Search results for: galaxy formation and evolution
Commenced in January 2007
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Edition: International
Paper Count: 5004

Search results for: galaxy formation and evolution

4644 Ideal Posture in Regulating Legal Regulations in Indonesia

Authors: M Jeffri Arlinandes Chandra, Puwaningdyah Murti Wahyuni, Dewi Mutiara M Jeffri Arlinandes Chandra, Puwaningdyah Murti Wahyuni, Dewi Mutiara

Abstract:

Indonesia is a state of the law in accordance with article 1 paragraph 3 of the Constitution of the Republic of Indonesia (1945 Constitution), namely, 'the State of Indonesia is a state of law'. The consequences of the rule of law are making the law as the main commanding officer or making the law as a basis for carrying out an action taken by the state. The types of regulations and procedures for the formation of legislation in Indonesia are contained in Law Number 12 of 2011 concerning the Formation of Legislation. Various attempts were made to make quality regulations both in the formal hierarchy and material hierarchy such as synchronization and harmonization in the formation of laws and regulations so that there is no conflict between equal and hierarchical laws, but the fact is that there are still many conflicting regulations found between one another. This can be seen clearly in the many laws and regulations that were sued to judicial institutions such as the Constitutional Court (MK) and the Supreme Court (MA). Therefore, it is necessary to have a formulation regarding the governance of the formation of laws and regulations so as to minimize the occurrence of lawsuits to the court so that positive law can be realized which can be used today and for the future (ius constituendum). The research method that will be used in this research is a combination of normative research (library research) supported by empirical data from field research so that it can formulate concepts and answer the challenges being faced. First, the structuring of laws and regulations in Indonesia must start from the inventory of laws and regulations, whether they can be classified based on the type of legislation, what are they set about, the year of manufacture, etc. so that they can be clearly traced to the regulations relating to the formation of laws and regulations. Second, the search and revocation/revocation of laws and regulations that do not exist in the state registration system. Third, the periodic evaluation system is carried out at every level of the hierarchy of laws and regulations. These steps will form an ideal model of laws and regulations in Indonesia both in terms of content and material so that the instructions can be codified and clearly inventoried so that they can be accessed by the wider community as a concrete manifestation of the principle that all people know the law (presumptio iures de iure).

Keywords: legislation, review, evaluation, reconstruction

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4643 Tailorability of Poly(Aspartic Acid)/BSA Complex by Self-Assembling in Aqueous Solutions

Authors: Loredana E. Nita, Aurica P. Chiriac, Elena Stoleru, Alina Diaconu, Tudorachi Nita

Abstract:

Self-assembly processes are an attractive method to form new and complex structures between macromolecular compounds to be used for specific applications. In this context, intramolecular and intermolecular bonds play a key role during self-assembling processes in preparation of carrier systems of bioactive substances. Polyelectrolyte complexes (PECs) are formed through electrostatic interactions, and though they are significantly below of the covalent linkages in their strength, these complexes are sufficiently stable owing to the association processes. The relative ease way of PECs formation makes from them a versatile tool for preparation of various materials, with properties that can be tuned by adjusting several parameters, such as the chemical composition and structure of polyelectrolytes, pH and ionic strength of solutions, temperature and post-treatment procedures. For example, protein-polyelectrolyte complexes (PPCs) are playing an important role in various chemical and biological processes, such as protein separation, enzyme stabilization and polymer drug delivery systems. The present investigation is focused on evaluation of the PPC formation between a synthetic polypeptide (poly(aspartic acid) – PAS) and a natural protein (bovine serum albumin - BSA). The PPC obtained from PAS and BSA in different ratio was investigated by corroboration of various techniques of characterization as: spectroscopy, microscopy, thermo-gravimetric analysis, DLS and zeta potential determination, measurements which were performed in static and/or dynamic conditions. The static contact angle of the sample films was also determined in order to evaluate the changes brought upon surface free energy of the prepared PPCs in interdependence with the complexes composition. The evolution of hydrodynamic diameter and zeta potential of the PPC, recorded in situ, confirm changes of both co-partners conformation, a 1/1 ratio between protein and polyelectrolyte being benefit for the preparation of a stable PPC. Also, the study evidenced the dependence of PPC formation on the temperature of preparation. Thus, at low temperatures the PPC is formed with compact structure, small dimension and hydrodynamic diameter, close to those of BSA. The behavior at thermal treatment of the prepared PPCs is in agreement with the composition of the complexes. From the contact angle determination results the increase of the PPC films cohesion, which is higher than that of BSA films. Also, a higher hydrophobicity corresponds to the new PPC films denoting a good adhesion of the red blood cells onto the surface of PSA/BSA interpenetrated systems. The SEM investigation evidenced as well the specific internal structure of PPC concretized in phases with different size and shape in interdependence with the interpolymer mixture composition.

