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.

Positron Lifetime as a Nano probe for Free Volume in Microbial Poly(3- Hydroxybutyrate/ Polymethylmethacrylate) Blends

International Nuclear Information System (INIS)

Abdel-Hady, E.E.; Abdel-El-Latif, R.M.; Mohamed, S.S.

2009-01-01

Poly(β-hydroxybutyrate) PHB is a bio technologically produced polyesters, highly crystalline, totally biodegradable with low versatility in mechanical properties. To overcome this problem it is performed a reactive blending producer with a glassy acrylic polymer, Poly(methylmethacrylate) (PMMA) with different concentrations. positron annihilation lifetime (PAL) spectroscopy has been used to study the effect of PMMA concentrations on the free volume hole properties of PHB. PAL spectra were analyzed using PALSF it program into three components which reflected three different morphologies of the polymer structure. The ortho positronium (ο-Ps) parameters revealed an inflection at (75/25 wt/wt) PHB/PMMA blend. Pure PHB and (75/25 wt/wt) PHB/PMMA blend have been measured as a function of temperature from -30 degree C to 90 degree C. The data clearly revealed the glass transition temperature (T g ) at zero degree C. An attempt is done to find a correlation between the electrical properties of PHB with different concentrations of PMMA and the positron annihilation parameters.

Comparative analysis of the Performance and Emission Characteristics of ethanol-butanol-gasoline blends

Science.gov (United States)

Taneja, Sumit; Singh, Perminderjit, Dr; Singh, Gurtej

2018-02-01

Global warming and energy security being the global problems have shifted the focus of researchers on the renewable sources of energy which could replace petroleum products partially or as a whole. Ethanol and butanol are renewable sources of energy which can be produced through fermentation of biomass. A lot of research has already been done to develop suitable ethanol-gasoline blends. In contrast very little literature available on the butanol-gasoline blends. This research focuses on the comparison of ethanol-gasoline fuels with butanol-gasoline fuels with regard to the emission and performance in an SI engine. Experiments were conducted on a variable compression ratio SI engine at 1600 rpm and compression ratio 8. The experiments involved the measurement of carbon monoxide, carbon dioxide, oxides of nitrogen and unburned hydrocarbons emission and among performance parameters brake specific fuel consumption and brake thermal efficiency were recorded at three loads of 2.5kgs (25%), 5kgs (50%) and 7.5kgs (75%). Results show that ethanol and butanol content in gasoline have decreased brake specific fuel consumption, carbon monoxide and unburned hydrocarbon emissions while the brake thermal efficiency and oxides of nitrogen are increased. Results indicate thatbutanol-gasoline blends have improved brake specific fuel consumption, carbon monoxide emissions in an SI engine as compared to ethanol-gasoline blends. The carbon dioxide emissions and brake thermal efficiencies are comparable for ethanol-gasoline blends and butanol-gasoline blends. The butanol content has a more adverse effect on emissions of oxides of nitrogen than ethanol.

Barrier, structural and mechanical properties of bovine gelatin-chitosan blend films related to biopolymer interactions.

Science.gov (United States)

Benbettaïeb, Nasreddine; Kurek, Mia; Bornaz, Salwa; Debeaufort, Frédéric

2014-09-01

The increased use of synthetic packaging films has led to a high ecological problem due to their total non-biodegradability. Thus, there is a vital need to develop renewable and environmentally friendly bio-based polymeric materials. Films and coatings made from polysaccharide polymers, particularly chitosans and gelatins have good gas barrier properties and are envisaged more and more for applications in the biomedical and food fields, as well as for packaging. In this study a casting method was used to develop an edible plasticised film from chitosan and gelatin. Aiming to develop a blend film with enhanced properties, the effects of mixing chitosan (CS) and gelatin (G) in different proportions (CS:G, 75:25, 50:50, 25:75, w/w) on functional and physico-chemical properties have been studied. Mean film thickness increased linearly (R2 =0.999) with surface density of the film forming solution. An enhancement of mechanical properties by increasing the tensile strength (38.7±11 MPa for pure chitosan and 76.8±9 MPa for pure gelatin film) was also observed in blends, due to gelatin content.When the gelatin content in blend filmswas increased an improvement of both water vapour barrier properties [(4±0.3)×10(-10) g m(-1) s(-1) Pa(-1) for pure chitosan and (2.5±0.14)×10(-10) g m(-1) s(-1) Pa(-1) for pure gelatin, at 70% RH gradient] and oxygen barrier properties ((822.62±90.24)×10(-12) g m(-1) s(-1) Pa(-1) for blend film chitosan:gelatin (25:75 w/w) and (296.67±18.76)×10(-12) g m(-1) s(-1) Pa(-1) for pure gelatin was observed. Fourier transform infrared spectra of blend films showed a shift in the peak positions related to the amide groups (amide-I and amide-III) indicating interactions between biopolymers. Addition of gelatin in chitosan induced greater functional properties (mechanical, barrier) due to chemical interactions, suggesting an inter-penetrated network. © 2014 Society of Chemical Industry.

Comparative performance of direct injection diesel engine operating on ethanol, petrol and rapeseed oil blends

International Nuclear Information System (INIS)

Labeckas, Gvidonas; Slavinskas, Stasys

2009-01-01

This article presents the bench testing results of a four stroke, four cylinder, direct injection, unmodified, diesel engine operating on pure rapeseed oil (RO) and its 2.5 vol%, 5 vol%, 7.5 vol% and 10 vol% blends with ethanol (ERO), petrol (PRO) and both improving agents applied in equal proportions as 50:50 vol% (EPRO). The purpose of the research is to examine the effect of ethanol and petrol addition into RO on the biofuel kinematical viscosity, brake mean effective pressure (bmep), brake specific fuel consumption (bsfc) of a diesel engine and its brake thermal efficiency (bte). Addition into RO from 2.5 to 7.5 vol% of ethanol and petrol its viscosity at ambient temperature of 20 deg. C diminishes by 9.2-28.3% and 14.1-31.7%, respectively. Heating up to the temperature of 60 deg. C the viscosity of pure RO, blends ERO2.5-7.5 and PRO2.5-10 further diminishes 4.2, 3.9-3.8 and 3.9-3.6 times. At 1800 min -1 speed, the maximum brake mean effective pressure (bmep) higher up to 1.6% comparing with that of pure RO (0.77 MPa) ensure three agent blends EPRO5-7.5, whereas at rated 2200 min -1 speed, the bmep higher by 5.6% can be obtained when fuelling the engine with blend PRO2.5. Brake specific fuel consumption (bsfc) at maximum torque (240.2 g/kWh) and rated power (234.0 g/kWh) is correspondingly lower by 3.4% and 5.5% in comparison with pure RO when biofuel blends EPRO5 and PRO2.5 are used. The biggest brake thermal efficiency at maximum torque (0.40-0.41) and rated power (0.42-0.43) relative to that of RO (0.39) suggest blends PRO2.5 and EPRO5-7.5, respectively

First-principles calculation on dilute magnetic alloys in zinc blend crystal structure

International Nuclear Information System (INIS)

Ullah, Hamid; Inayat, Kalsoom; Khan, S.A; Mohammad, S.; Ali, A.; Alahmed, Z.A.; Reshak, A.H.

2015-01-01

Ab-initio calculations are performed to investigate the structural, electronic and magnetic properties of spin-polarized diluted magnetic alloys in zinc blende structure. The first-principles study is carried out on Mn doped III–V semiconductors. The calculated band structures, electronic properties and magnetic properties of Ga 1−x Mn x X (X=P, As) compounds reveal that Ga 0.75 Mn 0.25 P is half metallic turned to be metallic with increasing x to 0.5 and 0.75, whereas substitute P by As cause to maintain the half-metallicity nature in both of Ga 0.75 Mn 0.25 As and Ga 0.5 Mn 0.5 As and tune Ga 0.25 Mn 0.75 As to be metallic. Calculated total magnetic moments and the robustness of half-metallicity of Ga 0.75 Mn 0.25 P, Ga 0.75 Mn 0.25 As and Ga 0.5 Mn 0.5 As with respect to the variation in lattice parameters are also discussed. The predicted theoretical evidence shows that some Mn-doped III–V semiconductors can be effectively used in spintronic devices

Rheological Characterization of Isabgol Husk, Gum Katira Hydrocolloids, and Their Blends

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Vipin Kumar Sharma

2014-01-01

Full Text Available The rheological parameters of Isabgol husk, gum katira, and their blends were determined in different media such as distilled water, 0.1 N HCl, and phosphate buffer (pH 7.4. The blend properties of Isabgol husk and gum katira were measured for four different percentage compositions in order to understand their compatibility in dispersion form such as 00 : 100, 25 : 50, 50 : 50, 75 : 25, and 100 : 00 in the gel strength of 1 mass%. The miscibility of blends was determined by calculating Isabgol husk-gum katira interaction parameters by Krigbaum and Wall equation. Other rheological properties were analyzed by Bingham, Power, Casson, Casson chocolate, and IPC paste analysis. The study revealed that the power flow index “p” was less than “1” in all concentrations of Isabgol husk, gum katira, and their blends dispersions indicating the shear-thinning (pseudoplastic behavior. All blends followed pseudoplastic behavior at thermal conditions as 298.15, 313.15, and 333.15°K and in dispersion media such as distilled water, 0.1 N HCl, and phosphate buffer (pH 7.4. Moreover, the study indicated the applicability of these blends in the development of drug delivery systems and in industries, for example, ice-cream, paste, nutraceutical, and so forth.

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.

First-principles calculation on dilute magnetic alloys in zinc blend crystal structure

Energy Technology Data Exchange (ETDEWEB)

Ullah, Hamid, E-mail: hamidullah@yahoo.com [Department of Physics, Government Post Graduate Jahanzeb College, Saidu Sharif Swat (Pakistan); Inayat, Kalsoom [Department of Physics, Government Post Graduate Jahanzeb College, Saidu Sharif Swat (Pakistan); Khan, S.A; Mohammad, S. [Department of Physics, Materials Modeling Laboratory, Hazara University, Mansehra 21300 (Pakistan); Ali, A. [Department of Advanced Materials Science & Engineering, Hanseo University, Seosan-si, Chungnam-do 356-706 (Korea, Republic of); Alahmed, Z.A. [Department of Physics and Astronomy, King Saud University, Riyadh 11451 (Saudi Arabia); Reshak, A.H. [New Technologies-Research Center, University of West Bohemia, Univerzitni 8, 306 14 Pilsen (Czech Republic); Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia)

2015-07-01

Ab-initio calculations are performed to investigate the structural, electronic and magnetic properties of spin-polarized diluted magnetic alloys in zinc blende structure. The first-principles study is carried out on Mn doped III–V semiconductors. The calculated band structures, electronic properties and magnetic properties of Ga{sub 1−x}Mn{sub x}X (X=P, As) compounds reveal that Ga{sub 0.75}Mn{sub 0.25}P is half metallic turned to be metallic with increasing x to 0.5 and 0.75, whereas substitute P by As cause to maintain the half-metallicity nature in both of Ga{sub 0.75}Mn{sub 0.25}As and Ga{sub 0.5}Mn{sub 0.5}As and tune Ga{sub 0.25}Mn{sub 0.75}As to be metallic. Calculated total magnetic moments and the robustness of half-metallicity of Ga{sub 0.75}Mn{sub 0.25}P, Ga{sub 0.75}Mn{sub 0.25}As and Ga{sub 0.5}Mn{sub 0.5}As with respect to the variation in lattice parameters are also discussed. The predicted theoretical evidence shows that some Mn-doped III–V semiconductors can be effectively used in spintronic devices.

Properties of chicken manure pyrolysis bio-oil blended with diesel and its combustion characteristics in RCEM, Rapid Compression and Expansion Machine

Directory of Open Access Journals (Sweden)

Sunbong Lee

2014-06-01

Full Text Available Bio-oil (bio-oil was produced from chicken manure in a pilot-scale pyrolysis facility. The raw bio-oil had a very high viscosity and sediments which made direct application to diesel engines difficult. The bio-oil was blended with diesel fuel with 25% and 75% volumetric ratio at the normal temperature, named as blend 25. A rapid compression and expansion machine was used for a combustion test under the experimental condition corresponding to the medium operation point of a light duty diesel engine using diesel fuel, and blend 25 for comparison. The injection related pressure signal and cylinder pressure signal were instantaneously picked up to analyze the combustion characteristics in addition to the measurement of NOx and smoke emissions. Blend 25 resulted in reduction of the smoke emission by 80% and improvements of the apparent combustion efficiency while the NOx emission increased by 40%. A discussion was done based on the analysis results of combustion.

Characteristic of Irradiation Result Film of Poly-Propylene-Co-Ethylene/Poly-ε-Caprolactone and Poly-Propylene Grafted Maleic Anhydrate Blend

International Nuclear Information System (INIS)

Nikham

2004-01-01

The effect of gamma rays irradiation to film of melt-blending polypropylene-co-ethylene (CPP) and poly-ε-caprolactone (PCL) with polypropylene grafted maleic anhydride (PP-g-MAH) blend as compatibilizer has been studied. The objective of the research is to prepare the biodegradable polyblend. The composition blend of CPP/PCL with 0, 10, 15, 20 wt % PP-g-MAH i.e. 100/0, 75/25, 50/50, 25/75 and 0/100 were irradiated by using gamma rays 60 Co with activity 420 kCi at doses; 0, 50, 100, 150, 200 kGy, at dose rate 8.2 kGy/hrs and temperature 90 o C. The elongation at break, tensile strength, gel fraction, enzymatic degradation and heat resistance were evaluated. The results showed that the compatibility of PP-g-MAH to reach good enough polyblend is 20 % weight. Elongation at break film of CPP/PCL 50/50 blend which irradiated at dose 200 kGy decreased, whereas the tensile strength increased. Gel fraction and heat resistance of the film irradiated increased. Enzyme of lipase AK can degraded either without irradiated or irradiated film. Thus quality of the polyblend can be called as biodegradable plastic material. (author)

Forage Yield and Quality Performance of Rabi Cereals Sown Alone and In Blended Population of Variable Seed Ratios

International Nuclear Information System (INIS)

Tahir, M.; Zafar, N.

2016-01-01

Fodder crops are the main source of animal feed in Pakistan. However, the yield per acre is still far below than optimum production level of the livestock. From this perspective, a field trial was conducted using seeds of three cereal crops wheat, oat and barley sown alone and blended together at different seed proportions (100 percent: 0 percent, 75 percent + 25 percent, 50 percent + 50 percent and 25 percent + 75 percent) at the Agronomic Research Area, Department of Agronomy, University of Agriculture, Faisalabad, during 2013-14. The results showed that the crop mixtures and their variable seed ratios showed significant effects on fodder yield and quality traits. The maximum number of tillers, number of leaves plant/sup -1/, leaf area, crop growth rate, fresh weight plant/sup -1/, dry weight plant/sup -1/, green forage yield and dry matter yield were obtained in plots where barley was sown alone at 100 percent seed ratio. The highest crude fiber and total ash percentage was observed in plots where oat was sown alone at 100 percent seed ratio and crude protein percentage was highest when oat was blended together with barley at 75 percent + 25 percent seed ratios. (author)

Mechanical properties of polyamide 6,6/low density polyethylene blend by ionizing radiation

International Nuclear Information System (INIS)

Pino, Eddy S.; Feitosa, Marcos A.F.

2007-01-01

Polymer blending is a growing scientific and commercial development activity. In most of the cases, polymeric blends are formed by thermodynamically immiscible components. Such blends require the use of compatibilizers that, often, are copolymers, graft copolymers or any mean that improves the dispersion and adhesion of the blend phases. Compatibility of a polymer blend plays an important role in determining the blend properties for its end use. In this work, the improvement of mechanical properties of PA 6,6/LDPE 75/25% wt/wt composition blend, using electron radiation, was studied. Samples for mechanical test were melt-mixed in an extruder and then injection-molded. These samples were electron irradiated to overall doses of 50, 100, 150, 200 and 250 kGy. Tensile measurements have shown that the strength at break increases with an increase of radiation dose. Hardness Shore D measurements show that this property also increases as a function of radiation dose. On the other hand, Impact Izod tests show that the resistance to impact decreases with the increase of radiation dose. The behavior of these bulk and surface properties implies that ionizing radiation produces changes in the mechanical performance of the irradiated blend due to a combined radiation inducing effects, cross-linking and the compatibility of blend components. (author)

Ethanol content in different gasohol blend spills influences the decision-making on remediation technologies.

Science.gov (United States)

Vilela Steiner, Leonardo; Toledo Ramos, Débora; Rubini Liedke, Ana Maria; Serbent, Maria Pilar; Corseuil, Henry Xavier

2018-04-15

Gasohol blend spills with variable ethanol content exert different electron acceptor demands in groundwater and the distinct dynamics undergone by these blends underscores the need for field-based information to aid decision-making on suitable remediation technologies for each gasohol blend spill. In this study, a comparison of two gasohol releases (E10 (10:90 ethanol and gasoline, v/v) and E25 (25:75 ethanol and gasoline, v/v) under monitored natural attenuation (MNA) and nitrate biostimulation, respectively) was conducted to assess the most effective remediation strategy for each gasohol release. Microbial communities were assessed to support geochemical data as well as to enable the characterization of important population shifts that evolve during biodegradation processes in E25 and E10 field experiments. Results revealed that natural attenuation processes sufficiently supported ethanol and BTEX compounds biodegradation in E10 release, due to the lower biochemical oxygen demand they exert relative to E25 blend. In E25 release, nitrate reduction was largely responsible for BTEX and ethanol biodegradation, as intended. First-order decay constants demonstrated that ethanol degradation rates were similar (p remediation technologies (2.05 ± 0.15 and 2.22 ± 0.23, for E25 and E10, respectively) whilst BTEX compounds exhibited different degradation rates (p > 0.05) that were higher for the experiment under MNA (0.33 ± 0.06 and 0.43 ± 0.03, for E25 and E10, respectively). Therefore, ethanol content in different gasohol blends can influence the decision-making on the most suitable remediation technology, as MNA processes can be applied for the remediation of gasohol blends with lower ethanol content (i.e., 10% v/v), once the aquifer geochemical conditions provide a sufficient electron acceptor pool. To the best of our knowledge, this is the first field study to monitor two long-term gasohol releases over various time scales in order to assess

Effect of blending ratio to the liquid product on co-pyrolysis of low rank coal and oil palm empty fruit bunch

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Zullaikah Siti

2018-01-01

Full Text Available The utilization of Indonesia low rank coal should be maximized, since the source of Indonesia law rank coals were abundant. Pyrolysis of this coal can produce liquid product which can be utilized as fuel and chemical feedstocks. The yield of liquid product is still low due to lower of comparison H/C. Since coal is non-renewable source, an effort of coal saving and to mitigate the production of greenhouse gases, biomass such as oil palm empty fruit bunch (EFB would added as co-feeding. EFB could act as hydrogen donor in co-pyrolysis to increase liquid product. Co-pyrolysis of Indonesia low rank coal and EFB were studied in a drop tube reactor under the certain temperature (t= 500 °C and time (t= 1 h used N2 as purge gas. The effect of blending ratios of coal/EFB (100/0, 75/25, 50/50, 25/75 and 0/100%, w/w % on the yield and composition of liquid product were studied systematically. The results showed that the higher blending ratio, the yield of liquid product and gas obtained increased, while the char decreased. The highest yield of liquid product (28,62 % was obtained used blending ratio of coal/EFB = 25/75, w/w%. Tar composition obtained in this ratio is phenol, polycyclic aromatic hydrocarbons, alkanes, acids, esters.

Fabrication and Characterization of Electrospun Polycaprolactone Blended with Chitosan-Gelatin Complex Nanofibrous Mats

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Yongfang Qian

2014-01-01

Full Text Available Design and fabrication of nanofibrous scaffolds should mimic the native extracellular matrix. This study is aimed at investigating electrospinning of polycaprolactone (PCL blended with chitosan-gelatin complex. The morphologies were observed from scanning electron microscope. As-spun blended mats had thinner fibers than pure PCL. X-ray diffraction was used to analyze the degree of crystallinity. The intensity at two peaks at 2θ of 21° and 23.5° gradually decreased with the percentage of chitosan-gelatin complex increasing. Moreover, incorporation of the complex could obviously improve the hydrophilicity of as-spun blended mats. Mechanical properties of as-spun nanofibrous mats were also tested. The elongation at break of fibrous mats increased with the PCL content increasing and the ultimate tensile strength varied with different weight ratios. The as-spun mats had higher tensile strength when the weight ratio of PCL to CS-Gel was 75/25 compared to pure PCL. Both as-spun PCL scaffolds and PCL/CS-Gel scaffolds supported the proliferation of porcine iliac endothelial cells, and PCL/CS-Gel had better cell viability than pure PCL. Therefore, electrospun PCL/Chitosan-gelatin nanofibrous mats with weight ratio of 75/25 have better hydrophilicity mechanical properties, and cell proliferation and thus would be a promising candidate for tissue engineering scaffolds.

Formation and early hydration characteristics of C2.75B1.25A3$ in binary system of C2.75B1.25A3$-C2S

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Wang, Shoude

2016-09-01

Full Text Available C2.75B1.25A3$ (2.75CaO•1.25BaO• 3Al2O3• SO3 is one of the important minerals and it govern-directly the early-strength of belite-barium calcium sulphoaluminate cement. In this paper a binary system C2.75B1.25A3$-C2S is selected to investigate the formation of C2.75B1.25A3$. In the range of 1100 °C–1200 °C, the earlier formed C2S hinders the formation of C2.75B1.25A3$. On the contrary, when the temperature is in the range of 1200 °C–1350 °C, the initially formed C2S could provide a surface for the nucleation of C2.75B1.25A3$ and cut down the potential barrier (?Gk* for the heterogeneous nucleation of C2.75B1.25A3$, which contributes to its formation. Moreover, at 1350 °C, the large amount of previously formed C2S benefits the extent of formation of C2.75B1.25A3$. The possible reason was that it could prevent sulfur evaporation. In early hydration age, AFm and AFt originating from C2.75B1.25A3$ hydration are found within 2 h and 12 h under 95% RH at 1 °C, respectively, whereas C2S is unhydrated at this moment.En el cemento de sulfoaluminato de calcio y bario, el C2.75B1.25A3$ (2.75CaO•1.25BaO• 3Al2 O3• SO3 es una de las principales fases, y regula directamente la resistencia inicial del cemento. En este trabajo, se ha seleccionado el sistema binario C2.75B1.25A3$-C2S para investigar la formación de C2.75B1.25A3$. En el rango de 1100 °C-1200 °C, el C2S formado anteriormente impide la formación de C2.75B1.25A3$, mientras que cuando la temperatura está entre 1200 °C-1350 °C, el C2S proporcionaría una superficie de nucleación de C2.75B1.25A3$ reduciendo la barrera de potencial (?Gk* para la nucleación heterogénea de C2.75B1.25A3$, lo que contribuye a su formación. Además, a 1350 °C, la gran cantidad de C2S formado beneficia la formación de C2.75B1.25A3$, ya que podía prevenir la evaporación del azufre. En las primeras etapas de la hidratación (entre 2 y 12h y 95% HR a 1 ºC se pueden encontrar AFM y AFt

The influence of electron beam irradiation on the mechanical and thermal properties of Poly (ether-block-amide) blends

International Nuclear Information System (INIS)

Murray, Kieran A.; Kennedy, James E.; McEvoy, Brian; Vrain, Olivier; Ryan, Damien; Cowman, Richard; Higginbotham, Clement L.

2014-01-01

High energy electron beam irradiation of Poly (ether-block-amide) (Pebax) can induce modifications and/or degradation to transpire in the material subsequent to treatment. To minimise this, Pebax was blended with three stabilisers where each formulation was subjected to electron beam radiation at doses of 25, 50 and 75 kGy. Mechanical testing revealed that the virgin Pebax and the Pebax blended with Irganox B215 provided the best radiation resistance in terms of the tensile strength, elongation at break and Young's modulus. Upon increase in radiation dose from 25 to 75 kGy, a gradual diminution was observed for the melt flow index (MFI) of the virgin Pebax, whereas Pebax blended with Irganox B215 had a minute effect on the properties post irradiation. This study provides evidence that the stabilisers used can either promote undesirable effects or enhance the radiation resistance of Pebax material following radiation exposure. Highlights: • Mechanical properties of Pebax and Irganox 565 can be controlled by radiation dose • Virgin Pebax and Pebax blended with Irgnaox B215 provides good radiation resistance • MFI decreases gradually for the Virgin Pebax with an increase in radiation dose • Molecular weight of Pebax and Irganox B215 is less effected by radiation dose • Simultaneous chain scission and crosslinking/branching occurs during irradiation

Biodegradable blends of urea plasticized thermoplastic starch (UTPS) and poly(ε-caprolactone) (PCL): Morphological, rheological, thermal and mechanical properties.

Science.gov (United States)

Correa, Ana Carolina; Carmona, Vitor Brait; Simão, José Alexandre; Capparelli Mattoso, Luiz Henrique; Marconcini, José Manoel

2017-07-01

Biodegradable blends of urea plasticized thermoplastic starch (UTPS) and poly(ε-caprolactone) (PCL) were prepared in a co-rotating twin screw extruder. The UTPS and PCL content varied in a range of 25wt%. The materials were characterized by capillary rheometry, scanning electron microscopy (SEM), termogravimetry (TGA), differential scanning calorimetry (DSC) and tensile tests. Capillary rheometry showed better interaction between UTPS and PCL at 110°C than at 130°C. SEM showed immiscibility of all blends and good dispersion of UTPS in PCL matrix up to 50wt%. However, a co-continuous morphology was found for UTPS/PCL 75/25. Thermal analysis showed that introducing PCL in UTPS, increased T onset due to higher thermal stability of PCL, and blends presented an intermediate behavior of neat polymers. The presence of PCL in blends improved significantly the mechanical properties of neat UTPS. Because they are totally biodegradable, these blends can be vehicles for controlled or slow release of nutrients to the soil while degraded. Copyright © 2017 Elsevier Ltd. All rights reserved.

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)

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...

Characterization of proton conducting blend polymer electrolyte using PVA-PAN doped with NH{sub 4}SCN

Energy Technology Data Exchange (ETDEWEB)

Premalatha, M. [PG & Research Department of Physics, N.M.S.S.Vellaichamy Nadar College, Madurai-625 019 (India); Materials Research Center, Coimbatore-641 045 (India); Mathavan, T., E-mail: tjmathavan@gmail.com, E-mail: kingslin.genova20@gmail.com [PG & Research Department of Physics, N.M.S.S.Vellaichamy Nadar College, Madurai-625 019 (India); Selvasekarapandian, S. [Materials Research Center, Coimbatore-641 045 (India); Genova, F. Kingslin Mary, E-mail: tjmathavan@gmail.com, E-mail: kingslin.genova20@gmail.com; Umamaheswari, R. [Department of physics, S.F.R College for Women, Sivakasi-626 128 (India)

2016-05-23

Polymer electrolytes with proton conductivity based on blend polymer using polyvinyl alcohol (PVA) and poly acrylo nitrile (PAN) doped with ammonium thiocyanate have been prepared by solution casting method using DMF as solvent. The complex formation between the blend polymer and the salt has been confirmed by FTIR Spectroscopy. The amorphous nature of the blend polymer electrolytes have been confirmed by XRD analysis. The highest conductivity at 303 K has been found to be 3.25 × 10{sup −3} S cm{sup −1} for 20 mol % NH{sub 4}SCN doped 92.5PVA:7.5PAN system. The increase in conductivity of the doped blend polymer electrolytes with increasing temperature suggests the Arrhenius type thermally activated process. The activation energy is found to be low (0.066 eV) for the highest conductivity sample.

Influence of enzymatic and chemical interesterification on crystallisation properties of refined, bleached and deodourised (RBD) palm oil and RBD palm kernel oil blends.

Science.gov (United States)

Norizzah, Abd Rashid; Nur Azimah, Kamarulzaman; Zaliha, Omar

2018-04-01

Interesterification reaction involves rearrangement of the fatty acid radicals on the glycerol backbone, either randomly (chemical interesterification) or regioselectivity (enzymatic interesterification). Refined, bleached and deodourised palm oil (RBDPO) and palm kernel oil (RBDPKO) were blended in ratios from 25:75 to 75:25 (wt/wt). All blends were subjected to enzymatic (EI) and chemical interesterification (CI) using Lipozyme TL IM (4% w/w) and sodium methoxide (0.2% m/m) as the catalysts, respectively. The effect of EI and CI on the triacylglycerol (TAG) composition, thermal behaviour, polymorphism, crystal morphology and crystallisation kinetics were studied. The aim of this research is to characterise the nature of crystals in food product for certain desired structure. The crystallisation behaviour discussed in this study involves microstructure (PLM), polymorphism (XRD), thermal properties and crystallisation kinetics by DSC. The alteration in TAG composition was greater after CI as compared to EI with the reduction of LaLaLa (from 11.00% to 5.15%) and POO (from 14.28% to 4.87%). The DSC complete melting and crystallisation temperature of blend with 75% PO increased after CI, from 39.58 °C to 41.67 °C and from -30.84 °C to -28.33 °C, respectively. EI contributed to finer crystals than CI. However, the β' and β polymorph mixture and crystallisation kinetics (n = 2) of PO-PKO blends did not change after CI and EI. The knowledge on controlling crystallisation of RBDPO and RBDPKO blends is vital for proper processing condition like margarine production. Copyright © 2018 Elsevier Ltd. All rights reserved.

Development of occlusal traits and dental arch space from adolescence to adulthood: a 25-year follow-up study of 245 untreated subjects.

Science.gov (United States)

Jonsson, Teitur; Arnlaugsson, Sigurjon; Saemundsson, Sigurdur Runar; Magnusson, Thordur Eydal

2009-04-01

The purpose of this study was to examine longitudinally the development of specific occlusal traits and space conditions in an Icelandic sample. The sample comprised 245 adolescents examined clinically in the late mixed or permanent dentition and again 25 years later. All subjects were orthodontically untreated, and all had the full complement of teeth at both examinations. A significant increase in the prevalence of mandibular anterior crowding and mesial molar relationships and a decrease in the prevalence of excessive overjet and maxillary anterior spacing were seen. The persistence of malocclusion traits ranged from 17.9% to 53.4% for maxillary anterior spacing and crowding, mandibular spacing, overjet, overbite, and distal molar occlusion, whereas anterior mandibular crowding and molar crossbite were still found in 72.7% and 75.0%, respectively, at the second examination. Normal occlusal traits and space conditions at adolescence stayed mostly unchanged, with the exception of 11.2% of the subjects, who developed mandibular anterior crowding between the first and second examinations. Deterioration of normal occlusal traits and space relationships was uncommon in this study, whereas self-correction of malocclusion traits and space anomalies was relatively frequent.

Study of electron beam irradiation effects on morphologic properties of the PET/PP/PE/EVA polymeric blend

International Nuclear Information System (INIS)

Rossini, Edvaldo L.; Silva, Leonardo G. Andrade e; Wiebeck, Helio

2009-01-01

Amidst the pollutants, plastics and especially the 'PET bottles' packaging type, which comprise of poly(ethylene terephthalate) (PET), polypropylene (PP), polyethylene (PE) and poly[ethylene-co-(vinyl acetate)] (EVA) have been causing big damage to the environment. In this work, the polymeric blend PET/PP/PE/EVA was obtained by mechanical recycling 'PET bottles' after consumption, with the objective of finding a solution for this environmental problem. It was also studied the different ionizing radiation dose effects (25, 50, 75, 100, 150, 200, 300, 400 and 500 kGy) on the blend properties using an electron beam accelerator. The morphologic properties of the non-irradiated and irradiated polymeric blend were evaluated by the Light Microscopy (LM) and Scanning Electron Microscopy (SEM). The analysis of the results appeared to be a not mixing and compatible blend. The use of the ionizing radiation improved the homogeneity of the blend. These modifications have been randomized and irregular, depending directly on the dose of applied radiation. (author)

Study of electron beam irradiation effects on morphologic properties of the PET/PP/PE/EVA polymeric blend

Energy Technology Data Exchange (ETDEWEB)

Rossini, Edvaldo L.; Silva, Leonardo G. Andrade e, E-mail: lgasilva@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Wiebeck, Helio, E-mail: hwiebeck@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Escola Politecnica

2009-07-01

Amidst the pollutants, plastics and especially the 'PET bottles' packaging type, which comprise of poly(ethylene terephthalate) (PET), polypropylene (PP), polyethylene (PE) and poly[ethylene-co-(vinyl acetate)] (EVA) have been causing big damage to the environment. In this work, the polymeric blend PET/PP/PE/EVA was obtained by mechanical recycling 'PET bottles' after consumption, with the objective of finding a solution for this environmental problem. It was also studied the different ionizing radiation dose effects (25, 50, 75, 100, 150, 200, 300, 400 and 500 kGy) on the blend properties using an electron beam accelerator. The morphologic properties of the non-irradiated and irradiated polymeric blend were evaluated by the Light Microscopy (LM) and Scanning Electron Microscopy (SEM). The analysis of the results appeared to be a not mixing and compatible blend. The use of the ionizing radiation improved the homogeneity of the blend. These modifications have been randomized and irregular, depending directly on the dose of applied radiation. (author)

Comparison of gaseous exhaust indices of the F109 turbofan using three different blends of petroleum-based Jet-A and camelina-based Jet-A

Science.gov (United States)

Kozak, Brian John

This research project focused on the collection and comparison of gaseous exhaust emissions of the F109 turbofan engine using petroleum-based Jet-A and two different blends of camelina-based Jet-A. Simulated landing and takeoff cycles were used to collect gaseous exhaust emissions. Unburned hydrocarbon (HC), nitrogen oxide (NOx), and carbon moNOxide (CO) exhaust indices (EIm) were calculated using ICAO Annex 16 Volume II formulae. Statistical analyses were performed on the Elm data. There was no significant difference in HC EIm and CO EI m among the three fuels at takeoff thrust. There were significant differences among the fuels for NOx EIm. 50% Jet-A 50% camelina produced the highest NOx EIm, then 75% Jet-A 25% camelina and finally Jet-A. At climb thrust, both blends of camelina fuel produced higher NOx EIm but no difference in CO EIm and HC EIm as Jet-A. At approach thrust, both blends of camelina fuel produced higher NOx EIm, lower CO EIm, and no difference in HC EIm as Jet-A. At idle thrust, there was no significant difference among the fuels for NOx EIm. There were significant differences among the fuels for HC EIm. Jet-A and 50% Jet-A 50% both produced higher HC EIm as 75% Jet-A 25% camelina. There were significant differences among the fuels for CO EI m. Jet-A produced the highest CO EIm, then 75% Jet-A 25% camelina and finally 50% Jet-A 50% camelina.

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...

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.

Biscuit-making potential of millet/pigeon pea flour blends.

Science.gov (United States)

Eneche, E H

1999-01-01

Biscuits were produced from millet flour (MF) and pigeon pea flour (PPF) blends. The various ratios of MF to PPF used were 100:0, 75:25, 65:35, and 50:50. The biscuits were analyzed for their nutritional composition. They all contained high proportions of protein (7.5-15.2%), fat (17.1-18.1%) and digestible carbohydrate (60.2-66.5%). The moisture content was in the range 5.0 to 6.6%, ash 1.5-2.3% and crude fiber 0-0.1%. Sensory evaluation results indicated that all the biscuits had high sensory ratings for all the selected attributes evaluated. The recipe with the 65% MF/35% PPF blend resulted in the highest scores for flavor, texture and general acceptability. There was no significant difference (p > 0.05) between all the biscuits and the familiar Nasco short cake biscuit (reference) in flavor, color, texture and general acceptability.

Combustion and Emission Characteristics of Variable Compression Ignition Engine Fueled with Jatropha curcas Ethyl Ester Blends at Different Compression Ratio

Directory of Open Access Journals (Sweden)

Rajneesh Kumar

2014-01-01

Full Text Available Engine performance and emission characteristics of unmodified biodiesel fueled diesel engines are highly influenced by their ignition and combustion behavior. In this study, emission and combustion characteristics were studied when the engine operated using the different blends (B10, B20, B30, and B40 and normal diesel fuel (B0 as well as when varying the compression ratio from 16.5 : 1 to 17.5 : 1 to 18.5 : 1. The change of compression ratio from 16.5 : 1 to 18.5 : 1 resulted in 27.1%, 27.29%, 26.38%, 28.48%, and 34.68% increase in cylinder pressure for the blends B0, B10, B20, B30, and B40, respectively, at 75% of rated load conditions. Higher peak heat release rate increased by 23.19%, 14.03%, 26.32%, 21.87%, and 25.53% for the blends B0, B10, B20, B30, and B40, respectively, at 75% of rated load conditions, when compression ratio was increased from16.5 : 1 to 18.5 : 1. The delay period decreased by 21.26%, CO emission reduced by 14.28%, and NOx emission increased by 22.84% for B40 blends at 75% of rated load conditions, when compression ratio was increased from 16.5 : 1 to 18.5 : 1. It is concluded that Jatropha oil ester can be used as fuel in diesel engine by blending it with diesel fuel.

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

KARAKTERISTIK MINYAK CAMPURAN RED PALM OIL DENGAN PALM KERNEL OLEIN (Characteristics of Oil Blends from Red Palm Oil and Palm Kernel Olein

Directory of Open Access Journals (Sweden)

Maria Ulfah

2016-10-01

Full Text Available Characteristics of oil blends has been produced from red palm oil (RPO and palm kernel olein (PKOo with seven ratios with a total of 100, namely A (0:100, B (25:75, C (40:60, D (50:50, E (60:40, F (75:25 and G (100:0 v/v investigated with randomized complete block design. The result showed that different of ratio levels RPO and PKOo have some effects on peroxide value, saponification value, melting point, cloud point and β-carotene content from RPO-PKOo oil blends, but has not effect on free fatty acid content. Higher level of PKOo content on formulas oil blends were decreased of saponification value and melting point, but was increased of cloud point. The best of RPOPKOo oil blends has been obtained at ratio 50:50 (v/v, with 459.52 ppm β-carotene, 1.35 meq/kg peroxide value, 0.09 % free fatty acid, 202.60 saponification value, 24.15 oC melting point and 7.15 oC cloud point. Fatty acids composition were 1.24 % capric acid, 29.00 % lauric acid, 10.09 % miristic acid, 23.10 % palmitic acid, 5.84 linoleic acid, 27.30 % oleic acid and 3.43 % stearic acid. Keywords: Red palm oil, palm kernel olein, oil blends, chemical and physical properties ABSTRAK Sifat-sifat minyak campuran yang dihasilkan dari red palm oil (RPO dan palm kernel olein (PKOo dengan tujuh tingkat rasio yang totalnya 100, yaitu A (0:100, B (25:75, C (40:60, D (50:50, E (60:40, F (75:25 dan G (100:0 (v/v dikaji menggunakan rancangan acak lengkap kelompok. Hasil penelitian menunjukkan bahwa rasio RPO:PKOo mempengaruhi angka peroksida, angka penyabunan, melting point, cloud point dan kadar β-karoten dari minyak campuran RPO-PKOo yang dihasilkan, namun tidak mempengaruhi kadar asam lemak bebas. Peningkatan jumlah PKOo yang ditambahkan dalam minyak campuran RPO-PKOo, akan menurunkan angka penyabunan dan melting point, namun akan menaikkan cloud point. Produk minyak campuran RPO-PKOo terbaik diperoleh pada rasio 50:50 (v/v, dengan kadar β-karoten 459,52 ppm, angka peroksida 1,35 meq

Blendas PHB/copoliésteres biodegradáveis : biodegradação em solo Biodegradable PHB/copolyester blends : biodegradation in soil

Directory of Open Access Journals (Sweden)

Suzan A. Casarin

2013-01-01

Full Text Available Este trabalho apresenta os resultados do comportamento de blendas do polímero biodegradável PHB poli(hidroxibutirato com os copoliésteres também biodegradáveis EastarBio® e Ecoflex®, na composição de 75% de PHB e 25% dos copoliésteres, em contato com solo composto simulado. Foi também avaliada a influência da adição de pó de serra ou farinha de madeira, na proporção de 70% da blenda e 30% de pó de serra (p.d.s.. A biodegradação foi avaliada para amostras após 30, 60 e 90 dias em contato com solo, através de análises gravimétricas, morfológicas e mecânicas. A preparação inicial dos grânulos dos compostos poliméricos foi feita por extrusão, utilizando uma extrusora dupla-rosca e a moldagem dos corpos de prova foi realizada através da moldagem por injeção. Os materiais estudados biodegradam nas condições testadas. A blenda PHB/EastarBio® (75/25 + 30% p.d.s. apresentou maior redução de massa, 29% após 90 dias. Notou-se que a biodegradação se inicia pela superfície do material e que 90 dias são insuficientes para observar alterações internas.This paper reports on blends made with the biodegradable polymers poly(hydroxybutyrate (PHB and Eastar Bio® or Ecoflex® copolyesters, in contact with simulated compound soil. The blends had 75% of PHB and 25% of copolyesters. We also analyzed the influence from adding 30% of powder-wood or wood flour (WPC to 70% of the blend. Biodegradation was analyzed for samples after 30, 60 and 90 days in contact with soil, through thermogravimetric, morphological and mechanical analyses. The initial preparation of the granules of polymeric compounds was made by extrusion, using a twin-screw extruder and the molding of the specimens was performed by injection molding. The analysis indicated material biodegradation under the conditions tested. The PHB/Eastar Bio® blend (75/25 + 30% WPC exhibited the highest degradation with 29% of mass loss at the end of 90 days. Biodegradation

Microstructure and strengthening mechanisms in an FCC structured single-phase nanocrystalline Co25Ni25Fe25Al7.5Cu17.5 high-entropy alloy

International Nuclear Information System (INIS)

Fu, Zhiqiang; Chen, Weiping; Wen, Haiming; Zhang, Dalong; Chen, Zhen; Zheng, Baolong; Zhou, Yizhang; Lavernia, Enrique J.

2016-01-01

We report on a study of the design, phase formation, microstructure, mechanical behavior and strengthening mechanisms of a novel single-phase Co 25 Ni 25 Fe 25 Al 7.5 Cu 17.5 (at.%) high-entropy alloy (HEA). In this investigation, a bulk nanocrystalline (nc) Co 25 Ni 25 Fe 25 Al 7.5 Cu 17.5 HEA with the face-centered cubic (FCC) crystal structure was fabricated by mechanical alloying (MA) followed by consolidation via spark plasma sintering (SPS). The X-ray diffraction (XRD) and transmission electron microscopy (TEM) results revealed that a single FCC solid-solution phase with an average grain diameter of 24 nm was produced following MA. Following SPS, bulk samples exhibiting a bimodal microstructure with both nanoscale grains and ultra-fine grains (UFGs) and with an average grain diameter of 95 nm were obtained, possessing a single FCC solid-solution phase identical to that in the milled powders. The single-phase feature of the Co 25 Ni 25 Fe 25 Al 7.5 Cu 17.5 HEA principally resulted from remarkably high mutual solubility in most binary atom-pairs of the constituent elements, which appears to correspond to a high entropy of mixing. Approximately 5 vol.% of nanoscale twins were observed in the bulk nc samples. The bulk nc Co 25 Ni 25 Fe 25 Al 7.5 Cu 17.5 HEA exhibits a compressive yield strength of 1795 MPa with a hardness of 454 Hv, which is dramatically higher than the yield strength of most previously reported FCC structured HEAs (∼130–700 MPa). Compared to those of the bulk coarse-grained (CG) Co 25 Ni 25 Fe 25 Al 7.5 Cu 17.5 HEA fabricated by arc-melting, the yield strength and Vickers hardness values of the bulk nc samples increased by 834.9% and 251.9%, respectively. Quantitative calculations of the respective contributions from each strengthening mechanism demonstrate that grain boundary strengthening and dislocation strengthening are principally responsible for the measured ultra-high strength of the bulk nc Co 25 Ni 25 Fe 25 Al 7.5 Cu 17.5 HEA.

Evaluation of the solubility of the HPMC: PVA blends in biological fluids in vitro

Directory of Open Access Journals (Sweden)

Sara Elis Bianchi

2011-01-01

Full Text Available Polymers are often used to coat tablets for controlled drug release. The purpose of this study is to evaluate the solubility of the HPMC and PVA blend compared to isolated polymers in solutions with a pH of biological fluids (6 and 1.2 and the dissolution of capsules obtained using theophylline granules produced with the HPMC/PVA 25/75 blend as a matrix and as coating. HPMC is completely solubilized in the medium that simulates the pH of the stomach and intestine, and PVA is the polymer that allows controlling the solubility of the blend in the medium, with a differents pH. The dissolution time was monitored by UV absorbance with maximum theophylline at 269 nm. The theophylline was released immediately in the granules, and in the capsules 78.4% after 30 minutes and 97.4%, after 120 minutes. Thus, PVA can potentially control the drug solubilization, contributing to obtaining modified release systems.

Gelatinized and nongelatinized corn starch/ poly(epsilon-caprolactone blends: characterization by rheological, mechanical and morphological properties

Directory of Open Access Journals (Sweden)

Derval S. Rosa

2004-09-01

Full Text Available Poly(epsilon-caprolactone/corn starch blends containing 25, 50 and 75 wt.% starch were prepared by mechanical processing and characterized by the melt flow index (MFI, tensile test and scanning electron microscopy (SEM. For comparison, starch was used in gelatinized and nongelatinized forms and was also characterized by viscography. The addition of starch to poly(epsilon-caprolactone reduced the MFI values, the tensile strength and the elongation at break, whereas the modulus increased. The reductions in the MFI and tensile properties were most evident when gelatinized starch was used. Viscography and SEM showed that starch was well gelatinized by the gelatinization process. Blends containing nongelatinized starch showed a good dispersion of starch but poor interfacial interactions.

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.

Gelatinized and nongelatinized corn starch/ poly(epsilon-caprolactone) blends: characterization by rheological, mechanical and morphological properties

OpenAIRE

Rosa,Derval S.; Guedes,Cristina G. F.; Pedroso,Andréa G.

2004-01-01

Poly(epsilon-caprolactone)/corn starch blends containing 25, 50 and 75 wt.% starch were prepared by mechanical processing and characterized by the melt flow index (MFI), tensile test and scanning electron microscopy (SEM). For comparison, starch was used in gelatinized and nongelatinized forms and was also characterized by viscography. The addition of starch to poly(epsilon-caprolactone) reduced the MFI values, the tensile strength and the elongation at break, whereas the modulus increased. T...

ac impedance, DSC and FT-IR investigations on (x)PVAc-(1 - x)PVdF blends with LiClO4

International Nuclear Information System (INIS)

Baskaran, R.; Selvasekarapandian, S.; Kuwata, N.; Kawamura, J.; Hattori, T.

2006-01-01

The blended polymer electrolytes comprising poly(vinyl acetate) (PVAc)-poly(vinylidene fluoride) (PVdF) have been prepared for different blend composition with constant lithium perchlorate (LiClO 4 ) ratio by solution casting technique. The formation of the blend polymer electrolyte complex has been confirmed by FT-IR spectroscopy analysis. DSC analysis has been performed in order to observe the change in transition temperature that is caused by the blending of polymers and addition of LiClO 4 . The ac impedance and dielectric spectroscopy studies are carried out on the blended matrix to identify the optimized blend composition, which is having high ionic conductivity. The temperature dependence of conductivity of the polymer electrolytes is found to follow VTF type equation. The high ionic conductivity of 6.4 x 10 -4 S cm -1 at 343 K has been observed for blended polymer electrolyte having blend ratio 75:25 (PVAc:PVdF). The ionic transference number of mobile ions has been estimated by Wagner's polarization method and the value is reported to be t ion is 0.95-0.98 for all the blended samples. The modulus spectra reveal the non-Debye nature and distribution of relaxation times of the samples. The dielectric spectra show the low frequency dispersion, which implies the space charge effects arising from the electrodes

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....

