The influence of the mechanical properties on fuel rod support characteristics – A case study of dual cooled fuel

International Nuclear Information System (INIS)

Kim, Jae Yong; Kim, Hyung Kyu; Ko, Sung Ho

2014-01-01

Highlights: • Spring characterization test and analysis were performed to obtain characteristic curves of modified H-type spring. • Using an actual mechanical property is needed to correctly predict the spring characteristics. • The characteristics during unloading should be used for a spacer grid support design. - Abstract: This paper concerns a finite element analysis for a spacer grid support (spring and dimple) design. An accurate prediction of the support characteristics (contact force vs. deflection) is the most crucial in the design by analysis. It is found that the mechanical properties are the key parameter to simulate the characteristics as close as the experimental results after using three different sets of mechanical property data including the actual tensile test results of the present material for a spacer grid of a dual cooled fuel. Besides, the validity of using the characteristics during unloading process is also discussed incorporating a possible overshoot of the support. The coincidence between the present finite element prediction and experimental results is quite good: less than 3.09% at most

Properties of spatial Cox process models

DEFF Research Database (Denmark)

Møller, Jesper

Probabilistic properties of Cox processes of relevance for statistical modelling and inference are studied. Particularly, we study the most important classes of Cox processes, including log Gaussian Cox processes, shot noise Cox processes, and permanent Cox processes. We consider moment properties...... and point process operations such as thinning, displacements, and superpositioning. We also discuss how to simulate specific Cox processes....

Photoelectric properties of ZnO/Ag2S heterostructure and its photoelectric ethanol sensing characteristics

International Nuclear Information System (INIS)

Zhang Yu; Liu Bingkun; Wang Dejun; Lin Yanhong; Xie Tengfeng; Zhai Jiali

2012-01-01

Highlights: ► The ZnO/Ag 2 S heterostructure shows good photoelectric properties under visible-light irradiation. ► Transient photovoltage results reveal the separation process of photo-generated charges and give further evidence of interfacial effects. ► Photoelectric ethanol sensing characteristics have been found for the ZnO/Ag 2 S heterostructure at room temperature. - Abstract: The photoelectric properties of ZnO microspheres, ZnO/Ag 2 S heterogeneous microspheres and Ag 2 S hollow microspheres were investigated systematically by surface photovoltage, transient photovoltage and surface photocurrent techniques. The ZnO/Ag 2 S heterostructure shows superior photoelectric properties in visible-light region compared with pure Ag 2 S. Transient photovoltage results reveal the separation processes of photo-generated charge carriers in the samples. The photoelectric ethanol sensing property induced by visible light for the ZnO/Ag 2 S heterostructure has been found, which should be valuable for the practical application of semiconductor gas sensors at room temperature.

The mechanical properties and hydration characteristics of cement pastes containing added-calcium coal gangue

Energy Technology Data Exchange (ETDEWEB)

Dongxu Li; Xuyan Song [Nanjing University of Technology, Nanjing (China). College of Material Science and Engineering

2008-04-15

The mechanical properties of several kinds of coal gangue calcined with limestone were researched so as to find the optimum way of calcinations with limestone. The microstructure and property of hydration process of cement pastes containing added-calcium coal gangue were analyzed by means of scanning electron microscope (SEM) and the method of mercury in trusion poremeasurement. When the proper amounst of gypsum and fluorite were taken as mineralizers in the course of calcinations of added-calcium coal gangue, the activity of coal gangue can be effectively improved. The results of mechanical property and structural characteristics such as hydration, hydration products and microstructure etc. of cement pastes containing added-calcium coal gangue are consistent.

Analysis of angular momentum properties of photons emitted in fundamental atomic processes

Science.gov (United States)

Zaytsev, V. A.; Surzhykov, A. S.; Shabaev, V. M.; Stöhlker, Th.

2018-04-01

Many atomic processes result in the emission of photons. Analysis of the properties of emitted photons, such as energy and angular distribution as well as polarization, is regarded as a powerful tool for gaining more insight into the physics of corresponding processes. Another characteristic of light is the projection of its angular momentum upon propagation direction. This property has attracted a special attention over the past decades due to studies of twisted (or vortex) light beams. Measurements being sensitive to this projection may provide valuable information about the role of angular momentum in the fundamental atomic processes. Here we describe a simple theoretical method for determination of the angular momentum properties of the photons emitted in various atomic processes. This method is based on the evaluation of expectation value of the total angular momentum projection operator. To illustrate the method, we apply it to the textbook examples of plane-wave, spherical-wave, and Bessel light. Moreover, we investigate the projection of angular momentum for the photons emitted in the process of the radiative recombination with ionic targets. It is found that the recombination photons do carry a nonzero projection of the orbital angular momentum.

Drying characteristics and engineering properties of fermented ...

African Journals Online (AJOL)

STORAGESEVER

2009-03-06

Mar 6, 2009 ... fermented ground cassava. J. T. Nwabanne ... The drying characteristics of fermented ground local variety of ... effect of variety on the drying and engineering properties of fermented .... Figure 2 shows that the bulk density of each cultivar ... very close thermal conductivities as depicted in the shape of Figure ...

Properties and characteristics of high-level waste glass

International Nuclear Information System (INIS)

Ross, W.A.

1977-01-01

This paper has briefly reviewed many of the characteristics and properties of high-level waste glasses. From this review, it can be noted that glass has many desirable properties for solidification of high-level wastes. The most important of these include: (1) its low leach rate; (2) the ability to tolerate large changes in waste composition; (3) the tolerance of anticipated storage temperatures; (4) its low surface area even after thermal shock or impact

Surface energy characteristics of zeolite embedded PVDF nanofiber films with electrospinning process

Science.gov (United States)

Kang, Dong Hee; Kang, Hyun Wook

2016-11-01

Electrospinning is a nano-scale fiber production method with various polymer materials. This technique allows simple fiber diameters control by changing the physical conditions such as applied voltage and polymer solution viscosity during the fabrication process. The electrospun polymer fibers form a thin porous film with high surface area to volume ratio. Due to these unique characteristics, it is widely used for many application fields such as photocatalyst, electric sensor, and antibacterial scaffold for tissue engineering. Filtration is one of the main applications of electrospun polymer fibers for specific application of filtering out dust particles and dehumidification. Most polymers which are commonly used in electrospinning are hard to perform the filtering and dehumidification simultaneously because of their low hygroscopic property. To overcome this obstacle, the desiccant polymers are developed such as polyacrylic acid and polysulfobetaine methacrylate. However, the desiccant polymers are generally expensive and need special solvent for electrospinning. An alternating way to solve these problems is mixing desiccant material like zeolite in polymer solution during an electrospinning process. In this study, the free surface energy characteristics of electrospun polyvinylidene fluoride (PVDF) film with various zeolite concentrations are investigated to control the hygroscopic property of general polymers. Fundamental physical property of wettability with PVDF shows hydrophobicity. The electrospun PVDF film with small weight ratio with higher than 0.1% of zeolite powder shows diminished contact angles that certifying the wettability of PVDF can be controlled using desiccant material in electrospinning process. To quantify the surface energy of electrospun PVDF films, sessile water droplets are introduced on the electrospun PVDF film surface and the contact angles are measured. The contact angles of PVDF film are 140° for without zeolite and 80° for with 5

The Effect of Rheological Properties of Foods on Bolus Characteristics After Mastication

Science.gov (United States)

Hwang, Junah; Bae, Jung Hyun; Kang, Si Hyun; Seo, Kyung Mook; Kim, Byong Ki; Lee, Sook Young

2012-01-01

Objective To evaluate the effects of physical properties of foods on the changes of viscosity and mass as well as the particle size distribution after mastication. Method Twenty subjects with no masticatory disorders were recruited. Six grams of four solid foods of different textures (banana, tofu, cooked-rice, cookie) were provided, and the viscosity and mass after 10, 20, and 30 cycles of mastication and just before swallowing were measured. The physical properties of foods, such as hardness, cohesiveness, and adhesiveness, were measured with a texture analyzer. Wet sieving and laser diffraction were used to determine the distribution of food particle size. Results When we measured the physical characteristics of foods, the cookie was the hardest food, and the banana exhibited marked adhesiveness. Tofu and cooked-rice exhibited a highly cohesive nature. As the number of mastication cycles increased, the masses of all foods were significantly increased (pmastication (pmastication process and food bolus formation were affected by the physical properties of the food. PMID:23342309

[Study on characteristics of pharmacological effects of traditional Chinese medicines distributing along lung meridian based on medicinal property combination].

Science.gov (United States)

Gu, Hao; Zhang, Yan-Ling; Wang, Yun; Qiao, Yan-Jiang

2014-07-01

Medicinal properties are the basic attribute of traditional Chinese medicines (TCM), while the medicinal property theory is the core theoretical foundation of TCM formula combination. In this particle, authors studied the characteristics of pharmacological effects of property combination of traditional Chinese medicines distributing along meridians, with the aim to introduce the medicinal property combination regularity into the design and optimization process of compound TCMs, and bring the medicinal property theory into full play in guiding the formula combination. In this paper, TCMs distributing along "the lung meridian" was taken for example. The medicinal property combinations of TCMs distributing along "the lung meridian" recorded in Pharmacopeia (2010) was collected and processed. Besides, Chinese journal full-text database (CNKI) was used to collect all of pharmacological study literatures concerning the above TCMs that have been published since 1980. The pharmacological information was also supplemented by reference to Science of Chinese Materia Medica and Clinical Science of Chinese Materia Medica. TCMs distributing along the lung meridian with different properties and tastes showed significant differences in pharmacological effects. For example, mild-sweet-lung medicines could lower blood sugar levels, decrease anoxia and enhance immunity; Mild-bitter-lung medicines showed anti-bacterial, anti-hypertension, anti-oxidation effects; Hot-sweet-lung medicines showed antibechic and anti-bacterial effects. And Hot-bitter-lung medicines showed phlegm eliminating and anti-inflammatory effects. Meanwhile, TCMs distributing along the lung meridian had similar pharmacological characteristics, such as anti-bacterial and anti-inflammatory effects, which is consistent with lung's feature in susceptibility to exogenous pathogenic factors. In this study, authors discovered pharmacological characteristics of different TCMs distributing along the lung meridian, which

Microstructure characteristics and effect of aging process on the mechanical properties of squeeze-cast AZ91 alloy

International Nuclear Information System (INIS)

Han, G.M.; Han, Z.Q.; Luo, A.A.; Liu, B.C.

2015-01-01

Highlights: • Characterization of three-dimensional morphologies of precipitates using AFM. • Quantitative microstructure of aged squeeze-cast AZ91 alloy. • The non-uniform continuous precipitation during aging of squeeze-cast AZ91 alloy. • The relationship between microstructure and property of aged squeeze-cast AZ91 alloy. - Abstract: Quantitative microstructure information is critical to modeling and prediction of mechanical properties of structural components. In this study, the microstructure characteristics of aged squeeze-cast AZ91 alloy were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM) analyses. Particularly, a study of the three-dimensional morphology of continuous precipitation during heat treatment was carried out using a combination of TEM and AFM. The results showed that a typical precipitate consisted of three kinds of faces, namely, broad, side, and end faces. The precipitate also presented a lath-shaped morphology with lozenge ends. Combined SEM and TEM analyses revealed quantitative information on the sizes and area number densities of precipitates after aging at different temperatures with different times. In general, the length and width of precipitates increased more rapidly than thickness during aging. The area number density initially increased and then slowly decreased because of coarsening. Furthermore, a special microstructure characteristic of the non-uniform continuous precipitation during aging was investigated using electron probe microanalysis (EPMA). The relationship between hardness response and yield strength was established

Bread making properties of wheat flour supplemented with thermally processed hypoallergenic lupine flour

Energy Technology Data Exchange (ETDEWEB)

Guillamon, E.; Cuadrado, C.; Pedrosa, M. M.; Varela, A.; Cabellos, B.

2010-07-01

In recent years there has been increased interest in using lupine for human nutrition due to its nutritional properties and health benefits. Moreover, lupine is used as an ingredient in bread making because of its functional and technological properties. However, a higher number of allergic reactions to this legume have recently been reported as a consequence of a more widespread consumption of lupine-based foods. In a previous study, several thermal treatments were applied to lupine seeds and flours resulting in reduced allergenicity. In order to study how this thermal processing (autoclaving and boiling) affects the bread making properties, raw and thermally processed lupine flours were used to replace 10% of wheat flour. The effect of supplementing wheat flour with lupine flour on physical dough properties, bread structure and sensory characteristics were analysed. The results indicated that thermally-treated lupine flours, had similar bread making and sensorial properties as untreated lupine flour. These thermal treatments could increase the potential use of lupine flour as a food ingredient while reducing the risk to provoke allergic reactions. (Author) 36 refs.

Oenological and Quality Characteristic on Young White Wines (Sauvignon Blanc: Effects of High Hydrostatic Pressure Processing

Directory of Open Access Journals (Sweden)

Vilbett Briones-Labarca

2017-01-01

Full Text Available High hydrostatic pressure (HHP has shown to have an effect of enhancing some properties without detrimental effects on important quality characteristics, such as colour, pH, and turbidity. This suggests that this technique can be used as an alternative to the existing methods used in wine industry processing. The aim of this study was to investigate the effects of HHP on aroma compounds and also sensory and quality properties of young white wine. HHP treatment did not influence physicochemical parameters, total phenols, and flavonoid contents of white wine; however, the results from analysis of wine indicate that there was a great variation in the concentration of free and total sulphur dioxide (SO2 values and antioxidant capacity of white wine after HHP application. The sensory attributes, such as taste, odour, and overall quality, were not affected by HHP processing at 300 MPa. The chromatic characteristics changed slightly after applying HHP, but these changes could not be visually perceived because they were less than 5%. The use of this technique has the potential to decrease the amount of SO2 added to raw grapes thus maintaining the same properties found in untreated wine. This study provided valuable insights into the biochemical and sensory composition of commercial white wine and how this might change during HHP processing.

Characteristic time scales for diffusion processes through layers and across interfaces

Science.gov (United States)

Carr, Elliot J.

2018-04-01

This paper presents a simple tool for characterizing the time scale for continuum diffusion processes through layered heterogeneous media. This mathematical problem is motivated by several practical applications such as heat transport in composite materials, flow in layered aquifers, and drug diffusion through the layers of the skin. In such processes, the physical properties of the medium vary across layers and internal boundary conditions apply at the interfaces between adjacent layers. To characterize the time scale, we use the concept of mean action time, which provides the mean time scale at each position in the medium by utilizing the fact that the transition of the transient solution of the underlying partial differential equation model, from initial state to steady state, can be represented as a cumulative distribution function of time. Using this concept, we define the characteristic time scale for a multilayer diffusion process as the maximum value of the mean action time across the layered medium. For given initial conditions and internal and external boundary conditions, this approach leads to simple algebraic expressions for characterizing the time scale that depend on the physical and geometrical properties of the medium, such as the diffusivities and lengths of the layers. Numerical examples demonstrate that these expressions provide useful insight into explaining how the parameters in the model affect the time it takes for a multilayer diffusion process to reach steady state.

Structural Characteristics and Physical Properties of Tectonically Deformed Coals

OpenAIRE

Yiwen Ju; Zhifeng Yan; Xiaoshi Li; Quanlin Hou; Wenjing Zhang; Lizhi Fang; Liye Yu; Mingming Wei

2012-01-01

Different mechanisms of deformation could make different influence on inner structure and physical properties of tectonically deformed coal (TDC) reservoirs. This paper discusses the relationship between macromolecular structure and physical properties of the Huaibei-Huainan coal mine areas in southern North China. The macromolecular structure and pore characteristics are systematically investigated by using techniques such as X-ray diffraction (XRD), high-resolution transmission electron mic...

Chemical and texture characteristics and sensory properties of “mozzarella” cheese from different feeding systems

Directory of Open Access Journals (Sweden)

R. Rubino

2010-02-01

Full Text Available The aim of this study was describing the chemical composition, the rheological characteristics and the sensory properties of “mozzarella” cheese produced with milk from buffalos fed with different diets. The study involved two farms and four feeding systems. In farm C, one group was mostly fed with Ryegrass Hay (RH and the other group with Ryegrass Silage (RS. In farm T, instead, one group was mostly fed with Corn Silage (CS and the other one with a Sorghum Silage (SS. In summer, three cheesemakings, for each farm and for each feeding system, were carried out at C.R.A. of Bella. In each farm, data were processed by the analysis of variance in order to compare the effects of two feeding systems. Some parameters of chemical and texture characteristics and sensory properties were influenced by the feeding system. Results were remarkable for the DOP products.

Development of melting and casting process for Nb-Al intermetallic compounds and mechanical properties

International Nuclear Information System (INIS)

Kamata, Kinya; Degawa, Toru; Nagashima, Yoshinori

1993-01-01

The shaping methods of Nb-Al intermetallic compounds, especially melting and casting, have considerably different characteristics as compared with those for other metals and alloys. The authors have investigated melting and casting processes for Nb-Al compounds to develop precision casting processes for these intermetallics. Fundamental properties of Nb-Al compound castings have been also investigated for high temperature structural use in this work. An advanced Induction Skull Melting (ISM) furnace has been developed and the advantages of ISM have been recognized as a result of this study. The mechanical properties, such as hardness and compression strength, are dependent upon the Al content in Nb-Al binary compounds

Macro-architectured cellular materials: Properties, characteristic modes, and prediction methods

Science.gov (United States)

Ma, Zheng-Dong

2017-12-01

Macro-architectured cellular (MAC) material is defined as a class of engineered materials having configurable cells of relatively large (i.e., visible) size that can be architecturally designed to achieve various desired material properties. Two types of novel MAC materials, negative Poisson's ratio material and biomimetic tendon reinforced material, were introduced in this study. To estimate the effective material properties for structural analyses and to optimally design such materials, a set of suitable homogenization methods was developed that provided an effective means for the multiscale modeling of MAC materials. First, a strain-based homogenization method was developed using an approach that separated the strain field into a homogenized strain field and a strain variation field in the local cellular domain superposed on the homogenized strain field. The principle of virtual displacements for the relationship between the strain variation field and the homogenized strain field was then used to condense the strain variation field onto the homogenized strain field. The new method was then extended to a stress-based homogenization process based on the principle of virtual forces and further applied to address the discrete systems represented by the beam or frame structures of the aforementioned MAC materials. The characteristic modes and the stress recovery process used to predict the stress distribution inside the cellular domain and thus determine the material strengths and failures at the local level are also discussed.

Investigation of thermo-optical characteristics of the interaction processes of laser radiation with silver nanoparticles

International Nuclear Information System (INIS)

Pustovalov, V K; Astafyeva, L G

2013-01-01

Metallic nanoparticles have been actively investigated in recent years by different optical and laser methods with the purpose of their applications in optoelectronics and photonics, chemistry, laser nanobiomedicine, optical diagnostics, and other fields. A major role among metallic nanoparticles is played by nanoparticles from the noble metals (silver, gold, etc). These particles have unique plasmonic properties (resonances in the range of wavelength 400–540 nm), which can be used for the absorption, scattering and transformation of laser energy. Analysis of the thermo-optical characteristics of the interaction processes of laser radiation with silver nanoparticles is carried out, taking into account absorption, scattering and extinction of laser radiation by nanoparticles, as well as the thermo-optical and other properties of nanoparticles. Estimations are made of the influence of these nanoparticle properties on the possible results of laser radiation interaction with silver nanoparticles, including heating, heat exchange, possible melting and evaporation, and processes in the ambient media. These results can be used in laser processing of silver nanoparticles and their applications in laser nanomedicine. (paper)

Uranium processing and properties

CERN Document Server

2013-01-01

Covers a broad spectrum of topics and applications that deal with uranium processing and the properties of uranium Offers extensive coverage of both new and established practices for dealing with uranium supplies in nuclear engineering Promotes the documentation of the state-of-the-art processing techniques utilized for uranium and other specialty metals

Drying characteristics and engineering properties of fermented ...

African Journals Online (AJOL)

The effect of variety on the drying and engineering properties of fermented ground cassava was studied in order to generate data for design and optimum performance of various dryers used in cassava processing. This research attempts to provide data on the engineering properties such as moisture content, specific heat ...

Characteristics and Properties of a Simple Linear Regression Model

Directory of Open Access Journals (Sweden)

Kowal Robert

2016-12-01

Full Text Available A simple linear regression model is one of the pillars of classic econometrics. Despite the passage of time, it continues to raise interest both from the theoretical side as well as from the application side. One of the many fundamental questions in the model concerns determining derivative characteristics and studying the properties existing in their scope, referring to the first of these aspects. The literature of the subject provides several classic solutions in that regard. In the paper, a completely new design is proposed, based on the direct application of variance and its properties, resulting from the non-correlation of certain estimators with the mean, within the scope of which some fundamental dependencies of the model characteristics are obtained in a much more compact manner. The apparatus allows for a simple and uniform demonstration of multiple dependencies and fundamental properties in the model, and it does it in an intuitive manner. The results were obtained in a classic, traditional area, where everything, as it might seem, has already been thoroughly studied and discovered.

Jarosite added concrete along with fly ash: Properties and characteristics in fresh state

Directory of Open Access Journals (Sweden)

Priyansha Mehra

2016-09-01

Full Text Available This paper presents the results of different properties and characteristics of jarosite added concrete along with fly ash during its fresh state. Jarosite is an industrial by product from zinc manufacturing industry obtained through hydrometallurgical process from its sulphide ore. It has been tried to incorporate jarosite in concrete as sand replacement. Different concrete mixtures have been prepared for three water–cement ratios (0.40, 0.45 and 0.50 and 5 jarosite replacement levels (0, 5, 10, 15, 20 and 25%. Cement has been partially replaced (25% by fly ash in all the concrete mixtures. Density, workability and setting & hardening of fresh concrete has been evaluated and analyzed. Keeping the environmental suitability of concrete in mind, toxicity leaching characteristic potential test has been performed on raw jarosite and concrete samples.

Girdler-sulfide process physical properties

International Nuclear Information System (INIS)

Neuburg, H.J.; Atherley, J.F.; Walker, L.G.

1977-05-01

Physical properties of pure hydrogen sulfide and of gaseous and liquid solutions of the H 2 S-H 2 O system have been formulated. Tables for forty-nine different properties in the pressure and temperature range of interest to the Girdler-Sulfide (GS) process for heavy water production are given. All properties are presented in SI units. A computer program capable of calculating properties of the pure components as well as gaseous mixtures and liquid solutions at saturated and non-saturated conditions is included. (author)

Quantifying the Interactions Between Soil Thermal Characteristics, Soil Physical Properties, Hydro-geomorphological Conditions and Vegetation Distribution in an Arctic Watershed

Science.gov (United States)

Dafflon, B.; Leger, E.; Robert, Y.; Ulrich, C.; Peterson, J. E.; Soom, F.; Biraud, S.; Tran, A. P.; Hubbard, S. S.

2017-12-01

Improving understanding of Arctic ecosystem functioning and parameterization of process-rich hydro-biogeochemical models require advances in quantifying ecosystem properties, from the bedrock to the top of the canopy. In Arctic regions having significant subsurface heterogeneity, understanding the link between soil physical properties (incl. fraction of soil constituents, bedrock depth, permafrost characteristics), thermal behavior, hydrological conditions and landscape properties is particularly challenging yet is critical for predicting the storage and flux of carbon in a changing climate. This study takes place in Seward Peninsula Watersheds near Nome AK and Council AK, which are characterized by an elevation gradient, shallow bedrock, and discontinuous permafrost. To characterize permafrost distribution where the top of permafrost cannot be easily identified with a tile probe (due to rocky soil and/or large thaw layer thickness), we developed a novel technique using vertically resolved thermistor probes to directly sense the temperature regime at multiple depths and locations. These measurements complement electrical imaging, seismic refraction and point-scale data for identification of the various thermal behavior and soil characteristics. Also, we evaluate linkages between the soil physical-thermal properties and the surface properties (hydrological conditions, geomorphic characteristics and vegetation distribution) using UAV-based aerial imaging. Data integration and analysis is supported by numerical approaches that simulate hydrological and thermal processes. Overall, this study enables the identification of watershed structure and the links between various subsurface and landscape properties in representative Arctic watersheds. Results show very distinct trends in vertically resolved soil temperature profiles and strong lateral variations over tens of meters that are linked to zones with various hydrological conditions, soil properties and vegetation

Manufacturing process and electrode properties of palladium-electroded ionic polymer–metal composite

International Nuclear Information System (INIS)

Chang, Longfei; Chen, Hualing; Zhu, Zicai; Li, Bo

2012-01-01

This paper primarily focuses on the manufacturing process of palladium-electroded ionic polymer–metal composite (IPMC). First, according to the special properties of Pd, many experiments were done to determine several specific procedures, including the addition of a reducing agent and the time consumed. Subsequently, the effects of the core manufacturing steps on the electrode morphology were revealed by scanning electron microscopy studies of 22 IPMC samples treated with different combinations of manufacturing steps. Finally, the effects of electrode characteristics on the electromechanical properties, including the sheet resistivity, the elastic modulus and the electro-active performance, of IPMCs were evaluated experimentally and analyzed according to the electrode morphology. (paper)

Influence of the surface layer characteristics on the regularities of the cutting process

Directory of Open Access Journals (Sweden)

Krainev Dmitriy V.

2017-01-01

Full Text Available The article considers the influence of the surface layer characteristics on the regularities of the cutting process and the formation of the quality of the surface machined. This effect has been confirmed by the study results of the combined cutting method with advanced plastic deformation (APD. The work estimates the impact of the change in the surface layer properties on the forces and temperature of cutting, stability of the chip formation and quality parameters of the surface machined.

Molecular dynamics study of dynamic and structural properties of supercooled liquid and glassy iron in the rapid-cooling processes

Energy Technology Data Exchange (ETDEWEB)

Cao, Qi-Long; Huang, Duo-Hui; Yang, Jun-Sheng; Wan, Min-Jie; Wang, Fan-Hou, E-mail: eatonch@gmail.com

2014-10-01

Molecular dynamics simulations were applied to study the dynamic and structural properties of supercooled liquid and glassy iron in the rapid-cooling processes. The mean-square displacement and the non-Gaussian parameter were used to describe the dynamic properties. The evolution of structural properties was investigated using the pair distribution functions and bond-angle distribution functions. Results for dynamic and structural relaxations indicate that the dynamic features are consistently correlated with the structure evolution, and there are three temperature regions as the temperature decreases: (1) at higher temperatures (1500 K, 1300 K, and 1100 K), the system remains in the liquid characteristics during the overall relaxation process. (2) At medial temperatures (1050 K, 900 K, and 700 K), a fast β-relaxation is followed by a much slower α-relaxation. There is a little change in the structural properties in the β-relaxation region, while major configuration rearrangements occurred in the α-relaxation range and the crystallization process was completed at the end of α-relaxation region. (3) At lower temperature (500 K), the system shows glassy characteristics during the overall relaxation process. In addition, the melting temperature, glass transition temperature and diffusion coefficients of supercooled liquid iron are also computed.

Nitinol laser cutting: microstructure and functional properties of femtosecond and continuous wave laser processing

Science.gov (United States)

Biffi, C. A.; Tuissi, A.

2017-03-01

Thermal processing can affect the properties of smart materials, and the correct selection of the best manufacturing technology is fundamental for producing high tech smart devices, containing embedded functional properties. In this work cutting of thin superelastic Nitinol plates using a femtosecond (fs) and continuous wave (CW) laser was studied. Diamond shaped elements were cut to characterize the kerf qualitative features; microstructural analysis of the cross sections allowed identification of thermal damage characteristics introduced into the material during the laser processes. A thermally undamaged microstructure was observed for fs laser cutting, while CW was seen to be characterized by a large heat-affected zone. Functional properties were investigated by differential scanning calorimetry and tensile testing of laser cut microelements and of the reference material. It was seen that the martensitic transformation behavior of Nitinol is not affected by fs regime, while cw cutting provokes an effect equivalent to a high temperature thermal treatment in the material surrounding the cutting kerf, degradating the material properties. Finally, tensile testing indicated that superelastic performances were guaranteed by fs regime, while strong reduction of the recoverable strain was detected in the CW processed sample.

The physical properties and compaction characteristics of swelling soils

International Nuclear Information System (INIS)

Komine, Hideo; Ogata, Nobuhide

1990-01-01

Expansive soils have recently attracted increasing attention as the back filling material for the repositories of high level nuclear wastes or as the material for improving extremely soft grounds. However, since very little has been known concerning the physical and mechanical properties of such materials, it is necessary to clarify the swelling, compaction and thermal characteristics of expansive soils. For this purpose, various kinds of index tests and a series of static compaction tests were performed using several kinds of swelling soils in order to investigate the relationship between the fundamental physical properties and the compaction characteristics. Since the ordinary testing method stipulated in JIS is difficult to perform for such expansive soils, the new method was proposed to obtained the reliable values of specific gravity, grain size distribution and liquid/plastic limits. By this method, some representative values were presented for various kinds of clay including bentonite. As the results of static compaction tests, the compaction characteristics of clay were strongly dependent on the plastic limit of clay. The maximum dry density and optimum water content were strongly dependent on both plastic limit and compaction pressure. (K.I.)

Properties of spatial Cox process models

DEFF Research Database (Denmark)

Møller, Jesper

2005-01-01

Particularly, we study the most important classes of Cox processes, including log Gaussian Cox processes, shot noise Cox processes, and permanent Cox processes. We consider moment properties and point process operations such as thinning, displacements, and super positioning. We also discuss how...... to simulate specific Cox processes....

Structure, processing, and properties of potatoes

Science.gov (United States)

Lloyd, Isabel K.; Kolos, Kimberly R.; Menegaux, Edmond C.; Luo, Huy; McCuen, Richard H.; Regan, Thomas M.

1992-06-01

The objective of this experiment and lesson intended for high school students in an engineering or materials science course or college freshmen is to demonstrate the relation between processing, structure, and thermodynamic and physical properties. The specific objectives are to show the effect of structure and structural changes on thermodynamic properties (specific heat) and physical properties (compressive strength); to illustrate the first law of thermodynamics; to compare boiling a potato in water with cooking it in a microwave in terms of the rate of structural change and the energy consumed to 'process' the potato; and to demonstrate compression testing.

Structure, processing, and properties of potatoes

Science.gov (United States)

Lloyd, Isabel K.; Kolos, Kimberly R.; Menegaux, Edmond C.; Luo, Huy; Mccuen, Richard H.; Regan, Thomas M.

1992-01-01

The objective of this experiment and lesson intended for high school students in an engineering or materials science course or college freshmen is to demonstrate the relation between processing, structure, and thermodynamic and physical properties. The specific objectives are to show the effect of structure and structural changes on thermodynamic properties (specific heat) and physical properties (compressive strength); to illustrate the first law of thermodynamics; to compare boiling a potato in water with cooking it in a microwave in terms of the rate of structural change and the energy consumed to 'process' the potato; and to demonstrate compression testing.

Determination of drying characteristics and quality properties of eggplant in different drying conditions

Directory of Open Access Journals (Sweden)

Gözde Bayraktaroglu Urun

2015-12-01

Full Text Available Drying is the most traditional process used for preserving eggplant a long time. The aim of this study was to determining drying characteristics and quality properties of eggplant dried by sun drying, hot air convective drying and infrared assisted convective drying. Convective drying and infrared assisted convective were carried out in a convective dryer at three different temperatures(40°, 50°, 60°C and air velocity at 5 m/s.The increasing of temperatures during the drying of eggplant led to a significant reduction of the drying time. However loss of nutrition was observed in eggplant samples dried at higher temperature.The biggest change in colour parameters was observed in samples dried with sun drying.So it was thought that sun drying had a negative effect on quality properties of eggplant samples.

Corrosion and Creep Characteristics of the HANA-4 Alloy with the various Manufacturing Processes

International Nuclear Information System (INIS)

Kim, Hyun-Gil; Choi, Byung-Kwan; Park, Jeong-Yong; Jeong, Yong-Hwan

2008-01-01

Zirconium alloys have been used as a fuel cladding material for several decades, since these alloys have revealed a good corrosion resistance and mechanical properties in reactor operating conditions. The development of an advanced Zr-based alloy with an improved corrosion and creep resistance is necessary for the high burn-up operating conditions in PWRs. The alloying element effects of the Nb, Sn, Fe, Cr, Cu etc as well as an optimization of the manufacturing processes such as the reduction ratio and annealing temperatures have been studied to improve the corrosion and creep properties. A high Nb-containing Zr-based alloy named HANA-4 was designed at KAERI and its nominal composition is Zr-1.5Nb-0.4Sn-0.2Fe-0.1Cr in wt.%. For high Nb-containing Zr alloys, their corrosion resistance is very sensitive to their microstructural characteristics which are determined by a manufacturing process. In order to obtain the best manufacturing process for the HANA-4 alloy, various evaluations such as corrosion and creep tests, a microstructural analysis, and a texture analysis were performed on the HANA-4 alloy with various manufacturing processes

Path and semimartingale properties of chaos processes

DEFF Research Database (Denmark)

Basse-O'Connor, Andreas; Graversen, Svend-Erik

2010-01-01

The present paper characterizes various properties of chaos processes which in particular include processes where all time variables admit a Wiener chaos expansion of a fixed finite order. The main focus is on the semimartingale property, p-variation and continuity. The general results obtained...

Effects of instant controlled pressure drop process on physical and sensory properties of puffed wheat snack.

Science.gov (United States)

Yağcı, Sibel

2017-04-01

In this study, research on the development of a puffed wheat snack using the instant controlled pressure drop (DIC) process was carried out. Snack products were produced by expanding moistened wheat under various DIC processing conditions in order to obtain adequate puffing, followed by drying in a hot air dryer. The effects of operational variables such as wheat initial moisture content (11-23% w/w, wet basis), processing pressure (3-5 × 10 2 kPa) and processing time (3-11 min) on the physical (density, color and textural characteristics) and sensory properties of the product were investigated. The physical properties of the wheat snack were most affected by changes in processing pressure, followed by processing time and wheat moisture content. Increasing processing pressure and time often improved expansion and textural properties but led to darkening of the raw wheat color. The most acceptable snack in terms of physical properties was obtained at the lowest wheat moisture content. Sensory analysis suggested that consumer acceptability was optimal for wheat snacks produced at higher processing pressure, medium processing time and lower moisture content. The most desirable conditions for puffed wheat snack production using the DIC process were determined as 11% (w/w) of wheat moisture content, 5 × 10 2 kPa of processing pressure and 7 min of processing time. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Process industry properties in nuclear industry

International Nuclear Information System (INIS)

Zheng Hualing

2005-01-01

In this article the writer has described the definition of process industry, expounded the fact classifying nuclear industry as process industry, compared the differences between process industry and discrete industry, analysed process industry properties in nuclear industry and their important impact, and proposed enhancing research work on regularity of process industry in nuclear industry. (authors)

Characteristic properties of crystals. Their demonstration; Proprietes caracteristiques des cristaux. Mise en evidence

Energy Technology Data Exchange (ETDEWEB)

Lesueur, C

1951-03-01

The characteristic properties of scintillation crystals discussed are the photon spectrum emitted by passage of a particle, number of these photons, transparence of the crystal to its own fluorescence radiation, and decay period of the fluorescence. The experimental apparatus, consisting of photomultiplier tube, preamplifier, amplifier, discriminator, and scaler, is described, and the experimental evaluation of the characteristic properties is discussed. Results of tests on various crystals with {alpha} and {beta} radiations are reported graphically.

Thermoset-cellulose nanocomposites: Flammability characteristics

CSIR Research Space (South Africa)

Mngomezulu, Mfiso E

2017-04-01

Full Text Available . They have remarkable combination of properties including light weight, high mechanical, thermal and thermo-mechanical characteristics, excellent dielectric properties, dimensional stability and are easy to process. Furthermore, these composite materials show...

Processes of hydration aging of superconducting ceramics and problem of regeneration of properties

International Nuclear Information System (INIS)

Komarov, A.V.; Popov, V.P.; Tikhonov, P.A.

1989-01-01

The process of hydration aging (distilled water, saturated water vapors) of YBa 2 Cu 3 O 6.5+x specimens with T s of about 95 K was studied at 55 deg C and water vapors pressure of 119 mmHg. It is established that depending on exposure time and saturated vapors pressure, water affects electric properties of yttrium-barium ceramics with different degree of the effect reversibility. Valuable regeneration of the characteristics can occur only when the hydration process has not led to changes in the phase composition of the material. The mechanism of interaction between cermaics and water is given

The impact of the manufacturing process on the hardness and sensory properties of milk chocolate

Directory of Open Access Journals (Sweden)

Zarić Danica B.

2012-01-01

Full Text Available The aim of this paper was to examine the impact of the manufacturing process on the textural characteristics and sensory properties of milk chocolate. The research was conducted on the samples of chocolate produced in a ball mill during 30, 60 and 90 minutes of refining, each of them being pre-crystallized at 26, 28 and 30°C. A chocolate mass of identical ingredient composition was also produced using a standard manufacturing process at the same pre-crystallization temperatures. Chocolate hardness was examined using a piece of equipment called Texture Analyser, measuring the stress intensity which leads to chocolate crushing. Sensory analysis was performed using the point scoring method. The new manufacturing process, i.e. the manufacturing of chocolate in a ball mill improves sensory properties and hardness of milk chocolate. [Projekat Ministarstva nauke Republike Srbije, br. TR 31014

Aging characteristic and mechanical properties of TiC/2618 composite

Institute of Scientific and Technical Information of China (English)

龙春光; 张厚安; 庞佑霞; 刘厚才

2001-01-01

TiC/2618 composite was prepared by XD method . The constituent and microstructure of the composite have been investigated by X-ray diffraction and TEM technique. The aging characteristics and mechanical properties at high and room temperatures were studied. The results show that: 1 ) it is possible to prepare multiple alloy matrix TiC/2618composite by XD method; 2) the TiC particles in TiC/2618 composite have the characteristics of fine size, clean appearance and a good bond with the matrix; 3) the aging law of the TiC/2618 composite has been changed by the addition of TiC particles. Two-peak value phenomenon has been observed when it was aged at 190 ℃; 4) TiC/2618 composite has better mechanical properties than those of the matrix both at room and high temperatures.

Correlation analysis of protein quality characteristics with gluten-free bread properties.

Science.gov (United States)

Horstmann, S W; Foschia, M; Arendt, E K

2017-07-19

The interest in gluten-free cereal products has increased significantly over the last number of years and there is still a high demand for high quality products. This study aims to establish possible connections between protein properties and dough and bread quality which could advance the knowledge for gluten-free product development. The objective of the present study was to correlate protein properties with bread characteristics. Therefore, a wide range of tests (solubility, emulsifying, foaming, water hydration properties) was performed to characterize a range of food proteins (potato, pea, carob, lupin and soy). Furthermore, the performance of these proteins in a dough matrix (pasting, rheology) and bread formulation (volume, structure, and texture) was analysed. Statistical analysis showed significant (p bread characteristics. The addition of the proteins to the gluten-free bread formulation affected pasting rheological and bread characteristics such as crumb density, crumb hardness and specific volume. The addition of potato and soy protein resulted in the lowest volume with a dense crumb structure and a low consumer acceptance score. However, lupin, pea and carob containing gluten-free breads had a higher specific volume and softer and less dense crumb structure. The protein solubility (r, 0.89; p bread quality.

Soil properties and processes

NARCIS (Netherlands)

Hartemink, A.E.; McBratney, A.B.; White, R.E.

2009-01-01

This four-volume set, edited by leading experts in soil science, brings together in one collection a series of papers that have been fundamental to the development of soil science as a defined discipline. Tis volume 2 on Soil Properties and Processes covers: - Soil physics - Soil (bio)chemistry -

Dynamic characteristics of heterogeneous media in vibrational and wave processes

International Nuclear Information System (INIS)

Fedotovskij, V.S.; Sinyavskij, V.F.; Terenik, L.V.; Spirov, V.S.; Kokorev, B.V.

1986-01-01

The complex mechanic systems involving a great quantity of the same type elements, in particular, the rod systems flowed around by the one- or two-phase flow are considered as the two- or three-phase heterogeneous media with certain effective properties. Some recommendations for calculating effective properties and determining those on a base of the dynamic characteristics of various heterogeneous systems are given. (author)

Influence of monomer on structure, processing and application characteristics of UV curable urethane acrylate composite coatings

International Nuclear Information System (INIS)

Grigale-Sorocina, Z; Kalnins, M; Gross, K A

2016-01-01

Increased interest in the esthetical natural nail coatings have encouraged more in-depth studies particularly of UV curable coatings: their formation, processing, structure, characteristics and removing. Typical requirement for nail coatings is good adhesion, but preferably for the short time of functioning (usual 2-4 weeks). This study investigated the impact of four different monomers (tertiobutyl cyclohexyl acrylate (TBCHA), ethylene glycol dimethacrylate (EGDMA), tetrahydrofurfuryl acrylate (THFA), hydroxypropyl methacrylate (HPMA)) to viscosity of uncured mixture and degree of conversion, mechanical properties, surface gloss, micro hardness and adhesion loss for cured films. Specific coating application requires comparatively high coating flexibility and stability of deformation characteristics. This can be achieved with composition containing 30% of monomer TBCHA, what shows ultimate elongation ε B = 0,23 - 0,24, modulus of elasticity E = 670-710 MPa and comparatively constant properties in 72 hours (ΔE = 1.3%, Δε B =6.0%). A composition with 40% of TBCHA shows the fastest coating destruction achieving adhesion loss within 3 min. (paper)

Moisture sorption–desorption characteristics and the corresponding thermodynamic properties of carvedilol phosphate

Directory of Open Access Journals (Sweden)

Ravikiran Allada

2017-01-01

Full Text Available Aims: Carvedilol phosphate (CDP is a nonselective beta-blocker used for the treatment of heart failures and hypertension. In this work, moisture sorption–desorption characteristics and thermodynamic properties of CDP have been investigated. Materials and Methods: The isotherms were determined using dynamic vapor sorption analyzer at different humidity conditions (0%–90% relative humidity and three pharmaceutically relevant temperatures (20°C, 30°C, and 40°C. The experimental sorption data determined were fitted to various models, namely, Brunauer–Emmett–Teller; Guggenheim-Anderson-De Boer (GAB; Peleg; and modified GAB. Isosteric heats of sorption were evaluated through the direct use of sorption isotherms by means of the Clausius-Clapeyron equation. Statistical Analysis Used: The sorption model parameters were determined from the experimental sorption data using nonlinear regression analysis, and mean relative percentage deviation (P, correlation (Correl, root mean square error, and model efficiency were considered as the criteria to select the best fit model. Results: The sorption–desorption isotherms have sigmoidal shape – confirming to Type II isotherms. Based on the statistical data analysis, modified GAB model was found to be more adequate to explain sorption characteristics of CDP. It is noted that the rate of adsorption and desorption is specific to the temperature at which it was being studied. It is observed that isosteric heat of sorption decreased with increasing equilibrium moisture content. Conclusions: The calculation of the thermodynamic properties was further used to draw an understanding of the properties of water and energy requirements associated with the sorption behavior. The sorption–desorption data and the set of equations are useful in the simulation of processing, handling, and storage of CDP and further behavior during manufacture and storage of CDP formulations.

Effect of packaging on physicochemical characteristics of irradiated pre-processed chicken

International Nuclear Information System (INIS)

Jiang Xiujie; Zhang Dongjie; Zhang Dequan; Li Shurong; Gao Meixu; Wang Zhidong

2011-01-01

To explore the effect of modified atmosphere packaging and antioxidants on the physicochemical characteristics of irradiated pre-processed chicken, the pre-processed chicken was added antioxidants first, and then packaged in common, vacuum and gas respectively, and finally irradiated at 5 kGy dosage. All samples was stored at 4 ℃. The pH, TBA, TVB-N and color deviation were evaluated after 0, 3, 7, 10, 14, 18 and 21 d of storage. The results showed that pH value of pre-processed chicken with antioxidants and vacuum packaged increased with the storage time but not significantly among different treatments. The TBA value was also increased but not significantly (P > 0.05), which indicated that vacuum package inhibited the lipid oxidation. TVB-N value increased with storage time, TVB-N value of vacuum package samples reached 14.29 mg/100 g at 21 d storage, which did not exceeded the reference indexes of fresh meat. a * value of the pre-processed chicken of vacuum package and non-oxygen package samples increased significantly during storage (P > 0.05), and chicken color kept bright red after 21 d storage with vacuum package It is concluded that vacuum packaging of irradiated pre-processed chicken is effective on ensuring its physical and chemical properties during storage. (authors)

Investigation of radiation keeping property of barite coated cloth via image processing method

Science.gov (United States)

Kilinçarslan, Ş.; Akkurt, İ.; Molla, T.; Akarslan, F.

2012-09-01

Preservative clothes which are able to absorb radiation beam are needed not only for saving people working at radioactive environment but also for saving others from natural and man-made radiation sources we are exposed in daily life. Barite is a mineral which can be used for armour plating because of high atomic numbered element barium constituent of barite. In this study, armour plating property of barite was applied to fabrics. Barite coated fabric having characteristic of keeping radiation was obtained by penetrating barite on cloth via coating method. Radiation keeping property of fabrics obtained was determined via image processing. The results of experiments showed that barite coated fabrics have blocked radiation more than normal fabrics have done.

Investigation of radiation keeping property of barite coated cloth via image processing method

Energy Technology Data Exchange (ETDEWEB)

Kilincarslan, S.; Akkurt, I.; Molla, T.; Akarslan, F. [Department of Construction Education, Suleyman Demirel University, Isparta (Turkey); Department of Physics, Science Faculty, Suleyman Demirel University, Isparta (Turkey); Department of Construction Education, Suleyman Demirel University, Isparta (Turkey); Textil Engineering, Engineering Faculty, Suleyman Demirel University, Isparta (Turkey)

2012-09-06

Preservative clothes which are able to absorb radiation beam are needed not only for saving people working at radioactive environment but also for saving others from natural and man-made radiation sources we are exposed in daily life. Barite is a mineral which can be used for armour plating because of high atomic numbered element barium constituent of barite. In this study, armour plating property of barite was applied to fabrics. Barite coated fabric having characteristic of keeping radiation was obtained by penetrating barite on cloth via coating method. Radiation keeping property of fabrics obtained was determined via image processing. The results of experiments showed that barite coated fabrics have blocked radiation more than normal fabrics have done.

Investigation of radiation keeping property of barite coated cloth via image processing method

International Nuclear Information System (INIS)

Kilinçarslan, Ş.; Akkurt, İ.; Molla, T.; Akarslan, F.

2012-01-01

Preservative clothes which are able to absorb radiation beam are needed not only for saving people working at radioactive environment but also for saving others from natural and man-made radiation sources we are exposed in daily life. Barite is a mineral which can be used for armour plating because of high atomic numbered element barium constituent of barite. In this study, armour plating property of barite was applied to fabrics. Barite coated fabric having characteristic of keeping radiation was obtained by penetrating barite on cloth via coating method. Radiation keeping property of fabrics obtained was determined via image processing. The results of experiments showed that barite coated fabrics have blocked radiation more than normal fabrics have done.

Property impacts on Carbon Capture and Storage (CCS) processes: A review

International Nuclear Information System (INIS)

Tan, Yuting; Nookuea, Worrada; Li, Hailong; Thorin, Eva; Yan, Jinyue

2016-01-01

Highlights: • Property impacts on CCS processes have been reviewed. • Properties were ranked and priority of properties in model development was analyzed. • Relevant properties in the design and operation of CCS processes have been identified. • The studied CCS processes include CO_2 capture, conditioning, transport and storage. - Abstract: The knowledge of thermodynamic and transport properties of CO_2-mixtures is important for designing and operating different processes in carbon capture and storage systems. A literature survey was conducted to review the impact of uncertainty in thermos-physical properties on the design and operation of components and processes involved in CO_2 capture, conditioning, transport and storage. According to the existing studies on property impacts, liquid phase viscosity and diffusivity as well as gas phase diffusivity significantly impact the process simulation and absorber design for chemical absorption. Moreover, the phase equilibrium is important for regenerating energy estimation. For CO_2 compression and pumping processes, thermos-physical properties have more obvious impacts on pumps than on compressors. Heat capacity, density, enthalpy and entropy are the most important properties in the pumping process, whereas the compression process is more sensitive to heat capacity and compressibility. In the condensation and liquefaction process, the impacts of density, enthalpy and entropy are low on heat exchangers. For the transport process, existing studies mainly focused on property impacts on the performance of pipeline steady flow processes. Among the properties, density and heat capacity are most important. In the storage process, density and viscosity have received the most attention in property impact studies and were regarded as the most important properties in terms of storage capacity and enhanced oil recovery rate. However, for physical absorption, physical adsorption and membrane separation, there has been a

Phases of fracture process zone and tension softening properties of concrete

International Nuclear Information System (INIS)

Mihashi, H.; Nomura, N.

1991-01-01

The safety and serviceability of concrete structures are influenced very much by the cracking behavior of concrete. Since comprehensive numerical analysis techniques have been extensively developed to predict the mechanical behavior of concrete structures in the limit state, it is essential to study the constitutive laws to describe the cracking behavior of concrete in detail. The tension softening behavior of concrete is highly dominated by the existence of a fracture process zone (FPZ) ahead of a crack tip. Since the direct observation of the FPZ of concrete is hardly possible, the indirect techniques are applied, but it is still ambiguous what happens in the FPZ and how it affects the tension softening property. The purpose of this study is to present the property of the FPZ focusing on the influence of material structures by means of three-dimensional acoustic emission. These results are correlated to tension softening behavior evaluated by a numerical analysis to discuss how the tension softening property is related to the characteristics of the FPZ. The test procedure and the results are reported. (K.I.)

Investigation and development of a non-destructive system to evaluate critical properties of asphalt pavements during the compaction process.

Science.gov (United States)

2013-10-01

The purpose of this report is to present findings from a two-stage investigation to develop a non-destructive system to : evaluate critical properties and characteristics of asphalt pavements during the compaction process. The first stage aligned : c...

Property Modelling and Databases in Product-Process Design

DEFF Research Database (Denmark)

Gani, Rafiqul; Sansonetti, Sascha

of the PC-SAFT is used. The developed database and property prediction models have been combined into a properties-software that allows different product-process design related applications. The presentation will also briefly highlight applications of the software for virtual product-process design...

Surface properties and field emission characteristics of chemical vapor deposition diamond grown on Fe/Si substrates

International Nuclear Information System (INIS)

Hirakuri, Kenji; Yokoyama, Takahiro; Enomoto, Hirofumi; Mutsukura, Nobuki; Friedbacher, Gernot

2001-01-01

Electron field emission characteristics of diamond grains fabricated on iron dot-patterned silicon (Fe/Si) substrates at different methane concentrations have been investigated. The characteristics of the samples could be improved by control of the methane concentration during diamond fabrication. Etching treatment of the as-grown diamond has enhanced the emission properties both with respect to current and threshold voltage. In order to study the influence of etching effects on the field emission characteristics, the respective surfaces were studied by Raman spectroscopy, Auger electron spectroscopy, and electron spectroscopy for chemical analysis (ESCA). ESCA revealed intensive graphite and FeO x peaks on the sample surface grown at high methane concentration. For the etched samples, the peaks of diamond and silicon carbide were observed, and the peaks of nondiamond carbon disappeared. The experimental results show that the etching process removes graphitic and nondiamond carbon components. [copyright] 2001 American Institute of Physics

Effect of heat treatment on the characteristics of tool steel deposited by the directed energy deposition process

Science.gov (United States)

Park, Jun Seok; Lee, Min-Gyu; Cho, Yong-Jae; Sung, Ji Hyun; Jeong, Myeong-Sik; Lee, Sang-Kon; Choi, Yong-Jin; Kim, Da Hye

2016-01-01

The directed energy deposition process has been mainly applied to re-work and the restoration of damaged steel. Differences in material properties between the base and the newly deposited materials are unavoidable, which may affect the mechanical properties and durability of the part. We investigated the effect of heat treatment on the characteristics of tool steel deposited by the DED process. We prepared general tool steel materials of H13 and D2 that were deposited onto heat-treated substrates of H13 and D2, respectively, using a direct metal tooling process. The hardness and microstructure of the deposited steel before and after heat treatment were investigated. The hardness of the deposited H13 steel was higher than that of wrought H13 steel substrate, while that of the deposited D2 was lower than that of wrought D2. The evolution of the microstructures by deposition and heat treatment varied depending on the materials. In particular, the microstructure of the deposited D2 steel after heat treatment consisted of fine carbides in tempered martensite and it is expected that the deposited D2 steel will have isotropic properties and high hardness after heat treatment.

