Search results for: earth size

Authors: O. Arbouche, Y. Benallou, K. Amara

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We report a first-principles study of structural, electronic and magnetic properties of ternary plumbides (rare earth-transition metal-Plumb) Dy2Ni2Pb crystallizes with the orthorhombic structure of the Mn2AlB2 type (space group Cmmm), were studied by means of the full-relativistic version of the full-potential augmented plane wave plus local orbital method within the frame work of spin-polarized density functional theory (SP-DFT). The electronic exchange-correlation energy is described by generalized gradient approximation (GGA). We have calculated the lattice parameters, bulk modulii and the first pressure derivatives of the bulk modulii, total densities of states and magnetic properties. The calculated total magnetic moment is found to be equal to 9.52 μB.

Keywords: spin-polarized, magnetic properties, Dy2Ni2Pb, Density functional theory

Procedia PDF Downloads 295

Authors: Zhuomin Zou, Thijs Van Landeghem, Elke Gruyaert

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Using supplementary cementitious materials, such as blast-furnace slag and limestone, to replace cement clinker is a promising method to reduce the carbon emissions from cement production. To efficiently use slag and limestone, it is necessary to carefully select the particle size distribution (PSD) of the binders. This study investigated the effects of the PSD of binders on the performance of slag-limestone ternary cement. The Portland cement (PC) was prepared by grinding 95% clinker + 5% gypsum. Based on the PSD parameters of the binders, three types of ternary cements with a similar overall PSD were designed, i.e., NO.1 fine slag, medium PC, and coarse limestone; NO.2 fine limestone, medium PC, and coarse slag; NO.3. fine PC, medium slag, and coarse limestone. The binder contents in the ternary cements were (a) 50 % PC, 40 % slag, and 10 % limestone (called high cement group) or (b) 35 % PC, 55 % slag, and 10 % limestone (called low cement group). The pure PC and binary cement with 50% slag and 50% PC prepared with the same binders as the ternary cement were considered as reference cements. All these cements were used to investigate the mortar performance in terms of workability, strength at 2, 7, 28, and 90 days, carbonation resistance, and non-steady state chloride migration resistance at 28 and 56 days. Results show that blending medium PC with fine slag could exhibit comparable performance to blending fine PC with medium/coarse slag in binary cement. For the three ternary cements in the high cement group, ternary cement with fine limestone (NO.2) shows the lowest strength, carbonation, and chloride migration performance. Ternary cements with fine slag (NO.1) and with fine PC (NO.3) show the highest flexural strength at early and late ages, respectively. In addition, compared with ternary cement with fine PC (NO.3), ternary cement with fine slag (NO.1) has a similar carbonation resistance and a better chloride migration resistance. For the low cement group, three ternary cements have a similar flexural and compressive strength before 7 days. After 28 days, ternary cement with fine limestone (NO.2) shows the highest flexural strength while fine PC (NO.3) has the highest compressive strength. In addition, ternary cement with fine slag (NO.1) shows a better chloride migration resistance but a lower carbonation resistance compared with the other two ternary cements. Moreover, the durability performance of ternary cement with fine PC (NO.3) is better than that of fine limestone (NO.2).

Keywords: limestone, particle size distribution, slag, ternary cement

Procedia PDF Downloads 122

Authors: Geraldine Giraldo

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In the research of advanced materials, ceramics based on KNN are an important topic, especially for multifunctional applications. In this work, the physical, structural, and microstructural properties of the (KNN-CaLi-xSm) system were analyzed by varying the concentration of samarium, which was prepared using the conventional solid-state reaction method by mixing oxides. It was found that the increase in Sm+3 concentration led to higher porosity in the sample and, consequently, a decrease in density, which is attributed to the structural vacancies at the A-sites of the perovskite-type structure of the ceramic system. In the structural analysis, a coexistence of Tetragonal (T) and Orthorhombic (O) phases were observed at different rare-earth ion contents, with a higher content of the T phase at xSm=0.010. Furthermore, the structural changes in the calcined powders at different temperatures were studied using the results of DTA-TG, which allowed for the analysis of the system's composition. It was found that the lowest total decomposition temperature occurred when xSm=0.010 at 770°C.

Keywords: perovskite, piezoelectric, multifunctional, Structure, ceramic

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Authors: Sudhir Kumar, V. R. Sinha