Dielectric relaxation in glassy Se75In25− xPbx alloys

Indian Academy of Sciences (India)

In this paper we report the effect of Pb incorporation in the dielectric properties of a-Se75In25 glassy alloy. The temperature and frequency dependence of the dielectric constants and the dielectric losses in glassy Se75In25−Pb ( = 0, 5, 10 and 15) alloys in the frequency range (1 kHz–5 MHz) and temperature range ...

First principles study of structural, electronic, magnetic and elastic properties of Mg{sub 0.75}TM{sub 0.25}S (TM=Mn, Fe, Co, Ni)

Energy Technology Data Exchange (ETDEWEB)

Gous, M.H., E-mail: gousph@hotmail.fr; Meddour, A., E-mail: a_meddour@yahoo.fr; Bourouis, Ch., E-mail: bourouisse_ch@yahoo.fr

2017-01-15

The objective of this work is to predict the structural, electronic, magnetic and elastic properties of Mg{sub 1−x}TM{sub x}S (TM=Mn, Fe, Co and Ni) compound in the zinc blende Ferromagnetic phase using first principal approach. The structural and elastic properties are performed using the generalized gradient approximation proposed by Wu and Cohen(WC-GGA). However, the electronic and magnetic properties have been performed using modified Becke-Johnson potential combined with the LDA correlation (mBJLDA). The results show that all compounds Mg{sub 1−x}Mn{sub x}S, Mg{sub 1−x}Fe{sub x}S and Mg{sub 1−x}Ni{sub x}S exhibit a half-metallic ferromagnetic character with 100% spin-polarization at the Fermi level, except Mg{sub 1−x}Co{sub x}S is a metal. For each compounds study here, the total magnetic momentum is an integer equal to magnetic moments of TM atom in their free space charge value. Due to the p–d hybridization, there is a small local magnetic moment on the Mg and S sites; whereas, the local magnetic moments of TM atom reduce from their free space charge value. In addition, we investigate the mechanical behavior of MgS and Mg{sub 1−x}TM{sub x}S; all compounds studied here are mechanically stable and exhibit a strong anisotropic behavior. - Highlights: • Our results could be a prediction for coming works. • According to our results of electronic properties: Mg{sub 0.75}Co{sub 0.25}S is metal. Mg{sub 0.75}Mn{sub 0.25}S, Mg{sub 0.75}Fe{sub 0.25}S and Mg{sub 0.75}Ni{sub 0.25}S exhibit half-metallic ferromagnetic behavior with 100% spin polarization at Fermi level. • We found that MgS and Mg{sub 0.75}TM{sub 0.25}S (TM=Mn, Fe, Co and Ni) compounds are mechanically stable, ductile materials and have an anisotropic Young's Modulus. • It is likely that these materials have a high Curie temperature.

Triacylglycerol composition, physico-chemical characteristics and oxidative stability of interesterified canola oil and fully hydrogenated cottonseed oil blends.

Science.gov (United States)

Imran, Muhammad; Nadeem, Muhammad

2015-10-29

Partial hydrogenation process is used worldwide to produce shortening, baking, and pastry margarines for food applications. However, demand for such products is decreased during last decade due to their possible links to consumer health and disease. This has raised the need to replace hydrogenation with alternative acceptable interesterification process which has advantage in context of modifying the physico-chemical properties of edible fat-based products. Therefore, the main mandate of research was the development of functional fat through chemical interesterification of canola oil (CaO) and fully hydrogenated cottonseed oil (FHCSO) mixtures. Blends were prepared in the proportions of 75:25 (T1), 50:50 (T2) and 25:75 (T3) of CaO:FHCSO (w/w). Interesterification was performed using sodium methoxide (0.2 %) as catalyst at 120 °C, under reduced pressure and constant agitation for 60 minutes. The non-interesterified and interesterified CaO:FHCSO blends were evaluated for triacylglycerol (TAG) composition, physico-chemical characteristics, oxidative stability and consumer acceptability at 0, 30 and 60 days of storage interval. The oleic acid (58.3 ± 0.6 %) was predominantly present in CaO while the contents of stearic acid (72 ± 0.8 %) were significantly higher in FHCSO. Maximum trisaturated (S3) contents (63.9 ± 0.5 %) were found in T3 while monounsaturated (S2U), diunsaturated (U2S) and triunsaturated (U3) contents were quite low in T2 and T3 before interesterification. A marked reduction in S3 and U3 contents with concomitant increase in S2U and U2S contents was observed for all CaO:FHCSO blends on interesterification. During storage, the changes in S3, S2U and U2S contents were not found significant (p ≥ 0.05). However, maximum decrease 13 %, 7.5 and 5.6 % in U3 contents for T1, T2 and T3 was noted after 60-days of interesterification, respectively. The Lovibond color R, melting point, refractive index, specific gravity, peroxide and free

Compatibility of polyamide 6.6 and low density polyethylene polymeric blend using electron beam ionizing radiation

International Nuclear Information System (INIS)

Feitosa, Marcos Antonio Fernandes

2008-01-01

The plastic industry has recognized that mixture of polymers, called polymeric blends, yields new materials with improve properties and better features of those of the polymer blended. In most of the cases, blends are formed by immiscible components presenting separated phases, micro-structures or morphologies. One of the main factors for good mechanical performance is the interfacial adhesion of the blend components. The improvement of miscibility between the polymer components and the enhancement of blend performance is denominated of compatibility. This compatibility can be achieved by chemical methods or using ionizing radiation. The present work has as a main objective the study of the effect of the ionizing radiation from electron beam in the compatibility of the polyamide (PA) 6.6 and low density polyethylene (LDPE) 75%/25% wt blend, in the range of applied doses from 50 to 250 kGy. The compatibility effect was evaluated by mechanical test, which has shown improvement in the tensile strength and hardness properties and a reduction of the impact resistant. This mechanical behavior can be considered as a combination effect of the cross-linking, induced in the molecular structure on the polymers, and the increase of the miscibility of the blend components. The degree of compatibility was evaluated by the behavior of the glass transition temperatures (T g ) for the blend components obtained by dynamic mechanical analysis (DMA) measurements. The results have shown that the values of T g for PA 6.6 and LDPE get near by 8 deg C showing that the ionizing radiation have promoted a compatibility effect on the irradiated blend. (author)

Effect of antioxidant on the oxidation stability and combustion–performance–emission characteristics of a diesel engine fueled with diesel–biodiesel blend

International Nuclear Information System (INIS)

Rashedul, H.K.; Masjuki, H.H.; Kalam, M.A.; Teoh, Y.H.; How, H.G.; Rizwanul Fattah, I.M.

2015-01-01

Highlights: • Alexandrian laurel or Calophyllum inophyllum biodiesel blend fulfill the ASTM (D7467) specification. • Addition of antioxidant to biodiesel higher the oxidation stability. • Antioxidant treated blends showed lower NO X and BSFC compared to untreated blend. • Antioxidant treated blends showed higher CO, HC and smoke compared to untreated blend. - Abstract: Alexandrian laurel or Calophyllum inophyllum oil is recently considered one of the most anticipated nonconsumable or nonedible biodiesel sources. An attempt has been made in this study to increase the oxidation stability and investigate the engine performance, emission, and combustion characteristics of a diesel engine by adding 1% (by vol.) of two antioxidants, such as 2,6-Di-tert.-butyl-4-methylphenol and 2,2′-methylenebis (4-methyl-6-tert-butylphenol), in higher percentages of C. inophyllum biodiesel (CB30) with diesel fuel (B0). The experiment was performed on a single-cylinder, water-cooled, direct-injection diesel engine for this purpose. The addition of both antioxidants increased the oxidation stability without significantly changing other physicochemical properties. Results also show that the antioxidants enhanced the start of combustion of biodiesel, which resulted in a short ignition delay. The peak pressure and the peak heat release rate during premixed combustion phase of pure CB30 and its modified blend with antioxidant were higher than those of B0. Both antioxidant blends showed higher brake power, higher brake thermal efficiency, and lower brake specific fuel consumption than pure CB30. Both antioxidants significantly reduced NO X emission; however, CO, HC, and smoke opacity were slightly higher than those of CB30. Based on this study, Alexandrian laurel or C. inophyllum biodiesel blend (CB30) with antioxidant can be used as an alternative fuel in a diesel engine without modifications.

Properties of rubber blends based on natural rubber loaded with different fillers and cured by gamma radiation

International Nuclear Information System (INIS)

Mohamed, R.M.

2011-01-01

In this investigation system styrene butadiene rubber (1502 type) and natural rubber were blended in different ratios namely, NR/SBR (0/100), NR/SBR (25/75), NR/SBR (50/50), NR/SBR (75/25) and NR/SBR (100/0). All the samples were subjected to gamma irradiation dose up to 250 kGy. The improvement in the mechanical properties, physico-mechanical properties and thermal properties was followed as a function of irradiation dose and blend ratio. The SBR /NR (50/50) blend with reasonable properties were filled with 40 p hr of Hisil (highly fined silicon), HAF carbon black (high abrasion furnace), TiO 2 titanium dioxide and clay; the reinforcing ability of these fillers was found to follow the order: Hisil > HAF carbon black > Clay > TiO 2 The effect of different kinds of enhancing agents (coagent) namely: N, N- methylene di acrylamide (MDA), trimethylol propane tri methacrylate (TMPTMA) and tetramethylol - methane tetraacrylate (TMMT) on the properties of the obtained composites as a function of irradiation dose was studied. The data obtained showed that the enhancement character of the co agents follow the order: TMMT >TMPTMA > MDA >unenhanced composites. This investigation showed also the effect of gamma irradiation on improving the above mentioned properties in the presence of filler and co agents. Moreover, radiation dose at 100 kGy is sufficient enough for obtained the desired properties. The obtaining composites can be used in many industrial applications such as radio controlled model race car tires to footwear applications; the SBR component adds the toughness while the natural rubber provides superior resilience and energy return when used in footwear.

Effect of hydrostatic pressure on the structural and electronic properties of Cd{sub 0.75}Cr{sub 0.25}S

Energy Technology Data Exchange (ETDEWEB)

Rani, Anita [Guru Nanak College for Girls, Sri Muktsar Sahib Punjab-152026 (India); Kaur, Kulwinder; Kumar, Ranjan [Department of Physics, Panjab University Chandigarh-160014 (India); Dhiman, Shobna [Department of Applied Science, PEC, University of Technology, Chandigarh-160011 (India)

2016-05-23

In this paper we present the results obtained from first principle calculations of the effect of hydrostatic pressure on the structural and electronic properties of Cd{sub 1-x}Cr{sub x}S diluted magnetic semiconductor in Zinc Blende (B3) phase at x=0.25. High pressure behavior of Cd{sub 1-x}Cr{sub x}S has been investigated between 0 GPa to 100 GPa The calculations have been performed using Density functional theory as implemented in the Spanish Initiative for Electronic Simulations with Thousands of Atoms code using local density approximation as exchange-correlation (XC) potential. Calculated electronic band structures of Cd{sub 1-x}Cr{sub x}S are discussed in terms of contribution of Cr 3d{sup 5} 4s{sup 1}, Cd 4d{sup 10} 5s{sup 2}, S 3s{sup 2} 3p{sup 4} orbital’s. Study of band structures shows half-metallic ferromagnetic nature of Cd{sub 0.75}Cr{sub 0.25}S with 100% spin polarization. Under application of external pressure, the valence band and conduction band are shifted upward which leads to modification of electronic structure.

Degradation assessment of natural weathering on low density polyethylene/thermoplastic soya spent powder blends

Science.gov (United States)

Nuradibah, M. A.; Sam, S. T.; Noriman, N. Z.; Ragunathan, S.; Ismail, H.

2015-07-01

Soya spent powder was blended with low density polyethylene (LDPE) ranging from 5-25 wt%. Glycerol was added to soya spent powder (SSP) for preparation of thermoplastic soya spent powder (TSSP). Then, the blends were exposed to natural weathering for 6 months. The susceptibility of the LDPE/soya spent powder blends based on its tensile, morphological properties and structural changes was measured every three months. The tensile strength of LDPE/TSSP blends after 6 months of weathering was the lowest compared to the other blends whereas LDPE/SSP blends after 6 months of weathering demonstrated the lowest elongation at break (Eb). Large pore can be seen on the surface of 25 wt% of LDPE/SSP blends.

Performance and emission characteristics of diesel engine with COME-Triacetin additive blends as fuel

Energy Technology Data Exchange (ETDEWEB)

Venkateswara Rao, P. [Dept. of Mechanical Engineering, K I T S, Warangal- 506015, A. P. (India); Appa Rao, B.V. [Dept. of Marine Engineering, Andhra University, Visakhapatnam-530003, A. P. (India)

2012-07-01

The Triacetin [C9H14O6] additive is used an anti-knocking agent along with the bio-diesel in DI- diesel engine. In the usage of diesel fuel and neat bio-diesel knocking can be detected to some extent. The T- additive usage in the engine suppressed knocking, improved the performance and reduced tail pipe emissions. Comparative study is conducted using petro-diesel, bio-diesel, and with various additive blends of bio-diesel on DI- diesel engine. Coconut oil methyl ester (COME) is used with additive Triacetin (T) at various percentages by volume for all loads (No load, 25%, 50%, 75% and full load). The performance of engine is compared with neat diesel in respect of engine efficiency, exhaust emissions and combustion knock. Of the five Triacetin- biodiesel blends tried, 10% Triacetin combination with biodiesel proved encouraging in all respects of performance of the engine.

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%.

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

African Journals Online (AJOL)

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

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 of a diesel engine with methyl ester of mango seed oil and diesel blends

Directory of Open Access Journals (Sweden)

K. Vijayaraj

2016-03-01

Full Text Available Petroleum based fuels worldwide have not only resulted in the rapid depletion of conventional energy sources, but have also caused severe air pollution. The search for an alternate fuel has led to many findings due to which a wide variety of alternative fuels are available at our disposal now. The existing studies have revealed the use of vegetable oils for engines as an alternative for diesel fuel. However, there is a limitation in using straight vegetable oils in diesel engines due to their high viscosity and low volatility. In the present work, neat mango seed oil is converted into their respective methyl ester through transesterification process. Experiments are conducted using various blends of methyl ester of mango seed oil with diesel in a single cylinder, four stroke vertical and air cooled Kirloskar diesel engine. The experimental results of this study showed that the MEMSO biodiesel has similar characteristics to those of diesel. The brake thermal efficiency, unburned hydrocarbon and smoke density are observed to be lower in case of MEMSO biodiesel blends than diesel. The CO emission for B25, B50 and B75 is observed to be lower than diesel at full load, whereas for B100 it is higher at all loads. On the other hand, BSFC and NOx of MEMSO biodiesel blends are found to be higher than diesel. It is found that the combustion characteristics of all blends of methyl ester of mango seed oil showed similar trends with those of the baseline diesel. From this study, it is concluded that optimized blend is B25 and could be used as a viable alternative fuel in a single cylinder direct injection diesel engine without any modifications.

Combined effect of nanoemulsion and EGR on combustion and emission characteristics of neat lemongrass oil (LGO)-DEE-diesel blend fuelled diesel engine

International Nuclear Information System (INIS)

Sathiyamoorthi, R.; Sankaranarayanan, G.; Pitchandi, K.

2017-01-01

Highlights: • Neat lemongrass oil can be used as an alternate fuel in diesel engine. • The combined effect of nano emulsion and EGR using LGO25-DEE-Diesel is investigated. • The BTE is improved for nano emulsion fuel blend. • The NO_x and smoke emissions decrease significantly. • Cylinder pressure and Heat release rate increase with longer ignition delay. - Abstract: In the present experimental study, the combined effects of nanoemulsion and exhaust gas recirculation (EGR) on the performance, combustion and emission characteristics of a single cylinder, four stroke, variable compression ratio diesel engine fueled with neat lemongrass oil (LGO)-diesel-DEE (diethyl ether) blend are investigated. The Neat Lemongrass oil could be used as a new alternate fuel in compression ignition engines without any engine modifications. The entire investigation was conducted in the diesel engine using the following test fuels: emulsified LGO25, cerium oxide blended emulsified LGO25 and DEE added emulsified LGO25 with EGR respectively and compared with standard diesel and LGO25 (75% by volume of diesel and 25% by volume of lemongrass oil) fuels. The combined effect of DEE added nano-emulsified LGO25 with EGR yielded a significant reduction in NO_x and smoke emission by 30.72% and 11.2% respectively compared to LGO25. Furthermore, the HC and CO emissions were reduced by 18.18% and 33.31% respectively than with LGO25. The brake thermal efficiency and brake specific fuel consumption increased by 2.4% and 10.8% respectively than LGO25. The combustion characteristics such as cylinder pressure and heat release rate increased by 4.46% and 3.29% respectively than with LGO25. The combustion duration and ignition delay increase at nano-emulsified LGO25 with DEE and EGR mode but decrease for nano-emulsified LGO25 fuel.

Density-functional theory computer simulations of CZTS0.25Se0.75 alloy phase diagrams

International Nuclear Information System (INIS)

Chagarov, E.; Sardashti, K.; Kummel, A. C.; Haight, R.; Mitzi, D. B.

2016-01-01

Density-functional theory simulations of CZTS, CZTSe, and CZTS 0.25 Se 0.75 photovoltaic compounds have been performed to investigate the stability of the CZTS 0.25 Se 0.75 alloy vs. decomposition into CZTS, CZTSe, and other secondary compounds. The Gibbs energy for vibrational contributions was estimated by calculating phonon spectra and thermodynamic properties at finite temperatures. It was demonstrated that the CZTS 0.25 Se 0.75 alloy is stabilized not by enthalpy of formation but primarily by the mixing contributions to the Gibbs energy. The Gibbs energy gains/losses for several decomposition reactions were calculated as a function of temperature with/without intermixing and vibration contributions to the Gibbs energy. A set of phase diagrams was built in the multidimensional space of chemical potentials at 300 K and 900 K temperatures to demonstrate alloy stability and boundary compounds at various chemical conditions. It demonstrated for CZTS 0.25 Se 0.75 that the chemical potentials for stability differ between typical processing temperature (∼900 K) and operating temperature (300 K). This implies that as cooling progresses, the flux/concentration of S should be increased in MBE growth to maintain the CZTS 0.25 Se 0.75 in a thermodynamically stable state to minimize phase decomposition.

Density-functional theory computer simulations of CZTS0.25Se0.75 alloy phase diagrams

Science.gov (United States)

Chagarov, E.; Sardashti, K.; Haight, R.; Mitzi, D. B.; Kummel, A. C.

2016-08-01

Density-functional theory simulations of CZTS, CZTSe, and CZTS0.25Se0.75 photovoltaic compounds have been performed to investigate the stability of the CZTS0.25Se0.75 alloy vs. decomposition into CZTS, CZTSe, and other secondary compounds. The Gibbs energy for vibrational contributions was estimated by calculating phonon spectra and thermodynamic properties at finite temperatures. It was demonstrated that the CZTS0.25Se0.75 alloy is stabilized not by enthalpy of formation but primarily by the mixing contributions to the Gibbs energy. The Gibbs energy gains/losses for several decomposition reactions were calculated as a function of temperature with/without intermixing and vibration contributions to the Gibbs energy. A set of phase diagrams was built in the multidimensional space of chemical potentials at 300 K and 900 K temperatures to demonstrate alloy stability and boundary compounds at various chemical conditions. It demonstrated for CZTS0.25Se0.75 that the chemical potentials for stability differ between typical processing temperature (˜900 K) and operating temperature (300 K). This implies that as cooling progresses, the flux/concentration of S should be increased in MBE growth to maintain the CZTS0.25Se0.75 in a thermodynamically stable state to minimize phase decomposition.

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

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)

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

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.

The Effect of Gamma Irradiation on the Mechanical Properties of vulcanized Natural Rubber and Natural Rubber-Polyethylene Blends

International Nuclear Information System (INIS)

Sudradjat Iskandar

2008-01-01

To enhance the quality of vulcanized natural rubber and natural rubber-polyethylene blends, gamma irradiation has been done. The compound of natural rubber and natural rubber-polyethylene blends made by using roll mill machine. The mixed materials were antioxidant, anti ozon, plasticizer and vulcanisator. The natural rubber and natural rubber-polyethylene blends compound were vulcanizer and made a slab (film of sample) using hot and could press machine. The slabs produced were then gamma irradiated at irradiation dose of 75, 150 and 300 kGy. Before and after irradiation, the slab were characterized using strograph R1 machine. The results showed that the modulus 300 and hardness of vulcanized natural rubber and natural rubber-polyethylene blends were increasing; the tensile strength and tear strength were increasing to maximum level then decreasing with gamma irradiation, while the elongation at break was decreasing. The maximum tensile strength of vulcanized natural rubber and natural rubber-polyethylene blends were found at irradiation dose of 75 kGy. At the irradiation dose of 75 kGy, the tensile strength of vulcanized natural rubber increased from 17.6 MN/m 2 to 21.2 MN/m 2 , while the tensile strength of vulcanized natural rubber-polyethylene blends increased slightly from 18.7 MN/m 2 to 19.4 MN/m 2 . (author)

Investigation of miscibility of p(3hydroxybutyrate-co-3hydroxyhexanoate) and epoxidized natural rubber blends

Science.gov (United States)

Akram, Faridah; Chan, Chin Han; Natarajan, Valliyappan David

2015-08-01

Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate [P(3HB-co-3HHx)] produced by C. necator PHB-4 harboring phaCcs from crude palm kernel oil with 21 mol% of 3-hydroxyhexanoate and epoxidized natural rubber with 25 mol% of epoxy content (ENR-25) were used to study the miscibility of the blends by attenuated total reflection-Fourier transform infrared (ATR-FTIR) and differential scanning calorimetry (DSC). The polymers used were purified and the blends were prepared by solution casting method. Nuclear magnetic resonance (NMR) spectra confirm the purity and molecular structures of P(3HB-co-3HHx) and ENR-25. FTIR spectra for different compositions of P(3HB-co-3HHx) and ENR-25 blends show absorbance change of the absorbance bands but with no significant shifting of the absorbance bands as the P(3HB-co-3HHx) content decreases, which shows that there is no intermolecular interaction between the parent polymer blends. On top of that, there are two Tgs present for the blends and both remain constant for different compositions which corresponds to the Tgs of the parent polymers. This indicates that the blends are immiscible.

Study of exhaust emissions of direct injection diesel engine operating on ethanol, petrol and rapeseed oil blends

International Nuclear Information System (INIS)

Labeckas, Gvidonas; Slavinskas, Stasys

2009-01-01

This article presents the bench testing results of a four stroke, four cylinder, direct injection, unmodified, diesel engine operating on pure rapeseed oil (RO) and its 2.5 vol%, 5 vol%, 7.5 vol% and 10 vol% blends with ethanol (ERO), petrol (PRO) and both improving agents applied in equal proportions as 50:50 vol% (EPRO). The purpose of the research is to examine the effect of ethanol and petrol addition into RO on diesel engine emission characteristics and smoke opacity of the exhausts. The biggest NO x emissions, 1954 and 2078 ppm, at 2000 min -1 speed generate blends PRO10 (9.72%) and EPRO5 (11.13%) against, 1731 and 1411 ppm, produced from ERO5 (12%) and ERO10 (13.2% oxygen) blends. The carbon monoxide, CO, emissions emitted from a fully loaded engine fuelled with three agent blends EPRO5-7.5 at maximum torque and rated speed are higher by 39.5-18.8% and 27.5-16.1% and smoke opacity lower by 3.3-9.0% and 24.1-17.6% comparing with RO case. When operating at rated 2200 min -1 mode, the carbon dioxide, CO 2 , emissions are lower, 6.9-6.3 vol%, from blends EPRO5-7.5 relative to that from RO, 7.8 vol%, accompanied by a slightly higher emission of unburned hydrocarbons HC, 16 ppm, and residual oxygen contents O 2 , 10.4-12.0 vol%, in the exhausts

Studies on the hypolipidemic effects of Coconut oil when blended with Tiger nut oil and fed to albino rats

Directory of Open Access Journals (Sweden)

El-Anany, A. M.

2012-09-01

Full Text Available Hyperlipidemia is a predominant risk factor for atherosclerosis and associated cardiovascular diseases (CVD. The international guidelines issued by the World Health Organization recommend a reduction in dietary saturated fat and cholesterol intake as a means to prevent hypercholesterolemia and CVD. The main objective of the current investigation was to evaluate the effects of feeding blended oils consisting of coconut oil (CNO with different proportions of Tiger nut oil (TNO on serum lipid levels in Albino rats. GLC analysis was performed to illustrate the fatty acid composition of the blended oils. Blended oils were obtained by mixing tiger nut oil with coconut oil at the volume ratios of 100:0, 70:30, 50:50, 25:75, 10:90 and 0:100. Fifty-six male albino rats were randomly divided into 7 groups of 8 rats each according to the oil type. The blended oils were fed to rats for a period of up to 10 weeks. Total cholesterol (T-Ch, high-density lipoprotein cholesterol (HDL-Ch, low-density lipoprotein cholesterol (LDL-Ch, and triglycerides (TG, were determined. The atherogenic Index (AI was calculated. The results showed that non-significant changes in all nutritional parameters were observed between the control group and the rats fed with the tested oils. The results also indicate that coconut oil had 86% saturated fatty acids. On TNO contains 66% oleic acid. Therefore, blending coconut oil with tiger nut oil can reduce the proportions of saturated to unsaturated fatty acids in CNO. The rats that were fed blended oils showed significantly reduced levels of serum cholesterol as compared to those fed CNO. The HDL levels were marginally enhanced in the rats that were fed blended oils. The total cholesterol and LDL cholesterol levels were controlled when TNO/CNO proportions varied between 25/75 and 70/30. This was reflected in the calculation of the atherogenic index. Similar changes were observed with serum triglyceride levels.

La hiperlipidemia

Optimization of hybrid polymer electrolytes with the effect of lithium salt concentration in PEO/PVdF-HFP blends

Energy Technology Data Exchange (ETDEWEB)

Pradeepa, P.; Edwin raj, S.; Sowmya, G.; Kalaiselvimary, J.; Ramesh Prabhu, M., E-mail: mkram83@gmail.com

2016-03-15

Highlights: • Polymer blends based on PVdF-HFP/PEO were prepared for Li-ion battery applications. • Structural and electrochemical studies were carried out on prepared electrolytes. • The electrolytes can be used as electrolyte in the possible device fabrications. - Abstract: Poly(ethylene oxide) (PEO) 6.25 wt%/poly(vinylidene fluoride-co-hexafluoropropylene) [P(VdF-HFP)] 18.75 wt% blend based electrolyte films containing different concentrations (2–10) wt% of lithium salt were prepared. The miscibility studies have been performed by using X-ray diffraction and Fourier transform infrared spectroscopy. The role of interaction between polymer hosts on conductivity is discussed using the results of a.c. impedance studies. A room temperature conductivity of 2.3912 × 10{sup −4} S cm{sup −1} has been obtained for PEO (6.25)–PVdF-HFP (18.75)–LiClO{sub 4} (8)–PC (67) polymer complex. The temperature dependence of the conductivity of polymer electrolyte seems to obey VTF relation. Electrochemical stability (3.3 V) was observed in the prepared polymer electrolyte. Reduction process and oxidation process of the prepared electrolyte system have also been evaluated by means of cyclic voltammetry. Thermogravimetric analysis results indicate thermal stability of PEO/PVdF-HFP lithium salt complexes. Roughness parameter of the sample having maximum ionic conductivity was studied by AFM. The morphology of the polymer complex is investigated by using SEM.

Thermal behavior and kinetics assessment of ethanol/gasoline blends during combustion by thermogravimetric analysis

International Nuclear Information System (INIS)

3, CEP 12.516-410 Guaratinguetá, SP (Brazil); U.T.P. – Universidad Tecnológica de Pereira, Faculty of Mechanical Engineering, Pereira, Risaralda (Colombia))" data-affiliation=" (UNESP – Univ Estadual Paulista, Campus of Guaratinguetá, Department of Energy, Laboratory of Combustion and Carbon Capture LC3, CEP 12.516-410 Guaratinguetá, SP (Brazil); U.T.P. – Universidad Tecnológica de Pereira, Faculty of Mechanical Engineering, Pereira, Risaralda (Colombia))" >Rios Quiroga, Luis Carlos; 3, CEP 12.516-410 Guaratinguetá, SP (Brazil))" data-affiliation=" (UNESP – Univ Estadual Paulista, Campus of Guaratinguetá, Department of Energy, Laboratory of Combustion and Carbon Capture LC3, CEP 12.516-410 Guaratinguetá, SP (Brazil))" >Balestieri, José 3, CEP 12.516-410 Guaratinguetá, SP (Brazil))" data-affiliation=" (UNESP – Univ Estadual Paulista, Campus of Guaratinguetá, Department of Energy, Laboratory of Combustion and Carbon Capture LC3, CEP 12.516-410 Guaratinguetá, SP (Brazil))" >Antonio Perrella; 3, CEP 12.516-410 Guaratinguetá, SP (Brazil))" data-affiliation=" (UNESP – Univ Estadual Paulista, Campus of Guaratinguetá, Department of Energy, Laboratory of Combustion and Carbon Capture LC3, CEP 12.516-410 Guaratinguetá, SP (Brazil))" >Ávila, Ivonete

2017-01-01

Highlights: • Kinetic parameters of thermal decomposition events were obtained. • Thermal analysis was used as a tool for understanding combustion processes. • Blends would be classified using thermogravimetric analysis technics. • Synergistic effect of ethanol mixed with gasoline was studied and defined. • Relative error and activation energy values were used to analyze the synergy. - Abstract: The use of ethanol as a fuel or as an additive blended with gasoline is very important for most countries, which aim to reduce the heavy dependence on fossil fuels and mitigate greenhouse gases emission. An increased use of ethanol-gasoline blends has placed great relevance on acquiring knowledge about their physical and chemical properties. Thus, knowledge of such properties favors a better understanding of the effect of the percentage of ethanol/gasoline blends on engine performance. Thence, the present study has established a correlation between activation energy and synergetic effects, obtained by a thermal analysis, and ethanol content in gasoline for different blends in order to use this technique as a tool to classify these blends in the process in order to obtain useful energy in spark ignition engines. For such a purpose, a kinetic study has been conducted through a simultaneous thermal analysis system – TGA (thermogravimetry analysis) and DTA (differential thermal analysis) by following the methodology of non-isothermal tests. Thermogravimetric tests were performed and fuel activation energies for gasoline, ethanol, and percentages of 5, 10, 15, 20, 25, 30, 50, and 75% (%v) ethanol mixed with gasoline, which was achieved by the model free kinetics. The analysis results suggest that the theoretical curves characteristics of the thermal decomposition of ethanol-gasoline blends are rather different due to their ethanol content. Furthermore, it was observed significant interactions and synergistic effects, especially regarding those with low ethanol

Na1.25Ni1.25Fe1.75(PO4)3 nanoparticles as a janus electrode material for Li-ion batteries

Science.gov (United States)

Karegeya, Claude; Mahmoud, Abdelfattah; Hatert, Frédéric; Vertruyen, Bénédicte; Cloots, Rudi; Lippens, Pierre-Emmanuel; Boschini, Frédéric

2018-06-01

A solvothermal method was used to prepare Na1.25Ni1.25Fe1.75(PO4)3 nanoparticles, a new promising electrode material for lithium-ion batteries. The composition and the crystal structure were determined by 57Fe Mössbauer spectroscopy and powder X-ray diffraction Rietveld refinements and confirmed by magnetic measurements. The structural formula □0.75Na1.25Ni1.25Fe1.75(PO4)3 was obtained showing a significant amount of Na vacancies, which enhances Li diffusion. Na1.25Ni1.25Fe1.75(PO4)3 was used as negative and positive electrode material and shows excellent electrochemical performances. As negative electrode in the voltage range 0.03-3.5 V vs. Li+/Li, the first discharge at current density of 40 mA g-1 delivers a specific capacity of 1186 mAh g-1, which is almost three times its theoretical capacity (428 mAh g-1). Then, reversible capacity of 550 mAh g-1 was obtained at 50 mA g-1 with high rate capability (150 mAh g-1 at 500 mA g-1) and capacity retention of 350 cycles. As positive electrode material, specific capacities of about 145 and 99 mAh g-1 were delivered at current densities of 5 and 50 mA g-1, respectively, in the voltage range of 1.5-4.5 V vs. Li+/Li. In addition, we show that the use of solvothermal synthesis contributes to the synthesis of small sized particles leading to good electrochemical performances.

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)

33 CFR 159.307 - Untreated sewage.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Untreated sewage. 159.307 Section 159.307 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Operations § 159.307 Untreated sewage. No person shall discharge any untreated sewage from a cruise vessel...

[Effect of extrusion on protein and starch bioavailability in corn and lima bean flour blends].

Science.gov (United States)

Pérez-Navarrete, Cecilia; Betancur-Ancona, David; Casotto, Meris; Carmona, Andrés; Tovar, Juscelino

2007-09-01

Extrusion is used to produce crunchy expanded foods, such as snacks. The nutritional impact of this process has not been studied sufficiently. In this study, in vitro and in vivo protein and starch bioavailability was evaluated in both raw and extruded corn (Zea mays)(C) and lima bean (Phaseolus lunatus)(B) flour blends, prepared in 75C/25B and 50C/ 50B (p/p) proportions. These were processed with a Brabender extruder at 160 degrees C, 100 rpm and 15.5% moisture content. Proximate composition showed that in the extruded products protein and ash contents increased whereas the fat level decreased. In vitro protein digestibility was higher in the extrudates (82%) than in the raw flours (77%). Potentially available starch and resistant starch contents decreased with extrusion. The in vitro assays indicated that extrusion improved protein and starch availability in the studied blends. In vivo bioavailability was evaluated using the rice weevil (Sithophilus oryzae) as a biological model. The most descriptive biomarkers of the changes suggested by the in vivo tests were body protein content (increased by extrusion) and intestinal a-amylase activity (decreased by processing). Overall, results suggest that extrusion notably increases the nutritional quality of corn and lima bean flour blends.

Investigation of miscibility of p(3hydroxybutyrate-co-3hydroxyhexanoate) and epoxidized natural rubber blends

Energy Technology Data Exchange (ETDEWEB)

Akram, Faridah; Chan, Chin Han; Natarajan, Valliyappan David [Faculty of Applied Sciences, Universiti Teknologi MARA, Shah Alam, 40450 Selangor Darul Ehsan (Malaysia)

2015-08-28

Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate [P(3HB-co-3HHx)] produced by C. necator PHB{sup −}4 harboring phaC{sub cs} from crude palm kernel oil with 21 mol% of 3-hydroxyhexanoate and epoxidized natural rubber with 25 mol% of epoxy content (ENR-25) were used to study the miscibility of the blends by attenuated total reflection-Fourier transform infrared (ATR-FTIR) and differential scanning calorimetry (DSC). The polymers used were purified and the blends were prepared by solution casting method. Nuclear magnetic resonance (NMR) spectra confirm the purity and molecular structures of P(3HB-co-3HHx) and ENR-25. FTIR spectra for different compositions of P(3HB-co-3HHx) and ENR-25 blends show absorbance change of the absorbance bands but with no significant shifting of the absorbance bands as the P(3HB-co-3HHx) content decreases, which shows that there is no intermolecular interaction between the parent polymer blends. On top of that, there are two T{sub g}s present for the blends and both remain constant for different compositions which corresponds to the T{sub g}s of the parent polymers. This indicates that the blends are immiscible.

Investigation of miscibility of p(3hydroxybutyrate-co-3hydroxyhexanoate) and epoxidized natural rubber blends

International Nuclear Information System (INIS)

Akram, Faridah; Chan, Chin Han; Natarajan, Valliyappan David

2015-01-01

Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate [P(3HB-co-3HHx)] produced by C. necator PHB − 4 harboring phaC cs from crude palm kernel oil with 21 mol% of 3-hydroxyhexanoate and epoxidized natural rubber with 25 mol% of epoxy content (ENR-25) were used to study the miscibility of the blends by attenuated total reflection-Fourier transform infrared (ATR-FTIR) and differential scanning calorimetry (DSC). The polymers used were purified and the blends were prepared by solution casting method. Nuclear magnetic resonance (NMR) spectra confirm the purity and molecular structures of P(3HB-co-3HHx) and ENR-25. FTIR spectra for different compositions of P(3HB-co-3HHx) and ENR-25 blends show absorbance change of the absorbance bands but with no significant shifting of the absorbance bands as the P(3HB-co-3HHx) content decreases, which shows that there is no intermolecular interaction between the parent polymer blends. On top of that, there are two T g s present for the blends and both remain constant for different compositions which corresponds to the T g s of the parent polymers. This indicates that the blends are immiscible

Predictors of untreated dental decay among 15-34-year-old Australians.

Science.gov (United States)

Jamieson, Lisa M; Mejía, Gloria C; Slade, Gary D; Roberts-Thomson, Kaye F

2009-02-01

To determine predictors of untreated dental decay among 15-34-year-olds in Australia. Data were from Australia's National Survey of Adult Oral Health, a representative survey that utilized a three-stage, stratified clustered sampling design. Models representing demographic, socioeconomic, dental service utilization and oral health perception variables were tested using multivariable logistic regression to produce odds ratios. An estimated 25.8% (95% CI 22.4-29.5) of 15-34-year-old Australians had untreated dental decay. After controlling for other covariates, those who lived in a location other than a capital city had 2.0 times the odds of having untreated dental decay than their capital city-dwelling counterparts (95% CI 1.29-3.06). Similarly, those whose highest level of education was not a university degree had 2.1 times the odds of experiencing untreated dental decay (95% CI 1.35-3.31). Perceived need of extractions or restorations predicted untreated coronal decay, with 2.9 times the odds for those who perceived a treatment need over those with no such treatment need perception (95% CI 1.84-4.53). Participants who experienced dental fear had 2.2 times the odds of having untreated dental decay (95% CI 1.38-3.41), while those who reported experiencing toothache, orofacial pain or food avoidance in the last 12 months had 1.9 times the odds of having untreated dental decay than their counterparts with no such oral health-related quality-of-life impact (95% CI 1.20-2.92). The multivariate model achieved a 'useful' level of accuracy in predicting untreated decay (area under the ROC curve = 0.74; sensitivity = 0.63; specificity = 0.73). In the Australian young adult population, residential location, education level, perceived need for dental care, dental fear, toothache, orofacial pain or food avoidance together were predictors of untreated dental decay. The prediction model had acceptable specificity, indicating that it may be useful as part of a triage system for

Preparation of the PET/PP/PE/EVA polymeric blend from PET bottles and modification studies induced by ionizing radiation

International Nuclear Information System (INIS)

Rossini, Edvaldo Luis

2005-01-01

The environmental pollution is one of the biggest problems nowadays. Amidst the pollutants, plastic and especially the packings type P ET bottles , which comprise of poly(ethylene terephthalate) (PET), polypropylene (PP), polyethylene (PE) and poly[ethylene-co-(vinyl acetate)] (EVA) are causing big damage in the environment. In this work, the polymeric blend PET/PP/PE/EVA was obtained by a process of simplified mechanical recycling from 'PET bottles' after consumption, with the objective to find solution to this environmental problem. It was also studied the different ionizing radiation doses effects (25, 50, 75, 100, 150, 200, 300, 400 e 500 kGy) on the blend properties using an electron beam accelerator. The mechanical (tensile strength, impact and hardness), thermal (Vicat softening temperature, differential scanning calorimetry and termogravimetric) and microscopic (light microscopy and scanning electron microscopy) properties of the blend were studied. The analysis of the results showed to be a not mixing and compatible blend, with mechanical and thermal properties (which appeared to be similar to the properties of the component material used in the blend in separate) satisfactory, resulting in a resistant material and of low cost, being able to be used in the production of parts that do not demand specifications techniques. The use of the ionizing radiation improved some of the mechanical and thermal properties of the blend (these modifications had been random and irregular, depending directly on the dose of applied radiation and the type of property) making possible more specific applications for this material. (author)

Remodelación del probador de aceites WPOT 0.25/75; Remodelig of the WPOT0.25/75 oil tester

Directory of Open Access Journals (Sweden)

Ignat Pérez Almirall

2011-02-01

Full Text Available El objetivo fundamental de este trabajo es el rediseño del probador de aceites WPOT 0.25/75. Para estofue necesario rediseñar completamente todo su sistema de control y de protección pues el original ademásde estar constituido sobre la base de válvulas de vacío, no funcionaba ya que presentaba fallas en lossoportes aislantes de las mismas, fallas de dichas válvulas y fallas en la placa aislante que sirve desoporte a los componentes de los mecanismos de protección y control. Para solucionar estos problemasse diseñó un sistema de control con tiristores para la protección del equipo sustituyéndose por completoel obsoleto sistema de control a válvulas, lográndose un sistema de control seguro, confiable y de fáciloperación como para ser operado por personal con pocas habilidades.  The main objective of this paper is to remodel the WPOT 0.25/75 oil tester equipment. The originalequipment was made with vacuum valves, coupled on an insulated support. This equipment presentedseveral electrical failures on the insulated support and in the vacuum valves. In order to solve this problem,a new control and protecting system, using tiristor,  was designed . With this new design it was possibleto use this oil tester again. Moreover, the design offers better and new operating options useful for somespecial interesting tests.

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...

Evaluation of untreated dental caries in children with PUFA index

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Nagehan Aktaş

2018-01-01

Full Text Available Objective: Tooth decay continues to come up as a serious health problem particularly in developing countries. Limited number of studies investigated the prevalence of complication of untreated dental caries as abscess, fistula and ulceration. The purpose of the present study was to investigate the prevalence of the clinical consequences of untreated dental caries among a group of children. Materials and Method: The study was conducted on 1200 children with ages between 5-12 years in the Department of Pedodontics, Faculty of Dentistry, GaziUniversity between the dates 1-31 March 2012. Caries in deciduous and permanent teeth were scored using DMFT/dmft and PUFA/pufa indexes (D/d: decayed, M/m: missing, F/f: filled, P/p: carious lesion with pulpal involvement, U/u: ulceration of the mucosa due to root fragments, F/f: fistula, A/a: abscess. Results: DMFT index was 2.34 ± 1.37 and dmft index was 4.25 ± 3.46. The prevalence of PUFA/pufa for permanent and deciduous teeth was 2.30% and 22.25%, respectively. The highest score in both permanent and deciduous teeth was caries lesions with pulpal involvement (%11.24 for deciduous teeth and %1.67 for permanent teeth. This was followed by abscess and fistula formation. Conclusion: The prevalence of clinical consequences of untreated dental caries was high for deciduous teeth in the selected population. The PUFA/pufa index is seen as an epidemiological tool complementary to the existing caries index aimed to assess dental caries.

Evaluation of salt, polyphosphates and their blends at different levels on physicochemical properties of buffalo meat and patties.

Science.gov (United States)

Anjaneyulu, A S; Sharma, N; Kondaiah, N

1989-01-01

The effects of sodium pyrophosphate (SPP), sodium tripolyphosphate (STPP), sodium hexametaphosphate (SHMP), sodium acid pyrophosphate (SAPP) and their blends at different levels (0·3, 0·5 and 0·7%), along with 2% sodium chloride on certain quality parameters of buffalo meat and patties were evaluated. The SPP, STPP and phosphate blends significantly increased pH, water-holding capacity (WHC), emulsifying capacity (EC), extractability of salt soluble proteins (SSP), colour of ground meat, decreased cooking loss (CL), improved emulsion stability (ES) and enhanced yield, texture and moisture retention of cooked patties. Compared to these phosphates, SAPP and SHMP had significantly poorer effects on improving the quality of meat and patties. The order of effectiveness of phosphates was SPP > STPP > SHMP. In general, pH, WHC, SSP, ES, yield and moisture content of patties increased progressively with increasing level of phosphate while CL decreased. Among blends containing two polyphosphates, those of 90% SPP + 10% SHMP and 75% SPP + 25% STPP were relatively more effective. A phosphate blend consisting of 65% SPP, 17·5% STPP and 17·5% SAPP was equally effective as that of SPP in improving the functionality of hot and chilled meat and had the advantage of reducing the amount of sodium by 3%. Copyright © 1989. Published by Elsevier Ltd.

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.

Contrasting effects of untreated textile wastewater onto the soil available nitrogen-phosphorus and enzymatic activities in aridisol.

Science.gov (United States)

Arif, Muhammad Saleem; Riaz, Muhammad; Shahzad, Sher Muhammad; Yasmeen, Tahira; Buttler, Alexandre; Garcıa-Gil, Juan Carlos; Roohi, Mahnaz; Rasool, Akhtar

2016-02-01

Water shortage and soil qualitative degradation are significant environmental problems in arid and semi-arid regions of the world. The increasing demand for water in agriculture and industry has resulted in the emergence of wastewater use as an alternative in these areas. Textile wastewater is produced in surplus amounts which poses threat to the environment as well as associated flora and fauna. A 60-day incubation study was performed to assess the effects of untreated textile wastewater at 0, 25, 50, 75, and 100% dilution levels on the physico-chemical and some microbial and enzymatic properties of an aridisol soil. The addition of textile wastewater provoked a significant change in soil pH and electrical conductivity and soil dehydrogenase and urease activities compared to the distilled-water treated control soil. Moreover, compared to the control treatment, soil phosphomonoesterase activity was significantly increased from 25 to 75% application rates, but decreased at 100% textile wastewater application rate. Total and available soil N contents increased significantly in response to application of textile wastewater. Despite significant increases in the soil total P contents after the addition of textile wastewater, soil available P content decreased with increasing concentration of wastewater. Changes in soil nutrient contents and related enzymatic activities suggested a dynamic match between substrate availability and soil N and P contents. Aridisols have high fixation and low P availability, application of textile wastewater to such soils should be considered only after careful assessment.

Experimental investigations on a CRDI system assisted diesel engine fuelled with aluminium oxide nanoparticles blended biodiesel

Directory of Open Access Journals (Sweden)

C. Syed Aalam

2015-09-01

Full Text Available Experiments were conducted to determine engine performance, exhaust emissions and combustion characteristics of a single cylinder, common rail direct injection (CRDI system assisted diesel engine using diesel with 25 percentage of zizipus jujube methyl ester blended fuel (ZJME25. Along with this ZJME25 aluminium oxide nanoparticles were added as additive in mass fractions of 25 ppm (AONP 25 and 50 ppm (AONP 50 with the help of a mechanical Homogenizer and an ultrasonicator. It was observed that aluminium oxide nanoparticles blended fuel exhibits a significant reduction in specific fuel consumption and exhaust emissions at all operating loads. At the full load, the magnitude of HC and smoke emission for the ZJME25 before the addition of aluminium oxide nanoparticles was 13.459 g/kW h and 79 HSU, whereas it was 8.599 g/kW h and 49 HSU for the AONP 50 blended ZJME25 fuel respectively. The results also showed a considerable enhancement in brake thermal efficiency and heat release rate due to the influence of aluminium oxide nanoparticles addition in biodiesel–diesel blend.

Density-functional theory computer simulations of CZTS{sub 0.25}Se{sub 0.75} alloy phase diagrams

Energy Technology Data Exchange (ETDEWEB)

Chagarov, E.; Sardashti, K.; Kummel, A. C. [Departments of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093 (United States); Haight, R. [IBM T. J. Watson Research Center, P.O. Box 218, Yorktown Heights, New York 10598 (United States); Mitzi, D. B. [Departments of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708 (United States)

2016-08-14

Density-functional theory simulations of CZTS, CZTSe, and CZTS{sub 0.25}Se{sub 0.75} photovoltaic compounds have been performed to investigate the stability of the CZTS{sub 0.25}Se{sub 0.75} alloy vs. decomposition into CZTS, CZTSe, and other secondary compounds. The Gibbs energy for vibrational contributions was estimated by calculating phonon spectra and thermodynamic properties at finite temperatures. It was demonstrated that the CZTS{sub 0.25}Se{sub 0.75} alloy is stabilized not by enthalpy of formation but primarily by the mixing contributions to the Gibbs energy. The Gibbs energy gains/losses for several decomposition reactions were calculated as a function of temperature with/without intermixing and vibration contributions to the Gibbs energy. A set of phase diagrams was built in the multidimensional space of chemical potentials at 300 K and 900 K temperatures to demonstrate alloy stability and boundary compounds at various chemical conditions. It demonstrated for CZTS{sub 0.25}Se{sub 0.75} that the chemical potentials for stability differ between typical processing temperature (∼900 K) and operating temperature (300 K). This implies that as cooling progresses, the flux/concentration of S should be increased in MBE growth to maintain the CZTS{sub 0.25}Se{sub 0.75} in a thermodynamically stable state to minimize phase decomposition.