Electromagnetic absorbing property of the flaky carbonyl iron particles by chemical corrosion process

Energy Technology Data Exchange (ETDEWEB)

Zheng, Dianliang, E-mail: 272895980@qq.com [College of Aeronautical Engineering, Jilin Institute of Chemical Technology, Jilin 132022 (China); Liu, Ting; Zhou, Li [College of Aeronautical Engineering, Jilin Institute of Chemical Technology, Jilin 132022 (China); Xu, Yonggang [Science and Technology on Electromagnetic Scattering Laboratory, Shanghai 200438 (China)

2016-12-01

The flaky carbonyl iron particles (CIPs) were prepared using a milling process at the first step, then the chemical corrosion process was done to optimize the particle shape. The particle morphology was characterized by the scanning electron microscopy, the static magnetic property was evaluated on a vibrating sample magnetometer and X-ray diffraction (XRD) patterns were done to analyze the particle crystal grain structure. The complex permittivity and permeability were measured using a vector network analyzer in the frequency range of 2–18 GHz and the reflection loss (RL) was calculated. The results showed that the saturation magnetization value of the CIPs decreased as the CIPs was corroded to the small flakes in chemical corrosion process. The diffraction peaks of the single α-Fe existed in the XRD pattern of CIPs, and the characteristic peaks was more obvious and the intensity of the diffraction pattern was lower by corrosion. The permittivity and the permeability of the corroded milling CIPs was a little larger than the milling CIPs, it was due to the larger aspect ratio based on the fitting calculation process. At thickness 0.6 mm and 0.8 mm, the corroded milling CIPs composite had the better absorbing property than the other two samples. The frequency band (RL<−5 dB) could be widened to 8.96–18 GHz at 0.6 mm and 5.92–18 GHz at 0.8 mm, and RL less than −8 dB began to exist in 8.96–14.72 GHz at 0.8 mm. - Graphical abstract: The property of absorber using corrosion process could be enhanced. - Highlights: • The chemical corrosion process was done to optimize the particle shape. • The permittivity and permeability of corroded milling CIPs increased. • The aspect ratio of flaky CIPs increased in the corrosion process. • The corroded milling CIPs composite had the better absorbing property.

Comparison of Composites Properties Manufactured by Vacuum Process and Autoclave Process

Directory of Open Access Journals (Sweden)

MA Rufei

2017-01-01

Full Text Available Two kinds of prepregs ZT7G/LT-03A(unidirectional carbon fiber prepreg and ZT7G3198P/LT-03A(plain carbon fabric prepreg were used to manufacture three Bateches of composites by vacuum process and autoclave process respectively. The physical properties of the prepregs and mechanical properties of composite were tested. The performance, fiber volume content and porosity of composites manufactured by vacuum cure and autoclave process show that the physical property retention rates of vacuum cured composites are all over 75%, some even more than 100%. Interlaminar shear strength keeps the lowest retention rate and warp tensile strength keeps the highest retention in unidirectional carbon fiber composites. For fabric composite material, compression strength keeps the lowest and warp tensile strength keeps the highest retention. Vacuum cured composites perform lower fiber volume content and higher porosity, which are the main reasons of the lower performance.

Effect of extrusion processing on the microstructure, mechanical properties, biocorrosion properties and antibacterial properties of Ti-Cu sintered alloys

International Nuclear Information System (INIS)

Zhang, Erlin; Li, Shengyi; Ren, Jing; Zhang, Lan; Han, Yong

2016-01-01

Ti-Cu sintered alloys, Ti-Cu(S) alloy, have exhibited good anticorrosion resistance and strong antibacterial properties, but low ductility in previous study. In this paper, Ti-Cu(S) alloys were subjected to extrusion processing in order to improve the comprehensive property. The phase constitute, microstructure, mechanical property, biocorrosion property and antibacterial activity of the extruded alloys, Ti-Cu(E), were investigated in comparison with Ti-Cu(S) by X-ray diffraction (XRD), optical microscopy (OM), scanning electronic microscopy (SEM) with energy disperse spectroscopy (EDS), mechanical testing, electrochemical testing and plate-count method in order to reveal the effect of the extrusion process. XRD, OM and SEM results showed that the extrusion process did not change the phase constitute but refined the grain size and Ti 2 Cu particle significantly. Ti-Cu(E) alloys exhibited higher hardness and compressive yield strength than Ti-Cu(S) alloys due to the fine grain and Ti 2 Cu particles. With the consideration of the total compressive strain, it was suggested that the extrusion process could improve the ductility of Ti-Cu alloy(S) alloys. Electrochemical results have indicated that the extrusion process improved the corrosion resistance of Ti-Cu(S) alloys. Plate-count method displayed that both Ti-Cu(S) and Ti-Cu(E) exhibited strong antibacterial activity (> 99%) against S. aureus. All these results demonstrated that hot forming processing, such as the extrusion in this study, refined the microstructure and densified the alloy, in turn improved the ductility and strength as well as anticorrosion properties without reduction in antibacterial properties. - Highlights: • Hot extrusion refined the grain size and Ti 2 Cu phase significantly. • Hot extrusion increased the mechanical properties and the corrosion resistance. • The antibacterial properties was not affected by the hot process.

Fabrication process optimization for improved mechanical properties of Al 7075/SiCp metal matrix composites

Directory of Open Access Journals (Sweden)

Dipti Kanta Das

2016-04-01

Full Text Available Two sets of nine different silicon carbide particulate (SiCp reinforced Al 7075 Metal Matrix Composites (MMCs were fabricated using liquid metallurgy stir casting process. Mean particle size and weight percentage of the reinforcement were varied according to Taguchi L9 Design of Experiments (DOE. One set of the cast composites were then heat treated to T6 condition. Optical micrographs of the MMCs reveal consistent dispersion of reinforcements in the matrix phase. Mechanical properties were determined for both as-cast and heat treated MMCs for comparison of the experimental results. Linear regression models were developed for mechanical properties of the heat treated MMCs using list square method of regression analysis. The fabrication process parameters were then optimized using Taguchi based grey relational analysis for the multiple mechanical properties of the heat treated MMCs. The largest value of mean grey relational grade was obtained for the composite with mean particle size 6.18 µm and 25 weight % of reinforcement. The optimal combination of process parameters were then verified through confirmation experiments, which resulted 42% of improvement in the grey relational grade. Finally, the percentage of contribution of each process parameter on the multiple performance characteristics was calculated through Analysis of Variance (ANOVA.

Chemical transformations of characteristic hop secondary metabolites in relation to beer properties and the brewing process: a review.

Science.gov (United States)

Steenackers, Bart; De Cooman, Luc; De Vos, Dirk

2015-04-01

The annual production of hops (Humulus lupulus L.) exceeds 100,000 mt and is almost exclusively consumed by the brewing industry. The value of hops is attributed to their characteristic secondary metabolites; these metabolites are precursors which are transformed during the brewing process into important bittering, aromatising and preservative components with rather low efficiency. By selectively transforming these components off-line, both their utilisation efficiency and functionality can be significantly improved. Therefore, the chemical transformations of these secondary metabolites will be considered with special attention to recent advances in the field. The considered components are the hop alpha-acids, hop beta-acids and xanthohumol, which are components unique to hops, and alpha-humulene and beta-caryophyllene, sesquiterpenes which are highly characteristic of hops. Copyright © 2014 Elsevier Ltd. All rights reserved.

Viscoelastic characteristics and phytochemical properties of purple-rice drinks following ultrahigh pressure and pasteurization

Science.gov (United States)

Worametrachanon, Srivilai; Apichartsrangkoon, Arunee

2014-10-01

This study investigated how pressure (500, 600 MPa/20 min) altered the viscoelastic characteristics and phytochemical properties of germinated and non-germinated purple-rice drinks in comparison with pasteurization. Accordingly, color parameters, storage and loss moduli, anthocyanin content, γ-oryzanol, γ-aminobutyric acid (GABA), total phenolic compounds and 2,2-diphenyl-1-picrylthydrazyl (DPPH) capacity of the processed drinks were determined. The finding showed that germinated and pressurized rice drink had lower Browning Index than the non-germinated and pasteurized rice drink. The plots of storage and loss moduli for processed rice drinks indicated that time of pressurization had greater impact on gel structural modification than the level of pressure used. The phytochemicals, including total phenolics, and DPPH capacity in pressurized rice drinks retained higher quantity than those in pasteurized drink, despite less treatment effects on anthocyanin. On the contrary, both γ-oryzanol and GABA were found in high amounts in germinated rice drink with little variation among processing effects.

Characteristic Properties of Equivalent Structures in Compositional Models

Czech Academy of Sciences Publication Activity Database

Kratochvíl, Václav

2011-01-01

Roč. 52, č. 5 (2011), s. 599-612 ISSN 0888-613X R&D Projects: GA MŠk 1M0572; GA ČR GA201/09/1891; GA ČR GEICC/08/E010 Grant - others:GA MŠk(CZ) 2C06019 Institutional research plan: CEZ:AV0Z10750506 Keywords : Equivalence problem * Compositional model * Persegram * Characteristic properties Subject RIV: BA - General Mathematics Impact factor: 1.948, year: 2011 http://library.utia.cas.cz/separaty/2011/MTR/kratochvil-0359927. pdf

Reflection properties of road surfaces. Contribution to OECD Scientific Expert Group AC4 on Road Surface Characteristics.

NARCIS (Netherlands)

Schreuder, D.A.

1983-01-01

Photometric characteristics of road surfaces are dealt with. Representation of reflection properties in public lighting; quality criteria of road lighting installations; classification of road surfaces; the relation between reflection characteristics and other properties of road pavements in public

The Initial Regression Statistical Characteristics of Intervals Between Zeros of Random Processes

Directory of Open Access Journals (Sweden)

V. K. Hohlov

2014-01-01

Full Text Available The article substantiates the initial regression statistical characteristics of intervals between zeros of realizing random processes, studies their properties allowing the use these features in the autonomous information systems (AIS of near location (NL. Coefficients of the initial regression (CIR to minimize the residual sum of squares of multiple initial regression views are justified on the basis of vector representations associated with a random vector notion of analyzed signal parameters. It is shown that even with no covariance-based private CIR it is possible to predict one random variable through another with respect to the deterministic components. The paper studies dependences of CIR interval sizes between zeros of the narrowband stationary in wide-sense random process with its energy spectrum. Particular CIR for random processes with Gaussian and rectangular energy spectra are obtained. It is shown that the considered CIRs do not depend on the average frequency of spectra, are determined by the relative bandwidth of the energy spectra, and weakly depend on the type of spectrum. CIR properties enable its use as an informative parameter when implementing temporary regression methods of signal processing, invariant to the average rate and variance of the input implementations. We consider estimates of the average energy spectrum frequency of the random stationary process by calculating the length of the time interval corresponding to the specified number of intervals between zeros. It is shown that the relative variance in estimation of the average energy spectrum frequency of stationary random process with increasing relative bandwidth ceases to depend on the last process implementation in processing above ten intervals between zeros. The obtained results can be used in the AIS NL to solve the tasks of detection and signal recognition, when a decision is made in conditions of unknown mathematical expectations on a limited observation

Fixed-point Characterization of Compositionality Properties of Probabilistic Processes Combinators

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Daniel Gebler

2014-08-01

Full Text Available Bisimulation metric is a robust behavioural semantics for probabilistic processes. Given any SOS specification of probabilistic processes, we provide a method to compute for each operator of the language its respective metric compositionality property. The compositionality property of an operator is defined as its modulus of continuity which gives the relative increase of the distance between processes when they are combined by that operator. The compositionality property of an operator is computed by recursively counting how many times the combined processes are copied along their evolution. The compositionality properties allow to derive an upper bound on the distance between processes by purely inspecting the operators used to specify those processes.

A Study on the Kinetic Characteristics of Transmutation Process Reactor

Energy Technology Data Exchange (ETDEWEB)

Chung, Chang Hyun; You, Young Woo; Cho, Jae seon; Huh, Chang Wook; Kim, Doh Hyung [Seoul National University, Seoul (Korea, Republic of)

1997-07-01

The purpose of this study is to examine the transient heat transfer characteristics of liquid mental as the coolant used in accelerator-driven transmutation process reactor which is related the disposal of high-level radioactive nuclide. At current stage, the accelerator-driven transmutation process is investigated as the most appropriate method among many transmutation process methods. In this study, previous research works are investigated especially about the thermal hydraulics and kinetic behavior of coolant material including heat transfer of coolant in transmutation process reactor. A study on the heat transfer characteristics of liquid metal is performed based on the thermal hydraulic kinetic characteristics of liquid metal reactor which uses liquid metal coolant. Based on this study, the most appropriate material for the coolant of transmutation reactor will be recommended. 53 refs., 15 tabs., 33 figs. (author)

Simulation of the Press Hardening Process and Prediction of the Final Mechanical Material Properties

Science.gov (United States)

Hochholdinger, Bernd; Hora, Pavel; Grass, Hannes; Lipp, Arnulf

2011-08-01

Press hardening is a well-established production process in the automotive industry today. The actual trend of this process technology points towards the manufacturing of parts with tailored properties. Since the knowledge of the mechanical properties of a structural part after forming and quenching is essential for the evaluation of for example the crash performance, an accurate as possible virtual assessment of the production process is more than ever necessary. In order to achieve this, the definition of reliable input parameters and boundary conditions for the thermo-mechanically coupled simulation of the process steps is required. One of the most important input parameters, especially regarding the final properties of the quenched material, is the contact heat transfer coefficient (IHTC). The CHTC depends on the effective pressure or the gap distance between part and tool. The CHTC at different contact pressures and gap distances is determined through inverse parameter identification. Furthermore a simulation strategy for the subsequent steps of the press hardening process as well as adequate modeling approaches for part and tools are discussed. For the prediction of the yield curves of the material after press hardening a phenomenological model is presented. This model requires the knowledge of the microstructure within the part. By post processing the nodal temperature history with a CCT diagram the quantitative distribution of the phase fractions martensite, bainite, ferrite and pearlite after press hardening is determined. The model itself is based on a Hockett-Sherby approach with the Hockett-Sherby parameters being defined in function of the phase fractions and a characteristic cooling rate.

Impact of physical properties of mixture of diesel and biodiesel fuels on hydrodynamic characteristics of fuel injection system

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Filipović Ivan M.

2014-01-01

Full Text Available One of the alternative fuels, originating from renewable sources, is biodiesel fuel, which is introduced in diesel engines without major construction modifications on the engine. Biodiesel fuel, by its physical and chemical properties, is different from diesel fuel. Therefore, it is expected that by the application of a biodiesel fuel, the characteristic parameters of the injection system will change. These parameters have a direct impact on the process of fuel dispersion into the engine cylinder, and mixing with the air, which results in an impact on the quality of the combustion process. Method of preparation of the air-fuel mixture and the quality of the combustion process directly affect the efficiency of the engine and the level of pollutant emissions in the exhaust gas, which today is the most important criterion for assessing the quality of the engine. The paper presents a detailed analysis of the influence of physical properties of a mixture of diesel and biodiesel fuels on the output characteristics of the fuel injection system. The following parameters are shown: injection pressure, injection rate, the beginning and duration of injection, transformation of potential into kinetic energy of fuel and increase of energy losses in fuel injection system of various mixtures of diesel and biodiesel fuels. For the analysis of the results a self-developed computer program was used to simulate the injection process in the system. Computational results are verified using the experiment, for a few mixtures of diesel and biodiesel fuels. This paper presents the verification results for diesel fuel and biodiesel fuel in particular.

Characteristics and functionality of appetite-reducing thylakoid powders produced by three different drying processes.

Science.gov (United States)

Östbring, Karolina; Sjöholm, Ingegerd; Sörenson, Henrietta; Ekholm, Andrej; Erlanson-Albertsson, Charlotte; Rayner, Marilyn

2018-03-01

Thylakoids, a chloroplast membrane extracted from green leaves, are a promising functional ingredient with appetite-reducing properties via their lipase-inhibiting effect. Thylakoids in powder form have been evaluated in animal and human models, but no comprehensive study has been conducted on powder characteristics. The aim was to investigate the effects of different isolation methods and drying techniques (drum-drying, spray-drying, freeze-drying) on thylakoids' physicochemical and functional properties. Freeze-drying yielded thylakoid powders with the highest lipase-inhibiting capacity. We hypothesize that the specific macromolecular structures involved in lipase inhibition were degraded to different degrees by exposure to heat during spray-drying and drum-drying. We identified lightness (Hunter's L-value), greenness (Hunter's a-value), chlorophyll content and emulsifying capacity to be correlated to lipase-inhibiting capacity. Thus, to optimize the thylakoids functional properties, the internal membrane structure indicated by retained green colour should be preserved. This opens possibilities to use chlorophyll content as a marker for thylakoid functionality in screening processes during process optimization. Thylakoids are heat sensitive, and a mild drying technique should be used in industrial production. Strong links between physicochemical parameters and lipase inhibition capacity were found that can be used to predict functionality. The approach from this study can be applied towards production of standardized high-quality functional food ingredients. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Determination of properties of clean coal technology post-process residue

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Agnieszka Klupa

2016-01-01

Full Text Available This article presents the possibilities of using modern measuring devices to determine the properties of process residues (Polish acronym: UPP. UPP was taken from the combustion process from a power plant in Silesia. Determining the properties of UPP is the basis for making decisions about its practical application, for example, as a raw material to obtain useful products such as: pozzolan, cenosphere or zeolite, for which there is demand. The development of advanced technology and science has given rise to modern and precise research tools that contribute to the development of appropriate methods to assess the properties of post-process residue. For this study the following were used: scanning electron microscope with EDS microanalysis and an analyzer for particle size-, shape- and number- analysis. The study conducted confirms the effectiveness of SEM analysis to determine the properties of post-process residue from Clean Coal Technologies (CCT. The results obtained are an introduction to further research on the determination of properties of CCT post-process residue. Research to determine the properties of CCT post-process residue only began relatively recently.

Physical Properties for Lipids Based Process and Product Design

DEFF Research Database (Denmark)

Ana Perederic, Olivia; Kalakul, Sawitree; Sarup, Bent

Lipid processing covers several oil and fats technologies such as: edible oil production, biodieselproduction, oleochemicals (e.g.: food additives, detergents) and pharmaceutical product manufacturing. New demands regarding design and development of better products and more sustainable processes...... related to lipids technology, emerge according to consumers demanding improved product manufacturing from sustainable resources and new legislation regarding environmental safety [1]. Physical and thermodynamic property data and models for prediction of pure compound properties and mixtures properties...... involving lipids represent the basic and most important requirements for process product design, simulation and optimization. Experimentally measured values of involved compounds are desirable, but in most of the cases these are not available for all the compounds and properties needed. The lack...

Influence of hydrothermal processing on functional properties and grain morphology of finger millet.

Science.gov (United States)

Dharmaraj, Usha; Meera, M S; Reddy, S Yella; Malleshi, Nagappa G

2015-03-01

Finger millet was hydrothermally processed followed by decortication. Changes in color, diameter, density, sphericity, thermal and textural characteristics and also some of the functional properties of the millet along with the grain morphology of the kernels after hydrothermal processing and decortication were studied. It was observed that, the millet turned dark after hydrothermal processing and color improved over native millet after decortication. A slight decrease in grain diameter was observed but sphericity of the grains increased on decortication. The soft and fragile endosperm turned into a hard texture and grain hardness increased by about 6 fold. Hydrothermal processing increased solubility and swelling power of the millet at ambient temperature. Pasting profile indicated that, peak viscosity decreased significantly on hydrothermal processing and both hydrothermally processed and decorticated millet exhibited zero breakdown viscosity. Enthalpy was negative for hydrothermally processed millet and positive for decorticated grains. Microscopic studies revealed that the orderly structure of endosperm changed to a coherent mass after hydrothermal processing and the different layers of seed coat get fused with the endosperm.

Property Based Process and Product Synthesis and Design

DEFF Research Database (Denmark)

Eden, Mario Richard

2003-01-01

in terms of the constitutive (synthesis/design) variables instead of the process variables, thus providing the synthesis/design targets. The second reverse problem (reverse property prediction) solves the constitutive equations to identify unit operations, operating conditions and/or products by matching......This thesis describes the development of a general framework for solving process and product design problems. Targeting the desired performance of the system in a systematic manner relieves the iterative nature of conventional design techniques. Furthermore, conventional component based methods...... are not capable of handling problems, where the process or product objectives are driven by functionalities or properties rather than chemical constituency. The framework is meant to complement existing composition based methods by being able to handle property driven problems. By investigating the different...

Analysis of the influence of two different milling processes in the properties of precursor powder and [Beta]-TCP cement

International Nuclear Information System (INIS)

Cardoso, H.A.I.; Pereira, C.H.R.; Zavaglia, C.A.C.; Motisuke, M.

2011-01-01

There are several characteristics that put calcium phosphate cements in evidence, like its bioactivity and in vivo resorption. The influence of two milling processes in the morphological properties of the [beta]-tricalcium phosphate powder, [beta]-TCP, and in the mechanical properties of the cement were analyzed. The powder was obtained by solid state reaction of CaCO_3 and CaHPO_4 at 1050 ° C. It showed high phase purity and absence of toxic elements. The powder was processed in ball mill (A) and high-energy vibratory mill (B), with posterior analyze by SEM and particle size distribution. The powders showed different average and distribution of grain size. Finally, the cement obtained by the process (B) showed values of axial tensile strength significantly greater than that obtained by the process (A). The milling process (B) is much more efficient than the process (A). (author)

Review of thermo-physical properties, wetting and heat transfer characteristics of nanofluids and their applicability in industrial quench heat treatment.

Science.gov (United States)

Ramesh, Gopalan; Prabhu, Narayan Kotekar

2011-04-14

The success of quenching process during industrial heat treatment mainly depends on the heat transfer characteristics of the quenching medium. In the case of quenching, the scope for redesigning the system or operational parameters for enhancing the heat transfer is very much limited and the emphasis should be on designing quench media with enhanced heat transfer characteristics. Recent studies on nanofluids have shown that these fluids offer improved wetting and heat transfer characteristics. Further water-based nanofluids are environment friendly as compared to mineral oil quench media. These potential advantages have led to the development of nanofluid-based quench media for heat treatment practices. In this article, thermo-physical properties, wetting and boiling heat transfer characteristics of nanofluids are reviewed and discussed. The unique thermal and heat transfer characteristics of nanofluids would be extremely useful for exploiting them as quench media for industrial heat treatment.

Review of thermo-physical properties, wetting and heat transfer characteristics of nanofluids and their applicability in industrial quench heat treatment

Directory of Open Access Journals (Sweden)

Ramesh Gopalan

2011-01-01

Full Text Available Abstract The success of quenching process during industrial heat treatment mainly depends on the heat transfer characteristics of the quenching medium. In the case of quenching, the scope for redesigning the system or operational parameters for enhancing the heat transfer is very much limited and the emphasis should be on designing quench media with enhanced heat transfer characteristics. Recent studies on nanofluids have shown that these fluids offer improved wetting and heat transfer characteristics. Further water-based nanofluids are environment friendly as compared to mineral oil quench media. These potential advantages have led to the development of nanofluid-based quench media for heat treatment practices. In this article, thermo-physical properties, wetting and boiling heat transfer characteristics of nanofluids are reviewed and discussed. The unique thermal and heat transfer characteristics of nanofluids would be extremely useful for exploiting them as quench media for industrial heat treatment.

The Effect of Vibration during Friction Stir Welding on Corrosion Behavior, Mechanical Properties, and Machining Characteristics of Stir Zone

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Sajad Fouladi

2017-10-01

Full Text Available Different methods have been applied to refine various characteristics of the zone (or nugget obtained by friction stir welding (FSW. In the current research, joining components are vibrated normal to the weld line during FSW to refine the zone microstructure. This process is described as friction stir vibration welding (FSVW. The effect of FSVW on mechanical properties, corrosion behavior, and machining characteristics of the zone are investigated. Al5052 alloy specimens are welded using FSW and FSVW processes and their different characteristics are compared and discussed. The results show that the strength and ductility of the welded parts increase when the vibration is applied. The outcomes also show that corrosion resistance of the nugget for FSV-welded specimens is lower than FS welded samples, and machining force of the former specimens is higher than the latter ones. These are related to smaller grain size in the zone of FSV-welded specimens compared to FS welded parts. Smaller grain size leads to a greater volume fraction of grain boundaries and, correspondingly, higher strength and hardness, as well as lower corrosion resistance.

Justification of the Production Process of Pressed Wood and Study of its Properties

Science.gov (United States)

Polilov, A. N.; Dornyak, O. R.; Shamaev, V. A.; Rumachik, M. M.

2018-05-01

Results of a numerical analysis of the stress-strain state of wood during its pressing in different symmetry directions of the anisotropic material are presented. It is shown that the anisotropy of mechanical properties of wood is an important factor determining both the structural characteristics of the porous system and its strength. A mathematical modeling of the process of pressing wood as a three-phase anisotropic rheologically complex capillary-porous system allows one to predict parameters of the resulting wood composite. The compressed wood obtained by the production modes developed has a tensile strength eight times greater than that of the natural one, which is comparable to the strength of the St3 steel, but its specific strength is higher than that of the St45 steel. Compression and impregnation of softwood species with an aqueous solution of carbamide allows one to harden them. This kind of treatment endows the wood with enhanced strength characteristics comparable to the characteristics of the St3 steel. The special features of tensile tests used to estimate the elastic modulus and strength characteristics of such materials are considered. Data obtained by different testing methods are correlated, and characteristics of the strengthened wood and some brends of steel are compared.

A Review on Biomass Torrefaction Process and Product Properties

Energy Technology Data Exchange (ETDEWEB)

Jaya Shankar Tumuluru; Shahab Sokhansanj; Christopher T. Wright; J. Richard Hess; Richard D. Boardman

2011-08-01

Biomass Torrefaction is gaining attention as an important preprocessing step to improve the quality of biomass in terms of physical properties and chemical composition. Torrefaction is a slow heating of biomass in an inert or reduced environment to a maximum temperature of approximately 300 C. Torrefaction can also be defined as a group of products resulting from the partially controlled and isothermal pyrolysis of biomass occurring in a temperature range of 200-280 C. Thus, the process can be called a mild pyrolysis as it occurs at the lower temperature range of the pyrolysis process. At the end of the torrefaction process, a solid uniform product with lower moisture content and higher energy content than raw biomass is produced. Most of the smoke-producing compounds and other volatiles are removed during torrefaction, which produces a final product that will have a lower mass but a higher heating value. The present review work looks into (a) torrefaction process and different products produced during the process and (b) solid torrefied material properties which include: (i) physical properties like moisture content, density, grindability, particle size distribution and particle surface area and pelletability; (ii) chemical properties like proximate and ultimate composition; and (iii) storage properties like off-gassing and spontaneous combustion.

An experimental bioactive dental ceramic for metal-ceramic restorations: Textural characteristics and investigation of the mechanical properties.

Science.gov (United States)

Goudouri, Ourania-Menti; Kontonasaki, Eleana; Papadopoulou, Lambrini; Manda, Marianthi; Kavouras, Panagiotis; Triantafyllidis, Konstantinos S; Stefanidou, Maria; Koidis, Petros; Paraskevopoulos, Konstantinos M

2017-02-01

The aim of this study was the evaluation of the textural characteristics of an experimental sol-gel derived feldspathic dental ceramic, which has already been proven bioactive and the investigation of its flexural strength through Weibull Statistical Analysis. The null hypothesis was that the flexural strength of the experimental and the commercial dental ceramic would be of the same order, resulting in a dental ceramic with apatite forming ability and adequate mechanical integrity. Although the flexural strength of the experimental ceramics was not statistically significant different compared to the commercial one, the amount of blind pores due to processing was greater. The textural characteristics of the experimental ceramic were in accordance with the standard low porosity levels reported for dental ceramics used for fixed prosthetic restorations. Feldspathic dental ceramics with typical textural characteristics and advanced mechanical properties as well as enhanced apatite forming ability can be synthesized through the sol-gel method. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Newest Laser Processing

International Nuclear Information System (INIS)

Lee, Baek Yeon

2007-01-01

This book mentions laser processing with laser principle, laser history, laser beam property, laser kinds, foundation of laser processing such as laser oscillation, characteristic of laser processing, laser for processing and its characteristic, processing of laser hole including conception of processing of laser hole and each material, and hole processing of metal material, cut of laser, reality of cut, laser welding, laser surface hardening, application case of special processing and safety measurement of laser.

Effect of extrusion processing on the microstructure, mechanical properties, biocorrosion properties and antibacterial properties of Ti-Cu sintered alloys.

Science.gov (United States)

Zhang, Erlin; Li, Shengyi; Ren, Jing; Zhang, Lan; Han, Yong

2016-12-01

Ti-Cu sintered alloys, Ti-Cu(S) alloy, have exhibited good anticorrosion resistance and strong antibacterial properties, but low ductility in previous study. In this paper, Ti-Cu(S) alloys were subjected to extrusion processing in order to improve the comprehensive property. The phase constitute, microstructure, mechanical property, biocorrosion property and antibacterial activity of the extruded alloys, Ti-Cu(E), were investigated in comparison with Ti-Cu(S) by X-ray diffraction (XRD), optical microscopy (OM), scanning electronic microscopy (SEM) with energy disperse spectroscopy (EDS), mechanical testing, electrochemical testing and plate-count method in order to reveal the effect of the extrusion process. XRD, OM and SEM results showed that the extrusion process did not change the phase constitute but refined the grain size and Ti2Cu particle significantly. Ti-Cu(E) alloys exhibited higher hardness and compressive yield strength than Ti-Cu(S) alloys due to the fine grain and Ti2Cu particles. With the consideration of the total compressive strain, it was suggested that the extrusion process could improve the ductility of Ti-Cu alloy(S) alloys. Electrochemical results have indicated that the extrusion process improved the corrosion resistance of Ti-Cu(S) alloys. Plate-count method displayed that both Ti-Cu(S) and Ti-Cu(E) exhibited strong antibacterial activity (>99%) against S. aureus. All these results demonstrated that hot forming processing, such as the extrusion in this study, refined the microstructure and densified the alloy, in turn improved the ductility and strength as well as anticorrosion properties without reduction in antibacterial properties. Copyright © 2016 Elsevier B.V. All rights reserved.

[Constructivism: a characteristic of the psychic process].

Science.gov (United States)

Ruiz, R H

1995-05-01

Constructivism, more than a posture or a school concept, is a specific feature of the psychic process. The term "specific" needs to be understood taking into account two senses. On the one hand, as a first sense, one must consider it as something inherent to the psychic process. On the other, as a second sense, it means that constructivism in the psychic process has distinctive characteristics: and this make it differ from the concept of constructivism applied in other fields. The fact of considering the psychism as a "construction" lets explain those mental productions such as art and science; as well as madness and crime: possibilities and risks of that construction.

Properties and mesostructural characteristics of linen fiber reinforced self-compacting concrete in slender columns

Directory of Open Access Journals (Sweden)

Sabry A. Ahmed

2013-06-01

Full Text Available In this study the linen fibers were used to reinforce self-compacting concrete (SCC with 2 and 4 kg/m3 contents; then their effects on the fresh and hardened properties of SCC were investigated. Furthermore, three circular slender columns were cast using both plain and linen fiber reinforced (LFR SCC in order to study the variations of hardened properties and mesostructural characteristics along the columns height. The addition of linen fibers to SCC reduced its workability and affected its self-compacting characteristics in a manner depending on the fiber content. Also, noticeable improvement in mechanical properties and slight reduction in unit weight and UPV were recorded. The hardened properties did not vary significantly along the height of columns, however, lower values were observed at the upper end of columns. The aggregate distribution was slightly more homogenous in case of LFRSCC, and the variation of fiber density along the height of columns was relatively high.

Progress on matrix SiC processing and properties for fully ceramic microencapsulated fuel form

International Nuclear Information System (INIS)

Terrani, K.A.; Kiggans, J.O.; Silva, C.M.; Shih, C.; Katoh, Y.; Snead, L.L.

2015-01-01

The consolidation mechanism and resulting properties of the silicon carbide (SiC) matrix of fully ceramic microencapsulated (FCM) fuel form are discussed. The matrix is produced via the nano-infiltration transient eutectic-forming (NITE) process. Coefficient of thermal expansion, thermal conductivity, and strength characteristics of this SiC matrix have been characterized in the unirradiated state. An ad hoc methodology for estimation of thermal conductivity of the neutron-irradiated NITE–SiC matrix is also provided to aid fuel performance modeling efforts specific to this concept. Finally, specific processing methods developed for production of an optimal and reliable fuel form using this process are summarized. These various sections collectively report the progress made to date on production of optimal FCM fuel form to enable its application in light water and advanced reactors

Scaling characteristics of one-dimensional fractional diffusion processes in the presence of power-law distributed random noise.

Science.gov (United States)

Nezhadhaghighi, Mohsen Ghasemi

2017-08-01

Here, we present results of numerical simulations and the scaling characteristics of one-dimensional random fluctuations with heavy-tailed probability distribution functions. Assuming that the distribution function of the random fluctuations obeys Lévy statistics with a power-law scaling exponent, we investigate the fractional diffusion equation in the presence of μ-stable Lévy noise. We study the scaling properties of the global width and two-point correlation functions and then compare the analytical and numerical results for the growth exponent β and the roughness exponent α. We also investigate the fractional Fokker-Planck equation for heavy-tailed random fluctuations. We show that the fractional diffusion processes in the presence of μ-stable Lévy noise display special scaling properties in the probability distribution function (PDF). Finally, we numerically study the scaling properties of the heavy-tailed random fluctuations by using the diffusion entropy analysis. This method is based on the evaluation of the Shannon entropy of the PDF generated by the random fluctuations, rather than on the measurement of the global width of the process. We apply the diffusion entropy analysis to extract the growth exponent β and to confirm the validity of our numerical analysis.

Scaling characteristics of one-dimensional fractional diffusion processes in the presence of power-law distributed random noise

Science.gov (United States)

Nezhadhaghighi, Mohsen Ghasemi

2017-08-01

Here, we present results of numerical simulations and the scaling characteristics of one-dimensional random fluctuations with heavy-tailed probability distribution functions. Assuming that the distribution function of the random fluctuations obeys Lévy statistics with a power-law scaling exponent, we investigate the fractional diffusion equation in the presence of μ -stable Lévy noise. We study the scaling properties of the global width and two-point correlation functions and then compare the analytical and numerical results for the growth exponent β and the roughness exponent α . We also investigate the fractional Fokker-Planck equation for heavy-tailed random fluctuations. We show that the fractional diffusion processes in the presence of μ -stable Lévy noise display special scaling properties in the probability distribution function (PDF). Finally, we numerically study the scaling properties of the heavy-tailed random fluctuations by using the diffusion entropy analysis. This method is based on the evaluation of the Shannon entropy of the PDF generated by the random fluctuations, rather than on the measurement of the global width of the process. We apply the diffusion entropy analysis to extract the growth exponent β and to confirm the validity of our numerical analysis.

Effect of UHT processing and storage conditions on physico-chemical characteristics of buffalo skim milk

International Nuclear Information System (INIS)

Hussain, I.

2011-01-01

The obtained results indicated that physico-chemical and nutritional changes in UHT processed buffalo skimmed milk were more pronounced at 45 deg. C than 25 deg. C and 10 deg. C. Duration of storage adversely affected the chemical and nutritional quality of processed milk. A slight decrease in pH, total ash and lactose contents, was observed, whereas acidity was increased on the mentioned storage conditions. Total nitrogen and casein nitrogen contents gradually decreased during storage, whereas non-casein nitrogen (NCN) and non-protein nitrogen (NPN) increased to a great extent in samples stored at higher temperatures. A significant increase in hydroxyl methyl furfural (HMF) values occurred in UHT processed buffalo skim milk at 25 deg. C and 45 deg. C after of 90 days storage. Storage at high temperature (45 deg. C) caused undesirable effects on sensory properties, general quality characteristics and acceptability of UHT buffalo skimmed milk. (author)

Characteristics of the Audit Processes for Distributed Informatics Systems

Directory of Open Access Journals (Sweden)

Marius POPA

2009-01-01

Full Text Available The paper contains issues regarding: main characteristics and examples of the distributed informatics systems and main difference categories among them, concepts, principles, techniques and fields for auditing the distributed informatics systems, concepts and classes of the standard term, characteristics of this one, examples of standards, guidelines, procedures and controls for auditing the distributed informatics systems. The distributed informatics systems are characterized by the following issues: development process, resources, implemented functionalities, architectures, system classes, particularities. The audit framework has two sides: the audit process and auditors. The audit process must be led in accordance with the standard specifications in the IT&C field. The auditors must meet the ethical principles and they must have a high-level of professional skills and competence in IT&C field.

Effects of gamma irradiation on physical-chemical properties and dewatering characteristics of sludges

International Nuclear Information System (INIS)

Groneman, A.F.

1976-01-01

Separation of solids from liquids is a paramount operation in the processes applied in treating sewage and waste waters. Therfore, studies were undertaken to investigate effects of gamma irradiation on the physical-chemical properties of sludges and the de-watering characteristics of anaerobically digested sludge and aerobically activated sludge. A dose of 300 krad reduced the specific resistance of anaerobically digested sludges from 33 x 10 sec 2 /g to approximately 10 x 10 9 sec 2 /g. This conditioning effect was little influenced by the presence of oxygen or nitrogen. Pasteurization increased the specific resistance to filtration up to 48 x 10 9 sec 2 /g. Dewatering characteristics of raw sludge were not affected by irradiation in the presence of oxygen but a slight conditioning effect was noticed when the sludge was irradiated under deaerated conditions. Experimental evidence indicated that gamma irradiation detached organic substances from the sludge flocks resulting in a decrease of the specific resistance and an increase in the Total Organic Carbon (TOC) and the Chemical Oxygen Demand (COD) in the filtrates. Elutriation reduced but did not eliminate the conditioning effect of gamma irradiation. (author)

ERP differences between processing of physical characteristics and personality attributes

Science.gov (United States)

2012-01-01

Background Limited data from behavioral and brain-imaging studies indicate that personality traits and physical characteristics are processed differently by the brain. Additionally, electrophysiological results of studies comparing the processing of positive and negative words have produced mixed results. It is therefore not clear how physical and personality attributes with emotional valence (i.e., positive and negative valence) are processed. Thus, this study aimed to examine the neural activity associated with words describing personality traits and physical characteristics with positive or negative emotional valence using Event Related Potentials (ERPs). Methods A sample of 15 healthy adults (7 men, 8 women) participated in a computerized word categorization task. Participants were asked to categorize visual word stimuli as physical characteristics or personality traits, while ERPs were recorded synchronously. Results Behavioral reaction times to negative physical stimuli were shorter compared to negative personality words, however reaction times did not significantly differ for positive stimuli. Electrophysiological results showed that personality stimuli elicited larger P2 and LPC (Late Positive Component) amplitudes compared to physical stimuli, regardless of negative or positive valence. Moreover, negative as compared with positive stimuli elicited larger P2 and LPC amplitudes. Conclusion Personality and physical stimuli were processed differently regardless of positive or negative valence. These findings suggest that personality traits and physical characteristics are differentially classified and are associated with different motivational significance. PMID:22967478

Water Transfer Characteristics during Methane Hydrate Formation Processes in Layered Media

Directory of Open Access Journals (Sweden)

Yousheng Deng

2011-08-01

Full Text Available Gas hydrate formation processes in porous media are always accompanied by water transfer. To study the transfer characteristics comprehensively, two kinds of layered media consisting of coarse sand and loess were used to form methane hydrate in them. An apparatus with three PF-meter sensors detecting water content and temperature changes in media during the formation processes was applied to study the water transfer characteristics. It was experimentally observed that the hydrate formation configurations in different layered media were similar; however, the water transfer characteristics and water conversion ratios were different.

Statistical properties of several models of fractional random point processes

Science.gov (United States)

Bendjaballah, C.

2011-08-01

Statistical properties of several models of fractional random point processes have been analyzed from the counting and time interval statistics points of view. Based on the criterion of the reduced variance, it is seen that such processes exhibit nonclassical properties. The conditions for these processes to be treated as conditional Poisson processes are examined. Numerical simulations illustrate part of the theoretical calculations.

Processing and properties of Nb-Ti-based alloys

International Nuclear Information System (INIS)

Sikka, V.K.; Viswanathan, S.

1992-01-01

The processing characteristics, tensile properties, and oxidation response of two Nb-Ti-Al-Cr alloys were investigated. One creep test at 650 C and 172 MPa was conducted on the base alloy which contained 40Nb-40Ti-10Al-10Cr. A second alloy was modified with 0.11 at. % carbon and 0.07 at. % yttrium. Alloys were arc melted in a chamber backfilled with argon, drop cast into a water-cooled copper mold, and cold rolled to obtain a 0.8-mm sheet. The sheet was annealed at 1,100 C for 0.5 h. Longitudinal tensile specimens and oxidation specimens were obtained for both the base alloy and the modified alloy. Tensile properties were obtained for the base alloy at room temperature, 400, 600, 700, 800, 900, and 1,000 C, and for the modified alloy at room temperature, 400, 600, 700, and 800 C. Oxidation tests on the base alloy and modified alloy, as measured by weight change, were carried out at 600, 700, 800, and 900 C. Both the base alloy and the modified alloy were extremely ductile and were cold rolled to the final sheet thickness of 0.8 mm without an intermediate anneal. The modified alloy exhibited some edge cracking during cold during cold rolling. Both alloys recrystallized at the end of a 0.5-h annealing treatment. The alloys exhibited moderate strength and oxidation resistance below 600 C, similar to the results of alloys reported in the literature

Reflow Process Parameters Analysis and Reliability Prediction Considering Multiple Characteristic Values

Directory of Open Access Journals (Sweden)

Guo Yu

2016-01-01

Full Text Available As a major step surface mount technology, reflow process is the key factor affecting the quality of the final product. The setting parameters and characteristic value of temperature curve shows a nonlinear relationship. So parameter impacts on characteristic values are analyzed and the parameters adjustment process based on orthogonal experiment is proposed in the paper. First, setting parameters are determined and the orthogonal test is designed according to production conditions. Then each characteristic value for temperature profile is calculated. Further, multi-index orthogonal experiment is analyzed for acquiring the setting parameters which impacts the PCBA product quality greater. Finally, reliability prediction is carried out considering the main influencing parameters for providing a theoretical basis of parameters adjustment and product quality evaluation in engineering process.

Analyzing Properties of Stochastic Business Processes By Model Checking

DEFF Research Database (Denmark)

Herbert, Luke Thomas; Sharp, Robin

2013-01-01

This chapter presents an approach to precise formal analysis of business processes with stochastic properties. The method presented here allows for both qualitative and quantitative properties to be individually analyzed at design time without requiring a full specification. This provides...... an effective means to explore possible designs for a business process and to debug any flaws....

A general overview of support materials for enzyme immobilization: Characteristics, properties, practical utility

DEFF Research Database (Denmark)

Zdarta, Jakub; Meyer, Anne S.; Jesionowski, Teofil

2018-01-01

on the properties of the produced catalytic system. A large variety of inorganic and organic as well as hybrid and composite materials may be used as stable and efficient supports for biocatalysts. This review provides a general overview of the characteristics and properties of the materials applied for enzyme...... immobilization. For the purposes of this literature study, support materials are divided into two main groups, called Classic and New materials. The review will be useful in selection of appropriate support materials with tailored properties for the production of highly effective biocatalytic systems for use...

Processing hexavalent uranium gels and their properties

International Nuclear Information System (INIS)

Landspersky, H.; Benadik, A.; Spitzer, Z.

1980-01-01

The properties of xerogels of ammonium polyuranate prepared by various drying procedures were studied. The individual drying procedures affect differently both the chemical structure of the material (its composition) and the physicochemical properties of the final product (specific surface area, porosity). In addition, the physicochemical properties of xerogels depend on the properties of the starting material, i.e., on the type of the initial gel. The physicochemical properties of xerogels, in particular their porosity, are in turn relevant for their subsequent high-temperature processing. The porous structure is essential for thermal treatment. The structure of xerogels obtained by distillation procedures is affected both by the conditions of azeotropic distillation and by the medium employed. By judicious selection of these two variables it is possible to prepare materials with different pore size distributions. (author)

Physical properties, evaporation and combustion characteristics of nanofluid-type fuels

OpenAIRE

Tanvir, Saad

2016-01-01

Nanofluids are liquids with stable suspension of nanoparticles. Limited studies in the past have shown that both energetic and catalytic nanoparticles once mixed with traditional liquid fuels can be advantageous in combustion applications, e.g., increased energy density and shortened ignition delay. Contradictions in existing literature, scarcity of experimental data and lack of understanding on how the added nanoparticles affect the physical properties as well as combustion characteristics o...

Process, structure, property and applications of metallic glasses

Directory of Open Access Journals (Sweden)

B. Geetha Priyadarshini

2016-07-01

Full Text Available Metallic glasses (MGs are gaining immense technological significance due to their unique structure-property relationship with renewed interest in diverse field of applications including biomedical implants, commercial products, machinery parts, and micro-electro-mechanical systems (MEMS. Various processing routes have been adopted to fabricate MGs with short-range ordering which is believed to be the genesis of unique structure. Understanding the structure of these unique materials is a long-standing unsolved mystery. Unlike crystalline counterpart, the outstanding properties of metallic glasses owing to the absence of grain boundaries is reported to exhibit high hardness, excellent strength, high elastic strain, and anti-corrosion properties. The combination of these remarkable properties would significantly contribute to improvement of performance and reliability of these materials when incorporated as bio-implants. The nucleation and growth of metallic glasses is driven by thermodynamics and kinetics in non-equilibrium conditions. This comprehensive review article discusses the various attributes of metallic glasses with an aim to understand the fundamentals of relationship process-structure-property existing in such unique class of material.

WOOD PROPERTIES AND EFFECT OF WOOD PROPERTIES ON THE WOOD FINISHING

Directory of Open Access Journals (Sweden)

Abdulkadir Malkoçoğlu

2006-04-01

Full Text Available Wood is basic raw material for furniture and joinery industries with wood structures. Wood is a biological material that has widely different properties depending on species, geographic area where the tree grew, the growth condition, size of the tree at harvest, sawing, and other manufacturing processes. Wood properties have been characterized within two groups as natural and manufacturing factors that effects finishing performance. Grow rate, density, knots, moisture content, extractives and juvenile wood are natural characteristics. Grain orientation, texture, drying and performance expectations are manufacturing characteristics. In this review, the effects of natural and manufacturing characteristics are discussed on the surface finishing performance of wood.

An experimental evaluation of alarm processing and display characteristics

International Nuclear Information System (INIS)

O'Hara, J.; Brown, W.; Hallbert, B.; Skraaning, G.Jr.; Persensky, J.; Wachtel, J.

1998-01-01

This paper describes a research program sponsored by the U.S. Nuclear Regulatory Commission to address the human factors engineering (HFE) aspects of nuclear power plant alarm systems. The overall objective of the program is to develop HFE review guidance for advanced alarm systems. As part of this program, guidance has been developed based on a broad base of technical and research literature. In the course of guidance development, aspects of alarm system design for which the technical basis was insufficient to support complete guidance development were identified. The primary purpose of the research reported in this paper was to evaluate the effects of three of these alarm system design characteristics on operator performance in order to contribute to the understanding of potential safety issues and to provide data to support the development of design review guidance in these areas. Three alarm system design characteristics studied were (1) alarm processing (degree of alarm reduction), (2) alarm availability (dynamic prioritization and suppression), and (3) alarm display (a dedicated tile format, a mixed tile and message list format, and a format in which alarm information is integrated into the process displays). A secondary purpose was to provide confirmatory evidence of selected alarm system guidance developed in an earlier phase of the project. The alarm characteristics were combined into eight separate experimental conditions. Six, two-person crews of professional nuclear power plant operators participated in the study. Following training, each crew completed 16 test trials which consisted of two trials in each of the eight experimental conditions (one with a low-complexity scenario and one with a high-complexity scenario). Measures of process performance. operator task performance, situation awareness, and workload were obtained. In addition. operator opinions and evaluations of the alarm processing and display conditions were collected. Numerous strengths

Superconducting properties and uniaxial strain characteristics of Nb3Sn fiber-reinforced superconductors with tantalum reinforcement fibers

International Nuclear Information System (INIS)

Arai, Kazuaki; Umeda, Masaichi; Agatsuma, Koh; Tateishi, Hiroshi

1998-01-01

We have been developing fiber-reinforced superconductors (FRS) for high-field and large-scale magnets. Tungsten fibers have been selected as the reinforcement fiber for FRS so far because tungsten has the highest elastic modulus of approximately 400 GPa which can minimize the strain from electromagnetic force. The preparation process of FRS consists of sputtering deposition and heat treatment because it may be difficult to apply drawing methods to materials of high-elastic modulus such as tungsten. Tantalum has high elastic modulus of 178 GPa and its thermal expansion coefficient that is closer to that of Nb 3 Sn than tungsten's, which means prestrain in Nb 3 Sn in FRS is reduced by adopting tantalum fibers. Tantalum has been used as barriers between bronze and copper in conventional Nb 3 Sn superconductors which are usually prepared with drawing process despite of the tantalum's high elastic modulus. That implies drawing process may be applied to prepare FRS with tantalum reinforcement fibers. In this paper, FRS using tantalum fibers prepared with sputtering process are described with making comparison with FRS of tungsten to clarify the basic properties of FRS using tantalum fibers. Depth profiles in Nb 3 Sn layer in FRS were measured to examine reaction between superconducting layers and reinforcement fibers. Superconducting properties including strain and stress characteristics were shown. Those data will contribute to design of FRS using tantalum reinforcement fibers with adopts the drawing processes. (author)

Polypeptide binding properties of the chaperone calreticulin

DEFF Research Database (Denmark)

Jørgensen, C S; Heegaard, N H; Holm, A

2000-01-01

Calreticulin is a highly conserved eukaryotic ubiquitious protein located mainly in the endoplasmic reticulum. Two major characteristics of calreticulin are its chaperone activity and its lectin properties, but its precise function in intracellular protein and peptide processing remains to be elu......Calreticulin is a highly conserved eukaryotic ubiquitious protein located mainly in the endoplasmic reticulum. Two major characteristics of calreticulin are its chaperone activity and its lectin properties, but its precise function in intracellular protein and peptide processing remains...

Property Modelling for Applications in Chemical Product and Process Design

DEFF Research Database (Denmark)

Gani, Rafiqul

such as database, property model library, model parameter regression, and, property-model based product-process design will be presented. The database contains pure component and mixture data for a wide range of organic chemicals. The property models are based on the combined group contribution and atom...... is missing, the atom connectivity based model is employed to predict the missing group interaction. In this way, a wide application range of the property modeling tool is ensured. Based on the property models, targeted computer-aided techniques have been developed for design and analysis of organic chemicals......, polymers, mixtures as well as separation processes. The presentation will highlight the framework (ICAS software) for property modeling, the property models and issues such as prediction accuracy, flexibility, maintenance and updating of the database. Also, application issues related to the use of property...

Mechanical properties and cell-culture characteristics of a polycaprolactone kagome-structure scaffold fabricated by a precision extruding deposition system.

Science.gov (United States)

Lee, Se-Hwan; Cho, Yong Sang; Hong, Myoung Wha; Lee, Bu-Kyu; Park, Yongdoo; Park, Sang-Hyug; Kim, Young Yul; Cho, Young-Sam

2017-09-13

To enhance the mechanical properties of three-dimensional (3D) scaffolds used for bone regeneration in tissue engineering, many researchers have studied their structure and chemistry. In the structural engineering field, the kagome structure has been known to have an excellent relative strength. In this study, to enhance the mechanical properties of a synthetic polymer scaffold used for tissue engineering, we applied the 3D kagome structure to a porous scaffold for bone regeneration. Prior to fabricating the biocompatible-polymer scaffold, the ideal kagome structure, which was manufactured by a 3D printer of the digital light processing type, was compared with a grid-structure, which was used as the control group, using a compressive experiment. A polycaprolactone (PCL) kagome-structure scaffold was successfully fabricated by additive manufacturing using a 3D printer with a precision extruding deposition head. To assess the physical characteristics of the fabricated PCL-kagome-structure scaffold, we analyzed its porosity, pore size, morphological structure, surface roughness, compressive stiffness, and mechanical bending properties. The results showed that, the mechanical properties of proposed kagome-structure scaffold were superior to those of a grid-structure scaffold. Moreover, Sarcoma osteogenic (Saos-2) cells were used to evaluate the characteristics of in vitro cell proliferation. We carried out cell counting kit-8 (CCK-8) and DNA contents assays. Consequently, the cell proliferation of the kagome-structure scaffold was increased; this could be because the surface roughness of the kagome-structure scaffold enhances initial cell attachment.

