IJOER : April 2016

Dynamic analyses of a flat plate and a beam subjected to a moving load

Electron-acoustic solitons and double layers in a plasma system with Tsallis distributed hot electrons

Abstract A theoretical investigation is carried out for understanding the properties of electron acoustic solitary waves and double layers in an unmagnetized plasma whose constituents are cold electron fluid, hot electrons obeying Tsallis distribution and stationary ions. The Sagdeev potential approach is employed to carry out the analysis. The amplitude and nature of electron-acoustic solitary waves (EASWs) and electron-acoustic double layers (EADLs) are found to be extremely sensitive to the degree of nonextensivity. It is found that the present plasma model supports only rarefactive solitons and double layers depending on the q nonextensive parameter. The investigation shows that solitary structure ceases to exist when the parameter q crosses a certain limit.

Keywords Electron acoustic wave, Solitons, Double layer, Tsallis distribution.

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The Effect of Type Two Diabetes Mellitus on Superoxide Dismutase (SOD) Activity and its Correlation with HbA1c in Iraqi Patients

Abstract Diabetes mellitus (DM) is a group of metabolic disorders, characterized by hyperglycemia resulting from defects in insulin action, insulin secretion or both. Increasing evidence suggests that the oxidative stress plays a role in the pathogenesis of diabetes mellitus and its complications. The current study includes (130) T2DM patients (group P) [51 males and 79 females with an ages range (35 to 55) and ages mean 49.89 years], they are sub-grouped into three categories according to their HbA1c value. Patients with HbA1c less than 7 are considered as good controlled diabetic patients (30 patients) (group P1), while patients with HbA1c between 7 and 8 were considered as medium controlled diabetic patients (40 patients) (group P2), and the patients whom their HbA1c more than 8 are considered as poorly controlled diabetic patients (60 patients) (group P3). The results of patients group were compared with control healthy subjects (35 subjects) (group C) [14 males and 21 Females were with an age range from 35 to 55 years and ages mean 45.51 years]. Patients and controls were characterized in terms of glycated hemoglobin (HbA1c), serum levels of Cu (μg/L), Zn (μg/L), malondialdehyde (MDA) (mmol/L) and superoxide dismutase activity (SOD) activity (U/ml). The HbA1c has been found to be significantly higher in diabetic patients group (P) in comparison to group C. Serum Zn level has been found to be significantly lesser in group P in comparison to group C. Serum Cu level showed an increase in group P, although it is not significance in comparison to group C. Serum SOD activity shown a significant decrease in group P in comparison to group C. Serum MDA level showed a significantly higher value in diabetic patients group P in comparison to group C. The serum Zn was decreased as HbA1c increased i.e. serum Zn level in group C was higher than patients groups, and its value in group P1 higher than group P2 and that was higher than group P3, while serum Cu level was increased as HbA1c increase, i.e. serum Cu level in group P3 higher than group P2 and that higher than group P1, while group C gave the maximum value. The serum SOD activity was decreased as HbA1c increased, i.e. SOD activity was found to be significantly higher in group P1 in comparison with group P2 and P3, while serum MDA level in group P3 was significantly higher than group P2, and P1.

Keywords EC-SOD, hyperglycemia, MDA, SOD, T2DM.

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Hydrodynamic torque converter operating under dynamic load

Abstract Unsteady interaction phenomena created by the influence of the blade spacing have been reported in earlier experiments and CFD. However cyclic load changes in start-up and slow-down of the hydrodynamic torque converter operation have been beyond access to the current flow field calculation methods due to the extensive computer run time and memory requirements in the application of time dependent Navier-Stokes solvers to acceleration and deceleration. Therefore computations based on the use of 1D mean-line flow simulation supported by optimised flow correction coefficients tuned in rig-test experiments enable to obtain solutions for engineering-type technical problems.

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Characterizations of Type-2 Harmonic Curvatures and General Helices in Euclidean space E⁴

Abstract In this study, we introduce quaternionic type-2 Harmonic Curvatures and General Helices according to Frenet frame in 4-dimensional Euclidean Space and investigate its properties for two cases. In the first case; we use a constant angle between a unit and fixed direction vector field and the first relatively Frenet frame vector field of the curve, that is given in the paper.

where is the real quaternion inner product. Since the relatively Frenet frame vector field of the curve makes a constant angle with the unit and fixed direction vector field U, we call this curve as a General helix in 4-dimensional Euclidean Space . And then, in the other case, we define new type-2 harmonic curvature functions and we give a vector field which we call Darboux vector field for General helix. And then we obtain some characterizations for General helix in terms of type-2 harmonic curvature functions and the Darboux vector field .