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.

Strain effects on electronic structure of Fe{sub 0.75}Ru{sub 0.25}Te

Energy Technology Data Exchange (ETDEWEB)

Winiarski, M.J., E-mail: M.Winiarski@int.pan.wroc.pl [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Okólna 2, 50-422, Wrocław (Poland); Samsel-Czekała, M. [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Okólna 2, 50-422, Wrocław (Poland); Ciechan, A. [Institute of Physics, Polish Academy of Sciences, al. Lotników 32/46, 02-668, Warsaw (Poland)

2017-01-15

Structural and electronic properties of a hypothetical Fe{sub 0.75}Ru{sub 0.25}Te alloy and the parent FeTe compound have been investigated from first principles within the density functional theory (DFT). For both systems the double-stripe antiferromagnetic ground state is predicted at ambient pressure. The incorporation of Ru atoms into FeTe in the nonmagnetic phase leads to a deep valley of density of states in the vicinity of the Fermi level and the DOS at the Fermi level is significantly diminished in the considered solid solution. The single-stripe antiferromagnetic phase in Fe{sub 0.75}Ru{sub 0.25}Te may be induced by tensile strain. These findings suggest that strained thin films of Fe{sub 1−x}Ru{sub x}Te are good candidates for new superconducting Fe-based materials. - Highlights: • Ru-doped FeTe systems are investigated by density-functional theory methods. • Structural and electronic properties of Fe{sub 0.75}Ru{sub 0.25}Te and parent FeTe are studied. • The double-stripe antiferromagnetic ground state is predicted for both systems. • The single-stripe antiferromagnetic phase may be induced by tensile strain. • Tensile strained Fe{sub 0.75}Ru{sub 0.25}Te is a candidate for a new Fe-based superconductor.

Effect of the gamma radiation in the properties of PEBD / amphiprotic starch blend

International Nuclear Information System (INIS)

Texeira, Magno F.H.B.I.; Caetano, Viviane F.; Ferreira, Flavia G.D.; Almeida, Yeda M.B. de; Vinhas, Gloria M.

2009-01-01

The degradation of the polyethylene of low density (PEBD) it can be accelerated through the addition of natural polymer, minimizing the impact caused by the residues discarded in the environment. In this work the effect of the radiation gamma was evaluated in the PEBD / amphiprotic starch blend, in the doses of 25, 60 and 120 kGy. This blend after exposed to gamma radiation was analyzed by differential scanning calorimeter (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and mechanical properties. The blends after irradiation in the doses of 60 and 25 kGy had not presented change in the melting point temperature. Already the blends radiated in the dose of 120 kGy presented two melting point temperatures. Through the analyses in the infrared was detected the presence of the group carbonyl and primary and secondary alcohols as a result of the structural alteration in function of the radiolytic degradation. In the mechanical rehearsals, the blends presented decrease in the specific deformation in the rupture and in the module of elasticity when irradiated in the doses of 25, 60 and 120 kGy, respectively. Already the tension results in the rupture stayed practically unaffected with the effect of the gamma radiation. (author)

Experimental investigation of performance and regulated emissions of a diesel engine with Calophyllum inophyllum biodiesel blends accompanied by oxidation inhibitors

International Nuclear Information System (INIS)

Rizwanul Fattah, I.M.; Masjuki, H.H.; Kalam, M.A.; Wakil, M.A.; Ashraful, A.M.; Shahir, S.A.

2014-01-01

Highlights: • Calophyllum inophyllum biodiesel blends were evaluated using antioxidants. • Blend fuel properties met the ASTM D7467 specification. • Usage of antioxidants provided good stabilization with improved BP and BSFC. • Treated blends showed lower NOx but higher CO and HC compared to untreated blend. - Abstract: Biodiesel having higher unsaturation possesses lower oxidation stability, which needs treatment of oxidation inhibitors or antioxidants. It is expected that antioxidants may affect the clean burning characteristic of biodiesel. Calophyllum inophyllum Linn oil is one of the promising non-edible based feedstock which consists of mostly unsaturated fatty acids. This paper presents an experimental investigation of the antioxidant addition effect on engine performance and emission characteristics. Biodiesel (CIBD) was produced by one step esterification using sulfuric acid (H 2 SO 4 ) as catalyst and one step transesterification using potassium hydroxide (KOH) as a catalyst. Two monophenolic, 2(3)-tert-Butyl-4-methoxyphenol (BHA) and 2,6-di-tert-butyl-4-methylphenol (BHT) and one diphenolic, 2-tert-butylbenzene-1,4-diol (TBHQ) were added at 2000 ppm concentration to 20% CIBD (CIB20). The addition of antioxidants increased oxidation stability without causing any significant negative effect of physicochemical properties. TBHQ showed the greatest capability in increasing stability of CIB20. The tests were carried out using a 55 kW 2.5 L four-cylinder diesel engine at constant load varying speed condition. The performance results indicate that CIB20 showed 1.36% lower mean brake power (BP) and 4.90% higher mean brake specific fuel consumption (BSFC) compared to diesel. The addition of antioxidants increased BP and reduced BSFC slightly. Emission results show that CIB20 increased NOx but decreased CO and HC emission. Antioxidants reduced 1.6–3.6% NOx emission, but increased both CO and HC emission compared to CIB20. However, the level was below the

Facile preparation of novel organic–inorganic PI/Zn0.25Cd0.75S composite for enhanced visible light photocatalytic performance

International Nuclear Information System (INIS)

Yan, Tao; Li, Mengmeng; Wang, Xiaodong; Sun, Meng; Liu, Hongye; Wei, Qin; Xu, Wenguo; Du, Bin

2015-01-01

Graphical abstract: - Highlights: • Novel PI/Zn 0.25 Cd 0.75 S composite showed enhanced activity in dye degradation. • The composites PIZCS-30 exhibited the best activity. • The heterojunction was in situ fabricated between PI and Zn 0.25 Cd 0.75 S. • The PI/Zn 0.25 Cd 0.75 S heterojunction facilitated the separation of electron–hole pairs. - Abstract: Novel organic–inorganic polyimide (PI)–Zn 0.25 Cd 0.75 S composites with high-efficiency visible light performance was prepared by a facile and template free hydrothermal method. The obtained composites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photo-electron spectroscopy (XPS), ultraviolet–visible diffuse reflection spectroscopy (DRS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The XRD and SEM results revealed that the PI exhibited a high degree of polymerization. The DRS characterization showed that the light absorption exhibited regular shifts upon the change of PI/Zn 0.25 Cd 0.75 S mass ratio. The TEM results proved the in situ growth of finely distributed Zn 0.25 Cd 0.75 S nanoparticles on the surface of PI sheets. The as-prepared samples exhibited superior photocatalytic activity compared with PI and Zn 0.25 Cd 0.75 S toward the degradation of dyes under visible light irradiation. The electrochemical impedance spectroscopy (EIS) confirmed that the separation efficiency of electron–hole pairs was greatly improved for the formation of heterojunction. The activity enhancement of PI/Zn 0.25 Cd 0.75 S composites could be attributed to the interfacial electronic interaction and high migration efficiency of photo-induced carriers. A possible photodegradation mechanism was proposed for the degradation of dyes over PI/Zn 0.25 Cd 0.75 S composites

The study of untreated syphilis in the Negro male

International Nuclear Information System (INIS)

Brawley, Otis W.

1998-01-01

Purpose: The participation of minorities in clinical studies is the subject of much discussion and has even become the subject of Federal law. The project known as the Tuskegee Syphilis Study and officially titled 'The Tuskegee Study of Untreated Syphilis in the Negro Male', is one of the great debacles of American medicine and a national shame. Despite the fact that its existence is well known, many do not know the historical facts of the study nor the context of the study. My purpose here is to recount the facts of the study and its historical context. Methods: The history recounted here is taken from documents gathered during a U.S. Senate investigation of the study, original papers located in National Library of Medicine, and books about the trial. Results: The trial began in 1931 as a survey of the natural history of untreated tertiary syphilis in Black men. This study enrolled 399 men with syphilis and 201 uninfected men to serve as controls. All were at least 25 years old at enrollment. The men were told they were in a study, but never educated about the implications. Later, men were not informed that there was a treatment for effective treatment for their disease - a treatment that was being withheld from them. This trial continued till 1972. Conclusion: Many of the issues that led to the study and caused it to continue for 40 years still exist. The lessons of the Public Health Study of Untreated Syphilis in the Untreated Negro include the dangers of paternalism, arrogance, blind loyalty, and misuse of science. 'Those who do not appreciate history are condemned to repeat it' (Alfred North Whitehead)

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)

Synthesis of Pt{sub 75}Sn{sub 25}/SnO{sub 2}/CNT nanoscaled electrode: Low onset potential of ethanol electrooxidation

Energy Technology Data Exchange (ETDEWEB)

Tabet-Aoul, Amel [Institut National de la Recherche Scientifique (INRS)-Énergie, Matériaux et Télécommunications (EMT), 1650 Boulevard Lionel Boulet, Varennes, Québec, Canada J3X 1S2 (Canada); Mohamedi, Mohamed, E-mail: mohamedi@emt.inrs.ca [Institut National de la Recherche Scientifique (INRS)-Énergie, Matériaux et Télécommunications (EMT), 1650 Boulevard Lionel Boulet, Varennes, Québec, Canada J3X 1S2 (Canada)

2013-03-15

Highlights: ► A pulsed laser synthesis is used for the deposition of Pt, SnO{sub 2} and PtSn alloy thin films onto carbon nanotubes. ► These nanoscaled materials were characterized by FESEM, TEM, XRD and XPS. ► Enhanced electrocatalytic properties toward ethanol oxidation. -- Abstract: With the objective of lowering the potential oxidation of ethanol at PtSn nanocatalyst, we present the synthesis of free-standing catalyst layer comprising a current collector/carbon nanotubes (catalyst support)/SnO{sub 2}/Pt{sub 75}Sn{sub 25} (catalyst) nanostructured layers, each layer constructed upon the one below it. The CNTs are grown by chemical vapor deposition (CVD), whereas SnO{sub 2} and Pt{sub 75}Sn{sub 25} are synthesized by pulsed laser deposition and cross-beam laser deposition, respectively. FESEM revealed that Pt{sub 75}Sn{sub 25} nanoparticles assemble into cauliflower-like arrangement. TEM and HR-TEM showed that the Pt{sub 75}Sn{sub 25} layer thickness is of ca. 25 nm with a particle mean diameter of 4.3 nm. It was found that addition of SnO{sub 2} to Pt{sub 75}Sn{sub 25} promotes significantly the oxidation of ethanol at Pt{sub 75}Sn{sub 25} nanoparticles relative to a carbon nanotubes support. Indeed, the electrooxidation of ethanol at CNTs/SnO{sub 2}/Pt{sub 75}Sn{sub 25} electrode starts at about 100 mV negative with respect to that at CNT/Pt{sub 75}Sn{sub 25}. This decreased overpotential required to oxidize ethanol is very significant and has profound implications to developing high performing anodes for direct ethanol fuel cells technology.

Novel poly(vinylidene fluoride-trifluoroethylene)/poly(ethylene oxide) blends for battery separators in lithium-ion applications

International Nuclear Information System (INIS)

Costa, C.M.; Nunes-Pereira, J.; Rodrigues, L.C.; Silva, M.M.; Ribelles, J.L. Gomez; Lanceros-Méndez, S.

2013-01-01

Highlights: ► New P(VDF-TrFE)/PEO polymer blends were prepared for battery separator. ► The porosity and hydrophilicity degree are tailored within this blend. ► Ionic conductivity depends on PEO presence and is stable with temperature. ► High ionic conductivity of 0.25 mS cm −1 for the 60/40 blend. -- Abstract: Polymer blends based on poly(vinylidene fluoride-trifluoroethylene)/poly(ethylene oxide), P(VDF-TrFE)/PEO for Li-ion battery separator applications have been prepared through solvent casting technique. The microstructure, hydrophilicity and electrolyte uptake strongly depend on PEO content within the blend. The best value of ionic conductivity at room temperature was 0.25 mS cm −1 for the 60/40 membrane. The membranes are electrochemically stable

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.

Altered metabolic incorporation of fucose and leucine into PNS myelin of 25-week-old diabetic (C57BL/Ks [db/db]) mice: effects of untreated diabetes on nerve metabolism

International Nuclear Information System (INIS)

Chez, M.G.; Peterson, R.G.

1983-01-01

Sciatic nerves of 25-week-old genetically diabetic (C57BL/Ks [db/db]) mice and their litter-mate controls were removed, and their metabolic incorporation of [ 3 H]fucose and [ 14 C]leucine into myelin was studied in vitro. Untreated diabetic animals showed significant increases (p less than 0.05) in the fucose/leucine incorporation into myelin when compared to values found for their litter-mates. These results correlated well with previous experiments performed on alloxan or streptozotocin-diabetic rats and thus show the in vitro incubation procedure to be a good indicator of altered metabolic conditions in peripheral nerves due to diabetes mellitus. The resulting ratio increases seen in diabetic animals is at variance with the decrease in ratios found in animals undergoing typical Wallerian degeneration. These results suggest that different metabolic processes operate in untreated diabetics than in normals or in those undergoing other degenerative nerve processes

Stability and electronic properties of Cd0.75Mn0.25S and Cd0.75Mn0.25Se in B3 phase

Energy Technology Data Exchange (ETDEWEB)

Rani, Anita [Guru Nanak College for Girls, Sri Muktsar Sahib, Punjab (India); Kumar, Ranjan [Panjab University, Department of Physics, Chandigarh (India)

2015-08-15

We studied the structural, elastic, spin-polarized electronic band structures and magnetic properties of the diluted magnetic semiconductor Cd{sub 1-x}Mn{sub x}S and Cd{sub 1-x} Mn{sub x}Se in zinc blende phase (B3) for x = 0.25 using ab initio method. The calculations were performed by using density functional theory as implemented in the Spanish Initiative for Electronic Simulations with Thousands of Atoms code using local density approximation. Calculated electronic band structures and magnetic properties of Cd{sub 1-x}Mn{sub x}S are discussed in terms of contribution of Mn 3d{sup 5} 4s{sup 2}, Cd 4d{sup 10} 5s{sup 2}, S 3s{sup 2} 3p{sup 4} orbitals. The total magnetic moment is found to be 5.00 μ{sub b} for Cd{sub 1-x}Mn{sub x}S and Cd{sub 1-x}Mn{sub x}Se at x = 0.25. This value indicates that Mn atom adds no hole carrier to the perfect CdS crystal. We determine the spin-exchange splitting energies produced by Mn 3d states, s-d exchange constant N{sub 0}α, and p-d exchange constant N{sub 0}β. We found that Mn-doped systems are ferromagnetic. Calculated results are in good agreement with previous studies. (orig.)

Ultrafast quasiparticle dynamics of FeTe0.75Se0.25 superconductor

Directory of Open Access Journals (Sweden)

Katagiri T.

2013-03-01

Full Text Available The electron-phonon coupling constant (λ≈0.45 obtained from femtosecond pump-probe reflection measurements suggests that a phonon-mediated process cannot be the dominant mechanism for superconductivity of FeTe0.75Se0.25.

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.

Effect of Babassu Natural Filler on PBAT/PHB Biodegradable Blends: An Investigation of Thermal, Mechanical, and Morphological Behavior

Directory of Open Access Journals (Sweden)

Vinicius C. Beber

2018-05-01

Full Text Available Blending of biodegradable polymers in combination with low-price organic fillers has proven to be a suitable approach to produce cost-effective composites in order to address pollution issues and develop products with superior mechanical properties. In the present research work PBAT/PHB/Babassu composites with 25, 50, and 75% of each polymer and 20% of Babassu were produced by melting extrusion. Their thermal, mechanical, and morphological behavior was investigated by differential scanning calorimetry (DSC, tensile testing, and scanning electron microscopy (SEM. Blending PBAT with PHB inhibited the crystallization of both polymers whereas adding Babassu did not significantly change their melting behaviour. Incorporation of Babassu reduced the tensile strength of its respective blends between 4.8 and 32.3%, and elongation at break between 26.0 and 66.3%. PBAT as highly ductile and low crystalline polymer may be seen as a crystallization tool control for PHB as well as a plasticizer to PBAT/PHB blends and PBAT/PHB/Babassu composites. As PBAT content increases: (i elongation at break increases and (ii surface fracture becomes more refined indicating the presence of more energy dissipation mechanisms. As PBAT/PHB/Babassu composites are biodegradable, environmental friendly, and cost effective, products based on these compounds have a great potential since their mechanical properties such as ductility, stiffness, and tensile strength are still suitable for several applications even at lower temperatures (−40 °C.

STUDY ON POZZOLANA ACTIVITY OF WHEAT STRAW ASH AS POTENTIAL ADMIXTURE FOR BLENDED CEMENTS

Directory of Open Access Journals (Sweden)

Ondrej Jankovsky

2017-09-01

Full Text Available Wheat straw ash coming from combustion of packed wheat straw was studied as a potential pozzolana active admixture for blended cements. X-Ray fluorescence, X-Ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy were used to examine chemical and mineralogical composition, morphology and elemental distribution of a raw untreated ash. Due to high carbon content, the wheat straw ash was thermally treated for 2 hours at 700 °C and analyzed again using the same analytic techniques. Thermal treatment process was monitored using simultaneous thermal analysis and Fourier Transform infrared spectroscopy. The pozzolana activity was assessed using Chapelle and Frattini tests. In the next step, wheat straw ash was used for preparation of blended cement pastes. The content of ash in the blends was 10, 15, and 20% by mass. For the hardened pastes, basic physical properties, mechanical parameters, and pore size distribution were measured. For fresh past mixes, workability was tested. Moreover, leachability of chlorides, nitrates, sulfates and alkalis from paste samples was studied. The experimentally obtained data pointed to the high pozzolana activity of wheat straw ash and sufficient mechanical properties of cement pastes with the ash content up to 20 mass% of cement. In summary, the analyzed waste product from biomass combustion was found to be applicable as a part of cement-based blended binder providing economic and environmental benefits for concrete industry.

An experimental study of the combusition and emission performances of 2,5-dimethylfuran diesel blends on a diesel engine

Directory of Open Access Journals (Sweden)

Xiao Helin

2017-01-01

Full Text Available Experiments were carried out in a direct injection compression ignition engine fueled with diesel-dimethylfuran blends. The combustion and emission performances of diesel-dimethylfuran blends were investigated under various loads ranging from 0.13 to 1.13 MPa brake mean effective pressure, and a constant speed of 1800 rpm. Results indicate that diesel-dimethylfuran blends have different combustion performance and produce longer ignition delay and shorter combustion duration compared with pure diesel. Moreover, a slight increase of brake specific fuel consumption and brake thermal efficiency occurs when a Diesel engine operates with blended fuels, rather than diesel fuel. Diesel-dimethylfuran blends could lead to higher NOx emissions at medium and high engine loads. However, there is a significant reduction in soot emission when engines are fueled with diesel-dimethylfuran blends. Soot emissions under each operating conditions are similar and close to zero except for D40 at 0.13 MPa brake mean effective pressure. The total number and mean geometric diameter of emitted particles from diesel-dimethylfuran blends are lower than pure diesel. The tested fuels exhibit no significant difference in either CO or HC emissions at medium and high engine loads. Nevertheless, diesel fuel produces the lowest CO emission and higher HC emission at low loads of 0.13 to 0.38 MPa brake mean effective pressure.

Behavior Characteristics of Type I (75/25) Octol during Melt Pouring HE Warhead M250 (Chaparral)

Science.gov (United States)

1979-09-01

COVERED BEHAVIOR CHARACTERISTICS OF TYPE 1 (75/25) "OCTOL DURING MELT POURING HE WARHEAD I M250 (CHAPARRAL) 6. PERFORMING ORG. APrPORT NUMBER 7. AUTHOR...Military Specification, HMX, MIL-H-45444B, Amendment 2, dated 12 July 1977. 4 6. Military Specification, Warhead, Guided Missile, HE, M250 , Loading...CHARACTERISTICS OF TYPE i (75/25) OCTOL DURING MELT POURING HE WARHEAD M250 (CHAPARRAL) HERMAN J. FRIGAND SEPTEMBER 1979 US ARMY ARMAMENT RESEARCH AND

MISCIBILITY AND THERMAL DEGRADATION KINETICS OF POLY-β-ALANINE/POLY(3-HYDROXYPROPIONATE BLENDS

Directory of Open Access Journals (Sweden)

Efkan CATIKER

2016-11-01

Full Text Available Poly-β-alanine (PBA and poly(3-hidroxypropionate (PHP were synthesized via base-catalyzed hydrogen transfer polymerization (HTP of acrylamide and acrylic acid, respectively. Blends of PBA/PHP with different composition (PHP content, 5% to 75% were studied using FTIR, DSC, TGA, XRD and polarized optical microscope to reveal both miscibility and thermal degradation kinetics of PBA/PHP blends.  Optical images of blends were transparent and entirely uniform. Characteristic IR bands of both components shifted in higher frequencies with increasing fraction of other component.  Melting temperature (Tm, thermal decomposition temperatures (Td and enthalpy of fusion (ΔHf of PHP decreased with increasing PBA fraction in blends. Thermal degradation kinetics of both components were studied by Freeman-Carroll method. Activation energies of thermal degradations of blend components were determined with a good regression coefficients (at least 0.994. Activation energies of decomposition decreased from 224.14 to 86.125 kJmol-1 with increasing PHP content. XRD spectra of blends exhibited lower peak intensities than those of neat polymers. The spectroscopic, thermal and optic methods revealed that PBA and PHP were miscible with a good compatibility in amorphous phase.

Lead titanate/cyclic carbonate dependence on ionic conductivity of ferro/acrylate blend polymer composites

Energy Technology Data Exchange (ETDEWEB)

Jayaraman, R. [Department of Physics, GTN Arts and Science College, Dindigul (India); Vickraman, P., E-mail: vrsvickraman@yahoo.com; Subramanian, N. M. V.; Justin, A. Simon [Department of Physics, Gandhigram Rural Institute- Deemed University, Gandhigram (India)

2016-05-23

Impedance, XRD, DSC and FTIR studies had been carried out for PVdF-co-HFP/LIBETI based system for three plasticizer (EC/DMC) – filler (PbTiO3) weight ratios. The enhanced conductivity 4.18 × 10{sup −5} Scm{sup −1} was noted for 57.5 wt% −7.5 wt% plasticizer – filler. while blending PEMA to PVdF-co-HFP respectively 7.5: 22.5 wt % (3/7), 15 wt%: 15 wt % (5/5) and 22.5wt %: 7.5 wt % (7/3), the improved conductivity was noted for 3/7 ratio 1.22 × 10{sup −5} S cm{sup −1} and its temperature dependence abide Arrhenius behavior. The intensity of peaks in XRD diffractogram registered dominance of lead titanate, from 2θ = 10° to 80° and absence of VdF crystallites (α+β phase) was noted. In DSC studies, the presence of the exotherm events, filler effect was distinctively seen exhibiting recrystallization of VdF crystallites. In blending PEMA, however, no trace of exotherms was found suggestive of PEMA better inhibiting recrystallization. FTIR study confirmed molecular interactions of various constituents in the vibrational band 500 – 1000 cm{sup −1} both in pristine PVdF-co-HFP and PEMA blended composites with reference to C-F stretching, C-H stretching and C=O carbonyl bands.

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...

Improved permeation performance and fouling-resistance of Poly(vinyl chloride/Polycarbonate blend membrane with added Pluronic F127

Directory of Open Access Journals (Sweden)

Supateekan Pacharasakoolchai

2014-04-01

Full Text Available The aim of this work was to prepare and characterize poly(vinyl chloride (PVC/polycarbonate (PC blend membranes for use in ultrafiltration. Pluronic F127 was used as an additive to modify the membrane surface of the PVC/PC blended membranes. The PVC/PC blend membrane was first prepared using the phase inversion method from a casting solution of PVC with small amount of PC in N-methylpyrrolidone (NMP and water as the non-solvent. The morphologies structure and properties, such as tensile strength, water flux, and bovine serum albumin (BSA rejection of the blend membrane were studied. Increased amounts of PC resulted in an increase in the water flux and ability to reject protein. A concentration of 0.75 wt% PC provided the best improvement in tensile strength of blend membrane. Addition of different amounts of pluronic F127 to the casting solution of PVC/PC with a PC concentration of 0.75 wt% resulted in a decrease in the water contact angle that demonstrated the improvement of hydrophilicity of blend membrane. Scanning electron microscopy photographs showed that the modified PVC/PC membranes had a bigger pore volume in the porous sub-layer compared to the PVC/PC control membrane. The PVC/PC membrane with added Pluronic F127 exhibited a much higher flux and rejection of BSA in a protein filtration experiment than the PVC/PC membrane. An increase in flux recovery ratio of PVC/PC/pluronic 127 blend membrane indicated that the modified membranes could reduce membrane fouling useful for ultrafiltration.

Physical stability of API/polymer-blend amorphous solid dispersions.

Science.gov (United States)

Lehmkemper, Kristin; Kyeremateng, Samuel O; Bartels, Mareike; Degenhardt, Matthias; Sadowski, Gabriele

2018-03-01

The preparation of amorphous solid dispersions (ASDs) is a well-established strategy for formulating active pharmaceutical ingredients by embedding them in excipients, usually amorphous polymers. Different polymers can be combined for designing ASDs with desired properties like an optimized dissolution behavior. One important criterion for the development of ASD compositions is the physical stability. In this work, the physical stability of API/polymer-blend ASDs was investigated by thermodynamic modeling and stability studies. Amorphous naproxen (NAP) and acetaminophen (APAP) were embedded in blends of hydroxypropyl methylcellulose acetate succinate (HPMCAS) and either poly(vinylpyrrolidone) (PVP) or poly(vinylpyrrolidone-co-vinyl acetate) (PVPVA64). Parameters for modeling the API solubility in the blends and the glass-transition temperature curves of the water-free systems with Perturbed-Chain Statistical Associating Fluid Theory and Kwei equation, respectively, were correlated to experimental data. The phase behavior for standardized storage conditions (0%, 60% and 75% relative humidity (RH)) was predicted and compared to six months-long stability studies. According to modeling and experimental results, the physical stability was reduced with increasing HPMCAS content and increasing RH. This trend was observed for all investigated systems, with both APIs (NAP and APAP) and both polymer blends (PVP/HPMCAS and PVPVA64/HPMCAS). PC-SAFT and the Kwei equation turned out to be suitable tools for modeling and predicting the physical stability of the investigated API/polymer-blends ASDs. Copyright © 2017 Elsevier B.V. All rights reserved.

The Effect of Ethanol-Diesel Blends on The Performance of A Direct Injection Diesel Engine

Directory of Open Access Journals (Sweden)

Arifin Nur

2012-07-01

Full Text Available The experiment was conducted on a conventional direct injection diesel engine. Performance test was carried out to evaluate the performance and emission characteristics of a conventional diesel engine that operates on ethanol-diesel blends. The test procedure was performed by coupling the diesel engine on the eddy current dynamometer. Fuel consumption was measured using the AVL Fuel Balance, and a hotwire anemometer was used to measure the air consumption. Some of the emission test devices were mounted on the exhaust pipe. The test of fuel variations started from 100% diesel fuel (D100 to 2.5% (DE2.5, 5% (DE5, 7.5% (DE7.5, and 10% (DE10 ethanol additions. Performance test was conducted at 1500 rpm with load variations from 0 to 60 Nm by increasing the load on each level by 10 Nm. The addition of 5% ethanol to diesel (DE5 increased the average pressure of combustion chamber indication to 48% as well as reduced the specific fuel consumption to 9.5%. There were better exhaust emission characteristics at this mixture ratio than diesel engine which used pure diesel fuel (D100, the reduction of CO to 37%, HC to 44% and opacity to 15.9%.

Subretinal lipid exudation associated with untreated choroidal melanoma

Directory of Open Access Journals (Sweden)

C K Minija

2011-01-01

Full Text Available Subretinal lipid exudation in an untreated choroidal melanoma is very rare. It is seen following plaque radiotherapy in choroidal melanoma. There is only one case report of untreated choroidal melanoma with massive lipid exudation in a patient with metastatic hypernephroma. We report here a rare case of untreated choroidal melanoma with lipid exudation. Subretinal exudation that is rarely seen following plaque brachytherapy was noted at the borders of this untreated tumor. Lipid exudation partially resolved following brachytherapy.

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

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

Supporting School Leaders in Blended Learning with Blended Learning

Science.gov (United States)

Acree, Lauren; Gibson, Theresa; Mangum, Nancy; Wolf, Mary Ann; Kellogg, Shaun; Branon, Suzanne

2017-01-01

This study provides a mixed-methods case-study design evaluation of the Leadership in Blended Learning (LBL) program. The LBL program uses blended approaches, including face-to-face and online, to prepare school leaders to implement blended learning initiatives in their schools. This evaluation found that the program designers effectively…

Structural and dynamical heterogeneity of undercooled Fe{sub 75}Cu{sub 25} melts with miscibility gap

Energy Technology Data Exchange (ETDEWEB)

Qi, Yu; Wang, Li; Wang, Shenghai, E-mail: shenghaiw@163.com; Li, Xuelian; Cui, Wenchao

2014-12-05

Highlights: • We simulate the undercooled Fe{sub 75}Cu{sub 25} melts with miscibility gap at atomic level. • Fe{sub 75}Cu{sub 25} melts separate into Cu-rich and Fe-rich liquid upon relaxation. • The process is controlled by the nucleation and grows mechanism. • Both PPCFs and CN confirm that L–L phase separation is a successive process. - Abstract: Molecular dynamics simulation (MD) based upon the developed embedded atom method (EAM) has been performed to explore the structural and dynamical heterogeneity of Fe{sub 75}Cu{sub 25} melts. The results show that the melts separate into Cu-rich droplets surround by the Fe-rich matrix controlled by nucleation and growth mechanism. The larger undercoolings suggest the higher nucleation rate and growth rate of droplets. The growth of droplet is achieved by the aggregation and coagulation of neighbor droplet with the characteristics of collective movement for homogeneous atoms. A sharp increase of S{sub CC} (q = 0) is found at all simulated temperature, which means concentration fluctuation on large length scales are much pronounced. Both partial pair correlation functions (PPCFs) and coordination number (CN) confirm that liquid–liquid (L–L) phase separation is a successive process with a stronger interaction of homogeneous pairs than that of heterogeneous pairs in Fe{sub 75}Cu{sub 25} melts. The studies above characterize the phase separation of metal melts on the atomic scale.

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.

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.

Magnetic and magnetocaloric properties of HoCr0.75Fe0.25O3 compound

Science.gov (United States)

Kotnana, Ganesh; Babu, P. D.; Jammalamadaka, S. Narayana

2018-05-01

We report on the magnetic and magnetocaloric properties of HoCr0.75Fe0.25O3 compound around the Néel temperature (TN), which is due to Cr3+ ordering. Susceptibility (χ) vs. temperature (T) graph of HoCr0.75Fe0.25O3 compound infer two transitions due to the ordering of Cr3+ moments (TN ˜ 155 K) and Ho3+ moments (TNHo ˜ 8 K). Magnetic entropy (-ΔSM) value of 1.14 J kg-1 K-1 around 157.5 K with a magnetic field (H) of 90 kOe is attributed to antiferromagnetic (AFM) ordering of Cr3+ moments. A maximum value of adiabatic temperature (ΔTad) ˜ 0.41 K around TN is obtained and is found to increases with applied magnetic field. Negative slope for H/M vs. M2 graph is evident for HoCr0.75Fe0.25O3 compound below TN, which indicates the first order phase transition. Quantified values of -ΔSM and ΔTad open the way to explore rare earth orthochromites for the MCE properties and refrigeration applications.

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

First-principles calculations of a half-metallic ferromagnet zinc blende Zn1−xVxTe

International Nuclear Information System (INIS)

El Amine Monir, M.; Baltache, H.; Khenata, R.; Murtaza, G.; Azam, Sikander; Bouhemadou, A.; Al-Douri, Y.; Bin Omran, S.; Ali, Roshan

2015-01-01

First-principles calculations have been used to study the structural, elastic, electronic, magnetic and thermal properties of zinc blende Zn 1−x V x Te for x=0, 0.25, 0.50, 0.75 and 1 using the full-potential linearized augmented plane wave method (FP-LAPW) based on spin-polarized density functional theory (DFT). The electronic exchange-correlation potential is approached using the spin generalized gradient approximation (spin-GGA). The structural properties of the Zn 1−x V x Te alloys (x=0, 0.25, 0.50, 0.75 and 1) are given for the lattice constants and the bulk moduli and their pressure derivatives. The elastic constants C 11 , C 12 and C 44 are calculated using numerical first-principles calculations implemented in the WIEN2k package. An analysis of the band structures and the densities of states reveals that Zn 0.50 V 0.50 Te and Zn 0.75 V 0.25 Te exhibit a half-metallic character, while Zn 0.25 V 0.75 Te is nearly half-metallic. The band structure calculations are used to estimate the spin-polarized splitting energies Δ x (d) and Δ x (pd) produced by the V(3d)-doped and s(p)–d exchange constants N 0α (conduction band) and N 0β (valence band). The p–d hybridization reduces the magnetic moment of V from its atomic charge value of 3µ B and creates small local magnetic moments on the nonmagnetic Zn and Te sites. Finally, we present the thermal effect on the macroscopic properties of these alloys, such as the thermal expansion coefficient, heat capacity and Debye temperature, based on the quasi-harmonic Debye model. - Highlights: • Some physical properties of Vanadium doped ZnTe have been investigated. • Structural parameters for the parent compounds compare well with the available data. • The elastic and thermal properties are studied for the first time

Combustion performance evaluation of air staging of palm oil blends.

Science.gov (United States)

Mohd Jaafar, Mohammad Nazri; Eldrainy, Yehia A; Mat Ali, Muhammad Faiser; Wan Omar, W Z; Mohd Hizam, Mohd Faizi Arif

2012-02-21

The problems of global warming and the unstable price of petroleum oils have led to a race to develop environmentally friendly biofuels, such as palm oil or ethanol derived from corn and sugar cane. Biofuels are a potential replacement for fossil fuel, since they are renewable and environmentally friendly. This paper evaluates the combustion performance and emission characteristics of Refined, Bleached, and Deodorized Palm Oil (RBDPO)/diesel blends B5, B10, B15, B20, and B25 by volume, using an industrial oil burner with and without secondary air. Wall temperature profiles along the combustion chamber axis were measured using a series of thermocouples fitted axially on the combustion chamber wall, and emissions released were measured using a gas analyzer. The results show that RBDPO blend B25 produced the maximum emission reduction of 56.9% of CO, 74.7% of NOx, 68.5% of SO(2), and 77.5% of UHC compared to petroleum diesel, while air staging (secondary air) in most cases reduces the emissions further. However, increasing concentrations of RBDPO in the blends also reduced the energy released from the combustion. The maximum wall temperature reduction was 62.7% for B25 at the exit of the combustion chamber.

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.

Analysis of LaNi4.25Al0.75 (LANA.75) tritide after five years of tritium exposure

International Nuclear Information System (INIS)

Wermer, J.R.; Holder, J.S.; Mosley, W.C.

1993-01-01

Tritium aging studies have shown that LaNi 4.25 Al 0.75 (LANA .75) tritide storage material undergoes significant degradation with tritium aging. After 5.4 years of dormant storage at full stoichiometry, which is considered a worst-case condition for this material, the performance is still acceptable for SRS tritium processing applications. The isotherms change, decreasing the desorption pressures, increasing the isotherm plateau slopes, and decreasing the total storage capacity. Eventually, the material will degrade with time to the point where it may no longer be useful for tritium processing applications. At the end of life, the tritium heel can be exchanged with protium or deuterium to produce a final material containing very little tritium

EXPERIMENTAL INVESTIGATIONS ON THE EFFECT OF HYDROGEN INDUCTION ON PERFORMANCE AND EMISSION BEHAVIOUR OF A SINGLE CYLINDER DIESEL ENGINE FUELLED WITH PALM OIL METHYL ESTER AND ITS BLEND WITH DIESEL

Directory of Open Access Journals (Sweden)

BOOPATHI D.

2017-07-01

Full Text Available Internal combustion engines are an integral part of our daily lives, especially in the agricultural and transportation sector. With depleting fossil fuel and increasing environmental pollution, the researchers are foraying into alternate sources for fuelling the internal combustion engine. Vegetable oils derived from plant seeds is one such solution, but using them in unmodified diesel engine leads to reduced thermal efficiency and increased smoke emissions. Hydrogen if induced in small quantities in the air intake manifold can enhance the engine performance running on biodiesel. In this work, experiments were performed to evaluate the engine performance when hydrogen was inducted in small quantities and blends of esterified palm oil and diesel was injected as pilot fuel in the conventional manner. Tests were performed on a single cylinder, 4 - stroke, water cooled, direct injection diesel engine running at constant speed of 1500 rpm under variable load conditions and varying hydrogen flow. At full load for 75D25POME (a blend of 75% diesel and 25% palm oil methyl ester by volume, the results indicated an increase in brake thermal efficiency from 29.75% with zero hydrogen flow to a maximum of 30.17% at 5lpm hydrogen flow rate. HC emission reduced from 34 to 31.5 ppm, by volume at maximum load. Whereas, CO emission reduced from 0.09 to 0.045 % by volume at maximum load. Due to higher combustion rates with hydrogen induction, NOx emission increased from 756 to 926 ppm, at maximum load.

Randomized Controlled Trial Examining the Ripple Effect of a Nationally Available Weight Management Program on Untreated Spouses.

Science.gov (United States)

Gorin, Amy A; Lenz, Erin M; Cornelius, Talea; Huedo-Medina, Tania; Wojtanowski, Alexis C; Foster, Gary D

2018-03-01

For married couples, when one spouse participates in weight loss treatment, the untreated spouse can also experience weight loss. This study examined this ripple effect in a nationally available weight management program. One hundred thirty dyads were randomized to Weight Watchers (WW; n = 65) or to a self-guided control group (SG; n = 65) and assessed at 0, 3, and 6 months. Inclusion criteria were age ≥ 25 years, BMI 27 to 40 kg/m 2 (≥ 25 kg/m 2 for untreated spouses), and no weight loss contraindications. WW participants received 6 months of free access to in-person meetings and online tools. SG participants received a weight loss handout. Spouses did not receive treatment. Untreated spouses lost weight at 3 months (WW = -1.5 ± 2.9 kg; SG = -1.1 ± 3.3 kg) and 6 months (WW = -2.2 ± 4.2 kg; SG = -1.9 ± 3.6 kg), but weight losses did not differ by condition. Overall, 32.0% of untreated spouses lost ≥ 3% of initial body weight by 6 months. Baseline weight was significantly correlated within couples (r = 0.26; P ripple effect was found in untreated spouses in both formal and self-guided weight management approaches. These data suggest that weight loss can spread within couples, and that widely available lifestyle programs have weight loss effects beyond the treated individual. © 2018 The Authors. Obesity published by Wiley Periodicals, Inc. on behalf of The Obesity Society (TOS).

Emissions from Petrol Engine Fueled Gasoline–Ethanol–Methanol (GEM Ternary mixture as Alternative Fuel

Directory of Open Access Journals (Sweden)

Thangavelu Saravana Kannan

2015-01-01

Full Text Available The increasing demands of petroleum fuels due to the rapid development automotive society coupled with the environmental pollution issues have inspired the efforts on exploring alternative fuels for internal combustion engines. Bioethanol obtained from biomass and bioenergy crops has been proclaimed as one of the feasible alternative to gasoline. In this study, the effect of gasoline–ethanol–methanol (GEM ternary blend on the emission characteristics of petrol engine was studied. Three different fuel blends, namely, E0 (gasoline, G75E21M4 (75% gasoline, 21% hydrous ethanol and 4% methanol and E25 (25% anhydrous ethanol and 75% gasoline were tested in a 1.3-l K3-VE spark-ignition engine. The results indicate that, when G75E21M4 fuel blend was used, a significant drop in CO, CO2, NOx and HC emissions by about 42%, 15%, 7% and 5.2% compared to E0, respectively. Moreover, the emission results for G75E21M4 are marginally lower than E25 whereas; HC emission was slightly higher than E25.

Effects of dual-energy CT with non-linear blending on abdominal CT angiography

International Nuclear Information System (INIS)

Li, Sulan; Wang, Chaoqin; Jiang, Xiao Chen; Xu, Ge

2014-01-01

To determine whether non-linear blending technique for arterial-phase dual-energy abdominal CT angiography (CTA) could improve image quality compared to the linear blending technique and conventional 120 kVp imaging. This study included 118 patients who had accepted dual-energy abdominal CTA in the arterial phase. They were assigned to Sn140/80 kVp protocol (protocol A, n = 40) if body mass index (BMI) < 25 or Sn140/100 kVp protocol (protocol B, n = 41) if BMI ≥ 25. Non-linear blending images and linear blending images with a weighting factor of 0.5 in each protocol were generated and compared with the conventional 120 kVp images (protocol C, n = 37). The abdominal vascular enhancements, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and radiation dose were assessed. Statistical analysis was performed using one-way analysis of variance test, independent t test, Mann-Whitney U test, and Kruskal-Wallis test. Mean vascular attenuation, CNR, SNR and subjective image quality score for the non-linear blending images in each protocol were all higher compared to the corresponding linear blending images and 120 kVp images (p values ranging from < 0.001 to 0.007) except for when compared to non-linear blending images for protocol B and 120 kVp images in CNR and SNR. No significant differences were found in image noise among the three kinds of images and the same kind of images in different protocols, but the lowest radiation dose was shown in protocol A. Non-linear blending technique of dual-energy CT can improve the image quality of arterial-phase abdominal CTA, especially with the Sn140/80 kVp scanning.

Effects of dual-energy CT with non-linear blending on abdominal CT angiography

Energy Technology Data Exchange (ETDEWEB)

Li, Sulan; Wang, Chaoqin; Jiang, Xiao Chen; Xu, Ge [Dept. of Radiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou (China)

2014-08-15

To determine whether non-linear blending technique for arterial-phase dual-energy abdominal CT angiography (CTA) could improve image quality compared to the linear blending technique and conventional 120 kVp imaging. This study included 118 patients who had accepted dual-energy abdominal CTA in the arterial phase. They were assigned to Sn140/80 kVp protocol (protocol A, n = 40) if body mass index (BMI) < 25 or Sn140/100 kVp protocol (protocol B, n = 41) if BMI ≥ 25. Non-linear blending images and linear blending images with a weighting factor of 0.5 in each protocol were generated and compared with the conventional 120 kVp images (protocol C, n = 37). The abdominal vascular enhancements, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and radiation dose were assessed. Statistical analysis was performed using one-way analysis of variance test, independent t test, Mann-Whitney U test, and Kruskal-Wallis test. Mean vascular attenuation, CNR, SNR and subjective image quality score for the non-linear blending images in each protocol were all higher compared to the corresponding linear blending images and 120 kVp images (p values ranging from < 0.001 to 0.007) except for when compared to non-linear blending images for protocol B and 120 kVp images in CNR and SNR. No significant differences were found in image noise among the three kinds of images and the same kind of images in different protocols, but the lowest radiation dose was shown in protocol A. Non-linear blending technique of dual-energy CT can improve the image quality of arterial-phase abdominal CTA, especially with the Sn140/80 kVp scanning.

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...

Metabolite changes during natural and lactic acid bacteria fermentations in pastes of soybeans and soybean–maize blends

Science.gov (United States)

Ng'ong'ola-Manani, Tinna Austen; Østlie, Hilde Marit; Mwangwela, Agnes Mbachi; Wicklund, Trude

2014-01-01

The effect of natural and lactic acid bacteria (LAB) fermentation processes on metabolite changes in pastes of soybeans and soybean–maize blends was studied. Pastes composed of 100% soybeans, 90% soybeans and 10% maize, and 75% soybeans and 25% maize were naturally fermented (NFP), and were fermented by lactic acid bacteria (LFP). LAB fermentation processes were facilitated through back-slopping using a traditional fermented gruel, thobwa as an inoculum. Naturally fermented pastes were designated 100S, 90S, and 75S, while LFP were designated 100SBS, 90SBS, and 75SBS. All samples, except 75SBS, showed highest increase in soluble protein content at 48 h and this was highest in 100S (49%) followed by 90SBS (15%), while increases in 100SBS, 90S, and 75S were about 12%. Significant (P acids throughout fermentation were attributed to cysteine in 100S and 90S; and methionine in 100S and 90SBS. A 3.2% increase in sum of total amino acids was observed in 75SBS at 72 h, while decreases up to 7.4% in 100SBS at 48 and 72 h, 6.8% in 100S at 48 h and 4.7% in 75S at 72 h were observed. Increases in free amino acids throughout fermentation were observed in glutamate (NFP and 75SBS), GABA and alanine (LFP). Lactic acid was 2.5- to 3.5-fold higher in LFP than in NFP, and other organic acids detected were acetate and succinate. Maltose levels were the highest among the reducing sugars and were two to four times higher in LFP than in NFP at the beginning of the fermentation, but at 72 h, only fructose levels were significantly (P acid solubility and degradation of phytic acid (85% in NFP and 49% in LFP by 72 h). PMID:25493196

Performance and Combustion Characteristics Analysis of Multi-Cylinder CI Engine Using Essential Oil Blends

Directory of Open Access Journals (Sweden)

S. M. Ashrafur Rahman

2018-03-01

Full Text Available Essential oils are derived from not-fatty parts of plants and are mostly used in aromatherapy, as well as cosmetics and perfume production. The essential oils market is growing rapidly due to their claimed health benefits. However, because only therapeutic grade oil is required in the medicinal sector, there is a substantial low-value waste stream of essential oils that can be used in the transportation and agricultural sectors. This study investigated the influence of orange, eucalyptus, and tea tree oil on engine performance and combustion characteristics of a multi-cylinder compression ignition engine. Orange, eucalyptus, and tea tree oil were blended with diesel at 10% by volume. For benchmarking, neat diesel and 10% waste cooking biodiesel-diesel blend were also tested. The selected fuels were used to conduct engine test runs with a constant engine speed (1500 RPM (revolutions per minute at four loads. As the load increased, frictional power losses decreased for all of the fuel samples and thus mechanical efficiency increased. At higher loads (75% and 100%, only orange oil-diesel blends produced comparable power to diesel and waste cooking biodiesel-diesel blends. Fuel consumption (brake and indicated for the essential oil-diesel blends was higher when compared to base diesel and waste cooking biodiesel-diesel blends. Thermal efficiency for the essential oil-diesel blends was comparable to base diesel and waste cooking biodiesel-diesel blends. At higher loads, blow-by was lower for essential oil blends as compared to base diesel and waste cooking biodiesel-diesel blends. At 50% and 100% load, peak pressure was lower for all of the essential oil-diesel blends when compared to base diesel and waste cooking biodiesel-diesel blends. From the heat release rate curve, the essential oil-diesel blends ignition delay times were longer because the oils have lower cetane values. Overall, the low-value streams of these essential oils were found to be

Stress corrosion of the alloy U-7.5 Nb-2.5 Zr

International Nuclear Information System (INIS)

Lepoutre, D.; Nomine, A.M.; Miannay, D.

1983-09-01

Oxide formed on U-7.5 Nb-2.5 Zr at room temperature during stress corrosion cracking in oxygen is identical to the natural oxide of the alloy. It is formed by UO 2 with Nb and Zr and is associated with an increased Nb content at the interface. This oxide would be responsible for cracking [fr

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)

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.

