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Sample records for composite thrombelastography parameters

  1. Thrombelastography Early Amplitudes in bleeding and coagulopathic trauma patients

    DEFF Research Database (Denmark)

    Laursen, Thomas Holst; Meyer, Martin A S; Meyer, Anna Sina P

    2018-01-01

    BACKGROUND: Early amplitudes in the viscoelastic hemostatic assays Thrombelastography (TEG) and Rotation Thromboelastometry (ROTEM) provide fast results, which is critical in resuscitation of bleeding patients. This study investigated associations between TEG early amplitudes and standard TEG var...

  2. Hypocoagulability, as evaluated by thrombelastography, at admission to the ICU is associated with increased 30-day mortality

    DEFF Research Database (Denmark)

    Johansson, Pär I; Stensballe, Jakob; Vindeløv, Nis

    2010-01-01

    Thrombelastography (TEG), a cell-based whole blood assay, may better reflect haemostatic competence than conventional coagulation assays and this was therefore evaluated including the clot forming parameters: R, angle and maximal amplitude in patients at ICU admission. This was a prospective...... were recorded. At ICU admission, 106 patients (42%) showed hypocoagulability as evaluated by TEG and these patients had higher first day SOFA score (P ... (P = 0.05), angle (P evaluated by TEG was an independent risk factor for 30-day mortality [adjusted odds ratio (OR) 3.5; 95% confidence interval (CI) 1...

  3. Fibrinogen in trauma, an evaluation of thrombelastography and rotational thromboelastometry fibrinogen assays

    DEFF Research Database (Denmark)

    Meyer, Martin A S; Ostrowski, Sisse R; Sørensen, Anne Marie

    2015-01-01

    BACKGROUND: Identifying hypofibrinogenemia in trauma is important. The optimal method of fibrinogen determination is unknown. We therefore evaluated fibrinogen levels determined by two whole blood viscoelastic hemostatic assays, thrombelastography functional fibrinogen (FF) and rotational thrombo...

  4. The prognostic value of thrombelastography in identifying neurosurgical patients with worse prognosis

    DEFF Research Database (Denmark)

    Windeløv, Nis A; Welling, Karen-Lise; Ostrowski, Sisse R

    2011-01-01

    Coagulopathy in patients with intracranial haemorrhage or traumatic brain injury (TBI) is associated with clinical deterioration and worse outcome. Whole blood viscoelastic haemostatic assays, like thrombelastography (TEG), might aid conventional coagulation assays in identification of patients w...... prognosis. Low concordance with conventional coagulation assays indicates that TEG might be valuable in identifying patients with clinically relevant coagulopathy....

  5. Thrombelastography and rotational thromboelastometry early amplitudes in 182 trauma patients with clinical suspicion of severe injury

    DEFF Research Database (Denmark)

    Meyer, Anna Sina P; Meyer, Martin A S; Sørensen, Anne Marie

    2014-01-01

    BACKGROUND: Viscoelastic hemostatic assays may provide means for earlier detection of trauma-induced coagulopathy (TIC). METHODS: This is a prospective observational study of 182 trauma patients admitted to a Level 1 trauma center. Clinical data, thrombelastography (TEG), and rotational thromboel...

  6. Composite Solid Fuel: Research of Formation Parameters

    Directory of Open Access Journals (Sweden)

    Tabakaev Roman

    2016-01-01

    Full Text Available Involving of local low-grade fuels resources in fuel and energy balance is actual question of research in the present. In this paper the possibility of processing low-grade fuel in the solid fuel composite was considered. The aim of the work is to define the optimal parameters for formation of the solid composite fuel. A result of researches determined that dextrin content in the binder allows to obtain solid composite fuel having the highest strength. The drying temperature for the various fuels was determined: for pellets production was 20-80 °C, for briquettes – 20-40 °C.

  7. Composite likelihood estimation of demographic parameters

    Directory of Open Access Journals (Sweden)

    Garrigan Daniel

    2009-11-01

    Full Text Available Abstract Background Most existing likelihood-based methods for fitting historical demographic models to DNA sequence polymorphism data to do not scale feasibly up to the level of whole-genome data sets. Computational economies can be achieved by incorporating two forms of pseudo-likelihood: composite and approximate likelihood methods. Composite likelihood enables scaling up to large data sets because it takes the product of marginal likelihoods as an estimator of the likelihood of the complete data set. This approach is especially useful when a large number of genomic regions constitutes the data set. Additionally, approximate likelihood methods can reduce the dimensionality of the data by summarizing the information in the original data by either a sufficient statistic, or a set of statistics. Both composite and approximate likelihood methods hold promise for analyzing large data sets or for use in situations where the underlying demographic model is complex and has many parameters. This paper considers a simple demographic model of allopatric divergence between two populations, in which one of the population is hypothesized to have experienced a founder event, or population bottleneck. A large resequencing data set from human populations is summarized by the joint frequency spectrum, which is a matrix of the genomic frequency spectrum of derived base frequencies in two populations. A Bayesian Metropolis-coupled Markov chain Monte Carlo (MCMCMC method for parameter estimation is developed that uses both composite and likelihood methods and is applied to the three different pairwise combinations of the human population resequence data. The accuracy of the method is also tested on data sets sampled from a simulated population model with known parameters. Results The Bayesian MCMCMC method also estimates the ratio of effective population size for the X chromosome versus that of the autosomes. The method is shown to estimate, with reasonable

  8. CLASSIFICATION OF ORTHOGNATHIC SURGERY PATIENTS INTO LOW AND HIGH BLEEDING RISK GROUPS USING THROMBELASTOGRAPHY

    DEFF Research Database (Denmark)

    Elenius Madsen, Daniel

    2012-01-01

    Title: CLASSIFICATION OF ORTHOGNATHIC SURGERY PATIENTS INTO LOW AND HIGH BLEEDING RISK GROUPS USING THROMBELASTOGRAPHY Objectives: Orthognathic surgery involves surgical manipulation of jaw and face skeletal structure. A subgroup of patients undergoing orthognathic surgery suffers from excessive...... into account the complex interplay between coagulation factors, blood platelets and components of the fibrinolytic system. Patients undergoing orthognathic surgery were included in this prospective study, and their preoperative thrombelastographic data were collected and compared to their intraoperative blood...... predictive values. An α angleex above 67o did with 95% certainty predict a blood loss below 400 mL, and a receiver-operating characteristic (ROC) curve showed an area under the curve (AUC) of 0.8. Conclusion: By means of the α angleex it is possible to separate orthognathic surgery patients according...

  9. Analysis and design of composite slab by varying different parameters

    Science.gov (United States)

    Lambe, Kedar; Siddh, Sharda

    2018-03-01

    Composite deck slabs are in demand because of its faster, lighter and economical construction work. Composite slab consists of cold formed deck profiled sheet and concrete either lightweight or normal. Investigation of shear behaviour of the composite slab is very complex. Shear bond strength depends on the various parameter such as a shape of sheeting, a thickness of the sheet, type of embossment and its frequency of use, shear stiffener or intermediate stiffener, type of load, an arrangement of load, length of shear span, the thickness of concrete and support friction etc. In present study finite element analysis is carried out with ABAQUS 6.13, a simply supported composite slab is considered for the investigation of the shear bond behaviour of the composite slab by considering variation in three different parameters, the shape of a sheet, thickness of sheet and shear span. Different shear spans of two different shape of cold formed deck profiled sheet i.e. with intermediate stiffeners and without intermediate stiffeners are considered with two different thicknesses (0.8 mm and 1.2 mm) for simulation. In present work, simulation of models has done for static loading with 20 mm mesh size is considered.

  10. Thrombelastography and biomarker profiles in acute coagulopathy of trauma: a prospective study

    Directory of Open Access Journals (Sweden)

    Larsen Claus F

    2011-10-01

    Full Text Available Abstract Background Severe injury induces an acute coagulopathy associated with increased mortality. This study compared the Thrombelastography (TEG and biomarker profiles upon admission in trauma patients. Methods Prospective observational study of 80 trauma patients admitted to a Level I Trauma Centre. Data on demography, biochemistry including standard coagulation tests, hematology, transfusions, Injury Severity Score (ISS and TEG were recorded. Retrospective analysis of thawed plasma/serum for biomarkers reflecting tissue injury (histone-complexed DNA fragments, sympathoadrenal activation (adrenaline, noradrenaline, coagulation activation/inhibition and fibrinolysis (sCD40L, protein C, activated Protein C, tissue-type plasminogen activator, plasminogen activator inhibitor-1, D-dimer, prothrombinfragment 1+2, plasmin/α2-antiplasmin complex, thrombin/antithrombin complex, tissue factor pathway inhibitor, antithrombin, von willebrand factor, factor XIII. Comparison of patients stratified according to ISS/TEG maximum clot strength. Linear regression analysis of variables associated with clot strength. Results Trauma patients had normal (86%, hypercoagulable (11% or hypocoagulable (1% TEG clot strength; one had primary hyperfibrinolysis. Hypercoagulable patients had higher age, fibrinogen and platelet count (all p 10 red blood cells the initial 24 h. Patients with normal or hypercoagulable TEG clot strength had comparable biomarker profiles, but the few patients with hypocoagulable TEG clot strength and/or hyperfibrinolysis had very different biomarker profiles. Increasing ISS was associated with higher levels of catecholamines, histone-complexed DNA fragments, sCD40L, activated protein C and D-dimer and reduced levels of non-activated protein C, antithrombin, fibrinogen and factor XIII (all p 26. In patients with ISS > 26, adrenaline and sCD40L were independently negatively associated with clot strength. Conclusions Trauma patients displayed

  11. Splenectomy is associated with hypercoagulable thrombelastography values and increased risk of thromboembolism.

    Science.gov (United States)

    Pommerening, Matthew J; Rahbar, Elaheh; Minei, Kristin; Holcomb, John B; Wade, Charles E; Schreiber, Martin A; Cohen, Mitchell J; Underwood, Samantha J; Nelson, Mary; Cotton, Bryan A

    2015-09-01

    Previous investigators have demonstrated that postinjury thrombocytosis is associated with an increase in thromboembolic (TE) risk. Increased rates of thrombocytosis have been found specifically in patients after splenectomy for trauma. We hypothesized that patients undergoing splenectomy (1) would demonstrate a more hypercoagulable profile during their hospital stay and (2) that this hypercoagulable state would be associated with increased TE events. This was a 14-month, prospective, observational trial evaluating serial rapid thrombelastography (rTEG) at 3 American College of Surgeons-verified, level 1 trauma centers. Inclusion criteria were highest-level trauma activation and arrival within 6 hours of injury. Exclusion criteria were 20% total body surface area. Serial rTEG (activated clotting time, k-time, α-angle, MA, lysis) and traditional coagulation testing (prothrombin time, partial thromboplastin time, fibrinogen and platelet count) were obtained at admission and then at 3, 6, 12, 24, 48, 72, 96, and 120 hours. Thromboembolic complications were defined as the development of deep-vein thrombosis, pulmonary embolism, acute myocardial infarction, or ischemic stroke during hospitalization. Patients were stratified into splenectomy versus nonsplenectomy cohorts. Univariate analysis was then conducted followed by longitudinal analysis using generalized estimating equations to evaluate the effects of time, splenectomy, and group-time interactions on changes in rTEG and traditional coagulation testing. We used an adjusted generalized estimating equation model to control for age, sex, ISS, admission blood pressure, base deficit, and hemoglobin. A total of 1,242 patients were enrolled; 795 had serial rTEG data. Of these, 605 had serial values >24 hours and made up the study population. Splenectomy patients were younger, more hypotensive, and in shock on arrival. Although there was no difference in 24-hour or 30-day mortality, splenectomy patients were more

  12. Hansen solubility parameters for a carbon fiber/epoxy composite

    DEFF Research Database (Denmark)

    Launay, Helene; Hansen, Charles M.; Almdal, Kristoffer

    2007-01-01

    In this study, the physical affinity between an epoxy matrix and oxidized, unsized carbon fibers has been evaluated using Hansen solubility (cohesion) parameters (HSP). A strong physical compatibility has been shown, since their respective HSP are close. The use of a glassy carbon substrate...... as a model for unsized carbon fiber has been demonstrated as appropriate for the study of interactions between the materials in composite carbon fiber-epoxy systems. The HSP of glassy carbon are similar to those of carbon fibers and epoxy matrix. (C) 2007 Elsevier Ltd. All rights reserved....

  13. The association of body composition parameters with nonalcoholic hepatic steatosis

    Directory of Open Access Journals (Sweden)

    Mesut Sipahi

    2015-06-01

    Full Text Available Objective:Nonalcoholic fatty liver disease (NAFLD which is strongly correlated with obesity; has been a common worldwide health problem with the improvements in social status. Body composition studies are accepted as a simple follow-up tool for treatment of obesity. Since the correlation of body mass index (BMI with the hepatosteatosis (HS is well known; the aim of this study was to assess the usefulness of body composition parameters (BCP to determine HS on NAFLD patients; using dual bioimpedance analyzer (BIA. Methods:A total of 253 patients with diagnosis of NAFLD were included into the study. The demographic parameters such as age, sex and BMI were collected; and the ultrasonographic (US evolution was performed to determine the HS stages. The BCP, such as amount and the percentage of total body fat, fat free mass, and total body water were assessed with the dual bioimpedance analyzer. Results:There were strong significant correlations between BMI and HS, between BCP and HS (p0.05. Conclusion: According to our results, it can be concluded that BCP values may have a diagnostic value on diagnosis of NAFLD.

  14. Parameters Identification for a Composite Piezoelectric Actuator Dynamics

    Directory of Open Access Journals (Sweden)

    Mohammad Saadeh

    2015-03-01

    Full Text Available This work presents an approach for identifying the model of a composite piezoelectric (PZT bimorph actuator dynamics, with the objective of creating a robust model that can be used under various operating conditions. This actuator exhibits nonlinear behavior that can be described using backlash and hysteresis. A linear dynamic model with a damping matrix that incorporates the Bouc–Wen hysteresis model and the backlash operators is developed. This work proposes identifying the actuator’s model parameters using the hybrid master-slave genetic algorithm neural network (HGANN. In this algorithm, the neural network exploits the ability of the genetic algorithm to search globally to optimize its structure, weights, biases and transfer functions to perform time series analysis efficiently. A total of nine datasets (cases representing three different voltage amplitudes excited at three different frequencies are used to train and validate the model. Four cases are considered for training the NN architecture, connection weights, bias weights and learning rules. The remaining five cases are used to validate the model, which produced results that closely match the experimental ones. The analysis shows that damping parameters are inversely proportional to the excitation frequency. This indicates that the suggested hysteresis model is too general for the PZT model in this work. It also suggests that backlash appears only when dynamic forces become dominant.

  15. Normalisation of body composition parameters for nutritional assessment

    International Nuclear Information System (INIS)

    Preston, Thomas

    2014-01-01

    Full text: Normalisation of body composition parameters to an index of body size facilitates comparison of a subject’s measurements with those of a population. There is an obvious focus on indexes of obesity, but first it is informative to consider Fat Free Mass (FFM) in the context of common anthropometric measures of body size namely, height and weight. The contention is that FFM is a more physiological measure of body size than body mass. Many studies have shown that FFM relates to height ^p. Although there is debate over the appropriate exponent especially in early life, it appears to lie between 2 and 3. If 2, then FFM Index (FFMI; kg/m2) and Fat Mass Index (FMI; kg/m2) can be summed to give BMI. If 3 were used as exponent, then FFMI (kg/m3) plus FMI (kg/m3) gives the Ponderal Index (PI; weight/height3). In 2013, Burton argued that that a cubic exponent is appropriate for normalisation as it is a dimensionless quotient. In 2012, Wang and co-workers repeated earlier observations showing a strong linear relationship between FFM and height3. The importance of the latter study comes from the fact that a 4 compartment body composition model was used, which is recognised as the most accurate means of describing FFM. Once the basis of a FFMI has been defined it can be used to compare measurements with those of a population, either directly, as a ratio to a norm or as a Z-score. FFMI charts could be developed for use in child growth. Other related indexes can be determined for use in specific circumstances such as: body cell mass index (growth and wasting); skeletal muscle mass index (SMMI) or appendicular SMMI (growth and sarcopenia); bone mineral mass index (osteoporosis); extracellular fluid index (hydration). Finally, it is logical that the same system is used to define an adiposity index, so Fat Mass Index (FMI; kg/height3) can be used as it is consistent with FFMI (kg/height3) and PI. It should also be noted that the index FM/FFM, describes an individual

  16. The effect of compaction parameters and dielectric composition on properties of soft magnetic composites

    Science.gov (United States)

    Xiao, Ling; Sun, Y. H.; Yu, Lie

    2011-07-01

    This paper investigated the effect of compaction parameters and dielectric composition on mechanical, magnetic and electrical properties of iron-organosilicon epoxy resin soft magnetic composites. In this work, iron powders with high purity were covered by an organic material (organosilicon epoxy resin) and then by coupling agent (KH-550). The coated powders were then cold compacted at 600, 800 and 1000 MPa and cured under vacuum respectively. The results show that the saturation magnetic flux density and electrical resistivity are dependent on compaction pressure and resin content. Increase in the organic phase content leads to decrease of the saturation magnetic flux density, while increase of the electrical resistivity. Furthermore, the samples with 0.9 wt% resins + 0.1 wt% coupling agent at compaction pressure of 800 MPa shows better properties than the others.

  17. The effect of compaction parameters and dielectric composition on properties of soft magnetic composites

    International Nuclear Information System (INIS)

    Xiao Ling; Yu Lie; Sun, Y H

    2011-01-01

    This paper investigated the effect of compaction parameters and dielectric composition on mechanical, magnetic and electrical properties of iron-organosilicon epoxy resin soft magnetic composites. In this work, iron powders with high purity were covered by an organic material (organosilicon epoxy resin) and then by coupling agent (KH-550). The coated powders were then cold compacted at 600, 800 and 1000 MPa and cured under vacuum respectively. The results show that the saturation magnetic flux density and electrical resistivity are dependent on compaction pressure and resin content. Increase in the organic phase content leads to decrease of the saturation magnetic flux density, while increase of the electrical resistivity. Furthermore, the samples with 0.9 wt% resins + 0.1 wt% coupling agent at compaction pressure of 800 MPa shows better properties than the others.

  18. Optimal Design of Variable Stiffness Composite Structures using Lamination Parameters

    NARCIS (Netherlands)

    IJsselmuiden, S.T.

    2011-01-01

    Fiber reinforced composite materials have gained widespread acceptance for a multitude of applications in the aerospace, automotive, maritime and wind-energy industries. Automated fiber placement technologies have developed rapidly over the past two decades, driven primarily by a need to reduce

  19. Parameters Controlling Sediment Composition of Modern and Pleistocene Jamaican Reefs

    OpenAIRE

    Boss, Stephen K.

    1985-01-01

    Recent carbonate sediments from Jamaican north coast fringing reefs display variation in constituent composition, texture, and mineralogy related to their location on the reef. Samples were collected along lines which traversed the back reef and fore reef (0.5m to 70m). The sediment is dominated by highly comminuted coral fragments, plates of the calcareous green alga, Halimeda, coralline algae, and the encrusting Foraminifera, Homotrema rubrum, with lesser amounts of other taxonomic group...

  20. Language Parameters in Written Compositions of Nine Year Old Children.

    Science.gov (United States)

    Rubin, Rosalyn; Buium, Nissan

    The purpose of this study was to develop a foundation for reliable and effective measurement of significant parameters in the development of written language skills in school age children. The subjects for the study were 25 nine-year-old children, 12 boys and 13 girls, who were randomly selected from among 1,559 participants. The findings…

  1. Effect of process parameters on coating composition of cathodic ...

    Indian Academy of Sciences (India)

    1Department of Mining and Metallurgical Engineering, Amirkabir University of Technology, ... The effect of some process parameters such as electrical conductivity, volume and temperature of ... the subject of numerous studies and found industrial applica- .... tion of positive ions and transfer of their kinetic energy to the.

  2. Multi-Response Parameter Interval Sensitivity and Optimization for the Composite Tape Winding Process

    Science.gov (United States)

    Yu, Tao; Kang, Chao; Zhao, Pan

    2018-01-01

    The composite tape winding process, which utilizes a tape winding machine and prepreg tapes, provides a promising way to improve the quality of composite products. Nevertheless, the process parameters of composite tape winding have crucial effects on the tensile strength and void content, which are closely related to the performances of the winding products. In this article, two different object values of winding products, including mechanical performance (tensile strength) and a physical property (void content), were respectively calculated. Thereafter, the paper presents an integrated methodology by combining multi-parameter relative sensitivity analysis and single-parameter sensitivity analysis to obtain the optimal intervals of the composite tape winding process. First, the global multi-parameter sensitivity analysis method was applied to investigate the sensitivity of each parameter in the tape winding processing. Then, the local single-parameter sensitivity analysis method was employed to calculate the sensitivity of a single parameter within the corresponding range. Finally, the stability and instability ranges of each parameter were distinguished. Meanwhile, the authors optimized the process parameter ranges and provided comprehensive optimized intervals of the winding parameters. The verification test validated that the optimized intervals of the process parameters were reliable and stable for winding products manufacturing. PMID:29385048

  3. Nonlinear analysis of AS4/PEEK thermoplastic composite laminate using a one parameter plasticity model

    Science.gov (United States)

    Sun, C. T.; Yoon, K. J.

    1990-01-01

    A one-parameter plasticity model was shown to adequately describe the orthotropic plastic deformation of AS4/PEEK (APC-2) unidirectional thermoplastic composite. This model was verified further for unidirectional and laminated composite panels with and without a hole. The nonlinear stress-strain relations were measured and compared with those predicted by the finite element analysis using the one-parameter elastic-plastic constitutive model. The results show that the one-parameter orthotropic plasticity model is suitable for the analysis of elastic-plastic deformation of AS4/PEEK composite laminates.

  4. Important parameters in ORIGEN2 calculations of spent fuel compositions

    International Nuclear Information System (INIS)

    Welch, T.D.; Notz, K.J.; Andermann, R.J. Jr.

    1990-01-01

    The Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM) is responsible for implementing federal policy for the management and permanent disposal of spent nuclear fuel from civilian nuclear power reactors and of high-level radioactive waste. The Characteristics Data Base (CDB) provides an extensive collection of data on the four waste steams that may require long-term isolation: LWR spent fuel, high-level waste, non-LWR spent fuel, and miscellaneous wastes (such as greater-than-class-C). The eight-volume report and the five supplemental menu-driven PC data bases encompass radiological characteristics, chemical compositions, physical descriptions, inventories, and projections. An overview of these data bases, which are available through the Oak Ridge National Laboratory, is provided by Notz. This paper reports that the radiological characteristics in the CDB are calculated using ORIGEN2

  5. Optimization of process parameters in drilling of fibre hybrid composite using Taguchi and grey relational analysis

    Science.gov (United States)

    Vijaya Ramnath, B.; Sharavanan, S.; Jeykrishnan, J.

    2017-03-01

    Nowadays quality plays a vital role in all the products. Hence, the development in manufacturing process focuses on the fabrication of composite with high dimensional accuracy and also incurring low manufacturing cost. In this work, an investigation on machining parameters has been performed on jute-flax hybrid composite. Here, the two important responses characteristics like surface roughness and material removal rate are optimized by employing 3 machining input parameters. The input variables considered are drill bit diameter, spindle speed and feed rate. Machining is done on CNC vertical drilling machine at different levels of drilling parameters. Taguchi’s L16 orthogonal array is used for optimizing individual tool parameters. Analysis Of Variance is used to find the significance of individual parameters. The simultaneous optimization of the process parameters is done by grey relational analysis. The results of this investigation shows that, spindle speed and drill bit diameter have most effect on material removal rate and surface roughness followed by feed rate.

  6. Thermodynamics parameters of nano-Ni/PS composites prepared by in situ polymerization method

    International Nuclear Information System (INIS)

    Liao Qilong; Xiong Jie; Ning Haixia

    2011-01-01

    Spherical nickel nanoparticles with about 75∼200 nm in size were obtained by a liquid reduction method. The nickel nanoparticles/PS composites were synthesized via in situ polymerization method. XRD, FTIR, SEM and TG-DSC were respectively used to measure the properties of nickel nanoparticles, the microstructure of as-prepared composites samples, the distribution of nickel nanoparticles in PS and the thermodynamic parameters of as-prepared composites. The results show that the nickel nanoparticles will enhance the glass transition temperature of nano-Ni/PS composites. The enthalpy of composites is heightened by increasing of doping dose, and it reaches the top when the doping dose is from 1% to 2%. The specific heat of the composites will reduce with the doping dose of nickel nanoparticles increasing. (authors)

  7. Finite element analysis and optimization of process parameters during stamp forming of composite materials

    International Nuclear Information System (INIS)

    Venkatesan, S; Kalyanasundaram, S

    2010-01-01

    In the manufacture of parts for high performance structures using composite materials, the quality and robustness of the parts is of utmost importance. The quality of the produced parts depends largely on the process parameters and manufacturing methodologies. This study presents the use of a temperature dependant orthotropic material for a coupled structural-thermal analysis of the stamp forming process. The study investigated the effects of process parameters such as pre-heat temperature, blank holder force and process time on the formability of composite materials. Temperature was found to be the dominant factor governing the formability of the composite material while higher blank holder forces were deemed to be important for achieving high quality of the parts manufactured. Finally, an optimum set of parameters was used to compare the simulations with experimental results using an optical strain measurement system.

  8. Leg tissue composition and physico-chemical parameters of sheep meat fed annatto coproduct

    Directory of Open Access Journals (Sweden)

    Dorgival Morais de Lima Júnior

    2017-10-01

    Full Text Available Our objective was to evaluate leg tissue composition and physico-chemical quality parameters of sheep meat fed with increasing levels of annatto coproduct. 32 male uncastrated animals without a defined breed were randomized in four treatments (0, 100, 200 and 300 g kg-1 of annatto coproduct in the DM diet. After 78 days of confinement, the animals were slaughtered and body components were recorded. Reconstituted leg weight, total muscle weight, biceps weight and semitendinosus weight showed a negative linear behavior (P 0.05 were found for leg tissue composition (%, muscle:bone ratio, relative fat or leg muscle. Meat physico-chemical parameters (color, shear force, water retention capacity and cooking losses were not affected by the inclusion of the annatto coproduct in the diet. The annatto coproduct can be included in up to 300 g kg-1 of dietary dry matter without negative effects to the leg tissue composition (% and physical parameters of confined sheep meat.

  9. A Note on Parameter Estimation in the Composite Weibull–Pareto Distribution

    Directory of Open Access Journals (Sweden)

    Enrique Calderín-Ojeda

    2018-02-01

    Full Text Available Composite models have received much attention in the recent actuarial literature to describe heavy-tailed insurance loss data. One of the models that presents a good performance to describe this kind of data is the composite Weibull–Pareto (CWL distribution. On this note, this distribution is revisited to carry out estimation of parameters via mle and mle2 optimization functions in R. The results are compared with those obtained in a previous paper by using the nlm function, in terms of analytical and graphical methods of model selection. In addition, the consistency of the parameter estimation is examined via a simulation study.

  10. Composition influence on positron annihilation parameters in ZnO-based nanocrystal semiconductor powders

    Energy Technology Data Exchange (ETDEWEB)

    Damonte, L.C.; Hernandez Fenollosa, M.A.; Donderis, V.; Mari, B. [Departamento de Fisica Aplicada, Universidad Politecnica de Valencia, Cami de Vera s/n, Valencia, 46071 (Spain)

    2007-07-01

    Zn{sub 1-x}Mg{sub x}O powders at various compositions were obtained by mechanical milling from the binary oxides. The progressive incorporation of Mg atoms into the ZnO lattice was monitored by X-ray diffraction (XRD). The evolution of annihilation parameters with milling time and composition were analyzed and related to the possible types of mechanical and substitutional induced defect present. It was concluded that the average lifetime constitute a useful parameter to sense the complete cation substitution in the wurtzite structure. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  11. Composition influence on positron annihilation parameters in ZnO-based nanocrystal semiconductor powders

    International Nuclear Information System (INIS)

    Damonte, L.C.; Hernandez Fenollosa, M.A.; Donderis, V.; Mari, B.

    2007-01-01

    Zn 1-x Mg x O powders at various compositions were obtained by mechanical milling from the binary oxides. The progressive incorporation of Mg atoms into the ZnO lattice was monitored by X-ray diffraction (XRD). The evolution of annihilation parameters with milling time and composition were analyzed and related to the possible types of mechanical and substitutional induced defect present. It was concluded that the average lifetime constitute a useful parameter to sense the complete cation substitution in the wurtzite structure. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  12. Optimum processing parameters for the fabrication of twill flax fabric-reinforced polypropylene (PP) composites

    Science.gov (United States)

    Zuhudi, Nurul Zuhairah Mahmud; Minhat, Mulia; Shamsuddin, Mohd Hafizi; Isa, Mohd Dali; Nur, Nurhayati Mohd

    2017-12-01

    In recent years, natural fabric thermoplastic composites such as flax have received much attention due to its attractive capabilities for structural applications. It is crucial to study the processing of flax fabric materials in order to achieve good quality and cost-effectiveness in fibre reinforced composites. Though flax fabric has been widely utilized for several years in composite applications due to its high strength and abundance in nature, much work has been concentrated on short flax fibre and very little work focused on using flax fabric. The effectiveness of the flax fabric is expected to give higher strength performance due to its structure but the processing needs to be optimised. Flax fabric composites were fabricated using compression moulding due to its simplicity, gives good surface finish and relatively low cost in terms of labour and production. Further, the impregnation of the polymer into the fabric is easier in this process. As the fabric weave structure contributes to the impregnation quality which leads to the overall performance, the processing parameters of consolidation i.e. pressure, time, and weight fraction of fabric were optimized using the Taguchi method. This optimization enhances the consolidation quality of the composite by improving the composite mechanical properties, three main tests were conducted i.e. tensile, flexural and impact test. It is observed that the processing parameter significantly affected the consolidation and quality of composite.

  13. Influence of Drilling Parameters on Torque during Drilling of GFRP Composites Using Response Surface Methodology

    Science.gov (United States)

    Mohan, N. S.; Kulkarni, S. M.

    2018-01-01

    Polymer based composites have marked their valuable presence in the area of aerospace, defense and automotive industry. Components made of composite, are assembled to main structure by fastener, which require accurate, precise high quality holes to be drilled. Drilling the hole in composite with accuracy require control over various processes parameters viz., speed, feed, drill bit size and thickens of specimen. TRIAC VMC machining center is used to drill the hole and to relate the cutting and machining parameters on the torque. MINITAB 14 software is used to analyze the collected data. As a function of cutting and specimen parameters this method could be useful for predicting torque parameters. The purpose of this work is to investigate the effect of drilling parameters to get low torque value. Results show that thickness of specimen and drill bit size are significant parameters influencing the torque and spindle speed and feed rate have least influence and overlaid plot indicates a feasible and low region of torque is observed for medium to large sized drill bits for the range of spindle speed selected. Response surface contour plots indicate the sensitivity of the drill size and specimen thickness to the torque.

  14. Shock compression parameters for a boron-loaded, silicone-rubber composite

    International Nuclear Information System (INIS)

    Gust, W.H.; Van Thiel, M.; Gathers, G.R.

    1975-01-01

    Hugoniot parameters under uniaxial-shock-wave-loading from 0.03 to 0.6 Mbar are presented for a composite with 70 wt percent boron loaded in a silicone-rubber matrix. The plot of shock velocity vs particle velocity was found to be nonlinear. Equations that describe fits of the data are presented. (U.S.)

  15. Statistical and Multidimensional Body Composition Parameter Analysis in Young Childhood Cancer Survivors

    Directory of Open Access Journals (Sweden)

    Topczewska Magdalena

    2014-12-01

    Full Text Available This article concerns the problem of assessing selected body compo- sition parameters after completion of antitumor therapy and comparing them with the same parameters of healthy children. A high percentage of overweight and obesity, as well as abnormal fat distribution in convalescents with cancer shows a significant adverse effect of therapy on body composition and suggests the need for early intervention in terms of diet and exercise, which would help patients to quickly achieve the proper parameters of body composition. Two main problems will be mentioned during the presented data analysis. Firstly, in each group there was a small number of observations. Because of this, the real differences between examined subgroups may have been omitted. Secondarily, many variables are correlated and are not normally distributed. Therefore, be- side the standard statistical tests to compare two groups, principal component analysis was applied to reduce the dimensions of the attribute space and to attempt to classify two groups of patients.

  16. Frequency Dependence of Electrical Parameters of an Organic-Inorganic Hybrid Composite Based Humidity Sensor

    Directory of Open Access Journals (Sweden)

    Rizwan Akram

    2016-05-01

    Full Text Available The present study highlights the interdependence of ambient humidity levels on the electrical parameters of organic-inorganic hybrid composite based humidity sensor at varied AC frequencies of input signal. Starting from the bottom, the layer stack of the fabricated humidity sensor was 200-nm silver (Ag thin film and 4 μm spun-coated PEPC+NiPC+Cu2O active layer. Silver thin films were deposited by thermal evaporator on well cleaned microscopic glass slides, which served as a substrate. Conventional optical lithography procedure was adapted to define pairs of silver-silver surface electrodes with two sorts of configurations, i.e., interdigitated and rectangular. Humidity-sensitive layers of organic-inorganic composite were then spun-cast upon the channel between the silver electrodes. The changes in relative humidity levels induced variation in capacitance and impedance of the sensors. These variations in electrical parameters of sensors were also found to be highly dependent upon frequency of input AC signal. Our findings reveal that the organic-inorganic composite shows higher humidity sensitivity at smaller orders of frequency. This finding is in accordance with the established fact that organic semiconductors-based devices are not applicable for high frequency applications due to their lower charge carrier mobility values. Two distinct geometries of semiconducting medium between the silver electrodes were investigated to optimize the sensing parameters of the humidity sensor. Furthermore, the effect of temperature change on the resistance of organic composite has also been studied.

  17. Resting metabolic rate, pulmonary functions, and body composition parameters in children with attention deficit hyperactivity disorder.

    Science.gov (United States)

    Alpaslan, Ahmet Hamdi; Ucok, Kagan; Coşkun, Kerem Şenol; Genc, Abdurrahman; Karabacak, Hatice; Guzel, Halil Ibrahim

    2017-03-01

    Several studies of school-aged children with attention deficit hyperactivity disorder (ADHD) have found a higher prevalence of overweight/obesity compared with the general population. However, the scientific literature contains insufficient evidence to establish clear conclusions on pulmonary functions, resting metabolic rate (RMR), and body composition in children with ADHD. This study therefore investigates the pulmonary functions tests (PFTs), RMR, and body composition parameters in children with ADHD and evaluates their quality of life. Forty children with ADHD and 40 healthy controls participated in the study. The children's parents completed Conners' parent rating scale (CPRS) and the pediatric quality of life (PedsQL), and their teachers completed Conners' Teacher rating scale (CTRS). The child participants also completed the PedsQL. RMR, PFTs, and body composition parameters were investigated. No significant differences in age, gender, and socioeconomic level were found. All CPRS subscales, except anxiety and psychosomatic conditions, were significantly different (p ADHD group. The results showed that the ADHD group's quality of life is worse than the control group. Body mass index, body composition parameters, RMR, and PFTs were not statistically different between the children with ADHD and the healthy controls. Further studies with complex designs are needed to confirm the results.

  18. Development and Application of a Tool for Optimizing Composite Matrix Viscoplastic Material Parameters

    Science.gov (United States)

    Murthy, Pappu L. N.; Naghipour Ghezeljeh, Paria; Bednarcyk, Brett A.

    2018-01-01

    This document describes a recently developed analysis tool that enhances the resident capabilities of the Micromechanics Analysis Code with the Generalized Method of Cells (MAC/GMC) and its application. MAC/GMC is a composite material and laminate analysis software package developed at NASA Glenn Research Center. The primary focus of the current effort is to provide a graphical user interface (GUI) capability that helps users optimize highly nonlinear viscoplastic constitutive law parameters by fitting experimentally observed/measured stress-strain responses under various thermo-mechanical conditions for braided composites. The tool has been developed utilizing the MATrix LABoratory (MATLAB) (The Mathworks, Inc., Natick, MA) programming language. Illustrative examples shown are for a specific braided composite system wherein the matrix viscoplastic behavior is represented by a constitutive law described by seven parameters. The tool is general enough to fit any number of experimentally observed stress-strain responses of the material. The number of parameters to be optimized, as well as the importance given to each stress-strain response, are user choice. Three different optimization algorithms are included: (1) Optimization based on gradient method, (2) Genetic algorithm (GA) based optimization and (3) Particle Swarm Optimization (PSO). The user can mix and match the three algorithms. For example, one can start optimization with either 2 or 3 and then use the optimized solution to further fine tune with approach 1. The secondary focus of this paper is to demonstrate the application of this tool to optimize/calibrate parameters for a nonlinear viscoplastic matrix to predict stress-strain curves (for constituent and composite levels) at different rates, temperatures and/or loading conditions utilizing the Generalized Method of Cells. After preliminary validation of the tool through comparison with experimental results, a detailed virtual parametric study is

  19. The Effect of Stochastically Varying Creep Parameters on Residual Stresses in Ceramic Matrix Composites

    Science.gov (United States)

    Pineda, Evan J.; Mital, Subodh K.; Bednarcyk, Brett A.; Arnold, Steven M.

    2015-01-01

    Constituent properties, along with volume fraction, have a first order effect on the microscale fields within a composite material and influence the macroscopic response. Therefore, there is a need to assess the significance of stochastic variation in the constituent properties of composites at the higher scales. The effect of variability in the parameters controlling the time-dependent behavior, in a unidirectional SCS-6 SiC fiber-reinforced RBSN matrix composite lamina, on the residual stresses induced during processing is investigated numerically. The generalized method of cells micromechanics theory is utilized to model the ceramic matrix composite lamina using a repeating unit cell. The primary creep phases of the constituents are approximated using a Norton-Bailey, steady state, power law creep model. The effect of residual stresses on the proportional limit stress and strain to failure of the composite is demonstrated. Monte Carlo simulations were conducted using a normal distribution for the power law parameters and the resulting residual stress distributions were predicted.

  20. Analysis and optimization of machining parameters of laser cutting for polypropylene composite

    Science.gov (United States)

    Deepa, A.; Padmanabhan, K.; Kuppan, P.

    2017-11-01

    Present works explains about machining of self-reinforced Polypropylene composite fabricated using hot compaction method. The objective of the experiment is to find optimum machining parameters for Polypropylene (PP). Laser power and Machining speed were the parameters considered in response to tensile test and Flexure test. Taguchi method is used for experimentation. Grey Relational Analysis (GRA) is used for multiple process parameter optimization. ANOVA (Analysis of Variance) is used to find impact for process parameter. Polypropylene has got the great application in various fields like, it is used in the form of foam in model aircraft and other radio-controlled vehicles, thin sheets (∼2-20μm) used as a dielectric, PP is also used in piping system, it is also been used in hernia and pelvic organ repair or protect new herrnis in the same location.

  1. Assessing composition and structure of soft biphasic media from Kelvin-Voigt fractional derivative model parameters

    Science.gov (United States)

    Zhang, Hongmei; Wang, Yue; Fatemi, Mostafa; Insana, Michael F.

    2017-03-01

    Kelvin-Voigt fractional derivative (KVFD) model parameters have been used to describe viscoelastic properties of soft tissues. However, translating model parameters into a concise set of intrinsic mechanical properties related to tissue composition and structure remains challenging. This paper begins by exploring these relationships using a biphasic emulsion materials with known composition. Mechanical properties are measured by analyzing data from two indentation techniques—ramp-stress relaxation and load-unload hysteresis tests. Material composition is predictably correlated with viscoelastic model parameters. Model parameters estimated from the tests reveal that elastic modulus E 0 closely approximates the shear modulus for pure gelatin. Fractional-order parameter α and time constant τ vary monotonically with the volume fraction of the material’s fluid component. α characterizes medium fluidity and the rate of energy dissipation, and τ is a viscous time constant. Numerical simulations suggest that the viscous coefficient η is proportional to the energy lost during quasi-static force-displacement cycles, E A . The slope of E A versus η is determined by α and the applied indentation ramp time T r. Experimental measurements from phantom and ex vivo liver data show close agreement with theoretical predictions of the η -{{E}A} relation. The relative error is less than 20% for emulsions 22% for liver. We find that KVFD model parameters form a concise features space for biphasic medium characterization that described time-varying mechanical properties. The experimental work was carried out at the Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. Methodological development, including numerical simulation and all data analysis, were carried out at the school of Life Science and Technology, Xi’an JiaoTong University, 710049, China.

  2. One-parameter families of supersymmetric isospectral potentials from Riccati solutions in function composition form

    Energy Technology Data Exchange (ETDEWEB)

    Rosu, Haret C., E-mail: hcr@ipicyt.edu.mx [IPICYT, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la presa San José 2055, Col. Lomas 4a Sección, 78216 San Luis Potosí, S.L.P. (Mexico); Mancas, Stefan C., E-mail: mancass@erau.edu [Department of Mathematics, Embry–Riddle Aeronautical University, Daytona Beach, FL 32114-3900 (United States); Chen, Pisin, E-mail: pisinchen@phys.ntu.edu.tw [Leung Center for Cosmology and Particle Astrophysics (LeCosPA) and Department of Physics, National Taiwan University, Taipei 10617, Taiwan (China)

    2014-04-15

    In the context of supersymmetric quantum mechanics, we define a potential through a particular Riccati solution of the composition form (F∘f)(x)=F(f(x)) and obtain a generalized Mielnik construction of one-parameter isospectral potentials when we use the general Riccati solution. Some examples for special cases of F and f are given to illustrate the method. An interesting result is obtained in the case of a parametric double well potential generated by this method, for which it is shown that the parameter of the potential controls the heights of the localization probability in the two wells, and for certain values of the parameter the height of the localization probability can be higher in the smaller well. -- Highlights: •Function-composition generalization of parametric isospectral potentials is presented. •Mielnik one-parameter family of harmonic potentials is obtained as a particular case. •Graphical discussion of regular and singular regions in the parameter space is given.

  3. Identification of parameters of cohesive elements for modeling of adhesively bonded joints of epoxy composites

    Directory of Open Access Journals (Sweden)

    Kottner R.

    2013-12-01

    Full Text Available Adhesively bonded joints can be numerically simulated using the cohesive crack model. The critical strain energy release rate and the critical opening displacement are the parameters which must be known when cohesive elements in MSC.Marc software are used. In this work, the parameters of two industrial adhesives Hunstman Araldite 2021 and Gurit Spabond 345 for bonding of epoxy composites are identified. Double Cantilever Beam (DCB and End Notched Flexure (ENF test data were used for the identification. The critical opening displacements were identified using an optimization algorithm where the tests and their numerical simulations were compared.

  4. Optimization of Cutting Parameters on Delamination of Drilling Glass-Polyester Composites

    Directory of Open Access Journals (Sweden)

    Majid Habeeb Faidh-Allah

    2018-02-01

    Full Text Available This paper attempted to study the effect of cutting parameters (spindle speed and feed rate on delamination phenomena during the drilling glass-polyester composites. Drilling process was done by CNC machine with 10 mm diameter of high-speed steel (HSS drill bit. Taguchi technique with L16 orthogonal layout was used to analyze the effective parameters on delamination factor. The optimal experiment was no. 13 with spindle speed 1273 rpm and feed 0.05 mm/rev with minimum delamination factor 1.28.

  5. Determination of kinetic parameters during the thermal decomposition of epoxy/carbon fiber composite material

    International Nuclear Information System (INIS)

    Lee, Jae Hun; Kim, Kwang Seok; Kim, Hyo

    2013-01-01

    An in-depth study to determine the thermal decomposition kinetics parameters such as the activation energy E_a, the reaction order n, and the pre-exponential factor A of epoxy/carbon fiber composite material has been conducted. We employ not only the modified peak property method that is proposed here, but also the conventional method in analyzing the experimental data, and compare the results to show the performance of the proposed model. The pyrolysis tests for the epoxy/carbon fiber composite materials are conducted by using thermogravimetric analyser at various heating rates. As a result, the best prediction to the experimental data can be obtained by the modified peak property method. Besides, among the methods applied here, the modified peak property method provides most convenient way to recover the parameters: it does not require a curve fitting of the data nor a long iterative computation

  6. Composition, nutritional aspects and effect on serum parameters of marine algae Ulva rigida.

    Science.gov (United States)

    Taboada, Cristina; Millán, Rosendo; Míguez, Isabel

    2010-02-01

    Algae are commonly consumed in Asia and have also gained popularity in Europe. However, data on the bioavailability of their components are limited. The present study was designed to determine the composition of Ulva rigida and the effects of inclusion of 10% of the algae in a standard diet for 4 weeks on nutritive value and serum parameters in order to consider the usefulness of Ulva as a dietary supplement. Ulva rigida is rich in protein, carbohydrates, fibre, vitamins and minerals and has a low lipid content. Analysis of the amino acid composition revealed good-quality protein. The algae were well accepted by experimental animals and did not significantly change nutritional parameters but reduced LDL cholesterol. Ulva rigida is an excellent source of nutrients and could improve a balanced diet. Further studies are required to research the potential of the seaweed as a natural source of bioactive compounds.

  7. High strength Al–Al2O3p composites: Optimization of extrusion parameters

    DEFF Research Database (Denmark)

    Luan, B.F.; Hansen, Niels; Godfrey, A.

    2011-01-01

    Composite aluminium alloys reinforced with Al2O3p particles have been produced by squeeze casting followed by hot extrusion and a precipitation hardening treatment. Good mechanical properties can be achieved, and in this paper we describe an optimization of the key processing parameters...... on an investigation of their mechanical properties and microstructure, as well as on the surface quality of the extruded samples. The evaluation shows that material with good strength, though with limited ductility, can be reliably obtained using a production route of squeeze casting, followed by hot extrusion....... The parameters investigated are the extrusion temperature, the extrusion rate and the extrusion ratio. The materials chosen are AA 2024 and AA 6061, each reinforced with 30vol.% Al2O3 particles of diameter typically in the range from 0.15 to 0.3μm. The extruded composites have been evaluated based...

  8. Workstation Related Anthropometric and Body Composition Parameters of Indian Women of Different Geographical Regions

    Directory of Open Access Journals (Sweden)

    Inderjeet Singh

    2015-01-01

    Full Text Available Background: Anthropometry plays an important role in industrial design, clothing design, ergonomics and architecture where statistical data about the distribution of body dimensions in the population are used to optimize products. Changes in lifestyles, nutrition, and ethnic composition of populations lead to changes in the distribution of body dimensions (e.g. the obesity epidemic, and require regular updating of anthropometric data collections. Aim and Objectives: This study analyzed the variation in anthropometric dimensions and body composition parameters of working women employees of different geographical zones. Material and Methods: The study was undertaken on nine hundred forty (940 women employees of Defence Research and Development Organization (DRDO working in seventeen different laboratories and belonged to different states of India. The age range of studied women was between 20-60 years. Fourteen body dimensions namely stature, popliteal height, knee height, buttock to popliteal length, hip breadth, waist breadth, shoulder breadth, forearm length, arm length, eye height (sitting, sitting shoulder height, hand length, hand breadth and elbow width were measured in cm using Martin anthropometers and Martin's sliding caliper. Body composition parameters like weight, percentage body fat, fat mass and fat free mass were recorded. Results: All anthropometric parameters were found significantly different (p<0.001. Body composition variables of women were also found significantly different in all three zones but fat free mass was not significantly different. Conclusion:It can be concluded that diet, environmental conditions and living style of different regions can influence the anthropometry and body composition of the individuals, however the influence of ethnic, genetic and hereditary factor are not controlled in this study.

  9. The Comparison Analysis of the Main Chemical Composition Parameters of Wild Boar Meat and Pork

    OpenAIRE

    Erika Bodnárné Skobrák; Károly Bodnár; Edit Mikóné Jónás; János Gundel; András Jávor

    2011-01-01

    The chemical composition of wild boar meat from wild boar parks with various habitats and different feeding facilities was analysed. Samples were collected from m. serratus anterior – during the winter hunting period. The protein, the total fat, the saturated and unsaturated fatty acid content were measured and also and those elements which have great importance on human alimentation. The results were compared with other author’s data of the same parameters of pork. The aim of the study was t...

  10. Crack diffusion coefficient - A candidate fracture toughness parameter for short fiber composites

    Science.gov (United States)

    Mull, M. A.; Chudnovsky, A.; Moet, A.

    1987-01-01

    In brittle matrix composites, crack propagation occurs along random trajectories reflecting the heterogeneous nature of the strength field. Considering the crack trajectory as a diffusive process, the 'crack diffusion coefficient' is introduced. From fatigue crack propagation experiments on a set of identical SEN polyester composite specimens, the variance of the crack tip position along the loading axis is found to be a linear function of the effective 'time'. The latter is taken as the effective crack length. The coefficient of proportionality between variance of the crack trajectory and the effective crack length defines the crack diffusion coefficient D which is found in the present study to be 0.165 mm. This parameter reflects the ability of the composite to deviate the crack from the energetically most efficient path and thus links fracture toughness to the microstructure.

  11. EFFECT OF COMPOSITION OF FUEL CONTAINING BUTANOL ON WORKING PROCESS PARAMETERS OF DIESEL ENGINE

    Directory of Open Access Journals (Sweden)

    D. G. Hershan

    2017-01-01

    Full Text Available Computational researches the effect of composition of fuel containing butanol on working process parameters of 4ЧН 11/12,5 diesel engine on the external speed characteristic have been conducted. Nominal power is 140 kW at engine speed 2300 min–1. The engine is equipped with gas turbine pressure charging with intercooling of charging air, accumulator-type fuel-handling system. Calculations of the working process have been made in accordance with the developed computer program and models. Investigations have been carried out in two stages: without any changes in regulation of fuel-handling system and with cyclic fuel delivery that ensure such value of excess air factor at various operational modes which corresponds to the operation with diesel fuel. All the obtained results have been analyzed in the paper. The paper shows changes in mean indicated pressure, specific indicated fuel consumption, indicated efficiency, specific nitrogen oxides emissions for various modes in question while using 5, 10, 15, 20, 25 and 30 % mixture of diesel fuel with butanol. Dependences of parameters pertaining to diesel operation have been determined according to external speed characteristic for various mixtures and the obtained data make it possible to justify parameters of the fuel-handling system. It has been recommended to use a diesel fuel-butanol mixture containing 15 % of butanol without any changes in regulating and design engine parameters. It has been revealed that in order to improve parameters of the engine operational process mixture composition must be changed while changing the operational mode. An injector nozzle with a compound needle for the fuel-handling system has been developed and it allows to change fuel composition according to engine operational mode.

  12. Genetic parameters and genetic trends in the Chinese × European Tiameslan composite pig line. I. Genetic parameters

    Directory of Open Access Journals (Sweden)

    Legault Christian

    2000-01-01

    Full Text Available Abstract Genetic parameters of body weight at 4 (W4 w, 8 (W8 w and 22 (W22 w weeks of age, days from 20 to 100 kg (DT, average backfat thickness at 100 kg (ABT, teat number (TEAT, number of good teats (GTEAT, total number of piglets born (TNB, born alive (NBA and weaned (NW per litter, and birth to weaning survival rate (SURV were estimated in the Chinese × European Tiameslan composite line using restricted maximum likelihood methodology applied to a multiple trait animal model. Performance data from a total of 4 881 males and 4 799 females from 1 341 litters were analysed. Different models were fitted to the data in order to estimate the importance of maternal effects on production traits, as well as genetic correlations between male and female performance. The results showed the existence of significant maternal effects on W4w, W8w and ABT and of variance heterogeneity between sexes for W22w, DT, ABT and GTEAT. Genetic correlations between sexes were 0.79, 0.71 and 0.82, respectively, for W22w, DT and ABT and above 0.90 for the other traits. Heritability estimates were larger than (ABT and TEAT or similar to (other traits average literature values. Some genetic antagonism was evidenced between production traits, particularly W4w, W8w and ABT, and reproductive traits.

  13. Effects of simulated space environmental parameters on six commercially available composite materials

    International Nuclear Information System (INIS)

    Funk, J.G.; Sykes, G.F. Jr.

    1989-04-01

    The effects of simulated space environmental parameters on microdamage induced by the environment in a series of commercially available graphite-fiber-reinforced composite materials were determined. Composites with both thermoset and thermoplastic resin systems were studied. Low-Earth-Orbit (LEO) exposures were simulated by thermal cycling; geosynchronous-orbit (GEO) exposures were simulated by electron irradiation plus thermal cycling. The thermal cycling temperature range was -250 F to either 200 F or 150 F. The upper limits of the thermal cycles were different to ensure that an individual composite material was not cycled above its glass transition temperature. Material response was characterized through assessment of the induced microcracking and its influence on mechanical property changes at both room temperature and -250 F. Microdamage was induced in both thermoset and thermoplastic advanced composite materials exposed to the simulated LEO environment. However, a 350 F cure single-phase toughened epoxy composite was not damaged during exposure to the LEO environment. The simuated GEO environment produced microdamage in all materials tested

  14. Damage characteristics in 3D stitched composites with various stitch parameters under in-plane tension

    KAUST Repository

    Yudhanto, Arief

    2015-04-01

    Three-dimensional (3D) reinforcement by stitching is effective in improving the impact resistance of composites. Stitching, however, adversely affects the composite\\'s in-plane mechanical responses, and alters its damage mechanisms due to stitch-induced irregularities. We experimentally investigate the effect of two important stitch parameters, stitch density and thread diameter, on the damage characteristics of 3D stitched multidirectional composites under in-plane tension using X-ray radiography, X-ray micro-computed tomography and digital image correlation (DIC). Our study shows that composites stitched with thicker thread exhibit improved tensile strength due to effective hindrance of edge-delamination. We also found that stitch thread affects damage behaviors. A higher number of transverse cracks develops in the middle portion of thin 90° fiber tows; the inter-crack distance is reduced by dense stitching. DIC is able to identify the cracks that appear in resin-rich channels and distinguish strain fields due to different stitch densities.

  15. A Central Composite Face-Centered Design for Parameters Estimation of PEM Fuel Cell Electrochemical Model

    Directory of Open Access Journals (Sweden)

    Khaled MAMMAR

    2013-11-01

    Full Text Available In this paper, a new approach based on Experimental of design methodology (DoE is used to estimate the optimal of unknown model parameters proton exchange membrane fuel cell (PEMFC. This proposed approach combines the central composite face-centered (CCF and numerical PEMFC electrochemical. Simulation results obtained using electrochemical model help to predict the cell voltage in terms of inlet partial pressures of hydrogen and oxygen, stack temperature, and operating current. The value of the previous model and (CCF design methodology is used for parametric analysis of electrochemical model. Thus it is possible to evaluate the relative importance of each parameter to the simulation accuracy. However this methodology is able to define the exact values of the parameters from the manufacture data. It was tested for the BCS 500-W stack PEM Generator, a stack rated at 500 W, manufactured by American Company BCS Technologies FC.

  16. Experimental study of dual fuel engine performance using variable LPG composition and engine parameters

    International Nuclear Information System (INIS)

    Elnajjar, Emad; Selim, Mohamed Y.E.; Hamdan, Mohammad O.

    2013-01-01

    Highlights: • The effect of using variable LPG is studied. • Five fuels with propane to butane % volume ratio are: 100-70-55-25-0. • 100% Propane composition shows the highest noise levels with similar performance. • At 45° BTDC injection timing 55% Propane LPG the only fuel experience knocking. • LPG fuels gave similar engine performance, with differences in levels of noise. - Abstract: The present work investigates experimentally the effect of LPG fuel with different composition and engine parameters on the performance of a dual compression engine. Five different blends of LPG fuels are used with Propane to Butane volume ratio of 100:0, 70:30, 55:45, 25:75, and 0:100. A single cylinder, naturally aspirated, four strokes, indirectly injected, water cooled modified Ricardo E6 engine, is used in this study. The study is carried out by measuring the cylinder pressure, engine load, engine speed, crank angle, and the fuel’s flow rate. The engine performance under variable LPG fuel composition, engine load, pilot fuel injection timing, compression ratio, pilot fuel mass and engine speed, are estimated by comparing the following engine parameters: the cylinder maximum pressure, the indicated mean effective pressure, the maximum rate of pressure rise, and the thermal efficiency. The experimental data indicates that the engine parameters are playing a major role on the engine’s performance. Different LPG fuel composition did not show a major effect on the engine efficiency but directly impacted the levels of generated combustion noise

  17. Investigation of the thrombin-generating capacity, evaluated by thrombogram, and clot formation evaluated by thrombelastography of platelets stored in the blood bank for up to 7 days.

    Science.gov (United States)

    Johansson, P I; Svendsen, M S; Salado, J; Bochsen, L; Kristensen, A T

    2008-02-01

    Transfusion based on the Thrombelastograph (TEG) results reduces transfusion requirements in cardiac surgery and in liver transplantation. Taking the pivotal role of thrombin generation in the coagulation process into consideration, the clinical utility of the TEG may, in part, depend on its reflection of the dynamics of thrombin generation. The kinetics of thrombin generation of platelets stored for 2 and 7 days, respectively, was assessed by calibrated automated thrombogram (CAT) and the lag time (min), time to peak (ttPeak; min), peak (nm thrombin) and endogenous thrombin potential (ETP; nm thrombin*min) were registered. Clot formation was evaluated by TEG and the R time (min), maxial amplitude (MA; mm), time to maximum thrombus generation (TMG; min) and maximum thrombus generation (MTG; dynes cm(-2) s(-1)) and total thrombus generation (TTG; dyne cm(-2)) were registered. Platelets become more procoagulant, evaluated both by TEG and CAT during storage. The reduction in CAT lag time and the ttPeak correlated with a decrease in the TEG R time and TMG (P < 0.0001) as did the CAT peak thrombin generation and the TEG MTG (P = 0.0035). No correlation between ETP and TTG was found (P = 0.65). The kinetics of thrombin generation, as evaluated by CAT, correlates with the thrombus generation, as evaluated by thrombelastography and this may in part explain the clinical utility of the TEG in identifying clinically relevant coagulopathies, secondary to impaired thrombin generation.

  18. Piezoelectric Performance and Hydrostatic Parameters of Novel 2-2-Type Composites.

    Science.gov (United States)

    Topolov, Vitaly Yu; Bowen, Christopher R; Krivoruchko, Andrey V

    2017-10-01

    This paper provides a detailed study of the structure-piezoelectric property relationships and the hydrostatic response of 2-2-Type composites based on relaxor-ferroelectric 0.72 Pb (Mg 1/3 Nb 2/3 )O 3 -0.28PbTiO 3 single crystal (SC) material. Type I layers in the composite system are represented by a single-domain [111]-poled SC. Changes in the orientation of the crystallographic axes in the Type I layer are undertaken to determine the maximum values of the hydrostatic piezoelectric coefficients d h ∗ , g h ∗ , and e h ∗ , and squared figure of merit d h ∗ g h ∗ of the composite. The Type II layers are a 0-3 composite whereby inclusions of modified PbTiO 3 ceramic are distributed in a polymer matrix. A new effect is described for the first time due to the impact of anisotropic elastic properties of the Type II layers on the hydrostatic piezoelectric response that is coupled with the polarization orientation effect in the Type I layers. Large hydrostatic parameters g h ∗ ≈ 300 -400 mV · m/N, e h ∗ ≈ 40 -45 C/ [Formula: see text], and d h ∗ g h ∗  ∼ 10 -11 Pa -1 are achieved in the composite based on the 0.72 Pb(Mg 1/3 Nb 2/3 )O 3 -0.28PbTiO 3 SC. Examples of the large piezoelectric anisotropy ( |d 33 ∗ /d 3f ∗ | ≥ 5 or | g 33 ∗ /g 3f ∗ | ≥ 5 ) are discussed. The hydrostatic parameters of this novel compositesystem are compared to those of conventional 2-2 piezocomposites.

  19. Relationship of periodontal clinical parameters with bacterial composition in human dental plaque.

    Science.gov (United States)

    Fujinaka, Hidetake; Takeshita, Toru; Sato, Hirayuki; Yamamoto, Tetsuji; Nakamura, Junji; Hase, Tadashi; Yamashita, Yoshihisa

    2013-06-01

    More than 600 bacterial species have been identified in the oral cavity, but only a limited number of species show a strong association with periodontitis. The purpose of the present study was to provide a comprehensive outline of the microbiota in dental plaque related to periodontal status. Dental plaque from 90 subjects was sampled, and the subjects were clustered based on bacterial composition using the terminal restriction fragment length polymorphism of 16S rRNA genes. Here, we evaluated (1) periodontal clinical parameters between clusters; (2) the correlation of subgingival bacterial composition with supragingival bacterial composition; and (3) the association between bacterial interspecies in dental plaque using a graphical Gaussian model. Cluster 1 (C1) having high prevalence of pathogenic bacteria in subgingival plaque showed increasing values of the parameters. The values of the parameters in Cluster 2a (C2a) having high prevalence of non-pathogenic bacteria were markedly lower than those in C1. A cluster having low prevalence of non-pathogenic bacteria in supragingival plaque showed increasing values of the parameters. The bacterial patterns between subgingival plaque and supragingival plaque were significantly correlated. Chief pathogens, such as Porphyromonas gingivalis, formed a network with other pathogenic species in C1, whereas a network of non-pathogenic species, such as Rothia sp. and Lautropia sp., tended to compete with a network of pathogenic species in C2a. Periodontal status relates to non-pathogenic species as well as to pathogenic species, suggesting that the bacterial interspecies connection affects dental plaque virulence.

  20. Optimization of process parameters for spark plasma sintering of nano structured SAF 2205 composite

    Directory of Open Access Journals (Sweden)

    Samuel Ranti Oke

    2018-04-01

    Full Text Available This research optimized spark plasma sintering (SPS process parameters in terms of sintering temperature, holding time and heating rate for the development of a nano-structured duplex stainless steel (SAF 2205 grade reinforced with titanium nitride (TiN. The mixed powders were sintered using an automated spark plasma sintering machine (model HHPD-25, FCT GmbH, Germany. Characterization was performed using X-ray diffraction and scanning electron microscopy. Density and hardness of the composites were investigated. The XRD result showed the formation of FeN0.068. SEM/EDS revealed the presence of nano ranged particles of TiN segregated at the grain boundaries of the duplex matrix. A decrease in hardness and densification was observed when sintering temperature and heating rate were 1200 °C and 150 °C/min respectively. The optimum properties were obtained in composites sintered at 1150 °C for 15 min and 100 °C/min. The composite grades irrespective of the process parameters exhibited similar shrinkage behavior, which is characterized by three distinctive peaks, which is an indication of good densification phenomena. Keywords: Spark plasma sintering, Duplex stainless steel (SAF 2205, Titanium nitride (TiN, Microstructure, Density, Hardness

  1. Role of manufacturing process parameters on the characteristics of aluminum matrix composites

    International Nuclear Information System (INIS)

    Zaid, A.I.O.

    2003-01-01

    Metal matrix composites, (MMC), are engineered combinations of two or more materials (one of which is a metal) in which tailored properties are achieved by systematic combinations consisting of continuous or discontinuous fibers, whiskers, or particles in a metal result in combinations of very high specific strength. Furthermore, systematic design and procedures can be developed to achieve unique combinations of engineering properties such as high elevated-temperature strengths, damping or electrical properties. In this paper, the theory and practice of MMC are reviewed and discussed. The different techniques used in the manufacturing of MMC in general and aluminum matrix composites in particular e.g. unidirectional solidification, squeeze casting, vortex method and compocasting are presented and discussed. The parameters involved in these techniques and their effects on the characteristics of MMC product are also given and discussed. These include: crucible size and shape, melt temperature, size and shape of the impeller, stirring speed, rate of addition of the particles, the degree of agitation and cooling rate. Furthermore, the effect of these parameters on the mechanical strength and machinability are also presented and discussed. Finally, recent research results in aluminum matrix composites and their future developments are outlined and discussed. (author)

  2. Cf/C composites: correlation between CVI process parameters and Pyrolytic Carbon microstructure

    Directory of Open Access Journals (Sweden)

    F. Burgio

    2014-10-01

    Full Text Available Chemical Vapour Infiltration (CVI technique has been long used to produce carbon/carbon composites. The Pyrolytic Carbon (Py-C matrix infiltrated by CVI could have different microstructures, i.e. Rough Laminar (RL, Smooth Laminar (SL or Isotropic (ISO. These matrix microstructures, characterized by different properties, influence the mechanical behaviour of the obtained composites. Tailoring the process parameters, it is possible to direct the infiltration towards a specific Py-C type. However, the factors, influencing the production of a specific matrix microstructure, are numerous and interconnected, e.g. temperature, pressure, flow rates etc. Due to the complexity of the physical and chemical phenomena involved in CVI process, up to now it has not been possible to obtain a general correlation between CVI process parameters and Py–C microstructure. This study is aimed at investigating the relationship between infiltration temperature and the microstructure of obtained Py-C, for a pilot - sized CVI/CVD reactor. Fixing the other process parameters and varying only the temperature, from 1100°C to 1300°C, the Py-C infiltration was performed on fibrous preforms. Polarized light microscopy, with quantitative measurements of average extinction angle (Ae, and Raman spectroscopy were used to characterize the obtained Py-C microstructures

  3. Cf/C composites: correlation between CVI process parameters and Pyrolytic Carbon microstructure

    Directory of Open Access Journals (Sweden)

    F. Burgio

    2014-10-01

    Full Text Available Chemical Vapour Infiltration (CVI technique has been long used to produce carbon/carbon composites. The Pyrolytic Carbon (Py-C matrix infiltrated by CVI could have different microstructures, i.e. Rough Laminar (RL, Smooth Laminar (SL or Isotropic (ISO. These matrix microstructures, characterized by different properties, influence the mechanical behaviour of the obtained composites. Tailoring the process parameters, it is possible to direct the infiltration towards a specific Py-C type. However, the factors, influencing the production of a specific matrix microstructure, are numerous and interconnected, e.g. temperature, pressure, flow rates etc. Due to the complexity of the physical and chemical phenomena involved in CVI process, up to now it has not been possible to obtain a general correlation between CVI process parameters and Py–C microstructure. This study is aimed at investigating the relationship between infiltration temperature and the microstructure of obtained Py-C, for a pilot - sized CVI/CVD reactor. Fixing the other process parameters and varying only the temperature, from 1100°C to 1300°C, the Py-C infiltration was performed on fibrous preforms. Polarized light microscopy, with quantitative measurements of average extinction angle (Ae, and Raman spectroscopy were used to characterize the obtained Py-C microstructures.

  4. Composition dependence of the thermodynamic activity and lattice parameter of zeta nickel-indium

    International Nuclear Information System (INIS)

    Bhattacharya, B.; Masson, D.B.

    1976-01-01

    The vapor pressure of indium over six alloys in the zeta phase of the nickel-indium system was measured by the method of atomic absorption. Values of thermodynamic activity were calculated from the vapor pressure, and partial heat and entropy of indium were calculated from the temperature coefficients. The lattice parameters of the hexagonal B8 2 unit cell of all alloys were calculated from X-ray diffraction powder patterns. It was found that the a lattice parameter passed through a minimum at the same composition that the excess chemical potential showed a sharp change of slope, when graphed as a function of composition. These effects were similar to those observed previously which have been attributed to overlap by the Fermi surface of a Brillouin zone face. In the present case they were attributed to overlap of the Fermi surface across faces tentatively identified as the [110] faces of the Brillouin zone of the B8 2 structure. The influence of substitutional disorder was also considered as a cause of the thermodynamic effects, but this was rejected because it does not explain the minimum in lattice parameter. (Auth.)

  5. Characteristic evaluation of process parameters of friction stir welding of aluminium 2024 hybrid composites

    Science.gov (United States)

    Sadashiva, M.; Shivanand, H. K.; Vidyasagar, H. N.

    2018-04-01

    The Current work is aimed to investigate the effect of process parameters in friction stir welding of Aluminium 2024 base alloy and Aluminium 2024 matrix alloy reinforced with E Glass and Silicon Carbide reinforcements. The process involved a set of synthesis techniques incorporating stir casting methodology resulting in fabrication of the composite material. This composite material that is synthesized is then machined to obtain a plate of dimensions 100 mm * 50 mm * 6 mm. The plate is then friction stir welded at different set of parameters viz. the spindle speed of 600 rpm, 900 rpm and 1200 rpm and feed rate of 40 mm/min, 80 mm/min and 120 mm/min for analyzing the process capability. The study of the given set of parameters is predominantly important to understand the physics of the process that may lead to better properties of the joint, which is very much important in perspective to its use in advanced engineering applications, especially in aerospace domain that uses Aluminium 2024 alloy for wing and fuselage structures under tension.