Keywords Euclidean spaces, General helix, type-2 harmonic curvatures, Quaternion algebra, Quaternionic frame.

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Hydrothermal growth of nanostructured Zinc oxide

Abstract Hydrothermal method was used to prepare ZnO nanostructure. This study haven’t used any catalyst or buffer layer before the reaction. The process has taken place inside Teflon lined stainless steel autoclave with volume 100 ml (homemade). ZnO nanotubes, lettuce leaf nanostructure, and nanosticks were successfully synthesized using ZnO nanoparticles (20-30 nanometers) and NaOH (concentrations 6M) which was the starting materials for the chemical reaction under stirring. The suspension was transferred into a Teflon lined sealed stainless steel autoclave and kept at 70 0C for 24, 48, and 72 hour. The influence of the time reaction of synthesis process on the morphology, the crystallinity and structural properties are studied by X-ray diffraction and field emission scanning electron microscope (FE-SEM), the experimental pattern of the films show that diffraction peaks can be assigned to the Wurtzite hexagonal-shaped ZnO as shown in the FE-SEM pictures, also the morphology of the films studied by atomic force microscope (AFM) shows that the prepared thick films have high roughness specially for the powder prepared 48 h .

Keywords ZnO, nanotubes, lettuce leaf structure, nanosticks, dislocation density.

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Information Disseminated with Technology Firms on Social Media

Abstract Technology startups going public to build a sustainable company that is public, as we see hot technology initial public offerings (IPOs) – Twitter, Alibaba, and the like-went to public in past years. We examine the IT-Producing IPOs versus IT-Consuming IPOs on their first-day returns and long-run underperformance. We investigate the social media content on IT-Producing IPOs versus that on IT-Consuming IPOs and find that IT-Producing IPOs are actively using Twitter to inform consumers while IT-Consuming IPOs are tweeting to getting feedbacks and inputs from consumers. In addition, IT-Producing IPOs dominate over IT-Consuming IPOs in terms of the attention attracted from social media users as measured by the volume of the social media content posted on them

Keywords social media content, initial public offering, technologies.

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Discovery of fraud in Medical Insurance

Abstract The term insurance fraud refers to the commission of any act with the intent to obtain an outcome that is favorable, but fraudulent during an insurance claim. Including single prescription medicines is extremely high, card repeatedly within a certain amount of time for medicine, etc. This paper is based on methods of hierarchical cluster analysis and generalized squared distance discriminate method to record medical coverage of transaction data at outliers for finding out the corresponding abnormal record which indicates potential fraud.

Keywords medical insurance fraud, hierarchical cluster analysis, training sample, generalized square distance discrimination.

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An empirical analysis about forecasting Tmall air-conditioning sales using time series model

Abstract Time series model is a hotspot in the research of statistics. On November 11, 2015, Tmall platform’s turnover was more than $91.2 billion which caused the attention of scholars both at home and abroad. So this paper aims to forecast sales of Tmall, which is helpful to the enterprises. Research methods are ARIMA model and VAR model. The first model is single-variable model and the later is multi-variable model. In the study, ARIMA model makes the sequence smooth by using two difference operation. In VAR model, five explanatory variables are transformed into one main component. By contrast, VAR model does not give detailed accurate prediction, but ARIMA model does. Therefore, single-variable time series model is more suitable for sales forecast than multi-variable model.

Keywords ARIMA model, VAR model, Sales forecast.