Effects of Biodiesel Blend on Marine Fuel Characteristics for Marine Vessels

Directory of Open Access Journals (Sweden)

Cherng-Yuan Lin

2013-09-01

Full Text Available Biodiesel produced from vegetable oils, animal fats and algae oil is a renewable, environmentally friendly and clean alternative fuel that reduces pollutants and greenhouse gas emissions in marine applications. This study investigates the influence of biodiesel blend on the characteristics of residual and distillate marine fuels. Adequate correlation equations are applied to calculate the fuel properties of the blended marine fuels with biodiesel. Residual marine fuel RMA has inferior fuel characteristics compared with distillate marine fuel DMA and biodiesel. The flash point of marine fuel RMA could be increased by 20% if blended with 20 vol% biodiesel. The sulfur content of residual marine fuel could meet the requirement of the 2008 MARPOL Annex VI Amendment by blending it with 23.0 vol% biodiesel. In addition, the kinematic viscosity of residual marine fuel could be reduced by 12.9% and the carbon residue by 23.6% if 20 vol% and 25 vol% biodiesel are used, respectively. Residual marine fuel blended with 20 vol% biodiesel decreases its lower heating value by 1.9%. Moreover, the fuel properties of residual marine fuel are found to improve more significantly with biodiesel blending than those of distillate marine fuel.

Crystal structure and high-temperature properties of the Ruddlesden–Popper phases Sr3−xYx(Fe1.25Ni0.75)O7−δ (0≤x≤0.75)

International Nuclear Information System (INIS)

Samain, Louise; Amshoff, Philipp; Biendicho, Jordi J.; Tietz, Frank; Mahmoud, Abdelfattah; Hermann, Raphaël P.; Istomin, Sergey Ya.; Grins, Jekabs; Svensson, Gunnar

2015-01-01

Ruddlesden–Popper n=2 member phases Sr 3−x Y x Fe 1.25 Ni 0.75 O 7−δ , 0≤x≤0.75, have been investigated by X-ray and neutron powder diffraction, thermogravimetry and Mössbauer spectroscopy. Both samples as-prepared at 1300 °C under N 2 (g) flow and samples subsequently air-annealed at 900 °C were studied. The as-prepared x=0.75 phase is highly oxygen deficient with δ=1, the O1 atom site being vacant, and the Fe 3+ /Ni 2+ ions having a square pyramidal coordination. For as-prepared phases with lower x values, the Mössbauer spectral data are in good agreement with the presence of both 5- and 4-coordinated Fe 3+ ions, implying in addition a partial occupancy of the O3 atom sites that form the basal plane of the square pyramid. The air-annealed x=0.75 sample has a δ value of 0.61(1) and the structure has Fe/Ni ions in both square pyramids and octahedra. Mössbauer spectroscopy shows the phase to contain only Fe 3+ , implying that all Ni is present as Ni 3+ . Air-annealed phases with lower x values are found to contain both Fe 3+ and Fe 4+ . For both the as-prepared and the air-annealed samples, the Y 3+ cations are found to be mainly located in the perovskite block. The high-temperature thermal expansion of as-prepared and air-annealed x=0.75 phases were investigated by high-temperature X-ray diffraction and dilatometry and the linear thermal expansion coefficient determined to be 14.4 ppm K −1 . Electrical conductivity measurements showed that the air-annealed samples have higher conductivity than the as-prepared ones. - Highlights: • Ruddlesden–Popper, n=2, Sr 3−x Y x Fe 1.25 Ni 0.75 O 7−δ , 0≤x≤0.75, have been synthesised. • The crystal structures of the phases have been determined. • Sr 2.25 Y 0.75 Fe 1.25 Ni 0.75 O 6 , made in N 2 (g) has Fe 3+ /Ni 2+ in square pyramides. • Sr 2.25 Y 0.75 Fe 1.25 Ni 0.75 O 6.4 , made in air has Fe 3+ /Ni 3+ in square pyramides and octahedra. • Air annealed samples have higher electrical

Synergistic effects and kinetics thermal behaviour of petroleum coke/biomass blends during H2O co-gasification

International Nuclear Information System (INIS)

Edreis, Elbager M.A.; Luo, Guangqian; Li, Aijun; Xu, Chaofen; Yao, Hong

2014-01-01

Highlights: • Sugar cane bagasse and blends gasification presented two stages at all H 2 O values. • Petroleum coke showed only one char gasification stage at (>700 °C) at 75% H 2 O. • Significant interactions are existed in the both reaction stages of samples. • Higher H 2 O concentration and PC content lead to higher kinetic parameter values. • All the models are successfully utilized to predict the experimental data. - Abstract: This study investigates the possible synergistic interactions between the Sudanese lower sulphur petroleum coke (PC) and sugar cane bagasse (SCB) during H 2 O co-gasification with three concentration values (25%, 50% and 75% v/v) using a thermogravimetric analyser (TGA) at 20 °C/min. The kinetic thermal behaviour, and effects of both H 2 O concentration and fuel blending ratio were investigated. The results show that, significant interactions existed in both reaction stages of samples, and become less when PC content and H 2 O concentration are 50%. Petroleum coke showed only one char gasification stage at (>700 °C) at 75% H 2 O. Some kinetics models like homogeneous and shrinking core models were studied by the Coats–Redfern method in order to observe the optimum reaction mechanism for the H 2 O gasification of samples, describe the best reactive behaviour and determine the kinetic parameters. The results showed that, the co-gasification behaviour and kinetic parameters have a significantly influenced by increasing both H 2 O concentration and PC content. The boundary controlled reaction model (R2) shows the lowest values of activation energy (E) for all samples and H 2 O concentrations. Finally, all the models are successfully utilized to predict the experimental data under all H 2 O concentration values

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

Utilization of fermented animal by-product blend as fishmeal replacer in the diet of Labeo rohita

Directory of Open Access Journals (Sweden)

Ayan Samaddar

2015-05-01

Full Text Available Experiments were carried out to evaluate efficiency of Labeo rohita to utilize fermented animal protein blend containing slaughter house blood (SHB and fish offal (FO as dietary fishmeal (FM replacer. Five isoproteic (30%, isolipidic (8% and isoenergitic (15.00 kJ g−1 feed were prepared by replacing 0 (T1, 25 (T2, 50 (T3, 75 (T4 and 100% (T5 FM protein with the fermented blend and fingerlings of L. rohita (mean weight 2.07 g were fed each of these feed in triplicate groups. The results showed that apparent digestibility coefficient (ADC of protein significantly increased in T3–T5, while ADC of lipid and total amino acid absorption rate increased in T2–T5 as compared to control (T1. Among the essential amino acids (EAA, arginine exhibited maximum absorption followed by histidine, phenylalanine, valine and lysine while aspartic acid showed a high absorption among the non-essential amino acids (NAA. Fish fed up to 75% of replacement level (T4 did not show any significant difference (P < 0.05 in weight gain (WG, specific growth rate (SGR, feed conversion ratio (FCR, protein efficiency ratio (PER and apparent net protein utilization (ANPU between the dietary groups (T1–T4. But FCR was increased and other growth parameters were significantly reduced in 100% replacement group (T5, while body muscle protein was significantly reduced in both T4 and T5. Deposition of EAA (except histidine and methionine in T4 and NAA (except cystine in both T4 and T5 in the muscle of fish were also significantly reduced as compared to control (T1. Multi-objective optimization programming technique was used to determine FM replacement level that optimized all the growth parameters (WG, SGR, FCR and PER simultaneously. By using Global Criterion method, it was obtained that 21.11% replacement of FM by the fermented blend was ideal for optimum growth of L. rohita.

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)

Instant blend from cassava derivatives produced by extrusion

OpenAIRE

Trombini, Fernanda Rossi Moretti; Mischan, Martha Maria; Leonel, Magali

2016-01-01

ABSTRACT: The current research aimed to evaluate the effects of extrusion parameters on the physical characteristics of extruded blends of cassava leaf flour and starch. A factorial central composite design with four independent variables and the response surface methodology were used to evaluate the results of color parameters (L*, a*, b*), water absorption index, water solubility index and paste properties, according to the variations in the leaf flour percentage (1.5 to 7.5%), extrusion te...

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).

Novel biocompatible polymeric blends for bone regeneration: Material and matrix design and development

Science.gov (United States)

Deng, Meng

The first part of the work presented in this dissertation is focused on the design and development of novel miscible and biocompatible polyphosphazene-polyester blends as candidate materials for scaffold-based bone tissue engineering applications. Biodegradable polyesters such as poly(lactide-co-glycolide) (PLAGA) are among the most widely used polymeric materials for bone tissue engineering. However, acidic degradation products resulting from the bulk degradation mechanism often lead to catastrophic failure of the structure integrity, and adversely affect biocompatibility both in vitro and in vivo. One promising approach to circumvent these limitations is to blend PLAGA with other macromolecules that can buffer the acidic degradation products with a controlled degradation rate. Biodegradable polyphosphazenes (PPHOS), a new class of biomedical materials, have proved to be superior candidate materials to achieve this objective due to their unique buffering degradation products. A highly practical blending approach was adopted to develop novel biocompatible, miscible blends of these two polymers. In order to achieve this miscibility, a series of amino acid ester, alkoxy, aryloxy, and dipeptide substituted PPHOS were synthesized to promote hydrogen bonding interactions with PLAGA. Five mixed-substituent PPHOS compositions were designed and blended with PLAGA at different weight ratios producing candidate blends via a mutual solvent method. Preliminary characterization identified two specific side groups namely glycylglycine dipeptide and phenylphenoxy that resulted in improved blend miscibility and enhanced in vitro osteocompatibility. These findings led to the synthesis of a mixed-substituent polyphosphazene poly[(glycine ethyl glycinato)1(phenylphenoxy)1phosphazene] (PNGEGPhPh) for blending with PLAGA. Two dipeptide-based blends having weight ratios of PNGEGPhPh to PLAGA namely 25:75 (Matrix1) and 50:50 (Matrix2) were fabricated. Both of the blends were

Electrospun nanofibrous SF/P(LLA-CL) membrane: a potential substratum for endothelial keratoplasty.

Science.gov (United States)

Chen, Junzhao; Yan, Chenxi; Zhu, Mengyu; Yao, Qinke; Shao, Chunyi; Lu, Wenjuan; Wang, Jing; Mo, Xiumei; Gu, Ping; Fu, Yao; Fan, Xianqun

2015-01-01

Cornea transplant technology has progressed markedly in recent decades, allowing surgeons to replace diseased corneal endothelium by a thin lamellar structure. A thin, transparent, biocompatible, tissue-engineered substratum with corneal endothelial cells for endothelial keratoplasty is currently of interest. Electrospinning a nanofibrous structure can simulate the extracellular matrix and have beneficial effects for cell culture. Silk fibroin (SF) has good biocompatibility but poor mechanical properties, while poly(L-lactic acid-co-ε-caprolactone) (P(LLA-CL)) has good mechanical properties but poor biocompatibility. Blending SF with P(LLA-CL) can maintain the advantages of both these materials and overcome their disadvantages. Blended electrospun nanofibrous membranes may be suitable for regeneration of the corneal endothelium. The aim of this study was to produce a tissue-engineered construct suitable for endothelial keratoplasty. Five scaffolds containing different SF:P(LLA-CL) blended ratios (100:0, 75:25, 50:50, 25:75, 0:100) were manufactured. A human corneal endothelial (B4G12) cell line was cultured on the membranes. Light transmission, speed of cell adherence, cell viability (live-dead test), cell proliferation (Ki-67, BrdU staining), and cell monolayer formation were detected on membranes with the different blended ratios, and expression of some functional genes was also detected by real-time polymerase chain reaction. Different blended ratios of scaffolds had different light transmittance properties. The 25:75 blended ratio membrane had the best transmittance among these scaffolds. All electrospun nanofibrous membranes showed improved speed of cell adherence when compared with the control group, especially when the P(LLA-CL) ratio increased. The 25:75 blended ratio membranes also had the highest cell proliferation. B4G12 cells could form a monolayer on all scaffolds, and most functional genes were also stably expressed on all scaffolds. Only two genes

Preparation of alanine/ESR dosimeter using different binder of polymer blend

International Nuclear Information System (INIS)

Razzak, M.T.; Sudiro, Sutjipto; Sudradjat, Adjat; Waskito, Ashar; Djamili, M.F.

1995-01-01

Different composition of polymer blend of low density polyethylene (PE) and polystyrene (PS) have been studied to be used as a binder for the preparation of Alanine/ESR dosimeter. The polymer binder and Alanine powder were blended in Laboplastomil Mixer at 140 o C and then it was pressed into a plastic film of 0.50 mm thickness. The film was cut into sample size of 250 mm x 2.5 mm and irradiated by gamma rays from a cobalt-60 source at different dose and dose rate. It was found that a blend of Alanine, PS and PE in composition of 60:30:10 is appropriate to prepare the Alanine/ESR dosimeter. (author)

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.

The Molecular Structures of the Local Arm and Perseus Arm in the Galactic Region of l  = [139.°75, 149.°75], b  = [−5.°25, 5.°25

Energy Technology Data Exchange (ETDEWEB)

Du, Xinyu; Xu, Ye; Yang, Ji; Sun, Yan, E-mail: xydu@pmo.ac.cn, E-mail: xuye@pmo.ac.cn [Purple Mountain Observatory, Chinese Academy of Science, Nanjing 210008 (China)

2017-04-01

Using the Purple Mountain Observatory Delingha (PMODLH) 13.7 m telescope, we report a 96 deg{sup 2} {sup 12}CO/{sup 13}CO/C{sup 18}O mapping observation toward the Galactic region of l  = [139.°75,149.°75], b  = [−5.°25, 5.°25]. The molecular structures of the Local Arm and Perseus Arm are presented. Combining H i data and part of the Outer Arm results, we obtain that the warp structure of both atomic and molecular gas is obvious, while the flare structure only exists in atomic gas in this observing region. In addition, five filamentary giant molecular clouds on the Perseus Arm are identified. Among them, four are newly identified. Their relations with the Milky Way large-scale structure are discussed.

The use of biodiesel blends on a non-road generator and its impacts on ozone formation potentials based on carbonyl emissions

International Nuclear Information System (INIS)

Chai, Ming; Lu, Mingming; Liang, Fuyan; Tzillah, Aisha; Dendramis, Nancy; Watson, Libya

2013-01-01

In this study, emissions of carbonyl compounds from the use B50 and B100 were measured with a non-road diesel generator. A total of 25 carbonyl compounds were identified in the exhaust, including 10 with laboratory-synthesized standards. Formaldehyde, acetaldehyde, and acrolein were found as the most abundant carbonyl compounds emitted for both diesel and biodiesel. The sulphur content of diesel fuels and the source of biodiesel fuels were not found to have a significant impact on the emission of carbonyl compounds. The overall maximum incremental reactivity (MIR) was the highest at 0 kW and slightly increased from 25 to 75 kW. The MIR of B100 was the highest, followed by diesel and B50, which is consistent with the emission rates of total carbonyl compounds. This suggests that the use of biodiesel blends may be more beneficial to the environment than using pure biodiesel. -- Highlights: •Carbonyl compound emission from biodiesel blends combustion on a non-road generator. •25 compounds were identified, including 10 by laboratory-synthesized standards. •Sources of biodiesel have insignificant impacts on carbonyl compounds emission. •Sulphur contents have insignificant impacts on carbonyl compounds emission. •MIR of emitted carbonyls decreases in the following order: B100, diesel, B50. -- The study found that B50 resulted in lower total carbonyl emission rates and ozone formation potential resultant from these compounds, whereas both increased with B100

Progression of Treated versus Untreated Liver Imaging Reporting and Data System Category 4 Masses after Transcatheter Arterial Embolization Therapy.

Science.gov (United States)

Ronald, James; Gupta, Rajan T; Marin, Daniele; Wang, Qi; Durocher, Nicholas S; Suhocki, Paul V; Kim, Charles Y

2018-05-01

To compare outcomes of treated vs untreated Liver Imaging Reporting and Data System category 4 (LR-4) masses after transcatheter arterial embolization. In 167 patients undergoing embolization for HCC from January 2005 to December 2012, LR-4 masses were retrospectively identified on CT and MR imaging examinations performed before embolization. In 149 patients undergoing embolization from January 2013 to December 2016, masses prospectively classified as LR-4 were identified. In total, there were 81 LR-4 masses in 62 patients (16 women; mean age 62 y; range 29-83 y). Procedures were reviewed to determine whether LR-4 masses were within or outside the liver volume that received embolization during treatment of dominant masses. Time to progression to LR-5 and by modified Response Evaluation Criteria in Solid Tumors (mRECIST) was estimated for treated vs untreated LR-4 masses using the Kaplan-Meier method and compared using the log rank test. LR-4 masses averaged 1.8 cm; 88%, 60%, 14%, and 14% demonstrated arterial phase hyperenhancement, washout, a capsule, and growth. Of LR-4 masses, 62 were within the liver volume that received embolization and considered treated, and 19 were outside and considered untreated. Response rates according to mRECIST were 37% vs 21% for treated vs untreated masses (P = .27). The 6- and 12-month rates of progression to LR-5 were 7% and 26% for treated masses vs 27% and 75% for untreated masses (P = .001). According to mRECIST, 7% and 27% of treated masses progressed vs 30% and 65% of untreated masses (P = .001). LR-4 masses that receive embolization in the setting of dominant masses elsewhere show lower rates of progression compared with untreated masses. Copyright © 2017 SIR. Published by Elsevier Inc. All rights reserved.

Oxygen adsorption on the Al0.25Ga0.75N (0001) surface: A first-principles study

Science.gov (United States)

Fu, Jiaqi; Song, Tielei; Liang, Xixia; Zhao, Guojun

2018-04-01

To understand the interaction mechanism for the oxygen adsorption on AlGaN surface, herein, we built the possible models of oxygen adsorption on Al0.25Ga0.75N (0001) surface. For different oxygen coverage, three kinds of adsorption site are considered. Then the favorable adsorption sites are characterized by first principles calculation for (2 × 2) supercell of Al0.25Ga0.75N (0001) surface. On basis of the optimal adsorption structures, our calculated results show that all the adsorption processes are exothermic, indicating that the (0001) surface orientation is active towards the adsorption of oxygen. The doping of Al is advantage to the adsorption of O atom. Additionally, the adsorption energy decreases with reducing the oxygen coverage, and the relationship between them is approximately linear. Owing to the oxygen adsorption, the surface states in the fundamental band gap are significant reduced with respect to the free Al0.25Ga0.75N (0001) surface. Moreover, the optical properties on different oxygen coverage are also discussed.

Preparation and Effect of Gamma Radiation on The Properties and Biodegradability of Poly(Styrene/Starch) Blends

Science.gov (United States)

Ali, H. E.; Abdel Ghaffar, A. M.

2017-01-01

Biodegradable blends based on Poly(styrene/starch) Poly(Sty/Starch) were prepared by the casting method using different contents of starch in the range of 0-20 wt% aiming at preparing disposable packaging materials. The prepared bio-blends were Characterized by Fourier transform infrared (FTIR), swelling behavior, mechanical properties, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). It was found that the swelling behavior slightly increased with increasing starch content and not exceeding 7.5%. The results showed that by increasing irradiation dose up to 5 kGy, the mechanical properties of the prepared PSty/10 wt% Starch blend film modified than other blend films, and hence it is selected. Also the water resistant increased, by irradiation of the selected PSty/10 wt% Starch blend film. The intermolecular hydrogen bonding interaction between Starch and PSty of the PSty/10 wt% Starch blend film promote a more homogenous blend film as shown in scanning electron microscopy (SEM). The prepared Poly(Sty/Starch) blends with different compositions and the selected irradiated PSty/10 wt% Starch blend were subjected to biodegradation in soil burial tests for 6 months using two different types of soils; agricultural and desert soils, then analyzed gravimetrically and by scanning electron microscopy (SEM). The results suggested that there is a possibility of using irradiated PSty/10 wt% Starch at a dose of 5 kGy as a potential candidate for packaging material.

Magnetic refrigeration capabilities of magnetocaloric Ni2Mn:75Cu:25Ga

Science.gov (United States)

Mishra, S. K.; Jenkins, C. A.; Dubenko, I.; Samanta, T.; Ali, N.; Roy, S.

2013-03-01

Doping-driven competition between energetically similar ground states leads to many exciting materials phenomena such as the emergence of high-Tc superconductivity, diluted magnetic semiconductors, and colossal magnetoresistance. Doped Ni2MnGa Heusler alloy, which is a multifunctional ferromagnetic alloy with various exotic physical properties demonstrates this notion of rich phenomenology via modified ground spin states. Adopting this generic concept, here we will present a novel doped Ni2Mn.75Cu.25Ga alloy that offers unprecedented co-existence of the magnetocaloric effect and fully controlled ferromagnetism at room temperature. Application of site engineering enables us to manipulate the ground spin state that leads to the decrease in magnetic transition temperature and also increases the delocalization of the Mn magnetism. SQUID magnetometery suggests that Cu doping enhances the saturation magnetization, coercive field and clarity of magnetic hysteresis loops. By exploiting x-ray absorption techniques and measuring element specific magnetic hysteresis loops, here we will describe the microscopic origin of enhnaced magnetocaloric properties and d-d interaction driven charge transfer effects in Ni2Mn.75Cu.25Ga This work was supported by DOE Grant No. DE-FG02-06ER46291

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....

Nonlinear Stress Relaxation of ``Quasi-monodisperse'' Miscible Blends of cis-Polyisoprene and Poly(ptert-butylstyrene)

Science.gov (United States)

Watanabe, Hiroshi; Matsumiya, Yumi

Viscoelastic relaxation was examined for entangled miscible blends of cis-polyisoprene (PI) and poly(ptert-butylstyrene) (PtBS). The terminal relaxation times of PI and PtBS therein, τPI and τPtBS, changed with the composition wPI and the molecular weights MPI and MPtBS. This ratio became unity when the wPI, MPI, and MPtBS values were chosen adequately. For example, in a blend with wPI = 0.75, MPI = 321k, and MPtBS = 91k at T = 40ûC, τPI/τPtBS = 1 and M/Me = 55 and 8.3 for PI and PtBS. Under small strains, this blend exhibited sharp, single-step terminal relaxation as similar to monodisperse homopolymers, thereby behaving as a ``quasi-monodisperse'' material. Under large step strains, the blend exhibited moderate nonlinear damping known as the type-A damping for entangled monodisperse homopolymers. Nevertheless, PI had M/Me = 55 in that blend, and homopolymers having such a large M/Me ratio exhibit very strong type-C damping. Thus, as compared to homopolymers, the nonlinearity was suppressed in the PI/PtBS blend having the large M/Me ratio. This suppression is discussed in relation to the slow Rouse retraction of the coexisting PtBS chains (having M/Me = 8.3 in the blend).

Blended learning is an effective strategy for acquiring competence in public health biostatistics.

Science.gov (United States)

Milic, Natasa; Masic, Srdjan; Bjegovic-Mikanovic, Vesna; Trajkovic, Goran; Marinkovic, Jelena; Milin-Lazovic, Jelena; Bukumiric, Zoran; Savic, Marko; Cirkovic, Andja; Gajic, Milan; Stanisavljevic, Dejana

2018-04-01

We sought to determine whether blended learning is an effective strategy for acquiring competence in public health biostatistics. The trial was conducted with 69 Masters' students of public health attending the School of Public Health at University of Belgrade. Students were exposed to the traditional and blended learning styles. Blended learning included a combination of face-to-face and distance learning methodologies integrated into a single course. Curriculum development was guided by competencies as suggested by the Association of Schools of Public Health in the European Region (ASPHER). Teaching methods were compared according to the final competence score. Forty-four students were enrolled in the traditional method of education delivery, and 25 to the blended learning format. Mean exam scores for the blended learning group were higher than for the on-site group for both the final statistics score (89.65 ± 6.93 vs. 78.21 ± 13.26; p  0.8). A blended learning approach is an attractive and effective way of acquiring biostatistics competence for Masters of Public Health (MPH) graduate students.

Acceptability of Noodles Produced from Blends of Wheat, Acha and ...

African Journals Online (AJOL)

Acha (Digitaria exilis) and soybean (Glycine max) were processed into flours and used to substitute wheat flour (Titicum aestivm) as a composite flour at different proportions of 100:0:0 (Wheat); 75:25:25 (Wheat: Acha: Soybean); 75:25 (Wheat: Acha); 75:25 (Wheat: Soybean) and 50:50 (Acha: soybean). The formulated ...

The Improvement of Screening the Significant Factors of Oil Blends as Bio lubricant Base Stock

International Nuclear Information System (INIS)

Noor Hajarul Ashikin Shamsuddin; Rozaini Abdullah; Zainab Hamzah; Siti Jamilah Hanim Mohd Yusof

2015-01-01

A new formulation bio lubricant base stock was developed by blending of waste cooking oil (WCO) with Jatropha curcas oil (JCO). The objective of this research is to evaluate significant factors contributing to the production of oil blends for bio lubricant application. The significant factors used in this study were oil ratio (WCO:JCO), agitation times (min) and agitation speed (rpm). The blended oil bio based lubricant was used to determine the saponification, acid, peroxide and iodine values. The experimental design used in this study was the 2 level-factorial design. In this experiment, it was found that the effect of oil ratio and interaction of oil ratio and agitation speed gave the most significant effect in oil blends as bio lubricant base stock. The highest ratio of oil blend 80 %:20 % WCO:JCO, with low agitation speed of 300 rpm and low agitation time of 30 minutes gave the optimum results. The acid, saponification, peroxide and iodine values obtained were 0.517±0.08 mg KOH/ g, 126.23±1.62 mg/ g, 7.5±2.0 m eq/ kg and 50.42±2.85 mg/ g respectively. A higher ratio of waste cooking oil blends was found to be favourable as bio lubricant base stock. (author)

Estudo comparativo entre bupivacaína racêmica a 0,25% e bupivacaína com excesso enantiomérico de 50% (S75-R25 a 0,25%, associadas ao fentanil para analgesia de parto com deambulação da parturiente Estudio comparativo entre bupivacaína racémica a 0,25% y bupivacaína con exceso enantiomérico de 50% (S75-R25 a 0,25% asociadas con fentanil para analgesia de parto con deambulación de la gestante Racemic 0.25% bupivacaine and 50% enantiomeric excess (S75-R25 0.25% bupivacaine associated to fentanyl for labor analgesia with patient’s ambulation. Comparative study

Directory of Open Access Journals (Sweden)

Carlos Alberto Figueiredo Côrtes

2006-02-01

Full Text Available JUSTIFICATIVA E OBJETIVOS: Estudos clínicos com enantiômeros levógiros dos anestésicos locais demonstraram maior segurança em função de menor cardiotoxicidade. A deambulação da parturiente durante o trabalho de parto pode abreviar o trabalho de parto. Este estudo visou comparar a qualidade da anestesia e as repercussões maternas e fetais bem como a capacidade de deambulação e micção espontânea das parturientes com o emprego da bupivacaína a 0,25% e da bupivacaína com excesso enantiomérico de 50% (S75-R25 a 0,25%, associadas ao fentanil por via peridural contínua, no trabalho de parto. MÉTODO: Foram avaliadas 40 parturientes, estado físico ASA I e II, feto único, em trabalho de parto, submetidas a analgesia peridural contínua e divididas em dois grupos: no grupo I, receberam 8 mL (20 mg de bupivacaína (S75-R25 a 0,25% com epinefrina, associados a 100 µg de fentanil. No grupo II, receberam 8 mL (20 mg de bupivacaína racêmica a 0,25% com epinefrina, associados a 100 µg de fentanil. Foram avaliados os seguintes parâmetros: tempo de latência, nível de bloqueio sensitivo, grau de bloqueio motor, teste de Romberg, capacidade de deambulação e micção espontânea, duração do trabalho de parto e do período expulsivo, alterações hemodinâmicas e respiratórias maternas além da vitalidade dos recém-nascidos. RESULTADOS: Não houve diferença estatística significativa entre os grupos nos parâmetros avaliados. Todas as parturientes apresentaram força muscular com capacidade de deambulação, salvo no caso de indicação de cesariana (um caso do grupo II ou quando o parto aconteceu antes do tempo previsto para avaliação deste parâmetro (quatro casos do grupo I e cinco casos do grupo II. CONCLUSÕES: Tanto a bupivacaína racêmica quanto a bupivacaína (S75-R25 a 0,25% associadas ao fentanil mostraram ser boa opção para analgesia de parto.JUSTIFICATIVA Y OBJETIVOS: Estudios clínicos con enantiómeros lev

Influence of Zr substitution on the stabilization of ThMn{sub 12}-type (Nd{sub 1−α}Zr{sub α})(Fe{sub 0.75}Co{sub 0.25}){sub 11.25}Ti{sub 0.75}N{sub 1.2−1.4} (α = 0–0.3) compounds

Energy Technology Data Exchange (ETDEWEB)

Sakuma, N.; Yano, M.; Kato, A. [Toyota Motor Corporation, 1200 Mishuku, Susono, Shizuoka 410-1193 (Japan); Technology Research Association of Magnetic Materials for High-Efficiency Motors (MagHEM) Higashifuji-Branch, 1200 Mishuku, Susono, Shizuoka 410-1193 (Japan); Suzuki, S.; Kuno, T.; Urushibata, K.; Kobayashi, K. [Shizuoka Institute of Science and Technology, 2200-2 Toyosawa, Fukuroi, Shizuoka 437-8555 (Japan); Manabe, A. [Technology Research Association of Magnetic Materials for High-Efficiency Motors (MagHEM) Higashifuji-Branch, 1200 Mishuku, Susono, Shizuoka 410-1193 (Japan)

2016-05-15

The influence of Zr substitution in ThMn{sub 12} compounds was investigated using strip casting alloys. It was found that Zr substitution stabilized (Nd{sub 1−α}Zr{sub α})(Fe{sub 0.75}Co{sub 0.25}){sub 11.25}Ti{sub 0.75}N{sub 1.2−1.4} (α = 0–0.3) compounds. Specifically, a reduction in the lattice constant along the a-axis was observed. Energy-dispersive X-ray spectroscopy mapping combined with Cs-corrected scanning transmission electron microscopy indicated that Zr atoms preferentially occupied Nd 2a sites. Both the magnetic anisotropy field and saturation polarization were maximum at Zr substitution ratio α = 0.1. The (Nd{sub 1−α}Zr{sub α})(Fe{sub 0.75}Co{sub 0.25}){sub 11.25}Ti{sub 0.75}N{sub 1.2−1.4} (α = 0–0.3) compounds displayed higher saturation polarization than Nd{sub 2}Fe{sub 14}B at high temperatures.

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)

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...

Laboratory Oxidation Stability Study on B10 Biodiesel Blends

Energy Technology Data Exchange (ETDEWEB)

Engelen, B. [and others

2013-11-15

A laboratory oxidation stability study has been completed jointly by CONCAWE and DGMK on three biodiesel blends containing 10% v/v (B10) Fatty Acid Methyl Ester (FAME). The results of the study are compared to measurements from an in-vehicle storage stability study on similar B10 diesel fuels that had been conducted previously in a Joint Industry Study. This laboratory study monitored the oxidation stability of the three B10 blends during six weeks of laboratory storage under ambient (25C) and elevated temperature (43C) conditions. Various test methods were used to monitor oxidation stability changes in the B10 diesel fuel blends including electrical conductivity, viscosity, Rancimat oxidation stability (EN 15751), PetroOxy oxidation stability (EN 16091), acid number (EN 14104), Delta Total Acid Number (Delta TAN), and peroxide number (ISO 3960). Elemental analyses by ICP were also completed on the FAME and B10 blends at the start and end of the laboratory study. The concentrations of dissolved metals were very low in all cases except for silicon which was found to be between about 600-700 ppb in the B10 blends. A limited study was also conducted on one neat FAME sample (B100) to investigate the effect of air/oxygen exposure on the rate of decrease in oxidation stability.

First-principles calculations of a half-metallic ferromagnet zinc blende Zn{sub 1−x}V{sub x}Te

Energy Technology Data Exchange (ETDEWEB)

El Amine Monir, M.; Baltache, H. [Laboratoire de Physique Quantique de la Modélisation Mathématique (LPQ3M), Université de Mascara, 29000 (Algeria); Khenata, R., E-mail: khenata_rabah@yahoo.fr [Laboratoire de Physique Quantique de la Modélisation Mathématique (LPQ3M), Université de Mascara, 29000 (Algeria); Murtaza, G. [Materials Modeling Laboratory, Department of Physics, Islamia College University, Peshawar (Pakistan); Azam, Sikander [New Technologies-Research Center, University of West Bohemia, Univerzitni 8, 306 14 Pilsen (Czech Republic); Bouhemadou, A. [Laboratory for Developing New Materials and their Characterization, Department of Physics, Faculty of Science, University Setif 1, 19000 Setif (Algeria); Al-Douri, Y. [Institute of Nano Electronic Engineering, University Malaysia Perlis, 01000 Kangar, Perlis (Malaysia); Bin Omran, S. [Department of Physics and Astronomy, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Ali, Roshan [Materials Modeling Lab, Department of Physics, Post Graduate Jahanzeb College, Swat (Pakistan)

2015-03-15

First-principles calculations have been used to study the structural, elastic, electronic, magnetic and thermal properties of zinc blende Zn{sub 1−x}V{sub x}Te for x=0, 0.25, 0.50, 0.75 and 1 using the full-potential linearized augmented plane wave method (FP-LAPW) based on spin-polarized density functional theory (DFT). The electronic exchange-correlation potential is approached using the spin generalized gradient approximation (spin-GGA). The structural properties of the Zn{sub 1−x}V{sub x}Te alloys (x=0, 0.25, 0.50, 0.75 and 1) are given for the lattice constants and the bulk moduli and their pressure derivatives. The elastic constants C{sub 11}, C{sub 12} and C{sub 44} are calculated using numerical first-principles calculations implemented in the WIEN2k package. An analysis of the band structures and the densities of states reveals that Zn{sub 0.50}V{sub 0.50}Te and Zn{sub 0.75}V{sub 0.25}Te exhibit a half-metallic character, while Zn{sub 0.25}V{sub 0.75}Te is nearly half-metallic. The band structure calculations are used to estimate the spin-polarized splitting energies Δ{sub x}(d) and Δ{sub x}(pd) produced by the V(3d)-doped and s(p)–d exchange constants N{sub 0α} (conduction band) and N{sub 0β} (valence band). The p–d hybridization reduces the magnetic moment of V from its atomic charge value of 3µ{sub B} and creates small local magnetic moments on the nonmagnetic Zn and Te sites. Finally, we present the thermal effect on the macroscopic properties of these alloys, such as the thermal expansion coefficient, heat capacity and Debye temperature, based on the quasi-harmonic Debye model. - Highlights: • Some physical properties of Vanadium doped ZnTe have been investigated. • Structural parameters for the parent compounds compare well with the available data. • The elastic and thermal properties are studied for the first time.

Frequency Selective Non-Linear Blending to Improve Image Quality in Liver CT.

Science.gov (United States)

Bongers, M N; Bier, G; Kloth, C; Schabel, C; Fritz, J; Nikolaou, K; Horger, M

2016-12-01

Purpose: To evaluate the effects of a new frequency selective non-linear blending (NLB) algorithm on the contrast resolution of liver CT with low intravascular concentration of iodine contrast. Materials and Methods: Our local ethics committee approved this retrospective study. The informed consent requirement was waived. CT exams of 25 patients (60 % female, mean age: 65 ± 16 years of age) with late phase CT scans of the liver were included as a model for poor intrahepatic vascular contrast enhancement. Optimal post-processing settings to enhance the contrast of hepatic vessels were determined. Outcome variables included signal-to-noise (SNR) and contrast-to-noise ratios (CNR) of hepatic vessels and SNR of liver parenchyma of standard and post-processed images. Image quality was quantified by two independent readers using Likert scales. Results: The post-processing settings for the visualization of hepatic vasculature were optimal at a center of 115HU, delta of 25HU, and slope of 5. Image noise was statistically indifferent between standard and post-processed images. The CNR between the hepatic vasculature (HV) and liver parenchyma could be significantly increased for liver veins (CNR Standard 1.62 ± 1.10, CNR NLB 3.6 ± 2.94, p = 0.0002) and portal veins (CNR Standard 1.31 ± 0.85, CNR NLB 2.42 ± 3.03, p = 0.046). The SNR of liver parenchyma was significantly higher on post-processed images (SNR NLB 11.26 ± 3.16, SNR Standard 8.85 ± 2.27, p = 0.008). The overall image quality and depiction of HV were significantly higher on post-processed images (NLB DHV : 4 [3 - 4.75], S tandardDHV : 2 [1.3 - 2.5], p = algorithm increases the contrast resolution of liver CT and can improve the visibility of the hepatic vasculature in the setting of a low contrast ratio between vessels and the parenchyma. Key Points: • Using the new frequency selective non-linear blending algorithm is feasible in contrast

System simulation for an untreated sewage source heat pump (USSHP) in winter

Science.gov (United States)

Qin, Na; Hao, Peng Z.

2017-01-01

The paper discusses the system characteristics of an untreated sewage source heat pump in winter. In this system, the sewage enters into the evaporator directly. The variable parameters to control the system contain the sewage temperature at evaporator inlet and the water temperature at condenser inlet. It is found that most parameters, except the condensation heat transfer coefficient, change in the form of sine wave the same as the sewage temperature at inlet. The heating load and consumed power are 12.9kW and 3.45kW when the sewage temperature at inlet is 13°C. COP is about 3.75 in the range of the sewage temperature at inlet of 12-13°C.

Assessment of Blend PVDF Membranes, and the Effect of Polymer Concentration and Blend Composition

Directory of Open Access Journals (Sweden)

Imtiaz Ali

2018-03-01

Full Text Available In this work, PVDF homopolymer was blended with PVDF-co-HFP copolymer and studied in terms of morphology, porosity, pore size, hydrophobicity, permeability, and mechanical properties. Different solvents, namely N-Methyl-2 pyrrolidone (NMP, Tetrahydrofuran (THF, and Dimethylformamide (DMF solvents, were used to fabricate blended PVDF flat sheet membranes without the introduction of any pore forming agent, through a non-solvent induced phase separation (NIPS technique. Furthermore, the performance of the fabricated membranes was investigated for pressure and thermal driven applications. The porosity of the membranes was slightly increased with the increase in the overall content of PVDF and by the inclusion of PVDF copolymer. Total PVDF content, copolymer content, and mixed-solvent have a positive effect on mechanical properties. The addition of copolymer increased the hydrophobicity when the total PVDF content was 20%. At 25% and with the inclusion of mixed-solvent, the hydrophobicity was adversely affected. The permeability of the membranes increased with the increase in the overall content of PVDF. Mixed-solvents significantly improved permeability.

Assessment of Blend PVDF Membranes, and the Effect of Polymer Concentration and Blend Composition.

Science.gov (United States)

Ali, Imtiaz; Bamaga, Omar A; Gzara, Lassaad; Bassyouni, M; Abdel-Aziz, M H; Soliman, M F; Drioli, Enrico; Albeirutty, Mohammed

2018-03-05

In this work, PVDF homopolymer was blended with PVDF-co-HFP copolymer and studied in terms of morphology, porosity, pore size, hydrophobicity, permeability, and mechanical properties. Different solvents, namely N-Methyl-2 pyrrolidone (NMP), Tetrahydrofuran (THF), and Dimethylformamide (DMF) solvents, were used to fabricate blended PVDF flat sheet membranes without the introduction of any pore forming agent, through a non-solvent induced phase separation (NIPS) technique. Furthermore, the performance of the fabricated membranes was investigated for pressure and thermal driven applications. The porosity of the membranes was slightly increased with the increase in the overall content of PVDF and by the inclusion of PVDF copolymer. Total PVDF content, copolymer content, and mixed-solvent have a positive effect on mechanical properties. The addition of copolymer increased the hydrophobicity when the total PVDF content was 20%. At 25% and with the inclusion of mixed-solvent, the hydrophobicity was adversely affected. The permeability of the membranes increased with the increase in the overall content of PVDF. Mixed-solvents significantly improved permeability.

The Physical and Chemical Properties of Fine Carbon Particles-Pinewood Resin Blends and Their Possible Utilization

Directory of Open Access Journals (Sweden)

Aviwe Melapi

2015-01-01

Full Text Available The application of biomass gasification technology is very important in the sense that it helps to relieve the dwindling supply of natural gas from fossil fuels, and the desired product of its gasification process is syngas. This syngas is a mixture of CO and H2; however, by-products such as char, tar, soot, ash, and condensates are also produced. This study, therefore, investigated selected by-products recovered from the gasification process of pinewood chips with specific reference to their potential application in other areas when used as blends. Three samples of the gasification by-products were obtained from a downdraft biomass gasifier system and were characterized in terms of chemical and physical properties. FTIR analysis confirmed similar spectra in all char-resin blends. For fine carbon particles- (soot- resin blends, almost the same functional groups as observed in char-resin blends appeared. In bomb calorimeter measurements, 70% resin/30% char blends gave highest calorific value, followed by 50% resin/50% soot blends with values of 35.23 MJ/kg and 34.75 MJ/kg consecutively. Provided these by-products meet certain criteria, they could be used in other areas such as varnishes, water purification, and wind turbine blades.

Contributions of blended learning training to teacher professional development

Directory of Open Access Journals (Sweden)

Ana Duarte Hueros

2018-01-01

Full Text Available The central theme of this study is the analysis of a balanced integrated teaching methodology (face-to-face and virtual, as blended learning and the extent of its implementation in teacher training, as well as the importance of leadership in planning, supervising and coordinating this process. We began with a systematic review of the literature of the last 15 years (2002-2017 on the Web of Science (WOS, the most highly rated database in the scientific community. We identified 190 studies related to blended learning, professional teaching development and leadership in education. We then selected 163 documents that fell specifically into the educational research category, of which 75 were articles. We further fine-tuned the search by excluding those articles related to research fields other than teachers’ professional development, and arrived at 35 articles that fulfilled our preliminary criteria. We reduced the sample to the 24 articles that contained all the features required by our investigation. The results show that blended learning is a valuable training tool that enables teachers to acquire competences and which can aid their professional development; it can also foment collaborative work, augment teachers’ technical and didactic skills around technology, promote interdisciplinary experiences and help teachers to share innovations, etc., among other potential outcomes.

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…

Relation between exciplex formation and photovoltaic properties of PPV polymer-based blends

Energy Technology Data Exchange (ETDEWEB)

Yin, Chunhong; Neher, Dieter [Institute of Physics, University of Potsdam, Am Neuen Palais 10, 14469 Potsdam (Germany); Kietzke, Thomas [Institute of Physics, University of Potsdam, Am Neuen Palais 10, 14469 Potsdam (Germany); Institute of Materials Research and Engineering (IMRE), Research Link 3, 117602 Singapore (Singapore); Kumke, Michael [Institute of Chemistry, University of Potsdam, Karl-Liebknecht-Street 24-25, 14476 Golm (Germany); Hoerhold, Hans-Heinrich [Institute of Organic Chemistry and Macromolecular Chemistry, University of Jena, Humboldtstr. 10, 07743 Jena (Germany)

2007-03-06

As a new record for pure polymer-blend solar cells, an energy conversion efficiency (ECE) of 1.7% was recently achieved for M3EH-PPV:CN-ether-PPV (Poly[oxa-1,4-phenylene-1,2-(1-cyano)-ethylene-2,5-dioctyloxy-1,4-phenylene-1,2- (2-cyano)-ethylene-1,4-phenylene]) based devices [T. Kietzke, H.-H. Hoerhold, D. Neher, Chem. Mater. 17 (2005) 6532]. Even though that photoluminescence experiments indicated that 95% of the photogenerated excitions were dissociated in the blend, the external quantum efficiency reached only 31%. Thus more than 2/3 of the dissociated excitons were lost for the energy conversion. In order to identify the processes which limit the photovoltaic efficiency of polymer-blend solar cells, studies on the steady state and time-resolved photoluminescence of the individual polymer and polymer blend were performed. In the polymer-blend layer, we observed a considerable long-wavelength emission due to exciplex formation. The exciplex emission can be reduced by thermal annealing. At the same time the IPCE of the blend-based device increased, indicating a more efficient generation of free-charge carriers. These findings lead to the conclusion that charge-carrier recombination via exciplex formation constitutes one of the loss channels which limits the efficiency of polymer solar cells. (author)

Radio-frequency (RF) studies of the magneto-dielectric composites: Cr{sub 0.75}Fe{sub 1.25}O{sub 3} (CRFO)-Fe{sub 0.5}Cu{sub 0.75}Ti{sub 0.75}O{sub 3} (FCTO)

Energy Technology Data Exchange (ETDEWEB)

Rocha, H.H.B. [Departamento de Engenharia de Teleinformatica (DETI), Universidade Federal do Ceara, Caixa Postal 6007, CEP 60755-640, Fortaleza, CE (Brazil); Laboratorio de Telecomunicacoes e Ciencia e Engenharia dos Materiais (LOCEM), Departamento de Fisica, Universidade Federal do Ceara, Caixa Postal 6030, CEP 60455-760, Fortaleza, CE (Brazil); Freire, F.N.A. [Departamento de Quimica Organica e Inorganica, Universidade Federal do Ceara, CEP 60455-760, Fortaleza, CE (Brazil); Santos, M.R.P.; Sasaki, J.M. [Laboratorio de Telecomunicacoes e Ciencia e Engenharia dos Materiais (LOCEM), Departamento de Fisica, Universidade Federal do Ceara, Caixa Postal 6030, CEP 60455-760, Fortaleza, CE (Brazil); Cordaro, T. [Celestica do Brasil Ltda, Rod Sp 340 km 128.7-Cp 151, CEP 13820-000, Jaguariuna, SP (Brazil); Sombra, A.S.B. [Laboratorio de Telecomunicacoes e Ciencia e Engenharia dos Materiais (LOCEM), Departamento de Fisica, Universidade Federal do Ceara, Caixa Postal 6030, CEP 60455-760, Fortaleza, CE (Brazil)], E-mail: sombra@fisica.ufc.br

2008-08-01

This paper concerns a study about the electrical properties of Cr{sub 0.75}Fe{sub 1.25}O{sub 3} (CRFO)/Fe{sub 0.5}Cu{sub 0.75}Ti{sub 0.75}O{sub 3} (FCTO) magneto-dielectric composites. These compounds were prepared by the conventional solid-state reaction synthesis. The samples synthesized, as well their two-phase composites [Cr{sub 0.75}Fe{sub 1.25}O{sub 3}]{sub Z}-[Fe{sub 0.5}Cu{sub 0.75}Ti{sub 0.75}O{sub 3}]{sub 100-Z} (Z=17, 34, 50, 66, 83), were characterized by X-ray powder diffraction technique (XRD). Rietveld's method was employed to verify the quantitative phase abundances in the composites' and their theoretical densities, which were compared with the experimental densities (pycnometer method). To predict the effect of the phases in the composites effective dielectric function ({kappa}), traditional dielectric mixing models such as parallel, series, and Lichtenecker's model were observed. An alternative approach, a sigmoidal fitting function based on the Boltzmann equation, was proposed to fit the experimental data.

Untreated pain, narcotics regulation, and global health ideologies.

Science.gov (United States)

King, Nicholas B; Fraser, Veronique

2013-01-01

Pain management is marginalized or ignored, with millions of people worldwide unnecessarily living with untreated pain. Reducing global inequalities in untreated pain requires a concerted global effort, say Veronique Fraser and colleagues, which must attend to the complexity of pain and promote multimodal, multidisciplinary pain management.

Computational modelling of Ti50Pt50-xMx shape memory alloys (M: Ni, Ir or Pd and x = 6.25-43.75 at.%)

CSIR Research Space (South Africa)

Modiba, Rosinah M

2017-09-01

Full Text Available The ab initio density functional theory approach was employed to study the effect of Ni, Ir or Pd addition to the TiPt shape memory alloy. The supercell approach in VASP was used to substitute Pt with 6.25, 18.75, 25.00, 31.25 and 43.75 at.% Ni, Ir...