Properties of supersymmetric particles and processes

International Nuclear Information System (INIS)

Barnett, R.M.

1986-01-01

The motivations for experimental searches for supersymmetric particles are discussed. The role of R-parity in these searches is described. The production and decay characteristics of each class of supersymmetric particles are investigated in the context of both e+e- and hadron machines. There is a detailed presentation of a sample calculation of a supersymmetric process. Emphasis is given to the signatures for detection of supersymmetric particles and processes. The current limits for supersymmetric particles are given. 125 refs., 50 figs

Differences in fundamental and functional properties of HPMC co-processed fillers prepared by fluid-bed coating and spray drying.

Science.gov (United States)

Dong, QianQian; Zhou, MiaoMiao; Lin, Xiao; Shen, Lan; Feng, Yi

2018-07-01

This study aimed to develop novel co-processed tablet fillers based on the principle of particle engineering for direct compaction and to compare the characteristics of co-processed products obtained by fluid-bed coating and co-spray drying, respectively. Water-soluble mannitol and water-insoluble calcium carbonate were selected as representative fillers for this study. Hydroxypropyl methylcellulose (HPMC), serving as a surface property modifier, was distributed on the surface of primary filler particles via the two co-processing methods. Both fundamental and functional properties of the products were comparatively investigated. The results showed that functional properties of the fillers, like flowability, compactibility, and drug-loading capacity, were effectively improved by both co-processing methods. However, fluid-bed coating showed greater advantages over co-spray drying in some aspects, which was mainly attributed to the remarkable differences in some fundamental properties of co-processed powders, like particle size, surface topology, and particle structure. For example, the more irregular surface and porous structure induced by fluid-bed coating could contribute to better compaction properties and lower lubricant sensitivity due to the increasing contact area and mechanical interlocking between particles under pressure. More effective surface distribution of HPMC during fluid-bed coating was also a contributor. In addition, such a porous agglomerate structure could also reduce the separation of drug and excipients after mixing, resulting in the improvement in drug loading capacity and tablet uniformity. In summary, fluid-bed coating appears to be more promising for co-processing than spray drying in some aspects, and co-processed excipients produced by it have a great prospect for further investigations and development. Copyright © 2018 Elsevier B.V. All rights reserved.

Rheological properties of biscuit dough from different cultivars, and relationship to baking characteristics

DEFF Research Database (Denmark)

Pedersen, L.; Kaack, K.; Bergsøe, M.N.

2004-01-01

differences in structural properties with genetic control. Multivariate regression of flour physiochemical, dough theological, and biscuit baking characteristics showed that a decrease in biscuit length was correlated under several theological parameters, including phase angle delta, Farinograph and creep......Rheological properties of semi-sweet biscuit doughs from eight wheat cultivars were studied, and related to the dimensional changes of biscuits after cutting and baking. The tested cultivars were selected in order to represent a wide diversity in biscuit baking performance, and were grown with low...... recovery parameters. Sedimentation value was the only physiochernical flour characteristic with considerable influence on the model. Validation of the partial least squares-model including all samples from the 3 years gave only a weak correlation (r = 0.58), whereas when each single year was evaluated...

Synthesis and field emission properties of carbon nanotubes grown in ethanol flame based on a photoresist-assisted catalyst annealing process

International Nuclear Information System (INIS)

Yang Xiaoxia; Fang Guojia; Liu Nishuang; Wang Chong; Zheng Qiao; Zhou Hai; Zhao Dongshan; Long Hao; Liu Yuping; Zhao Xingzhong

2009-01-01

Carbon nanotubes (CNTs) have been grown directly on a Si substrate without a diffusion barrier in ethanol diffusion flame using Ni as the catalyst after a photoresist-assisted catalyst annealing process. The growth mechanism of as-synthesized CNTs is confirmed by scanning electron microscopy, high resolution transmission-electron microscopy and energy-dispersive spectroscopy. The photoresist is the key for the formation of active catalyst particles during annealing process, which then result in the growth of CNTs. The catalyst annealing temperature has been found to affect the morphologies and field electron emission properties of CNTs significantly. The field emission properties of as-grown CNTs are investigated with a diode structure and the obtained CNTs exhibit enhanced characteristics. This technique will be applicable to a low-cost fabrication process of electron-emitter arrays.

Chemical and physicochemical characteristics changes during passion fruit juice processing

Directory of Open Access Journals (Sweden)

Aline Gurgel Fernandes

2011-09-01

Full Text Available Passion fruit is widely consumed due to its pleasant flavour and aroma acidity, and it is considered very important a source of minerals and vitamins. It is used in many products such as ice-cream, mousses and, especially, juices. However, the processing of passion fruit juice may modify the composition and biodisponibility of the bioactive compounds. Investigations of the effects of processing on nutritional components in tropical juices are scarce. Frequently, only losses of vitamin C are evaluated. The objective of this paper is to investigate how some operations of passion fruit juice processing (formulation/homogeneization/thermal treatment affect this product's chemical and physicochemical characteristics. The results showed that the chemical and physicochemical characteristics are little affected by the processing although a reduction in vitamin C contents and anthocyanin, large quantities of carotenoids was verified even after the pasteurization stage.

High temperature properties and processes in ceramics: thermomigration

International Nuclear Information System (INIS)

1978-01-01

The focus of this program is on the effects of large temperature gradients on the transport processes, the defect structure and resulting physical properties of ceramics. In particular, the transport of ions due to thermal gradients is one of the least understood phenomenon in materials science and is presumably based on fundamental understanding of thermodynamics, atomistic kinetic processes, and structure-property relationships. The purpose of this research is to systematically consider each of the elements of atomic transport due to driving forces other than composition gradients in a model ceramic system

Metallic nanoshells with semiconductor cores: optical characteristics modified by core medium properties.

Science.gov (United States)

Bardhan, Rizia; Grady, Nathaniel K; Ali, Tamer; Halas, Naomi J

2010-10-26

It is well-known that the geometry of a nanoshell controls the resonance frequencies of its plasmon modes; however, the properties of the core material also strongly influence its optical properties. Here we report the synthesis of Au nanoshells with semiconductor cores of cuprous oxide and examine their optical characteristics. This material system allows us to systematically examine the role of core material on nanoshell optical properties, comparing Cu(2)O core nanoshells (ε(c) ∼ 7) to lower core dielectric constant SiO(2) core nanoshells (ε(c) = 2) and higher dielectric constant mixed valency iron oxide nanoshells (ε(c) = 12). Increasing the core dielectric constant increases nanoparticle absorption efficiency, reduces plasmon line width, and modifies plasmon energies. Modifying the core medium provides an additional means of tailoring both the near- and far-field optical properties in this unique nanoparticle system.

Structural properties of reflected Lévy processes

DEFF Research Database (Denmark)

Andersen, Lars Nørvang; Mandjes, Michel

This paper considers a number of structural properties of reflected Lévy processes, where both one-sided reflection (at 0) and two-sided reflection (at both 0 and K > 0) are examined. With Vt being the position of the reflected process at time t, we focus on the analysis of ζ(t) := EVt and ξ(t) :...

SOFC: Processes and characteristics of ageing behaviour

International Nuclear Information System (INIS)

Gerganov, T.; Grigorov, S.; Kozhukharov, S.

2005-01-01

The high-temperature solid oxide fuel cell (SOFC) is convenient for the environmental friendly and efficient conversion of chemical into electric energy. During the last decade the development of planar SOFC stacks with metallic interconnects has made considerable progress in both size and power density. The improvement of durability in long-term operation of planar SOFC components is one of the main fields for stationary applications. Ageing of stacks can be caused by various processes, e.g. corrosion of metallic plates, degradation of ceramic parts and chemical interactions on electrodes/electrolyte or interconnect/electrode interface. Namely, these processes are object of the overview in the present work. The most important characteristics of ageing behavior are subjected to analysis and discussion, as well. Moreover a correlation between ageing process and single cell performance will be given

Mechanical properties of ceramic structures based on Triply Periodic Minimal Surface (TPMS) processed by 3D printing

Science.gov (United States)

Restrepo, S.; Ocampo, S.; Ramírez, J. A.; Paucar, C.; García, C.

2017-12-01

Repairing tissues and organs has been the main goal of surgical procedures. Since the 1990s, the main goal of tissue engineering has been reparation, using porous scaffolds that serve as a three-dimensional template for the initial fixation of cells and subsequent tissue formation both in vitro and in vivo. A scaffold must have specific characteristics of porosity, interconnectivity, surface area, pore volume, surface tortuosity, permeability and mechanical properties, which makes its design, manufacturing and characterization a complex process. Inspired by nature, triply periodic minimal surfaces (TPMS) have emerged as an alternative for the manufacture of porous pieces with design requirements, such as scaffolds for tissue repair. In the present work, we used the technique of 3D printing to obtain ceramic structures with Gyroid, Schwarz Primitive and Schwarz Diamond Surfaces shapes, three TPMS that fulfil the geometric requirements of a bone tissue scaffold. The main objective of this work is to compare the mechanical properties of ceramic pieces of three different forms of TPMS printed in 3D using a commercial ceramic paste. In this way it will be possible to clarify which is the TPMS with appropriate characteristics to construct scaffolds of ceramic materials for bone repair. A dependence of the mechanical properties with the geometry was found being the Primitive Surface which shows the highest mechanical properties.

Effect of carbon black composition with sludge palm oil on the curing characteristic and mechanical properties of natural rubber/styrene butadiene rubber compound

Science.gov (United States)

Mohamed, R.; Nurazzi, N. Mohd; Huzaifah, M.

2017-07-01

This study was conducted to investigate the possibility of utilizing sludge palm oil (SPO) as processing oil, with various amount of carbon black as its reinforcing filler, and its effects on the curing characteristics and mechanical properties of natural rubber/styrene butadiene rubber (NR/SBR) compound. Rubber compound with fixed 15 pphr of SPO loading, and different carbon black loading from 20 to 50 pphr, was prepared using two roll mills. The cure characteristics and mechanical tests that have been conducted are the scorch and cure time analysis, tensile strength and tear strength. Scorch time (ts5) and cure time (t90) of the compound increases with the increasing carbon black loading. The mechanical properties of NR/SBR compound viz. the tensile strength, modulus at 300% strain and tear strength were also improved by the increasing carbon black loading.

Effect of tumbling time, injection rate and k-carrageenan addition on processing, textural and color characteristics of pork Biceps femoris muscle

Directory of Open Access Journals (Sweden)

Livia PATRAŞCU

2013-08-01

Full Text Available The effect of tumbling time (0-9 hours, injection rate (20-50% and k carrageenan addition (0.25 - 0.5% on quality characteristics of cooked pork Biceps femoris muscle have been studied. Properties of injected and tumbled meat samples were determined by measuring processing characteristics (tumbling yield, cooking yield and expressible moisture, color (L*, a*, b*, Hue angle and Chroma and texture (firmness, toughness, adhesiveness, work of adhesion and fracturability. Increasing tumbling time up to 9 h led to better hydration properties and increased the cooking yield for all samples, both with 0.25% and 0.5% of k-carrageenan addition. It also decreased the firmness and toughness of the evaluated samples. Biceps femoris samples containing a higher level of k-carrageenan were tenderer than those containing less polysaccharide. Neither injection rate nor tumbling time affected the color components of the analyzed samples.

Structure-property-processing correlations in freeze-cast composite scaffolds.

Science.gov (United States)

Hunger, Philipp M; Donius, Amalie E; Wegst, Ulrike G K

2013-05-01

Surprisingly few reports have been published, to date, on the structure-property-processing correlations observed in freeze-cast materials directionally solidified from polymer solutions, or ceramic or metal slurries. The studies that exist focus on properties of sintered ceramics, that is materials whose structure was altered by further processing. In this contribution, we report first results on correlations observed in alumina-chitosan-gelatin composites, which were chosen as a model system to test and compare the effect of particle size and processing parameters on their mechanical properties at a specific composition. Our study reveals that highly porous (>90%) hybrid materials can be manufactured by freeze casting, through the self-assembly of a polymer and a ceramic phase that occurs during directional solidification, without the need of additional processing steps such as sintering or infiltration. It further illustrates that the properties of freeze-cast hybrid materials can independently be tailored at two levels of their structural hierarchy, allowing for the simultaneous optimization of both mechanical and structural requirements. An increase in freezing rate resulted in decreases in lamellar spacing, cell wall thickness, pore aspect ratio and cross-sectional area, as well as increases in both Young's modulus and compressive yield strength. The mechanical properties of the composite scaffolds increased with an increasing particle size. The results show that both structure and mechanical properties of the freeze-cast composites can be custom-designed and that they are thus ideally suited for a large variety of applications that require high porosity at low or medium load-bearing capacity. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Effect of Electron Beam Irradiation of the Characteristics of Jute Fibers and the Interfacial Properties of Jute/PLA Green Composites

Energy Technology Data Exchange (ETDEWEB)

Ji, Sang Gyu; Cho, Dong Hwan [Kumoh National Institute of Technology, Gumi (Korea, Republic of); Lee, Byung Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2010-07-01

Cellulose-based natural fibers such as jute, knife and hemp have promising potential as a replacement for glass fibers in a polymer composite system because of their many advantages like natural abundance, low cost, light weight, biodegradability, carbon dioxide reduction in nature and acceptable mechanical properties. However, natural fibers need an appropriate surface treatment modifying their surface characteristics in order to effectively improve the interfacial properties as well as the mechanical and thermal properties. Electron beam irradiation technique is particularly interesting as it may offer the possibility to modify the surfaces and to enhance the properties of polymer materials such as fibers, films and composites. In addition, electron beam processing has a merit because it is a dry, solvent free and eco-friendly method with a fast throughput rate. In the present study, Jute fibers were irradiated at different dosages of electron beam from 10 to 100 kGy. The result was compared with raw jute fibers un-irradiated, showing the effect on the interfacial shear strength between jute fibers and PLA in terms of single fiber tensile property, fiber surface topology, and chemical composition occurring in jute fibers upon irradiation. It has been found that the surface topology and chemical characteristics of jute fibers significantly depended on the electron beam dosage irradiated, directly influencing the interfacial shear strength and interlaminar shear strength of jute-PLA green composites. It was concluded that electron beam irradiation played a contributing role not only in physically modifying the jute fiber surfaces but also in improving the interfacial properties between jute fibers and poly in the green composite, exhibiting the most effectiveness at a low electron beam energy of 10 kGy.

Effects of ultrasound pretreatment on the characteristic evolutions of drinking water treatment sludge and its impact on coagulation property of sludge recycling process.

Science.gov (United States)

Zhou, Zhiwei; Yang, Yanling; Li, Xing

2015-11-01

Large amounts of drinking water treatment sludge (DWTS) are produced during the flocculation or flotation process. The recycling of DWTS is important for reducing and reclaiming the waste residues from drinking water treatment. To improve the coagulation step of the DWTS recycling process, power ultrasound was used as a pretreatment to disintegrate the DWTS and degrade or inactivate the constituents that are difficult to remove by coagulation. The effects of ultrasound pretreatment on the characteristics of DWTS, including the extent of disintegration, variation in DWTS floc characteristics, and DWTS dewaterability, were investigated. The capacity of the recycling process to remove particulates and organic matter from low-turbidity surface water compared to a control treatment process without DWTS was subsequently evaluated. The coagulation mechanism was further investigated by analyzing the formation, breakage, and re-growth of re-coagulated flocs. Our results indicated that under the low energy density applied (0.03-0.033 W/mL) for less than 15 min at a frequency of 160 kHz, the level of organic solubilization was less elevated, which was evidenced by the lower release of proteins and polysaccharides and lower fluorescence intensities of humic- and protein-like substances. The applied ultrasound conditions had an adverse effect on the dewaterability of the DWTS. Ultrasound pretreatment had no significant impact on the pH or surface charge of the DWTS flocs, whereas particle size decreased slightly and the specific surface area was moderately increased. The pollution removal capacity decreased somewhat for the recycled sonicated DWTS treatment, which was primarily ascribed to organic solubilization rather than variability in the floc characteristics of sonicated DWTS. The main coagulation mechanism was floc sweeping and physical adsorption. The breakage process of the flocs formed by the recycling process displayed distinct irreversibility, and the flocs were

Effect of Energy Input on the Characteristic of AISI H13 and D2 Tool Steels Deposited by a Directed Energy Deposition Process

Science.gov (United States)

Park, Jun Seok; Park, Joo Hyun; Lee, Min-Gyu; Sung, Ji Hyun; Cha, Kyoung Je; Kim, Da Hye

2016-05-01

Among the many additive manufacturing technologies, the directed energy deposition (DED) process has attracted significant attention because of the application of metal products. Metal deposited by the DED process has different properties than wrought metal because of the rapid solidification rate, the high thermal gradient between the deposited metal and substrate, etc. Additionally, many operating parameters, such as laser power, beam diameter, traverse speed, and powder mass flow rate, must be considered since the characteristics of the deposited metal are affected by the operating parameters. In the present study, the effect of energy input on the characteristics of H13 and D2 steels deposited by a direct metal tooling process based on the DED process was investigated. In particular, we report that the hardness of the deposited H13 and D2 steels decreased with increasing energy input, which we discuss by considering microstructural observations and thermodynamics.

KNOWLEDGE MANAGEMENT PROCESSES AND INTELLECTUAL PROPERTY MANAGEMENT PROCESSES: AN INTEGRATED CONCEPTUAL FRAMEWORK

OpenAIRE

HENAO-CALAD, MONICA; RIVERA-MONTOYA, PAULA; URIBE-OCHOA, BEATRIZ

2017-01-01

ABSTRACT Intellectual property management, knowledge management are disciplines that have been treated independently, both in academia and in the organizational field. Through the legal discipline of intellectual property, the former manages intangible assets that are eligible for protection (copyright, patents and trademarks, among others) leaving aside those assets that cannot be realized in any way. The latter is devoted to the processes of knowledge management in general, namely, the know...

Property optimization of nanostructured ARB-processed Al by post-process deformation

DEFF Research Database (Denmark)

Huang, Xiaoxu; Kamikawa, Naoya; Hansen, Niels

2008-01-01

The effect of post-process deformation on the mechanical properties of nanostructured aluminum (99.2% purity) has been investigated by cold rolling of samples which have been processed by accumulative roll bonding (ARB) to a strain of epsilon(vM) = 4.8. Samples have been cold rolled to 10, 15...... material. In contrary, cold rolling to large strain (50%) results in significant strengthening. This leads to the suggestion of a transition strain within the range of 25-35% reduction by rolling. The microstructural evolution during post-process deformation has been followed by transmission electron...

Some properties of point processes in statistical optics

International Nuclear Information System (INIS)

Picinbono, B.; Bendjaballah, C.

2010-01-01

The analysis of the statistical properties of the point process (PP) of photon detection times can be used to determine whether or not an optical field is classical, in the sense that its statistical description does not require the methods of quantum optics. This determination is, however, more difficult than ordinarily admitted and the first aim of this paper is to illustrate this point by using some results of the PP theory. For example, it is well known that the analysis of the photodetection of classical fields exhibits the so-called bunching effect. But this property alone cannot be used to decide the nature of a given optical field. Indeed, we have presented examples of point processes for which a bunching effect appears and yet they cannot be obtained from a classical field. These examples are illustrated by computer simulations. Similarly, it is often admitted that for fields with very low light intensity the bunching or antibunching can be described by using the statistical properties of the distance between successive events of the point process, which simplifies the experimental procedure. We have shown that, while this property is valid for classical PPs, it has no reason to be true for nonclassical PPs, and we have presented some examples of this situation also illustrated by computer simulations.

Influência das características estruturais sobre a processabilidade do polibutadieno alto cis Influence of structural characteristics on the high-cis polybutadiene processability

Directory of Open Access Journals (Sweden)

Ivana L. Mello

2004-01-01

Full Text Available Características físicas, tais como peso molecular, distribuição de peso molecular e ramificações, têm importância significativa na processabilidade do polibutadieno. Assim, deve haver um balanceamento dessas características a fim de se obter boas propriedades mecânicas e boa processabilidade. Este Trabalho apresenta uma breve revisão sobre a influência das características estruturais na processabilidade do polibutadieno produzido por diferentes sistemas catalíticos. São apresentadas também algumas técnicas encontradas na literatura para melhorar a processabilidade desse elastômero.Physical characteristics, such as, molecular weight, molecular weight distribution and branching, have a significant influence on polybutadiene processability. Thus, a balance should exist in these characteristics for good mechanical properties and processability. This work brings a brief review of the influence of structural characteristics on the processability of polybutadiene produced by different catalyst systems. Also presented are some techniques from the literature aimed at improving processability of this elastomer.

Processing, structure, property and performance relationships for the thermal spray of the internal surface of aluminum cylinders

Science.gov (United States)

Cook, David James

The increased need for automotive weight reduction has necessitated the use of aluminum for engine blocks. Conventional aluminum alloys cannot survive the constant wear from a piston ring reciprocating on the surface. However, a wear resistant thermal spray coating can be applied on the internal surface of the cylinder bore, which has significant advantages over other available options. Thermal spray is a well-established process for depositing molten, semi-molten, or solid particles onto a substrate to form a protective coating. For this application, the two main challenges were obtaining good wear resistance, and achieving good adhesion. To design a system capable of producing a well-adhered, wear resistant coating for this high volume application it is necessary to identify the overall processing, structure, properties, and performance relationships. The results will demonstrate that very important relationships exist among particle characteristics, substrate conditions, and the properties of the final coating. However, it is the scientific studies to understand some of the process physics in these relationships that allow recognition of the critical processing conditions that need to be controlled to ensure a consistent, reliable thermal spray coating. In this investigation, it will be shown that the critical microstructural aspect of the coating that produced the required tribological properties was the presence of wuestite (FeO). It was found that by using a low carbon steel material with compressed air atomizing gas, it was possible to create an Fe/FeO structure that exhibited excellent tribological properties. This study will also show that traditional thermal spray surface preparation techniques were not ideal for this application, therefore a novel alternative approach was developed. The application of a flux to the aluminum surface prior to thermal spray promotes excellent bond strengths to non-roughened aluminum. Analysis will show that this flux strips

Characteristics of diffusion zone in changing glass-metal composite processing conditions

Science.gov (United States)

Lyubimova, O. N.; Morkovin, A. V.; Andreev, V. V.

2018-03-01

The influence of manufacturing technology on the characteristics of the glass and steel contact zone in manufacturing new structural material - glass-metal composite is studied theoretically and experimentally. Different types of structures in the contact zone and its dimensions affect the strength characteristics of the composite. Knowledge about changing the width of the glass and steel contact zone after changing such parameters of the technological regime as temperature, holding time and use of solders will allow one to control the structure and characteristics of the glass-metal composite. Experimental measurements of the width of the diffusion zone in the glass-metal composite for different regimes and their statistical processing according to the full factor experiment are presented in this article. The results of analysis of some mechanical characteristics of the diffusion zone are presented: microhardness and modulus of elasticity for samples, prepared according to different processing regimes.

The characteristics of purpose built offices in Malaysia: a review of issues

OpenAIRE

Mohd Safian, Edie Ezwan; Bagdad, Mariati; Nawawi, Abdul Hadi

2011-01-01

The development of purpose-built office market in Malaysia is basically determined by a supply-demand market. Since the purpose built office market in Malaysia has shown positive developments and increasing level of competitiveness, many building and locational characteristics have emerged and become important during the process of assessment of the office property involving property market appraisal and building performance evaluation. With these characteristics, property market participants...

Biochar characteristics produced from food-processing products and their sorptive capacity for mercury and phenanthrene

Science.gov (United States)

Fotopoulou, Kalliopi N.; Karapanagioti, Hrissi K.; Manariotis, Ioannis D.

2015-04-01

Various organic-rich wastes including wood chips, animal manure, and crop residues have been used for biochar production. Biochar is used as an additive to soils to sequester carbon and improve soil fertility but its use as a sorbent for environmental remediation processes is gaining increased attention. Surface properties such as point of zero charge, surface area and pore volume, surface topography, surface functional groups and acid-base behavior are important factors, which affect sorption efficiency. Understanding the surface alteration of biochars increases our understanding of the pollutant-sorbent interaction. The scope of the present work was to evaluate the effect of key characteristics of biochars on their sorptive properties. Raw materials for biochar production were evaluated including byproducts from brewering, coffee, wine, and olive oil industry. The charring process was performed at different temperatures under limited-oxygen conditions using specialized containers. The surface area, the pore volume, and the average pore size of the biochars were determined. Open surface area and micropore volume were determined using t-plot method and Harkins & Jura equation. Raw food-processing waste demonstrates low surface area that increases by 1 order of magnitude by thermal treatment up to 750oC. At temperatures from 750 up to 900oC, pyrolysis results to biochars with surface areas 210-700 m2/g. For the same temperature range, a high percentage (46 to73%) of the pore volume of the biochars is due to micropores. Positive results were obtained when high surface area biochars were tested for their ability to remove organic (i.e. phenanthrene) and inorganic (i.e. mercury) compounds from aqueous solutions. All these properties point to new materials that can effectively be used for environmental remediation.

Process Formulations And Curing Conditions That Affect Saltstone Properties

Energy Technology Data Exchange (ETDEWEB)

Reigel, M. M.; Pickenheim, B. R.; Daniel, W. E.

2012-09-28

The first objective of this study was to analyze saltstone fresh properties to determine the feasibility of reducing the formulation water to premix (w/p) ratio while varying the amount of extra water and admixtures used during processing at the Saltstone Production Facility (SPF). The second part of this study was to provide information for understanding the impact of curing conditions (cure temperature, relative humidity (RH)) and processing formulation on the performance properties of cured saltstone.

The influence of oxidation properties on the electron emission characteristics of porous silicon

International Nuclear Information System (INIS)

He, Li; Zhang, Xiaoning; Wang, Wenjiang; Wei, Haicheng

2016-01-01

Highlights: • Evaluated the oxidation properties of porous silicon from semi-quantitative methods. • Discovered the relationship between oxidation properties and emission characteristics. • Revealed the micro-essence of the electron emission of the porous silicon. - Abstract: In order to investigate the influence of oxidation properties such as oxygen content and its distribution gradient on the electron emission characteristics of porous silicon (PS) emitters, emitters with PS thickness of 8 μm, 5 μm, and 3 μm were prepared and then oxidized by electrochemical oxidation (ECO) and ECO-RTO (rapid thermal oxidation) to get different oxidation properties. The experimental results indicated that the emission current density, efficiency, and stability of the PS emitters are mainly determined by oxidation properties. The higher oxygen content and the smaller oxygen distribution gradient in the PS layer, the larger emission current density and efficiency we noted. The most favorable results occurred for the PS emitter with the smallest oxygen distribution gradient and the highest level of oxygen content, with an emission current density of 212.25 μA/cm"2 and efficiency of 59.21‰. Additionally, it also demonstrates that thick PS layer benefits to the emission stability due to its longer electron acceleration tunnel. The FN fitting plots indicated that the effective emission areas of PS emitters can be enlarged and electron emission thresholds is decreased because of the higher oxygen content and smaller distribution gradient, which were approved by the optical micrographs of top electrode of PS emitters before and after electron emission.

The influence of oxidation properties on the electron emission characteristics of porous silicon

Energy Technology Data Exchange (ETDEWEB)

He, Li [Key Laboratory of Physical Electronics and Devices of the Ministry of Education, Xi’an Jiaotong University, Xi’an 710049 (China); Zhang, Xiaoning, E-mail: znn@mail.xjtu.edu.cn [Key Laboratory of Physical Electronics and Devices of the Ministry of Education, Xi’an Jiaotong University, Xi’an 710049 (China); Wang, Wenjiang [Key Laboratory of Physical Electronics and Devices of the Ministry of Education, Xi’an Jiaotong University, Xi’an 710049 (China); Wei, Haicheng [School of Electrical and Information Engineering, Beifang University of Nationalities, Yinchuan750021 (China)

2016-09-30

Highlights: • Evaluated the oxidation properties of porous silicon from semi-quantitative methods. • Discovered the relationship between oxidation properties and emission characteristics. • Revealed the micro-essence of the electron emission of the porous silicon. - Abstract: In order to investigate the influence of oxidation properties such as oxygen content and its distribution gradient on the electron emission characteristics of porous silicon (PS) emitters, emitters with PS thickness of 8 μm, 5 μm, and 3 μm were prepared and then oxidized by electrochemical oxidation (ECO) and ECO-RTO (rapid thermal oxidation) to get different oxidation properties. The experimental results indicated that the emission current density, efficiency, and stability of the PS emitters are mainly determined by oxidation properties. The higher oxygen content and the smaller oxygen distribution gradient in the PS layer, the larger emission current density and efficiency we noted. The most favorable results occurred for the PS emitter with the smallest oxygen distribution gradient and the highest level of oxygen content, with an emission current density of 212.25 μA/cm{sup 2} and efficiency of 59.21‰. Additionally, it also demonstrates that thick PS layer benefits to the emission stability due to its longer electron acceleration tunnel. The FN fitting plots indicated that the effective emission areas of PS emitters can be enlarged and electron emission thresholds is decreased because of the higher oxygen content and smaller distribution gradient, which were approved by the optical micrographs of top electrode of PS emitters before and after electron emission.

Modeling process-structure-property relationships for additive manufacturing

Science.gov (United States)

Yan, Wentao; Lin, Stephen; Kafka, Orion L.; Yu, Cheng; Liu, Zeliang; Lian, Yanping; Wolff, Sarah; Cao, Jian; Wagner, Gregory J.; Liu, Wing Kam

2018-02-01

This paper presents our latest work on comprehensive modeling of process-structure-property relationships for additive manufacturing (AM) materials, including using data-mining techniques to close the cycle of design-predict-optimize. To illustrate the processstructure relationship, the multi-scale multi-physics process modeling starts from the micro-scale to establish a mechanistic heat source model, to the meso-scale models of individual powder particle evolution, and finally to the macro-scale model to simulate the fabrication process of a complex product. To link structure and properties, a highefficiency mechanistic model, self-consistent clustering analyses, is developed to capture a variety of material response. The model incorporates factors such as voids, phase composition, inclusions, and grain structures, which are the differentiating features of AM metals. Furthermore, we propose data-mining as an effective solution for novel rapid design and optimization, which is motivated by the numerous influencing factors in the AM process. We believe this paper will provide a roadmap to advance AM fundamental understanding and guide the monitoring and advanced diagnostics of AM processing.

Some properties of the fractional Ornstein-Uhlenbeck process

International Nuclear Information System (INIS)

Yan Litan; Lu Yunsheng; Xu Zhiqiang

2008-01-01

We consider the fractional analogue of the Ornstein-Uhlenbeck process, i.e. the solution of the Langevin equation driven by a fractional Brownian motion in place of the usual Brownian motion. We establish some properties of these processes. We show that the process is local nondeterminism. For a two-dimensional process we show that its renormalized self-intersection local time exists in L 2 if and only if 0< H<3/4

Effect of Uncertainties in Physical Property Estimates on Process Design - Sensitivity Analysis

DEFF Research Database (Denmark)

Hukkerikar, Amol; Jones, Mark Nicholas; Sin, Gürkan

for performing sensitivity of process design subject to uncertainties in the property estimates. To this end, first uncertainty analysis of the property models of pure components and their mixtures was performed in order to obtain the uncertainties in the estimated property values. As a next step, sensitivity......Chemical process design calculations require accurate and reliable physical and thermodynamic property data and property models of pure components and their mixtures in order to obtain reliable design parameters which help to achieve desired specifications. The uncertainties in the property values...... can arise from the experiments itself or from the property models employed. It is important to consider the effect of these uncertainties on the process design in order to assess the quality and reliability of the final design. The main objective of this work is to develop a systematic methodology...

Process depending morphology and resulting physical properties of TPU

Energy Technology Data Exchange (ETDEWEB)

Frick, Achim, E-mail: achim.frick@hs-aalen.de; Spadaro, Marcel, E-mail: marcel.spadaro@hs-aalen.de [Institute of Polymer Science and Processing (iPSP), Aalen University (Germany)

2015-12-17

Thermoplastic polyurethane (TPU) is a rubber like material with outstanding properties, e.g. for seal applications. TPU basically provides high strength, low frictional behavior and excellent wear resistance. Though, due to segmented structure of TPU, which is composed of hard segments (HSs) and soft segments (SSs), physical properties depend strongly on the morphological arrangement of the phase separated HSs at a certain ratio of HSs to SSs. It is obvious that the TPU deforms differently depending on its bulk morphology. Basically, the morphology can either consist of HSs segregated into small domains, which are well dispersed in the SS matrix or of few strongly phase separated large size HS domains embedded in the SS matrix. The morphology development is hardly ruled by the melt processing conditions of the TPU. Depending on the morphology, TPU provides quite different physical properties with respect to strength, deformation behavior, thermal stability, creep resistance and tribological performance. The paper deals with the influence of important melt processing parameters, such as temperature, pressure and shear conditions, on the resulting physical properties tested by tensile and relaxation experiments. Furthermore the morphology is studied employing differential scanning calorimeter (DSC), transmission light microscopy (TLM), scanning electron beam microscopy (SEM) and transmission electron beam microscopy (TEM) investigations. Correlations between processing conditions and resulting TPU material properties are elaborated. Flow and shear simulations contribute to the understanding of thermal and flow induced morphology development.

Phenolic Composition and Related Properties of Aged Wine Spirits: Influence of Barrel Characteristics. A Review

Directory of Open Access Journals (Sweden)

Sara Canas

2017-11-01

Full Text Available The freshly distilled wine spirit has a high concentration of ethanol and many volatile compounds, but is devoid of phenolic compounds other than volatile phenols. Therefore, an ageing period in the wooden barrel is required to attain sensory fullness and high quality. During this process, several phenomena take place, namely the release of low molecular weight phenolic compounds and tannins from the wood into the wine spirit. Research conducted over the last decades shows that they play a decisive role on the physicochemical characteristics and relevant sensory properties of the beverage. Their contribution to the antioxidant activity has also been emphasized. Besides, some studies show the modulating effect of the ageing technology, involving different factors such as the barrel features (including the wood botanical species, those imparted by the cooperage technology, and the barrel size, the cellar conditions, and the operations performed, on the phenolic composition and related properties of the aged wine spirit. This review aims to summarize the main findings on this topic, taking into account two featured barrel characteristics—the botanical species of the wood and the toasting level.

Emission characteristics of nitrogen- and sulfur-containing odorous compounds during different sewage sludge chemical conditioning processes

Energy Technology Data Exchange (ETDEWEB)

Liu, Huan [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Luo, Guang-Qian; Hu, Hong-Yun [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China); Zhang, Qiang; Yang, Jia-Kuan [School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Yao, Hong, E-mail: hyao@hust.edu.cn [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China)

2012-10-15

Highlights: Black-Right-Pointing-Pointer NH{sub 3}, SO{sub 2}, H{sub 2}S and COS are emitted during different sludge conditioning processes. Black-Right-Pointing-Pointer H{sub 2}S and SO{sub 2} generation increase in the acidic environment created by H{sub 2}SO{sub 4}. Black-Right-Pointing-Pointer Fenton peroxidation facilitates the formation of COS. Black-Right-Pointing-Pointer CaO can reduce sulfur-containing gases emission via generation of calcium sulfate. Black-Right-Pointing-Pointer CaO leads to the conversion of free ammonia or protonated amine to volatile NH{sub 3}. - Abstract: Chemical conditioners are often used to enhance sewage sludge dewaterability through altering sludge properties and flocs structure, both affect odorous compounds emissions not only during sludge conditioning but also in subsequent sludge disposal. This study was to investigate emission characteristics of ammonia (NH{sub 3}), sulfur dioxide (SO{sub 2}), hydrogen sulfide (H{sub 2}S) and carbonyl sulfide (COS) generated from sewage sludge conditioned by three representative conditioners, i.e., organic polymers, iron salts and skeleton builders, F-S (Fenton's reagent and skeleton builders) composite conditioner. The results demonstrate that polyacrylamide (PAM) has an insignificant effect on emission characteristics of nitrogen- and sulfur-containing odorous compounds, because the properties, sulfur and nitrogen speciations are similar in PAM-conditioned sludge and raw sludge (RS). Significant increases of SO{sub 2} and H{sub 2}S emissions in the H{sub 2}SO{sub 4} conditioning process were observed due to the accelerated decomposition of sulfur-containing amino acids in acidic environment. Fenton peroxidation facilitates the formation of COS. CaO can reduce sulfur-containing gases emission via generation of calcium sulfate. However, under strong alkaline conditions, free ammonia or protonated amine in sludge can be easily converted to volatile ammonia, resulting in a significant

Processing and properties of carbon nanofibers reinforced epoxy powder composites

International Nuclear Information System (INIS)

Palencia, C.; Mazo, M. A.; Nistal, A.; Rubio, F.; Rubio, J.; Oteo, J. L.

2011-01-01

Commercially available CNFs (diameter 30–300 nm) have been used to develop both bulk and coating epoxy nanocomposites by using a solvent-free epoxy matrix powder. Processing of both types of materials has been carried out by a double-step process consisting in an initial physical premix of all components followed by three consecutive extrusions. The extruded pellets were grinded into powder and sieved. Carbon nanofibers powder coatings were obtained by electrostatic painting of the extruded powder followed by a curing process based in a thermal treatment at 200 °C for 25 min. On the other hand, for obtaining bulk carbon nanofibers epoxy composites, a thermal curing process involving several steps was needed. Gloss and mechanical properties of both nanocomposite coatings and bulk nanocomposites were improved as a result of the processing process. FE-SEM fracture surface microphotographs corroborate these results. It has been assessed the key role played by the dispersion of CNFs in the matrix, and the highly important step that is the processing and curing of the nanocomposites. A processing stage consisted in three consecutive extrusions has reached to nanocomposites free of entanglements neither agglomerates. This process leads to nanocomposite coatings of enhanced properties, as it has been evidenced through gloss and mechanical properties. A dispersion limit of 1% has been determined for the studied system in which a given dispersion has been achieved, as the bending mechanical properties have been increased around 25% compared with the pristine epoxy resin. It has been also demonstrated the importance of the thickness in the nanocomposite, as it involves the curing stage. The complex curing treatment carried out in the case of bulk nanocomposites has reached to reagglomeration of CNFs.

Processing and properties of carbon nanofibers reinforced epoxy powder composites

Science.gov (United States)

Palencia, C.; Mazo, M. A.; Nistal, A.; Rubio, F.; Rubio, J.; Oteo, J. L.

2011-11-01

Commercially available CNFs (diameter 30-300 nm) have been used to develop both bulk and coating epoxy nanocomposites by using a solvent-free epoxy matrix powder. Processing of both types of materials has been carried out by a double-step process consisting in an initial physical premix of all components followed by three consecutive extrusions. The extruded pellets were grinded into powder and sieved. Carbon nanofibers powder coatings were obtained by electrostatic painting of the extruded powder followed by a curing process based in a thermal treatment at 200 °C for 25 min. On the other hand, for obtaining bulk carbon nanofibers epoxy composites, a thermal curing process involving several steps was needed. Gloss and mechanical properties of both nanocomposite coatings and bulk nanocomposites were improved as a result of the processing process. FE-SEM fracture surface microphotographs corroborate these results. It has been assessed the key role played by the dispersion of CNFs in the matrix, and the highly important step that is the processing and curing of the nanocomposites. A processing stage consisted in three consecutive extrusions has reached to nanocomposites free of entanglements neither agglomerates. This process leads to nanocomposite coatings of enhanced properties, as it has been evidenced through gloss and mechanical properties. A dispersion limit of 1% has been determined for the studied system in which a given dispersion has been achieved, as the bending mechanical properties have been increased around 25% compared with the pristine epoxy resin. It has been also demonstrated the importance of the thickness in the nanocomposite, as it involves the curing stage. The complex curing treatment carried out in the case of bulk nanocomposites has reached to reagglomeration of CNFs.

New Evidences on the Process Sensitivity of Some Renewable Blends Based on Starch considering Their Melt Rheological Properties

Directory of Open Access Journals (Sweden)

Doina Dimonie

2016-01-01

Full Text Available The degradability and processability of new renewable materials based on starch and PVOH were studied using the melt flow index (MFI method by measuring the melt rheological properties which depend not only on the extrusion conditions and material formulation but also on the macromolecule characteristics which can be modified by chemical degradation. These results were correlated with other material properties like color and cross-linking degree. The obtained results show that flowing in the melted state of the studied materials is accompanied by a second process of chains chemical degradation. It was observed that, at the same level of additivation, under identical extrusion conditions, the melted blends with corn starch as main component are highly mechanically sensitive and degrade mostly by chains scission and those with PVOH as major component are highly temperature sensitive and degrade mainly by cross-linking. The obtained results show also that each PVOH-starch blend requires particular formulation and individual windows of melt processing conditions. These results are a good proof that the MFI method is a good path to study the degradability and moldability of process sensitive polymeric materials like those based on starch and PVOH.

Molecular markers of benzene polycarboxylic acids in describing biochar physiochemical properties and sorption characteristics.

Science.gov (United States)

Chang, Zhaofeng; Tian, Luping; Wu, Min; Dong, Xudong; Peng, Juan; Pan, Bo

2018-06-01

Biochar function in soil is based on properties such as sorption characteristics, and these are expected to change throughout the life cycle of the biochar. Because biochar particles cannot easily be separated from soil particles, this change is seldom investigated. Biochar-related molecular markers, such as benzene polycarboxylic acids (BPCAs) are promising tools for studying the properties of biochars in complex environmental matrices. In this study, biochars were derived from corn straw and pine wood sawdust at 200-500 °C, and their aging was simulated with NaClO. Biochar properties were characterized by elemental analysis, BET surface characterization and BPCA molecular marker analysis. Chemical oxidation decreased the surface area (SA) but increased the O content of biochars. The oxidation decreased the amount of biochars, with a mass loss in the range of 10-55%. A similar mass loss was also observed for BPCAs and was negatively related to both the pyrolysis temperature and the extent of the condensed structure (higher aromaticity). The biochar amounts were calculated quantitatively using the sum of BPCA contents, with a conversion factor (the ratio of biochar amount to BPCA content) in the range of 3.3-5.5, and were negatively related to the B5CA content. Three model pollutants, namely, bisphenol A (BPA), sulfamethoxazole (SMX), and phenanthrene (PHE), were chosen to study the sorption characteristics of biochar before and after oxidation. Chemical oxidation generally increased SMX sorption but decreased PHE sorption. The nonlinear factor n, based on Freundlich equation modeling, was negatively related to B6CA for all three chemicals. The BPCA molecular markers, especially B5CA and B6CA, were correlated to the biochar properties before and after oxidation and are thus a potentially useful technique for describing the characteristics of biochar in the environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Microphysical characteristics of squall-line stratiform precipitation and transition zones inferred using an ice particle property-evolving model

Science.gov (United States)

Jensen, A. A.; Harrington, J. Y.; Morrison, H.

2017-12-01

A quasi-idealized 3D squall line (based on a June 2007 Oklahoma case) is simulated using a novel bulk microphysics scheme called the Ice-Spheroids Habit Model with Aspect-ratio Evolution (ISHMAEL). In ISHMAEL, the evolution of ice particle properties, such as mass, shape, maximum diameter, density, and fall speed, are tracked as these properties evolve from vapor growth, sublimation, riming, and melting. Thus, ice properties evolve from various microphysical processes without needing separate unrimed and rimed ice categories. Simulation results show that ISHMAEL produces both a squall-line transition zone and an enhanced stratiform precipitation region. The ice particle properties produced in this simulation are analyzed and compared to observations to determine the characteristics of ice that lead to the development of these squall-line features. It is shown that rimed particles advected rearward from the convective region produce the enhanced stratiform precipitation region. The development of the transition zone results from hydrometer sorting: the evolution of ice particle properties in the convective region produces specific fall speeds that favor significant ice advecting rearward of the transition zone before reaching the melting level, causing a local minimum in precipitation rate and reflectivity there. Microphysical sensitivity studies, for example turning rime splintering off, that lead to changes in ice particle properties reveal that the fall speed of ice particles largely determines both the location of the enhanced stratiform precipitation region and whether or not a transition zone forms.

Relation between the plasma characteristics and physical properties of functional zinc oxide thin film prepared by radio frequency magnetron sputtering process

International Nuclear Information System (INIS)

Hsu, Che-Wei; Cheng, Tsung-Chieh; Huang, Wen-Hsien; Wu, Jong-Shinn; Cheng, Cheng-Chih; Cheng, Kai-Wen; Huang, Shih-Chiang

2010-01-01

The ZnO thin film was deposited on a glass substrate by a RF reactive magnetron sputtering method. Results showed that plasma density, electron temperature, deposition rate and estimated ion bombardment energy increase with increasing applied RF power. Three distinct power regimes were observed, which are strongly correlated with plasma properties. In the low-power regime, the largest grain size was observed due to slow deposition rate. In the medium-power regime, the smallest grain size was found, which is attributed to insufficient time for the adatoms to migrate on substrate surface. In the high-power regime, relatively larger grain size was found due to very large ion bombardment energy which enhances the thermal migration of adatoms. Regardless of pure ZnO thin film or ZnO on glass, high transmittance (> 80%) in the visible region can be generally observed. However, the film thickness plays a more important role for controlling optical properties, especially in the UV region, than the applied RF power. In general, with properly coated ZnO thin film, we can obtain a glass substrate which is highly transparent in the visible region, is of good anti-UV characteristics, and is highly hydrophobic, which is highly suitable for applications in the glass industry.

Hidden symmetries and equilibrium properties of multiplicative white-noise stochastic processes

International Nuclear Information System (INIS)

Arenas, Zochil González; Barci, Daniel G

2012-01-01

Multiplicative white-noise stochastic processes continue to attract attention in a wide area of scientific research. The variety of prescriptions available for defining them makes the development of general tools for their characterization difficult. In this work, we study equilibrium properties of Markovian multiplicative white-noise processes. For this, we define the time reversal transformation for such processes, taking into account that the asymptotic stationary probability distribution depends on the prescription. Representing the stochastic process in a functional Grassmann formalism, we avoid the necessity of fixing a particular prescription. In this framework, we analyze equilibrium properties and study hidden symmetries of the process. We show that, using a careful definition of the equilibrium distribution and taking into account the appropriate time reversal transformation, usual equilibrium properties are satisfied for any prescription. Finally, we present a detailed deduction of a covariant supersymmetric formulation of a multiplicative Markovian white-noise process and study some of the constraints that it imposes on correlation functions using Ward–Takahashi identities. (paper)

Hidden symmetries and equilibrium properties of multiplicative white-noise stochastic processes

Science.gov (United States)

González Arenas, Zochil; Barci, Daniel G.

2012-12-01

Multiplicative white-noise stochastic processes continue to attract attention in a wide area of scientific research. The variety of prescriptions available for defining them makes the development of general tools for their characterization difficult. In this work, we study equilibrium properties of Markovian multiplicative white-noise processes. For this, we define the time reversal transformation for such processes, taking into account that the asymptotic stationary probability distribution depends on the prescription. Representing the stochastic process in a functional Grassmann formalism, we avoid the necessity of fixing a particular prescription. In this framework, we analyze equilibrium properties and study hidden symmetries of the process. We show that, using a careful definition of the equilibrium distribution and taking into account the appropriate time reversal transformation, usual equilibrium properties are satisfied for any prescription. Finally, we present a detailed deduction of a covariant supersymmetric formulation of a multiplicative Markovian white-noise process and study some of the constraints that it imposes on correlation functions using Ward-Takahashi identities.

Effect of La and W dopants on dielectric and ferroelectric properties of PZT thin films prepared by sol-gel process

International Nuclear Information System (INIS)

Xiao, Mi; Zhang, Zebin; Zhang, Weikang; Zhang, Ping

2018-01-01

La or W-doped lead zirconate titanate thin films (PLZT or PZTW) were prepared on platinized silicon substrates by sol-gel process. The effects of La or W dopant on the phase development, microstructure, dielectric and ferroelectric characteristics of films were studied. For PLZT films, the optimum doping concentration was found to be 2 mol%. While for PZTW films, the dielectric and ferroelectric properties were found to be improved as the doping concentration increased. The fatigue properties of PLZT and PZTW thin films were also investigated, the results showed that A- or B-site donor doping could improve the fatigue properties of PZT thin films. The theory of oxygen vacancy was used to explain the performance improvement caused by donor doping. (orig.)

Effect of La and W dopants on dielectric and ferroelectric properties of PZT thin films prepared by sol-gel process

Science.gov (United States)

Xiao, Mi; Zhang, Zebin; Zhang, Weikang; Zhang, Ping

2018-01-01

La or W-doped lead zirconate titanate thin films (PLZT or PZTW) were prepared on platinized silicon substrates by sol-gel process. The effects of La or W dopant on the phase development, microstructure, dielectric and ferroelectric characteristics of films were studied. For PLZT films, the optimum doping concentration was found to be 2 mol%. While for PZTW films, the dielectric and ferroelectric properties were found to be improved as the doping concentration increased. The fatigue properties of PLZT and PZTW thin films were also investigated, the results showed that A- or B-site donor doping could improve the fatigue properties of PZT thin films. The theory of oxygen vacancy was used to explain the performance improvement caused by donor doping.

The process and organizational characteristics of memory clinics in Israel in 2007.

Science.gov (United States)

Werner, Perla; Goldstein, Dovrat; Heinik, Jeremia

2009-01-01

We previously described the characteristics and activities of 25 memory clinics in Israel in 1998 using a mail survey. Questionnaires assessing the administrative structure of the clinics, patient characteristics, processes and methods used, and outcomes of the assessment were mailed again in 2007 to 35 memory clinics. Overall, the general operating characteristics of the clinics in 2007 were found to be similar to those reported in the previous survey conducted in 1998. The assessment process in 2007 was shorter than in 1998 (mean time=1.92 and 3.12 h, respectively), although both surveys were based on an interdisciplinary team, including a physician, a nurse and a social worker. However, in 2007 the teams were more wide-ranging. A wider variety of instruments were reported in the more recent survey. Most of the clinics in both surveys reported that family members were involved at all stages of the assessment. Medication treatment was the main outcome reported by the clinics in both surveys. There has been a development in the process and organizational characteristics of memory clinics in Israel over the years, probably as a consequence of the development of knowledge in the area of cognitive deterioration.

Characteristics of spectators in 4He nuclei fragmentation processes

International Nuclear Information System (INIS)

Bano, M.; Braun, H.; Futo, A.

1984-10-01

Characteristics were studieO of deuteron, 3 H and 3 He spectators emitted in 4 He-p interactions at 8.6 GeV/c incident momentum. A model using the Monte Carlo procedure is proposed which predicts the momentum distribution for a nucleon or a group of nucleons (d, 3 H, 3 He) in the 4 He nucleus and describes some properties of reaction channels with spectator emission. The predictions are compared with experimental data. Good agreement is obtained taking into account the influence of the experimental errors and of the binding energy between the fragments. (author)

Characteristics of the tensile mechanical properties of fresh and dry forewings of beetles

Energy Technology Data Exchange (ETDEWEB)

Tuo, Wanyong [School of Civil Engineering & International Institute for Urban Systems Engineering, Southeast University, Nanjing 210096 (China); School of Civil & Architectural Engineering, Anyang Institute of Technology, Anyang 455000 (China); Chen, Jinxiang, E-mail: chenjpaper@yahoo.co.jp [School of Civil Engineering & International Institute for Urban Systems Engineering, Southeast University, Nanjing 210096 (China); Wu, Zhishen; Xie, Juan [School of Civil Engineering & International Institute for Urban Systems Engineering, Southeast University, Nanjing 210096 (China); Wang, Yong [Nantong Vocational University, Nantong, Jiangsu 226007 (China)

2016-08-01

Based on a tensile experiment and observations by scanning electron microscopy (SEM), this study demonstrated the characteristics of the tensile mechanical properties of the fresh and dry forewings of two types of beetles. The results revealed obvious differences in the tensile fracture morphologies and characteristics of the tensile mechanical properties of fresh and dry forewings of Cybister tripunctatus Olivier and Allomyrina dichotoma. For fresh forewings of these two types of beetles, a viscous, flow-like, polymer matrix plastic deformation was observed on the fracture surfaces, with soft morphologies and many fibers being pulled out, whereas on the dry forewings, the tensile fracture surfaces were straightforward, and there were no features resembling those found on the fresh forewings. The fresh forewings exhibited a greater fracture strain than the dry forewings, which was caused by the relative slippage of hydroxyl inter-chain bonds due to the presence of water in the fibers and proteins in the fresh forewings. Our study is the first to demonstrate the phenomenon of sudden stress drops caused by the fracturing of the lower skin because the lower skin fractured before the forewings of A. dichotoma reached their ultimate tensile strength. We also investigated the reasons underlying this phenomenon. This research provides a much better understanding of the mechanical properties of beetle forewings and facilitates the correct selection of study objects for biomimetic materials and development of the corresponding applications. - Highlights: • There is a phenomenon of sudden stress drop on the tensile stress-train curve of forewing. • The causes of the differences of mechanical properties of fresh and dry forewings are explained. • The hypothesis raised in a previous review paper is verified. • This study brings better ideas into correct understanding of the mechanical properties that the biomimetic object exhibits.