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Diffusion of Toluene and Ethylene in ZSM-12 zeolite: Experimental and numerical study

Abstract The Na+ and Ag+ forms of ZSM-12 zeolite microporous were used as effective adsorbents for hydrocarbons trap. Diffusion of a single adsorbed component including ethylene as a light molecule or toluene a heavier one inside a narrow one-dimensional channel was studied. Experimental desorption profiles for these two gases desorbing from both Ag-ZSM-12 and Na-ZSM-12 were obtained at very high heating rates comparable with the one observed during the cold start of a combustion engine. Numerical simulation based on Fick’s law and a transient diffusion boundary value yielded a good fitting of these experimental results. For both ZSM-12 forms considered in this study, diffusion activation energies Eω and EΞ for toluene are much higher than those for ethylene. The values of these parameters are higher for the Ag+ exchanged zeolite than for Na-ZSM-12 and related to the presence of strong Lewis acid sites in the former material. In addition each activation energy for Na-ZSM-12 and Ag-ZSM-12 decreases at increasing heating rate. This was explained by thermal vibrations of the zeolite lattice which allow higher diffusivity at high temperature.

Keywords single component, single file diffusion, temperature-programmed desorption, ZSM-12

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Missing Data Imputation Methods in Classification Contexts

Abstract We examine different imputation methods that deal with missing data in classification contexts and compare the performance of the methods with an experiment study. We investigate the performance of the methods under the assumption that data are missing at random. We find that, as the number of missing holes in data increases, the imputation methods deteriorate and the misclassification rates of the imputation methods increase. We also examine the scenario where missing data are due to strategic behaviors of data providers. We find that imputation methods play an important role at deterring strategic behaviors of data providers and minimizing the misclassification rate.

Keywords missing data, imputation method, classification.

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Monitoring of Bubble Formation during the Boiling Process Using Acoustic Emission Signals

Abstract The bubble cavitation phenomenon in two phase gas/liquid systems happens in several hydraulic components, for example, valves and centrifugal pumps. This is a common occurrence, leading to a drop in hydraulic performance, reduction of equipment efficiency, possible damage to the structure of pump and valve components. In addition, it causes high vibration and noise and solid surface erosion. This study identifies the feasibility of the use of the Acoustic Emission technology to detect and monitor bubble formation throughout boiling processes. To undertake this task a special purpose test-rig was employed. It was concluded that bubble formation is detectable with AE technology and there is a clear correlation between increasing AE levels and the bubble formation during the boiling process.

Keywords Acoustic Emission (AE), Vibration and Noise, Solid Surface Erosion Bubble Formation, Boiling.

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Development of collagen-EDC scaffolds for skin tissue engineering: physicochemical and biological characterization

AbstractA leading consequence of burns is the loss of large extensions of skin. Thus, skin tissue engineering has been increased and promoted development of biomimetic skin scaffolds. Type I collagen is one of the most materials used in tissue engineering due to its biological characteristics. However, the applications of collagen as biomaterial are severely limited by its reduced physicochemical and mechanical properties, such as high susceptibility to enzymatic degradation in vivo and low thermo stability. To enhance collagen properties, crosslinked collagen scaffolds at different concentrations of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) were prepared by freeze-drying technique. The effect of crosslinking and concentration on scaffolds physicochemical and biological behavior was evaluated. Scaffolds morphology was observed by Scanning Electron Microscopy, showing in all cases an appropriate microstructure for biological applications. Differential Scanning Calorimetric showed an increase in shrinkage temperature (TS) with increase in EDC concentration. Infrared Spectroscopy suggested that the secondary structure of collagen is not affected after the crosslinking. Enzymatic degradation test indicated that scaffolds treated with EDC dissolved slowly in enzymatic solution (just 12% of degradation after 96 h). Cell viability and attachment tests suggested that EDC treatment do not affect the excellent biological characteristics of collagen.

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Automatic Train Control Algorithms with Regulation Restrictions Adaptive to System State Changes

Abstract Centralized automatic train control algorithm is proposed which allows effective adjustment of each train’s departure and running times or intervals when there are unscheduled delays. The novelty lies in that it employs three sets of methods, called regulative characteristics, which contain relationships between regulation restrictions (minimal station dwell times and train running times). These relationships are obtained a priori from the simulation of train circulation on the detailed railway or metro line model, saving later onboard real-time processing requirements, which is especially useful for those train control systems which are being only partially modernized. In the traditional algorithms these regulation restrictions are frequently considered fixed, while the changes of system’s state do affect them, so the usage of the values recurrently updated by the regulative characteristics allows to have more flexible running and station times for every train on the line. The efficiency of the new algorithm is additionally increased by the usage of forecasting of station dwell times and train running times based on the history of these values for each train or station. Proposed algorithm decreases the quantity of undesired stops between stations, allowing to save energetic resources spent on repeated train acceleration and to raise, in general, the quality of the transportation process algorithm has been tested on Mexico Metro Line simulator confirming efficiency increase of 3% for the worst case scenario and up to 10% for the best cases (busiest state of the line plus additional temporal speed limits).