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Background: The topical and systemic toxicity associated with present nonmelanoma skin cancer (NMSC) treatment therapy using 5-Fluorouracil (5-FU) make it necessary to develop a novel delivery system having lesser toxicity and better control over drug release. Solid lipid nanoparticles offer many advantages like: controlled and localized release of entrapped actives, nontoxicity, and better tolerance. Aim:-To investigate safety and efficacy of 5-FU loaded solid lipid nanoparticles as a topical delivery system for the treatment of nonmelanoma skin cancer. Method: Topical solid lipid nanoparticles of 5-FU were prepared using Compritol 888 ATO (Glyceryl behenate) as lipid component and pluronic F68 (Poloxamer 188), Tween 80 (Polysorbate 80), Tyloxapol (4-(1,1,3,3-Tetramethylbutyl) phenol polymer with formaldehyde and oxirane) as surfactants. The SLNs were prepared with emulsification method. Different formulation parameters viz. type and ratio of surfactant, ratio of lipid and ratio of surfactant:lipid were investigated on particle size and drug entrapment efficiency. Results: Characterization of SLNs like–Transmission Electron Microscopy (TEM), Differential Scannig calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), Particle size determination, Polydispersity index, Entrapment efficiency, Drug loading, ex vivo skin permeation and skin retention studies, skin irritation and histopathology studies were performed. TEM results showed that shape of SLNs was spherical with size range 200-500nm. Higher encapsulation efficiency was obtained for batches having higher concentration of surfactant and lipid. It was found maximum 64.3% for SLN-6 batch with size of 400.1±9.22 nm and PDI 0.221±0.031. Optimized SLN batches and marketed 5-FU cream were compared for flux across rat skin and skin drug retention. The lesser flux and higher skin retention was obtained for SLN formulation in comparison to topical 5-FU cream, which ensures less systemic toxicity and better control of drug release across skin. Chronic skin irritation studies lacks serious erythema or inflammation and histopathology studies showed no significant change in physiology of epidermal layers of rat skin. So, these studies suggest that the optimized SLN formulation is efficient then marketed cream and safer for long term NMSC treatment regimens. Conclusion: Topical and systemic toxicity associated with long-term use of 5-FU, in the treatment of NMSC, can be minimized with its controlled release with significant drug retention with minimal flux across skin. The study may provide a better alternate for effective NMSC treatment.

Keywords: 5-FU, topical formulation, solid lipid nanoparticles, non melanoma skin cancer

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Authors: A. P. Srivastava, D. Srivastava, D. J. Browne

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Relaxation dynamics of Zr44Cu40Al8Ag8 bulk metallic glass (BMG) has been probed using dynamic mechanical analyzer. The BMG sample was casted in the form of a plate of dimension 55 mm x 40 mm x 3 mm using tilt casting technique. X-ray diffraction and transmission electron microscope have been used for the microstructural characterization of as-cast BMG. For the mechanical spectroscopy study, samples in the form of a bar of size 55 mm X 2 mm X 3 mm were machined from the BMG plate. The mechanical spectroscopy was performed on dynamic mechanical analyzer (DMA) by 50 mm 3-point bending method in a nitrogen atmosphere. It was observed that two glass transition process were competing in supercooled liquid region around temperature 390°C and 430°C. The supercooled liquid state was completely characterized using DMA and differential scanning calorimeter (DSC). In addition to the main α-relaxation process, presence of β relaxation process around temperature 360°C; below the glass transition temperature was also observed. The β relaxation process could be described by Arrhenius law with the activation energy of 160 kJ/mole. The volume of the flow unit associated with this relaxation process has been estimated. The results from DMA study has been used to characterize the shear transformation zone in terms of activation volume and size. High fragility parameter value of 34 and higher activation volume indicates that this alloy could show good plasticity in supercooled liquid region. The possible mechanism for the relaxation processes has been discussed.

Keywords: DMA, glass transition, metallic glass, thermoplastic forming

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Authors: Katawut Kaewbanjong

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We analyzed a volume of data and found significant user satisfaction in software project factors. A statistical significance analysis (logistic regression) and collinearity analysis determined the significance factors from a group of 71 pre-defined factors from 191 software projects in ISBSG Release 12. The eight prediction models used for testing the prediction potential of these factors were Neural network, k-NN, Naïve Bayes, Random forest, Decision tree, Gradient boosted tree, linear regression and logistic regression prediction model. Fifteen pre-defined factors were truly significant in predicting user satisfaction, and they provided 82.71% prediction accuracy when used with a neural network prediction model. These factors were client-server, personnel changes, total defects delivered, project inactive time, industry sector, application type, development type, how methodology was acquired, development techniques, decision making process, intended market, size estimate approach, size estimate method, cost recording method, and effort estimate method. These findings may benefit software development managers considerably.

Keywords: prediction model, statistical analysis, software project, user satisfaction factor

Procedia PDF Downloads 117

Authors: Norshazmira Mat Azmi, Sayidal El Fatimah Masnan, Shatirah Akib

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More than 70% of the Earth is covered by oceans, which are considered to possess boundless renewable energy, such as tidal energy, tidal current energy, wave energy, thermal energy, and chemical energy. The hybrid system help in improving the economic and environmental sustainability of renewable energy systems to fulfill the energy demand. The concept of hybridizing renewable energy is to meet the desired system requirements, with the lowest value of the energy cost. This paper propose a hybrid power generation system suitable for remote area application and highlight the impact of surface waves on turbine design and performance, and the importance of understanding the site-specific wave conditions.