Keywords: polyelectrolyte – protein complex, bovine serum albumin, poly(aspartic acid), self-assembly

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4642 Mapping Tunnelling Parameters for Global Optimization in Big Data via Dye Laser Simulation

Authors: Sahil Imtiyaz

Abstract:

One of the biggest challenges has emerged from the ever-expanding, dynamic, and instantaneously changing space-Big Data; and to find a data point and inherit wisdom to this space is a hard task. In this paper, we reduce the space of big data in Hamiltonian formalism that is in concordance with Ising Model. For this formulation, we simulate the system using dye laser in FORTRAN and analyse the dynamics of the data point in energy well of rhodium atom. After mapping the photon intensity and pulse width with energy and potential we concluded that as we increase the energy there is also increase in probability of tunnelling up to some point and then it starts decreasing and then shows a randomizing behaviour. It is due to decoherence with the environment and hence there is a loss of ‘quantumness’. This interprets the efficiency parameter and the extent of quantum evolution. The results are strongly encouraging in favour of the use of ‘Topological Property’ as a source of information instead of the qubit.

Keywords: big data, optimization, quantum evolution, hamiltonian, dye laser, fermionic computations

Procedia PDF Downloads 192
4641 A Study of the Interactions between the Inter-City Traffic System and the Spatial Structure Evolution in the Yangtze River Delta from Time and Space Dimensions

Authors: Zhang Cong, Cai Runlin, Jia Fengjiao

Abstract:

The evolution of the urban agglomeration spatial structure requires strong support of the inter-city traffic system. And the inter-city traffic system can not only meet the demand of the urban agglomeration transportation but also guide the economic development. To correctly understand the relationship between inter-city traffic planning and urban agglomeration can help the urban agglomeration coordinated developing with the inter-city traffic system. The Yangtze River Delta is one of the most representative urban agglomerations in China with strong economic vitality, high city levels, diversified urban space form, and improved transport infrastructure. With the promotion of industrial division in the Yangtze River Delta and the regional travel facilitation brought by inter-city traffic, the urban agglomeration is characterized by highly increasing of inter-city transportation demand, the urbanization of regional traffic, adjacent regional transportation links breaking administrative boundaries, the networked channels and so on. Therefore, the development of inter-city traffic system presents new trends and challenges. This paper studies the interactions between inter-city traffic system and regional economic growth, regional factor flow, and regional spatial structure evolution in the Yangtze River Delta from two dimensions of time and space. On this basis, the adaptability of inter-city traffic development mode and urban agglomeration space structure is analyzed. First of all, the coordination between urban agglomeration planning and inter-city traffic planning is judged from the planning level. Secondly, the coordination between inter-city traffic elements and industries and population distributions is judged from the perspective of space. Finally, the coordination of the cross-regional planning and construction of inter-city traffic system is judged. The conclusions can provide an empirical reference for intercity traffic planning in Yangtze River Delta region and other urban agglomerations, and it is also of great significance to optimize the allocation of urban agglomerations and the overall operational efficiency.

Keywords: evolution, interaction, inter-city traffic system, spatial structure

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4640 The Effect of Combustion Chamber Deposits (CCD) on Homogeneous Change Compression Ignition (HCCI)

Authors: Abdulmagid A. Khattabi, Ahmed A. Hablus, Osama Ab. M. Shafah

Abstract:

The goal of this work is to understand how the thermal influence of combustion chamber deposits can be utilized to expand the operating range of HCCI combustion. In order to do this, two main objectives must first be met; tracking deposit formation trends in an HCCI engine and determining the sensitivity of HCCI combustion to CCD. This requires testing that demonstrates the differences in combustion between a clean engine and one with deposits coating the chamber. This will involve a long-term test that tracks the effects of CCD on combustion. The test will start with a clean engine. One baseline HCCI operating point is maintained for the duration of the test during which gradual combustion chamber deposit formation will occur. Combustion parameters, including heat release rates and emissions will be tracked for the duration and compared to the case of a clean engine. This work will begin by detailing the specifics of the test procedure and measurements taken throughout the test. Then a review of the effects of the gradual formation of deposits in the engine will be given.