Keywords— Railway transportation, Automatic Train Control, Metro, Regulation Algorithms, Centralized Control, Forecasting.

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On magnetite concentrate grains with respect to their use in concrete

Abstract Magnetic iron oxide grains and/or micrograins embedded into concrete are suggested for pH-protection of concrete. To this aim a phenomenological formula for the change in pH of the water solution after contacting iron oxides was derived. It has a broader meaning because it refers to all materials for which surface electric potential varies with pH of the contacting solution. It may be used to design a suitable composition of the mortar. In addition, the important property of magnetite concentrate grains that they may increase compressive strength of the mortar is shown. In the study, all the mortar under consideration was made from Portland cement CEM I 42.5 R, natural aggregate – quartz sand fraction 0‑2 mm and magnetic material was magnetite concentrate supplied by Magnetite‑Grochow Sp. z o. o.

Keywords compressive strength, concrete, magnetite concentrate, magnetite grains, pH value.

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Adaptive Backstepping Tuning Functions Control Design for Industrial Robot Manipulators

Abstract In this paper, an adaptive backstepping control design with tuning functions and K-filters for robot manipulators is developed. A stronger stability and convergence performance of the designed control in comparison with backstepping observer is achieved despite the presence of disturbances, parameter uncertainties, system nonlinearities for a real-time system of a single-link flexible-joint manipulator.

Keywords Tuning functions, K-filters, Adaptive Observer Backstepping, Robot Manipulator Control.

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Implementation of AES algorithm

Abstract Data security has become one of the most important concerns in the recent times. This has led to an increase in the importance of cryptography of the electronic data. Cryptography is the process of protecting digital information. Though there are numerous encryption systems used in security systems by various organizations, for the wider use, a particular encryption method is used as a standard. The internationally accepted and acclaimed algorithm is Advanced Encryption Standard (AES). Here in this design we are implementing the Advanced Encryption Standard (AES) with a key length of 128 bits using Verilog hardware description language (HDL).

Keywords Advanced Encryption Standard (AES), cryptography , Cipher, Encryption, Field Programmable Gate Array (FPGA), Hardware description language(HDL), National Institute of Standards and Technology (NIST) , Verilog.

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Effects of curing systems and light units on cytotoxicity of dental composites

Abstract— The objective of this study was to examine and compare the cytotoxicity behavior of commercial two restorative (light-cured) and three adhesive composites (dual-cured) polymerized by using two different light curing units (LCU). Commercial composites Filtek Z250, Filtek Supreme XT, Rely X Arc, Rely X U100 and Variolink II were polymerized using different light densities of halogen (H) and Light Emitting Diod (LED) curing units. After the polymerization process samples sterilized under UV light for 15 minutes. Dulbecco’s Modified Eagle’s Minimal Essential Medium (DMEM) containing 200 µL of serum was placed in 96 well cell plates and samples were added in the wells. They were incubated 5% CO2 incubator for 48 hours at 37°C. Sample surface area/solution volume was adjusted to 2.5 cm2/ml. Cytotoxicity of samples was examined by the extraction method and the results were evaluated using the MTS test. The extracts of the samples were collected for 24 hours and incubated in L-929 mouse fibroblast cells (MFCs). The data was analyzed with the SPSS statistics program. Samples polymerized by H light source were generally cytotoxic than the samples polymerized by LED light source. Rely X Arc in dual-cure system is the most biocompatible material and Variolink II-LED combination is the most cytotoxic one. Furthermore, there was no statistically significant difference between the cytotoxicity levels of composites using H and LED light sources (p>0.05).This study showed that the curing treatment used power density LED affects biocompatibility positively and nano-structures increase the biocompatibility.

Keywords— Cytotoxicity, dental composites, light curing, dual curing, halogen, LED, light curing units.