Keywords: marine current energy, tidal turbines, wave turbine, renewable energy, surface waves, hydraulic flume experiments, instantaneous wave phase

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Authors: Arshleen Kaur, Sarang Barbarwar, Madhusudan Hamirwasia

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Sustainable architecture is going to be the soul of construction in the near future, with building material as a vital link connecting sustainability to construction. The priority in Architecture has shifted from having a lesser negative footprint to having a positive footprint on Earth. The design has to be eco-centric as well as anthro-centric so as to attain its true purpose. Brick holds the same importance like a cell holds in one’s body. The study focuses on this basic building block with an experimental material and technique known as Module Assembled Specially to Conserve (MASC). The study explores the usage and construction of these modules in the construction of buildings. It also shows the impact assessment of the modules on the environment and its significance in reducing the carbon footprint of the construction industry. The aspects like cost-effectiveness, ease of working and reusability of MASC have been studied as well.

Keywords: anthro-centric, carbon footprint, eco-centric, sustainable

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Authors: Friday Godwin Okibe, Christian Chinweuba Onoyima, Edith Bolanle Agbaji, Victor Olatunji Ajibola

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Polymer-inorganic nanocomposites are presently impacting diverse areas, specifically in biomedical sciences. In this research, hydroxyapatite-sodium alginate has been prepared, and characterized, with emphasis on the influence of sodium alginate on its characteristics. In situ wet chemical precipitation method was used in the preparation. The prepared nanocomposite was characterized with Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), with image analysis, and X-Ray Diffraction (XRD). The FTIR study shows peaks characteristics of hydroxyapatite and confirmed formation of the nanocomposite via chemical interaction between sodium alginate and hydroxyapatite. Image analysis shows the nanocomposites to be of irregular morphologies which did not show significant change with increasing sodium alginate addition, while particle size decreased with increase in sodium alginate addition (359.46 nm to 109.98 nm). From the XRD data, both the crystallite size and degree of crystallinity also decreased with increasing sodium alginate composition (32.36 nm to 9.47 nm and 72.87% to 1.82% respectively), while the specific surface area and microstrain increased with increasing sodium alginate composition (0.0041 to 0.0139 and 58.99 m²/g to 201.58 m²/g respectively). The results show that the formulation with 50%wt of sodium alginate (HASA-50%wt), possess exceptional characteristics for biomedical applications such as drug delivery.

Keywords: nanocomposite, sodium alginate, hydroxyapatite, biomedical, FTIR, XRD, SEM

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Authors: Prasanjit Das, M. M. K. Khan, M. G. Rasul, Jie Wu, I. Youn

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Mineral scale formation is undoubtedly a more serious problem in the mineral industry than other process industries. To better understand scale growth and suppression, an experimental model is proposed in this study for supersaturated crystallised solutions commonly found in mineral process plants. In this experiment, surface crystallisation of potassium nitrate (KNO3) on the wall of the agitation tank and agitation effects on the scale growth and suppression are studied. The new quantitative scale suppression model predicts that at lower agitation speed, the scale growth rate is enhanced and at higher agitation speed, the scale suppression rate increases due to the increased flow erosion effect. A lab-scale agitation tank with and without baffles were used as a benchmark in this study. The fluid dynamic effects on scale growth and suppression in the agitation tank with three different size impellers (diameter 86, 114, 160 mm and model A310 with flow number 0.56) at various ranges of rotational speed (up to 700 rpm) and solution with different concentration (4.5, 4.75 and 5.25 mol/dm3) were investigated. For more elucidation, the effects of the different size of the impeller on wall surface scale growth and suppression rate as well as bottom settled scale accumulation rate are also discussed. Emphasis was placed on applications in the mineral industry, although results are also relevant to other industrial applications.

Keywords: agitation tank, crystallisation, impeller speed, scale

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Authors: Alaa Morsy, Youssef Ibrahim

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Earthquake is one of the most catastrophic events, which makes enormous harm to properties and human lives. As a piece of a safe building configuration, reinforced concrete walls are given in structures to decrease horizontal displacements under seismic load. Shear walls are additionally used to oppose the horizontal loads that might be incited by the impact of wind. Reinforced concrete walls in residential buildings might have openings that are required for windows in outside walls or for doors in inside walls or different states of openings due to architectural purposes. The size, position, and area of openings may fluctuate from an engineering perspective. Shear walls can encounter harm around corners of entryways and windows because of advancement of stress concentration under the impact of vertical or horizontal loads. The openings cause a diminishing in shear wall capacity. It might have an unfavorable impact on the stiffness of reinforced concrete wall and on the seismic reaction of structures. Finite Element Method using software package ‘ANSYS ver. 12’ becomes an essential approach in analyzing civil engineering problems numerically. Now we can make various models with different parameters in short time by using ANSYS instead of doing it experimentally, which consumes a lot of time and money. Finite element modeling approach has been conducted to study the effect of opening shape, size and position in RC wall with different thicknesses under axial and lateral static loads. The proposed finite element approach has been verified with experimental programme conducted by the researchers and validated by their variables. A very good correlation has been observed between the model and experimental results including load capacity, failure mode, and lateral displacement. A parametric study is applied to investigate the effect of opening size, shape, position on different reinforced concrete wall thicknesses. The results may be useful for improving existing design models and to be applied in practice, as it satisfies both the architectural and the structural requirements.