  6. Influence of cookies composition on temperature profiles and qualitative parameters during baking

    Directory of Open Access Journals (Sweden)

    Ž. Kožul

    2014-01-01

    Full Text Available During baking of bakery products temperature of baking, temperature profiles, moisture content, volume and colour changes are strongly coupled. The objective of this paper was to study the influence of the cookies composition on temperature profiles and quality parameters (width and thickness, colour formation and textural properties: hardness, fracturability and work of breaking force during baking process. Composition of cookies differs due to flour type and initial moisture content. Cookies were baked at 205 °C and temperature was measured in the centre of samples which were 7 mm thick with a 60 mm diameter. The results of temperature profiles of the cookies during baking have shown the same trend for all of the 18 samples. Samples with the higher initial water content have lower values of total colour difference and also significantly affect textural properties.

  7. Assessment of color parameters of composite resin shade guides using digital imaging versus colorimeter.

    Science.gov (United States)

    Yamanel, Kivanc; Caglar, Alper; Özcan, Mutlu; Gulsah, Kamran; Bagis, Bora

    2010-12-01

    This study evaluated the color parameters of resin composite shade guides determined using a colorimeter and digital imaging method. Four composite shade guides, namely: two nanohybrid (Grandio [Voco GmbH, Cuxhaven, Germany]; Premise [KerrHawe SA, Bioggio, Switzerland]) and two hybrid (Charisma [Heraeus Kulzer, GmbH & Co. KG, Hanau, Germany]; Filtek Z250 [3M ESPE, Seefeld, Germany]) were evaluated. Ten shade tabs were selected (A1, A2, A3, A3,5, A4, B1, B2, B3, C2, C3) from each shade guide. CIE Lab values were obtained using digital imaging and a colorimeter (ShadeEye NCC Dental Chroma Meter, Shofu Inc., Kyoto, Japan). The data were analyzed using two-way analysis of variance and Bonferroni post hoc test. Overall, the mean ΔE values from different composite pairs demonstrated statistically significant differences when evaluated with the colorimeter (p 6.8). For all shade pairs evaluated, the most significant shade mismatches were obtained between Grandio-Filtek Z250 (p = 0.021) and Filtek Z250-Premise (p = 0.01) regarding ΔE mean values, whereas the best shade match was between Grandio-Charisma (p = 0.255) regardless of the measurement method. The best color match (mean ΔE values) was recorded for A1, A2, and A3 shade pairs in both methods. When proper object-camera distance, digital camera settings, and suitable illumination conditions are provided, digital imaging method could be used in the assessment of color parameters. Interchanging use of shade guides from different composite systems should be avoided during color selection. © 2010, COPYRIGHT THE AUTHORS. JOURNAL COMPILATION © 2010, WILEY PERIODICALS, INC.

  8. Optimisation Of Cutting Parameters Of Composite Material Laser Cutting Process By Taguchi Method

    Science.gov (United States)

    Lokesh, S.; Niresh, J.; Neelakrishnan, S.; Rahul, S. P. Deepak

    2018-03-01

    The aim of this work is to develop a laser cutting process model that can predict the relationship between the process input parameters and resultant surface roughness, kerf width characteristics. The research conduct is based on the Design of Experiment (DOE) analysis. Response Surface Methodology (RSM) is used in this work. It is one of the most practical and most effective techniques to develop a process model. Even though RSM has been used for the optimization of the laser process, this research investigates laser cutting of materials like Composite wood (veneer)to be best circumstances of laser cutting using RSM process. The input parameters evaluated are focal length, power supply and cutting speed, the output responses being kerf width, surface roughness, temperature. To efficiently optimize and customize the kerf width and surface roughness characteristics, a machine laser cutting process model using Taguchi L9 orthogonal methodology was proposed.

  9. Elastic-plastic analysis of AS4/PEEK composite laminate using a one-parameter plasticity model

    Science.gov (United States)

    Sun, C. T.; Yoon, K. J.

    1992-01-01

    A one-parameter plasticity model was shown to adequately describe the plastic deformation of AS4/PEEK (APC-2) unidirectional thermoplastic composite. This model was verified further for unidirectional and laminated composite panels with and without a hole. The elastic-plastic stress-strain relations of coupon specimens were measured and compared with those predicted by the finite element analysis using the one-parameter plasticity model. The results show that the one-parameter plasticity model is suitable for the analysis of elastic-plastic deformation of AS4/PEEK composite laminates.

  10. Sample size planning for composite reliability coefficients: accuracy in parameter estimation via narrow confidence intervals.

    Science.gov (United States)

    Terry, Leann; Kelley, Ken

    2012-11-01

    Composite measures play an important role in psychology and related disciplines. Composite measures almost always have error. Correspondingly, it is important to understand the reliability of the scores from any particular composite measure. However, the point estimates of the reliability of composite measures are fallible and thus all such point estimates should be accompanied by a confidence interval. When confidence intervals are wide, there is much uncertainty in the population value of the reliability coefficient. Given the importance of reporting confidence intervals for estimates of reliability, coupled with the undesirability of wide confidence intervals, we develop methods that allow researchers to plan sample size in order to obtain narrow confidence intervals for population reliability coefficients. We first discuss composite reliability coefficients and then provide a discussion on confidence interval formation for the corresponding population value. Using the accuracy in parameter estimation approach, we develop two methods to obtain accurate estimates of reliability by planning sample size. The first method provides a way to plan sample size so that the expected confidence interval width for the population reliability coefficient is sufficiently narrow. The second method ensures that the confidence interval width will be sufficiently narrow with some desired degree of assurance (e.g., 99% assurance that the 95% confidence interval for the population reliability coefficient will be less than W units wide). The effectiveness of our methods was verified with Monte Carlo simulation studies. We demonstrate how to easily implement the methods with easy-to-use and freely available software. ©2011 The British Psychological Society.

  11. Sex effect on productive parameters, carcass and body fat composition of two commercial broilers lines

    Directory of Open Access Journals (Sweden)

    S Rondelli

    2003-12-01

    Full Text Available The aim of this work was to evaluate sex effect on behavior of two commercial broilers lines. Productive parameters, carcass composition and yield, amount and quality of fat deposited in the meat and skin and total body fat were studied. A completely randomized design with four treatments (MR-Male Ross, HR-Female Ross, MAF-Male Avian Farm and HAF-Female Avian Farm and eight repetitions of 40 chickens was used. Animals received water and food ad libitum. After 50 days, two birds (a male and a female per repetition were chosen at random and slaughtered for carcass evaluation. Samples of breast, leg, skin and abdominal fats were analyzed to determine the percentage of intramuscular fat, total cholesterol and fatty acid composition. The Ross line showed higher final weight and weight gain, better intake and feed conversion rate. Also, it was observed that females of both lines had similar results in relation to these parameters. Better yield of breast with bone was found in Ross males and females. In relation to legs and thigh, Ross males showed better results and no differences were observed among females of both lines. Males deposited less fat than females. Finally, differences in percentage of intramuscular fat, content of cholesterol in breast with skin, leg with skin and skin, percentage of saturated, mono and polyunsaturated fatty acids were observed between sex and lines.

  12. Influence of process parameters to composite interface organization and performance of liquid/solid bimetal

    International Nuclear Information System (INIS)

    Rong, S F; Zhu, Y C; Wu, Y H; Yang, P H; Duan, X L; Zhou, H T

    2015-01-01

    The liquid-solid composite technique was used to prepare the high carbon high chromium steel (HCHCS) and low alloy steel (LCS) bimetal composite materials by means of insert casting method. The influence of some process parameters such as liquid-solid ratio, preheat temperature, pouring temperature on the interface microstructure and mechanical properties were studied. Interface microstructure and element distribution were analyzed. The results show that the interface microstructure becomes better, and bonding area becomes thicker with the increase of the volume of liquid to solid ratio, preheating temperature and pouring temperature. When the liquid-solid ratio is 8:1, the preheating temperature is 300 °C and the pouring temperature is 1565 °C, a good metallurgical bonding area without any hole can be obtained with the interface combination of diffusion and fusion. The composite interface structure was composed of a core material diffusion layer, a cooling solidification layer, a direction growth layer and some cell particles. The elements of C, Cr and Mn diffuse from the HCHCS side to the alloy steel side. The microhardness increased in the gradient from the LCS side to the HCHCS. The microhardness of the interface is significantly higher than that of LCS. (paper)

  13. Predictive Models for Different Roughness Parameters During Machining Process of Peek Composites Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Mata-Cabrera Francisco

    2013-10-01

    Full Text Available Polyetheretherketone (PEEK composite belongs to a group of high performance thermoplastic polymers and is widely used in structural components. To improve the mechanical and tribological properties, short fibers are added as reinforcement to the material. Due to its functional properties and potential applications, it’s impor- tant to investigate the machinability of non-reinforced PEEK (PEEK, PEEK rein- forced with 30% of carbon fibers (PEEK CF30, and reinforced PEEK with 30% glass fibers (PEEK GF30 to determine the optimal conditions for the manufacture of the parts. The present study establishes the relationship between the cutting con- ditions (cutting speed and feed rate and the roughness (Ra , Rt , Rq , Rp , by develop- ing second order mathematical models. The experiments were planned as per full factorial design of experiments and an analysis of variance has been performed to check the adequacy of the models. These state the adequacy of the derived models to obtain predictions for roughness parameters within ranges of parameters that have been investigated during the experiments. The experimental results show that the most influence of the cutting parameters is the feed rate, furthermore, proved that glass fiber reinforcements produce a worse machinability.

  14. Modeling and Analysis of CNC Milling Process Parameters on Al3030 based Composite

    Science.gov (United States)

    Gupta, Anand; Soni, P. K.; Krishna, C. M.

    2018-04-01

    The machining of Al3030 based composites on Computer Numerical Control (CNC) high speed milling machine have assumed importance because of their wide application in aerospace industries, marine industries and automotive industries etc. Industries mainly focus on surface irregularities; material removal rate (MRR) and tool wear rate (TWR) which usually depends on input process parameters namely cutting speed, feed in mm/min, depth of cut and step over ratio. Many researchers have carried out researches in this area but very few have taken step over ratio or radial depth of cut also as one of the input variables. In this research work, the study of characteristics of Al3030 is carried out at high speed CNC milling machine over the speed range of 3000 to 5000 r.p.m. Step over ratio, depth of cut and feed rate are other input variables taken into consideration in this research work. A total nine experiments are conducted according to Taguchi L9 orthogonal array. The machining is carried out on high speed CNC milling machine using flat end mill of diameter 10mm. Flatness, MRR and TWR are taken as output parameters. Flatness has been measured using portable Coordinate Measuring Machine (CMM). Linear regression models have been developed using Minitab 18 software and result are validated by conducting selected additional set of experiments. Selection of input process parameters in order to get best machining outputs is the key contributions of this research work.

  15. Optimization of Electrochemical Parameters for Landfill Leachate Treatment Using Charcoal Base Metallic Composite Electrode

    International Nuclear Information System (INIS)

    Majd Ahmed Jumaah; Mohamed Rozali Othman

    2015-01-01

    Landfill leachate normally contains organic and inorganic pollutants in high concentrations. Electrochemical oxidation technique is an effective method to treat landfill leachate, have high efficiency in organic pollutants degradation and ammonia removal. In this study, a cost effective charcoal base metallic composite electrode to treat landfill leachate by electrochemical oxidation was fabricated. The effects of operational parameters such as supporting electrolyte, applied voltage and electrolysis time on the removal percentage of Color, COD, NH 3 -N and total-P (PO 4 -3 ) were carried out. The results obtained show that the removal percentage of Color, COD, NH 3 -N and total- P (PO 4 -3 ) are 70, 89, 73 and 80 % respectively. Under the optimum operating condition, sodium chloride concentration of 1.5 % (w/v), applied voltage of 10 V, operating time 180 min and C 60 C G 15 Co 10 - PVC 15 electrode as an anode were used. (author)

  16. Determination of fracture parameters for interface cracks in transverse isotropic magnetoelectroelastic composites

    Directory of Open Access Journals (Sweden)

    Lei Jun

    2015-01-01

    Full Text Available To determine fracture parameters of interfacial cracks in transverse isotropic magnetoelectroelastic composites, a displacement extrapolation formula was derived. The matrix-form formula can be applicable for both material components with arbitrary poling directions. The corresponding explicit expression of this formula was obtained for each poling direction normal to the crack plane. This displacement extrapolation formula is only related to the boundary quantities of the extended crack opening displacements across crack faces, which is convenient for numerical applications, especially for BEM. Meantime, an alternative extrapolation formula based on the path-independent J-integral and displacement ratios was presented which may be more adaptable for any domain-based numerical techniques like FEM. A numerical example was presented to show the correctness of these formulae.

  17. Studies on formability of sintered aluminum composites during hot deformation using strain hardening parameters

    Directory of Open Access Journals (Sweden)

    Sumesh Narayan

    2017-04-01

    Full Text Available Formability is the limit to which a material can be deformed before failure and is upmost importance in powder metallurgy (PM forming process. This is because the presence of porosity in the PM part after the sintering process. In this study two key strain hardening parameters are used to study the workability behavior or determining the failure zone. This can be used for design of PM parts and most importantly the die design as repressing needs to be employed before pores appear as cracks on the free surface. It is nearly impossible to produce defect free parts if this failure occurs. The hot formability behavior of aluminum metal matrix composites (MMC's that is, Al-4TiC, Al-4WC, Al-4Fe3C and Al-4Mo2C (by weight percentage are presented in this paper.

  18. Effect of salinity on growth, biochemical parameters and fatty acid composition in safflower (carthamus tinctorius l.)

    International Nuclear Information System (INIS)

    Javed, S.; Bukhari, S.A.; Mahmood, S.; Iftikhar, T.

    2014-01-01

    The aim of the present project is to investigate the effect of salinity on growth, biochemical parameters and fatty acid composition in six varieties of safflower as well as identification of stress tolerant variety under saline (8 d Sm-1) condition. It was observed that salinity significantly decreased the dry weight and fresh weight of safflower varieties. Nitrate reductase (NRA) and nitrite reductase (NiRA) activities were also reduced in response to salinity in all safflower genotypes but Thori-78 and PI-387820 showed less reduction which could be a useful marker for selecting salt tolerant varieties. Under salinity stress, total free amino acids, reducing, non reducing sugars and total sugars increased in all varieties. Accumulation of sugars and total free amino acids might reflect a salt protective mechanism and could be a useful criterion for selecting salt tolerant variety. Comparison among safflower genotypes indicated that Thori-78 and PI-387820 performed better than the others and successful in maintaining higher NRA, NiRA and other metabolites thus were tolerant to salinity. Differential effect upon fatty acid synthesis was observed by different varieties under salinity stress but PI-170274 and PI-387821 varieties better maintained their fatty acid composition. It can be concluded from present studies that biochemical markers can be used to select salinity tolerant safflower varieties. (author)

  19. A compositional look at the human gastrointestinal microbiome and immune activation parameters in HIV infected subjects.

    Directory of Open Access Journals (Sweden)

    Ece A Mutlu

    2014-02-01

    Full Text Available HIV progression is characterized by immune activation and microbial translocation. One factor that may be contributing to HIV progression could be a dysbiotic microbiome. We therefore hypothesized that the GI mucosal microbiome is altered in HIV patients and this alteration correlates with immune activation in HIV. 121 specimens were collected from 21 HIV positive and 22 control human subjects during colonoscopy. The composition of the lower gastrointestinal tract mucosal and luminal bacterial microbiome was characterized using 16S rDNA pyrosequencing and was correlated to clinical parameters as well as immune activation and circulating bacterial products in HIV patients on ART. The composition of the HIV microbiome was significantly different than that of controls; it was less diverse in the right colon and terminal ileum, and was characterized by loss of bacterial taxa that are typically considered commensals. In HIV samples, there was a gain of some pathogenic bacterial taxa. This is the first report characterizing the terminal ileal and colonic mucosal microbiome in HIV patients with next generation sequencing. Limitations include use of HIV-infected subjects on HAART therapy.

  20. Study on the influence of design parameters on the damping property of glass fiber reinforced epoxy composite

    Science.gov (United States)

    Bhattacharjee, A.; Nanda, B. K.

    2018-04-01

    Fiber reinforced composites are widely used in industrial applications due to their high strength, light weight and ease in manufacturing. In applications such as automotive, aerospace and structural parts, the components are subjected to unwanted vibrations which reduce their service life, accuracy as well as increases noise. Therefore, it is essential to avoid the detrimental effects of vibrations by enhancing their damping characteristics. The current research deals with estimating the damping properties of Glass fiber reinforced epoxy (GFRE) composites. Processing of the GFRE composites is carried out using hand-lay technique. Various design parameters such as number of glass fiber layers, orientation of fibers and weight ratio are varied while manufacturing GFRE composites. The effects of variation of these design parameters on damping property of GFRE composites are studied extensively.

  1. Determination of Critical Parameters of Carbon Dioxide+ Butyraldehyde System with Different Compositions

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jing-chang; GAO Xi-xin; CAO Wei-liang

    2005-01-01

    Supercritical carbon dioxide( SC-CO2 ) is considered in green chemistry as a substitute for conventional solvents in chemical reactions due to its environmentally benign character. Recently we have reported the homogeneous hydroformylation of propylene in supercritical carbon dioxide( SC-CO2 ), which is an example of this kind of application of carbon dioxide. The determination for the critical parameters of carbon dioxide + butyraldehyde mixtures is necessary for this reaction design which is the focus of the present paper. The critical parameters of the binary systems were determined via the static visual method at a constant volume with the molar fraction of butyraldehyde ranging from 1.0%to 2. 2% and the pressure ranging from 5 to 10 MPa. The experimental results show that the critical pressure and temperature increased with increasing the molar fraction of butyraldehyde. The bubble(dew) temperatures and the bubble (dew) pressures for the binary systems were also determined experimentally. The p-T Figures at different compositions of the binary systems were described. In addition, the critical compressibility factors Zc of the binary systems at different concentrations of n-butyraldehyde were calculated. It was found that the critical compressibility factor values of the binary systems decreased with increasing the molar fraction of n-butyraldehyde in the experimental range.

  2. External Thermal Insulation Composite Systems: Critical Parameters for Surface Hygrothermal Behaviour

    Directory of Open Access Journals (Sweden)

    Eva Barreira

    2014-01-01

    Full Text Available External Thermal Insulation Composite Systems (ETICS are often used in Europe. Despite its thermal advantages, low cost, and ease of application, this system has serious problems of biological growth causing the cladding defacement. Recent studies pointed that biological growth is due to high values of surface moisture content, which mostly results from the combined effect of exterior surface condensation, wind-driven rain, and drying process. Based on numerical simulation, this paper points the most critical parameters involved in hygrothermal behaviour of ETICS, considering the influence of thermal and hygric properties of the external rendering, the effect of the characteristics of the façade, and the consequences of the exterior and interior climate on exterior surface condensation, wind-driven rain, and drying process. The model used was previously validated by comparison with the results of an “in situ” campaign. The results of the sensitivity analyses show that relative humidity and temperature of the exterior air, atmospheric radiation, and emissivity of the exterior rendering are the parameters that most influence exterior surface condensation. Wind-driven rain depends mostly on horizontal rain, building’s height, wind velocity, and orientation. The drying capacity is influenced by short-wave absorbance, incident solar radiation, and orientation.

  3. Assessment of the Body Composition and Parameters of the Cardiovascular Risk in Juvenile Idiopathic Arthritis

    Directory of Open Access Journals (Sweden)

    Ewa Jednacz

    2015-01-01

    Full Text Available The study was aimed to evaluate cardiovascular risk parameters, body mass index (BMI centiles for sex and age, and body fat percentage using the electric bioimpedance method in children with juvenile idiopathic arthritis (JIA. 30 children with JIA participated in the study. A control group included 20 children. Patients were well matched for the age and sex. The body mass and body fat percentage were determined using the segmental body composition analyser; the BMI centiles were determined. All patients had the following parameters determined: lipid profile, hsCRP, homocysteine, and IL-6. The intima media thickness (IMT was measured. Patients with JIA had significantly lower body weight, BMI, and the BMI centile compared to the control group. The IL-6 levels were significantly higher in patients with JIA compared to the control group. There were no differences between two groups with regard to the lipid profile, % content of the fat tissue, homocysteine levels, hsCRP, and IMT. Further studies are necessary to search for reasons for lower BMI and BMI centile in children with JIA and to attempt to answer the question of whether lower BMI increases the cardiovascular risk in these patients, similarly as in patients with rheumatoid arthritis (RA.

  4. Effect of Processing Parameters on Reliability of VARTM/SCRIMP Composite Panels - Phase 1

    National Research Council Canada - National Science Library

    Dagher, Habib J; Lopez-Anido, Roberto; Thompson, Larry; El-Chiti, Fadi; Fayad, Ghassan; Berube, Keith

    2007-01-01

    .... The structural risks associated with new FRP composite ship structures can be mitigated by characterizing the variability of composite material properties thus ensuring acceptable levels of safety...

  5. The Comparison Analysis of the Main Chemical Composition Parameters of Wild Boar Meat and Pork

    Directory of Open Access Journals (Sweden)

    Erika Bodnárné Skobrák

    2011-05-01

    Full Text Available The chemical composition of wild boar meat from wild boar parks with various habitats and different feeding facilities was analysed. Samples were collected from m. serratus anterior – during the winter hunting period. The protein, the total fat, the saturated and unsaturated fatty acid content were measured and also and those elements which have great importance on human alimentation. The results were compared with other author’s data of the same parameters of pork. The aim of the study was to compare the effect of different feeding systems on the ingredients of wild boar meat, and the accidental analogy with the ingredients of pork. There was no difference in protein content. The value of miristic acid (C14:0 in the samples of extensively and intensively fed group was more favourable than that of pork. Pork contains more MUFA (palmitoleic acid – C16:1. The semi-intensively fed wild boar’s meat and pork contained linoleic acid (C18:3 n3 almost on the same level. The greatest difference was detected in the level of arachidonic acid (C20:4 n6. The samples from all wild boar groups contained more of this fatty acid than it was published about domestic pigs. Out of the microelements, the iodine and zinc had higher value in wild boar meat than in pork.

  6. Effect of dietary lipid levels on body compositions, digestive ability and antioxidant parameters of common carp

    Science.gov (United States)

    Sun, Jinhui; Fan, Ze; Chen, Chunxiu; Li, Jinghui; Cheng, Zhenyan; Li, Yang; Qiao, Xiuting

    2017-11-01

    This study was designed to evaluate the effect of dietary lipid level on body composition, and digestive ability of common carp with initial average weight (36.12 ± 1.18)g. Five experimental diets with increasing lipid levels of 2.1%, 4.0%, 5.8%, 7.6%, 9.4% were fed to triplicate groups of fish for 9 weeks. The results showed that lipid content of whole body and muscle increased in parallel with the increase of dietary lipid levels. Protein content of muscle decreased with the increase of dietary lipid levels, and the lowest muscle protein content was observed in fish fed 9.4% lipid diet. Lipaseactivity was significantly affected by dietary lipid levels in hepatopancreas andintestine (P fish fed at 5.8% lipid level group was significantly higher than others inhepatopancreas (P 0.05). The results suggested that the most excellentdigestive ability and antioxidant parameters were obtained at 7.6% lipid level group.

  7. Effect of sputtering parameters and substrate composition on the structure of tantalum thin films

    Energy Technology Data Exchange (ETDEWEB)

    Hallmann, Lubica, E-mail: lubica.hallmann@zzm.uzh.c [Clinic of Fixed and Removable Prosthodontics and Dental Material Science, Center of Dental Medicine, University of Zürich (Switzerland); Ulmer, Peter [Institute of Geochemistry and Petrology, ETH Zürich (Switzerland)

    2013-10-01

    The crystallographic properties of tantalum films deposited as a bioactive coating on Co–Cr–Mo and Ti–Al–Nb alloys have been investigated. The desired tough and ductile alpha phase of tantalum has been obtained by DC magnetron sputtering on Co–Cr–Mo and Ti–Al–Nb substrates. The thickness of the tantalum layer was between 20 and 600 nm. The crystallographic structure of tantalum thin film was dependent on the sputtering parameters such as DC power, bias voltage and gas impurities. Oxygen is an important factor for the stabilization of the tantalum alpha phase on Co–Cr–Mo substrate. The crystallographic structure and texture of tantalum thin films was found to be additionally dependent on the substrate composition. For Ti–Al–Nb substrate, oxygen content was not an important factor for the stabilization of the alpha phase. The observed shift of X-ray diffraction peaks to lower 2(θ) is an indication of stress evolving during the sputtering process and was dependent on bias voltage and oxygen content of the carrier gas.

  8. Precipitation, groundwater and surface waters. Control of climate parameters on their isotopic composition and their utilization as palaeoclimatological tools

    International Nuclear Information System (INIS)

    Gat, J.R.

    1983-01-01

    The isotopic composition of precipitation is correlated with climatic parameters such as mean temperature and humidity both in the source areas of the atmospheric moisture and along the storm trajectories. However, additional meteorological variables such as seasonal distributions of rainfall, convection patterns in the cloud and intensity, duration and intermittency of rain influence the isotopic composition. It is shown in this context that the isotopic composition of Negev and Sinai palaeowaters is consistent with the notion of summer rains in this area arising from Atlantic-based storm centres. (author)

  9. Influence of extrusion parameters on sic distribution and properties of AA6061/SiC composites produced by kobo method

    Energy Technology Data Exchange (ETDEWEB)

    WoĨniak, Jarosáaw; Kostecki, Marek; Broniszewski, Kamil; Olszyna, Andrzej [Faculty of Material Science and Engineering, Warsaw University of Technology, Warsaw (Poland); Bochniak, Wáodzimierz [Faculty of Non-Ferrous Metals, AGH University of Science and Technology, Cracow (Poland)

    2013-07-01

    The influence of extrusion parameters on reinforcements distribution and properties of AA6061+x% vol. SiC p (x=0; 2.5; 5; 7.5; 10) composites was discussed in this paper The averages size of AA6061 and SiC particles were 10.6 μ m and 0.42 μ m, respectively. The composites were consolidated via powder metallurgy processing (without the sintering) and extruded by KoBo method. The microstructure was examined on each steps of production. High values of density for all produced composites were achieved. Additionally, hardness and Young’s modulus were investigated. The best reinforcement distribution and mechanical properties were obtained for composites extruded with the highest extrusion ratio. Key words: aluminum alloy, extrusion, aged hardening, metal matrix composites, microstructure.

  10. Correlation between some technological parameters and properties of composite material based on recycled tires and polymer binder

    Science.gov (United States)

    Plesuma, Renate; Malers, Laimonis

    2015-04-01

    The present article is dedicated to the determination of a possible connection between the composition, specific properties of the composite material and molding pressure as an important technological parameter. Apparent density, Shore C hardness, compressive modulus of elasticity and compressive stress at 10% deformation was determined for composite material samples. Definite formation conditions - varying molding pressure conditions at ambient temperature and corresponding relative air humiditywere realized. The results obtained showed a significant effect of molding pressure on the apparent density, mechanical properties of composite material as well as on the compressive stress change at a cyclic mode of loading. Some general regularities were determined - mechanical properties of the composite material, as well as values of Shore C hardness increases with an increase of molding pressure.

  11. Damage characteristics in 3D stitched composites with various stitch parameters under in-plane tension

    KAUST Repository

    Yudhanto, Arief; Lubineau, Gilles; Ventura, Isaac Aguilar; Watanabe, Naoyuki; Iwahori, Yutaka; Hoshi, Hikaru

    2015-01-01

    Three-dimensional (3D) reinforcement by stitching is effective in improving the impact resistance of composites. Stitching, however, adversely affects the composite's in-plane mechanical responses, and alters its damage mechanisms due to stitch

  12. Nuchal Skinfold Thickness: A Novel Parameter for Assessment of Body Composition in Childhood Craniopharyngioma

    Science.gov (United States)

    Sterkenburg, Anthe S.; Hoffmann, Anika; Reichel, Julia; Lohle, Kristin; Eveslage, Maria; Warmuth-Metz, Monika

    2016-01-01

    Context: Hypothalamic obesity, cardiovascular disease (CVD), and relapse/progression have a major impact on prognosis in childhood-onset craniopharyngioma (CP). We analyzed nuchal skinfold thickness (NST) on magnetic resonance imaging performed for follow-up monitoring as a novel parameter for body composition (BC) and CVD in CP. Objective: The objective of the study was to identify the association of NST with body mass index (BMI), waist to height ratio (WHtR), functional capacity, and blood pressure (BP) in CP and controls. Design: This was a cross-sectional and longitudinal prospective study in CP patients. Setting: The study was conducted at HIT-Endo, KRANIOPHARYNGEOM 2000/2007. Patients: Participants included 94 CP patients and 75 controls. Interventions: There were no interventions. Main Outcome Measures: Association of NST with BC and BP in 43 CP and 43 controls was measured. Results: NST correlated with BMI SD score (SDS; r = 0.78; P < .001; n = 169) and WHtR (r = 0.85; P < .001; n = 86) in the total cohort and CP patients (NST-BMI SDS: r = 0.77, P < .001, n = 94); NST-WHtR: r = 0.835, P < .001, n=43) and controls (NST-BMI SDS: r = 0.792, P < .001, n = 75; NST-WHtR: r = 0.671, P < .001, n = 43). In CP, systolic BP correlated with NST (r = 0.575, P < .001), BMI SDS (r = 0.434, P = .004), and WHtR (r = 0.386, P = .011). Similar results were observed for diastolic BP in CP. In multivariate analyses, NST had a predictive value for hypertension in postpubertal CP and controls (odds ratio 6.98, 95% confidence interval [1.65, 29.5], P = .008). During a longitudinal follow-up, changes in NST correlated with changes in BMI SDS (P < .001) and WHtR (P = .01) but not with changes in BP and functional capacity. Conclusions: Because monitoring of magnetic resonance imaging and BC is essential for follow-up in CP, NST could serve as a novel and clinically relevant parameter for longitudinal assessment of BC and CVD risk in CP. PMID:27680877

  13. Crystal nucleation in binary hard-sphere mixtures: the effect of order parameter on the cluster composition

    NARCIS (Netherlands)

    Ni, R.; Smallenburg, F.; Filion, L.C.; Dijkstra, M.

    2011-01-01

    We study crystal nucleation in a binary mixture of hard spheres and investigate the composition and size of the (non)critical clusters using Monte Carlo simulations. In order to study nucleation of a crystal phase in computer simulations, a one-dimensional order parameter is usually defined to

  14. Study of Body Composition and Metabolic Parameters in HIV-1 Male Patients

    Directory of Open Access Journals (Sweden)

    Gurudath Gundurao Sreekantamurthy

    2014-01-01

    Full Text Available Background. HIV patients on highly active antiretroviral therapy (HAART containing protease inhibitors (PIs had been often associated with lipodystrophy. However, there are only few studies on association of nucleoside and nonnucleoside reverse transcriptase inhibitors (NRTI and NNRTI with lipodystrophy. Study Design. One hundred and one HIV male patients were categorised into ART naïve (n=22, zidovudine (n=22, stavudine (n=18, tenofovir (n=15, and PIs (n=24 based HAART. Their clinicoepidemiological data had been entered in preformed pro forma. The body composition, using TANITA machine and metabolic parameters like lipid profile, blood sugars was analysed. Results. Clinically, lipoatrophy of face was most prevalent in HIV patients on stavudine (15 patients, 83.3% and PIs (20 patients, 83.3% based HAART. The mean BMI among study population was in normal range. Excess visceral fat was most prevalent among patients on PIs, 4 patients (16.7%. The waist-hip ratio was significantly higher in PIs (P=0.01 based HAART. There was no significant difference among different study populations in terms of BMI (P=0.917, body water (P=0.318, body fat (P=0.172, bone mass (P=0.200, and muscle mass (P=0.070. Hypertriglyceridiemia was found in stavudine, tenofovir, and protease inhibitors regimens. Low levels of high density lipoprotein (HDL was found zidovudine, stavudine, and PIs regimens. Fasting and postprandial hyperglycaemia was found PIs and impaired glucose tolerance in stavudine regimen. Conclusion. Patients on PIs were associated with truncal obesity and lipoatrophy of face, along with dyslipidemia and hyperglycaemia. Stavudine based regimen is associated with hypertriglyceridiemia and low HDL along with lipoatrophy of face.

  15. The effects of Ramadan fasting and physical activity on body composition and hematological biochemical parameters

    Directory of Open Access Journals (Sweden)

    Seyyed Reza Attarzadeh Hosseini

    2014-09-01

    Full Text Available Introduction: Hunger and reduction in regular energy intake can lead to a number of problems based on their intensity. For instance, low energy level can cause blood cell production to decline or it may pose a higher risk of anemia. It can also weaken the immune system and platelet aggregation or negatively affect clot formation. This study aimed to have a closer look at fasting and regular physical activity and their impacts on body composition and blood hematological-biochemical parameters among professional wrestlers. Method: In this semi-experimental study, 9 subjects were selected by convenience sampling. The selected training program included participation in this exerciseprogram, 90 min per session, 6 times per week for a period of one month. Blood samples were obtained four times: before the start of Ramadan, 2 weeks after the start, during the last week and 2 weeks after the end of Ramadan. To make intra-group comparison, repeated measure analysis of variance was used. For all statistical comparisons, the level of significance was considered at PResults: Body weight and red blood cell count (RBC dropped significantly at the end of Ramadan (Respectively P= 0.001 and P=0.034. However, the number of white blood cells (WBC and circulating platelets (PLT significantly increased during fasting (Respectively P= 0.048 and P=0.042. As a matter of fact, PLT and WBC were the only factors which dramatically increased during fasting. Intra-group variations of tetracycline (TC, low-density lipoprotein (LDL, LDL: high-density lipoprotein (HDL, triglyceride (TG: HDL and TC: HDL reduced at the end of Ramadan. However, HDL levels ​​drastically increased during fasting (P≤0.05. Conclusion: Based on the results of the research, despite being a regular activity and fasting has beneficial effects on lipid profile in athletes, however, they can with tangible changes in hematological factors may lead to weaken the immune system of athletes.

  16. Fast and simple method for prediction of the micromechanical parameters and macromechanical properties of composite materials

    OpenAIRE

    Delgado Aguilar, Marc; Julián Pérez, Fernando; Pèlach Serra, Maria Àngels; Espinach Orús, Xavier; Méndez González, José Alberto; Mutjé Pujol, Pere

    2016-01-01

    The method described in the present work was assessed through the production of composite materials made of polypropylene reinforced with chemical thermomechanical pulp of hemp core fibers. Composite materials were obtained by extrusion and injection molding, and by the addition of a coupling agent to ensure a good interphase between fiber and matrix. In all cases, the composite materials were considered as semi-aligned reinforced. Tensile strength was selected as a representative...

  17. The Influence of Pressure Die Casting Parameters on the Castability of AlSi11-SiCp Composites

    Directory of Open Access Journals (Sweden)

    Konopka Z.

    2015-03-01

    Full Text Available The paper presents the method of preparing a composite slurry composed of AlSi11 alloy matrix and 10 vol.% of SiC particles, as well as the method of its high-pressure die casting and the measurement results concerning the castability of the obtained composite. Composite castings were produced at various values of the piston velocity in the second stage of injection, diverse intensification pressure values, and various injection gate width values. There were found the regression equations describing the change of castability of the examined composite as a function of pressure die casting process parameters. The conclusion gives the analysis and the interpretation of the obtained results.

  18. Effect of Material Parameters on Mechanical Properties of Biodegradable Polymers/Nanofibrillated Cellulose (NFC) Nano Composites

    Science.gov (United States)

    Yottha Srithep; Ronald Sabo; Craig Clemons; Lih-Sheng Turng; Srikanth Pilla; Jun Peng

    2012-01-01

    Using natural cellulosic fibers as fillers for biodegradable polymers can result in fully biodegradable composites. Biodegradable composites were prepared using nanofibrillated cellulose (NFC) as the reinforcement and poly (3-hydroxybutyrate-co-3-hydroxyvalerate, PHBV) as the polymer matrix. The objective of this study was to determine how various additives (i.e.,...

  19. On the Effect of Unit-Cell Parameters in Predicting the Elastic Response of Wood-Plastic Composites

    Directory of Open Access Journals (Sweden)

    Fatemeh Alavi

    2013-01-01

    Full Text Available This paper presents a study on the effect of unit-cell geometrical parameters in predicting elastic properties of a typical wood plastic composite (WPC. The ultimate goal was obtaining the optimal values of representative volume element (RVE parameters to accurately predict the mechanical behavior of the WPC. For each unit cell, defined by a given combination of the above geometrical parameters, finite element simulation in ABAQUS was carried out, and the corresponding stress-strain curve was obtained. A uniaxial test according to ASTM D638-02a type V was performed on the composite specimen. Modulus of elasticity was determined using hyperbolic tangent function, and the results were compared to the sets of finite element analyses. Main effects of RVE parameters and their interactions were demonstrated and discussed, specially regarding the inclusion of two adjacent wood particles within one unit cell of the material. Regression analysis was performed to mathematically model the RVE parameter effects and their interactions over the modulus of elasticity response. The model was finally employed in an optimization analysis to arrive at an optimal set of RVE parameters that minimizes the difference between the predicted and experimental moduli of elasticity.

  20. Composition and structure variation for magnetron sputtered tantalum oxynitride thin films, as function of deposition parameters

    Energy Technology Data Exchange (ETDEWEB)

    Cristea, D.; Pătru, M.; Crisan, A.; Munteanu, D. [Department of Materials Science, Transilvania University, 500036 Brasov (Romania); Crăciun, D. [Laser Department, National Institute for Laser, Plasma, and Radiation Physics, Magurele (Romania); Barradas, N.P. [Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, E.N. 10 ao km 139,7, 2695-066 Bobadela LRS (Portugal); Alves, E. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, E.N. 10 ao km 139,7, 2695-066 Bobadela LRS (Portugal); Apreutesei, M. [Université de Lyon, Institut des Nanotechnologies de Lyon INL-UMR 5270, CNRS, Ecole Centrale de Lyon, Ecully F-69134 (France); MATEIS Laboratory-INSA de Lyon, Bât. B. Pascal, 7 Avenue Jean Capelle, 69621 Villeurbanne Cedex (France); Moura, C. [Center of Physics, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Cunha, L., E-mail: lcunha@fisica.uminho.pt [Center of Physics, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal)

    2015-12-15

    Highlights: • Structural evolution from β-Ta, to fcc-Ta(O,N), to amorphous Ta{sub 2}O{sub 5} with increasing P(N{sub 2} + O{sub 2}). • The substrate bias influences the N content, but does not influence the O content of the films. • The structural features of the films appear at lower P(N{sub 2} + O{sub 2}) when produced with grounded substrate. - Abstract: Tantalum oxynitride thin films were produced by magnetron sputtering. The films were deposited using a pure Ta target and a working atmosphere with a constant N{sub 2}/O{sub 2} ratio. The choice of this constant ratio limits the study concerning the influence of each reactive gas, but allows a deeper understanding of the aspects related to the affinity of Ta to the non-metallic elements and it is economically advantageous. This work begins by analysing the data obtained directly from the film deposition stage, followed by the analysis of the morphology, composition and structure. For a better understanding regarding the influence of the deposition parameters, the analyses are presented by using the following criterion: the films were divided into two sets, one of them produced with grounded substrate holder and the other with a polarization of −50 V. Each one of these sets was produced with different partial pressure of the reactive gases P(N{sub 2} + O{sub 2}). All the films exhibited a O/N ratio higher than the N/O ratio in the deposition chamber atmosphere. In the case of the films produced with grounded substrate holder, a strong increase of the O content is observed, associated to the strong decrease of the N content, when P(N{sub 2} + O{sub 2}) is higher than 0.13 Pa. The higher Ta affinity for O strongly influences the structural evolution of the films. Grazing incidence X-ray diffraction showed that the lower partial pressure films were crystalline, while X-ray reflectivity studies found out that the density of the films depended on the deposition conditions: the higher the gas pressure, the

  1. The Effect of Fracture Filler Composition on the Parameters of Shear Deformation Regime

    Science.gov (United States)

    Pavlov, D.; Ostapchuk, A.; Batuhtin, I.

    2015-12-01

    Geomechanical models of different slip mode nucleation and transformation can be developed basing on laboratory experiments, in which regularities of shear deformation of gouge-filled faults are studied. It's known that the spectrum of possible slip modes is defined by both macroscopic deformation characteristics of the fault and mesoscale structure of fault filler. Small variations of structural parameters of the filler may lead to a radical change of slip mode [1, 2]. This study presents results of laboratory experiments investigating regularities of shear deformation of discontinuities filled with multicomponent granular material. Qualitative correspondence between experimental results and natural phenomena is detected. The experiments were carried out in the classical "slider model" statement. A granite block slides under shear load on a granite substrate. The contact gap between rough surfaces was filled with a discrete material, which simulated the principal slip zone of a fault. The filler components were quartz sand, salt, glass beads, granite crumb, corundum, clay and pyrophyllite. An entire spectrum of possible slip modes was obtained - from stable slip to slow-slip events and to regular stick-slip with various coseismic displacements realized per one act of instability. Mixing several components in different proportions, it became possible to trace the gradual transition from stable slip to regular stick-slip, from slow-slip events to fast-slip events. Depending on specific filler component content, increasing the portion of one of the components may lead to both a linear and a non-linear change of slip event moment (a laboratory equivalent of the seismic moment). For different filler compositions durations of equal-moment events may differ by more than two orders of magnitude. The findings can be very useful for developing geomechnical models of nucleation and transformation of different slip modes observed at natural faults. The work was supported by

  2. Multi-objective Optimization of Friction Welding Process Parameters using Grey Relational Analysis for Joining Aluminium Metal Matrix Composite

    Directory of Open Access Journals (Sweden)

    Sreenivasan KONGANAPURAM SUNDARARAJAN

    2018-05-01

    Full Text Available Aluminium metal matrix composites has gained importance in recent time because of its improved mechanical and metallurgical properties. The welding of aluminium metal matrix composites using conventional welding process has got many demerits so in order to overcome them a solid state welding process is to be employed. To achieve a good strength weld in the aluminium metal matrix composite bars an efficient and most preferred technique is friction welding. In this work the aluminium metal matrix composite AA7075 + 10 % vol SiC-T6 is selected and friction welded. The combination of friction welding process parameters such as spindle speed, friction pressure, upset pressure and burn-off- length for joining the AA7075 + 10 % vol SiCP-T6 metal matrix composite bars are selected by Taguchi’s design of experiment. The optimum friction welding parameters were determined for achieving improved ultimate tensile strength and the hardness using grey relational analysis. A combined grey relational grade is found from the determined grey relational coefficient of the output responses and the optimum friction welding process parameters were obtained as spindle speed – 1200 rpm, friction pressure – 100 MPa, upset pressure – 250 MPa, Burn-off-Length – 2 mm. Analysis of variance (ANOVA performed shows that the friction pressure is the most significant friction welding parameter that influences the both the ultimate tensile strength and hardness of friction welded AA7075 + 10 % volSiCP-T6 joints. The fractured surface under microstructure study also revealed good compliance with the grey relational grade result. DOI: http://dx.doi.org/10.5755/j01.ms.24.2.17725

  3. X-ray fluorescence determination of composition of the high temperature superconductors by the fundamental parameter method

    International Nuclear Information System (INIS)

    Mao Zhenwei; Shi Lei; Chen Shuyu; Zhou Guien

    2001-01-01

    Y, Pr, Ba and Cu compositions of the series of the Y 1-x Pr x Ba 2 Cu 3 O y samples have been determined by using X-ray fluorescence (XRF) fundamental parameter method in a non-destruction state. The composition is given by an atomic fraction. The determined compositions of the samples show a difference from their nominal compositions. One of the reasons why the exact shape of T c vs x varies is different from group to group, as reported, is the difference of the real and the nominal compositions. The relation of T c vs x is not a simple quadric curve. The results agree well with those obtained by the inductively coupled plasma atomic emission spectrometer (ICP-AES), which indicates that the method is appropriate for the determination of the compositions of the high temperature superconductors. In addition, the influence of oxygen on analytical elements is discussed. The fraction of the matrix total mass absorption, which is associated with oxygen for each analytical line, is less than 3.41%

  4. Effect of Processing Parameters on Reliability of VARTM/SCRIMP Composite Panels - Phase 1

    Science.gov (United States)

    2007-07-01

    Finite Element Modeling of Marine Grade Composites. Civil and Enviromental Engineering Department. Orono, University of Maine. Frangopol, D. M. and S...student t-test and a simple percent difference of the means calculation for future interpretations. Typically in engineering practice the practical...environmentally controlled test lab, at the Advanced Engineered Wood Composites (AEWC) Center, at the University of Maine. The rate of crosshead

  5. Determination of lattice parameters, strain state and composition in semipolar III-nitrides using high resolution X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Frentrup, Martin, E-mail: frentrup@physik.tu-berlin.de; Wernicke, Tim; Stellmach, Joachim; Kneissl, Michael [Institute of Solid State Physics, Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin (Germany); Hatui, Nirupam; Bhattacharya, Arnab [Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India)

    2013-12-07

    In group-III-nitride heterostructures with semipolar or nonpolar crystal orientation, anisotropic lattice and thermal mismatch with the buffer or substrate lead to a complex distortion of the unit cells, e.g., by shearing of the lattice. This makes an accurate determination of lattice parameters, composition, and strain state under assumption of the hexagonal symmetry impossible. In this work, we present a procedure to accurately determine the lattice constants, strain state, and composition of semipolar heterostructures using high resolution X-ray diffraction. An analysis of the unit cell distortion shows that four independent lattice parameters are sufficient to describe this distortion. Assuming only small deviations from an ideal hexagonal structure, a linear expression for the interplanar distances d{sub hkl} is derived. It is used to determine the lattice parameters from high resolution X-ray diffraction 2ϑ-ω-scans of multiple on- and off-axis reflections via a weighted least-square fit. The strain and composition of ternary alloys are then evaluated by transforming the elastic parameters (using Hooke's law) from the natural crystal-fixed coordinate system to a layer-based system, given by the in-plane directions and the growth direction. We illustrate our procedure taking an example of (112{sup ¯}2) Al{sub κ}Ga{sub 1−κ}N epilayers with Al-contents over the entire composition range. We separately identify the in-plane and out-of-plane strains and discuss origins for the observed anisotropy.

  6. Computer modelling system of the chemical composition and treatment parameters influence on mechanical properties of structural steels

    OpenAIRE

    L.A. Dobrzański; R. Honysz

    2009-01-01

    Purpose: This paper presents Neuro-Lab. It is an authorship programme, which use algorithms of artificial intelligence for structural steels mechanical properties estimation.Design/methodology/approach: On the basis of chemical composition, parameters of heat and mechanical treatment and elements of geometrical shape and size this programme has the ability to calculate the mechanical properties of examined steel and introduce them as raw numeric data or in graphic as influence charts. Possibl...

  7. [Energy dispersive spectrum analysis of surface compositions of selective laser melting cobalt-chromium alloy fabricated by different processing parameters].

    Science.gov (United States)

    Qian, Liang; Zeng, Li; Wei, Bin; Gong, Yao

    2015-06-01

    To fabricate selective laser melting cobalt-chromium alloy samples by different processing parameters, and to analyze the changes of energy dispersive spectrum(EDS) on their surface. Nine groups were set up by orthogonal experimental design according to different laser powers,scanning speeds and powder feeding rates(laser power:2500-3000 W, scanning speed: 5-15 mm/s, powder feeding rate: 3-6 r/min). Three cylinder specimens(10 mm in diameter and 3 mm in thickness) were fabricated in each group through Rofin DL 035Q laser cladding system using cobalt-chromium alloy powders which were developed independently by our group.Their surface compositions were then measured by EDS analysis. Results of EDS analysis of the 9 groups fabricated by different processing parameters(Co:62.98%-67.13%,Cr:25.56%-28.50%,Si:0.49%-1.23%) were obtained. They were similar to the compositions of cobalt-chromium alloy used in dental practice. According to EDS results, the surface compositions of the selective laser melting cobalt-chromium alloy samples are stable and controllable, which help us gain a preliminary sight into the range of SLM processing parameters. Supported by "973" Program (2012CB910401) and Research Fund of Science and Technology Committee of Shanghai Municipality (12441903001 and 13140902701).

  8. Optimization of Process Parameters During Drilling of Glass-Fiber Polyester Reinforced Composites Using DOE and ANOVA

    Directory of Open Access Journals (Sweden)

    N.S. Mohan

    2010-09-01

    Full Text Available Polymer-based composite material possesses superior properties such as high strength-to-weight ratio, stiffness-to-weight ratio and good corrosive resistance and therefore, is attractive for high performance applications such as in aerospace, defense and sport goods industries. Drilling is one of the indispensable methods for building products with composite panels. Surface quality and dimensional accuracy play an important role in the performance of a machined component. In machining processes, however, the quality of the component is greatly influenced by the cutting conditions, tool geometry, tool material, machining process, chip formation, work piece material, tool wear and vibration during cutting. Drilling tests were conducted on glass fiber reinforced plastic composite [GFRP] laminates using an instrumented CNC milling center. A series of experiments are conducted using TRIAC VMC CNC machining center to correlate the cutting parameters and material parameters on the cutting thrust, torque and surface roughness. The measured results were collected and analyzed with the help of the commercial software packages MINITAB14 and Taly Profile. The surface roughness of the drilled holes was measured using Rank Taylor Hobson Surtronic 3+ instrument. The method could be useful in predicting thrust, torque and surface roughness parameters as a function of process variables. The main objective is to optimize the process parameters to achieve low cutting thrust, torque and good surface roughness. From the analysis it is evident that among all the significant parameters, speed and drill size have significant influence cutting thrust and drill size and specimen thickness on the torque and surface roughness. It was also found that feed rate does not have significant influence on the characteristic output of the drilling process.

  9. Effect of Stress Conditions on Body Composition Parameters of Farmed Rohu (Labeo rohita)

    DEFF Research Database (Denmark)

    Shah, Syed Qaswar Ali; Hussain, Muhammad Zubair; Asif Ali, Muhammad

    2017-01-01

    Various stressors affect the body composition of fish. The current study was undertaken to investigate the effect of stress conditions on the body composition of farmed Labeo rohita. Sixty fingerlings were subjected to experimentation in aquaria after being acclimatized. The specimens were divided...... into control, starvation stress and double stress (pH 8 and starvation) groups with 20 individuals in each group. Fish samples for the estimation of body composition were taken after 12 days, 24 days, 36 days and 48 days. Standard procedures and protocols were used for analysis. There was a trend of gradual...... increase in ash contents (% dry body weight) in starvation and double stress group with increase in number of days. However, fat contents (% dry body weight) considerably decreased and protein contents remained unchanged. The inter-comparison of three groups showed that there was significant effect...

  10. Determination of Fracture Parameters for Multiple Cracks of Laminated Composite Finite Plate

    Science.gov (United States)

    Srivastava, Amit Kumar; Arora, P. K.; Srivastava, Sharad Chandra; Kumar, Harish; Lohumi, M. K.

    2018-04-01

    A predictive method for estimation of stress state at zone of crack tip and assessment of remaining component lifetime depend on the stress intensity factor (SIF). This paper discusses the numerical approach for prediction of first ply failure load (FL), progressive failure load, SIF and critical SIF for multiple cracks configurations of laminated composite finite plate using finite element method (FEM). The Hashin and Chang failure criterion are incorporated in ABAQUS using subroutine approach user defined field variables (USDFLD) for prediction of progressive fracture response of laminated composite finite plate, which is not directly available in the software. A tensile experiment on laminated composite finite plate with stress concentration is performed to validate the numerically predicted subroutine results, shows excellent agreement. The typical results are presented to examine effect of changing the crack tip distance (S), crack offset distance (H), and stacking fiber angle (θ) on FL, and SIF .

  11. Optimization of the tape placement process parameters for carbon–PPS composites

    NARCIS (Netherlands)

    Grouve, Wouter Johannes Bernardus; Warnet, Laurent; Rietman, B.; Visser, Roy; Akkerman, Remko

    2013-01-01

    The interrelation between process parameters, material properties and interlaminar bond strength is investigated for the laser assisted tape placement process. Unidirectionally carbon reinforced poly(phenylene sulfide) (PPS) tapes were welded onto carbon woven fabric reinforced PPS laminates. The

  12. A simple method for determining the lattice parameter and chemical composition in ternary bcc-Fe rich nanocrystals

    International Nuclear Information System (INIS)

    Moya, Javier A.; Gamarra Caramella, Soledad; Marta, Leonardo J.; Berejnoi, Carlos

    2015-01-01

    Highlights: • A method for determining composition in ternary nanocrystals is presented. • X-ray diffraction and Mössbauer spectroscopy data were employed. • We perform theoretical charts for lattice parameter of Fe-rich ternary alloys. • A linear relationship in lattice parameter for binary alloys is evaluated. • A parabolic relationship is proposed for the Fe–Co–Si alloy. - Abstract: Charts containing lattice parameters of Fe 1−x (M,N) x ternary systems with M and N = Si, Al, Ge or Co, and 0 ⩽ x ⩽ ∼0.3, were developed by implementing a linear relationship between the respective binary alloys with the same solute content of the ternary one. Charts were validated with experimental data obtained from literature. For the Fe–Co–Si system, the linear relationship does not fit the experimental data. For the other systems (except the Fe–Co–Ge one where no experimental data was found), the lineal relationship constitute a very good approximation. Using these charts and the lattice parameter data obtained from X-ray diffraction technique combining with the solute content data obtained from Mössbauer spectroscopy technique it is possible to determine the chemical composition of nanograins in soft magnetic nanocomposite materials and some examples are provided

  13. A simple method for determining the lattice parameter and chemical composition in ternary bcc-Fe rich nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Moya, Javier A., E-mail: jmoya.fi.uba@gmail.com [Grupo Interdisciplinario en Materiales-IESIING, Universidad Católica de Salta, INTECIN UBA-CONICET, Salta (Argentina); Gamarra Caramella, Soledad; Marta, Leonardo J. [Grupo Interdisciplinario en Materiales-IESIING, Universidad Católica de Salta, INTECIN UBA-CONICET, Salta (Argentina); Berejnoi, Carlos [Universidad Nacional de Salta, Facultad de Ingeniería, Salta (Argentina)

    2015-05-15

    Highlights: • A method for determining composition in ternary nanocrystals is presented. • X-ray diffraction and Mössbauer spectroscopy data were employed. • We perform theoretical charts for lattice parameter of Fe-rich ternary alloys. • A linear relationship in lattice parameter for binary alloys is evaluated. • A parabolic relationship is proposed for the Fe–Co–Si alloy. - Abstract: Charts containing lattice parameters of Fe{sub 1−x}(M,N){sub x} ternary systems with M and N = Si, Al, Ge or Co, and 0 ⩽ x ⩽ ∼0.3, were developed by implementing a linear relationship between the respective binary alloys with the same solute content of the ternary one. Charts were validated with experimental data obtained from literature. For the Fe–Co–Si system, the linear relationship does not fit the experimental data. For the other systems (except the Fe–Co–Ge one where no experimental data was found), the lineal relationship constitute a very good approximation. Using these charts and the lattice parameter data obtained from X-ray diffraction technique combining with the solute content data obtained from Mössbauer spectroscopy technique it is possible to determine the chemical composition of nanograins in soft magnetic nanocomposite materials and some examples are provided.

  14. Parameters influencing the yield and composition of the essential oil from Cretan Vitex agnus-castus fruits.

    Science.gov (United States)

    Sørensen, J M; Katsiotis, S T

    2000-04-01

    Mature and immature fruits of a Cretan Vitex agnus-castus L. population were chosen to investigate different parameters such as comminution, maturity, distillation period and extraction method influencing the essential oil yield and composition. The effect of the comminution and the maturity of the plant material showed highly significant differences in yield and composition of the essential oils obtained, as well as the distillation duration from one to five hours and the method applied (hydrodistillation and simultaneous distillation extraction). The variation of 36 essential oil components due to the parameters applied was studied. The results showed that many different essential oil qualities can be obtained from the same plant material according to the parameters employed in its extraction. Entire fruits hydrodistilled for one hour yielded an oil much richer in monoterpene hydrocarbons and oxygenated compounds whereas the best combination to obtain an oil rich in less volatile compounds is by SDE of comminuted fruits for five hours. For mature fruits the main components varied as follows due to the parameters studied: sabinene 16.4-44.1%, 1,8-cineole 8.4-15.2%, beta-caryophyllene 2.1-5.0%, and trans-beta-farnesene 5.0-11.7%.

  15. Optimization of Blending Parameters and Fiber Size of Kenaf-Bast-Fiber-Reinforced the Thermoplastic Polyurethane Composites by Taguchi Method

    Directory of Open Access Journals (Sweden)

    Y. A. El-Shekeil

    2013-01-01

    Full Text Available “Kenaf-fibers- (KF-” reinforced “thermoplastic polyurethane (TPU” composites were prepared by the melt-blending method followed by compression molding. Composite specimens were cut from the sheets that were prepared by compression molding. The criteria of optimization were testing the specimens by tensile test and comparing the ultimate tensile strength. The aim of this study is to optimize processing parameters (e.g., processing temperature, time, and speed and fiber size using the Taguchi approach. These four parameters were investigated in three levels each. The L9 orthogonal array was used based on the number of parameters and levels that has been selected. Furthermore, analysis of variance (ANOVA was used to determine the significance of different parameters. The results showed that the optimum values were 180°C, 50 rpm, 13 min, and 125–300 micron for processing temperature, processing speed, processing time, and fiber size, respectively. Using ANOVA, processing temperature showed the highest significance value followed by fiber size. Processing time and speed did not show any significance on the optimization of TPU/KF.

  16. Parameter Sensitivity Analysis on Deformation of Composite Soil-Nailed Wall Using Artificial Neural Networks and Orthogonal Experiment

    Directory of Open Access Journals (Sweden)

    Jianbin Hao

    2014-01-01

    Full Text Available Based on the back-propagation algorithm of artificial neural networks (ANNs, this paper establishes an intelligent model, which is used to predict the maximum lateral displacement of composite soil-nailed wall. Some parameters, such as soil cohesive strength, soil friction angle, prestress of anchor cable, soil-nail spacing, soil-nail diameter, soil-nail length, and other factors, are considered in the model. Combined with the in situ test data of composite soil-nail wall reinforcement engineering, the network is trained and the errors are analyzed. Thus it is demonstrated that the method is applicable and feasible in predicting lateral displacement of excavation retained by composite soil-nailed wall. Extended calculations are conducted by using the well-trained intelligent forecast model. Through application of orthogonal table test theory, 25 sets of tests are designed to analyze the sensitivity of factors affecting the maximum lateral displacement of composite soil-nailing wall. The results show that the sensitivity of factors affecting the maximum lateral displacement of composite soil nailing wall, in a descending order, are prestress of anchor cable, soil friction angle, soil cohesion strength, soil-nail spacing, soil-nail length, and soil-nail diameter. The results can provide important reference for the same reinforcement engineering.

  17. Influence of compositions on thermal stability and thermodynamic parameter in Ca-Mg-Cu bulk metallic glasses

    Science.gov (United States)

    Deshmukh, A. A.; Khond, A. A.; Palikundwar, U. A.

    2018-05-01

    In the present manuscript, influence of compositions on thermal stability (ΔTx) and thermodynamic parameter PHSS of Ca-Mg-Cu bulk metallic glasses (BMGs) is evaluated. The statistical approach of regression analysis is adopted to investigate the compositional variation with ΔTx and PHSS. It is found that calcium (Ca) and copper (Cu) content has goodlinear relationship with ΔTx and PHSS. It is observed that with increase in Ca content, ΔTx and PHSS decreases. On the other hand, increase in Cu content, both ΔTx and PHSS increases. Correlation fit of magnesium (Mg) content with both ΔTx and PHSS is very poor. A graph is also plotted to understand the relationship between ΔTx and PHSS. Result of the relationship between ΔTx and PHSS reveals that the alloy composition having more negative value of PHSS will have more stability. Therefore, compositions with more negative value of PHSS will lead to ease of BMGs formation in Ca-Mg-Cu alloy system and hence more stable it will be. It is expected that these results will be supportive in identifying the compositions having these elements for making BMGs.

  18. Activation method for measuring the reaction rates and studying the neutron spectra parameters, based on using the unified composition detectors

    International Nuclear Information System (INIS)

    Demidov, A.M.; Dikarev, V.S.; Efimov, B.V.; Ionov, V.S.; Marin, S.V.

    2005-01-01

    The method proposed for estimation of parameters thermal and epithermal parts of energy distribution of neutrons is described. The method based on application of activation measuring with use of unified composition detectors (UCD) and samples of fuel. The method is applicable for definition of neutron spectrum parameters and velocities of division in fuel of nuclear installations. Theoretical bases and the description of a method, expedients of manufacturing and calibration for the detectors, the experimental data, carried out in RRC KI are given and processing of experimental data, and also. The parametric model of a spectrum constructed on the basis of Westcott's formalism is described. The parameter of stiffness is entered and its role for temperature of neutron gas, spectral coefficients of isotopes of detectors, the transition area thermal and epithermal parts of neutron spectra is observationally appreciated. It is offered to confirm the found results by calculations with use of MCU Monte Carlo code [ru

  19. STUDY OF SINGLE WALLED CARBON NANOTUBE REINFORCED POLYMER COMPOSITES BY HANSEN SOLUBILITY PARAMETERS

    DEFF Research Database (Denmark)

    Ma, Jing

    reinforcement of the polymer by the addition of SWNTs. Existence of agglomerates, voids, and the lower glass transition temperature of epoxy resin, may give the negative effect on the mechanical properties of nanocomposite materials. In the design aspect of the composite material, HSP could help match SWNTs...

  20. Effect of fed- versus fasted state resistance training during Ramadan on body composition and selected metabolic parameters in bodybuilders.

    Science.gov (United States)

    Trabelsi, Khaled; Stannard, Stephen R; Ghlissi, Zohra; Maughan, Ronald J; Kallel, Choumous; Jamoussi, Kamel; Zeghal, Khaled M; Hakim, Ahmed

    2013-04-25

    Muslim bodybuilders often continue training during Ramadan. However, the effect of resistance training in a fasted versus a fed state during Ramadan on body composition and metabolic parameters in bodybuilders is not well known. The aim of this study was to evaluate the effects of resistance training in a fasted versus a fed state during Ramadan on body composition and metabolic parameters in bodybuilders. Sixteen men were allocated to two groups: Eight practicing resistance training in the late afternoon in a fasted state (FAST), and eight training in the late evening in an acutely fed state (FED) during Ramadan. All visited the laboratory in the morning two days before the start of Ramadan (Bef-R) and on the 29th day of Ramadan (End-R) for anthropometric measurement, completion of a dietary questionnaire, and provision of fasting blood and urine samples. Body mass and body fat percentage remained unchanged in FAST and FED during the whole period of the investigation. Both FAST and FED experienced an increase in the following parameters from Bef-R to End-R: urine specific gravity (1%; p = 0.028, p = 0.004 respectively), serum concentrations of urea (4%, p = 0.006; 7%, p = 0.004 respectively), creatinine (5%, p = 0.015; 6%, p = 0.04 respectively), uric acid (17%; p Ramadan does not affect body mass and body composition of bodybuilders. Additionally, Ramadan fasting induced changes in urinary and some biochemical parameters, but these changes were not different according to when the training occurred.

  1. Effects of glass composition on the residual rate of alteration and modelling parameters

    International Nuclear Information System (INIS)

    Fleury, Benjamin

    2013-01-01

    This PhD thesis deals with the long-term behavior of the French nuclear glasses R7T7. An experiment plan (based on 27 glass compositions) is developed for studying the effect of glass composition on the residual rate of alteration. The impact of Mg-phase precipitation on glass alteration is also studied and several modelling exercises are performed. There is one order of magnitude between the different measurements (rate or pH...) associated with the different glass compositions. The statistical treatment of these measurements results in predictive equations and several observable trends are valid for all materials with a composition complying with the experiment plan conditions. The effect of Si, Na, B and Al on alteration (.i.e, gel and secondary phase's formation, pH) is confirmed, the influence of Zn, Zr and Ni-Co is evidenced. The role of Cr has to be clarified. Experiments show that glass alteration rate in underground water, which contains high level of Ca and Mg, is one order of magnitude higher than in the case of pure water. The glass composition plays the same role for the alteration in the two types of solution. During alteration, the late addition of Mg introduces a time lag in the resumption response because silicon is first provided from partial dissolution of the previously-formed alteration gel. The nucleation process does not limit Mg-silicate precipitation whereas a pH above 8-8.5 is necessary for Mg-silicate precipitation. The glass alteration rate can be a limiting factor if the quantity of Mg supplied to the reaction is enough. The Mg silicate phase seems to have systematically a molar ratio Mg/Si between 0.2 and 0.4. It is also shown that the air tightness of the reactor influences the rate of dissolution of CO 2 in the solution leading to a decrease of pH. Finally, modelling exercises with GRAAL show promising results. Such modelling is required in order to extend the prediction of the long-term alteration behavior to different glass

  2. Fatty acid composition indicates two types of metabolic syndrome independent of clinical and laboratory parameters.

    Science.gov (United States)

    Žák, A; Burda, M; Vecka, M; Zeman, M; Tvrzická, E; Staňková, B

    2014-01-01

    Dietary composition and metabolism of fatty acids (FA) influence insulin resistance, atherogenic dyslipidemia and other components of the metabolic syndrome (MS). It is known that patients with MS exhibit a heterogeneous phenotype; however, the relationships of individual FA to MS components have not yet been consistently studied. We examined the plasma phosphatidylcholine FA composition of 166 individuals (68F/98M) with MS and of 188 (87F/101M) controls. Cluster analysis of FA divided the groups into two clusters. In cluster 1, there were 65.7 % of MS patients and 37.8 % of controls, cluster 2 contained 34.3 % of patients and 62.2 % of controls (Pinsulin resistance).

  3. Modal parameter identification of all-GFRP composite cable-stayed footbridge in Denmark

    Directory of Open Access Journals (Sweden)

    Górski Piotr

    2017-01-01

    Full Text Available The aim of this paper is to investigate of dynamic characteristics of cable-stayed Fiberline Bridge in Kolding, Denmark, made entirely of Glass Fiber Reinforced Polymer (GFRP composite. During examination based on in situ free-decay measurements and using accelerometers under human jumping the primary five natural frequencies, corresponding mode shapes and damping ratios of the footbridge were identified. The Peak Picking (PP and Frequency Domain Decomposition (FDD approaches were applied to identify the natural frequencies and mode shapes. The corresponding damping ratios were extracted by a linear regression on the extremes of modal decays. The estimated damping ratios were compared with published data for selected footbridges made of various conventional materials. The obtained experimental results provide a relevant data regarding the dynamic response prediction or structural health monitoring of all-GFRP composite footbridges.

  4. Cement based composites for thin building elements: Fracture and fatigue parameters

    Czech Academy of Sciences Publication Activity Database

    Seitl, Stanislav; Bílek, V.; Keršner, Z.; Veselý, J.

    2010-01-01

    Roč. 2, č. 1 (2010), s. 911-916 E-ISSN 1877-7058. [Fatigue 2010. Praha, 06.06.2010-11.06.2010] R&D Projects: GA ČR GA103/08/0963 Institutional research plan: CEZ:AV0Z20410507 Keywords : Cement-based composites * Fatigue concrete * Wöhler curve * Fibers Subject RIV: JL - Materials Fatigue, Friction Mechanics

  5. Multi Parameter Flow Meter for On-Line Measurement of Gas Mixture Composition

    Directory of Open Access Journals (Sweden)

    Egbert van der Wouden

    2015-04-01

    Full Text Available In this paper we describe the development of a system and model to analyze the composition of gas mixtures up to four components. The system consists of a Coriolis mass flow sensor, density, pressure and thermal flow sensor. With this system it is possible to measure the viscosity, density, heat capacity and flow rate of the medium. In a next step the composition can be analyzed if the constituents of the mixture are known. This makes the approach universally applicable to all gasses as long as the number of components does not exceed the number of measured properties and as long as the properties are measured with a sufficient accuracy. We present measurements with binary and ternary gas mixtures, on compositions that range over an order of magnitude in value for the physical properties. Two platforms for analyses are presented. The first platform consists of sensors realized with MEMS fabrication technology. This approach allows for a system with a high level of integration. With this system we demonstrate a proof of principle for the analyses of binary mixtures with an accuracy of 10%. In the second platform we utilize more mature steel sensor technology to demonstrate the potential of this approach. We show that with this technique, binary mixtures can be measured within 1% and ternary gas mixtures within 3%.