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Methodologies and Results of a Two -Year Project Promoting Integrated Pest Management and Chemical Use Reduction to Promote Science and Improve Health

Abstract Researchers from three universities worked with multiple 6-12 grade teachers from 2013 to 2015to engage them and their students in developing science projects and learning applied science concepts. These projects focused on integrated pest management (IPM) and chemical use reduction (CUR) in the home. The objectives of the program consisted of increasing awareness about IPM and CUR, and promoted inquiry based leaning, while employing a new model of engagement in the classroom (i.e., liberating structures). Arm 1 of the program first engaged a large group of teachers (i.e., 75) in two-day trainings. A selected group of trained teachers then joined with researchers and trained graduate students to actively engage their 6-12 grade students in the classroom. Arm 2 involved the development and implementation of a more focused 10-day IPM and CUR curriculum to be used in the classroom, along with a 4-hr online training for teachers designed to facilitate its implementation. In an effort to create a balanced and comprehensive experience for those who participated, researchers from graduate science and communication, and K-12 STEM programs composed the project team. This article reports on the methodologies employed, experiences and overall metrics of the program. Recommendations are given to improve the process and the results based on participant experiences. Useful information is provided for those in the field planning to better engage the community and in particular 6-12 grade students in science and health education. Curriculum and other materials (i.e., brochures) are available at no cost online in English and Spanish.

Keywords Liberating Structures (LS), Science Education, K-12 Science, Integrated Pest management (IPM), Chemical Use Reduction (CUR), Community Outreach.

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Influence of Operating Conditions of the Steel Cord on the Structure and Selected Mechanical and Technological Properties of High Carbon Steel

Abstract When buying tires, we would like them to serve us as long as possible. Experts of the independent organisation Dekra, based on case studies found that after six years the risk of tire failure increases drastically, which is why they recommend replacement of tires after six years of operation at the latest. The results of the presented studies have shown that operation of the car tires in such extreme conditions as continuous contact with ground, frequent braking and repeated hitting against bumps in the road leads to delamination of the steel material of belting and decrease in its mechanical properties by about 35-48% compared to the reference material.

Keywords Eutectoid Steel, Cord, Belt, Non-Metallic Inclusions

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Cascaded Model-Free Fuzzy Control: an Application to the Coupled Tanks System

Abstract This report proposes a design methodology for cascaded model-free fuzzy control systems. The ordinary Mamdani approach is modified in order to use expert knowledge for variable set-point control without any need of the system model. The methodology is successfully tested in a sub-actuated, naturally delayed setup, known as the coupled tanks system, where the water level is maintained at different set points, both in simulation and in real time.

Keywords Cascade Systems, Coupled Tanks, Fuzzy Control, Variable Set Point Control.

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On The Reproductive Number of HIV/AIDS Patients in Nigeria

Abstract This paper presents the basic reproductive number of HIV/AIDS in Nigeria as well as endemic prevalence using the SIR model developed by Mckendric (2001).

The Basic reproduction number Ro determines if the disease is transmissible or it will die a natural death, and the endemic prevalence gives a clue on the rate of transmission of the disease. This study obtained both the Ro and the endemic prevalence as a tool for controlling the endemic in an SIR model of disease dynamics.

Keywords Endemic prevalence, Basic Reproductive number, Disease transmission, Disease dynamics

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Sensitivity Analysis for Prediction of Bead Geometry using Plasma Arc Welding in Bellows Segment

Abstract The automated welding systems, have received much attention in recent years, because they are highly suitable not only to increase the quality and productivity, but also to decrease manufacturing time and cost for a given product. To get the desired quality welds in automated welding system is challenging, an algorithm is needed that has complete control over the relevant process parameters in order to obtain the required bead geometry. However, there is still the lack of algorithms that can predict bead geometry over a wide range of welding conditions. Therefore, to solve this problem, this paper investigated the relationship between the process parameters and the bead geometry in Plasma arc welding (PAW). The quantitative effect of process parameters on bead geometry was calculated using sensitivity analysis. From the experimental results, the developed algorithm can predict the bead dimensions within 0–10% accuracy from analyzed parameters. It also showed that the change of process parameters affects the bead width relatively stronger than bead height.

Keywords Plasma Arc Welding, Bellows Segment, Sensitivity Analysis, Factorial Design, Optimization, Bead Geometry.