Keywords: Ansys, concrete walls, openings, out of plane behavior, seismic, shear wall

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Authors: Muhanad Al-Jubouri

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A local scour is the most important of the several scours impacting bridge performance and security. Even though scour is widespread in bridges, especially during flood seasons, the experimental tests could not be applied to many standard highway bridges. A computational fluid dynamics numerical model was used to solve the problem of calculating local scouring and deposition for non-cohesive silt and clear water conditions near single and double cylindrical piers with the effect of floating debris. When FLOW-3D software is employed with the Rang turbulence model, the Nilsson bed-load transfer equation and fine mesh size are considered. The numerical findings of single cylindrical piers correspond pretty well with the physical model's results. Furthermore, after parameter effectiveness investigates the range of outcomes based on predicted user inputs such as the bed-load equation, mesh cell size, and turbulence model, the final numerical predictions are compared to experimental data. When the findings are compared, the error rate for the deepest point of the scour is equivalent to 3.8% for the single pier example.

Keywords: local scouring, non-cohesive, clear water, computational fluid dynamics, turbulence model, bed-load equation, debris

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Authors: Khalida Douibi, Rodrigo Balp, Solène Le Bars

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In the medical field, applications related to human experiments are frequently linked to reduced samples size, which makes the training of machine learning models quite sensitive and therefore not very robust nor generalizable. This is notably the case in Brain-Computer Interface (BCI) studies, where the sample size rarely exceeds 20 subjects or a few number of trials. To address this problem, several resampling approaches are often used during the data preparation phase, which is an overly critical step in a data science analysis process. One of the naive approaches that is usually applied by data scientists consists in the transformation of the entire database before the resampling phase. However, this can cause model’ s performance to be incorrectly estimated when making predictions on unseen data. In this paper, we explored the effect of data leakage observed during our BCI experiments for device control through the real-time classification of SSVEPs (Steady State Visually Evoked Potentials). We also studied potential ways to ensure optimal validation of the classifiers during the calibration phase to avoid overfitting. The results show that the scaling step is crucial for some algorithms, and it should be applied after the resampling phase to avoid data leackage and improve results.

Keywords: data leackage, data science, machine learning, SSVEP, BCI, overfitting

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Authors: Igor V. Kuzminov

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According to its content, the proposed article is a collection of articles with comments and additions. All articles, in one way or another, have a connection with the Second Law of Thermodynamics. The content of the articles is given in a concise form. The articles were published in different journals at different times. Main topics are presented: gravity, biography of the Earth, physics of global warming-cooling cycles, multiverse. The articles are based on the laws of classical physics. Along the way, it should be noted that the Second Law of thermodynamics can be formulated as the Law of Matter Cooling. As it cools down, the processes of condensation, separation, and changes in the aggregate states of matter occur. In accordance with these changes, a picture of the world is being formed. Also, the main driving force of these processes is the inverse temperature dependence of the forces of gravity. As matter cools, the forces of gravity increase. The actions of these phenomena in the compartment form a picture of the world.

Keywords: gravitational forces, cooling of matter, inverse temperature dependence of gravitational forces, planetary model of the atom

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Authors: Amin Padash, Mehran Khodaparast, Saadat Khodaparast

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Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. Climate change is caused by factors such as biotic processes, variations in solar radiation received by Earth, plate tectonics, and volcanic eruptions. Certain human activities have also been identified as significant causes of recent climate change, often referred to as “Global Warming”. The ultimate goal of this paper is to determine how climate change affects the style of life and all of our activities. The paper focuses on what the effects of humans are on climate change and how communities can achieve sustainable development and use resources in a way that is good for the ecosystem and public. We opine Climate Change is a vital issue that can be called “Wicked Problem”. This paper attempts to address this wicked problem by COMPRAM Methodology as one of the possible solutions.

Keywords: climate change, COMPRAM, human influences, sustainable development, wicked problems

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Authors: Xin Chen, Moxiao Li, Xuechao Sun, Fei Ti, Shaobao Liu, Feng Xu, Tian Jian Lu

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The composite materials with pores have the characteristics of light weight, sound insulation, and heat insulation, and have broad prospects in many fields, including aerospace. In general, the stiffness of such composite is less than the stiffness of the matrix material, limiting their applications. In this paper, we establish a theoretical model to analyze the deformation mechanism of a nano-pore. The interface between the pores and matrix material is described by the Gurtin-Murdoch model. By considering scale effect related with current deformation, we estimate the effective mechanical properties (e.g., effective shear modulus and bulk modulus) of a composite with nano-pores. Due to the scale effect, the elastic field in the composite was changed and local hardening was observed around the nano-pore, and the effective shear modulus and effective bulk modulus were found to be a function of the surface energy. The effective shear modulus increase with the surface energy and decrease with the size of the nano-pores, and the effective bulk modulus decrease with the surface energy and increase with the size of the nano-pores. These results have potential applications in the nanocomposite mechanics and aerospace field.