  6. The effects of intermittent, CD4-guided antiretroviral therapy on body composition and metabolic parameters

    NARCIS (Netherlands)

    Martinez, Esteban; Visnegarwala, Fehmida; Grund, Birgit; Thomas, Avis; Gibert, Cynthia; Shlay, Judith; Drummond, Fraser; Pearce, Daniel; Edwards, Simon; Reiss, Peter; El-Sadr, Wafaa; Carr, Andrew

    2010-01-01

    Objective: To assess the effects of decreased antiretroviral therapy exposure on body fat and metabolic parameters. Design: Substudy of the Strategies for Management of Anti-Retroviral Therapy study, in which participants were randomized to intermittent CD4-guided [Drug Conservation (DC) group] or

  7. Impact of meteorological parameters on extracted landfill gas composition and flow

    DEFF Research Database (Denmark)

    Fathi Aghdam, Ehsan; Scheutz, Charlotte; Kjeldsen, Peter

    2018-01-01

    The objective of this study was to investigate the impact of four pre-selected meteorological parameters (barometric pressure, wind speed, ambient temperature and solar radiation) on recovered landfill gas (LFG) flow, methane (CH4) content of the LFG and the recovered CH4 flow by performing...

  8. Genetic Parameters for carcass composition and pork quality estimated in a commercial production chain

    NARCIS (Netherlands)

    Wijk, van H.J.; Arts, D.J.G.; Matthews, J.O.; Webster, M.; Ducro, B.J.; Knol, E.F.

    2005-01-01

    Breeding goals in pigs are subject to change and are directed much more toward retail carcass yield and meat quality because of the high economic value of these traits. The objective of this study was to estimate genetic parameters of growth, carcass, and meat quality traits. Carcass components

  9. Impact of physicochemical parameters on phytoplankton compositions and abundances in Selameko Manmade Reservoir, Debre Tabor, South Gondar, Ethiopia

    Science.gov (United States)

    Wassie, Tilahun Adugna; Melese, Ayalew Wondie

    2017-07-01

    Impact of physicochemical parameters on 2 compositions and abundances in Selameko Reservoir, Debre Tabor, South Gondar from August 2009 to May 2010 was assessed. Water quality parameters, such as temperature, water transparency, water depth, dissolved oxygen, pH, total dissolved solids, phosphate, nitrate, and silicate were measured in situ from two sites (littoral and open water zone) of the reservoir. Phytoplankton compositions and abundances were analyzed in Tana fisheries and other aquatic organisms' research center. ANOVA result of the physicochemical parameters included chlorophyll-a showed the presence of significance difference among seasons and between sites ( P < 0.05). A total of seven families, 36 genera from three groups (Diatom, Blue green algae and Green algae) of phytoplankton were identified during the study period. From all groups, diatoms were the most abundant at both sites and Blue green algae were the least abundant. ANOVA of all phytoplankton showed highly significant difference among seasons and between sites ( P < 0.05). ANOVA of all phytoplankton showed highly significant difference among seasons and between sites ( P < 0.05). Based on the stepwise regression, a total number of phytoplanktons had positive correlation with some of the physicochemical parameters (R2 = 0.99, P < 0.001, N = 16). The study concluded that some of physicochemical parameters (NO3-N and PO4-P) indicated the presence of reservoir water pollution. This is supported by the presence of pollution-resistant phytoplankton species such as Melosira and Microcystis. The reservoir water was eutrophic (productive) throughout the year. To avoid such pollution, basin and reservoir management are recommended.

  10. Investigation of mechanism and critical parameters for removal of arsenic from water using Zr-TiO2 composite.

    Science.gov (United States)

    Anđelković, I; Amaizah, N R R; Marković, S B; Stanković, D; Marković, M; Kuzmanović, D; Roglić, G

    2017-09-01

    Using the microwave-hydrothermal method for the synthesis of composite, high surface density of hydroxyl groups, as an active adsorption sites for arsenic, was obtained. Adsorption mechanisms of As(III) and As(V) onto zirconium-doped titanium dioxide (Zr-TiO 2 ) were investigated and proposed using macroscopic and microscopic methods. Obtained results are suggesting inner-sphere and outer-sphere adsorption mechanisms for As(III) and As(V), respectively. This allowed us to identify parameters that are critical for the successful removal of arsenic from water, which is essential information for further optimization of the removal process. The composite was further applied for the removal of As(III) and As(V) from water in a dynamic flow through the reactor. Column study proved that the removal of both arsenic species below the value recommended by WHO can be achieved. Elution of As(III) and As(V) from the composite can be done by using small amounts of 0.01 M NaOH solution resulting in preconcentration of arsenic species and possible multiple usage of composite.

  11. The use of an electric field as a processing parameter in the combustion synthesis of ceramics and composites

    International Nuclear Information System (INIS)

    Munir, Z.A.

    1996-01-01

    The imposition of an electric field is shown to activate self-propagating combustion reactions and thus makes possible the synthesis of a variety of ceramic and composite phases. Experimental observations and modeling studies indicated that activation is accomplished by the localized effect of the current. The relationship between wave propagation and the direction of the applied field was investigated. The synthesis of composites by field-activated combustion synthesis (FACS) was demonstrated. It was shown that the imposition of a field during the combustion synthesis of MoSi 2 results in a decrease /in the product particle size. The results suggest that the field can be used as a processing parameter in self-propagating combustion synthesis

  12. A study on the influence of process parameters on the Mechanical Properties of 3D printed ABS composite

    International Nuclear Information System (INIS)

    Christiyan, K.G. Jaya; Chandrasekhar, U.; Venkateswarlu, K.

    2016-01-01

    Additive Manufacturing (AM) technologies have been emerged as a fabrication method to obtain engineering components within a short span of time. Desktop 3D printing, also referred as additive layer manufacturing technology is one of the powerful method of rapid prototyping (RP) technique that fabricates three dimensional engineering components. In this method, 3D digital CAD data is converted directly to a product. In the present investigation, ABS + hydrous magnesium silicate composite was considered as the starting material. Mechanical properties of ABS + hydrous magnesium silicate composite material were evaluated. ASTM D638 and ASTM D760 standards were followed for carrying out tensile and flexural tests, respectively. Samples with different layer thickness and printing speed were prepared. Based on the experimental results, it is suggested that low printing speed, and low layer thickness has resulted maximum tensile and flexural strength, as compared to all the other process parameters samples. (paper)

  13. Assessment of nutrition, supplementation and body composition parameters on the example of professional volleyball players.

    Science.gov (United States)

    Zapolska, Joanna; Witczak, Katarzyna; Mańczuk, Angelika; Ostrowska, Lucyna

    2014-01-01

    Volleyball is a team game belonging to a group of sports disciplines that involve indirect fighting. Adequate energy coverage in athletes is a crucial issue. It depends primarily on the type, intensity and duration of physical activity related to the sports discipline practiced and to the training cycle duration. The average energy requirement in sportsmen is 50% higher than that of adults. The aim of the study was to characterize the mode of nutrition, including dietary supplements and to assess somatic indices in female volleyball players of the AZS Bialystok team. The study involved 17 women. Research tools included a questionnaire consisting of 24-hour recall, a questionnaire survey concerning supplement intake and body composition analysis performed using a bioimpedance analyzer InBody 220. Data analysis indicates that the anthropometric characteristics and body composition of the AZS Bialystok players meet the recommendations associated with the somatic features in volleyball. Daily diet of the volleyball players were of low-energy with regard to the recommendations for physically active people, with very low supply of carbohydrates and dietary fiber, excessive proportion of saturated fatty acids and dietary cholesterol, and too low content of monounsaturated and polyunsaturated fatty acids. Supply of vitamins and minerals was found to be alarmingly low, especially of iron and calcium; diet supplementation was insufficient. No significant abnormalities were noted in body composition of the study athletes. However, they are recommended to increase muscle mass and slightly reduce body fat. Results of diet evaluation show the need for education in the field of nutrition and the necessity of further research into dietary habits among sportsmen.

  14. Parameters affecting the production of Al-Al/sub 2/O/sub 3/ metal matrix particulate composite, (MMPC)

    International Nuclear Information System (INIS)

    Zaid, A.I.O.; Jaber, F.

    2003-01-01

    Aluminum-ceramic composites were made by powder metallurgy up to early 80's. Since then several attempts Metal have been made to produce these composites by liquid metallurgy method. Different techniques have been reported to produce these composites by this method and many difficulties have been encountered in wetting the particles by the molten metal due to the difference in densities which caused non uniform distribution of the particles in the matrix resulting in poor mechanical strength. In this paper, the production of aluminum-aluminum oxide (Al-Al/sub 2/O/sub 3/) metal matrix composite by different techniques is investigated. These include injection, centrifugal vortex, compocasting and a newly suggested method, modified vortex technique. The effect of the process parameters are investigated and discussed and the optimum process conditions were determined. It was found that preheating of the alumina powder for one hour at 1050 deg. before introducing it to the aluminum melt is vital to be accepted by the melt. Incorporation of the alumina particles by injecting them below the surface of the melt resulted in better wettability of the particles but no more than 10% volume fraction was achieved. Similarly, in the centrifuged casting technique, the same volume fraction of the Al/sub 2/O/sub 3/ particles was obtained and in both techniques existence of porosity was observed. The vortex technique, when its parameters were optimized resulted in higher volume fraction, as 25% of alumina particles was achieved with better particle distribution than those obtained by the injection and centrifuged casting methods. Comparison among the different techniques is made based on volume fraction, particle distribution, soundness and micro segregation. A new method, based on modifying the vortex technique is given and discussed. The mechanical strength and hardness of Al-Al/sub 2/O/sub 3/ MMPC produced by this method were determined. It was found that an increase of 100% in

  15. The chemical composition and parameters of production processes influence on structure and properties of W-Ni-Fe alloys

    International Nuclear Information System (INIS)

    Majewski, T.; Przetakiewicz, W.

    2000-01-01

    Tungsten heavy alloys, i.e. tungsten based metal-matrix composites are characterized by unique properties, because except their high hardness, strength and density, they also possess excellent ductility, impact strength, machinability and corrosion resistance. This combination of properties makes these alloys suitable for wide range of engineering applications, e.g. in the mechanical engineering, in the mining, sport and medicine and also in the armament and aviation. Production process of these materials consists of many phases and it is very difficult to accomplish, because properties of heavy alloys are extremely sensitive to processing history. In this article dependence of chemical composition of mixture of powders on structure and mechanical properties of W-Ni-Fe alloys was determined. It was found that increase of tungsten contents and Ni/Fe ratio causes reduction of ductility and increase of growth rate of tungsten particle. There is the maximum ultimate tensile strength of W-Ni-Fe alloys with content of tungsten 93%. The study also presents relationship between these properties and succeeding parameters of production process: composition of sintering atmosphere, time and temperature following heat treatment and plastic working. Using a wet hydrogen atmosphere (with high dew point) causes reduction of porosity and improvement of mechanical properties. With sintering temperature above 1500 o C these parameters decrease. If the sintering time is elongated above 1 h also density and mechanical properties of heavy alloys decrease. Tungsten heavy alloys are also used for production of kinetic energy penetrators and so properties for different range of strain rates were compared. It was found that yield and failure strengths increase with increasing strain rate, failure strain decreases with increasing strain rate. This information can help in optimization the production process of such composites. (author)

  16. Parameter design and analysis in continuous drive friction welding of Al6061/SiCp composites

    Energy Technology Data Exchange (ETDEWEB)

    Adalrasan, R. [Saveetha Engineering College, Chennai (India); Sundaram, A. Shanmuga [Sree Sastha Institute of Engineering and Technology, Chennai (India)

    2015-02-15

    Continuous drive friction welding (FW) had found profound industrial applications as an economical solid state joining process. The welding parameters such as frictional pressure, upset pressure, burn off length and rotational speed were found to influence the quality of joints. In the present study, Al6061/SiC{sub p} rods were joined by friction welding. The welding trials were designed by using Taguchi's L{sub 9} orthogonal array. Tensile strength and micro hardness of the joints were observed as the quality characteristics after each trial. The urge for parameter design had prompted the disclosure of a new integrated methodology based on technique for order of preference by similarity to ideal solution (TOPSIS) and grey relational analysis (GRA). The effectiveness of the proposed approach of T-GRA was validated by conducting a confirmation test and the field emission scanning electron microscope (FESEM) images of the fractured surface were also examined.

  17. Investigating the CO 2 laser cutting parameters of MDF wood composite material

    Science.gov (United States)

    Eltawahni, H. A.; Olabi, A. G.; Benyounis, K. Y.

    2011-04-01

    Laser cutting of medium density fibreboard (MDF) is a complicated process and the selection of the process parameters combinations is essential to get the highest quality cut section. This paper presents a means for selecting the process parameters for laser cutting of MDF based on the design of experiments (DOE) approach. A CO 2 laser was used to cut three thicknesses, 4, 6 and 9 mm, of MDF panels. The process factors investigated are: laser power, cutting speed, air pressure and focal point position. In this work, cutting quality was evaluated by measuring the upper kerf width, the lower kerf width, the ratio between the upper kerf width to the lower kerf width, the cut section roughness and the operating cost. The effect of each factor on the quality measures was determined. The optimal cutting combinations were presented in favours of high quality process output and in favours of low cutting cost.

  18. The Effects of Compliance with Nutritional Counselling on Body Composition Parameters in Head and Neck Cancer Patients under Radiotherapy

    Directory of Open Access Journals (Sweden)

    D. Hopanci Bicakli

    2017-01-01

    Full Text Available Background. Radiotherapy (RT has been associated with increased risk of malnutrition in cancer patients, particularly in those with head and neck cancer (HNC. The aim of this prospective study was to evaluate the effects of compliance of patients with individual dietary counselling on body composition parameters in HNC patients under RT. Material and Methods. Sixty-nine consecutive patients (mean age: 61.0±13.8 were prospectively followed. Bioelectrical impedance analysis (BIA was performed to determine body composition parameters before, in the middle of, and at the end of RT. All patients received nutritional counselling and majority of them (94.6% received oral nutritional supplement (ONS during RT or chemoradiotherapy. If a patient consumed ≥75% of the recommended energy and protein intake via ONS and regular food, he/she was considered to be “compliant” (n=18, while those who failed to meet this criteria were considered to be “noncompliant” (n=30. Results. Body mass index, weight, fat percentage, fat mass, fat free mass, and muscle mass did not decrease significantly over time in compliant patients, but in noncompliant patients, all of these indices decreased significantly from baseline compared to the end of treatment (p<0.001. Hand grip strength did not differ significantly between the two groups at baseline and over time in each group. When retrospectively evaluated, heavy mucositis was less commonly observed in compliant than noncompliant patients (11.1% versus 88.9%, resp. (p<0.009. Conclusion. We conclude that body composition parameters were better in head and neck cancer patients considered as compliant with nutritional counselling than noncompliant ones during RT period.

  19. The evaluation of physico-chemical parameters of the Nasrand Plutonic complex by using mineral composition

    Directory of Open Access Journals (Sweden)

    Fatemeh Sarjoughian

    2017-02-01

    Full Text Available Introduction Mineral composition is sensitive to variations in the composition of the magma and can be used to characterize the physical conditions of crystallization such as temperature, pressure, oxygen fugacity and water content. The studies have demonstrated that geobarometery by amphibole provides a tool for determining the depth of crystallization and knowledge of the depth of crystallization of hornblende through to solidification of calc-alkaline plutons (Anderson and Smith, 1995. The composition of pyroxene can be used as crystallization pressure and temperature indicators of pyroxene too. Anlytical methods The mineral compositions of the Nasrand intrusion were determined by electron microprobe, with special emphasis on the amphibole, feldspar, and pyroxene at the Naruto University, Japan, the EPMA (Jeol- JXA-8800R was used at operating conditions of 15 kV, 20 nA acceleration voltage and 20s counting time. Results The Nasrand intrusion (33°13'–33°15' N, 52°33'–52°34'E with an outcrop area of about 40 km2 is situated in the Urumieh–Dokhtar magmatic belt, SE of Ardestan. It is composed of granite and granodiorite and various dikes of diorite and gabbro which are intruded in it. It is intruded into Eocene volcanic rocks, including andesite, rhyolite, and dacite. The petrographical studies indicate that the granitic and granodioritic rocks contain major minerals such as quartz, K-feldspar, plagioclase, and amphibole, which are in an approximate equilibrium state. The gabbroic-dioritic dikes usually show microgranular porphyric texture. They mainly consist of plagioclase, amphibole, and pyroxene. The plagioclase shows variable composition from albite to oligoclase in the granitoid rocks and from oligoclase to bytownite in dioritic and gabbroic dikes (Deer et al., 1991. The amphiboles are calcic and their composition varies from hornblende to actinolite, whereas the composition of the basic dikes is inclined to hastingsite (Leake et

  20. Wood-polymer composites from Philippine tree plantation species by radiation polymerization I. Uptake and irradiation parameters

    International Nuclear Information System (INIS)

    Dela Rosa, A.M.; Castaneda, S.S.; Real, M.P.N.; Sta Ana, L.P.; Mosteiro, A.P.; Bauza, E.; Carandang, J.P.

    1993-01-01

    Radiation catalyzed polymerization of methyl methacrylate (MMA) in various Philippine tree plantation species were investigated. Wood samples measuring 1x6cm were impregnated with monomer at reduced pressure and gamma irradiated for various doses at a dose rate of 0.53 kGy/h. The parameters used to assess the polymerization reaction were the uptake of monomer by the wood samples, monomer conversion, and polymer loading in the irradiated samples. The uptake and polymerization data indicate that coconut wood, rubber wood, bagras, and Moluccan sau could be potential raw materials for the production of wood-polymer composites (WPC). (author). 6 refs.; 2 figs.; 1 tab

  1. Parameter determination of hereditary models of deformation of composite materials based on identification method

    Science.gov (United States)

    Kayumov, R. A.; Muhamedova, I. Z.; Tazyukov, B. F.; Shakirzjanov, F. R.

    2018-03-01

    In this paper, based on the analysis of some experimental data, a study and selection of hereditary models of deformation of reinforced polymeric composite materials, such as organic plastic, carbon plastic and a matrix of film-fabric composite, was pursued. On the basis of an analysis of a series of experiments it has been established that organo-plastic samples behave like viscoelastic bodies. It is shown that for sufficiently large load levels, the behavior of the material in question should be described by the relations of the nonlinear theory of heredity. An attempt to describe the process of deformation by means of linear relations of the theory of heredity leads to large discrepancies between the experimental and calculated deformation values. The use of the theory of accumulation of micro-damages leads to much better description of the experimental results. With the help of the hierarchical approach, a good approximation of the experimental values was successful only in the first three sections of loading.

  2. Effect of fed- versus fasted state resistance training during Ramadan on body composition and selected metabolic parameters in bodybuilders

    Science.gov (United States)

    2013-01-01

    Background Muslim bodybuilders often continue training during Ramadan. However, the effect of resistance training in a fasted versus a fed state during Ramadan on body composition and metabolic parameters in bodybuilders is not well known. The aim of this study was to evaluate the effects of resistance training in a fasted versus a fed state during Ramadan on body composition and metabolic parameters in bodybuilders. Methods Sixteen men were allocated to two groups: Eight practicing resistance training in the late afternoon in a fasted state (FAST), and eight training in the late evening in an acutely fed state (FED) during Ramadan. All visited the laboratory in the morning two days before the start of Ramadan (Bef-R) and on the 29th day of Ramadan (End-R) for anthropometric measurement, completion of a dietary questionnaire, and provision of fasting blood and urine samples. Results Body mass and body fat percentage remained unchanged in FAST and FED during the whole period of the investigation. Both FAST and FED experienced an increase in the following parameters from Bef-R to End-R: urine specific gravity (1%; p = 0.028, p = 0.004 respectively), serum concentrations of urea (4%, p = 0.006; 7%, p = 0.004 respectively), creatinine (5%, p = 0.015; 6%, p = 0.04 respectively), uric acid (17%; p bodybuilders. Additionally, Ramadan fasting induced changes in urinary and some biochemical parameters, but these changes were not different according to when the training occurred. PMID:23617897

  3. The effect of compositional parameters on the TCLP and PCT durability of environmental glasses

    International Nuclear Information System (INIS)

    Resce, J.L.; Overcamp, T.J.

    1995-01-01

    The relationship between glass composition and the chemical durability of environmental waste glass is very important for both the development of glass formulations and the prediction of glass durability for process control. The development of such a model is extremely difficult for several reasons. Firstly, chemical durability is dependent upon the type of leach test employed; the leach tests themselves being only crude approximations of actual environmental conditions or long term behavior. Secondly, devitrification or crystallinity can also play a major role in durability, but is much more difficult to quantify. Lastly, the development of any one model for all glass types is impractical because of the wide variety of wastestreams, the heterogeneity of the wastestreams, and the large variety of components within each wastestream. Several ongoing efforts have been directed toward this goal, but as yet, no model has been proven acceptable

  4. Experimental investigations on steel-concrete composite columns for varying parameters

    Science.gov (United States)

    Aparna, V.; Vivek, D.; Neelima, Kancharla; Karthikeyan, B.

    2017-07-01

    In this study, the experimental investigations on steel tubes filled with different types of concrete are presented. Steel tubes filled with fibre reinforced concrete using lathe waste and steel tube with concerned confined with steel mesh were investigated. The combinations were compared with steel tubes with conventional concrete. A total of 4 concrete filled steel tube (CFST) combinations were made with tubes of diameter 100 mm with wall thickness 1.6 mm and a height of 300 mm. Axial compression test to examine the resisting capacity of the columns and push-out test for noting the bond strength were performed. Coupon tests were also conducted to determine the mechanical properties of steel. The structural behaviour of the composite columns was evaluated from on the test results. It was observed that steel tube filled fibre reinforced possessed better bond strength and resistance to axial load.

  5. Usage properties of special steels for presurrized water reactors: influence of composition and of manufacturing parameters

    International Nuclear Information System (INIS)

    Seraphin, L.; Mathern, G.; Crolet, J.-L.; Tricot, R.

    1977-01-01

    The development of pressurized water reactor power stations has led to the choice of suitable materials either for the vessels or for the heat exchangers and auxiliary equipment (pumps for example). The most important problems to be solved, considering the low temperatures involved, concern embrittlement with time, and the different forms of corrosion. The quality of the tubes and plates is of primary importance, in particular as regards the absence of defects, the chemical integrity of the surface and the working properties such as weldability. The efforts of manufacturers to meet these different requirements are examined as regards analysis as well as manufacturing parameters and testing procedures [fr

  6. Investigating the CO2 laser cutting parameters of MDF wood composite material

    OpenAIRE

    Eltawahni, Hayat; Olabi, Abdul-Ghani; Benyounis, Khaled

    2011-01-01

    Laser cutting of medium density fibreboard (MDF) is a complicated process and the selection of the process parameters combinations is essential to get the highest quality of the cut section. This paper presents laser cutting of MDF based on design of experiments (DOE). CO2 laser was used to cut three thicknesses 4, 6 and 9 mm of MDF panels. The process factors investigated are: laser power, cutting speed, air pressure and focal point position. In this work, cutting quality was evaluated by me...

  7. Experimental research on the influence of system parameters on the composition shift for zeotropic mixture (isobutane/pentane) in a system occurring phase change

    International Nuclear Information System (INIS)

    Bao, Junjiang; Zhao, Li

    2016-01-01

    Highlights: • The influence of system parameters on the composition shift for zeotropic mixture is studied. • Zeotropic mixture isobutane/pentane is selected as the working fluids. • Circulating composition and charge have the inverse proportion relationship. • The relationship between circulating composition and charge composition is linear. - Abstract: Zeotropic mixture can improve the performance of the thermodynamic cycle ascribed to the better temperature match during the heat transfer process with the characteristics of temperature glide during evaporation and condensing processes. Another characteristic of zeotropic mixture is composition shift. Composition shift means that the circulating composition and charge composition is different and is mainly caused by the two-phase hold-up and different solubility in lubricating oil. The existence of composition shift will affect the design and operation of thermodynamic system. The previous study gave little information about the influence of system parameters on the composition shift in a system occurring phase change. This paper mainly discuss the influence of system parameters on the composition shift for zeotropic mixture in a system occurring phase change as well as the validation of the linear relationship between the circulating composition and the charge composition and the inverse proportion relationship between the circulating composition and the charge mass found based on our previous theory study (Zhao and Bao, 2014). With isobutane and pentane as the research object, the impact of the key system parameters (hot water temperature, mass flow rate of hot water, feed pump frequency, cold water temperature and evaporator length) on composition shift are experimentally carried out. The results show that when the hot water temperature, mass flow rate of hot water and evaporator length increase and cold water temperature decreases, circulating composition will increase. For feed pump frequency, when

  8. Evaluation of Stability Parameters in In-Vessel Compositing of Municipal Solid Waste

    Directory of Open Access Journals (Sweden)

    M. M. Amin

    2011-10-01

    Full Text Available Composting is a reliable technology for production of stabilized organic matter that is suitable for agriculture, but this process should be carefully monitored with appropriate indices. Quality of compost is important from maturity and stability viewpoint, but in most compost factories proper attention is not paid to it. This study was designed to evaluate the stability indices in municipal solid waste composting, for selecting the best index in quality monitoring of the wastes. Processed and shredded municipal solid waste from Isfahan compost plant was used as raw material in an in-vessel composting process. A cylindrical reactor with 1 m height and 50 cm diameter made of Pyrex glass was designed. Air was supplied at a specifically flow rate 0.2 L/min.kg to maintain aerobic condition. NH4+/ NO3 ratio, dehydrogenase enzyme activity (DA, pH, oxidation reduction potential (ORP or Eh and specific oxygen uptake rate (SOUR were used as stability indices. These parameters were measured during 40 days of composting process. Changes in these parameters during this period were surveyed and analyzed. Statistical analysis was carried out to choose best of them. Results showed that among the indices, SOUR can show the different stages of microbial decomposition and a numerical value for compost stability also SOUR value less than 2 mg O2/gVS.h can show the full stability of compost.

  9. [Nutritional status assessment in a group of university students by means of dietary parameters and body composition].

    Science.gov (United States)

    Martínez Roldán, C; Veiga Herreros, P; López de Andrés, A; Cobo Sanz, J Ma; Carbajal Azcona, A

    2005-01-01

    To assess the nutritional status in a young adults by means of dietary parameters and body composition. The sample comprises 49 young men (35 women and 14 men) with a mean age of 21.9 +/- 2.9 ages, at Alfonso X el Sabio University of Madrid. Body composition was analyzed through anthropometrical parameters. By means of validated questionnaires, physical activity performed within a week was assessed, as well as energy and nutrients intake. The later was estimated through a registry of all foods and beverages consumed for the last 14 days performed by each one of the participants (previously instructed) and estimating the amounts by weight or home or standard servings. The resting energy waste was determined by indirect calorimetry and through the Harris-Benedict predictive formula. Body mass index was similar in both men and women (p = 0.10) (23.5 +/- 1.9 and 22.0 +/- 2.8 kg/m2). The percentage of fat obtained through anthropometrics was 16.4 +/- 3.5% and 27.1 +/- 3.8% (p vitamin A in men, with levels below the recommended ones. In some aspects, the diet from this group deviates from current dietary standards. It would be advisable to increase the physical activity that would allow a higher food intake in order to cover for the insufficient intake of some nutrients without energetically unbalancing the diet. The assessment of resting energetic waste by indirect calorimetry seems to better predict the energetic needs.

  10. Evaluation of Dietary Intakes, Body Composition, and Cardiometabolic Parameters in Adolescent Team Sports Elite Athletes: A Cross-sectional Study

    Science.gov (United States)

    Hosseinzadeh, Javad; Maghsoudi, Zahra; Abbasi, Behnood; Daneshvar, Pooya; Hojjati, Atefeh; Ghiasvand, Reza

    2017-01-01

    Background: Nutritional intake is an important issue in adolescent athletes. Proper athletes’ performance is a multifactorial outcome of good training, body composition, and nutritional status. The aim of the present study was to assess nutritional status, body composition, and cardiometabolic factors in adolescent elite athlete's province of Isfahan, Iran. Materials and Methods: In this cross-sectional study, 100 adolescent elite athletes from volleyball, basketball, and soccer teams were selected for the study. Demographic, anthropometric, and cardiometabolic parameters were assessed. Nutritional intakes of participants were recorded using three 24-h recall questioners. Results: Thirty-four female athletes and 66 male athletes participated in this study. Body mass index had not significantly different between the sexes. Energy, protein, carbohydrate, iron, and fat intakes were significantly higher in male athletes (P = 0.02), but calcium and folic acid intakes were not significantly different between the sexes, and Vitamin D intake was significantly higher in females (P = 0.01). Systolic and diastolic blood pressure was significantly higher in males (P = 0.04) and heart rate had not significantly different between the sexes (P = 0.09). Heart murmurs and heart sounds in the majority of participants were normal. Conclusion: All the evaluated anthropometric and cardiometabolic parameters were in normal range in the majority of participants. The results showed that dietary intake in these athletes is approximately normal but micronutrients intake status in these athletes needs to be investigated further and longer. PMID:28904935

  11. Identifying design parameters controlling damage behaviors of continuous fiber-reinforced thermoplastic composites using micromechanics as a virtual testing tool

    KAUST Repository

    Pulungan, Ditho Ardiansyah; Lubineau, Gilles; Yudhanto, Arief; Yaldiz, Recep; Schijve, Warden

    2017-01-01

    In this paper, we propose a micromechanical approach to predict damage mechanisms and their interactions in glass fibers/polypropylene thermoplastic composites. First, a representative volume element (RVE) of such materials was rigorously determined using a geometrical two-point probability function and the eigenvalue stabilization of homogenized elastic tensor obtained by Hill-Mandel kinematic homogenization. Next, the 3D finite element models of the RVE were developed accordingly. The fibers were modeled with an isotropic linear elastic material. The matrix was modeled with an isotropic linear elastic, rate-independent hyperbolic Drucker-Prager plasticity coupled with a ductile damage model that is able to show pressure dependency of the yield and damage behavior often found in a thermoplastic material. In addition, cohesive elements were inserted into the fiber-matrix interfaces to simulate debonding. The RVE faces are imposed with periodical boundary conditions to minimize the edge effect. The RVE was then subjected to transverse tensile loading in accordance with experimental tensile tests on [90]8 laminates. The model prediction was found to be in very good agreement with the experimental results in terms of the global stress-strain curves, including the linear and nonlinear portion of the response and also the failure point, making it a useful virtual testing tool for composite material design. Furthermore, the effect of tailoring the main parameters of thermoplastic composites is investigated to provide guidelines for future improvements of these materials.

  12. Identifying design parameters controlling damage behaviors of continuous fiber-reinforced thermoplastic composites using micromechanics as a virtual testing tool

    KAUST Repository

    Pulungan, Ditho Ardiansyah

    2017-03-31

    In this paper, we propose a micromechanical approach to predict damage mechanisms and their interactions in glass fibers/polypropylene thermoplastic composites. First, a representative volume element (RVE) of such materials was rigorously determined using a geometrical two-point probability function and the eigenvalue stabilization of homogenized elastic tensor obtained by Hill-Mandel kinematic homogenization. Next, the 3D finite element models of the RVE were developed accordingly. The fibers were modeled with an isotropic linear elastic material. The matrix was modeled with an isotropic linear elastic, rate-independent hyperbolic Drucker-Prager plasticity coupled with a ductile damage model that is able to show pressure dependency of the yield and damage behavior often found in a thermoplastic material. In addition, cohesive elements were inserted into the fiber-matrix interfaces to simulate debonding. The RVE faces are imposed with periodical boundary conditions to minimize the edge effect. The RVE was then subjected to transverse tensile loading in accordance with experimental tensile tests on [90]8 laminates. The model prediction was found to be in very good agreement with the experimental results in terms of the global stress-strain curves, including the linear and nonlinear portion of the response and also the failure point, making it a useful virtual testing tool for composite material design. Furthermore, the effect of tailoring the main parameters of thermoplastic composites is investigated to provide guidelines for future improvements of these materials.

  13. Effects of extruded corn on milk yield and composition and blood parameters in lactating dairy cows

    Directory of Open Access Journals (Sweden)

    Igino Andrighetto

    2010-01-01

    Full Text Available According to a 2x2 cross over design, fourteen Holstein dairy cows at 99±55 DIM were fed two diets containing 21.5% DM of either ground corn (GC or extruded corn (EC. Performance and metabolic profile were detected during the third week of each experimental period. DMI and milk yield were not affected by dietary treatments. Milk fat and protein percentage of EC diet were significantly (P<0.10 lower than those of GC diet. Probably the higher rumen degradability of starch from EC thesis modified the synthesis of specific fatty acids leading to a milk fat depression event. Diets did not influence blood parameters, except for lower values of total protein and glucose content in EC diet-fed cows. Results suggested that the dietary inclusion of extruded corn should not be used at the tested level of substitution.

  14. Experimental Investigation of Process Parameters in Drilling LM25 Composites Coated with Multi Wall Carbon Nano Tubes Using Sonication Process

    Directory of Open Access Journals (Sweden)

    Sangeetha M.

    2017-09-01

    Full Text Available Aluminium based metal matrix composites are widely used in automobile components such as cardan shaft of Chevrolet corvette, disc brake and engine push rod. In this experiment a Hybrid Metal Matrix Composites (HMMC are fabricated and drilled. Drilling is the process of making slots in disc brake and thread in the engine parts. The surface quality of the drilled specimen depends on the speed, feed, drill type and the thrust force. Thrust force plays the major role in drilling the specimen. In this experiment HMMCs are fabricated using two processes-called, sonication and casting. Sonication is the process of coating the carbon nanotubes over the silicon carbide particles (SiCp. Semisolid stir casting is used to reinforce the coated SiCp in the LM 25 alloy. A drilling process is performed on HMMC to analyse the extent to which the input parameters influence the thrust force and Ovality. The tools used for drilling are solid carbide tools of three different diameters. Taguchi’s experimental design is adopted for the drilling operation. A mathematical model is used to determine the influence of input parameters on the outputs thrust force and ovality. This paper proves the combination of N3, f1 and d1 of the carbide tool results in the lowest value of thrust force and ovality while drilling HMMCs. In this work the HMMC is prepared by coating the abrasive nature, silicon carbide particle and there is a good interfacial bonding between the reinforced particle and matrix and the drilling process becomes smoother. The new being of this article is the treated ceramics, SiCp with carbon nanotubes. This HMMC shows the improved mechanical properties compared to other metal matrix composites surveyed in the literatures.

  15. 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.

  16. Protein production from whey using Penicillium cyclopium; growth parameters and cellular composition

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J H; Lebeault, J M

    1981-01-01

    The growth parameters of Penicillium cyclopium were evaluated in a continuous culture system for the production of fungal protein from whey. Dilution rates were 0.05-0.20/h under constant conditions of temperature (28 degrees) and pH (3.5). The saturation coefficients in the Monod equation were 0.74 g/l for lactose and 0.14 mg/l for O/sub 2/. For a wide range of dilution rates, the yield was 0.68 g biomass/g lactose and the maintenance coefficient 0.005 g lactose/g biomass-h. The maximum biomass productivity achieved was 2 g biomass/l-h at dilution rates of 0.16-0.17/h with a lactose concentration of 20 g/l in the feed. The crude protein and total nucleic acid contents increased with a dilution rate, crude protein content was 43-54%, and total nucleic acids were 6-9% at dilution rates of 0.05-0.2/h, while the Lowry protein content was almost constant at 37.5% of dry matter.

  17. Evaluation of 2,4-D removal via activated carbon from pomegranate husk/polymer composite hydrogel: Optimization of process parameters through face centered composite design

    International Nuclear Information System (INIS)

    Taktak, Fulya; Ilbay, Zeynep; Sahin, Selin

    2015-01-01

    A new type of polymer composite hydrogel was prepared by introducing activated carbons from pomegranate husk into poly ((2-dimethylamino) ethyl methacrylate) network. The removal of 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous solution was studied with respect to pH of the media, initial 2,4-D concentration and activated carbon content into the polymeric network. Face centered composite design (FCCD) through response surface methodology (RSM) was used for designing the experiments as well as for studying the effects of the process parameters. A quadratic model and a two factor interaction design model were developed for the removal of 2,4-D and adsorption capacity, respectively. The optimum pH of the pesticide solution, activated carbon content into the polymeric network and initial concentration of 2,4-D were found as 3, 2.5 wt% and 100mg/L. 63.245% and 68.805 (mg/g) for the removal of 2,4-D and adsorption capacity were obtained by using Simplex optimization method. Furthermore, the surface characteristics of the adsorbent prepared under optimized conditions were examined by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR).

  18. Evaluation of 2,4-D removal via activated carbon from pomegranate husk/polymer composite hydrogel: Optimization of process parameters through face centered composite design

    Energy Technology Data Exchange (ETDEWEB)

    Taktak, Fulya; Ilbay, Zeynep [Usak Univ, Usak (Turkmenistan); Sahin, Selin [Istanbul University, Istanbul (Turkmenistan)

    2015-09-15

    A new type of polymer composite hydrogel was prepared by introducing activated carbons from pomegranate husk into poly ((2-dimethylamino) ethyl methacrylate) network. The removal of 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous solution was studied with respect to pH of the media, initial 2,4-D concentration and activated carbon content into the polymeric network. Face centered composite design (FCCD) through response surface methodology (RSM) was used for designing the experiments as well as for studying the effects of the process parameters. A quadratic model and a two factor interaction design model were developed for the removal of 2,4-D and adsorption capacity, respectively. The optimum pH of the pesticide solution, activated carbon content into the polymeric network and initial concentration of 2,4-D were found as 3, 2.5 wt% and 100mg/L. 63.245% and 68.805 (mg/g) for the removal of 2,4-D and adsorption capacity were obtained by using Simplex optimization method. Furthermore, the surface characteristics of the adsorbent prepared under optimized conditions were examined by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR).

  19. Identification of a set of macroscopic elastic parameters in a 3D woven composite: Uncertainty analysis and regularization

    KAUST Repository

    Gras, Renaud

    2015-03-01

    Performing a single but complex mechanical test on small structures rather than on coupons to probe multiple strain states/histories for identification purposes is nowadays possible thanks to full-field measurements. The aim is to identify many parameters thanks to the heterogeneity of mechanical fields. Such an approach is followed herein, focusing on a blade root made of 3D woven composite. The performed test, which is analyzed using global Digital Image Correlation (DIC), provides heterogeneous kinematic fields due to the particular shape of the sample. This displacement field is further processed to identify the four in-plane material parameters of the macroscopic equivalent orthotropic behavior. The key point, which may limit the ability to draw reliable conclusions, is the presence of acquisition noise in the original images that has to be tracked along the DIC/identification processing to provide uncertainties on the identified parameters. A further regularization based on a priori knowledge is finally introduced to compensate for possible lack of experimental information needed for completing the identification.

  20. Effects of Processing Parameters on the Forming Quality of C-Shaped Thermosetting Composite Laminates in Hot Diaphragm Forming Process

    Science.gov (United States)

    Bian, X. X.; Gu, Y. Z.; Sun, J.; Li, M.; Liu, W. P.; Zhang, Z. G.

    2013-10-01

    In this study, the effects of processing temperature and vacuum applying rate on the forming quality of C-shaped carbon fiber reinforced epoxy resin matrix composite laminates during hot diaphragm forming process were investigated. C-shaped prepreg preforms were produced using a home-made hot diaphragm forming equipment. The thickness variations of the preforms and the manufacturing defects after diaphragm forming process, including fiber wrinkling and voids, were evaluated to understand the forming mechanism. Furthermore, both interlaminar slipping friction and compaction behavior of the prepreg stacks were experimentally analyzed for showing the importance of the processing parameters. In addition, autoclave processing was used to cure the C-shaped preforms to investigate the changes of the defects before and after cure process. The results show that the C-shaped prepreg preforms with good forming quality can be achieved through increasing processing temperature and reducing vacuum applying rate, which obviously promote prepreg interlaminar slipping process. The process temperature and forming rate in hot diaphragm forming process strongly influence prepreg interply frictional force, and the maximum interlaminar frictional force can be taken as a key parameter for processing parameter optimization. Autoclave process is effective in eliminating voids in the preforms and can alleviate fiber wrinkles to a certain extent.

  1. Body composition, hydration, and related parameters in hemodialysis versus peritoneal dialysis patients.

    Science.gov (United States)

    Devolder, Isabel; Verleysen, Annick; Vijt, Denise; Vanholder, Raymond; Van Biesen, Wim

    2010-01-01

    Maintaining euvolemia is an important goal in patients on renal replacement therapy. However, adequate assessment of volume status in clinical practice is hampered by a lack of accurate measuring tools. A new multifrequency bioimpedance tool has recently been validated. This study compares volume status in peritoneal dialysis (PD) and hemodialysis (HD) patients in a single center. Body Composition Monitoring (BCM; Fresenius Medical Care, Bad Homburg, Germany) was performed in all patients on PD or HD without contraindication. PD patients were measured with a full abdomen; HD patients were measured at the midweek session, once immediately before and once 20 minutes after dialysis. Clinical overhydration was defined as an overhydration-to-extracellular water ratio of >0.15. Total body water, extracellular water, and intracellular water were 33.7 +/- 6.9 L versus 31.8 +/- 8.1 L vs 33.9 +/- 6.7 L, 16.4 +/- 3.9 L vs 15.3 +/- 4.9 L vs 16.8 +/- 3.3 L, and 17.1 +/- 6.2 L vs 16.5 +/- 4.6 L vs 17.2 +/- 3.9 L in the pre-HD, post-HD, and PD patients, respectively (p = NS). In the pre-HD and the PD patients, overhydration was 1.9 +/- 1.7 L and 2.1 +/- 2.3 L, whereas post-HD this was only 0.6 +/- 1.7 L (p < 0.001). Clinical overhydration was more prevalent in pre-HD and PD patients compared to post-HD patients (24.1% vs 22.3% vs 10%, p < 0.001). In multivariate models, overhydration was related to age, male gender, and post-HD status. Although much clinical attention is paid to volume status, 24% of patients still have clinically relevant volume overload. Implementation of a reliable and clinically applicable tool to assess volume status is therefore necessary. It is possible to obtain comparable volume status in PD and HD patients.

  2. Bonding of composite resins to PEEK: the influence of adhesive systems and air-abrasion parameters.

    Science.gov (United States)

    Stawarczyk, Bogna; Taufall, Simon; Roos, Malgorzata; Schmidlin, Patrick R; Lümkemann, Nina

    2018-03-01

    The objective of the study was to investigate the tensile bond strength (TBS) to polyaryletheretherketone (PEEK) after different pretreatment and conditioning methods. Four hundred PEEK specimens were fabricated and allocated to the following air-abrasion methods (n 1  = 80/pretreatment): (i) 50 μm Al 2 O 3 (0.05 MPa); (ii) 50 μm Al 2 O 3 (0.35 MPa); (iii) 110 μm Al 2 O 3 (0.05 MPa); (iv) 110 μm Al 2 O 3 (0.35 MPa); and (v) Rocatec 110 μm (0.28 MPa). These pretreatments were combined with the following conditioning methods (n 2  = 20/pretreatment/conditioning): (a) visio.link (VL); (b) Monobond Plus/Heliobond (MH); (c) Scotchbond Universal (SU); and (d) dialog bonding fluid (DB). After veneering of all specimens with dialog occlusal and aging (28 days H 2 O, 37 °C + 20,000 thermal cycles, 5/55 °C), TBS was measured. Data was analysed using Kaplan-Meier survival analysis with Breslow-Gehan test and Cox-regressions. The major impact on TBS showed the conditioning, followed by the air-abrasion-pressure, while the grain size of the air-abrasion powder did not show any effect. Specimens air-abraded at 0.35 MPa showed the highest survival rates. However, within VL groups, this observation was not statistically significant. Within MH groups, pretreatment using 110 μm Al 2 O 3 and 0.05 MPa resulted in higher survival rates compared to groups treated with 50 and 110 μm Al 2 O 3 using a pressure of 0.35 MPa. The use of VL showed the highest survival rates between the adhesive systems and the TBS values higher than 25 MPa independent of the pretreatment method. As an exception, only VL showed significantly higher survival rates when compared to MH. The adequate choice of the adhesive system and higher pressures improved the TBS between PEEK and veneering resin composite. The particle size had no major impact. According to this study, best veneering of PEEK with dialog occlusal can be achieved by conditioning with visio.link in combination with

  3. The chemical composition of red giants in 47 Tucanae. I. Fundamental parameters and chemical abundance patterns

    Science.gov (United States)

    Thygesen, A. O.; Sbordone, L.; Andrievsky, S.; Korotin, S.; Yong, D.; Zaggia, S.; Ludwig, H.-G.; Collet, R.; Asplund, M.; Ventura, P.; D'Antona, F.; Meléndez, J.; D'Ercole, A.

    2014-12-01

    Context. The study of chemical abundance patterns in globular clusters is key importance to constraining the different candidates for intracluster pollution of light elements. Aims: We aim at deriving accurate abundances for a wide range of elements in the globular cluster 47 Tucanae (NGC 104) to add new constraints to the pollution scenarios for this particular cluster, expanding the range of previously derived element abundances. Methods: Using tailored 1D local thermodynamic equilibrium (LTE) atmospheric models, together with a combination of equivalent width measurements, LTE, and NLTE synthesis, we derive stellar parameters and element abundances from high-resolution, high signal-to-noise spectra of 13 red giant stars near the tip of the RGB. Results: We derive abundances of a total 27 elements (O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Mo, Ru, Ba, La, Ce, Pr, Nd, Eu, Dy). Departures from LTE were taken into account for Na, Al, and Ba. We find a mean [Fe/H] = -0.78 ± 0.07 and [ α/ Fe ] = 0.34 ± 0.03 in good agreement with previous studies. The remaining elements show good agreement with the literature, but including NLTE for Al has a significant impact on the behavior of this key element. Conclusions: We confirm the presence of an Na-O anti-correlation in 47 Tucanae found by several other works. Our NLTE analysis of Al shifts the [Al/Fe] to lower values, indicating that this may be overestimated in earlier works. No evidence of an intrinsic variation is found in any of the remaining elements. Based on observations made with the ESO Very Large Telescope at Paranal Observatory, Chile (Programmes 084.B-0810 and 086.B-0237).Full Tables 2, 5, and 9 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/572/A108Appendix A is available in electronic form at http://www.aanda.org

  4. An FEM-based AI approach to model parameter identification for low vibration modes of wind turbine composite rotor blades

    Science.gov (United States)

    Navadeh, N.; Goroshko, I. O.; Zhuk, Y. A.; Fallah, A. S.

    2017-11-01

    An approach to construction of a beam-type simplified model of a horizontal axis wind turbine composite blade based on the finite element method is proposed. The model allows effective and accurate description of low vibration bending modes taking into account the effects of coupling between flapwise and lead-lag modes of vibration transpiring due to the non-uniform distribution of twist angle in the blade geometry along its length. The identification of model parameters is carried out on the basis of modal data obtained by more detailed finite element simulations and subsequent adoption of the 'DIRECT' optimisation algorithm. Stable identification results were obtained using absolute deviations in frequencies and in modal displacements in the objective function and additional a priori information (boundedness and monotony) on the solution properties.

  5. Chemical composition and fermentative parameters of heart of palm waste produced from Alexander Palm ensiled with chemical additives

    Directory of Open Access Journals (Sweden)

    Geraldo Fábio Viana Bayão

    Full Text Available ABSTRACT The objective of this study was to evaluate the chemical composition and the fermentative parameters of heart of palm waste produced from Alexander Palm, ensiled with chemical additives. Treatments consisted of silage of the sheath with or without calcium oxide. In the silage without calcium oxide, we evaluated the control silage (without additive and the silage enriched with 5.0 g kg−1 urea (urea. In the silage with calcium oxide, we evaluated the silage enriched with 5.0 g kg−1 calcium oxide (control and the silage enriched with 5.0 g kg−1 urea and 5.0 g kg−1 calcium oxide (urea. Experimental silos were distributed in a completely randomized design in a 2 × 2 factorial arrangement (inclusion or lack of lime × inclusion or lack of urea, with four replicates. Crude protein concentration was greater in the silages that received urea, whereas in the case of neutral detergent fiber and acid detergent fiber, the lowest levels were found in the control silage. Control silage had the lowest pH (3.75 and the silages that received lime displayed the lowest lactic acid content. Effluent losses were greater in the control silage and in the silage with lime (56.1 kg t−1 and 58.4 kg t−1, respectively. Silages prepared with waste from heart of palm production and enriched only with urea showed a better chemical composition and improved fermentation parameter estimates. We recommend the use of this waste only with additives that can improve the chemical characteristics of the forage. Without additives, unwanted fermentation processes may occur and compromise the quality of the silage.

  6. Effect of different parameters on machining of SiC/SiC composites via pico-second laser

    Energy Technology Data Exchange (ETDEWEB)

    Li, Weinan; Zhang, Ruoheng [State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an, Shaanxi 10068 (China); Liu, Yongsheng, E-mail: yongshengliu@nwpu.edu.cn [Science and technology on Thermostructure Composite Materials Laboratory, Northwestern Polytechnical University, Xi’an, Shaanxi 710072 (China); Wang, Chunhui; Wang, Jing [Science and technology on Thermostructure Composite Materials Laboratory, Northwestern Polytechnical University, Xi’an, Shaanxi 710072 (China); Yang, Xiaojun [State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an, Shaanxi 10068 (China); Cheng, Laifei [Science and technology on Thermostructure Composite Materials Laboratory, Northwestern Polytechnical University, Xi’an, Shaanxi 710072 (China)

    2016-02-28

    Graphical abstract: - Highlights: • The highlights of the manuscript include the following two aspects. • First, we found that the different machining modes (helical line scanning and single ring line scanning) and processing power of machining have remarkable effect on the surface morphology of the machined area, such as the shape, depth and the formation of different surface structures. • Secondly, we investigated that the debris consisted of C, Si and O was observed on the machined surface. • Some of the Si–C bonds of the SiC matrix and fibers would be transformed into Si–O bonds after machined, depending on the processing power. - Abstract: Pico-second laser plays an important role in modern machining technology, especially in machining high hardness materials. In this article, pico-second laser was utilized for irradiation on SiC/SiC composites, and effects of different processing parameters including the machining modes and laser power were discussed in detail. The results indicated that the machining modes and laser power had great effect on machining of SiC/SiC composites. Different types of surface morphology and structure were observed under helical line scanning and single ring line scanning, and the analysis of their formulation was discussed in detail. It was believed that the machining modes would be responsible to the different shapes of machining results at the same parameters. The processing power shall also influence the surface morphology and quality of machining results. In micro-hole drilling process, large amount of debris and fragments were observed within the micro-holes, and XPS analysis showed that there existed Si–O bonds and Si–C bonds, indicating that the oxidation during processing was incomplete. Other surface morphology, such as pores and pits were discussed as well.

  7. The effects of an exercise training program on body composition and aerobic capacity parameters in Tunisian obese children

    Directory of Open Access Journals (Sweden)

    Sofien Regaieg

    2013-01-01

    Full Text Available Background: The prevalence of children obesity is rising alarmingly in both developed and developing countries. Developing effective exercise programs is a strategy for decreasing this prevalence and limiting obesity-associated long-term comorbidities. Objectives: To determine whether a 16-week training program; in addition to the school physical education and without dietary intervention; could have beneficial effects on body composition and aerobic capacity of obese children. Materials and Methods: Twenty-eight obese children (16 boys, 12 girls; aged 12-14 years were enrolled and were divided into either the exercise group (EG, n = 14 or the control group (CG, n = 14. EG participated in a 16-week aerobic exercises (four 60-min sessions per week at 70-85% of HRmax (maximum heart rate, in addition to the school physical education. Fat-Free Mass (FFM and Fat Mass (FM were assessed with bioelectrical impedance equipment. To assess aerobic capacity, maximal metabolic equivalent of task (METmax and maximal workload (Wmax were estimated with an electronically braked cycle ergometer (type Ergoline 500® . Results: At baseline, there were no differences between the two groups. After the training program, only the EG showed significant reduction in BMI (body mass index and waist circumference compared with the baseline values (P < 0.001. Exercise training significantly decreased FM only in the EG. A significant increase in FFM was seen in both groups; more marked in the EG. There was a significant increase in METmax (P < 0.05 and Wmax (P = 0.02 in the EG, and no significant changes in these parameters were seen in the CG. HRmax significantly decreased only in the EG (P < 0.05. Conclusion: This training program has beneficial effects on body composition and aerobic capacity parameters in obese children. Our intervention has the advantage of providing a sustainable and reproducible school and community approach for the management of children obesity.

  8. The influence of growth parameters on the structure and composition of CuGaS2 epilayers grown by MOVPE

    International Nuclear Information System (INIS)

    Branch, M.S.; Berndt, P.R.; Leitch, A.W.R.; Botha, J.R.; Weber, J.

    2006-01-01

    The influence of various growth parameters on the composition and structure of MOVPE-grown CuGaS 2 is presented. The Cu content of the grown layers is shown to decrease in the direction of the carrier gas flow, whilst the Ga and S content are shown to increase. Changing the flow of Cu(hfac) 2 .Et 3 N to vary the I/III ratio in the vapour phase has a greater effect on the composition of grown epilayers than changing the flow of TEGa. This is indicative of Cu being the minority species present at the growth interface. A larger rate of decrease in the Cu content with an increase in both TEGa and DtBS flows suggests pre-reactions between Cu(hfac) 2 .Et 3 N and both TEGa and DtBS precursors. Lower substrate temperatures are suggested to be thermodynamically unfavourable for the growth of CuGaS 2 , yet enhance the formation of Ga x S y phases. The surface morphology of Cu-rich layers are typically inferior with a high density of crystallites, whilst Cu-poor epilayers are characteristically smooth with a single XRD reflection attributed to the (004) plane of c-axis-orientated epitaxial material

  9. 3D printing PLGA: a quantitative examination of the effects of polymer composition and printing parameters on print resolution

    Science.gov (United States)

    Guo, Ting; Holzberg, Timothy R; Lim, Casey G; Gao, Feng; Gargava, Ankit; Trachtenberg, Jordan E; Mikos, Antonios G; Fisher, John P

    2018-01-01

    In the past few decades, 3D printing has played a significant role in fabricating scaffolds with consistent, complex structure that meet patient-specific needs in future clinical applications. Although many studies have contributed to this emerging field of additive manufacturing, which includes material development and computer-aided scaffold design, current quantitative analyses do not correlate material properties, printing parameters, and printing outcomes to a great extent. A model that correlates these properties has tremendous potential to standardize 3D printing for tissue engineering and biomaterial science. In this study, we printed poly(lactic-co-glycolic acid) (PLGA) utilizing a direct melt extrusion technique without additional ingredients. We investigated PLGA with various lactic acid: glycolic acid (LA:GA) molecular weight ratios and end caps to demonstrate the dependence of the extrusion process on the polymer composition. Micro-computed tomography was then used to evaluate printed scaffolds containing different LA:GA ratios, composed of different fiber patterns, and processed under different printing conditions. We built a statistical model to reveal the correlation and predominant factors that determine printing precision. Our model showed a strong linear relationship between the actual and predicted precision under different combinations of printing conditions and material compositions. This quantitative examination establishes a significant foreground to 3D print biomaterials following a systematic fabrication procedure. Additionally, our proposed statistical models can be applied to couple specific biomaterials and 3D printing applications for patient implants with particular requirements. PMID:28244880

  10. 3D printing PLGA: a quantitative examination of the effects of polymer composition and printing parameters on print resolution.

    Science.gov (United States)

    Guo, Ting; Holzberg, Timothy R; Lim, Casey G; Gao, Feng; Gargava, Ankit; Trachtenberg, Jordan E; Mikos, Antonios G; Fisher, John P

    2017-04-12

    In the past few decades, 3D printing has played a significant role in fabricating scaffolds with consistent, complex structure that meet patient-specific needs in future clinical applications. Although many studies have contributed to this emerging field of additive manufacturing, which includes material development and computer-aided scaffold design, current quantitative analyses do not correlate material properties, printing parameters, and printing outcomes to a great extent. A model that correlates these properties has tremendous potential to standardize 3D printing for tissue engineering and biomaterial science. In this study, we printed poly(lactic-co-glycolic acid) (PLGA) utilizing a direct melt extrusion technique without additional ingredients. We investigated PLGA with various lactic acid:glycolic acid (LA:GA) molecular weight ratios and end caps to demonstrate the dependence of the extrusion process on the polymer composition. Micro-computed tomography was then used to evaluate printed scaffolds containing different LA:GA ratios, composed of different fiber patterns, and processed under different printing conditions. We built a statistical model to reveal the correlation and predominant factors that determine printing precision. Our model showed a strong linear relationship between the actual and predicted precision under different combinations of printing conditions and material compositions. This quantitative examination establishes a significant foreground to 3D print biomaterials following a systematic fabrication procedure. Additionally, our proposed statistical models can be applied to couple specific biomaterials and 3D printing applications for patient implants with particular requirements.

  11. Development of an in-situ multi-component reinforced Al-based metal matrix composite by direct metal laser sintering technique — Optimization of process parameters

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Subrata Kumar, E-mail: subratagh82@gmail.com [Department of Mechanical Engineering, National Institute of Technology Agartala, Tripura 799055 (India); Bandyopadhyay, Kaushik; Saha, Partha [Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)

    2014-07-01

    In the present investigation, an in-situ multi-component reinforced aluminum based metal matrix composite was fabricated by the combination of self-propagating high-temperature synthesis and direct metal laser sintering process. The different mixtures of Al, TiO{sub 2} and B{sub 4}C powders were used to initiate and maintain the self-propagating high-temperature synthesis by laser during the sintering process. It was found from the X-ray diffraction analysis and scanning electron microscopy that the reinforcements like Al{sub 2}O{sub 3}, TiC, and TiB{sub 2} were formed in the composite. The scanning electron microscopy revealed the distribution of the reinforcement phases in the composite and phase identities. The variable parameters such as powder layer thickness, laser power, scanning speed, hatching distance and composition of the powder mixture were optimized for higher density, lower porosity and higher microhardness using Taguchi method. Experimental investigation shows that the density of the specimen mainly depends upon the hatching distance, composition and layer thickness. On the other hand, hatching distance, layer thickness and laser power are the significant parameters which influence the porosity. The composition, laser power and layer thickness are the key influencing parameters for microhardness. - Highlights: • The reinforcements such as Al{sub 2}O{sub 3}, TiC, and TiB{sub 2} were produced in Al-MMC through SHS. • The density is mainly influenced by the material composition and hatching distance. • Hatching distance is the major influencing parameter on porosity. • The material composition is the significant parameter to enhance the microhardness. • The SEM micrographs reveal the distribution of TiC, TiB{sub 2} and Al{sub 2}O{sub 3} in the composite.

  12. Development of an in-situ multi-component reinforced Al-based metal matrix composite by direct metal laser sintering technique — Optimization of process parameters

    International Nuclear Information System (INIS)

    Ghosh, Subrata Kumar; Bandyopadhyay, Kaushik; Saha, Partha

    2014-01-01

    In the present investigation, an in-situ multi-component reinforced aluminum based metal matrix composite was fabricated by the combination of self-propagating high-temperature synthesis and direct metal laser sintering process. The different mixtures of Al, TiO 2 and B 4 C powders were used to initiate and maintain the self-propagating high-temperature synthesis by laser during the sintering process. It was found from the X-ray diffraction analysis and scanning electron microscopy that the reinforcements like Al 2 O 3 , TiC, and TiB 2 were formed in the composite. The scanning electron microscopy revealed the distribution of the reinforcement phases in the composite and phase identities. The variable parameters such as powder layer thickness, laser power, scanning speed, hatching distance and composition of the powder mixture were optimized for higher density, lower porosity and higher microhardness using Taguchi method. Experimental investigation shows that the density of the specimen mainly depends upon the hatching distance, composition and layer thickness. On the other hand, hatching distance, layer thickness and laser power are the significant parameters which influence the porosity. The composition, laser power and layer thickness are the key influencing parameters for microhardness. - Highlights: • The reinforcements such as Al 2 O 3 , TiC, and TiB 2 were produced in Al-MMC through SHS. • The density is mainly influenced by the material composition and hatching distance. • Hatching distance is the major influencing parameter on porosity. • The material composition is the significant parameter to enhance the microhardness. • The SEM micrographs reveal the distribution of TiC, TiB 2 and Al 2 O 3 in the composite

  13. [The effect of technological parameters of wide-band laser cladding on microstructure and sinterability of gradient bioceramics composite coating].

    Science.gov (United States)

    Liu, Qibin; Zhu, Weidong; Zou, Longjiang; Zheng, Min; Dong, Chuang

    2005-12-01

    The gradient bioceramics coating was prepared on the surface of Ti-6Al-4V alloy by using wide-band laser cladding. And the effect of technological parameters of wide-band laser cladding on microstructure and sinterability of gradient bioceramics composite coating was studied. The experimental results indicated that in the circumstances of size of laser doze D and scanning velocity V being fixed, with the increasement of power P, the density of microstructure in bioceramics coating gradually degraded; with the increasement of power P, the pore rate of bioceramics gradually became high. While P = 2.3 KW, the bioceramics coating with dense structure and lower pore rate (5.11%) was obtained; while P = 2.9 KW, the bioceramics coating with disappointing density was formed and its pore rate was up to 21.32%. The microhardness of bioceramics coating demonstrated that while P = 2.3 KW, the largest value of microhardness of bioceramics coating was 1100 HV. Under the condition of our research work, the optimum technological parameters for preparing gradient bioceramics coating by wide-band laser cladding are: P = 2.3 KW, V = 145 mm/min, D = 16 mm x 2 mm.

  14. Iron-borosilicate soft magnetic composites: The correlation between processing parameters and magnetic properties for high frequency applications

    Energy Technology Data Exchange (ETDEWEB)

    Gheiratmand, T., E-mail: t.gheiratmand@yahoo.com; Madaah Hosseini, H.R., E-mail: Madaah@sharif.edu; Seyed Reihani, S.M.

    2017-05-01

    Iron-borosilicate soft magnetic composites are suitable magnetic materials for high temperature and high frequency applications. In this research two different techniques have been applied to fabricate these composites: uniaxial pressing following by sintering and spark plasma sintering. Different processing parameters including the content of borosilicate, the amount of compaction pressure and the size of iron particles have been evaluated through the study of microstructure and magnetic properties. The microstructural observations showed that the borosilicate is distributed on the iron grain boundaries enhancing the resistivity and causing the loss of eddy currents. Increasing the compaction pressure was led to the decrease of electrical resistivity. By increasing the frequency both real and imaginary parts of permeability decreased. The use of higher content of borosilicate resulted in the lower decreasing slop of permeability. Best combination of density, permeability and electrical resistivity was obtained in the sample with 2 wt% of borosilicate. In addition, the densification of powders with fine particles was more difficult than coarse particles due to the inter particles friction and bridging effects. Furthermore, as the particles size increases the size of open porosities before sintering where the borosilicate could aggregate enhances. This could yields to the increase in the electrical resistivity. The high ratio of surface to the volume in the powders with fine particles results in the developing the demagnetizing fields and subsequently, decreasing the permeability. The highest relative density (99.99% of theoretical density) with best distribution of borosilicate was achieved in the composites produced by spark plasma sintering (SPS). The relaxation frequency, obtained from imaginary part of permeability, was found as 340 Hz in the composites made by SPS. - Highlights: • Iron-borosilicate SMC was produced for high temperature and frequency

  15. Composites

    International Nuclear Information System (INIS)

    Kasen, M.B.

    1983-01-01

    This chapter discusses the roles of composite laminates and aggregates in cryogenic technology. Filamentary-reinforced composites are emphasized because they are the most widely used composite materials. Topics considered include composite systems and terminology, design and fabrication, composite failure, high-pressure reinforced plastic laminates, low-pressure reinforced plastics, reinforced metals, selectively reinforced structures, the effect of cryogenic temperatures, woven-fabric and random-mat composites, uniaxial fiber-reinforced composites, composite joints in cryogenic structures, joining techniques at room temperature, radiation effects, testing laminates at cryogenic temperatures, static and cyclic tensile testing, static and cyclic compression testing, interlaminar shear testing, secondary property tests, and concrete aggregates. It is suggested that cryogenic composite technology would benefit from the development of a fracture mechanics model for predicting the fitness-for-purpose of polymer-matrix composite structures

  16. Parameter optimization and evaluation of mechanical and thermal properties of nanographene reinforced Al 6060 surface composite using FSP

    Science.gov (United States)

    Kalyanamanohar, V.; Appalachari, D. Gireesh Chandra

    2018-04-01

    Friction stir processing (FSP) is emerging as a promising technique for making surface composites. FSP can improve surface properties such as hardness, strength, ductility, corrosion resistance, fatigue life and formability without affecting the bulk properties of the material. The literatures reported that FSP can produces very fine equiaxed and homogeneous grain structure for different Al alloys. Al 6060 is heat treatable alloy which has high thermal and electrical properties than remaining Al alloys. Al 6060 is being used where high rate of heat exchange is needed i.e. engine cylinders, heat exchangers etc. As derived from the carbon materials, like graphene and CNTs dissipates heat rapidly that improves the life of the engine cylinders and heat exchangers. In this work, nanographene is reinforced in the Al 6060 using friction stir processing at different rotational speeds, traverse speeds, and at constant load and tool tilt angle. After processed, the effect of process parameters on microstructure of the surface composite was investigated. The SEM studies shows that the FSP produces very fine and homogenous grain structure and it is observed that smaller grain size structure is obtained at lower traverse speed and higher rotational speeds. Significant improvement in ultimate tensile strength(22.9%) and hardness (22.44%) when compared friction stir processed plate at 1400 rotational speed and 20mm/min traverse speed with base Al 6060 plate. Coefficient of thermal expansion test of nanographene reinforced Al 6060 shows 7.33% decrease in its coefficient of thermal expansion as graphene has tendency to reduce the anisotropic nature.

  17. Structural properties and stability of the bcc and omega phases in the Zr-Nb system. Pt. II. Composition dependence of the lattice parameters

    International Nuclear Information System (INIS)

    Grad, G.B.; Guillermet, A.F.; Pieres, J.J.; Cuello, G.J.; Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires; Universidad Nacional del Comahue

    1996-01-01

    For pt.I see Guillermet, A.F., J. Nucl. Mater., vol.218, p.236-46, 1995. This paper deals with the composition dependence of the lattice parameters of the bcc and omega phases of the Zr-Nb system. The experimental part of the work comprises neutron scattering experiments on a Zr-10 at.% Nb alloy in the as-quenched state and after successive aging treatments at 773 K. This new information is combined with an extensive review of the available data, and a detailed analysis is performed of the effects of composition and heat-treatment upon the lattice parameters a Ω and c Ω of the omega phase and the lattice-parameter relations between bcc and omega. A striking behaviour is detected in the variation of a Ω with composition in low-Nb alloys. (orig.)

  18. Theoretical analysis of the influence of defect parameters on photovoltaic performances of composition graded InGaN solar cells

    International Nuclear Information System (INIS)

    Gorge, V.; Migan-Dubois, A.; Djebbour, Z.; Pantzas, K.; Gautier, S.; Moudakir, T.; Suresh, S.; Ougazzaden, A.

    2013-01-01

    Highlights: ► We have modeled a p–i–n InGaN-based solar cell with gradual bandgap layers. ► InGaN defects have been modeled by two band tails and one localized energy level. ► Energetic position and band tail widths have a low effect on device efficiency. ► The localized defect FWHM has a significant impact on performance. ► The efficiency drops radically when the defect density is higher than the P-doping. - Abstract: In this paper, we have used simulations to evaluate the impact of the distribution of electrically active defects on the photovoltaic performances of InGaN-based solar cell. The simulations were carried out using Silvaco's ATLAS software. We have modeled a P-GaN/Grad-InGaN/i-In 0.53 Ga 0.47 N/Grad-InGaN/N-ZnO where Grad-InGaN corresponds to an InGaN layer with a graded composition. This layer is inserted to eliminate the band discontinuities at the interface between InGaN and the GaN and ZnO layers. The defects were modeled through the introduction of band tails and a Gaussian distribution of defects in i-InGaN material. We have evaluated the influence of band tail widths as well as the parameters of the Gaussian distribution (i.e. defect density, mean position and standard deviation) on the short-circuit current, the open-circuit voltage and the fill-factor (efficiency) of the solar cell. These results have allowed us to identify key structural parameters useful for the optimization of InGaN solar cells, as well as to give realistic estimates of the performances of such cells.

