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Plastic waste disposal is among the most challenging problems of the current era. Therefore, new methods and applications for the utilization of waste plastics are increasingly needed. To find them, it is essential to research and develop the material properties of recycled plastics. The effect of different ultraviolet light (UV) stabilizers on the color stability, melt properties and tensile properties of mixed waste plastics blends was studied in this paper. The mixed waste plastics collected from two different waste sources were prepared as specimens by injection molding, and studied with two different types and loading amounts of UV stabilizers. UV absorbers (UVAs) and hindered amine light stabilizers (HALS) were used as UV stabilizers. A specimen produced without the addition of a UV stabilizer was used as a reference specimen of both the blends. After the accelerated weathering, the addition of a UVA provided an improved, smaller change in color than the addition of HALS. Among the tensile properties, the addition of UV stabilizers clearly improved the tensile strength and tensile modulus for almost all the studied specimens. Additionally, the melt properties of both the studied plastic blends were found to be increased by the addition of UV stabilizers. Post-print / Final draft

Turbine and generator rotors and shafts undergo high stresses during regular working life and, from a safety and operational aspect, are the most significant components of a power generation system. Depending on the appropriate operating conditions, like temperature and/or corrosion the, shafts can be fabricated out of low/high alloy heat resistance material or of low alloyed, highly toughened material for different application. Despite known good practice and developed operation procedures, the failures of shafts sometimes occur. The right and well-defined failure analysis is the basis for feasibility analysis of repair method in the power generating industry. The analysis of direct and indirect costs of repair after the failure analysis as well as the analysis of the repair and post-repair conditions of the repaired element is the vital for decision on the key question. Is it possible to repair this element and what is the optimal repair strategy? This paper compares and analyses two approaches, by weldability analysis and weld cycle simulation, in order to determine welding feasibility analysis of cracked hydro turbine shafts.

This paper describes a curved-layer additive manufacturing technology that has the potential to print plastic components with integral conductive polymer electronic circuits. Researchers at AUT University in New Zealand and the National University of Singapore have developed a novel Fused Deposition Modeling (FDM) process in which the layers of material that make up the part are deposited as curved layers instead of the conventional flat layers. This technology opens up possibilities of building curved plastic parts that have conductive electronic tracks and components printed as an integral part of the plastic component, thereby eliminating printed circuit boards and wiring. It is not possible to do this with existing flat-layer additive manufacturing technologies as the continuity of a circuit could be interrupted between the layers. With curved-layer fused deposition modeling (CLFDM) this problem is removed as continuous filaments in 3 dimensions can be produced, allowing for continuous conductive circuits.

Knowing temperatures at the tool-chip interface is extremely important to optimize the machining condition and to improve the machining performance, furthermore to design high performance materials. In order to grasp the temperature distribution at the tool-chip interface, this study has devised an indexable insert with seven pairs of built-in micro Cu/Ni thermocouples on the rake face near the cutting edge. This paper shows the performance of the indexable insert with built-in micro thermocouples developed. The thickness of each element of the micro thermocouple is approximately 15 μm. The result of unsteady heat conduction analysis employing FEM shows that the temperature difference by installing the micro thermocouples is less than 10 K or 1.2 %. The temperature measurement experiments by cutting of aluminum alloy were carried out by changing the cutting speed. The results provided the evidence that the temperature distribution at the tool-chip interface can be grasped with the indexable insert with built-in micro thermocouples developed.