Causes of anorexia in untreated hyperthyroidism: a prospective study.

Science.gov (United States)

Dai, W X; Meng, X W

2000-05-01

Seventeen consecutive patients (mean (SD) 46 (11) years) with untreated hyperthyroidism and anorexia and 29 patients (35 (9) years) with untreated hyperthyroidism without anorexia were studied. The study was conducted at the thyroid clinic of the PUMC Hospital, Beijing, China from March to August 1997. The patients' ages, serum free calcium, liver function and emotional state, specifically the level of anxiety (using the self anxiety scale, Chinese version), were compared before and/or after antithyroid drug treatment in the two groups. This prospective study suggested that the causes of anorexia in untreated hyperthyroidism are complicated. Older age, abnormal liver function, and the level of anxiety are significantly related to anorexia in untreated hyperthyroidism, but hypercalcaemia was not confirmed to be related to anorexia in the study.

LHV predication models and LHV effect on the performance of CI engine running with biodiesel blends

International Nuclear Information System (INIS)

Tesfa, B.; Gu, F.; Mishra, R.; Ball, A.D.

2013-01-01

Highlights: • Lower heating values of neat biodiesel and its blends were measured experimentally. • Lower heating value prediction models were developed based on the density and viscosity values of the fuel. • The predication models were validated by measured values and previous models. • The prediction models were used to predict the lower heating value of 24 biodiesel feedstock types produced globally. • The effects of lower heating vale on brake specific fuel consumption and thermal efficiency were investigated. - Abstract: The heating value of fuel is one of its most important physical properties, and is used for the design and numerical simulation of combustion processes within internal combustion (IC) engines. Recently, there has been a significant increase in the use of dual fuel and blended fuels in compression ignition (CI) engines. Most of the blended fuels include biodiesel as one of the constituents and hence the objective of this study is to investigate the effect of biodiesel content to lower heating value (LHV) and to develop new LHV prediction models that correlate the LHV with biodiesel fraction, density and viscosity. Furthermore, this study also investigated the effects of the LHV on CI engines performance parameters experimentally. To achieve the above mentioned objectives density, viscosity and LHV of rapeseed oil biodiesel, corn oil biodiesel and waste oil biodiesel at different blend fraction values (B0, B5, B10, B20, B50, B75, and B100, where ‘B5’ denotes a blend of 5% biodiesel and 95% mineral diesel, etc.) were measured as per EN ISO 3675:1998, EN ISO 3104:1996 and DIN 51900 standards. The engine experimental work was conducted on a four-cylinder, four-stroke, direct injection (DI) and turbocharged diesel engine by using rapeseed oil and normal diesel blends. Based on the experimental results, models were developed which have the capability to predict the LHV corresponding to different fractions, densities and viscosities of

Effects of Electron Beam Irradiation on Binary Polyamide-6 Blends with Metallocene Copolymers

International Nuclear Information System (INIS)

Rosales, C.

2006-01-01

A versatile way to produce new materials with high Izod impact strength and reduced heat deformations is the irradiation of compatibilized blends. The effect of electron beam irradiation and different types of dispersed phase grafted copolymers on thermal and mechanical properties, and SEM morphology of polyamide-6 (PA-6) blends were investigated. Two metallocene copolymers (mEPDM and mPOE) grafted in-situ with maleic anhydride and two commercial maleated copolymers (EPDM-g-MA and mEPR-g-MA) were employed in binary blends with PA6 as matrix. The blends were prepared by extrusion with a composition of 80 wt. % of PA-6. The influence of the radical or functional groups generated in the grafting and the irradiation processes (25, 50, 100 and 200 kGy) was found by ATR-FTIR. The blends exhibited the characteristic thermal behavior of immiscible systems. All compatibilizers employed influenced the melting and crystallization behavior of the blend components without irradiation and an improvement in interface adhesion was clearly observed by SEM micrographs. The sizes of the dispersed phase in the non-irradiated reactive blends were in agreement with the viscosity ratios of the blend components. High toughness materials were obtained with ethylene-polypropylene-diene (mEPDM) grafted copolymers without significant variations in their thermal properties and Izod impact strength at room temperature and -30 degree with the irradiation doses. However, the toughness of the blends with grafted metallocene polyethylenes was affected by the irradiation doses employed. Therefore, the gel content and tensile properties of the samples depended on the chain scission, crosslinking and/or grafting reactions of the blend components

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

Investigations of mechanical, electronic, and magnetic properties of non-magnetic MgTe and ferro-magnetic Mg0.75TM0.25Te (TM = Fe, Co, Ni): An ab-initio calculation

International Nuclear Information System (INIS)

Mahmood, Q; Alay-e-Abbas, S M; Mahmood, I; Noor, N A; Asif, Mahmood

2016-01-01

The mechanical, electronic and magnetic properties of non-magnetic MgTe and ferro-magnetic (FM) Mg 0.75 TM 0.25 Te (TM = Fe, Co, Ni) in the zinc-blende phase are studied by ab-initio calculations for the first time. We use the generalized gradient approximation functional for computing the structural stability, and mechanical properties, while the modified Becke and Johnson local (spin) density approximation (mBJLDA) is utilized for determining the electronic and magnetic properties. By comparing the energies of non-magnetic and FM calculations, we find that the compounds are stable in the FM phase, which is confirmed by their structural stabilities in terms of enthalpy of formation. Detailed descriptions of elastic properties of Mg 0.75 TM 0.25 Te alloys in the FM phase are also presented. For electronic properties, the spin-polarized electronic band structures and density of states are computed, showing that these compounds are direct bandgap materials with strong hybridizations of TM 3d states and Te p states. Further, the ferromagnetism is discussed in terms of the Zener free electron model, RKKY model and double exchange model. The charge density contours in the (110) plane are calculated to study bonding properties. The spin exchange splitting and crystal field splitting energies are also calculated. The distribution of electron spin density is employed in computing the magnetic moments appearing at the magnetic sites (Fe, Co, Ni), as well as at the non-magnetic sites (Mg, Te). It is found that the p–d hybridization causes not only magnetic moments on the magnetic sites but also induces negligibly small magnetic moments at the non-magnetic sites. (paper)

Diode-pumped passively mode-locked Nd:LuVO4 laser with LT-In0.25Ga0.75As saturable absorber

International Nuclear Information System (INIS)

Li, T; Zhao, S; Li, Y; Zhuo, Z; Yang, K; Li, G; Li, D; Yu, Z

2009-01-01

A diode pumped passively mode-locked Nd:LuVO 4 laser with a low temperature (LT) In 0.25 Ga 0.75 As absorber is realized in this paper. An In 0.25 Ga 0.75 As single-quantum-well absorber, which is grown by use of the metal-organic chemical-vapor deposition technique, acts as nonlinear absorber and output coupler simultaneously. A special cavity is designed to keep the power density on In 0.25 Ga 0.75 As under its damage threshold. Both the Q-switched and continuous-wave (cw) mode locking operation are experimentally realized. An average output power of 5.9 W with pulse width of 4.9 ps is achieved at the pump power of 22 W, corresponding to an optical conversion efficiency of 26.8%

High mobility In0.75Ga0.25As quantum wells in an InAs phonon lattice

Science.gov (United States)

Chen, C.; Holmes, S. N.; Farrer, I.; Beere, H. E.; Ritchie, D. A.

2018-03-01

InGaAs based devices are great complements to silicon for CMOS, as they provide an increased carrier saturation velocity, lower operating voltage and reduced power dissipation (International technology roadmap for semiconductors (www.itrs2.net)). In this work we show that In0.75Ga0.25As quantum wells with a high mobility, 15 000 to 20 000 cm2 V-1 s-1 at ambient temperature, show an InAs-like phonon with an energy of 28.8 meV, frequency of 232 cm-1 that dominates the polar-optical mode scattering from  ˜70 K to 300 K. The measured optical phonon frequency is insensitive to the carrier density modulated with a surface gate or LED illumination. We model the electron scattering mechanisms as a function of temperature and identify mechanisms that limit the electron mobility in In0.75Ga0.25As quantum wells. Background impurity scattering starts to dominate for temperatures  <100 K. In the high mobility In0.75Ga0.25As quantum well, GaAs-like phonons do not couple to the electron gas unlike the case of In0.53Ga0.47As quantum wells.

Percolative nature of A-site disordered La0.75Ca0.25-xSrxMnO3 manganites

DEFF Research Database (Denmark)

Venkatesh, R.; Yadam, Sankararao; Venkateshwarlu, D.

2015-01-01

Magnetic, resistive, and magnetoresistance measurements were used to investigate the percolative nature of A-site disordered La0.75Ca0.25-xSrxMnO3(x = 0, 0.10) manganites. La0.75Ca0.15Sr0.10MnO3 has an orthorhombic structure and second order magnetic phase transition indicates the presence of two...

Fabrication of highly active Melem/Zn0.25Cd0.75S composites for the degradation of bisphenol A and methyl orange under visible light irradiation

International Nuclear Information System (INIS)

Wang, Xiaodong; Yan, Tao; Liu, Xiaohuan; Ji, Pengge; Sun, Meng; Wei, Dong; Yan, Liangguo; Du, Bin

2016-01-01

Highlights: • Novel Melem/Zn 0.25 Cd 0.75 S composite showed enhanced activity in MO degradation. • The composites with melem content of 30 wt.% exhibited the best activity. • The heterojunction was in situ fabricated between melem and Zn 0.25 Cd 0.75 S. • The Melem/Zn 0.25 Cd 0.75 S heterojunction facilitated the separation of electron-hole pairs. - Abstract: Metal-free polymeric catalyst hold great promise owing to their abundant sources, low-cost fabrication and easy processibility. Melem, an important intermediate during condensation of melamine rings to graphitic carbon nitride (g-C 3 N 4 ), was synthesized by simple solid phase polymerization process. A novel Melem/Zn 0.25 Cd 0.75 S composite was fabricated through a facile one-step hydrothermal method. The as-products were characterized by X-ray diffraction (XRD), UV–vis DRS spectroscopy, fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM). The TEM and HRTEM results reveal that Zn 0.25 Cd 0.75 S nanoparticles and Melem closely contact with each other to form an intimate interface. The as-prepared composites exhibit significantly enhanced visible light photocatalytic performance for the degradation of Methyl orange (MO) and Bisphenol A (BPA), which could be attributed to the effective photo-induced charges transfer and separation in Melem/Zn 0.25 Cd 0.75 S composites. On the basis of radical scavenger experiments, superoxide radicals and holes are suggested to play a critical role in MO degradation over Melem/Zn 0.25 Cd 0.75 S heterojunctions. A possible mechanism for charge separation and transfer in the Melem/Zn 0.25 Cd 0.75 S composites was proposed to explain the enhanced photocatalytic performance.

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…

Fe2.25W0.75O4/reduced graphene oxide nanocomposites for novel bifunctional photocatalyst: One-pot synthesis, magnetically recyclable and enhanced photocatalytic property

International Nuclear Information System (INIS)

Guo, Jinxue; Jiang, Bin; Zhang, Xiao; Zhou, Xiaoyu; Hou, Wanguo

2013-01-01

Fe 2.25 W 0.75 O 4 /reduced graphene oxide (RGO) composites were prepared for application of novel bifunctional photocatalyst via simple one-pot hydrothermal method, employing graphene oxide (GO), Na 2 WO 4 , FeSO 4 and sodium dodecyl benzene sulfonate (SDBS) as the precursors. Transmission electron microscope (TEM) results indicate that the well-dispersed Fe 2.25 W 0.75 O 4 nanoparticles were deposited on the surface of RGO sheets homogeneously. Magnetic characterization reveals that Fe 2.25 W 0.75 O 4 and Fe 2.25 W 0.75 O 4 /RGO show ferromagnetic behaviors. So this novel bifunctional photocatalyst could achieve magnetic separation and collection with the aid of external magnet. The composites exhibit enhanced photocatalytic performance on degradation of methyl orange (MO) compared with pure Fe 2.25 W 0.75 O 4 under low-power ultraviolet light irradiation due to the introduction of RGO. Moreover, this hybrid catalyst possesses long-term excellent photocatalytic performance due to its good thermal stability. This bifunctional photocatalyst, which combines magnetic property and excellent photocatalytic activity, would be a perfect candidate in applications of catalytic elimination of environmental pollutants and other areas. - Graphical abstract: Magnetically recyclable Fe 2.25 W 0.75 O 4 /reduced graphene oxide nanocomposites with enhanced photocatalytic property Display Omitted - Highlights: ●Fe 2.25 W 0.75 O 4 growth, deposition and GO reduction occurred simultaneously. ●Composite possessed ferromagnetic and enhanced photocatalytic properties. ●Composite is utilized as a magnetically separable and high-efficient photocatalyst. ●Photocatalyst showed good photocatalytic and thermal stability during cyclic use

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

Estudo comparativo entre bupivacaína a 0,5% e mistura enantiomérica de bupivacaína (S75-R25 a 0,5% em anestesia peridural Estudio comparativo entre bupivacaína a 0,5% y mezcla enantiomérica de bupivacaína (S75-R25 a 0,5% en anestesia peridural Comparative study between 0.5% bupivacaine and 0.5% enantiomeric mixture of bupivacaine (S75-R25 in epidural anesthesia

Directory of Open Access Journals (Sweden)

Rosane Fossatti Gonçalves

2003-04-01

Full Text Available JUSTIFICATIVA E OBJETIVOS: A mistura enantiomérica de bupivacaína (S75-R25 vem sendo empregada pela sua propriedade anestésica com menor toxicidade do que a bupivacaína racêmica. O objetivo deste estudo é comparar a bupivacaína a 0,5% com a mistura enantiomérica de bupivacaína a 0,5% (S75-R25 em anestesia peridural. MÉTODO: Foram incluídos no estudo 44 pacientes divididos em dois grupos (n=22 denominados de Bupivacaína e S75-R25. Os pacientes foram medicados com midazolam por via venosa. A anestesia peridural foi realizada no espaço L3-L4 ou L2-L3, e administrado 16 a 24 ml da solução do anestésico local. O grupo Bupivacaína recebeu bupivacaína a 0,5% com vasoconstritor. O grupo S75-R25 recebeu a mistura enantiomérica de bupivacaína a 0,5% com vasoconstritor. Foram avaliados a temperatura do membro inferior antes e após o bloqueio peridural, o tempo de latência do bloqueio, o tipo de alteração referida pelo paciente, possíveis falhas sensoriais, nível sensorial metamérico e o grau de bloqueio motor. Na sala de recuperação pós-anestésica, foi anotado o tempo de requisição do primeiro analgésico. RESULTADOS: Fizeram parte da avaliação final 41 pacientes. Os grupos foram demograficamente semelhantes. A dose per-operatória de midazolam, o volume de anestésico local por via peridural, o tempo de latência para a instalação do bloqueio, falhas sensoriais a picada da agulha, temperatura do membro inferior nos diferentes tempos, o tipo de sensação parestésica, e o nível anestésico em dermátomos foram semelhantes entre os grupos. O grau de bloqueio motor foi mais intenso para o grupo Bupivacaína, comparado ao grupo S75-R25 (p = 0,0117. O tempo para requisição do primeiro analgésico no período pós-operatório foi superior para o grupo S75-R25, comparado ao grupo Bupivacaína (596 ± 436 minutos versus 463 ± 270 minutos, respectivamente; p = 0,04572. A incidência de efeitos adversos foi semelhante entre

Early-Stage Estimated Value of Blend Sign on the Prognosis of Patients with Intracerebral Hemorrhage

Science.gov (United States)

Zhou, Ningquan; Wang, Chao

2018-01-01

Background and Purpose This study aimed to explore the relationship between blend sign and prognosis of patients with intracerebral hemorrhage (ICH). Methods Between January 2014 and December 2016, the results of cranial computed tomography imaging within 24 h after the onset of symptoms from 275 patients with ICH were retrospectively analyzed. The patients with or without blend sign were compared to observe and analyze the difference in coagulation function abnormality, rebleeding, mortality, and bad prognosis rates in the early stages. Results Of the 275 patients with ICH, 47 patients had Blend Sign I (17.09%) and 17 patients had Blend Sign II (6.18%). The coagulation function abnormality rate had no statistical difference among Blend Sign I, Blend Sign II, and conventional groups (P > 0.05). In the Blend Sign I group, the rebleeding rate was 4.26%, bad prognosis rate was 25.53%, and mortality rate was 6.38%, which were not statistically significantly different compared with those in the conventional group (P > 0.05). The rebleeding rate in the Blend Sign II group was 47.06%, bad prognosis rate was 82.35%, and mortality rate was 47.06%, which were statistically significantly different compared with those in the conventional and Blend Sign I groups (P Blend Sign I, the prognosis was equivalent to that in the conventional group, with no statistically significant difference. The rebleeding, bad prognosis, and mortality rates were higher in the Blend Sign II group than in the conventional group and deserved more attention.

Combustion and emissions characteristics of a compression ignition engine fueled with n-butanol blends

Science.gov (United States)

Yusri, I. M.; Mamat, R.; Ali, O. M.; Aziz, A.; Akasyah, M. K.; Kamarulzaman, M. K.; Ihsan, C. K.; Mahmadul, H. M.; Rosdi, S. M.

2015-12-01

The use of biomass based renewable fuel, n-butanol blends for compression ignition (CI) engine has attracted wide attention due to its superior properties such as better miscibility, higher energy content, and cetane number. In this present study the use of n-butanol 10% blends (Bu10) with diesel fuel has been tested using 4-cylinder, 4-stroke common rail direct injection CI engine to investigate the combustion and emissions of the blended fuels. Based on the tested engine at BMEP=3.5Bar Bu10 fuel indicates lower first and second peak pressure by 5.4% and 2.4% for engine speed 1000rpm and 4.4% and 2.1% for engine speed 2500rpm compared to diesel fuel respectively. Percentage reduction relative to diesel fuel at engine speeds 1000rpm and 2500rpm for Bu10: Exhaust temperature was 7.5% and 5.2% respectively; Nitrogen oxides (NOx) 73.4% and 11.3% respectively.

Emissions of Jatropha oil-derived biodiesel blend fuels during combustion in a swirl burner

Science.gov (United States)

Norwazan, A. R.; Mohd. Jaafar, M. N.; Sapee, S.; Farouk, Hazir

2018-03-01

Experimental works on combustion of jatropha oil biodiesel blends of fuel with high swirling flow in swirl burner have been studied in various blends percentage. Jatropha oil biodiesel was produced using a two-step of esterification-transesterification process. The paper focuses on the emissions of biodiesel blends fuel using jatropha oil in lean through to rich air/fuel mixture combustion in swirl burner. The emissions performances were evaluated by using axial swirler amongst jatropha oil blends fuel including diesel fuel as baseline. The results show that the B25 has good emissions even though it has a higher emission of NOx than diesel fuel, while it emits as low as 42% of CO, 33% of SO2 and 50% of UHC emissions with high swirl number. These are due to the higher oxygen content in jatropha oil biodiesel.

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.

Two DSC Glass Transitions in Miscible Blends of Polyisoprene / Poly(4-tert-butyl styrene)

Science.gov (United States)

Zhao, Junshu; Sun, Ye; Yu, Lian; Ediger, Mark

2009-03-01

Conventional and temperature modulated differential scanning calorimetry experiments have been carried out on miscible blends of polyisoprene (PI) and poly(4-tert-butyl styrene) (P4tBS) over a broad composition range. This system is characterized by an extraordinarily large component Tg difference (˜215 K) between the two homopolymers. Two distinct calorimetric Tgs were observed in blends with an intermediate composition range (25%˜50% PI) by both conventional and temperature modulated DSC. Good agreement was found between the Tg values measured by the two methods. Fitting of the measured Tgs to the Lodge-McLeish model gives a φself of 0.62˜0.64 for PI in this blend and 0.02˜0.05 for P4tBS. The extracted φself for PIis comparable to reported values for PEO in blends with PMMA and is significantly larger than those reported for other PI blends with smaller component Tg differences. This observation suggests the presence of a confinement effect in PI/P4tBS blends, which results in enhanced fast component dynamics below the effective Tg of the slow component.

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.

Fabrication of antibacterial chitosan-PVA blended film using electrospray technique for food packaging applications.

Science.gov (United States)

Liu, Yaowen; Wang, Shuyao; Lan, Wenting

2018-02-01

In this study, blended films from poly(vinyl alcohol) (PVA) containing chitosan (CS) were prepared via a simple solution casting and electrospraying method. The structures of the PVA-CS films were characterized by Fourier-transform infrared spectroscopy. The morphologies of the films were observed by scanning electron microscopy. The thermal properties of the PVA-CS films were examined by thermogravimetry. The effects of CS contents on the mechanical properties, oxygen permeability values, water vapor permeation levels, and antibacterial behaviors against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) strains were investigated. Compared to the pure PVA film, the PVA-CS films showed greater elongation at break, lower oxygen permeability, higher water barrier properties, and greater antibacterial activity, especially for the PVA:CS weight ratio of 75:25. The obtained results indicate the PVA-CS film may be a promising material for food packaging applications. Copyright © 2017 Elsevier B.V. All rights reserved.

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

Cost Comparison Model: Blended eLearning versus traditional training of community health workers.

Science.gov (United States)

Sissine, Mysha; Segan, Robert; Taylor, Mathew; Jefferson, Bobby; Borrelli, Alice; Koehler, Mohandas; Chelvayohan, Meena

2014-01-01

Another one million community healthcare workers are needed to address the growing global population and increasing demand of health care services. This paper describes a cost comparison between two training approaches to better understand costs implications of training community health workers (CHWs) in Sub-Saharan Africa. Our team created a prospective model to forecast and compare the costs of two training methods as described in the Dalburge Report - (1) a traditional didactic training approach ("baseline") and (2) a blended eLearning training approach ("blended"). After running the model for training 100,000 CHWs, we compared the results and scaled up those results to one million CHWs. A substantial difference exists in total costs between the baseline and blended training programs. RESULTS indicate that using a blended eLearning approach for training community health care workers could provide a total cost savings of 42%. Scaling the model to one million CHWs, the blended eLearning training approach reduces total costs by 25%. The blended eLearning savings are a result of decreased classroom time, thereby reducing the costs associated with travel, trainers and classroom costs; and using a tablet with WiFi plus a feature phone rather than a smartphone with data plan. The results of this cost analysis indicate significant savings through using a blended eLearning approach in comparison to a traditional didactic method for CHW training by as much as 67%. These results correspond to the Dalberg publication which indicates that using a blended eLearning approach is an opportunity for closing the gap in training community health care workers.

Sensory evaluation and consumer acceptance of naturally and lactic acid bacteria-fermented pastes of soybeans and soybean–maize blends

Science.gov (United States)

Ng'ong'ola-Manani, Tinna A; Mwangwela, Agnes M; Schüller, Reidar B; Østlie, Hilde M; Wicklund, Trude

2014-01-01

Fermented pastes of soybeans and soybean–maize blends were evaluated to determine sensory properties driving consumer liking. Pastes composed of 100% soybeans, 90% soybeans and 10% maize, and 75% soybeans and 25% maize were naturally fermented (NFP), and lactic acid bacteria fermented (LFP). Lactic acid bacteria fermentation was achieved through backslopping using a fermented cereal gruel, thobwa. Ten trained panelists evaluated intensities of 34 descriptors, of which 27 were significantly different (P consumer (n = 150) heterogeneity in preference, external preference mapping showed that most consumers preferred NFP. Drivers of liking of NFP samples were softness, pH, fermented aroma, sweetness, fried egg aroma, fried egg-like appearance, raw soybean, and rancid odors. Optimization of the desirable properties of the pastes would increase utilization and acceptance of fermented soybeans. PMID:24804070

Reducing the duration of untreated first-episode psychosis

DEFF Research Database (Denmark)

Melle, Ingrid; Larsen, Tor K; Haahr, Ulrik

2004-01-01

Most studies on first-episode psychosis show an association between a long duration of untreated psychosis (DUP) and poorer short-term outcome, but the mechanisms of this relationship are poorly understood.......Most studies on first-episode psychosis show an association between a long duration of untreated psychosis (DUP) and poorer short-term outcome, but the mechanisms of this relationship are poorly understood....

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.

Physicochemical and toxicological characteristics of particulate matter emitted from a non-road diesel engine: comparative evaluation of biodiesel-diesel and butanol-diesel blends.

Science.gov (United States)

Zhang, Zhi-Hui; Balasubramanian, Rajasekhar

2014-01-15

Combustion experiments were conducted to evaluate the effects of using blends of ultralow sulfur diesel (ULSD) with biodiesel or n-butanol on physicochemical and toxicological characteristics of particulate emissions from a non-road diesel engine. The results indicated that compared to ULSD, both the blended fuels could effectively reduce the particulate mass and elemental carbon emissions, with butanol being more effective than biodiesel. The proportion of organic carbon and volatile organic compounds in particles increased for both blended fuels. However, biodiesel blended fuels showed lower total particle-phase polycyclic aromatic hydrocarbons (PAHs) emissions. The total number emissions of particles ≤560nm in diameter decreased gradually for the butanol blended fuels, but increased significantly for the biodiesel blended fuels. Both the blended fuels indicated lower soot ignition temperature and activation energy. All the particle extracts showed a decline in cell viability with the increased dose. However, the change in cell viability among test fuels is not statistically significant different with the exception of DB-4 (biodiesel-diesel blend containing 4% oxygen) used at 75% engine load. Copyright © 2013 Elsevier B.V. All rights reserved.

Distribution pattern of urine albumin creatinine ratio and the prevalence of high-normal levels in untreated asymptomatic non-diabetic hypertensive patients.

Science.gov (United States)

Ohmaru, Natsuki; Nakatsu, Takaaki; Izumi, Reishi; Mashima, Keiichi; Toki, Misako; Kobayashi, Asako; Ogawa, Hiroko; Hirohata, Satoshi; Ikeda, Satoru; Kusachi, Shozo

2011-01-01

Even high-normal albuminuria is reportedly associated with cardiovascular events. We determined the urine albumin creatinine ratio (UACR) in spot urine samples and analyzed the UACR distribution and the prevalence of high-normal levels. The UACR was determined using immunoturbidimetry in 332 untreated asymptomatic non-diabetic Japanese patients with hypertension and in 69 control subjects. The microalbuminuria and macroalbuminuria levels were defined as a UCAR ≥30 and creatinine and a UCAR ≥300 µg/mg·creatinine, respectively. The distribution patterns showed a highly skewed distribution for the lower levels, and a common logarithmic transformation produced a close fit to a Gaussian distribution with median, 25th and 75th percentile values of 22.6, 13.5 and 48.2 µg/mg·creatinine, respectively. When a high-normal UACR was set at >20 to creatinine, 19.9% (66/332) of the hypertensive patients exhibited a high-normal UACR. Microalbuminuria and macroalbuminuria were observed in 36.1% (120/336) and 2.1% (7/332) of the patients, respectively. UACR was significantly correlated with the systolic and diastolic blood pressures and the pulse pressure. A stepwise multivariate analysis revealed that these pressures as well as age were independent factors that increased UACR. The UACR distribution exhibited a highly skewed pattern, with approximately 60% of untreated, non-diabetic hypertensive patients exhibiting a high-normal or larger UACR. Both hypertension and age are independent risk factors that increase the UACR. The present study indicated that a considerable percentage of patients require anti-hypertensive drugs with antiproteinuric effects at the start of treatment.

Impact of promoting longer-lasting insecticide treatment of bed nets upon malaria transmission in a rural Tanzanian setting with pre-existing high coverage of untreated nets

NARCIS (Netherlands)

Russell, T.L.; Lwetoijera, D.W.; Maliti, D.; Chipwaza, B.; Kihonda, J.; Charlwood, J.D.; Smith, T.A.; Lengeler, C.; Mwanyangala, M.A.; Nathan, R.; Knols, B.G.J.; Takken, W.; Killeen, G.F.

2010-01-01

Background The communities of Namawala and Idete villages in southern Tanzania experienced extremely high malaria transmission in the 1990s. By 2001-03, following high usage rates (75% of all age groups) of untreated bed nets, a 4.2-fold reduction in malaria transmission intensity was achieved.

Biodegradable blends of starch/polyvinyl alcohol/glycerol: multivariate analysis of the mechanical properties

Directory of Open Access Journals (Sweden)

Juliano Zanela

Full Text Available Abstract The aim of the work was to study the mechanical properties of extruded starch/polyvinyl alcohol (PVA/glycerol biodegradable blends using multivariate analysis. The blends were produced as cylindrical strands by extrusion using PVAs with different hydrolysis degrees and viscosities, at two extrusion temperature profiles (90/170/170/170/170 °C and 90/170/200/200/200 °C and three conditioning relative humidities of the samples (33, 53, and 75%. The mechanical properties showed a great variability according to PVA type, as well as the extrusion temperature profile and the conditioning relative humidity; the tensile strength ranged from 0.42 to 5.40 MPa, elongation at break ranged from 10 to 404% and Young’s modulus ranged from 0.93 to 13.81 MPa. The multivariate analysis was a useful methodology to study the mechanical properties behavior of starch/PVA/glycerol blends, and it can be used as an exploratory technique to select of the more suitable PVA type and extrusion temperature to produce biodegradable materials.

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

Frequency selective non-linear blending to improve image quality in liver CT

International Nuclear Information System (INIS)

Bongers, M.N.; Bier, G.; Kloth, C.; Schabel, C.; Nikolaou, K.; Horger, M.; Fritz, J.

2016-01-01

To evaluate the effects of a new frequency selective non-linear blending (NLB) algorithm on the contrast resolution of liver CT with low intravascular concentration of iodine contrast. Our local ethics committee approved this retrospective study. The informed consent requirement was waived. CT exams of 25 patients (60% female, mean age: 65±16 years of age) with late phase CT scans of the liver were included as a model for poor intrahepatic vascular contrast enhancement. Optimal post-processing settings to enhance the contrast of hepatic vessels were determined. Outcome variables included signal-to-noise (SNR) and contrast-to-noise ratios (CNR) of hepatic vessels and SNR of liver parenchyma of standard and post-processed images. Image quality was quantified by two independent readers using Likert scales. The post-processing settings for the visualization of hepatic vasculature were optimal at a center of 115HU, delta of 25HU, and slope of 5. Image noise was statistically indifferent between standard and post-processed images. The CNR between the hepatic vasculature (HV) and liver parenchyma could be significantly increased for liver veins (CNR Standard 1.62±1.10, CNR NLB 3.6±2.94, p=0.0002) and portal veins (CNR Standard 1.31±0.85, CNR NLB 2.42±3.03, p=0.046). The SNR of liver parenchyma was significantly higher on post-processed images (SNR NLB 11.26±3.16, SNR Standard 8.85± 2.27, p=0.008). The overall image quality and depiction of HV were significantly higher on post-processed images (NLB DHV : 4 [3-4.75], S tandardDHV : 2 [1.3-2.5], p=<0.0001; NLBIQ : 4 [4-4], StandardIQ : 2 [2-3], p=<0.0001). The use of a frequency selective non-linear blending algorithm increases the contrast resolution of liver CT and can improve the visibility of the hepatic vasculature in the setting of a low contrast ratio between vessels and the parenchyma.

Frequency selective non-linear blending to improve image quality in liver CT

Energy Technology Data Exchange (ETDEWEB)

Bongers, M.N.; Bier, G.; Kloth, C.; Schabel, C.; Nikolaou, K.; Horger, M. [University Hospital of Tuebingen (Germany). Dept. of Diagnostic and Interventional Radiology; Fritz, J. [Johns Hopkins University School of Medicine, Baltimore, MD (United States). Russell H. Morgan Dept. of Radiology and Radiological Science

2016-12-15

To evaluate the effects of a new frequency selective non-linear blending (NLB) algorithm on the contrast resolution of liver CT with low intravascular concentration of iodine contrast. Our local ethics committee approved this retrospective study. The informed consent requirement was waived. CT exams of 25 patients (60% female, mean age: 65±16 years of age) with late phase CT scans of the liver were included as a model for poor intrahepatic vascular contrast enhancement. Optimal post-processing settings to enhance the contrast of hepatic vessels were determined. Outcome variables included signal-to-noise (SNR) and contrast-to-noise ratios (CNR) of hepatic vessels and SNR of liver parenchyma of standard and post-processed images. Image quality was quantified by two independent readers using Likert scales. The post-processing settings for the visualization of hepatic vasculature were optimal at a center of 115HU, delta of 25HU, and slope of 5. Image noise was statistically indifferent between standard and post-processed images. The CNR between the hepatic vasculature (HV) and liver parenchyma could be significantly increased for liver veins (CNR{sub Standard} 1.62±1.10, CNR{sub NLB} 3.6±2.94, p=0.0002) and portal veins (CNR{sub Standard} 1.31±0.85, CNR{sub NLB} 2.42±3.03, p=0.046). The SNR of liver parenchyma was significantly higher on post-processed images (SNR{sub NLB} 11.26±3.16, SNR{sub Standard} 8.85± 2.27, p=0.008). The overall image quality and depiction of HV were significantly higher on post-processed images (NLB{sub DHV}: 4 [3-4.75], S{sub tandardDHV}: 2 [1.3-2.5], p=<0.0001; {sub NLBIQ}: 4 [4-4], {sub StandardIQ}: 2 [2-3], p=<0.0001). The use of a frequency selective non-linear blending algorithm increases the contrast resolution of liver CT and can improve the visibility of the hepatic vasculature in the setting of a low contrast ratio between vessels and the parenchyma.

Polylactic Acid-Based Polymer Blends for Durable Applications

Science.gov (United States)

Finniss, Adam

, showing that no matter the treatment or formulation, PLA achieved a maximum of 30-35 percent crystallinity. Samples receiving no treatment as well as those with annealing, the addition of graphene, and in some cases annealing/graphene were subjected to both solvent and hydrolytic degradation in order to find the most stable blend or treatment. Both pellets and molded parts of varying thicknesses were investigated to evaluate the effect of diffusional resistance on long term durability. It was determined that while the addition of crystallinity or graphene platelets can provide a temporary barrier against diffusion of attacking species, PLA polymer itself is not dimensionally stable over the long lifecycle required for durable applications such as for automotive parts. In fact, PLA-only molded panels aged in distilled water at 50°C for 42 days experienced over 99% viscosity loss regardless of which treatment was applied, and nearly all mechanical strength was lost during this time. Furthermore, while the addition of graphene and the heat treatment produced diffusion barriers which could slightly enhance PLA's degradation resistance, the treatments caused the already fragile polymer to become very brittle. Solvent degradation experiments also showed that molded parts containing more than 40% PLA loading lost in excess of 75% of the original viscosity no matter what treatment was used. This showed that these materials are likely to fail well before a sufficiently long lifecycle for durable goods is achieved. Polycarbonate rich blends with less than 30% PLA as the dispersed phase showed excellent property retention after the accelerated aging tests. Formulations with up to 20% PLA content had degradation results that were nearly identical to those of 100% polycarbonate, which literature has shown to have useful lifecycles for durable applications of up to 20 years. By completely encapsulating the PLA in the polycarbonate matrix, which occurred at about 30% PLA by maximum, it

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.

High-pressure studies of superconductivity in BiO0. 75F0. 25BiS2

Indian Academy of Sciences (India)

). We have investigated the effect of pressure on magnetization measurements. Our studies suggest improved superconducting properties in polycrystalline samples of BiO 0.75 F 0.25 BiS 2 . The Tc in our sample is 5.3 K, at ambient pressure, ...

Partial and Complete Wetting in Ultralow Interfacial Tension Multiphase Blends with Polylactide.

Science.gov (United States)

Zolali, Ali M; Favis, Basil D

2016-12-15

The control of phase structuring in multiphase blends of polylactide (PLA) with other polymers is a viable approach to promote its broader implementation. In this article, ternary and quaternary blends of PLA with poly(butylene succinate) (PBS), poly(butylene adipate-co-terephthalate) (PBAT), and poly(3-hydroxybutyrate-co-hydroxyvalerate) (PHBV) are prepared by melt blending. The interfacial tensions between components are measured using three different techniques, and a Fourier transform infrared imaging technique is developed for the purpose of unambiguous phase identification. A tricontinuous complete wetting behavior is observed for the ternary 33PLA/33PBS/33PBAT blend before and after quiescent annealing, which correlates closely with spreading theory analysis. In the quaternary PLA/PBS/PBAT/PHBV blend, a concentration-dependent wetting behavior is found. At 10 vol % PBAT, self-assembled partially wet droplets of PBAT are observed at the interface of PBS and PHBV, and they remain stable after quiescent annealing as predicted by spreading theory. In contrast, at 25 vol % PBAT, a quadruple continuous system is observed after mixing, which only transforms to partially wet PBAT droplets after subsequent annealing. These results clearly indicate the potential of composition control during the mixing of multiphase systems to result in a complete change of spreading behavior.

Influence of adipic acid on tensile and morphology properties of linear low density polyethylene/rambutan peels flour blends

Science.gov (United States)

Nadhirah, A. A.; Sam, S. T.; Noriman, N. Z.; Ragunathan, S.; Ismail, H.

2015-07-01

This study investigate about the tensile and morphological properties of degradable polymer produced from linear low density polyethylene/rambutan peel flour (LLDPE/RPF) blends and adipic acid (AA) was used as a compatibilizer by varying the rambutan peel flour (RPF) amount from 0-25wt%. The samples were subjected to tensile and morphological tests. AA compatibilized showed higher strength compared to uncompatibilized blends. The Young's modulus for LLDPE/RPF blends increased with increasing flour content. However, the addition of adipic acid had reduced the Young's Modulus.

Hot pressing effect on (Bi 0.25 Sb 0.75 ) 2 Te 3 mechanical and ...

Indian Academy of Sciences (India)

Hot pressing effect on (Bi0.25Sb0.75)2Te3 mechanical and thermoelectric properties ... The crystal of this compound was prepared, pulverized in a particle size ratio of 64% ... microscopy and, for only once successful attempt, atomic force microscopy. The acquired images ensured to show homogeneous structures for hot ...

Homogeneous-inhomogeneous models of Ag x (Ge0.25Se0.75)100-x bulk glasses

International Nuclear Information System (INIS)

Arcondo, B.; Urena, M.A.; Piarristeguy, A.; Pradel, A.; Fontana, M.

2007-01-01

Ge-Se system presents an extensive glass forming composition range even when different metals (Ag, Sb, Bi) are added. In spite that the addition of Ag (up to 30 at%) to Ge-Se does not affect substantially the glass forming tendency, it impacts significantly on the transport properties. (Ge 0.25 Se 0.75 ) 100- x Ag x is a fast ionic conductor with x≥8 at% whereas it is a semiconductor for x 0.25 Se 0.75 ) 100- x Ag x bulk samples. These results appear to sustain this model. However previous structural and thermal studies oppose it. Moessbauer spectrometry on samples (0≤x≤25) containing 0.5 at% of 57 Fe is performed at T≤300 K. The main contribution to the glasses spectra correspond to low spin Fe 2+ in octahedral coordination and high spin Fe 2+ in distorted octahedral environments. The relative population of both sites changes continuously as Ag concentration varies denoting that the change in the transport behavior obeys to a percolation phenomenon. The low temperature results are discussed with the aim to throw light on the controversy about the homogeneity-inhomogeneity of the studied bulk glasses

Fiber-Content Measurement of Wool-Cashmere Blends Using Near-Infrared Spectroscopy.

Science.gov (United States)

Zhou, Jinfeng; Wang, Rongwu; Wu, Xiongying; Xu, Bugao

2017-10-01

Cashmere and wool are two protein fibers with analogous geometrical attributes, but distinct physical properties. Due to its scarcity and unique features, cashmere is a much more expensive fiber than wool. In the textile production, cashmere is often intentionally blended with fine wool in order to reduce the material cost. To identify the fiber contents of a wool-cashmere blend is important to quality control and product classification. The goal of this study is to develop a reliable method for estimating fiber contents in wool-cashmere blends based on near-infrared (NIR) spectroscopy. In this study, we prepared two sets of cashmere-wool blends by using either whole fibers or fiber snippets in 11 different blend ratios of the two fibers and collected the NIR spectra of all the 22 samples. Of the 11 samples in each set, six were used as a subset for calibration and five as a subset for validation. By referencing the NIR band assignment to chemical bonds in protein, we identified six characteristic wavelength bands where the NIR absorbance powers of the two fibers were significantly different. We then performed the chemometric analysis with two multilinear regression (MLR) equations to predict the cashmere content (CC) in a blended sample. The experiment with these samples demonstrated that the predicted CCs from the MLR models were consistent with the CCs given in the preparations of the two sample sets (whole fiber or snippet), and the errors of the predicted CCs could be limited to 0.5% if the testing was performed over at least 25 locations. The MLR models seem to be reliable and accurate enough for estimating the cashmere content in a wool-cashmere blend and have potential to be used for tackling the cashmere adulteration problem.

Gamma and electron beam irradiation effects on SiR-EPDM blends

Directory of Open Access Journals (Sweden)

R. Deepalaxmi

2014-07-01

Full Text Available Ethylene Propylene Diene Monomer (EPDM is widely used as Cable Insulation Material (CIM due to its good mechanical strength. Silicone Rubber (SiR is used in high temperature environments due to its good di-electric properties/hydrophobicity. The blending of SiR-EPDM may result in the improvement in their specific properties. The SiR-EPDM blend of equal composition (50:50 was prepared. When such blends are used as Cable Insulation Materials (CIM, they 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. The short time accelerated testing was carried out, in order to forecast long-term performance of CIM. Electron beam irradiation is widely used in cable manufacturing industries to improve the performance of the polymeric materials. In the current study, on the purpose to investigate the effect of gamma/electron beam irradiation on the 50–50 composition of SiR-EPDM blend, blend was exposed to 25 Mrad dose of gamma/electron beam 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, gamma/electron beam irradiated blends were determined as per ASTM/IEC standards. The nature of degradation was investigated using Fourier Transform Infrared Spectroscopy (FTIR. To determine the elemental composition of the materials at the surface, Energy Dispersive X-ray Analysis (EDAX has been done. Scanning Electron Microscopy (SEM analysis has been done to study the morphological changes. The occurrence of cross-linking is found to be the mechanism for ageing in gamma/electron beam irradiated SiR-EPDM blends.

Structure and magnetism of the Sm{sub 7.5}Y{sub 2.5}Fe{sub 90−x}Si{sub x} (x=0.0, 2.5, 5.0, 7.5 and 10) alloys

Energy Technology Data Exchange (ETDEWEB)

Yang, W.Y.; Zhao, H.; Lai, Y.F.; Du, H.L.; Liu, S.Q.; Wang, C.S.; Han, J.Z.; Yang, Y.C. [State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871 (China); Yu, X.; Qi, Z.Q. [GanZhou Fortune Electronic Co. Ltd., Jiangxi (China); Yang, J.B. [State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter, Beijing (China)

2017-03-15

Sm{sub 7.5}Y{sub 2.5}Fe{sub 90−x}Si{sub x} (x=0.0, 2.5, 5.0, 7.5 and 10) alloys have been prepared by arc melting method and equilibrium disordered Th{sub 2}Zn{sub 17}-type phases, (Sm,Y){sub 2−y}(Fe,Si){sub 17+2y}, with relative lower rare-earth content than the ordered Th{sub 2}Zn{sub 17}-type phase, have been obtained. Compared to the ordered Th{sub 2}Zn{sub 17}-type structure, the X-ray diffraction (XRD) intensity of the superstructure lines of the (Sm,Y){sub 2−y}(Fe,Si){sub 17+2y} decreases with the increase of the Si content and becomes zero for x=10. According to the refinement with the disordered Th{sub 2}Zn{sub 17}-type structure, the occupation rates of the R atoms at (3a) and (6c) sites tend to reach the same value with the increase of the Si content, and the lattice parameter a decreases while the lattice parameter c increases, leading to an increase of c/a. It was found that the atomic ratio of Fe(Si)/Sm(Y) in the disordered Th{sub 2}Zn{sub 17}-type structure increases with the increase of Si content and reaches a maximum value of 9.07 with x=10. The XRD diagrams of the magnetic aligned samples indicate that the easy magnetization direction (EMD) of the (Sm,Y){sub 2−y}(Fe,Si){sub 17+2y} is in the a-b plane, and the change of the EMD in a-b plane has also been observed due to the Si preferred site occupation. The remanence ratios along the easy direction are higher than that along hard direction; however, all the remanence ratios are less than 0.5. The magnetocrystalline anisotropy constant K increases first and then decreases with increasing the Si content. The Curie temperature of Sm{sub 7.5}Y{sub 2.5}Fe{sub 90−x}Si{sub x} alloys increases by about 65 K per Si. The saturation magnetization increases first and then decreases with a maximum of 135.5 emu/g observed for x=2.5 at room temperature. - Highlights: • Equilibrium disordered Th{sub 2}Zn{sub 17}-type phases (Sm,Y){sub 2-y}(Fe,Si){sub 17+2y} have been obtained. • The atomic ratio of

Development and characterization of monolithic fuel miniplate alloy U-2.5Zr-7.5Nb, coated in zircaloy; Desenvolvimento e caracterizacao do combustivel nuclear tipo placa monolitico da liga U-2,5Zr-7,5Nb revestido em zircaloy

Energy Technology Data Exchange (ETDEWEB)

Machado, Geraldo Correa

2014-06-01

The autocthonal production of nuclear fuel in Brazil for test and research reactors is restricted to MTR (Material Test Reactor) fuel type dispersion plate, using U3Si2 alloy, coated and dispersed in aluminum, developed by IPEN-SP for use in IEA-R1 reactor. Moreover, the UO{sub 2} fuel rod type for power reactors is manufactured by Rezende (RJ) with a German technology by INB under license. Currently, Brazil is performing two programs of developing reactors. Currently, Brazil is developing two reactors. One of them is the development, by CNEN, the Brazilian Multipurpose Reactor (RMB), for testing, research and radioisotope production. The other one is the development a power reactor for naval propulsion, conducted by the Brazilian Navy. This dissertation presents the development and characterization of monolithic fuel miniplate alloy U-2.5Zr-7.5Nb, coated in zircaloy (ZRY), on a laboratory scale. Due to its innovative features and properties, this fuel can be used as fuel in both test reactors, research and producing radioisotopes for power reactors as small and medium sizes. Thus, this high potential fuel can be used in domestic reactors currently under development. The development of monolithic fuel plate type is made using the technique called 'picture-frame' where a sandwich composed of a monolith alloy U-2.5Zr- 7.5Nb coupled to a frame and coated sheets of Zry is obtained. The alloy U-2.5Zr-7.5Nb was obtained by melting in an induction furnace and then was cast into rectangular ingots of graphite, thus achieving an ingot with approximate dimensions of 170 x 50 x 60 mm. The obtained ingot was hot rolled at 850 ºC, with a 50 % reduction in thickness, in order to refine the raw structure of fusion. Samples cut from the alloy U-2.5Zr-7.5Nb, with dimensions 20 x 20 x 6 mm were placed in frames and plates Zry and joined by TIG (Tungsten Inert Gas) under an atmosphere of argon, obtaining a set of 10 mm thick, 45 mm wide and 100 mm long. The sandwiches were

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. ...

Microstructural characterisation of Ni75Al25 and Ni31.5Al68.5 powder particles produced by gas atomisation

International Nuclear Information System (INIS)

García-Escorial, A.; Lieblich, M.