  19. Theoretical analysis of the influence of defect parameters on photovoltaic performances of composition graded InGaN solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Gorge, V.; Migan-Dubois, A. [LGEP, UMR 8507, CNRS, SUPELEC, UPMC, Universite Paris-Sud 11, 11 rue Joliot-Curie, Plateau de Moulon, 91192 Gif-sur-Yvette Cedex (France); Djebbour, Z., E-mail: zakaria.djebbour@uvsq.fr [LGEP, UMR 8507, CNRS, SUPELEC, UPMC, Universite Paris-Sud 11, 11 rue Joliot-Curie, Plateau de Moulon, 91192 Gif-sur-Yvette Cedex (France); Department of Physics and Engineering Science, University of Versailles UVSQ, 45 Av. Des Etats Unis, 78035 Versailles (France); Pantzas, K. [Georgia Institute of Technology, GT-Lorraine, 2 rue Marconi, 57 070 Metz (France); UMI 2958 Georgia Tech, CNRS, 2 rue Marconi, 57 070 Metz (France); Gautier, S. [UMI 2958 Georgia Tech, CNRS, 2 rue Marconi, 57 070 Metz (France); LMOPS, UMR 7132, CNRS, University of Metz, Supelec, 2 rue E. Belin, 57 070 Metz (France); Moudakir, T.; Suresh, S. [UMI 2958 Georgia Tech, CNRS, 2 rue Marconi, 57 070 Metz (France); Ougazzaden, A. [Georgia Institute of Technology, GT-Lorraine, 2 rue Marconi, 57 070 Metz (France); UMI 2958 Georgia Tech, CNRS, 2 rue Marconi, 57 070 Metz (France)

    2013-02-01

    Highlights: Black-Right-Pointing-Pointer We have modeled a p-i-n InGaN-based solar cell with gradual bandgap layers. Black-Right-Pointing-Pointer InGaN defects have been modeled by two band tails and one localized energy level. Black-Right-Pointing-Pointer Energetic position and band tail widths have a low effect on device efficiency. Black-Right-Pointing-Pointer The localized defect FWHM has a significant impact on performance. Black-Right-Pointing-Pointer The efficiency drops radically when the defect density is higher than the P-doping. - Abstract: In this paper, we have used simulations to evaluate the impact of the distribution of electrically active defects on the photovoltaic performances of InGaN-based solar cell. The simulations were carried out using Silvaco's ATLAS software. We have modeled a P-GaN/Grad-InGaN/i-In{sub 0.53}Ga{sub 0.47}N/Grad-InGaN/N-ZnO where Grad-InGaN corresponds to an InGaN layer with a graded composition. This layer is inserted to eliminate the band discontinuities at the interface between InGaN and the GaN and ZnO layers. The defects were modeled through the introduction of band tails and a Gaussian distribution of defects in i-InGaN material. We have evaluated the influence of band tail widths as well as the parameters of the Gaussian distribution (i.e. defect density, mean position and standard deviation) on the short-circuit current, the open-circuit voltage and the fill-factor (efficiency) of the solar cell. These results have allowed us to identify key structural parameters useful for the optimization of InGaN solar cells, as well as to give realistic estimates of the performances of such cells.

  20. Composition

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    2011-01-01

    Strategies are open compositions to be realised by improvising musicians. See more about my composition practise in the entry "Composition - General Introduction". Caution: streaming the sound files will in some cases only provide a few minutes' sample. Please DOWNLOAD them to hear them in full...

  1. Composition

    DEFF Research Database (Denmark)

    2014-01-01

    Memory Pieces are open compositions to be realised solo by an improvising musicians. See more about my composition practise in the entry "Composition - General Introduction". Caution: streaming the sound files will in some cases only provide a few minutes' sample. Please DOWNLOAD them to hear them...

  2. Effect of Firing Temperature on the Composition and Structural Parameters of Screen Printed ZrO2 Thick Film Sensors

    Directory of Open Access Journals (Sweden)

    S. J. PATIL

    2010-12-01

    Full Text Available The compositional, morphological and structural properties of ZrO2 thick films prepared by a standard screen printing method and fired between 800 oC to 1000 oC for 2 hours in an air atmosphere. The material characterization was done using X-ray energy dispersive analysis (EDX, X-ray diffraction (XRD and a scanning electron microscope (SEM. The deposited films were polycrystalline in nature having the monoclinic, tetragonal- cubic structure with a preferred orientation along the (1’11 plane. The result shows that the mass % of Zr was found to be 79.10, 82.14 and 82.04 % for firing temperatures of 800, 900 and 1000 0C respectively may be due to the release of excess oxygen. The effect of the firing temperature on structural parameters such as the crystallite size, percentage of phases, texture coefficient, RMSmicrostrain, dislocation density and stacking fault probability have been studied. The results indicate that grain growth can be increased by increasing the firing temperature which is responsible for decreasing the RMSmicrostrain and dislocation density in ZrO2 thick films. The stacking fault probability remains constant for all firing temperatures. The crystallite size changes from 25.71 nm to 30.80 nm with respect to the increase in the firing temperature.

  3. Influence of parameters of mixing of the mortar mixtures on the performance of ornamental composites for facade coating

    Directory of Open Access Journals (Sweden)

    Tkach Evgeniay

    2017-01-01

    Full Text Available Studies have shown that the main physical-mechanical properties of decorative coatings based on colloidal cement systems greatly depend on the homogeneity of the structure of hardened stone, therefore, in the preparation of mortar mixtures were set the task of achieving this target. It is shown that vibrational mix of materials helps to ensure the preparation of mortar mixes with cement-based colloidal systems with a more homogeneous distribution of the components. The efficiency of vibrational mixing was determined by comparing the strength of the mortar mixes based on colloidal cement glue, cooked in vibromaster when the vibration acceleration with the strength of samples prepared in a standard mortar mixer of forced action without vibration. The results of the research confirmed some influence of the mineralogical composition of clinker the cement component of the colloidal material on the effect of vibration treatment solutions. Parameters preparation of the mortar mixtures based on cement colloidal material in a vibratory mixer. Optimum resonant operating frequency of the vibrations, at which is achieved the positive effect of mixing of the mixture is ensured with amplitude 5mm while accelerating 214,8 m/S2 and duration of mixing 60-90s. It is established that vibropressure contributes to the intensification hydration processes to temperature is minus 5 0С

  4. Impact of body composition parameters on clinical outcomes in patients with metastatic castrate-resistant prostate cancer treated with docetaxel.

    Science.gov (United States)

    Cushen, Samantha J; Power, Derek G; Murphy, Kevin P; McDermott, Ray; Griffin, Brendan T; Lim, Marvin; Daly, Louise; MacEneaney, Peter; O' Sullivan, Kathleen; Prado, Carla M; Ryan, Aoife M

    2016-06-01

    Body composition may influence clinical outcomes of certain chemotherapeutic agents. We examined the prognostic significance of skeletal muscle mass and adipose tissue on docetaxel toxicity and overall survival in patients with metastatic castrate resistant prostate cancer (mCRPC). A retrospective review of patients medical records with mCRPC, treated with docetaxel was conducted. Body composition parameters (skeletal muscle mass, muscle attenuation [MA], visceral and subcutaneous adipose tissue) were measured at L3 by computed tomography (CT) and defined using previously established cut points. Toxicity profile was assessed after 3 cycles of the drug and graded according to the National Cancer Institute Common Toxicity Criteria (version 4). Overall survival was analysed. Overall 63 patients, mean age 69 years (SD 8.3), were included. Sarcopenia was present in 47% (n = 30) and of these 26.7% (8/30) were sarcopenic obese. Common toxicities (all grades) observed included fatigue (80.9%), pain (46%), and constipation (34.9%). DLT occurred in 22 (34.9%) patients; of these 10 patients (15.8%) experienced dose reductions and 12 patients (19%) experienced dose terminations. Measurements of adiposity were not predictive of DLT, however 59.1% patients who had a combination of both sarcopenia and low MA experienced DLT compared to 29.3% of patients without sarcopenia and low MA (p = 0.021). Skeletal muscle index and MA were significantly lower in patients who experienced neutropenia (grade I-II) (46.5 cm 2 /m 2 vs. 51.2 cm 2 /m 2 , p = 0.005) compared to their counterparts (24.6 HU vs. 32.2 HU, p = 0.044). Neither sarcopenia nor sarcopenic obesity was associated with overall survival. In multivariate analysis, BMI ≥25 kg/m 2 (HR: 0.349, CI: 0.156-0.782, p = 0.010) was a significant predictor of longer overall survival and both visceral fat index ≥ median 58.7 cm 2 /m 2 (HR: 2.266 CI: 1.066-4.814, p = 0.033) and anaemia (HR: 2.81, CI: 1.297-6.091, p

  5. Laboratory mechanical parameters of composite resins and their relation to fractures and wear in clinical trials-A systematic review.

    Science.gov (United States)

    Heintze, Siegward D; Ilie, Nicoleta; Hickel, Reinhard; Reis, Alessandra; Loguercio, Alessandro; Rousson, Valentin

    2017-03-01

    To evaluate a range of mechanical parameters of composite resins and compare the data to the frequency of fractures and wear in clinical studies. Based on a search of PubMed and SCOPUS, clinical studies on posterior composite restorations were investigated with regard to bias by two independent reviewers using Cochrane Collaboration's tool for assessing risk of bias in randomized trials. The target variables were chipping and/or fracture, loss of anatomical form (wear) and a combination of both (summary clinical index). These outcomes were modelled by time and material in a linear mixed effect model including random study and experiment effects. The laboratory data from one test institute were used: flexural strength, flexural modulus, compressive strength, and fracture toughness (all after 24-h storage in distilled water). For some materials flexural strength data after aging in water/saliva/ethanol were available. Besides calculating correlations between clinical and laboratory outcomes, we explored whether a model including a laboratory predictor dichotomized at a cut-off value better predicted a clinical outcome than a linear model. A total of 74 clinical experiments from 45 studies were included involving 31 materials for which laboratory data were also available. A weak positive correlation between fracture toughness and clinical fractures was found (Spearman rho=0.34, p=0.11) in addition to a moderate and statistically significant correlation between flexural strength and clinical wear (Spearman rho=0.46, p=0.01). When excluding those studies with "high" risk of bias (n=18), the correlations were generally weaker with no statistically significant correlation. For aging in ethanol, a very strong correlation was found between flexural strength decrease and clinical index, but this finding was based on only 7 materials (Spearman rho=0.96, p=0.0001). Prediction was not consistently improved with cutoff values. Correlations between clinical and laboratory

  6. Study of elastic and thermal parameters of a composite material fluoro-plastic - thermo-exfoliated graphite by photothermoacoustic method

    International Nuclear Information System (INIS)

    Kozachenko, V.V.; Kucherov, I.Ya.; Revo, S.L.

    2004-01-01

    Full text: The composite materials (CM) with success are widely used in a science and in an industry. From the practical point of view important for CM the mechanical and thermal properties are. Therefore, study of these properties for them is the important problem. At change of a temperature state of materials of their property in many cases are featured by combinations of elastic and thermal parameters E/1-σ=E n and χ/ρc=D T , where E, -σ, ρ and c are the Young's modulus, Poisson's ratio, thermal conductivity coefficient, density and specific heat of materials, respectively. Now for examination of substances in various aggregate states has received development a photothermoacoustic (PTA) method. As shown in this work, use a PTA method with piezoelectric detection of a PTA signal from a layered plate, under certain conditions, allows immediately determining the reduced Young's modulus E n and thermal diffusivity D T . Therefore, the purpose of this work was study the PTA effect with piezoelectric detection of an informative signal from CM. Were explored steel-copper CM such as 'sandwich' and fluoro plastic-thermo exfoliated graphite FP-TEG CM. Explored triplex structure as a plate made of a CM sample and a two-layer piezoelectric transducer. The surface of a CM is uniformly irradiated with a modulated light flux. The sample is heated and the thermal waves are generated. In the sample, the temperature field of thermal waves generates, due to the thermoelastic effect, acoustic vibration and waves that are registered by a piezoelectric. The rather low frequencies of modulation are considered, at which length of ultrasonic waves is much more than the reference sizes of structure (quasi-static approach). The amplitudes ratio and phase difference of voltages oscillations taken from separate layer of piezoelectric transducer, as functions of physical and geometrical parameters of structure and a frequency of a light flux modulation is found. Experimentally the

  7. Milk yield and composition, dry matter intake and blood parameters of Holstein cows fed ensiled apple pomace co-ensiled with broiler litter

    DEFF Research Database (Denmark)

    Osman Azizi, Osman; Karimi, Shahram; Sadeghi, Ghorbanali

    2014-01-01

    The present study was carried out to evaluate the effects of ensiled mixed apple pomace and broiler litter (EAPBL) on milk yield (MY) and composition, dry matter intake (DMI) and blood parameters at early lactation cow. Four multiparous early-lactating Holstein dairy cows were used in a 4×4 Latin...

  8. Impact of Material and Architecture Model Parameters on the Failure of Woven Ceramic Matrix Composites (CMCs) via the Multiscale Generalized Method of Cells

    Science.gov (United States)

    Liu, Kuang C.; Arnold, Steven M.

    2011-01-01

    It is well known that failure of a material is a locally driven event. In the case of ceramic matrix composites (CMCs), significant variations in the microstructure of the composite exist and their significance on both deformation and life response need to be assessed. Examples of these variations include changes in the fiber tow shape, tow shifting/nesting and voids within and between tows. In the present work, the effects of many of these architectural parameters and material scatter of woven ceramic composite properties at the macroscale (woven RUC) will be studied to assess their sensitivity. The recently developed Multiscale Generalized Method of Cells methodology is used to determine the overall deformation response, proportional elastic limit (first matrix cracking), and failure under tensile loading conditions. The macroscale responses investigated illustrate the effect of architectural and material parameters on a single RUC representing a five harness satin weave fabric. Results shows that the most critical architectural parameter is weave void shape and content with other parameters being less in severity. Variation of the matrix material properties was also studied to illustrate the influence of the material variability on the overall features of the composite stress-strain response.

  9. Effect of spirulina food supplement on blood morphological parameters, biochemical composition and on the immune function of sportsmen

    Directory of Open Access Journals (Sweden)

    K Milasius

    2009-07-01

    Full Text Available Of highest biological value are natural concentrates of optimally combined substances produced by nature. One of food supplements of this kind is dietary Spirulina produced by the Tianshi firm (China. It is a most rationally balanced food supplement of a high biological value; it satisfies the needs of the whole body, including its immune system. The aim of the current work was to assess the effect of the multicomponent natural food supplement Spirulina on the physical development, blood morphological, biochemical picture and immune function of sportsmen. Materials and Methods: The study cohort comprised 12 high performance sportsmen (age 20-22 years. They were using tablets of Spirulina, a dietary product for 14 days. Physical development was determined with the aid of standard methods. The general blood picture was analyzed with the aid of a Micros-60 hematological analyzer (company ABX DIAGNOSTICS, France. Lymphocytes and their subsets were analysed by flow cytometery (FACSCalibur, Becton Dickinson Immunocytometry Systems (BDIS, USA and the absolute and percentage values were calculated. To evaluate immune function lymphocyte blasttransformation response to mitogens was studied. Results: Investigations carried out on endurance-training sportsmen showed that a 14-d administration of Spirulina exerted a positive effect on blood morphological composition indices and its biochemical changes. The results of our study confirm the positive effect of Spirulina food supplement on the quantitative parameters of immune system. Part of the study cohort after weeks showed a tendency of normalizing CD3 , CD3 CD4 lympocite count: positive changes were still present two weeks following the interruption of Spirulina intake

  10. Genetic parameters and genetic trends in the Chinese × European Tiameslan composite pig line. II. Genetic trends

    Directory of Open Access Journals (Sweden)

    Legault Christian

    2000-01-01

    Full Text Available Abstract The Tiameslan line was created between 1983 and 1985 by mating Meishan × Jiaxing crossbred Chinese boars with sows from the Laconie composite male line. The Tiameslan line has been selected since then on an index combining average backfat thickness (ABT and days from 20 to 100 kg (DT. Direct and correlated responses to 11 years of selection were estimated using BLUP methodology applied to a multiple trait animal model. A total of 11 traits were considered, i.e.: ABT, DT, body weight at 4 (W4w, 8 (W8w and 22 (W22w weeks of age, teat number (TEAT, number of good teats (GTEAT, total number of piglets born (TNB, born alive (NBA and weaned (NW per litter, and birth to weaning survival rate (SURV. Performance data from a total of 4 881 males and 4 799 females from 1 341 litters were analysed. The models included both direct and maternal effects for ABT, W4w and W8w. Male and female performances were considered as different traits for W22w, DT and ABT. Genetic parameters estimated in another paper (Zhang et al., Genet. Sel. Evol. 32 (2000 41-56 were used to perform the analyses. Favourable phenotypic (ΔP and direct genetic trends (ΔGd were obtained for post-weaning growth traits and ABT. Trends for maternal effects were limited. Phenotypic and genetic trends were larger in females than in males for ABT (e.g. ΔGd = -0.48 vs. -0.38 mm/year, were larger in males for W22w (ΔGd = 0.90 vs. 0.58 kg/year and were similar in both sexes for DT (ΔGd = -0.54 vs. -0.55 day/year. Phenotypic and genetic trends were slightly favourable for W4w, W8w, TEAT and GTEAT and close to zero for reproductive traits.

  11. The Potential Impact of Satellite-Retrieved Cloud Parameters on Ground-Level PM2.5 Mass and Composition

    Science.gov (United States)

    Belle, Jessica H.; Chang, Howard H.; Wang, Yujie; Hu, Xuefei; Lyapustin, Alexei; Liu, Yang

    2017-01-01

    Satellite-retrieved aerosol optical properties have been extensively used to estimate ground-level fine particulate matter (PM2.5) concentrations in support of air pollution health effects research and air quality assessment at the urban to global scales. However, a large proportion, approximately 70%, of satellite observations of aerosols are missing as a result of cloud-cover, surface brightness, and snow-cover. The resulting PM2.5 estimates could therefore be biased due to this non-random data missingness. Cloud-cover in particular has the potential to impact ground-level PM2.5 concentrations through complex chemical and physical processes. We developed a series of statistical models using the Multi-Angle Implementation of Atmospheric Correction (MAIAC) aerosol product at 1 km resolution with information from the MODIS cloud product and meteorological information to investigate the extent to which cloud parameters and associated meteorological conditions impact ground-level aerosols at two urban sites in the US: Atlanta and San Francisco. We find that changes in temperature, wind speed, relative humidity, planetary boundary layer height, convective available potential energy, precipitation, cloud effective radius, cloud optical depth, and cloud emissivity are associated with changes in PM2.5 concentration and composition, and the changes differ by overpass time and cloud phase as well as between the San Francisco and Atlanta sites. A case-study at the San Francisco site confirmed that accounting for cloud-cover and associated meteorological conditions could substantially alter the spatial distribution of monthly ground-level PM2.5 concentrations.

  12. The Potential Impact of Satellite-Retrieved Cloud Parameters on Ground-Level PM2.5 Mass and Composition

    Directory of Open Access Journals (Sweden)

    Jessica H. Belle

    2017-10-01

    Full Text Available Satellite-retrieved aerosol optical properties have been extensively used to estimate ground-level fine particulate matter (PM2.5 concentrations in support of air pollution health effects research and air quality assessment at the urban to global scales. However, a large proportion, ~70%, of satellite observations of aerosols are missing as a result of cloud-cover, surface brightness, and snow-cover. The resulting PM2.5 estimates could therefore be biased due to this non-random data missingness. Cloud-cover in particular has the potential to impact ground-level PM2.5 concentrations through complex chemical and physical processes. We developed a series of statistical models using the Multi-Angle Implementation of Atmospheric Correction (MAIAC aerosol product at 1 km resolution with information from the MODIS cloud product and meteorological information to investigate the extent to which cloud parameters and associated meteorological conditions impact ground-level aerosols at two urban sites in the US: Atlanta and San Francisco. We find that changes in temperature, wind speed, relative humidity, planetary boundary layer height, convective available potential energy, precipitation, cloud effective radius, cloud optical depth, and cloud emissivity are associated with changes in PM2.5 concentration and composition, and the changes differ by overpass time and cloud phase as well as between the San Francisco and Atlanta sites. A case-study at the San Francisco site confirmed that accounting for cloud-cover and associated meteorological conditions could substantially alter the spatial distribution of monthly ground-level PM2.5 concentrations.

  13. The Influence of Pressure Die Casting Parameters on the Mechanical Properties of AlSi11/10 Vol.% SiC Composite

    Directory of Open Access Journals (Sweden)

    Konopka Z.

    2014-03-01

    Full Text Available The paper presents the method of preparing a composite slurry composed of AlSi11 alloy matrix and 10 vol.% of SiC particles, as well as the method of its high-pressure die casting and the measurement results concerning the tensile strength, the yield point, the elongation and hardness of the obtained composite. Composite castings were produced at various values of the piston velocity in the second stage of injection, diverse intensification pressure values, and various injection gate width values. There were found the regression equations describing the change of mechanical properties of the examined composite as a function of pressure die casting process parameters. The conclusion gives the analysis and the interpretation of the obtained results.

  14. Effect of Cutting Parameters on Thrust Force and Surface Roughness in Drilling of Al-2219/B4C/Gr Metal Matrix Composites

    Science.gov (United States)

    Ravindranath, V. M.; Basavarajappa, G. S. Shiva Shankar S.; Suresh, R.

    2016-09-01

    In aluminium matrix composites, reinforcement of hard ceramic particle present inside the matrix which causes tool wear, high cutting forces and poor surface finish during machining. This paper focuses on effect of cutting parameters on thrust force, surface roughness and burr height during drilling of MMCs. In the present work, discuss the influence of spindle speed and feed rate on drilling the pure base alloy (Al-2219), mono composite (Al- 2219+8% B4C) and hybrid composite (Al-2219+8%B4C+3%Gr). The composites were fabricated using liquid metallurgy route. The drilling experiments were conducted by CNC machine with TiN coated HSS tool, M42 (Cobalt grade) and carbide tools at various spindle speeds and feed rates. The thrust force, surface roughness and burr height of the drilled hole were investigated in mono composite and hybrid composite containing graphite particles, the experimental results show that the feed rate has more influence on thrust force and surface roughness. Lesser thrust force and discontinuous chips were produced during machining of hybrid composites when compared with mono and base alloy during drilling process. It is due to solid lubricant property of graphite which reduces the lesser thrust force, burr height and lower surface roughness. When machining with Carbide tool at low feed and high speeds good surface finish was obtained compared to other two types of cutting tool materials.

  15. Composition

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    2014-01-01

    Cue Rondo is an open composition to be realised by improvising musicians. See more about my composition practise in the entry "Composition - General Introduction". Caution: streaming the sound/video files will in some cases only provide a few minutes' sample, or the visuals will not appear at all....... Please DOWNLOAD them to see/hear them in full length! This work is licensed under a Creative Commons "by-nc" License. You may for non-commercial purposes use and distribute it, performance instructions as well as specially designated recordings, as long as the author is mentioned. Please see http...

  16. Composition and structure of the larval fish community related to environmental parameters in a tropical estuary impacted by climate change

    Science.gov (United States)

    Sloterdijk, Hans; Brehmer, Patrice; Sadio, Oumar; Müller, Hanno; Döring, Julian; Ekau, Werner

    2017-10-01

    Mangrove ecosystems have long been considered essential habitats and are commonly viewed and referred to as "nursery areas". They are highly sensitive to climate change, and environmental transformations in these ecosystems are expected. The Sine Saloum estuary is a case of a system affected by global climate change where reduced precipitation and temperature increase have resulted in an inversion of the salinity gradient. Within the estuary, the composition and structure of the larval fish community related to environmental parameters were investigated using neuston and ring trawl nets. Larval fishes were sampled at 16 stations distributed along a salinity and distance-to-the-sea gradient during four field campaigns (November 2013, February, June, and August 2014) covering an annual cycle. This is the first study documenting the spatial and temporal assemblages of fish larvae in an inverse estuary. The total of 41 taxa representing 24 families and 34 genus identified in this study was lower than that of other tropical estuaries. Clupeidae spp. was the dominant taxon, accounting for 28.9% of the total number of fish larvae caught, followed by Gerreidae spp. (21.1%), Hyporamphus picarti (18.8%), Diplodus bellottii (8.9%), Hypleurochilus langi (4.8%), Mugilidae spp. (4.4%), and Gobiidae sp.1 (3.5%). A total of 20 taxa were recorded within the upper estuary region, whereas 29 and 37 taxa were observed in the middle and lower reaches, respectively. While larval fish were captured at all sites and during all seasons, abundances and richness decreased with increasing salinity. Larval fish assemblages also showed a clear vertical structure corresponding to three distinct water strata. Salinity, water temperature, and dissolved oxygen were the variables that best explained the spatial and temporal differences in larval fish assemblages. It is difficult to forecast the future situation for this system but so far, compared to other mangrove estuarine systems, we have

  17. Influence of Reinforcement Parameters and Ageing Time on Mechanical Behavior of Novel Al2024/SiC/Red Mud Composites Using Response Surface Methodology

    Science.gov (United States)

    Singh, Jaswinder; Chauhan, Amit

    2017-12-01

    This study investigates the mechanical behavior of aluminum 2024 matrix composites reinforced with silicon carbide and red mud particles. The hybrid reinforcements were successfully incorporated into the alloy matrix using the stir casting process. An orthogonal array based on Taguchi's technique was used to acquire experimental data for mechanical properties (hardness and impact energy) of the composites. The analysis of variance (ANOVA) and response surface methodology (RSM) techniques were used to evaluate the influence of test parameters (reinforcement ratio, particle size and ageing time). The morphological analysis of the surfaces (fractured during impact tests) was conducted to identify the failure mechanism. Finally, a confirmation experiment was performed to check the adequacy of the developed model. The results indicate that the ageing time is the most effective parameter as far as the hardness of the hybrid composites is concerned. It has also been revealed that red mud wt.% has maximum influence on the impact energy characteristics of the hybrid composites. The study concludes that Al2024/SiC/red mud hybrid composites possess superior mechanical performance in comparison to pure alloy under optimized conditions.

  18. The Optimum Processing Parameter of Carbon Nano tubes and Thermoplastic Natural Rubber (NR/LNR/LLDPE) Composites Based on Tensile Properties

    International Nuclear Information System (INIS)

    Hazwani Halim; Syed Yusainee Syed Yahya; Sahrim Ahmad; Tarawneh, M.A.; Shamsul Bahri, A.R.

    2011-01-01

    In this study, the exact processing parameter including mixing time, rotor speed and temperature of CNTs and TPNR (NR/LNR/LLDPE) composite has been examined using tensile properties. To prepare the composite, the matrix NR/LLDPE will compatabilized using liquid natural rubber (LNR) with 40 % NR, 10 % LNR and 50 % LLDPE. Then, 2 % CNTs will be incorporated into the matrix using different processing temperature, rotor speed and mixing time. For the temperature, different temperature that used are 135, 140, 145, 150 and 155 degree and for the rotor speed 45, 50, 55, 60 and 65 rpm have been used. As for the mixing time, five different time have been investigated which is 9 min,11 min, 13 min, 15 min and 17 min. The results for Young's modulus and elongation at break show that there is the maximum increment for the composite that have been prepared using 140 degree Celsius, 55 rpm and 13 min. However when the temperature has been increased, both of these properties has been decreased. Based on these results we can conclude that the optimum processing parameter for these CNTs composite is quite similar with the composite of the matrix (TPNR) itself. (author)

  19. Optimization of friction stir welding process parameters to maximize tensile strength of stir cast AA6061-T6/AlNp composite

    International Nuclear Information System (INIS)

    Ashok Kumar, B.; Murugan, N.

    2014-01-01

    Highlights: • AA6061/AlN p cast composite was welded by FSW process. • Regression models were developed to predict UTS and elongation of the FS welded joint. • FS welded joint using the optimized parameters exhibited maximum UTS and joint efficiency. • Defect free weld joint was obtained with optimized parameters value. - Abstract: Aluminium Matrix Composites (AMCs) reinforced with particulate form of reinforcement has replaced monolithic alloys in many engineering industries due to its superior mechanical properties and tailorable thermal and electrical properties. As aluminium nitride (AlN) has high specific strength, high thermal conductivity, high electrical resistivity, low dielectric constant, low coefficient of thermal expansion and good compatibility with aluminium alloy, Al/AlN composite is extensively used in electronic packaging industries. Joining of AMCs is unavoidable in many engineering applications. Friction Stir Welding (FSW) is one of the most suitable welding process to weld the AMCs reinforced with particulate form of ceramics without deteriorating its superior mechanical properties. An attempt has been made to develop regression models to predict the Ultimate Tensile Strength (UTS) and Percent Elongation (PE) of the friction stir welded AA6061 matrix composite reinforced with aluminium nitride particles (AlN p ) by correlating the significant parameters such as tool rotational speed, welding speed, axial force and percentage of AlN p reinforcement in the AA6061 matrix. Statistical software SYSTAT 12 and statistical tools such as analysis of variance (ANOVA) and student’s t test, have been used to validate the developed models. It was observed from the investigation that these factors independently influenced the UTS and PE of the friction stir welded composite joints. The developed regression models were optimized to maximize UTS of friction stir welded AA6061/AlN p composite joints

  20. Composite multi-parameter ranking of real and virtual compounds for design of MC4R agonists: renaissance of the Free-Wilson methodology.

    Science.gov (United States)

    Nilsson, Ingemar; Polla, Magnus O

    2012-10-01

    Drug design is a multi-parameter task present in the analysis of experimental data for synthesized compounds and in the prediction of new compounds with desired properties. This article describes the implementation of a binned scoring and composite ranking scheme for 11 experimental parameters that were identified as key drivers in the MC4R project. The composite ranking scheme was implemented in an AstraZeneca tool for analysis of project data, thereby providing an immediate re-ranking as new experimental data was added. The automated ranking also highlighted compounds overlooked by the project team. The successful implementation of a composite ranking on experimental data led to the development of an equivalent virtual score, which was based on Free-Wilson models of the parameters from the experimental ranking. The individual Free-Wilson models showed good to high predictive power with a correlation coefficient between 0.45 and 0.97 based on the external test set. The virtual ranking adds value to the selection of compounds for synthesis but error propagation must be controlled. The experimental ranking approach adds significant value, is parameter independent and can be tuned and applied to any drug discovery project.

  1. Multi-response optimization of process parameters using Taguchi method and grey relational analysis during turning AA 7075/SiC composite in dry and spray cooling environments

    Directory of Open Access Journals (Sweden)

    P. C. Mishra

    2015-09-01

    Full Text Available Turning experiments were carried out on AA 7075/SiC composite workpiece in dry and spray cooling environments based on L16 Taguchi design of experiments. Multiple performance optimization of process parameters was performed using grey relational analysis. The performance characteristics considered were average surface roughness, cutting tool temperature and material removal rate. Uncoated carbide inserts were used for machining the workpiece in a high speed precision lathe. A grey relational grade obtained from grey relational analysis was used to optimize the process parameters. Optimal combination of process parameters was then determined by the Taguchi method using the grey relational grade as the performance index. Experimental results indicated that the turning in spray cooling environment was beneficial compared to that in dry environment for the quality response characteristics under consideration. Analysis of variance showed that feed was the most significant parameter for the multiple performance characteristics during turning in both the environments.

  2. Estimation of the parameters of cytotoxicity of fullerene C60 and C60-containing composites in vitro

    International Nuclear Information System (INIS)

    Priluts'ka, S.V.; Grinyuk, Yi.Yi.; Golub, O.A.; Matishevs'ka, O.P.

    2006-01-01

    The influence of fullerene C 60 and C 60 -containing composites (on the basis of aminopropylaerosyl (ApA)) on the stability of erythrocytes to acid haemolysis and the viability of thymocytes, ascite forms of Erlich and leucosis L1210 cells is studied. The obtained results indicate the possibility to use ApA as a matrix for conjugation with other elements and for the further biological studies of composites photosensitizing the effect

  3. Effect of turning parameters on surface roughness of A356/5% SiC composite produced by electromagnetic stir casting

    Energy Technology Data Exchange (ETDEWEB)

    Dwivedi, S. P.; Kumar, Sudhir; Kumar, Ajay [Noida Institute of Engineering Technology, U.P (India)

    2012-12-15

    In the present investigation, A356 alloy 5 wt% SiC composite is fabricated by electromagnetic stir casting process. An attempt has been made to investigate the effect of CNC lathe process parameters like cutting speed, depth of cut, and feed rate on surface roughness during machining of A356 alloy 5 wt% SiC particulate metal-matrix composites in dry condition. Response surface methodology (Box Behnken Method) is chosen to design the experiments. The results reveal that cutting speed increases surface roughness decreases, whereas depth of cut and feed increase surface roughness increase. Optimum values of speed (190 m/min), feed (0.14 mm/rev) and depth of cut (0.20 mm) during turning of A356 alloy 5 wt% SiC composites to minimize the surface roughness (3.15>m) have been find out. The mechanical properties of A356 alloy 5 wt% SiC were also analyzed.

  4. Correlations Between Bone Mechanical Properties and Bone Composition Parameters in Mouse Models of Dominant and Recessive Osteogenesis Imperfecta and the Response to Anti-TGF-β Treatment.

    Science.gov (United States)

    Bi, Xiaohong; Grafe, Ingo; Ding, Hao; Flores, Rene; Munivez, Elda; Jiang, Ming Ming; Dawson, Brian; Lee, Brendan; Ambrose, Catherine G

    2017-02-01

    Osteogenesis imperfecta (OI) is a group of genetic disorders characterized by brittle bones that are prone to fracture. Although previous studies in animal models investigated the mechanical properties and material composition of OI bone, little work has been conducted to statistically correlate these parameters to identify key compositional contributors to the impaired bone mechanical behaviors in OI. Further, although increased TGF-β signaling has been demonstrated as a contributing mechanism to the bone pathology in OI models, the relationship between mechanical properties and bone composition after anti-TGF-β treatment in OI has not been studied. Here, we performed follow-up analyses of femurs collected in an earlier study from OI mice with and without anti-TGF-β treatment from both recessive (Crtap -/- ) and dominant (Col1a2 +/P.G610C ) OI mouse models and WT mice. Mechanical properties were determined using three-point bending tests and evaluated for statistical correlation with molecular composition in bone tissue assessed by Raman spectroscopy. Statistical regression analysis was conducted to determine significant compositional determinants of mechanical integrity. Interestingly, we found differences in the relationships between bone composition and mechanical properties and in the response to anti-TGF-β treatment. Femurs of both OI models exhibited increased brittleness, which was associated with reduced collagen content and carbonate substitution. In the Col1a2 +/P.G610C femurs, reduced hydroxyapatite crystallinity was also found to be associated with increased brittleness, and increased mineral-to-collagen ratio was correlated with increased ultimate strength, elastic modulus, and bone brittleness. In both models of OI, regression analysis demonstrated that collagen content was an important predictor of the increased brittleness. In summary, this work provides new insights into the relationships between bone composition and material properties in

  5. Homogenization-based interval analysis for structural-acoustic problem involving periodical composites and multi-scale uncertain-but-bounded parameters.

    Science.gov (United States)

    Chen, Ning; Yu, Dejie; Xia, Baizhan; Liu, Jian; Ma, Zhengdong

    2017-04-01

    This paper presents a homogenization-based interval analysis method for the prediction of coupled structural-acoustic systems involving periodical composites and multi-scale uncertain-but-bounded parameters. In the structural-acoustic system, the macro plate structure is assumed to be composed of a periodically uniform microstructure. The equivalent macro material properties of the microstructure are computed using the homogenization method. By integrating the first-order Taylor expansion interval analysis method with the homogenization-based finite element method, a homogenization-based interval finite element method (HIFEM) is developed to solve a periodical composite structural-acoustic system with multi-scale uncertain-but-bounded parameters. The corresponding formulations of the HIFEM are deduced. A subinterval technique is also introduced into the HIFEM for higher accuracy. Numerical examples of a hexahedral box and an automobile passenger compartment are given to demonstrate the efficiency of the presented method for a periodical composite structural-acoustic system with multi-scale uncertain-but-bounded parameters.

  6. The influence of different parameters on the discharge capacity and cycling performance of an S/C-composite cathode

    OpenAIRE

    Eberle, Anna-Marietta

    2017-01-01

    Lithium Sulfur batteries are thought to be the next generation energy storage device, because of their high theoretical capacity and energy density. At the moment, their practical application is hindered by several issues, for example fast degradation, low Sulfur (S) utilization or the often too low S loadings to give high areal capacities. Here, a Sulfur/Carbon-composite (S/C-composite) is introduced, which can be synthesised by an easy bottom-up approach with a high S-content in the resulti...

  7. Effect of wear parameters on dry sliding behavior of Fly Ash/SiC particles reinforced AA 2024 hybrid composites

    Science.gov (United States)

    Bhaskar Kurapati, Vijaya; Kommineni, Ravindra

    2017-09-01

    In the present work AA 2024 alloy reinforced with mixtures of SiC and Fly Ash (FA) particles of 70 µm (5, 10 and 15 wt. %) are fabricated using the stir casting method. Both reinforcements are added in equal weight proportions. The wear test specimens are prepared from both the alloy and composite castings in the dimensions of Ф 4 mm and 30 mm lengths by the wire cut EDM process. The dry sliding wear properties of the prepared composites at room temperature are estimated by pin-on-disc wear testing equipment. The wear characteristics of the composites are studied by conducting the dry sliding wear test over loads of 0.5 Kgf, 1.0 Kgf, 1.5 Kgf, a track diameter of 60 mm and sliding times of 15 min, 30 min, 45min. The experimental results shows that the wear decreases with an increase in the weight percentage of FA and SiC particles in the matrix. Additionally wear increases with an increase in load and sliding time. Further, it is found that the wear resistance of the AA2024-Hybrid composites is higher than that of the AA2024 matrix.

  8. Experimental assessment of the influence of welding process parameters on Lamb wave transmission across ultrasonically welded thermoplastic composite joints

    Science.gov (United States)

    Ochôa, Pedro; Fernandez Villegas, Irene; Groves, Roger M.; Benedictus, Rinze

    2018-01-01

    One of the advantages of thermoplastic composites relative to their thermoset counterparts is the possibility of assembling components through welding. Ultrasonic welding in particular is very promising for industrialization. However, uncertainty in the fatigue and fracture behaviour of composites is still an obstacle to the full utilisation of these materials. Health monitoring is then of vital importance, and Lamb wave techniques have been widely recognised as some of the most promising approaches for that end. This paper presents the first experimental study about the influence of welding travel on the transmission of Lamb waves across ultrasonically welded thermoplastic composite joints in single-lap configuration. The main aim of this research is to start to understand how guided waves interact with the internal structure of ultrasonic welds, so that benign, manufacturing-related structural features can be distinguished from damaging ones in signal interpretation. The power transmission coefficient and the correlation coefficient proved to be suitable for analysing the wave propagation phenomena, allowing quantitative identification of small variations of weld-line thickness and intermolecular diffusion at the weld interface. The conclusions are used to develop a tentative damage detection criterion which can later on assist the design of a Lamb wave based structural health monitoring system for thermoplastic composite structures. The Lamb wave test results are backed up by phased-array inspections, which also provide some extra insight on the internal structure of ultrasonic welds.

  9. A Randomized Controlled Trial of Two Different Macronutrient Profiles on Weight, Body Composition and Metabolic Parameters in Obese Adolescents Seeking Weight Loss.

    Directory of Open Access Journals (Sweden)

    Helen Truby

    Full Text Available Adolescent obesity is difficult to treat and the optimal dietary pattern, particularly in relation to macronutrient composition, remains controversial. This study tested the effect of two structured diets with differing macronutrient composition versus control, on weight, body composition and metabolic parameters in obese adolescents.A randomized controlled trial conducted in a children's hospital.Eighty seven obese youth (means: age 13.6 years, BMI z-score 2.2, waist: height ratio 0.65, 69% female completed a psychological preparedness program and were then randomized to a short term 'structured modified carbohydrate' (SMC, 35% carbohydrate; 30% protein; 35% fat, n = 37 or a 'structured low fat' (SLF, 55% carbohydrate; 20% protein; 25% fat, n = 36 or a wait listed control group (n = 14. Anthropometric, body composition and biochemical parameters were measured at randomization and after 12 weeks, and analyzed under the intention to treat principle using analysis of variance models.After 12 weeks, data was collected from 79 (91% participants. BMI z-scores were significantly lower in both intervention groups compared to control after adjusting for baseline values, SLF vs. control, mean difference = -0.13 (95%CI = -0.18, -0.07, P<0.001; SMC vs. control, -0.14 (-0.19, -0.09, P<0.001, but there was no difference between the two intervention diet groups: SLF vs. SMC, 0.00 (-0.05, 0.04, P = 0.83.Both dietary patterns resulted in similar changes in weight, body composition and metabolic improvements compared to control. The use of a structured eating system which allows flexibility but limited choices can assist in weight change and the rigid application of a low fat eating pattern is not exclusive in its efficacy.International Clinical Trials Registry ISRCTN49438757.

  10. Superconducting properties, chemical compositions, and lattice parameters of Pb-, Sn- and (Pb1-xSnx)Mo6S8

    International Nuclear Information System (INIS)

    Sadakata, N.; Corderman, R.; Asano, T.; Cox, D.; Suenaga, M.; Foner, S.; McNiff, E.J. Jr.

    1991-01-01

    The values of critical temperatures for alloys of Pb- and SnMo 6 S 8 were shown to be lower than those of the respective pure Chevrel phases. Chemical compositional analysis of the compounds revealed that the decreased T c in the alloys are due to the off-stoichiometric compositions in the alloys. Although alloying slightly increased the values of the upper critical field H c2 over that for PbMo 6 S 8 , the H c2 values for these specimens were substantially lower than those which have been reported for PbMo 6 S 8 . Possible causes for these depressed values of H c2 are discussed

  11. Effect of processing parameters on Cu-Co-Fe-based diamond impregnated metal matrix composite for stone cutting

    International Nuclear Information System (INIS)

    Mawani, K.; Shahid, M.; Arshad, S.N.; Hasaini, M.H.; Khan, B.S.

    2005-01-01

    Diamond Impregnated Metal Matrix Composites (DIMMC), manufactured by powder metallurgy route, playa major role in stone cutting tool industry. Unfortunately, these diamond tools are not manufactured locally. Our industry relies heavily on the import of these diamond tools to meet the local demand. This study was undertaken as a first step towards indigenous development of these diamond tools. Most of the diamond tools exist in the form of a composite structure with diamond grits embedded in a metallic matrix. This paper investigates the effect of various processing variables on the properties of DIMMC. Effect of pressure on the compaction behavior, sintering time and temperature has been investigated. Relatively better homogeneity has been observed with dry mixing of individual powders using zinc stearate as lubricant compared to wet mixing. A linear increase in green density has been found by increasing compaction pressure up to 400 MPa. (author)

  12. Effect of Material Parameters on Steady State Creep in a Thick Composite Cylinder Subjected to Internal Pressure

    Directory of Open Access Journals (Sweden)

    Tejeet Singh

    2009-12-01

    Full Text Available The steady state creep in Al- SiCP composite cylinder subjected to internal pressure was investigated. The creep behavior of the material were described by threshold stress based creep law by assuming a stress exponent of 5. The effect of size and content of the reinforcement (SiCP , and operating temperature on the stresses and strain rates in the composite cylinder were investigated. The stresses in the cylinder did not have significant variation with varying size and content of the reinforcement, and operating temperature. However, the tangential as well as radial strain rates in the cylinder could be reduced to a significant extent by decreasing size of SiCP, increasing the content of SiCP and decreasing operating temperature.

  13. The Natural Aging Effect on Hardenability in Al-Mg-Si: A Complex Interaction between Composition and Heat Treatment Parameters

    Directory of Open Access Journals (Sweden)

    Alex Poznak

    2018-05-01

    Full Text Available The technological relevance of Al-Mg-Si alloys has been rapidly growing over the last decade. Of particular interest to current and future applications is the problematic negative effect of prior natural aging on subsequent artificial age hardening. The influence of natural aging is dependent on both processing and compositional variables and has origins that are far from well-understood. This work examines the hardenability of 6000 series alloys under a wide range of conditions, paying particular attention to the natural aging effect. Experimental variables include alloy composition (Mg + Si, Mg/Si, cooling rate after solutionization, and duration of prior natural aging. Hardenability was evaluated with full hardness and conductivity aging curves for each condition, as well as select Transmission Electron Microscopy (TEM. Results are discussed based on the actions of naturally aged solute clusters during artificial aging. In particular, a complex interaction between vacancy concentration, cluster stability, and precipitation driving force is suggested.

  14. Complex evaluation of student‘s physical activity by physical health, physical fitness and body composition parameters

    OpenAIRE

    Šiupšinskas, Laimonas

    2007-01-01

    Physical activity level of students is decreasing. Students are specific population group with similar patterns of habitual physical activity influenced by study process. That formed requirement to search for a new ways to assess physical activity of the students indirectly. Offered method assesses level of physical health, measures physical fitness and evaluates body composition. The aim of the study is to evaluate indirectly measured health-enhanced physical activity of the students by phys...

  15. Effect of Reinforcement Content and Technological Parameters on the Properties of Cu-4 wt.% Ni-TiC Composites

    Science.gov (United States)

    Jha, Pushkar; Gautam, R. K.; Tyagi, Rajnesh

    2017-10-01

    The present study deals with the synthesis and investigation of microstructure, density, and hardness behavior of Cu-4 wt.% Ni-TiC metal matrix composites, produced by high-energy ball milling, followed by compaction and sintering. Matrix of Cu-4 wt.% Ni was used, and different weight percentages (0, 2, 4, 6, and 8) of TiC particles were added. The uniform distribution of TiC particles in the matrix alloy was confirmed by characterizing these composite powders by using scanning electron microscope, energy-dispersive spectroscopy, and x-ray diffraction. Both the density and the hardness of the composite containing 4 wt.% TiC were found to be the highest. The density was found to decrease with increasing TiC content beyond 4 wt.%, and it has been attributed to the agglomeration of TiC particles leading to the formation of pores when added in relatively larger amounts. The compressibility behaviors of the milled powders were studied by using Panelli and Ambrosio Filho equation.

  16. The Investigation of Isotopic Composition of Precipitation and water vapour by Using Air Mass Trajectories and Meteorological Parameters

    International Nuclear Information System (INIS)

    Dirican, A.; Acar, Y.; Demircan, M.

    2002-01-01

    In last century there are so many studies were carried out about stable isotopes of precipitation. The Researchers, study in this field directed to examine origin and transport of water vapour. To investigate the conditions of precipitation formation parallel with climatic changes, stable isotopes using as a powerful tool. So that a project coordinated by IAEA. In this presentation we will give some parts of this project which was carried out in Turkey. First results were obtained for 2001 year. The one of the first result which was obtained in this project is the relation between air temperature and isotopic composition of precipitation collected in Ankara Antalya and Adana station. Second was the observation of temporal variation of stable isotope composition in precipitation and water vapour in relation with water vapour transport. δD and δ 18 O content of atmospheric water vapour examined for January - December 2001 time interval. 27 precipitation event had been examined, starting from endengered place and following to trajectories until to reach Turkey, by using ground level and 500mbar synoptic charts. The observed δD and δ 18 O variations of water vapour is related with the endengered place (Atlantic Ocean, Mediterranean Sea, etc.) of water vapour. The isotopic composition of local precipitation forms by regional meteorological factors. In this study δD and δ 18 O relation of event, daily precipitation and water vapour were defined

  17. Multiscale analysis of the correlation of processing parameters on viscidity of composites fabricated by automated fiber placement

    Science.gov (United States)

    Han, Zhenyu; Sun, Shouzheng; Fu, Yunzhong; Fu, Hongya

    2017-10-01

    Viscidity is an important physical indicator for assessing fluidity of resin that is beneficial to contact resin with the fibers effectively and reduce manufacturing defects during automated fiber placement (AFP) process. However, the effect of processing parameters on viscidity evolution is rarely studied during AFP process. In this paper, viscidities under different scales are analyzed based on multi-scale analysis method. Firstly, viscous dissipation energy (VDE) within meso-unit under different processing parameters is assessed by using finite element method (FEM). According to multi-scale energy transfer model, meso-unit energy is used as the boundary condition for microscopic analysis. Furthermore, molecular structure of micro-system is built by molecular dynamics (MD) method. And viscosity curves are then obtained by integrating stress autocorrelation function (SACF) with time. Finally, the correlation characteristics of processing parameters to viscosity are revealed by using gray relational analysis method (GRAM). A group of processing parameters is found out to achieve the stability of viscosity and better fluidity of resin.

  18. The effect of targeted temperature management on coagulation parameters and bleeding events after out-of-hospital cardiac arrest of presumed cardiac cause

    DEFF Research Database (Denmark)

    Jacob, Marrit; Hassager, Christian; Bro-Jeppesen, John

    2015-01-01

    AIMS: Targeted temperature management (TTM) is part of the standard treatment of comatose patients after out-of-hospital cardiac arrest (OHCA) to attenuate neurological injury. In other clinical settings, hypothermia promotes coagulopathy leading to an increase in bleeding and thrombosis tendency......, thrombelastography (TEG), bleeding, and stent thrombosis events. Platelet counts were lower in the TTM33-group compared to TTM36 (p=0.009), but neither standard coagulation nor TEG-parameters showed any difference between the groups. TEG revealed a normocoagulable state in the majority of patients, while...... approximately 20% of the population presented as hypercoagulable. Adverse events included 38 bleeding events, one stent thrombosis, and one reinfarction, with no significant difference between the groups. CONCLUSIONS: There was no evidence supporting the assumption that TTM at 33°C was associated with impaired...

  19. Optimization the machining parameters by using VIKOR and Entropy Weight method during EDM process of Al–18% SiCp Metal matrix composit

    Directory of Open Access Journals (Sweden)

    Rajesh Kumar Bhuyan

    2016-06-01

    Full Text Available The objective of this paper is to optimize the process parameters by combined approach of VIKOR and Entropy weight measurement method during Electrical discharge machining (EDM process of Al-18wt.%SiCp metal matrix composite (MMC. The central composite design (CCD method is considered to evaluate the effect of three process parameters; namely pulse on time (Ton, peak current (Ip and flushing pressure (Fp on the responses like material removal rate (MRR, tool wear rate (TWR, Radial over cut (ROC and surface roughness (Ra. The Entropy weight measurement method evaluates the individual weights of each response and, using VIKOR method, the multi-objective responses are optimized to get a single numerical index known as VIKOR Index. Then the Analysis of Variance (ANOVA technique is used to determine the significance of the process parameters on the VIKOR Index. Finally, the result of the VIKOR Indexed is validated by conformation test using the liner mathematical model equation develop by responses surface methodology to identify the effectiveness of the proposed method.

  20. The Influence of Pressure Die Casting Parameters on Distribution of Reinforcing Particles in the AlSi11/10% SiC Composite

    Directory of Open Access Journals (Sweden)

    Pasieka A.

    2013-09-01

    Full Text Available The method of pressure die casting of composites with AlSi11 alloy matrix reinforced with 10 vol. % of SiC particles and the analysis of the distribution of particles within the matrix is presented. The composite castings were produced at various values of the piston velocity in the second stage of injection, at diverse intensification pressure values, and various injection gate width values. The distribution of particles over the entire cross-section of the tensile specimen is shown. The index of distribution was determined on the basis of particle count in elementary measuring fields. The regression equation describing the change of the considered index was found as a function of the pressure die casting parameters. The conclusion presents an analysis of the obtained results and their interpretation.

  1. Effect of processing parameters on the formation of Cf/LAS composites/Ag−Cu−Ti/TC4 brazed joint

    International Nuclear Information System (INIS)

    Liu, Duo; Niu, Hongwei; Liu, Jihou; Song, Xiaoguo; Xia, Long; Feng, Jicai

    2016-01-01

    C f /LAS composites were successfully jointed to TC4 alloy with Ag−Cu−Ti filler by vacuum brazing. The interfacial microstructure of TC4/C f /LAS composites joints was characterized by employing scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-diffraction (XRD) and transmission electron microscopy (TEM). The determination of the thin interfacial reaction layer (TiSi 2 + TiC layer) was realized by TEM. The effect of holding time on the interfacial microstructure and shear strength were investigated. With the increasing holding time, the thickness of diffusion layer, Ti 3 Cu 4 layer, and TiSi 2 + TiC layer increased obviously, on the contrary, that of Ti−Cu intermetallic compound layers decreased gradually. Besides, blocky Ti 3 Cu 4 phase was coarsened when the joint was brazed at 890 °C for 20 min, which deteriorated the mechanical properties of the joint dramatically. The interfacial evolution of TC4/C f /LAS composites joint and the formation of TiSi 2 , TiC, Ti 3 Cu 4 , TiCu and Ti 2 Cu phases were expounded. The maximum shear strength of 26.4 MPa was obtained when brazed at 890 °C for 10 min. - Highlights: •The thin interface reaction layer was determined to be TiSi 2 + TiC layer by TEM. •Holding time had influence on the interfacial microstructure and joint properties. •Microstructural evolution mechanism and reactions of brazed joints were expounded.

  2. Effects of herbal supplements on growth performance of sea bass (Dicentrarchus labrax: Change in body composition and some blood parameters

    Directory of Open Access Journals (Sweden)

    SEVDAN YILMAZ

    2012-01-01

    Full Text Available This study was conducted to investigate the effects of dietary thyme (Thymus vulgaris, rosemary (Rosmarinus officinalis and fenugreek (Trigonella foenum graecum as feed additives on growth performance, proximate composition and ammonia excretion of European sea bass Dicentrarchus labrax. Four isonitrogenous (48% crude protein and isocaloric (21 kj/g diets were formulated to contain 0% (control or 1% of thyme, rosemary or fenugreek. The thyme supplementation significantly increased protein efficiency ratio, fillet protein levels, protein and energy retentions (P0.05. The results indicate that dietary thyme improved the protein and energy retentions of sea bass.

  3. MR assessment of red marrow distribution and composition in the proximal femur: correlation with clinical and laboratory parameters

    International Nuclear Information System (INIS)

    Berg, B.C. vande; Lecouvet, F.E.; Moysan, P.; Maldague, B.; Malghem, J.; Jamart, J.

    1997-01-01

    Objective. To correlate the MR appearance of the proximal femur marrow with clinical and blood parameters. Design and patients. The proportion of the femoral neck surface area occupied by red marrow was determined on T1-weighted magnetic resonance (MR) images of the hip in a series of 120 subjects, aged from 15 to 75 years, with ten females and ten males per decade, and correlated with clinical data. This parameter and the bulk T1 values of femoral red marrow were determined in 30 other subjects 25-46 years of age and correlated with their blood parameters. Results. In the series of 120 subjects, the proportion of red marrow surface area decreased with age (P -4 ) and was higher in female than male subjects (P -4 ). Within each decade, the proportion of red marrow surface area was higher in females than in males between 25 and 65 years but neither before 25 nor after 65 years. In the series of 30 subjects, the proportion of red marrow surface area and bulk T1 values of femoral red marrow were significantly negatively correlated with hemoglobin blood levels but not with blood cell counts. Conclusion. The MR appearance of proximal femur red marrow is influenced by age and sex. A relationship with hemoglobin blood level is demonstrated. (orig.)

  4. Volatile fraction composition and physicochemical parameters as tools for the differentiation of lemon blossom honey and orange blossom honey.

    Science.gov (United States)

    Kadar, Melinda; Juan-Borrás, Marisol; Carot, Jose M; Domenech, Eva; Escriche, Isabel

    2011-12-01

    Volatile fraction profile and physicochemical parameters were studied with the aim of evaluating their effectiveness for the differentiation between lemon blossom honey (Citrus limon L.) and orange blossom honey (Citrus spp.). They would be useful complementary tools to the traditional analysis based on the percentage of pollen. A stepwise discriminant analysis constructed using 37 volatile compounds (extracted by purge and trap and analysed by gas chromatography-mass spectrometry), and physicochemical and colour parameters (diastase, conductivity, Pfund colour and CIE L a b) together provided a model that permitted the correct classification of 98.3% of the original and 96.6% of the cross-validated cases, indicating its efficiency and robustness. This model proved its effectiveness in the differentiation of both types of honey with another set of batches from the following year. This model, developed from the volatile compounds, physicochemical and colour parameters, has been useful for the differentiation of lemon and orange blossom honeys. Furthermore, it may be of particular interest for the attainment of a suitable classification of orange honey in which the pollen count is very low. These capabilities imply an evident marketing advantage for the beekeeping sector, since lemon blossom honey could be commercialized as unifloral honey and not as generic citrus honey and orange blossom honey could be correctly characterized. Copyright © 2011 Society of Chemical Industry.

  5. Age- and Sex-Dependent Values of the Distribution of Body Composition Parameters Among Chinese Children Using the Hattori Chart.

    Science.gov (United States)

    Guo, Bin; Hu, Li; Wu, Qiulian; Gong, Jian; Xu, Hao

    This study aimed to examine the relationship between the fat-free mass (FFM) and fat mass (FM) and between the fat-free mass index (FFMI) and fat mass index (FMI) in Chinese children using the Hattori chart and to compare the changing pattern with Korean counterparts. In this study, 1541 (764 girls) children and adolescents aged 5-19 yr were recruited from southern China. The subjects' body composition was measured using dual-energy X-ray absorptiometry. The relationship between FFM and FM and between FFMI and FMI were delineated using the Hattori chart. Between 5 and 12 yr, a concurrent increase in FFM and FM and in FFMI and FMI was found in both sexes. After 12 yr, the age-related changing patterns are generally characterized by a sharp increase in FM, with a relatively small increase in FFM for girls, and a sharp increase in FFM, with a relatively little fluctuation in FM for boys. The increase in weight and BMI with age for this stage is largely due to the increase in FFM and FFMI in boys and in both the FFM and FM and FFMI and FMI components in girls. Sex differences in the patterns of body composition were found in Chinese children and adolescents. Copyright © 2016 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

  6. Taguchi design optimization of machining parameters on the CNC end milling process of halloysite nanotube with aluminium reinforced epoxy matrix (HNT/Al/Ep hybrid composite

    Directory of Open Access Journals (Sweden)

    J.S. Pang

    2014-08-01

    Full Text Available This paper introduces the application of Taguchi optimization methodology in optimizing the cutting parameters of end-milling process for machining the halloysite nanotubes (HNTs with aluminium reinforced epoxy hybrid composite material under dry condition. The machining parameters which are chosen to be evaluated in this study are the depth of cut (d, cutting speed (S and feed rate (f. While, the response factors to be measured are the surface roughness of the machined composite surface and the cutting force. An orthogonal array of the Taguchi method was set-up and used to analyse the effect of the milling parameters on the surface roughness and cutting force. The result from this study shows that the application of the Taguchi method can determine the best combination of machining parameters that can provide the optimal machining response conditions which are the lowest surface roughness and lowest cutting force value. For the best surface finish, A1–B3–C3 (d = 0.4 mm, S = 1500 rpm, f = 60 mmpm is found to be the optimized combination of levels for all the three control factors from the analysis. Meanwhile, the optimized combination of levels for all the three control factors from the analysis which provides the lowest cutting force was found to be A2–B2–C2 (d = 0.6 mm, S = 1000 rpm, f = 40 mmpm.

  7. Determination of the Effect of the Elimination Diet Applied for Overweight and Obese People with Food Intolerance on Body Composition and Biochemical Parameters

    Directory of Open Access Journals (Sweden)

    Sema Gubur

    2017-08-01

    Full Text Available ABSTRACT Food Intolerance, is a reaction against food, but not immunological manner, and may be confused with real food allergies. In this study, effects of special weight-loss diet together with an elimination diet on body composition and biochemical parameters of overweight and obese people who were diagnosed with food intolerance were investigated. The study group consists of 20 patients in total who were followed-up and treated in Yorktest Turkey Laboratory; who were diagnosed with food intolerance, and whose BMI was > 26kg/m2. Bloodletting for these patients was executed with Lancet from their fingertips, and the blood drawn from these patients was assessed via enzyme-linked immunosorbent assay (ELİSA method, and food reactions of patients were determined for each food. Biochemical parameters of these patients are routine tests, which are necessary for food intolerance tests, and they are analyzed at Yorktest Turkey Laboratory for two times: before and after elimination diet plus special weight-loss diet. It has been determined that, the most common sensivity is obtained against yeast, egg yolk and white, cranberry, cow’s milk, chicken, lentils and parsley. Anthropometric measurements and biochemical parameters before and after elimination diet plus special weight-loss diet applied to participants, were significantly improved in statistical manner. Due to positive changes in body composition and biochemical parameters obtained through application of special weight-loss diets together with elimination diet applied to fat and obese people, we think that this diet might be used for medical nutrition treatment of obesity as a treatment option.

  8. Effects of dietary grape seed proanthocyanidins on growth performance, some serum biochemical parameters and body composition of tilapia (Oreochromis niloticus fingerlings

    Directory of Open Access Journals (Sweden)

    Shao Wei Zhai

    2014-07-01

    Full Text Available The present study was performed with tilapia (Oreochromis niloticus to evaluate the effects of diet supplementation with grape seed proanthocyanidins (GSPs on fish growth performance, some serum parameters and body composition. Three hundred tilapia fingerlings with the initial average body weight of 9.50±1.25 g were randomly divided into five treatment groups with four replicates in each group and 15 fish in each replicate. The dietary GSPs levels of five treatment groups were 0 (control group, 200, 400, 600, and 800 mg/kg, respectively. The trial period was 49 days. Growth performance parameters were significantly improved by GSPs supplementation (P<0.05, while survival rates were similar among all groups (P>0.05. Serum parameter results showed that activities of aminotransferase aspartate in 200 and 400 mg/kg GSPs groups and alanine aminotransferase in 400 mg/kg GSPs group were lowered significantly (P<0.05. Levels of triglyceride and total cholesterol (except 200 mg/kg GSPs group were significantly lowered, while lysozyme activity and albumin level were significantly higher in fish of GSPs supplemented groups, independently from the level of supplementation. The highest crude protein level and lowest crude lipid level were found in fish of all GSPs supplemented groups, while levels of moisture and ash in fish of all groups were similar (P>0.05. The results indicated that dietary 200 mg/kg GSPs could exert beneficial effects on growth and body composition of tilapia fingerlings, and ameliorate serum biochemistry parameters related to health status.

  9. Evaluation of circuit models for an IPMC (ionic polymer-metal composite) sensor using a parameter estimate method

    International Nuclear Information System (INIS)

    Park, Kiwon; Lee, Hyungki

    2012-01-01

    The present study investigated a sensor system to effectively detect the bending angles applied on an ionic polymer metal composite sensor. Firstly, the amount of net charge produced by the motion of cations was correlated to the bending angle based on the geometric relationship between a flat and a bent IPMC, and the relationship was represented by linear and nonlinear polynomial equations. Secondly, several existing and modified R and C circuit models with a linear charge model were evaluated using the experimental data. Thirdly, the nonlinear charge model was applied to a selected circuit model, and the effectivenesses of the linear and the nonlinear charge models were compared. Finally, the sensor output signal was fed into the inverse model of the identified circuit model to reproduce the bending angles. This paper presents a simple data processing procedure using the inverse transfer function of a selected circuit model that successfully monitored various bending motions of an IPMC sensor.

  10. Comparative Study on Dispersion and Interfacial Properties of Single Walled Carbon Nanotube/Polymer Composites Using Hansen Solubility Parameters

    DEFF Research Database (Denmark)

    Ma, Jing; Larsen, Mikael

    2013-01-01

    fabricated by solution blending 1 wt % SWNTs with various modification (nonmodified, nitric acid functionalized, and amine functionalized SWNTs) and three kinds of polymeric materials (polycarbonate, polyvinylidene fluoride, and epoxy). Chemical compatibilities between SWNTs and solvents or polymers...... are calculated by the Hansen solubility parameters (HSP) method. The dispersion of the SWNTs in solvents is evaluated by dynamic light scattering. The dispersion of SWNTs in polymers evaluated by a light optical microscope (LOM) generally agrees with the HSP prediction. The strain transfer from the matrix...

  11. Fluidized bed pyrolysis of HDPE: A study of the influence of operating variables and the main fluid dynamic parameters on the composition and production of gases

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Lidia; Aguado, Alicia; Moral, Alberto [CARTOF Centro Tecnologico, Valladolid (Spain). Environmental Div.; Irusta, Ruben [CARTOF Centro Tecnologico, Valladolid (Spain). Environmental Div.; Valladolid Univ. (Spain). Dept. of Chemical Engineering and Environmental Technology

    2011-02-15

    In the present work, a preliminary study of the pyrolysis process of high density polyethylene (HDPE) in a fluidized bed is investigated in order to determine the influence between the fluid dynamic properties of the bed reactor and the amount and composition of the gases produced. As is known, fluidized bed technology is a very interesting option to apply in the pyrolysis field due to i) the lack of moving parts in the hot region that facilitates the maintenance of equipment, ii) the high surface area to volume ratio available in the bed, and iii) the high heat transfer coefficient reached which governs the reaction products. But, heat and mass transfer coefficients are strongly affected by the fluid dynamic properties of the bed. During the pyrolysis of HDPE, a fluid dynamic characterization of the bed particles that consist of char-coated sand of HDPE has been carried out. Parameters such as the minimum fluidizing velocity (u{sub mf}), terminal velocity (u{sub t}), bed height (h{sub f}), bed voidage ({epsilon}{sub f}), fraction of the bed occupied by bubbles ({delta}), bubble diameter (d{sub b}), bubble velocity (u{sub b}), the mass transfer coefficients between the bubble and the cloud (K{sub bc}) and between the cloud and the emulsion (K{sub ce}) were determined. Subsequently, the influence of major operating variables and the fluid dynamic parameters on the composition and the gas yield of the pyrolysis of HDPE were studied. (author)

  12. Effect of marine by-product meals on hen egg production parameters, yolk lipid composition and sensory quality.

    Science.gov (United States)

    Toyes-Vargas, E; Ortega-Pérez, R; Espinoza-Villavicencio, J L; Arellano-Pérez, M; Civera, R; Palacios, E

    2018-04-01

    The effect of including 5% marine by-product meals in feeds of laying hens on egg production, composition and sensory characteristics was tested. Marine by-product meals were prepared using two methods: (i) cooking (100°C/10 min) followed by drying (60°C/24 hr) or (ii) grinding followed by drying. The raw materials used for meal production were scallop or squid viscera, shrimp heads or whole mackerel. A total of 108 laying hens were allocated to nine diet treatments; one control diet (corn and soya bean based) and eight experimental diets, containing 95% of the control feed and 5% of the experimental meal for three weeks. Daily intake was higher in hens fed the dried mackerel and cooked shrimp meals. All the experimental treatments showed significantly higher concentration of n-3 HUFA in yolk reserves and phospholipids compared to the control (0.12-0.13 g per 100 g), especially those with scallop or squid prepared by both methods (0.53-0.95 g per 100 g). Scallop, squid and shrimp meal inclusion in the feed produced eggs with more astaxanthin (0.22 mg per 100 g) while this carotenoid was absent in the control and mackerel treatments. Visual evaluation of raw yolk colour increased with the inclusion of marine by-product meals with higher values in hens fed shrimp heads (13), followed by scallop viscera (11), squid viscera (9), and with similar values for mackerel and control (4). The taste, aroma, texture and colour of cooked eggs from different treatments were not statically different when evaluated by a panel of 60 untrained people. These results suggest that meals from marine by-products are a better alternative for improving egg yolk composition by increasing n-3 HUFA when compared to fishmeal as they also increase astaxanthin and yolk pigmentation without affecting egg sensory characteristics. © 2017 Blackwell Verlag GmbH.

  13. Adjusting shape-memory properties of amorphous polyether urethanes and radio-opaque composites thereof by variation of physical parameters during programming

    International Nuclear Information System (INIS)

    Cui, J; Kratz, K; Lendlein, A

    2010-01-01

    Various composites have been prepared to improve the mechanical properties of shape-memory polymers (SMPs) or to incorporate new functionalities (e.g. magneto-sensitivity) in polymer matrices. In this paper, we systematically investigated the influence of the programming temperature T prog and the applied strain ε m as parameters of the shape-memory creation procedure (SMCP) on the shape-memory properties of an amorphous polyether urethane and radio-opaque composites thereof. Recovery under stress-free conditions was quantified by the shape recovery rate R r and the switching temperature T sw , while the maximum recovery stress σ max was determined at the characteristic temperature T σ,max under constant strain conditions. Excellent shape-memory properties were achieved in all experiments with R r values in between 80 and 98%. σ max could be tailored from 0.4 to 3.7 MPa. T sw and T σ,max could be systematically adjusted from 33 to 71 °C by variation of T prog for each investigated sample. The investigated radio-opaque shape-memory composites will form the material basis for mechanically active scaffolds, which could serve as an intelligent substitute for the extracellular matrix to study the influence of mechanical stimulation of tissue development

  14. Adaptation of model proteins from cold to hot environments involves continuous and small adjustments of average parameters related to amino acid composition.