Keywords: composite mechanics, nano-inhomogeneity, nano-pores, scale effect

Procedia PDF Downloads 128

Authors: G. Valentis, Q. Berthelot

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Nowadays the trend to develop ever more intelligent and autonomous systems often takes its inspiration in the living beings on Earth. Some simple isolated systems are able, once brought together, to form a strong and reliable system. When trying to adapt the idea to man-made systems it is not possible to include in their program everything the system may encounter during its life cycle. It is, thus, necessary to make the system able to take decisions based on other criteria such as its past experience, i.e. to make the system learn on its own. However, at some point the acquired knowledge depends also on environment. So the question is: if system environment is modified, how could the system respond to it quickly and appropriately enough? Here, starting from reinforcement learning to rate its decisions, and using adaptive learning algorithms for gain and loss reward, the system is made able to respond to changing environment and to adapt its knowledge as time passes. Application is made to a robot finding an exit in a labyrinth.

Keywords: reinforcement learning, neural network, autonomous systems, adaptive learning, changing environment

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Authors: Anastasia Beketova, Emmanouil-George C. Tzanakakis, Ioannis G. Tzoutzas, Eleana Kontonasaki

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In restorative dentistry, yttria-stabilized zirconia (YSZ) nanoparticles can be applied as fillers to improve the mechanical properties of various resin-based materials. Using sol-gel based synthesis as simple and cost-effective method, nano-sized YSZ particles with high purity can be produced. The aim of this study was to synthesize YSZ nanoparticles by the Pechini sol-gel method at different temperatures and to investigate their composition, structure, and morphology. YSZ nanopowders were synthesized by the sol-gel method using zirconium oxychloride octahydrate (ZrOCl₂.8H₂O) and yttrium nitrate hexahydrate (Y(NO₃)₃.6H₂O) as precursors with the addition of acid chelating agents to control hydrolysis and gelation reactions. The obtained powders underwent TG_DTA analysis and were sintered at three different temperatures: 800, 1000, and 1200°C for 2 hours. Their composition and morphology were investigated by Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction Analysis (XRD), Scanning Electron Microscopy with associated with Energy Dispersive X-ray analyzer (SEM-EDX), Transmission Electron Microscopy (TEM) methods, and Dynamic Light Scattering (DLS). FTIR and XRD analysis showed the presence of pure tetragonal phase in the composition of nanopowders. By increasing the calcination temperature, the crystallinity of materials increased, reaching 47.2 nm for the YSZ1200 specimens. SEM analysis at high magnifications and DLS analysis showed submicron-sized particles with good dispersion and low agglomeration, which increased in size as the sintering temperature was elevated. From the TEM images of the YSZ1000 specimen, it can be seen that zirconia nanoparticles are uniform in size and shape and attain an average particle size of about 50 nm. The electron diffraction patterns clearly revealed ring patterns of polycrystalline tetragonal zirconia phase. Pure YSZ nanopowders have been successfully synthesized by the sol-gel method at different temperatures. Their size is small, and uniform, allowing their incorporation of dental luting resin cements to improve their mechanical properties and possibly enhance the bond strength of demanding dental ceramics such as zirconia to the tooth structure. This research is co-financed by Greece and the European Union (European Social Fund- ESF) through the Operational Programme 'Human Resources Development, Education and Lifelong Learning 2014- 2020' in the context of the project 'Development of zirconia adhesion cements with stabilized zirconia nanoparticles: physicochemical properties and bond strength under aging conditions' (MIS 5047876).

Keywords: dental cements, nanoparticles, sol-gel, yttria-stabilized zirconia, YSZ

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Authors: Dalia M. Abouelfadl, Noha N. Yassen, Marwa E. Shabana

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Background: The evolution of immune therapy motivated many to study the relation between immune response and progression of cancer. Little is known about expression of PD-L1 (a newly evolving immunotherapeutic drug) in papillary thyroid carcinoma (PTC) arising de-novo and PTC arising on top of autoimmune thyroiditis (Hashimoto's (HT) and lymphocytic thyroiditis (LT)). The aim of this work is to study the alteration of expression of PD-L1 in PTCs arising from de-novo or on top of HT OR LT using immunohistochemistry and image analyser system. Method: 100 paraffin blocks for PTC cases were collected retrospectively for staining using PD-L1 rabbit monoclonal antibody (BIOCARE-ACI 3171 A, C). The antibody expression is measured digitally using Image Analyzer Leica Qwin 3000, and the membranous and cytoplasmic expression of PD-L1 in tumor cells was considered positive. The results were correlated with tumor grade, size, and LN status. Results: The study samples consisted of 41 cases of PTC arising De novo, 36 cases on top of HT, and 23 on top of LT. Expression of PD-L1 was highest among the PTC-HL group (25 case-69%) followed by PTC-TL group (14 case-60.8%) then de-novo PTC (19 case-46%) with P Value < 0.05. PD-L1 expression correlated with nodal metastasis and was not relevant to tumor size or grade. Conclusion: The severity of the immune response in tumor microenvironment directly influences PTC prognosis. The anti PD-L1 Ab can be a very successful therapeutic agent for PTC arising on top of HT.