2014-01-01

Highlight: ► Successful production of gas atomised Ni75Al25 and Ni31.5Al68.5 powder particles. ► Characterization of the as-solidified microstructure of 75 Al 25 and Ni 31.5 Al 68.5 at.% powder particles below 100 μm in size have been studied. The gas atomised Ni 75 Al 25 powder particles are mainly spherical. The solidification of this alloy is very fast, and its microstructure consists of a dendrite and lamellar structure of partially ordered γ-(Ni), γ′-Ni 3 Al L1 2 phase, and β-NiAl phase. The order increases with the powder particle size. The gas atomised Ni 31.5 Al 68.5 powder particles are also spherical in shape. The microstructure consists of Ni 2 Al 3 dendrites with interdendritic peritectic NiAl 3 and eutectic NiAl 3 + α-Al. The amount of the Ni 2 Al 3 increases as the cooling rate increases. NiAl phase is absent in the gas atomised Ni 31.5 Al 68.5 powder

25 CFR 75.1 - Definitions.

Science.gov (United States)

2010-04-01

... OF CHEROKEE INDIANS, NORTH CAROLINA § 75.1 Definitions. As used in this part: (a) Band means the Eastern Band of Cherokee Indians in North Carolina. (b) Reservation means the lands of the Eastern Band of Cherokee Indians in the counties of Jackson, Swain, Graham, Cherokee and Haywood in North Carolina. (c...

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 ...

Fabrication of highly active Melem/Zn{sub 0.25}Cd{sub 0.75}S composites for the degradation of bisphenol A and methyl orange under visible light irradiation

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiaodong [School of Civil Engineering and Architecture, University of Jinan, Jinan 250022 (China); Yan, Tao, E-mail: yantujn@163.com [School of Resources and Environment, University of Jinan, Jinan 250022 (China); Liu, Xiaohuan; Ji, Pengge [School of Civil Engineering and Architecture, University of Jinan, Jinan 250022 (China); Sun, Meng; Wei, Dong; Yan, Liangguo; Du, Bin [School of Resources and Environment, University of Jinan, Jinan 250022 (China)

2016-11-30

Highlights: • Novel Melem/Zn{sub 0.25}Cd{sub 0.75}S composite showed enhanced activity in MO degradation. • The composites with melem content of 30 wt.% exhibited the best activity. • The heterojunction was in situ fabricated between melem and Zn{sub 0.25}Cd{sub 0.75}S. • The Melem/Zn{sub 0.25}Cd{sub 0.75}S heterojunction facilitated the separation of electron-hole pairs. - Abstract: Metal-free polymeric catalyst hold great promise owing to their abundant sources, low-cost fabrication and easy processibility. Melem, an important intermediate during condensation of melamine rings to graphitic carbon nitride (g-C{sub 3}N{sub 4}), was synthesized by simple solid phase polymerization process. A novel Melem/Zn{sub 0.25}Cd{sub 0.75}S composite was fabricated through a facile one-step hydrothermal method. The as-products were characterized by X-ray diffraction (XRD), UV–vis DRS spectroscopy, fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM). The TEM and HRTEM results reveal that Zn{sub 0.25}Cd{sub 0.75}S nanoparticles and Melem closely contact with each other to form an intimate interface. The as-prepared composites exhibit significantly enhanced visible light photocatalytic performance for the degradation of Methyl orange (MO) and Bisphenol A (BPA), which could be attributed to the effective photo-induced charges transfer and separation in Melem/Zn{sub 0.25}Cd{sub 0.75}S composites. On the basis of radical scavenger experiments, superoxide radicals and holes are suggested to play a critical role in MO degradation over Melem/Zn{sub 0.25}Cd{sub 0.75}S heterojunctions. A possible mechanism for charge separation and transfer in the Melem/Zn{sub 0.25}Cd{sub 0.75}S composites was proposed to explain the enhanced photocatalytic performance.

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.

Martensitic transformation and shape memory effect in Ni54.75Mn13.25Fe7Ga25 ferromagnetic shape memory alloy

International Nuclear Information System (INIS)

Wang, H.B.; Sui, J.H.; Liu, C.; Cai, W.

2008-01-01

The martensitic transformation and shape memory effect of Ni 54.75 Mn 13.25 Fe 7 Ga 25 (at.%) alloy are studied in the present paper. It is shown that tetragonal martensite with parallel bands substructure transforms to parent phase heated by electron beam. It can be clearly observed that the martensite band becomes smaller and smaller, then transforms to parent phase completely in the end. A large reversible transformation strain, about 1.5%, is obtained in this undeformed polycrystalline alloy due to martensitic transformation and its reverse transformation. This transformation strain is also increased to 1.8% by the external magnetic field. It is believed that the effect of the magnetic field on the preferential orientation of martensitic variants increases the transformation strain

Engineering Polymer Blends for Impact Damage Mitigation

Science.gov (United States)

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

2016-01-01

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

Hydrogen storage properties in the Mg{sub 0.75}Ta{sub 0.25} system prepared by mechanical milling; Propiedades de almacenamiento de hidrogeno en el sistema Mg{sub 0.75}Ta{sub 0.25} preparado por molienda mecanica

Energy Technology Data Exchange (ETDEWEB)

Ramirez G, J. A.

2016-07-01

Magnesium and most of its mixtures have slow sorption-desorption kinetics of hydrogen, which limits their technological application and their viability from the economic view point. Recently, has been observed that by the synthesis of advanced materials, using the mechanical milling technique, positive changes in the kinetics are introduced. In order to improve the sorption-desorption hydrogen properties, in the present work a mixture consisting of Mg{sub 0.75}Ta{sub 0.25} was prepared using methanol as process control agent. To this end, the first methodological step was to carry out, by means of the mechanical milling technique, the synthesis of the mixture Mg{sub 0.75}Ta{sub 0.25} in a Spex type vibratory mill at times of 6, 12, 18 and 24 h. Subsequently, the material was characterized by different analytical techniques such as scanning electron microscopy with elemental analysis, X-ray diffraction and N{sub 2} physisorption analysis. Subsequently, hydrogen sorption experiments were carried out in a Parr reactor to evaluate the hydrogen storage capacity of the mixture, varying temperature parameters, pressure and time, in order to determine the optimal parameters of hydrogen sorption. The characterization of the hydrogen storage capacity was analyzed by the thermogravimetric analysis/differential scanning calorimetry technique coupled to a mass spectrometer. X ray diffraction analysis reveals that there is a mixture between the starting compounds, with an important refinement of the microstructure as a consequence of the mechanical milling process. The results of the hydrogen sorption tests at 1, 5 and 10 cycles showed that the storage of hydrogen in the Mg{sub 0.75}Ta{sub 0.25} mixture can be carried out at a temperature of 25 degrees Celsius with a pressure of 2 atm and a contact time of 1 h. (Author)

Phenolic Content of Blends of Tempranillo with Graciano or Cabernet Sauvignon Wines Produced in Spain

Directory of Open Access Journals (Sweden)

María Monagas

2006-01-01

Full Text Available The effect of Graciano (GRA, Spanish valuable variety of limited production in Mediterranean countries vs. Cabernet Sauvignon (CS, world-wide known French variety on the phenolic content [total polyphenols (TP, total anthocyanins (TA, catechins (CAT and proanthocyanidins (PRO] of Tempranillo wines (TEM-BASE, a largely cultivated Spanish variety was studied in blends prepared with 25 and 10 % of each variety after 4, 6, 9, 16.5 and 23 months of bottle ageing. Significant differences among wines (blends and base wine according to the »blend« factor were observed for CAT and TA. Besides, although the evolution trend during wine ageing of different families of phenolic compounds studied was similar in the blends and base wine, different blends presented a faster anthocyanin disappearance kinetics than the base wine, probably due to their higher CAT content, which may favour the progress of certain anthocyanin condensation reactions during ageing in the bottle. This effect was slightly more pronounced in the TEM-GRA blends than in the TEM-CS ones. A further study of the phenolic composition of the monovarietal wines used for blending, as well as of the grapes (skins and seeds from which these wines were elaborated, revealed that the blending effect on CAT could be associated with higher concentration of these compounds in Graciano and Cabernet Sauvignon grape seeds in comparison with Tempranillo. Finally, the findings of this work scientifically confirm that, in terms of the phenolic content, Graciano wines possess properties similar to Cabernet Sauvignon for blending with Tempranillo.

Intake and digestibility of untreated and urea treated rice straw base diet fed to sheep

Directory of Open Access Journals (Sweden)

D Yulistiani

2003-03-01

Full Text Available Rice straw as one of agricultural by-products has low quality due to low content of essensial nutrients like protein, energy, minerals and vitamin as well as poor palatability and digestibility. Therefore, the quality of rice straw needs to be improved in order to increase its utilization by gastrointestinal tract of ruminants. The purpose of this study is to compare untreated and urea treated rice straw as basal diets for sheep. Twelve mature Merino wethers (average body weight 53.62 + 3.44 kg were separated into 4 groups based on their live weight with each groups assigned three diets, that are: diet 1 untreated rice straw with high forage legume content, diet 2 urea ensiled rice straw and diet 3 rice straw sprayed with urea solution at feeding time. Diets were allocated based on a randomized complete block design. Urea ensiled rice straw was prepared by spraying chopped straw with urea solution to yield straw containing 4% urea and 40% moisture, then kept in air tight polythylene bags for 6 weeks. The untreated, ensiled and urea supplemented rice straw were mixed with other feed ingredients to provide isoenergetic and isonitrogenous diets. Diets were formulated to meet maintenance requirement according to NRC. Sheep were adapted to experimental diets for 15 days, and after adaptation period, a metabolism trial was conducted. Results reveal that dry matter intake permetabolic body weight (DMI/W0.75, DE (digestible energi intake and apparent digestibility of NDF (neutral detergent fibre were not significantly different between diet 1 and diet 2. Apparent digestibility of DM (dry matter, OM (organic matter, and ADF (acid detergent fibre, as well as N retention were not significantly different between three diets. Positive result in N retention was only observed in diet 2, while others were negative. It may be concluded from this study that untreated rice straw basal diet supplemented with forage legume offer an alternative method other than urea

Biodegradable Polyphosphazene-Based Blends for Regenerative Engineering.

Science.gov (United States)

Ogueri, Kenneth S; Escobar Ivirico, Jorge L; Nair, Lakshmi S; Allcock, Harry R; Laurencin, Cato T

2017-03-01

The occurrence of musculoskeletal tissue injury or disease and the subsequent functional impairment is at an alarming rate. It continues to be one of the most challenging problems in the human health care. Regenerative engineering offers a promising transdisciplinary strategy for tissues regeneration based on the convergence of tissue engineering, advanced materials science, stem cell science, developmental biology and clinical translation. Biomaterials are emerging as extracellular-mimicking matrices designed to provide instructive cues to control cell behavior and ultimately, be applied as therapies to regenerate damaged tissues. Biodegradable polymers constitute an attractive class of biomaterials for the development of scaffolds due to their flexibility in chemistry and the ability to be excreted or resorbed by the body. Herein, the focus will be on biodegradable polyphosphazene-based blend systems. The synthetic flexibility of polyphosphazene, combined with the unique inorganic backbone, has provided a springboard for more research and subsequent development of numerous novel materials that are capable of forming miscible blends with poly (lactide-co-glycolide) (PLAGA). Laurencin and co-workers has demonstrated the exploitation of the synthetic flexibility of Polyphosphazene that will allow the design of novel polymers, which can form miscible blends with PLAGA for biomedical applications. These novel blends, due to their well-tuned biodegradability, and mechanical and biological properties coupled with the buffering capacity of the degradation products, constitute ideal materials for regeneration of various musculoskeletal tissues. Regenerative engineering aims to regenerate complex tissues to address the clinical challenge of organ damage. Tissue engineering has largely focused on the restoration and repair of individual tissues and organs, but over the past 25 years, scientific, engineering, and medical advances have led to the introduction of this new

Biodegradable Polyphosphazene-Based Blends for Regenerative Engineering

Science.gov (United States)

Ogueri, Kenneth S.; Escobar Ivirico, Jorge L.; Nair, Lakshmi S.; Allcock, Harry R.; Laurencin, Cato T.

2017-01-01

The occurrence of musculoskeletal tissue injury or disease and the subsequent functional impairment is at an alarming rate. It continues to be one of the most challenging problems in the human health care. Regenerative engineering offers a promising transdisciplinary strategy for tissues regeneration based on the convergence of tissue engineering, advanced materials science, stem cell science, developmental biology and clinical translation. Biomaterials are emerging as extracellular-mimicking matrices designed to provide instructive cues to control cell behavior and ultimately, be applied as therapies to regenerate damaged tissues. Biodegradable polymers constitute an attractive class of biomaterials for the development of scaffolds due to their flexibility in chemistry and the ability to be excreted or resorbed by the body. Herein, the focus will be on biodegradable polyphosphazene-based blend systems. The synthetic flexibility of polyphosphazene, combined with the unique inorganic backbone, has provided a springboard for more research and subsequent development of numerous novel materials that are capable of forming miscible blends with poly (lactide-co-glycolide) (PLAGA). Laurencin and co-workers has demonstrated the exploitation of the synthetic flexibility of Polyphosphazene that will allow the design of novel polymers, which can form miscible blends with PLAGA for biomedical applications. These novel blends, due to their well-tuned biodegradability, and mechanical and biological properties coupled with the buffering capacity of the degradation products, constitute ideal materials for regeneration of various musculoskeletal tissues. Lay Summary Regenerative engineering aims to regenerate complex tissues to address the clinical challenge of organ damage. Tissue engineering has largely focused on the restoration and repair of individual tissues and organs, but over the past 25 years, scientific, engineering, and medical advances have led to the introduction of

Effects of the blended fibroin/aloe gel film on wound healing in streptozotocin-induced diabetic rats

International Nuclear Information System (INIS)

Inpanya, Paichit; Viyoch, Jarupa; Faikrua, Atchariya; Ounaroon, Anan; Sittichokechaiwut, Anuphan

2012-01-01

Delayed healing remains a major clinical problem and here we have sought to develop an improved dressing film comprising 1.95% w/v fibroin and 0.05% w/v aloe gel extract. The tensile strength of dry film was 21.1 ± 0.5 MPa and broke at 1.1 ± 0.2% elongation; corresponding values for wet film were 18.3 ± 1.3 MPa and 1.9 ± 0.1%. The film maintained its shape upon water immersion and the swelling ratio of the dry film was 0.8 ± 0.1 while the water uptake was 43.7 ± 2.6%. After 28 days of incubation in phosphate buffered saline (1 M, pH 7.4, 37 °C), the weight of film was reduced by 6.7 ± 1.1% and the tensile strength and elongation at breaking point (dry state) were 15.4 ± 0.6 MPa and 1.5 ± 0.2%, respectively. Compared to aloe-free fibroin film (2.0% fibroin extract only), the blended film enhanced the attachment and proliferation of skin fibroblasts. The bFGF immunofluorescence of fibroblasts cultured on the blended film appeared greater than those cultured on tissue culture plate or on aloe-free fibroin film while α-smooth muscle actin was maintained. In streptozotocin-induced diabetic rats, the wounds dressed with the blended film were smaller (p <0.05) by day 7 after wounding, compared to untreated diabetic wounds. Histology of repaired diabetic wounds showed the fibroblast distribution and collagen fiber organization to be similar to wounds in normal rats, and this was matched by enhanced hydroxyproline content. Thus, such accelerated wound healing by the blended fibroin/aloe gel films may find application in treatment of diabetic non-healing skin ulcers. (paper)

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.

Electrical conductivity studies on Ammonium bromide incorporated with Zwitterionic polymer blend electrolyte for battery application

Science.gov (United States)

Parameswaran, V.; Nallamuthu, N.; Devendran, P.; Nagarajan, E. R.; Manikandan, A.

2017-06-01

Solid polymer blend electrolytes are widely studied due to their extensive applications particularly in electrochemical devices. Blending polymer makes the thermal stability, higher mechanical strength and inorganic salt provide ionic charge carrier to enhance the conductivity. In these studies, 50% polyvinyl alcohol (PVA), 50% poly (N-vinyl pyrrolidone) (PVP) and 2.5% L-Asparagine mixed with different ratio of the Ammonium bromide (NH4Br), have been synthesized using solution casting technique. The prepared PVA/PVP/L-Asparagine/doped-NH4Br polymer blend electrolyte films have been characterized by various analytical methods such as FT-IR, XRD, impedance spectroscopy, TG-DSC and scanning electron microscopy. FT-IR, XRD and TG/DSC analysis revealed the structural and thermal behavior of the complex formation between PVA/PVP/L-Asparagine/doped-NH4Br. The ionic conductivity and the dielectric properties of PVA/PVP/L-Asparagine/doped-NH4Br polymer blend electrolyte films were examined using impedance analysis. The highest ionic conductivity was found to be 2.34×10-4 S cm-1 for the m.wt. composition of 50%PVA:50%PVP:2.5%L-Asparagine:doped 0.15 g NH4Br at ambient temperature. Solid state proton battery is fabricated and the observed open circuit voltage is 1.1 V and its performance has been studied.

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

AKRO/SF: Blend System

Data.gov (United States)

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

Analysis of power tiller noise using diesel-biodiesel fuel blends

Directory of Open Access Journals (Sweden)

N Keramat Siavash

2015-09-01

, capacitor microphone with a unidirectional pattern whose size, sensitivity and frequency range are 1/2", 50 mV Pa-1 and 10 Hz to 20 kHz with a flat extrusion, respectively. Choosing the combination of fuel was carried out according to experiments that have been done before determining engine operation parameters. Results and Discussion: Fuel type has a direct effect on the quality of the IC engine's combustion phenomenon. One of the most important quality parameters that can be fluctuated by fuel type is engine noise. The fuel type has a direct effect on internal fuel ignition engines and affects the quality of fuel ignition. One of the effects of ignition quality is the sound of the engine that is very important in terms of both the health and evaluation of engine performance. Two-wheel tractors are of the most important tools used in agriculture. In addition to agricultural work, they have applications in rural areas as power generators. No research has been carried out so far in Iran on the sound of two-wheel tractors fuelled with diesel and biodiesel fuels. Therefore, the sound of the ignition of biodiesel and diesel mixtures in four stroke, single cylinder, two wheel diesel tractors manufactured by Ashtad Company was studied. The purpose of this study is to analyze the noise parameters of a diesel engine using B0, B5, B10, B15, B20, B25 and B30 biodiesel–diesel blends. Biodiesel was produced from waste oil and blended with net diesel fuel to evaluate the Power tiller's engine noise parameters. This study was carried out at a stationary position and at three positions such as driver's left ear position (DLEP, 1.5 meter (1.5 MAFE and 7.5 meters (7.5 MAFE away from the exhaust at 6 engine speeds (1200, 1400, 1600, 1800, 2000 & 2200 rpm. Statistical analysis and frequency analysis were used to analyze sound of the engine. The results showed that the sound pressure levels of the engine for B10 fuel have the least amount of noise level of the sound pressure. However, this

A nowcasting technique based on application of the particle filter blending algorithm

Science.gov (United States)

Chen, Yuanzhao; Lan, Hongping; Chen, Xunlai; Zhang, Wenhai

2017-10-01

To improve the accuracy of nowcasting, a new extrapolation technique called particle filter blending was configured in this study and applied to experimental nowcasting. Radar echo extrapolation was performed by using the radar mosaic at an altitude of 2.5 km obtained from the radar images of 12 S-band radars in Guangdong Province, China. The first bilateral filter was applied in the quality control of the radar data; an optical flow method based on the Lucas-Kanade algorithm and the Harris corner detection algorithm were used to track radar echoes and retrieve the echo motion vectors; then, the motion vectors were blended with the particle filter blending algorithm to estimate the optimal motion vector of the true echo motions; finally, semi-Lagrangian extrapolation was used for radar echo extrapolation based on the obtained motion vector field. A comparative study of the extrapolated forecasts of four precipitation events in 2016 in Guangdong was conducted. The results indicate that the particle filter blending algorithm could realistically reproduce the spatial pattern, echo intensity, and echo location at 30- and 60-min forecast lead times. The forecasts agreed well with observations, and the results were of operational significance. Quantitative evaluation of the forecasts indicates that the particle filter blending algorithm performed better than the cross-correlation method and the optical flow method. Therefore, the particle filter blending method is proved to be superior to the traditional forecasting methods and it can be used to enhance the ability of nowcasting in operational weather forecasts.

The Laureate English Program: Taking a research informed approach to blended learning

Directory of Open Access Journals (Sweden)

Debra Marsh

2013-02-01

Full Text Available The aim of this case study is to describe the implementation of the Laureate English Program (LEP, the consequent decision to roll out blended learning across the network, and the Laureate-Cambridge University Press research partnership. Phase 1 of the research was completed in September 2012. The goal of this first phase was to gain a general understanding of student profile, computer literacy and competence, student levels of achievement, and student feedback on their blended learning experience. Six hundred and forty-eight students and 35 teachers responded to a questionnaire, which included multiple choice questions and open ended questions requiring extended comment. The questionnaires revealed that less than 25% of the Laureate student group had ever learned a language online before, which impacted significantly on student perception and use of online learning content. Furthermore, the first phase of research has revealed the impact that a complex interplay of different factors has on the relative effectiveness of these blended programs, and it has acknowledged that research is central to informed decision making in order to provide for effective blended learning. DOI: 10.18870/hlrc.v3i1.103

Superconducting nanowire single photon detectors fabricated from an amorphous Mo0.75Ge0.25 thin film

International Nuclear Information System (INIS)

Verma, V. B.; Lita, A. E.; Vissers, M. R.; Marsili, F.; Pappas, D. P.; Mirin, R. P.; Nam, S. W.

2014-01-01

We present the characteristics of superconducting nanowire single photon detectors (SNSPDs) fabricated from amorphous Mo 0.75 Ge 0.25 thin-films. Fabricated devices show a saturation of the internal detection efficiency at temperatures below 1 K, with system dark count rates below 500 cps. Operation in a closed-cycle cryocooler at 2.5 K is possible with system detection efficiencies exceeding 20% for SNSPDs which have not been optimized for high detection efficiency. Jitter is observed to vary between 69 ps at 250 mK and 187 ps at 2.5 K using room temperature amplifiers.

Development and characterization of monolithic fuel miniplate alloy U-2.5Zr-7.5Nb, coated in zircaloy

International Nuclear Information System (INIS)

Machado, Geraldo Correa

2014-01-01

The autocthonal production of nuclear fuel in Brazil for test and research reactors is restricted to MTR (Material Test Reactor) fuel type dispersion plate, using U3Si2 alloy, coated and dispersed in aluminum, developed by IPEN-SP for use in IEA-R1 reactor. Moreover, the UO 2 fuel rod type for power reactors is manufactured by Rezende (RJ) with a German technology by INB under license. Currently, Brazil is performing two programs of developing reactors. Currently, Brazil is developing two reactors. One of them is the development, by CNEN, the Brazilian Multipurpose Reactor (RMB), for testing, research and radioisotope production. The other one is the development a power reactor for naval propulsion, conducted by the Brazilian Navy. This dissertation presents the development and characterization of monolithic fuel miniplate alloy U-2.5Zr-7.5Nb, coated in zircaloy (ZRY), on a laboratory scale. Due to its innovative features and properties, this fuel can be used as fuel in both test reactors, research and producing radioisotopes for power reactors as small and medium sizes. Thus, this high potential fuel can be used in domestic reactors currently under development. The development of monolithic fuel plate type is made using the technique called 'picture-frame' where a sandwich composed of a monolith alloy U-2.5Zr- 7.5Nb coupled to a frame and coated sheets of Zry is obtained. The alloy U-2.5Zr-7.5Nb was obtained by melting in an induction furnace and then was cast into rectangular ingots of graphite, thus achieving an ingot with approximate dimensions of 170 x 50 x 60 mm. The obtained ingot was hot rolled at 850 ºC, with a 50 % reduction in thickness, in order to refine the raw structure of fusion. Samples cut from the alloy U-2.5Zr-7.5Nb, with dimensions 20 x 20 x 6 mm were placed in frames and plates Zry and joined by TIG (Tungsten Inert Gas) under an atmosphere of argon, obtaining a set of 10 mm thick, 45 mm wide and 100 mm long. The sandwiches were hot rolled to

Miscibility of ethyl cellulose/copolyamide6/66/1010 blends by viscometry and refractive index method

Science.gov (United States)

Zhang, Xiuzhen; Shen, Yuhua; Xie, Anjian; Gao, Sulian; Xing, Zhiying

2011-04-01

The miscibility of ethyl cellulose (EC)/copolyamide6/66/1010 (PA-130) in formic acid is studied by viscometry and refractive index techniques at 25°C. Using viscosity data, the criteria Δ b, Δ b', Δ[η]m, interaction parameter μ, β and thermodynamic parameter α are calculated. These investigations indicate that blend of EC/PA-130 is miscible when the ethyl cellulose content is more than 50 wt % in the blend. Further the result was also confirmed by refractive index measurements.

IMPLEMENTATION OF DIOXANE AND DIESEL FUEL BLENDS TO REDUCE EMISSION AND TO IMPROVE PERFORMANCE OF THE COMPRESSION IGNITION ENGINE

Directory of Open Access Journals (Sweden)

SENDILVELAN S.

2017-11-01

Full Text Available Performance of a compression ignition engine fuelled with 1, 4 Dioxane- diesel blends is evaluated. A single-cylinder, air-cooled, direct injection diesel engine developing a power output of 5.2 kW at 1500 rev/min is used. Base data is generated with standard diesel fuel subsequently; five fuel blends namely 90:10, 80:20, 70:30, 60:40 and 50:50 percentages by volume of diesel and dioxane were prepared and tested in the diesel engine. Engine performance and emission data were used to optimize the blends for reducing emission and improving performance. Results show improved performance with B10 blends compared to neat fuel for all conditions of the engine. Other blends recorded marginal decrease in brake thermal efficiency. The maximum efficiency for B30, B50 blends at peak load are 26.3%, 25.2% respectively against 29.1% for sole fuel. NOx emissions were found to be high or the blends. Peak pressure and rate of pressure rise are increased with increase in dioxane ratio due to improved combustion rate. Heat release pattern shows higher premixed combustion rate with the blends. Higher ignition delay and lower combustion duration are found with all blends than neat diesel fuel.

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...

Crystallization of low saturated lipid blends of palm and canola oils with sorbitan monostearate and fully hydrogenated palm oil.

Science.gov (United States)

Barbosa, Karina Martins; Cardoso, Lisandro Pavie; Ribeiro, Ana Paula Badan; Kieckbusch, Theo Guenter; Buscato, Monise Helen Masuchi

2018-03-01

Several scientific investigations have focused on providing new strategies for supporting the development of low saturated and zero trans lipid materials, as healthier fat alternatives for food application. This work evaluated the consistency, crystallization behavior, microstructure and polymorphism of six blends composed of palm and canola oils at different concentrations (100:0, 80:20, 60:40, 40:60, 20:80 and 0:100, in w/w%) added with 5.0% of fully hydrogenated palm oil (FHPO) or with a mixture of 2.5% of FHPO and 2.5% of sorbitan monostearate (SMS). The results were compared with the non-structured blends (standard samples). Through microstructure images, the formation of a more homogeneous and denser packed crystal network was observed for samples added with both crystallization modifiers (FHPO/SMS) compared to the corresponding standard samples, after stabilization at 25 °C during 3 h. In particular, enhanced crystallization modifications were observed for the 40:60 blend, in which the crystal form β' emerged after the addition of FHPO/SMS. Moreover, the 40:60 blend structured with FHPO/SMS showed increased consistency (from 30 to 658 g F /cm 2 ) and induced onset crystallization in a higher temperature (from 13.1 to 23.9 °C) compared with the non-structured one, due to the specific crystallization effects provided by both added structurants.

Relationship between amount of overtime work and untreated decayed teeth in male financial workers in Japan.

Science.gov (United States)

Yoshino, Koichi; Suzuki, Seitaro; Ishizuka, Yoichi; Takayanagi, Atsushi; Sugihara, Naoki; Kamijyo, Hideyuki

2017-05-25

Continuous or frequent overtime work has been shown to have harmful effects on human health. Meanwhile, one of the main reasons for tooth loss is caries. The aim of this study was to assess the relationship between overtime work and untreated decayed teeth in male financial workers. The participants were recruited by applying screening procedures to a pool of Japanese registrants in an online database. Participants filled out a questionnaire about their oral health, behavior, and working conditions. Participants comprised a total of 951 financial male workers, aged 25-64 years. The likelihood of tooth decay increased with amount of overtime work (p=0.002). After adjusting for age, income, educational background, oral hygiene behavior, snacking behavior, regular dental visitation, bad interpersonal relationships at work, and smoking habit, a multiple logistic regression analysis found that participants with 45-80 h of overtime work (odds ratio [OR], 2.56; 95% confidence interval [CI], 1.23-5.33) or over 80 h of overtime work (OR, 3.01; 95% CI, 1.13-7.97) were more likely to have untreated tooth decay. The percentage of participants who gave "too busy with work" as the reason for leaving decayed teeth untreated increased with amount of overtime (p<0.001). These results indicate that overtime work is strongly related to untreated decayed teeth. In addition to oral health education and dental checkups, decreasing stress and decreasing the amount of overtime work may also have a positive effect on oral health in the workplace.

High-pressure studies of superconductivity in BiO0. 75F0. 25BiS2

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science; Volume 40; Issue 6. High-pressure studies of superconductivity in BiO 0.75 F 0.25 BiS 2. ZEBA HAQUE GOHIL S THAKUR GANESAN KALAI SELVAN SONACHALAM ARUMUGAM L C GUPTA A K GANGULI. Volume 40 Issue 6 October 2017 pp 1121-1125 ...

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.

Combustion Characteristics of CI Diesel Engine Fuelled With Blends of Jatropha Oil Biodiesel

Science.gov (United States)

Singh, Manpreet; Yunus Sheikh, Mohd.; Singh, Dharmendra; Nageswara rao, P.

2018-03-01

Jatropha Curcas oil is a non-edible oil which is used for Jatropha biodiesel (JBD) production. Jatropha biodiesel is produced using transesterification technique and it is used as an alternative fuel in CI diesel engine without any hardware modification. Jatropha biodiesel is used in CI diesel engine with various volumetric concentrations (blends) such as JBD5, JBD15, JBD25, JBD35 and JBD45. The combustion parameters such as in-cylinder pressure, rate of pressure rise, net heat release, cumulative heat release, mass fraction burned are analyzed and compared for all blends combustion data with mineral diesel fuel (D100).

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....

Nonlinear image blending for dual-energy MDCT of the abdomen: can image quality be preserved if the contrast medium dose is reduced?

Science.gov (United States)

Mileto, Achille; Ramirez-Giraldo, Juan Carlos; Marin, Daniele; Alfaro-Cordoba, Marcela; Eusemann, Christian D; Scribano, Emanuele; Blandino, Alfredo; Mazziotti, Silvio; Ascenti, Giorgio

2014-10-01

The objective of this study was to compare the image quality of a dual-energy nonlinear image blending technique at reduced load of contrast medium with a simulated 120-kVp linear blending technique at a full dose during portal venous phase MDCT of the abdomen. Forty-five patients (25 men, 20 women; mean age, 65.6 ± 9.7 [SD] years; mean body weight, 74.9 ± 12.4 kg) underwent contrast-enhanced single-phase dual-energy CT of the abdomen by a random assignment to one of three different contrast medium (iomeprol 400) dose injection protocols: 1.3, 1.0, or 0.65 mL/kg of body weight. The contrast-to-noise ratio (CNR) and noise at the portal vein, liver, aorta, and kidney were compared among the different datasets using the ANOVA. Three readers qualitatively assessed all datasets in a blinded and independent fashion. Nonlinear blended images at a 25% reduced dose allowed a significant improvement in CNR (p < 0.05 for all comparisons), compared with simulated 120-kVp linear blended images at a full dose. No statistically significant difference existed in CNR and noise between the nonlinear blended images at a 50% reduced dose and the simulated 120-kVp linear blended images at a full dose. Nonlinear blended images at a 50% reduced dose were considered in all cases to have acceptable image quality. The dual-energy nonlinear image blending technique allows reducing the dose of contrast medium up to 50% during portal venous phase imaging of the abdomen while preserving image quality.

Mistura com excesso enantiomérico de 50% (S75-R25 de bupivacaína complexada com ciclodextrinas e anestesia por via subaracnóidea em ratos Mezcla con exceso enantiomérico de 50% (S75-R25 de bupivacaina con complejo de ciclodextrinas y anestesia por vía subaracnoidea en ratones Complexation of 50% enantiomeric excess (S75-R25 bupivacaine with cyclodextrins and spinal block anesthesia in rats

Directory of Open Access Journals (Sweden)

Daniele Ribeiro de Araujo

2006-10-01

Full Text Available JUSTIFICATIVA E OBJETIVOS: Com a finalidade de prolongar a duração de ação e reduzir a toxicidade sistêmica, têm-se desenvolvido formulações de anestésicos locais (AL complexados com ciclodextrinas (CD. Este estudo realizou a caracterização físico-química e avaliou, em ratos, os efeitos dos complexos de inclusão de bupivacaína racêmica (S50-R50 e da mistura com excesso enantiomérico de 50% (S75-R25 de bupivacaína com hidroxipropil-betaciclodextrina (HP-beta-CD, comparando-os com as soluções atualmente utilizadas na clínica. MÉTODO: Os complexos de inclusão de S75-R25 em HP-beta-CD (razão molar 1:1 foram caracterizados por estudos de solubilidade de fases variando-se as concentrações de HP-beta-CD e a temperatura. Determinaram-se as constantes de afinidade (K pela HP-beta-CD e os parâmetros termodinâmicos para a complexação. Os bloqueios motor e sensitivo foram avaliados, por meio da administração subaracnóidea das formulações na concentração clínica de 0,5%. RESULTADOS: A formação de complexos de inclusão foi observada pelo aumento da solubilidade aquosa do AL sob diferentes temperaturas e concentrações de HP-beta-CD. Os testes in vivo mostraram que S50-R50HP-beta-CD e S75-R25HP-beta-CD reduziram a latência (p JUSTIFICATIVA Y OBJETIVOS: Con la finalidad de prolongar la duración de la acción y reducir la toxicidad sistémica, se han desarrollado formulaciones de AL con complejo de ciclodextrinas (CD. Ese estudio realizó la caracterización físico-química y evaluó en ratones, los efectos de los complejos de inclusión de bupivacaína racémica (S50-R50 y de la mezcla con exceso enantiomérico de 50% (S75-R25 de bupivacaína con hidroxipropil-betaciclodextrina (HP-beta-CD, comparándolos con las soluciones actualmente utilizadas en la clínica. MÉTODO: Los complejos de inclusión de S75-R25 en HP-beta-CD (razón molar 1:1 fueron caracterizados por estudios de solubilidad de fases variando las

Preparation of the PET/PP/PE/EVA polymeric blend from PET bottles and modification studies induced by ionizing radiation; Obtencao da blenda polimerica PET/PP/PE/EVA a partir de garrafas PET e estudo das modificacoes provocadas pela radiacao ionizante

Energy Technology Data Exchange (ETDEWEB)

Rossini, Edvaldo Luis

2005-07-01

The environmental pollution is one of the biggest problems nowadays. Amidst the pollutants, plastic and especially the packings type {sup P}ET bottles{sup ,} which comprise of poly(ethylene terephthalate) (PET), polypropylene (PP), polyethylene (PE) and poly[ethylene-co-(vinyl acetate)] (EVA) are causing big damage in the environment. In this work, the polymeric blend PET/PP/PE/EVA was obtained by a process of simplified mechanical recycling from 'PET bottles' after consumption, with the objective to find solution to this environmental problem. It was also studied the different ionizing radiation doses effects (25, 50, 75, 100, 150, 200, 300, 400 e 500 kGy) on the blend properties using an electron beam accelerator. The mechanical (tensile strength, impact and hardness), thermal (Vicat softening temperature, differential scanning calorimetry and termogravimetric) and microscopic (light microscopy and scanning electron microscopy) properties of the blend were studied. The analysis of the results showed to be a not mixing and compatible blend, with mechanical and thermal properties (which appeared to be similar to the properties of the component material used in the blend in separate) satisfactory, resulting in a resistant material and of low cost, being able to be used in the production of parts that do not demand specifications techniques. The use of the ionizing radiation improved some of the mechanical and thermal properties of the blend (these modifications had been random and irregular, depending directly on the dose of applied radiation and the type of property) making possible more specific applications for this material. (author)

Electric modulus approach to the analysis of electric relaxation in highly conducting (Na{sub 0.75}Bi{sub 0.25})(Mn{sub 0.25}Nb{sub 0.75})O{sub 3} ceramics

Energy Technology Data Exchange (ETDEWEB)

Molak, A; Paluch, M; Pawlus, S; Klimontko, J; Ujma, Z; Gruszka, I [Institute of Physics, University of Silesia, ul. Uniwersytecka 4, PL-40-007 Katowice (Poland)

2005-05-07

Broadband dielectric spectroscopy is applied to investigate the electrical properties of disordered perovskite-like ceramics in a wide temperature range. From the x-ray diffraction analysis it was found that the newly obtained (Na{sub 0.75}Bi{sub 0.25}) (Mn{sub 0.25}Nb{sub 0.75})O{sub 3} ceramics consist of two chemically different phases. The major perovskite one has an orthorhombic structure described by the Pbcm space group (No 57, in yxz setting). The minor phase shows an orthorhombic symmetry, all-face-centred lattice F, with the lattice parameters a = 10.797(4) A, b = 7.601(3) A and c = 7.691(3) A. The electric modulus M{sup *} formalism used in the analysis enabled us to distinguish and separate the relaxation processes, dominated by marked conductivity in the {epsilon}{sup *}({omega}) representation. In the ceramics studied, the relaxation times are thermally activated and the dipole process has a clearly non-Debye behaviour. The relaxation process described with the use of the activation energy of approximately 0.4 eV and the characteristic relaxation time, {tau}{sub 0} = 1 x 10{sup -11} s, was found to be related to oxygen vacancies. The low frequency relaxation shows Debye behaviour with a slightly lower activation energy and a longer characteristic time.

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.

Morphology Evolution of Polycarbonate-Polystyrene Blends During Compounding

DEFF Research Database (Denmark)

Chuai, Chengzhi; Almdal, Kristoffer; Johannsen, Ib

2001-01-01

The morphology evolution of polycarbonate-polystyrene (PC/PS) blends during the compounding process in three blending methods of industrial relevance, namely melt blending, re-melt blending in a twin-screw extruder and tri-melt blending in an injection-moulding machine, was investigated using......-empirical model. The results show that the formation of co-continuous morphology strongly depends on blend composition and melt blending method, whereas the model prediction for phase inversion deviates from the experimental values. Further, we found that the initial mechanism of morphology evolution involves...... scanning electron microscopy (SEM) Co examine nine blend compositions. Blends were prepared at compositions where phase inversion was expected to occur according to model predictions. The experimental results were compared to the values of the point of phase inversion calculated with the semi...

[(Nitrato-κO,O')(nitrito-κO,O')(0.25/1.75)]bis-(1,10-phenanthroline-κN,N')cadmium(II).

Science.gov (United States)

Najafi, Ezzatollah; Amini, Mostafa M; Ng, Seik Weng

2011-01-22

The reaction of cadmium nitrate and sodium nitrite in the presence of 1,10-phenanthroline yields the mixed nitrate-nitrite title complex, [Cd(NO(2))(1.75)(NO(3))(0.25)(C(12)H(8)N(2))(2)]. The metal ion is bis-chelated by two N-heterocycles as well as by the nitrate/nitrite ions in a distorted dodeca-hedral CdN(4)O(4) coordination environment. One nitrite group is ordered; the other is disordered with respect to a nitrate group (ratio 0.75:0.25) concerning the O atom that is not involved in bonding to the metal ion.

Crystal structure and high-temperature properties of the Ruddlesden–Popper phases Sr{sub 3−x}Y{sub x}(Fe{sub 1.25}Ni{sub 0.75})O{sub 7−δ} (0≤x≤0.75)

Energy Technology Data Exchange (ETDEWEB)

Samain, Louise; Amshoff, Philipp [Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm (Sweden); Biendicho, Jordi J. [Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm (Sweden); The ISIS Facility, STFC Rutherford Appleton Laboratory, Didcot OX11 0QX, Oxfordshire (United Kingdom); Tietz, Frank [Institute of Energy and Climate Research, IEK-1, Forschungszentrum Jülich GmbH, D-52425 Jülich (Germany); Mahmoud, Abdelfattah [Jülich Centre for Neutron Science JCNS and Peter Grünberg Institut PGI, JARA-FIT, Forschungszentrum Jülich GmbH, D-52425 Jülich (Germany); Hermann, Raphaël P. [Jülich Centre for Neutron Science JCNS and Peter Grünberg Institut PGI, JARA-FIT, Forschungszentrum Jülich GmbH, D-52425 Jülich (Germany); Faculty of Science, University of Liège, B-4000 Liège (Belgium); Istomin, Sergey Ya. [Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm (Sweden); Department of Chemistry, M.V. Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Grins, Jekabs [Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm (Sweden); Svensson, Gunnar, E-mail: gunnar.svensson@mmk.su.se [Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm (Sweden)

2015-07-15

Ruddlesden–Popper n=2 member phases Sr{sub 3−x}Y{sub x}Fe{sub 1.25}Ni{sub 0.75}O{sub 7−δ}, 0≤x≤0.75, have been investigated by X-ray and neutron powder diffraction, thermogravimetry and Mössbauer spectroscopy. Both samples as-prepared at 1300 °C under N{sub 2}(g) flow and samples subsequently air-annealed at 900 °C were studied. The as-prepared x=0.75 phase is highly oxygen deficient with δ=1, the O1 atom site being vacant, and the Fe{sup 3+}/Ni{sup 2+} ions having a square pyramidal coordination. For as-prepared phases with lower x values, the Mössbauer spectral data are in good agreement with the presence of both 5- and 4-coordinated Fe{sup 3+} ions, implying in addition a partial occupancy of the O3 atom sites that form the basal plane of the square pyramid. The air-annealed x=0.75 sample has a δ value of 0.61(1) and the structure has Fe/Ni ions in both square pyramids and octahedra. Mössbauer spectroscopy shows the phase to contain only Fe{sup 3+}, implying that all Ni is present as Ni{sup 3+}. Air-annealed phases with lower x values are found to contain both Fe{sup 3+} and Fe{sup 4+}. For both the as-prepared and the air-annealed samples, the Y{sup 3+} cations are found to be mainly located in the perovskite block. The high-temperature thermal expansion of as-prepared and air-annealed x=0.75 phases were investigated by high-temperature X-ray diffraction and dilatometry and the linear thermal expansion coefficient determined to be 14.4 ppm K{sup −1}. Electrical conductivity measurements showed that the air-annealed samples have higher conductivity than the as-prepared ones. - Highlights: • Ruddlesden–Popper, n=2, Sr{sub 3−x}Y{sub x}Fe{sub 1.25}Ni{sub 0.75}O{sub 7−δ}, 0≤x≤0.75, have been synthesised. • The crystal structures of the phases have been determined. • Sr{sub 2.25}Y{sub 0.75}Fe{sub 1.25}Ni{sub 0.75}O{sub 6}, made in N{sub 2}(g) has Fe{sup 3+}/Ni{sup 2+} in square pyramides. • Sr{sub 2.25}Y{sub 0.75}Fe{sub 1.25}Ni

Diversity and population dynamics of pests and predators in irrigated rice fields with treated and untreated pesticide.

Science.gov (United States)

Rattanapun, W

2012-01-01

The monitoring of rice pests and their predators in pesticide untreated and treated rice fields was conducted at the southern of Thailand. Twenty-two species in 15 families and 6 orders of rice pests were sampled from untreated rice field. For treated rice field, 22 species in 14 families and 5 orders of rice pest were collected. Regardless of treatment type, dominant species and individual number of rice pest varied to physiological stage of rice. Lepidopteran pests had highest infestation during the vegetative stage of rice growth, while hemipteran pests composed of hopper species (Hemipetra: Auchenorrhyncha) and heteropteran species (Hemiptera: Heteroptera) were dominant groups during the reproductive stage and grain formation and ripening stage of rice growth. In contrast, dominant species of predator did not change throughout rice growing season. There were 35 species in 25 families and seven orders and 40 species in 29 families and seven orders of predators collected from untreated and treated rice field, respectively. Major predators of both rice fields were Micraspis discolor (Fabricius) (Coleoptera: Coccinellidae), Tetragnatha sp. (Araneae: Tetragnathidae) and Agriocnemis pygmaea Rambur (Odonata: Agrionidae). The population dynamic of predators were not related with rice pest population in both treatments. However, the fluctuation of population pattern of rice pests in the untreated treatment were more distinctly synchronized with their predators than that of the treated treatment. There were no significant differences in the total number of rice pest and predator between two treatments at vegetative and reproductive stages of rice growth. Untreated rice field had a higher population number of predator and a lower population number of rice pest than that of treated rice field during grain formation and ripening stages. These results indicated the ago-ecosystem balance in rice fields could be produced through minimal pesticide application, in order to allow

Electrospun nanofibrous SF/P(LLA-CL membrane: a potential substratum for endothelial keratoplasty

Directory of Open Access Journals (Sweden)

Chen JZ

2015-05-01

Full Text Available Junzhao Chen,1,* Chenxi Yan,1,* Mengyu Zhu,1,* Qinke Yao,1 Chunyi Shao,1 Wenjuan Lu,1 Jing Wang,2 Xiumei Mo,2 Ping Gu,1 Yao Fu,1 Xianqun Fan1 1Department of Ophthalmology, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, 2Biomaterials and Tissue Engineering Laboratory, College of Chemistry and Chemical Engineering and Biotechnology, Donghua University, Shanghai, People’s Republic of China *These authors contributed equally to this work Background: Cornea transplant technology has progressed markedly in recent decades, allowing surgeons to replace diseased corneal endothelium by a thin lamellar structure. A thin, transparent, biocompatible, tissue-engineered substratum with corneal endothelial cells for endothelial keratoplasty is currently of interest. Electrospinning a nanofibrous structure can simulate the extracellular matrix and have beneficial effects for cell culture. Silk fibroin (SF has good biocompatibility but poor mechanical properties, while poly(L-lactic acid-co-Ɛ-caprolactone (P(LLA-CL has good mechanical properties but poor biocompatibility. Blending SF with P(LLA-CL can maintain the advantages of both these materials and overcome their disadvantages. Blended electrospun nanofibrous membranes may be suitable for regeneration of the corneal endothelium. The aim of this study was to produce a tissue-engineered construct suitable for endothelial keratoplasty.Methods: Five scaffolds containing different SF:P(LLA-CL blended ratios (100:0, 75:25, 50:50, 25:75, 0:100 were manufactured. A human corneal endothelial (B4G12 cell line was cultured on the membranes. Light transmission, speed of cell adherence, cell viability (live-dead test, cell proliferation (Ki-67, BrdU staining, and cell monolayer formation were detected on membranes with the different blended ratios, and expression of some functional genes was also detected by real-time polymerase chain reaction.Results: Different blended ratios of scaffolds

Influence of storage temperature and time on the physicochemical and bioactive properties of roselle-fruit juice blends in plastic bottle

Science.gov (United States)

Mgaya-Kilima, Beatrice; Remberg, Siv Fagertun; Chove, Bernard Elias; Wicklund, Trude

2014-01-01

Roselle-fruit juice blends were made from roselle extract and mango, papaya, and guava juices at the ratio of 80:20, 60:40, 40:60, and 20:80, % roselle: fruit juice, respectively. The blends were pasteurized at 82.5°C for 20 min and stored in 100 mL plastic bottles at 28 and 4°C for 6 months. The effects of storage time and temperature on physicochemical and bioactive properties were evaluated. Total soluble solids, pH, and reducing sugars increased significantly (P roselle-fruit blends (40% roselle) decreased significantly (P roselle-fruit blends (40% roselle) decreased from 58–55% to 43–42% when stored at 28 and 4°C, respectively. TMA losses were 86–65% at 28°C and 75–53% at 4°C while TPC losses were 66–58% at 28°C and 51–22% at 4°C. Loss of antioxidant capacity (FRAP) was 18–46% at 28°C and 17–35% at 4°C. A principal component analysis (PCA) differentiated roselle-juice fruit blends into two clusters with two principle components PC1 and PC2, which explained 97 and 3% (blends stored at ambient temperature) and 96 and 4% (blends stored at refrigerated temperature) of the variation, respectively. PC1 differentiated roselle-guava juice blends which were characterized by vitamin C, TPC, FRAP, and pH, while PC2 from another cluster of roselle-mango and roselle-papaya juice blends and was characterized by TSS, RS, and color parameters (L* a* b*). However, TMA was the main variable with the highest effect on all roselle-fruit juice blends regardless of the storage time and temperature. PMID:24804077

Scrutinizing the combustion, performance and emissions of safflower biodiesel–kerosene fueled diesel engine used as power source for a generator

International Nuclear Information System (INIS)

Aydın, Hüseyin

2016-01-01

Highlights: • Effects of kerosene addition to biodiesel in a diesel engine were investigated. • S90&K10, S75&K25 and S50&K50 were tested and comparisons have been made with D2. • Patterns of combustion parameters have found be quite similar for blend fuels and D2. • The highest efficiency value is obtained for S50&K50 blend. • HC emissions a bit increased and NOx emissions were decreased. - Abstract: When neat biodiesel or its blends with diesel fuel that contain high amounts of biodiesel are used in diesel engines some operational problems such as poor injection, bad atomization and incomplete combustion occur mainly due to higher viscosity and surface tension. Engine problems with the use of biodiesel–fuel blends that contain higher percentages of biodiesel need to be solved in order to utilize the advantages of biodiesel in environmental and economical ways. The mentioned problems can also be solved by blending biodiesel with another low density or viscosity fuel such as kerosene. In present study biodiesel was produced from safflower oil. S90&K10, S75&K25 and S50&K50 were prepared by blending biodiesel with kerosene. A 4 cylinder diesel engine that was used to drive an electric generator was used to deeply investigate the similarity of combustion, performance and emission characteristics of the blend fuels to D2. All experiments were carried out at constant loads of 3.6, 7.2 and 10.8 kW generated powers. Patterns of combustion parameters found to be quite similar for blends and D2 fuel. NO_x emissions were considerably decreased with percentages of 68.2%, 56.9% and 55.1% for S50&K50, S75&K25 and S90&K10, respectively while unburned HC emissions were a bit increased. Mass fuel consumption and BSFC were slightly increased for S75&K25 and S90&K10, but they were decreased with an average increase in BTE by 3.84% for S50&K50 fuel when compared to D2. Eventually, it was concluded that high percentages of safflower oil biodiesel can be a potential

Hot pressing effect on (Bi0⋅25Sb0⋅75)2Te3 mechanical and ...