    Science.gov (United States)

    De Vendittis, Emmanuele; Castellano, Immacolata; Cotugno, Roberta; Ruocco, Maria Rosaria; Raimo, Gennaro; Masullo, Mariorosario

    2008-01-07

    The growth temperature adaptation of six model proteins has been studied in 42 microorganisms belonging to eubacterial and archaeal kingdoms, covering optimum growth temperatures from 7 to 103 degrees C. The selected proteins include three elongation factors involved in translation, the enzymes glyceraldehyde-3-phosphate dehydrogenase and superoxide dismutase, the cell division protein FtsZ. The common strategy of protein adaptation from cold to hot environments implies the occurrence of small changes in the amino acid composition, without altering the overall structure of the macromolecule. These continuous adjustments were investigated through parameters related to the amino acid composition of each protein. The average value per residue of mass, volume and accessible surface area allowed an evaluation of the usage of bulky residues, whereas the average hydrophobicity reflected that of hydrophobic residues. The specific proportion of bulky and hydrophobic residues in each protein almost linearly increased with the temperature of the host microorganism. This finding agrees with the structural and functional properties exhibited by proteins in differently adapted sources, thus explaining the great compactness or the high flexibility exhibited by (hyper)thermophilic or psychrophilic proteins, respectively. Indeed, heat-adapted proteins incline toward the usage of heavier-size and more hydrophobic residues with respect to mesophiles, whereas the cold-adapted macromolecules show the opposite behavior with a certain preference for smaller-size and less hydrophobic residues. An investigation on the different increase of bulky residues along with the growth temperature observed in the six model proteins suggests the relevance of the possible different role and/or structure organization played by protein domains. The significance of the linear correlations between growth temperature and parameters related to the amino acid composition improved when the analysis was

  15. Environmental and traffic-related parameters affecting road dust composition: A multi-technique approach applied to Venice area (Italy)

    Science.gov (United States)

    Valotto, Gabrio; Rampazzo, Giancarlo; Visin, Flavia; Gonella, Francesco; Cattaruzza, Elti; Glisenti, Antonella; Formenton, Gianni; Tieppo, Paulo

    2015-12-01

    Road dust is a non-exhaust source of atmospheric particulate by re-suspension. It is composed of particles originating from natural sources as well as other non-exhaust source such as tire, brake and asphalt wear. The discrimination between atmospheric particles directly emitted from abrasion process and those related to re-suspension is therefore an open issue, as far as the percentage contribution of non-exhaust emissions is becoming more considerable due also to the recent policy actions and the technological upgrades in the automotive field, focused on the reduction of exhaust emissions. In this paper, road dust collected along the bridge that connects Venice (Italy) to the mainland is characterized with a multi-technique approach in order to determine its composition depending on environmental as well as traffic-related conditions. Six pollutant sources of road dust particles were identified by cluster analysis: brake, railway, tire, asphalt, soil + marine, and mixed combustions. Considering the lack of information on this matrix in this area, this study is intended to provide useful information for future identification of road dust re-suspension source in atmospheric particulate.

  16. Effect of Forging Parameters on Low Cycle Fatigue Behaviour of Al/Basalt Short Fiber Metal Matrix Composites

    Directory of Open Access Journals (Sweden)

    R. Karthigeyan

    2013-01-01

    Full Text Available This paper deals with metal matrix composites (MMCs of Al 7075 alloy containing different weight percentage (2.5, 5, 7.5, and 10 basalt short fiber reinforcement and unreinforced matrix alloy. The samples were produced by the permanent stir casting technique. The casting ingots were cut into blanks to be forged in single stage and double stage, using MN press and graphite-based lubricant. The microstructures and fatigue properties of the matrix alloy and MMC samples were investigated in the as cast state and in the single and double stage forging operations. The microstructure results showed that the forged sample had a uniform distribution of the basalt short fiber throughout the specimens. Evaluation of the fatigue properties showed that the forged samples had higher values than those of the as cast counterparts. After forging, the enhancement of the fatigue strength of the matrix alloy was so significant and high in the case of 2.5 and 5.0 wt. percentage basalt short fiber reinforced MMC, and there was no enhancement in 7.5 and 10 weight percentages short fiber reinforced MMCs. The fracture damage was mainly due to decohesion at the matrix-fiber interface.

  17. Effect of forging parameters on low cycle fatigue behaviour of Al/basalt short fiber metal matrix composites.

    Science.gov (United States)

    Karthigeyan, R; Ranganath, G

    2013-01-01

    This paper deals with metal matrix composites (MMCs) of Al 7075 alloy containing different weight percentage (2.5, 5, 7.5, and 10) basalt short fiber reinforcement and unreinforced matrix alloy. The samples were produced by the permanent stir casting technique. The casting ingots were cut into blanks to be forged in single stage and double stage, using MN press and graphite-based lubricant. The microstructures and fatigue properties of the matrix alloy and MMC samples were investigated in the as cast state and in the single and double stage forging operations. The microstructure results showed that the forged sample had a uniform distribution of the basalt short fiber throughout the specimens. Evaluation of the fatigue properties showed that the forged samples had higher values than those of the as cast counterparts. After forging, the enhancement of the fatigue strength of the matrix alloy was so significant and high in the case of 2.5 and 5.0 wt. percentage basalt short fiber reinforced MMC, and there was no enhancement in 7.5 and 10 weight percentages short fiber reinforced MMCs. The fracture damage was mainly due to decohesion at the matrix-fiber interface.

  18. Tamoxifen affects glucose and lipid metabolism parameters, causes browning of subcutaneous adipose tissue and transient body composition changes in C57BL/6NTac mice

    International Nuclear Information System (INIS)

    Hesselbarth, Nico; Pettinelli, Chiara; Gericke, Martin; Berger, Claudia; Kunath, Anne; Stumvoll, Michael; Blüher, Matthias; Klöting, Nora

    2015-01-01

    Tamoxifen is a selective estrogen receptor (ER) modulator which is widely used to generate inducible conditional transgenic mouse models. Activation of ER signaling plays an important role in the regulation of adipose tissue (AT) metabolism. We therefore tested the hypothesis that tamoxifen administration causes changes in AT biology in vivo. 12 weeks old male C57BL/6NTac mice were treated with either tamoxifen (n = 18) or vehicle (n = 18) for 5 consecutive days. Tamoxifen treatment effects on body composition, energy homeostasis, parameters of AT biology, glucose and lipid metabolism were investigated up to an age of 18 weeks. We found that tamoxifen treatment causes: I) significantly increased HbA 1c , triglyceride and free fatty acid serum concentrations (p < 0.01), II) browning of subcutaneous AT and increased UCP-1 expression, III) increased AT proliferation marker Ki67 mRNA expression, IV) changes in adipocyte size distribution, and V) transient body composition changes. Tamoxifen may induce changes in body composition, whole body glucose and lipid metabolism and has significant effects on AT biology, which need to be considered when using Tamoxifen as a tool to induce conditional transgenic mouse models. Our data further suggest that tamoxifen-treated wildtype mice should be characterized in parallel to experimental transgenic models to control for tamoxifen administration effects. - Highlights: • Tamoxifen treatment causes significantly increased HbA 1c , triglyceride and free fatty acid serum concentrations. • Tamoxifen induces browning of subcutaneous AT and increased UCP-1 expression. • Tamoxifen changes adipocyte size distribution, and transient body composition

  19. Tamoxifen affects glucose and lipid metabolism parameters, causes browning of subcutaneous adipose tissue and transient body composition changes in C57BL/6NTac mice

    Energy Technology Data Exchange (ETDEWEB)

    Hesselbarth, Nico; Pettinelli, Chiara [Department of Medicine, University of Leipzig, D-04103 Leipzig (Germany); Gericke, Martin [Institute of Anatomy, University of Leipzig, D-04103 Leipzig (Germany); Berger, Claudia [IFB Adiposity Disease, Core Unit Animal Models, University of Leipzig, D-04103 Leipzig (Germany); Kunath, Anne [German Center for Diabetes Research (DZD), Leipzig (Germany); Stumvoll, Michael; Blüher, Matthias [Department of Medicine, University of Leipzig, D-04103 Leipzig (Germany); Klöting, Nora, E-mail: nora.kloeting@medizin.uni-leipzig.de [IFB Adiposity Disease, Core Unit Animal Models, University of Leipzig, D-04103 Leipzig (Germany)

    2015-08-28

    Tamoxifen is a selective estrogen receptor (ER) modulator which is widely used to generate inducible conditional transgenic mouse models. Activation of ER signaling plays an important role in the regulation of adipose tissue (AT) metabolism. We therefore tested the hypothesis that tamoxifen administration causes changes in AT biology in vivo. 12 weeks old male C57BL/6NTac mice were treated with either tamoxifen (n = 18) or vehicle (n = 18) for 5 consecutive days. Tamoxifen treatment effects on body composition, energy homeostasis, parameters of AT biology, glucose and lipid metabolism were investigated up to an age of 18 weeks. We found that tamoxifen treatment causes: I) significantly increased HbA{sub 1c}, triglyceride and free fatty acid serum concentrations (p < 0.01), II) browning of subcutaneous AT and increased UCP-1 expression, III) increased AT proliferation marker Ki67 mRNA expression, IV) changes in adipocyte size distribution, and V) transient body composition changes. Tamoxifen may induce changes in body composition, whole body glucose and lipid metabolism and has significant effects on AT biology, which need to be considered when using Tamoxifen as a tool to induce conditional transgenic mouse models. Our data further suggest that tamoxifen-treated wildtype mice should be characterized in parallel to experimental transgenic models to control for tamoxifen administration effects. - Highlights: • Tamoxifen treatment causes significantly increased HbA{sub 1c}, triglyceride and free fatty acid serum concentrations. • Tamoxifen induces browning of subcutaneous AT and increased UCP-1 expression. • Tamoxifen changes adipocyte size distribution, and transient body composition.

  20. The effect of intake of water on the final values of body composition parameters in active athletes using two different bioimpedance analyzers

    Directory of Open Access Journals (Sweden)

    Petr Kutáč

    2014-06-01

    Full Text Available Background:The method of bioelectrical impedance (BIA is frequently used to estimate body composition in sports. The total body water (TBW is the basic variable that BIA measures. That implies the degree of sensitivity of BIA to the hydration of the organism, which is also demonstrated by the principles of measurement that primarily relate to the hydration of the organism. It is difficult to provide standard hydration of the organism of subjects prior to measurements when taking the measurements in the field. Objective:The objective of the study is to assess the changes in the final values of the selected body composition parameters in soccer players caused by intake of water, using two devices commonly used in the field. Methods:The research was performed in a group of 33 soccer players (mean age 20.30 ± 1.18 years. The measurements were taken using Tanita BC 418 MA (frequency 50 kHz and Nutriguard-M (frequency 100 kHz. To evaluate the effect of water intake, we took two measurements before and after the intake of 500 ml of water. The parameters measured by Tanita BC 418 MA were body weight (BW, total body water (TBW, body fat (BF, fat free mass (FFM. Nutriguard-M was used to measure total body water (TBW, intra and extracellular water (ICW and ECW, body fat (BF, fat free mass (FFM, intra and extracellular mass (BCM and ECM. The differences in the means (M1 and M2 of the monitored parameters were evaluated using the Paired Samples t-test. In statistically significant differences in the mean, the practical significance was also verified using the effect of size (Cohen's d. Results:The Tanita device showed statistically significant differences after the intake of 500 ml in parameters BW (+0.42 kg, BF (+0.39 kg, +0.53% and TBW (-0.38%. As for the Nutriguard device, statistically significant differences were found in parameters TBW (+0.77 kg, ICW (+0.83 kg, FFM (+1.05 kg, BCM (+0.79 kg and ECM/BCM (-0.01. Conclusion

  1. Effects of particle composition and environmental parameters on catalytic hydrodechlorination of trichloroethylene by nanoscale bimetallic Ni-Fe.

    Science.gov (United States)

    Wei, Jianjun; Qian, Yajing; Liu, Wenjuan; Wang, Lutao; Ge, Yijie; Zhang, Jianghao; Yu, Jiang; Ma, Xingmao

    2014-05-01

    Catalytic nickel was successfully incorporated into nanoscale iron to enhance its dechlorination efficiency for trichloroethylene (TCE), one of the most commonly detected chlorinated organic compounds in groundwater. Ethane was the predominant product. The greatest dechlorination efficiency was achieved at 22 molar percent of nickel. This nanoscale Ni-Fe is poorly ordered and inhomogeneous; iron dissolution occurred whereas nickel was relatively stable during the 24-hr reaction. The morphological characterization provided significant new insights on the mechanism of catalytic hydrodechlorination by bimetallic nanoparticles. TCE degradation and ethane production rates were greatly affected by environmental parameters such as solution pH, temperature and common groundwater ions. Both rate constants decreased and then increased over the pH range of 6.5 to 8.0, with the minimum value occurring at pH 7.5. TCE degradation rate constant showed an increasing trend over the temperature range of 10 to 25°C. However, ethane production rate constant increased and then decreased over the range, with the maximum value occurring at 20°C. Most salts in the solution appeared to enhance the reaction in the first half hour but overall they displayed an inhibitory effect. Combined ions showed a similar effect as individual salts. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  2. In vivo assessment of an industrial waste product as a feed additive in dairy cows: Effects of larch (Larix decidua L.) sawdust on blood parameters and milk composition.

    Science.gov (United States)

    Tedesco, D; Garavaglia, L; Spagnuolo, M S; Pferschy-Wenzig, E M; Bauer, R; Franz, C

    2015-12-01

    When larch (Larix spp.) is processed in the wood industry, the sawdust is currently disposed of as waste or used as combustible material, even though it is rich in biologically active compounds. In this study the effect of larch sawdust supplementation on blood parameters as well as milk composition was examined in healthy mid-lactating dairy cows. Twenty-four multiparous Italian Friesian dairy cows were assigned to groups receiving either 300 g/day/cow of larch sawdust or a control diet, and treatments were continued for a 20 day period. Milk parameters were unaffected by treatment. A lower plasma total protein concentration was observed and can be attributed to a decrease in globulin concentration. A lower plasma urea concentration was also detected in the larch group. Moreover, biomarkers of liver function were influenced by the treatment. Total bilirubin was lower in larch-treated animals, and cholesterol tended to be lower. In addition, an interaction between day and treatment was observed for very low density lipoprotein. The concentration of other parameters, including reactive oxygen metabolites, superoxide dismutase, glutathione peroxidase and nitrotyrosine, did not differ between treatments. The observed benefits, together with the good palatability, make larch sawdust a promising candidate for the development of beneficial feed supplements for livestock. Further studies will be useful, particularly to evaluate its efficacy in different health conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Optimizing the parameters of heat transmission in a small heat exchanger with spiral tapes cut as triangles and Aluminum oxide nanofluid using central composite design method

    Science.gov (United States)

    Ghasemi, Nahid; Aghayari, Reza; Maddah, Heydar

    2018-02-01

    The present study aims at optimizing the heat transmission parameters such as Nusselt number and friction factor in a small double pipe heat exchanger equipped with rotating spiral tapes cut as triangles and filled with aluminum oxide nanofluid. The effects of Reynolds number, twist ratio (y/w), rotating twisted tape and concentration (w%) on the Nusselt number and friction factor are also investigated. The central composite design and the response surface methodology are used for evaluating the responses necessary for optimization. According to the optimal curves, the most optimized value obtained for Nusselt number and friction factor was 146.6675 and 0.06020, respectively. Finally, an appropriate correlation is also provided to achieve the optimal model of the minimum cost. Optimization results showed that the cost has decreased in the best case.

  4. Effect of Synthesis Parameters on the Structure and Magnetic Properties of Magnetic Manganese Ferrite/Silver Composite Nanoparticles Synthesized by Wet Chemistry Method

    DEFF Research Database (Denmark)

    Huy, L.T.; Tam, L.T.; Phan, V.N.

    2016-01-01

    In the present work, magnetic manganese ferrite/silver (MnFe2O4-Ag) composite nanoparticles were synthesized by wet chemistry method. This synthesis process consists of two steps: first, the seed of manganese ferrite nanoparticles (MnFe2O4 NPs) was prepared by a coprecipitationmethod; second......, growth of silver nanoparticles (AgNPs) on the MnFe2O4 seed by modified photochemical reaction. We have conducted systematically the effects of synthesis parameters such as pH value, synthesis time, precursor salts concentration, mass ratio and stabilizing agents on the structure and magnetic properties......-prepared MnFe2O4-Ag magnetic nanocomposites display excellent properties of high crystallinity, long-term aggregation stability in aqueous medium, large saturation magnetization in the range of 15-20 emu/g, and small sizes of Ag-NPs similar to 20 nm. These exhibited properties made the MnFe2O4-Ag...

  5. Effects of chromium-enriched bacillus subtilis KT260179 supplementation on chicken growth performance, plasma lipid parameters, tissue chromium levels, cecal bacterial composition and breast meat quality.

    Science.gov (United States)

    Yang, Jiajun; Qian, Kun; Zhang, Wei; Xu, Yayuan; Wu, Yijing

    2016-11-08

    Both chromium (Cr) and probiotic bacillus own the virtues of regulating animal metabolism and meat quality. Purpose of this study was to evaluate the efficiency of supplemental Cr and bacillus in the form of chromium-enriched Bacillus subtilis KT260179 (CEBS) on chicken growth performance, plasma lipid parameters, tissue chromium levels, cecal bacterial composition and breast meat quality. Six hundred of 1-day-old Chinese Huainan Partridge chickens were divided into four groups randomly: Control, inorganic Cr, Bacillus subtilis, and CEBS. The feed duration was 56 days. After 28 days of treatment, broiler feed CEBS or normal B. subtilis had higher body weights than control broiler, and after 56 days, chickens given either CEBS or B. subtilis had greater body weights than control broiler or those given inorganic Cr. Plasma total cholesterol, triglycerides, and low density lipoprotein cholesterol levels declined significantly in the CEBS group compared with the control, whereas plasma high density lipoprotein cholesterol levels increased significantly. The concentration of Cr in blood and breast muscle increased after CEBS and inorganic Cr supplementation. B. subtilis and CEBS supplementation caused a significant increase in the numbers of Lactobacillus and Bifidobacterium in the caecum, while the numbers of Escherichia coli and Salmonella decreased significantly compared to the control. Feed adding CEBS increased the lightness, redness, and yellowness of breast meat, improved the water-holding capacity, decreased the shear force and cooking loss. In all, CEBS supplementation promoted body growth, improved plasma lipid parameters, increased tissue Cr concentrations, altered cecal bacterial composition and improved breast meat quality.

  6. [Assessment of the nutritional status of a group of people older than 50 years by means of dietary and body composition parameters].

    Science.gov (United States)

    Martínez Roldán, C; Veiga Herreros, P; Cobo Sanz, J Ma; Carbajal Azcona, A

    2011-01-01

    To assess the nutritional status of elder adults by means of dietary and body composition parameters. The sample comprised 49 adults, older than 50 years (23 men and 26 women) with a mean age of 54.84±4.56 years, working at a private university. The body composition was analyzed by using anthropometric parameters. The energy and nutrients intake was gathered by means of a registry of all the foods and beverages consumed during 3 days that was filled-up by each (previously instructed) participant and estimating the amounts through photographic models. Total energy requirements were estimated by the Harris-Benedict and FAO/WHO calculations. The body mass index was similar (p=0.018) in both men and women (26.1±1.9 and 24.4±2.8 kg/m²). The percentage of fat obtained by anthropometrics was 29.6±3.6 and 36.8±3.1% (p=0.000) in men and women, respectively. The level of physical activity was very light to light. Daily energy intake was appropriate for total energy demands when these were calculated by the calculations proposed by FAO/WHO. The caloric profile indicated an unbalance with high proteins and lipids and low carbohydrates intake. As for the micronutrients, the diets assessed indicated a deficient intake of folic acid and vitamins D and E, in both genders, and zinc and selenium also in women. We have found overweight problems according to the BMI and the waist circumference, and obesity according to the body fat percentage, with the potential risk for the development of an associated complication. It would be advisable to improve the quality of the diets consumed by increasing the amount of some micronutrients and fiber, and by promoting an increase in the physical activity.

  7. The influence of growth parameters on the structure and composition of CuGaS{sub 2} epilayers grown by MOVPE

    Energy Technology Data Exchange (ETDEWEB)

    Branch, M.S. [Physics Department, Nelson Mandela Metropolitan University, Port Elizabeth 6031 (South Africa)]. E-mail: Matthew.Branch@nmmu.ac.za; Berndt, P.R. [Physics Department, Nelson Mandela Metropolitan University, Port Elizabeth 6031 (South Africa); Leitch, A.W.R. [Physics Department, Nelson Mandela Metropolitan University, Port Elizabeth 6031 (South Africa); Botha, J.R. [Physics Department, Nelson Mandela Metropolitan University, Port Elizabeth 6031 (South Africa); Weber, J. [Institute for Low Temperature Physics, University of Technology, D-01062 Dresden (Germany)

    2006-04-01

    The influence of various growth parameters on the composition and structure of MOVPE-grown CuGaS{sub 2} is presented. The Cu content of the grown layers is shown to decrease in the direction of the carrier gas flow, whilst the Ga and S content are shown to increase. Changing the flow of Cu(hfac){sub 2}.Et{sub 3}N to vary the I/III ratio in the vapour phase has a greater effect on the composition of grown epilayers than changing the flow of TEGa. This is indicative of Cu being the minority species present at the growth interface. A larger rate of decrease in the Cu content with an increase in both TEGa and DtBS flows suggests pre-reactions between Cu(hfac){sub 2}.Et{sub 3}N and both TEGa and DtBS precursors. Lower substrate temperatures are suggested to be thermodynamically unfavourable for the growth of CuGaS{sub 2}, yet enhance the formation of Ga{sub x}S{sub y} phases. The surface morphology of Cu-rich layers are typically inferior with a high density of crystallites, whilst Cu-poor epilayers are characteristically smooth with a single XRD reflection attributed to the (004) plane of c-axis-orientated epitaxial material.

  8. Effect of Printing Parameters on Tensile, Dynamic Mechanical, and Thermoelectric Properties of FDM 3D Printed CABS/ZnO Composites

    Directory of Open Access Journals (Sweden)

    Yah Yun Aw

    2018-03-01

    Full Text Available Fused deposition modelling (FDM has been widely used in medical appliances, automobile, aircraft and aerospace, household appliances, toys, and many other fields. The ease of processing, low cost and high flexibility of FDM technique are strong advantages compared to other techniques for thermoelectric polymer composite fabrication. This research work focuses on the effect of two crucial printing parameters (infill density and printing pattern on the tensile, dynamic mechanical, and thermoelectric properties of conductive acrylonitrile butadiene styrene/zinc oxide (CABS/ZnO composites fabricated by FDM technique. Results revealed significant improvement in tensile strength and Young’s modulus, with a decrease in elongation at break with infill density. Improvement in dynamic storage modulus was observed when infill density changed from 50% to 100%. However, the loss modulus and damping factor reduced gradually. The increase of thermal conductivity was relatively smaller compared to the improvement of electrical conductivity and Seebeck coefficient, therefore, the calculated figure of merit (ZT value increased with infill density. Line pattern performed better than rectilinear, especially in tensile properties and electrical conductivity. From the results obtained, FDM-fabricated CABS/ZnO showed much potential as a promising candidate for thermoelectric application.

  9. Effect of Printing Parameters on Tensile, Dynamic Mechanical, and Thermoelectric Properties of FDM 3D Printed CABS/ZnO Composites.

    Science.gov (United States)

    Aw, Yah Yun; Yeoh, Cheow Keat; Idris, Muhammad Asri; Teh, Pei Leng; Hamzah, Khairul Amali; Sazali, Shulizawati Aqzna

    2018-03-22

    Fused deposition modelling (FDM) has been widely used in medical appliances, automobile, aircraft and aerospace, household appliances, toys, and many other fields. The ease of processing, low cost and high flexibility of FDM technique are strong advantages compared to other techniques for thermoelectric polymer composite fabrication. This research work focuses on the effect of two crucial printing parameters (infill density and printing pattern) on the tensile, dynamic mechanical, and thermoelectric properties of conductive acrylonitrile butadiene styrene/zinc oxide (CABS/ZnO composites fabricated by FDM technique. Results revealed significant improvement in tensile strength and Young's modulus, with a decrease in elongation at break with infill density. Improvement in dynamic storage modulus was observed when infill density changed from 50% to 100%. However, the loss modulus and damping factor reduced gradually. The increase of thermal conductivity was relatively smaller compared to the improvement of electrical conductivity and Seebeck coefficient, therefore, the calculated figure of merit (ZT) value increased with infill density. Line pattern performed better than rectilinear, especially in tensile properties and electrical conductivity. From the results obtained, FDM-fabricated CABS/ZnO showed much potential as a promising candidate for thermoelectric application .

  10. Objectively measured physical activity levels and sedentary time in 7–9-year-old Estonian schoolchildren: independent associations with body composition parameters

    Directory of Open Access Journals (Sweden)

    Eva-Maria Riso

    2016-04-01

    Full Text Available Abstract Background Sufficient daily physical activity (PA is necessary for physical, social and mental health benefits during growth. Most of the available data on children is based on subjective reports, while only limited data on objective PA and sedentary levels is available for primary school children. Increased PA is also an important health indicator of body composition parameters, especially body adiposity indices. The aim of the present study was to determine objectively the amount of daily PA levels at different intensities and sedentary time in normal-weight (NW and overweight (OW 7–9-year-old boys and girls, and to find associations between objectively measured PA levels and sedentary time with different body composition values. Methods Two hundred and seventy eight (142 boys and 136 girls primary school children aged 7.9 ± 0.7 years participated in this study. Objective PA intensity and sedentary levels were measured over 7 days by accelerometry. Indices of total fat mass (body fat %, sum of skinfolds, fat distribution (waist-to-height ratio and muscular component (fat free mass [FFM] were calculated from measured anthropometric parameters. Results There were no differences (p > 0.05 in PA intensity levels and sedentary time between boys and girls as well as between NW and OW children. About 11 % of children met the current guidelines of at least 60 min per day of moderate-to-vigorous PA (MVPA. Sedentary time was positively and negatively associated (p < 0.05 with all body fat and FFM values, respectively. Moderate and vigorous PA along with MVPA were negatively and positively associated (p < 0.05 with all body fat and FFM indices, respectively. Conclusions The results of present study showed that about 11 % of primary school children were engaged in PA of at least 60 min of MVPA daily. While MVPA is negatively associated with fat mass indices and positively associated with FFM regardless of different

  11. Analysis of body composition and selected lipid parameters in healthy children – a preliminary report

    Directory of Open Access Journals (Sweden)

    Paweł Więch

    2017-09-01

    Full Text Available Aim: The aim of the study was to perform an analytical evaluation of body composition and selected lipid parameters in a population of healthy children. Material and methods: The study included a group of 81 children (44 boys and 37 girls, mean age 11.56 ± 2.84 years participating in a research project in the Centre for Medical and Natural Sciences Research and Innovation in Rzeszow. Body composition measurement (TANITA BC-420 S MA and lipid profile assessment (Cholestech LDX were performed in all patients. Statistical analysis of the collected material was conducted with Statistica 10.0 (StatSoft. Parametric and nonparametric tests were used for statistical analysis of variables. The level of statistical significance was adopted at p < 0.05. Results: A statistically significant difference in fat mass (p < 0.001, fat-free mass (p = 0.003, muscle mass (p = 0.003 and total body water (p < 0.001 was observed between children with normal body weight and overweight or obese children. A significant positive impact of FM (R = 0.09; p = 0.416 and a negative impact of total body water (R = −0.40; p < 0.001 on triglyceride parameters was demonstrated. Additionally, reduced fat mass correlated with a significant increase in high-density lipoprotein (R = −0.29; p = 0.009. Conclusions: The study demonstrated differences in the selected components of body composition in a population of healthy children, which allowed to precisely monitor the nutritional status when correlated with the results of lipid profile.

  12. Effects of pistachio nuts on body composition, metabolic, inflammatory and oxidative stress parameters in Asian Indians with metabolic syndrome: a 24-wk, randomized control trial.

    Science.gov (United States)

    Gulati, Seema; Misra, Anoop; Pandey, Ravindra Mohan; Bhatt, Surya Prakash; Saluja, Shelza

    2014-02-01

    The aim of this study was to evaluate the effects of pistachio nuts as an adjunct to diet and exercise on body composition, metabolic, inflammatory, and oxidative stress parameters in Asian Indians with metabolic syndrome. In this 24-wk randomized control trial, 60 individuals with the metabolic syndrome were randomized to either pistachio (intervention group) or control group (diet as per weight and physical activity profile, modulated according to dietary guidelines for Asian Indians) after 3 wk of a diet and exercise run in. In the first group, unsalted pistachios (20% energy) were given daily. A standard diet and exercise protocol was followed for both groups. Body weight, waist circumference (WC), magnetic resonance imaging estimation of intraabdominal adipose tissue and subcutaneous abdominal adipose tissue, fasting blood glucose (FBG), fasting serum insulin, glycosylated hemoglobin, lipid profile, high-sensitivity C-reactive protein (hs-CRP), adiponectin, free fatty acids (FFAs), tumor necrosis factor (TNF)-α, leptin, and thiobarbituric acid reactive substances (TBARS) were assessed before and after the intervention. Statistically significant improvement in mean values for various parameters in the intervention group compared with control group were as follows: WC (P pistachios leads to beneficial effects on the cardiometabolic profile of Asian Indians with metabolic syndrome. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Comparison of a new composite index based on midlatency auditory evoked potentials and electroencephalographic parameters with bispectral index (BIS) during moderate propofol sedation.

    Science.gov (United States)

    Hadzidiakos, D; Petersen, S; Baars, J; Herold, K; Rehberg, B

    2006-11-01

    Derived parameters of the electroencephalogram and auditory evoked potentials can be used to determine depth of anaesthesia and sedation. However, it is not known whether any parameter can identify the occurrence of awareness in individual patients. We have compared the performance of bispectral index and a new composite index derived from auditory evoked potentials and the electroencephalogram (AAI 1.61) in predicting consciousness, explicit and implicit memory during moderate sedation with propofol. Twenty-one patients with spinal anaesthesia received intraoperatively propofol at the age-corrected C(50) for loss of consciousness and were presented test words via headphones. Bispectral index and AAI 1.61 (auditory evoked potentials, AEP-Monitor2) were recorded in parallel as well as the Observer's Assessment of Alertness/Sedation-score. Postoperatively, testing for explicit and implicit memory formation was performed. Bispectral index and AAI 1.61 correlated well with loss of consciousness defined by an Observer's Assessment of Alertness/Sedation-score of 2 (identical P(K) of 0.87), but did not allow a prediction of postoperative explicit or implicit recall. Both bispectral index and AAI may be indices of depth of sedation rather than indicators of memory formation, which persists during propofol sedation even after loss of consciousness.

  14. Cariogenic potential of foods. II. Relationship of food composition, plaque microbial counts, and salivary parameters to caries in the rat model.

    Science.gov (United States)

    Mundorff-Shrestha, S A; Featherstone, J D; Eisenberg, A D; Cowles, E; Curzon, M E; Espeland, M A; Shields, C P

    1994-01-01

    A series of rat caries experiments was carried out to test the relative cariogenic potential and to identify the major carcinogenic elements of 22 popular snack foods. Parameters that were measured included rat caries, number of cariogenic bacteria in plaque, salivary parameters including flow rate, buffering capacity, total protein, lysozyme and amylase content, and composition of test foods including protein, fat, phosphorus, calcium, fluoride, galactose, glucose, total reducing sugar, sucrose, and starch. Many interesting relationships were observed between food components, numbers of plaque bacteria, salivary components, and specific types of carious lesions. Protein, fat, and phosphorus in foods were all associated with inhibition of both sulcal and buccolingual (smooth-surface) caries. Food fluoride was associated with inhibition of buccolingual caries, whereas calcium was related to inhibition of sulcal caries. Glucose, reducing sugar, and sucrose in foods were all related to promotion of both sulcal and smooth-surface caries. The numbers of Streptococcus sobrinus in plaque were associated with promotion of smooth-surface caries only, whereas lactobacilli, non-mutans bacteria, and total viable flora were related to promotion of both smooth-surface and sulcal caries. The salivary flow rate was associated with inhibition of both buccolingual and sulcal caries. Salivary buffering capacity (at pH 7) and salivary lysozyme delivery were associated with inhibition of number and severity of sulcal caries, while the salivary amylase content was related to the promotion of the number of sulcal lesions.

  15. Addition of wood chips in red wine during and after alcoholic fermentation: differences in color parameters, phenolic content and volatile composition

    Directory of Open Access Journals (Sweden)

    Maria Kyraleou

    2016-12-01

    Full Text Available The effect of the time of wood chip addition on phenolic content, color parameters and volatile composition of a red wine made by a native Greek variety (Agiorgitiko was evaluated. For this purpose, chips from American, French, Slavonia oak and Acacia were added in the wine during and after fermentation. Various chemical parameters of wines were studied after one, two and three months of contact with chips. The results showed that the addition of oak chips during alcoholic fermentation did not favor ellagitannin extraction and the reactions involved in tannin condensation and anthocyanin stabilization. Moreover, wines fermented with wood chips contained higher contents of whiskey lactones, eugenol, ethyl vanillate and acetate esters while their ethyl ester content was lower compared with the wines where chip addition took place after fermentation. Practical Application: The outcomes of this study would be of practical interest to winemakers since they could improve the control over the wood extraction process. When chips are added after fermentation wines seem to have a greater ageing potential compared to the wines fermented with chips due to their higher ellagitannin content and enhanced condensation reactions. On the other hand, color stabilization and tannin polymerization occur faster when chips are added during fermentation resulting in shorter ageing periods suitable for early consumed wines.

  16. Effects of intramammary infusion of sage (Salvia officinalis) essential oil on milk somatic cell count, milk composition parameters and selected hematology and serum biochemical parameters in Awassi sheep with subclinical mastitis.

    Science.gov (United States)

    Alekish, Myassar O; Ismail, Zuhair B; Awawdeh, Mofleh S; Shatnawi, Shoroq

    2017-08-01

    The aims of this study were to evaluate the effects of intramammary infusion of sage ( Salvia officinalis ) essential oil (EO) on milk somatic cell count (SCC), milk composition parameters and selected hematology and serum biochemical parameters in 20 Awassi ewes affected with subclinical mastitis. The dried leaves of sage were used to extract the EO by hydrodistillation. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of sage EO against Staphylococcus aureus were determined by the broth dilution method. Ewes were divided randomly into three main groups and received one of the following treatments; Group 1 (n=5): Dimethyl sulfoxide (DMSO) alone (5 ml; 0.2 ml of DMSO in 4.8 ml of saline), Group 2 (n=5): Amoxicillin alone (3 ml), and Group 3 (n=10): Sage EO (5 ml of sage EO solution [0.2 ml DMSO+1 ml EO+3.8 ml sterile saline]). All treatments were administered by intramammary infusion into each teat twice per day for 3 consecutive days. Milk samples for SCC and milk components determination and whole blood samples for hematology and serum biochemical analyses were collected before treatment (T0) and at 24 (T24) and 48 (T48) h after the last treatment. The MIC and MBC of sage EO against S. aureus were 12.5% and 6.1%, respectively. SCC was decreased significantly (psage EO and amoxicillin treated groups. Milk fat and lactose were increased significantly (psage EO and amoxicillin treated ewes while no significant changes were observed in the percentages of solids-not-fat, protein and total solids. No significant effects of sage EO treatment on any of the hematology or serum biochemical parameters were observed. There were no local or systemic side effects observed in any of the treated ewes. However, further clinical trials are warranted to determine safety and possible withdrawal times in milk before its recommendation for use in organic operations. In this study, the intramammary infusion of sage EO to ewes affected with

  17. Effect of Target Composition and Sputtering Deposition Parameters on the Functional Properties of Nitrogenized Ag-Permalloy Flexible Thin Films Deposited on Polymer Substrates

    Directory of Open Access Journals (Sweden)

    Waheed Khan

    2018-03-01

    Full Text Available We report the first results of functional properties of nitrogenized silver-permalloy thin films deposited on polyethylene terephthalic ester {PETE (C10H8O4n} flexible substrates by magnetron sputtering. These new soft magnetic thin films have magnetization that is comparable to pure Ni81Fe19 permalloy films. Two target compositions (Ni76Fe19Ag5 and Ni72Fe18Ag10 were used to study the effect of compositional variation and sputtering parameters, including nitrogen flow rate on the phase evolution and surface properties. Aggregate flow rate and total pressure of Ar+N2 mixture was 60 sccm and 0.55 Pa, respectively. The distance between target and the substrate was kept at 100 mm, while using sputtering power from 100–130 W. Average film deposition rate was confirmed at around 2.05 nm/min for argon atmosphere and was reduced to 1.8 nm/min in reactive nitrogen atmosphere. X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, vibrating sample magnetometer, and contact angle measurements were used to characterize the functional properties. Nano sized character of films was confirmed by XRD and SEM. It is found that the grain size was reduced by the formation of nitride phase, which in turns enhanced the magnetization and lowers the coercivity. Magnetic field coupling efficiency limit was determined from 1.6–2 GHz frequency limit. The results of comparable magnetic performance, lowest magnetic loss, and highest surface free energy, confirming that 15 sccm nitrogen flow rate at 115 W is optimal for producing Ag-doped permalloy flexible thin films having excellent magnetic field coupling efficiency.

  18. Evaluation of the contribution of chronic skin irritation and selected compositional parameters to the tumorigenicity of petroleum middle distillates in mouse skin.

    Science.gov (United States)

    Freeman, J J; Federici, T M; McKee, R H

    1993-07-28

    Two-year skin carcinogenicity studies were conducted in C3H mice to assess the effects of irritation and selected compositional parameters on the carcinogenic potential of four petroleum liquids. Three samples (lightly refined paraffinic oil, LRPO; lightly hydrodesulfurized specialty oil, LHSO; jet fuel, JF) can be generically classified as middle distillates, i.e. distillation occurs between 350 and 700 degrees F (175-370 degrees C). The fourth sample was a Steam Cracked Gas Oil (SCGO) that distilled within the same range. In studies that assess the effects of irritation on tumorigenicity, LRPO was tested undiluted or was diluted to 50% and 25% in either mineral oil (which eliminated irritation of the skin) or toluene (which did not). Undiluted LRPO elicited tumors in 8% of the mice. Both dilution procedures eliminated tumorigenic potential. Thus, it was possible to maintain a visible level of skin irritation equivalent to that elicited by undiluted LRPO without inducing tumors. SCGO elicited a chronic irritant state grossly equivalent to LRPO but was not tumorigenic. Jet Fuel A (JF) was tested undiluted using both a standard skin painting protocol and an intermittent dosing schedule in which treatment was suspended periodically to allow skin irritation to resolve. The standard treatment protocol of JF resulted in both marked skin irritation and tumors in 44% of the mice. However, using the intermittent schedule, the tumor yield was reduced to 2%. Collectively these data demonstrate that tumor formation is not a necessary sequelae to chronic skin irritation. Conversely, prevention of a marked chronic irritant state was accompanied by decreased tumor yield. These data suggest that the chronic irritant state may be a necessary but not sufficient condition for tumor formation. In studies to assess the effects of compositional parameters, a lightly hydrodesulfurized specialty oil (LHSO) similar to LRPO but refined to have negligible levels of sulfur compounds (3 ppm

  19. The Effects of an Olive Fruit Polyphenol-Enriched Yogurt on Body Composition, Blood Redox Status, Physiological and Metabolic Parameters and Yogurt Microflora.

    Science.gov (United States)

    Georgakouli, Kalliopi; Mpesios, Anastasios; Kouretas, Demetrios; Petrotos, Konstantinos; Mitsagga, Chrysanthi; Giavasis, Ioannis; Jamurtas, Athanasios Z

    2016-06-03

    In the present study we investigated the effects of an olive polyphenol-enriched yogurt on yogurt microflora, as well as hematological, physiological and metabolic parameters, blood redox status and body composition. In a randomized double-blind, crossover design, 16 (6 men, 10 women) nonsmoking volunteers with non-declared pathology consumed either 400 g of olive fruit polyphenol-enriched yogurt with 50 mg of encapsulated olive polyphenols (experimental condition-EC) or 400 g of plain yogurt (control condition-CC) every day for two weeks. Physiological measurements and blood collection were performed before and after two weeks of each condition. The results showed that body weight, body mass index, hip circumference and systolic blood pressure decreased significantly (p yogurt regardless of condition. A tendency towards significance for decreased levels of low density lipoprotein (LDL) cholesterol (p = 0.06) and thiobarbituric acid reactive substances (p yogurt consumption was observed. The population of lactic acid bacteria (LAB) and production of lactate in yogurt were significantly enhanced after addition of olive polyphenols, contrary to the population of yeasts and molds. The results indicate that consumption of the polyphenol-enriched yogurt may help individuals with non-declared pathology reduce body weight, blood pressure, LDL cholesterol levels and lipid peroxidation, and promote growth of beneficial LAB.

  20. Retention of aroma compounds: an interlaboratory study on the effect of the composition of food matrices on thermodynamic parameters in comparison with water.

    Science.gov (United States)

    Kopjar, Mirela; Andriot, Isabelle; Saint-Eve, Anne; Souchon, Isabelle; Guichard, Elisabeth

    2010-06-01

    Partition coefficients give an indication of the retention of aroma compounds by the food matrix. Data in the literature are obtained by various methods, under various conditions and expressed in various units, and it is thus difficult to compare the results. The aim of the present study was first to obtain gas/water and gas/matrix partition coefficients of selected aroma compounds, at different temperatures, in order to calculate thermodynamic parameters and second to compare the retention of these aroma compounds in different food matrices. Yogurts containing lipids and proteins induced a higher retention of aroma compounds than model gel matrices. The observed effects strongly depend on hydrophobicity of aroma compounds showing a retention for ethyl hexanoate and a salting out effect for ethyl acetate. A small but noticeable decrease in enthalpy of affinity is observed for ethyl butyrate and ethyl hexanoate between water and food matrices, suggesting that the energy needed for the volatilization is lower in matrices than in water. The composition and complexity of a food matrix influence gas/matrix partition coefficients or aroma compounds in function of their hydrophobicity and to a lower extent enthalpy of vaporization. Copyright (c) 2010 Society of Chemical Industry.

  1. Influence of Filler Alloy Composition and Process Parameters on the Intermetallic Layer Thickness in Single-Sided Cold Metal Transfer Welding of Aluminum-Steel Blanks

    Science.gov (United States)

    Silvayeh, Zahra; Vallant, Rudolf; Sommitsch, Christof; Götzinger, Bruno; Karner, Werner; Hartmann, Matthias

    2017-11-01

    Hybrid components made of aluminum alloys and high-strength steels are typically used in automotive lightweight applications. Dissimilar joining of these materials is quite challenging; however, it is mandatory in order to produce multimaterial car body structures. Since especially welding of tailored blanks is of utmost interest, single-sided Cold Metal Transfer butt welding of thin sheets of aluminum alloy EN AW 6014 T4 and galvanized dual-phase steel HCT 450 X + ZE 75/75 was experimentally investigated in this study. The influence of different filler alloy compositions and welding process parameters on the thickness of the intermetallic layer, which forms between the weld seam and the steel sheet, was studied. The microstructures of the weld seam and of the intermetallic layer were characterized using conventional optical light microscopy and scanning electron microscopy. The results reveal that increasing the heat input and decreasing the cooling intensity tend to increase the layer thickness. The silicon content of the filler alloy has the strongest influence on the thickness of the intermetallic layer, whereas the magnesium and scandium contents of the filler alloy influence the cracking tendency. The layer thickness is not uniform and shows spatial variations along the bonding interface. The thinnest intermetallic layer (mean thickness < 4 µm) is obtained using the silicon-rich filler Al-3Si-1Mn, but the layer is more than twice as thick when different low-silicon fillers are used.

  2. Effect of priming on growth, biochemical parameters and mineral composition of different cultivars of coriander (Coriandrum sativum L. under salt stress

    Directory of Open Access Journals (Sweden)

    Ben Fredj Meriem

    2014-08-01

    Full Text Available At Higher Institute of Agriculture of Chott Mariem, Sousse, Tunisia, this study was conducted to evaluate the interactive effect of salinity and seed priming on coriander. The experiment was carried out in completely randomized design with three replications consisting of four coriander genotypes (Tunisian cv, Algerian cv, Syrian cv and Egyptian cv at two seed conditions (seed priming with 4 g/l NaCl for 12h or no seed priming. Results revealed that seed priming and salinity had significantly (p≤0.05 affected all the parameters under study. On the first hand, salinity stress had adversely affected growth, chlorophyll content, mineral composition (K+ and Ca2+ of coriander in all genotypes. Also, it activated Na+ accumulation and synthesis of proline, soluble sugars and proteins. However, seed priming with NaCl had diminished the negative impact of salt stress in all cultivars and primed plants showed better response to salinity compared to unprimed plants. Maximum values were recorded in tolerant cultivar which is Tunisian one whereas minimum values were noted in sensitive cultivar (Algerian cv.

  3. The Effects of an Olive Fruit Polyphenol-Enriched Yogurt on Body Composition, Blood Redox Status, Physiological and Metabolic Parameters and Yogurt Microflora

    Directory of Open Access Journals (Sweden)

    Kalliopi Georgakouli

    2016-06-01

    Full Text Available In the present study we investigated the effects of an olive polyphenol-enriched yogurt on yogurt microflora, as well as hematological, physiological and metabolic parameters, blood redox status and body composition. In a randomized double-blind, crossover design, 16 (6 men, 10 women nonsmoking volunteers with non-declared pathology consumed either 400 g of olive fruit polyphenol-enriched yogurt with 50 mg of encapsulated olive polyphenols (experimental condition—EC or 400 g of plain yogurt (control condition—CC every day for two weeks. Physiological measurements and blood collection were performed before and after two weeks of each condition. The results showed that body weight, body mass index, hip circumference and systolic blood pressure decreased significantly (p < 0.05 following the two-week consumption of yogurt regardless of condition. A tendency towards significance for decreased levels of low density lipoprotein (LDL cholesterol (p = 0.06 and thiobarbituric acid reactive substances (p < 0.05 following two weeks of polyphenol-enriched yogurt consumption was observed. The population of lactic acid bacteria (LAB and production of lactate in yogurt were significantly enhanced after addition of olive polyphenols, contrary to the population of yeasts and molds. The results indicate that consumption of the polyphenol-enriched yogurt may help individuals with non-declared pathology reduce body weight, blood pressure, LDL cholesterol levels and lipid peroxidation, and promote growth of beneficial LAB.

  4. The Three-Month Effects of a Ketogenic Diet on Body Composition, Blood Parameters, and Performance Metrics in CrossFit Trainees: A Pilot Study

    Science.gov (United States)

    Kephart, Wesley C.; Pledge, Coree D.; Roberson, Paul A.; Mumford, Petey W.; Romero, Matthew A.; Mobley, Christopher B.; Young, Kaelin C.; Lowery, Ryan P.; Wilson, Jacob M.; Huggins, Kevin W.; Roberts, Michael D.

    2018-01-01

    Adopting low carbohydrate, ketogenic diets remains a controversial issue for individuals who resistance train given that this form of dieting has been speculated to reduce skeletal muscle glycogen levels and stifle muscle anabolism. We sought to characterize the effects of a 12-week ketogenic diet (KD) on body composition, metabolic, and performance parameters in participants who trained recreationally at a local CrossFit facility. Twelve participants (nine males and three females, 31 ± 2 years of age, 80.3 ± 5.1 kg body mass, 22.9 ± 2.3% body fat, 1.37 back squat: body mass ratio) were divided into a control group (CTL; n = 5) and a KD group (n = 7). KD participants were given dietary guidelines to follow over 12 weeks while CTL participants were instructed to continue their normal diet throughout the study, and all participants continued their CrossFit training routine for 12 weeks. Pre, 2.5-week, and 12-week anaerobic performance tests were conducted, and pre- and 12-week tests were performed for body composition using dual X-ray absorptiometry (DXA) and ultrasound, resting energy expenditure (REE), blood-serum health markers, and aerobic capacity. Additionally, blood beta hydroxybutyrate (BHB) levels were measured weekly. Blood BHB levels were 2.8- to 9.5-fold higher in KD versus CTL throughout confirming a state of nutritional ketosis. DXA fat mass decreased by 12.4% in KD (p = 0.053). DXA total lean body mass changes were not different between groups, although DXA dual-leg lean mass decreased in the KD group by 1.4% (p = 0.068), and vastus lateralis thickness values decreased in the KD group by ~8% (p = 0.065). Changes in fasting glucose, HDL cholesterol, and triglycerides were similar between groups, although LDL cholesterol increased ~35% in KD (p = 0.048). Between-group changes in REE, one-repetition maximum (1-RM) back squat, 400 m run times, and VO2peak were similar between groups. While our n-sizes were limited, these preliminary data suggest that

  5. The Three-Month Effects of a Ketogenic Diet on Body Composition, Blood Parameters, and Performance Metrics in CrossFit Trainees: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Wesley C. Kephart

    2018-01-01

    Full Text Available Adopting low carbohydrate, ketogenic diets remains a controversial issue for individuals who resistance train given that this form of dieting has been speculated to reduce skeletal muscle glycogen levels and stifle muscle anabolism. We sought to characterize the effects of a 12-week ketogenic diet (KD on body composition, metabolic, and performance parameters in participants who trained recreationally at a local CrossFit facility. Twelve participants (nine males and three females, 31 ± 2 years of age, 80.3 ± 5.1 kg body mass, 22.9 ± 2.3% body fat, 1.37 back squat: body mass ratio were divided into a control group (CTL; n = 5 and a KD group (n = 7. KD participants were given dietary guidelines to follow over 12 weeks while CTL participants were instructed to continue their normal diet throughout the study, and all participants continued their CrossFit training routine for 12 weeks. Pre, 2.5-week, and 12-week anaerobic performance tests were conducted, and pre- and 12-week tests were performed for body composition using dual X-ray absorptiometry (DXA and ultrasound, resting energy expenditure (REE, blood-serum health markers, and aerobic capacity. Additionally, blood beta hydroxybutyrate (BHB levels were measured weekly. Blood BHB levels were 2.8- to 9.5-fold higher in KD versus CTL throughout confirming a state of nutritional ketosis. DXA fat mass decreased by 12.4% in KD (p = 0.053. DXA total lean body mass changes were not different between groups, although DXA dual-leg lean mass decreased in the KD group by 1.4% (p = 0.068, and vastus lateralis thickness values decreased in the KD group by ~8% (p = 0.065. Changes in fasting glucose, HDL cholesterol, and triglycerides were similar between groups, although LDL cholesterol increased ~35% in KD (p = 0.048. Between-group changes in REE, one-repetition maximum (1-RM back squat, 400 m run times, and VO2peak were similar between groups. While our n-sizes were limited, these preliminary data suggest

  6. Optimization of process parameters and catalyst compositions in carbon dioxide oxidative coupling of methane over CaO-MnO/CeO{sub 2} catalyst using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Istadi,; Amin, Nor Aishah Saidina [Chemical Reaction Engineering Group (CREG), Faculty of Chemical and Natural Resources Engineering, Universiti Teknologi Malaysia, UTM Skudai, Johor Bahru (81310 Malaysia)

    2006-05-15

    The optimization of process parameters and catalyst compositions for the CO{sub 2} oxidative coupling of methane (CO{sub 2}-OCM) reaction over CaO-MnO/CeO{sub 2} catalyst was developed using Response Surface Methodology (RSM). The relationship between the responses, i.e. CH{sub 4} conversion, C{sub 2} hydrocarbons selectivity or yield, with four independent variables, i.e. CO{sub 2}/CH{sub 4} ratio, reactor temperature, wt.% CaO and wt.% MnO in the catalyst, were presented as empirical mathematical models. The maximum C{sub 2} hydrocarbons selectivity and yields of 82.62% and 3.93%, respectively, were achieved by the individual-response optimization at the corresponding optimal process parameters and catalyst compositions. However, the CH{sub 4} conversion was a saddle function and did not show a unique optimum as revealed by the canonical analysis. Moreover pertaining to simultaneous multi-responses optimization, the maximum C{sub 2} selectivity and yield of 76.56% and 3.74%, respectively, were obtained at a unique optimal process parameters and catalyst compositions. It may be deduced that both individual- and multi-responses optimizations are useful for the recommendation of optimal process parameters and catalyst compositions for the CO{sub 2}-OCM process. (author)

  7. Comparing the Effect of Fasting and Physical Activity on Active and Non-active Males’ Body Composition, Serum Osmolarity Levels and Some Parameters of Electrolytes

    Directory of Open Access Journals (Sweden)

    M Nematy

    2012-08-01

    Full Text Available Introduction: Ever since there is insufficient and incoherent information about the effect of the Ramadan Fasting together with regular exercise on levels of serum osmolarity, and electrolytes concentration. The aim of this study was to compare the effect of fasting and physical activity on active and non-active males’ body composition, serum osmolarity levels and some parameters of electrolytes. Methods: Twenty six healthy males, who were selected by convenience sampling method, were divided into two (active and non-active groups. The Active group participated in football training for three sessions per week during the fasting month. All measurements were repeated on the first and last day of fasting month and were used to analyze the test results. Results: The average differences were significantly decreased in weight, BMI, WHR, mineral, total water in two groups (P≤0.05. There was a significant difference in average of BMI, WHR, body fat, mineral and total water between two groups (P≤0.05. Within-group mean differences in glucose, potassium, urine and albumin in both groups were significant (P≤0.05. Differences of serum osmolarity in between- and within-groups were not significant in both groups. While, glucose decreased significantly, the levels of the protein decreased, and urea increased significantly only in non active fasting group. Conclusion: According to these results, regular exercise together with the Ramadan fasting result in change in some serum osmolarity index, electrolytes and water. Therefore, it is necessary to protect the athletics against the malnutrition in Ramadan fasting by using the diet schedule and enough water.

  8. Effects of buffering mineral mixtures on milk yield, milk composition, rumen pH and some blood biochemical parameters in heat stressed dairy cows

    Directory of Open Access Journals (Sweden)

    Adamović Milan

    2014-01-01

    group of cows, percentage of fat and dry substance in milk was significantly increased (p<0.05 and 0.01 respectively, while percentage of protein increase was insignificant. The substitution of magnesium oxide with bentonite had no impact on the values of examined parameters of metabolic profile, but it led to statistically significant increase of rumen contents pH values (p<0.05. From the obtained results it can be concluded that substitution of magnesium oxide with bentonite in feed mixtures that are used for feeding cows during summer period, can prevent rumen acidosis, which high yielding cows incline to under the conditions of elevated external temperatures. Besides that, this kind of substitution leads to improvement of milk composition, especially when percentage of fat and dry substance in milk is concerned. [Projekat Ministarstva nauke Republike Srbije, br. TR 31003 i br. TR 34013

  9. Estimation of transport parameters of phenolic compounds and inorganic contaminants through composite landfill liners using one-dimensional mass transport model

    International Nuclear Information System (INIS)

    Varank, Gamze; Demir, Ahmet; Yetilmezsoy, Kaan; Bilgili, M. Sinan; Top, Selin; Sekman, Elif

    2011-01-01

    Highlights: → We conduct 1D advection-dispersion modeling to estimate transport parameters. → We examine fourteen phenolic compounds and three inorganic contaminants. → 2-MP, 2,4-DCP, 2,6-DCP, 2,4,5-TCP, 2,3,4,6-TeCP have the highest coefficients. → Dispersion coefficients of Cu are determined to be higher than Zn and Fe. → Transport of phenolics can be prevented by zeolite and bentonite in landfill liners. - Abstract: One-dimensional (1D) advection-dispersion transport modeling was conducted as a conceptual approach for the estimation of the transport parameters of fourteen different phenolic compounds (phenol, 2-CP, 2-MP, 3-MP, 4-MP, 2-NP, 4-NP, 2,4-DNP, 2,4-DCP, 2,6-DCP, 2,4,5-TCP, 2,4,6-TCP, 2,3,4,6-TeCP, PCP) and three different inorganic contaminants (Cu, Zn, Fe) migrating downward through the several liner systems. Four identical pilot-scale landfill reactors (0.25 m 3 ) with different composite liners (R1: 0.10 + 0.10 m of compacted clay liner (CCL), L e = 0.20 m, k e = 1 x 10 -8 m/s, R2: 0.002-m-thick damaged high-density polyethylene (HDPE) geomembrane overlying 0.10 + 0.10 m of CCL, L e = 0.20 m, k e = 1 x 10 -8 m/s, R3: 0.002-m-thick damaged HDPE geomembrane overlying a 0.02-m-thick bentonite layer encapsulated between 0.10 + 0.10 m CCL, L e = 0.22 m, k e = 1 x 10 -8 m/s, R4: 0.002-m-thick damaged HDPE geomembrane overlying a 0.02-m-thick zeolite layer encapsulated between 0.10 + 0.10 m CCL, L e = 0.22 m, k e = 4.24 x 10 -7 m/s) were simultaneously run for a period of about 540 days to investigate the nature of diffusive and advective transport of the selected organic and inorganic contaminants. The results of 1D transport model showed that the highest molecular diffusion coefficients, ranging from 4.77 x 10 -10 to 10.67 x 10 -10 m 2 /s, were estimated for phenol (R4), 2-MP (R1), 2,4-DNP (R2), 2,4-DCP (R1), 2,6-DCP (R2), 2,4,5-TCP (R2) and 2,3,4,6-TeCP (R1). For all reactors, dispersion coefficients of Cu, ranging from 3.47 x 10 -6 m 2 /s to 5

  10. Critical parameters for electron beam curing of cationic epoxies and property comparison of electron beam cured cationic epoxies versus thermal cured resins and composites

    International Nuclear Information System (INIS)

    Janke, C.J.; Norris, R.E.; Yarborough, K.; Lopata, V.J.

    1997-01-01

    Electron beam curing of composites is a nonthermal, nonautoclave curing process offering the following advantages compared to conventional thermal curing: substantially reduced manufacturing costs and curing times; improvements in part quality and performance; reduced environmental and health concerns; and improvements in material handling. In 1994 a Cooperative Research and Development Agreement (CRADA), sponsored by the Department of Energy Defense Programs and 10 industrial partners, was established to advance electron beam curing of composites. The CRADA has successfully developed hundreds of new toughened and untoughened resins, offering unlimited formulation and processing flexibility. Several patent applications have been filed for this work. Composites made from these easily processable, low shrinkage material match the performance of thermal cured composites and exhibit: low void contents comparable to autoclave cured composites (less than 1%); superb low water absorption values in the same range as cyanate esters (less than 1%); glass transition temperatures rivaling those of polyimides (greater than 390 C); mechanical properties comparable to high performance, autoclave cured composites; and excellent property retention after cryogenic and thermal cycling. These materials have been used to manufacture many composite parts using various fabrication processes including hand lay-up, tow placement, filament winding, resin transfer molding and vacuum assisted resin transfer molding

  11. Impact of sampling depth and plant species on local environmental conditions, microbiological parameters and bacterial composition in a mercury contaminated salt marsh

    International Nuclear Information System (INIS)

    Cleary, D.F.R.; Oliveira, V.; Gomes, N.C.M.; Pereira, A.; Henriques, I.; Marques, B.; Almeida, A.; Cunha, A.; Correia, A.; Lillebø, A.I.

    2012-01-01

    Highlights: ► Vegetated habitat contained distinct bacterial communities. ► Variation in bacterial composition with depth differed between plant species. ► There is evidence of an effect of mercury concentration on bacterial composition. ► Depth and sampling depth explained almost 70% of the variation in bacterial composition. - Abstract: We compare the environmental characteristics and bacterial communities associated with two rushes, Juncus maritimus and Bolboschoenus maritimus, and adjacent unvegetated habitat in a salt marsh subjected to historical mercury pollution. Mercury content was higher in vegetated than unvegetated habitat and increased with sampling depth. There was also a significant relationship between mercury concentration and bacterial composition. Habitat (Juncus, Bolboschoenus or unvegetated), sample depth, and the interaction between both, however, explained most of the variation in composition (∼70%). Variation in composition with depth was most prominent for the unvegetated habitat, followed by Juncus, but more constrained for Bolboschoenus habitat. This constraint may be indicative of a strong plant–microbe ecophysiological adaptation. Vegetated habitat contained distinct bacterial communities associated with higher potential activity of aminopeptidase, β-glucosidase and arylsulphatase and incorporation rates of 14 C-glucose and 14 C-acetate. Communities in unvegetated habitat were, in contrast, associated with both higher pH and proportion of sulphate reducing bacteria.

  12. Development of an in-situ synthesized multi-component reinforced Al–4.5%Cu–TiC metal matrix composite by FAS technique – Optimization of process parameters

    Directory of Open Access Journals (Sweden)

    Biswajit Das

    2016-03-01

    Full Text Available In the present investigation, an in-situ multi-component reinforced aluminium copper alloy based metal matrix composite was fabricated by the flux assisted synthesis (FAS technique. It was found from the optical microscopy analysis that TiC particles are formed in the composite. Further the present research investigates the feasibility and dry machining characteristics of Al–4.5%Cu/5TiC metal matrix composite in CNC milling machine using uncoated solid carbide end mill cutter. The effect of the machining parameters such as feed, cutting speed, depth of cut on the response parameters such as cutting force and COM is determined by using analysis of variance (ANOVA. From the analysis it was found that cutting speed and depth of cut played a major role in affecting cutting force. Multi output optimization of the process was carried out by the application of the Taguchi method with fuzzy logic, and the confirmatory test has revealed the accuracy of the developed model. For predicting the response parameters, regression equations were developed and verified with a number of test cases and it was observed that the percentage error for both responses is less than ±3%, which indicates there is a close agreement between the predicted and the measured results.

  13. Effect of the cationic composition of sorption solution on the quantification of sorption-desorption parameters of heavy metals in soils

    International Nuclear Information System (INIS)

    Sastre, J.; Rauret, G.; Vidal, M.

    2006-01-01

    We obtained the sorption isotherms of Cd, Cu, Pb and Zn in clay, clay saline and organic soils. The distribution coefficients (K d ) were determined in 0.02 eq l -1 CaCl 2 and in a solution that simulated the soil solution cationic composition. The K d values greatly varied with the composition of the sorption solution and the initial metal concentration. The sorption experiments were complemented with the quantification of the extractable metal, to estimate the reversibility of metal sorption. The extraction yields depended on the metal-soil combination, and the initial metal concentration, showing no correlation with previous K d values. The effect of the solution composition in mobility predictions was estimated through a Retention Factor, defined as the ratio of the K d versus the extraction yield. Results showed that risk was over- or underestimated using the CaCl 2 medium in soils with a markedly different soil solution composition. - Sorption solution composition modifies metal sorption-desorption pattern in soils

  14. THE EFFECT OF VARIOUS PARAMETERS ON DRY SLIDING WEAR BEHAVIOR AND SUBSURFACE OF AGED HYBRID METAL MATRIX COMPOSITES USING TAGUCHI TECHNIQUE

    Directory of Open Access Journals (Sweden)

    B.M. Viswanatha

    2017-06-01

    Full Text Available The effects of applied load, sliding speed and sliding distance on the dry sliding wear behavior of aged Al-SiCp-Gr composites were investigated. The specimen were fabricated by stir-casting technique. The pin-on-disc wear testing machine was used to investigate the wear rate by design of experiments based on L27 using Taguchi technique. Sliding distance was the most important variable that influenced the wear rate followed by sliding speed and applied load. The worn out surfaces were analyzed by SEM and EDS to study the subsurface mechanism of wear. The addition of reinforcements showed improved tribological behavior of the composite than base alloy.

  15. Kinetic Rate Law Parameter Measurements on a Borosilicate Waste Glass: Effect of Temperature, pH, and Solution Composition on Alkali Ion Exchange

    International Nuclear Information System (INIS)

    Pierce, Eric M.; McGrail, B PETER.; Icenhower, J P.; Rodriguez, Elsa A.; Steele, Jackie L.; Baum, Steven R.

    2004-01-01

    The reaction kinetics of glass is controlled by matrix dissolution and ion exchange (IEX). Dissolution of an alkali-rich simulated borosilicate waste glass was investigated using single-pass flow-through (SPFT) experiments. Experiments were conducted as a function of temperature, pH, and solution composition by varying the SiO 2 (aq) activity in the influent solution. Results showed that under dilute conditions matrix dissolution increased with increasing pH and temperature, and decreased with increasing SiO 2 (aq) activity. IEX rates decreased with increasing pH and temperature, and increased with increasing SiO 2 (aq) activity. Over the solution composition range interrogated in this study the dominant dissolution mechanism changed from matrix dissolution to IEX. These results suggest that ''secondary'' reactions may become dominant under certain environmental conditions and emphasize the need to incorporate these reactions into dissolution rate models

  16. The influence of the carbon surface chemical composition on Dubinin-Astakhov equation parameters calculated from SF{sub 6} adsorption data-grand canonical Monte Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Furmaniak, Sylwester; Terzyk, Artur P; Gauden, Piotr A [Department of Chemistry, Physicochemistry of Carbon Materials Research Group, N Copernicus University, Gagarin Street 7, 87-100 Torun (Poland); Kowalczyk, Piotr [Nanochemistry Research Institute, Curtin University, PO Box U1987, Perth, WA 6845 (Australia); Harris, Peter J F, E-mail: aterzyk@chem.uni.torun.pl [Centre for Advanced Microscopy, University of Reading, Whiteknights, Reading RG6 6AF (United Kingdom)

    2011-10-05

    Using grand canonical Monte Carlo simulation we show, for the first time, the influence of the carbon porosity and surface oxidation on the parameters of the Dubinin-Astakhov (DA) adsorption isotherm equation. We conclude that upon carbon surface oxidation, the adsorption decreases for all carbons studied. Moreover, the parameters of the DA model depend on the number of surface oxygen groups. That is why in the case of carbons containing surface polar groups, SF{sub 6} adsorption isotherm data cannot be used for characterization of the porosity. (paper)

  17. On the Role of Processing Parameters in Producing Recycled Aluminum AA6061 Based Metal Matrix Composite (MMC-AlR) Prepared Using Hot Press Forging (HPF) Process.

    Science.gov (United States)

    Ahmad, Azlan; Lajis, Mohd Amri; Yusuf, Nur Kamilah

    2017-09-19

    Solid-state recycling, which involves the direct recycling of scrap metal into bulk material using severe plastic deformation, has emerged as a potential alternative to the conventional remelting and recycling techniques. Hot press forging has been identified as a sustainable direct recycling technique that has fewer steps and maintains excellent material performance. An experimental investigation was conducted to explore the hardness and density of a recycled aluminum-based metal matrix composite by varying operating temperature and holding time. A mixture of recycled aluminum, AA6061, and aluminum oxide were simultaneously heated to 430, 480, and 530 °C and forged for 60, 90, and 120 min. We found a positive increase in microhardness and density for all composites. The hardness increased approximately 33.85%, while density improved by about 15.25% whenever the temperature or the holding time were increased. Based on qualitative analysis, the composite endures substantial plastic deformation due to the presence of hardness properties due to the aluminum oxide embedded in the aluminum matrix. These increases were significantly affected by the operating temperature; the holding time also had a subordinate role in enhancing the metal matrix composite properties. Furthermore, in an effort to curb the shortage of primary resources, this study reviewed the promising performance of secondary resources produced by using recycled aluminum and aluminum oxide as the base matrix and reinforcement constituent, respectively. This study is an outline for machining practitioners and the manufacturing industry to help increase industry sustainability with the aim of preserving the Earth for our community in the future.

  18. Composition of fatty acids in the maternal and umbilical cord plasma of adolescent and adult mothers: relationship with anthropometric parameters of newborn

    OpenAIRE

    Oliveira, Ol?via RC; Santana, Michelle G; Santos, Fl?via S; Concei??o, Felipe D; Sardinha, F?tima LC; Veiga, Gl?ria V; Tavares do Carmo, Maria G

    2012-01-01

    Abstract Background Considering the importance of long chain polyunsaturated fatty acids to fetal development and the lack of studies that have compared the status of fatty acids between adolescents and adults mothers, the purpose of this study was to evaluate the composition of fatty acids in maternal and umbilical cord plasma from adolescent and adults mothers. Methods Forty pregnant adolescents and forty pregnant adults were selected to assess the distribution profile of fatty acids in the...

  19. On the Role of Processing Parameters in Producing Recycled Aluminum AA6061 Based Metal Matrix Composite (MMC-AlR Prepared Using Hot Press Forging (HPF Process

    Directory of Open Access Journals (Sweden)

    Azlan Ahmad

    2017-09-01

    Full Text Available Solid-state recycling, which involves the direct recycling of scrap metal into bulk material using severe plastic deformation, has emerged as a potential alternative to the conventional remelting and recycling techniques. Hot press forging has been identified as a sustainable direct recycling technique that has fewer steps and maintains excellent material performance. An experimental investigation was conducted to explore the hardness and density of a recycled aluminum-based metal matrix composite by varying operating temperature and holding time. A mixture of recycled aluminum, AA6061, and aluminum oxide were simultaneously heated to 430, 480, and 530 °C and forged for 60, 90, and 120 min. We found a positive increase in microhardness and density for all composites. The hardness increased approximately 33.85%, while density improved by about 15.25% whenever the temperature or the holding time were increased. Based on qualitative analysis, the composite endures substantial plastic deformation due to the presence of hardness properties due to the aluminum oxide embedded in the aluminum matrix. These increases were significantly affected by the operating temperature; the holding time also had a subordinate role in enhancing the metal matrix composite properties. Furthermore, in an effort to curb the shortage of primary resources, this study reviewed the promising performance of secondary resources produced by using recycled aluminum and aluminum oxide as the base matrix and reinforcement constituent, respectively. This study is an outline for machining practitioners and the manufacturing industry to help increase industry sustainability with the aim of preserving the Earth for our community in the future.