Basic Instinct Undressed: Early Spatiotemporal Processing for Primary Sexual Characteristics

Science.gov (United States)

Legrand, Lore B.; Del Zotto, Marzia; Tyrand, Rémi; Pegna, Alan J.

2013-01-01

This study investigates the spatiotemporal dynamics associated with conscious and non-conscious processing of naked and dressed human bodies. To this effect, stimuli of naked men and women with visible primary sexual characteristics, as well as dressed bodies, were presented to 20 heterosexual male and female participants while acquiring high resolution EEG data. The stimuli were either consciously detectable (supraliminal presentations) or were rendered non-conscious through backward masking (subliminal presentations). The N1 event-related potential component was significantly enhanced in participants when they viewed naked compared to dressed bodies under supraliminal viewing conditions. More importantly, naked bodies of the opposite sex produced a significantly greater N1 component compared to dressed bodies during subliminal presentations, when participants were not aware of the stimulus presented. A source localization algorithm computed on the N1 showed that the response for naked bodies in the supraliminal viewing condition was stronger in body processing areas, primary visual areas and additional structures related to emotion processing. By contrast, in the subliminal viewing condition, only visual and body processing areas were found to be activated. These results suggest that naked bodies and primary sexual characteristics are processed early in time (i.e., sexual features benefit from automatic and rapid processing, most likely due to their high relevance for the individual and their importance for the species in terms of reproductive success. PMID:23894532

Spectral properties of superpositions of Ornstein-Uhlenbeck type processes

DEFF Research Database (Denmark)

Barndorff-Nielsen, Ole Eiler; Leonenko, N.N.

2005-01-01

Stationary processes with prescribed one-dimensional marginal laws and long-range dependence are constructed. The asymptotic properties of the spectral densities are studied. The possibility of Mittag-Leffler decay in the autocorrelation function of superpositions of Ornstein-Uhlenbeck type...... processes is proved....

Improved cracking characteristics of bitumen through advanced froth treatment process

Energy Technology Data Exchange (ETDEWEB)

Ng, S.H. [National Centre for Upgrading Technology, Devon, AB (Canada); Dabros, T. [Natural Resources Canada, Devon, AB (Canada). CANMET Advanced Separation Technologies Laboratory; Humphries, A. [Albemarle Catalysts Co., Houston, TX (United States)

2006-07-01

Fluid catalytic cracking (FCC) is the dominant refinery conversion process for producing transportation fuels. Feed to the FCC unit is heavy gas oil (HGO). Its quality depends on the crude used and the processes involved. Bitumen-derived crude (BDC), including synthetic crude oil (SCO) is less superior to produce FCC feed than stocks from conventional sources. As a result, North American refiners have limited the use of BDC in their conventional FCC-based operations. This paper examined the improved cracking characteristics of bitumen through an advanced froth treatment process. This involved processing of the bitumen with paraffinic solvent in froth treatment with removal of some asphaltenes, CCR precursors, and metals. The paper discussed the experimental and subsequent results and discussion, including cracking characteristics; product quality; synergetic effect; and economic benefits. It was concluded that the poisoning effect by some deleterious components such as nitrogen compounds in feeds on the catalyst could be reduced or compensated for by higher C/O ratios (more catalyst per unit weight of feed). In addition, as conversion increased, sulfur in gasoline decreased slightly and linearly with more or less the same magnitude for the two bitumens. 5 refs., 1 tab., 3 figs.

Stationary and related stochastic processes sample function properties and their applications

CERN Document Server

Cramér, Harald

2004-01-01

This graduate-level text offers a comprehensive account of the general theory of stationary processes, with special emphasis on the properties of sample functions. Assuming a familiarity with the basic features of modern probability theory, the text develops the foundations of the general theory of stochastic processes, examines processes with a continuous-time parameter, and applies the general theory to procedures key to the study of stationary processes. Additional topics include analytic properties of the sample functions and the problem of time distribution of the intersections between a

Chemical characteristic and functional properties of arenga starch-taro (Colocasia esculanta L.) flour noodle with turmeric extracts addition

Science.gov (United States)

Ervika Rahayu N., H.; Ariani, Dini; Miftakhussolikhah, E., Maharani P.; Yudi, P.

2017-01-01

Arenga starch-taro (Colocasia esculanta L.) flour noodle is an alternative carbohydrate source made from 75% arenga starch and 25% taro flour, but it has a different color with commercial noodle product. The addition of natural color from turmeric may change the consumer preference and affect chemical characteristic and functional properties of noodle. This research aims to identify chemical characteristic and functional properties of arenga starch-taro flour noodle with turmeric extract addition. Extraction was performed using 5 variances of turmeric rhizome (0.06; 0.12; 0.18; 0.24; and 0.30 g (fresh weight/ml water). Then, noodle was made and chemical characteristic (proximate analysis) as well as functional properties (amylose, resistant starch, dietary fiber, antioxidant activity) were then evaluated. The result showed that addition of turmeric extract did not change protein, fat, carbohydrate, amylose, and resistant starch content significantly, while antioxidant activity was increased (23,41%) with addition of turmeric extract.

Effect of biometric characteristics on biomechanical properties of the cornea in cataract patient.

Science.gov (United States)

Song, Xue-Fei; Langenbucher, Achim; Gatzioufas, Zisis; Seitz, Berthold; El-Husseiny, Moatasem

2016-01-01

To determine the impact of biometric characteristics on the biomechanical properties of the human cornea using the ocular response analyzer (ORA) and standard comprehensive ophthalmic examinations before and after standard phacoemulsification. This study comprised 54 eyes with cataract with significant lens opacification in stages I or II that underwent phacoemulsification (2.8 mm incision). Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) were measured by ORA preoperatively and at 1mo postoperatively. Biometric characteristics were derived from corneal topography [TMS-5, anterior equivalent (EQTMS) and cylindric (CYLTMS) power], corneal tomography [Casia, anterior and posterior equivalent (EQaCASIC, EQpCASIA) and cylindric (CYLaCASIA, CYLpCASIA) power], keratometry [IOLMaster, anterior equivalent (EQIOL) and cylindric (CYLIOL) power] and autorefractor [anterior equivalent (EQAR)]. Results from ORA were analyzed and correlated with those from all other examinations taken at the same time point. Preoperatively, CH correlated with EQpCASIA and CYLpCASIA only (P=0.001, P=0.002). Postoperatively, IOPg and IOPcc correlated with all equivalent powers (EQTMS, EQIOL, EQAR, EQaCASIA and EQpCASIA) (P=0.001, P=0.007, P=0.001, P=0.015, P=0.03 for IOPg and PBiometric characteristics may significantly affect biomechanical properties of the cornea in terms of CH, IOPcc and IOPg before, but even more after cataract surgery.

Transient internal characteristic study of a centrifugal pump during startup process

International Nuclear Information System (INIS)

Hu, F F; Ma, X D; Wu, D Z; Wang, L Q

2012-01-01

The transient process of a centrifugal pump existed in a variety of occasions. There were a lot of researches in the external characteristic in startup process and stopping process, but internal characteristics were less observed and studied. Study of the internal flow field had significant meanings. The performance of a pump could be evaluated and improved by revealing the flow field. In the other hand, the prediction of external characteristic was based on the correct analysis of the internal flow. In this paper, theoretical method and numerical simulation were used to study the internal characteristic of a centrifugal pump. The theoretical study showed that the relative flow in an impeller was composed of homogeneous flow and axial vortex flow. The vortex intensity was mainly determined by angular velocity of impeller, flow channel width and blade curvature. In order to get the internal flow field and observe the evolution of transient internal flow in the impeller, Computational Fluid Dynamics(CFD) were used to study the three-dimensional unsteady incompressible viscous flows in a centrifugal pump during starting period. The Dynamic Mesh (DM) method with non-conformal grid boundaries was applied to get the external characteristic and internal flow field. The simulate model included three pumps with different blade numbers and the same blade curvature. The relative velocity vector showed that there was a big axial vortex in impeller channel. At the beginning, the vortex was raised in the pressure side of the impeller outlet and with time went on, it shifted to the middle flow channel of the impeller and the vortex intensity increased. When the speed and flow rate reached a definite value, the influence of the axial vortex began to get smaller. The vortex developed faster when the flow channel got narrower. Due to the evolution of axial vortex, the slip factor during starting period was smaller than that in quasi-steady condition. As a result, transient head was

Chemical Properties and Characteristics of Cow Milk Yogurt with Different Additional Fruit and Storage Time

Directory of Open Access Journals (Sweden)

Putri Dian Wulansari

2016-05-01

Full Text Available This research was aimed to evaluate the composition (total solids, water content, fat and protein, qualitative properties (color, aroma, and texture and quantitative properties (free fatty acid and lactic acid of cow milk yogurt with different fruits addition and storage time. Experimental method applied Completely Randomized Design with five treatments namely control, dragon fruit, mango, apple and banana (20% v/v, each with 5 replicates. Qualitative characteristic assessment was conducted on 0, 5, 10 and 15 days of storage. Result showed that fruit addition significantly affected the composition and characteristics, while storage time significantly affected quantitative characteristics of yogurt. Apple and banana increased 13% total solids of plain yogurt, while the highest fat content (4,516% was observed in control yogurt which had the lowest protein content (2,564. The highest free fatty acid  was in control yogurt ripen for 15 days (22,885% while the lowest free fatty acid was in mango yogurt ripen for 10 days (13,915%. Fruit addition in yogurt ripen for 15 days at 5C resulted in a safe consumed product.

Damage characteristics and thermo-physical properties changes of limestone and sandstone during thermal treatment from -30 °C to 1000 °C

Science.gov (United States)

Shen, Yanjun; Yang, Yang; Yang, Gengshe; Hou, Xin; Ye, Wanjun; You, Zhemin; Xi, Jiami

2018-05-01

A series of experiments were carried out to measure the damage characteristics of two common sedimentary rocks of limestone and sandstone at temperatures ranging from -30 °C to 1000 °C The apparent thermal conductivity, thermal diffusivity and specific heat capacity were investigated respectively. Then, several discrepancy reasons for the damage characteristics and thermo-physical properties of limestone and sandstone were probed. The results show that water migration and phase transition are two core factors for the frost damage and thermal behaviors improvement during the cooling process(20 °C → -30 °C).The heating process (20 °C → 1000 °C) was divided into three stages of 20 °C → 200 °C, 200 °C → 600 °Cand 600 °C → 1000 °C. The first stage was closely related to pore-water evaporation, and the next two stages were attributed to the thermal reactions of mineral partials. The mineral decomposition tended to be intensified and resulted in the interior damage or even the accelerated degradation of thermal properties until at a threshold temperature of 600 °C. In essential, the structural features and the sensitivity of mineral composition to temperature were two mainly influential factors on the damage effects and heat conduct of the sedimentary rocks during variations in environmental temperature.

Powder processing of high Tc oxide superconductors and their properties

International Nuclear Information System (INIS)

Vajpei, A.C.; Upadhyaya, G.S.

1992-01-01

Powder processing of ceramics is an established technology and in the area of high T c superconductors, its importance is felt even more significantly. The present monograph is an attempt in this direction to explore the perspectives and practice of powder processing routes towards control and optimization of the microstructure and pertinent properties of high T c oxide superconductors. The monograph consists of 6 chapters. After a very brief introduction (Chapter 1), Chapter 2 describes various classes of high T c oxide superconductors and their phase equilibria. Chapter 3 highlights the preparation of oxide superconductor powders through various routes and details their subtle distinctions. Chapter 4 briefly covers characterisation of the oxide superconductors, laying emphasis on the process-analysis and microstructure. Chapter 5 describes in detail various fabrication techniques for bulk superconductors through the powder routes. The last Chapter (Chapter 6) describing properties of bulk oxide superconductors, discusses the role of subtituents, compositional variations and processing methods on such properties. References are given at the end of each chapter. (orig.)

Sensitivity of Process Design due to Uncertainties in Property Estimates

DEFF Research Database (Denmark)

Hukkerikar, Amol; Jones, Mark Nicholas; Sarup, Bent

2012-01-01

The objective of this paper is to present a systematic methodology for performing analysis of sensitivity of process design due to uncertainties in property estimates. The methodology provides the following results: a) list of properties with critical importance on design; b) acceptable levels of...... in chemical processes. Among others vapour pressure accuracy for azeotropic mixtures is critical and needs to be measured or estimated with a ±0.25% accuracy to satisfy acceptable safety levels in design....

Influence of process parameters and biomass characteristics on the durability of pellets from the pruning residues of Olea europaea L.

Energy Technology Data Exchange (ETDEWEB)

Carone, Maria Teresa; Pantaleo, Antonio; Pellerano, Achille [Department of Engineering and Management of the Agricultural, Livestock and Forest Systems, Faculty of Agriculture, University of Bari, Via Amendola, 165/A, 70126 Bari (Italy)

2011-01-15

The present work aims to investigate the influence of the main process parameters (pressure and temperature) and biomass characteristics (moisture content and particle size) on some mechanical properties (density and durability) of olive tree pruning residues pellets. By means of a lab scale pellet press, able to control process parameters, the biomass, ground with three different hammer mill screen sizes (1, 2 and 4 mm) and conditioned at different moisture contents (5, 10, 15 and 20% w.b.), was pelletized at various process temperatures (60, 90, 120 and 150 C) and pressures (71, 106, 141 and 176 MPa). Compressed sample dimensions and mass were measured in order to calculate pellet density, while compressive strength tests were carried out to estimate the durability of the final biofuel. The relationships between the factor settings and the responses (density, compression strength and modulus of elasticity) were examined by univariate and multivariate statistical analysis. Temperature resulted the most important variable influencing pellet mechanical properties, followed by the initial moisture content and the particle size of the raw material. In particular, high process temperature, low moisture contents and reduced particle sizes allowed obtaining good quality pellets. The effect of compression force resulted scarcely relevant. (author)

Characteristics of SiC neutron sensor spectrum unfolding process based on Bayesian inference

Energy Technology Data Exchange (ETDEWEB)

Cetnar, Jerzy; Krolikowski, Igor [Faculty of Energy and Fuels AGH - University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow (Poland); Ottaviani, L. [IM2NP, UMR CNRS 7334, Aix-Marseille University, Case 231 -13397 Marseille Cedex 20 (France); Lyoussi, A. [CEA, DEN, DER, Instrumentation Sensors and Dosimetry Laboratory, Cadarache, F-13108 St-Paul-Lez-Durance (France)

2015-07-01

This paper deals with SiC detector signal interpretation in neutron radiation measurements in mixed neutron gamma radiation fields, which is called the detector inverse problem or the spectrum unfolding, and it aims in finding a representation of the primary radiation, based on the measured detector signals. In our novel methodology we resort to Bayesian inference approach. In the developed procedure the resultant spectra is unfolded form detector channels reading, where the estimated neutron fluence in a group structure is obtained with its statistical characteristic comprising of standard deviation and correlation matrix. In the paper we present results of unfolding process for case of D-T neutron source in neutron moderating environment. Discussions of statistical properties of obtained results are presented as well as of the physical meaning of obtained correlation matrix of estimated group fluence. The presented works has been carried out within the I-SMART project, which is part of the KIC InnoEnergy R and D program. (authors)

Plasma sprayed thermal barrier coatings for industrial gas turbines: morphology, processing and properties

International Nuclear Information System (INIS)

Gruenling, H.W.; Mannsmann, W.

1993-01-01

Thermal barrier coatings out of fully or partially stabilized zirconia offer a unique chance in gas turbines to increase the gas inlet temperature significantly while keeping the temperature of the structural material of the component within conventional limits. The protection of combustor parts and transition pieces as well as of some stationary gas turbine parts however is state of the art. As a consequence of still insufficient reliability, the application for hot rotating parts is very limited. The introduction as a design element requires safe life within defined time intervals. These depend on the overhaul and repair intervals of the engines. For large land based industrial or utility gas turbines, for example, coating life between 25.000 and 30.000 hrs. is a minimum requirement. Premature failure of a coating by e.g. local spalling causes local overheating of the component with the consequence of its total destruction or even more expensive secondary damages. Life limiting is the corrosion rate at the ceramic-metal interface and the behavior of the coated system under transient operating conditions, where multiaxial strain and stress distributions are generated. Sufficient strain tolerance of the coating both under tensile as well as compressive conditions is required. The properties of thermal barrier coating systems depend strongly on the structure and phase composition of the coating layers and the morphology of and the adhesion at the ceramic-metal interface. They have to be controlled by the process itself, the process parameters and the characteristics of the applied materials (e.g. chemical composition, processing, morphology, particle size and size distribution). It will be reviewed, how properties and structures of coating systems correlate and how structures can be modified by careful control of the process parameters. (orig.)

Structure, health benefits, antioxidant property and processing and ...

African Journals Online (AJOL)

Structure, health benefits, antioxidant property and processing and storage of carotenoids. ... It is sensitive to heat, light and oxygen. Enzymatic ... Thermal treatment and freezing increases the extractability of b-carotene from the food matrices.

Impact of food processing on rye product properties and their in vitro digestion.

Science.gov (United States)

Johansson, Daniel P; Gutiérrez, José L Vázquez; Landberg, Rikard; Alminger, Marie; Langton, Maud

2018-06-01

Rye products have been reported to elicit postprandial insulin and glucose responses which may be beneficial for prevention of type-2 diabetes. However, mechanisms underlying variations in responses related to processing techniques are not fully understood. Five differently processed rye products (sourdough-fermented bread, fermented and unfermented crispbread, extrusion-cooked rye, and porridge) and refined wheat bread were characterised. Two in vitro methods, a dynamic method simulating digestion in the stomach and small intestine and a static method, simulating conditions in the stomach were used to determine viscosity development, structural changes and release of glucose during digestion. Structural and compositional differences induced by processing influenced product digestion. Gastric disintegration and digesta particle size were related to characteristics of the starch/protein matrix, while digesta viscosity was reduced due to fibre degradation during fermentation. More cohesive boluses were associated with slower glucose release. Sourdough fermentation increased amylose leakage and appeared to inhibit starch hydrolysis despite low digesta viscosity and rapid disintegration. The net release of glucose during digestion of foods is determined by several factors which may vary in their importance depending on product specific properties.

ODS steel fabrication: relationships between process, microstructure and mechanical properties

International Nuclear Information System (INIS)

Couvrat, M.

2011-01-01

Oxide Dispersion Strengthened (ODS) steels are promising candidate materials for generation IV and fusion nuclear energy systems thanks to their excellent thermal stability, high-temperature creep strength and good irradiation resistance. Their superior properties are attributed both to their nano-structured matrix and to a high density of Y-Ti-O nano-scale clusters (NCs). ODS steels are generally prepared by Mechanical Alloying of a pre-alloyed Fe-Cr-W-Ti powder with Y 2 O 3 powder. A fully dense bar or tube is then produced from this nano-structured powder by the mean of hot extrusion. The aim of this work was to determine the main parameters of the process of hot extrusion and to understand the link between the fabrication process, the microstructure and the mechanical properties. The material microstructure was characterized at each step of the process and bars were extruded with varying hot extrusion parameters so as to identify the impact of these parameters. Temperature then appeared to be the main parameter having a great impact on microstructure and mechanical properties of the extruded material. We then proposed a cartography giving the microstructure versus the process parameters. Based on these results, it is possible to control very accurately the obtained material microstructure and mechanical properties setting the extrusion parameters. (author) [fr

Exploring the Impact of Electronic Word of Mouth and Property Characteristics on Customers’ Online Booking Decision

Directory of Open Access Journals (Sweden)

Aeshah A. Alabdullatif

2018-05-01

Full Text Available The proliferation of the internet has helped many businesses to attract potential customers from traditional to the online channel. The customers’ decision making on the online channel is affected by various factors such as other customer reviews, website quality, and property characteristics as well as customers personal profile. In this context, this study investigates the role of online customer reviews and key elements of the reviews page, particularly the elements that are poorly investigated in previous, as well as property characteristics in customers’ online hotel booking decision. A conceptual model has been proposed to measure the impact of these factors on customers decision making. The model is empirically tested with a data obtained from customers of booking.com having various backgrounds and nationalities. Structural Equation Modelling using SmartPLS 3.2 has been used to test the relationships in the suggested model. The results show a significant impact of online review factors such as filters, quality, quantity, recency, valence along with property characteristics on customers booking decision. The study also confirms the moderating effects of Gender and Travel Purpose on some of the proposed relationships in the conceptual model. The paper concludes by mentioning the limitations and recommendations for future work as well as implications for the academicians and managers.

Experimental study on spray characteristics of alternate jet fuels using Phase Doppler Anemometry

Science.gov (United States)

Kannaiyan, Kumaran; Sadr, Reza

2013-11-01

Gas-to-Liquid (GTL) fuels have gained global attention due to their cleaner combustion characteristics. The chemical and physical properties of GTL jet fuels are different from conventional jet fuels owing to the difference in their production methodology. It is important to study the spray characteristics of GTL jet fuels as the change of physical properties can affect atomization, mixing, evaporation and combustion process, ultimately affecting emission process. In this work, spray characteristics of two GTL synthetic jet fuels are studied using a pressure-swirl nozzle at different injection pressures and atmospheric ambient condition. Phase Doppler Anemometry (PDA) measurements of droplet size and velocity are compared with those of regular Jet A-1 fuel at several axial and radial locations downstream of the nozzle exit. Experimental results show that although the GTL fuels have different physical properties such as viscosity, density, and surface tension, among each other the resultant change in the spray characteristics is insignificant. Furthermore, the presented results show that GTL fuel spray characteristics exhibit close similarity to those of Jet A-1 fuel. Funded by Qatar Science and Technology Park.

TOPICAL REVIEW Textured silicon nitride: processing and anisotropic properties

Directory of Open Access Journals (Sweden)

Xinwen Zhu and Yoshio Sakka

2008-01-01

Full Text Available Textured silicon nitride (Si3N4 has been intensively studied over the past 15 years because of its use for achieving its superthermal and mechanical properties. In this review we present the fundamental aspects of the processing and anisotropic properties of textured Si3N4, with emphasis on the anisotropic and abnormal grain growth of β-Si3N4, texture structure and texture analysis, processing methods and anisotropic properties. On the basis of the texturing mechanisms, the processing methods described in this article have been classified into two types: hot-working (HW and templated grain growth (TGG. The HW method includes the hot-pressing, hot-forging and sinter-forging techniques, and the TGG method includes the cold-pressing, extrusion, tape-casting and strong magnetic field alignment techniques for β-Si3N4 seed crystals. Each processing technique is thoroughly discussed in terms of theoretical models and experimental data, including the texturing mechanisms and the factors affecting texture development. Also, methods of synthesizing the rodlike β-Si3N4 single crystals are presented. Various anisotropic properties of textured Si3 N4 and their origins are thoroughly described and discussed, such as hardness, elastic modulus, bending strength, fracture toughness, fracture energy, creep behavior, tribological and wear behavior, erosion behavior, contact damage behavior and thermal conductivity. Models are analyzed to determine the thermal anisotropy by considering the intrinsic thermal anisotropy, degree of orientation and various microstructure factors. Textured porous Si3N4 with a unique microstructure composed of oriented elongated β-Si3N4 and anisotropic pores is also described for the first time, with emphasis on its unique mechanical and thermal-mechanical properties. Moreover, as an important related material, textured α-Sialon is also reviewed, because the presence of elongated α-Sialon grains allows the production of textured �

Metformin: A Review of Characteristics, Properties, Analytical Methods and Impact in the Green Chemistry.

Science.gov (United States)

da Trindade, Mariana Teixeira; Kogawa, Ana Carolina; Salgado, Hérida Regina Nunes

2018-01-02

Diabetes mellitus (DM) is considered a public health problem. The initial treatment consists of improving the lifestyle and making changes in the diet. When these changes are not enough, the use of medication becomes necessary. The metformin aims to reduce the hepatic production of glucose and is the preferred treatment for type 2. The objective is to survey the characteristics and properties of metformin, as well as hold a discussion on the existing analytical methods to green chemistry and their impacts for both the operator and the environment. For the survey, data searches were conducted by scientific papers in the literature as well as in official compendium. The characteristics and properties are shown, also, methods using liquid chromatography techniques, titration, absorption spectrophotometry in the ultraviolet and the infrared region. Most of the methods presented are not green chemistry oriented. It is necessary the awareness of everyone involved in the optimization of the methods applied through the implementation of green chemistry to determine the metformin.

The study of polymeric hydro-gels with unique properties obtained by polymerization with gamma radiation processing

International Nuclear Information System (INIS)

Dragusin, M.

1995-01-01

This thesis presents the work carried out on polymeric hydro-gels obtained by radiation processing using 60 Co gamma rays from the irradiation facility IETI-10.000 (10 k Ci), and on the polymeric hydro-gels obtained by irradiation with the electron beams from a linear accelerator (6 MeV). The aim of the study was to determine the effect of the rate dose and total dose absorbed in the materials. There are presented the preparation methods of homo- and co-polymer hydro-gels (acrylics, namely anionic and neutral monomers (acrylamide, acrylic acid, vinyl acetate) and cationic monomers (di-methyl di-allyl ammonium chloride)) such as floculants, additives, absorbers, etc. Concerning with these we have analysed the preparation methods, the mechanical, thermal, diffusivity, and swelling properties of polymeric hydro-gels in a large variety of gels of type I or II. The technological aspects and end use were studied in connection with the characteristics of the radiation processing of these hydro-gels as a function of chemical composition rate and absorbed dose, swelling degree (low and very high hydro-soluble), mechanical and diffusional properties. (author) 33 figs., 12 tabs., 101 refs

Effect of food processing on the physicochemical properties of dietary fibre.

Science.gov (United States)

Ozyurt, Vasfiye Hazal; Ötles, Semih

2016-01-01

Products derived from the manufacturing or processing of plant based foods: cereals, fruits, vegetables, as well as algae, are sources of abundant dietary fibre. Diets high in dietary fibre have been associated with the reduced risk of cardiovascular disease, diabetes, hypertension, obesity, and gastrointestinal disorders. These fibre-rich products and byproducts can also fortify foods, increase their dietary fibre content and result in healthy products, low in calories, cholesterol and fat. Traditionally, consumers have chosen foods such as whole grains, fruits and vegetables as sources of dietary fibre. Recently, food manufacturers have responded to consumer demand for foods with a higher fibre content by developing products in which highfibre ingredients are used. Different food processing methods also increase the dietary fiber content of food. Moreover, its chemical and physical properties may be affected by food processing. Some of them might even improve the functionality of fibre. Therefore, they may also be applied as functional ingredients to improve physical properties like the physical and structural properties of hydration, oil-holding capacity, viscosity. This study was conducted to examine the effect of different food processing methods on the physicochemical properties of dietary fibre.

Impact of process temperature on GaSb metal-oxide-semiconductor interface properties fabricated by ex-situ process

Energy Technology Data Exchange (ETDEWEB)

Yokoyama, Masafumi, E-mail: yokoyama@mosfet.t.u-tokyo.ac.jp; Takenaka, Mitsuru; Takagi, Shinichi [Department of Electrical Engineering and Information Systems, The University of Tokyo, Yayoi 2-11-16, Bunkyo, Tokyo 113-0032 (Japan); JST-CREST, Yayoi 2-11-16, Bunkyo, Tokyo 113-0032 (Japan); Asakura, Yuji [Department of Electrical Engineering and Information Systems, The University of Tokyo, Yayoi 2-11-16, Bunkyo, Tokyo 113-0032 (Japan); Yokoyama, Haruki [NTT Photonics Laboratories, NTT Corporation, Atsugi 243-0198 (Japan)

2014-06-30

We have studied the impact of process temperature on interface properties of GaSb metal-oxide-semiconductor (MOS) structures fabricated by an ex-situ atomic-layer-deposition (ALD) process. We have found that the ALD temperature strongly affects the Al{sub 2}O{sub 3}/GaSb MOS interface properties. The Al{sub 2}O{sub 3}/GaSb MOS interfaces fabricated at the low ALD temperature of 150 °C have the minimum interface-trap density (D{sub it}) of ∼4.5 × 10{sup 13 }cm{sup −2} eV{sup −1}. We have also found that the post-metalization annealing at temperature higher than 200 °C degrades the Al{sub 2}O{sub 3}/GaSb MOS interface properties. The low-temperature process is preferable in fabricating GaSb MOS interfaces in the ex-situ ALD process to avoid the high-temperature-induced degradations.

Oral processing characteristics of solid savoury meal components, and relationship with food composition, sensory attributes and expected satiation.

Science.gov (United States)

Forde, C G; van Kuijk, N; Thaler, T; de Graaf, C; Martin, N

2013-01-01

The modern food supply is often dominated by a large variety of energy dense, softly textured foods that can be eaten quickly. Previous studies suggest that particular oral processing characteristics such as large bite size and lack of chewing activity contribute to the low satiating efficiency of these foods. To better design meals that promote greater feelings of satiation, we need an accurate picture of the oral processing characteristics of a range of solid food items that could be used to replace softer textures during a normal hot meal. The primary aim of this study was to establish an accurate picture of the oral processing characteristics of a set of solid savoury meal components. The secondary aim was to determine the associations between oral processing characteristics, food composition, sensory properties, and expected satiation. In a within subjects design, 15 subjects consumed 50 g of 35 different savoury food items over 5 sessions. The 35 foods represented various staples, vegetables and protein rich foods such a meat and fish. Subjects were video-recorded during consumption and measures included observed number of bites, number of chews, number of swallows and derived measures such as chewing rate, eating rate, bite size, and oral exposure time. Subjects rated expected satiation for a standard 200 g portion of each food using a 100mm and the sensory differences between foods were quantified using descriptive analysis with a trained sensory panel. Statistical analysis focussed on the oral processing characteristics and associations between nutritional, sensory and expected satiation parameters of each food. Average number of chews for 50 g of food varied from 27 for mashed potatoes to 488 for tortilla chips. Oral exposure time was highly correlated with the total number of chews, and varied from 27 s for canned tomatoes to 350 s for tortilla chips. Chewing rate was relatively constant with an overall average chewing rate of approximately 1 chew

Supplementary effects of higher levels of various disaccharides on processing yield, quality properties and sensory attributes of Chinese - style pork jerky.

Science.gov (United States)

Chen, Chih-Ming; Lin, Hsien-Tang

2017-12-01

This study evaluated the supplementary effect of higher concentrations of various disaccharides on processing yield, major physicochemical properties, and sensory attributes of Chinese-style pork jerky (CSPJ). CSPJ samples were prepared by marinating sliced ham (4 mm) with three dissaccharides, including sucrose, lactose, and maltose, at 0%, 15%, 18%, 21%, and 24%. Subsequently, the CSPJ samples were dried and roasted. The moisture content, water activity, crude protein, moisture-to-protein ratio, pH, processing yield, shear force, color, and sensory attributes of the CSPJ samples were evaluated. The quality characteristics of CSPJ samples prepared with sucrose were more acceptable. By contrast, CSPJ samples prepared with lactose showed the lowest scores. However, the processing yield and moisture content were the highest for CSPJ samples prepared with lactose, which may be associated with improved benefits for cost reduction. Furthermore, sucrose and lactose supplementation resulted in contrasting quality characteristics; for example, CSPJ samples with sucrose and maltose supplementation had higher sensory scores for color than samples with lactose supplementation. Additionally, most quality characteristics of CSPJ samples with sucrose supplementation contrasted with those of the samples with lactose supplementation; for example, the samples with sucrose supplementation had higher scores for sensory attributes than those with lactose supplementation. Sucrose supplementation up to 21% to 24% was associated with the highest overall acceptability scores (5.19 to 5.80), enhanced quality characteristics, increased processing yield, and reduced production cost.

Supplementary effects of higher levels of various disaccharides on processing yield, quality properties and sensory attributes of Chinese - style pork jerky

Directory of Open Access Journals (Sweden)

Chih-Ming Chen

2017-12-01

Full Text Available Objective This study evaluated the supplementary effect of higher concentrations of various disaccharides on processing yield, major physicochemical properties, and sensory attributes of Chinese-style pork jerky (CSPJ. Methods CSPJ samples were prepared by marinating sliced ham (4 mm with three dissaccharides, including sucrose, lactose, and maltose, at 0%, 15%, 18%, 21%, and 24%. Subsequently, the CSPJ samples were dried and roasted. The moisture content, water activity, crude protein, moisture-to-protein ratio, pH, processing yield, shear force, color, and sensory attributes of the CSPJ samples were evaluated. Results The quality characteristics of CSPJ samples prepared with sucrose were more acceptable. By contrast, CSPJ samples prepared with lactose showed the lowest scores. However, the processing yield and moisture content were the highest for CSPJ samples prepared with lactose, which may be associated with improved benefits for cost reduction. Furthermore, sucrose and lactose supplementation resulted in contrasting quality characteristics; for example, CSPJ samples with sucrose and maltose supplementation had higher sensory scores for color than samples with lactose supplementation. Additionally, most quality characteristics of CSPJ samples with sucrose supplementation contrasted with those of the samples with lactose supplementation; for example, the samples with sucrose supplementation had higher scores for sensory attributes than those with lactose supplementation. Conclusion Sucrose supplementation up to 21% to 24% was associated with the highest overall acceptability scores (5.19 to 5.80, enhanced quality characteristics, increased processing yield, and reduced production cost.

Comparison of the effects of different heat treatment processes on rheological properties of cake and bread wheat flours.

Science.gov (United States)

Bucsella, Blanka; Takács, Ágnes; Vizer, Viktoria; Schwendener, Urs; Tömösközi, Sándor

2016-01-01

Dry and hydrothermal heat treatments are efficient for modifying the technological-functional and shelf-life properties of wheat milling products. Dry heat treatment process is commonly used to enhance the volume of cakes. Hydrothermal heat treatment makes wheat flours suitable as thickener agents. In this study, cake and bread wheat flours that differed in baking properties were exposed to dry (100 °C, 12 min) and hydrothermal (95 °C, 5 min, 5-20 l/h water) heat treatments. Rheological differences caused by the treatments were investigated in a diluted slurry and in a dough matrix. Dry heat treatment resulted in enhanced dough stability. This effect was significantly higher in the cake flour than the bread flour. Altered viscosity properties of the bread flour in the slurry matrix were also observed. The characteristics of hydrothermally treated samples showed matrix dependency: their viscosity increases in the slurry and decreases in the dough matrix. These results can support us to produce flour products with specific techno-functional properties. Copyright © 2015 Elsevier Ltd. All rights reserved.

Thermal characteristics during hydrogen fueling process of type IV cylinder

Energy Technology Data Exchange (ETDEWEB)

Kim, Sung Chan [Department of Fire and Disaster Prevention, Kyungil University, 33, Buhori, Hayang, Kyungsan 712-701 (Korea); Lee, Seung Hoon; Yoon, Kee Bong [Department of Mechanical Engineering, Chung Ang University, 221, Huksuk, Dongjak, Seoul 156-756 (Korea)

2010-07-15

Temperature increase during hydrogen fueling process is a significant safety concern of a high pressure hydrogen vessel. Hence, thermal characteristics of a Type IV cylinder during hydrogen filling process need to be understood. In this study, a series of experiments were conducted to quantify the temperature change of the cylinder during hydrogen filling to 35 MPa. Computational fluid dynamics (CFD) analysis was also conducted to simulate the conditions of the experiments. The results predicted by the CFD analysis show reasonable agreement with the experiments and the discrepancy between the CFD results and experimental results decrease with higher initial gas pressures. The upper and the lower parts of the vessel showed a temperature difference in the vertical direction. The upper gas temperature was higher than that of the lower part due to the buoyancy effect in the vessel. The maximum gas temperature was higher than the maximum temperature allowed in the ISO safety code (85 C) for the case in which the vessel was pressurized from 0 MPa to 35 MPa. This work contributes to the understanding of the thermal flow characteristics of the hydrogen filling process and notes that additional efforts should be made to guarantee the safety of a type IV cylinder during the hydrogen fueling process. (author)

Process, Structure, and Properties of Electrospun Carbon Nanotube-Reinforced Nanocomposite Yarns

Directory of Open Access Journals (Sweden)

Nasir M. Uddin

2009-01-01

Full Text Available Carbon nanotubes (CNTs are dispersed into polyacrylonitrile polymer solution and then assembled into continuous nanocomposite yarns through the drum-tape co-electrospinning process to facilitate the translation of CNT properties to higher order structures. We explore the dispersion of CNTs in a polymer matrix, the process of obtaining continuous yarn through electrospinning, and the surface morphology and mechanical properties of the nanocomposite yarn.

Chemical constituents of Sweetpotato genotypes in relation to textural characteristics of processed French fries

Science.gov (United States)

Sweetpotato French fries (SPFF) are growing in popularity but limited information is available on SPFF textural properties in relation to chemical composition. This study aimed to investigate the relationship between chemical components of different sweetpotato varieties and textural characteristics...

Influence of Chemical Blends on Palm Oil Methyl Esters’ Cold Flow Properties and Fuel Characteristics

Directory of Open Access Journals (Sweden)

Obed M. Ali

2014-07-01

Full Text Available Alternative fuels, like biodiesel, are being utilized as a renewable energy source and an effective substitute for the continuously depleting supply of mineral diesel as they have similar combustion characteristics. However, the use of pure biodiesel as a fuel for diesel engines is currently limited due to problems relating to fuel properties and its relatively poor cold flow characteristics. Therefore, the most acceptable option for improving the properties of biodiesel is the use of a fuel additive. In the present study, the properties of palm oil methyl esters with increasing additive content were investigated after addition of ethanol, butanol and diethyl ether. The results revealed varying improvement in acid value, density, viscosity, pour point and cloud point, accompanied by a slight decrease in energy content with an increasing additive ratio. The viscosity reductions at 5% additive were 12%, 7%, 16.5% for ethanol, butanol and diethyl ether, respectively, and the maximum reduction in pour point was 5 °C at 5% diethyl ether blend. Engine test results revealed a noticeable improvement in engine brake power and specific fuel consumption compared to palm oil biodiesel and the best performance was obtained with diethyl ether. All the biodiesel-additive blend samples meet the requirements of ASTM D6751 biodiesel fuel standards for the measured properties.

Outstanding field emission properties of wet-processed titanium dioxide coated carbon nanotube based field emission devices

Energy Technology Data Exchange (ETDEWEB)

Xu, Jinzhuo; Ou-Yang, Wei, E-mail: ouyangwei@phy.ecnu.edu.cn; Chen, Xiaohong; Guo, Pingsheng; Piao, Xianqing; Sun, Zhuo [Engineering Research Center for Nanophotonics and Advanced Instrument, Ministry of Education, Department of Physics, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062 (China); Xu, Peng; Wang, Miao [Department of Physics, Zhejiang University, 38 ZheDa Road, Hangzhou 310027 (China); Li, Jun [Department of Electronic Science and Technology, Tongji University, 4800 Caoan Road, Shanghai 201804 (China)

2015-02-16

Field emission devices using a wet-processed composite cathode of carbon nanotube films coated with titanium dioxide exhibit outstanding field emission characteristics, including ultralow turn on field of 0.383 V μm{sup −1} and threshold field of 0.657 V μm{sup −1} corresponding with a very high field enhancement factor of 20 000, exceptional current stability, and excellent emission uniformity. The improved field emission properties are attributed to the enhanced edge effect simultaneously with the reduced screening effect, and the lowered work function of the composite cathode. In addition, the highly stable electron emission is found due to the presence of titanium dioxide nanoparticles on the carbon nanotubes, which prohibits the cathode from the influence of ions and free radical created in the emission process as well as residual oxygen gas in the device. The high-performance solution-processed composite cathode demonstrates great potential application in vacuum electronic devices.

Effect of Processing Steps on the Mechanical Properties and Surface Appearance of 6063 Aluminium Extruded Products

Science.gov (United States)

Asensio-Lozano, Juan; Suárez-Peña, Beatriz; Vander Voort, George F.

2014-01-01

6063 aluminum anodized extrusions may exhibit a common surface defect known as streaking, characterized by the formation of narrow bands with a surface gloss different from the surrounding material. The origin of this banding lies in the differential surface topography produced after etching during the anodizing stage, shown to be connected to certain microstructural characteristics. The present study has attempted to determine the origin of these defects and measure the mechanical properties in these zones, properties which were either barely acceptable or did not meet the specification’s requirements. Quantitative metallography and mechanical testing, both tensile and microhardness, were used for materials assessment at the different steps of the process of manufacturing 6063 anodized extrusions. The results of this research show that nonequilibrium solidification rates during billet casting could lead to the formation of coarse eutectic Mg2Si particles which have a deleterious effect on both mechanical properties and surface appearance in the anodized condition. However, differences in the size and density of the coarse Mg2Si particles have been found to exist in the streak profile compared to the surrounding zones. The study revealed the importance of these particles in explaining the origin of the marginal or sub-marginal properties and anodizing surface defects found. PMID:28788673

Effect of Processing Steps on the Mechanical Properties and Surface Appearance of 6063 Aluminium Extruded Products

Directory of Open Access Journals (Sweden)

Juan Asensio-Lozano

2014-05-01

Full Text Available 6063 aluminum anodized extrusions may exhibit a common surface defect known as streaking, characterized by the formation of narrow bands with a surface gloss different from the surrounding material. The origin of this banding lies in the differential surface topography produced after etching during the anodizing stage, shown to be connected to certain microstructural characteristics. The present study has attempted to determine the origin of these defects and measure the mechanical properties in these zones, properties which were either barely acceptable or did not meet the specification’s requirements. Quantitative metallography and mechanical testing, both tensile and microhardness, were used for materials assessment at the different steps of the process of manufacturing 6063 anodized extrusions. The results of this research show that nonequilibrium solidification rates during billet casting could lead to the formation of coarse eutectic Mg2Si particles which have a deleterious effect on both mechanical properties and surface appearance in the anodized condition. However, differences in the size and density of the coarse Mg2Si particles have been found to exist in the streak profile compared to the surrounding zones. The study revealed the importance of these particles in explaining the origin of the marginal or sub-marginal properties and anodizing surface defects found.

Basic instinct undressed: early spatiotemporal processing for primary sexual characteristics.

Directory of Open Access Journals (Sweden)

Lore B Legrand

Full Text Available This study investigates the spatiotemporal dynamics associated with conscious and non-conscious processing of naked and dressed human bodies. To this effect, stimuli of naked men and women with visible primary sexual characteristics, as well as dressed bodies, were presented to 20 heterosexual male and female participants while acquiring high resolution EEG data. The stimuli were either consciously detectable (supraliminal presentations or were rendered non-conscious through backward masking (subliminal presentations. The N1 event-related potential component was significantly enhanced in participants when they viewed naked compared to dressed bodies under supraliminal viewing conditions. More importantly, naked bodies of the opposite sex produced a significantly greater N1 component compared to dressed bodies during subliminal presentations, when participants were not aware of the stimulus presented. A source localization algorithm computed on the N1 showed that the response for naked bodies in the supraliminal viewing condition was stronger in body processing areas, primary visual areas and additional structures related to emotion processing. By contrast, in the subliminal viewing condition, only visual and body processing areas were found to be activated. These results suggest that naked bodies and primary sexual characteristics are processed early in time (i.e., <200 ms and activate key brain structures even when they are not consciously detected. It appears that, similarly to what has been reported for emotional faces, sexual features benefit from automatic and rapid processing, most likely due to their high relevance for the individual and their importance for the species in terms of reproductive success.

Porous calcium polyphosphate bone substitutes: additive manufacturing versus conventional gravity sinter processing-effect on structure and mechanical properties.

Science.gov (United States)

Hu, Youxin; Shanjani, Yaser; Toyserkani, Ehsan; Grynpas, Marc; Wang, Rizhi; Pilliar, Robert

2014-02-01

Porous calcium polyphosphate (CPP) structures proposed as bone-substitute implants and made by sintering CPP powders to form bending test samples of approximately 35 vol % porosity were machined from preformed blocks made either by additive manufacturing (AM) or conventional gravity sintering (CS) methods and the structure and mechanical characteristics of samples so made were compared. AM-made samples displayed higher bending strengths (≈1.2-1.4 times greater than CS-made samples), whereas elastic constant (i.e., effective elastic modulus of the porous structures) that is determined by material elastic modulus and structural geometry of the samples was ≈1.9-2.3 times greater for AM-made samples. X-ray diffraction analysis showed that samples made by either method displayed the same crystal structure forming β-CPP after sinter annealing. The material elastic modulus, E, determined using nanoindentation tests also showed the same value for both sample types (i.e., E ≈ 64 GPa). Examination of the porous structures indicated that significantly larger sinter necks resulted in the AM-made samples which presumably resulted in the higher mechanical properties. The development of mechanical properties was attributed to the different sinter anneal procedures required to make 35 vol % porous samples by the two methods. A primary objective of the present study, in addition to reporting on bending strength and sample stiffness (elastic constant) characteristics, was to determine why the two processes resulted in the observed mechanical property differences for samples of equivalent volume percentage of porosity. An understanding of the fundamental reason(s) for the observed effect is considered important for developing improved processes for preparation of porous CPP implants as bone substitutes for use in high load-bearing skeletal sites. Copyright © 2013 Wiley Periodicals, Inc.

Characterization and properties of batch-processed melt-textured YBCO

Energy Technology Data Exchange (ETDEWEB)

Kaiser, A.W.; Adam, M.; Bornemann, H.J. [INFP, Forschungszentrum Karlsruhe GmbH, PO Box 3640, 76021 Karlsruhe (Germany)

1998-01-01

High-temperature superconductor bulk parts are batch processed using a semi-automated processing technique based on the melt-texturation process. Levitation properties under static and dynamic load levels were analysed using a test bench with a three-dimensional force sensor unit. Measurements of levitation force give no detailed suggestions on texture, secondary domains or cracks. Therefore other measurements to control homogeneity of the bulk were performed. Texture on full-size pellets (FWHM < 5 deg., {delta}{sub {chi}} < 3 deg.) was verified by elastic neutron scattering. To study the influence of local texture on properties a pellet was divided into nine segments. Preliminary results indicate that a correlation between neutron data and levitation force needs further investigations. Flux maps of samples magnetized by permanent magnets or by a pulsed magnetization unit were used to verify the homogeneity and domain structure of the material and to evaluate macroscopic critical currents. (author)

Relationship between process parameters and properties of multifunctional needlepunched geotextiles

CSIR Research Space (South Africa)

Rawal, A

2006-04-01

Full Text Available , and filtration. In this study, the effect of process parameters, namely, feed rate, stroke frequency, and depth of needle penetration has been investigated on various properties of needlepunched geotextiles. These process parameters are then empirically related...

Wear Process Analysis of the Polytetrafluoroethylene/Kevlar Twill Fabric Based on the Components’ Distribution Characteristics

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Gu Dapeng

2017-12-01

Full Text Available Polytetrafluoroethylene (PTFE/Kevlar fabric or fabric composites with excellent tribological properties have been considered as important materials used in bearings and bushing, for years. The components’ (PTFE, Kevlar, and the gap between PTFE and Kevlar distribution of the PTFE/Kevlar fabric is uneven due to the textile structure controlling the wear process and behavior. The components’ area ratio on the worn surface varying with the wear depth was analyzed not only by the wear experiment, but also by the theoretical calculations with our previous wear geometry model. The wear process and behavior of the PTFE/Kevlar twill fabric were investigated under dry sliding conditions against AISI 1045 steel by using a ring-on-plate tribometer. The morphologies of the worn surface were observed by the confocal laser scanning microscopy (CLSM. The wear process of the PTFE/Kevlar twill fabric was divided into five layers according to the distribution characteristics of Kevlar. It showed that the friction coefficients and wear rates changed with the wear depth, the order of the antiwear performance of the previous three layers was Layer III>Layer II>Layer I due to the area ratio variation of PTFE and Kevlar with the wear depth.

Sintering Process and Mechanical Property of MWCNTs/HDPE Bulk Composite.

Science.gov (United States)

Ming-Wen, Wang; Tze-Chi, Hsu; Jie-Ren, Zheng

2009-08-01

Studies have proved that increasing polymer matrices by carbon nanotubes to form structural reinforcement and electrical conductivity have significantly improved mechanical and electrical properties at very low carbon nanotubes loading. In other words, increasing polymer matrices by carbon nanotubes to form structural reinforcement can reduce friction coefficient and enhance anti-wear property. However, producing traditional MWCNTs in polymeric materix is an extremely complicated process. Using melt-mixing process or in situ polymerization leads to better dispersion effect on composite materials. In this study, therefore, to simplify MWCNTs /HDPE composite process and increase dispersion, powder was used directly to replace pellet to mix and sinter with MWCNTs. The composite bulks with 0, 0.5, 1, 2 and 4% nanotube content by weight was analyzed under SEM to observe nanotubes dispersion. At this rate, a MWCNTs/HDPE composite bulk with uniformly dispersed MWCNTs was achieved, and through the wear bench (Pin-on-Disk), the wear experiment has accomplished. Accordingly, the result suggests the sintered MWCNTs/HDPE composites amplify the hardness and wear-resist property.

Characteristics of the Dendrite Growth in the Electrochemical Alane Production Process

Directory of Open Access Journals (Sweden)

Park Hyun-Kyu

2016-01-01

Full Text Available The electrochemical alane production process was proposed for a feasible production of alane. The operation of process was difficult because of short circuit by a dendrite growth in the reactor. Therefore, characteristics of the dendrite growth in the process were investigated. We conducted the electrochemical alane production process using Teflon block for inhibition of the dendrite growth. The obtained dendrite was characterized by XRD, SEM and ICP-AES. It was concluded that the dendrite growth was attributed to a melting and agglomeration of Al fine particles existed in the solution.

Geometry characteristics modeling and process optimization in coaxial laser inside wire cladding

Science.gov (United States)

Shi, Jianjun; Zhu, Ping; Fu, Geyan; Shi, Shihong

2018-05-01

Coaxial laser inside wire cladding method is very promising as it has a very high efficiency and a consistent interaction between the laser and wire. In this paper, the energy and mass conservation law, and the regression algorithm are used together for establishing the mathematical models to study the relationship between the layer geometry characteristics (width, height and cross section area) and process parameters (laser power, scanning velocity and wire feeding speed). At the selected parameter ranges, the predicted values from the models are compared with the experimental measured results, and there is minor error existing, but they reflect the same regularity. From the models, it is seen the width of the cladding layer is proportional to both the laser power and wire feeding speed, while it firstly increases and then decreases with the increasing of the scanning velocity. The height of the cladding layer is proportional to the scanning velocity and feeding speed and inversely proportional to the laser power. The cross section area increases with the increasing of feeding speed and decreasing of scanning velocity. By using the mathematical models, the geometry characteristics of the cladding layer can be predicted by the known process parameters. Conversely, the process parameters can be calculated by the targeted geometry characteristics. The models are also suitable for multi-layer forming process. By using the optimized process parameters calculated from the models, a 45 mm-high thin-wall part is formed with smooth side surfaces.

Effect of estrogen on tendon collagen synthesis, tendon structural characteristics, and biomechanical properties in postmenopausal women

DEFF Research Database (Denmark)

Hansen, Mette; Kongsgaard, Mads; Holm, Lars

2009-01-01

and fibril characteristics were determined by MRI and transmission electron microscopy, whereas tendon biomechanical properties were measured during isometric maximal voluntary contraction by ultrasound recording. Tendon FSR was markedly higher in ERT-users (P

Identification of physical properties for the retrieval data quality objective process

International Nuclear Information System (INIS)

Gates, C.M.; Beckette, M.R.