Keywords: fuels, fuel atomization, pattern factor, alternate fuels combustion, efficiency gas turbine combustion, lean blow out, exhaust and liner wall temperature

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4639 Nanoprofiling of GaAs Surface in a Combined Low-Temperature Plasma for Microwave Devices

Authors: Victor S. Klimin, Alexey A. Rezvan, Maxim S. Solodovnik, Oleg A. Ageev

Abstract:

In this paper, the problems of existing methods of profiling and surface modification of nanoscale arsenide-gallium structures are analyzed. The use of a combination of methods of local anodic oxidation and plasma chemical etching to solve this problem is considered. The main features that make this technology one of the promising areas of modification and profiling of near-surface layers of solids are demonstrated. In this paper, we studied the effect of formation stress and etching time on the geometrical parameters of the etched layer and the roughness of the etched surface. Experimental dependences of the thickness of the etched layer on the time and stress of formation were obtained. The surface analysis was carried out using atomic force microscopy methods, the corresponding profilograms were constructed from the obtained images, and the roughness of the etched surface was studied accordingly. It was shown that at high formation voltage, the depth of the etched surface increased, this is due to an increase in the number of active particles (oxygen ions and hydroxyl groups) formed as a result of the decomposition of water molecules in an electric field, during the formation of oxide nanostructures on the surface of gallium arsenide. Oxide layers were used as negative masks for subsequent plasma chemical etching by the STE ICPe68 unit. BCl₃ was chosen as the chlorine-containing gas, which differs from analogs in some parameters for the effect of etching of nanostructures based on gallium arsenide in the low-temperature plasma. The gas mixture of reaction chamber consisted of a buffer gas NAr = 100 cm³/min and a chlorine-containing gas NBCl₃ = 15 cm³/min at a pressure P = 2 Pa. The influence of these methods modes, which are formation voltage and etching time, on the roughness and geometric parameters, and corresponding dependences are demonstrated. Probe nanotechnology was used for surface analysis.

Keywords: nanostructures, GaAs, plasma chemical etching, modification structures

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4638 Unicellular to Multicellular: Some Empirically Parsimoniously Plausible Hypotheses

Authors: Catherine K. Derow

Abstract:

Possibly a slime mold somehow mutated or already was mutated at progeniture and so stayed as a metazoan when it developed into the fruiting stage and so the slime mold(s) we are evolved and similar to are genetically differ from the slime molds in existence now. This may be why there are genetic links between humans and other metazoa now alive and slime molds now alive but we are now divergent branches of the evolutionary tree compared to the original slime mold, or perhaps slime mold-like organisms, that gave rise to metazoan animalia and perhaps algae and plantae as slime molds were undifferentiated enough in many ways that could allow their descendants to evolve into these three separate phylogenetic categories. Or it may be a slime mold was born or somehow progenated as multicellular, as the particular organism was mutated enough to have say divided in a a 'pseudo-embryonic' stage, and this could have happened for algae, plantae as well as animalia or all the branches may be from the same line but the missing link might be covered in 'phylogenetic sequence comparison noise'.

Keywords: metazoan evolution, unicellular bridge to metazoans, evolution, slime mold

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4637 Microstructural Characterization of Creep Damage Evolution in Welded Inconel 600 Superalloy

Authors: Lourdes Yareth Herrera-Chavez, Alberto Ruiz, Victor H. Lopez

Abstract:

Superalloys are used in components that operate at high temperatures such as pressure vessels and heat exchanger tubing. Design standards for these components must consider creep resistance among other criteria. Fusion welding processes are commonly used in the industry to join such components. Fusion processes commonly generate three distinctive zones, i.e. heat affected zone (HAZ), namely weld metal (WM) and base metal (BM). In nickel-based superalloy, the microstructure developed during fusion welding dictates the mechanical response of the welded component and it is very important to establish these effects in the mechanical response of the component. In this work, two plates of Inconel 600 superalloy were Gas Metal Arc Welded (GMAW). Creep samples were cut and milled to specifications and creep tested at a temperature (650 °C) using stress level of 350, 300, 275, 250 and 200 MPa. Microstructural analysis results showed a progressive creep damage evolution that depends on the stress levels with a preferential accumulation of creep damage at the heat affected zone where the creep rupture preferentially occurs owing to an austenitic matrix with grain boundary precipitated of the type Cr23C6. The fractured surfaces showed dimple patterns of cavity and voids. Results indicated that the damage mechanism is due to cavity growth by the combined effect of the power law and diffusion creep.