Buildings are responsible for more than 40% of the energy consumption and greenhouse gas emissions. Thus, increasing building energy efficiency is one the most cost-effective ways to reduce emissions. The use of thermal insulation materials could constitute the most effective way of reducing heat losses in buildings by minimising heat energy needs. These materials have a thermal conductivity factor lower than 0.065 (W/m.K) while other insulation materials such as aerated concrete can go up to 0.11. Current insulation materials are associated with negative impacts in terms of toxicity. Polystyrene, for example contains anti-oxidant additives and ignition retardants. In addition, its production involves the generation of benzene and chlorofluorocarbons. Polyurethane is obtained from isocyanates, which are widely known for their tragic association with the Bhopal disaster. Besides current insulation materials releases toxic fumes when subjected to fire. This paper presents experimental results on one-part geopolymers. It also includes global warming potential assessment and cost analysis. The results show that only the use of aluminium powder allows the production mixtures with a high compressive strength however its high cost means they are commercially useless when facing the competition of commercial cellular concrete. The results also show that one-part geopolymer mixtures based on 26% Ordinary Portland Cement (OPC)+58.3% Fly Ash (FA)+8% Calcined Stuff (CS) +7.7% Calcium Hydroxide (CH) and 3.5% hydrogen peroxide constitute a promising cost efficient (67 euro/m3), thermal insulation solution for floor heating systems with low global warming potential of 443 KgCO2eq/m3.

The construction industry is responsible for high energy and raw materials consumption. Thus, it is important to minimize the high energy consumption by taking advantage of renewable energy sources and reusing industrial waste, decreasing the extraction of natural materials. The mortars with incorporation of phase change materials (PCM) have the ability to regulate the temperature inside buildings, contributing to the thermal comfort and reduction of the use of heating and cooling equipment, using only the energy supplied by the sun. The simultaneous incorporation of PCM and fly ash (FA) can reduce the energetic consumption and the amount of materials landfilled. However, the addition of these materials in mortars modifies its characteristics. The main purpose of this study was the production and characterization in the fresh and hardened state of mortars with incorporation of different contents of PCM and FA. The binders studied were aerial lime, hydraulic lime, gypsum and cement. The proportion of PCM studied was 0%, 20%, 40% and 60% of the mass of the sand. The content of fly ash added to the mortars was 0%, 20%, 40% and 60% of the mass of the binder. It was possible to observe that the incorporation of PCM and fly ash in mortars caused differences in properties such as workability, microstructure, water absorption, compressive strength, flexural strength and adhesion.

This paper describes the numerical investigation on the adsorption () of nanoparticles (NPs) scale inhibitor (SI) using Eulerian Computational Fluid Dynamics (CFD) solver ANSYS/FLUENT® based on a scaled down flow model. The simulation were done to investigate theof normal and nanoscaled Calcium-phosphonate. The phosphonate used was 1-hydroxyethylidene-1, 1-disphosphonic acid (HEDP) SI in order to determine the enhancement in adsorption achieved by the nanoscaled SI. This was done by looking at the change in concentration of the SI particles throughout the simulation time. It was found that the two sizes (normal and nanostructured) of the SI particles result in different change in concentration, hence indicates that the two yields different adsorption to the active sites. For the normal SI, the concentration distribution throughout the column remains almost the same as its initial concentration () of 2000 ppm except for very narrow regions in the vicinity of the wall boundaries. This suggests that the rate of process (of the SI onto the wall) is very slow. Consequently, it will take longer time for the SI to be adsorbed to the column wall, hence indicates that it is less efficient. Meanwhile, the nanoscaled Calcium-HEDP SI rapidly shows a significant change in concentration. At 200 s its concentration has distributed evenly in the range of 1960 ppm to 2000 ppm. This shows a really high rate. The results from this study indicates that the nanoscaled Calcium-HEDP SI has better which shows that it is more efficient than normal-scaled Calcium-HEDP SI.

This paper presents the effect of Jatropha curcas biodiesel on the wear properties of mild steel, which was coated by preplacement of TiC particulate and melting it using a conventional TIG torch arc heat source. The aim of the study is to investigate the wear behaviour of surface modified AISI 4340 steel and the uncoated AISI 4340 steel which were performed using CSM tribometer at four different temperatures viz., 100 °C, 120 °C, 140 °C, and 160 °C, with the presence of jatropha biodiesel. At the end of the tests, wear characteristics was investigated by weight loss measurements and changes of the exposed metal surface. Surface morphology was examined by scanning electron microscope and surface profilometry. EDX analysis was performed on the samples’ surface. Results showed that wear of alloy steel increases with increasing temperature. TiC coated alloy steel showed improved wear resistance as this alloy steel demonstrated lower wear volume loss as compared to the uncoated steel in presence of jatropha biodiesel at higher temperature.