Keywords: carcinoma, Hashimoto's, lymphocytic, papillary, PD-L1, thyroiditis

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Authors: Jaffar Hussain, Farman Ali Shah

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As we know that Pakistan is the developing country so it adopts new technologies for progress. In last three decays, some new technologies were introduced in the world in which Effective Microorganism was one of them. Microorganisms are one of the most power full living forces on earth. Originally, EM was developed as an odor control, farm, and animal health, human health many industrial treatments. Effective Microorganism is an organic fertilizer that contains a mixture of co-existing valuable microorganism composed from the environment. There are vast application of the EM in the world in which the researchers are explained in literature .In Pakistan work on EM technologies are under process, researcher are doing work to make them most valuable. At that time the application of EM are in agriculture, water treatment, to increase Cement strength, improving saline soil etc. Effective microorganisms are environmentally friendly , not-naturally organized, not chemically synthesized, not dangerous and not pathogenic.

Keywords: developing country, technologies, effective microorganism, researchers, Pakistan, agriculture

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Authors: Levente Varga, Dávid Deritei, Mária Ercsey-Ravasz, Răzvan Florian, Zsolt I. Lázár, István Papp, Ferenc Járai-Szabó

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One of the major shortcomings of widely used scientometric indicators is that different disciplines cannot be compared with each other. The issue of cross-disciplinary normalization has been long discussed, but even the classification of publications into scientific domains poses problems. Structural properties of citation networks offer new possibilities, however, the large size and constant growth of these networks asks for precaution. Here we present a new tool that in order to perform cross-field normalization of scientometric indicators of individual publications relays on the structural properties of citation networks. Due to the large size of the networks, a systematic procedure for identifying scientific domains based on a local community detection algorithm is proposed. The algorithm is tested with different benchmark and real-world networks. Then, by the use of this algorithm, the mechanism of the scientometric indicator normalization process is shown for a few indicators like the citation number, P-index and a local version of the PageRank indicator. The fat-tail trend of the article indicator distribution enables us to successfully perform the indicator normalization process.

Keywords: citation networks, cross-field normalization, local cluster detection, scientometric indicators

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Authors: K. Berhanu

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Improper land use results in land degradation and decline in agricultural productivity. Hence, in order to get maximum benefits out of land, proper utilization of its resources is inevitable. The present study was aimed at identifying the landcover changes in the study area in the last 25 years and determines the extent and direction of change that has occurred. The study made use of Landsat TM 1986 and 2011 Remote Sensing Satellite Image for analysis to determine the extent and pattern of rangeland change. The results of the landuse/landcover change detection showed that in the last 25 years, 3 major changes were observed, grassland and open shrub-land resource significantly decreased at a rate of 17.1km2/year and 12 km2/year/, respectively. On the other hand in 25 years dense bushland, open bush land, dense shrubland and cultivated land has shown increment in size at a rate of 0.23km2/year,13.5 km2/year, 6.3 km2/year and 0.2 km2/year, respectively within 25 years. The expansion of unpalatable woody species significantly reduced the rangeland size and availability of grasses. The consequence of the decrease in herbaceous biomass production might result in high risk of food insecurity in the area unless proper interventions are made in time.

Keywords: GIS and remote sensing, Dire District, land use/land cover, land sat TM

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Authors: Sospeter P. Maganga, Alphonce Wikedzi, Mussa D. Budeba, Samwel V. Manyele

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This study characterizes complex gold ores (elemental and mineralogical composition, gold distribution, ore grindability, and mineral liberation) for preliminary process selection. About 200 kg of ore samples were collected from each location using systematic sampling by mass interval. Ores were dried, crushed, milled, and split into representative sub-samples (about 1 kg) for elemental and mineralogical composition analyses using X-ray fluorescence (XRF), fire assay finished with Atomic Absorption Spectrometer (AAS), and X-ray Diffraction (XRD) methods, respectively. The gold distribution was studied on size-by-size fractions, while ore grindability was determined using the standard Bond test. The mineral liberation analysis was conducted using ThermoFisher Scientific Mineral Liberation Analyzer (MLA) 650, where unsieved polished grain mounts (80% passing 700 µm) were used as MLA feed. Two MLA measurement modes, X-ray modal analysis (XMOD) and sparse phase liberation-grain X-ray mapping analysis (SPL-GXMAP), were employed. At least two cyanide consumers (Cu, Fe, Pb, and Zn) and kinetics impeders (Mn, S, As, and Bi) were present in all locations investigated. Copper content at Kapanda (0.77% Cu) and Ibindi (7.48% Cu) exceeded the recommended threshold of 0.5% Cu for direct cyanidation. The gold ore at Ibindi indicated a higher rate of grinding compared to other locations. This could be explained by the highest grindability (2.119 g/rev.) and lowest Bond work index (10.213 kWh/t) values. The pyrite-marcasite, chalcopyrite, galena, and siderite were identified as major gold, copper, lead, and iron-bearing minerals, respectively, with potential for economic extraction. However, only gold and copper can be recovered under conventional milling because of grain size issues (galena is exposed by 10%) and process complexity (difficult to concentrate and smelt iron from siderite). Therefore, the preliminary process selection is copper flotation followed by gold cyanidation for Kapanda and Ibindi ores, whereas gold cyanidation with additives such as glycine or ammonia is selected for Mawemeru and Itumbi ores because of low concentrations of Cu, Pb, Fe, and Zn minerals.