1995-06-01

This activity supports the retrieval data quality objective (DQO) process by identifying the material properties that are important to the design, development, and operation of retrieval equipment; the activity also provides justification for characterizing those properties. These properties, which control tank waste behavior during retrieval operations, are also critical to the development of valid physical simulants for designing retrieval equipment. The waste is to be retrieved in a series of four steps. First, a selected retrieval technology breaks up or dislodges the waste into subsequently smaller pieces. Then, the dislodged waste is conveyed out of the tank through the conveyance line. Next, the waste flows into a separator unit that separates the gaseous phase from the liquid and solid phases. Finally, a unit may be present to condition the slurried waste before transporting it to the treatment facility. This document describes the characterization needs for the proposed processes to accomplish waste retrieval. Baseline mobilization technologies include mixer pump technology, sluicing, and high-pressure water-jet cutting. Other processes that are discussed in this document include slurry formation, pneumatic conveyance, and slurry transport. Section 2.0 gives a background of the DQO process and the different retrieval technologies. Section 3.0 provides the mechanistic descriptions and material properties critical to the different technologies and processes. Supplemental information on specific technologies and processes is provided in the appendices. Appendix A contains a preliminary sluicing model, and Appendices B and C cover pneumatic transport and slurry transport, respectively, as prepared for this document. Appendix D contains sample calculations for various equations

Diminishing Chromium Use on Combined Chromium-Gambier Tanning Process Upon the Characteristics of Tanned Leather

Directory of Open Access Journals (Sweden)

A. Kasim

2014-04-01

Full Text Available The research was aimed to investigate the influence of minimizing chromium use on combined chromium-gambier process upon the characteristics of tanned leather. At the first stage of tanning process, chromium was used and in the second stage it was replaced by gambier. The raw material used was dried saline-preserved goat skin. The treatments applied on the tanning process were the different concentrations of chromium ranging from the highest level of 6% to the lowest level of 1% which was then re-tanned by using 8% concentration of gambier. The examination parameters included chemical and physical properties as well as visual investigation on the tanned leather in accordance with SNI-06-0463-1989-A. The result showed that the tanning process by using 2% chromium in the first step and 8% gambier in the second step was a treatment combination producing tanned leather that met the standard. The examination on tanned leather resulted from such treatment showed 56.33% rawhide, 17.45% of bound tannin, 31.22% of tanning level, tensile strength 386.30 kg/cm2, flexibility 31.91%, leather width 1.3 mm, density 0.75 g/cm3, the leather was quite elastic with light brownish color. In conclusion, minimizing the use of chromium in the combined tanning process of chromium and gambier can be implemented to the lowest of 2% chromium concentration and 8% gambier in the first and second step, respectively.

Effect of Particle Acceleration Process on the Flare Characteristics of ...

Indian Academy of Sciences (India)

R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

J. Astrophys. Astr. (2002) 23, 95–99. Effect of Particle Acceleration Process on the Flare Characteristics of. Blazars. S. Bhattacharyya, S. Sahayanathan & C. L. Kaul Nuclear Research Laboratory,. Bhabha Atomic Research Centre, Mumbai 400 085, India. Abstract. Following the kinetic equation approach, we study the flare.

A study on properties of PLA/PBAT from blown film process

International Nuclear Information System (INIS)

Hongdilokkul, P; Keeratipinit, K; Chawthai, S; Suttiruengwong, S; Hararak, B; Seadan, M

2015-01-01

The aim of this work was to study the properties of films based on PLA/PBAT blend prepared by the reactive compounding. PLA/PBAT blends were prepared at the weight ratio of 80:20 together with peroxide as a reactive agent in a twin screw extruder with temperature profile of 160/170/180/210/220/190/175/150°C from feed to die zone. All blended samples, neat PLA, and neat PBAT were characterized for morphology, mechanical and rheological properties. SEM micrographs showed finely dispersed phases of PBAT in PLA in all cases. The particle sizes of PBAT were around 1 μm. The results indicated that the drawability and toughness properties of PLA were greatly improved when blended with 20%wt PBAT. The interface adhesion, and mechanical properties of PLA/PBAT blends were also improved when adding a very small quantity of peroxide. PLA/PBAT blends were then used to produce films. The film characteristics and mechanical properties were examined. Tensile strength of films was significantly improved in the machine direction in PLA/PBAT/peroxide blends whereas the good optical transparent property were remained the same compared with neat PLA. (paper)

Rheological Properties of Extreme Pressure Greases Measured Using a Process Control Rheometer

DEFF Research Database (Denmark)

Glasscock, Julie; Smith, Robin S.

2012-01-01

A new process control rheometer (PCR) designed for use in industrial process flows has been used to measure the rheological properties of three extreme-pressure greases. The rheometer is a robust yet sensitive instrument designed to operate in an industrial processing environment in either in......-line or on-line configurations. The PCR was able to measure the rheological properties including the elastic modulus, viscous modulus, and complex viscosity of the greases which in an industrial flow application could be used as variables in a feedback system to control the process and the quality...

Stationary stochastic processes theory and applications

CERN Document Server

Lindgren, Georg

2012-01-01

Some Probability and Process BackgroundSample space, sample function, and observablesRandom variables and stochastic processesStationary processes and fieldsGaussian processesFour historical landmarksSample Function PropertiesQuadratic mean propertiesSample function continuityDerivatives, tangents, and other characteristicsStochastic integrationAn ergodic resultExercisesSpectral RepresentationsComplex-valued stochastic processesBochner's theorem and the spectral distributionSpectral representation of a stationary processGaussian processesStationary counting processesExercisesLinear Filters - General PropertiesLinear time invariant filtersLinear filters and differential equationsWhite noise in linear systemsLong range dependence, non-integrable spectra, and unstable systemsThe ARMA-familyLinear Filters - Special TopicsThe Hilbert transform and the envelopeThe sampling theoremKarhunen-Loève expansionClassical Ergodic Theory and MixingThe basic ergodic theorem in L2Stationarity and transformationsThe ergodic th...

Effect of thermal processing practices on the properties of superplastic Al-Li alloys

Science.gov (United States)

Hales, Stephen J.; Lippard, Henry E.

1993-01-01

The effect of thermal processing on the mechanical properties of superplastically formed structural components fabricated from three aluminum-lithium alloys was evaluated. The starting materials consisted of 8090, 2090, and X2095 (Weldalite(TM) 049), in the form of commercial-grade superplastic sheet. The experimental test matrix was designed to assess the impact on mechanical properties of eliminating solution heat treatment and/or cold water quenching from post-forming thermal processing. The extensive hardness and tensile property data compiled are presented as a function of aging temperature, superplastic strain and temper/quench rate for each alloy. The tensile properties of the materials following superplastic forming in two T5-type tempers are compared with the baseline T6 temper. The implications for simplifying thermal processing without degradation in properties are discussed on the basis of the results.

Effects of pattern characteristics on the copper electroplating process

International Nuclear Information System (INIS)

Ruan Wenbiao; Chen Lan; Li Zhigang; Ye Tianchun; Ma Tianyu; Wang Qiang

2011-01-01

The non-planarity of a surface post electroplating process is usually dependent on variations of key layout characteristics including line width, line spacing and metal density. A test chip is designed and manufactured in a semiconductor foundry to test the layout dependency of the electroplating process. By checking test data such as field height, array height, step height and SEM photos, some conclusions are made. Line width is a critical factor of topographical shapes such as the step height and height difference. After the electroplating process, the fine line has a thicker copper thickness, while the wide line has the greatest step height. Three typical topographies, conformal-fill, supper-fill and over-fill, are observed. Moreover, quantified effects are found using the test data and explained by theory, which can be used to develop electroplating process modeling and design for manufacturability (DFM) research. (semiconductor integrated circuits)

Naturally Compatible: Starch Acetate/Cellulosic Fiber Composites. I. Processing and Properties

DEFF Research Database (Denmark)

Nättinen, Kalle; Hyvärinen, Sari; Joffe, Roberts

2010-01-01

Composite compounds based on hemp and flax fibers in triethyl citrate plasticized starch acetate were prepared by melt processing. For better properties and processability, compounds with plasticizer contents in the range 20-35 wt% were screened. Composites were prepared with fiber contents up...... to 50 wt%. The composite mechanical properties were measured from injection molded test specimens. A Young's modulus of 8.3 GPa and stress at maximum load of 51 MPa were obtained with 40 wt% flax fiber in a plasticized starch acetate with 20 wt% triethyl citrate. Decreasing the plasticizer...... and increasing the fiber content, the tensile properties were consistently improved. An almost linear relation between fiber content and the tensile properties was found. The increase of the fiber content first improved the impact strength, but at higher fiber contents resulted in a reduction of impact strength...

41 CFR 102-37.50 - What is the general process for requesting surplus property for donation?

Science.gov (United States)

2010-07-01

... process for requesting surplus property for donation? 102-37.50 Section 102-37.50 Public Contracts and... REGULATION PERSONAL PROPERTY 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.50 What is the general process for requesting surplus property for donation? The process for...

Stimulus Characteristics Affect Humor Processing in Individuals with Asperger Syndrome

Science.gov (United States)

Samson, Andrea C.; Hegenloh, Michael

2010-01-01

The present paper aims to investigate whether individuals with Asperger syndrome (AS) show global humor processing deficits or whether humor comprehension and appreciation depends on stimulus characteristics. Non-verbal visual puns, semantic and Theory of Mind cartoons were rated on comprehension, funniness and the punchlines were explained. AS…

Radiation processing and functional properties of soybean (Glycine max)

International Nuclear Information System (INIS)

Pednekar, Mrinal; Das, Amit K.; Rajalakshmi, V; Sharma, Arun

2010-01-01

Effect of radiation processing (10, 20 and 30 kGy) on soybean for better utilization was studied. Radiation processing reduced the cooking time of soybean and increased the oil absorption capacity of soy flour without affecting its proximate composition. Irradiation improved the functional properties like solubility, emulsification activity and foam stability of soybean protein isolate. The value addition effect of radiation processing has been discussed for the products (soy milk, tofu and tofu fortified patties) prepared from soybean.

Electrochemical properties in a seawater environment of 5456-H116 aluminum alloy subjected to optimal friction stir processing

International Nuclear Information System (INIS)

Park, Jae-Cheul; Kim, Seong-Jong

2010-01-01

The mechanical properties of aluminum alloy may be enhanced by modifying the microstructure of the metal by friction stir processing (FSP). Previous studies have demonstrated that the mechanical characteristics of 5456-H116 Al alloy subjected to FSP, at 250 rpm and 15 mm min -1 using a full screw probe, are similar to those of the original alloy. In the present work, the same alloy was processed under these optimal conditions, and the range of favorable protection potentials with regard to hydrogen embrittlement and stress corrosion cracking was determined to lie between -1.3 and -0.7 V (versus Ag/AgCl). The electrochemical behavior of the specimens subjected to FSP was superior to that of the original 5456-H116 Al alloy.

Electrochemical properties in a seawater environment of 5456-H116 aluminum alloy subjected to optimal friction stir processing

Science.gov (United States)

Park, Jae-Cheul; Kim, Seong-Jong

2010-05-01

The mechanical properties of aluminum alloy may be enhanced by modifying the microstructure of the metal by friction stir processing (FSP). Previous studies have demonstrated that the mechanical characteristics of 5456-H116 Al alloy subjected to FSP, at 250 rpm and 15 mm min-1 using a full screw probe, are similar to those of the original alloy. In the present work, the same alloy was processed under these optimal conditions, and the range of favorable protection potentials with regard to hydrogen embrittlement and stress corrosion cracking was determined to lie between -1.3 and -0.7 V (versus Ag/AgCl). The electrochemical behavior of the specimens subjected to FSP was superior to that of the original 5456-H116 Al alloy.

Production process of a new cellulosic fiber with antimicrobial properties.

Science.gov (United States)

Zikeli, Stefan

2006-01-01

The Lyocell process (system: cellulose-water-N-methylmorpholine oxide) of Zimmer AG offers special advantages for the production of cellulose fibers. The process excels by dissolving the most diverse cellulose types as these are optimally adjusted to the process by applying different pretreatment methods. Based on this stable process, Zimmer AG's objective is to impart to the Lyocell fiber additional value to improve quality of life and thus to tap new markets for the product. Thanks to the specific incorporation of seaweed, the process allows to produce cellulose Lyocell fibers with additional and new features. They are activated in a further step - by specific charging with metal ions - in order to obtain antibacterial properties. The favorable textile properties of fibers produced by the Lyocell process are not adversely affected by the incorporation of seaweed material or by activation to obtain an antibacterial fiber so that current textile products can be made from the fibers thus produced. The antibacterial effect is achieved by metal ion activation of the Lyocell fibers with incorporated seaweed, which contrasts with the antibacterial fibers known so far. Antibacterial fibers produced by conventional methods are in part only surface finished with antibacterially active chemicals or else they are produced by incorporating organic substances with antibacterial and fungicidal effects. Being made from cellulose, the antibacterial Lyocell fiber Sea Cell Active as the basis for quality textiles exhibits a special wear comfort compared to synthetic fibers with antibacterial properties and effects. This justifies the conclusion that the Zimmer Lyocell process provides genuine value added and that it is a springboard for further applications.

Effects of gamma irradiation on the protein characteristics and functional properties of sesame (Sesamum indicum L.) seeds

Science.gov (United States)

Hassan, Amro B.; Mahmoud, Nagat S.; Elmamoun, Khalid; Adiamo, Oladipupo Q.; Mohamed Ahmed, Isam A.

2018-03-01

This study was aimed at investigating the effect of gamma irradiation at various doses (0.5, 1.0, 1.5 and 2.0 kGy) on protein characteristics and functional properties of sesame seeds. Gamma radiation at high doses (>1.0 kGy) significantly (P ≤ 0.05) increased globulin and albumin fractions of sesame protein. Concomitant (P ≤ 0.05) increase of in-vitro protein digestibility was noticed in irradiated sesame flour compared to non-radiated sample. Maximum protein solubility was observed in sesame flour irradiated at 1.0 kGy. SDS-PAGE electrophoretic patterns of total sesame protein were not affected by irradiation process. Significant enhancement (P ≤ 0.05) in emulsification capacity (EC) and emulsion stability (ES) was recorded after irradiation at a dose level of 1.0 and 1.5-2.0 kGy, respectively. Foaming capacity reached a significantly maximum value in sesame flour irradiated at 1.0 kGy while foaming stability was not significantly affected by gamma irradiation. It can be concluded that gamma radiation enhances the protein and functional properties of sesame flour and thus can be employed as an effective method of preserving sesame flour and its products.

Property Integration - A New Approach for Simultaneous Solution of Process and Molecular Design Problems

DEFF Research Database (Denmark)

The objective of this paper is to introduce the new concept of property integration. It is based on tracking and integrating properties throughout the process. This is made possible by exploiting the unique features at the interface of process and molecular design. Recently developed clustering...... concepts are employed to identify optimal properties without commitment to specific species. Subsequently, group contribution methods and molecular design techniques are employed to solve the reverse property prediction problem to design molecules possessing the optimal properties....

The Dependence of Characteristic Times of Gradual SEP Events on Their Associated CME Properties

Science.gov (United States)

Pan, Z. H.; Wang, C. B.; Xue, X. H.; Wang, Y. M.

It is generally believed that coronal mass ejections CMEs are the drivers of shocks that accelerate gradual solar energetic particles SEPs One might expect that the characteristics of the SEP intensity time profiles observed at 1 AU are determined by properties of the associated CMEs such as the radial speed and the angular width Recently Kahler statistically investigated the characteristic times of gradual SEP events observed from 1998-2002 and their associated coronal mass ejection properties Astrophys J 628 1014--1022 2005 Three characteristic times of gradual SEP events are determined as functions of solar source longitude 1 T 0 the time from associated CME launch to SEP onset at 1 AU 2 T R the rise time from SEP onset to the time when the SEP intensity is a factor of 2 below peak intensity and 3 T D the duration over which the SEP intensity is within a factor of 2 of the peak intensity However in his study the CME speeds and angular widths are directly taken from the LASCO CME catalog In this study we analyze the radial speeds and the angular widths of CMEs by an ice-cream cone model and re-investigate their correlationships with the characteristic times of the corresponding SEP events We find T R and T D are significantly correlated with radial speed for SEP events in the best-connected longitude range and there is no correlation between T 0 and CME radial speed and angular width which is consistent with Kahler s results On the other hand it s found that T R and T D are also have

Click chemistry approach to conventional vegetable tanning process: accelerated method with improved organoleptic properties.

Science.gov (United States)

Krishnamoorthy, Ganesan; Ramamurthy, Govindaswamy; Sadulla, Sayeed; Sastry, Thotapalli Parvathaleswara; Mandal, Asit Baran

2014-09-01

Click chemistry approaches are tailored to generate molecular building blocks quickly and reliably by joining small units together selectively and covalently, stably and irreversibly. The vegetable tannins such as hydrolyzable and condensed tannins are capable to produce rather stable radicals or inhibit the progress of radicals and are prone to oxidations such as photo and auto-oxidation, and their anti-oxidant nature is well known. A lot remains to be done to understand the extent of the variation of leather stability, color variation (lightening and darkening reaction of leather), and poor resistance to water uptake for prolonged periods. In the present study, we have reported click chemistry approaches to accelerated vegetable tanning processes based on periodates catalyzed formation of oxidized hydrolysable and condensed tannins for high exhaustion with improved properties. The distribution of oxidized vegetable tannin, the thermal stability such as shrinkage temperature (T s) and denaturation temperature (T d), resistance to collagenolytic activities, and organoleptic properties of tanned leather as well as the evaluations of eco-friendly characteristics were investigated. Scanning electron microscopic analysis indicates the cross section of tightness of the leather. Differential scanning calorimetric analysis shows that the T d of leather is more than that of vegetable tanned or equal to aldehyde tanned one. The leathers exhibited fullness, softness, good color, and general appearance when compared to non-oxidized vegetable tannin. The developed process benefits from significant reduction in total solids and better biodegradability in the effluent, compared to non-oxidized vegetable tannins.

Far-Infrared Emission Characteristics and Wear Comfort Property of ZrC-Imbedded Heat Storage Knitted Fabrics for Emotional Garments

Directory of Open Access Journals (Sweden)

Kim Hyun Ah

2017-06-01

Full Text Available This study examined the far-infrared emission characteristics and wear comfort properties of ZrC-imbedded heat storage knitted fabrics. For this purpose, ZrC-imbedded, heat storage PET (polyethylene terephthalate was spun from high-viscosity PET with imbedded ZrC powder on the core part and low-viscosity PET on the sheath part using a conjugated spinning method. ZrC-imbedded PET knitted fabric was also prepared and its physical properties were measured and compared with those of regular PET knitted fabric. In addition, ingredient analysis and the far-infrared emission characteristics of the ZrC-imbedded knitted fabrics were analyzed by energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy. The thermal properties, moisture absorption, and drying properties of the ZrC-imbedded PET knitted fabric were measured and compared with those of the regular PET knitted fabric. The mechanical properties using the FAST (fabric assurance by simple testing system and the dye affinity of the ZrC-imbedded knitted fabric were also measured and compared with those of regular PET knitted fabric.

Influence of nanomechanical crystal properties on the comminution process of particulate solids in spiral jet mills.

Science.gov (United States)

Zügner, Sascha; Marquardt, Karin; Zimmermann, Ingfried

2006-02-01

Elastic-plastic properties of single crystals are supposed to influence the size reduction process of bulk materials during jet milling. According to Pahl [M.H. Pahl, Zerkleinerungstechnik 2. Auflage. Fachbuchverlag, Leipzig (1993)] and H. Rumpf: [Prinzipien der Prallzerkleinerung und ihre Anwendung bei der Strahlmahlung. Chem. Ing. Tech., 3(1960) 129-135.] fracture toughness, maximum strain or work of fracture for example are strongly dependent on mechanical parameters like hardness (H) and young's modulus of elasticity (E). In addition the dwell time of particles in a spiral jet mill proved to correlate with the hardness of the feed material [F. Rief: Ph. D. Thesis, University of Würzburg (2001)]. Therefore 'near-surface' properties have a direct influence on the effectiveness of the comminution process. The mean particle diameter as well as the size distribution of the ground product may vary significantly with the nanomechanical response of the material. Thus accurate measurement of crystals' hardness and modulus is essential to determine the ideal operational micronisation conditions of the spiral jet mill. The recently developed nanoindentation technique is applied to examine subsurface properties of pharmaceutical bulk materials, namely calcite, sodium ascorbate, lactose and sodium chloride. Pressing a small sized tip into the material while continuously recording load and displacement, characteristic diagrams are derived. The mathematical evaluation of the force-displacement-data allows for calculation of the hardness and the elastic modulus of the investigated material at penetration depths between 50-300 nm. Grinding experiments performed with a modified spiral jet mill (Type Fryma JMRS 80) indicate the strong impact of the elastic-plastic properties of a given substance on its breaking behaviour. The fineness of milled products produced at constant grinding conditions but with different crystalline powders varies significantly as it is dependent on the

Computational Flow Dynamic Simulation of Micro Flow Field Characteristics Drainage Device Used in the Process of Oil-Water Separation

Directory of Open Access Journals (Sweden)

Guangya Jin

2017-01-01

Full Text Available Aqueous crude oil often contains large amounts of produced water and heavy sediment, which seriously threats the safety of crude oil storage and transportation. Therefore, the proper design of crude oil tank drainage device is prerequisite for efficient purification of aqueous crude oil. In this work, the composition and physicochemical properties of crude oil samples were tested under the actual conditions encountered. Based on these data, an appropriate crude oil tank drainage device was developed using the principle of floating ball and multiphase flow. In addition, the flow field characteristics in the device were simulated and the contours and streamtraces of velocity magnitude at different nine moments were obtained. Meanwhile, the improvement of flow field characteristics after the addition of grids in crude oil tank drainage device was validated. These findings provide insights into the development of effective selection methods and serve as important references for oil-water separation process.

Direct and mediated impacts of product and process characteristics on consumers’ choice of organic vs. conventional chicken

DEFF Research Database (Denmark)

Marian, Livia; Thøgersen, John

2012-01-01

There is a lack of research into why consumers value process characteristics. In this study, we test the hypothesis that the impact of process characteristics such as organic and free-range on consumers’ choices of food products is at least partly mediated through expected eating quality or taste...... are important for consumers, not only in and off themselves, but partly because consumers make inferences about eating quality from knowledge about such process characteristics....

Effects of Powder Attributes and Laser Powder Bed Fusion (L-PBF) Process Conditions on the Densification and Mechanical Properties of 17-4 PH Stainless Steel

Science.gov (United States)

Irrinki, Harish; Dexter, Michael; Barmore, Brenton; Enneti, Ravi; Pasebani, Somayeh; Badwe, Sunil; Stitzel, Jason; Malhotra, Rajiv; Atre, Sundar V.

2016-03-01

The effects of powders attributes (shape and size distribution) and critical processing conditions (energy density) on the densification and mechanical properties of laser powder bed fusion (L-PBF) 17-4 PH stainless steel were studied using four types of powders. The % theoretical density, ultimate tensile strength and hardness of both water- and gas-atomized powders increased with increased energy density. Gas-atomized powders showed superior densification and mechanical properties when processed at low energy densities. However, the % theoretical density and mechanical properties of water-atomized powders were comparable to gas-atomized powders when sintered at a high energy density of 104 J/mm3. An important result of this study was that, even at high % theoretical density (97% ± 1%), the properties of as-printed parts could vary over a relatively large range (UTS: 500-1100 MPa; hardness: 25-39 HRC; elongation: 10-25%) depending on powder characteristics and process conditions. The results also demonstrate the feasibility of using relatively inexpensive water-atomized powders as starting raw material instead of the typically used gas-atomized powders to fabricate parts using L-PBF techniques by sintering at high energy densities.

Membrane processing technology in the food industry: food processing, wastewater treatment, and effects on physical, microbiological, organoleptic, and nutritional properties of foods.

Science.gov (United States)

Kotsanopoulos, Konstantinos V; Arvanitoyannis, Ioannis S

2015-01-01

Membrane processing technology (MPT) is increasingly used nowadays in a wide range of applications (demineralization, desalination, stabilization, separation, deacidification, reduction of microbial load, purification, etc.) in food industries. The most frequently applied techniques are electrodialysis (ED), reverse osmosis (RO), nanofiltration (NF), ultrafiltration (UF), and microfiltration (MF). Several membrane characteristics, such as pore size, flow properties, and the applied hydraulic pressure mainly determine membranes' potential uses. In this review paper the basic membrane techniques, their potential applications in a large number of fields and products towards the food industry, the main advantages and disadvantages of these methods, fouling phenomena as well as their effects on the organoleptic, qualitative, and nutritional value of foods are synoptically described. Some representative examples of traditional and modern membrane applications both in tabular and figural form are also provided.

Steel Processing Properties and Their Effect on Impact Deformation of Lightweight Structures

Energy Technology Data Exchange (ETDEWEB)

Simunovic, S

2003-09-23

The objective of the research was to perform a comprehensive computational analysis of the effects of material and process modeling approaches on performance of UltraLight Steel Auto Body (ULSAB) vehicle models. The research addressed numerous material related effects, impact conditions as well as analyzed the performance of the ULSAB vehicles in crashes against designs representing the current US vehicle fleet. This report is organized into three main sections. The first section describes the results of the computational analysis of ULSAB crash simulations that were performed using advanced material modeling techniques. The effects of strain-rate sensitivity on a high strength steel (HSS) intensive vehicle were analyzed. Frontal and frontal offset crash scenarios were used in a finite element parametric study of the ULSAB body structure. Comparisons are made between the crash results using the piece-wise-linear isotropic plasticity strain-rate dependent material model, and the isotropic plasticity material model based on quasi-static properties. The simulation results show the importance of advanced material modeling techniques for vehicle crash simulations due to strain-rate sensitivity and rapid hardening characteristics of advanced high strength steels. Material substitution was investigated for the main frontal crush structure using the material of similar yield stress a significantly different strain-rate and hardening characteristics. The objective of the research presented in Section 2 was to assess the influence of stamping process on crash response of ULSAB vehicle. Considered forming effects included thickness variations and plastic strain hardening imparted in the part forming process. The as-formed thickness and plastic strain for front crash parts were used as input data for vehicle crash analysis. Differences in structural performance between crash models with and without forming data were analyzed in order to determine the effects and feasibility of

The NBS: Processing/Microstructure/Property Relationships in 2024 Aluminum Alloy Plates

Science.gov (United States)

Ives, L. K.; Swartzendruber, W. J.; Boettinger, W. J.; Rosen, M.; Ridder, S. D.

1983-01-01

As received plates of 2024 aluminum alloy were examined. Topics covered include: solidification segregation studies; microsegregation and macrosegregation in laboratory and commercially cast ingots; C-curves and nondestructive evaluation; time-temperature precipitation diagrams and the relationships between mechanical properties and NDE measurements; transmission electron microscopy studies; the relationship between microstructure and properties; ultrasonic characterization; eddy-current conductivity characterization; the study of aging process by means of dynamic eddy current measurements; and Heat flow-property predictions, property degradations due to improve quench from the solution heat treatment temperature.

Acquisition of material properties in production for sheet metal forming processes

International Nuclear Information System (INIS)

Heingärtner, Jörg; Hora, Pavel; Neumann, Anja; Hortig, Dirk; Rencki, Yasar

2013-01-01

In past work a measurement system for the in-line acquisition of material properties was developed at IVP. This system is based on the non-destructive eddy-current principle. Using this system, a 100% control of material properties of the processed material is possible. The system can be used for ferromagnetic materials like standard steels as well as paramagnetic materials like Aluminum and stainless steel. Used as an in-line measurement system, it can be configured as a stand-alone system to control material properties and sort out inapplicable material or as part of a control system of the forming process. In both cases, the acquired data can be used as input data for numerical simulations, e.g. stochastic simulations based on real world data

Effects of processing variables on the sensitometric properties of Eastman Kodak film type 2445

Science.gov (United States)

Weinstein, M. S.

1972-01-01

The sensitometric characteristics of Kodak color negative film Type 2445 with processing in a 1411 versamat with Kodak aero-neg. color process chemicals are described. These characteristics were determined for various combinations of machine speed, prehardener temperature, and first developer temperature.

Basic Characteristics of IEC Flickermeter Processing

Directory of Open Access Journals (Sweden)

Jarosław Majchrzak

2012-01-01

. This paper presents the results of the numerical simulations that reconstruct the processing of flickermeter in frequency domain. With the use of standard test signals, the characteristics of flickermeter were determined for the case of amplitude modulation of input signal, frequency modulation of input signal, and for input signal with interharmonic component. For the needs of simulative research, elements of standard IEC flickermeter signal chain as well as test signal source and tools for acquisition, archiving, and presentation of the obtained results were modeled. The results were presented with a set of charts, and the specific fragments of the charts were pointed out and commented on. Some examples of the influence of input signal’s bandwidth limitation on the flickermeter measurement result were presented for the case of AM and FM modulation. In addition, the diagrams that enable the evaluation of flickermeter’s linearity were also presented.

Induced Current Characteristics Due to Laser Induced Plasma and Its Application to Laser Processing Monitoring

International Nuclear Information System (INIS)

Madjid, Syahrun Nur; Idris, Nasrullah; Kurniawan, Koo Hendrik; Kagawa, Kiichiro

2011-01-01

In laser processing, suitable conditions for laser and gas play important role in ensuring a high quality of processing. To determine suitable conditions, we employed the electromagnetic phenomena associated with laser plasma generation. An electrode circuit was utilised to detect induced current due to the fast electrons propelled from the material during laser material processing. The characteristics of induced current were examined by changing parameters such as supplied voltage, laser pulse energy, number of laser shots, and type of ambient gas. These characteristics were compared with the optical emission characteristics. It was shown that the induced current technique proposed in this study is much more sensitive than the optical method in monitoring laser processing, that is to determine the precise focusing condition, and to accurately determine the moment of completion of laser beam penetration. In this study it was also shown that the induced current technique induced by CW CO 2 laser can be applied in industrial material processing for monitoring the penetration completion in a stainless steel plate drilling process.

Impacts of radiation processing on physicochemical properties of Table Eggs

International Nuclear Information System (INIS)

Farag, M. D. H.; Abdul Azeem, A. M.

2012-12-01

This study investigated the effect of gamma irradiation on pathogens, quality, and functional properties of shell eggs. Using intact, fresh while and brown shell eggs, inoculated with 10 9 colony-forming units (cfu) of S enteritidis and S, typhimurium. The effect of gamma-irradiation at doses 2,4 and 6 kGy of gamma irradiation on bacteriologic and population and physical characteristics (Haugh units and yolk color), chemical composition (moisture, crude protein, crude fat and ash), the rheological changes (viscosity), pH and protean solubility of the eggs were determinate d. Results showed that 2 kGy, the number of S, enteritidis and eggs internal quality as freshness as measured by albumen height and the number of hugh units, and yolk color index were all significantly reduced with increasing irradiation doses. On significant change was found after irradiation in egg white or yolk in the chemical composition (moisture, crude protein, crude fat and ash). After irradiation, the foaming ability and foam capacity of egg white were increasing radiation doses> The viscosity of egg white and yolk decreased with increasing doses of irradiation. The pH of the egg white and yolk increasing doses of radiation dose. The protein salability decreased significantly in egg white and yolk with increasing radiation dose. These Results Suggest that gamma irradiation reduce the freshness of shell eggs and improving important functional properties such as to foaming ability and foaming capacity. Gamma irradiation can also be applied to the egg breaking process sine irradiation reduces the viscosity of egg white and yolk, which can allow egg whites and yolks to be separated with greater efficiency. (Author)

Development of Property Models with Uncertainty Estimate for Process Design under Uncertainty

DEFF Research Database (Denmark)

Hukkerikar, Amol; Sarup, Bent; Abildskov, Jens

more reliable predictions with a new and improved set of model parameters for GC (group contribution) based and CI (atom connectivity index) based models and to quantify the uncertainties in the estimated property values from a process design point-of-view. This includes: (i) parameter estimation using....... The comparison of model prediction uncertainties with reported range of measurement uncertainties is presented for the properties with related available data. The application of the developed methodology to quantify the effect of these uncertainties on the design of different unit operations (distillation column......, the developed methodology can be used to quantify the sensitivity of process design to uncertainties in property estimates; obtain rationally the risk/safety factors in process design; and identify additional experimentation needs in order to reduce most critical uncertainties....

Engineering materials properties and process technologies for electronic and energy applications

Science.gov (United States)

Hailey, Anna Kathryn

In this thesis, we pushed the boundaries of knowledge toward exciting new alternatives in the fields of electronic materials and energy. In Part 1, we focused on organic semiconductors, assessing how disorder on different length scales impacts the electrical properties in organic thin-film transistors (OTFTs). We first explored the effect of disorder at the molecular scale due to the coexistence of isomers in thin films. By blending fractional quantities of syn and anti isomers of triethylsilylethynyl anthradithiophene (TES ADT), we found that the electrical properties of devices comprising the anti isomer plummet to that of syn after the addition of only 10% syn. Through single-crystal computational analysis, we determined that the addition of syn disorders the two-dimensional electronic coupling between anti molecules, thereby increasing charge trapping and decreasing mobilities in OTFTs with increasing syn concentrations in the active layers. We also elucidated the impact of disorder stemming from boundaries between crystalline superstructures in polycrystalline thin films. By measuring the electrical characteristics of OTFTs across interspherulite boundaries (ISBs) in TES ADT and rubrene thin films, we found the energy barriers for charge transport across ISBs to be more akin to those found across the boundaries between polymer crystallites than between conventional molecular-semiconductor grains. In contrast to sharp, creviced grain boundaries, ISBs presumably comprise trapped molecules that electrically connect neighboring spherulites, as polymer chains connect crystallites in polymer-semiconductor thin films. In Part 2, we turned our focus to the production of alternative liquid fuels, evaluating process designs to produce "drop-in" replacement diesel and gasoline from non-food biomass and domestic natural gas. By considering the storage of captured byproduct CO2 in nearby depleted shale-gas wells, these processes produce liquid fuels with low

Effect of different drying techniques on flowability characteristics and chemical properties of natural carbohydrate-protein Gum from durian fruit seed

Directory of Open Access Journals (Sweden)

Mirhosseini Hamed

2013-01-01

Full Text Available Abstract Background A natural carbohydrate biopolymer was extracted from the agricultural biomass waste (durian seed. Subsequently, the crude biopolymer was purified by using the saturated barium hydroxide to minimize the impurities. Finally, the effect of different drying techniques on the flow characteristics and functional properties of the purified biopolymer was investigated. The present study elucidated the main functional characteristics such as flow characteristics, water- and oil-holding capacity, solubility, and foaming capacity. Results In most cases except for oven drying, the bulk density decreased, thus increasing the porosity. This might be attributed to the increase in the inter-particle voids of smaller sized particles with larger contact surface areas per unit volume. The current study revealed that oven-dried gum and freeze-dried gum had the highest and lowest compressibility index, thus indicating the weakest and strongest flowability among all samples. In the present work, the freeze-dried gum showed the lowest angle of repose, bulk, tapped and true density. This indicates the highest porosity degree of freeze dried gum among dried seed gums. It also exhibited the highest solubility, and foaming capacity thus providing the most desirable functional properties and flow characteristics among all drying techniques. Conclusion The present study revealed that freeze drying among all drying techniques provided the most desirable functional properties and flow characteristics for durian seed gum.

Effect of biometric characteristics on biomechanical properties of the cornea in cataract patient

Directory of Open Access Journals (Sweden)

Xue-Fei Song

2016-06-01

Full Text Available AIM: To determine the impact of biometric characteristics on the biomechanical properties of the human cornea using the ocular response analyzer (ORA and standard comprehensive ophthalmic examinations before and after standard phacoemulsification. METHODS: This study comprised 54 eyes with cataract with significant lens opacification in stages I or II that underwent phacoemulsification (2.8 mm incision. Corneal hysteresis (CH, corneal resistance factor (CRF, Goldmann-correlated intraocular pressure (IOPg, and corneal-compensated intraocular pressure (IOPcc were measured by ORA preoperatively and at 1mo postoperatively. Biometric characteristics were derived from corneal topography [TMS-5, anterior equivalent (EQTMS and cylindric (CYLTMS power], corneal tomography [Casia, anterior and posterior equivalent (EQaCASIC, EQpCASIA and cylindric (CYLaCASIA, CYLpCASIA power], keratometry [IOLMaster, anterior equivalent (EQIOL and cylindric (CYLIOL power] and autorefractor [anterior equivalent (EQAR]. Results from ORA were analyzed and correlated with those from all other examinations taken at the same time point. RESULTS: Preoperatively, CH correlated with EQpCASIA and CYLpCASIA only (P=0.001, P=0.002. Postoperatively, IOPg and IOPcc correlated with all equivalent powers (EQTMS, EQIOL, EQAR, EQaCASIA and EQpCASIA (P=0.001, P=0.007, P=0.001, P=0.015, P=0.03 for IOPg and P<0.001, P=0.003, P<0.001, P=0.009, P=0.014 for IOPcc. CH correlated postoperatively with EQaCASIA and EQpCASIC only (P=0.021, P=0.022. CONCLUSION: Biometric characteristics may significantly affect biomechanical properties of the cornea in terms of CH, IOPcc and IOPg before, but even more after cataract surgery.

STRUCTURAL CHARACTERISTICS & DIELECTRIC PROPERTIES OF TANTALUM OXIDE DOPED BARIUM TITANATE BASED MATERIALS

Directory of Open Access Journals (Sweden)

Md. Fakhrul Islam

2013-01-01

Full Text Available In this research, the causal relationship between the dielectric properties and the structural characteristics of 0.5 & 1.0 mole % Ta2O5 doped BaTiO3 based ceramic materials were investigated under different sintering conditions. Dielectric properties and microstructure of BaTio3 ceramics were significantly influenced by the addition of a small amount of Ta2O5. Dielectric properties were investigated by measuring the dielectric constant (k as a function of temperature and frequency. Percent theoretical density (%TD above 90 % was achieved for 0.5 and 1.0 mole %Ta2O5 doped BaTiO3. It was observed that the grain size decreased markedly above a doping concentration of 0.5 mole % Ta2O5. Although fine grain size down to 200 - 300 nm was attained, grain sizes in the range of 1-1.8µm showed the most alluring properties. The fine-grain quality and high density of the Ta2O5 doped BaTiO3 ceramic resulted in tenfold increase of dielectric constant. Stable value of dielectric constant as high as 13000 - 14000 was found in the temperature range of 55 to 80 °C, for 1.0 mole % Ta2O5 doped samples with corresponding shift of Curie point to ~82 °C. Experiments divulged that incorporation of a proper content of Ta2O5 in BaTiO3 could control the grain growth, shift the Curie temperature and hence significantly improve the dielectric property of the BaTiO3 ceramics.

Study on infrasonic characteristics of coal samples in failure process under uniaxial loading

Directory of Open Access Journals (Sweden)

Bing Jia

Full Text Available To study the precursory failure infrasonic characteristics of coal samples, coal rock stress loading system and infrasonic wave acquisition system were adopted, and infrasonic tests in uniaxial loading process were made for the coal samples in the studied area. Wavelet filtering, fast Fourier transform, and relative infrasonic energy methods were used to analyze the characteristics of the infrasonic waves in the loading process, including time domain characteristics, and relative energy. The analysis results demonstrated that the frequencies of the infrasonic signals in the loading process mainly distribute within 5–10 Hz, which are significantly different from noise signals. The changes of the infrasonic signals show clear periodic characters in time domain. Meanwhile, the relative energy changes of the infrasonic wave also show periodic characters, which are divided into two stages by the yield limit of coal samples, and are clear and easy to be recognized, so that they can be used as the precursory characteristics for recognizing coal sample failures. Moreover, the infrasonic waves generated by coal samples have low frequency and low attenuation, which can be collected without coupling and transmitted in long distance. This study provides an important support for the further in-situ prediction of coal rock failures. Keywords: Infrasound, Relative energy, Time-frequency analysis, Failure prediction, Identification feature

Effect of processing method on surface and weathering characteristics of wood-flour/HDPE composites

Science.gov (United States)

Nicole M. Stark; Laurent M. Matuana; Craig M. Clemons

2004-01-01

Wood-plastic lumber is promoted as a low maintenance high-durability product. When exposed to accelerated weathering, however, wood-plastic composites may experience a color change and/or loss in mechanical properties. Different methods of manufacturing wood-plastic composites lead to different surface characteristics, which can influence weathering, In this study, 50...

On the Processing and Properties of Clay/Polymer Nanocomposites CPNC

Directory of Open Access Journals (Sweden)

Refat El-Sheikhy

Full Text Available AbstractAn experimental investigation followed by fundamental characterization and discussion on the effect of nanoclay filler on the mechanical and fracture properties of polymer matrix was carried out. The study was carried out on clay/polymer nanocomposite made of High Density polyethylene (HDPE M40060 produced by Saudi Arabian company SABIC and montimorillonite MMT nanoclay (Nanomer I.34TCN produced by Nanocore, USA. MMT nanomer I.34TCN is surface modified with organic surfactant to facilitate the bonding between nanoclay and HDPE. Current clay/polymer nanocomposite CPNC was produced by special technique of mixing, processing and molding. Samples of nanoclay, HDPE and nanocomposite were characterized by XRD, SEM and EDAX for investigating the chistillanity, distribution, desperion, intercalation, exfoliation, homogenity and defects. These aspects govern CPNC processing and bond between nanoclay and HDPE which controls the mechanical and fracture properties. Sheets of the produced CPNC were prepared for mechanical and fracture testing. Mechanical properties such as tensile strength, yield stress and elongation were tested and compared for both of pure HDPE and CPNC using non standard test specimens of flat sheets for comparison purposes. Fracture mechanics tests for checking and comparing the critical stress intensity factor due to stress concentration at the crack tips for mode I crack (KIc were carried out using precracked non standard flat sheet specimens subjected to uniaxial uniform tensile stresses. Furthermore, standard experimental tests were conducted for both of HDPE and CPNC for investigating standard mechanical properties aspects based on ASTM D 638 using standard dumbbell-shaped specimen while for investigating standard fracture toughness standard single edge notch specimens SENB subjected bending moment due to effect of 3-point load based on ASTM D 5045 were carried out. The results showed that procedures of mixing, processing

Preliminary Evaluation on Characteristics of Waste from Pyro-processing (FS v5.1)

International Nuclear Information System (INIS)

Kim, In-Young; Choi, Heui-Joo

2016-01-01

In this study, characteristic of waste from pyro-processing which based on material balance FS v5.1 is evaluated for revising of A-KRS concept. To reduce volume and toxicity of PWR SNFs, the P and T Technology using pyro-processing and SFR is under development in KAERI. In accordance with this R and D, the A-KRS was developed by KAERI for disposal of waste from pyro-processing. After A-KRS concept development, material balance has been revised and characteristics of waste have been changed. To solve impending saturation of storage capacity of NPP sites, national policy on SNF management seems to be determined shortly. Demand on detailed analysis on impact of P and T using pyro-processing and SFR as base data is increasing. To compare direct disposal scenario to the P and T scenario using pyro-processing and SFR, updating of A-KRS reflecting amendment of material balance is required. In this study, characteristic of waste from pyro-processing which based on material balance FS v5.1 is evaluated. Every 15 types of outputs generated from pyro-processing are evaluated. Great reduction can be achieved by complete reuse of U/TRU/RE in SFR, because most of decay heat, radioactivity and radiotoxicity are generated from U/TRU/RE ingot. Within about 300 years, the fly ash filter containing Cs, Sr containing salt waste are important waste in perspective of decay heat and radioactivity. Importance of RE containing salt waste reduced. Management of hold-ups must be clarified because hold-ups take large portion of decay heat, radioactivity in the material balance FS v5.1

Preliminary Evaluation on Characteristics of Waste from Pyro-processing (FS v5.1)

Energy Technology Data Exchange (ETDEWEB)

Kim, In-Young; Choi, Heui-Joo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

In this study, characteristic of waste from pyro-processing which based on material balance FS v5.1 is evaluated for revising of A-KRS concept. To reduce volume and toxicity of PWR SNFs, the P and T Technology using pyro-processing and SFR is under development in KAERI. In accordance with this R and D, the A-KRS was developed by KAERI for disposal of waste from pyro-processing. After A-KRS concept development, material balance has been revised and characteristics of waste have been changed. To solve impending saturation of storage capacity of NPP sites, national policy on SNF management seems to be determined shortly. Demand on detailed analysis on impact of P and T using pyro-processing and SFR as base data is increasing. To compare direct disposal scenario to the P and T scenario using pyro-processing and SFR, updating of A-KRS reflecting amendment of material balance is required. In this study, characteristic of waste from pyro-processing which based on material balance FS v5.1 is evaluated. Every 15 types of outputs generated from pyro-processing are evaluated. Great reduction can be achieved by complete reuse of U/TRU/RE in SFR, because most of decay heat, radioactivity and radiotoxicity are generated from U/TRU/RE ingot. Within about 300 years, the fly ash filter containing Cs, Sr containing salt waste are important waste in perspective of decay heat and radioactivity. Importance of RE containing salt waste reduced. Management of hold-ups must be clarified because hold-ups take large portion of decay heat, radioactivity in the material balance FS v5.1.

Setting Mechanical Properties of High Strength Steels for Rapid Hot Forming Processes

Science.gov (United States)

Löbbe, Christian; Hering, Oliver; Hiegemann, Lars; Tekkaya, A. Erman

2016-01-01

Hot stamping of sheet metal is an established method for the manufacturing of light weight products with tailored properties. However, the generally-applied continuous roller furnace manifests two crucial disadvantages: the overall process time is long and a local setting of mechanical properties is only feasible through special cooling techniques. Hot forming with rapid heating directly before shaping is a new approach, which not only reduces the thermal intervention in the zones of critical formability and requested properties, but also allows the processing of an advantageous microstructure characterized by less grain growth, additional fractions (e.g., retained austenite), and undissolved carbides. Since the austenitization and homogenization process is strongly dependent on the microstructure constitution, the general applicability for the process relevant parameters is unknown. Thus, different austenitization parameters are analyzed for the conventional high strength steels 22MnB5, Docol 1400M, and DP1000 in respect of the mechanical properties. In order to characterize the resulting microstructure, the light optical and scanning electron microscopy, micro and macro hardness measurements, and the X-ray diffraction are conducted subsequent to tensile tests. The investigation proves not only the feasibility to adjust the strength and ductility flexibly, unique microstructures are also observed and the governing mechanisms are clarified. PMID:28773354

The prion protein has RNA binding and chaperoning properties characteristic of nucleocapsid protein NCP7 of HIV-1.

Science.gov (United States)

Gabus, C; Derrington, E; Leblanc, P; Chnaiderman, J; Dormont, D; Swietnicki, W; Morillas, M; Surewicz, W K; Marc, D; Nandi, P; Darlix, J L

2001-06-01

Transmissible spongiform encephalopathies are fatal neurodegenerative diseases associated with the accumulation of a protease-resistant form of the prion protein (PrP). Although PrP is conserved in vertebrates, its function remains to be identified. In vitro PrP binds large nucleic acids causing the formation of nucleoprotein complexes resembling human immunodeficiency virus type 1 (HIV-1) nucleocapsid-RNA complexes and in vivo MuLV replication accelerates the scrapie infectious process, suggesting possible interactions between retroviruses and PrP. Retroviruses, including HIV-1 encode a major nucleic acid binding protein (NC protein) found within the virus where 2000 NC protein molecules coat the dimeric genome. NC is required in virus assembly and infection to chaperone RNA dimerization and packaging and in proviral DNA synthesis by reverse transcriptase (RT). In HIV-1, 5'-leader RNA/NC interactions appear to control these viral processes. This prompted us to compare and contrast the interactions of human and ovine PrP and HIV-1 NCp7 with HIV-1 5'-leader RNA. Results show that PrP has properties characteristic of NCp7 with respect to viral RNA dimerization and proviral DNA synthesis by RT. The NC-like properties of huPrP map to the N-terminal region of huPrP. Interestingly, PrP localizes in the membrane and cytoplasm of PrP-expressing cells. These findings suggest that PrP is a multifunctional protein possibly participating in nucleic acid metabolism.

Durability Characteristics Analysis of Plastic Worm Wheel with Glass Fiber Reinforced Polyamide.

Science.gov (United States)

Kim, Gun-Hee; Lee, Jeong-Won; Seo, Tae-Il

2013-05-10

Plastic worm wheel is widely used in the vehicle manufacturing field because it is favorable for weight lightening, vibration and noise reduction, as well as corrosion resistance. However, it is very difficult for general plastics to secure the mechanical properties that are required for vehicle gears. If the plastic resin is reinforced by glass fiber in the fabrication process of plastic worm wheel, it is possible to achieve the mechanical properties of metallic material levels. In this study, the mechanical characteristic analysis of the glass-reinforced plastic worm wheel, according to the contents of glass fiber, is performed by analytic and experimental methods. In the case of the glass fiber-reinforced resin, the orientation and contents of glass fibers can influence the mechanical properties. For the characteristic prediction of plastic worm wheel, computer-aided engineering (CAE) analysis processes such as structural and injection molding analysis were executed with the polyamide resin reinforcement glass fiber (25 wt %, 50 wt %). The injection mold for fabricating the prototype plastic worm wheel was designed and made to reflect the CAE analysis results. Finally, the durability of prototype plastic worm wheel fabricated by the injection molding process was evaluated by the experimental method and the characteristics according to the glass fiber contents.

Influence of Fiber Volume Fraction on the Tensile Properties and Dynamic Characteristics of Coconut Fiber Reinforced Composite

OpenAIRE

Izzuddin Zaman; Al Emran Ismail; Muhamad Khairudin Awang

2011-01-01

The utilization of coconut fibers as reinforcement in polymer composites has been increased significantly due to their low cost and high specific mechanical properties. In this paper, the mechanical properties and dynamic characteristics of a proposed combined polymer composite which consist of a polyester matrix and coconut fibers are determined. The influence of fibers volume fraction (%) is also evaluated and composites with volumetric amounts of coconut fiber up to 15% are fabricated. In ...

Model Optimization Identification Method Based on Closed-loop Operation Data and Process Characteristics Parameters

Directory of Open Access Journals (Sweden)

Zhiqiang GENG

2014-01-01

Full Text Available Output noise is strongly related to input in closed-loop control system, which makes model identification of closed-loop difficult, even unidentified in practice. The forward channel model is chosen to isolate disturbance from the output noise to input, and identified by optimization the dynamic characteristics of the process based on closed-loop operation data. The characteristics parameters of the process, such as dead time and time constant, are calculated and estimated based on the PI/PID controller parameters and closed-loop process input/output data. And those characteristics parameters are adopted to define the search space of the optimization identification algorithm. PSO-SQP optimization algorithm is applied to integrate the global search ability of PSO with the local search ability of SQP to identify the model parameters of forward channel. The validity of proposed method has been verified by the simulation. The practicability is checked with the PI/PID controller parameter turning based on identified forward channel model.

Relationship of electrical, magnetic, and mechanical properties to processing in high-temperature superconductors

International Nuclear Information System (INIS)

Blendell, J.E.; Chiang, C.K.; Cranmer, D.C.

1987-01-01

The interrelation between processing, microstructure, and properties is an important factor in understanding the behavior of ceramic materials. This type of understanding will be particularly important in the development of the new high T/sub c/ superconducting ceramic oxides of the type Ba/sub 2/YCu/sub 3/O/sub 7-x/. As an initial effort in understanding these relations, a number of properties have been measured for these superconducting ceramics and related to their microstructure and processing sequence. The Ba/sub 2/YCu/sub 3/O/sub 7-x/ ceramics were prepared by powder processing techniques, followed by dry pressing and sintering in both air and flowing oxygen at various temperatures. The sintered bodies were annealed at various temperatures and environments. Superconducting properties, such as the transition temperature and the width of the transition, were measured by both electrical conductivity and AC magnetic susceptibility; both of these properties show a strong sensitivity to annealing temperature and atmosphere. The microstructure and density were also strongly dependent on processing conditions. In this regard, compositional mapping proved to be an important technique for quantifying microstructural variations. Mechanical properties, such as elastic modulus, hardness, and fracture toughness, which will be important for the reliable use of these materials in large scale structures, were also determined

Process design of press hardening with gradient material property influence

International Nuclear Information System (INIS)

Neugebauer, R.; Schieck, F.; Rautenstrauch, A.

2011-01-01

Press hardening is currently used in the production of automotive structures that require very high strength and controlled deformation during crash tests. Press hardening can achieve significant reductions of sheet thickness at constant strength and is therefore a promising technology for the production of lightweight and energy-efficient automobiles. The manganese-boron steel 22MnB5 have been implemented in sheet press hardening owing to their excellent hot formability, high hardenability, and good temperability even at low cooling rates. However, press-hardened components have shown poor ductility and cracking at relatively small strains. A possible solution to this problem is a selective increase of steel sheet ductility by press hardening process design in areas where the component is required to deform plastically during crash tests. To this end, process designers require information about microstructure and mechanical properties as a function of the wide spectrum of cooling rates and sequences and austenitizing treatment conditions that can be encountered in production environments. In the present work, a Continuous Cooling Transformation (CCT) diagram with corresponding material properties of sheet steel 22MnB5 was determined for a wide spectrum of cooling rates. Heating and cooling programs were conducted in a quenching dilatometer. Motivated by the importance of residual elasticity in crash test performance, this property was measured using a micro-bending test and the results were integrated into the CCT diagrams to complement the hardness testing results. This information is essential for the process design of press hardening of sheet components with gradient material properties.