Present paper relates to the field of “smart textiles” and demonstrates the results of research carried out on the development of a new type of knitted sensing elements (knitted resistive fabric (KRP)) which can be integrated in the garment applied for health monitoring. KRP produced from conductive resistive, nonconductive isolating and nonconductive elastomeric yarns. Elastomeric yarn is used as the base yarn and is knitted in the whole fabric, but isolating and resistive yarns (functional yarns) are used as face yarns and knitted in specific sequence. Proposed knitted resistive fabric has high sensitivity to strain deformation and can be used as sensing element to control deformation of the human body parts, joint motion, respiration etc.

Electro-mechanical impedance method is emerging as an important and powerful technique for structural health monitoring (SHM). Active elements of the technique are Piezoelectric Wafer Active Sensor (PWAS) bonded on the structure. Modeling and simulation of PWAS and host structure play an important role in the SHM applications with PWAS. For decades finite element method has been extensively applied in the analysis of piezoelectric materials and structures. In this paper, piezoelectric element and a host metallic structure were modeled using Ansys finite element software to find the Electromechanical Impedance (EMI) according to the signal frequency. After that, the EMI signature of the beam was found for different position of the PWAS patch. The study shows that sensor position may directly control the EMI signature.

As the trend for lighter more efficient structures continues, the requirement for alternative materials follows. One material that has gained attention more recently is porous metallic foam. One drawback to these materials is that there is limited pedigree and understanding of their performance. As with all materials, the use of metallic foam for structures requires knowledge of its mechanical properties; including at high-strain rates. The focus of this paper is to determine the compressive mechanical properties and the influencing parameters for AISI 4340 steel closed-cell foam under high-strain rates (776s-1 to 3007s-1). ANSYS commercial finite element code is used to simulate a closed-cell sample under a split Hopkinson pressure bar test. In this paper the pores are considered to be spherical in shape for simplification while various parameters such as the pore size, the number of pores, the distribution of pores, and the strain rate are varied. Each of these parameters gives this material a unique response which is presented in this paper.

In the ZnO based varistor, the improvement of nonlinear coefficient (α) and prevention of evaporation of Bi2O3 during heat treatments can be achieved by the addition of MnO2 or Co3O4. In this conjunction, it is proper to see the effect of these additives at different low mol percentage and sintering conditions to nonlinear coefficient improvement of the varistor ceramics. In this paper, the investigation regarding to the α variation of Co3O4 doping on ZnO-Bi2O3-TiO2 system is discussed. Here, the crystalline phases were identified by an XRD (PANalytical (Philips) XPert Pro PW3040/60) with CuKα radiation and the data were analyzed by using XPert High Score software. The density of varistor ceramics was measured by the geometrical method. The current-voltage characteristics of the varistor ceramics were evaluated. The average grain size (d) was determined by lineal intercept method. The α of ZnO doped with 0.5 mol% of Bi2O3, 0.5 mol% of TiO2 and x mol% of Co3O4 was calculated from data analysis of current-voltage characteristics obtained through a Source Measure Unit (Keithley 236). The calculation of α is done by using Origin Pro8.0 software. The value of α at low concentration at 1170 °C has the value 5.36 and 3 at 45 and 90 min sintering time, respectively, and then decreases to 4.99 and 2.98 at 0.8 mol% Co3O4 concentrations. When the amount of dopant is increased then the value of α increase up to 0.4 mol% and then the value are slightly dropped after further addition. The addition of Co3O4 dopant in Zn-Bi-Ti oxide ceramics sintered at 45 minutes cause the value of α to increase up to 0.4 mol% and decrease after further addition.

