmission electron microscopy (TEM. Profiles of the blend morphology have been recorded in injection-molded specimens and significant morphology gradients observed between their skin and core. A <10 µm thick surface layer with strongly dispersed and elongated nano-scale (streak-like styrene acrylonitrile (SAN phases and well-dispersed, isolated SAN-grafted polybutadiene rubber particles is followed by a 50–150 µm thick skin layer in which polymer morphology is characterized by lamellar SAN/ABS phases. Thickness of these lamellae increases with the distance from the specimen’s surface. In the core of the specimens the SAN-grafted polybutadiene rubber particles are exclusively present within the SAN phases, which exhibit a much coarser and less oriented, dispersed morphology compared to the skin. The effects of the viscosity of the SAN in the PC/ABS blends on phase morphologies and correlations with fracture mechanics in tensile and impact tests were investigated, including scanning electron microscopy (SEM assessment of the fracture surfaces. A model explaining the mechanisms of morphology formation during injection molding of PC/ABS blends is discussed.