Damascus steels: history, processing, properties and carbon dating

International Nuclear Information System (INIS)

Wadsworth, J.

2007-01-01

In the mid-1970s, a class of steels containing high levels of carbon (∼ 1-2 wt% C) was developed for superplastic characteristics - that is, the ability to plastically deform to an extraordinary degree in tension at intermediate temperatures. Because these steels also had excellent room temperature properties, they were developed for their commercial potential. In the late 1970s, we became aware of the striking compositional similarities between these modern steels and the ancient steels of Damascus. This observation led us to revisit the history and metallurgy of Damascus steels and related steels. The legends and origins of Damascus steel date back to the time of Alexander the Great (323 BC) and the medieval Crusades (11th and 12th century AD), and this material has also been the subject of scrutiny by famous scientist in Europe, including Michael Faraday. Modern attempts to reproduce the legendary surface patterns which famously characterized Damascus steels are described. The extend to which the characteristics of Damascus steels are unusual is discussed. Finally, a program on radiocarbon dating was initiated to directly determine the age of about 50 ancient steels, including a Damascus knife, and the results are summarized. (author)

Characteristics of high-level radioactive waste forms for their disposal

International Nuclear Information System (INIS)

Kim, Seung Soo; Chun, Kwan Sik; Kang, Chul Hyung

2000-12-01

In order to develop a deep geological repository for a high-level radioactive waste coming from reprocessing of spent nuclear fuels discharged from our domestic nuclear power plants, the the required characteristics of waste form are dependent upon a solidifying medium and the amount of waste loading in the medium. And so, by the comparative analysis of the characteristics of various waste forms developed up to the present, a suitable medium is recommended.The overall characteristics of the latter is much better than those of the former, but the change of the properties due to an amorphysation by radiation exposure and its thermal expansion has not been clearly identified yet. And its process has not been commercialized. However, the overall properties of the borosilicate glass waste forms are acceptable for their disposal, their production cost is reasonable and their processes have already been commercialized. And plenty informations of their characteristics and operational experiences have been accumulated. Consequently, it is recommended that a suitable medium solidifying the HLW is a borosilicate glass and its composition for the identification of a reference waste form would be based on the glass frit of R7T7

Supercapacitive characteristics of electrochemically active porous materials

Directory of Open Access Journals (Sweden)

VLADIMIR V. PANIC

2008-06-01

Full Text Available The results of an investigation of the capacitive characteristics of sol–gel-processed titanium- and carbon-supported electrochemically active noble metal oxides, as representatives of porous electrode materials, are presented in the lecture. The capacitive properties of these materials were correlated to their composition, the preparation conditions of the oxides and coatings, the properties of the carbon support and to the composition of the electrolyte. The results of the electrochemical test methods, cyclic voltammetry and electrochemical impedance spectroscopy, were employed to resolve the possible physical structures of the mentioned porous materials, which are governed by the controlled conditions of the preparation of the oxide by the sol–gel process.

Comparative Study of Laboratory-Scale and Prototypic Production-Scale Fuel Fabrication Processes and Product Characteristics

International Nuclear Information System (INIS)

Marshall, Douglas W.

2014-01-01

An objective of the High Temperature Gas Reactor fuel development and qualification program for the United States Department of Energy has been to qualify fuel fabricated in prototypic production-scale equipment. The quality and characteristics of the tristructural isotropic (TRISO) coatings on fuel kernels are influenced by the equipment scale and processing parameters. The standard deviations of some TRISO layer characteristics were diminished while others have become more significant in the larger processing equipment. The impact on statistical variability of the processes and the products, as equipment was scaled, are discussed. The prototypic production-scale processes produce test fuels meeting all fuel quality specifications. (author)

Probability, random processes, and ergodic properties

CERN Document Server

Gray, Robert M

1988-01-01

This book has been written for several reasons, not all of which are academic. This material was for many years the first half of a book in progress on information and ergodic theory. The intent was and is to provide a reasonably self-contained advanced treatment of measure theory, prob ability theory, and the theory of discrete time random processes with an emphasis on general alphabets and on ergodic and stationary properties of random processes that might be neither ergodic nor stationary. The intended audience was mathematically inc1ined engineering graduate students and visiting scholars who had not had formal courses in measure theoretic probability . Much of the material is familiar stuff for mathematicians, but many of the topics and results have not previously appeared in books. The original project grew too large and the first part contained much that would likely bore mathematicians and dis courage them from the second part. Hence I finally followed the suggestion to separate the material and split...

Research progress of laser welding process dynamic monitoring technology based on plasma characteristics signal

Directory of Open Access Journals (Sweden)

Teng WANG

2017-02-01

Full Text Available During the high-power laser welding process, plasmas are induced by the evaporation of metal under laser radiation, which can affect the coupling of laser energy and the workpiece, and ultimately impact on the reliability of laser welding quality and process directly. The research of laser-induced plasma is a focus in high-power deep penetration welding field, which provides a promising research area for realizing the automation of welding process quality inspection. In recent years, the research of laser welding process dynamic monitoring technology based on plasma characteristics is mainly in two aspects, namely the research of plasma signal detection and the research of laser welding process modeling. The laser-induced plasma in the laser welding is introduced, and the related research of laser welding process dynamic monitoring technology based on plasma characteristics at home and abroad is analyzed. The current problems in the field are summarized, and the future development trend is put forward.

Sensory properties of marinated herring (Clupea harengus) processed from raw material from commercial landings

DEFF Research Database (Denmark)

Nielsen, Durita; Hyldig, Grethe; Nielsen, Jette

2005-01-01

Sensory properties of marinated herring processed from raw material from Danish commercial catches were described and related to fishing season and biological, chemical and functional properties. Herring was caught on five cruises and stored on board in tanks or ice. The sensory profile of marina......Sensory properties of marinated herring processed from raw material from Danish commercial catches were described and related to fishing season and biological, chemical and functional properties. Herring was caught on five cruises and stored on board in tanks or ice. The sensory profile...

Influence of inductive heating on microstructure and material properties in roll forming processes

Science.gov (United States)

Guk, Anna; Kunke, Andreas; Kräusel, Verena; Landgrebe, Dirk

2017-10-01

The increasing demand for sheet metal parts and profiles with enhanced mechanical properties by using high and ultra-high-strength (UHS) steels for the automotive industry must be covered by increasing flexibility of tools and machines. This can be achieved by applying innovative technologies such as roll forming with integrated inductive heating. This process is similar to indirect press hardening and can be used for the production of hardened profiles and profiles with graded properties in longitudinal and traverse direction. The advantage is that the production of hardened components takes place in a continuous process and the integration of heating and quenching units in the profiling system increases flexibility, accompanied by shortening of the entire process chain and minimizing the springback risk. The features of the mentioned process consists of the combination of inhomogeneous strain distribution over the stripe width by roll forming and inhomogeneity of microstructure by accelerated inductive heating to austenitizing temperature. Therefore, these two features have a direct influence on the mechanical properties of the material during forming and hardening. The aim of this work is the investigation of the influence of heating rates on microstructure evolution and mechanical properties to determine the process window. The results showed that heating rate should be set at 110 K/s for economic integration of inductive heating into the roll forming process.

Physical properties, evaporation and combustion characteristics of nanofluid-type fuels

Science.gov (United States)

Tanvir, Saad

Nanofluids are liquids with stable suspension of nanoparticles. Limited studies in the past have shown that both energetic and catalytic nanoparticles once mixed with traditional liquid fuels can be advantageous in combustion applications, e.g., increased energy density and shortened ignition delay. Contradictions in existing literature, scarcity of experimental data and lack of understanding on how the added nanoparticles affect the physical properties as well as combustion characteristics of the resulting fuel motivated us to launch a detailed experimental and theoretical investigation. The surface tension of ethanol and n-decane based nanofluid fuels containing suspended nanoparticles were measured using the pendant drop method by solving the Young-Laplace equation. The results show that surface tension increases both with particle concentration (above a critical concentration) and particle size. This is because the Van der Waals forces between particles at the liquid/gas interface increases surface free energy that overcomes any electrostatic repulsion between the particles and increases surface tension. This present work also reports experimental analysis of the latent heat of vaporization ( Hfg) of nanofluids. Results show that the addition of Ag and Fe nanoparticles in water results is a substantial reduction in Hfg. On the contrary Al addition slightly increases Hfg. Similar observations are made for ethanol based nanofluids. Molecular dynamics simulations showed that the strength of bonding between particles and the fluid molecules is the governing factor in the variation of Hfg upon particle addition. The thermal conductivity was measured using KD2-Pro from Decagon Devices based on the transient line heat source method. The rheological properties of the ethanol and ethanol/nanoparticles suspensions are measured using a StresstechRTM rotational rheometer. Both properties increased with increasing particle concentration. Trends are found to be consistent

Biopolymers to improve physical properties and leaching characteristics of mortar and concrete: A review

Science.gov (United States)

Olivia, M.; Jingga, H.; Toni, N.; Wibisono, G.

2018-04-01

The invention of environmentally friendly, high performance, and green material such as biopolymers marked an emerging trend for sustainable construction over the past decades. Biopolymer comprises of natural monomers and synthesized by plants or other organisms. The sustainable, biodegradable, and renewable biopolymers were used in concrete mixes to improve their physical and mechanical properties and durability. The aim of this paper is to provide a brief an overview of the impact of biopolymer addition into concrete and mortar mixes. Many studies on the influence of biopolymer on the properties of concrete and mortar by adding biopolymers at a certain proportion (usually less than one wt.%) to the concrete or mortar mixes, and the heavy metal leaching, rheological, and mechanical properties of the mixes were conducted. Biopolymers included in this review are chitosan (CH), xanthan gum (XG), guar gum (GG), lignosulphonate (LS), and cellulose ethers (CE). Data from previous studies showed that the addition of certain types of biopolymer into concrete and mortar mixes improve workability, water retention, and compressive strength by up to 30 percent. Chitosan strengthens heavy metal encapsulation in the mortar and neutralizes the negative impact of heavy metal on the mortar properties and environment. To sum up, the use of biopolymers improve physical properties and leaching characteristics of mortar and concrete.

Effect of nanocomposite gate-dielectric properties on pentacene microstructure and field-effect transistor characteristics.

Science.gov (United States)

Lee, Wen-Hsi; Wang, Chun-Chieh

2010-02-01

In this study, the effect of surface energy and roughness of the nanocomposite gate dielectric on pentacene morphology and electrical properties of pentacene OTFT are reported. Nanoparticles TiO2 were added in the polyimide matrix to form a nanocomposite which has a significantly different surface characteristic from polyimide, leading to a discrepancy in the structural properties of pentacene growth. A growth mode of pentacene deposited on the nanocomposite is proposed to explain successfully the effect of surface properties of nanocomposite gate dielectric such as surface energy and roughness on the pentacene morphology and electrical properties of OTFT. To obtain the lower surface energy and smoother surface of nanocomposite gate dielectric that is responsible for the desired crystalline, microstructure of pentacene and electrical properties of device, a bottom contact OTFT-pentacene deposited on the double-layer nanocomposite gate dielectric consisting of top smoothing layer of the neat polyimide and bottom layer of (PI+ nano-TiO2 particles) nanocomposite has been successfully demonstrated to exhibit very promising performance including high current on to off ratio of about 6 x 10(5), threshold voltage of -10 V and moderately high filed mobility of 0.15 cm2V(-1)s(-1).

Structural Characteristics & Dielectric Properties of Tantalum Oxide Doped Barium Titanate Based Materials

Directory of Open Access Journals (Sweden)

Rubayyat Mahbub

2012-11-01

Full Text Available In this research, the causal relationship between the dielectric properties and the structural characteristics of 0.5 & 1.0 mol% Ta2O5 doped BaTiO3 based ceramic materials were investigated under different sintering conditions. Dielectric properties and microstructure of BaTio3 ceramics were significantly influenced by the addition of a small amount of Ta2O5. Dielectric properties were investigated by measuring the dielectric constant (k as a function of temperature and frequency. Percent theoretical density (%TD above 90% was achieved for 0.5 and 1.0 mol% Ta2O5 doped BaTiO3. It was observed that the grain size decreased markedly above a doping concentration of 0·5 mol% Ta2O5. Although fine grain size down to 200-300nm was attained, grain sizes in the range of 1-1.8µm showed the most alluring properties. The fine-grain quality and high density of the Ta2O5 doped BaTiO3 ceramic resulted in tenfold increase of dielectric constant. Stable value of dielectric constant as high as 13000-14000 was found in the temperature range of  55 to 80°C, for 1.0 mol% Ta2O5 doped samples with corresponding shift of Curie point to ~82°C. Experiments divulged that incorporation of a proper content of Ta2O5 in BaTiO3 could control the grain growth, shift the Curie temperature and hence significantly improve the dielectric property of the BaTiO3 ceramics.

Structure-Property Relationships in Polycyanurate / Graphene Networks

Science.gov (United States)

2015-12-12

Briefing Charts 3. DATES COVERED (From - To) 17 Nov 2015 – 12 Dec 2015 4. TITLE AND SUBTITLE Structure-Property Relationships in Polycyanurate...ANSI Std. 239.18 1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Structure-Property Relationships in...the attractive processing characteristics of LECy are retained in graphene oxide / LECy mixtures. Impurities, such as aryl phenols and transition metals

Basic characteristics of Sporolactobacillus inulinus BCRC 14647 for potential probiotic properties.

Science.gov (United States)

Huang, Hui-Ying; Huang, Shih-Yi; Chen, Pei-Yu; King, V An-Erl; Lin, Yeu-Pyng; Tsen, Jen-Horng

2007-05-01

The basic characteristics of the spore-forming lactic acid bacterium, Sporolactobacillus inulinus BCRC 14647, was evaluated in vitro for its potential probiotic properties. Assessments including acid and bile salt tolerance, adhesiveness, and antagonistic effects on pathogenic Salmonella enteritidis BCRC 10744, as well as inhibition factors of spent culture supernatant (SCS) and an invasion assay, were conducted using Lactobacillus acidophilus BCRC 10695 and two bifidobacteria (Bifidobacterium bifidum BCRC 14615 and B. longum BCRC 11847) as a reference. In the results, S. inulinus spores presented significantly higher survival rates than the vegetative cell form in acidic conditions as well as the reference bifidobacteria. However, L. acidophilus showed the highest viability among all tested strains. Similar results were found in the bile tolerance test. Compared with the reference strains, the vegetative cell form of S. inulinus possessed a proper adhesive characteristic (71.7 bacteria/field for S. inulinus and 91.3 and 45.7 bacteria/field for B. bifidum and B. longum, respectively). In the adhesion assay, both the spore form of S. inulinus (17.1 bacteria/field) and the negative control, L. bulgaricus BCRC 14009 (5.9 bacteria/field), displayed nonadhesive traits. The vegetative cells of S. inulinus and its SCS both dramatically decrease the adhesion of S. enteritidis to Caco-2 cells; meanwhile, the SCS of S. inulinus vegetative cells inhibited the growth of S. enteritidis in the inhibition zone test. The existing inhibition factor could be assumed to be lactic acid in the SCS. From the results of the invasion assay, S. inulinus showed high safety properties. In conclusion, based on these in vitro evaluations, results suggest that S. inulinus presents probiotic features of great potential in the vegetative cell form.

Dynamic texture perception, oral processing behaviour and bolus properties of emulsion-filled gels with and without contrasting mechanical properties

NARCIS (Netherlands)

Devezeaux de Lavergne, M.S.M.; Tournier, C.; Bertrand, D.; Salles, C.; Velde, van de F.; Stieger, M.A.

2016-01-01

Many highly palatable foods are composed of multiple components which can have considerably different mechanical properties leading to contrasting texture sensations. The aim of this study was to better understand the impact of contrasting mechanical properties in semi-solid gels on oral processing

Processing and properties of silver-metal oxide electrical contact materials

Directory of Open Access Journals (Sweden)

Nadežda M. Talijan

2012-12-01

Full Text Available The presented study gives a brief overview of the experimental results of investigations of different production technologies of silver-metal oxide electrical contact materials in relation: processing method - properties. The two most common routes of production, i.e. internal oxidation/ingot metallurgy and powder metallurgy are demonstrated on the example of Ag-CdO and Ag-ZnO materials. For illustration of alternative processing routes that provide higher dispersion of metal-oxide particles in silver matrix more environmentally friendly Ag-SnO2 contact materials are used. Processing of electrical contact materials by mechanical mixing of starting powders in high energy ball mill is presented. The obtained experimental results of application of different methods of introduction of SnO2 nanoparticles in the silver matrix such as conventional powder metallurgy mixing and template method are given and discussed in terms of their influence on microstructure and physical properties (density, hardness and electrical conductivity of the prepared Ag-SnO2 electrical contact materials.

Estimation of environment-related properties of chemicals for design of sustainable processes: development of group-contribution+ (GC+) property models and uncertainty analysis.

Science.gov (United States)

Hukkerikar, Amol Shivajirao; Kalakul, Sawitree; Sarup, Bent; Young, Douglas M; Sin, Gürkan; Gani, Rafiqul

2012-11-26

of the developed property models for the estimation of environment-related properties and uncertainties of the estimated property values is highlighted through an illustrative example. The developed property models provide reliable estimates of environment-related properties needed to perform process synthesis, design, and analysis of sustainable chemical processes and allow one to evaluate the effect of uncertainties of estimated property values on the calculated performance of processes giving useful insights into quality and reliability of the design of sustainable processes.

Property-process relationships in nuclear fuel fabrication

International Nuclear Information System (INIS)

Tikare, V.

2015-01-01

Nuclear fuels are fabricated using many different techniques as they come in a large variety of shapes and compositions. The design and composition of nuclear fuels are predominantly dictated by the engineering requirements necessary for their function in reactors of various designs. Other engineering properties requirements originate from safety and security concerns, and the easy of handling, storing, transporting and disposing of the radioactive materials. In this chapter, the more common of these fuels will be briefly reviewed and the methods used to fabricate them will be presented. The fuels considered in this paper are oxide fuels used in LWRs and FRs, metal fuels in FRs and particulate fuels used in HTGRs. Fabrication of alternative fuel forms and use of standard fuels in alternative reactors will be discussed briefly. The primary motivation to advance fuel fabrication is to improve performance, reduce cost, reduce waste or enhance safety and security of the fuels. To achieve optimal performance, developing models to advance fuel fabrication has to be done in concert with developing fuel performance models. The specific properties and microstructures necessary for improved fuel performance must be identified using fuel performance models, while fuel fabrication models that can determine processing variables to give the desired microstructure and materials properties must be developed. (author)

Comparison of in vitro cell binding characteristics of four monoclonal antibodies and their individual tumor localization properties in mice

International Nuclear Information System (INIS)

Andrew, S.M.; Johnstone, R.W.; Russell, S.M.; McKenzie, I.F.; Pietersz, G.A.

1990-01-01

Although many antibodies are being used for imaging studies, it is not clear which in vitro properties of antibodies will best reflect their in vivo characteristics. The ability to correlate in vitro binding characteristics of monoclonal antibodies to tumor antigens with their in vivo localization characteristics, particularly with respect to tumor localization properties, is desirable for rapid selection of monoclonal antibodies with potential for clinical use. The in vitro binding characteristics of three monoclonal antibodies to the murine Ly-2.1 antigen and one to the Ly-3.1 antigen have been studied on cultured tumor cells bearing these antigens. The association and dissociation rate constants, apparent affinity, and immunoreactivity of each antibody in vitro were compared with their ability to localize the s.c. tumors from the same cell line growing in Ly-2.1-/Ly-3.1-mice. The antibody with the highest affinity and fastest association rate localized to tumor at the earliest time (16-20 h after injection) and had the highest percentage of the injected dose/g in the tumor (greater than 25%). The antibody with the lowest affinity showed significantly less localization to tumor cells, compared with the other three antibodies. The ranking of the antibodies by affinity agreed with the ranking in terms of their ability to localize to tumors, but the in vitro immunoreactivity of the antibodies, as measured by a cell binding assay, did not correlate with their tumor localization properties. Immunoscintigraphic studies did not precisely correlate with biodistribution data or in vitro binding characteristics, because tumors could be satisfactorily imaged with each antibody, although it was noted that the antibody with the highest affinity gave the best image

Microstructures and mechanical properties of Ti5553 alloy processed by high-pressure torsion

Science.gov (United States)

Jiang, B. Z.; Emura, S.; Tsuchiya, K.

2014-08-01

In the present research, the effects of high-pressure torsion (HPT) processing on the microstructure and mechanical properties of Ti-5Al-5Mo-5V-3Cr (Ti5553) alloy were studied. HPT processing produced a white etching layer (WEL) in the middle section of the cross-section and numerous shear bands in the surface region of the cross-section. And the thickness of the WEL increased with increasing the HPT revolutions. TEM observation of the WEL revealed an ultrafine-grained structure with high degree of lattice distortions. The mechanical properties measurements showed that the hardness and ultimate tensile strength increased by HPT processing, accompanied with a decrease in the elongation to failure. It is considered that the mechanical properties of HPT processed Ti5553 alloy are mostly dominated by the shear banded region and the WEL where have the finest grain size and high density of dislocations.

Microstructures and mechanical properties of Ti5553 alloy processed by high-pressure torsion

International Nuclear Information System (INIS)

Jiang, B Z; Emura, S; Tsuchiya, K

2014-01-01

In the present research, the effects of high-pressure torsion (HPT) processing on the microstructure and mechanical properties of Ti-5Al-5Mo-5V-3Cr (Ti5553) alloy were studied. HPT processing produced a white etching layer (WEL) in the middle section of the cross-section and numerous shear bands in the surface region of the cross-section. And the thickness of the WEL increased with increasing the HPT revolutions. TEM observation of the WEL revealed an ultrafine-grained structure with high degree of lattice distortions. The mechanical properties measurements showed that the hardness and ultimate tensile strength increased by HPT processing, accompanied with a decrease in the elongation to failure. It is considered that the mechanical properties of HPT processed Ti5553 alloy are mostly dominated by the shear banded region and the WEL where have the finest grain size and high density of dislocations

Mineralogical characteristics of the silica polymorphs in relation to their biological activities

Energy Technology Data Exchange (ETDEWEB)

Guthrie, G.D. Jr. [Los Alamos National Lab., NM (United States); Heaney, P.J. [Princeton Univ., NJ (United States). Dept. of Geological and Geophysical Sciences

1993-10-01

Numerous aspects of minerals (including the silica polymorphs) can effect their biological activities. These include periodic structures, compositional variations, dissolution characteristics, surface properties, and particle size/shape. In order to understand mineral-induced pathogenesis in a mechanistic way, the links between these properties and biochemical processes must be elucidated. This paper presents some of the basic properties of the silica polymorphs that may relate to pathogenicity and mineralogical strategies for designing biological assays to evaluate these properties.

Dielectric properties of Zea mays kernels - studies for microwave power processing applications

Energy Technology Data Exchange (ETDEWEB)

Surducan, Emanoil; Neamtu, Camelia; Surducan, Vasile, E-mail: emanoil.surducan@itim-cj.r [National Institute for Research and Development of Isotopic and Molecular Technologies, 65-103 Donath, 400293 Cluj-Napoca (Romania)

2009-08-01

Microwaves absorption in biological samples can be predicted by their specific dielectrical properties. In this paper, the dielectric properties ({epsilon}' and {epsilon}'') of corn (Zea mays) kernels in the 500 MHz - 20 GHz frequencies range are presented. A short analysis of the microwaves absorption process is also presented, in correlation with the specific thermal properties of the samples, measured by simultaneous TGA-DSC method.

Effect of Sn doping on structural, mechanical, optical and electrical properties of ZnO nanoarrays prepared by sol-gel and hydrothermal process

Science.gov (United States)

Agarwal, Manish Baboo; Sharma, Akash; Malaidurai, M.; Thangavel, R.

2018-05-01

Undoped and Sn doped Zinc oxide nanorods were prepared by two step process: initially growth of seed layers by sol-gel spin coating technique and then zinc oxide nanorods by hydrothermal process using the precursors zinc nitrate hexahydrate, hexamine and tin chloride. The effects on the electrical, optical, mechanical and structural properties for various Sn concentrations were studied. The crystalline phase determination from X-ray diffraction (XRD) confirms that Sn doped ZnO nanorods have hexagonal wurtzite structure. The variations of stress and strain with different doping concentration of Sn in ZnO nanorods were studied. The doping effect on electrical properties and optical bandgap is estimated by current voltage characteristics and absorbance spectra respectively. The surface morphology was studied with field emission scanning electron microscope (FESEM), which shows that the formation of hexagonal nanorods arrays with increasing Sn concentration. The calculated value of Young's modulus of elasticity (Y) for all the samples remains same. These results can be used in optoelectronic devices.

A research on the mechanical property, work efficiency and structural characteristics of heavyweight concrete

International Nuclear Information System (INIS)

Ishimura, Kikuo; Ooue, Minoru; Noda, Shizuo; Suzuki, Keiichi; Ishii, Takakazu; Nakazawa, Kouichi; Mitsugi, Shiro.

1991-01-01

Generally thickness is increased in walls and slabs to improve the shielding ability of normal concrete in the buildings in nuclear power plants. On the other hand, the decrease of thickness of members and the decrease of building size can be expected by the adoption of heavy weight concrete. But there are little principal members such as shear walls using heavy weight concrete. Therefore, the data related to the mechanical properties and the construction method are not sufficient. This study was carried out to examine the properties and the structural characteristics of heavy weight concrete, and to establish the construction method. The selection of aggregate, the properties of aggregate and the properties of heavy weight concrete are reported. Pumping test was carried out with two kinds of the mixing proportion, and its procedure and the results are shown. The heavy weight concrete was placed as wall specimens, and its procedure and the results are described. The static loading test on shear wall specimens was carried out, and its procedure and the results are reported. Magnetite and hematite ores adopted as the aggregate caused no problem. (K.I.)

Microstructure characteristics of nickel reinforced metal matrix composites (Ni/AC8A) by low-pressure metal infiltration process

Energy Technology Data Exchange (ETDEWEB)

Lee, Hyun Jun; Rong, Hua Wei; Jun, Ji Ang; Park, Sung Ho; Huh, Sun Chul; Park, Won Jo [Gyeongsang National University, Jinju (Korea, Republic of)

2009-07-01

MMCs(Metal Matrix Composites) can obtain mechanical characteristics of application purposes that a single material is difficult to obtain. Al alloy composite material that nickel is added by reinforcement is used for piston of diesel engine, because high temperature properties, strength, corrosion resistant are improved excellently than existent Al alloy. And, in case of processing, interface between Ni and Al improves wear resistant by intermetallic compound of high hardness. Also, in the world, industrial circles are proceeding research to apply excellent composite material. Existent process methods of MMC using preform were manufactured by high-pressure. But, it cause deformation of preform or fault of completed MMC. Using low-pressure as infiltration pressure can prevent this problem, and there is an advantage that is able to reduce the cost of production by small scale of production equipment. Accordingly, process methods of MMC have to consider low-pressure infiltration for the strength of preform, and nowadays, there are many studies about reducing infiltration pressure. In this study produced Al composite material that Ni is added by reinforcement by low-pressure infiltration, and observed microstructure of completed MMCs.

CMOS and BiCMOS process integration and device characterization

CERN Document Server

El-Kareh, Badih

2009-01-01

Covers both the theoretical and practical aspects of modern silicon devices and the relationship between their electrical properties and processing conditions. This book also covers silicon devices and integrated process technologies. It discusses modern silicon devices, their characteristics, and interactions with process parameters.

Lipid technology: Property prediction and process design/analysis in the edible oil and biodiesel industries

DEFF Research Database (Denmark)

Díaz Tovar, Carlos Axel; Gani, Rafiqul; Sarup, Bent

2011-01-01

acid methyl esters); their representation and classification in terms of molecular structures; the collection of available experimental data of their pure component physical properties; the adoption of appropriate property-process models for the design and analysis of production processes through......In this work some of the property related issues in lipid processing technology employed in edible oil and biodiesel production are highlighted. This includes the identification of the most representative chemical species (acylglycerides, free fatty acids, tocopherols, sterols, carotenes, and fatty...

Enhanced electrical properties in solution-processed InGaZnO thin-film transistors by viable hydroxyl group transfer process

Science.gov (United States)

Kim, Do-Kyung; Jeong, Hyeon-Seok; Kwon, Hyeok Bin; Kim, Young-Rae; Kang, Shin-Won; Bae, Jin-Hyuk

2018-05-01

We propose a simple hydroxyl group transfer method to improve the electrical characteristics of solution-processed amorphous InGaZnO (IGZO) thin-film transistors (TFTs). Tuned poly(dimethylsiloxane) elastomer, which has a hydroxyl group as a terminal chemical group, was adhered temporarily to an IGZO thin-film during the solidification step to transfer and supply sufficient hydroxyl groups to the IGZO thin-film. The transferred hydroxyl groups led to efficient hydrolysis and condensation reactions, resulting in a denser metal–oxygen–metal network being achieved in the IGZO thin-film compared to the conventional IGZO thin-film. In addition, it was confirmed that there was no morphological deformation, including to the film thickness and surface roughness. The hydroxyl group transferred IGZO based TFTs exhibited enhanced electrical properties (field-effect mobility of 2.21 cm2 V‑1 s‑1, and on/off current ratio of 106) compared to conventional IGZO TFTs (field-effect mobility of 0.73 cm2 V‑1 s‑1 and on/off current ratio of 105).

The Electrochemical Properties of Biochars and How They Affect Soil Redox Properties and Processes

Directory of Open Access Journals (Sweden)

Stephen Joseph

2015-07-01

Full Text Available Biochars are complex heterogeneous materials that consist of mineral phases, amorphous C, graphitic C, and labile organic molecules, many of which can be either electron donors or acceptors when placed in soil. Biochar is a reductant, but its electrical and electrochemical properties are a function of both the temperature of production and the concentration and composition of the various redox active mineral and organic phases present. When biochars are added to soils, they interact with plant roots and root hairs, micro-organisms, soil organic matter, proteins and the nutrient-rich water to form complex organo-mineral-biochar complexes Redox reactions can play an important role in the development of these complexes, and can also result in significant changes in the original C matrix. This paper reviews the redox processes that take place in soil and how they may be affected by the addition of biochar. It reviews the available literature on the redox properties of different biochars. It also reviews how biochar redox properties have been measured and presents new methods and data for determining redox properties of fresh biochars and for biochar/soil systems.

Rheological and mechanical properties of polyamide 6 modified by electron-beam initiated mediation process

International Nuclear Information System (INIS)

Shin, Boo Young; Kim, Jae Hong

2015-01-01

Polyamide (PA6) has been modified by electron-beam initiated mediator process to improve drawbacks of PA6. Glycidyl methacrylate (GMA) was chosen as a reactive mediator for modification process of PA6. The mixture of the PA6 and GMA was prepared by using a twin-screw extruder, and then the mixture was exposed to electron-beam irradiation at various doses at room temperature. The modified PA6 were characterized by observing rheological and mechanical properties and compared virgin PA6. Thermal properties, water absorption, and gel fraction were also investigated. Tight gel was not found even when PA6 was irradiated at 200 kGy. Complex viscosity and storage modulus of PA6 were remarkably increased by electron-beam irradiation with medium of GMA. Maximum increase in complex viscosity was 75 times higher than virgin PA6 at 0.1 rad/s when it was irradiated at 200 kGy with the GMA. Mechanical properties were also improved without scarifying of processability. The reaction mechanisms for the mediation process with the reactive mediator of GMA were estimated to elucidate the cause of significantly enhanced rheological and mechanical properties without loss of thermoplasticity. - Highlights: • PA6 was modified by the electron-beam initiated mediation process. • Maximum increase in complex viscosity of modified PA6 was 75 times higher than virgin PA6 at 0.1 rad/s. • Mechanical properties were improved without scarifying of processability. • The GMA as a mediator played a key role in the electron-beam initiated mediation process

Estimation of macroscopic elastic characteristics for hierarchical anisotropic solids based on probabilistic approach

Science.gov (United States)

Smolina, Irina Yu.

2015-10-01

Mechanical properties of a cable are of great importance in design and strength calculation of flexible cables. The problem of determination of elastic properties and rigidity characteristics of a cable modeled by anisotropic helical elastic rod is considered. These characteristics are calculated indirectly by means of the parameters received from statistical processing of experimental data. These parameters are considered as random quantities. With taking into account probable nature of these parameters the formulas for estimation of the macroscopic elastic moduli of a cable are obtained. The calculating expressions for macroscopic flexural rigidity, shear rigidity and torsion rigidity using the macroscopic elastic characteristics obtained before are presented. Statistical estimations of the rigidity characteristics of some cable grades are adduced. A comparison with those characteristics received on the basis of deterministic approach is given.

PHYSICALCHEMICAL CHARACTERIZATION AND THERMOPHYSICAL PROPERTIES OF COCOA HONEY

Directory of Open Access Journals (Sweden)

Biano Alves de Melo Neto

2016-03-01

Full Text Available The objective of this study was to determine the physicochemical characteristics and thermophysical properties of cocoa hoeny. The cocoa honey had the following physicalchemical characteristics: pH (2.76, titratable acidity (0.73 %, moisture (87,22 %, soluble solids (14,03 °Brix, reducing sugar (10,2 % in glucose, non-reducing sugar (4,06 % in saccharose and ash (0,23 %. With respect to the thermophysical properties were determined the specific heat, density, thermal diffusivity and the dynamic viscosity as a function of temperature. The empirical models for each property were obtained. It was found that the temperature directly affects the cocoa liquor properties. The data are important for the development, adaptation and optimization of equipment for more efficient processing of cocoa honey, since the information on this subject is unknown.

Characteristics and gelling property of phosphorylated gelatin from the skin of unicorn leatherjacket.

Science.gov (United States)

Kaewruang, Phanngam; Benjakul, Soottawat; Prodpran, Thummanoon

2014-03-01

The characteristics and gelling property of gelatin from the skin of unicorn leatherjacket, phosphorylated with sodium tripolyphosphate (STPP) at various concentrations (0.25%, 0.50%, 0.75% and 1.00% w/w), for different times (1 and 3h) at 65°C, were studied. With the increase of STPP concentration and time, no increase in bound phosphate was observed. The highest gel strength was obtained for gelatin phosphorylated using 0.25% STPP for 1h (Punicorn leatherjacket. Copyright © 2013 Elsevier Ltd. All rights reserved.

A method of network topology optimization design considering application process characteristic

Science.gov (United States)

Wang, Chunlin; Huang, Ning; Bai, Yanan; Zhang, Shuo

2018-03-01

Communication networks are designed to meet the usage requirements of users for various network applications. The current studies of network topology optimization design mainly considered network traffic, which is the result of network application operation, but not a design element of communication networks. A network application is a procedure of the usage of services by users with some demanded performance requirements, and has obvious process characteristic. In this paper, we first propose a method to optimize the design of communication network topology considering the application process characteristic. Taking the minimum network delay as objective, and the cost of network design and network connective reliability as constraints, an optimization model of network topology design is formulated, and the optimal solution of network topology design is searched by Genetic Algorithm (GA). Furthermore, we investigate the influence of network topology parameter on network delay under the background of multiple process-oriented applications, which can guide the generation of initial population and then improve the efficiency of GA. Numerical simulations show the effectiveness and validity of our proposed method. Network topology optimization design considering applications can improve the reliability of applications, and provide guidance for network builders in the early stage of network design, which is of great significance in engineering practices.

Cu(In,Ga)Se{sub 2} absorber thinning and the homo-interface model: Influence of Mo back contact and 3-stage process on device characteristics

Energy Technology Data Exchange (ETDEWEB)

Leonard, E.; Arzel, L.; Tomassini, M.; Barreau, N., E-mail: nicolas.barreau@univ-nantes.fr [Institut des Matériaux Jean Rouxel (IMN)-UMR 6502, Université de Nantes, CNRS, 2 rue de la Houssinière, BP 32229, 44322 Nantes Cedex 3 (France); Zabierowski, P. [Faculty of Physics, Warsaw University of Technology, Koszykowa 75, PL 00-662 Warsaw (Poland); Fuertes Marrón, D. [Instituto de Energía Solar–ETSIT, Technical University of Madrid, Ciudad Universitaria s.n., 28040 Madrid (Spain)

2014-08-21

Thinning the absorber layer is one of the possibilities envisaged to further decrease the production costs of Cu(In,Ga)Se{sub 2} (CIGSe) thin films solar cell technology. In the present study, the electronic transport in submicron CIGSe-based devices has been investigated and compared to that of standard devices. It is observed that when the absorber is around 0.5 μm-thick, tunnelling enhanced interface recombination dominates, which harms cells energy conversion efficiency. It is also shown that by varying either the properties of the Mo back contact or the characteristics of 3-stage growth processing, one can shift the dominating recombination mechanism from interface to space charge region and thereby improve the cells efficiency. Discussions on these experimental facts led to the conclusions that 3-stage process implies the formation of a CIGSe/CIGSe homo-interface, whose location as well as properties rule the device operation; its influence is enhanced in submicron CIGSe based solar cells.

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)

Inverse magnetostrictive characteristics of Fe-Co composite materials using gas-nitriding process

Science.gov (United States)

Nakajima, Kenya; Yang, Zhenjun; Narita, Fumio

2018-03-01

The inverse magnetostrictive response, known as the Villari effect, of magnetostrictive materials is a change in magnetization due to an applied stress. It is commonly used for sensor applications. This work deals with the inverse magnetostrictive characteristics of Fe-Co bimetal plates that were subjected gas-nitriding process. Gas-nitriding was performed on bimetal plates for 30 min at 853 K as a surface heat treatment process. The specimens were cooled to room temperature after completing the nitriding treatment. Three-point bending tests were performed on the plates under a magnetic field. The changes on the magnetic induction of the plates due to the applied load are discussed. The effect of the nitriding treatment on the inverse magnetostrictive characteristics, magnetostrictive susceptibility, and magnetic hysteresis loop was examined. Our work represents an important step forward in the development of magnetostrictive sensor materials.

The differential effects of position, ad and reader characteristics on readers' processing of newspaper ads

NARCIS (Netherlands)

Smit, E.G.; Neijens, P.C.; Heath, R.

2013-01-01

Building on previous research on the processing of newspaper ads, this comprehensive field study, with 26,556 newspaper readers and 290 unique advertisements, investigated the combined effects of position in the newspaper, ad characteristics and reader characteristics. The results show a

Characteristics and properties of cladding tubes for VVER-1000 higher Uranium content fuel rods

International Nuclear Information System (INIS)

Peregud, M.; Markelov, A.; Novikov, V.; Gusev, A.; Konkov, V.; Pimenov, Y.; Agapitov, V.; Shtutsa, M.

2009-01-01

To improve the fuel cycle economics and to further increase the VVER fuel usability the work programme is under way to design novel improved fuel, fuel rods and fuel assemblies. Longer FA operation time that is needed to increase the fuel burnup and the related design developments of novel fuel assemblies resulted not only in changing types and sizes of Zirconium items and fuel assembly components but also altered the requirements placed on their technical characteristics. To use fuel rods having a larger charge of fuel, to improve their behaviour in LOCA, to reduce fuel rod damage ability during assembling the work was carried out to perfect the characteristics of both the cladding (reduced wall thickness and more rigid tolerances for geometry) and its material. To meet the more rigid requirements for the geometry dimensions of cladding tubes an improved process flow sheet has been designed and employed for their fabrication and also the finishing treatment of tube surfaces has been improved. The higher and stable properties of the cladding materials were managed through using the special purity in terms of Hafnium Zirconium (not higher than 100 ppm Hf) as a base of the E110 alloy and maintaining within the valid specifications for the alloy the optimized contents of Oxygen and Iron at the levels of (600 - 990) ppm and (250 - 700) ppm, respectively. The work was under way in 2004 - 2008 years; during this period the technology and materials science solutions were mastered that were phased-in introduced into the production of the cladding tubes for the fuels loaded into the of the Kalinin NPP Unit 1

Effect of Source, Surfactant, and Deposition Process on Electronic Properties of Nanotube Arrays

Directory of Open Access Journals (Sweden)

Dheeraj Jain

2011-01-01

Full Text Available The electronic properties of arrays of carbon nanotubes from several different sources differing in the manufacturing process used with a variety of average properties such as length, diameter, and chirality are studied. We used several common surfactants to disperse each of these nanotubes and then deposited them on Si wafers from their aqueous solutions using dielectrophoresis. Transport measurements were performed to compare and determine the effect of different surfactants, deposition processes, and synthesis processes on nanotubes synthesized using CVD, CoMoCAT, laser ablation, and HiPCO.

Influence of different processing techniques on the mechanical properties of used tires in embankment construction

International Nuclear Information System (INIS)

Edincliler, Ayse; Baykal, Goekhan; Saygili, Altug

2010-01-01

Use of the processed used tires in embankment construction is becoming an accepted way of beneficially recycling scrap tires due to shortages of natural mineral resources and increasing waste disposal costs. Using these used tires in construction requires an awareness of the properties and the limitations associated with their use. The main objective of this paper is to assess the different processing techniques on the mechanical properties of used tires-sand mixtures to improve the engineering properties of the available soil. In the first part, a literature study on the mechanical properties of the processed used tires such as tire shreds, tire chips, tire buffings and their mixtures with sand are summarized. In the second part, large-scale direct shear tests are performed to evaluate shear strength of tire crumb-sand mixtures where information is not readily available in the literature. The test results with tire crumb were compared with the other processed used tire-sand mixtures. Sand-used tire mixtures have higher shear strength than that of the sand alone and the shear strength parameters depend on the processing conditions of used tires. Three factors are found to significantly affect the mechanical properties: normal stress, processing techniques, and the used tire content.

Influence of different processing techniques on the mechanical properties of used tires in embankment construction.

Science.gov (United States)

Edinçliler, Ayşe; Baykal, Gökhan; Saygili, Altug

2010-06-01

Use of the processed used tires in embankment construction is becoming an accepted way of beneficially recycling scrap tires due to shortages of natural mineral resources and increasing waste disposal costs. Using these used tires in construction requires an awareness of the properties and the limitations associated with their use. The main objective of this paper is to assess the different processing techniques on the mechanical properties of used tires-sand mixtures to improve the engineering properties of the available soil. In the first part, a literature study on the mechanical properties of the processed used tires such as tire shreds, tire chips, tire buffings and their mixtures with sand are summarized. In the second part, large-scale direct shear tests are performed to evaluate shear strength of tire crumb-sand mixtures where information is not readily available in the literature. The test results with tire crumb were compared with the other processed used tire-sand mixtures. Sand-used tire mixtures have higher shear strength than that of the sand alone and the shear strength parameters depend on the processing conditions of used tires. Three factors are found to significantly affect the mechanical properties: normal stress, processing techniques, and the used tire content. Copyright 2009. Published by Elsevier Ltd.

Friction and wear characteristics of Al-Cu/C composites synthesized using partial liquid phase casting process

International Nuclear Information System (INIS)

Ng, W.B.; Gupta, M.; Lim, S.C.

1997-01-01

During the sliding of aluminium alloys dispersed with graphite particulates, a layer of graphite is usually present at the sliding interface. This tribo-layer significantly reduces the amount of direct metal-to-metal contact, giving rise to low friction and a low rate of wear, making these composites useful candidate materials for anti-friction applications. Such self-lubricating composites are commonly fabricated via the squeeze casting, slurry casting or powder metallurgy route. These processes are expensive while the less-expensive conventional casting route is limited by the agglomeration of graphite particles in the composites, giving rise to poor mechanical properties. In this work, graphite particulate-reinforced Al-4.5 wt.% Cu composites with two effective graphite contents (Al-4.5 Cu/4.2 wt.% C and Al-4.5 Cu/6.8 wt.% C) were synthesized through an innovative partial liquid phase casting (rheocasting) technique, which is a modification of the conventional casting process. Unlubricated (without the use of conventional liquid lubrication) friction and wear performance of these composites as well as the un-reinforced aluminium alloy was determined using a pin-on-disk tester. The results revealed that the graphite-reinforced composites have a higher wear rate than the un-reinforced matrix alloy while their frictional characteristics are very similar within the range of testing conditions. Combining these with the information gathered from worn-surface examinations and wear-debris analysis, it is suggested that there exists a certain threshold for the amount and size of graphite particulates in these composites to enable them to have improved tribological properties. (Copyright (c) 1997 Elsevier Science B.V., Amsterdam. All rights reserved.)

Estimation of magnetic relaxation property for CVD processed YBCO-coated conductors

International Nuclear Information System (INIS)

Takahashi, Y.; Kiuchi, M.; Otabe, E.S.; Matsushita, T.; Shikimachi, K.; Watanabe, T.; Kashima, N.; Nagaya, S.

2010-01-01

Ion Beam Assist Deposition/Chemical Vapor Deposition(IBAD/CVD)-processed YBCO-coated conductors with high critical current density J c at high magnetic fields are expected to be applied to superconducting equipments such as superconducting magnetic energy storage (SMES). For application to superconducting magnet in SMES one of the most important properties for superconductors is the relaxation property of superconducting current. In this paper, the relaxation property is investigated for IBAD/CVD-processed YBCO-coated conductors of the superconducting layer in the range of 0.18-0.90 μm. This property can be quantitatively characterized by the apparent pinning potential, U 0 *. It is found that U 0 * takes a smaller value due to the two-dimensional pinning mechanism at high magnetic fields for conductor with thinner superconducting layer. Although U 0 * decreases with increasing thickness at low magnetic fields at 20 K, it increases at high magnetic fields. The results are theoretically explained by the model of the flux creep and flow based on the dimensionality of flux pinning. Scaling analysis is examined for the dependence of U 0 * on the magnetic field, temperature and the layer thickness.

Investigation about the Chrome Steel Wire Arc Spray Process and the Resulting Coating Properties

Science.gov (United States)

Wilden, J.; Bergmann, J. P.; Jahn, S.; Knapp, S.; van Rodijnen, F.; Fischer, G.

2007-12-01

Nowadays, wire-arc spraying of chromium steel has gained an important market share for corrosion and wear protection applications. However, detailed studies are the basis for further process optimization. In order to optimize the process parameters and to evaluate the effects of the spray parameters DoE-based experiments had been carried out with high-speed camera shoots. In this article, the effects of spray current, voltage, and atomizing gas pressure on the particle jet properties, mean particle velocity and mean particle temperature and plume width on X46Cr13 wire are presented using an online process monitoring device. Moreover, the properties of the coatings concerning the morphology, composition and phase formation were subject of the investigations using SEM, EDX, and XRD-analysis. These deep investigations allow a defined verification of the influence of process parameters on spray plume and coating properties and are the basis for further process optimization.

Mechanical and tribological properties of ion beam-processed surfaces

International Nuclear Information System (INIS)

Kodali, P.

1998-01-01

The intent of this work was to broaden the applications of well-established surface modification techniques and to elucidate the various wear mechanisms that occur in sliding contact of ion-beam processed surfaces. The investigation included characterization and evaluation of coatings and modified surfaces synthesized by three surface engineering methods; namely, beam-line ion implantation, plasma-source ion implantation, and DC magnetron sputtering. Correlation among measured properties such as surface hardness, fracture toughness, and wear behavior was also examined. This dissertation focused on the following areas of research: (1) investigating the mechanical and tribological properties of mixed implantation of carbon and nitrogen into single crystal silicon by beam-line implantation; (2) characterizing the mechanical and tribological properties of diamond-like carbon (DLC) coatings processed by plasma source ion implantation; and (3) developing and evaluating metastable boron-carbon-nitrogen (BCN) compound coatings for mechanical and tribological properties. The surface hardness of a mixed carbon-nitrogen implant sample improved significantly compared to the unimplanted sample. However, the enhancement in the wear factor of this sample was found to be less significant than carbon-implanted samples. The presence of nitrogen might be responsible for the degraded wear behavior since nitrogen-implantation alone resulted in no improvement in the wear factor. DLC coatings have low friction, low wear factor, and high hardness. The fracture toughness of DLC coatings has been estimated for the first time. The wear mechanism in DLC coatings investigated with a ruby slider under a contact stress of 1 GPa was determined to be plastic deformation. The preliminary data on metastable BCN compound coatings indicated high friction, low wear factor, and high hardness

Influence of movement regime of stick-slip process on the size distribution of accompanying acoustic emission characteristics

Science.gov (United States)

Matcharashvili, Teimuraz; Chelidze, Tamaz; Zhukova, Natalia; Mepharidze, Ekaterine; Sborshchikov, Alexander

2010-05-01

Many scientific works on dynamics of earthquake generation are devoted to qualitative and quantitative reproduction of behavior of seismic faults. Number of theoretical, numerical or physical models are already designed for this purpose. Main assumption of these works is that the correct model must be capable to reproduce power law type relation for event sizes with magnitudes greater than or equal to a some threshold value, similar to Gutenberg-Richter (GR) law for the size distribution of earthquakes. To model behavior of a seismic faults in laboratory conditions spring-block experimental systems are often used. They enable to generate stick-slip movement, intermittent behavior occurring when two solids in contact slide relative to each other driven at a constant velocity. Wide interest to such spring-block models is caused by the fact that stick-slip is recognized as a basic process underlying earthquakes generation along pre-existing faults. It is worth to mention, that in stick slip experiments reproduction of power law, in slip events size distribution, with b values close or equal to the one found for natural seismicity is possible. Stick-slip process observed in these experimental models is accompanied by a transient elastic waves propagation generated during the rapid release of stress energy in spring-block system. Oscillations of stress energy can be detected as a characteristic acoustic emission (AE). Accompanying stick slip AE is the subject of intense investigation, but many aspects of this process are still unclear. In the present research we aimed to investigate dynamics of stick slip AE in order to find whether its distributional properties obey power law. Experiments have been carried out on spring-block system consisting of fixed and sliding plates of roughly finished basalt samples. The sliding block was driven with a constant velocity. Experiments have been carried out for five different stiffness of pulling spring. Thus five different regimes

Characteristics of recycled and electron beam irradiated high density polyethylene samples

International Nuclear Information System (INIS)

Cardoso, Jessica R.; Gabriel, Leandro; Geraldo, Aurea B.C.; Moura, Eduardo

2015-01-01

Polymers modification by irradiation is a well-known process that allows degradation and cross-linking in concurrent events; this last is expected when an increase of mechanical properties is required. Actually, the interest of recycling and reuse of polymeric material is linked to the increase of plastics ending up in waste streams. Therefore, these both irradiation and recycling process may be conducted to allow a new use to this material that would be discarded by an improvement of its mechanical properties. In this work, the High Density Polyethylene (HDPE) matrix has been recycled five times from original substrate. The electron beam irradiation process was applied from 50 kGy to 200 kGy in both original and recycled samples; in this way, mechanical properties and thermal characteristics were evaluated. The results of applied process and material characterization are discussed. (author)

Characteristics of recycled and electron beam irradiated high density polyethylene samples

Energy Technology Data Exchange (ETDEWEB)

Cardoso, Jessica R.; Gabriel, Leandro; Geraldo, Aurea B.C.; Moura, Eduardo, E-mail: jrcardoso@ipen.br, E-mail: lgabriell@gmail.com, E-mail: ageraldo@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

Polymers modification by irradiation is a well-known process that allows degradation and cross-linking in concurrent events; this last is expected when an increase of mechanical properties is required. Actually, the interest of recycling and reuse of polymeric material is linked to the increase of plastics ending up in waste streams. Therefore, these both irradiation and recycling process may be conducted to allow a new use to this material that would be discarded by an improvement of its mechanical properties. In this work, the High Density Polyethylene (HDPE) matrix has been recycled five times from original substrate. The electron beam irradiation process was applied from 50 kGy to 200 kGy in both original and recycled samples; in this way, mechanical properties and thermal characteristics were evaluated. The results of applied process and material characterization are discussed. (author)

Wave Characteristics of Temperature Inversion Process of Nighttime Radiation,

Science.gov (United States)

1983-12-09

CHARACTERISTICS OF TEMPERATURE INVERSION PROCESS OF NIGHTTIME RADIATION By: Zhou Mingyu and Zhang ¥i English pages: 8 Source: Kexue Tongbao, 1982, pp. 156...lJournal of Meteorology], 39 (1981), 1:70-81. 3. Drazin, P. G., J. Fluid. Mech., 4 (1958), 214-224. 4. Zhou Mingyu et al., QIXIANG XUEBAO, 38 (1980), 3: 250...258. 5. Emnanuel, C. B., B-L. Meteor., 5(1973), N(1/2)8 19-27. 6. Zhou Mingyu et al., J. Acoust. Soc., A. m., 68 (1980), 1: 303-308. 8 I iI

Characteristics and utilization of thermoplastic elastomers (TPE)-an overview

Energy Technology Data Exchange (ETDEWEB)

Roestamsjah, [R and D Center for Applied Chemistry, Indonesian Inst. of Sciences (Indonesia)

1998-10-01

The unique feature of thermoplastic elastomer, the combining of processing characteristics of thermoplastics with the physical properties of vulcanized rubber is reviewed. Highlights of TPE and its characteristics is aimed to generate interest in TPE, where SANS technique will be utilized for its characterization. The topics discussed include rubber elasticity, state of aggregation of polymers, microseparation in block copolymer system, application of TPE, and finally some notes in developing interest in TPE and SANS in Indonesia. (author)

Analysis of the emission characteristics of ion sources for high-value optical counting processes

International Nuclear Information System (INIS)

Beermann, Nils

2009-01-01

The production of complex high-quality thin film systems requires a detailed understanding of all partial processes. One of the most relevant partial processes is the condensation of the coating material on the substrate surface. The optical and mechanical material properties can be adjusted by the well-defined impingement of energetic ions during deposition. Thus, in the past, a variety of different ion sources were developed. With respect to the present and future challenges in the production of precisely fabricated high performance optical coatings, the ion emission of the sources has commonly not been characterized sufficiently so far. This question is addressed in the frame of this work which itself is thematically integrated in the field of process-development and -control of ion assisted deposition processes. In a first step, a Faraday cup measurement system was developed which allows the spatially resolved determination of the ion energy distribution as well as the ion current distribution. Subsequently, the ion emission profiles of six ion sources were determined depending on the relevant operating parameters. Consequently, a data pool for process planning and supplementary process analysis is made available. On the basis of the acquired results, the basic correlations between the operating parameters and the ion emission are demonstrated. The specific properties of the individual sources as well as the respective control strategies are pointed out with regard to the thin film properties and production yield. Finally, a synthesis of the results and perspectives for future activities are given. (orig.)