RETRACTED PAPER: The fabrication of nanospinel zinc chromite (ZnCr2O4) crystals by the means of thermal treatment method from an aqueous solution containing metal nitrates, polyvinyl pyrrolidone (PVP), and deionized water was described in this study. The samples were calcined at various temperatures ranging from 773 to 973 K for the decomposition of the organic compounds and crystallization of the nanocrystals. PVP was used as capping agent to control the agglomeration of the particles. The characterization studies of the fabricated samples were carried out by X-ray diffraction spectroscopy (XRD), transmission electron microscopy (TEM), energy dispersed X-ray spectroscopy (EDX) and electron spin resonance spectroscopy (ESR). The corresponding peaks of Zn, Cr and O were observed in the EDX spectrum of the sample which confirms the formation of ZnCr2O4. The XRD patterns also confirmed the formation of the single faced nanocrystallines of spinel ZnCr2O4 with a face-centered cubic structure. The average particle size of the synthesized crystals was also determined from the XRD patterns using the Scherers formula which shows that the crystallite sizes increases with increase in calcination temperature and was in good agreement with the TEM images which shows cubical ZnCr2O4 nanocrystals with uniform morphology and particle size distributions. The ESR spectra confirmed the existence of unpaired electron in the fabricated samples and the increase in g-factor and decreases in resonant magnetic field (Hr) were observed as the calcination temperature increases.

Global warming has been documented as one of the world’s foremost ecological concerns. Although it is difficult to totally end human related global warming, there is a possibility to alleviate these effects through a wide spectrum of options. One such possibility is the reduction of atmospheric carbon dioxide emissions, a major greenhouse gas widely thought to be responsible for global warming. This paper therefore looks at an experimental validation of gas separation by means of a high selective membrane for CO2 recovery applications. Analysis of the results obtained is in good agreement with literature experimental data. Additional results show that CO2 selectivity factor is reasonable for capture of CO2 from N2 as a key constituent in a flue gas stream.

For the purpose of obtaining the characteristic parameters of the asphalt mixture aggregate particles, a viable method using two-dimensional image was put forward in this paper. The automatic detection system of asphalt mixture aggregate characteristic parameters is developed based on VC++. A series of processing are done on the collected aggregate images, including image edge detection, image segmentation, morphological processing, region-labeling, contouring and so on .The region-labeling algorithm is improved ending with low complexity, high robustness. Database technology is used to deal with the storage, query of the results and several other operations. The whole system is characterized with perfect function, user-friendly interface and stable performance, which provides a practical and accurate method for the characteristic detection of asphalt mixture aggregate particles.

The paper is dedicated to the research of calcium-phosphate coatings formed on the surface of the polymer layers (copolymer tetrafluoroethylene with vinylidene fluoride) by pulsed laser deposition. The calcium-phosphate coatings were formed using two different by composition targets. The morphology of the obtained coatings was analyzed by Scanning Electron Microscopy, the elemental composition was analyzed by Energy Dispersive Analysis, and the chemical composition was analyzed by Fourier Transform Infrared Spectroscopy.

The Importance of this Paper is Determined by the Research of Conditions of Photosorption Processes Occurance on the Surface of Aerosol Particles Resulting in the Removal of Toxic Substances from the Atmosphere. Acid-Base Properties of Oxygen-Containing Calcium Compounds being Components of Troposphere Aerosol Particles were Studied by Methods of Ph-Metry and Hammet’s Indicators. the Basic Properties of the Investigated Compounds Surfaces are Predominant Ones: рНiis of Calcium Oxide and Hydroxide has a Value of 9.3 – 9.5, and that for Carbonate and Calcite Equals to 12.3-12.4. Indicator Method Distinguishes Three Areas of Spectrum Corresponding to Lewis Base, and Brensted Neutral and Basic Centers. the Intencity of Peaks is much Higher for Ca(OH)2 and CaO. the Interaction Process of Halogen-Containing Organic Compounds (Freons: 134a, 22 and 12) with Calcium Carbonate Surface under Illumination in Conditions close to Tropospheric Conditions was Studied. it is Shown that the Interaction is the Destructive Photosorption of Freons (134a or 22). the Spectral Dependence of Effective Quantum Yield of Destructive Photosorption is Determined. as a Result of the Interaction Calcium Fluoride and Calcium Chloride are Formed at the Surface.