Keywords: complex gold ores, mineral liberation, ore characterization, ore grindability

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Authors: Abdel Ghany F. Shoair, Mai M. A. H. Shanab

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The basic aqueous systems NiSO4.6H₂O / K₂S₂O₈ (PH= 14) or NiSO₄.6H₂O / KBrO₃ (PH = 11.5) were ‎investigated ‎for the ‎catalytic conversion benzyl alcohol and ‎some para-substituted benzyl ‎alcohols to their ‎corresponding ‎acids in 75-97 % yield at room ‎temperature. The active species ‎was isolated and characterized by scanning ‎electron ‎microscopy (SEM), ‎‎transmission electron microscopy (TEM), X-ray ‎powder diffraction, EDX and ‎‎FT-IR ‎techniques and identified as NiO₂ nanoparticles (NPNPs). The SEM and ‎TEM images of nickel peroxide samples show a fine spherical-like ‎aggregation of ‎NiO₂ molecules with a nearly homogeneous partial size and confirm the ‎aggregation's size ‎to ‎be in the range of 2-3 nm. The yields, turnover (TO) and turn ‎over frequencies (TOF) were calculated. ‎It was noticed ‎that the aromatic alcohols ‎containing para-substituted electron donation groups gave better ‎‎yields than ‎those having electron-withdrawing groups. The optimum conditions for this ‎‎catalytic reaction ‎were studied using benzyl alcohol as a model. The mechanism ‎of the ‎catalytic conversion reaction was ‎suggested, in which the produced ‎(NPNPs) convert alcohols ‎to acids in two steps through the formation of the ‎‎corresponding aldehyde. The produced ‎NiO, because of this conversion, is ‎converted again to (NPNPs) by ‎an excess of K₂S₂O₈ or KBrO₃. This ‎catalytic cycle continues ‎until all the substrate is oxidized.

Keywords: Nickel, oxidation, catalysts, benzyl alcohol

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Authors: Spoorthi Srupad

Abstract:

Environmental Impact Assessment (EIA) stands as a critical engineering application facilitated by Earth Resources and Environmental Remote Sensing. Employing advanced technologies, this process enables a systematic evaluation of potential environmental impacts arising from engineering projects. Remote sensing techniques, including satellite imagery and geographic information systems (GIS), play a pivotal role in providing comprehensive data for assessing changes in land cover, vegetation, water bodies, and air quality. This abstract delves into the significance of EIA in engineering, emphasizing its role in ensuring sustainable and environmentally responsible practices. The integration of remote sensing technologies enhances the accuracy and efficiency of impact assessments, contributing to informed decision-making and the mitigation of adverse environmental consequences associated with engineering endeavors.

Keywords: environmental impact assessment, engineering applications, sustainability, environmental monitoring, remote sensing, geographic information systems, environmental management

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Authors: Riddhi Trivedi, Shrenik Shah

Abstract:

For Si RNA to be delivered various biodegradable polymers are trialed by many researchers. One of them is Chitosan (CS) nanoparticles which have been extensively studied for siRNA delivery but the stability and efficacy of such particles are highly dependent on the types of cross-linker used. Hence the attempts are made in this study with PGA To address this issue, three common cross-linkers; Ethylene glycol diacrylate (ED) and poly-D-glutamic acid (PGA) were used to prepare siRNA loaded CS-ED/PGA nanoparticles by ionic gelation method. The nanoparticles which were obtained were compared for its characterization in terms of its physicochemical properties i.e. particle size of the resultant particles, zeta potential, its encapsulation capacity in the polymer. Among all the formulations prepared with different crosslinker PGA siRNA had the smallest particle size (ranged from 120 ± 1.7 to 500 ± 10.9 nm) with zeta potential ranged from 22.1 ± 1.5 to +32.4 ± 0.5 mV, and high entrapment ( > 91%) and binding efficiencies. Similarly, CS-ED nanoparticles showed better siRNA protection during storage at 4˚C and as determined by serum protection assay. TEM micrographs revealed the assorted morphology of CS-PGA-siRNA nanoparticles in contrast to irregular morphology displayed by CS-ED-siRNA. All siRNA loaded nanoparticles were found to give initial burst release which after some time followed by a sustained release of siRNA which were loaded inside. All the formulations showed concentration-dependent cytotoxicity with when cytotoxicity performed by HeLa and normal vero cell lines.