Chemical Characteristics and Antioxidant Properties of Crude Water Soluble Polysaccharides from Four Common Edible Mushrooms

Directory of Open Access Journals (Sweden)

Pei-Long Sun

2012-04-01

Full Text Available Four crude water soluble polysaccharides, CABP, CAAP, CFVP and CLDP, were isolated from common edible mushrooms, including Agaricus bisporus, Auricularia auricula, Flammulina velutipes and Lentinus edodes, and their chemical characteristics and antioxidant properties were determined. Fourier Transform-infrared analysis showed that the four crude polysaccharides were all composed of β-glycoside linkages. The major monosaccharide compositions were D-galactose, D-glucose and D-mannose for CABP, CAAP and CLDP, while CFVP was found to consist of L-arabinose, D-galactose, D-glucose and D-mannose. The main molecular weight distributions of CABP and the other three polysaccharides were 66.0 × 104 Da, respectively. Antioxidant properties of the four polysaccharides were evaluated in in vitro systems and CABP showed the best antioxidant properties. The studied mushroom species could potentially be used in part of well-balanced diets and as a source of antioxidant compounds.

Semi-Markov processes

CERN Document Server

Grabski

2014-01-01

Semi-Markov Processes: Applications in System Reliability and Maintenance is a modern view of discrete state space and continuous time semi-Markov processes and their applications in reliability and maintenance. The book explains how to construct semi-Markov models and discusses the different reliability parameters and characteristics that can be obtained from those models. The book is a useful resource for mathematicians, engineering practitioners, and PhD and MSc students who want to understand the basic concepts and results of semi-Markov process theory. Clearly defines the properties and

Optical properties of polydimethylsiloxane (PDMS) during nanosecond laser processing

Energy Technology Data Exchange (ETDEWEB)

Stankova, N.E., E-mail: nestankova@yahoo.com [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tsaridradsko shose Boul., Sofia 1784 (Bulgaria); Atanasov, P.A.; Nikov, Ru.G.; Nikov, R.G.; Nedyalkov, N.N.; Stoyanchov, T.R. [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tsaridradsko shose Boul., Sofia 1784 (Bulgaria); Fukata, N. [International Center for Materials for NanoArchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba 305-0044 (Japan); Kolev, K.N.; Valova, E.I.; Georgieva, J.S.; Armyanov, St.A. [Rostislaw Kaischew Institute of Physical Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Block 11, Sofia 1113 (Bulgaria)

2016-06-30

Highlights: • Ns-laser (266, 355, 532 and 1064 nm) processing of medical grade PDMS is performed. • Investigation of the optical transmittance as a function of the laser beam parameters. • Analyses of laser treated area by optical & laser microscope and μ-Raman spectrometry. • Application as (MEAs) neural interface for monitor and stimulation of neural activity. - Abstract: This article presents experimental investigations of effects of the process parameters on the medical grade polydimethylsiloxane (PDMS) elastomer processed by laser source with irradiation at UV (266 and 355 nm), VIS (532 nm) and NIR (1064 nm). Systematic experiments are done to characterize how the laser beam parameters (wavelength, fluence, and number of pulses) affect the optical properties and the chemical composition in the laser treated areas. Remarkable changes of the optical properties and the chemical composition are observed. Despite the low optical absorption of the native PDMS for UV, VIS and NIR wavelengths, successful laser treatment is accomplished due to the incubation process occurring below the polymer surface. With increasing of the fluence and the number of the pulses chemical transformations are revealed in the entire laser treated area and hence decreasing of the optical transmittance is observed. The incubation gets saturation after a certain number of pulses and the laser ablation of the material begins efficiently. At the UV and VIS wavelengths the number of the initial pulses, at which the optical transmittance begins to reduce, decreases from 16 up to 8 with increasing of the laser fluence up to 1.0, 2.5 and 10 J cm{sup −2} for 266, 355 and 532 nm, respectively. In the case of 1064 nm the optical transmittance begins to reduce at 11th pulse incident at a fluence of 13 J cm{sup −2} and the number of the pulses decreases to 8 when the fluence reaches value of 16 J cm{sup −2}. The threshold laser fluence needed to induce incubation process after certain

Novel food processing techniques

Directory of Open Access Journals (Sweden)

Vesna Lelas

2006-12-01

Full Text Available Recently, a lot of investigations have been focused on development of the novel mild food processing techniques with the aim to obtain the high quality food products. It is presumed also that they could substitute some of the traditional processes in the food industry. The investigations are primarily directed to usage of high hydrostatic pressure, ultrasound, tribomechanical micronization, microwaves, pulsed electrical fields. The results of the scientific researches refer to the fact that application of some of these processes in particular food industry can result in lots of benefits. A significant energy savings, shortening of process duration, mild thermal conditions, food products with better sensory characteristics and with higher nutritional values can be achieved. As some of these techniques act also on the molecular level changing the conformation, structure and electrical potential of organic as well as inorganic materials, the improvement of some functional properties of these components may occur. Common characteristics of all of these techniques are treatment at ambient or insignificant higher temperatures and short time of processing (1 to 10 minutes. High hydrostatic pressure applied to various foodstuffs can destroy some microorganisms, successfully modify molecule conformation and consequently improve functional properties of foods. At the same time it acts positively on the food products intend for freezing. Tribomechanical treatment causes micronization of various solid materials that results in nanoparticles and changes in structure and electrical potential of molecules. Therefore, the significant improvement of some rheological and functional properties of materials occurred. Ultrasound treatment proved to be potentially very successful technique of food processing. It can be used as a pretreatment to drying (decreases drying time and improves functional properties of food, as extraction process of various components

Polyhydroxyalkanoate (PHA: Review of synthesis, characteristics, processing and potential applications in packaging

Directory of Open Access Journals (Sweden)

E. Bugnicourt

2014-11-01

Full Text Available Polyhydroxyalkanoates (PHAs are gaining increasing attention in the biodegradable polymer market due to their promising properties such as high biodegradability in different environments, not just in composting plants, and processing versatility. Indeed among biopolymers, these biogenic polyesters represent a potential sustainable replacement for fossil fuel-based thermoplastics. Most commercially available PHAs are obtained with pure microbial cultures grown on renewable feedstocks (i.e. glucose under sterile conditions but recent research studies focus on the use of wastes as growth media. PHA can be extracted from the bacteria cell and then formulated and processed by extrusion for production of rigid and flexible plastic suitable not just for the most assessed medical applications but also considered for applications including packaging, moulded goods, paper coatings, non-woven fabrics, adhesives, films and performance additives. The present paper reviews the different classes of PHAs, their main properties, processing aspects, commercially available ones, as well as limitations and related improvements being researched, with specific focus on potential applications of PHAs in packaging.

Direct and mediated impacts of product and process characteristics on consumers’ choice of organic vs. conventional chicken

DEFF Research Database (Denmark)

Marian, Livia; Thøgersen, John

2013-01-01

There is a lack of research into why consumers value process characteristics. In this study, we test the hypothesis that the impact of process characteristics such as organic and free-range on consumers’ choices of food products is at least partly mediated through expected eating quality or taste...... expectations. In other words, the process characteristics partly function as cues to (eating) quality. Using a traditional metric conjoint approach based on an additive model, four product characteristics (production method, price, size and information about farmer and rearing conditions) were varied...... in a fractional factorial conjoint design, creating nine profiles of whole chickens. 384 Respondents rated the nine different chickens in terms of taste expectations and willingness to buy. Since the nine records for each respondent are not independent, we used linear mixed modelling for the mediation analysis...

The structure-property relationships of powder processed Fe-Al-Si alloys

Energy Technology Data Exchange (ETDEWEB)

Prichard, Paul D. [Iowa State Univ., Ames, IA (United States)

1998-02-23

Iron-aluminum alloys have been extensively evaluated as semi-continuous product such as sheet and bar, but have not been evaluated by net shape P/M processing techniques such as metal injection molding. The alloy compositions of iron-aluminum alloys have been optimized for room temperature ductility, but have limited high temperature strength. Hot extruded powder alloys in the Fe-Al-Si system have developed impressive mechanical properties, but the effects of sintering on mechanical properties have not been explored. This investigation evaluated three powder processed Fe-Al-Si alloys: Fe-15Al, Fe-15Al-2.8Si, Fe-15Al-5Si (atomic %). The powder alloys were produced with a high pressure gas atomization (HPGA) process to obtain a high fraction of metal injection molding (MIM) quality powder (D₈₄ < 32 μm). The powders were consolidated either by P/M hot extrusion or by vacuum sintering. The extruded materials were near full density with grain sizes ranging from 30 to 50 μm. The vacuum sintering conditions produced samples with density ranging from 87% to 99% of theoretical density, with an average grain size ranging from 26 μm to 104 μm. Mechanical property testing was conducted on both extruded and sintered material using a small punch test. Tensile tests were conducted on extruded bar for comparison with the punch test data. Punch tests were conducted from 25 to 550 C to determine the yield strength, and fracture energy for each alloy as a function of processing condition. The ductile to brittle transition temperature (DBTT) was observed to increase with an increasing silicon content. The Fe-15Al-2.8Si alloy was selected for more extensive testing due to the combination of high temperature strength and low temperature toughness due to the two phase α + DO₃ structure. This investigation provided a framework for understanding the effects of silicon in powder processing and mechanical property behavior of Fe-Al-Si alloys.

Willingness to Use Microbicides Is Affected by the Importance of Product Characteristics, Use Parameters, and Protective Properties

Science.gov (United States)

Morrow, Kathleen M.; Fava, Joseph L.; Rosen, Rochelle K.; Vargas, Sara; Barroso, Candelaria; Christensen, Anna L.; Woodsong, Cynthia; Severy, Lawrence

2008-01-01

Background Along with efficacy, a microbicide’s acceptability will be integral to its impact on the pandemic. Understanding Product Characteristics that users find most acceptable and determining who will use which type of product are key to optimizing use effectiveness. Objectives To evaluate psychometrically the Important Microbicide Characteristics (IMC) instrument and examine its relationship to willingness to use microbicides. Results Exploratory and confirmatory factor analyses revealed 2 IMC subscales (Cronbach’s coefficient α: Product Characteristics subscale (α = 0.84) and Protective Properties subscale (α = 0.89)). Significant differences on Product Characteristics subscale scores were found for history of douching (P = 0.002) and employment status (P = 0.001). Whether a woman used a method to prevent pregnancy or sexually transmitted disease (STD) in the last 3 months (P IMC instrument serves as a template for future studies of candidate microbicides. PMID:17325607

Study of Dynamic Characteristics of Slow-Changing Process

Directory of Open Access Journals (Sweden)

Yinong Li

2000-01-01

Full Text Available A vibration system with slow-changing parameters is a typical nonlinear system. Such systems often occur in the working and controlled process of some intelligent structures when vibration and deformation exist synchronously. In this paper, a system with slow-changing stiffness, damping and mass is analyzed in an intelligent structure. The relationship between the amplitude and the frequency of the system is studied, and its dynamic characteristic is also discussed. Finally, a piecewise linear method is developed on the basis of the asymptotic method. The simulation and the experiment show that a suitable slow-changing stiffness can restrain the amplitude of the system when the system passes through the resonant region.

Power characteristics of the metal compounds formation process during the friction stir welding

Directory of Open Access Journals (Sweden)

Rzaev Radmir

2017-01-01

Full Text Available An influence of the power characteristics on the formation process of the uniform metals compound during the welding with friction stirringis being examined in this article.A dependency between the machine-tool engine power input and the instrument tilt during the FSW for the aluminum alloy AD31, copper alloy M1, titanium alloy OT4-1 and steel St-3 low-alloyed has been explored. A question of the stabilization of power consumption process while the establishment of superplastic condition of welded metal during the FSW has also been reviewed. A dependency revealed between the power characteristics, the geometry of the formation, the rotation speeds, the longitudinal displacement of the tool and its dimensions for fixed values of the parameters during the FSW.

Changes in UO2 powder properties during processing via BNFL's binderless route

International Nuclear Information System (INIS)

Bromely, A.P.; Logsdon, R.; Roberts, V.A.

1997-01-01

The Short Binderless Route (SBR) has been developed for Mixed Oxide fuel production in BNFL's MOX Demonstration Facility (MDF) and the Sellafield MOX Plant (SMP). It is a compact process which enables good homogenisation of the Pu/U mixture and production of free flowing press feed materials. The equipment used to achieve this consists of an attritor mill to provide homogenization and a spheroidiser to provide press feed granules. As for other powder processes, the physical properties of the UO 2 powder can affect the different process stages and consequently a study of some of these effects has been carried out. The aim of the work were to gain a better understanding of the process, to consequently optimize press feed material quality and to also maintain powder hold-up levels in the equipment at a minimum. The paper considers the effects of milling processes on powder morphology and powder surface effects, on the granulation process and also on powder and granule bulk properties such as pour, tap and compaction densities. Results are discussed in terms of powder properties such as powder cohesivity, morphology and particle size. UO 2 powder derived from both the Integrated Dry Route (IDR) and the Ammonium Di-Uranate (ADU) Route are considered. Small (1 kg) scale work has been carried out which has been confirmed by larger (25 kg) scale trials. The work shows that IDR powder with differing morphologies and ADU powder can be successfully processed via the SBR route. (author). 4 figs, 4 tabs

The Characteristic of the Process of Students' Metacognition in Solving Calculus Problems

Science.gov (United States)

Purnomo, Dwi; Nusantara, Toto; Subanji; Rahardjo, Swasono

2017-01-01

This article is the result of research aims to describe the patterns and characteristics of the process of metacognition student of mathematics in solving calculus problems. Description was done by looking at changes in "awareness," "evaluation," and "regulation" as components of metacognition. The changes in…

Fundamental properties of cooperative contagion processes

Science.gov (United States)

Chen, Li; Ghanbarnejad, Fakhteh; Brockmann, Dirk

2017-10-01

We investigate the effects of cooperativity between contagion processes that spread and persist in a host population. We propose and analyze a dynamical model in which individuals that are affected by one transmissible agent A exhibit a higher than baseline propensity of being affected by a second agent B and vice versa. The model is a natural extension of the traditional susceptible-infected-susceptible model used for modeling single contagion processes. We show that cooperativity changes the dynamics of the system considerably when cooperativity is strong. The system exhibits discontinuous phase transitions not observed in single agent contagion, multi-stability, a separation of the traditional epidemic threshold into different thresholds for inception and extinction as well as hysteresis. These properties are robust and are corroborated by stochastic simulations on lattices and generic network topologies. Finally, we investigate wave propagation and transients in a spatially extended version of the model and show that especially for intermediate values of baseline reproduction ratios the system is characterized by various types of wave-front speeds. The system can exhibit spatially heterogeneous stationary states for some parameters and negative front speeds (receding wave fronts). The two agent model can be employed as a starting point for more complex contagion processes, involving several interacting agents, a model framework particularly suitable for modeling the spread and dynamics of microbiological ecosystems in host populations.

Fundamental properties of cooperative contagion processes

International Nuclear Information System (INIS)

Chen, Li; Ghanbarnejad, Fakhteh; Brockmann, Dirk

2017-01-01

We investigate the effects of cooperativity between contagion processes that spread and persist in a host population. We propose and analyze a dynamical model in which individuals that are affected by one transmissible agent A exhibit a higher than baseline propensity of being affected by a second agent B and vice versa. The model is a natural extension of the traditional susceptible-infected-susceptible model used for modeling single contagion processes. We show that cooperativity changes the dynamics of the system considerably when cooperativity is strong. The system exhibits discontinuous phase transitions not observed in single agent contagion, multi-stability, a separation of the traditional epidemic threshold into different thresholds for inception and extinction as well as hysteresis. These properties are robust and are corroborated by stochastic simulations on lattices and generic network topologies. Finally, we investigate wave propagation and transients in a spatially extended version of the model and show that especially for intermediate values of baseline reproduction ratios the system is characterized by various types of wave-front speeds. The system can exhibit spatially heterogeneous stationary states for some parameters and negative front speeds (receding wave fronts). The two agent model can be employed as a starting point for more complex contagion processes, involving several interacting agents, a model framework particularly suitable for modeling the spread and dynamics of microbiological ecosystems in host populations. (paper)

Effect of Partial Substitution of Neodymium with Praseodymium on the Magnetic and Process Properties of Sintered Magnets of Type NdFeB

Science.gov (United States)

Dormidontov, N. A.; Dormidontov, A. G.; Lileev, A. S.; Kamynin, A. V.; Lukin, A. A.

2017-01-01

The effect of substitution of neodymium with praseodymium in sintered magnets of type NdFeB on their magnetic and process properties in the concentration range of [Pr] = 0 - 13 wt.% is studied. The special features of milling of the alloys, sintering processes and heat treatments in the production of magnets containing praseodymium are discussed. Hysteresis characteristics of B r ≥ 1.2 T, H cJ ≥ 1200 kA/m, H cb ≥ 880 kA/m, H k ≥ 960 kA/m, and BH max ≥ 280 kJ/m3 are obtained for magnets with composition (in wt.%) 33 Nd, 10 Pr, 1.5 (Ti + Al + Cu), 1.3 B, the remainder Fe.

Evaluation of quality characteristics and functional properties of mechanically deboned chicken meats treated with different dose rates of ionizing radiation and use of antioxidants

International Nuclear Information System (INIS)

Brito, Poliana de Paula

2012-01-01

The Mechanically Deboned chicken meat (MDCM) is used in traditional meat products, in greater proportion in those emulsified, replacing meat raw materials more expensive. The raw material can have high MDCM the microbial load, as a result of contamination during processing or failure during the evisceration. The irradiation process is accepted as one of the most effective technologies when compared to conventional techniques of preservation, to reduce contamination of pathogens and spoilage. However, little information is available about the use and effects of different dose rates of ionizing radiation processing. Irradiation causes chemical changes in food, a major cause of deterioration of quality of raw or cooked meat products during refrigerated storage, frozen. The objective of this study was to evaluate the effects of different dose rates of ionizing radiation on the production of Thiobarbituric Acid Reactive Substances (TBARS), color, microbiological and sensory characteristics of mechanically deboned chicken added or without added antioxidants, during the cold storage and evaluation of functional properties. The results showed that among the tested dose rates using cobalt-60 source, dose rate of 4.04 kGy.h-1 was the best for processing MDCM. Furthermore, the use of the combination of rosemary antioxidant and α-tocopherol were able to reduce lipid oxidation generated by irradiation of the samples, showed a synergistic effect to the processing with ionizing radiation in reduction of psychrotrophic bacteria count and contributed to a better sensory quality. The use of radiation in the processing FDMI did not adversely affect the functional properties studied. (author)

Computerized property prediction and process planning in heat treatment of steels

Energy Technology Data Exchange (ETDEWEB)

Gergely, M. (Steel Advisory Centre for Industrial Technologies (SACIT), Budapest (Hungary)); Somogyi, S. (Steel Advisory Centre for Industrial Technologies (SACIT), Budapest (Hungary)); Kohlheb, R. (Steel Advisory Centre for Industrial Technologies (SACIT), Budapest (Hungary))

1994-01-01

Recent years have seen widespread interest in the establishment of prediction methods, based on phenomenological description and computer simulation of transformation processes during heat treatment, and in the introduction of software for technological planning. The steady development of this approach is aimed at meeting the requirement of metallurgists, design engineers dealing with material selection and dimensioning, and technologists planning heat treatment processes. Research in this field of computer simulation has been concentrated so far on two main areas of interest: . Modelling of transformation processes and the prediction of microstructures and/or properties, . Developing program packages to help solve concrete tasks such as material selection, on-line process control and monitoring, and the design of heat-treating operations. During the last two decades in the field of heat treatment, various mathematical models with different accuracy and complexity have been developed. In this paper, an attempt is made to outline some important results in computer simulation and computerized property prediction without aiming at completeness. The topic is restricted to quenched and tempered, and case-hardened steels. (orig.)

Correlation of mechanical and electrical properties with processing variables in MWCNT reinforced thermoplastic nanocomposites

DEFF Research Database (Denmark)

Doagou-Rad, Saeed; Islam, Aminul; Jensen, Jakob Søndergaard

2018-01-01

The influence of the processing variables and nanotube content on the mechanical and electrical properties of polyamide 6,6-based nanocomposites reinforced with multi-walled carbon nanotubes is investigated. Results show that variation in the processing variables such as compounding method....... Different processing parameters required for achieving optimal mechanical and electrical performances are also found. Correlation between processing parameters and microstructure within the nanocomposites is studied. Results show that variation of the processing parameters defines the existence or absence...... discussed using scanning and transmission electron microscopy, rheological and crystallization investigations. The research provides a recipe to manufacture the tailored nanocomposite with the specified properties for various industrial applications....

[Study on pharmacologic action characteristics of traditional Chinese medicines distributed along liver meridian based on medicinal properties combinations].

Science.gov (United States)

Guo, Hong-Ling; Gu, Hao; Wang, Yun; Qiao, Yan-Jiang

2014-07-01

To establish a characterization system of traditional Chinese medicinal properties in line with modern scientific cognition regularity, in order to reveal properties of traditional Chinese medicines distributed along liver meridian and relations of effects of medicinal properties. By collecting data about traditional Chinese medicinal properties recorded in the Pharmacopoeia of the People's Republic of China (2005 Edition), literature and data about pharmacological effects of traditional Chinese medicines recorded in the Chinese Materia Medica, by using the method of association rules, the authors dug pharmacological effect rules corresponds to relevant medicinal property combinations, with the medicinal property combination of traditional Chinese medicines distributed along liver meridian as the target. It was found that either obvious different pharmacological effects or identical pharmacological characteristics existed in traditional Chinese medicines distributed along liver meridian. With the aim to explore the correlations between traditional Chinese medicine medicinal properties and pharmacological effects, the authors linked the traditional Chinese medicine theory with modern research achievements, in order to provide the ideas and methods for interpreting mechanisms of medicinal properties.

Microstructure and Mechanical Properties of J55ERW Steel Pipe Processed by On-Line Spray Water Cooling

Directory of Open Access Journals (Sweden)

Zejun Chen

2017-04-01

Full Text Available An on-line spray water cooling (OSWC process for manufacturing electric resistance welded (ERW steel pipes is presented to enhance their mechanical properties and performances. This technique reduces the processing needed for the ERW pipe and overcomes the weakness of the conventional manufacturing technique. Industrial tests for J55 ERW steel pipe were carried out to validate the effectiveness of the OSWC process. The microstructure and mechanical properties of the J55 ERW steel pipe processed by the OSWC technology were investigated. The optimized OSWC technical parameters are presented based on the mechanical properties and impact the performance of steel pipes. The industrial tests show that the OSWC process can be used to efficiently control the microstructure, enhance mechanical properties, and improve production flexibility of steel pipes. The comprehensive mechanical properties of steel pipes processed by the OSWC are superior to those of other published J55 grade steels.

Sensitometric characteristics of D-, E- and F-speed dental radiographic films in manual and automatic processing

Directory of Open Access Journals (Sweden)

Jahangir Haghani

2012-12-01

Full Text Available BACKGROUND: The purpose of this study was to evaluate the sensitometric characteristics of Ultraspeed, Ektaspeed Plus and Insight dental radiographic films using manual and automatic processing systems. METHODS: In this experimental invitro study, an aluminum step-wedge was used to construct characteristic curves for D-, E- and F-speed radiographic films (Kodak Eastman, Rochester, USA. All films were processed in Iranian processing solution (chemical industries Co., Iran, Tehran both manually and automatically in a period of six days. Unexposed films of three types were processed manually and automatically to determine base plus fog density. Speed and film contrast were measured according to International Standard Organization definition. RESULTS: There was significant difference in density obtained with the D-, E- and F-speed films in both manually and automatically processing systems (P < 0.001. There was significant difference in density obtained with the Ultraspeed and insight films. There was no significant difference in contrast obtained with the D-, E- and F-speed films in both manually and automatically processing systems (P = 0.255 , P = 0.26. There was significant difference in speed obtained with the D-, E- and F-speed films in both manually and automatically processing systems (P = 0.034, P = 0.04. CONCLUSIONS: The choice of processing system can affect radiographic characteristics. The F-speed film processed in automatic system has greater speed in comparison with manual processing system, and it provides a further reduction in radiation exposure without detriment to image quality.

FOOD PROCESSING TECHNOLOGY AS A MEDIATOR OF FUNCTIONALITY. STRUCTURE-PROPERTY-PROCESS RELATIONSHIPS

Directory of Open Access Journals (Sweden)

Ester Betoret

2015-02-01

Full Text Available During the last years, the food industry has been facing technical and economic changes both in society and in the food processing practices, paying high attention to food products that meet the consumers´ demands. In this direction, the study areas in food process and products have evolved mainly from safety to other topics such as quality, environment or health. The improvement of the food products is now directed towards ensuring nutritional and specific functional benefits. Regarding the processes evolution, they are directed to ensure the quality and safety of environmentally friendly food products produced optimizing the use of resources, minimally affecting or even enhancing their nutritional and beneficial characteristics. The product structure both in its raw form and after processing plays an important role maintaining, enhancing and delivering the bioactive compounds in the appropriate target within the organism. The aim of this review is to make an overview on some synergistic technologies that can constitute a technological process to develop functional foods, enhancing the technological and/or nutritional functionality of the food products in which they are applied. More concretely, the effect of homogenization, vacuum impregnation and drying operations on bioactive compounds have been reviewed, focusing on the structure changes produced and its relationship on the product functionality, as well as on the parameters and the strategies used to quantify and increase the achieved functionality.

Influence of processing on physicochemical and antioxidant properties of apricot (Prunus armeniaca L. variety Narmo

Directory of Open Access Journals (Sweden)

S.M. Wani

2016-12-01

Full Text Available Fresh apricot pulp and its processed products (bar, chutney, and leather were analyzed for physicochemical (moisture content, titrable acidity (TA, ascorbic acid, and percent reducing sugars and antioxidant properties (2,2-diphenyl-l-picrylhydrazyl (DPPH, reducing power, total phenolics, lipid peroxidation, ferric reducing antioxidant potential, and hydroxyl radical scavenging activity. Reducing sugars, TA, and ascorbic acid content were found to be higher in the processed products than the fresh pulp. A significant difference in the antioxidant properties between the fresh apricot pulp and its processed products was observed. The difference in antioxidant properties between the fresh and the processed products may be attributed to the partial degradation of the bioactive compounds by the action of heat during processing. Among the processed products, apricot bar showed the highest DPPH radical scavenging activity, lipid peroxidation, and hydroxyl radical scavenging activity. Therefore, production of apricot bar could a suitable option for processing of apricots.

Optical characteristics of novel bulk and nanoengineered laser host materials

Science.gov (United States)

Prasad, Narasimha S.; Sova, Stacey; Kelly, Lisa; Bevan, Talon; Arnold, Bradley; Cooper, Christopher; Choa, Fow-Sen; Singh, N. B.

2018-02-01

The hexagonal apatite single crystals have been investigated for their applications as laser host materials. Czochralksi and flux growth methods have been utilized to obtain single crystals. For low temperature processing (useful properties as laser hosts and bone materials. Calcium lanthanum silicate (Nd-doped) and lanthanum aluminate material systems were studied in detail. Nanoengineered calcium and lanthanum based silicates were synthesized by a solution method and their optical and morphological characteristics were compared with Czochralski grown bulk hydroxyapatite single crystals. Materials were evaluated by absorbance, fluorescence and Raman characteristics. Neodymium, iron and chromium doped crystals grown by a solution method showed weak but similar optical properties to that of Czochralski grown single crystals.

Characteristics of Chemical and Functional Properties of Modified Cassava Flour (Manihot esculenta) by Autoclaving-Cooling Cycles Method

Science.gov (United States)

Cecep Erwan Andriansyah, Raden; Rahman, Taufik; Herminiati, Ainia; Rahman, Nurhaidar; Luthfiyanti, Rohmah

2017-12-01

The modified cassava flour can be made using the method of the autoclaving cooling cycle (AAC). The stability of the warming can be seen from the decreasing value of breakdown viscosity, while the stability of the stirring process can be seen by the decreasing value of setback viscosity. The stages of research include: (1) the making of cassava flour, (2) the making of modified cassava flour by the method of treatment of ACC with a variety of flour concentration and autoclaving time, (3) chemical analysis of the moisture, ash, fat, protein, carbohydrate; The functional properties of the pasting characteristics to the initial temperature of the pasting, peak viscosity, hot paste viscosity, breakdown viscosity, cold paste viscosity and setback viscosity. The result shows that cassava flour modified by treatment of flour concentration 16% and autoclaving time 41 minutes having pasting code and pasting viscosity which is resistant to high temperature. Flour with this character is flour that is expected to maintain the texture of processed products with a paste form that remains stable. Utilization of modified cassava flour by the ACC method can be applied to the pasting product such as noodle and spaghetti, hoping to support for food diversification program to reduce dependence on wheat flour in Indonesia.

Microstructure, Mechanical and Corrosion Properties of Friction Stir-Processed AISI D2 Tool Steel

Science.gov (United States)

Yasavol, Noushin; Jafari, Hassan

2015-05-01

In this study, AISI D2 tool steel underwent friction stir processing (FSP). The microstructure, mechanical properties, and corrosion resistance of the FSPed materials were then evaluated. A flat WC-Co tool was used; the rotation rate of the tool varied from 400 to 800 rpm, and the travel speed was maintained constant at 385 mm/s during the process. FSP improved mechanical properties and produced ultrafine-grained surface layers in the tool steel. Mechanical properties improvement is attributed to the homogenous distribution of two types of fine (0.2-0.3 μm) and coarse (1.6 μm) carbides in duplex ferrite-martensite matrix. In addition to the refinement of the carbides, the homogenous dispersion of the particles was found to be more effective in enhancing mechanical properties at 500 rpm tool rotation rate. The improved corrosion resistance was observed and is attributed to the volume fraction of low-angle grain boundaries produced after friction stir process of the AISI D2 steel.

Critical solvent properties affecting the particle formation process and characteristics of celecoxib-loaded plga microparticles via spray-drying.

Science.gov (United States)

Wan, Feng; Bohr, Adam; Maltesen, Morten Jonas; Bjerregaard, Simon; Foged, Camilla; Rantanen, Jukka; Yang, Mingshi

2013-04-01

It is imperative to understand the particle formation mechanisms when designing advanced nano/microparticulate drug delivery systems. We investigated how the solvent power and volatility influence the texture and surface chemistry of celecoxib-loaded poly (lactic-co-glycolic acid) (PLGA) microparticles prepared by spray-drying. Binary mixtures of acetone and methanol at different molar ratios were applied to dissolve celecoxib and PLGA prior to spray-drying. The resulting microparticles were characterized with respect to morphology, texture, surface chemistry, solid state properties and drug release profile. The evaporation profiles of the feed solutions were investigated using thermogravimetric analysis (TGA). Spherical PLGA microparticles were obtained, irrespectively of the solvent composition. The particle size and surface chemistry were highly dependent on the solvent power of the feed solution. An obvious burst release was observed for the microparticles prepared by the feed solutions with the highest amount of poor solvent for PLGA. TGA analysis revealed distinct drying kinetics for the binary mixtures. The particle formation process is mainly governed by the PLGA precipitation rate, which is solvent-dependent, and the migration rate of celecoxib molecules during drying. The texture and surface chemistry of the spray-dried PLGA microparticles can therefore be tailored by adjusting the solvent composition.

Mathematical simulation of processes in horizontal steam generator and the program of calculation of its characteristics

Energy Technology Data Exchange (ETDEWEB)

Titov, V.F.; Zorin, V.M.; Gorburov, V.I. [OKB Gidropress, Moscow Energy Inst. (Russian Federation)

1995-12-31

On the basis of mathematical models describing the processes in horizontal steam generator (SG) the code giving the possibility to calculate the hydrodynamical characteristics in any point of water volume, has been developed. The code simulates the processes in SG in the stationary (or quasi-stationary) mode or operation only. The code may be used as a next step to calculations of the SG characteristics in the non-stationary modes of operation.

Mathematical simulation of processes in horizontal steam generator and the program of calculation of its characteristics

Energy Technology Data Exchange (ETDEWEB)

Titov, V F; Zorin, V M; Gorburov, V I [OKB Gidropress, Moscow Energy Inst. (Russian Federation)

1996-12-31

On the basis of mathematical models describing the processes in horizontal steam generator (SG) the code giving the possibility to calculate the hydrodynamical characteristics in any point of water volume, has been developed. The code simulates the processes in SG in the stationary (or quasi-stationary) mode or operation only. The code may be used as a next step to calculations of the SG characteristics in the non-stationary modes of operation.

Rheological, Colour and Processing Properties of Polypropylene Masterbatches for Nanocomposite Fibre Preparation

Directory of Open Access Journals (Sweden)

Štefan Krivoš

2017-12-01

Full Text Available Asia’s current dominance of the global production of standard types of chemical fibres requires the sophistication of European fibre and textile products. Modifying the mass or surface of materials using nanotechnologies is one of the most promising ways to ensure the special, mono- and multi-functionally modified fibre properties of clothing and technical textiles. The permanent antimicrobial treatment of fibre mass represents one the most desired functional modifi cations of chemical fibres. It involves the use of an antimicrobial additive masterbatch with the appropriate rheological, colour and processing properties required for the preparation of antimicrobial modified fibres. This article presents the results of our study of the effect of two types of nanoadditives (nanosilica and nanocalcium carbonate as potential carriers of an AMB active ingredient, and the effect of stearic acid, polyethylene glycol and propylene oxide as various dispersing systems on the rheological, colour and processing properties of polypropylene nanoadditive masterbatches. The obtained experimental results are evaluated in terms of the suitability of the properties of prepared nanoadditive masterbatches for the preparation of nanocomposite polypropylene fibres.

Magnetic materials fundamentals, products, properties, applications

CERN Document Server

Hilzinger, Rainer

2013-01-01

At a practical level, this compendium reviews the basics of soft and hard magnetic materials, discusses the advantages of the different processing routes for the exploitation of the magnetic properties and hence assists in proper, fail-safe and economic application of magnetic materials. Essential guidelines and formulas for the calculation of the magnetic and electrical properties, temperature and long-term stability of permanent magnets, of inductive components and magnetic shielding are compiled. Selected fields of application and case studies illustrate the large diversity of technical applications. Application engineers will appreciate the comprehensive compilation of the properties and detailed characteristic curves of modern soft and hard magnetic materials. Materials scientists will enjoy the presentation of the different processing routes and their impact on the magnetic properties and students will profit from the survey from the basics of magnetism down to the applications in inductive components, ...

A Study on N{sub 2}O Direct Oxidation Process with Re-oxidation Annealing for the Improvement of Interface Properties in 4H-SiC MOS Capacitor

Energy Technology Data Exchange (ETDEWEB)

Cho, Doohyung; Park, Kunsik; Yoo, Seongwook; Kim, Sanggi; Lee, Jinhwan; Kim, Kwangsoo [Electronics and Telecommunications Research Institute (ETRI), Daejeon (Korea, Republic of)

2017-08-15

The effect of N{sub 2}O direct oxidation processes with re-oxidation on SiC/SiO{sub 2} interface characteristics has been investigated. With different oxidation and post oxidation annealing (POA) processes, the flat-band voltage, effective dielectric charge density, and interface trap density are obtained from the capacitance-voltage curves. For the proposed N{sub 2}O direct oxidation processes with re-oxidation, oxides were grown in N{sub 2}O ambient, diluted in high-purity N{sub 2} to 10% concentration, for 5 h at 1230 ℃. After the growth, some samples were annealed additionally at 1200 ℃ in O{sub 2} or H{sub 2}O for 20 min. N{sub 2}O direct oxidation with re-oxidation processes was confirmed that SiC/SiO{sub 2} interface properties and dielectric stability have better performance than with other conventional oxidation processes. This oxidation technique is expected to improve gate dielectric stability for application to SiC MOS devices; in particular, it can be used to obtain high-quality SiC/SiO{sub 2} interface properties.

Effect of simulated mechanical recycling processes on the structure and properties of poly(lactic acid).

Science.gov (United States)

Beltrán, F R; Lorenzo, V; Acosta, J; de la Orden, M U; Martínez Urreaga, J

2018-06-15

The aim of this work is to study the effects of different simulated mechanical recycling processes on the structure and properties of PLA. A commercial grade of PLA was melt compounded and compression molded, then subjected to two different recycling processes. The first recycling process consisted of an accelerated ageing and a second melt processing step, while the other recycling process included an accelerated ageing, a demanding washing process and a second melt processing step. The intrinsic viscosity measurements indicate that both recycling processes produce a degradation in PLA, which is more pronounced in the sample subjected to the washing process. DSC results suggest an increase in the mobility of the polymer chains in the recycled materials; however the degree of crystallinity of PLA seems unchanged. The optical, mechanical and gas barrier properties of PLA do not seem to be largely affected by the degradation suffered during the different recycling processes. These results suggest that, despite the degradation of PLA, the impact of the different simulated mechanical recycling processes on the final properties is limited. Thus, the potential use of recycled PLA in packaging applications is not jeopardized. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dielectric Characteristics of Microstructural Changes and Property Evolution in Engineered Materials

Science.gov (United States)

Clifford, Jallisa Janet

Heterogeneous materials are increasingly used in a wide range of applications such as aerospace, civil infrastructure, fuel cells and many others. The ability to take properties from two or more materials to create a material with properties engineered to needs is always very attractive. Hence heterogeneous materials are evolving into more complex formulations in multiple disciplines. Design of microstructure at multiple scales control the global functional properties of these materials and their structures. However, local microstructural changes do not directly cause a proportional change to the global properties (such as strength and stiffness). Instead, local changes follow an evolution process including significant interactions. Therefore, in order to understand property evolution of engineered materials, microstructural changes need to be effectively captured. Characterizing these changes and representing them by material variables will enable us to further improve our material level understanding. In this work, we will demonstrate how microstructural features of heterogeneous materials can be described quantitatively using broadband dielectric spectroscopy (BbDS). The frequency dependent dielectric properties can capture the change in material microstructure and represent these changes in terms of material variables, such as complex permittivity. These changes in terms of material properties can then be linked to a number of different conditions, such as increasing damage due to impact or fatigue. Two different broadband dielectric spectroscopy scanning modes are presented: bulk measurements and continuous scanning to measure dielectric property change as a function of position across the specimen. In this study, we will focus on ceramic materials and fiber reinforced polymer matrix composites as test bed material systems. In the first part of the thesis, we will present how different micro-structural design of porous ceramic materials can be captured

Mining manufacturing data for discovery of high productivity process characteristics.

Science.gov (United States)

Charaniya, Salim; Le, Huong; Rangwala, Huzefa; Mills, Keri; Johnson, Kevin; Karypis, George; Hu, Wei-Shou

2010-06-01

Modern manufacturing facilities for bioproducts are highly automated with advanced process monitoring and data archiving systems. The time dynamics of hundreds of process parameters and outcome variables over a large number of production runs are archived in the data warehouse. This vast amount of data is a vital resource to comprehend the complex characteristics of bioprocesses and enhance production robustness. Cell culture process data from 108 'trains' comprising production as well as inoculum bioreactors from Genentech's manufacturing facility were investigated. Each run constitutes over one-hundred on-line and off-line temporal parameters. A kernel-based approach combined with a maximum margin-based support vector regression algorithm was used to integrate all the process parameters and develop predictive models for a key cell culture performance parameter. The model was also used to identify and rank process parameters according to their relevance in predicting process outcome. Evaluation of cell culture stage-specific models indicates that production performance can be reliably predicted days prior to harvest. Strong associations between several temporal parameters at various manufacturing stages and final process outcome were uncovered. This model-based data mining represents an important step forward in establishing a process data-driven knowledge discovery in bioprocesses. Implementation of this methodology on the manufacturing floor can facilitate a real-time decision making process and thereby improve the robustness of large scale bioprocesses. 2010 Elsevier B.V. All rights reserved.

Determination of Properties of Selected Fresh and Processed Medicinal Plants

Directory of Open Access Journals (Sweden)

Shirley G. Cabrera

2015-11-01

Full Text Available The study aimed to determine the chemical properties, bioactive compounds, antioxidant activity and toxicity level of fresh and processed medicinal plants such as corn (Zea mays silk, pancitpancitan (Peperomiapellucida leaves, pandan (Pandanus amaryllifolius leaves, and commercially available tea. The toxicity level of the samples was measured using the Brine Shrimp Lethality Assay (BSLA. Statistical analysis was done using Statistical Package for Social Sciences (SPSS. Results showed that in terms of chemical properties there is significant difference between fresh and processed corn silk except in crude fiber content was noted. Based on proximate analyses of fresh and processed medicinal plants specifically in terms of % moisture, %crude protein and % total carbohydrates were also observed. In addition, there is also significant difference on bioactive compound contents such as total flavonoids and total phenolics between fresh and processed corn silk except in total vitamin E (TVE content. Pandan and pancit-pancitan showed significant difference in all bioactive compounds except in total antioxidant content (TAC. Fresh pancit-pancitan has the highest total phenolics content (TPC and TAC, while the fresh and processed corn silk has the lowest TAC and TVE content, respectively. Furthermore, results of BSLA for the three medicinal plants and commercially available tea extract showed after 24 hours exposure significant difference in toxicity level was observed. The percentage mortality increased with an increase in exposure time of the three medicinal plants and tea extract. The results of the study can served as baseline data for further processing and commercialization of these medicinal plants.

Thermoelectric properties of P-type Sb2Te3 thick film processed by a screen-printing technique and a subsequent annealing process

International Nuclear Information System (INIS)

Kim, Sun Jin; We, Ju Hyung; Kim, Jin Sang; Kim, Gyung Soo; Cho, Byung Jin

2014-01-01

Highlights: • We report on thermoelectric properties of screen-printed Sb 2 Te 3 thick film. • Subsequent annealing process determines thermoelectric properties of Sb 2 Te 3 film. • Annealing in tellurium powder ambient contributes to tellurium-rich Sb 2 Te 3 film. • Annealing in tellurium powder ambient enhances carrier mobility of Sb 2 Te 3 film. -- Abstract: We herein report the thermoelectric properties of Sb 2 Te 3 thick film fabricated by a screen-printing technique and a subsequent annealing process. Each step of the screen-printing fabrication process of Sb 2 Te 3 thick film is described in detail. It was found that the subsequent annealing process must be carefully designed to achieve good thermoelectric properties of the screen-printed film. The results show that the annealing of the screen-printed Sb 2 Te 3 thick film together with tellurium powder in the same process chamber significantly improves the carrier mobility by increasing the average scattering time of the carrier in the film, resulting in a large improvement of the power factor. By optimizing the annealing process, we achieved a maximum thermoelectric figure-of-merit, ZT, of 0.32 at room temperature, which is slightly higher than that of bulk Sb 2 Te 3 . Because screen-printing is a simple and low-cost process and given that it is easy to scale up to large sizes, this result will be useful for the realization of large, film-type thermoelectric devices

Spark Plasma Sintering of Co{sub 80}Ni{sub 20} nanopowders synthesized by polyol process and their magnetic and mechanical properties

Energy Technology Data Exchange (ETDEWEB)

Ouar, Nassima [Laboratoire des Sciences des Procédés et Matériaux, LSPM, CNRS, UPR 3407, Université Paris XIII, 99 Avenue J.B. Clément, 93430 Villetaneuse (France); Bousnina, Mohamed Ali [Laboratoire des Sciences des Procédés et Matériaux, LSPM, CNRS, UPR 3407, Université Paris XIII, 99 Avenue J.B. Clément, 93430 Villetaneuse (France); Unité de Recherche 99/UR12-30, Faculté des Sciences de Bizerte, Université de Carthage, 7021 Jarzouna (Tunisia); Schoenstein, Frédéric; Mercone, Silvana; Brinza, Ovidiu; Farhat, Samir [Laboratoire des Sciences des Procédés et Matériaux, LSPM, CNRS, UPR 3407, Université Paris XIII, 99 Avenue J.B. Clément, 93430 Villetaneuse (France); Jouini, Noureddine, E-mail: jouini@univ-paris13.fr [Laboratoire des Sciences des Procédés et Matériaux, LSPM, CNRS, UPR 3407, Université Paris XIII, 99 Avenue J.B. Clément, 93430 Villetaneuse (France)

2014-12-05

Highlights: • Nanoparticles of Co{sub 80}Ni{sub 20} alloy were prepared by reduction in polyol medium. • SPS consolidation of these nanoparticles led to bulk nanostructured alloy. • Nanowires present hard magnetic behavior contrarily to nanospheres. • Tunable magnetic properties are achieved from hard to soft character. • Tunable mechanical behavior is achieved from ductile material to almost brittle one. - Abstract: A bottom-up process to elaborate nanostructured cobalt materials is here described. We first, synthesized Co{sub 80}Ni{sub 20} nanowires with a mean length L ∼ 270 nm and a mean diameter d ∼ 7 nm and Co{sub 80}Ni{sub 20} nanospheres with a mean diameter D ∼ 200 nm. This was done by a polyol process in presence of Ruthenium (III) chloride hydrate nucleating agent. Then the as-obtained nanopowders were consolidated by spark plasma sintering (SPS) in order to limit the grain size growth. Nanostructures of powders and of the processed bulk samples were studied and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and field emission gun scanning electron microscope (FEGSEM). Standard VSM measurements were processed for magnetic characterizations. Magnetic static measurements were performed at 10 K and 300 K showing that magnetic properties of nanostructured cobalt bulk systems can be tuned from hard to soft just changing the shape of nano-systems used for compaction and/or the sintering conditions. Also the mechanical properties show a strong dependence on the relative bulk densities and on the characteristics of grain inside the consolidated samples. Preliminary results show that nanostructured cobalt obtained from nanowires compaction present higher Vickers Hardness value.

Processing-structure-properties relationships in PLA nanocomposite films

Science.gov (United States)

Di Maio, L.; Scarfato, P.; Garofalo, E.; Galdi, M. R.; D'Arienzo, L.; Incarnato, L.

2014-05-01

This work deals on the possibility to improve performances of PLA-based nanocomposite films, for packaging applications, through conveniently tuning materials and processing conditions in melt compounding technology. In particular, two types of polylactic acid and different types of filler selected from montmorillonites and bentonites families were used to prepare the hybrid systems by using a twin-screw extruder. The effect of biaxial drawing on morphology and properties of the nanocomposites, produced by film blowing, was investigated.

Identification of parametric models with a priori knowledge of process properties

Directory of Open Access Journals (Sweden)

Janiszowski Krzysztof B.

2016-12-01

Full Text Available An approach to estimation of a parametric discrete-time model of a process in the case of some a priori knowledge of the investigated process properties is presented. The knowledge of plant properties is introduced in the form of linear bounds, which can be determined for the coefficient vector of the parametric model studied. The approach yields special biased estimation of model coefficients that preserves demanded properties. A formula for estimation of the model coefficients is derived and combined with a recursive scheme determined for minimization of the sum of absolute model errors. The estimation problem of a model with known static gains of inputs is discussed and proper formulas are derived. This approach can overcome the non-identifiability problem which has been observed during estimation based on measurements recorded in industrial closed-loop control systems. The application of the proposed approach to estimation of a model for an industrial plant (a water injector into the steam flow in a power plant is presented and discussed.

Guar gum: processing, properties and food applications-A Review.

Science.gov (United States)

Mudgil, Deepak; Barak, Sheweta; Khatkar, Bhupendar Singh

2014-03-01

Guar gum is a novel agrochemical processed from endosperm of cluster bean. It is largely used in the form of guar gum powder as an additive in food, pharmaceuticals, paper, textile, explosive, oil well drilling and cosmetics industry. Industrial applications of guar gum are possible because of its ability to form hydrogen bonding with water molecule. Thus, it is chiefly used as thickener and stabilizer. It is also beneficial in the control of many health problems like diabetes, bowel movements, heart disease and colon cancer. This article focuses on production, processing, composition, properties, food applications and health benefits of guar gum.

The Characteristics of Electrical and Physical Properties of Peat Soil in Rasau Village, West Kalimantan

Science.gov (United States)

Aminudin, A.; Hasanah, T. R.; Iryati, M.

2018-05-01

The Electrical and physical properties can be used as indicators for measuring soil conditions. One of the methods developed in agricultural systems to obtain information on soil conditions is through measuring of electrical conductivity. Peat soil is one of the natural resources that exist in Indonesia. This study aims to determine the characteristics of peat soil in Rasau village, West Kalimantan. This research was conducted by the properties of electrical conductivity and water content using 5TE Water Contents and EC Sensor equipment, but also to know the change of physical nature of peat soil covering peat soil and peat type. The results showed that the electrical conductivity value of 1-4 samples was 0.02 -0.29 dS/m and the volume water content value (VWC) was 0.255-0.548 m3/m3 and the physical characteristics obtained were peat colour brown to dark brown that allegedly the soil still has a very high content of organic material derived from weathering plants and there are discovery of wood chips, wood powder and leaf powder on the ground. Knowing the information is expected to identify the land needs to be developed to be considered for future peat soil utilization.

[Establishment and practice of traditional Chinese medicine property cognitive model based on three elements].

Science.gov (United States)

Zhang, Bing; Jin, Rui; Huang, Jianmei; Liu, Xiaoqing; Xue, Chunmiao; Lin, Zhijian

2012-08-01

Traditional Chinese medicine (TCM) property theory is believed to be a key and difficult point of basic theory studies of TCM. Complex concepts, components and characteristics of TCM property have long puzzled researchers and urged them to develop new angles and approaches. In the view of cognitive science, TCM property theory is a cognitive process of storing, extracting, rebuilding and summarizing the sensory information about TCMs and their effects during the medical practice struggling against diseases under the guidance of traditional Chinese philosophical thinking. The cognitive process of TCM property has particular cognitive elements and strategies. Taking into account clinical application characteristics of TCMs, this study defines the particular cognitive elements. In the combination of research methods of modern chemistry, biology and mathematics, and on the basis early-stage work for five years, we have built a TCM property cognition model based on three elements and practiced with drugs with pungent and hot properties as example, in the hope of interpreting TCM properties with modern science and providing thoughts for the nature of medical properties and instruction for rational clinical prescription.

Resistive switching characteristics of solution-processed Al-Zn-Sn-O films annealed by microwave irradiation

Science.gov (United States)

Kim, Tae-Wan; Baek, Il-Jin; Cho, Won-Ju

2018-02-01

In this study, we employed microwave irradiation (MWI) at low temperature in the fabrication of solution-processed AlZnSnO (AZTO) resistive random access memory (ReRAM) devices with a structure of Ti/AZTO/Pt and compared the memory characteristics with the conventional thermal annealing (CTA) process. Typical bipolar resistance switching (BRS) behavior was observed in AZTO ReRAM devices treated with as-deposited (as-dep), CTA and MWI. In the low resistance state, the Ohmic conduction mechanism describes the dominant conduction of these devices. On the other hand, the trap-controlled space charge limited conduction (SCLC) mechanism predominates in the high resistance state. The AZTO ReRAM devices processed with MWI showed larger memory windows, uniform distribution of resistance state and operating voltage, stable DC durability (>103 cycles) and stable retention characteristics (>104 s). In addition, the AZTO ReRAM devices treated with MWI exhibited multistage storage characteristics by modulating the amplitude of the reset bias, and eight distinct resistance levels were obtained with stable retention capability.