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Preservation of cardiopulmonary blocks: A real and interactive biomaterial for teaching and learning lung plethysmography and mechanical ventilation

Abstract The introduction of biomaterials to thoracic training has an important impact on human health and has significant economic benefits. We present a real, reusable and low-cost biomaterial that is a useful tool in teaching and learning training programs for lung plethysmography and mechanical ventilation procedures. At the end of non-cardiopulmonary-related research studies, five cardiopulmonary blocks were harvested from rabbits (3), a dog (1) and a cat (1). Cardiopulmonary blocks were preserved with McCormick’s solution and impregnated with glycerin-phenic acid. Subsequently, the cardiopulmonary blocks were connected to a volume ventilator to ensure good lung compliance and that there was no leakage. An acrylic plethysmograph was designed, and cardiopulmonary blocks were placed through an endotracheal tube and connected to a ventilator. Lungs were insufflated under four different inspiratory pressures (10, 12, 14 and 16 cmH2O), and respiratory parameters were calculated. Although it was necessary to significantly increase the inspired tidal volume and the compliance decreased (ANOVA + Student’s t: p<0.05) compared to the values required for blowing non-preserved cardiopulmonary blocks, all the preserved cardiopulmonary blocks maintained their structural integrity, and the lungs were shown to be elastic pieces with smooth texture, along with distension and insufflation capacities. This biomaterial was shown to be functional and reusable for the teaching and learning of lung plethysmography and mechanical ventilation practices.

Keywords Cardiopulmonary Block, Preservation, Biomaterial, Plethysmography, Education.

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Hydrodynamic torque converter operating under dynamic load

Abstract Unsteady interaction phenomena created by the influence of the blade spacing have been reported in earlier experiments and CFD. However cyclic load changes in start-up and slow-down of the hydrodynamic torque converter operation have been beyond access to the current flow field calculation methods due to the extensive computer run time and memory requirements in the application of time dependent Navier-Stokes solvers to acceleration and deceleration. Therefore computations based on the use of 1D mean-line flow simulation supported by optimised flow correction coefficients tuned in rig-test experiments enable to obtain solutions for engineering-type technical problems.

Keywords— hydraulic torque converter, automobile.

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The Influence of a Static Magnetic Field on the Behavior of a Quantum Mechanical Model of Matter

AbstractThe paper presents an experimental measurement of a material inserted in various types of magnetic field. The related model accepts the time component of an electromagnetic field from the perspective of the properties of matter. Relatively moving systems were derived and tested [1], and the influence of the motion on a superposed electromagnetic field was proved to exist already at relative motion speeds. In micro- and nanoscopic objects, such as the basic elements of matter, the effect of an external magnetic field on the growth and behavior of the matter system needs to be evaluated. We tested the model based on electromagnetic field description via Maxwell’s equations, and we also extended the monitored quantities to include various flux densities. Experiments were conducted with growth properties of simple biological samples in pre-set external magnetic fields.

Keywordsexternal magnetic field, numerical model, magnetic flux density, homogenous magnetic field.

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Duplex Stainless Steel Self-ligating Orthodontic Brackets by Micro-powder Injection Moulding

Abstract This work deals with the production of duplex stainless steel dental brackets by micro-powder injection moulding employing a thermoplastic binder based on high density polyethylene and paraffin wax. The starting powder was a mixture of ferritic and austenitic gas-atomized powders in a volume ratio of 50/50. Feedstocks with powder loadings of 50, 60, 65 and 68 vol.% were prepared. All feedstock compositions presented a pseudoplastic flow behaviour. The critical powder volume concentration experimentally determined through oil absorption method and applying a rheological model was 71 vol.%. A mixture with a 65 vol.% of solid loading was chosen to perform the complete route. Injection moulding stage was successfully carried out and green parts were obtained with an accurate dimensional precision. Green brackets were thermally debound under a cycle developed on the basis of thermogravimetric analysis. The cycle took place under argon atmosphere to prevent the oxidation of metallic powder and it lasted only 4 hours. Samples were successfully sintered in low vacuum at 1250ºC, final parts reached densities close to 98%. Scanning electron micrographs revealed a biphasic microstructure distinctive of duplex stainless steels.

Keywords duplex stainless steel, thermoplastic binder, micro-powder injection moulding.

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