Keywords: chitosan, siRNA, cytotoxicity, cell line study

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Authors: Sari Aouatef, Larabi Amina

Abstract:

First-principles calculations within density functional theory based are used to investigate the influence of doped rare earth elements on some properties of perovskite systems Dy₀.₀₆₂₅Y₀.₉₃₇₅FeO₃ and Dy₀.₁₂₅ Y₀.₈₇₅ FeO₃. The electronic and magnetic properties are studied by means of the full-potential linearized augmented plane wave method with Vasp code. The calculated densities of states presented in this work identify the semiconducting behavior for Dy₀.₁₂₅ Y₀.₈₇₅ FeO₃, and the semi-metallic behavior for Dy₀.₀₆₂₅Y₀.₉₃₇₅ FeO₃. Besides, to investigate magnetic properties of several compounds, four magnetic configurations are considered (ferromagnetic (FM), antiferromagnetic type A (A-AFM), antiferromagnetic type C (C-AFM) and antiferromagnetic type G (G-AFM). By doping the Dy element, the system shows different changes in the magnetic order and electronic structure. It is found that Dy₀.₀₆₂₅Y₀.₉₃₇₅ FeO₃ exhibits the strongest magnetic change corresponding to the transition to the ferromagnetic order with the largest magnetic moment of 4.997.

Keywords: DFT, Perovskites, multiferroic, magnetic properties

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Authors: Ali A. Aldosari

Abstract:

Change detection of Earth surface features is extremely important for better understanding of our environment in order to promote better decision making. Al-Jawf is remarkable for its abundant agricultural water where there is fertile agricultural land due largely to underground water. As result, this region has large areas of cultivation of dates, olives and fruits trees as well as other agricultural products such as Alfa Alfa and wheat. However this agricultural area was declined due to the reduction of government supports in the last decade. This reduction was not officially recorded or measured in this region at large scale or governorate level. Remote sensing data are primary sources extensively used for change detection in agriculture applications. This study is applied the technology of GIS and used the Normalized Difference Vegetation Index (NDVI) which can be used to measure and analyze the spatial and temporal changes in the agriculture areas in the Aljouf region.

Keywords: spatial analysis, geographical information system, change detection

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Authors: Mehdi Asgarkhani

Abstract:

Today, investment on Information Technology (IT) solutions in most organizations is the largest component of capital expenditure. As capital investment on IT continues to grow, IT managers and strategists are expected to develop and put in practice effective decision making models (frameworks) that improve decision-making processes for the use of IT in organizations and optimize the investment on IT solutions. To be exact, there is an expectation that organizations not only maximize the benefits of adopting IT solutions but also avoid the many pitfalls that are associated with rapid introduction of technological change. Different organizations depending on size, complexity of solutions required and processes used for financial management and budgeting may use different techniques for managing strategic investment on IT solutions. Decision making processes for strategic use of IT within organizations are often referred to as IT Governance (or Corporate IT Governance). This paper examines IT governance - as a tool for best practice in decision making about IT strategies. Discussions in this paper represent phase I of a project which was initiated to investigate trends in strategic decision making on IT strategies. Phase I is concerned mainly with review of literature and a number of case studies, establishing that the practice of IT governance, depending on the complexity of IT solutions, organization's size and organization's stage of maturity, varies significantly – from informal approaches to sophisticated formal frameworks.

Keywords: IT governance, corporate governance, IT governance frameworks, IT governance components, aligning IT with business strategies

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Authors: Shila Khayambashi

Abstract:

For the past few decades, Western researchers studied different youth issues, such as bullying, peer-aggression, depression, self-harm, and suicide, in a formulated and standardized manner. These researchers have grounded their studies upon a series of introduced characteristics and traits, which pragmatically defined the action of the individuals involved in these activities (Olweus, 1994). The phenomena of bullying and peer-aggression have touched the lives of many immigrant youths, as well. However, in the case of these immigrant young adults, the Police investigated, and later dismissed, the victims’ involvement in drugs and gangs’ activities, instead of questioning the possibility of the peer-aggression. This paper argues that neither government officials nor school personnel has ever investigated any cyber-documentation which would clarify these youth’s untimely deaths or search for any indication of peer-aggression at school. Through my ongoing research, I will problematize the Eurocentric definition of bullying and its limitations. I question the assumed universality of these definitions’ characteristics and their lack of minority representation. This research questions explicitly the positionality of the displaced youth within the promised multiculturality of Canada. I will ask: Does one size fit all, considering the bio-psycho-socio-economic differences between the Eastern and the Western worlds? More importantly, how does the epidemy of the communicative devices, like smartphones, and communicative apps, like Twitter and Snapchats, facilitate or hinder peer-aggression for the displaced youths?

Keywords: Bullying , Immigrant youths, Peer aggression, Minority population

Procedia PDF Downloads 129