Indian Academy of Sciences (India)

Administrator

Abstract. (Bi0⋅25Sb0⋅75)2Te3 thermoelectric material is a well known p type of compound that has higher fig- ... The crystal of this compound was prepared, pulverized in a particle .... ing fracture surfaces of the materials as shown in figures.

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,…

Characterization of starter-free Queso Fresco made with sodium-potassium salt blends over 12 weeks of 4°C storage.

Science.gov (United States)

Van Hekken, D L; Tunick, M H; Renye, J A; Tomasula, P M

2017-07-01

Development of reduced-sodium cheese to meet the demands of consumers concerned about sodium levels in their diet is challenging when a high-moisture, higher pH, fresh cheese, such as Queso Fresco (QF), depends on its NaCl salt content to obtain its signature flavor and quality traits. This study evaluated the effects of different Na-K salt blends on the compositional, sensorial, microbial, functional, and rheological properties of QF stored for up to 12 wk at 4°C. Queso Fresco curd from each vat was divided into 6 portions and salted with different blends of NaCl-KCl (Na-K, %): 0.75-0.75, 1.0-0.5, 1.0-1.0, 1.0-1.3, 1.0-1.5, and 2.0-0 (control). Within this narrow salt range (1.5 to 2.5% total salt), the moisture, protein, fat, and lactose levels; water activity; pH; and the textural and rheological properties were not affected by salt treatment or aging. The total salt, sodium, potassium, and ash contents reflected the different Na-K ratios added to the QF. Total aerobic microbial count, overall proteolysis, the release of casein phosphopeptides, and the level of volatile compounds were affected by aging but not by the salt treatment. Only the 1.0-1.3 and 1.0-1.5 Na-K cheeses had sensory saltiness scores similar to that of the 2.0-0 Na-K control QF. Loss of free serum from the cheese matrix increased steadily over the 12 wk, with higher losses found in QF containing 1.5% total salt compared with the higher Na-K blends. In conclusion, KCl substitution is a viable means for reduction of sodium in QF resulting in only minor differences in the quality traits, and levels of 1.0-1.3 and 1.0-1.5 Na-K are recommended to match the saltiness intensity of the 2.0-0 Na-K control. The findings from this study will aid cheese producers in creating reduced-sodium QF for health-conscious consumers. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Radiation resistant polypropylene blended with mobilizer,. antioxidants and nucleating agent

Science.gov (United States)

Shamshad, A.; Basfar, A. A.

2000-03-01

Post-irradiation storage of medical disposables prepared from isotactic polypropylene renders them brittle due to degradation. To avoid this, isotactic polypropylene [(is)PP] was blended with a mobilizer, dioctyl pthallate (DOP), three antioxidants (hindered amines and a secondary antioxidant) and benzoic acid to obtain radiation-resistant, thermally-stable and transparent material. Different formulations prepared were subjected to gamma radiation to doses of 25 and 50 kGy. Tests of breakage on bending after ageing in an oven at 70°C up to 12 months have shown that the addition of DOP and the antioxidants imparts improved radiation and thermal stability as compared to (is)PP alone or its blend with DOP. All the formulations irradiated or otherwise demonstrated excellent colour stability even after accelerated ageing at 70°C for prolonged periods.

Comparative evaluation of untreated and radurized Chilean avocadoes shipped to the Netherlands

International Nuclear Information System (INIS)

Ang, L.A.; Uzcategui, E.; Farkas, J.; Langerak, D.Is.; Duren, M.D.A.; Rubio, C.T.

1986-01-01

Avocados of Fuerte variety were picked mature green, treated with a hot water dip (10 min at 46 deg C) then individually wrapped in PVC foil, irradiated with a gamma radiation dose of 25 Gy, shipped by boat at 7 deg C from Chile to the Netherlands and stored there under different conditions. Similarly packed untreated fruits served as controls. The combination treatment and wrapping in PVC foil delayed and reduced the decay, and resulted in a better consumer quality. This small-scale trial shipment holds promise that a sea-transport of combined treated avocados from Chile to Western Europe whould be feasible. (author)

25 CFR 75.19 - Distribution of judgment funds.

Science.gov (United States)

2010-04-01

... ROLL OF THE EASTERN BAND OF CHEROKEE INDIANS, NORTH CAROLINA § 75.19 Distribution of judgment funds. The membership roll of the Eastern Band of Cherokee Indians of North Carolina will be brought up to... shall be in accordance with regulations in this part 75, except as otherwise provided in paragraphs (b...

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.

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)

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.

Flexural properties of treated and untreated kenaf/epoxy composites

International Nuclear Information System (INIS)

Yousif, B.F.; Shalwan, A.; Chin, C.W.; Ming, K.C.

2012-01-01

Graphical abstract: Untreated kenaf fibre/epoxy composites. Treated kenaf fibre/epoxy composites. Highlights: ► Treatment of kenaf fibres with 6% NaOH has improved the flexural properties of epoxy composites. ► Interfacial adhesion of the natural fibres is controlled by the microstructure of the fibres. ► Kenaf fibres have a potential to replace glass fibres for flexural applications. -- Abstract: In the current work, flexural properties of unidirectional long kenaf fibre reinforced epoxy (KFRE) composites are studied. The kenaf fibres were prepared into two types as untreated and treated (with 6% NaOH). The failure mechanism and damage features of the materials were categorized with the surface observation by scanning electron microscope (SEM). The results revealed that reinforcement of epoxy with treated kenaf fibres increased the flexural strength of the composite by about 36%, while, untreated fibres introduced 20% improvement. This was mainly due to the high improvement of the chemical treatment (NaOH) on the interfacial adhesion of the fibres and the porosity of the composites which prevented the debonding, detachments or pull out of fibres. For untreated KFRE, the fracture mechanisms were debonding, tearing, detachments and pull out of fibres. The developed composite exhibited superior properties compared to the previous composites based on natural and synthetic fibres.

Prediction of the burnout behaviour of chars derived from coal-biomass blends

Energy Technology Data Exchange (ETDEWEB)

Tao Wu; Mei Gong; Edward Lester [University of Nottingham, Nottingham (United Kingdom). School of Chemical, Environmental and Mining Engineering

2007-07-01

Nowadays, biomass has been considered an alternative fuel to coal and is being used in power plants to replace part of coal used. This study is to investigate the potential of burning biomass with coal and its impacts on burnout levels. Daw Mill coal was selected for burnout modelling together with three biomasses, Cereal, PKE and Olive Cake. Chars were prepared (75-106 micron) and characterised using image analysis methods as in input data into the char burnout model (ChB) which was adapted to allow the prediction of char burnout of biomass-coal blends under typical pf combustion conditions. The burnout performance of four blend compositions for each biomass were modelled (5%, 10%, 20% and 30%). In practice, the low heating-value of biomass produces a lower flame temperature which can lead to lower levels of char burn-out. The effect is closely linked with the type of biomass used. 36 refs., 4 figs., 1 tab.

Blended care vs. usual care in the treatment of depressive symptoms and disorders in general practice [BLENDING]: study protocol of a non-inferiority randomized trial.

Science.gov (United States)

Massoudi, Btissame; Blanker, Marco H; van Valen, Evelien; Wouters, Hans; Bockting, Claudi L H; Burger, Huibert

2017-06-13

The majority of patients with depressive disorders are treated by general practitioners (GPs) and are prescribed antidepressant medication. Patients prefer psychological treatments but they are under-used, mainly due to time constraints and limited accessibility. A promising approach to deliver psychological treatment is blended care, i.e. guided online treatment. However, the cost-effectiveness of blended care formatted as an online psychological treatment supported by the patients' own GP or general practice mental health worker (MHW) in routine primary care is unknown. We aim to demonstrate non-inferiority of blended care compared with usual care in patients with depressive symptoms or a depressive disorder in general practice. Additionally, we will explore the real-time course over the day of emotions and affect, and events within individuals during treatment. This is a pragmatic non-inferiority trial including 300 patients with depressive symptoms, recruited by collaborating GPs and MHWs. After inclusion, participants are randomized to either blended care or usual care in routine general practice. Blended care consists of the 'Act and Feel' treatment: an eight-week web-based program based on behavioral activation with integrated monitoring of depressive symptomatology and automatized feedback. GPs or their MHWs coach the participants through regular face-to-face or telephonic consultations with at least three sessions. Depressive symptomatology, health status, functional impairment, treatment satisfaction, daily activities and resource use are assessed during a follow-up period of 12 months. During treatment, real-time fluctuations in emotions and affect, and daily events will be rated using ecological momentary assessment. The primary outcome is the reduction of depressive symptoms from baseline to three months follow-up. We will conduct intention-to-treat analyses and supplementary per-protocol analyses. This trial will show whether blended care might be an

A Systematic Review of Mortality from Untreated Scrub Typhus (Orientia tsutsugamushi.

Directory of Open Access Journals (Sweden)

Andrew J Taylor

Full Text Available Scrub typhus, a bacterial infection caused by Orientia tsutsugamushi, is increasingly recognized as an important cause of fever in Asia, with an estimated one million infections occurring each year. Limited access to health care and the disease's non-specific symptoms mean that many patients are undiagnosed and untreated, but the mortality from untreated scrub typhus is unknown. This review systematically summarizes the literature on the untreated mortality from scrub typhus and disease outcomes.A literature search was performed to identify patient series containing untreated patients. Patients were included if they were symptomatic and had a clinical or laboratory diagnosis of scrub typhus and excluded if they were treated with antibiotics. The primary outcome was mortality from untreated scrub typhus and secondary outcomes were total days of fever, clinical symptoms, and laboratory results. A total of 76 studies containing 89 patient series and 19,644 patients were included in the final analysis. The median mortality of all patient series was 6.0% with a wide range (min-max of 0-70%. Many studies used clinical diagnosis alone and had incomplete data on secondary outcomes. Mortality varied by location and increased with age and in patients with myocarditis, delirium, pneumonitis, or signs of hemorrhage, but not according to sex or the presence of an eschar or meningitis. Duration of fever was shown to be long (median 14.4 days Range (9-19.Results show that the untreated mortality from scrub typhus appears lower than previously reported estimates. More data are required to clarify mortality according to location and host factors, clinical syndromes including myocarditis and central nervous system disease, and in vulnerable mother-child populations. Increased surveillance and improved access to diagnostic tests are required to accurately estimate the untreated mortality of scrub typhus. This information would facilitate reliable quantification of

A Systematic Review of Mortality from Untreated Scrub Typhus (Orientia tsutsugamushi).

Science.gov (United States)

Taylor, Andrew J; Paris, Daniel H; Newton, Paul N

2015-01-01

Scrub typhus, a bacterial infection caused by Orientia tsutsugamushi, is increasingly recognized as an important cause of fever in Asia, with an estimated one million infections occurring each year. Limited access to health care and the disease's non-specific symptoms mean that many patients are undiagnosed and untreated, but the mortality from untreated scrub typhus is unknown. This review systematically summarizes the literature on the untreated mortality from scrub typhus and disease outcomes. A literature search was performed to identify patient series containing untreated patients. Patients were included if they were symptomatic and had a clinical or laboratory diagnosis of scrub typhus and excluded if they were treated with antibiotics. The primary outcome was mortality from untreated scrub typhus and secondary outcomes were total days of fever, clinical symptoms, and laboratory results. A total of 76 studies containing 89 patient series and 19,644 patients were included in the final analysis. The median mortality of all patient series was 6.0% with a wide range (min-max) of 0-70%. Many studies used clinical diagnosis alone and had incomplete data on secondary outcomes. Mortality varied by location and increased with age and in patients with myocarditis, delirium, pneumonitis, or signs of hemorrhage, but not according to sex or the presence of an eschar or meningitis. Duration of fever was shown to be long (median 14.4 days Range (9-19)). Results show that the untreated mortality from scrub typhus appears lower than previously reported estimates. More data are required to clarify mortality according to location and host factors, clinical syndromes including myocarditis and central nervous system disease, and in vulnerable mother-child populations. Increased surveillance and improved access to diagnostic tests are required to accurately estimate the untreated mortality of scrub typhus. This information would facilitate reliable quantification of DALYs and

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)

The effect of Moidal non-linear blending function for dual-energy CT on CT image quality

International Nuclear Information System (INIS)

Zhang Fan; Yang Li

2011-01-01

Objective: To compare the difference between linear blending and non-linear blending function for dual-energy CT, and to evaluate the effect on CT image quality. Methods: The model was made of a piece of fresh pork liver inserted with 5 syringes containing various concentrations of iodine solutions (16.3, 26.4, 48.7, 74.6 and 112.3 HU). Linear blending images were automatically reformatted after the model was scanned in the dual-energy mode. Non-linear blending images were reformatted using the software of optimal contrast in Syngo workstation. Images were divided into 3 groups, including linear blending group, non-linear blending group and 120 kV group. Contrast noise ratio (CNR) were measured and calculated respectively in the 3 groups and the different figure of merit (FOM) values between the groups were compared using one-way ANOVA. Twenty patients scanned in the dual-energy mode were randomly selected and the SNR of their liver, renal cortex, spleen, pancreas and abdominal aorta were measured. The independent sample t test was used to compare the difference of signal to noise ratio (SNR) between linear blending group and non linear blending group. Two readers' agreement score and single-blind method were used to investigate the conspicuity difference between linear blending group and non linear blending group. Results: With models of different CT values, the FOM values in non-linear blending group were 20.65± 8.18, 11.40±4.25, 1.60±0.82, 2.40±1.13, 45.49±17.86. In 74.6 HU and 112.3 HU models, the differences of the FOM values observed among the three groups were statistically significant (P<0.05), which were 0.30±0.06 and 14.43±4.59 for linear blending group, and 0.22±0.05 and 15.31±5.16 for 120 kV group. And non-linear blending group had a better FOM value. The SNR of renal cortex and abdominal aorta were 19.2±5.1 and 36.5±13.9 for non-linear blending group, while they were 12.4±3.8 and 22.6±7.0 for linear blending group. There were statistically

Immunological responses, histopathological finding and disease resistance of blue mussel (Mytilus edulis) exposed to treated and untreated municipal wastewater

International Nuclear Information System (INIS)

Akaishi, Fabiola M.; St-Jean, Sylvie D.; Bishay, Farida; Clarke, John; Rabitto, Ines da S.; Oliveira Ribeiro, Ciro A. de

2007-01-01

This study provides new information on the response of the immune system of Mytilus edulis exposed to untreated and treated sewage, linking immune response to ecologically relevant endpoints, such as disease resistance. Our goal was to assess the potential effects of sewage on the immune system (phagocytic activity and production of cytotoxic metabolites, disease resistance) and gills (light microscope) of mussels through a bioassay and field study in an estuarine receiving environment (RE). A semi-static experiment was developed in a wastewater treatment plant in New Glasgow, NS Canada. Mussels were exposed for 21 days to 12.5%, 25%, 50% and 100% of untreated sewage influent and artificial seawater control. Sampling occurred after 7, 14 and 21 days of exposure. In the field study, eight sites were selected in East River and Pictou Harbour, NS, positioned upstream and downstream of sewage effluents outfalls. Caged mussels were exposed to the RE for 90 days (May-July 2005). Mussels were challenged to test their efficiency at eliminating the bacteria, Listonella anguillarium in the bioassay and field studies. The bioassay results showed that higher concentrations of untreated sewage could modulate the immune system of mussels through increased of phagocytic activity (PA), nitric oxide (NO) and hydrogen peroxide (H 2 O 2 ) production during 14 days of exposure, and decreased activity and production at 21 days, with the exception of H 2 O 2 production which was high even at 21 days. Mussels exposed to untreated sewage RE also presented a high PA, NO and H 2 O 2 production and lower number of haemocytes compared to mussels from reference sites. In the bacterial challenge, mussels pre-exposed to 100% sewage died 24 h after being infected with L. anguillarium, while mussels pre-exposed to 50% eliminated bacteria had a mortality rate of 30%. Mussels from the control, 12.5% and 25% groups eliminated bacteria and no mortality was observed. No significant difference was

Sensitivity and specificity of Frontal Assessment Battery in newly diagnosed and untreated obstructive sleep apnea patients.

Science.gov (United States)

Ladera, Valentina; Sargento, Paulo; Perea, Victoria; Faria, Miguel; Garcia, Ricardo

2018-02-01

Executive dysfunction (ED) is often observed in subjects diagnosed with obstructive sleep apnea (OSA), but their assessment requires facilities that are not always available. We aim to evaluate the extent to which Frontal Assessment Battery (FAB) discriminates ED in newly diagnosed, untreated, and without-comorbidity OSA patients. Sixty subjects participated in the study. Of these, 40 (31 males and 9 females) were newly diagnosed for OSA through full-night polysomnography (apnea/hypopnea index; M = 39.01, SD = 27.16), untreated, with a mean age of 54.50 years (SD = 8.90), while the remaining 20 (15 males and 5 females) had no symptoms of OSA (M = 51.60 years, SD = 10.70). The instruments used were the following: Questionnaire for Sleep Apnea Risk, Epworth Sleepiness Scale, Mini-Mental State Examination, and FAB. The group with OSA exhibited significantly lower values in the FAB global score (p = 0.003) and in Conceptualization (p = 0.001) and Mental Flexibility (p = 0.009) subtests. ROC analysis showed adequate discriminative capacity for the FAB global score (AUC = 0.74) and for Conceptualization (AUC = 0.75) and Mental Flexibility (AUC = 0.70) scores. The FAB is a short and no-time-consuming tool that can be used to investigate the presence of ED in untreated OSA patients with no comorbidities, providing clinicians with a simple and effective way of detecting the presence of this dysfunction and allowing a more informed decision for the need of a full neuropsychological assessment. Copyright © 2017 Elsevier B.V. All rights reserved.

Regulated and unregulated emissions from a diesel engine fueled with diesel fuel blended with diethyl adipate

Science.gov (United States)

Zhu, Ruijun; Cheung, C. S.; Huang, Zuohua; Wang, Xibin

2011-04-01

Experiments were carried out on a four-cylinder direct-injection diesel engine operating on Euro V diesel fuel blended with diethyl adipate (DEA). The blended fuels contain 8.1%, 16.4%, 25% and 33.8% by volume fraction of DEA, corresponding to 3%, 6%, 9% and 12% by mass of oxygen in the blends. The engine performance and exhaust gas emissions of the different fuels were investigated at five engine loads at a steady speed of 1800 rev/min. The results indicated an increase of brake specific fuel consumption and brake thermal efficiency when the engine was fueled with the blended fuels. In comparison with diesel fuel, the blended fuels resulted in an increase in hydrocarbon (HC) and carbon monoxide (CO), but a decrease in particulate mass concentrations. The nitrogen oxides (NO x) emission experienced a slight variation among the test fuels. In regard to the unregulated gaseous emissions, formaldehyde and acetaldehyde increased, while 1,3-butadiene, ethene, ethyne, propylene and BTX (benzene, toluene and xylene) in general decreased. A diesel oxidation catalyst (DOC) was found to reduce significantly most of the investigated unregulated pollutants when the exhaust gas temperature was sufficiently high.

Causes of anorexia in untreated hyperthyroidism: a prospective study

OpenAIRE

Dai, W.; Meng, X.

2000-01-01

Seventeen consecutive patients (mean (SD) 46 (11) years) with untreated hyperthyroidism and anorexia and 29 patients (35 (9) years) with untreated hyperthyroidism without anorexia were studied. The study was conducted at the thyroid clinic of the PUMC Hospital, Beijing, China from March to August 1997. The patients' ages, serum free calcium, liver function and emotional state, specifically the level of anxiety (using the self anxiety scale, Chinese version), were compared before and/or after ...

Disparities in untreated caries among children and adults in the U.S., 2011-2014.

Science.gov (United States)

Gupta, Niodita; Vujicic, Marko; Yarbrough, Cassandra; Harrison, Brittany

2018-03-06

The Affordable Care Act of 2010 increased dental coverage for children in the United States, (U.S.) but not for adults. Few studies in current scholarship make use of up-to-date, nationally representative data to examine oral health disparities in the U.S. The purpose of this study is to use nationally representative data to determine the prevalence of untreated caries among children and adults of different socioeconomic and racial/ethnic groups and to examine the factors associated with untreated caries among children and adults. This study used the 2011-2014 National Health and Nutrition Examination Survey (NHANES) demographic, oral health questionnaire, and oral health dentition examination data (n = 7008 for children; n = 9673 for adults). Participants that had a standardized oral health examination and at least one natural primary or permanent tooth considering 28 tooth spaces were included in this study. Our main outcome measure was untreated coronal caries defined as decay on the crown or enamel surface of a tooth that had not been treated or filled. Population estimates were calculated to determine the prevalence of untreated caries among children and adults in the United States. Frequencies and Pearson's chi-square tests were used to compare those with and without untreated caries. Multivariate logistic regression models were used to evaluate the factors associated with untreated caries. We conducted analyses among children and adults separately. From 2011 to 2014, 12.4 million children and 57.6 million adults in the United States had untreated caries. Age, family income level, recent dental visit, and financial and non-financial barriers were significantly associated with untreated caries in both children and adults. Race/ethnicity, gender and education level were also significantly associated with untreated caries among adults. The odds of untreated caries associated with financial barriers were 2.06 for children and 2.84 for adults while the

Structure and magnetic properties of Ba5Ce1.25Mn3.75O15, a new 10H-polytype in the Ba–Ce–Mn–O system

International Nuclear Information System (INIS)

Macías, Mario A.; Mentré, Olivier; Colis, Silviu; Cuello, Gabriel J.; Gauthier, Gilles H.

2013-01-01

Based on the peculiar magnetic properties that are observed in pseudo one-dimensional manganites, we decided to synthesize the new Ba 5 Ce 1.25 Mn 3.75 O 15 compound. The preparation was performed by solid state reaction in air at about 1350 °C, for which we found that the compound crystallizes in a hexagonal symmetry with space group P6 3 /mmc (No-194) and cell parameters a=b=5.7861(2) Å and c=23.902(1) Å. The structural description was correlated with neutron diffraction and bond valence calculations, confirming the presence of Ce 4+ and Mn 4+ segregated in the different crystallographic positions. Ba 5 Ce 1.25 Mn 3.75 O 15 displays evidence for strong AFM couplings already set at room temperature. The main arrangement of Mn 4+ in magnetically isolated tetramers of face-sharing octahedra is responsible for a metamagnetic-like transition around 50 K. - Graphical abstract: The new Ba 5 Ce 1.25 Mn 3.75 O 15 polytype shows strong AFM couplings in magnetically isolated [Ce 0.25 Mn 3.75 O 15 ] tetramers of face-sharing octahedral, resulting in a metamagnetic-like transition around 50 K. Highlights: ► Ba 5 Ce 1.25 Mn 3.75 O 15 , a new 10H polytype, has been prepared in the Ba–Ce–Mn–O system. ► The compound crystallizes in the P6 3 /mmc space group with (cchhh) 2 stacking sequence. ► [Ce 0.25 Mn 3.75 O 15 ] tetramers are separated by [CeO 6 ] octahedra in the structure. ► Instead of robust AFM ordering, a metamagnetic-like transition is found around 50 K.

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

Efficient internal and surface fingerprint extraction and blending using optical coherence tomography.

Science.gov (United States)

Darlow, Luke Nicholas; Connan, James

2015-11-01

Optical coherence tomography provides a 3D representation of fingertip skin where surface and internal fingerprints are found. These fingerprints are topographically identical. However, the surface skin is prone to damage, distortion, and spoofing; and the internal fingerprint is difficult to access and extract. This research presents a novel scaling-resolution approach to fingerprint zone detection and extraction. Furthermore, a local-quality-based blending procedure is also proposed. The accuracy of the zone-detection algorithm is comparable to an earlier work, yielding a mean-squared error of 25.9 and structural similarity of 95.8% (compared to a ground-truth estimate). Blending the surface and internal fingerprints improved the National Institute of Science and Technology's Fingerprint Image Quality scores and the average maximum match scores (when matched against conventional surface counterparts). The fingerprint blending procedure was able to combine high-quality regions from both fingerprints, thus mitigating surface wrinkles and anomalous poor-quality regions. Furthermore, spoof detection via a surface-to-internal fingerprint comparison was proposed and tested.

Anaerobic digestion of autoclaved and untreated food waste

International Nuclear Information System (INIS)

Tampio, Elina; Ervasti, Satu; Paavola, Teija; Heaven, Sonia; Banks, Charles; Rintala, Jukka

2014-01-01

Highlights: • Autoclaving decreased the formation of NH4-N and H 2 S during food waste digestion. • Stable digestion was achieved with untreated and autoclaved FW at OLR 6 kg VS/m 3 day. • Use of acclimated inoculum allowed very rapid increases in OLR. • Highest CH 4 yields were observed at OLR 3 kg VS/m 3 day with untreated FW. • Autoclaved FW produced highest CH 4 yields during OLR 4 kgVS/m 3 day. - Abstract: Anaerobic digestion of autoclaved (160 °C, 6.2 bar) and untreated source segregated food waste (FW) was compared over 473 days in semi-continuously fed mesophilic reactors with trace elements supplementation, at organic loading rates (OLRs) of 2, 3, 4 and 6 kg volatile solids (VS)/m 3 d. Methane yields at all OLR were 5–10% higher for untreated FW (maximum 0.483 ± 0.013 m 3 CH 4 /kg VS at 3 kg VS/m 3 d) than autoclaved FW (maximum 0.439 ± 0.020 m 3 CH 4 /kg VS at 4 kg VS/m 3 d). The residual methane potential of both digestates at all OLRs was less than 0.110 m 3 CH 4 /kg VS, indicating efficient methanation in all cases. Use of acclimated inoculum allowed very rapid increases in OLR. Reactors fed on autoclaved FW showed lower ammonium and hydrogen sulphide concentrations, probably due to reduced protein hydrolysis as a result of formation of Maillard compounds. In the current study this reduced biodegradability appears to outweigh any benefit due to thermal hydrolysis of ligno-cellulosic components

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.

Embrittlement of the alloy U 7.5 Nb 2.5 Zr by gaseous oxygen and hydrogen

International Nuclear Information System (INIS)

Lepoutre, D.; Nomine, A.M.; Miannay, D.

1981-04-01

Embrittlement of the alloy uranium 7.5 niobium 2.5 zirconium in gaseous oxygen and hydrogen versus stress intensity, temperature and pressure is studied using rupture mechanics. Cracking speed is determined. In oxygen, only cracks are produced and embrittlement is due to oxidation. In hydrogen at high pressure an hydride is formed and at low pressure cracks are produced but the mechanism is not identified [fr

Experimental investigation of particulate emissions from a diesel engine fueled with ultralow-sulfur diesel fuel blended with diglyme

Science.gov (United States)

Di, Yage; Cheung, C. S.; Huang, Zuohua

2010-01-01

Experiments are conducted on a 4-cylinder direct-injection diesel engine using ultralow-sulfur diesel as the base fuel and diglyme as the oxygenate component to investigate the particulate emissions of the engine under five engine loads at two engine speeds of 1800 rev min -1 and 2400 rev min -1. Blended fuels containing 5%, 10.1%, 15.2%, 20.4%, 25.7% and 53% by volume of diglyme, corresponding to 2%, 4%, 6%, 8%, 10% and 20% by mass of oxygen, are studied. The study shows that with the increase of oxygen in the fuel blends, smoke opacity, particulate mass concentration, NO x concentration and brake specific particulate emission are reduced at the two engine speeds. However, the proportion of soluble organic fraction is increased. For each blended fuel, the total particle number concentration is higher while the geometric mean diameter is smaller, compared with that of ultralow-sulfur diesel, though the particle number decreases with the oxygen content of the blended fuel. Furthermore, the blended fuels also increase the number concentrations of particles smaller than 100 nm.

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

Mixture Design Applied to the Development of Chickpea-Based Gluten-Free Bread with Attractive Technological, Sensory, and Nutritional Quality.

Science.gov (United States)

Santos, Fernanda G; Fratelli, Camilly; Muniz, Denise G; Capriles, Vanessa D

2018-01-01

The aim of the study was utilized chickpea to create appealing, nutritious, and palatable gluten-free bread (GFB). The performance of chickpea flour (CF) in single and composite GFB formulations was studied with a mixture design and response surface methodology. Six simplex-centroid designs for 3 ingredients were used to identify the ideal proportions of CF in various blends with cassava starch (CS), maize starch (MS), potato starch (PS), and rice flour (RF) achieving the best physical properties. For each design, 3 single, 3 binary, and 3 ternary formulations were prepared. The results showed that CF alone is suitable for bread production, resulting in GFB with higher volume and crumb firmness and lower crumb moisture than single formulations of other raw materials. However, the interactions between CF and PS or CS enhanced the loaf volume and decreased the crumb firmness values. The GFB prepared with only CF was accepted (overall acceptability score of 7.1- on a 10-cm scale). Nevertheless, the composite formulations prepared with CF75:PS25 or CF75:CS25 (flour basis) received overall acceptability scores of 8.2, like those of their white GFB, prepared with RF50:PS50 blend (flour basis), and wheat bread counterparts, used as positive controls. Compared to white GFB, both composite formulations presented nearly a twofold increase in ash and protein contents and a threefold increase in total fiber content. These results show that blends of CF75:PS25 or CF75:CS25 can be used to develop GFB with a good physical and sensory properties, as well as an enhanced nutritional composition. Gluten-free bread (GFB) made with 75% chickpea flour (CF) blend with 25% potato or cassava starch showed improved total minerals, protein and dietary fiber content and bread quality characteristics. Therefore, CF is a valuable ingredient for food technologists in manufacturing better-tasting and healthy GFB, which is important for consumers with gluten-related disorders since GFB often lack

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.

Examining the Impact of Video Feedback on Instructor Social Presence in Blended Courses

Directory of Open Access Journals (Sweden)

Jered Borup

2014-07-01

Full Text Available This mixed method research examined instructors’ use of video feedback and its impact on instructor social presence in 12 blended sections of three preservice educational technology courses. An independent samples t-test was conducted and found no significant difference in perceptions of instructor social presence between students who received video feedback (M = 5.77, SD = 0.85 and those who received text (M = 5.62, SD = 0.75; t(178 = 1.23, p = 0.22. The analysis of 22 student and nine teacher interviews found that participants generally viewed video feedback to be more effective at establishing instructor social presence because instructors could better speak with emotions, talk in a conversational manner, and create a sense of closeness with students. Students also explained that the blended learning format lessened the impact of video feedback on instructor social presence, which may help to explain why statistical differences were not found.

A novel fortified blended flour, corn-soy blend “plus-plus,” is not inferior to lipid-based ready-to-use supplementary foods for the treatment of moderate acute malnutrition in Malawian children12345

Science.gov (United States)

LaGrone, Lacey N; Trehan, Indi; Meuli, Gus J; Wang, Richard J; Thakwalakwa, Chrissie; Maleta, Kenneth; Manary, Mark J

2012-01-01

Background: Children with moderate acute malnutrition (MAM) are often treated with fortified blended flours, most commonly a corn-soy blend (CSB). However, recovery rates remain 5% worse than that achieved with either RUSF. Design: We conducted a prospective, randomized, investigator-blinded, controlled noninferiority trial involving rural Malawian children aged 6–59 mo with MAM. Children received 75 kcal CSB++ · kg−1 · d−1, locally produced soy RUSF, or an imported soy/whey RUSF for ≤12 wk. Results: The recovery rate for CSB++ (n = 763 of 888; 85.9%) was similar to that for soy RUSF (795 of 806, 87.7%; risk difference: −1.82%; 95% CI: −4.95%, 1.30%) and soy/whey RUSF (807 of 918, 87.9%; risk difference: −1.99%; 95% CI: −5.10%, 1.13%). On average, children who received CSB++ required 2 d longer to recover, and the rate of weight gain was less than that with either RUSF, although height gain was the same among all 3 foods studied. Conclusions: A novel, locally produced, fortified blended flour (CSB++) was not inferior to a locally produced soy RUSF and an imported soy/whey RUSF in facilitating recovery from MAM. The recovery rate observed for CSB++ was higher than that for any other fortified blended flour tested previously. This trial is registered at clinicaltrials.gov as NCT00998517. PMID:22170366

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.

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...

Physico-mechanical and structural properties of eggshell membrane gelatin- chitosan blend edible films

DEFF Research Database (Denmark)

Mohammadi, Reza; Mohammadifar, Mohammad Amin; Rouhi, Milad

2018-01-01

This study investigated the physico-mechanical and structural properties of composite edible films based on eggshell membrane gelatin (G) and chitosan (Ch) (75G:25Ch, 50G:50Ch, 25G:75Ch). The results demonstrated that the addition of Ch increased elongation at break significantly (p< 0.05), but r......This study investigated the physico-mechanical and structural properties of composite edible films based on eggshell membrane gelatin (G) and chitosan (Ch) (75G:25Ch, 50G:50Ch, 25G:75Ch). The results demonstrated that the addition of Ch increased elongation at break significantly (p... interactions introduced by the addition of chitosan to eggshell membrane gelatin as new resources could improve the films’ functional properties....

Mechanical behavior of Fe{sub 75}Mo{sub 5}P{sub 10}C{sub 7.5}B{sub 2.5} bulk-metallic glass under torsional loading

Energy Technology Data Exchange (ETDEWEB)

Zhang Xinjian [School of Chemical Engineering and Technology, Tianjin University, 92 Weijin Road, Tianjin 300072 (China); Huang Lu [Department of Materials Science and Engineering, University of Tennessee, TN 37996 (United States); Key Laboratory of Aerospace Materials and Performance (Ministry of Education), School of Materials Science and Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China); Chen Xu, E-mail: xchen@tju.edu.cn [School of Chemical Engineering and Technology, Tianjin University, 92 Weijin Road, Tianjin 300072 (China); Liaw, Peter K. [Department of Materials Science and Engineering, University of Tennessee, TN 37996 (United States); An Ke [Neutron Scattering Sciences Division, Oak Ridge National Laboratory, TN 37831 (United States); Zhang Tao [Key Laboratory of Aerospace Materials and Performance (Ministry of Education), School of Materials Science and Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China); Wang Gongyao [Department of Materials Science and Engineering, University of Tennessee, TN 37996 (United States)

2010-11-15

Research highlights: {yields} Fe{sub 75}Mo{sub 5}P{sub 10}C{sub 7.5}B{sub 2.5} bulk-metallic glass exhibits a brittle characteristic under torsional loading. {yields} The BMG occurs in a tensile mode failure under torsional loading. {yields} A slight cyclic-hardening behavior was observed in the initial loading cycles during torsional-fatigue tests. {yields} The torsional fatigue-fracture surface consists of three main regions. - Abstract: Pure- and cyclic-torsional studies were conducted on a Fe{sub 75}Mo{sub 5}P{sub 10}C{sub 7.5}B{sub 2.5} (atomic percent, at.%) bulk-metallic glass at room temperature for an understanding of its damage and fracture mechanisms. Under pure-torsional loading, the metallic glass exhibited very little plastic strain before fracture. The fracture initiated along the maximum tensile-stress plane, which is about 45{sup o} to the axial direction. The shear-fracture strength ({approx}510 MPa) is much lower than the compressive-fracture strength ({approx}3280 MPa), which suggests that different deformation mechanisms be present under various loading modes. Instead of an apparent vein-type structure, the fracture morphologies revealed a crack-initiation site, a mirror region, a mist region, and a hackle region. Under cyclic-torsional loading, fatigue cracks initiated from casting defects, and propagate generally along the maximum tensile-stress plane. A slight cyclic-hardening behavior was observed in initial loading steps. The fatigue-fracture surface consists of three main regions: the fatigue crack-initiation, crack-propagation, and final-fast-fracture areas. The striations resulting from the blunting and re-sharpening of the fatigue crack tip were observed in the crack-propagation region. Based on these results, the damage and fracture mechanisms of the metallic glass induced by torsional loadings are elucidated.

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.

Superconducting nanowire single photon detectors fabricated from an amorphous Mo{sub 0.75}Ge{sub 0.25} thin film

Energy Technology Data Exchange (ETDEWEB)

Verma, V. B.; Lita, A. E.; Vissers, M. R.; Marsili, F.; Pappas, D. P.; Mirin, R. P.; Nam, S. W. [National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305 (United States)

2014-07-14

We present the characteristics of superconducting nanowire single photon detectors (SNSPDs) fabricated from amorphous Mo{sub 0.75}Ge{sub 0.25} thin-films. Fabricated devices show a saturation of the internal detection efficiency at temperatures below 1 K, with system dark count rates below 500 cps. Operation in a closed-cycle cryocooler at 2.5 K is possible with system detection efficiencies exceeding 20% for SNSPDs which have not been optimized for high detection efficiency. Jitter is observed to vary between 69 ps at 250 mK and 187 ps at 2.5 K using room temperature amplifiers.

Water Susceptibility and Mechanical Properties of Thermoplastic Starch–Pectin Blends Reactively Extruded with Edible Citric Acid

OpenAIRE

Da Róz,Alessandra Luzia; Veiga-Santos,Pricila; Ferreira,Adriane Medeiros; Antunes,Thaís Cristina Ribeiro; Leite,Fabio de Lima; Yamaji,Fabio Minoru; Carvalho,Antonio José Felix de

2016-01-01

Pectin and starch are edible, non-toxic, biodegradable and obtained from renewable sources. Also, have the benefit to be easily cross-linked producing hydrogels. Reactive extrusion with edible citric acid and cross linking interactions was evaluated on extruded thermoplastic in natura and cationic starch-pectin blends. Materials water susceptibility and mechanical properties were characterised. Reactive extrusion decreased (up to 75% in natura starch) mechanical properties. Also have decrease...

Production and characterization of thermoplastic cassava starch, functionalized poly(lactic acid), and their reactive compatibilized blends

Science.gov (United States)

Detyothin, Sukeewan

Cassava starch was blended with glycerol using a co-rotating twin-screw extruder (TSE). Thermoplastic cassava starch (TPCS) at a ratio of 70/30 by weight of cassava/glycerol was selected and further blended with other polymers. TPCS sheets made from compression molding had low tensile strength (0.45 +/- 0.05 MPa) and Young's modulus (1.24 +/- 0.58 MPa), but moderate elongation at break (83.0 +/- 0.18.6%), medium level of oxygen permeability, and high water vapor permeability with a very high rate of water absorption. TPCS was blended with poly(lactic acid) (PLA) at various ratios by using a TSE. The blend resins exhibited good properties such as increased thermal stability (Tmax) and crystallinity of PLA, and improved water sensitivity and processability of TPCS. PLA and TPCS exhibited a high interfacial tension between the two phases of 7.9 mJ·m -2, indicating the formation of an incompatible, immiscible blend. SEM micrographs showed a non-homogeneous distribution of TPCS droplets in the PLA continuous phase. TEM micrographs of the blend films made by cast-film extrusion showed coalescence of the TPCS droplets in the PLA continuous phase of the blend, indicating that the compatibility between the polymer pair needs to be improved. A response surface methodology (RSM) design was used to analyze the effects of maleic anhydride (MA) and 2,5-bis(tert-butylperoxy)-2,5-dimethylhexane (Luperox or L101) contents, and TSE screw speed on the degree of grafted MA and number average molecular weight (Mn) of functionalized PLA (PLA-g-MA), a reactive compatibilizer. PLA-g- MA made by reactive extrusion had an array of colors depending on the content of L101 and MA used. New FTIR peaks suggested that MA was grafted onto the PLA backbone and oligomeric MA may occur. Increasing L101 increased the degree of grafting and decreased Mn, but the Mn of the PLA-g-MA's produced with a high amount of L101 was stable during storage. MA exhibited an optimum concentration for maximizing the

Anaerobic digestion of autoclaved and untreated food waste

Energy Technology Data Exchange (ETDEWEB)

Tampio, Elina, E-mail: elina.tampio@mtt.fi [Bioenergy and Environment, MTT Agrifood Research Finland, FI-31600 Jokioinen (Finland); Ervasti, Satu; Paavola, Teija [Bioenergy and Environment, MTT Agrifood Research Finland, FI-31600 Jokioinen (Finland); Heaven, Sonia; Banks, Charles [University of Southampton, Faculty of Engineering and the Environment, Southampton SO17 1BJ (United Kingdom); Rintala, Jukka [Bioenergy and Environment, MTT Agrifood Research Finland, FI-31600 Jokioinen (Finland)

2014-02-15

Highlights: • Autoclaving decreased the formation of NH4-N and H{sub 2}S during food waste digestion. • Stable digestion was achieved with untreated and autoclaved FW at OLR 6 kg VS/m{sup 3}day. • Use of acclimated inoculum allowed very rapid increases in OLR. • Highest CH{sub 4} yields were observed at OLR 3 kg VS/m{sup 3}day with untreated FW. • Autoclaved FW produced highest CH{sub 4} yields during OLR 4 kgVS/m{sup 3}day. - Abstract: Anaerobic digestion of autoclaved (160 °C, 6.2 bar) and untreated source segregated food waste (FW) was compared over 473 days in semi-continuously fed mesophilic reactors with trace elements supplementation, at organic loading rates (OLRs) of 2, 3, 4 and 6 kg volatile solids (VS)/m{sup 3} d. Methane yields at all OLR were 5–10% higher for untreated FW (maximum 0.483 ± 0.013 m{sup 3} CH{sub 4}/kg VS at 3 kg VS/m{sup 3} d) than autoclaved FW (maximum 0.439 ± 0.020 m{sup 3} CH{sub 4}/kg VS at 4 kg VS/m{sup 3} d). The residual methane potential of both digestates at all OLRs was less than 0.110 m{sup 3} CH{sub 4}/kg VS, indicating efficient methanation in all cases. Use of acclimated inoculum allowed very rapid increases in OLR. Reactors fed on autoclaved FW showed lower ammonium and hydrogen sulphide concentrations, probably due to reduced protein hydrolysis as a result of formation of Maillard compounds. In the current study this reduced biodegradability appears to outweigh any benefit due to thermal hydrolysis of ligno-cellulosic components.

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…

Tramadol hydrochloride 75 mg/dexketoprofen 25 mg oral fixed-dose combination in moderate-to-severe acute pain: sustained analgesic effect over a 56-h period in the postoperative setting.

Science.gov (United States)

Montero Matamala, A; Bertolotti, M; Contini, M P; Guerrero Bayón, C; Nizzardo, A; Paredes Lario, I; Pizà Vallespir, B; Scartoni, S; Tonini, G; Capriati, A; Pellacani, A

2017-06-01

Multimodal analgesia constitutes a common strategy in pain management. A tramadol hydrochloride 75 mg/dexketoprofen 25 mg oral fixed combination (TRAM/DKP 75 mg/25 mg) has been recently registered and released in Europe for the treatment of moderate-to-severe acute pain. This paper provides additional analyses on the results of two phase III clinical trials (DEX-TRA-04 and DEX-TRA-05) on postoperative pain to document its sustained effect. The analysis was applied to a modified intention-to-treat population (mITT, n = 933) of patients undergoing active treatment from the first dose, to assess the sustained effect of TRAM/DKP 75 mg/25 mg on pain intensity (PI-VAS 0-100) over 56 h from first drug intake. The superior analgesic effect of TRAM/DKP 75 mg/25 mg over 56 h in terms of difference in PI-VAS (mean [SE]) was shown for DEX-TRA-04 (-11.0 [0.55] over dexketoprofen 25 mg and -9.1 [0.55] over tramadol 100 mg, P ≤ 0.0001) and for DEX-TRA-05 (-10.4 [0.51] over dexketoprofen 25 mg and -8.3 [0.51] over tramadol 100 mg, P ≤ 0.0001). The statistical analysis performed on data coming from both studies confirms the superior sustained analgesia of TRAM/DKP 75 mg/25 mg over tramadol 100 mg and dexketoprofen 25 mg. These results are consistent with the previously published data obtained on the ITT population and strongly support the role of this oral fixed-dose combination in the treatment of moderate-to-severe acute pain. Copyright 2017 Clarivate Analytics.

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.

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

Effects of commercial marinade seasoning and a natural blend of cultured sugar and vinegar on Campylobacter jejuni and Salmonella Typhimurium and the texture of chicken breasts.

Science.gov (United States)

Park, Na Yoon; Hong, Soo Hyeon; Yoon, Ki Sun

2014-03-01

Marination using various ingredients has been widely used to improve microbial safety and quality of chicken products at retail markets. The objective of this study was to investigate the effects of commercial marinade seasoning and cultured sugar/vinegar blend on Campylobacter jejuni and Salmonella Typhimurium populations during refrigerated storage. In addition, their effects on the texture of precooked chicken breasts during frozen and refrigerated storage was investigated. Chicken breasts inoculated with 4.5 to 5.0 log cfu/g of C. jejuni and Salmonella Typhimurium were treated with 3% cultured sugar/vinegar blend with and without 0.6% polish rub seasoning containing 32% herb content. Breasts were then vacuum-packaged and stored at 4 and 10°C. Survival and growth curves were fitted to the Baranyi equation to determine survival and growth kinetics of C. jejuni and Salmonella Typhimurium. In addition, the vacuum-packaged precooked chicken breasts with different marination treatments were subjected to 3 freeze-thaw cycles and shear force was measured. At 4°C, the populations of C. jejuni and Salmonella Typhimurium decreased, regardless of treatment group during storage. The greatest survival for C. jejuni was observed in untreated chicken breasts. At 10°C, the growth of Salmonella Typhimurium was completely prevented in precooked chicken breasts treated with 3% cultured sugar/vinegar blend, regardless of the presence of 0.6% seasoning. The 3% cultured sugar/vinegar blend also improved the tenderness of frozen chicken breasts and refrigerated, ready-to-eat chicken breast. Therefore, a natural blend of cultured sugar and vinegar can be used as antimicrobial and texture-modifying agents for poultry meat and poultry products.