The design of layers for multilayer flame-resistant glass is a vital task in terms of upgrading fire resistance of window glass units. This paper describes chemical modification of flame-proof acrylate hydrogel layers and shows experimentally how a cross-linking agent — hexamethoxymethylmelamine ether – influences the kinetics of hydrogel polymerization and the enhancement of carbonated structures yield. It has been determined that adding HMMM to the hydrogel composition raises the coke residue yield from 10 % to 35 % and increases the 19 mm thick glass flame resistance class from EI30 to EI50.

Studies have been conducted to investigate biomass accumulation of earthworms (Eisenia fetida andrei), cultivated in the soil media under various concentrations of the slaked lime. The group, which is cultivated on the media with lime concentration 0.1% is characterized by maximum biomass accumulation (average – 120 %). As a result we have discovered two phase kinetic dependence between biomass accumulation of earthworms and the amount of the slaked lime.

In this research the aim was produce a particleboard with alternative materials and evaluated its physical and mechanical characteristics. The raw materials used are residues from sucarcane bagasse (SC) (Saccharum officinarum) and stem leaves of bamboo (B) (Dendrocalamus giganteus), bonded with a bi component adhesive based on castor oil. It was produced particleboards with five different traces: 100% SC, 75% SC+25% B, 50% SC+50% B, 25% SC +75%B and 100 % B. Their physical and mechanical characteristics were evaluated accordingly to Brazilian standard NBR 14810-3. Regarding the results obtained, it can be detached that for physical and mechanical evaluation it is evident a negative relation among the amount the sugarcane bagasse and their physical and mechanical characteristics, that is particleboards with low concentrations of sugarcane bagasse had better results. However all particleboards could be recommended for use as sealing particleboards in the segment of civil construction.

This paper shows a comparison between two different MOSFET structures: a conventional layout (CM) and Diamond (DM - enclosed layout transistor), as tolerance to the Single Event effect - SEE. Both CMOS 0.35μm technology devices types have the same geometric factor (W/L) and during irradiation were monitored continuously to detect and acquire the SEEs applying a new approach with a PXI test system. For this work was used heavy ion beams produced at the São Paulo 8 UD Pelletron accelerator.

Reachstacker is an indispensable handling machinery, it will inevitably lead to unbalanced force at the job site. This paper does transient dynamics analysis for the spreader mechanism, which is one of the most significance key components. We get dynamic response of the spreader in lifting instant, results not only provide a reference for designers to understand the mechanical characteristics of spreader comprehensively, but also bedding for the future research.

The selection of a desirable machine is an important concern for the manufacturing firm. The selection process contains some critical selection attributes and the task of this process is to choose the desirable machine from a number of candidate machines. Then the machine selection problem is actually a multi-attribute decision making problem. This paper will develop a preference selection index method to solve the problem of machine selection in a flexible manufacturing cell. A case study is used to demonstrate that the proposed method is effective and feasible.

the supervising system of flower house's enviroment,which is put into function by the popular series of AT89S52 single machine tablet,mainly measures and controls the major tempreture and humidity of enviroment,which will be revealed by showing system.the paper gives an introduction of system's software,hardware design and the process of performing.the system is easily manured with great utility.at the same time, it worths being popularized and used.

Nowadays, demand for automated Gas metal arc welding (GMAW) is growing and consequently need for intelligent systems is increased to ensure the accuracy of the procedure. To date, welding pool geometry has been the most used factor in quality assessment of intelligent welding systems. But, it has recently been found that Mahalanobis Distance (MD) not only can be used for this purpose but also is more efficient. In the present paper, Artificial Neural Networks (ANN) has been used for prediction of MD parameter. However, advantages and disadvantages of other methods have been discussed. The Levenberg–Marquardt algorithm was found to be the most effective algorithm for GMAW process. It is known that the number of neurons plays an important role in optimal network design. In this work, using trial and error method, it has been found that 30 is the optimal number of neurons. The model has been investigated with different number of layers in Multilayer Perceptron (MLP) architecture and has been shown that for the aim of this work the optimal result is obtained when using MLP with one layer. Robustness of the system has been evaluated by adding noise into the input data and studying the effect of the noise in prediction capability of the network. The experiments for this study were conducted in an automated GMAW setup that was integrated with data acquisition system and prepared in a laboratory for welding of steel plate with 12 mm in thickness. The accuracy of the network was evaluated by Root Mean Squared (RMS) error between the measured and the estimated values. The low error value (about 0.008) reflects the good accuracy of the model. Also the comparison of the predicted results by ANN and the test data set showed very good agreement that reveals the predictive power of the model. Therefore, the ANN model offered in here for GMA welding process can be used effectively for prediction goals.