Insights into the IASB due process: the influence of country characteristics on constituents’ formal participation

Directory of Open Access Journals (Sweden)

Karsten Eisenschmidt

2017-12-01

Full Text Available The paper explores the impact of country characteristics on constituents’ formal participation in the IASB’s due process. We hypothesize that there is an association between the level of constituents’ partic- ipation and (1 the level of economic development, and (2 the cultural characteristics of the country of origin. We use a number of comment letters (CLs and their length as proxies for constituents’ formal participation in the IASB’s due process. The results indicate that economic development (equity market capitalization is the most important explanatory factor for the different levels of participation. In con- trast, the cultural characteristics measured by Hofstede’s cultural framework can only partially explain that differences. Only individualism is a significant positive influence factor for the level of constituents’ participation. The results of our descriptive analysis for the CLs and the information input provided show that there is still a lack of participation in the IASB’s due process. Despite the huge impact of accounting norms on societies, only a limited number of constituents participate, and some constituent groups, like users or academics, participate less.

Insight in bipolar disorder : associations with cognitive and emotional processing and illness characteristics

NARCIS (Netherlands)

van der Werf - Eldering, Marieke; van der Meer, Lisette; Burger, Huibert; Holthausen, Esther; Nolen, W.A.; Aleman, Andre

Objective: To investigate the multifactorial relationship between illness insight, cognitive and emotional processes, and illness characteristics in bipolar disorder patients. Methods: Data from 85 euthymic or mildly to moderately depressed bipolar disorder patients were evaluated. Insight was

Characteristic functions of inclusive processes with participation of light nuclei

International Nuclear Information System (INIS)

Omboo, Z.; Pak, A.S.; Saakyan, S.B.; Tarasov, A.V.; Uzhinskij, V.V.

1981-01-01

The problem of calculation of impulse spectra in the pA→pX reaction with participation of light nuclei is considered. Explicit expression for characteristic functions of inclusive processes taking into account the centre of mass correlations of a target-nucleus are obtained. It is assumed that the ground state of target-nucleus is described by the wave function of harmonic oscillator ground state which depend on Jacobi relative coordinates, and the final state is described by the plane wave system [ru

Optimization of pulsed TIG welding process parameters on mechanical properties of AA 5456 Aluminum alloy weldments

Energy Technology Data Exchange (ETDEWEB)

Kumar, A. [Department of Mechanical Engineering, National Institute of Technology, Warangal 506 004 (India)], E-mail: adepu_kumar7@yahoo.co.in; Sundarrajan, S. [Scientist ' G' , Defence Research and Development Laboratory, Hyderabad 500 028 (India)

2009-04-15

The present work pertains to the improvement of mechanical properties of AA 5456 Aluminum alloy welds through pulsed tungsten inert gas (TIG) welding process. Taguchi method was employed to optimize the pulsed TIG welding process parameters of AA 5456 Aluminum alloy welds for increasing the mechanical properties. Regression models were developed. Analysis of variance was employed to check the adequacy of the developed models. The effect of planishing on mechanical properties was also studied and observed that there was improvement in mechanical properties. Microstructures of all the welds were studied and correlated with the mechanical properties.

Optimization of pulsed TIG welding process parameters on mechanical properties of AA 5456 Aluminum alloy weldments

International Nuclear Information System (INIS)

Kumar, A.; Sundarrajan, S.

2009-01-01

The present work pertains to the improvement of mechanical properties of AA 5456 Aluminum alloy welds through pulsed tungsten inert gas (TIG) welding process. Taguchi method was employed to optimize the pulsed TIG welding process parameters of AA 5456 Aluminum alloy welds for increasing the mechanical properties. Regression models were developed. Analysis of variance was employed to check the adequacy of the developed models. The effect of planishing on mechanical properties was also studied and observed that there was improvement in mechanical properties. Microstructures of all the welds were studied and correlated with the mechanical properties

Process and magnetic properties of cold pressed Ne Fe B bonded magnets

International Nuclear Information System (INIS)

Rodrigues, DAniel; Concilio, Gilberto Vicente; Landgraf, Fernando Jose Gomes; Zanchetta, Antonio Carlos

1996-01-01

Bonded magnets are polymer composites based on a mixture of a hard magnetic powder and a polymer. This mixture is processed as a traditional powder metallurgy material, cold pressed, or like a thermoplastic material, by injection molding. The polymeric phase to a large extent determines the mechanical properties of the composite, while magnetic powder determines its magnetic properties. They are less expensive and easier to produce, specially in the case of high complexity parts. This paper presents the relationship between process variables and magnetic properties of cold pressed Nd Fe B bonded magnets produced from melt spun flakes mixed with thermosetting resins. The experiments were done using Statistical Design of Experiments. The variables investigates were: uniaxial compaction pressure, binder type; binder content; size of Nd Fe B particles; addition of lubricant; and addition of small quantities of magnetic additives, particles of ferrites, iron, or alnico. (author)

Physicochemical Properties of Fungal Detoxified Cassava Mash and ...

African Journals Online (AJOL)

The physicochemical properties of fungal detoxified cassava mash and sensory characteristics of wheat-detoxified cassava composite doughnuts were investigated. Fungal isolates from soils collected at cassava processing sites were isolated, quantified and identified. Cassava mash from grated tuber was partially ...

Sensitometric characteristics of D-, E- and F-speed dental radiographic films in manual and automatic processing

Directory of Open Access Journals (Sweden)

Jahangir Haghani DDS, MSc

2012-09-01

Full Text Available BACKGROUND AND AIM:The purpose of this study was to evaluatethe sensitometric characteristics of Ultraspeed,Ektaspeed Plus and Insight dental radiographic films using manual and automatic processing systems.METHODS:In this experimental invitro study, an aluminum step-wedge was used to construct characteristic curves forD-, E- and F-speed radiographic films (Kodak Eastman, Rochester, USA. All films were processed in Iranianprocessing solution (chemical industries Co., Iran, Tehran both manually and automatically in a period of six days.Unexposed films of three types were processed manually andautomatically to determine base plus fog density. Speedand film contrast were measured according to International Standard Organization definition.RESULTS:There was significant difference in density obtained with the D-, E- and F-speed films in both manually andautomatically processing systems (P < 0.001. There was significant difference in density obtained with the Ultraspeed andinsight films. There was no significant difference in contrast obtained with the D-, E- and F-speed films in both manuallyand automatically processing systems (P = 0.255 , P = 0.260. There was significant difference in speed obtained with theD-, E- and F-speed films in both manually and automatically processing systems (P = 0.034, P = 0.040.CONCLUSIONS:The choice of processing system canaffect radiographic characteristics. The F-speed film processed inautomatic system has greater speed in comparison with manualprocessing system, and it provides a further reduction inradiation exposure without detriment to image quality.

Experimental investigation on the effect of process environment on the mechanical properties of AA5083/Al2O3 nanocomposite fabricated via friction stir processing

International Nuclear Information System (INIS)

Ashjari, M.; Mostafapour Asl, A.; Rouhi, S.

2015-01-01

Friction stir processing, a lately devised grain refining and also microstructure homogenizing technique, has extensively been used on aluminum alloys. Significance of limiting the grain growth during the process, has made lots of researchers make endeavor to keep, as one of the ways of controlling grain growth, the process temperature low; one way of doing so, is performing the friction stir process under water, which keeps the peak temperature low and increases the cooling rate as well. In the present work, research has been done to make known the effects of doing submerged friction stir processing on mechanical properties of AA5083/Al 2 O 3p composite. The process was completed on each sample without changing the rotation and traverse speed of the tool. The pin of the tool was a threaded cylindrical one. Tensile and micro-hardness tests were used to evaluate the effect of the process on these properties of the samples. Also to study the microstructure of the samples, optical microscopy (OM) and scanning electron microscopy (SEM) micrographs were used. The results show that, underwater friction stir process is capable of producing defect-free AA5083/Al 2 O 3p nanocomposite. Analyzing the properties of the processed samples showed that, by significantly reducing the grain size, water environment has positive impact on the mechanical properties of the alloy; And that, Hall–Petch effect is more powerful than Orowan mechanism in enhancing the mechanical properties of the samples

Application of the chemical properties of ruthenium to decontamination processes

International Nuclear Information System (INIS)

Fontaine, A.; Berger, D.

1965-01-01

The chemical properties of ruthenium in the form of an aqueous solution of the nitrate and of organic tributylphosphate solution are reviewed. From this data, some known examples are given: they demonstrate the processes of separation or of elimination of ruthenium from radioactive waste. (authors) [fr

Building Process and Architectural Planning Characteristics of Daehan Hospital Main Building

Directory of Open Access Journals (Sweden)

Geauchul LEE

2016-04-01

Full Text Available This paper explores the introduction process of Daehan Hospital from Japan as the modern medical facility in Korea, and the architectural planning characteristics as a medical facility through the detailed building process of Daehan Hospital main building. The most noticeable characteristic of Daehan Hospital is that it was designed and constructed not by Korean engineers but by Japanese engineers. Therefore, Daehan Hospital was influenced by Japanese early modern medical facility, and Japanese engineers modeled Daehan Hospital main building on Tokyo Medical School main building which was constructed in 1876 as the first national medical school and hospital. The architectural type of Tokyo Medical School main building was a typical school architecture in early Japanese modern period which had a middle corridor and a pseudo Western-style tower, but Tokyo Medical School main building became the model of a medical facility as the symbol of the medical department in Tokyo Imperial University. This was the introduction and transplantation process of Japanese modern ‘model’ like as other modern systems and technologies during the Korean modern transition period. However, unlike Tokyo Medical School main building, Daehan Hospital main building was constructed not as a wooden building but as a masonry building. Comparing with the function of Daehan Hospital main building, its architectural form and construction costs was excessive scale, which was because Japanese Resident-General of Korea had the intention of ostentation that Japanese modernity was superior to Korean Empire.

[Building Process and Architectural Planning Characteristics of Daehan Hospital Main Building].

Science.gov (United States)

Lee, Geauchul

2016-04-01

This paper explores the introduction process of Daehan Hospital from Japan as the modern medical facility in Korea, and the architectural planning characteristics as a medical facility through the detailed building process of Daehan Hospital main building. The most noticeable characteristic of Daehan Hospital is that it was designed and constructed not by Korean engineers but by Japanese engineers. Therefore, Daehan Hospital was influenced by Japanese early modern medical facility, and Japanese engineers modeled Daehan Hospital main building on Tokyo Medical School main building which was constructed in 1876 as the first national medical school and hospital. The architectural type of Tokyo Medical School main building was a typical school architecture in early Japanese modern period which had a middle corridor and a pseudo Western-style tower, but Tokyo Medical School main building became the model of a medical facility as the symbol of the medical department in Tokyo Imperial University. This was the introduction and transplantation process of Japanese modern 'model' like as other modern systems and technologies during the Korean modern transition period. However, unlike Tokyo Medical School main building, Daehan Hospital main building was constructed not as a wooden building but as a masonry building. Comparing with the function of Daehan Hospital main building, its architectural form and construction costs was excessive scale, which was because Japanese Resident-General of Korea had the intention of ostentation that Japanese modernity was superior to Korean Empire.

Molecular and Thermodynamic Properties of Zwitterions versus Ionic Liquids: A Comprehensive Computational Analysis to Develop Advanced Separation Processes.

Science.gov (United States)

Moreno, Daniel; Gonzalez-Miquel, Maria; Ferro, Victor R; Palomar, Jose

2018-04-05

Zwitterion ionic liquids (ZIs) are compounds in which both counterions are covalently tethered, conferring them with unique characteristics; however, most of their properties are still unknown, representing a bottleneck to exploit their practical applications. Herein, the molecular and fluid properties of ZIs and their mixtures were explored by means of quantum chemical analysis based on the density functional theory (DFT) and COSMO-RS method, and compared against homologous ionic liquids (ILs) to provide a comprehensive overview of the effect of the distinct structures on their physicochemical and thermodynamic behavior. Overall, ZIs were revealed as compounds with higher polarity and stronger hydrogen-bonding capacity, implying higher density, viscosity, melting point, and even lower volatility than structurally similar ILs. The phase equilibrium of binary and ternary systems supports stronger attractive interactions between ZIs and polar compounds, whereas higher liquid-liquid immiscibility with nonpolar compounds may be expected. Ultimately, the performance of ZIs in the wider context of separation processes is illustrated, while providing molecular insights to allow their selection and design for relevant applications. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Properties of plutonium

International Nuclear Information System (INIS)

Ahn, Jin Su; Yoon, Hwan Ki; Min, Kyung Sik; Kim, Hyun Tae; Ahn, Jong Sung; Kwag, Eon Ho; Ryu, Keon Joong

1996-03-01

Plutonium has unique chemical and physical properties. Its uniqueness in use has led to rare publications, in Korea. This report covers physical aspects of phase change of metal plutonium, mechanical properties, thermal conductivity, etc, chemical aspects of corrosion, oxidation, how to produce plutonium from spent fuels by describing various chemical treatment methods, which are currently used and were used in the past. It also contains characteristics of the purex reprocessing process which is the most widely used nowadays. And show processes to purify and metalize from recovered plutonium solution. Detection and analysis methods are introduced with key pints for handling, critical safety, toxicity, and effects on peoples. This report gives not only a general idea on what plutonium is, rather than deep technical description, but also basic knowledge on plutonium production and safeguards diversion from the view point of nonproliferation. 18 refs. (Author) .new

Properties of plutonium

Energy Technology Data Exchange (ETDEWEB)

Ahn, Jin Su; Yoon, Hwan Ki; Min, Kyung Sik; Kim, Hyun Tae; Ahn, Jong Sung; Kwag, Eon Ho; Ryu, Keon Joong [Korea Atomic Energy Research Institute, Daeduk (Korea, Republic of)

1996-03-01

Plutonium has unique chemical and physical properties. Its uniqueness in use has led to rare publications, in Korea. This report covers physical aspects of phase change of metal plutonium, mechanical properties, thermal conductivity, etc, chemical aspects of corrosion, oxidation, how to produce plutonium from spent fuels by describing various chemical treatment methods, which are currently used and were used in the past. It also contains characteristics of the purex reprocessing process which is the most widely used nowadays. And show processes to purify and metalize from recovered plutonium solution. Detection and analysis methods are introduced with key pints for handling, critical safety, toxicity, and effects on peoples. This report gives not only a general idea on what plutonium is, rather than deep technical description, but also basic knowledge on plutonium production and safeguards diversion from the view point of nonproliferation. 18 refs. (Author) .new.

Determining firm characteristics and the level of voluntary corporate governance disclosures among Malaysian listed property companies

Directory of Open Access Journals (Sweden)

Talpur Shabana

2018-01-01

Full Text Available This study examined the level of voluntary corporate governance disclosures and the influence of firm characteristics (i.e., firm size, firm age, and firm market listing on the level of these disclosures among Malaysian property listed companies. The check-list to measure the voluntary corporate governance disclosures was adopted from Malaysian corporate governance index 2011 by Minority Shareholder Watchdog Group (MSWG. The voluntary corporate governance disclosure practices and firm specific characteristics were obtained from annual reports of property listed companies on Bursa Malaysia for the period of 2012 to 2015. The findings suggested an improving voluntary corporate governance reforms in Malaysia. However, the firm size was found as an inflicting factor in determining the level and quality of voluntary corporate governance disclosure practices. On the contrary, the results found were contradicting the hypothesis related to firm age and firm market listing, as no relation of voluntary corporate governance disclosures and firm age and firm market listing. The study has made an interesting contribution toward the disclosure and corporate governance by contributing in understanding the importance of quality disclosure and good governance practices.

Study of optical characteristics of tin oxide thin film prepared by sol

Indian Academy of Sciences (India)

–gel process. The film was synthesized on a glass (Corning 7059) plate by dip coating method. Here, we used tin (II) chloride as precursor and methanol as solvent. Optical characteristics and physical properties like refractive index, absorption ...

The slag original from the process of sewage sludge incineration selected properties characteristic

Science.gov (United States)

Głowacka, Anna; Rucińska, Teresa; Kiper, Justyna

2017-11-01

This work characterizes the physical and chemical properties of slag from combustion of municipal sewage sludge in "Pomorzany" waste treatment plant in Szczecin. The technology of sludge management is based on drying the sludge in low-temperature belt driers, to a content level of at least 90%, dry mass., and then burning in a grate boiler with mobile grate. The research of the slag resulting from combustion of municipal sewage sludge was conducted using reference methods, presenting images from a scanning electron microscope. The tested waste contained from 16.300 to 23.150% P2O5 completely soluble in strong acids, pH 8.03, mineral substance 98.73% dry mass. The content of heavy metals did not exceed the permissible amount specified in the Regulation of the Minister of Agriculture and Rural Development of 18 June 2008 on the implementation of certain provisions of the Act on fertilizers and fertilization (Journal of Laws of 2008 No. 119, item. 765). The screening trials showed that 48.4% are fractions of 630 µm-1.25 mm. The results show that the waste code 19 01 12 may be used as: alternative source of phosphorus for direct application to soil treatment, for production of organic - mineral fertilizers and as construction aggregate for production of concrete mortars.

Processing and impact properties of steel based laminated composites

International Nuclear Information System (INIS)

Carreno, F.; Pozuelo, M.; Chao, J.; Ruano, O. A.

2001-01-01

A seven layers steel based laminated composite (four ultra-high carbon steel, UHCS, layers and three mild steel, MS layers) has been processed by rolling bonding and its microstructure and impact properties have been studied. Suitable parameters of temperature and thickness reduction were selected to obtain a finer microstructure relative to the original materials components. This finer microstructure induces improved mechanical properties. Charpy impact tests values in both crack arrester and crack divider orientations improve the values of the UHCS constituent materials. Furthermore, the crack arrester orientation value exceed that of the MS material. The delamination, which is controlled by interface bonding, plays a key role defecting the crack, absorbing energy and imposing the nucleation of new cracks in the next materials layers. (Author) 10 refs

Effects of tunnel oxide process on SONOS flash memory characteristics

International Nuclear Information System (INIS)

Li, Dong Hua; Park, Il Han; Yun, Jang-Gn; Park, Byung-Gook

2010-01-01

In this paper, various process conditions of tunnel oxides are applied in SONOS flash memory to investigate their effects on charge transport during the program/erase operations. We focus the key point of analysis on Fermi-level (E F ) variation at the interface of silicon substrate and tunnel oxide. The Si-O chemical bonding information which describes the interface oxidation states at the Si/SiO 2 is obtained by the core-level X-ray photoelectron spectroscopy (XPS). Moreover, relative E F position is determined by measuring the Si 2p energy shift from XPS spectrums. Experimental results from memory characteristic measurement show that MTO tunnel oxide structure exhibits faster erase speed, and larger memory window during P/E cycle compared to FTO and RTO tunnel oxide structures. Finally, we examine long-term charge retention characteristic and find that the memory windows of all the capacitors remain wider than 2 V after 10 5 s.

Medium Modifications of Hadron Properties and Partonic Processes

Energy Technology Data Exchange (ETDEWEB)

Brooks, W. K.; Strauch, S.; Tsushima, K.

2011-06-01

Chiral symmetry is one of the most fundamental symmetries in QCD. It is closely connected to hadron properties in the nuclear medium via the reduction of the quark condensate , manifesting the partial restoration of chiral symmetry. To better understand this important issue, a number of Jefferson Lab experiments over the past decade have focused on understanding properties of mesons and nucleons in the nuclear medium, often benefiting from the high polarization and luminosity of the CEBAF accelerator. In particular, a novel, accurate, polarization transfer measurement technique revealed for the first time a strong indication that the bound proton electromagnetic form factors in 4He may be modified compared to those in the vacuum. Second, the photoproduction of vector mesons on various nuclei has been measured via their decay to e+e- to study possible in-medium effects on the properties of the rho meson. In this experiment, no significant mass shift and some broadening consistent with expected collisional broadening for the rho meson has been observed, providing tight constraints on model calculations. Finally, processes involving in-medium parton propagation have been studied. The medium modifications of the quark fragmentation functions have been extracted with much higher statistical accuracy than previously possible.

Engineering properties of high and low altitude rice varieties from Kashmir valley at different processing levels

Directory of Open Access Journals (Sweden)

Raees Haq

2016-12-01

Full Text Available The knowledge of engineering properties such as gravimetrical properties (1,000 grain mass, bulk density, true density, and porosity, dimensional properties (length, width, thickness, aspect ratio, surface area, geometric mean diameter, and sphericity, frictional properties (angle of repose and coefficient of friction, and aerodynamic properties (drag coefficient and terminal velocity are necessary parameters related to machine design for different agricultural process operations such as handling, harvesting, threshing, cleaning, conveying, sorting, drying, processing, and storage. India is a vast country and contributes 20% of the total world’s rice production with cultivars ranging from the scented long grain ones to the sticky short grains. The Kashmir valley cultivates mainly short–medium bold varieties as temperate conditions in the valley are not suitable for the cultivation of long grain scented basmati rice. The most steps in cultivation and postharvest processing are manual and the aim of this work is to emphasize which variety sustains the processing steps to produce high yield quality rice for strengthening the economic conditions of the people.

Improvement on the concentrated grape juice physico-chemical characteristics by an enzymatic treatment and Membrane Separation Processes

Directory of Open Access Journals (Sweden)

PLÍNIO R.F. CAMPOS

2016-03-01

Full Text Available ABSTRACT In this work, the improvement on the concentrated grape juice physico-chemical characteristics by using an enzymatic treatment followed by Membrane Separation Process (MSP has been investigated. By using Novozym 33095(r and Ultrazym AFP L(r enzymes varying three operating parameters, the best result on the grape pulp characteristics was attained for the Novozym 33095(r performed at 35oC, 15 min. and 50 mgL-1. In micro/ultra filtration processes after enzymatic pretreatment, the best performance of the MSP with high permeate flux value and suitable grape juice characteristics was attained using 0.05 mm membrane pore size, 1 bar pressure and 40 oC treatment temperature. When reverse osmosis process is operated at 40 bar and 40oC, high soluble solid and low turbidity values are attained. An enzymatic treatment along with MSP has shown an alternative and efficient grape juice processing system, being possible to extend to other foods.

Effects of the Seed Distance on the Characteristics of the (100)/(100) Junctions of Top-Seeded Melt Growth Processed YBCO Superconductors Using Two Seeds

Energy Technology Data Exchange (ETDEWEB)

Kim, C.J.; Gee, Y.A.; Hong, G.Y. [Korea Atomic Energy Research Institute, Taejon (Korea); Kim, H.J.; Joo, J.H. [Sungkyunkwan University, Suwon (Korea); Han, S.C.; Han, Y.H.; Sung, T.H.; Kim, S.J. [Korea Electric Power Research Institute, Taejon (Korea)

1999-06-01

The effects of the distance (d) between two Sm{sub 1.8}Ba{sub 2.4}Cu{sub 3.4}Ox seeds on the characteristics of the (100)/(100) junctions of top-seeded melt growth processed YBCO superconductors were investigated. The trapped magnetic field at the grain junction and the levitation force of the top surface decreased with increasing d value. The degradation of the properties is attributed to the presence of the residual melt-forming phases (CuO and BaCUO{sub 2}) at the grain junction, whose amount depends on the d value. (author). 18 refs., 10 figs.

Determining the thermal and physicals properties of oil processing products

Directory of Open Access Journals (Sweden)

Viktoria I. Kryvda

2015-03-01

Full Text Available In the last decades both technological process’ improvement and primary energy resources saving are the main tasks of oil refineries. Using various oil products does impose an accurate knowledge of their properties. The dispersion analysis applied makes possible to construct a model simulating the primary oil refining products’ and raw materials’ thermal physical properties. As a result of data approximation there were obtained polynomials with coefficients differing from attributable to the studied oil products fractions. The research represents graphic dependences of thermal physical properties on temperature values for diesel oil fraction. The linear character of density and calorific capacity dependencies from temperature is represented with a proportional error in calculations. The relative minimum error is below 2% that confirms the implemented calculations’ adequacy. The resulting model can be used in calculations for further technological process improvements.

Flame Spread and Damaged Properties of RCD Cases by Tracking

Science.gov (United States)

Choi, Chung-Seog; Kim, Hyang-Kon; Shong, Kil-Mok; Kim, Dong-Woo

In this paper, the flame spread and damaged properties of residual current protective devices (RCDs) by tracking were analyzed. Pictures of tracking process were taken by High Speed Imaging System (HSIS), and fire progression was observed by timeframe. During the tracking process of RCD, it seemed to explode just once in appearance, but in the results of HSIS analysis, a small fire broke out and disappeared repeatedly 35 times and a flash of light repeated 15 times. Finally, an explosion with a flash of light occurred and lots of particles were scattered. Electric muffle furnace was used for heat treatment of RCD cases. The surface characteristics of specimens due to heat treatment and tracking deterioration were taken by Scanning Electron Microscope (SEM). Chemical and thermal properties of these deteriorated specimens were analyzed by Fourier Transform Infrared Spectrometer (FT-IR) and Differential Thermal Analyzer (DTA). The carbonization characteristics showed different chemical properties due to energy sources, and the results could be applicable to judge the accident causes.

Dimensional and material characteristics of direct deposited tool steel by CO II laser

Science.gov (United States)

Choi, J.

2006-01-01

Laser aided direct metalimaterial deposition (DMD) process builds metallic parts layer-by-layer directly from the CAD representation. In general, the process uses powdered metaUmaterials fed into a melt pool, creating fully dense parts. Success of this technology in the die and tool industry depends on the parts quality to be achieved. To obtain designed geometric dimensions and material properties, delicate control of the parameters such as laser power, spot diameter, traverse speed and powder mass flow rate is critical. In this paper, the dimensional and material characteristics of directed deposited H13 tool steel by CO II laser are investigated for the DMD process with a feedback height control system. The relationships between DMD process variables and the product characteristics are analyzed using statistical techniques. The performance of the DMD process is examined with the material characteristics of hardness, porosity, microstructure, and composition.

THE INFLUENCE OF FATLIQOURING PROCESS ON PROTECTIVE CHARACTERISTICS OF LEATHER GLOVES

Directory of Open Access Journals (Sweden)

KILIÇ Eylem

2017-05-01

Full Text Available Appropriate protective gloves are essential for industry workers to avoid hands and wrists injuries. Leather is a common material used by professionals for technical gloves. Mechanical resistance, protection against water and high temperature has to be fulfilled by leather that is intended for using in protective gloves. In this study recipes using various fatliquoring agents with different properties such as lesitin based, lanolin based, polymeric based and water proofing fat liquor were applied to produce technical glove leather and effect of each fatliquoring product on protective performance of leathers were analyzed in terms of physical and mechanical properties including tensile (ISO 3376, stitch tear (ISO 23910, tear resistance (ISO 3377-2, static (ISO 2417 and dynamicwater absorption (ISO 5403-1 and thermal stability such as dry heat (ISO 17227 and heat stability (ISO 11645. For this purpose, chromium tanned split calf leathers were used and retanning of protective leather gloves were performed by using tara and phosphonium combination. Performance testing results obtained from four different retanning processes was compared according to the type of fatliquoring material used in the production. Post-tanning with different types of fatliquoring products have significant effect on the protective performance properties of leather gloves, in terms of mechanical and thermal properties.

Properties and behavior of quartz for the silicon process

Energy Technology Data Exchange (ETDEWEB)

Aasly, Kurt

2008-07-01

This PhD-thesis is a result of the study on important properties of quartz as a raw material for the metallurgical production of ferrosilicon and silicon metal. This includes defining mechanical properties important for the size reduction experienced during transport and storage and thermo-mechanical properties of quartz that is important for how the quartz reacts to the high temperatures experienced as it is charged on the furnace. Additionally, softening properties of quartz have been briefly discussed in some of the papers. Another important goal has been to test analytical and experimental methods for investigating the various properties. The investigations of important factors for the mechanical properties of ores and industrial minerals have been carried out as a literature study. The mining operation and transport from mine to smelter has been discussed and several factors that are significant for achieving best possible mechanical properties of the quartz have been identified. The most important factors are related to production in the mine and processing plant, which should be carefully planned to minimize the amount of blast-induced damage in the rock and thus achieve the best possible mechanical strength of the raw material. The amount of fines can be minimized by controlling the handling of the raw materials during the transport and storage. It is especially important to avoid high drops, both high single drops and accumulated height of all the drops in total. Investigations of the thermo-mechanical properties of quartz have been carried out by using different experimental and characterization methods. The petrographic investigations of the raw materials by polarized light microscopy have been important. Thermo-mechanical investigations have been high-temperature microthermometry and shock heating of quartz samples in an induction furnace with subsequent investigations of the heated material. The subsequent investigation included polarized- and

Control properties of hybrid distillation processes for the separation of biobutanol

DEFF Research Database (Denmark)

Sánchez-Ramírez, Eduardo; Alcocer-García, Heriberto; Quiroz-Ramírez, Juan José

2017-01-01

value decomposition technique and a closed-loop dynamic analysis was performed on several hybrid distillation processes including conventional, thermally coupled, thermodynamically equivalent and intensified designs. The results indicated that under the closed-loop control policy, an intensified design...... which is integrated for only two distillation columns instead of three distillation columns, showed good dynamic properties. In addition, thermally coupled sequence A showed better control properties under open-loop analysis. CONCLUSIONS: Using both SVD analysis and closed-loop tests the dynamics...

Firing: the proof test for ceramic processing

International Nuclear Information System (INIS)

Kingery, W.D.

1975-01-01

The object of ceramic processing is to form ware having certain shapes and properties. Thus, one test of the success of processing procedures must be in terms of the resulting structure and characteristics of a material after firing. During the firing process some few variations resulting from processing may be evened out, but the great majority of variation tends to be amplified. Examination of a few cases illustrates the nature of the defect amplification process. (U.S.)

Effects of uniquely processed cowpea and plantain flours on wheat bread properties

Science.gov (United States)

The effect of incorporating uniquely processed whole-seed cowpeas or plantain flours at 10 or 20 g/100 g in all-purpose flour on paste viscosity and bread-baking properties in model bread was determined. Flours from plantains processed as follows: unblanched plantains dried at 60 degrees C (PLC), so...

Core characteristics of fast reactor cycle with simple dry pyrochemical processing

International Nuclear Information System (INIS)

Ikegami, Tetsuo

2008-01-01

Fast reactor core concept and core nuclear characteristics are studied for the application of the simple dry pyrochemical processing for fast reactor mixed oxide spent fuels, that is, the Compound Process Fuel Cycle, large FR core with of loaded fuels are recycled by the simple dry pyrochemical processing. Results of the core nuclear analyses show that it is possible to recycle FR spent fuel once and to have 1.01 of breeding ratio without radial blanket region. The comparison is made among three kinds of recycle fuels, LWR UO 2 spent fuel, LWR MOX spent fuel, and FR spent fuel. The recycle fuels reach an equilibrium state after recycles regardless of their starting heavy metal compositions, and the recycled FR fuel has the lowest radio-activity and the same level of heat generation among the recycle fuels. Therefore, the compound process fuel cycle has flexibility to recycle both LWR spent fuel and FR spent fuel. The concept has a possibility of enhancement of nuclear non-proliferation and process simplification of fuel cycle. (author)

Characteristics of Friction Stir Processed UHMW Polyethylene Based Composite

Science.gov (United States)

Hussain, G.; Khan, I.

2018-01-01

Ultra-high molecular weight polyethylene (UHMWPE) based composites are widely used in biomedical and food industries because of their biocompatibility and enhanced properties. The aim of this study was to fabricate UHMWPE / nHA composite through heat assisted Friction Stir Processing. The rotational speed (ω), feed rate (f), volume fraction of nHA (v) and shoulder temperature (T) were selected as the process parameters. Macroscopic and microscopic analysis revealed that these parameters have significant effects on the distribution of reinforcing material, defects formation and material mixing. Defects were observed especially at low levels of (ω, T) and high levels of (f, v). Low level of v with medium levels of other parameters resulted in better mixing and minimum defects. A 10% increase in strength with only 1% reduction in Percent Elongation was observed at the above set of conditions. Moreover, the resulted hardness of the composite was higher than that of the parent material.

Papermaking Properties of Carpinus betulus with kraft, Soda and Soda-Urea Pulping Processes

Directory of Open Access Journals (Sweden)

Rasoul Darstan

2013-06-01

Full Text Available This research was carried out in order to comparatively investigate the hornbeam kraft, soda and soda-urea papermaking properties. The selected treatment in kraft process had an average yield of 44.43% and kappa number of 23.75. In soda process the selected treatment had an average yield of 38.75% and kappa number of 19.28. In soda-urea process, the selected treatments had an average yield of 39.85, 40.1, 40.5, 39.8 and 40.61 and kappa number of 21.21, 22.33, 22.66, 25.28 and 26.85. After refining the selected pulp to reach the freeness of 400±25 ml CSF, 60 g/m2 handsheets were made and physical, mechanical and optical properties were measured. Results showed that kraft pulps had higher yield and better refinability than soda and soda-urea pulps. Papers made from kraft process had higher strength properties than those made of soda and soda-urea process. With addition of urea, yield and kappa number of pulps increased. The highest improvement in tensile index, breaking length and tear index was achieved with addition of 3% urea and the highest improvement in burst index was achieved with adding 4% urea. Results of brightness measurements showed that papers from kraft and soda processes had the lowest and highest brightness degree respectively. With the addition of urea, brightness of papers decreased.

Effect of Cassava Processing Effluent on Soil Properties, Growth and ...

African Journals Online (AJOL)

A study, comprising a survey, greenhouse and field experiments was conducted to examine the effect of Cassava Processing Effluent (CPE) on soil chemical properties, maize growth performances and grain yield. In the survey, soil samples were taken (0-15 and 15 – 30cm) of CPE contaminated and non contaminated ...

Effect of annealing process of iron powder on magnetic properties ...

Indian Academy of Sciences (India)

Administrator

Abstract. Iron powder magnetic cores are used as soft magnetic rotors, in micro special motors such as BS brake motors, refrigerator compressor motors and brushless servo motors. Heat treatment of iron powder played an important role in the magnetic properties and loss of the motor cores. After the annealing process,.

The manufacture process and properties of (U, Gd)O2 burnable poisonous fuel pellets

International Nuclear Information System (INIS)

Yi Wei; Tang Yueming; Dai Shengping; Yang Youqing; Zuo Guoping; Wu Shihong; Gu Xiaofei; Gu Mingfei

2006-03-01

The main properties of important raw powder materials used in the (U, Gd)O 2 burnable poisonous fuel pellets production line of NPIC are presented. The powders included UO 2 , Gd 2 O 3 , (U, Gd) 3 O 8 and necessary additives, such as ammonium oxalate and zinc stearate. And the main properties of (U, Gd)O 2 burnable poisonous fuel pellets and the manufacture processes, such as ball-milling blending, granulation, pressing, sintering and grinding are also described. Moreover, the main effect of the process parameters controlled in the manufacture process have been discussed. (authors)

Investigation of the dielectric properties of shale

International Nuclear Information System (INIS)

Martemyanov, Sergey M.

2011-01-01

The article is dedicated to investigation of the dielectric properties of oil shale. Investigations for samples prepared from shale mined at the deposit in Jilin Province in China were done. The temperature and frequency dependences of rock characteristics needed to calculate the processes of their thermal processing are investigated. Frequency dependences for the relative dielectric constant and dissipation factor of rock in the frequency range from 0,1 Hz to 1 MHz are investigated. The temperature dependences for rock resistance, dielectric capacitance and dissipation factor in the temperature range from 20 to 600°C are studied. Key words: shale, dielectric properties, relative dielectric constant, dissipation factor, temperature dependence, frequency dependence

Influence of shielding gas pressure on welding characteristics in CO2 laser-MIG hybrid welding process

Science.gov (United States)

Chen, Yanbin; Lei, Zhenglong; Li, Liqun; Wu, Lin

2006-01-01

The droplet transfer behavior and weld characteristics have been investigated under different pressures of shielding gas in CO2 laser and metal inert/active gas (laser-MIG) hybrid welding process. The experimental results indicate that the inherent droplet transfer frequency and stable welding range of conventional MIG arc are changed due to the interaction between CO2 laser beam and MIG arc in laser-MIG hybrid welding process, and the shielding gas pressure has a crucial effect on welding characteristics. When the pressure of shielding gas is low in comparison with MIG welding, the frequency of droplet transfer decreases, and the droplet transfer becomes unstable in laser-MIG hybrid welding. So the penetration depth decreases, which shows the characteristic of unstable hybrid welding. However, when the pressure of shielding gas increases to a critical value, the hybrid welding characteristic is changed from unstable hybrid welding to stable hybrid welding, and the frequency of droplet transfer and the penetration depth increase significantly.

Process optimization and properties of magnetically hard cobalt carbide nanoparticles via modified polyol method

International Nuclear Information System (INIS)

Zamanpour, Mehdi; Bennett, Steven P.; Majidi, Leily; Chen, Yajie; Harris, Vincent G.

2015-01-01

Highlights: • High-coercivity cobalt carbides were synthesized by polyol method. • No rare earth elements were used during synthesis process. • Process parameters (reaction temperature, precursors’ concentrations, surfactants and reaction duration) were studied/optimized. • Process was scaled-up to synthesis more than 5 g powders per batch. - Abstract: Cobalt carbide magnetic nanoparticles were successfully synthesized via a modified polyol process without using a rare-earth catalyst during the synthesis process. The present results show admixtures of Co 2 C and Co 3 C phases possessing magnetization values exceeding 47 emu/g and coercivity values exceeding 2.3 kOe at room temperature. Moreover, these experiments have illuminated the important role of the reaction temperature, hydroxyl ion concentrations and the reaction duration on the crystallographic structure and magnetic properties of the nanoparticles. The crystallographic structure and particle size of the Co x C nanoparticles were characterized by X-ray diffractometry and scanning electron microscopy. Vibrating sample magnetometry was used to determine magnetic properties. Scale-up of synthesis to more than 5 g per batch was demonstrated with no significant degradation of magnetic properties

Process optimization and properties of magnetically hard cobalt carbide nanoparticles via modified polyol method

Energy Technology Data Exchange (ETDEWEB)

Zamanpour, Mehdi; Bennett, Steven P. [Center for Microwave Magnetic Materials and Integrated Circuits (CM3IC), Northeastern University, Boston, MA 02115 (United States); Majidi, Leily [Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA 02115 (United States); Chen, Yajie [Center for Microwave Magnetic Materials and Integrated Circuits (CM3IC), Northeastern University, Boston, MA 02115 (United States); Harris, Vincent G. [Center for Microwave Magnetic Materials and Integrated Circuits (CM3IC), Northeastern University, Boston, MA 02115 (United States); Department of Electrical and Computer Engineering, Northeastern University, Boston, MA 02115 (United States)

2015-03-15

Highlights: • High-coercivity cobalt carbides were synthesized by polyol method. • No rare earth elements were used during synthesis process. • Process parameters (reaction temperature, precursors’ concentrations, surfactants and reaction duration) were studied/optimized. • Process was scaled-up to synthesis more than 5 g powders per batch. - Abstract: Cobalt carbide magnetic nanoparticles were successfully synthesized via a modified polyol process without using a rare-earth catalyst during the synthesis process. The present results show admixtures of Co{sub 2}C and Co{sub 3}C phases possessing magnetization values exceeding 47 emu/g and coercivity values exceeding 2.3 kOe at room temperature. Moreover, these experiments have illuminated the important role of the reaction temperature, hydroxyl ion concentrations and the reaction duration on the crystallographic structure and magnetic properties of the nanoparticles. The crystallographic structure and particle size of the Co{sub x}C nanoparticles were characterized by X-ray diffractometry and scanning electron microscopy. Vibrating sample magnetometry was used to determine magnetic properties. Scale-up of synthesis to more than 5 g per batch was demonstrated with no significant degradation of magnetic properties.

Investigations regarding the lowering of specific intellectual property risks identified in the production process

Directory of Open Access Journals (Sweden)

Pakocs Ramona

2017-01-01

Full Text Available The main purpose of this research is to decrease the emergence of specific intellectual property risks within the production process as well as increasing risk management performance of IP by preventing them. In order to achieve this, previous studies regarding the main specific intellectual property risks from industrial companies were analyzed together with their managerial methods as well as the possibility of reducing their emergence. As a result of the research conducted were identified five types of intellectual property risks that have a high potential of emergence in the production process, namely: the risk of production of goods in violation of IP rights; the know-how, production knowledge and trade secret disclosure risk; the technological risk of unprotected utility models; the technological risk of unprotected integrated circuits topographies and finally the risk of product counterfeit. In order to achieve the main purpose of our investigation, we have proposed new formulas for estimating the specific intellectual property risks identified in the production process. Their purpose was to minimalize the risk’s negative effects on industrial companies and to increase the managerial performance from the intellectual property domain through a new type of management appropriately named: intellectual property management. The research is finalized with a case study regarding the lapse of rights of a patented invention. Based on a case analysis, it was proved that the exploitation of an invention without a contract represents a counterfeit.

Electromagnetic heating processes: analysis and simulations

OpenAIRE

Calay, Rajnish Kaur

1994-01-01

Electromagnetic heating (EMH) processes are being increasingly used in the industrial and domestic sectors, yet they receive relatively little attention in the thermal engineering domain. Time-temperature characteristics in EMH are qualitatively different from those in conventional heating techniques due to the additional parameters (viz dielectric properties of the material, size and shape of the product and process frequency). From a unified theory perspective, a multi-...

Microstructural Evolution and Mechanical Properties in Superlight Mg-Li Alloy Processed by High-Pressure Torsion

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Qian Su

2018-04-01

Full Text Available Microstructural evolution and mechanical properties of LZ91 Mg-Li alloy processed by high-pressure torsion (HPT at an ambient temperature were researched in this paper. The microstructure analysis demonstrated that significant grain refinement was achieved after HPT processing with an average grain size reducing from 30 μm (the as-received condition to approximately 230 nm through 10 turns. X-ray diffraction analysis revealed LZ91 alloy was consisted of α phase (hexagonal close-packed structure, hcp and β phase (body-centered cubic structure, bcc before and after HPT processing. The mean value of microhardness increased with the increasing number of HPT turns. This significantly increased hardness of specimens can be explained by Hall-Petch strengthening. Simultaneously, the distribution of microhardness along the specimens was different from other materials after HPT processing due to the different mechanical properties of two different phases. The mechanical properties of LZ91 alloy processed by HPT were assessed by the micro-tensile testing at 298, 373, 423, and 473 K. The results demonstrate that the ultra-fine grain LZ91 Mg-Li alloy exhibits excellent mechanical properties: tensile elongation is approximately 400% at 473 K with an initial strain rate of 1 × 10−2 s−1.

Data-driven multi-scale multi-physics models to derive process-structure-property relationships for additive manufacturing

Science.gov (United States)

Yan, Wentao; Lin, Stephen; Kafka, Orion L.; Lian, Yanping; Yu, Cheng; Liu, Zeliang; Yan, Jinhui; Wolff, Sarah; Wu, Hao; Ndip-Agbor, Ebot; Mozaffar, Mojtaba; Ehmann, Kornel; Cao, Jian; Wagner, Gregory J.; Liu, Wing Kam

2018-01-01

Additive manufacturing (AM) possesses appealing potential for manipulating material compositions, structures and properties in end-use products with arbitrary shapes without the need for specialized tooling. Since the physical process is difficult to experimentally measure, numerical modeling is a powerful tool to understand the underlying physical mechanisms. This paper presents our latest work in this regard based on comprehensive material modeling of process-structure-property relationships for AM materials. The numerous influencing factors that emerge from the AM process motivate the need for novel rapid design and optimization approaches. For this, we propose data-mining as an effective solution. Such methods—used in the process-structure, structure-properties and the design phase that connects them—would allow for a design loop for AM processing and materials. We hope this article will provide a road map to enable AM fundamental understanding for the monitoring and advanced diagnostics of AM processing.

Data-driven multi-scale multi-physics models to derive process-structure-property relationships for additive manufacturing

Science.gov (United States)

Yan, Wentao; Lin, Stephen; Kafka, Orion L.; Lian, Yanping; Yu, Cheng; Liu, Zeliang; Yan, Jinhui; Wolff, Sarah; Wu, Hao; Ndip-Agbor, Ebot; Mozaffar, Mojtaba; Ehmann, Kornel; Cao, Jian; Wagner, Gregory J.; Liu, Wing Kam

2018-05-01

Additive manufacturing (AM) possesses appealing potential for manipulating material compositions, structures and properties in end-use products with arbitrary shapes without the need for specialized tooling. Since the physical process is difficult to experimentally measure, numerical modeling is a powerful tool to understand the underlying physical mechanisms. This paper presents our latest work in this regard based on comprehensive material modeling of process-structure-property relationships for AM materials. The numerous influencing factors that emerge from the AM process motivate the need for novel rapid design and optimization approaches. For this, we propose data-mining as an effective solution. Such methods—used in the process-structure, structure-properties and the design phase that connects them—would allow for a design loop for AM processing and materials. We hope this article will provide a road map to enable AM fundamental understanding for the monitoring and advanced diagnostics of AM processing.

Vacuum drying of apples (cv. Golden Delicious): drying characteristics, thermodynamic properties, and mass transfer parameters

Science.gov (United States)

Nadi, Fatemeh; Tzempelikos, Dimitrios

2018-01-01

In this work, apples of cv. Golden Delicious were cut into slices that were 5 and 7 mm thick and then vacuum dried at 50, 60 and 70 °C and pressure of 0.02 bar. The thin layer model drying kinetics was studied, and mass transfer properties, specifically effective moisture diffusivity and convective mass transfer coefficient, were evaluated using the Fick's equation of diffusion. Also, thermodynamic parameters of the process, i.e. enthalpy (ΔH), entropy (ΔS) and Gibbs free energy (ΔG), were determined. Colour properties were evaluated as one of the important indicators of food quality and marketability. Determination of mass transfer parameters and thermodynamic properties of vacuum dried apple slices has not been discussed much in the literature. In conclusion, the Nadi's model fitted best the observed data that represent the drying process. Thermodynamic properties were determined based on the dependence of the drying constant of the Henderson and Pabis model on temperature, and it was concluded that the variation in drying kinetics depends on the energy contribution of the surrounding environment. The enthalpy and entropy diminished, while the Gibbs free energy increased with the increase of the temperature of drying; therefore, it was possible to verify that variation in the diffusion process in the apple during drying depends on energetic contributions of the environment. The obtained results showed that diffusivity increased for 69%, while the mass transfer coefficient increase was even higher, 75%, at the variation of temperature of 20 °C. The increase in the dimensionless Biot number was 20%.

Effect of processing conditions on the mechanical properties of polypropylene/bentonite nano composites

International Nuclear Information System (INIS)

Alves, Tatianny S.; Cipriano, Pamela B.; Lira, Vanize F.; Canedo, Eduardo L.; Carvalho, Laura H. de

2009-01-01

This work dealt with the effect of processing conditions on the properties of polypropylene/bentonite compounds, using natural clay and an organoclay prepared with hexadecyl trimethyl ammonium bromide. Compounds with 1% clay were prepared by melt compounding in a single-screw extruder and in a counter-rotating twin-screw extruder, and characterized x-ray diffraction; tensile and impact mechanical tests. X ray diffraction results on clays and compounds show that the surfactant was incorporated within the clay galleries and that intercalated nano composites were obtained with the organoclay processed in either the single or the twin-screw extruder. The data also indicated that, without the addition of a compatibilizer, no significant variation of mechanical properties was observed for the composites processed in either extruder. (author)

Morphological Influence of Solution-Processed Zinc Oxide Films on Electrical Characteristics of Thin-Film Transistors

Directory of Open Access Journals (Sweden)

Hyeonju Lee

2016-10-01

Full Text Available We report on the morphological influence of solution-processed zinc oxide (ZnO semiconductor films on the electrical characteristics of ZnO thin-film transistors (TFTs. Different film morphologies were produced by controlling the spin-coating condition of a precursor solution, and the ZnO films were analyzed using atomic force microscopy, X-ray diffraction, X-ray photoemission spectroscopy, and Hall measurement. It is shown that ZnO TFTs have a superior performance in terms of the threshold voltage and field-effect mobility, when ZnO crystallites are more densely packed in the film. This is attributed to lower electrical resistivity and higher Hall mobility in a densely packed ZnO film. In the results of consecutive TFT operations, a positive shift in the threshold voltage occurred irrespective of the film morphology, but the morphological influence on the variation in the field-effect mobility was evident. The field-effect mobility in TFTs having a densely packed ZnO film increased continuously during consecutive TFT operations, which is in contrast to the mobility decrease observed in the less packed case. An analysis of the field-effect conductivities ascribes these results to the difference in energetic traps, which originate from structural defects in the ZnO films. Consequently, the morphological influence of solution-processed ZnO films on the TFT performance can be understood through the packing property of ZnO crystallites.

Hot cracking characteristic of welding using Nd:YAG laser beam

International Nuclear Information System (INIS)

Ro, Kyoung Bo; Yoo, Young Tae; Oh, Yong Seak; Shin, Ho Jun; Kim, Ji Hwan

2003-01-01

The Nd:YAG laser process is known to have high speed and deep penetration capability to become one of the most advanced welding technologies. In spite of its good mechanical characteristics, SM45C carbon steel has a high carbon contents and suffers a limitation in the industrial application due to the poor welding properties. The major process parameters studied in the present laser welding experiment were position of focus, travel speed and laser power

Determining firm characteristics and the level of voluntary corporate governance disclosures among Malaysian listed property companies

OpenAIRE

Talpur Shabana; Lizam Mohd; Keerio Nazia

2018-01-01

This study examined the level of voluntary corporate governance disclosures and the influence of firm characteristics (i.e., firm size, firm age, and firm market listing) on the level of these disclosures among Malaysian property listed companies. The check-list to measure the voluntary corporate governance disclosures was adopted from Malaysian corporate governance index 2011 by Minority Shareholder Watchdog Group (MSWG). The voluntary corporate governance disclosure practices and firm speci...

Exploiting mAb structure characteristics for a directed QbD implementation in early process development.

Science.gov (United States)

Karlberg, Micael; von Stosch, Moritz; Glassey, Jarka

2018-03-07

In today's biopharmaceutical industries, the lead time to develop and produce a new monoclonal antibody takes years before it can be launched commercially. The reasons lie in the complexity of the monoclonal antibodies and the need for high product quality to ensure clinical safety which has a significant impact on the process development time. Frameworks such as quality by design are becoming widely used by the pharmaceutical industries as they introduce a systematic approach for building quality into the product. However, full implementation of quality by design has still not been achieved due to attrition mainly from limited risk assessment of product properties as well as the large number of process factors affecting product quality that needs to be investigated during the process development. This has introduced a need for better methods and tools that can be used for early risk assessment and predictions of critical product properties and process factors to enhance process development and reduce costs. In this review, we investigate how the quantitative structure-activity relationships framework can be applied to an existing process development framework such as quality by design in order to increase product understanding based on the protein structure of monoclonal antibodies. Compared to quality by design, where the effect of process parameters on the drug product are explored, quantitative structure-activity relationships gives a reversed perspective which investigates how the protein structure can affect the performance in different unit operations. This provides valuable information that can be used during the early process development of new drug products where limited process understanding is available. Thus, quantitative structure-activity relationships methodology is explored and explained in detail and we investigate the means of directly linking the structural properties of monoclonal antibodies to process data. The resulting information as a

Characteristics of wood ash and influence on soil properties and nutrient uptake: an overview.

Science.gov (United States)

Demeyer, A; Voundi Nkana, J C; Verloo, M G

2001-05-01

Wood industries and power plants generate enormous quantities of wood ash. Disposal in landfills has been for long a common method for removal. New regulations for conserving the environment have raised the costs of landfill disposal and added to the difficulties for acquiring new sites for disposal. Over a few decades a number of studies have been carried out on the utilization of wood ashes in agriculture and forestry as an alternative method for disposal. Because of their properties and their influence on soil chemistry the utilization of wood ashes is particularly suited for the fertility management of tropical acid soils and forest soils. This review principally focuses on ash from the wood industry and power plants and considers its physical, chemical and mineralogical characteristics, its effect on soil properties, on the availability of nutrient elements and on the growth and chemical composition of crops and trees, as well as its impact on the environment.

Micro- and Nano-fibers by Electrospinning Technology: Processing, Properties, and Applications