  20. Investigation on the effect of Friction Stir Processing Parameters on Micro-structure and Micro-hardness of Rice Husk Ash reinforced Al6061 Metal Matrix Composites

    Science.gov (United States)

    Fatchurrohman, N.; Farhana, N.; Marini, C. D.

    2018-03-01

    Friction stir processing (FSP) is an alternative way to produce the surface composites of aluminium alloy in order to modify the microstructure and improve the mechanical properties. In this experiment, Al6061 aluminium alloy has been chosen to be used as the matrix base plate for the FSP. Al606 has potential for the use in advanced application but it has low wear resistance. While, the reinforced used was rice husk ash (RHA) in order to produce surface composites which increased the micro hardness of the plate composites. The Al6061 was stirred individually and with 5 weight % of RHA at three different tool rotational speeds of 800 rpm, 1000 rpm and 1200 rpm. After running the FSP, the result in the distribution of particles and the micro hardness of the specimens were identified. The result showed that Al6061 plate with the existing 5 weight % of RHA reinforced at the highest of tool rotational speeds of 1200rpm has the best distribution of particles and the highest result in average of micro hardness with 80Hv.

  1. Effect of compositional dependence on physical and optical parameters of Te{sub 17}Se{sub 83−x}Bi{sub x} glassy system

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Pankaj, E-mail: pks_phy@yahoo.co.in [Department of Physics and Materials Science, Jaypee University of Information Technology, Waknaghat, Solan, HP 173234 (India); El-Bana, M.S.; Fouad, S.S. [Nano-Science and Semiconductor Laboratories, Department of Physics, Faculty of Education, Ain Shams University, Cairo (Egypt); Sharma, Vineet [Department of Physics and Materials Science, Jaypee University of Information Technology, Waknaghat, Solan, HP 173234 (India)

    2016-05-15

    In the present paper we have studied the effect of Bi addition on the physical and optical properties of thermally evaporated Te{sub 17}Se{sub 83−x}Bi{sub x} thin films. With Bi addition the density, mean coordination number, mechanical constraints, glass transition temperature increases. The other parameters theoretical energy gap, lone pair electron, deviation from stoichiometry decreases. Transmission spectra have been taken in the spectral range 400 nm–2500 nm using ultraviolet–visible–near infrared spectrophotometer. The fundamental absorption edge shifts towards longer wavelength with Bi incorporation. Optical energy gap and linear refractive index have been determined using transmission spectra. A good correlation has been drawn between the optical and theoretical parameters. Using linear optical parameters, the nonlinear optical susceptibility and nonlinear refractive index have been estimated. - Highlights: • Physical and optical parameters have been analyzed for Te{sub 17}Se{sub 83−x}Bi{sub x} glassy alloys. • The addition of Bi leads to decrease of average heat of atomization and cohesive energy. • The optical band gap decreases with increasing Bi content. • The third order susceptibility and nonlinear refractive index show an increase with increase in the Bi content.

  2. Association Study of Polymorphisms in the SOST Gene Region and Parameters of Bone Strength and Body Composition in Both Young and Elderly Men: Data from the Odense Androgen Study

    DEFF Research Database (Denmark)

    Piters, Elke; de Freitas, Fenna; Nielsen, Torben Leo

    2011-01-01

    By means of different genetic association studies the SOST gene, encoding sclerostin, has repeatedly been suggested to regulate bone mineral density (BMD) and osteoporosis susceptibility. This study aimed at a further understanding of the importance of two previously studied single...... at several sites and additionally for body composition and hip geometric parameters. In a combined analysis of the young and the elderly OAS, no associations were found for SRP3 either with BMD or with hip geometry. Instead, we found that this polymorphism had a relatively large effect on weight (-1.149 kg...... effect of the minor allele (C). No age-specific effects were found for either of the two SNPs. In summary, we are the first to find interesting associations between SRP3 and body composition. For SRP9, we replicated a site-specific association with femoral neck BMD. In addition, we report a novel...

  3. Effects of Processing Parameters on the Fabrication of in-situ Al/TiC Composites by Thermally Activated Combustion Reaction Process in an Aluminium Melt using Al-TiO_2-C Powder Mixtures

    International Nuclear Information System (INIS)

    Kim, Hwa-Jung; Lee, Jung-Moo; Cho, Young-Hee; Kim, Jong-Jin; Kim, Su-Hyeon; Lee, Jae-Chul

    2012-01-01

    A feasible way to fabricate in-situ Al/TiC composites was investigated. An elemental mixture of Al-TiO_2-C pellet was directly added into an Al melt at 800-920°C to form TiC by self-combustion reaction. The addition of CuO initiates the self-combustion reaction to form TiC in 1-2 um at the melt temperature above 850°C. Besides the CuO addition, a diluent element of excess Al plays a significant role in the TiC formation by forming a precursor phase, Al_3Ti. Processing parameters such as CuO content, the amount of excess Al and the melt temperature, have affected the combustion reaction and formation of TiC, and their influences on the microstructures of in-situ Al/TiC composites are examined.

  4. Effect of processing parameters on the formation of C{sub f}/LAS composites/Ag−Cu−Ti/TC4 brazed joint

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Duo; Niu, Hongwei [Shandong Provincial Key Laboratory of Special Welding Technology, Harbin Institute of Technology at Weihai, Weihai 264209 (China); Liu, Jihou [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Song, Xiaoguo, E-mail: songxg@hitwh.edu.cn [Shandong Provincial Key Laboratory of Special Welding Technology, Harbin Institute of Technology at Weihai, Weihai 264209 (China); State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Xia, Long [School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209 (China); Feng, Jicai [Shandong Provincial Key Laboratory of Special Welding Technology, Harbin Institute of Technology at Weihai, Weihai 264209 (China); State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China)

    2016-10-15

    C{sub f}/LAS composites were successfully jointed to TC4 alloy with Ag−Cu−Ti filler by vacuum brazing. The interfacial microstructure of TC4/C{sub f}/LAS composites joints was characterized by employing scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-diffraction (XRD) and transmission electron microscopy (TEM). The determination of the thin interfacial reaction layer (TiSi{sub 2} + TiC layer) was realized by TEM. The effect of holding time on the interfacial microstructure and shear strength were investigated. With the increasing holding time, the thickness of diffusion layer, Ti{sub 3}Cu{sub 4} layer, and TiSi{sub 2} + TiC layer increased obviously, on the contrary, that of Ti−Cu intermetallic compound layers decreased gradually. Besides, blocky Ti{sub 3}Cu{sub 4} phase was coarsened when the joint was brazed at 890 °C for 20 min, which deteriorated the mechanical properties of the joint dramatically. The interfacial evolution of TC4/C{sub f}/LAS composites joint and the formation of TiSi{sub 2}, TiC, Ti{sub 3}Cu{sub 4}, TiCu and Ti{sub 2}Cu phases were expounded. The maximum shear strength of 26.4 MPa was obtained when brazed at 890 °C for 10 min. - Highlights: •The thin interface reaction layer was determined to be TiSi{sub 2} + TiC layer by TEM. •Holding time had influence on the interfacial microstructure and joint properties. •Microstructural evolution mechanism and reactions of brazed joints were expounded.

  5. Consuming a balanced high fat diet for 16 weeks improves body composition, inflammation and vascular function parameters in obese premenopausal women.

    Science.gov (United States)

    Silver, Heidi J; Kang, Hakmook; Keil, Charles D; Muldowney, James A; Kocalis, Heidi; Fazio, Sergio; Vaughan, Douglas E; Niswender, Kevin D

    2014-04-01

    Inflammation, insulin resistance and vascular dysfunction characterize obesity and predict development of cardiovascular disease (CVD). Although women experience CVD events at an older age, vascular dysfunction is evident 10years prior to coronary artery disease. Questions remain whether replacing SFA entirely with MUFA or PUFA is the optimal approach for cardiometabolic benefits. This study tested the hypotheses that: a) body composition, inflammation and vascular function would improve with a high fat diet (HFD) when type of fat is balanced as 1/3 SFA, 1/3 MUFA and 1/3 PUFA; and b) body composition, inflammation and vascular function would improve more when balanced HFD is supplemented with 18C fatty acids, in proportion to the degree of 18C unsaturation. Obese premenopausal women were stabilized on balanced HFD and randomized to consume 9g/d of encapsulated stearate (18:0), oleate (18:1), linoleate (18:2) or placebo. Significant improvements occurred in fat oxidation rate (↑6%), body composition (%fat: ↓2.5±2.1%; %lean: ↑2.5±2.1%), inflammation (↓ IL-1α, IL-1β, 1L-12, Il-17, IFNγ, TNFα, TNFβ) and vascular function (↓BP, ↓PAI-1, ↑tPA activity). When compared to HFD+placebo, HFD+stearate had the greatest effect on reducing IFNγ (↓74%) and HFD+linoleate had the greatest effect on reducing PAI-1 (↓31%). Balancing the type of dietary fat consumed (SFA/MUFA/PUFA) is a feasible strategy to positively affect markers of CVD risk. Moreover, reductions in inflammatory molecules involved in vascular function might be enhanced when intake of certain 18C fatty acids is supplemented. Long term effects need to be determined for this approach. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. CONSUMING A BALANCED HIGH FAT DIET FOR 16 WEEKS IMPROVES BODY COMPOSITION, INFLAMMATION AND VASCULAR FUNCTION PARAMETERS IN OBESE PREMENOPAUSAL WOMEN

    Science.gov (United States)

    Silver, Heidi J.; Kang, Hakmook; Keil, Charles D.; Muldowney, James A.; Kocalis, Heidi; Fazio, Sergio; Vaughan, Douglas E.; Niswender, Kevin D.

    2014-01-01

    Objective Inflammation, insulin resistance and vascular dysfunction characterize obesity and predict development of cardiovascular disease (CVD). Although women experience CVD events at an older age, vascular dysfunction is evident 10 years prior to coronary artery disease. Questions remain whether replacing SFA entirely with MUFA or PUFA is the optimal approach for cardiometabolic benefits. This study tested the hypotheses that: a) body composition, inflammation and vascular function would improve with a high fat diet (HFD) when type of fat is balanced as 1/3 SFA, 1/3 MUFA and 1/3 PUFA; and b) body composition, inflammation and vascular function would improve more when balanced HFD is supplemented with 18C fatty acids, in proportion to the degree of 18C unsaturation. Methods Obese premenopausal women were stabilized on balanced HFD and randomized to consume 9 g/d of encapsulated stearate (18:0), oleate (18:1), linoleate (18:2) or placebo. Results Significant improvements occurred in fat oxidation rate (↑6%), body composition (%fat: ↓2.5 ± 2.1%; %lean: ↑2.5 ± 2.1%), inflammation (↓ IL-1α, IL-1β, 1L-12, Il-17, IFNγ, TNFα, TNFβ) and vascular function (↓BP, ↓PAI-1, ↑tPA activity). When compared to HFD+placebo, HFD+stearate had the greatest effect on reducing IFNγ (↓74%) and HFD+linoleate had the greatest effect on reducing PAI-1 (↓31%). Conclusions Balancing the type of dietary fat consumed (SFA/MUFA/PUFA) is a feasible strategy to positively affect markers of CVD risk. Moreover, reductions in inflammatory molecules involved in vascular function might be enhanced when intake of certain 18C fatty acids is supplemented. Long term effects need to be determined for this approach. PMID:24559846

  7. [Determination of deuterium concentration in foods and influence of water with modified isotopic composition on oxidation parameters and heavy hydrogen isotopes content in experimental animals].

    Science.gov (United States)

    Basov, A A; Bykov, I M; Baryshev, M G; Dzhimak, S S; Bykov, M I

    2014-01-01

    The article presents the results of the study of the deuterium (D) content in food products as well as the influence of deuterium depleted water (DDW) on the concentration of heavy hydrogen isotopes in the blood and lyophilized tissues of rats. The most significant difference in the content of D was found between potato and pork fat, which indexes the standard delta notation (δ) D in promille, related to the international standard SMOW (Standard Mean Ocean of Water) amounted to -83,2 per thousand and -250,7 per thousand, respectively (phydrogen atoms in the body. The data obtained in the experimental modeling of the diet of male Wistar rats in the age of 5-6 mo (weight 235 ± 16 g) using DDW (δD = -743,2 per thousand) instead of drinking water (δD = -37,0 per thousand) with identical mineral composition showed that after 2 weeks significant (p tissue") is due to different rates ofisotopic exchange reactions in plasma and tissues (liver, kidney, heart), which can be explained by entering into the composition of a modified diet of organic substrates with more than DDW concentration D, which are involved in the construction of cellular structures and eventually lead to a redistribution of D and change direction of D/H gradient "plasmacomposition, aimed at reducing the level of heavy non-radioactive atoms will allow the targeted nutritional correction of prooxidant-antioxidant status of the population in areas with adverse environmental conditions, stimulating by created isotopic D/H gradient cytoprotective mechanisms influencing the various components of nonspecific protection, including free radical oxidation processes. And then again, periodic assessment of the isotopic composition of nutrients will monitor the quality of food consumed by the population, and if

  8. Small changes in environmental parameters lead to alterations in antibiotic resistance, cell morphology and membrane fatty acid composition in Staphylococcus lugdunensis.

    Directory of Open Access Journals (Sweden)

    Marcus J Crompton

    Full Text Available Staphylococcus lugdunensis has emerged as a major cause of community-acquired and nosocomial infections. This bacterium can rapidly adapt to changing environmental conditions to survive and capitalize on opportunities to colonize and infect through wound surfaces. It was proposed that S. lugdunensis would have underlying alterations in metabolic homeostasis to provide the necessary levels of adaptive protection. The aims of this project were to examine the impacts of subtle variations in environmental conditions on growth characteristics, cell size and membrane fatty acid composition in S. lugdunensis. Liquid broth cultures of S. lugdunensis were grown under varying combinations of pH (6-8, temperature (35-39°C and osmotic pressure (0-5% sodium chloride w/w to reflect potential ranges of conditions encountered during transition from skin surfaces to invasion of wound sites. The cells were harvested at the mid-exponential phase of growth and assessed for antibiotic minimal inhibitory concentration (MIC, generation time, formation of small colony variants, cell size (by scanning electron microscopy and membrane fatty acid composition. Stress regimes with elevated NaCl concentrations resulted in significantly higher antibiotic resistance (MIC and three of the combinations with 5% NaCl had increased generation times (P<0.05. It was found that all ten experimental growth regimes, including the control and centroid cultures, yielded significantly different profiles of plasma membrane fatty acid composition (P<0.0001. Alterations in cell size (P<0.01 were also observed under the range of conditions with the most substantial reduction occurring when cells were grown at 39°C, pH 8 (514±52 nm, mean ± Standard Deviation compared with cells grown under control conditions at 37°C with pH 7 (702±76 nm, P<0.01. It was concluded that S. lugdunensis responded to slight changes in environmental conditions by altering plasma membrane fatty acid composition

  9. Effects of dietary peppermint (Mentha piperita) on growth performance, chemical body composition and hematological and immune parameters of fry Caspian white fish (Rutilus frisii kutum).

    Science.gov (United States)

    Adel, Milad; Abedian Amiri, Armin; Zorriehzahra, Jalil; Nematolahi, Amin; Esteban, Maria Ángeles

    2015-08-01

    Peppermint (Mentha piperita L.) is a very popular herb. While numerous effects have been described in mammals, its effects on fish have received so far limited attention. The effects of dietary administration of peppermint on fry Caspian white fish (Rutilus frisii kutum) were studied. Fish were divided into 4 groups before being fed diets supplemented with 0% (control), 1%, 2% and 3% of peppermint extracts for 8 weeks. Dose-dependent increases of growth parameters (WG and SGR), mucus skin (protein concentration, alkaline phosphatase and antimicrobial activity) and seric (lysozyme and IgM) and blood leucocyte respiratory burst activities and different hematological parameters (number of red and white cells, seric hemoglobin and hematocrit content) were recorded in fry fish fed supplemented diets. However, the dietary peppermint supplements have different effects on the number of blood leucocytes depending on the leucocyte cell type. While no significant differences were observed in the number of blood monocytes and eosinophils, the number of neutrophils and lymphocytes was increased and decreased, respectively, on fish fed peppermint enriched diets, respect to the values found in control fish. Present results corroborate that dietary administration of peppermint promotes growth performance and increases the main hematological and immune humoral (both mucosal and systemic) parameters of fry Caspian white fish. This study may provide new applications of peppermint and, at the same time, promote rational development and utilization of peppermint resources. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Effect of high-fat diets on body composition, lipid metabolism and insulin sensitivity, and the role of exercise on these parameters

    Directory of Open Access Journals (Sweden)

    D.F. Coelho

    2011-10-01

    Full Text Available Dietary fat composition can interfere in the development of obesity due to the specific roles of some fatty acids that have different metabolic activities, which can alter both fat oxidation and deposition rates, resulting in changes in body weight and/or composition. High-fat diets in general are associated with hyperphagia, but the type of dietary fat seems to be more important since saturated fats are linked to a positive fat balance and omental adipose tissue accumulation when compared to other types of fat, while polyunsaturated fats, omega-3 and omega-6, seem to increase energy expenditure and decrease energy intake by specific mechanisms involving hormone-sensitive lipase, activation of peroxisome proliferator-activated receptor α (PPARα and others. Saturated fat intake can also impair insulin sensitivity compared to omega-3 fat, which has the opposite effect due to alterations in cell membranes. Obesity is also associated with impaired mitochondrial function. Fat excess favors the production of malonyl-CoA, which reduces GLUT4 efficiency. The tricarboxylic acid cycle and beta-oxidation are temporarily uncoupled, forming metabolite byproducts that augment reactive oxygen species production. Exercise can restore mitochondrial function and insulin sensitivity, which may be crucial for a better prognosis in treating or preventing obesity.

  11. Effects of free-range access on production parameters and meat quality, composition and taste in slow-growing broiler chickens.

    Science.gov (United States)

    Stadig, Lisanne M; Rodenburg, T Bas; Reubens, Bert; Aerts, Johan; Duquenne, Barbara; Tuyttens, Frank A M

    2016-12-01

    Demand for meat from free-range broiler chickens is increasing in several countries. Consumers are motivated by better animal welfare and other product attributes such as quality and taste. However, scientific literature is not unanimous about whether free-range access influences quality, composition, and taste of the meat. Because chickens normally do not use free-range areas optimally, it is possible that provision of more suitable shelter will lead to more pronounced differences between chickens raised indoors and outdoors. In this study, an experiment with 2 production rounds of 600 slow-growing broilers each was performed. In each round, 200 chickens were raised indoors (IN), 200 had free-range access to grassland with artificial shelter (AS), and 200 had free-range access to short-rotation coppice with willow (SRC). Free-range use, feed intake, and growth were monitored, and after slaughter (d72) meat quality, composition, and taste were assessed. Free-range use was higher in SRC than in AS chickens (42.8 vs. 35.1%, P free-range access was darker (P = 0.021) and yellower (P = 0.001) than that of IN chickens. Ultimate pH was lower (5.73 vs. 5.79; P = 0.006) and drip loss higher (1.29 vs. 1.09%; P = 0.05) in IN versus AS chickens. The percentage of polyunsaturated fatty acids was higher in AS than in IN meat (35.84 vs. 34.59%; P = 0.021). The taste panel judged breast meat of SRC chickens to be more tender (P = 0.003) and less fibrous (P = 0.013) compared to that of AS and IN chickens, and juicier compared to the IN chickens (P = 0.017). Overall, free-range access negatively affected slaughter weight, but positively affected meat quality, taste, and composition. Only a few differences between AS and SRC were found, possibly due to limited differences in free-range use. © 2016 Poultry Science Association Inc.

  12. Association study of common variants in the sFRP1 gene region and parameters of bone strength and body composition in two independent healthy Caucasian male cohorts

    DEFF Research Database (Denmark)

    Boudin, Eveline; Piters, Elke; Fransen, Erik

    2012-01-01

    has an influence on bone formation. Therefore this study aimed to investigate the effect of common genetic variation on BMD and bone strength in Caucasian men of different ages. Using HapMap we selected 13 tagSNPs which tag most common genetic variation in and around sFRP1 and we genotyped these SNPs...... parameters. Based on the results of the young cohort we selected three SNPs for further analysis in the complete OAS population. To conclude we tried to replicate the results of two SNPs in an independent population of 994 Belgian men. We found a strong association for rs9694405 with BMI as well in both...

  13. The effects of castration on the growth parameters, carcass yield and meat chemical composition of intensively reared Common Pheasant (Phasianus colchicus colchicus L.

    Directory of Open Access Journals (Sweden)

    Renata Baric-Rafaj

    2010-01-01

    Full Text Available The effects of castration on growth performance, carcass characteristics and chemical composition of m. iliotibilais cranialis and m. pectoralis superficialis of pheasants were examined. Forty pheasants reared in commercial pheasantry were included in the experiment. Half of the pheasants were castrated at 8 weeks of age. Values for live weight tended to be higher in castrated pheasants in the 24th week (P<0.1 and values for weight gain were significantly higher between the 16th and 24th weeks (P<0.05. Feed-to-gainratio (8th – 32nd week was significantly better (P<0.05 in castrated pheasants. Eviscerated weight and dressing percentage at 32nd week were not significantly different between treatments. The chemical composition of m. iliotibilais cranialis and m. pectoralis superficialis showed significantly higher values of fat (P<0.01 and moisture (P<0.05 in castrated pheasants in comparison with intact ones. Protein content of both muscles was higher in intact pheasants (P<0.05. Body part weights were not influenced by the treatment with the exception of heart weight, which was significantly higher in the intact pheasants (P<0.05. We concluded that castration tended to improve growth performance only in the first 24 weeks of the fattening period and, therefore, continuation of fattening after that period is no longer feasible. The most important characteristic of the castrated pheasant’s meat was an increased amount of fat. More studies under different feeding and alternative breeding systems are necessary to improve production.

  14. Effects of a mini-trampoline rebounding exercise program on functional parameters, body composition and quality of life in overweight women.

    Science.gov (United States)

    Cugusi, Lucia; Manca, Andrea; Serpe, Roberto; Romita, Giovanni; Bergamin, Marco; Cadeddu, Christian; Solla, Paolo; Mercuro, Giuseppe

    2018-03-01

    Mini-trampoline rebounding exercise (MRE) is becoming a very popular form of fitness training. Despite awareness of this activity worldwide, a limited number of studies have systematically investigated the health effects correlated with MRE training. The aim of our study was to evaluate manifold health outcomes after 12 weeks of an MRE program in a group of overweight Italian women. Eighteen overweight women (age 38.05±10.5 years, BMI: 27.6±2.1 kg/m2) were enrolled in this study. Functional profile, strength, body composition, quality of life and pain intensity were assessed at baseline and after 12 weeks of MRE. Significant improvements were observed in the measurements of anthropometric profile and body composition (circumferences, fat mass, lean and muscular mass). Both a significant decrease in systolic and diastolic blood pressure values (from 128/80.5 to 123/71 mmHg, P<0.05) and an improvement in lipid and glucose profiles were observed. At maximal exercise testing, an increase in work capacity (from 104 to 123 watts, P=0.003) and VO2max (from 15.4 to 16.9 mL/kg/min, P=0.04) was found. SF-36 showed positive changes in four of the eight items as well as in the Mental Component Summary. With regard to the Brief Pain Inventory-SF, a decrease in both pain severity and the pain interference score was detected. MRE appears feasible to ensure positive effects on overall health and can be proposed to populations that could greatly benefit from training programs, such as overweight women.

  15. Long-term lifestyle intervention with optimized high-intensity interval training improves body composition, cardiometabolic risk, and exercise parameters in patients with abdominal obesity.

    Science.gov (United States)

    Gremeaux, Vincent; Drigny, Joffrey; Nigam, Anil; Juneau, Martin; Guilbeault, Valérie; Latour, Elise; Gayda, Mathieu

    2012-11-01

    The aim of this study was to study the impact of a combined long-term lifestyle and high-intensity interval training intervention on body composition, cardiometabolic risk, and exercise tolerance in overweight and obese subjects. Sixty-two overweight and obese subjects (53.3 ± 9.7 yrs; mean body mass index, 35.8 ± 5 kg/m(2)) were retrospectively identified at their entry into a 9-mo program consisting of individualized nutritional counselling, optimized high-intensity interval exercise, and resistance training two to three times a week. Anthropometric measurements, cardiometabolic risk factors, and exercise tolerance were measured at baseline and program completion. Adherence rate was 97%, and no adverse events occurred with high-intensity interval exercise training. Exercise training was associated with a weekly energy expenditure of 1582 ± 284 kcal. Clinically and statistically significant improvements were observed for body mass (-5.3 ± 5.2 kg), body mass index (-1.9 ± 1.9 kg/m(2)), waist circumference (-5.8 ± 5.4 cm), and maximal exercise capacity (+1.26 ± 0.84 metabolic equivalents) (P high-density lipoprotein ratio were also significantly improved (P body mass and waist circumference loss were baseline body mass index and resting metabolic rate; those for body mass index decrease were baseline waist circumference and triglyceride/high-density lipoprotein cholesterol ratio. A long-term lifestyle intervention with optimized high-intensity interval exercise improves body composition, cardiometabolic risk, and exercise tolerance in obese subjects. This intervention seems safe, efficient, and well tolerated and could improve adherence to exercise training in this population.

  16. Parameter Estimation

    DEFF Research Database (Denmark)

    Sales-Cruz, Mauricio; Heitzig, Martina; Cameron, Ian

    2011-01-01

    of optimisation techniques coupled with dynamic solution of the underlying model. Linear and nonlinear approaches to parameter estimation are investigated. There is also the application of maximum likelihood principles in the estimation of parameters, as well as the use of orthogonal collocation to generate a set......In this chapter the importance of parameter estimation in model development is illustrated through various applications related to reaction systems. In particular, rate constants in a reaction system are obtained through parameter estimation methods. These approaches often require the application...... of algebraic equations as the basis for parameter estimation.These approaches are illustrated using estimations of kinetic constants from reaction system models....

  17. Multivariate optimization of process parameters in the synthesis of calcined Ca‒Al (NO3) LDH for defluoridation using 3(3) factorial, central composite and Box-Behnken design.

    Science.gov (United States)

    Ghosal, Partha S; Gupta, Ashok K; Sulaiman, Ayoob

    2016-01-01

    Response surface methodology was applied for the first time in the optimization of the preparation of layered double hydroxide (LDH) for defluoridation. The influence of three vital process parameters (viz. pH, molar ratio and calcination temperature) in the synthesis of the adsorbent 'Calcined Ca‒Al (NO3) LDH' was thoroughly examined to maximize its fluoride scavenging potential. The process parameters were optimized using the 3(3) factorial, face centered central composite and Box-Behnken designs and a comparative assessment of the methods was conducted. The maximum fluoride removal efficiency was achieved at a calcination temperature of approximately 500ºC; however, the efficiency decreased with increasing pH and molar ratio. The outcome of the comparative assessment clearly delineates the case specific nature of the models. A better predictability over the entire experimental domain was obtained with the 3(3) factorial method, whereas the Box-Behnken design was found to be the most efficient model with lesser number of experimental runs. The desirability function technique was performed for optimizing the response, wherein face centered central composite design exhibited a maximum desirability. The calcined Ca‒Al (NO3) LDH, synthesized under the optimum conditions, demonstrated the removal efficiencies of 95% and 99% for the doses of 3 g L(-1) and 5 g L(-1), respectively.

  18. Investigation on the parameter optimization and performance of laser cladding a gradient composite coating by a mixed powder of Co50 and Ni/WC on 20CrMnTi low carbon alloy steel

    Science.gov (United States)

    Shi, Yan; Li, Yunfeng; Liu, Jia; Yuan, Zhenyu

    2018-02-01

    In this study, a gradient composite coating was manufactured on 20CrMnTi alloy steel by laser cladding. The laser power, cladding scan velocity and powder flow rate were selected as influencing factors of the orthogonal cladding experiments. The influencing factors were optimized by the comprehensive analysis of Taguchi OA and TOPSIS method. The high significant parameters and the predicted results were confirmed by the ANOVA method. The macromorphology and microstructures are characterized by using laser microscope, SEM, XRD and microhardness tester. Comparison tests of wear resistance of gradient composite coating, 20CrMnTi cemented quenching sample and the 20CrMnTi sample were conducted on the friction-wear tester. The results show that the phases are γ-Co solid solution, Co3B, M23C6 and etc. The interlayers and wear-resisting layer also contain new hard phases as WC, W2C. The microhardness of the gradient coating was increased to 3 times as compared with that of the 20CrMnTi substrate. The wear resistance of the gradient composite coating and 20CrMnTi cemented quenching sample was enhanced to 36.4 and 15.9 times as compared with that of the 20CrMnTi.

  19. Determination of two-liquid mixture composition by assessing its dielectric parameters 2. modified measuring system for monitoring the dehydration process of bioethanol production

    Directory of Open Access Journals (Sweden)

    Vilitis O.

    2014-02-01

    Full Text Available In Part 2 of the work we describe a modified measuring system for precise monitoring of the dehydration process of bioethanol production. This is based on the earlier proposed system for measuring the concentration of solutions and two-liquid mixtures using devices with capacitive sensors (1-300pF, which provides a stable measuring resolution of ± 0.005 pF at measuring the capacitance of a sensor. In this part of our work we determine additional requirements that are to be imposed on the measuring system at monitoring the ethanol dehydration process and control of bioethanol production. The most important parameters of the developed measuring system are identified. An exemplary calculation is given for the thermocompensated calibration of measuring devices. The results of tests have shown a good performance of the developed measuring system.

  20. Composition of fatty acids in the maternal and umbilical cord plasma of adolescent and adult mothers: relationship with anthropometric parameters of newborn

    Directory of Open Access Journals (Sweden)

    Oliveira Olívia RC

    2012-11-01

    Full Text Available Abstract Background Considering the importance of long chain polyunsaturated fatty acids to fetal development and the lack of studies that have compared the status of fatty acids between adolescents and adults mothers, the purpose of this study was to evaluate the composition of fatty acids in maternal and umbilical cord plasma from adolescent and adults mothers. Methods Forty pregnant adolescents and forty pregnant adults were selected to assess the distribution profile of fatty acids in the maternal and umbilical cord plasma. Quantification of fatty acids in the total lipids of the sample groups was performed through the use of gas-liquid chromatography. Results The maternal and umbilical cord plasma of the adolescents showed a greater concentration of AA than did that of the adults (P  Conclusions This suggests that in situations of greater nutritional risk, as in adolescent pregnancy, n-3PUFA concentrations have a greater influence on the proper development of newborns. Moreover, variations in fatty acid concentrations in the maternal and cord plasma of adolescents and adults may indicate that pregnancy affects the LC-PUFA status of adults and adolescents in distinct ways.

  1. Yield, flesh parameters, and proximate and fatty acid composition in muscle tissue of wild and cultured Vieja Colorada (Cichlasoma festae) in tropical Ecuadorian river

    International Nuclear Information System (INIS)

    González, M.A.; Angón, E.; Rodríguez, J.; Moya, A.; García, A.; Peña, F.

    2017-01-01

    This study was conducted to determine the composition of cultured and wild Cichlasoma festae in Ecuador. The mean slaughter yield and dress-out were similar for cultured and wild specimens and the average fillet fat content for cultured fish was significantly higher compared to the wild fish. The pH, fillet color, drip loss and coked loss were similar between populations. Significant differences were found in protein, lipid and ash content in both studied populations. This study showed that saturated fatty acid (SFA) was higher than sum of monounsaturated (MUFA) and polyunsaturated fatty acid (PUFA) in both populations. Palmitic, oleic and linoleic acids had the maximum percentage of SFA, MUFA and PUFA respectively. In cultured and wild fish was also found to differ in the PUFA/SFA, docosahexaenoic acid/eicosapentaenoic acid, n-3/n-6 ratios and atherogenicity and thrombogenicity indices. Minerals included Ca, P, K, Mg, Zn, Fe, Cu and Mn. There were significant differences in the first six ones. The production system (cultured or wild) influences significantly most of the analyzed characteristics of carcass and flesh of C. festae. These results provide valued nutritional information of native species to produce sources of food with low-fat and high-protein, and safety food for the consumers in Ecuadorian country.

  2. Formation of Load Parameters of Destroyed Massife in Explosion of Multicharge Composition with Separation of its Parts by Profile Inert Interval

    Science.gov (United States)

    Paramonov, G. P.; Mysin, A. V.; Babkin, R. S.

    2017-10-01

    The paper introduces construction of multicharge composition with separation of parts by the profile inert interval. On the basis of the previous researches, the pulse-forming process at explosion of the borehole multicharge taking into account the offered design is considered. The physical model for definition of reflected wavelet taking into account an increment of radius of cross section of a charging cavity and the expiration of detonation products is offered. A technique is developed for numerical modeling of gas-dynamic processes in a borehole with a change in the axial channel of a profile inert interval caused by a high-temperature flow of gaseous products of an explosion. The authors obtained the dependence of the change in mean pressure on the borehole wall on time for each of the parts of the multicharge. To blast a series of charges of the proposed design, taking into account optimization of the stress fields of neighboring charges, the delay interval is determined for a short-delayed explosion.

  3. Effects of dietary dandelion extracts on growth performance, body composition, plasma biochemical parameters, immune responses and disease resistance of juvenile golden pompano Trachinotus ovatus.

    Science.gov (United States)

    Tan, Xiaohong; Sun, Zhenzhu; Chen, Shu; Chen, Silin; Huang, Zhong; Zhou, Chuanpeng; Zou, Cuiyun; Liu, Qingying; Ye, Huaqun; Lin, Heizhao; Ye, Chaoxia; Wang, Anli

    2017-07-01

    The present study was conducted to investigate the effects of dietary dandelion extracts (DE) supplementation on growth performance, feed utilization, body composition, plasma biochemical indices, immune responses, hepatic antioxidant abilities, and resistance to the pathogen Vibrio harveyi in Trachinotus ovatus. A basal diet supplemented with DE at 0, 0.50, 1.00, 2.00, 4.00 and 10.00 g kg -1 were fed to golden pompano for 8 weeks. The study indicated that dietary supplementation with DE could significantly improve final body weight (FBW), weight gain rate (WGR), specific growth rate (SGR), feed efficiency ratio (FER), feed intake (FI), protein efficiency ratio (PER) and protein deposit rate (PDR) (P Vibrio harveyi, significant higher post-challenge survival was observed in fish fed DE supplement (P growth performance, feed utilization, body protein deposit, immune ability, hepatic and plasma antioxidative enzyme activities and improve its resistance to infection by Vibrio harveyi. Copyright © 2017. Published by Elsevier Ltd.

  4. Yield, flesh parameters, and proximate and fatty acid composition in muscle tissue of wild and cultured Vieja Colorada (Cichlasoma festae) in tropical Ecuadorian river

    Energy Technology Data Exchange (ETDEWEB)

    González, M.A.; Angón, E.; Rodríguez, J.; Moya, A.; García, A.; Peña, F.

    2017-07-01

    This study was conducted to determine the composition of cultured and wild Cichlasoma festae in Ecuador. The mean slaughter yield and dress-out were similar for cultured and wild specimens and the average fillet fat content for cultured fish was significantly higher compared to the wild fish. The pH, fillet color, drip loss and coked loss were similar between populations. Significant differences were found in protein, lipid and ash content in both studied populations. This study showed that saturated fatty acid (SFA) was higher than sum of monounsaturated (MUFA) and polyunsaturated fatty acid (PUFA) in both populations. Palmitic, oleic and linoleic acids had the maximum percentage of SFA, MUFA and PUFA respectively. In cultured and wild fish was also found to differ in the PUFA/SFA, docosahexaenoic acid/eicosapentaenoic acid, n-3/n-6 ratios and atherogenicity and thrombogenicity indices. Minerals included Ca, P, K, Mg, Zn, Fe, Cu and Mn. There were significant differences in the first six ones. The production system (cultured or wild) influences significantly most of the analyzed characteristics of carcass and flesh of C. festae. These results provide valued nutritional information of native species to produce sources of food with low-fat and high-protein, and safety food for the consumers in Ecuadorian country.

  5. Comparison of fermentation of diets of variable composition and microbial populations in the rumen of sheep and Rusitec fermenters. I. Digestibility, fermentation parameters, and microbial growth.

    Science.gov (United States)

    Martínez, M E; Ranilla, M J; Tejido, M L; Ramos, S; Carro, M D

    2010-08-01

    Four ruminally and duodenally cannulated sheep and 8 Rusitec fermenters were used to determine the effects of forage to concentrate (F:C) ratio and type of forage in the diet on ruminal fermentation and microbial protein synthesis. The purpose of the study was to assess how closely fermenters can mimic the dietary differences found in vivo. The 4 experimental diets contained F:C ratios of 70:30 or 30:70 with either alfalfa hay or grass hay as the forage. Microbial growth was determined in both systems using (15)N as a microbial marker. Rusitec fermenters detected differences between diets similar to those observed in sheep by changing F:C ratio on pH; neutral detergent fiber digestibility; total volatile fatty acid concentrations; molar proportions of acetate, propionate, butyrate, isovalerate, and caproate; and amylase activity. In contrast, Rusitec fermenters did not reproduce the dietary differences found in sheep for NH(3)-N and lactate concentrations, dry matter (DM) digestibility, proportions of isobutyrate and valerate, carboxymethylcellulase and xylanase activities, and microbial growth and its efficiency. Regarding the effect of the type of forage in the diet, Rusitec fermenters detected differences between diets similar to those found in sheep for most determined parameters, with the exception of pH, DM digestibility, butyrate proportion, and carboxymethylcellulase activity. Minimum pH and maximal volatile fatty acid concentrations were reached at 2h and at 6 to 8h postfeeding in sheep and fermenters, respectively, indicating that feed fermentation was slower in fermenters compared with that in sheep. There were differences between systems in the magnitude of most determined parameters. In general, fermenters showed lower lactate concentrations, neutral detergent fiber digestibility, acetate:propionate ratios, and enzymatic activities. On the contrary, fermenters showed greater NH(3)-N concentrations, DM digestibility, and proportions of propionate

  6. Changes in growth, physiological parameters and the hormonal status of Myrtus communis L. plants irrigated with water with different chemical compositions.

    Science.gov (United States)

    Acosta-Motos, José Ramón; Ortuño, María Fernanda; Álvarez, Sara; López-Climent, María Fernanda; Gómez-Cadenas, Aurelio; Sánchez-Blanco, María Jesús

    2016-02-01

    Myrtus communis, an important Mediterranean ornamental shrub, was used to study the effect of irrigation water with different chemical compositions in the plant response. A treatment with NaCl was used to establish the plant resistance to high salinity at long term. Plants were subjected to four irrigation treatments with drainage for three months: Control (0.8 dS m(-1)); two treatments using reclaimed water (RWs): RW1 (2.0 dS m(-1)) and RW2 (5.0 dS m(-1)); and NaCl (10.0 dS m(-1)). High levels of electric conductivity of RWs not affected plant growth, while NaCl decreased leaf dry weight. Coinciding with the accumulation of Na(+) and Cl(-) in the roots, soil water potential decreased, which hinders the mobilization of water to the leaves, decreasing leaf water potential. The osmotic adjustment in the NaCl treatment was due to Na(+) and Cl(-) ions, although the proline could contribute as an Osmo compatible solute, increasing the turgor plants. Also changes in cell walls rigidity minimize the negative effects on the water balance; however, a higher lipid peroxidation was observed in these plants. Stomatal closure was associated with a decrease in K(+) and an increase in abscisic acid. NaCl produced an increase in salicylic acid and did not affect jasmonic acid contents at the end of the experiment. Similar behavior in soil and leaf water potentials, although less pronounced than in NaCl, was shown in RW2 plants. The abscisic acid increased in the RW2 with respect to the control and a decrease in stomatal conductance was observed at the end of the experiment. Plants irrigated with RW1 behaved similarly to the control. Copyright © 2015. Published by Elsevier GmbH.

  7. The Effect of Normally Consumed Amounts of Sucrose or High Fructose Corn Syrup on Lipid Profiles, Body Composition and Related Parameters in Overweight/Obese Subjects

    Directory of Open Access Journals (Sweden)

    Joshua Lowndes

    2014-03-01

    Full Text Available The American Heart Association (AHA has advocated that women and men not consume more than 100 and 150 kcal/day, respectively, from added sugars. These levels are currently exceeded by over 90% of the adult population in the United States. Few data exist on longer-term metabolic effects when sucrose and High Fructose Corn Syrup (HFCS, the principal sources of added dietary sugars, are consumed at levels typical of the general population. Sixty five overweight and obese individuals were placed on a eucaloric (weight stable diet for 10-weeks, which incorporated sucrose- or HFCS-sweetened, low-fat milk at 10% or 20% of calories in a randomized, double-blinded study. All groups responded similarly (interaction p > 0.05. There was no change in body weight in any of the groups over the 10-week study, or in systolic or diastolic blood pressure. Likewise, there were no changes in total cholesterol, triglycerides, low-density lipoprotein (LDL, or apolipoprotein B (Apo B. We conclude that (1 when consumed as part of a eucaloric diet fructose—when given with glucose (as normally consumed does not promote weight gain or an atherogenic lipid profile even when consumed at two to four times the level recently recommended by the AHA. (2 There were no differences between HFCS and sucrose on these parameters.

  8. The effect of normally consumed amounts of sucrose or high fructose corn syrup on lipid profiles, body composition and related parameters in overweight/obese subjects.

    Science.gov (United States)

    Lowndes, Joshua; Sinnett, Stephanie; Pardo, Sabrina; Nguyen, Von T; Melanson, Kathleen J; Yu, Zhiping; Lowther, Britte E; Rippe, James M

    2014-03-17

    The American Heart Association (AHA) has advocated that women and men not consume more than 100 and 150 kcal/day, respectively, from added sugars. These levels are currently exceeded by over 90% of the adult population in the United States. Few data exist on longer-term metabolic effects when sucrose and High Fructose Corn Syrup (HFCS), the principal sources of added dietary sugars, are consumed at levels typical of the general population. Sixty five overweight and obese individuals were placed on a eucaloric (weight stable) diet for 10-weeks, which incorporated sucrose- or HFCS-sweetened, low-fat milk at 10% or 20% of calories in a randomized, double-blinded study. All groups responded similarly (interaction p > 0.05). There was no change in body weight in any of the groups over the 10-week study, or in systolic or diastolic blood pressure. Likewise, there were no changes in total cholesterol, triglycerides, low-density lipoprotein (LDL), or apolipoprotein B (Apo B). We conclude that (1) when consumed as part of a eucaloric diet fructose--when given with glucose (as normally consumed) does not promote weight gain or an atherogenic lipid profile even when consumed at two to four times the level recently recommended by the AHA. (2) There were no differences between HFCS and sucrose on these parameters.

  9. The influence of inoculum composition on selected bioactive and nutritional parameters of grass pea tempeh obtained by mixed-culture fermentation with Rhizopus oligosporus and Aspergillus oryzae strains.

    Science.gov (United States)

    Starzynska-Janiszewska, A; Stodolak, B; Dulinski, R; Mickowska, B

    2012-04-01

    Tempeh is a popular Indonesian product obtained from legume seeds by solid-state fermentation with Rhizopus sp. The aim of this research was to study the effect of simultaneous mixed-culture fermentation of grass pea seeds on selected parameters of products as compared to traditional tempeh. The inoculum contained different ratios of Rhizopus oligosporus and Aspergillus oryzae spores. The simultaneous fermentation of grass pea seeds with inoculum consisting of 1.2 × 10(6) R. oligosporus and 0.6 × 10(6) A. oryzae spores (per 60 g of seeds) resulted in a product of improved quality, as compared with traditionally made tempeh (obtained after inoculation with 1.2 × 10(6) R. oligosporus spores), at the same fermentation time. This product had radical scavenging ability 70% higher than the one obtained with pure R. oligosporus culture and contained 2.23 g/kg dm of soluble phenols. The thiamin and riboflavin levels were above three (340 µg/g dm) and two (50.50 µg/g dm) folds higher than in traditionally made tempeh, respectively. The product had 65% in vitro bioavailability of proteins and 33% in vitro bioavailability of sugars. It also contained 40% less 3-N-oxalyl-L-2, 3-diaminopropionic acid (0.074 g/kg dm), as compared to traditional tempeh.

  10. Iodine and Selenium Biofortification with Additional Application of Salicylic Acid Affects Yield, Selected Molecular Parameters and Chemical Composition of Lettuce Plants (Lactuca sativa L. var. capitata)

    Science.gov (United States)

    Smoleń, Sylwester; Kowalska, Iwona; Czernicka, Małgorzata; Halka, Mariya; Kęska, Kinga; Sady, Włodzimierz

    2016-01-01

    Iodine (I) and selenium (Se) are included in the group of beneficial elements. They both play important roles in humans and other animals, particularly in the regulation of thyroid functioning. A substantial percentage of people around the world suffer from health disorders related to the deficiency of these elements in the diet. Salicylic acid (SA) is a compound similar to phytohormones and is known to improve the efficiency of I biofortification of plants. The influence of SA on Se enrichment of plants has not, however, been recognized together with its effect on simultaneous application of I and Se to plants. Two-year studies (2014–2015) were conducted in a greenhouse with hydroponic cultivation of lettuce in an NFT (nutrient film technique) system. They included the application of I (as KIO3), Se (as Na2SeO3) and SA into the nutrient solution. KIO3 was used at a dose of 5 mg I⋅dm-3 (i.e., 39.4 μM I), while Na2SeO3 was 0.5 mg Se⋅dm-3 (i.e., 6.3 μM Se). SA was introduced at three doses: 0.1, 1.0, and 10.0 mg⋅dm-3 nutrient solutions, equivalent to 0.724, 7.24, and 72.4 μM SA, respectively. The tested combinations were as follows: (1) control, (2) I + Se, (3) I + Se + 0.1 mg SA⋅dm-3, (4) I + Se + 1.0 mg SA⋅dm-3 and (5) I + Se + 10.0 mg SA⋅dm-3. The applied treatments had no significant impact on lettuce biomass (leaves and roots). Depending on the dose, a diverse influence of SA was noted with respect to the efficiency of I and Se biofortification; chemical composition of leaves; and mineral nutrition of lettuce plants, including the content of macro- and microelements and selenocysteine methyltransferase (SMT) gene expression. SA application at all tested doses comparably increased the level of selenomethionine (SeMet) and decreased the content of SA in leaves. PMID:27803709

  11. Longitudinal Effects of Iron Deficiency Anemia and Subsequent Repletion on Blood Parameters and the Rate and Composition of Growth in Pigs

    Directory of Open Access Journals (Sweden)

    Laura C. Knight

    2018-05-01

    Full Text Available Iron deficiency is reported as the most common nutrient deficiency worldwide. Due to rapid growth, infants are at particular risk for developing iron deficiency, which can easily progress to iron deficiency anemia (IDA, if not treated. The aim of this study was to determine the lasting effects of an early-life iron deficiency after a period of dietary iron repletion. Forty-two intact male pigs were fed, ad libitum, either control (CONT, 21.3 mg Fe/L or iron-deficient (ID 2.72 mg Fe/L milk replacer from postnatal day (PND 2 to 32 (phase 1. From PND 33 to 61 (phase 2, all pigs were transitioned onto a series of industry-standard, iron-adequate diets. Blood was collected weekly from PND 7 to 28, and again on PND 35 and 56, and tissues were collected at either PND 32 or PND 61. At the end of phase 1, ID pigs exhibited reduced hematocrit (Hct; p < 0.0001 and hemoglobin (Hb; p < 0.0001 compared with CONT pigs, but neither Hct (p = 0.5968 nor Hb (p = 0.6291 differed between treatment groups after dietary iron repletion at the end of phase 2. Body weight gain was reduced (p < 0.0001 58% at PND 32 in ID pigs compared with CONT pigs during phase 1, and this effect remained significant at the end of phase 2 (p = 0.0001, with ID pigs weighing 34% less than CONT pigs at PND 61. Analysis of peripheral protein and messenger RNA (mRNA gene expression biomarkers yielded inconclusive results, as would be expected based on previous biomarker analyses across multiple species. These findings suggest that early-life iron status negatively influences blood parameters and growth performance, with dietary iron repletion allowing for full recovery of hematological outcomes, but not growth performance.

  12. The tracer function of isotope composition and deuterium excess parameter of water bodies on prospecting for geothermal water: taking the prospecting for geothermal water in Sanjianshui, Sichuan for example

    International Nuclear Information System (INIS)

    Yang Bo; Yin Guan

    2003-01-01

    Based on the isotope composition features of water bodies in Sanjiashui area, this paper use the theory of deuterium excess parameter (d) to discuss and cause of formulation, recharge source, removed patch, detained time and dynamics feature on ground water. These discussed problems have far-reaching meaning on evaluating the size of geothermal water, exploited potential of thermal spring and find new thermal spring in neighboring area. We analyze the relation of d and tritium content (T) on different water bodies in Sanjianshui area and draw some conclusions. Firstly, all water bodies in Sanjianshui origin from precipitation. Secondly, precipitation of northwest mountain area that have long removed patch and long detained time is the recharge resource of groundwater in basin. In addition, we demonstrate the possibility of existence of geothermal water in several positions of Sanjianshui area. (authors)

  13. Inventory parameters

    CERN Document Server

    Sharma, Sanjay

    2017-01-01

    This book provides a detailed overview of various parameters/factors involved in inventory analysis. It especially focuses on the assessment and modeling of basic inventory parameters, namely demand, procurement cost, cycle time, ordering cost, inventory carrying cost, inventory stock, stock out level, and stock out cost. In the context of economic lot size, it provides equations related to the optimum values. It also discusses why the optimum lot size and optimum total relevant cost are considered to be key decision variables, and uses numerous examples to explain each of these inventory parameters separately. Lastly, it provides detailed information on parameter estimation for different sectors/products. Written in a simple and lucid style, it offers a valuable resource for a broad readership, especially Master of Business Administration (MBA) students.

  14. Effects of chemical composition and test parameters on the hot ductility of C-Mn-Al steels; Efeito da composicao quimica e parametros de ensaios sobre a ductilidade a quente de acos C-Mn-Al

    Energy Technology Data Exchange (ETDEWEB)

    Macedo, Marcelo C.S. de; Comineli, Osvaldo G; Pancieri, Jose G.P.; Oliveira, Maria A.L. de [Espirito Santo Univ., Vitoria, ES (Brazil). Dept. de Engenharia Mecanica; Souza Lima Cardoso, Geraldo I. de [Companhia Siderurgica de Tubarao (CST), Serra, ES (Brazil); Mintz, Barry [The City Univ., London (United Kingdom)

    1987-12-31

    The effects of Al content, as well as hot tensile test parameters on hot ductility of two C-Mn-Al steels are presented. Thermal cycle were carried out to study the influence of thermal oscillations during those compositions cooling, consisting of heating the samples up to a solubilization temperature, high enough to dissolve any phase which could possibly be present in the original ingot, and also to produce a coarser grain size. After 5 minutes at 1330 deg C, the steels were cooled in three different ways to reach test temperature and samples remain at this temperature for 5 minutes for stabilization before testing. Further, a preliminary comparison between hot ductility results, obtained when samples are molten and continuously cooled at two different rates, and those obtained for solution treated samples which are cooled at an intermediate cooling rate. For the two composition solution treated, a ductility was observed trough displaced from each other about 50 deg C, being the Al content the responsible for this difference. (author) 14 refs., 11 figs., 1 tab.

  15. Metronidazole removal in powder-activated carbon and concrete-containing graphene adsorption systems: Estimation of kinetic, equilibrium and thermodynamic parameters and optimization of adsorption by a central composite design.

    Science.gov (United States)

    Manjunath, S V; Kumar, S Mathava; Ngo, Huu Hao; Guo, Wenshan

    2017-12-06

    Metronidazole (MNZ) removal by two adsorbents, i.e., concrete-containing graphene (CG) and powder-activated carbon (PAC), was investigated via batch-mode experiments and the outcomes were used to analyze the kinetics, equilibrium and thermodynamics of MNZ adsorption. MNZ sorption on CG and PAC has followed the pseudo-second-order kinetic model, and the thermodynamic parameters revealed that MNZ adsorption was spontaneous on PAC and non-spontaneous on CG. Subsequently, two-parameter isotherm models, i.e., Langmuir, Freundlich, Temkin, Dubinin-Radushkevich and Elovich models, were applied to evaluate the MNZ adsorption capacity. The maximum MNZ adsorption capacities ([Formula: see text]) of PAC and CG were found to be between 25.5-32.8 mg/g and 0.41-0.002 mg/g, respectively. Subsequently, the effects of pH, temperature and adsorbent dosage on MNZ adsorption were evaluated by a central composite design (CCD) approach. The CCD experiments have pointed out the complete removal of MNZ at a much lower PAC dosage by increasing the system temperature (i.e., from 20°C to 40°C). On the other hand, a desorption experiment has shown 3.5% and 1.7% MNZ removal from the surface of PAC and CG, respectively, which was insignificant compared to the sorbed MNZ on the surface by adsorption. The overall findings indicate that PAC and CG with higher graphene content could be useful in MNZ removal from aqueous systems.

  16. Material parameter identification on metal matrix composites

    CSIR Research Space (South Africa)

    Jansen van Rensburg, GJ

    2012-07-01

    Full Text Available conditions that best replicate the experimental data. The quality of the fits is subject to the limits of the material model and boundary parameterisation. An alternative procedure that uses the time and strain history to evolve the yield stress is also...

  17. Microgel polymer composite fibres

    OpenAIRE

    Kehren, Dominic

    2014-01-01

    In this thesis some novel ideas and advancements in the field of polymer composite fibres, specifically microgel-based polymer composite fibres have been achieved. The main task was to investigate and understand the electrospinning process of microgels and polymers and the interplay of parameter influences, in order to fabricate reproducible and continuously homogenous composite fibres. The main aim was to fabricate a composite material which combines the special properties of polymer fibres ...

  18. Selection of Compositions in Ti-Cr-C-Steel, Ti-B, Ti-B-Me Systems and Establishing Synthesis Parameters for Obtaining Product by “SHS-Electrical Rolling”

    Science.gov (United States)

    Aslamazashvili, Zurab; Tavadze, Giorgi; Chikhradze, Mikheil; Namicheishvili, Teimuraz; Melashvili, Zaqaria

    2017-12-01

    For the production materials by the proposed Self-propagating High-Temperature Synthesis (SHS) - Electric Rolling method, there are no limitations in the length of the material and the width only depends on the length of rolls. The innovation method enables to carry out the process in nonstop regime, which is possible by merging energy consuming SHS method and Electrical Rolling. For realizing the process it is mandatory and sufficient, that initial components, after initiation by thermal pulse, could interaction with the heat emission, which itself ensures the self-propagation of synthesis front in lieu of heat transfer in the whole sample. Just after that process, the rolls instantly start rotation with the set speed to ensure the motion of material. This speed should be equal to the speed of propagation of synthesis front. The synthesized product in hot plastic condition is delivered to the rolls in nonstop regime, simultaneously, providing the current in deformation zone in order to compensate the energy loses. As a result by using the innovation SHS -Electrical Rolling technology we obtain long dimensional metal-ceramic product. In the presented paper optimal compositions of SHS chasms were selected in Ti-Cr-C-Steel, Ti-B and Ti-B-Me systems. For the selection of the compounds the thermodynamic analysis has been carried out which enabled to determine adiabatic temperature of synthesis theoretically and to determine balanced concentrations of synthesized product at synthesis temperature. Thermodynamic analysis also gave possibility to determine optimal compositions of chasms and define the conditions, which are important for correct realization of synthesis process. For obtaining non porous materials and product by SHS-Electrical Rolling, it is necessary to select synthesis and compacting parameters correctly. These parameters are the pressure and the time. In Ti-Cr-C-Steel, Ti-B and Ti-B-Me systems the high quality (nonporous or low porosity values are defined

  19. Bomb parameters

    International Nuclear Information System (INIS)

    Kerr, George D.; Young, Rebert W.; Cullings, Harry M.; Christry, Robert F.

    2005-01-01

    The reconstruction of neutron and gamma-ray doses at Hiroshima and Nagasaki begins with a determination of the parameters describing the explosion. The calculations of the air transported radiation fields and survivor doses from the Hiroshima and Nagasaki bombs require knowledge of a variety of parameters related to the explosions. These various parameters include the heading of the bomber when the bomb was released, the epicenters of the explosions, the bomb yields, and the tilt of the bombs at time of explosion. The epicenter of a bomb is the explosion point in air that is specified in terms of a burst height and a hypocenter (or the point on the ground directly below the epicenter of the explosion). The current reassessment refines the energy yield and burst height for the Hiroshima bomb, as well as the locations of the Hiroshima and Nagasaki hypocenters on the modern city maps used in the analysis of the activation data for neutrons and TLD data for gamma rays. (J.P.N.)

  20. Process conditions and volumetric composition in composites

    DEFF Research Database (Denmark)

    Madsen, Bo

    2013-01-01

    The obtainable volumetric composition in composites is linked to the gravimetric composition, and it is influenced by the conditions of the manufacturing process. A model for the volumetric composition is presented, where the volume fractions of fibers, matrix and porosity are calculated...... as a function of the fiber weight fraction, and where parameters are included for the composite microstructure, and the fiber assembly compaction behavior. Based on experimental data of composites manufactured with different process conditions, together with model predictions, different types of process related...... effects are analyzed. The applied consolidation pressure is found to have a marked effect on the volumetric composition. A power-law relationship is found to well describe the found relations between the maximum obtainable fiber volume fraction and the consolidation pressure. The degree of fiber...

  1. Effects of exercise and milk fat globule membrane (MFGM supplementation on body composition, physical function, and hematological parameters in community-dwelling frail Japanese women: a randomized double blind, placebo-controlled, follow-up trial.

    Directory of Open Access Journals (Sweden)

    Hunkyung Kim

    Full Text Available To investigate the combined and separate effects of exercise and milk fat globule membrane (MFGM supplementation on frailty, physical function, physical activity level, and hematological parameters in community-dwelling elderly Japanese women.A total of 131 frail, elderly women over 75 years were randomly assigned to one of four groups: exercise and MFGM supplementation (Ex+MFGM, exercise and placebo (Ex+Plac, MFGM supplementation, or the placebo group. The exercise group attended a 60-minute training program twice a week for three months, and the MFGM group ingested 1g of the MFGM supplement in pill form, daily for 3 months. The primary outcome measure was change in frailty status based on Fried's frailty phenotype. Secondary outcome measures included body composition, physical function and hematological parameters, and interview survey components assessing lifestyle factors. Participants were followed for 4 months post-intervention.Significant group × time interactions were observed for usual walking speed (P = 0.005, timed up & go (P<0.001, and insulin-like growth factor-binding protein 3/insulin-like growth factor 1 ratio (P = 0.013. The frailty components revealed that weight loss, exhaustion, low physical activity, and slow walking speed were reversed, but low muscle strength did not significantly changed. Frailty reversal rate was significantly higher in the Ex+MFGM (57.6% than in the MFGM (28.1% or placebo (30.3% groups at post-intervention (χ2 = 8.827, P = 0.032, and at the follow-up was also significantly greater in the Ex+MFGM (45.5% and Ex+Plac (39.4% groups compared with the placebo (15.2% group (χ2 = 8.607, P = 0.035. The exercise+MFGM group had the highest odds ratio (OR for frailty reversal at post-intervention and follow-up (OR = 3.12, 95% confidence interval (CI = 1.13-8.60; and OR = 4.67, 95% CI = 1.45-15.08, respectively.This study suggests that interventions including exercise and nutrition can improve frailty status

  2. Influence of composition on optical and dispersion parameters of thermally evaporated non-crystalline Cd{sub 50}S{sub 50−x}Se{sub x} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Hassanien, A.S., E-mail: a.s.hassanien@gmail.com [Engineering Mathematics and Physics Dept., Faculty of Engineering (Shoubra), Benha University (Egypt); Physics Department, Faculty of Science and Humanities in Ad-Dawadmi, Shaqra University, 11911 (Saudi Arabia); Akl, Alaa A. [Physics Department, Faculty of Science and Humanities in Ad-Dawadmi, Shaqra University, 11911 (Saudi Arabia)

    2015-11-05

    Non-crystalline thin films of chalcogenide Cd{sub 50}S{sub 50−x}Se{sub x} system (30 ≤ x ≤ 50) were obtained by thermal evaporation technique onto a pre-cleaned glass substrate at a vacuum of 8.2 × 10{sup −4} Pa. The deposition rate and film thickness were kept constant at about 8 nm/s and 200 nm, respectively. Amorphous/crystalline nature and chemical composition of films have been checked using X-ray diffraction and energy dispersive X-ray spectroscopy (EDX). Optical properties of thin films were investigated and studied using the corrected transmittance, T(λ) and corrected reflectance, R(λ) measurements. Obtained data reveal that, the indirect optical energy gap (E{sub g}) was decreased from 2.21 to 1.57 eV. On the contrary, Urbach energy (band tail width), E{sub U} was found to be increased from 0.29 to 0.45 eV. This behavior is believed to be associated with the increase of Se-content instead of S-content in the thin films of Cd{sub 50}S{sub 50−x}Se{sub x} system. Chemical bond approach model, CBA was used to analyze the obtained values of E{sub g} and E{sub U}. Optical density, skin depth, extinction coefficient, refractive index and optical conductivity of chalcogenide CdSSe thin films were discussed as functions of Se-content. Using Wemple-DiDomenico single oscillator model, the refractive index dispersion and energy parameters and their dependence on Se content were studied. - Highlights: • Amorphous thin films of thickness 200 nm of Cd{sub 50}S{sub 50−x}Se{sub x} (30 ≤ x ≤ 50) have prepared. • Optical properties, indirect optical energy gap and band tail width were studied. • Chemical bond approach, CBA was used to analyze the obtained values of E{sub g} and E{sub U}. • New data of dispersion refractive index parameters were investigated and discussed.

  3. Physiological parameters

    International Nuclear Information System (INIS)

    Natera, E.S.

    1998-01-01

    The physiological characteristics of man depend on the intake, metabolism and excretion of stable elements from food, water, and air. The physiological behavior of natural radionuclides and radionuclides from nuclear weapons testing and from the utilization of nuclear energy is believed to follow the pattern of stable elements. Hence information on the normal physiological processes occurring in the human body plays an important role in the assessment of the radiation dose received by man. Two important physiological parameters needed for internal dose determination are the pulmonary function and the water balance. In the Coordinated Research Programme on the characterization of Asian population, five participants submitted data on these physiological characteristics - China, India, Japan, Philippines and Viet Nam. During the CRP, data on other pertinent characteristics such as physical and dietary were simultaneously being collected. Hence, the information on the physiological characteristics alone, coming from the five participants were not complete and are probably not sufficient to establish standard values for the Reference Asian Man. Nonetheless, the data collected is a valuable contribution to this research programme

  4. Composite operators in QCD

    International Nuclear Information System (INIS)

    Sonoda, Hidenori

    1992-01-01

    We give a formula for the derivatives of a correlation function of composite operators with respect to the parameters (i.e. the strong fine structure constant and the quark mass) of QCD in four- dimensional euclidean space. The formula is given as spatial integration of the operator conjugate to a parameter. The operator product of a composite operator and a conjugate operator has an unintegrable part, and the formula requires divergent subtractions. By imposing consistency conditions we drive a relation between the anomalous dimensions of the composite operators and the unintegrable part of the operator product coefficients. (orig.)

  5. Influence of bondcoat composition and manufacturing parameters on the lifetime of thermal barrier coatings under cyclic temperature loading; Einfluss der Bondcoatzusammensetzung und Herstellungsparameter auf die Lebensdauer von Waermedaemmschichten bei zyklischer Temperaturbelastung

    Energy Technology Data Exchange (ETDEWEB)

    Subanovic, Marko

    2008-08-21

    In the present study the influence of the bond coat composition on the lifetime of thermal barrier coatings during thermal cycling was investigated. The knowledge, that the reactive elements (RE), which are essential for the improvement of the oxide scale adhesion, are ''lost'', during the bond coat processing, made it necessary to investigate systematically the influence of the different manufacturing stages on the RE distribution. After VPS (vacuum plasma spraying) with a high oxygen partial pressure in the spraying chamber, the reactive elements in the NiCoCrAl-coating were tied up in oxide precipitates, and thus their beneficial effect on the scale adhesion was inhibited. Another important observation is that the RE's are depleted during the bondcoat vacuum heat-treatment. The degree of Y-depletion depends not only on the Y-reservoir in the coating (Y-content and thickness) but also on the heat-treatment parameters, such as vacuum quality and temperature. A thin, dense alumina oxide scale with a smooth interface between bond coat and TGO doesn't necessary lead to a lifetime extension of the EB-PVD TBC's. TBC's with such oxide morphology typically failed due to crack formation and propagation along the interface between the TGO and the bondcoat. By addition of zirconium it was possible to shift the failure initiation from the interface TGO/bondcoat to the interface TBC/TGO, which can apparently accommodate more thermal strain energy before failure. The shift of the failure location was achieved by a change of the oxide morphology, which mainly relies on adjusting a non-even wavy interface between the TGO and the bond coat and formation of defected oxide layers. In contrast, a defected oxide scale with a high growth rate shortened the life time of APSTBC's. Porosity and spinel formation weakened the mechanical integrity of the oxide scale, and facilitated the crack formation and propagation of the already existing

  6. Tuning the nano/micro-structure and properties of melt-processed ternary composites of polypropylene/ethylene vinyl acetate blend and nanoclay: The influence of kinetic and thermodynamic parameters

    CSIR Research Space (South Africa)

    Mofokeng, Tladi G

    2017-09-01

    Full Text Available The present study reports the dependence of the nano/micro-structure and properties of polypropylene (PP)/ethylene vinyl acetate (EVA)/nanoclay ternary composites on the kinetics and thermodynamics of the melt-mixing process. The size of dispersed...

  7. New composite index based on midlatency auditory evoked potential and electroencephalographic parameters to optimize correlation with propofol effect site concentration - Comparison with bispectral index and solitary used fast extracting auditory evoked potential index

    NARCIS (Netherlands)

    Vereecke, HEM; Vasquez, PM; Jensen, EW; Thas, O; Vandenbroecke, R; Mortier, EP; Struys, MMRF

    Background: This study investigates the accuracy of a composite index, the A-Line (R) auditory evoked potentials index version 1.6 (AAI(1.6); Danmeter A/S, Odense, Denmark), as a measure of cerebral anesthetic drug effect in a model for predicting a calculated effect site concentration of propofol

  8. Partially composite Higgs models

    DEFF Research Database (Denmark)

    Alanne, Tommi; Buarque Franzosi, Diogo; Frandsen, Mads T.

    2018-01-01

    We study the phenomenology of partially composite-Higgs models where electroweak symmetry breaking is dynamically induced, and the Higgs is a mixture of a composite and an elementary state. The models considered have explicit realizations in terms of gauge-Yukawa theories with new strongly...... interacting fermions coupled to elementary scalars and allow for a very SM-like Higgs state. We study constraints on their parameter spaces from vacuum stability and perturbativity as well as from LHC results and find that requiring vacuum stability up to the compositeness scale already imposes relevant...... constraints. A small part of parameter space around the classically conformal limit is stable up to the Planck scale. This is however already strongly disfavored by LHC results. in different limits, the models realize both (partially) composite-Higgs and (bosonic) technicolor models and a dynamical extension...

  9. Healable Composites

    Science.gov (United States)

    2012-03-28

    oriented fibers and healable polymer matrix 4. Laminate pre-preg layers to form composite panels with minimal voids & defects 5. Characterize the...composites: determine mechanical and crack healing properties (4, 5) Composite (3) Prepreg (2) Polymer (1) Furan (1) Maleimide Healable Composites...Develop pre-preg system of oriented fibers and healable polymer matrix 4. Laminate pre-preg layers to form composite panels with minimal voids & defects

  10. Experimental Studies of the Effects of Anode Composition and Process Parameters on Anode Slime Adhesion and Cathode Copper Purity by Performing Copper Electrorefining in a Pilot-Scale Cell

    Science.gov (United States)

    Zeng, Weizhi; Wang, Shijie; Free, Michael L.

    2016-10-01

    Copper electrorefining tests were conducted in a pilot-scale cell under commercial tankhouse environment to study the effects of anode compositions, current density, cathode blank width, and flow rate on anode slime behavior and cathode copper purity. Three different types of anodes (high, mid, and low impurity levels) were used in the tests and were analyzed under SEM/EDS. The harvested copper cathodes were weighed and analyzed for impurities concentrations using DC Arc. The adhered slimes and released slimes were collected, weighed, and analyzed for compositions using ICP. It was shown that the lead-to-arsenic ratio in the anodes affects the sintering and coalescence of slime particles. High current density condition can improve anode slime adhesion and cathode purity by intensifying slime particles' coalescence and dissolving part of the particles. Wide cathode blanks can raise the anodic current densities significantly and result in massive release of large slime particle aggregates, which are not likely to contaminate the cathode copper. Low flow rate can cause anode passivation and increase local temperatures in front of the anode, which leads to very intense sintering and coalescence of slime particles. The results and analyses of the tests present potential solutions for industrial copper electrorefining process.