The cultural ecosystem is a part with the enormous ecological function values in the social ecosystem of the region and town. This paper puts forward the viewpoint that the new resettlement site removed and constructed due to the needs of the ecological environmental protection and poverty relief and development should protect and recover the original cultural ecology of the resettlement area, systematically sets forth the necessity and principle of the cultural ecosystem protection and recovery, and summarizes the contents of the protection and recovery.

Since squeeze casting process is considered as a new technology for light alloys like aluminum and magnesium, more basic research is required for a scientific understanding of the practice. In distinct, as a cost-effective and resource-efficient tool, advanced numerical modelling in conjunction with dynamic boundary conditions and capabilities of predicting the formation of casting defects have to be fully developed for the optimization of squeeze casting processes. In squeeze casting, an external pressure is applied to molten metal before, during and after its solidification, which makes the condition at the casting die interface different from other typical casting techniques. In this paper, Finite Difference Method (FDM) is used to investigate the effect of heat transfer during squeeze casting process and the relationship between casting temperature and solidification on Al-Si alloys.

Debinding is one of the most critical and time consuming stage in metal injection moulding (MIM). German and Bose (1997) reported that early debinding practice relied on thermal binder degradation, requiring up to 300 hours for complete binder removal. Today multi-stage debinding techniques are introduced cutting down the debinding time to as little as 2 hours. This work investigates solvent debinding variables prior to thermal debinding. Solvent debinding is carried out in n-heptane. Wax and stearic acid are the target binder components being leached out from the green bodies, with wax as the major constituent in the binder formulation. Debinding is conducted at 50, 55, 60 and 65°C for 1-4 hours at each temperature. Weight loss measurements were done. For porosity and surface appearance, scanning electron microscope (SEM) analysis and visual inspection were done. Samples de-bound at 65°C showed an appreciable amount of mass loss; however, surface cracks and warping were observed. A 60°C temperature and time of 4 hours demonstrated best results i.e. a satisfactory mass loss, absence of surface cracks and no warping. Mass loss is directly proportional to temperature and time. SEM results are discussed in the paper.

An important step of a new process being developed for the beneficiation of the mineral zircon (Zr (Hf)SiO4) to produce nuclear grade zirconium (Zr) metal, is the separation of the Zr from the hafnium (Hf). Zr ores typically contain between 1 and 3% Hf , whereas the use of Zr metal in the nuclear industry requires a Hf content 2•SiO2) with ammonium bifluoride (ABF). The separation involves the selective sublimation of the two tetrafluorides in an inert atmosphere under controlled conditions, and subsequent similarly selective desublimation. An accurate estimation of the sublimation rates the zirconium tetrafluoride (ZrF4) and hafnium tetrafluoride (HfF4) as a function of temperature is required since this forms the basis of the development of a sublimation model to determine whether the concept under consideration is theoretically possible. The sublimation kinetics of ZrF4is reported in this paper.

金沢大学融合研究域融合科学系, The purpose of this paper is to present a new predictive control utilizing online data and stored data of input/output of the controlled system. The conventional predictive control methods utilize the mathematical model of the control system to predict an optimal future input to control the system. The model is usually obtained by a standard system identification method from the measured input/output data. The proposed method does not require the mathematical model to predict the optimal future control input to achieve the desired output. This control strategy, called just-in-time, was originally proposed by Inoue and Yamamoto in 2004. In this paper, we proposed a simplified version of the original just-in-time predictive control method. © (2014) Trans Tech Publications, Switzerland., 研究者情報DB