Influence of Curing Age and Mix Composition on Compressive Strength of Volcanic Ash Blended Cement Laterized Concrete

Directory of Open Access Journals (Sweden)

Babafemi A.J.

2012-01-01

Full Text Available This study investigates the influence of curing age and mix proportions on the compressive strength of volcanic ash (VA blended cement laterized concrete. A total of 288 cubes of 100mm dimensions were cast and cured in water for 3, 7, 28, 56, 90 and 120 days of hydration with cement replacement by VA and sand replacement by laterite both ranging from 0 to 30% respectively while a control mix of 28-day target strength of 25N/mm2 (using British Method was adopted. The results show that the compressive strength of the VA-blended cement laterized concrete increased with the increase in curing age but decreased as the VA and laterite (LAT contents increased. The optimum replacement level was 20%LAT/20%VA. At this level the compressive strength increased with curing age at a decreasing rate beyond 28 days. The target compressive strength of 25N/mm2 was achieved for this mixture at 90 days of curing. VA content and curing age was noted to have significant effect (α ≤ 0.5 on the compressive strength of the VA-blended cement laterized concrete.

Calcination of Fluorinel-sodium waste blends using sugar as a feed additive (formerly WINCO-11879)

International Nuclear Information System (INIS)

Newby, B.J.; Thomson, T.D.; O'Brien, B.H.

1992-06-01

Methods were studied for using sugar as a feed additive for converting the sodium-bearing wastes stored at the Idaho Chemical Processing Plant into granular, free flowing solids by fluidized-bed calcination at 500 degrees C. All methods studied blended sodium-bearing wastes with Fluorinel wastes but differed in the types of sugar (sucrose or dextrose) that were added to the blend. The most promising sugar additive was determined to be sucrose, since it is converted more completely to inorganic carbon than is dextrose. The effect of the feed aluminum-to-alkali metal mole ratio on calcination of these blends with sugar was also investigated. Increasing the aluminum-to-alkali metal ratio from 0.6 to 1.0 decreased the calcine product-to-fines ratio from 3.0 to 1.0 and the attrition index from 80 to 15%. Further increasing the ratio to 1.25 had no effect

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)

Comparative study on experiments and simulation of blended cathode active materials for lithium ion batteries

International Nuclear Information System (INIS)

Appiah, Williams Agyei; Park, Joonam; Van Khue, Luu; Lee, Yunju; Choi, Jaecheol; Ryou, Myung-Hyun; Lee, Yong Min

2016-01-01

We simulate the electrochemical properties of Li-ion cells consisting of a blended cathode composed of LiMn 2 O 4 and LiNi 0.6 Co 0.2 Mn 0.2 O 2 and an artificial graphite anode using the Li-ion battery model available in COMSOL MULTIPHYSICS 4.4 along with a capacity fade model. The discharge profiles of the pure and blended cathodes at various current rates obtained through simulations and experimental results are well matched. By combining two capacity fade models available in literature, namely the solid electrolyte interphase (SEI) growth model and the Mn 2+ dissolution model, the cycling performance of the pure LiMn 2 O 4 cells at 25 °C are successfully simulated and found to be in a good agreement with the experimental results. The blended cathode exhibits better capacity retention than the pure LiMn 2 O 4 during cycling. We also observed that at high powers, the gravimetric energy density of the LiMn 2 O 4 cathode exceeds that of the LiNi 0.6 Co 0.2 Mn 0.2 O 2 cathode; the reverse effect is seen at low powers. Further, we were able to easily modulate the energy and power densities of the blended cathode system by changing the blend ratio in our simulation model.

Combustion characteristics of Malaysian oil palm biomass, sub-bituminous coal and their respective blends via thermogravimetric analysis (TGA).

Science.gov (United States)

Idris, Siti Shawalliah; Rahman, Norazah Abd; Ismail, Khudzir

2012-11-01

The combustion characteristics of Malaysia oil palm biomass (palm kernel shell (PKS), palm mesocarp fibre (PMF) and empty fruit bunches (EFB)), sub-bituminous coal (Mukah Balingian) and coal/biomass blends via thermogravimetric analysis (TGA) were investigated. Six weight ratios of coal/biomass blends were prepared and oxidised under dynamic conditions from temperature 25 to 1100°C at four heating rates. The thermogravimetric analysis demonstrated that the EFB and PKS evolved additional peak besides drying, devolatilisation and char oxidation steps during combustion. Ignition and burn out temperatures of blends were improved in comparison to coal. No interactions were observed between the coal and biomass during combustion. The apparent activation energy during this process was evaluated using iso-conversional model free kinetics which resulted in highest activation energy during combustion of PKS followed by PMF, EFB and MB coal. Blending oil palm biomass with coal reduces the apparent activation energy value. Copyright © 2012 Elsevier Ltd. All rights reserved.

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…

Flour mill stream blending affects sugar snap cookie and Japanese sponge cake quality and oxidative cross-linking potential of soft white wheat.

Science.gov (United States)

The purpose of this research was to study the functional differences between straight grade (75% extraction rate) and patent (60% extraction rate) flour blends from 28 genetically pure soft white and club wheat grain lots, as evidenced by variation in sugar snap cookie and Japanese sponge cake quali...

Effects of aniline concentrations on the electrical and mechanical properties of polyaniline polyvinyl alcohol blends

Directory of Open Access Journals (Sweden)

J. Bhadra

2017-07-01

Full Text Available In this work, we present an exclusive study on the effect of the feeding ratio of the monomer (aniline on the structural, thermal, mechanical and electrical properties of polyaniline (PANI polyvinyl alcohol (PVA blends. The films obtained from the blends are characterised to determine their surface properties and structural morphology (elemental analysis, SEM and FTIR, thermal properties (TGA and DSC and optical properties (UV–Vis spectroscopy. We study the effects of aniline on the mechanical and electrical properties of the composites by performing tensile, four probe and A.C. conductivity measurements, respectively. The SEM images reveal a heterogeneous distribution of conductive PANI particles in the continuous PVA matrix. During this experiment, the tensile strength of the blend films is maintained with an increase in the amount of aniline (up to 25 wt%, and this behaviour is attributed to intermolecular hydrogen bonding between PANI and PVA in the presence of the surfactant DBSA. The potential attraction of the experiment lies in the nature of the conductivity (of the blend films, which is found to increase from 10−8 to 10−3 S/cm with a percolation threshold of 0.78 wt%.

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…

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.

NESDIS Blended Rain Rate (RR) Products

Data.gov (United States)

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

Impact of ancient cereals, pseudocereals and legumes on starch hydrolysis and antiradical activity of technologically viable blended breads.

Science.gov (United States)

Collar, Concha; Jiménez, Teresa; Conte, Paola; Fadda, Costantino

2014-11-26

Wheat flour replacement from 22.5% up to 45% by incorporation of ternary blends of teff (T), green pea (GP) and buckwheat (BW) flours provided technologically viable and acceptable sensory rated multigrain breads with superior nutritional value compared to the 100% wheat flour (WT) counterparts. Blended breads exhibited superior nutritional composition, larger amounts of bioaccessible polyphenols, higher anti-radical activity, and lower and slower starch digestibility. Simultaneous lower rapidly digestible starch (57.1%) and higher slowly digestible starch (12.9%) and resistant starch (2.8%) contents (g per 100g fresh bread), considered suitable nutritional trends for dietary starch fractions, were met by the blend formulated 7.5% T, 15% GP, 15% BK. The associated mixture that replaced 37.5% WT, showed a rather lower extent and slower rate of starch hydrolysis with medium-low values for C∞, and H90, and lowest k, and intermediate expected Glycaemic Index (86). All multigrain breads can be labelled as source of dietary fibre (≥ 3 g dietary fibre/100g bread). Copyright © 2014 Elsevier Ltd. All rights reserved.

Structural parameters and resistive switching phenomenon study on Cd0.25Co0.75Fe2O4 ferrite thin film

International Nuclear Information System (INIS)

Chhaya, U.V.; Gadhvi, M.R.; Mistry, B.V.; Bhavsar, K.H.; Joshi, U.S.; Lakhani, V.K.; Modi, K.B.

2011-01-01

Cadmium substituted cobalt ferrite thin film with nominal composition Cd 0.25 Co 0.75 Fe 2 O 4 , has been grown on quartz substrate by chemical solution deposition and their structural and electrical properties have been investigated. Grazing incidence X-ray diffraction (XRD) confirmed single phase spine) structure with nanometer grain size. Atomic force microscopic analysis revealed uniform nano structured growth of about 70 nm average crystallite size. The XRD data have been used to determine the distribution of cations among the tetrahedral and octahedral sites of the spinel lattice and various structural parameters. The cation distribution determined from X-ray diffraction line intensity calculations revealed, 60% octahedral sites occupancy of Cd 2+ -ions in the composition. Four terminal I-V measurements show hysteretic curves, suggesting high resistance state (HRS) and low resistance state (LRS) in the film with polarity dependence. Maximum resistance ratio, R high /R low of 57% was observed at room temperature in the Ag/Cd 0.25 Co 0.75 Fe 2 O 4 /Ag planar structure. Observed resistance switching is attributed to combined effects, viz., in the LRS, the major fraction of cadmium occupation and electron exchange between Fe 3+ and Fe 2+ at the B-sites, whereas the HRS shows Schottky-like conduction mechanism at the Ag/Cd 0.25 Co 0.75 Fe 2 O 4 interface. (author)

Solids precipitation in crude oils, gas-to-liquids and their blends

Science.gov (United States)

Ramanathan, Karthik

thermodynamic model based on a modified regular solution theory. A study was done to test the sensitivity of the thermodynamic model to varying levels of crude oil characterization input data for a fourth crude oil sample. The differentiation of the solute fraction (C25+) into the normal alkane, non-n-alkane and the aromatic fractions was found to be important for improving the predictive accuracy of the model. The n-alkane and non-n-alkane distribution used in the modeling of wax precipitation for the three crude oils blended with the GTL liquid gave the WPT's that agreed to within 5% of the experimental values. The precipitated solid amounts were overestimated using this method.

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.

The crystal structure of (Nb$_{0.75}$Cu$_{0.25}$)Sn$_{2}$ in the Cu-Nb-Sn system

CERN Document Server

Martin, Stefan; Nolze, Gert; Leineweber, Andreas; Leaux, Floriane; Scheuerlein, Christian

2017-01-01

During the processing of superconducting Nb$_{3}$Sn wire, several intermediate intermetallic phases including a previously encountered Cu-Nb-Sn phase show up. The yet unknown crystal structure of this phase is now identified by a combination of different experimental techniques and database search to be of the hexagonal NiMg2 type with a proposed composition of about (Nb0.75Cu0.25)Sn2. The structure determination started from an evaluation of the lattice parameters from EBSD Kikuchi patterns from quenched material suggesting hexagonal or orthorhombic symmetry. A database search then led to the hexagonal NiMg2 type structure, the presence of which was confirmed by a Rietveld analysis on the basis of high energy synchrotron X-ray powder diffraction data. Assuming a partial substitution of Nb in orthorhombic NbSn2 by Cu, the change of the valence electron concentration provokes a structural transformation from the CuMg2 type for NbSn2 to the NiMg2 type for (Nb0.75Cu0.25)Sn2. In the previous literature the (Nb0.7...

Semi-field assessment of the BG-Malaria trap for monitoring the African malaria vector, Anopheles arabiensis.

Directory of Open Access Journals (Sweden)

Elis P A Batista

Full Text Available Odour-baited technologies are increasingly considered for effective monitoring of mosquito populations and for the evaluation of vector control interventions. The BG-Malaria trap (BGM, which is an upside-down variant of the widely used BG-Sentinel trap (BGS, has been demonstrated to be effective to sample the Brazilian malaria vector, Anopheles darlingi. We evaluated the BGM as an improved method for sampling the African malaria vectors, Anopheles arabiensis. Experiments were conducted inside a large semi-field cage to compare trapping efficiencies of BGM and BGS traps, both baited with the synthetic attractant, Ifakara blend, supplemented with CO2. We then compared BGMs baited with either of four synthetic mosquito lures, Ifakara blend, Mbita blend, BG-lure or CO2, and an unbaited BGM. Lastly, we compared BGMs baited with the Ifakara blend dispensed via either nylon strips, BG cartridges (attractant-infused microcapsules encased in cylindrical plastic cartridge or BG sachets (attractant-infused microcapsules encased in plastic sachets. All tests were conducted between 6P.M. and 7A.M., with 200-600 laboratory-reared An. arabiensis released nightly in the test chamber. The median number of An. arabiensis caught by the BGM per night was 83, IQR:(73.5-97.75, demonstrating clear superiority over BGS (median catch = 32.5 (25.25-37.5. Compared to unbaited controls, BGMs baited with Mbita blend caught most mosquitoes (45 (29.5-70.25, followed by BGMs baited with CO2 (42.5 (27.5-64, Ifakara blend (31 (9.25-41.25 and BG lure (16 (4-22. BGM caught 51 (29.5-72.25 mosquitoes/night, when the attractants were dispensed using BG-Cartridges, compared to BG-Sachet (29.5 (24.75-40.5, and nylon strips (27 (19.25-38.25, in all cases being significantly superior to unbaited controls (p < 000.1. The findings demonstrate potential of the BGM as a sampling tool for African malaria vectors over the standard BGS trap. Its efficacy can be optimized by selecting

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.

Impact of field dodder (Cuscuta campestris Yunk. on physiological and anatomical changes in untreated and herbicide-treated alfalfa plants

Directory of Open Access Journals (Sweden)

Sarić-Krsmanović Marija

2016-01-01

Full Text Available The effects of field dodder on physiological processes and the anatomy of alfalfa plants were examined under controlled conditions. The experiment included the following variants: N - noninfested alfalfa plants (control; I - infested alfalfa plants (untreated; T - infested plants treated with imazethapyr. Imazethapyr application rate was 100 g a.i. ha-1. The following parameters were checked: physiological - pigment content (chlorophyll ɑ, chlorophyll b, total carotenoids; anatomical - stem parameters: thickness of epidermis and cortex, and diameter of stem and central cylinder; leaf parameters: thickness of epidermis, parenchyma and spongy tissue, mesophyll and underside leaf epidermis, and diameter of bundle sheath cells in alfalfa plants. Pigment contents and anatomical parameters were measured: prior to herbicide treatment (0 assessment, then 7 (I assessment, 14 (II assessment, 21 (III assessment, 28 (IV assessment and 35 (V assessment days after application (DAA. Field dodder was found to affect the contents of chlorophyll ɑ, chlorophyll ɑ and carotenoids in untreated alfalfa plants, causing significant reductions in pigment content. Conversely, percent reduction in the treated plants decreased 22-5% for chlorophyll ɑ, 25-1%, for chlorophyll b, and 21-11% for carotenoids, while a stimulating effect of 1-6% was observed for the contents of chlorophyll b and carotenoids 35 DAA. Plants infested (untreated by field dodder had lower values of most anatomical parameters, compared to noninfested plants. The measured anatomical parameters of alfalfa stems and leaves had significantly higher values in noninfested plants and plants treated with imazethapyr than in untreated plants.

Effect of Clopidogrel on Platelet CD Markers in Normal Individuals and in Patients with Untreated Type 2 Diabetes Mellitus

International Nuclear Information System (INIS)

Saboor, M.; Moinuddin, M.; Ilyas, S.

2015-01-01

The objective of this study was to evaluate the effect of clopidogrel response in patients with untreated type 2 diabetes mellitus as compared with normal individuals. One hundred and seven subjects i.e. 32 normal and 75 patients with untreated type 2 diabetes mellitus were enrolled in this study. In the first step, normal subjects as well as diabetic patients were selected and tested for various laboratory parameters and platelets flow cytometry. In the second step, an antiplatelet drug (clopidogrel) was administered for 10 days to each individual enrolled in the study. After 10 days blood samples were collected for platelets flow cytometry. CD41 and CD61 did not show any change after the administration of clopidogrel in resting and activated platelets. CD63 and CD62p positivity was increased in normal and in diabetic patients' platelets after activation with ADP before clopidogrel. It was decreased in normal resting and ADP stimulated platelets after clopidogrel treatment. CD63 and CD62p positivity in resting and ADP stimulated patients platelets was also decreased after clopidogrel treatment. The change was, however, not as marked as in normal subjects. (author)

Thermal release of {sup 3}He from tritium aged LaNi{sub 4.25}Al{sub 0.75} hydride

Energy Technology Data Exchange (ETDEWEB)

Staack, G.C.; Crowder, M.L.; Klein, J.E. [Savannah River National Laboratory, Aiken, SC (United States)

2015-03-15

The Savannah River Site Tritium Facilities (SRS-TF) utilizes LANA.75 (LaNi{sub 4.25}Al{sub 0.75})in the tritium process to store hydrogen isotopes. The vast majority of {sup 3}He born from the radioactive decay of tritium stored in LANA.75 is trapped in the hydride metal matrix. The SRS-TF has multiple LANA.75 tritium storage beds that have been retired from service with significant quantities of He-3 trapped in the metal. To support He-3 recovery, the Savannah River National Laboratory (SRNL) conducted thermogravimetric analysis coupled with mass spectrometry (TGA-MS) on a tritium aged LANA.75 sample. TGA-MS testing was performed in an argon environment. Prior to testing, the sample was isotopically exchanged with deuterium to reduce residual tritium and passivated with air to alleviate pyrophoric concerns associated with handling the material outside of an inert glovebox. Analyses indicated that gas release from this sample was bimodal, with peaks near 220 and 490 C. degrees. The first peak consisted of both {sup 3}He and residual hydrogen isotopes, the second was primarily {sup 3}He. The bulk of the gas was released by 600 Celsius degrees. (author)

Interesterification of engkabang (Shorea macrophylla) fat--canola oil blend with lipase from Candida antarctica to simulate the properties of lard.

Science.gov (United States)

Illiyin, Mohamed Roslan Nur; Marikkar, Jalaldeen Mohamed Nazrim; Loke, Mei Key; Shuhaimi, Musthafa; Mahiran, Basri; Miskandar, Mat Saari

2014-01-01

A study was carried out to compare the composition and thermal properties of lard (LD) and engkabang fat (EF) - canola oil (CaO) blend interesterified with Candida antartica lipase (C. antartica). A fat blend EF-4 (40% EF in CaO) was prepared and interesterified using C. antartica lipase at 60°C for different time intervals (6 h, 12 h and 24 h) with 200 rpm agitation. The fat blends before and after interesterification were compared to LD with respect to their slip melting points (SMP), fatty acid and triacyglycerol (TAG) compositions, melting, solidification and polymorphic properties. Result showed that the slip melting point (SMP) of the fat blend interesterified for 6 h was the closest to that of LD. The solid fat content (SFC) values of fat blends interesterified for 12 and 24 h were found to become equal to those of LD within the temperature range of 0 to 20°C. In addition, all three interesterified blends had SFC values similar to those of LD within the temperature range of 30-40°C. According to thermal analysis, the transition of the fat blend interesterified for 24 h appearing at -2.39°C was similar to the low melting thermal transition of LD and the transition of the fat blend interesterified for 12 h appearing at 26.25°C was similar to the high melting thermal transition of LD. However, there is no compatibility between LD and all three interesterified blends with regard to polymorphic behaviour.

Effect of the antiestrogen ethamoxytriphetol (MER-25) on placental low density lipoprotein uptake and degradation in baboons

International Nuclear Information System (INIS)

Henson, M.C.; Babischkin, J.S.; Pepe, G.J.; Albrecht, E.D.

1988-01-01

The present study determined if the decline in placental progesterone (P4) production that results from administration of the antiestrogen ethamoxytriphetol (MER-25) to pregnant baboons results from a change in placental low density lipoprotein (LDL) uptake and/or degradation. Pregnant baboons (Papio anubis) were untreated (n = 10) or received MER-25 (25 mg/kg BW, orally; n = 10) daily on days 140-170 of gestation (term, 184 days). Placentas were removed by cesarean section on day 170 of gestation, and villous tissue was dispersed with 0.1% collagenase at 37 C for 40 min. Placental cells (10(6)) were incubated in medium 199 (pH 7.2) for 12 h at 37 C with increasing amounts (5-100 micrograms) of [125I]LDL, with or without a 100-fold excess of unlabeled baboon LDL. Mean (+/- SE) peripheral serum P4 concentrations on days 140-170 of gestation were 51% lower (P less than 0.01) in MER-25-treated (5.7 +/- 0.3 ng/ml) than in untreated (11.6 +/- 0.5 ng/ml) baboons. The uptake of LDL was 56% lower (P less than 0.01) in placental cells from antiestrogen-treated (6.3 +/- 1.6 ng/micrograms cell protein) than in those from untreated (14.4 +/- 1.9 ng/micrograms cell protein) baboons. The dissociation constants for placental LDL uptake, as assessed by Scatchard analysis, however, were similar in untreated (0.80 microgram/ml) and MER-25-treated (0.76 microgram/ml) animals. The amount of [125I]LDL concomitantly degraded by cells from baboons that received MER-25 was 54% of that degraded by cells from untreated controls. The relative decline in LDL degradation by cells of antiestrogen-treated baboons was proportionate to the decline in overall LDL uptake. The results indicate, therefore, that antiestrogen treatment decreased the amount of placental LDL uptake, but did not change the affinity for the lipoprotein

Effect of the antiestrogen ethamoxytriphetol (MER-25) on placental low density lipoprotein uptake and degradation in baboons

Energy Technology Data Exchange (ETDEWEB)

Henson, M.C.; Babischkin, J.S.; Pepe, G.J.; Albrecht, E.D.

1988-05-01

The present study determined if the decline in placental progesterone (P4) production that results from administration of the antiestrogen ethamoxytriphetol (MER-25) to pregnant baboons results from a change in placental low density lipoprotein (LDL) uptake and/or degradation. Pregnant baboons (Papio anubis) were untreated (n = 10) or received MER-25 (25 mg/kg BW, orally; n = 10) daily on days 140-170 of gestation (term, 184 days). Placentas were removed by cesarean section on day 170 of gestation, and villous tissue was dispersed with 0.1% collagenase at 37 C for 40 min. Placental cells (10(6)) were incubated in medium 199 (pH 7.2) for 12 h at 37 C with increasing amounts (5-100 micrograms) of (125I)LDL, with or without a 100-fold excess of unlabeled baboon LDL. Mean (+/- SE) peripheral serum P4 concentrations on days 140-170 of gestation were 51% lower (P less than 0.01) in MER-25-treated (5.7 +/- 0.3 ng/ml) than in untreated (11.6 +/- 0.5 ng/ml) baboons. The uptake of LDL was 56% lower (P less than 0.01) in placental cells from antiestrogen-treated (6.3 +/- 1.6 ng/micrograms cell protein) than in those from untreated (14.4 +/- 1.9 ng/micrograms cell protein) baboons. The dissociation constants for placental LDL uptake, as assessed by Scatchard analysis, however, were similar in untreated (0.80 microgram/ml) and MER-25-treated (0.76 microgram/ml) animals. The amount of (125I)LDL concomitantly degraded by cells from baboons that received MER-25 was 54% of that degraded by cells from untreated controls. The relative decline in LDL degradation by cells of antiestrogen-treated baboons was proportionate to the decline in overall LDL uptake. The results indicate, therefore, that antiestrogen treatment decreased the amount of placental LDL uptake, but did not change the affinity for the lipoprotein.

[(Nitrato-κ2O,O′(nitrito-κ2O,O′(0.25/1.75]bis(1,10-phenanthroline-κ2N,N′cadmium(II

Directory of Open Access Journals (Sweden)

Ezzatollah Najafi

2011-02-01

Full Text Available The reaction of cadmium nitrate and sodium nitrite in the presence of 1,10-phenanthroline yields the mixed nitrate–nitrite title complex, [Cd(NO21.75(NO30.25(C12H8N22]. The metal ion is bis-chelated by two N-heterocycles as well as by the nitrate/nitrite ions in a distorted dodecahedral CdN4O4 coordination environment. One nitrite group is ordered; the other is disordered with respect to a nitrate group (ratio 0.75:0.25 concerning the O atom that is not involved in bonding to the metal ion.

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…

Quantification of the Robusta fraction in a coffee blend via Raman spectroscopy: proof of principle.

Science.gov (United States)

Wermelinger, Thomas; D'Ambrosio, Lucio; Klopprogge, Babette; Yeretzian, Chahan

2011-09-14

Among the 100 different known Coffea species, Coffea arabica L. (Arabica) and Coffea canephora Pierre (Robusta) are the only two of commercial interest. They differ in a range of agronomic, genetic, and chemical properties. Due to the significant price difference between Arabica and Robusta, there is an economic incentive to illicitly replace Arabica with Robusta. Therefore, it is crucial to have accurate methods to determine the Robusta-to-Arabica-ratio in blends. This paper presents the proof of principle of a new and fast approach to determine the Robusta fraction in a blend based on Raman spectroscopy. The oils of two references (a pure Robusta and pure Arabica coffee) and six blends thereof consisting of different Robusta and Arabica fractions were extracted using a Soxhlet system. The solutes were analyzed by means of Raman spectroscopy without further workup. Using the intensity ratio between two Raman peaks, one characteristic for kahweol and one characteristic for fatty acids, allowed determinination of the Robusta content in a given mixture. The intensity ratio is linearly dependent on the Robusta content of the compound. Above a Robusta content of 75 wt %, kahweol was not detectable. The Raman data are in agreement with results obtained from the very time-consuming multistep DIN 10777 procedures based on HPLC.

7 CFR 319.56-44 - Untreated grapefruit, sweet oranges, and tangerines from Mexico for processing.

Science.gov (United States)

2010-01-01

... 7 Agriculture 5 2010-01-01 2010-01-01 false Untreated grapefruit, sweet oranges, and tangerines... QUARANTINE NOTICES Fruits and Vegetables § 319.56-44 Untreated grapefruit, sweet oranges, and tangerines from Mexico for processing. Untreated grapefruit (Citrus paradisi), sweet oranges (Citrus sinensis), and...

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)

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.

Bone scintigraphy and radiology in untreated Paget's disease

International Nuclear Information System (INIS)

Vellenga, C.J.L.R.; Pauwels, E.K.J.; Bijvost, O.L.M.

1985-01-01

This study is based on 107 patients with untreated Paget's disease of bone. Scintigraphy was performed 3 hours after 20 mCi Tc-99m-Sn-EHDP, using a Toshiba 204 or 404 gamma camera. In each patient multiple spot films of the total skeleton were made and evaluated according to a six-point scale. Moreover, in 42 patients the ratio of uptake in a lesion over comparable normal bone was measured using an MDS Trinary computer. Radiographs were made only of affected parts and evaluated according to a three-point scale. In 59 (16%) of the 373 lesions found on the scintigam no radiographic abnormalities were found. These roentgen-negative lesions generally show rather low scintigraphic uptake and are mostly asymptomatic. There exists a clear correlation between scintigraphic uptake and radiological deformity: the scintigraphic scores 5 and 6 occur in only 24% of the ro-grade 1 lesions, but in 65% of the grade 3 lesions; after computer evaluation the mean ratio in grade 1 and 3 lesions is 3.0 and 6.5 resp. (p<0.01). There also appears to be a correlation between scint. uptake and symptomatology: typical Pagetic pain is present in 10% of scint. score 2 and 3 lesions, but in 40% of score 5 and 6 lesions; the mean computer measured scint. ratio is 4.0 for asymptomatic and 7.5 for painful lesions (p<0.001)

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...

Isotopic Tracing of Particulate Matter from a Compression Ignition Engine Fueled with Ethanol-in-Diesel Blends

International Nuclear Information System (INIS)

Cheng, A.S.; Dibble, R.W.; Buchholz, B.

1999-01-01

Accelerator Mass Spectrometry (AMS) was used to investigate the relative contribution to diesel engine particulate matter (PM) from the ethanol and diesel fractions of blended fuels. Four test fuels along with a diesel fuel baseline were investigated. The test fuels were comprised of 14 C depleted diesel fuel mixed with contemporary grain ethanol (>400 the 14 C concentration of diesel). An emulsifier (Span 85) or cosolvent (butyl alcohol) was used to facilitate mixing. The experimental test engine was a 1993 Cummins B5.9 diesel rated at 175 hp at 2500 rpm. Test fuels were run at steady-state conditions of 1600 rpm and 210 ft-lbs, and PM samples were collected on quartz filters following dilution of engine exhaust in a mini-dilution tunnel. AMS analysis of the filter samples showed that the ethanol contributed less to PM relative to its fraction in the fuel blend. For the emulsified blends, 6.4% and 10.3% contributions to PM were observed for 11.5% and 23.0% ethanol fuels, respectively. For the cosolvent blends, even lower contributions were observed (3.8% and 6.3% contributions to PM for 12.5% and 25.0% ethanol fuels, respectively)

Effect of carboxylic acids as compatibilizer agent on mechanical properties of thermoplastic starch and polypropylene blends.

Science.gov (United States)

Martins, Andréa Bercini; Santana, Ruth Marlene Campomanes

2016-01-01

In this work, polypropylene/thermoplastic starch (PP/TPS) blends were prepared as an alternative material to use in disposable packaging, reducing the negative polymeric environmental impact. Unfortunately, this material displays morphological characteristics typical of immiscible polymer blends and a compatibilizer agent is needed. Three different carboxyl acids: myristic (C14), palmitic (C16) and stearic acids (C18) were used as natural compatibilizer agent (NCA). The effects of NCA on the mechanical, physical, thermal and morphological properties of PP/TPS blends were investigated and compared against PP/TPS with and without PP-grafted maleic anhydride (PPgMA). When compared to PP/TPS, blends with C18, PPgMA and C14 presented an improvement of 25, 22 and 17% in tensile strength at break and of 180, 194 and 259% in elongation at break, respectively. The highest increase, 54%, in the impact strength was achieved with C14 incorporation. Improvements could be seen, through scanning electron microscopy (SEM) images, in the compatibility between the immiscible components by acids incorporation. These results showed that carboxylic acids, specifically C14, could be used as compatibilizer agent and could substitute PPgMA. Copyright © 2015 Elsevier Ltd. All rights reserved.

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.

Source profiles of particulate matter emissions from a pilot-scale boiler burning North American coal blends.

Science.gov (United States)

Lee, S W

2001-11-01

Recent awareness of suspected adverse health effects from ambient particulate matter (PM) emission has prompted publication of new standards for fine PM with aerodynamic diameter less than 2.5 microm (PM2.5). However, scientific data on fine PM emissions from various point sources and their characteristics are very limited. Source apportionment methods are applied to identify contributions of individual regional sources to tropospheric particulate concentrations. The existing industrial database developed using traditional source measurement techniques provides total emission rates only, with no details on chemical nature or size characteristics of particulates. This database is inadequate, in current form, to address source-receptor relationships. A source dilution system was developed for sampling and characterization of total PM, PM2.5, and PM10 (i.e., PM with aerodynamic diameter less than 10 pm) from residual oil and coal combustion. This new system has automatic control capabilities for key parameters, such as relative humidity (RH), temperature, and sample dilution. During optimization of the prototype equipment, three North American coal blends were burned using a 0.7-megawatt thermal (MWt) pulverized coal-fired, pilot-scale boiler. Characteristic emission profiles, including PM2.5 and total PM soluble acids, and elemental and carbon concentrations for three coal blends are presented. Preliminary results indicate that volatile trace elements such as Pb, Zn, Ti, and Se are preferentially enriched in PM2.5. PM2.5 is also more concentrated in soluble sulfates relative to total PM. Coal fly ash collected at the outlet of the electrostatic precipitator (ESP) contains about 85-90% PM10 and 30-50% PM2.5. Particles contain the highest elemental concentrations of Si and Al while Ca, Fe, Na, Ba, and K also exist as major elements. Approximately 4-12% of the materials exists as soluble sulfates in fly ash generated by coal blends containing 0.2-0.8% sulfur by mass

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 Operating Conditions on Pollutants Concentration Emitted from a Spark Ignition Engine Fueled with Gasoline Bioethanol Blends

Directory of Open Access Journals (Sweden)

Haroun A. K. Shahad

2015-01-01

Full Text Available This study is an experimental investigation of the effect of bioethanol gasoline blending on exhaust emissions in terms of carbon dioxide CO2, carbon monoxide CO, unburnt hydrocarbons UHC, and nitric oxide NOx of a spark ignition engine. Tests are conducted at controlled throttle and variable speed condition over the range of 1200 to 2000 rpm with intervals 400 rpm. Different compression ratios are tested for each speed, namely (7,8,10, and 11. Pure gasoline and bioethanol gasoline blends are used. The bioethanol used is produced from Iraqi date crop (Zehdi. Blending is done on energy replacement bases. Ethanol energy ratio (EER used is 5%, 10%, and 15%. At each of the three designated engine speeds, the torque is set as 0, 3, 7, 10, and 14 N·m. It is found that ethanol blending reduces CO and UHC concentration in the exhaust gases by about 45% and 40.15%, respectively, and increases NOx and CO2 concentrations in the exhaust gases by about 16.18% and 7.5%, respectively. It is found also that load and speed increase causes an increase in CO2 and NOx concentrations and reduces CO and UHC concentrations. It is also found that increasing the compression ratio causes the emissions of CO2 and NOx to decrease and those of CO and UHC to increase.

Acid resistance of quaternary blended recycled aggregate concrete

Directory of Open Access Journals (Sweden)

K Jagannadha Rao

2018-06-01

Full Text Available The possibility of reusing the aggregate from demolished structures in fresh concrete, in order to reduce the CO2 impact on the environment [23] and to preserve natural resources, was explored worldwide and it is established that recycled aggregates can be used as a partial replacement of natural aggregates. Due to its potential to be used in eco-friendly structures and shortage of supply of natural aggregates in some parts of the world, there is an increasing interest in using the recycled aggregate. The durability aspects are also of equal concern along with the strength and economy of any material to be used in the construction. Studies reveal that the behaviour of ternary and quaternary blended concretes is superior from durability point of view compared to conventional concrete. Therefore a study is conducted to assess the acid resistance of recycled aggregate based Quaternary Blended Cement Concrete (QBCC of two grades M40 and M60. Fly ash and silica fume are fixed at 20% and 10% respectively from the previous studies while two percentages of Nano silica (2 and 3% were used along with the cement to obtain QBCC. Three percentages of recycled aggregates as partial replacement of conventional aggregate (0%, 50% and 75% were used in this study. Two different acids (HCL and H2SO4 with different concentrations (3 and 5% were used in this study. Acid resistance of QBCC with Recycled Concrete Aggregate (RCA is assessed in terms of visual appearance, weight loss, and compressive strength loss by destructive and non-destructive tests at regular intervals for a period of 56 days. The test results showed marginal weight loss and strength loss in both M40 and M60 grades of concretes. The Ultrasonic Pulse Velocity (UPV results show that the quality of QBCC is good even after being subjected to acid exposure. Keywords: Recycled concrete aggregate (RCA, Quaternary blended cement concrete (QBCC, Acid resistance, Ultrasonic pulse velocity (UPV, Mineral

Design and Assessment of a General Science STEM Course with a Blended Learning Approach

Science.gov (United States)

Courtier, A. M.; Liu, J. C.; St John, K. K.

2015-12-01

Blended learning, a combination of classroom- and computer-mediated teaching and learning, is becoming prominent in higher education, and structured assessment is necessary to determine pedagogical costs and benefits. Assessment of a blended general education science class at James Madison University used a mixed-method causal-comparative design: in Spring 2014, two classes with identical content and similar groups of non-science majors were taught by the same instructor in either blended or full face-to-face formats. The learning experience of 160 students in the two classes was compared based on course and exam grades, classroom observation, and student survey results. Student acquisition of content in both classes was measured with pre-post tests using published concept inventories, and surveys, quizzes, and grade reports in the Blackboard learning management system were additionally used for data collection. Exams were identical between the two sections, and exam questions were validated in advance by a faculty member who teaches other sections of the same course. A course experience questionnaire was administered to measure students' personal experiences in both classes, addressing dimensions of good teaching, clear goals and standards, generic skills, appropriate assessment and workload, and emphasis on independence. Using a STEM classroom observation checklist, two researchers conducted in-class observations for four 75-minute face-to-face meetings with similar content focus in both classes, which allowed assessment of student engagement and participation. We will present details of the course design and research plan, as well as assessment results from both quantitative and qualitative analysis. The preliminary findings include slightly higher average grade distribution and more ready responses to in-class activities in the blended class.

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

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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.

RELEASE AND MUCOADHESION PROPERTIES OF DICLOFENAC MATRIX TABLETS FROM NATURAL AND SYNTHETIC POLYMER BLENDS.

Science.gov (United States)

Odeniyi, Michael A; Khan, Nasir H; Peh, Kok K

2015-01-01

The delayed release and mucoadhesive properties of Cedrela gum and hydroxypropylmethylcellulose blend in diclofenac sodium tablet formulations were evaluated. Tablets were prepared by direct compression and the crushing strength and detachment force were found to increase from 74.49 ± 1.22 to 147.25 ± 2.57 N and 0.302 ± 0.36 to 1.141 ± 0.05 N from low to high level of polymers, respectively. The release kinetics followed Korsmeyer-Peppas release and the n varied between 0.834 and 1.273, indicating that the release mechanism shifts from Fickian to super case I (anomalous release). The drug release profile fits a pulsatile-release pattern characterized by a lag time followed by a more or less rapid and complete drug release. The Cedrela gum-hydroxypropylmethylcelluse blend tablets delayed diclofenac release for 2 h and sustained the release for 12 h. The polymer blend delayed drug release in the 0.1 M HCl simulating gastric environment and subsequent release pH 6.8 phosphate buffer.

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.

Structural, electronic, mechanical, thermal and optical properties of B(P,As)1-xNx; (x = 0, 0.25, 0.5, 0.75, 1) alloys and hardness of B(P,As) under compression using DFT calculations

Science.gov (United States)

Viswanathan, E.; Sundareswari, M.; Jayalakshmi, D. S.; Manjula, M.; Krishnaveni, S.

2017-09-01

First principles calculations are carried out in order to analyze the structural, electronic, mechanical, thermal and optical properties of BP and BAs compounds by ternary alloying with nitrogen namely B(P,As)1-xNx (x = 0.25, 0.5, 0.75) alloys at ambient condition. Thereby we report the mechanical and thermal properties of B(P,As)1-xNx (x = 0.25, 0.5, 0.75) alloys namely bulk modulus, shear modulus, Young's modulus, hardness, ductile-brittle nature, elastic wave velocity, Debye temperature, melting point, etc.; optical properties of B(P)1-xNx (x = 0.25, 0.5, 0.75) and B(As)1-xNx (x = 0.25, 0.75) alloys namely the dielectric function of real and imaginary part, refractive index, extinction coefficient and reflectivity and the hardness profile of the parent compounds BP and BAs under compression. The charge density plot, density of states histograms and band structures are plotted and discussed for all the ternary alloys of the present study. The calculated results agree very well with the available literature. Analysis of the present study reveals that the ternary alloy combinations namely BP.25N.75 and BAs.25N.75 could be superhard materials; hardness of BP and BAs increases with compression.

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

Thermoelectric properties of Nd0.75Sr1.25CoO4 thin films

International Nuclear Information System (INIS)

Huang, S.L.; Ruan, K.Q.; Jiao, X.L.; Wu, H.Y.; Lv, Z.M.; Pang, Z.Q.; Liu, J.; Yang, H.S.; Wu, W.B.; Cao, L.Z.; Li, X.G.

2007-01-01

Temperature dependence of the electrical resistivity (ρ) and thermopower (S) in the ab-plane of Nd 0.75 Sr 1.25 CoO 4 thin films have been investigated systematically in the temperature range 70 K< T<310 K. The specimen presents a p-type semiconducting transport property. The S nearly keeps constant at high temperatures and decreases at low ones with an additional step-like decrease, which was argued to be intimately related with the magnetic properties of the specimen. The resistivity follows the Arrhenius law. And the large value of the power factor suggests the films may be a good candidate for the thermoelectric material

Blended Interventions to Change Behavior in Patients With Chronic Somatic Disorders: Systematic Review.

Science.gov (United States)

Kloek, Corelien; Bossen, Daniël; de Bakker, Dinny H; Veenhof, Cindy; Dekker, Joost

2017-12-21

Blended behavior change interventions combine therapeutic guidance with online care. This new way of delivering health care is supposed to stimulate patients with chronic somatic disorders in taking an active role in their disease management. However, knowledge about the effectiveness of blended behavior change interventions and how they should be composed is scattered. This comprehensive systematic review aimed to provide an overview of characteristics and effectiveness of blended behavior change interventions for patients with chronic somatic disorders. We searched for randomized controlled trials published from 2000 to April 2017 in PubMed, Embase, CINAHL, and Cochrane Central Register of Controlled Trials. Risk of bias was assessed using the Cochrane Collaboration tool. Study characteristics, intervention characteristics, and outcome data were extracted. Studies were sorted based on their comparison group. A best-evidence synthesis was conducted to summarize the effectiveness. A total of 25 out of the 29 included studies were of high quality. Most studies (n=21; 72%) compared a blended intervention with no intervention. The majority of interventions focused on changing pain behavior (n=17; 59%), and the other interventions focused on lifestyle change (n=12; 41%). In addition, 26 studies (90%) focused on one type of behavior, whereas 3 studies (10%) focused on multiple behaviors. A total of 23 studies (79%) mentioned a theory as basis for the intervention. The therapeutic guidance in most studies (n=18; 62%) was non face-to-face by using email, phone, or videoconferencing, and in the other studies (partly), it was face-to-face (n=11; 38%). In 26 studies (90%), the online care was provided via a website, and in 3 studies (10%) via an app. In 22 studies (76%), the therapeutic guidance and online care were integrated instead of two separate aspects. A total of 26 outcome measures were included in the evidence synthesis comparing blended interventions with no

Jatropha oil methyl ester and its blends used as an alternative fuel in diesel engine

Directory of Open Access Journals (Sweden)

Yarrapathruni Rao Hanumantha Venkata

2009-01-01

Full Text Available Biomass derived vegetable oils are quite promising alternative fuels for agricultural diesel engines. Use of vegetable oils in diesel engines leads to slightly inferior performance and higher smoke emissions due to their high viscosity. The performance of vegetable oils can be improved by modifying them through the transesterification process. In this present work, the performance of single cylinder water-cooled diesel engine using methyl ester of jatropha oil as the fuel was evaluated for its performance and exhaust emissions. The fuel properties of biodiesel such as kinematic viscosity, calorific value, flash point, carbon residue, and specific gravity were found. Results indicate that B25 has closer performance to diesel and B100 has lower brake thermal efficiency mainly due to its high viscosity compared to diesel. The brake thermal efficiency for biodiesel and its blends was found to be slightly higher than that of diesel fuel at tested load conditions and there was no difference of efficiency between the biodiesel and its blended fuels. For jatropha biodiesel and its blended fuels, the exhaust gas temperature increased with the increase of power and amount of biodiesel. However, its diesel blends showed reasonable efficiency, lower smoke, and CO2 and CO emissions.

In vitro fermentation characteristics of novel fibers, coconut endosperm fiber and chicory pulp, using canine fecal inoculum.

Science.gov (United States)

de Godoy, M R C; Mitsuhashi, Y; Bauer, L L; Fahey, G C; Buff, P R; Swanson, K S

2015-01-01

The objective of this experiment was to determine the effects of in vitro fermentation of coconut endosperm fiber (CEF), chicory pulp (CHP), and selective blends of these substrates on SCFA production and changes in microbiota using canine fecal inocula. A total of 6 individual substrates, including short-chain fructooligosaccharide (scFOS; a well-established prebiotic source), pectin (PEC; used as a positive control), pelletized cellulose (PC; used as a negative control), beet pulp (BP; considered the gold standard fiber source in pet foods), CEF, and CHP, and 3 CEF:CHP blends (75:25% CEF:CHP [B1], 50:50% CEF:CHP [B2], and 25:75% CEF:CHP [B3]) were tested. Triplicate samples of each substrate were fermented for 0, 8, and 16 h after inoculation. A significant substrate × time interaction (P fiber substrates. Future research should investigate the effects of CEF, CHP, and their blends on gastrointestinal health and fecal quality in dogs.

Improved CT-detection of acute bowel ischemia using frequency selective non-linear image blending.

Science.gov (United States)

Schneeweiss, Sven; Esser, Michael; Thaiss, Wolfgang; Boesmueller, Hans; Ditt, Hendrik; Nikolau, Konstantin; Horger, Marius

2017-07-01

Computed tomography (CT) as a fast and reliable diagnostic technique is the imaging modality of choice for acute bowel ischemia. However, diagnostic is often difficult mainly due to low attenuation differences between ischemic and perfused segments. To compare the diagnostic efficacy of a new post-processing tool based on frequency selective non-linear blending with that of conventional linear contrast-enhanced CT (CECT) image blending for the detection of bowel ischemia. Twenty-seven consecutive patients (19 women; mean age = 73.7 years, age range = 50-94 years) with acute bowel ischemia were scanned using multidetector CT (120 kV; 100-200 mAs). Pre-contrast and portal venous scans (65-70 s delay) were acquired. All patients underwent surgery for acute bowel ischemia and intraoperative diagnosis as well as histologic evaluation of explanted bowel segments was considered "gold standard." First, two radiologists read the conventional CECT images in which linear blending was adapted for optimal contrast, and second (three weeks later) the frequency selective non-linear blending (F-NLB) image. Attenuation values were compared, both in the involved and non-involved bowel segments creating ratios between unenhanced and CECT. The mean attenuation difference between ischemic and non-ischemic wall in the portal venous scan was 69.54 HU (reader 2 = 69.01 HU) higher for F-NLB compared with conventional CECT. Also, the attenuation ratio between contrast-enhanced and pre-contrast CT data for the non-ischemic walls showed significantly higher values for the F-NLB image (CECT: reader 1 = 2.11 (reader 2 = 3.36), F-NLB: reader 1 = 4.46 (reader 2 = 4.98)]. Sensitivity in detecting ischemic areas increased significantly for both readers using F-NLB (CECT: reader 1/2 = 53%/65% versus F-NLB: reader 1/2 = 62%/75%). Frequency selective non-linear blending improves detection of bowel ischemia compared with conventional CECT by increasing

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.

Statistical physics modeling of hydrogen desorption from LaNi{sub 4.75}Fe{sub 0.25}: Stereographic and energetic interpretations

Energy Technology Data Exchange (ETDEWEB)

Wjihi, Sarra [Unité de Recherche de Physique Quantique, 11 ES 54, Faculté des Science de Monastir (Tunisia); Dhaou, Houcine [Laboratoire des Etudes des Systèmes Thermiques et Energétiques (LESTE), ENIM, Route de Kairouan, 5019 Monastir (Tunisia); Yahia, Manel Ben; Knani, Salah [Unité de Recherche de Physique Quantique, 11 ES 54, Faculté des Science de Monastir (Tunisia); Jemni, Abdelmajid [Laboratoire des Etudes des Systèmes Thermiques et Energétiques (LESTE), ENIM, Route de Kairouan, 5019 Monastir (Tunisia); Lamine, Abdelmottaleb Ben, E-mail: abdelmottaleb.benlamine@gmail.com [Unité de Recherche de Physique Quantique, 11 ES 54, Faculté des Science de Monastir (Tunisia)

2015-12-15

Statistical physics treatment is used to study the desorption of hydrogen on LaNi{sub 4.75}Fe{sub 0.25}, in order to obtain new physicochemical interpretations at the molecular level. Experimental desorption isotherms of hydrogen on LaNi{sub 4.75}Fe{sub 0.25} are fitted at three temperatures (293 K, 303 K and 313 K), using a monolayer desorption model. Six parameters of the model are fitted, namely the number of molecules per site n{sub α} and n{sub β}, the receptor site densities N{sub αM} and N{sub βM}, and the energetic parameters P{sub α} and P{sub β}. The behaviors of these parameters are discussed in relationship with desorption process. A dynamic study of the α and β phases in the desorption process was then carried out. Finally, the different thermodynamical potential functions are derived by statistical physics calculations from our adopted model.

Gamma radiation effects in Ascaris sp. eggs in the treated and untreated sewage

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