  11. Strength of Fibrous Composites

    CERN Document Server

    Huang, Zheng-Ming

    2012-01-01

    "Strength of Fibrous Composites" addresses evaluation of the strength of a fibrous composite by using its constituent material properties and its fiber architecture parameters. Having gone through the book, a reader is able to predict the progressive failure behavior and ultimate strength of a fibrous laminate subjected to an arbitrary load condition in terms of the constituent fiber and matrix properties, as well as fiber geometric parameters. The book is useful to researchers and engineers working on design and analysis for composite materials. Dr. Zheng-Ming Huang is a professor at the School of Aerospace Engineering & Applied Mechanics, Tongji University, China. Mr. Ye-Xin Zhou is a PhD candidate at the Department of Mechanical Engineering, the University of Hong Kong, China.

  12. Comet Halley, parameter study I

    International Nuclear Information System (INIS)

    Huebner, W.F.; Fikani, M.M.

    1982-06-01

    To aid in defining a mission to comet P/Halley, its inner coma is simulated by a computer program that models time-dependent chemical reactions in a radially and isentropically expanding gas, taking into account attenuation of solar ultraviolet radiation in the subsolar direction. Column density predictions are based on intelligently selected combinations of poorly known values for nucleus parameters that include size, visual albedo, and infrared emissivity. Only one chemical composition and a minor modification of it are considered here; the dust-to-gas ratio in this model is zero. Although the somewhat optimistically volatile composition chosen here favors a smaller nucleus, a mean nuclear radius of only 0.5 km is unlikely. No significant increase of molecular column density is predicted by this model as a spacecraft approaches, once it is less than a few 10 4 km from the nucleus. Predictions are made for various heliocentric distances of interest for comet missions and for ground observations

  13. Booster parameter list

    International Nuclear Information System (INIS)

    Parsa, Z.

    1986-10-01

    The AGS Booster is designed to be an intermediate synchrotron injector for the AGS, capable of accelerating protons from 200 MeV to 1.5 GeV. The parameters listed include beam and operational parameters and lattice parameters, as well as parameters pertaining to the accelerator's magnets, vacuum system, radio frequency acceleration system, and the tunnel. 60 refs., 41 figs

  14. Lumped-parameter models

    Energy Technology Data Exchange (ETDEWEB)

    Ibsen, Lars Bo; Liingaard, M.

    2006-12-15

    A lumped-parameter model represents the frequency dependent soil-structure interaction of a massless foundation placed on or embedded into an unbounded soil domain. In this technical report the steps of establishing a lumped-parameter model are presented. Following sections are included in this report: Static and dynamic formulation, Simple lumped-parameter models and Advanced lumped-parameter models. (au)

  15. New fundamental parameters for attitude representation

    Science.gov (United States)

    Patera, Russell P.

    2017-08-01

    A new attitude parameter set is developed to clarify the geometry of combining finite rotations in a rotational sequence and in combining infinitesimal angular increments generated by angular rate. The resulting parameter set of six Pivot Parameters represents a rotation as a great circle arc on a unit sphere that can be located at any clocking location in the rotation plane. Two rotations are combined by linking their arcs at either of the two intersection points of the respective rotation planes. In a similar fashion, linking rotational increments produced by angular rate is used to derive the associated kinematical equations, which are linear and have no singularities. Included in this paper is the derivation of twelve Pivot Parameter elements that represent all twelve Euler Angle sequences, which enables efficient conversions between Pivot Parameters and any Euler Angle sequence. Applications of this new parameter set include the derivation of quaternions and the quaternion composition rule, as well as, the derivation of the analytical solution to time dependent coning motion. The relationships between Pivot Parameters and traditional parameter sets are included in this work. Pivot Parameters are well suited for a variety of aerospace applications due to their effective composition rule, singularity free kinematic equations, efficient conversion to and from Euler Angle sequences and clarity of their geometrical foundation.

  16. Wood composites

    Science.gov (United States)

    Lars Berglund; Roger M. Rowell

    2005-01-01

    A composite can be defined as two or more elements held together by a matrix. By this definition, what we call “solid wood” is a composite. Solid wood is a three-dimensional composite composed of cellulose, hemicelluloses and lignin (with smaller amounts of inorganics and extractives), held together by a lignin matrix. The advantages of developing wood composites are (...

  17. Little composite dark matter.

    Science.gov (United States)

    Balkin, Reuven; Perez, Gilad; Weiler, Andreas

    2018-01-01

    We examine the dark matter phenomenology of a composite electroweak singlet state. This singlet belongs to the Goldstone sector of a well-motivated extension of the Littlest Higgs with T -parity. A viable parameter space, consistent with the observed dark matter relic abundance as well as with the various collider, electroweak precision and dark matter direct detection experimental constraints is found for this scenario. T -parity implies a rich LHC phenomenology, which forms an interesting interplay between conventional natural SUSY type of signals involving third generation quarks and missing energy, from stop-like particle production and decay, and composite Higgs type of signals involving third generation quarks associated with Higgs and electroweak gauge boson, from vector-like top-partners production and decay. The composite features of the dark matter phenomenology allows the composite singlet to produce the correct relic abundance while interacting weakly with the Higgs via the usual Higgs portal coupling [Formula: see text], thus evading direct detection.

  18. DP: Parameter Display Page Program

    International Nuclear Information System (INIS)

    Anderson, M.

    1994-01-01

    The Parameter Display Page program (DP) is a Motif/X11-based program to allow easily configured, dynamic device and process variable monitoring and manipulation in the EPICS environment. DP provides a tabular data format for interactive viewing and manipulation of device and process variable statistics, as well as formatted PostScript output to files and printers. DP understands and operates in two (unfortunately disjoint at this time) namespaces in the EPICS environment ''devices'' and ''process variables''. The higher level namespace of devices includes Composite and Atomic Devices registered via the Device Access server; the lower level (flat) namespace is that of normal Process Variables accessible via Channel Access

  19. Separation of BSA through FAU-type zeolite ceramic composite membrane formed on tubular ceramic support: Optimization of process parameters by hybrid response surface methodology and biobjective genetic algorithm.

    Science.gov (United States)

    Vinoth Kumar, R; Ganesh Moorthy, I; Pugazhenthi, G

    2017-08-09

    In this study, Faujasite (FAU) zeolite was coated on low-cost tubular ceramic support as a separating layer through hydrothermal route. The mixture of silicate and aluminate solutions was used to create a zeolitic separation layer on the support. The prepared zeolite ceramic composite membrane was characterized using X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), particle size distribution (PSD), field emission scanning electron microscopy (FESEM), and zeta potential measurements. The porosity of ceramic support (53%) was reduced by the deposition of FAU (43%) zeolite layer. The pore size and water permeability of the membrane were evaluated as 0.179 µm and 1.62 × 10 -7  m 3 /m 2  s kPa, respectively, which are lower than that of the support (pore size of 0.309 µm and water permeability of 5.93 × 10 -7  m 3 /m 2  s kPa). The permeate flux and rejection potential of the prepared membrane were evaluated by microfiltration of bovine serum albumin (BSA). To study the influences of three independent variables such as operating pressure (68.94-275.79 kPa), concentration of BSA (100-500 ppm), and solution pH (2-4) on permeate flux and percentage of rejection, the response surface methodology (RSM) was used. The predicted models for permeate flux and rejection were further subjected to biobjective genetic algorithm (GA). The hybrid RSM-GA approach resulted in a maximum permeate flux of 2.66 × 10 -5  m 3 /m 2  s and BSA rejection of 88.02%, at which the optimum conditions were attained as 100 ppm BSA concentration, 2 pH solution, and 275.79 kPa applied pressure. In addition, the separation efficiency was compared with other membranes applied for BSA separation to know the potential of the fabricated FAU zeolite ceramic composite membrane.

  20. Calculation of the fuel composition and the thermo-neutronic parameters of the Bushehr’s VVER-1000 reactor during the initial startup and the first cycle using the WIMSD5-B, CITATION-LDI2 and WERL codes

    International Nuclear Information System (INIS)

    Rahmani, Yashar; Pazirandeh, Ali; Ghofrani, Mohammad B.; Sadighi, Mostafa

    2013-01-01

    Highlights: ► In this paper, the changes of the thermo-neutronic parameters of a VVER 1000 reactor were studied during the first cycle. ► The coupling of neutronic and thermo-hydraulic codes was utilized. ► A computational program (WERL code) was designed to calculate the temperature distribution of the reactor core. ► To estimate the concentration of the released gaseous fission products, the Weisman model was used. ► The results of this study enjoyed the desirable accuracy. - Abstract: In this paper, the concentrations of fission products and fuel isotopes as well as the changes of the thermo-neutronic parameters of the Bushehr’s VVER-1000 reactor were studied during the initial startup and the first cycle. In order to perform the time-dependent cell calculations and obtain the concentration of fuel elements, the WIMSD5-B code was used. Besides, by utilizing the CITATION-LDI2 code, the effective multiplication factor and the thermal power distribution of the reactor were calculated. A computer program (WERL code) was designed in order to perform accurate calculation of the temperature distribution of the reactor core. For this purpose, the Ross–Stoute, Weisman, and Lee–Kesler models were used for calculating of the gap conductance coefficient, fission gas release and gap pressure, respectively. The results demonstrated that in designing the startup process, in addition to the role considered for overcoming the power defects and in preparing the required conditions for performing the safety-assurance tests, the flattening of the reactor’s power must be taken into account. Comparison between the results of this modeling and the final safety analysis report of this reactor showed that the results presented in this paper are satisfactorily accurate

  1. Isoflavones, calcium, vitamin D and inulin improve quality of life, sexual function, body composition and metabolic parameters in menopausal women: result from a prospective, randomized, placebo-controlled, parallel-group study.

    Science.gov (United States)

    Vitale, Salvatore Giovanni; Caruso, Salvatore; Rapisarda, Agnese Maria Chiara; Cianci, Stefano; Cianci, Antonio

    2018-03-01

    Menopause results in metabolic changes that contribute to increase risk of cardiovascular diseases: increase in low density lipoprotein (LDL) and triglycerides and decrease in high density lipoprotein (HDL), weight gain are associated with a correspondent increase in incidence of hypertension and diabetes. The aim of this study was to evaluate the effect of a preparation of isoflavones, calcium vitamin D and inulin in menopausal women. We performed a prospective, randomized, placebo-controlled, parallel-group study. A total of 50 patients were randomized to receive either oral preparations of isoflavones (40 mg), calcium (500 mg) vitamin D (300 UI) and inulin (3 g) or placebo (control group). Pre- and post-treatment assessment of quality of life and sexual function were performed through Menopause-Specific Quality of Life Questionnaire (MENQOL) and Female Sexual Function Index (FSFI); evaluations of anthropometric indicators, body composition through bioelectrical impedance analyser, lumbar spine and proximal femur T-score and lipid profile were performed. After 12 months, a significant reduction in MENQOL vasomotor, physical and sexual domain scores ( p 0.05) were found in the same group. According to our data analysis, isoflavones, calcium, vitamin D and inulin may exert favourable effects on menopausal symptoms and signs.

  2. Study of {sup 4}the influence of annealing parameters on the optical and compositional properties of ZnS, ZnS:Mn and ZnS:Sm grown by Sol Gel

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Barojas, E [CIDS-IC, BUAP. Ed. 103C, C.U. Col. San Manuel. Puebla, Pue. 72570 (Mexico); Sanchez-Mora, E; Silva-Gonzalez, R [Instituto de Fisica, BUAP. Apdo. Postal J-48 Puebla, Pue. 72570 (Mexico); Mendoza-Dorantes, T; Castillo-Abriz, C, E-mail: egomez@sirio.ifuap.buap.m [FIQ, BUAP. Puebla, Pue. 72570 (Mexico)

    2009-05-01

    Samples with 3 layers of ZnS were prepared on glass substrate by the Sol Gel method. The annealing parameters were varied as follows: each of the 3 constituent layers of sample 1 was annealed at 400 deg. C for 12 hrs. For sample 2, the 1rst and 2nd layers were annealed at 300 deg. C for 2hrs each and the 3rd one at 400 deg. C for 12 hrs. For sample 3, the 1st and 2nd layers were annealed at 200 deg. C for 2hrs each and the 3rd at 400 deg. C for 12 hrs. Furthermore, 2 samples: one with 3 layers of ZnS:Mn and the other with 3 layers of ZnS:Sm were prepared and annealed similarly to sample 2. AES depth profiles show a transversal diffusion of S in sample 1, a sulfur deficiency in sample 2, and a non distributed excess of S in sample 3. The absorption spectra of the 3 ZnS samples are very similar but the absorption edges shift to smaller energy values for the Mn and Sm doped ZnS samples. Sample 1 presents a PL spectrum with 2 bands at 441 and 537 nm while sample 2 presents a similar spectrum but the bands are 16 and 11 nm blue shifted.

  3. Produção, composição do leite e constituintes sangüíneos de cabras alimentadas com diferentes volumosos Production, milk composition and blood parameters in goats fed different forages

    Directory of Open Access Journals (Sweden)

    L.R. Ribeiro

    2008-12-01

    Full Text Available Utilizaram-se nove cabras da raça Saanen, para estudar o efeito de dietas compostas por três diferentes fontes de volumosos, feno de alfafa, silagem de milho e feno de aveia, sobre a ingestão de matéria seca, produção e composição do leite e sobre os constituintes sangüíneos, glicose e uréia plasmáticas, em triplo quadrado latino 3x3. Os consumos de matéria seca e proteína bruta dos animais alimentados com feno de alfafa foram mais altos que os à base de silagem de milho (P0,05 das dietas sobre a produção diária de leite (kg/dia, sobre os teores (% de gordura, proteína, lactose e sólidos totais e sobre a contagem de células somáticas (cels/mlx1000. Os animais que consumiram feno de alfafa produziram maiores quantidades (P0,05. Os resultados indicaram que a fonte de volumoso, em rações isoenergéticas e isoproteicas, afeta o desempenho dos animais pela alteração no consumo de MS e PB e produção dos constituintes do leite (kg/dia.Nine Saanen dairy goats, consuming diets composed of three different sources of roughage (alfalfa hay, corn silage, and oat hay were used to study the effect of those diets on the ingestion of dry matter (DM, on milk production, milk composition, and plasmatic glucose and urea levels. The experimental design was a triple latin square 3x3. The intakes of DM and crude protein by the animals fed on alfalfa hay were higher than those fed ration based on corn silage (P0.05 of the diets on the daily milk production and on the fat, protein, lactose, and total solids contents, and on the somatic cells count (SCC, but those cows that received diets with alfalfa hay produced higher amounts (g/day (P0.05. It can be concluded that the forage sources affect the animal performance from changes in both DM and CP intakes and production of milk components (kg/day.

  4. Disorder parameter of confinement

    International Nuclear Information System (INIS)

    Nakamura, N.; Ejiri, S.; Matsubara, Y.; Suzuki, T.

    1996-01-01

    The disorder parameter of confinement-deconfinement phase transition based on the monopole action determined previously in SU(2) QCD are investigated. We construct an operator which corresponds to the order parameter defined in the abelian Higgs model. The operator shows proper behaviors as the disorder parameter in the numerical simulations of finite temperature QCD. (orig.)

  5. Effects of Lactofermented Beetroot Juice Alone or with N-nitroso-N-methylurea on Selected Metabolic Parameters, Composition of the Microbiota Adhering to the Gut Epithelium and Antioxidant Status of Rats.

    Science.gov (United States)

    Klewicka, Elżbieta; Zduńczyk, Zenon; Juśkiewicz, Jerzy; Klewicki, Robert

    2015-07-16

    An objective of this work was to assess the biological activity of beetroot juice (Chrobry variety, Beta vulgaris L. ssp. vulgaris), which was lactofermented by probiotic bacteria Lactobacillus brevis 0944 and Lactobacillus paracasei 0920. The oxidative status of blood serum, kidneys, and liver of rats consuming the fermented beetroot juice were determined. The experimental rats were divided into four groups on diet type: Basal diet, basal diet supplemented with fermented beetroot juice, basal diet and N-nitroso-N-methylurea treatment, and basal diet supplemented with fermented beetroot juice and N-nitroso-N-methylurea treatment. Mutagen N-nitroso-N-methylurea, which was added to diet in order to induce aberrant oxidative and biochemical processes and disadvantageous changes in the count and metabolic activity of the gut epithelium microbiota. The nutritional in vivo study showed that supplementing the diet of the rats with the lactofermented beetroot juice reduced the level of ammonia by 17% in the group treated with N-nitroso-N-methylurea. Furthermore, the positive modulation of the gut microflora and its metabolic activity was observed in groups of rats fed with the diet supplemented with the fermented beetroot juice. A concomitant decrease in the b-glucuronidase activity was a consequence of the gut epithelium microbiota modulation. The antioxidant capacity of blood serum aqueous fraction was increased by about 69% in the group of rats treated N-nitroso-N-methylurea mixed with the fermented beetroot juice and N-nitroso-N-methylurea versus to the N-nitroso-N-methylurea treatment, whereas the antioxidant parameters of the blood serum lipid fraction, kidneys, and liver remained unchanged.

  6. A composite material based on recycled tires

    Science.gov (United States)

    Malers, L.; Plesuma, R.; Locmele, L.

    2009-01-01

    The present study is devoted to the elaboration and investigation of a composite material based on mechanically grinded recycled tires and a polymer binder. The correlation between the content of the binder, some technological parameters, and material properties of the composite was clarified. The apparent density, the compressive stress at a 10% strain, the compressive elastic modulus in static and cyclic loadings, and the insulating properties (acoustic and thermal) were the parameters of special interest of the present investigation. It is found that a purposeful variation of material composition and some technological parameters leads to multifunctional composite materials with different and predictable mechanical and insulation properties.

  7. Composite Materials

    DEFF Research Database (Denmark)

    Nielsen, Lauge Fuglsang

    This book deals with the mechanical and physical behavior of composites as influenced by composite geometry. "Composite Materials" provides a comprehensive introduction for researchers and students to modern composite materials research with a special emphasis on the significance of phase geometry......, viscoelastic behavior, and internal stress states. Other physical properties considered are thermal and electrical conductivities, diffusion coefficients, dielectric constants and magnetic permeability. Special attention is given to the effect of pore shape on the mechanical and physical behavior of porous....... The book enables the reader to a better understanding of the behavior of natural composites, improvement of such materials, and design of new materials with prescribed properties. A number of examples are presented: Special composite properties considered are stiffness, shrinkage, hygro-thermal behavior...

  8. Delamination tolerance studies in laminated composite panels

    Indian Academy of Sciences (India)

    Abstract. Determination of levels of tolerance in delaminated composite panels is an important issue in composite structures technology. The primary intention is to analyse delaminated composite panels and estimate Strain. Energy Release Rate (SERR) parameters at the delamination front to feed into acceptability criteria.

  9. Thermodynamic parameters of elasticity and electrical conductivity ...

    African Journals Online (AJOL)

    The thermodynamic parameters (change in free energy of elasticity, DGe; change in enthalpy of elasticity, DHe; and change in entropy of elasticity, DSe) and the electrical conductivity of natural rubber composites reinforced separately with some agricultural wastes have been determined. Results show that the reinforced ...

  10. Correlation between Composition and Properties of Composite Material Based on Scrap Tires

    OpenAIRE

    Mālers, L; Plēsuma, R; Ločmele, L; Kalniņš, M

    2010-01-01

    Purpose of present work is to investigate mechanical and insulation properties of the composite material based on scrap tires and polyurethane-type binder in correlation with composition of composite material. The studies of material’s hardness must be considered as an express-method for estimation of the selected mechanical properties (E and ccompressive stress) of the composite material without direct experimental testing of given parameters. It was shown that composite material must be r...

  11. Composite gravity and composite supergravity

    International Nuclear Information System (INIS)

    Lukierski, J.

    1982-09-01

    It is known that the composite YM H-gauge theory can be constructed from σ-fields taking values in a symmetric Riemannian space G/H. We extend such a framework to graded σ-fields taking values in supercosets. We show that from supercoset σ-fields one can construct composite gravity, and from supercoset σ-superfields the composite supergravity models. (author)

  12. Composite Territories

    DEFF Research Database (Denmark)

    Nicholas, Paul; Tamke, Martin

    2012-01-01

    and assembly of the fibre reinforced composite structure Composite Territories, in which the property of bending is activated and varied so as to match solely through material means a desired form. This case study demonstrates how one might extend the geometric model so that it is able to engage and reconcile...

  13. Composite Dark Sectors

    International Nuclear Information System (INIS)

    Carmona, Adrian

    2015-06-01

    We introduce a new paradigm in Composite Dark Sectors, where the full Standard Model (including the Higgs boson) is extended with a strongly-interacting composite sector with global symmetry group G spontaneously broken to H is contained in G. We show that, under well-motivated conditions, the lightest neutral pseudo Nambu-Goldstone bosons are natural dark matter candidates for they are protected by a parity symmetry not even broken in the electroweak phase. These models are characterized by only two free parameters, namely the typical coupling g D and the scale f D of the composite sector, and are therefore very predictive. We consider in detail two minimal scenarios, SU(3)/[SU(2) x U(1)] and [SU(2) 2 x U(1)]/[SU(2) x U(1)], which provide a dynamical realization of the Inert Doublet and Triplet models, respectively. We show that the radiatively-induced potential can be computed in a five-dimensional description with modified boundary conditions with respect to Composite Higgs models. Finally, the dark matter candidates are shown to be compatible, in a large region of the parameter space, with current bounds from dark matter searches as well as electroweak and collider constraints on new resonances.

  14. Cosmological Parameters 2000

    OpenAIRE

    Primack, Joel R.

    2000-01-01

    The cosmological parameters that I emphasize are the age of the universe $t_0$, the Hubble parameter $H_0 \\equiv 100 h$ km s$^{-1}$ Mpc$^{-1}$, the average matter density $\\Omega_m$, the baryonic matter density $\\Omega_b$, the neutrino density $\\Omega_\

  15. Computational composites

    DEFF Research Database (Denmark)

    Vallgårda, Anna K. A.; Redström, Johan

    2007-01-01

    Computational composite is introduced as a new type of composite material. Arguing that this is not just a metaphorical maneuver, we provide an analysis of computational technology as material in design, which shows how computers share important characteristics with other materials used in design...... and architecture. We argue that the notion of computational composites provides a precise understanding of the computer as material, and of how computations need to be combined with other materials to come to expression as material. Besides working as an analysis of computers from a designer’s point of view......, the notion of computational composites may also provide a link for computer science and human-computer interaction to an increasingly rapid development and use of new materials in design and architecture....

  16. Hybrid composites

    CSIR Research Space (South Africa)

    Jacob John, Maya

    2009-04-01

    Full Text Available mixed short sisal/glass hybrid fibre reinforced low density polyethylene composites was investigated by Kalaprasad et al [25].Chemical surface modifications such as alkali, acetic anhydride, stearic acid, permanganate, maleic anhydride, silane...

  17. Magnetic S-parameter

    DEFF Research Database (Denmark)

    Sannino, Francesco

    2010-01-01

    We propose a direct test of the existence of gauge duals for nonsupersymmetric asymptotically free gauge theories developing an infrared fixed point by computing the S-parameter in the electric and dual magnetic description. In particular we show that at the lower bound of the conformal window...... the magnetic S-parameter, i.e. the one determined via the dual magnetic gauge theory, assumes a simple expression in terms of the elementary magnetic degrees of freedom. The results further support our recent conjecture of the existence of a universal lower bound on the S parameter and indicates...

  18. Anthropometric and body composition parameters of Kaduna and ...

    African Journals Online (AJOL)

    Journal of Experimental and Clinical Anatomy ... Data obtained showed that limb circumferences of Kaduna women are signifi cantly higher than Rivers women (P < 0.000 for arm circumference, P < 0.01 for calf circumference, and P < 0.000 for forearm circumference) except for the thigh circumference. However, weight ...

  19. Nutrimental Composition and physicochemical parameters of thermosonicated soursop Nectar

    OpenAIRE

    Luis M. Anaya-Esparza; María D. Méndez-Robles; Alejandro Pérez-Larios; Elhadi M. Yahia; Efigenia Montalvo-González

    2018-01-01

    Se evaluó el efecto de la termosonicación (TS) a dos diferentes condiciones experimentales [TS1 = 24 kHz, 1,3 W/mL de densidad de energía acústica (AED), 51 °C durante 8 min y TS2 = 24 kHz, 1,4 W/mL AED, 54 °C durante 10min] sobre la composición nutrimental y parámetros fisicoquímicos de néctar de guanábana almacenado a 4ºC.Como testigos se emplearon un néctar sin tratar y otro pasteurizado tradicionalmente (65 °C, 30 min). La TS nocausó cambios en la mayoría de nutrientes y parámetros fisico...

  20. Effect of process parameters on coating composition of cathodic ...

    Indian Academy of Sciences (India)

    10

    comprising of carbon nanostructure and copper oxide are formed on the copper. ... can lead to the growth of oxide film and be named micro arc oxidation (MAO) ...... A. Yerokhin, X. Li, H. Dong, and A. Matthews, Surface characterisation of DC.

  1. Sorption of radiocesium by composites of variable composition

    International Nuclear Information System (INIS)

    Someda, H.H.; El-zahhar, A.A.; Shehata, M.K.K.; El-Naggar, H.A.

    2000-01-01

    Cellulose and different natural materials - supported hexacyanoferrate composites were prepared and characterized by IR and x-ray diffraction studies. The stability of the prepared composites towards concentrated mineral acids was studied. The capacity of such prepared composites towards the uptake of cesium was calculated and found to be 1.5-1.7 meq/g. The capacity of the natural materials - supported composites was found to be slightly higher than that of the cellulose supported one. Different parameters affecting the sorption process of the radioelement such as acid concentration, Ph variation, competing ions and carrier concentration were studied. The release of the cesium traces from the composite materials was studied under different HCl concentrations and it was found that there is no release of the absorbed cesium up to 2.5 M even for long contact time up to two weeks. The work is under developing and extension

  2. SATELLITE CONSTELLATION DESIGN PARAMETER

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. SATELLITE CONSTELLATION DESIGN PARAMETER. 1. ORBIT CHARACTERISTICS. ORBITAL HEIGHT >= 20,000 KM. LONGER VISIBILITY; ORBITAL PERIOD. PERTURBATIONS(MINIMUM). SOLAR RADIATION PRESSURE (IMPACTS ECCENTRICITY); LUNI ...

  3. Reassessment of safeguards parameters

    Energy Technology Data Exchange (ETDEWEB)

    Hakkila, E.A.; Richter, J.L.; Mullen, M.F.

    1994-07-01

    The International Atomic Energy Agency is reassessing the timeliness and goal quantity parameters that are used in defining safeguards approaches. This study reviews technology developments since the parameters were established in the 1970s and concludes that there is no reason to relax goal quantity or conversion time for reactor-grade plutonium relative to weapons-grade plutonium. For low-enriched uranium, especially in countries with advanced enrichment capability there may be an incentive to shorten the detection time.

  4. Safeguards systems parameters

    International Nuclear Information System (INIS)

    Avenhaus, R.; Heil, J.

    1979-01-01

    In this paper analyses are made of the values of those parameters that characterize the present safeguards system that is applied to a national fuel cycle; those values have to be fixed quantitatively so that all actions of the safeguards authority are specified precisely. The analysis starts by introducing three categories of quantities: The design parameters (number of MBAs, inventory frequency, variance of MUF, verification effort and false-alarm probability) describe those quantities whose values have to be specified before the safeguards system can be implemented. The performance criteria (probability of detection, expected detection time, goal quantity) measure the effectiveness of a safeguards system; and the standards (threshold amount and critical time) characterize the magnitude of the proliferation problem. The means by which the values of the individual design parameters can be determined with the help of the performance criteria; which qualitative arguments can narrow down the arbitrariness of the choice of values of the remaining parameters; and which parameter values have to be fixed more or less arbitrarily, are investigated. As a result of these considerations, which include the optimal allocation of a given inspection effort, the problem of analysing the structure of the safeguards system is reduced to an evaluation of the interplay of only a few parameters, essentially the quality of the measurement system (variance of MUF), verification effort, false-alarm probability, goal quantity and probability of detection

  5. Wear of polymers and composites

    CERN Document Server

    Abdelbary, Ahmed

    2015-01-01

    In the field of tribology, the wear behaviour of polymers and composite materials is considered a highly non-linear phenomenon. Wear of Polymers and Composites introduces fundamentals of polymers and composites tribology. The book suggests a new approach to explore the effect of applied load and surface defects on the fatigue wear behaviour of polymers, using a new tribometer and thorough experiments. It discusses effects of surface cracks, under different static and cyclic loading parameters on wear, and presents an intelligent algorithm, in the form of a neural network, to map the relations

  6. Resin composites

    DEFF Research Database (Denmark)

    Benetti, Ana Raquel; Peutzfeldt, Anne; Lussi, Adrian

    2014-01-01

    OBJECTIVE: To investigate how the modulus of elasticity of resin composites influences marginal quality in restorations submitted to thermocyclic and mechanical loading. METHODS: Charisma, Filtek Supreme XTE and Grandio were selected as they were found to possess different moduli of elasticity...... of resin composite (p=0.81) on the quality of dentine margins was observed, before or after loading. Deterioration of all margins was evident after loading (p....008). CONCLUSIONS: The resin composite with the highest modulus of elasticity resulted in the highest number of gap-free enamel margins but with an increased incidence of paramarginal enamel fractures. CLINICAL SIGNIFICANCE: The results from this study suggest that the marginal quality of restorations can...

  7. Composite Territories

    DEFF Research Database (Denmark)

    Nicholas, Paul; Tamke, Martin

    2012-01-01

    for the varied composition of material, an extension of the digital chain that foregrounds a new need to engage materials at multiple scales within the design process. Recognising that the process of making materials affords perspectives not available with found materials, this paper reports the design...... and assembly of the fibre reinforced composite structure Composite Territories, in which the property of bending is activated and varied so as to match solely through material means a desired form. This case study demonstrates how one might extend the geometric model so that it is able to engage and reconcile......Today, material performance is regarded as one of the richest sources of innovation. Accordingly, architecture is shifting to practices by which the computational generation of form is directly driven by material characteristics. At the same time, there is a growing technological means...

  8. Composite material

    Science.gov (United States)

    Hutchens, Stacy A [Knoxville, TN; Woodward, Jonathan [Solihull, GB; Evans, Barbara R [Oak Ridge, TN; O'Neill, Hugh M [Knoxville, TN

    2012-02-07

    A composite biocompatible hydrogel material includes a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa. A calcium comprising salt is disposed in at least some of the pores. The porous polymer matrix can comprise cellulose, including bacterial cellulose. The composite can be used as a bone graft material. A method of tissue repair within the body of animals includes the steps of providing a composite biocompatible hydrogel material including a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa, and inserting the hydrogel material into cartilage or bone tissue of an animal, wherein the hydrogel material supports cell colonization in vitro for autologous cell seeding.

  9. Computational Composites

    DEFF Research Database (Denmark)

    Vallgårda, Anna K. A.

    to understand the computer as a material like any other material we would use for design, like wood, aluminum, or plastic. That as soon as the computer forms a composition with other materials it becomes just as approachable and inspiring as other smart materials. I present a series of investigations of what...... Computational Composite, and Telltale). Through the investigations, I show how the computer can be understood as a material and how it partakes in a new strand of materials whose expressions come to be in context. I uncover some of their essential material properties and potential expressions. I develop a way...

  10. Monitoring of dabigatran anticoagulation and its reversal in vitro by thrombelastography

    DEFF Research Database (Denmark)

    Solbeck, Sacha; Meyer, Martin A S; Johansson, Pär I

    2014-01-01

    BACKGROUND: Dabigatran etexilate, a pro-drug of a direct thrombin inhibitor, was approved a few years ago for non-valvular atrial fibrillation and deep venous thrombosis. Rapid monitoring of the dabigatran level is essential in trauma and bleeding patients but the traditional plasma-based assays ...

  11. Thrombelastography (TEG) or thromboelastometry (ROTEM) to monitor haemotherapy versus usual care in patients with massive transfusion

    DEFF Research Database (Denmark)

    Afshari, Arash; Wikkelsø, Anne; Brok, Jesper Sune

    2011-01-01

    Severe bleeding and coagulopathy as a result of massive transfusion are serious clinical conditions that are associated with high mortality. Thromboelastography (TEG) and thromboelastometry (ROTEM) are increasingly used to guide transfusion strategy but their roles remain disputed....

  12. Little composite dark matter

    Science.gov (United States)

    Balkin, Reuven; Perez, Gilad; Weiler, Andreas

    2018-02-01

    We examine the dark matter phenomenology of a composite electroweak singlet state. This singlet belongs to the Goldstone sector of a well-motivated extension of the Littlest Higgs with T-parity. A viable parameter space, consistent with the observed dark matter relic abundance as well as with the various collider, electroweak precision and dark matter direct detection experimental constraints is found for this scenario. T-parity implies a rich LHC phenomenology, which forms an interesting interplay between conventional natural SUSY type of signals involving third generation quarks and missing energy, from stop-like particle production and decay, and composite Higgs type of signals involving third generation quarks associated with Higgs and electroweak gauge boson, from vector-like top-partners production and decay. The composite features of the dark matter phenomenology allows the composite singlet to produce the correct relic abundance while interacting weakly with the Higgs via the usual Higgs portal coupling λ _{ {DM}}˜ O(1%), thus evading direct detection.

  13. Little composite dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Balkin, Reuven; Weiler, Andreas [Technische Universitaet Muenchen, First Physik-Department, Garching (Germany); Perez, Gilad [Weizmann Institute of Science, Department of Particle Physics and Astrophysics, Rehovot (Israel)

    2018-02-15

    We examine the dark matter phenomenology of a composite electroweak singlet state. This singlet belongs to the Goldstone sector of a well-motivated extension of the Littlest Higgs with T-parity. A viable parameter space, consistent with the observed dark matter relic abundance as well as with the various collider, electroweak precision and dark matter direct detection experimental constraints is found for this scenario. T-parity implies a rich LHC phenomenology, which forms an interesting interplay between conventional natural SUSY type of signals involving third generation quarks and missing energy, from stop-like particle production and decay, and composite Higgs type of signals involving third generation quarks associated with Higgs and electroweak gauge boson, from vector-like top-partners production and decay. The composite features of the dark matter phenomenology allows the composite singlet to produce the correct relic abundance while interacting weakly with the Higgs via the usual Higgs portal coupling λ{sub DM} ∝ O(1%), thus evading direct detection. (orig.)

  14. Electroweak interaction parameters

    International Nuclear Information System (INIS)

    Marciano, W.J.

    1984-01-01

    After a presentation of the experimentally determined parameters of the standard SU(3) x SU(2) x U(1) model the author discusses the definition of the Weinberg angle. Then masses and widths of the intermediate vector bosons are considered in the framework of the Weinberg-Salam theory with radiative corrections. Furthermore the radiative decays of these bosons are discussed. Then the relations between the masses of the Higgs boson and the top quark are considered. Thereafter grand unification is briefly discussed with special regards to the SU(5) prediction of some observable parameters. Finally some speculations are made concerning the observation of radiative decays in the UA1 experiments. (HSI)

  15. Band parameters of phosphorene

    International Nuclear Information System (INIS)

    Lew Yan Voon, L C; Wang, J; Zhang, Y; Willatzen, M

    2015-01-01

    Phosphorene is a two-dimensional nanomaterial with a direct band-gap at the Brillouin zone center. In this paper, we present a recently derived effective-mass theory of the band structure in the presence of strain and electric field, based upon group theory. Band parameters for this theory are computed using a first-principles theory based upon the generalized-gradient approximation to the density-functional theory. These parameters and Hamiltonian will be useful for modeling physical properties of phosphorene. (paper)

  16. Band parameters of phosphorene

    DEFF Research Database (Denmark)

    Lew Yan Voon, L. C.; Wang, J.; Zhang, Y.

    2015-01-01

    Phosphorene is a two-dimensional nanomaterial with a direct band-gap at the Brillouin zone center. In this paper, we present a recently derived effective-mass theory of the band structure in the presence of strain and electric field, based upon group theory. Band parameters for this theory...... are computed using a first-principles theory based upon the generalized-gradient approximation to the density-functional theory. These parameters and Hamiltonian will be useful for modeling physical properties of phosphorene....

  17. Animal factors affecting fatty acid composition of cow milk fat: A review

    African Journals Online (AJOL)

    , cow individuality, parity and stage of lactation) on fatty acid (FA) composition of milk fat. Genetic parameters affecting the composition of the FAs in milk are reviewed and the possibilities for altering milk fat composition are discussed.

  18. Compositional translation

    NARCIS (Netherlands)

    Appelo, Lisette; Janssen, Theo; Jong, de F.M.G.; Landsbergen, S.P.J.

    1994-01-01

    This book provides an in-depth review of machine translation by discussing in detail a particular method, called compositional translation, and a particular system, Rosetta, which is based on this method. The Rosetta project is a unique combination of fundamental research and large-scale

  19. Composing compositions

    Energy Technology Data Exchange (ETDEWEB)

    DeBoodt, M. F. L. P.; Verdonck, O. F.

    1985-01-22

    A process is disclosed for producing compost and composting compositions having a high nitrogen content and being particularly advantageous for use as fertilizers, said process utilizing petroleum sludge and an organic biomass which preferably contains wood industry residue and organic waste products.

  20. Correlation between birth weight and maternal body composition.

    LENUS (Irish Health Repository)

    Kent, Etaoin

    2013-01-01

    To estimate which maternal body composition parameters measured using multifrequency segmental bioelectric impedance analysis in the first trimester of pregnancy are predictors of increased birth weight.

  1. Flexural vibrations of finite composite poroelastic cylinders

    Indian Academy of Sciences (India)

    We know from daily experience that many man-made structures consist of ..... The physical parameters of these composite cylinders following Eq. (38) are given in ... Titanium implants remain virtually unchanged in appearance, which offers ...

  2. NUTRIENT COMPOSITION OF NIGER SEED (GUIZOTIA ...

    African Journals Online (AJOL)

    B. S. Chandravanshi

    fiber. Niger oil has a fatty acid composition typical for seed oils of the .... system using external calibration curve after optimizing the parameters in to .... physical and chemical properties of the soil, application of natural (manure) and artificial.

  3. Modelling anisotropic water transport in polymer composite ...

    Indian Academy of Sciences (India)

    Parameters for Fickian diffusion and polymer relaxation models were determined by .... Water transport process of resin and polymer composite specimens at ..... simulation. ... Kwon Y W and Bang H 1997 Finite element method using matlab.

  4. Plant fibre composites - porosity and stiffness

    DEFF Research Database (Denmark)

    Madsen, Bo; Thygesen, Anders; Lilholt, Hans

    2009-01-01

    Plant fibre composites contain typically a relatively large amount of porosity which influences their performance. A model, based on a modified rule of mixtures, is presented to include the influence of porosity on the composite stiffness. The model integrates the volumetric composition...... of the composites with their mechanical properties. The fibre weight fraction is used as an independent parameter to calculate the complete volumetric composition. A maximum obtainable stiffness of the composites is calculated at a certain transition fibre weight fraction, which is characterised by a best possible...... combination of high fibre volume fraction and low porosity. The model is validated with experimental data from the literature on several types of composites. A stiffness diagram is presented to demonstrate that the calculations can be used for tailoring and design of composites with a given profile...

  5. Dynamic Analysis of Composite Rotors

    Directory of Open Access Journals (Sweden)

    S. P. Singh

    1996-01-01

    accounted for. Material damping is also taken into account. The layerwise theory is compared with conventionally used equivalent modulus beam theory. Some interesting case studies are presented. The effect of various parameters on dynamic behavior and stability of a composite rotor is presented.

  6. Sea surface stability parameters

    International Nuclear Information System (INIS)

    Weber, A.H.; Suich, J.E.

    1978-01-01

    A number of studies dealing with climatology of the Northwest Atlantic Ocean have been published in the last ten years. These published studies have dealt with directly measured meteorological parameters, e.g., wind speed, temperature, etc. This information has been useful because of the increased focus on the near coastal zone where man's activities are increasing in magnitude and scope, e.g., offshore power plants, petroleum production, and the subsequent environmental impacts of these activities. Atmospheric transport of passive or nonpassive material is significantly influenced by the turbulence structure of the atmosphere in the region of the atmosphere-ocean interface. This research entails identification of the suitability of standard atmospheric stability parameters which can be used to determine turbulence structure; the calculation of these parameters for the near-shore and continental shelf regions of the U.S. east coast from Cape Hatteras to Miami, Florida; and the preparation of a climatology of these parameters. In addition, a climatology for average surface stress for the same geographical region is being prepared

  7. Measuring the chargino parameters

    Indian Academy of Sciences (India)

    by measuring the cross-sections with polarized beams at e+e- collider ... is given by the fundamental SUSY parameters: the SU(2) gaugino mass Е¾, the higgsino .... two points in the plane which are symmetric under the interchange ¾Д ° ¾К.

  8. General image acquisition parameters

    International Nuclear Information System (INIS)

    Teissier, J.M.; Lopez, F.M.; Langevin, J.F.

    1993-01-01

    The general parameters are of primordial importance to achieve image quality in terms of spatial resolution and contrast. They also play a role in the acquisition time for each sequence. We describe them separately, before associating them in a decision tree gathering the various options that are possible for diagnosis

  9. Quantization of physical parameters

    International Nuclear Information System (INIS)

    Jackiw, R.; Massachusetts Inst. of Tech., Cambridge; Massachusetts Inst. of Tech., Cambridge

    1984-01-01

    Dynamical models are described with parameters (mass, coupling strengths) which must be quantized for quantum mechanical consistency. These and related topological ideas have physical application to phenomenological descriptions of high temperature and low energy quantum chromodynamics, to the nonrelativistic dynamics of magnetic monopoles, and to the quantum Hall effect. (author)

  10. Stellar Parameters for Trappist-1

    Science.gov (United States)

    Van Grootel, Valérie; Fernandes, Catarina S.; Gillon, Michael; Jehin, Emmanuel; Manfroid, Jean; Scuflaire, Richard; Burgasser, Adam J.; Barkaoui, Khalid; Benkhaldoun, Zouhair; Burdanov, Artem; Delrez, Laetitia; Demory, Brice-Olivier; de Wit, Julien; Queloz, Didier; Triaud, Amaury H. M. J.

    2018-01-01

    TRAPPIST-1 is an ultracool dwarf star transited by seven Earth-sized planets, for which thorough characterization of atmospheric properties, surface conditions encompassing habitability, and internal compositions is possible with current and next-generation telescopes. Accurate modeling of the star is essential to achieve this goal. We aim to obtain updated stellar parameters for TRAPPIST-1 based on new measurements and evolutionary models, compared to those used in discovery studies. We present a new measurement for the parallax of TRAPPIST-1, 82.4 ± 0.8 mas, based on 188 epochs of observations with the TRAPPIST and Liverpool Telescopes from 2013 to 2016. This revised parallax yields an updated luminosity of {L}* =(5.22+/- 0.19)× {10}-4 {L}ȯ , which is very close to the previous estimate but almost two times more precise. We next present an updated estimate for TRAPPIST-1 stellar mass, based on two approaches: mass from stellar evolution modeling, and empirical mass derived from dynamical masses of equivalently classified ultracool dwarfs in astrometric binaries. We combine them using a Monte-Carlo approach to derive a semi-empirical estimate for the mass of TRAPPIST-1. We also derive estimate for the radius by combining this mass with stellar density inferred from transits, as well as an estimate for the effective temperature from our revised luminosity and radius. Our final results are {M}* =0.089+/- 0.006 {M}ȯ , {R}* =0.121+/- 0.003 {R}ȯ , and {T}{eff} = 2516 ± 41 K. Considering the degree to which the TRAPPIST-1 system will be scrutinized in coming years, these revised and more precise stellar parameters should be considered when assessing the properties of TRAPPIST-1 planets.

  11. Study of a classical strobe composition

    NARCIS (Netherlands)

    Corbel, J.M.L.; Lingen, J.N.J. van; Zevenbergen, J.F.; Gijzeman, O.L.J.; Meijerink, A.

    2013-01-01

    Many strobe compositions were discovered in the past but only a few have been studied and none of them were fully understood. This article aimed at introducing the ternary composition of ammonium perchlorate as oxidizer, magnalium as fuel, and barium sulfate as metal salt. Parameters that influence

  12. Modelling anisotropic water transport in polymer composite

    Indian Academy of Sciences (India)

    This work reports anisotropic water transport in a polymer composite consisting of an epoxy matrix reinforced with aligned triangular bars made of vinyl ester. By gravimetric experiments, water diffusion in resin and polymer composites were characterized. Parameters for Fickian diffusion and polymer relaxation models were ...

  13. Composite thermocouples

    International Nuclear Information System (INIS)

    Debeir, R.P.

    1975-01-01

    As a rule, a composite thermocouple is a thermocouple where one or more components (wires, sheath, insulation) differ in kind between the hot junction measurement point and the cold termination with ordinary cables going on to measurement instrumentation. Three categories of such thermocouples are discussed: composite thermocouples having in common the continuity of the thermoelement wires over complete length, and different sheaths and insulation for the high temperature and intermediate temperature parts; those with different thermoelement wires, sheaths, and insulators for the high and intermediate temperature parts; a third category includes the high temperature thermoelements insulated by Al 2 O 3 or BeO and sheathed with a refractory metal, and with the intermediate temperature part made of 2Cr-Al couples, MgO insulated, and stainless steel or inconel sheathed

  14. Explosive compositions

    Energy Technology Data Exchange (ETDEWEB)

    1971-04-01

    An explosive composition containing ammonium nitrate consists of (1) from 40 to 75 Pt. by wt of particulate ammonium nitrate, (2) from 20 to 35 Pt. by wt of a solution selected from the group consisting of aqueous magnesium nitrate, aqueous ammonium nitrate and aqueous ammoniacal ammonium nitrate; and (3) at least 2 Pt. by wt of a setting agent selected from the group consisting of alkaline earth metal oxides, zinc oxide, lead monoxide, calcined dolomitic limestone, anhydrous calcium sulfate, anhydrous magnesium sulfate, anhydrous sodium tetrapyrophosphate and anhydrous sodium thiosulfate. The setting agent is further characterized in setting the composition to a solid material which contains solvent used in the liquid phase. (Abstract only - original article not available from T.U.)

  15. Explosive composition

    Energy Technology Data Exchange (ETDEWEB)

    Slykhouse, T E

    1968-05-09

    An ammonium nitrate explosive composition is characterized in that it contains from 40 to 75 parts by wt of particulate ammonium nitrate, from 20 to 35 parts by wt of a solution selected from the group consisting of aqueous magnesium nitrate, aqueous ammonium nitrate, and aqueous ammoniacal ammonium nitrate. It also contains at least 2 parts by wt of a setting agent selected from the group consisting of alkaline earth metal oxides, zinc oxide, lead monoxide, calcined dolomitic limestone, substantially anhydrous calcium sulfate, substantially anhydrous magnesium sulfate, substantially anhydrous sodium tetrapyrophosphate and substantially anhydrous sodium thiosulfate. The setting agent is further characterized in that it sets the composition to a solid material which contains solvent used in the liquid phase. (12 claims)

  16. Optomechanical parameter estimation

    International Nuclear Information System (INIS)

    Ang, Shan Zheng; Tsang, Mankei; Harris, Glen I; Bowen, Warwick P

    2013-01-01

    We propose a statistical framework for the problem of parameter estimation from a noisy optomechanical system. The Cramér–Rao lower bound on the estimation errors in the long-time limit is derived and compared with the errors of radiometer and expectation–maximization (EM) algorithms in the estimation of the force noise power. When applied to experimental data, the EM estimator is found to have the lowest error and follow the Cramér–Rao bound most closely. Our analytic results are envisioned to be valuable to optomechanical experiment design, while the EM algorithm, with its ability to estimate most of the system parameters, is envisioned to be useful for optomechanical sensing, atomic magnetometry and fundamental tests of quantum mechanics. (paper)

  17. Critical parameters for ammonia

    International Nuclear Information System (INIS)

    Sato, M.; Masui, G.; Uematsu, M.

    2005-01-01

    (p, ρ, T) measurements and visual observations of the meniscus for ammonia were carried out carefully in the critical region over the range of temperatures: -1 K (T - T c ) 0.04 K, and of densities: -19 kg . m -3 (ρ - ρ c ) 19 kg . m -3 by a metal-bellows volumometer with an optical cell. Vapor pressures were also measured at T = (310, 350, and 400) K. The critical parameters of T c and ρ c were determined based on the results of observation of the critical opalescence. The critical pressure p c was determined from the present measurements at T c on the vapor pressure curve. Comparisons of the critical parameters with values given in the literature are presented

  18. Critical parameters for ammonia

    Energy Technology Data Exchange (ETDEWEB)

    Sato, M. [Center for Mechanical Engineering and Applied Mechanics, Keio University, Hiyoshi 3-14-1, Kohoku-ku, Yokohama 223-8522 (Japan); Masui, G. [Center for Mechanical Engineering and Applied Mechanics, Keio University, Hiyoshi 3-14-1, Kohoku-ku, Yokohama 223-8522 (Japan); Uematsu, M. [Center for Mechanical Engineering and Applied Mechanics, Keio University, Hiyoshi 3-14-1, Kohoku-ku, Yokohama 223-8522 (Japan)]. E-mail: uematsu@mech.keio.ac.jp

    2005-09-15

    (p, {rho}, T) measurements and visual observations of the meniscus for ammonia were carried out carefully in the critical region over the range of temperatures: -1 K (T - T {sub c}) 0.04 K, and of densities: -19 kg . m{sup -3} ({rho} - {rho} {sub c}) 19 kg . m{sup -3} by a metal-bellows volumometer with an optical cell. Vapor pressures were also measured at T = (310, 350, and 400) K. The critical parameters of T {sub c} and {rho} {sub c} were determined based on the results of observation of the critical opalescence. The critical pressure p {sub c} was determined from the present measurements at T {sub c} on the vapor pressure curve. Comparisons of the critical parameters with values given in the literature are presented.

  19. LMFBR plant parameters

    International Nuclear Information System (INIS)

    1979-03-01

    This document contains up-to-date data on existing or firmly decided prototype or demonstration LMFBR reactors (Table I), on planned commercial size LMFBR according to the present status of design (Table II) and on experimental fast reactors such as BOR-60, DFR, EBR-II, FERMI, FFTF, JOYO, KNK-II, PEC, RAPSODIE-FORTISSIMO (Table III). Only corrected and revised parameters submitted by the countries participating in the IWGFR are included in this document

  20. Ranking as parameter estimation

    Czech Academy of Sciences Publication Activity Database

    Kárný, Miroslav; Guy, Tatiana Valentine

    2009-01-01

    Roč. 4, č. 2 (2009), s. 142-158 ISSN 1745-7645 R&D Projects: GA MŠk 2C06001; GA AV ČR 1ET100750401; GA MŠk 1M0572 Institutional research plan: CEZ:AV0Z10750506 Keywords : ranking * Bayesian estimation * negotiation * modelling Subject RIV: BB - Applied Statistics, Operational Research http://library.utia.cas.cz/separaty/2009/AS/karny- ranking as parameter estimation.pdf

  1. Calculation of shielding parameters

    International Nuclear Information System (INIS)

    Montoya Z, J.

    1994-01-01

    With the propose of reduce the hazard to radiation, exist three basic factors: a) time, the time to exposition to working person inside to area, from exist determined speed the doses, is proportional of the time permanence; b) distance, the reduce to doses is inverse square of the distance to exposition point; c) building, consist to interpose between source and exposition point to material. The main aspect development to the analysis of parameters distance and building. The analysis consist to development of the mathematical implicit, in the model of source radioactive, beginning with the geometry to source, distance to exposition source, and configuration building. In the final part was realize one comparative studied to calculus of parameters to blinding, employs two codes CPBGAM and MICROSHIELD, the first made as part to work thesis. The point source its a good approximation to any one real source, but in the majority of the time to propose analysis the spatial distribution of the source must realized in explicit way. The buildings calculus in volumetry's source can be approximate begin's of plan as source adaptations. It's important to have present that not only the building exist the exposition to the radiation, and the parameters time and distance plays an important paper too. (Author)

  2. LMFBR plant parameters 1991

    International Nuclear Information System (INIS)

    1991-03-01

    The document has been prepared on the basis of information provided by the members of the IAEA International Working Group on Fast Reactors (IWGFR). It contains updated parameters of 27 experimental, prototype and commercial size liquid metal fast breeder reactors (LMFBRs). Most of the reactors are currently in operation, under construction or in an advanced planning stage. Parameters of the Clinch River Breeder Reactor (USA), PEC (Italy), RAPSODIE (France), DFR (UK) and EFFBR (USA) are included in the report because of their important role in the development of LMFBR technology from first LMFBRs to the prototype size fast reactors. Two more reactors appeared in the list: European Fast Reactor (EFR) and PRISM (USA). Parameters of these reactors included in this publication are based on the data from the papers presented at the 23rd Annual Meeting of the IWGFR. All in all more than four hundred corrections and additions have been made to update the document. The report is intended for specialists and institutions in industrialized and developing countries who are responsible for the design and operation of liquid metal fast breeder reactors

  3. Desempenho produtivo, composição corporal e parâmetros fisiológicos de pacu alimentado com níveis crescentes de fibra Productive performance, body composition and physiological parameters of pacu fed increasing levels of fiber

    Directory of Open Access Journals (Sweden)

    Laurindo André Rodrigues

    2010-08-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos de teores de fibra bruta na dieta sobre o desempenho produtivo, composição centesimal da carcaça e parâmetros fisiológicos de juvenis de pacu. O experimento teve duração de 84 dias, e foram utilizados 360 juvenis de pacu, com peso médio de 23,97±0,59 g, distribuídos aleatóriamente em 30 tanques com 180 L de água, em delineamento inteiramente casualizado, com seis tratamentos (5, 7, 9, 11, 13 e 15% de fibra bruta e cinco repetições. Dietas com altos teores de fibra (11, 13 e 15% resultaram em piores taxas de ganho de peso, conversão alimentar e crescimento específico, além de menor eficiência proteica e consumo de ração. A composição da carcaça dos animais foi alterada pelo aumento do teor de fibra das dietas. Os teores de proteína e cinza tiveram aumento com o incremento nos teores de fibra. O metabolismo foi alterado com o emprego de teores crescentes de fibra, o que resultou em pequena elevação do colesterol plasmático. Teores de fibra bruta de até 9% não tiveram efeitos negativos no metabolismo; entretanto, teores acima de 11% reduziram o crescimento dos peixes.The objective of this work was to evaluate the effects of dietary crude fiber contents on productive performance, carcass composition and physiological parameters of pacu juveniles. The experiment was carried out during 84 days, 360 pacu juveniles were used with mean weight 23.97±0.59 g, stocked in 30 tanks with 180 L of water, in a completely randomized design, with six treatments (5, 7, 9, 11, 13 and 15% crude fiber and five replicates. Diets with high fiber contents (11, 13 and 15% resulted in worse rates of weight gain, feed conversion, and specific growth, besides lower protein efficiency ratio and feed consumption. Carcass composition changed by increasing the contents of dietary fiber. Body contents of protein and ash increased along with the fiber levels. The metabolism changed with the use of

  4. The 4D Composite Higgs

    CERN Document Server

    De Curtis, Stefania; Tesi, Andrea

    2012-01-01

    We propose a four dimensional description of Composite Higgs Models which represents a complete framework for the physics of the Higgs as a pseudo-Nambu-Goldstone boson. Our setup captures all the relevant features of 5D models and more in general of composite Higgs models with partial compositeness. We focus on the minimal scenario where we include a single multiplet of resonances of the composite sector, as these will be the only degrees of freedom which might be accessible at the LHC. This turns out to be sufficient to compute the effective potential and derive phenomenological consequences of the theory. Moreover our simplified approach is well adapted to simulate these models at the LHC. We also consider the impact of non-minimal terms in the effective lagrangian which do not descend from a 5D theory and could be of phenomenological relevance, for example contributing to the S-parameter.

  5. ATLAS parameter study

    International Nuclear Information System (INIS)

    Adler, R.J.

    1994-01-01

    The purpose of this study is to make an independent assessment on the parameters chosen for the ATLAS capacitor bank at LANL. The contractor will perform a study of the basic pulsed power parameters of the ATLAS device with baseline functional parameters of >25 MA implosion current and <2.5 microsecond current risetime. Nominal circuit parameters held fixed will be the 14 nH from the vacuum interface to the load, and the nominal load impedances of 1 milliohm for slow loads and 10 milliohms for fast loads. Single Ended designs, as opposed to bipolar designs, will be studied in detail. The ATLAS pulsed power design problem is about inductance. The reason that a 36 MJ bank is required is that such a bank has enough individual capacitors so that the parallel inductance is acceptably low. Since about half the inductance is in the bank, and the inductance and time constant of the submodules is fixed, the variation of output with a given parameter will generally be a weak one. In general, the dl/dt calculation demonstrates that for the real system inductances, 700 kV is the optimum voltage for the bank to drive X-ray loads. The optimum is broad, and there is little reduction in performance at voltages as low as 450 kV. The direct drive velocity analysis also shows that the optimum velocity is between 480 and 800 kV for a variety of assumptions, and that there is less than a 10% variation in velocity over this range. Voltages in the 120 kV--600 kV range are desirable for driving heavy liners. A compromise optimum operating point might be 480 kV, at which all X-ray operation scenarios are within 10% of their velocity optimum, and heavy liners can be configured to be near optimum if small enough. Based on very preliminary studies the author believes that the choice of a single operating voltage point (say, 480 kV) is unnecessary, and that a bank engineered for dual operation at 480 and 240 kV will be the best solution to the ATLAS problem

  6. Radiation portal evaluation parameters

    International Nuclear Information System (INIS)

    York, R.L.

    1998-01-01

    The detection of the unauthorized movement of radioactive materials is one of the most effective nonproliferation measures. Automatic special nuclear material (SNM) portal monitors are designed to detect this unauthorized movement and are an important part of the safeguard systems at US nuclear facilities. SNM portals differ from contamination monitors because they are designed to have high sensitivity for the low energy gamma-rays associated with highly enriched uranium (HEU) and plutonium. These instruments are now being installed at international borders to prevent the spread of radioactive contamination an SNM. In this paper the parameters important to evaluating radiation portal monitors are discussed. (author)

  7. Buncher system parameter optimization

    International Nuclear Information System (INIS)

    Wadlinger, E.A.

    1981-01-01

    A least-squares algorithm is presented to calculate the RF amplitudes and cavity spacings for a series of buncher cavities each resonating at a frequency that is a multiple of a fundamental frequency of interest. The longitudinal phase-space distribution, obtained by particle tracing through the bunching system, is compared to a desired distribution function of energy and phase. The buncher cavity parameters are adjusted to minimize the difference between these two distributions. Examples are given for zero space charge. The manner in which the method can be extended to include space charge using the 3-D space-charge calculation procedure is indicated

  8. Infrared Drying Parameter Optimization

    Science.gov (United States)

    Jackson, Matthew R.

    In recent years, much research has been done to explore direct printing methods, such as screen and inkjet printing, as alternatives to the traditional lithographic process. The primary motivation is reduction of the material costs associated with producing common electronic devices. Much of this research has focused on developing inkjet or screen paste formulations that can be printed on a variety of substrates, and which have similar conductivity performance to the materials currently used in the manufacturing of circuit boards and other electronic devices. Very little research has been done to develop a process that would use direct printing methods to manufacture electronic devices in high volumes. This study focuses on developing and optimizing a drying process for conductive copper ink in a high volume manufacturing setting. Using an infrared (IR) dryer, it was determined that conductive copper prints could be dried in seconds or minutes as opposed to tens of minutes or hours that it would take with other drying devices, such as a vacuum oven. In addition, this study also identifies significant parameters that can affect the conductivity of IR dried prints. Using designed experiments and statistical analysis; the dryer parameters were optimized to produce the best conductivity performance for a specific ink formulation and substrate combination. It was determined that for an ethylene glycol, butanol, 1-methoxy 2- propanol ink formulation printed on Kapton, the optimal drying parameters consisted of a dryer height of 4 inches, a temperature setting between 190 - 200°C, and a dry time of 50-65 seconds depending on the printed film thickness as determined by the number of print passes. It is important to note that these parameters are optimized specifically for the ink formulation and substrate used in this study. There is still much research that needs to be done into optimizing the IR dryer for different ink substrate combinations, as well as developing a

  9. LMFBR plant parameters

    International Nuclear Information System (INIS)

    1985-07-01

    This document has been prepared on the basis of information compiled by the members of the IAEA International Working Group on Fast Reactors (IWGFR). It contains parameters of 25 experimental, prototype and commercial size liquid metal fast breeder reactors (LMFBR). Most of the reactors are currently in operation, under construction or in an advanced planning stage. Parameters of the Clinch River Breeder Reactor (USA) are presented because its design was nearly finished and most of the components were fabricated at the time when the project was terminated. Three reactors (RAPSODIE (France), DFR (UK) and EFFBR (USA)) have been shut down. However, they are included in the report because of their important role in the development of LMFBR technology from first LMFBRs to the prototype size fast reactors. The first LMFBRs (CLEMENTINE (USA), EBR-1 (USA), BR-2 (USSR), BR-5 (USSR)) and very special reactors (LAMPRE (USA), SEFOR (USA)) were not recommended by the members of the IWGFR to be included in the report

  10. Multiwavelength light curve parameters of Cepheid variables

    Directory of Open Access Journals (Sweden)

    Bhardwaj Anupam

    2017-01-01

    Full Text Available We present a comparative analysis of theoretical and observed light curves of Cepheid variables using Fourier decomposition. The theoretical light curves at multiple wavelengths are generated using stellar pulsation models for chemical compositions representative of Cepheids in the Galaxy and Magellanic Clouds. The observed light curves at optical (VI, near-infrared (JHKs and mid-infrared (3.6 & 4.5-μm bands are compiled from the literature. We discuss the variation of light curve parameters as a function of period, wavelength and metallicity. Theoretical and observed Fourier amplitude parameters decrease with increase in wavelength while the phase parameters increase with wavelength. We find that theoretical amplitude parameters obtained using canonical mass-luminosity levels exhibit a greater offset with respect to observations when compared to non-canonical relations. We also discuss the impact of variation in convective efficiency on the light curve structure of Cepheid variables. The increase in mixing length parameter results in a zero-point offset in bolometric mean magnitudes and reduces the systematic large difference in theoretical amplitudes with respect to observations.

  11. Concrete compositions and methods

    Science.gov (United States)

    Chen, Irvin; Lee, Patricia Tung; Patterson, Joshua

    2015-06-23

    Provided herein are compositions, methods, and systems for cementitious compositions containing calcium carbonate compositions and aggregate. The compositions find use in a variety of applications, including use in a variety of building materials and building applications.

  12. 立式浅盆型复合种盘大豆排种器结构设计与参数优化%Design and Parameter Optimization on Vertical Shallow-basin Type Composites Seed-plate Soybean Seed-metering Devices

    Institute of Scientific and Technical Information of China (English)

    刘宏新; 徐晓萌; 付露露; 王晨

    2016-01-01

    为满足机械式精密排种器高速作业的要求,以增加充填力的方式对立式圆盘排种器进行改进,设计了一种利用重力与离心力以及种子间相互作用力作为复合力进行充种的双腔立式浅盆型复合种盘机械式精密排种器,并对排种盘的特征参数进行了优化.利用离散元仿真分析软件 EDEM对立式浅盆型种盘进行了以排种盘直径、折边倾角、作业速度为影响因素,充填率为性能指标的三因素五水平二次正交旋转组合仿真设计,并运用Design-expert 8.0软件对数据进行了处理,获得了排种盘最优的结构参数组合,同时利用物理样机试验进行了验证.研究结果表明:立式浅盆型种盘的最佳结构参数组合为排种盘直径234 mm、折边倾角68°,在8~12 km/h高速作业时,合格率均能达到90%以上.研究结果为产品定型提供了定量的依据.%To meet the working requirements of mechanical precision seed-metering device at high speed,a vertical shallow basin-type composite seed-plate seed-metering device with double cavity was designed,the seed-metering device might utilize gravity,centrifugal force and interaction force among the seeds to increase the filling force,improve the filling performance of seed-metering device at high speed.And in order to obtain the structure parameters of seed-metering devices to further improve the quality of precision seeding,the software of EDEM was utilized to make the three factors and five lev-els of all factors rotational quadratic orthogonal experiments which took the diameter of seed-plate, folding angle,working speed as the influence factors,and filling rate as the performance index,the experimental scheme was designed.And Design-expert 8.0 software was used to deal with the simula-tion data,the optimal structural parameters of the seed plate were obtained,the physical prototype test was made to verify the values of simulation.The experimental

  13. Milk composition of Yankasa sheep raised under small-holder ...

    African Journals Online (AJOL)

    The results showed that there were significant differences (P<0.05) in milk compositional parameters with respect to total solid, lactose, crude protein (CP) and fat contents pH and ash contents were influenced by BCS of the ewes studied. Age of ewes significantly (P<0.05) affected all the milk composition parameters ...

  14. Biochemical composition and methane production correlations

    OpenAIRE

    Charnier, Cyrille; Latrille, Eric; Moscoviz, Roman; Miroux, Jérémie; Steyer, Jean-Philippe

    2016-01-01

    Substrates for anaerobic digestion are composed of heterogeneous and complex organic matter. General parameters of the organic matter can be used to describe its composition such as sugar, protein and lipid contents, Chemical Oxygen Demand (COD), Biochemical Methane Potential (BMP) and kinetic of methane production. These parameters are required for the monitoring of digesters but their characterization are time consuming and expensive; thus, these parameters are rarely assessed all together....

  15. Display Parameters and Requirements

    Science.gov (United States)

    Bahadur, Birendra

    The following sections are included: * INTRODUCTION * HUMAN FACTORS * Anthropometry * Sensory * Cognitive * Discussions * THE HUMAN VISUAL SYSTEM - CAPABILITIES AND LIMITATIONS * Cornea * Pupil and Iris * Lens * Vitreous Humor * Retina * RODS - NIGHT VISION * CONES - DAY VISION * RODS AND CONES - TWILIGHT VISION * VISUAL PIGMENTS * MACULA * BLOOD * CHOROID COAT * Visual Signal Processing * Pathways to the Brain * Spatial Vision * Temporal Vision * Colour Vision * Colour Blindness * DICHROMATISM * Protanopia * Deuteranopia * Tritanopia * ANOMALOUS TRICHROMATISM * Protanomaly * Deuteranomaly * Tritanomaly * CONE MONOCHROMATISM * ROD MONOCHROMATISM * Using Colour Effectively * COLOUR MIXTURES AND THE CHROMATICITY DIAGRAM * Colour Matching Functions and Chromaticity Co-ordinates * CIE 1931 Colour Space * CIE PRIMARIES * CIE COLOUR MATCHING FUNCTIONS AND CHROMATICITY CO-ORDINATES * METHODS FOR DETERMINING TRISTIMULUS VALUES AND COLOUR CO-ORDINATES * Spectral Power Distribution Method * Filter Method * CIE 1931 CHROMATICITY DIAGRAM * ADDITIVE COLOUR MIXTURE * CIE 1976 Chromaticity Diagram * CIE Uniform Colour Spaces and Colour Difference Formulae * CIELUV OR L*u*v* * CIELAB OR L*a*b* * CIE COLOUR DIFFERENCE FORMULAE * Colour Temperature and CIE Standard Illuminants and source * RADIOMETRIC AND PHOTOMETRIC QUANTITIES * Photopic (Vλ and Scotopic (Vλ') Luminous Efficiency Function * Photometric and Radiometric Flux * Luminous and Radiant Intensities * Incidence: Illuminance and Irradiance * Exitance or Emittance (M) * Luminance and Radiance * ERGONOMIC REQUIREMENTS OF DISPLAYS * ELECTRO-OPTICAL PARAMETERS AND REQUIREMENTS * Contrast and Contrast Ratio * Luminance and Brightness * Colour Contrast and Chromaticity * Glare * Other Aspects of Legibility * SHAPE AND SIZE OF CHARACTERS * DEFECTS AND BLEMISHES * FLICKER AND DISTORTION * ANGLE OF VIEW * Switching Speed * Threshold and Threshold Characteristic * Measurement Techniques For Electro-optical Parameters * RADIOMETRIC

  16. Timetable Attractiveness Parameters

    DEFF Research Database (Denmark)

    Schittenhelm, Bernd

    2008-01-01

    Timetable attractiveness is influenced by a set of key parameters that are described in this article. Regarding the superior structure of the timetable, the trend in Europe goes towards periodic regular interval timetables. Regular departures and focus on optimal transfer possibilities make...... these timetables attractive. The travel time in the timetable depends on the characteristics of the infrastructure and rolling stock, the heterogeneity of the planned train traffic and the necessary number of transfers on the passenger’s journey. Planned interdependencies between trains, such as transfers...... and heterogeneous traffic, add complexity to the timetable. The risk of spreading initial delays to other trains and parts of the network increases with the level of timetable complexity....

  17. Parameter measurement of target

    International Nuclear Information System (INIS)

    Gao Dangzhong

    2001-01-01

    The progress of parameter measurement of target (ICF-15) in 1999 are presented, including the design and contract of the microsphere equator profiler, the precise air bearing manufacturing, high-resolution X-ray image of multi-layer shells and the X-ray photos processed with special image and data software, some plastic shells measured in precision of 0.3 μm, the high-resolution observation and photograph system of 'dew-point method', special fixture of target and its temperature distribution measuring, the dew-point temperature and fuel gas pressure of shells measuring with internal pressure of 5 - 15 (x10 5 ) Pa D 2 and wall thickness of 1.5∼3 μm

  18. Safety Parameters Graphical Interface

    International Nuclear Information System (INIS)

    Canamero, B.

    1998-01-01

    Nuclear power plant data are received at the Operations Center of the Consejo de Seguridad Nuclear in emergency situations. In order to achieve the required interface and to prepare those data to perform simulation and forecasting with already existing computer codes a Safety Parameters Graphical Interface (IGPS) has been developed. The system runs in a UNIX environment and use the Xwindows capabilities. The received data are stored in such a way that it can be easily used for further analysis and training activities. The system consists of task-oriented modules (processes) which communicate each other using well known UNIX mechanisms (signals, sockets and shared memory segments). IGPS conceptually have two different parts: Data collection and preparation, and Data monitorization. (Author)

  19. varying elastic parameters distributions

    KAUST Repository

    Moussawi, Ali

    2014-12-01

    The experimental identication of mechanical properties is crucial in mechanics for understanding material behavior and for the development of numerical models. Classical identi cation procedures employ standard shaped specimens, assume that the mechanical elds in the object are homogeneous, and recover global properties. Thus, multiple tests are required for full characterization of a heterogeneous object, leading to a time consuming and costly process. The development of non-contact, full- eld measurement techniques from which complex kinematic elds can be recorded has opened the door to a new way of thinking. From the identi cation point of view, suitable methods can be used to process these complex kinematic elds in order to recover multiple spatially varying parameters through one test or a few tests. The requirement is the development of identi cation techniques that can process these complex experimental data. This thesis introduces a novel identi cation technique called the constitutive compatibility method. The key idea is to de ne stresses as compatible with the observed kinematic eld through the chosen class of constitutive equation, making possible the uncoupling of the identi cation of stress from the identi cation of the material parameters. This uncoupling leads to parametrized solutions in cases where 5 the solution is non-unique (due to unknown traction boundary conditions) as demonstrated on 2D numerical examples. First the theory is outlined and the method is demonstrated in 2D applications. Second, the method is implemented within a domain decomposition framework in order to reduce the cost for processing very large problems. Finally, it is extended to 3D numerical examples. Promising results are shown for 2D and 3D problems.

  20. Process Damping Parameters

    International Nuclear Information System (INIS)

    Turner, Sam

    2011-01-01

    The phenomenon of process damping as a stabilising effect in milling has been encountered by machinists since milling and turning began. It is of great importance when milling aerospace alloys where maximum surface speed is limited by excessive tool wear and high speed stability lobes cannot be attained. Much of the established research into regenerative chatter and chatter avoidance has focussed on stability lobe theory with different analytical and time domain models developed to expand on the theory first developed by Trusty and Tobias. Process damping is a stabilising effect that occurs when the surface speed is low relative to the dominant natural frequency of the system and has been less successfully modelled and understood. Process damping is believed to be influenced by the interference of the relief face of the cutting tool with the waveform traced on the cut surface, with material properties and the relief geometry of the tool believed to be key factors governing performance. This study combines experimental trials with Finite Element (FE) simulation in an attempt to identify and understand the key factors influencing process damping performance in titanium milling. Rake angle, relief angle and chip thickness are the variables considered experimentally with the FE study looking at average radial and tangential forces and surface compressive stress. For the experimental study a technique is developed to identify the critical process damping wavelength as a means of measuring process damping performance. For the range of parameters studied, chip thickness is found to be the dominant factor with maximum stable parameters increased by a factor of 17 in the best case. Within the range studied, relief angle was found to have a lesser effect than expected whilst rake angle had an influence.

  1. Composite materials

    International Nuclear Information System (INIS)

    Sambrook, D.J.

    1976-01-01

    A superconductor composite is described comprising at least one longitudinally extending superconductor filament or bundle of sub-filaments, each filament or bundle of sub-filaments being surrounded by and in good electrical contact with a matrix material, the matrix material comprising a plurality of longitudinally extending cells of a metal of high electrical conductivity surrounded by a material of lower electrical conductivity. The high electrical conductivity material surrounding the superconducting filament or bundle of sub-filaments is interrupted by a radially extending wall of the material of the lower electrical conductivity, the arrangement being such that at least two superconductor filaments or sub-filaments are circumferentially circumscribed by a single annulus of the material of high electrical conductivity. The annulus is electrically interrupted by a radially extending wall of the material of low electrical conductivity

  2. Acrylic composition

    International Nuclear Information System (INIS)

    Kimura, Tadashi; Ozeki, Takao; Kobayashi, Juichi; Nakamoto, Hideo; Meda, Yutaka.

    1969-01-01

    An acrylic composition and a process for the production of an easily hardenable coating material by irradiating with active energy, particularly electron beams and ultraviolet light, are provided using a mixture of 10%-100% by weight of an unsaturated compound and 90%-0% of a vinyl monomer. The composition has a high degree of polymerization, low volatility, low viscosity and other properties similar to thermosetting acrylic or amino alkyd resins. The aforesaid unsaturated compound is produced by primarily reacting saturated cyclocarboxylic anhydride and/or alpha-, beta-ethylene unsaturated carboxylic anhydride and by secondarily reacting an epoxy radical-containing vinyl monomer by addition reaction with polyhydric alcohols. Each reaction is conducted in the presence of a tertiary amino radical-containing vinyl monomer as a catalyst. The cross-linking is effected generally with an electron beam accelerator of 0.1-2.0 MeV or with a light beam in the 2,000-8,000A range in the presence of a photosensitive agent. In one example, 62 parts of ethylene glycol and 196 parts of maleic anhydride were dissolved in a mixture consisting of 100 parts of n-butyl methacrylate and 30 parts of styrene. To the mixture were added 5 parts of 2-methyl 5 vinyl piridine and 0.005 part of hydroquinone monomethyl ether. After the reaction at 90 0 C for 3 hours, a compound HOC:O-CH=CHC:OCH 2 CH 2 C:OOH was produced. To this solution were added 285 parts of glycidyl methacrylate. After the reaction at 90 0 C for 6 hours, 95% of the carboxylic acids reacted with epoxy radicals. Fourteen examples are given. (Iwakiri, K.)

  3. Prediction of the Chemical Composition and Fermentation Parameters of Pasture Silage by Near Infrered Reflectance Spectroscopy (NIRS Predicción de la Composición Química y Parámetros Fermentativos de Ensilajes de Pradera Mediante Espectroscopía de Reflectancia en el Infrarrojo Cercano (NIRS

    Directory of Open Access Journals (Sweden)

    Lorena Ibáñez

    2008-12-01

    Full Text Available The capability of near infrared reflectance spectroscopy (NIRS was evaluated to predict the content of total ash (TA, crude protein (CP, crude fiber (CF, neutral detergent fiber (NDF, acid detergent fiber (ADF and metabolizable energy (ME; as well as pH and ammonia nitrogen content (N-NH3, in pasture silage, with and without additives. Nine hundred and twenty dried and ground samples of pasture silage, with known chemical composition, were scanned over the visible and NIR region (400 to 2500 nm at 2 nm intervals. Calibration equations were developed by modified partial least square regression models (MPLS with different mathematical treatments and light scatter correction as standard normal variation and Detrend (SNV & D of the spectra. For each parameter, the optimum calibration was evaluated on the basis of the cross validation determination coefficient (1-VR and standard error of cross validation (SECV. NIRS showed a high predictive ability, with 1-VR > 0.89 and SECV (% of 5.14, 6.69, 9.96, 16.01 and 9.15 for A, CP, CF, NDF and ADF, respectively. NIRS showed moderate accuracy for ME, with 1-VR > 0.87, SECV: 0.07 Mcal kg-1 and low accuracy, although with feasibility as a ranking method, for pH and N-NH3, with 1-VR > 0.72 and SECV of 0.14 and 1.49, respectively. It is concluded that the equations obtained can be used to predict the nutritional composition of pasture silages.Se evaluó la capacidad de la espectroscopía de reflectancia en el infrarrojo cercano (NIRS para predecir la composición química: cenizas totales (CT, proteína cruda (PC, fibra cruda (FC, fibra detergente neutro (FDN, fibra detergente ácido (FDA, energía metabolizable (EM y parámetros fermentativos: pH y nitrógeno amoniacal (N-NH3, en ensilajes de pradera con y sin aditivos. Se tomaron espectros (400 a 2500 nm, cada 2 nm de muestras secas y molidas (n = 920 de ensilajes de pradera con composición química conocida. Se desarrollaron calibraciones evaluando diferentes

  4. Quality parameters of curd

    Directory of Open Access Journals (Sweden)

    Roman Pytel

    2017-01-01

    Full Text Available The aim of this work was measurement of the curd firmness prepared by different volume of rennet solution and comparison of differences of curd firmness between these volumes. Further, it was observed the influence of different volumes of rennet up to thevolume of whey release, curd firmness, dry matter of curd and dry matter of whey. The composition of milk was determined according ISO and Czech state standard. Dry matter content (% was determined by gravimetry, in drying oven at 102 °C to constant weight (ISO 6731:2010, the protein content (% by Kjeldahl´s method (EN ISO 8968-1:2002, content of fat (% by Gerber´s acidobutyrometric method (ISO 2446:2008, content of lactose by polarimetry, titratable acidity by titration Soxhlet-Henkel method, pH and calcium content in milk (g.L-1 was determined by complexometric titration with flueroxone as an indicator according to Czech state standart No 57 0530. For coagulation was used microbial rennet CHY-MAXRM 200. There were measured: curd firmness, rennet coagulation time, curd quality, volume of released whey, weight of curd, dry matter of curd and dry matter of whey. Different volumes of rennet solution had influence on curd firmness. Curd firmness (volume of rennet solution had no significant influence on curd quality (five grade scale. Curd firmness had influence on volume of whey release (mL out of the curd. With the increasing curd firmness s increased the volume of whey released from the curd. The volume of rennet solution had an influence on weight of curd. Curd dry matter raised with higher volume of rennet solution. Volume of added rennet solution had no statistically significant effect on the change of whey dry matter. 

  5. [Acoustical parameters of toys].

    Science.gov (United States)

    Harazin, Barbara

    2010-01-01

    Toys play an important role in the development of the sight and hearing concentration in children. They also support the development of manipulation, gently influence a child and excite its emotional activities. A lot of toys emit various sounds. The aim of the study was to assess sound levels produced by sound-emitting toys used by young children. Acoustical parameters of noise were evaluated for 16 sound-emitting plastic toys in laboratory conditions. The noise level was recorded at four different distances, 10, 20, 25 and 30 cm, from the toy. Measurements of A-weighted sound pressure levels and noise levels in octave band in the frequency range from 31.5 Hz to 16 kHz were performed at each distance. Taking into consideration the highest equivalent A-weighted sound levels produced by tested toys, they can be divided into four groups: below 70 dB (6 toys), from 70 to 74 dB (4 toys), from 75 to 84 dB (3 toys) and from 85 to 94 dB (3 toys). The majority of toys (81%) emitted dominant sound levels in octave band at the frequency range from 2 kHz to 4 kHz. Sound-emitting toys produce the highest acoustic energy at the frequency range of the highest susceptibility of the auditory system. Noise levels produced by some toys can be dangerous to children's hearing.

  6. Centesimal composition and physicochemical parameters of meat from santa inês lambs fed with passion fruit peelComposição centesimal e parâmetros físico-químicos da carne de cordeiros santa inês alimentados com casca de maracúja

    Directory of Open Access Journals (Sweden)

    Cristiane Leal dos Santos-Cruz

    2013-09-01

    Full Text Available The objective was to determine the centesimal composition and some physicochemical parameters in the longissimus lumborum muscle from non castrated Santa Ines lambs, fed diets containing different proportions of passion fruit peel, in the following treatments: T1: 100% elephant grass, T2: 90% elephant grass + 10% dried passion fruit peel, T3: 80% elephant grass + 20% dried passion fruit peel, T4: 70% elephant grass + 30% dried passion fruit peel based on the elephant grass natural matter. The inclusion of 30% passion fruit peel in the diet of Santa Inez lambs turned the meat less intensely red (a = 7.40 but with a stronger hue (h = 59.75 than that resulting from the 10% addition. The water retention capacity was higher in the meat of lambs fed 30% passion fruit peel, as well as, shear force (0.50 and pH (6.40, but these values are adequate to assure quality. Protein content, minerals and energy did not change, but neither did their values fall below the level desired by industry. Lipid content was higher in the meat of lambs fed 20% of passion fruit peel. Therefore, the inclusion of 30% of passion fruit peel in the silage of growing Santa Inês lambs is recommended, because it improves the quality and nutritional parameters of the meat. Objetivou-se determinar a composição centesimal e alguns parâmetros físico químicos no músculo Longissimus lumborum de 16 cordeiros Santa Inês, não castrados, alimentados com diferentes dietas contendo casca desidratada de maracujá, sendo os tratamentos T1: 100% capim elefante; T2: 90% capim elefante + 10% casca desidratada de maracujá; T3: 80% capim elefante + 20% casca desidratada de maracujá; T4: 70% capim elefante + 30% casca desidratada de maracujá com base na matéria natural do capim elefante. A inclusão de 30% de casca desidratada de maracujá na dieta de cordeiros Santa Inês tornou a carne com um vermelho menos intenso (a=7,40, mas com grau de tonalidade maior (h=59,75 em relação

  7. Metallic composite materials

    International Nuclear Information System (INIS)

    Frommeyer, G.

    1987-01-01

    The structure and properties of metallic composite materials and composite materials with metallic matrix are considered. In agreement with the morphology of constituent phases the following types of composite materials are described: dispersion-strengthened composite materials; particle-reinforced composite materials; fibrous composite materials; laminar composite materials. Data on strength and electric properties of the above-mentioned materials, as well as effect of the amount, location and geometric shape of the second phase on them, are presented

  8. Composite Techniques Based Color Image Compression

    Directory of Open Access Journals (Sweden)

    Zainab Ibrahim Abood

    2017-03-01

    Full Text Available Compression for color image is now necessary for transmission and storage in the data bases since the color gives a pleasing nature and natural for any object, so three composite techniques based color image compression is implemented to achieve image with high compression, no loss in original image, better performance and good image quality. These techniques are composite stationary wavelet technique (S, composite wavelet technique (W and composite multi-wavelet technique (M. For the high energy sub-band of the 3rd level of each composite transform in each composite technique, the compression parameters are calculated. The best composite transform among the 27 types is the three levels of multi-wavelet transform (MMM in M technique which has the highest values of energy (En and compression ratio (CR and least values of bit per pixel (bpp, time (T and rate distortion R(D. Also the values of the compression parameters of the color image are nearly the same as the average values of the compression parameters of the three bands of the same image.

  9. Parameters of care for craniosynostosis

    DEFF Research Database (Denmark)

    McCarthy, Joseph G; Warren, Stephen M; Bernstein, Joseph

    2012-01-01

    A multidisciplinary meeting was held from March 4 to 6, 2010, in Atlanta, Georgia, entitled "Craniosynostosis: Developing Parameters for Diagnosis, Treatment, and Management." The goal of this meeting was to create parameters of care for individuals with craniosynostosis.......A multidisciplinary meeting was held from March 4 to 6, 2010, in Atlanta, Georgia, entitled "Craniosynostosis: Developing Parameters for Diagnosis, Treatment, and Management." The goal of this meeting was to create parameters of care for individuals with craniosynostosis....

  10. Subsurface Geotechnical Parameters Report

    International Nuclear Information System (INIS)

    Rigby, D.; Mrugala, M.; Shideler, G.; Davidsavor, T.; Leem, J.; Buesch, D.; Sun, Y.; Potyondy, D.; Christianson, M.

    2003-01-01

    The Yucca Mountain Project is entering a the license application (LA) stage in its mission to develop the nation's first underground nuclear waste repository. After a number of years of gathering data related to site characterization, including activities ranging from laboratory and site investigations, to numerical modeling of processes associated with conditions to be encountered in the future repository, the Project is realigning its activities towards the License Application preparation. At the current stage, the major efforts are directed at translating the results of scientific investigations into sets of data needed to support the design, and to fulfill the licensing requirements and the repository design activities. This document addresses the program need to address specific technical questions so that an assessment can be made about the suitability and adequacy of data to license and construct a repository at the Yucca Mountain Site. In July 2002, the U.S. Nuclear Regulatory Commission (NRC) published an Integrated Issue Resolution Status Report (NRC 2002). Included in this report were the Repository Design and Thermal-Mechanical Effects (RDTME) Key Technical Issues (KTI). Geotechnical agreements were formulated to resolve a number of KTI subissues, in particular, RDTME KTIs 3.04, 3.05, 3.07, and 3.19 relate to the physical, thermal and mechanical properties of the host rock (NRC 2002, pp. 2.1.1-28, 2.1.7-10 to 2.1.7-21, A-17, A-18, and A-20). The purpose of the Subsurface Geotechnical Parameters Report is to present an accounting of current geotechnical information that will help resolve KTI subissues and some other project needs. The report analyzes and summarizes available qualified geotechnical data. It evaluates the sufficiency and quality of existing data to support engineering design and performance assessment. In addition, the corroborative data obtained from tests performed by a number of research organizations is presented to reinforce

  11. Subsurface Geotechnical Parameters Report

    Energy Technology Data Exchange (ETDEWEB)

    D. Rigby; M. Mrugala; G. Shideler; T. Davidsavor; J. Leem; D. Buesch; Y. Sun; D. Potyondy; M. Christianson

    2003-12-17

    The Yucca Mountain Project is entering a the license application (LA) stage in its mission to develop the nation's first underground nuclear waste repository. After a number of years of gathering data related to site characterization, including activities ranging from laboratory and site investigations, to numerical modeling of processes associated with conditions to be encountered in the future repository, the Project is realigning its activities towards the License Application preparation. At the current stage, the major efforts are directed at translating the results of scientific investigations into sets of data needed to support the design, and to fulfill the licensing requirements and the repository design activities. This document addresses the program need to address specific technical questions so that an assessment can be made about the suitability and adequacy of data to license and construct a repository at the Yucca Mountain Site. In July 2002, the U.S. Nuclear Regulatory Commission (NRC) published an Integrated Issue Resolution Status Report (NRC 2002). Included in this report were the Repository Design and Thermal-Mechanical Effects (RDTME) Key Technical Issues (KTI). Geotechnical agreements were formulated to resolve a number of KTI subissues, in particular, RDTME KTIs 3.04, 3.05, 3.07, and 3.19 relate to the physical, thermal and mechanical properties of the host rock (NRC 2002, pp. 2.1.1-28, 2.1.7-10 to 2.1.7-21, A-17, A-18, and A-20). The purpose of the Subsurface Geotechnical Parameters Report is to present an accounting of current geotechnical information that will help resolve KTI subissues and some other project needs. The report analyzes and summarizes available qualified geotechnical data. It evaluates the sufficiency and quality of existing data to support engineering design and performance assessment. In addition, the corroborative data obtained from tests performed by a number of research organizations is presented to reinforce

  12. WIPP Compliance Certification Application calculations parameters. Part 1: Parameter development

    International Nuclear Information System (INIS)

    Howarth, S.M.

    1997-01-01

    The Waste Isolation Pilot Plant (WIPP) in southeast New Mexico has been studied as a transuranic waste repository for the past 23 years. During this time, an extensive site characterization, design, construction, and experimental program was completed, which provided in-depth understanding of the dominant processes that are most likely to influence the containment of radionuclides for 10,000 years. Nearly 1,500 parameters were developed using information gathered from this program; the parameters were input to numerical models for WIPP Compliance Certification Application (CCA) Performance Assessment (PA) calculations. The CCA probabilistic codes frequently require input values that define a statistical distribution for each parameter. Developing parameter distributions begins with the assignment of an appropriate distribution type, which is dependent on the type, magnitude, and volume of data or information available. The development of the parameter distribution values may require interpretation or statistical analysis of raw data, combining raw data with literature values, scaling of lab or field data to fit code grid mesh sizes, or other transformation. Parameter development and documentation of the development process were very complicated, especially for those parameters based on empirical data; they required the integration of information from Sandia National Laboratories (SNL) code sponsors, parameter task leaders (PTLs), performance assessment analysts (PAAs), and experimental principal investigators (PIs). This paper, Part 1 of two parts, contains a discussion of the parameter development process, roles and responsibilities, and lessons learned. Part 2 will discuss parameter documentation, traceability and retrievability, and lessons learned from related audits and reviews

  13. Visco-piezo-elastic parameter estimation in laminated plate structures

    DEFF Research Database (Denmark)

    Araujo, A. L.; Mota Soares, C. M.; Herskovits, J.

    2009-01-01

    A parameter estimation technique is presented in this article, for identification of elastic, piezoelectric and viscoelastic properties of active laminated composite plates with surface-bonded piezoelectric patches. The inverse method presented uses experimental data in the form of a set of measu...

  14. Modelling hydrodynamic parameters to predict flow assisted corrosion

    International Nuclear Information System (INIS)

    Poulson, B.; Greenwell, B.; Chexal, B.; Horowitz, J.

    1992-01-01

    During the past 15 years, flow assisted corrosion has been a worldwide problem in the power generating industry. The phenomena is complex and depends on environment, material composition, and hydrodynamic factors. Recently, modeling of flow assisted corrosion has become a subject of great importance. A key part of this effort is modeling the hydrodynamic aspects of this issue. This paper examines which hydrodynamic parameter should be used to correlate the occurrence and rate of flow assisted corrosion with physically meaningful parameters, discusses ways of measuring the relevant hydrodynamic parameter, and describes how the hydrodynamic data is incorporated into the predictive model

  15. Muonium hyperfine parameters in Si1-x Ge x alloys

    International Nuclear Information System (INIS)

    King, Philip; Lichti, Roger; Cottrell, Stephen; Yonenaga, Ichiro

    2006-01-01

    We present studies of muonium behaviour in bulk, Czochralski-grown Si 1- x Ge x alloy material, focusing in particular on the hyperfine parameter of the tetrahedral muonium species. In contrast to the bond-centred species, the hyperfine parameter of the tetrahedral-site muonium centre (Mu T ) appears to vary non-linearly with alloy composition. The temperature dependence of the Mu T hyperfine parameter observed in low-Ge alloy material is compared with that seen in pure Si, and previous models of the Mu T behaviour in Si are discussed in the light of results from Si 1- x Ge x alloys

  16. Shaped fiber composites

    Science.gov (United States)

    Kinnan, Mark K.; Roach, Dennis P.

    2017-12-05

    A composite article is disclosed that has non-circular fibers embedded in a polymer matrix. The composite article has improved damage tolerance, toughness, bending, and impact resistance compared to composites having traditional round fibers.

  17. Confirmatory Composite Analysis

    NARCIS (Netherlands)

    Schuberth, Florian; Henseler, Jörg; Dijkstra, Theo K.

    2018-01-01

    We introduce confirmatory composite analysis (CCA) as a structural equation modeling technique that aims at testing composite models. CCA entails the same steps as confirmatory factor analysis: model specification, model identification, model estimation, and model testing. Composite models are

  18. Composition superconductive plumbous coatings

    International Nuclear Information System (INIS)

    Volodin, V.N.; Tuleushev, A.Zh.; Tuleushev, Yu.Zh.; Lisizin, V.N.

    2002-01-01

    Independent dispersion of two or more targets, precipitation of pulverized material on substrate and possibility of composition change in wide range of component concentrations made possible ion-plasma forming of film composition materials from materials with different chemical and physical qualities, particularly in lead-aluminum, lead-beryllium and lead-graphite systems. Named systems are characterized in wide sphere of immiscibility in solid and liquid state and absence of intermediate compounds. It is impossible to receive materials from them in traditional method in conditions of gravitational field. In lead-aluminum system there was received a number of film coatings with aluminum content up to 95 at. % at coating thickness up to 2 μm. Owing to X-ray investigations it is fixed that lead and aluminum have been performed by separate phases. Lead in sprayed layer represents well-crystallized phase with grain size more than 100 nm; texturing is not found. Study of physical qualities has shown that materials with lead base 21.6 at. % Al) have enough high crystalline current in comparison with compact lead, which reaches (2.5-3.0)·10 5 A)·cm 2 , while materials with aluminum base (21.6 at. % Al) loose this effect and critical temperature of transition is reduced from 7.1 to 5.8 K. It was impossible to carry out X-rayed analysis for lead-beryllium film because of weak intensity of beryllium lines against a background of lead owing to a quite large difference of atomic balance. Cryogen tests have shown the increase of critical current strength up to (3.1-3.6)·10 4 A)·cm 2 or composition coating of lead-beryllium (56.99 at. % or 5,45 mas. % Be), at that the critical temperature of transition does not differ from lead temperature. Samples of lead edge of state diagram have been received in the lead-graphite system. X-ray investigation subjected coating contained 6.81 at. % (55.82 mas. %) of lead. Choice of the composition is conditioned on possibilities of

  19. Properties of CMR composites

    Indian Academy of Sciences (India)

    Unknown

    Department of Metallurgical Engineering and Materials Science, Indian. Institute ... Colossal magnetoresistance (CMR) composites form an interesting field ..... field and composition sensitive competition between the positive and negative MR.

  20. Composite Structures Manufacturing Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Composite Structures Manufacturing Facility specializes in the design, analysis, fabrication and testing of advanced composite structures and materials for both...

  1. Composites Characterization Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The purpose of the Composites Characterization Laboratory is to investigate new and/or modified matrix materials and fibers for advanced composite applications both...

  2. Measurement of opalescence of resin composites.

    Science.gov (United States)

    Lee, Yong-Keun; Lu, Huan; Powers, John M

    2005-11-01

    Opalescence is an optical property, where there is light scattering of the shorter wavelengths of the visible spectrum, giving the material a bluish appearance under reflected light and an orange/brown appearance under transmitted light. The objective of this study was to determine the opalescence of resin composites with a color measuring spectrophotometer. Colors of A2 and enamel or translucent shades of four resin composites and of an unfilled resin measured in the reflectance and transmittance modes were compared, and the opalescence parameter (OP) was calculated as the difference in blue-yellow coordinate (Deltab*) and red-green parameter (Deltaa*) between the reflected and transmitted colors of 1-mm thick specimens. The masking effect was calculated as the color difference between the color of a black background and the color of specimen over the black background. The range of OP in resin composites was 5.7-23.7, which was higher than that of the unfilled resin. However, there were significant differences among the brands and shades of the resin composites. Opalescence varied by brand and shade of the resin composites, and contributed to the masking of background color along with translucency parameter. Some of the resin composites actually displayed opalescence.

  3. Physicochemical parameters of Amazon Melipona honey

    Directory of Open Access Journals (Sweden)

    Ligia Bicudo de Almeida-Muradian

    2007-06-01

    Full Text Available Stingless bees produce a honey that is different from the Apis honey in terms of composition. There aren't enough data to establish quality control parameters for this product, mainly due to lack of research results. The aim of this work is to evaluate some physicochemical parameters that can be used for the characterization and for the quality control of the Meliponinae honey. Four different samples were collected in the Amazon region of Brazil in 2004 (Melipona compressipes manaoense bee and Melipona seminigra merribae bee. Honey analyses were performed as described by the official methods. The mean results were: moisture (30.13%, pH (3.65, acidity (24.57 mEq/kg, water activity (0.75, fructose (31.91%, glucose (29.30% and sucrose (0.19%. These results reinforce the need for a specific regulation for stingless bee honey. This will only be feasible when enough data is available to establish upper and lower limits for the physicochemical parameters used for quality control.

  4. Elastic Property Simulation of Nano-particle Reinforced Composites

    Directory of Open Access Journals (Sweden)

    He Jiawei

    2016-01-01

    Full Text Available A series of numerical micro-mechanical models for two kinds of particle (cylindrical and discal particle reinforced composites are developed to investigate the effect of microstructural parameters on the elastic properties of composites. The effects of both the degree of particle clustering and particle’s shape on the elastic mechanical properties of composites are investigated. In addition, single particle unit cell approximation is good enough for the analysis of the effect of averaged parameters when only linear elastic response is considered without considering the particle clustering in particle-reinforced composites.

  5. Improved Estimates of Thermodynamic Parameters

    Science.gov (United States)

    Lawson, D. D.

    1982-01-01

    Techniques refined for estimating heat of vaporization and other parameters from molecular structure. Using parabolic equation with three adjustable parameters, heat of vaporization can be used to estimate boiling point, and vice versa. Boiling points and vapor pressures for some nonpolar liquids were estimated by improved method and compared with previously reported values. Technique for estimating thermodynamic parameters should make it easier for engineers to choose among candidate heat-exchange fluids for thermochemical cycles.

  6. Study of Body Composition by Impedance Analysis

    Science.gov (United States)

    González-Solís, J. L.; Vargas-Luna, M.; Sosa-Aquino, M.; Bernal-Alvarado, J.; Gutiérrez-Juárez, G.; Huerta-Franco, R.; Sanchis-Sabater, A.

    2002-08-01

    This work presents a set of impedance measurements and preliminary results on the analysis of body composition using impedance spectroscopy. This study is made using a pork meat sample and spectra from fat and flesh region were independently obtained using the same electrodes array. From these measurements, and theoretical considerations, it is possible to explain the behavior of the composite sample flesh-fat-flesh and, fitting the electrical parameters of the model, it shows the plausibility of a physical and quantitative application to human corporal composition.

  7. Systematic of delayed neutron parameters

    International Nuclear Information System (INIS)

    Isaev, S.G.; Piksaikin, V.M.

    2000-01-01

    The experimental studies of the energy dependence of the delayed neutron (DN) parameters for various fission systems has shown that the behaviour of a some combination of delayed neutron parameters has a similar features. On the basis of this findings the systematics of delayed neutron experimental data for thorium, uranium, plutonium and americium isotopes have been investigated with the purpose to find a correlation of DN parameters with characteristics of fissioning system as well as a correlation between the delayed neutron parameters themselves. It was presented the preliminary results which were obtained during study the physics interpretation of the results [ru

  8. Fluid Effects in Polymers and Polymeric Composites

    CERN Document Server

    Weitsman, Y Jack

    2012-01-01

    Fluid Effects in Polymers and Polymeric Composites, written by the late Dr. Y. Jack Weitsman, addresses the wide range of parameters that affect the interaction of fluids with polymers and polymeric composites. The book aims at broadening the scope of available data, mostly limited up to this time to weight-gain recordings of fluid ingress into polymers and composites, to the practical circumstances of fluctuating exposure. Various forms of experimental data are given, in conjunction with theoretical models derived from basic scientific principles, and correlated with severity of exposure conditions and interpreted by means of rationally based theoretical models. The practical implications of the effects of fluids are discussed. The issue of fluid effects on polymers and polymeric composites is of concern to engineers and scientists active in aerospace and naval structures, as an increasing portion of these structures are made of polymeric composites and employ polymeric adhesives as a joining device. While...

  9. Effect of dielectrophoretic structuring on piezoelectric and pyroelectric properties of lead titanate-epoxy composites

    NARCIS (Netherlands)

    Khanbareh, H.; Zwaag, S. van der; Groen, W.A.

    2014-01-01

    Functional granular composites of lead titanate particles in an epoxy matrix prepared by dielectrophoresis show enhanced dielectric, piezoelectric and pyroelectric properties compared to 0-3 composites for different ceramic volume content from 10% to 50%. Two structuring parameters, the

  10. Scarf Repair of Composite Laminates

    Directory of Open Access Journals (Sweden)

    Xie Zonghong

    2016-01-01

    Full Text Available The use of composite materials, such as carbon-fiber reinforced plastic (CFRP composites, aero-structures has led to an increased need of advanced assembly joining and repair technologies. Adhesive bonded repairs as an alternative to recover full or part of initial strength were investigated. Tests were conducted with the objective of evaluating the effectiveness of techniques used for repairing damage fiber reinforced laminated composites. Failure loads and failure modes were generated and compared with the following parameters: scarf angles, roughness of grind tool and number of external plies. Results showed that scarf angle was the critical parameter and the largest tensile strength was observed with the smallest scarf angle. Besides, the use of external plies at the outer surface could not increase the repairs efficiency for large scarf angle. Preparing the repair surfaces by sanding them with a sander ranging from 60 to 100 grit number had significant effect on the failure load. These results allowed the proposal of design principles for repairing CFRP structures.

  11. Tuning Parameters in Heuristics by Using Design of Experiments Methods

    Science.gov (United States)

    Arin, Arif; Rabadi, Ghaith; Unal, Resit

    2010-01-01

    With the growing complexity of today's large scale problems, it has become more difficult to find optimal solutions by using exact mathematical methods. The need to find near-optimal solutions in an acceptable time frame requires heuristic approaches. In many cases, however, most heuristics have several parameters that need to be "tuned" before they can reach good results. The problem then turns into "finding best parameter setting" for the heuristics to solve the problems efficiently and timely. One-Factor-At-a-Time (OFAT) approach for parameter tuning neglects the interactions between parameters. Design of Experiments (DOE) tools can be instead employed to tune the parameters more effectively. In this paper, we seek the best parameter setting for a Genetic Algorithm (GA) to solve the single machine total weighted tardiness problem in which n jobs must be scheduled on a single machine without preemption, and the objective is to minimize the total weighted tardiness. Benchmark instances for the problem are available in the literature. To fine tune the GA parameters in the most efficient way, we compare multiple DOE models including 2-level (2k ) full factorial design, orthogonal array design, central composite design, D-optimal design and signal-to-noise (SIN) ratios. In each DOE method, a mathematical model is created using regression analysis, and solved to obtain the best parameter setting. After verification runs using the tuned parameter setting, the preliminary results for optimal solutions of multiple instances were found efficiently.

  12. Conducting compositions of matter

    Science.gov (United States)

    Viswanathan, Tito (Inventor)

    2000-01-01

    The invention provides conductive compositions of matter, as well as methods for the preparation of the conductive compositions of matter, solutions comprising the conductive compositions of matter, and methods of preparing fibers or fabrics having improved anti-static properties employing the conductive compositions of matter.

  13. Corrosion resistant composite materials

    International Nuclear Information System (INIS)

    Ul'yanin, E.A.

    1986-01-01

    Foundations for corrosion-resistant composite materials design are considered with account of components compatibility. Fibrous and lamellar composites with metal matrix, dispersion-hardened steels and alloys, refractory metal carbides-, borides-, nitrides-, silicides-based composites are described. Cermet compositions and fields of their application, such as protective coatings for operation in agressive media at high temperatures, are presented

  14. Volumetric composition in composites and historical data

    DEFF Research Database (Denmark)

    Lilholt, Hans; Madsen, Bo

    2013-01-01

    The obtainable volumetric composition in composites is of importance for the prediction of mechanical and physical properties, and in particular to assess the best possible (normally the highest) values for these properties. The volumetric model for the composition of (fibrous) composites gives...... guidance to the optimal combination of fibre content, matrix content and porosity content, in order to achieve the best obtainable properties. Several composite materials systems have been shown to be handleable with this model. An extensive series of experimental data for the system of cellulose fibres...... and polymer (resin) was produced in 1942 – 1944, and these data have been (re-)analysed by the volumetric composition model, and the property values for density, stiffness and strength have been evaluated. Good agreement has been obtained and some further observations have been extracted from the analysis....

  15. Parameters in pure type systems

    NARCIS (Netherlands)

    Bloo, C.J.; Kamareddine, F.; Laan, T.D.L.; Nederpelt, R.P.; Rajsbaum, S.

    2002-01-01

    In this paper we study the addition of parameters to typed ¿-calculus with definitions. We show that the resulting systems have nice properties and illustrate that parameters allow for a better fine-tuning of the strength of type systems as well as staying closer to type systems used in practice in

  16. ACTIVATION PARAMETERS AND EXCESS THERMODYANAMIC ...

    African Journals Online (AJOL)

    Applying these data, viscosity-B-coefficients, activation parameters (Δμ10≠) and (Δμ20≠) and excess thermodynamic functions, viz., excess molar volume (VE), excess viscosity, ηE and excess molar free energy of activation of flow, (GE) were calculated. The value of interaction parameter, d, of Grunberg and Nissan ...

  17. HF Parameters of Induction Motor

    Directory of Open Access Journals (Sweden)

    M. N. Benallal

    2017-09-01

    Full Text Available This article describes the results of experimental studies of HF input and primary parameters. A simulation model in Matlab SimulinkTM of multiphase windings as ladder circuit of coils is developed. A method for determining the primary parameters of ladder equivalent circuits is presented.

  18. Estimating deep seafloor interface and volume roughness parameters using the multibeam-hydrosweep system

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, B.; Schenke, H.W.; Kodagali, V.N.; Hagen, R.

    composite roughness model, including water-sediment interface roughness and sediment volume roughness parameters the data was modeled. The model effectively uses the near normal incidence angle backscatter to determine the seafloor interface roughness...

  19. Generating three-parameter sensor

    Directory of Open Access Journals (Sweden)

    Filinyuk M. A.

    2014-08-01

    Full Text Available Generating sensors provide the possibility of getting remote information and its easy conversion into digital form. Typically, these are one-parameter sensors formed by combination of a primary transmitter (PT and a sine wave generator. Two-parameter sensors are not widely used as their implementation causes a problem with ambiguity output when measuring the PT. Nevertheless, the problem of creating miniature, thrifty multi-parameter RF sensors for different branches of science and industry remains relevant. Considering ways of designing RF sensors, we study the possibility of constructing a three-parameter microwave radio frequency range sensor, which is based on a two-stage three-parameter generalized immitance convertor (GIC. Resistive, inductive and capacitive PT are used as sensing elements. A mathematical model of the sensor, which describes the relation of the sensor parameters to the parameters of GIC and PT was developed. The basic parameters of the sensor, its transfer function and sensitivity were studied. It is shown that the maximum value of the power generated signal will be observed at a frequency of 175 MHz, and the frequency ranges depending on the parameters of the PT will be different. Research results and adequacy of the mathematical model were verified by the experiment. Error of the calculated dependences of the lasing frequency on PT parameters change, compared with the experimental data does not exceed 2 %. The relative sensitivity of the sensor based on two-stage GIC showed that for the resistive channel it is about 1.88, for the capacitive channel –1,54 and for the inductive channel –11,5. Thus, it becomes possible to increase the sensor sensitivity compared with the sensitivity of the PT almost 1,2—2 times, and by using the two stage GIC a multifunctional sensor is provided.

  20. Coal ash parameters by neutron activation

    International Nuclear Information System (INIS)

    Chrusciel, Edward; Chau, N.D.; Niewodniczanski, J.W.

    1994-01-01

    The coal parameters, ash content and ash slagging index, may be strongly related to the chemical composition of mineral impurities in coal. Based on this assumption the authors have examined the feasibility of neutron activation techniques, both as a laboratory and a well logging method, by recording induced γ-rays in the two energy intervals with the help of a scintillation γ-ray spectrometer. Results from the Upper Silesiab Coal Basin have shown that the method can be used to evaluate the ash content and ash fusion temperature, both in the laboratory and in well logging; the corresponding mean standard deviations being 1.5 wt% and 35 o C; and 3 wt% and 45 o C respectively. (author)

  1. Stiffened Composite Fuselage Barrel Optimization

    Science.gov (United States)

    Movva, R. G.; Mittal, A.; Agrawal, K.; Upadhyay, C. S.

    2012-07-01

    In a typical commercial transport aircraft, Stiffened skin panels and frames contribute around 40% of the fuselage weight. In the current study a stiffened composite fuselage skin panel optimization engine is developed for optimization of the layups of composite panels and stringers using Genetic Algorithm (GA). The skin and stringers of the fuselage section are optimized for the strength and the stability requirements. The selection of the GA parameters considered for the optimization is arrived by performing case studies on selected problems. The optimization engine facilitates in carrying out trade studies for selection of the optimum ply layup and material combination for the configuration being analyzed. The optimization process is applied on a sample model and the results are presented.

  2. Creep of fibrous composite materials

    DEFF Research Database (Denmark)

    Lilholt, Hans

    1985-01-01

    Models are presented for the creep behaviour of fibrous composite materials with aligned fibres. The models comprise both cases where the fibres remain rigid in a creeping matrix and cases where the fibres are creeping in a creeping matrix. The treatment allows for several contributions...... to the creep strength of composites. The advantage of combined analyses of several data sets is emphasized and illustrated for some experimental data. The analyses show that it is possible to derive creep equations for the (in situ) properties of the fibres. The experiments treated include model systems...... such as Ni + W-fibres, high temperature materials such as Ni + Ni3Al + Cr3C2-fibres, and medium temperature materials such as Al + SiC-fibres. For the first two systems reasonable consistency is found for the models and the experiments, while for the third system too many unquantified parameters exist...

  3. Physical and mechanical properties of unidirectional plant fibre composites

    DEFF Research Database (Denmark)

    Madsen, B.; Lilholt, H.

    2003-01-01

    Unidirectional composites were made from filament wound non-treated flax yarns and polypropylene foils. With increasing composite fibre weight fractions from 0.56 to 0.72, porosity fractions increased from 0.04 to 0.08; a theoretical model was fitted to the data in order to describe the composite...... version of the "rule-of-mixtures", supplemented with parameters of composite porosity content and anisotropy of fibre properties, were developed to improve the prediction of composite tensile properties. (C) 2003 Elsevier Science Ltd. All rights reserved....

  4. Hydrothermal carbonization. Investigation of process parameters

    Energy Technology Data Exchange (ETDEWEB)

    Steinbrueck, J.; Rossbach, M.; Reichert, D.; Bockhorn, H. [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany). Inst. of Technical Chemistry and Polymerchemistry; Walz, L. [Energie Baden-Wuerttemberg AG, Karlsruhe (Germany); Eyler, D. [European Institute for Energy Research, Karlsruhe (Germany)

    2010-07-01

    For energetic use and as a raw material lignocellulosic biomass becomes more and more important. Among pyrolytic refining, the hydrothermal treatment can be an alternative way to deoxygenerate biomass. The objective of this study is to gain deeper insights into the Hydrothermal Carbonization (HTC) process and also to define basic parameters for the construction of a small pilot plant. The biomass is converted in an autoclave at temperatures between 180 C and 240 C establishing the respective vapour pressure. Reaction times between 1 and 12 hours are applied and various catalysts in different concentrations are tested. Elemental analysis of the product, a brown coal-like solid, shows a composition of ca. C{sub 4}H{sub 3}O{sub 1}, corresponding to a carbon recovery of 60% of initial carbon mass. The elemental composition of the product is independent of the process temperature and the applied biomass, if a minimal reaction time is adhered, which however heavily depends on the reaction temperature. The remaining carbon species in intermediate reaction products in the liquid and gas phase are characterised by use of GC/MS, HPLC and FTIR. From the experimental data a two-way mechanism is deduced that includes a rapid formation of an initial solid and dehydration and decomposition reactions which lead to smaller organic molecules, e.g. furfural and aromatic species, and can be promoted by acid catalysis, e.g. H{sub 2}SO{sub 4}. (orig.)

  5. Mechanics of composite materials - 1983. Proceedings of the Symposium, Boston, MA, November 13-18, 1983

    International Nuclear Information System (INIS)

    Dvorak, G.J.

    1983-01-01

    The present conference discusses plate theories applicable to laminated composites, the analysis of large deformations in layered composite shells, composite plate nonlinear bending effects, hybrid composite constitutive behavior, polymeric material life prediction by means of kinetic fracture mechanics, and crack growth direction in fibrous composites. Also discussed are stress singularities and solution structures, together with the delamination behavior and fracture mechanics parameters, of delamination mechanics in fiber-reinforced composites, followed by the theory and applications of unidirectional composite fracture, impact and fatigue behavior in graphite-epoxy laminates, and the fracture behavior of notched unidirectional boron/aluminum composite laminates

  6. Comparison of Parameter Identification Techniques

    Directory of Open Access Journals (Sweden)

    Eder Rafael

    2016-01-01

    Full Text Available Model-based control of mechatronic systems requires excellent knowledge about the physical behavior of each component. For several types of components of a system, e.g. mechanical or electrical ones, the dynamic behavior can be described by means of a mathematic model consisting of a set of differential equations, difference equations and/or algebraic constraint equations. The knowledge of a realistic mathematic model and its parameter values is essential to represent the behaviour of a mechatronic system. Frequently it is hard or impossible to obtain all required values of the model parameters from the producer, so an appropriate parameter estimation technique is required to compute missing parameters. A manifold of parameter identification techniques can be found in the literature, but their suitability depends on the mathematic model. Previous work dealt with the automatic assembly of mathematical models of serial and parallel robots with drives and controllers within the dynamic multibody simulation code HOTINT as fully-fledged mechatronic simulation. Several parameters of such robot models were identified successfully by our embedded algorithm. The present work proposes an improved version of the identification algorithm with higher performance. The quality of the identified parameter values and the computation effort are compared with another standard technique.

  7. Research on structure and electrical parameters of indium antimonide films

    International Nuclear Information System (INIS)

    Mukhametniyazova, A.; Konyaeva, V.F.; Sukhanov, S.; Ashirov, A.; Aleksanyan, S.N.

    1980-01-01

    Results of investigations into the effect of conditions of formation of indium antimonide films prepared by thermal vacuum spraying on their structure, phase composition and electric parameters, are presented. The method of studying the synthesized semiconductor layers on the DRON-0.5 X-ray device with CoKsub(α)-radiation is tested. The dependence of structure, phase composition and electric properties of InSb layers 1+3 μm thick sprayed on ferrite substrates on condensation temperature, is established. Hexagonal InSb modification is found

  8. Research on structure and electrical parameters of indium antimonide films

    Energy Technology Data Exchange (ETDEWEB)

    Mukhametniyazova, A; Konyaeva, V F; Sukhanov, S; Ashirov, A; Aleksanyan, S N [AN Turkmenskoj SSR, Ashkhabad. Fiziko-Tekhnicheskii Inst.

    1980-01-01

    Results of investigations into the effect of conditions of formation of indium antimonide films prepared by thermal vacuum spraying on their structure, phase composition and electric parameters, are presented. The method of studying the synthesized semiconductor layers on the DRON-0.5 X-ray device with CoKsub(..cap alpha..)-radiation is tested. The dependence of structure, phase composition and electric properties of InSb layers 1+3 ..mu..m thick sprayed on ferrite substrates on condensation temperature, is established. Hexagonal InSb modification is found.

  9. Matrix densification of SiC composites by sintering process

    International Nuclear Information System (INIS)

    Kim, Young-Wook; Jang, Doo-Hee; Eom, Jung-Hye; Chun, Yong-Seong

    2007-02-01

    The objectives of this research are to develop a process for dense SiC fiber-SiC composites with a porosity of 5% or less and to develop high-strength SiC fiber-SiC composites with a strength of 500 MPa or higher. To meet the above objectives, the following research topics were investigated ; new process development for the densification of SiC fiber-SiC composites, effect of processing parameters on densification of SiC fiber-SiC composites, effect of additive composition on matrix microstructure, effects of additive composition and content on densification of SiC fiber-SiC composites, mechanical properties of SiC fiber-SiC composites, effect of fiber coating on densification and strength of SiC fiber-SiC composites, development of new additive composition. There has been a great deal of progress in the development of technologies for the processing and densification of SiC fiber-SiC composites and in better understanding of additive-densification-mechanical property relations as results of this project. Based on the progress, dense SiC fiber-SiC composites (≥97%) and high strength SiC fiber-SiC composites (≥600 MPa) have been developed. Development of 2D SiC fiber-SiC composites with a relative density of ≥97% and a strength of ≥600 MPa can be counted as a notable achievement

  10. Telemetry System of Biological Parameters

    Directory of Open Access Journals (Sweden)

    Jan Spisak

    2005-01-01

    Full Text Available The mobile telemetry system of biological parameters serves for reading and wireless data transfer of measured values of selected biological parameters to an outlying computer. It concerns basically long time monitoring of vital function of car pilot.The goal of this projects is to propose mobile telemetry system for reading, wireless transfer and processing of biological parameters of car pilot during physical and psychical stress. It has to be made with respect to minimal consumption, weight and maximal device mobility. This system has to eliminate signal noise, which is created by biological artifacts and disturbances during the data transfer.

  11. Atmospheric Data Package for the Composite Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Napier, Bruce A.; Ramsdell, James V.

    2005-09-01

    The purpose of this data package is to summarize our conceptual understanding of atmospheric transport and deposition, describe how this understanding will be simplified for numerical simulation as part of the Composite Analysis (i.e., implementation model), and finally to provide the input parameters needed for the simulations.

  12. Evaluation of water balance parameters from isotopic measurements in evaporation pans

    International Nuclear Information System (INIS)

    Allison, G.B.

    1979-01-01

    The evaluation of the parameters governing the isotopic composition of evaporating water bodies was attempted by means of evaporation pans. The instability of the meteorological conditions, however, makes it virtually impossible to evaluate the atmospheric relative humidity and its isotopic composition with pans. Pans are only suitable to obtain seasonal trends of the isotopic composition of the net evaporated water. For this, a technique based on two pans is also proposed. (author)

  13. Optimal Design of Shock Tube Experiments for Parameter Inference

    KAUST Repository

    Bisetti, Fabrizio

    2014-01-06

    We develop a Bayesian framework for the optimal experimental design of the shock tube experiments which are being carried out at the KAUST Clean Combustion Research Center. The unknown parameters are the pre-exponential parameters and the activation energies in the reaction rate expressions. The control parameters are the initial mixture composition and the temperature. The approach is based on first building a polynomial based surrogate model for the observables relevant to the shock tube experiments. Based on these surrogates, a novel MAP based approach is used to estimate the expected information gain in the proposed experiments, and to select the best experimental set-ups yielding the optimal expected information gains. The validity of the approach is tested using synthetic data generated by sampling the PC surrogate. We finally outline a methodology for validation using actual laboratory experiments, and extending experimental design methodology to the cases where the control parameters are noisy.

  14. Rewetting of composite slab

    International Nuclear Information System (INIS)

    Satapathy, A.K.; Singh, K.C.

    1996-01-01

    The process of re-establishment of wetting of hot surface is of practical importance in chemical, metallurgical and nuclear industries. Rewetting is considered in emergency core cooling in nuclear reactors in the event of postulated loss of coolant accident (LOCA). This paper deals with numerical solution of the two-dimensional quasi-static conduction controlled rewetting of an infinite parallel sided composite slab assuming perfect contact is maintained at the interface. On the wetted side upstream of the quench front, a constant heat transfer coefficient is assumed. The downstream of quench front and unwetted side of slab are supposed to be adiabatic. The solution gives the quench front temperature as a function of various model parameters such as Peclet number, wet side Blot number, dimensionless thickness of slab and cladding to fuel ratio of thermal conductivities. The results show that for large values of rewetting velocities, the dimensionless rewetting temperature is unaffected by fuel properties for all values of Blot numbers. (author). 7 refs., 2 tabs., 1 fig

  15. Composite waste analysis system

    International Nuclear Information System (INIS)

    Wachter, J.R.; Hagan, R.C.; Bonner, C.A.; Malcom, J.E.; Camp, K.L.

    1993-01-01

    Nondestructive analysis (NDA) of radioactive waste forms an integral component of nuclear materials accountability programs and waste characterization acceptance criterion. However, waste measurements are often complicated by unknown isotopic compositions and the potential for concealment of special nuclear materials in a manner that is transparent to gamma-ray measurement instruments. To overcome these complications, a new NDA measurement system has been developed to assay special nuclear material in both transuranic and low level waste from the same measurement platform. The system incorporates a NaI detector and customized commercial software routines to measure small quantities of radioactive material in low level waste. Transuranic waste analysis is performed with a coaxial HPGE detector and uses upgraded PC-based segmented gamma scanner software to assay containers up to 55 gal. in volume. Gamma-Ray isotopics analysis of both waste forms is also performed with this detector. Finally, a small neutron counter using specialized software is attached to the measurement platform to satisfy safeguards concerns related to nuclear materials that are not sensed by the gamma-ray instruments. This report describes important features and capabilities of the system and presents a series of test measurements that are to be performed to define system parameters

  16. Composite Differential Search Algorithm

    Directory of Open Access Journals (Sweden)

    Bo Liu

    2014-01-01

    Full Text Available Differential search algorithm (DS is a relatively new evolutionary algorithm inspired by the Brownian-like random-walk movement which is used by an organism to migrate. It has been verified to be more effective than ABC, JDE, JADE, SADE, EPSDE, GSA, PSO2011, and CMA-ES. In this paper, we propose four improved solution search algorithms, namely “DS/rand/1,” “DS/rand/2,” “DS/current to rand/1,” and “DS/current to rand/2” to search the new space and enhance the convergence rate for the global optimization problem. In order to verify the performance of different solution search methods, 23 benchmark functions are employed. Experimental results indicate that the proposed algorithm performs better than, or at least comparable to, the original algorithm when considering the quality of the solution obtained. However, these schemes cannot still achieve the best solution for all functions. In order to further enhance the convergence rate and the diversity of the algorithm, a composite differential search algorithm (CDS is proposed in this paper. This new algorithm combines three new proposed search schemes including “DS/rand/1,” “DS/rand/2,” and “DS/current to rand/1” with three control parameters using a random method to generate the offspring. Experiment results show that CDS has a faster convergence rate and better search ability based on the 23 benchmark functions.

  17. Biotropic parameters of magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Shishlo, M.A.

    The use of magnetic fields (MF) in biology and medicine to control biological systems has led to appearance of the term, biotropic parameters of MF. They include the physical characteristics of MF, which determine the primary biologically significant physicochemical mechanisms of field action causing formation of corresponding reactions on the level of the integral organism. These parameters include MF intensity, gradient, vector, pulse frequency and shape, and duration of exposure. Factors that elicit responses by the biological system include such parameter of MF interaction with the integral organism as localization of exposure and volume of tissues interacting with the field, as well as the initial state of the organism. In essence, the findings of experimental studies of biotropic parameters of MF make it possible to control physiological processes and will aid in optimizing methods of MF therapy.

  18. Parameters of care for craniosynostosis

    DEFF Research Database (Denmark)

    Vargervik, Karin; Rubin, Marcie S; Grayson, Barry H

    2012-01-01

    A multidisciplinary conference was convened in March 2010 with the charge to develop parameters of care for patients with craniosynostosis. The 52 participants represented 16 medical specialties and 16 professional societies. Herein, we present the dental, orthodontic, and surgical care...

  19. Real-Time Parameter Identification

    Data.gov (United States)

    National Aeronautics and Space Administration — Armstrong researchers have implemented in the control room a technique for estimating in real time the aerodynamic parameters that describe the stability and control...

  20. THE HAEMORHEOLOGICAL PARAMETERS OF HYPERTENSIVE ...

    African Journals Online (AJOL)

    admin

    ) and. Whole Blood Relative Viscosity (WBRV) were determined by capillary viscometry as described by Reid and Ugwu (1987) and recently modified by Korubo-Owiye et al. (1997). All haemorheological parameters were analyzed within 2 ...

  1. Material parameters for thermoelectric performance

    Indian Academy of Sciences (India)

    The thermoelectric performance of a thermoelement is ideally defined in terms of the so-called ... However, there are other parameters which are fairly good indicators ... Whereas a final deciding factor reflecting on .... matter of a future work.

  2. Inflation and cosmological parameter estimation

    Energy Technology Data Exchange (ETDEWEB)

    Hamann, J.

    2007-05-15

    In this work, we focus on two aspects of cosmological data analysis: inference of parameter values and the search for new effects in the inflationary sector. Constraints on cosmological parameters are commonly derived under the assumption of a minimal model. We point out that this procedure systematically underestimates errors and possibly biases estimates, due to overly restrictive assumptions. In a more conservative approach, we analyse cosmological data using a more general eleven-parameter model. We find that regions of the parameter space that were previously thought ruled out are still compatible with the data; the bounds on individual parameters are relaxed by up to a factor of two, compared to the results for the minimal six-parameter model. Moreover, we analyse a class of inflation models, in which the slow roll conditions are briefly violated, due to a step in the potential. We show that the presence of a step generically leads to an oscillating spectrum and perform a fit to CMB and galaxy clustering data. We do not find conclusive evidence for a step in the potential and derive strong bounds on quantities that parameterise the step. (orig.)

  3. Reduction of robot base parameters

    Energy Technology Data Exchange (ETDEWEB)

    Vandanjon, P O [CEA Centre d` Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. des Procedes et Systemes Avances; Gautier, M [Nantes Univ., 44 (France)

    1996-12-31

    This paper is a new step in the search of minimum dynamic parameters of robots. In spite of planing exciting trajectories and using base parameters, some parameters remain not identifiable due to the perturbation effects. In this paper, we propose methods to reduce the set of base parameters in order to get an essential set of parameters. This new set defines a simplified identification model witch improves the noise immunity of the estimation process. It contributes also in reducing the computation burden of a simplified dynamic model. Different methods are proposed and are classified in two parts: methods, witch perform reduction and identification together, come from statistical field and methods, witch reduces the model before the identification thanks to a priori information, come from numerical field like the QR factorization. Statistical tools and QR reduction are shown to be efficient and adapted to determine the essential parameters. They can be applied to open-loop, or graph structured rigid robot, as well as flexible-link robot. Application for the PUMA 560 robot is given. (authors). 9 refs., 4 tabs.

  4. Reduction of robot base parameters

    International Nuclear Information System (INIS)

    Vandanjon, P.O.

    1995-01-01

    This paper is a new step in the search of minimum dynamic parameters of robots. In spite of planing exciting trajectories and using base parameters, some parameters remain not identifiable due to the perturbation effects. In this paper, we propose methods to reduce the set of base parameters in order to get an essential set of parameters. This new set defines a simplified identification model witch improves the noise immunity of the estimation process. It contributes also in reducing the computation burden of a simplified dynamic model. Different methods are proposed and are classified in two parts: methods, witch perform reduction and identification together, come from statistical field and methods, witch reduces the model before the identification thanks to a priori information, come from numerical field like the QR factorization. Statistical tools and QR reduction are shown to be efficient and adapted to determine the essential parameters. They can be applied to open-loop, or graph structured rigid robot, as well as flexible-link robot. Application for the PUMA 560 robot is given. (authors). 9 refs., 4 tabs

  5. Compositional Advantage and Strategy

    DEFF Research Database (Denmark)

    Li, Xin

    advantage is redefined as the attractiveness of the composition of the producer’s offering in terms of scope and perceived value/price ratio. I identify five ways or basic compositional strategies to improve the value/price ratio. A firm may have an overall compositional strategy that is composed of some......In this paper, I first critique the composition-based view of Yadong Luo and John Child for understanding how resource-poor firms survive and thrive. To remedy the deficiencies in their perspective, I then propose a dynamic theory of compositional advantage and strategy. Here, the compositional...... or all of the five basic compositional strategies. I argue there are three indispensable key success factors for a composition-based competition, i.e., aspiration (ambition-position asymmetry), attitude (being ALERT), and action (turning asymmetry into advantage). I also discuss the particular relevance...

  6. Conductive polypropylene composites

    International Nuclear Information System (INIS)

    Koszkul, J.

    1997-01-01

    The results of studies on polypropylene composites with three sorts of Polish-made carbon blacks were presented. It was found that composite of 20% black content had properties of an electrically conducting material

  7. Radiation curable adhesive compositions and composite structures

    International Nuclear Information System (INIS)

    Brenner, W.

    1984-01-01

    This disclosure relates to novel adhesive compositions and composite structures utilizing the same, wherein said adhesive compositions contain an elastomer, a chemically compatible ethylenically unsaturated monomer, a tackifier, an adhesion promoter, and optionally, pigments, fillers, thickeners and flow control agents which are converted from the liquid to the solid state by exposure to high energy ionizing radiation such as electron beam. A particularly useful application for such adhesive compositions comprises the assembly of certain composite structures or laminates consisting of, for example, a fiber flocked rubber sheet and a metal base with the adhesive fulfilling the multiple functions of adhering the flocked fiber to the rubber sheet as well as adhering the rubber sheet to the metal base. Optionally, the rubber sheet itself may also be cured at the same time as the adhesive composition with all operations being carried out at ambient temperatures and in the presence of air, with exposure of said assembly to selected dosages of high energy ionizing radiation. These adhesive compositions contain no solvents thereby almost eliminating air pollution or solvent toxicity problems, and offer substantial savings in energy and labor as they are capable of curing in very short time periods without the use of external heat which might damage the substrate

  8. Nano-composite materials

    Science.gov (United States)

    Lee, Se-Hee; Tracy, C. Edwin; Pitts, J. Roland

    2010-05-25

    Nano-composite materials are disclosed. An exemplary method of producing a nano-composite material may comprise co-sputtering a transition metal and a refractory metal in a reactive atmosphere. The method may also comprise co-depositing a transition metal and a refractory metal composite structure on a substrate. The method may further comprise thermally annealing the deposited transition metal and refractory metal composite structure in a reactive atmosphere.

  9. Amorphous metal composites

    International Nuclear Information System (INIS)

    Byrne, M.A.; Lupinski, J.H.

    1984-01-01

    This patent discloses an improved amorphous metal composite and process of making the composite. The amorphous metal composite comprises amorphous metal (e.g. iron) and a low molecular weight thermosetting polymer binder. The process comprises placing an amorphous metal in particulate form and a thermosetting polymer binder powder into a container, mixing these materials, and applying heat and pressure to convert the mixture into an amorphous metal composite

  10. Two-boson composites

    DEFF Research Database (Denmark)

    Tichy, Malte C.; Bouvrier, P. Alexander; Mølmer, Klaus

    2013-01-01

    Composite bosons made of two bosonic constituents exhibit deviations from ideal bosonic behavior due to their substructure. This deviation is reflected by the normalization ratio of the quantum state of N composites. We find a set of saturable, efficiently evaluable bounds for this indicator, which...... quantifies the bosonic behavior of composites via the entanglement of their constituents. We predict an abrupt transition between ordinary and exaggerated bosonic behavior in a condensate of two-boson composites....

  11. Infiltrated carbon foam composites

    Science.gov (United States)

    Lucas, Rick D. (Inventor); Danford, Harry E. (Inventor); Plucinski, Janusz W. (Inventor); Merriman, Douglas J. (Inventor); Blacker, Jesse M. (Inventor)

    2012-01-01

    An infiltrated carbon foam composite and method for making the composite is described. The infiltrated carbon foam composite may include a carbonized carbon aerogel in cells of a carbon foam body and a resin is infiltrated into the carbon foam body filling the cells of the carbon foam body and spaces around the carbonized carbon aerogel. The infiltrated carbon foam composites may be useful for mid-density ablative thermal protection systems.

  12. Advanced composites for windmills

    Science.gov (United States)

    Bourquardez, G.

    A development status assessment is conducted for advanced composite construction techniques for windmill blade structures which, as in the case of composite helicopter rotors, promise greater reliability, longer service life, superior performance, and lower costs. Composites in wind turbine applications must bear aerodynamic, inertial and gravitational loads in complex interaction cycles. Attention is given to large Darrieus-type vertical axis windmills, to which composite construction methods may offer highly effective pitch-control mechanisms, especially in the 'umbrella' configuration.

  13. Exotic composite vector boson

    International Nuclear Information System (INIS)

    Akama, K.; Hattori, T.; Yasue, M.

    1991-01-01

    An exotic composite vector boson V is introduced in two dynamical models of composite quarks, leptons, W, and Z. One is based on four-Fermi interactions, in which composite vector bosons are regarded as fermion-antifermion bound states and the other is based on the confining SU(2) L gauge model, in which they are given by scalar-antiscalar bound states. Both approaches describe the same effective interactions for the sector of composite quarks, leptons, W, Z, γ, and V

  14. Statistical approach for uncertainty quantification of experimental modal model parameters

    DEFF Research Database (Denmark)

    Luczak, M.; Peeters, B.; Kahsin, M.

    2014-01-01

    Composite materials are widely used in manufacture of aerospace and wind energy structural components. These load carrying structures are subjected to dynamic time-varying loading conditions. Robust structural dynamics identification procedure impose tight constraints on the quality of modal models...... represent different complexity levels ranging from coupon, through sub-component up to fully assembled aerospace and wind energy structural components made of composite materials. The proposed method is demonstrated on two application cases of a small and large wind turbine blade........ This paper aims at a systematic approach for uncertainty quantification of the parameters of the modal models estimated from experimentally obtained data. Statistical analysis of modal parameters is implemented to derive an assessment of the entire modal model uncertainty measure. Investigated structures...

  15. Microwave Measurements of Ferrite Polymer Composite Materials

    Directory of Open Access Journals (Sweden)

    Rastislav Dosoudil

    2004-01-01

    Full Text Available The article focuses on the microwave measurements performed on the nickel-zinc sintered ferrite with the chemical formula Ni0.3Zn0.7Fe2O4 produced by the ceramic technique and composite materials based on this ferrite and a non-magnetic polymer (polyvinyl chloride matrix. The prepared composite samples had the same particle size distribution 0-250um but different ferrite particle concentrations between 23 vol% and 80 vol%. The apparatus for measurement of the signal proportional to the absolute value of scattering parameter S11 (reflexion coefficient is described and the dependence of measured reflected signal on a bias magnetic field has been studied. By means of experiments, the resonances to be connected with the geometry of microwave experimental set-up were distinguished from ferromagnetic resonance arising in ferrite particles of composite structure. The role of local interaction fields of ferrite particles in composite material has been discussed.

  16. Evaluating interfacial shear stresses in composite hollo

    Directory of Open Access Journals (Sweden)

    Aiham Adawi

    2016-09-01

    Full Text Available Analytical evaluation of the interfacial shear stresses for composite hollowcore slabs with concrete topping is rare in the literature. Adawi et al. (2014 estimated the interfacial shear stiffness coefficient (ks that governs the behavior of the interface between hollowcore slabs and the concrete topping using push-off tests. This parameter is utilized in this paper to provide closed form solutions for the differential equations governing the behavior of simply supported composite hollowcore slabs. An analytical solution based on the deformation compatibility of the composite section and elastic beam theory, is developed to evaluate the shear stresses along the interface. Linear finite element modeling of the full-scale tests presented in Adawi et al. (2015 is also conducted to validate the developed analytical solution. The proposed analytical solution was found to be adequate in estimating the magnitude of horizontal shear stress in the studied composite hollowcore slabs.

  17. Flexural creep behaviour of jute polypropylene composites

    Science.gov (United States)

    Chandekar, Harichandra; Chaudhari, Vikas

    2016-09-01

    Present study is about the flexural creep behaviour of jute fabric reinforced polypropylene (Jute-PP) composites. The PP sheet and alkali treated jute fabric is stacked alternately and hot pressed in compression molding machine to get Jute-PP composite laminate. The flexural creep study is carried out on dynamic mechanical analyzer. The creep behaviour of the composite is modeled using four-parameter Burgers model. Short-term accelerated creep testing is conducted which is later used to predict long term creep behaviour. The feasibility of the construction of a master curve using the time-temperature superposition (TTS) principle to predict long term creep behavior of unreinforced PP and Jute-PP composite is investigated.

  18. Explosive composition containing water

    Energy Technology Data Exchange (ETDEWEB)

    Cattermole, G.R.; Lyerly, W.M.; Cummings, A.M.

    1971-11-26

    This addition to Fr. 1,583,223, issued 31 May 1968, describes an explosive composition containing a water in oil emulsion. The composition contains an oxidizing mineral salt, a nitrate base salt as sensitizer, water, an organic fuel, a lipophilic emulsifier, and incorporates gas bubbles. The composition has a performance which is improved over and above the original patent.

  19. Composition: Unity - Diversity series

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    2015-01-01

    Unity-Diversity series are open compositions to be realised by improvising musicians. See more about my composition practise in the entry "Composition - General Introduction". This work is licensed under a Creative Commons "by-nc" License. You may for non-commercial purposes use and distribute it...

  20. Adhesive compositions and methods

    Science.gov (United States)

    Allen, Scott D.; Sendijarevic, Vahid; O'Connor, James

    2017-12-05

    The present invention encompasses polyurethane adhesive compositions comprising aliphatic polycarbonate chains. In one aspect, the present invention encompasses polyurethane adhesives derived from aliphatic polycarbonate polyols and polyisocyanates wherein the polyol chains contain a primary repeating unit having a structure:. In another aspect, the invention provides articles comprising the inventive polyurethane compositions as well as methods of making such compositions.