Keywords: austenitic microstructure, creep damage evolution, heat affected zone, vickers microhardness

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4636 Influence of Sr(BO2)2 Doping on Superconducting Properties of (Bi,Pb)-2223 Phase

Authors: N. G. Margiani, I. G. Kvartskhava, G. A. Mumladze, Z. A. Adamia

Abstract:

Chemical doping with different elements and compounds at various amounts represents the most suitable approach to improve the superconducting properties of bismuth-based superconductors for technological applications. In this paper, the influence of partial substitution of Sr(BO2)2 for SrO on the phase formation kinetics and transport properties of (Bi,Pb)-2223 HTS has been studied for the first time. Samples with nominal composition Bi1.7Pb0.3Sr2-xCa2Cu3Oy[Sr(BO2)2]x, x=0, 0.0375, 0.075, 0.15, 0.25, were prepared by the standard solid state processing. The appropriate mixtures were calcined at 845 oC for 40 h. The resulting materials were pressed into pellets and annealed at 837 oC for 30 h in air. Superconducting properties of undoped (reference) and Sr(BO2)2-doped (Bi,Pb)-2223 compounds were investigated through X-ray diffraction (XRD), resistivity (ρ) and transport critical current density (Jc) measurements. The surface morphology changes in the prepared samples were examined by scanning electron microscope (SEM). XRD and Jc studies have shown that the low level Sr(BO2)2 doping (x=0.0375-0.075) to the Sr-site promotes the formation of high-Tc phase and leads to the enhancement of current carrying capacity in (Bi,Pb)-2223 HTS. The doped sample with x=0.0375 has the best performance compared to other prepared samples. The estimated volume fraction of (Bi,Pb)-2223 phase increases from ~25 % for reference specimen to ~70 % for x=0.0375. Moreover, strong increase in the self-field Jc value was observed for this dopant amount (Jc=340 A/cm2), compared to an undoped sample (Jc=110 A/cm2). Pronounced enhancement of superconducting properties of (Bi,Pb)-2223 superconductor can be attributed to the acceleration of high-Tc phase formation as well as the improvement of inter-grain connectivity by small amounts of Sr(BO2)2 dopant.

Keywords: bismuth-based superconductor, critical current density, phase formation, Sr(BO₂)₂ doping

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4635 Virtual Practical Work as Formation of Physics Concept for Student

Authors: Sepdiana W. Rahmawati, Santi A. P. Anggraini

Abstract:

The world of education has made progress with the various new technologies with help of computer. No exception physics education, especially virtual physics practical work. By doing practical work, memory of physics concept will be more advantageous for student and they will understand the essence of actual physics, not only spiked formula. With help of computers, created a variety of applications that can be used by students to perform virtual practical work and students will start thinking systematically to be able find its own concepts and understand the application of physics.

Keywords: essence of physics, formation concept, physics concept, virtual practical work

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4634 Soot Formation in the Field of Combustion

Authors: Nacira Mecheri, N. Boussid

Abstract:

A new chemical mechanism designed to study the process of forming the first aromatic ring (benzene) and polycyclic aromatic hydrocarbons (PAH) from a flame of acetylene (C2H2) has been developed. The mechanism developed, contains 50 chemical species involved in 268 reversible elementary reactions. The comparison between the results from modelling and experimental measurements allowed us to test the validity of the postulated mechanism in specific experimental conditions. Kinetic analysis of the flame by calculating the maximum rates for each elementary reaction, allowed us to identify key reactions pathways of consumption and formation of main precursors of soot.

Keywords: benzene, PAH, acetylene, modeling, flame, soot

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4633 Reversible and Irreversible Wrinkling in Tube Hydroforming Process

Authors: Ali Abd El-Aty, Ahmed Tauseef, Ahmad Farooq

Abstract:

This research aims at analyzing and optimizing the hydroforming process parameters to achieve a sound bulged tube without failure. Theoretical constitutive model is formulated to develop a working diagram including process window, which represents the optimize region to carry out the hydroforming process and predict the type of tube failure during the process accurately. The model is applied into different bulging ratios for low carbon steel (C1010). From this study, it is concluded that the tubes with bulging ratios up to 50% and 70% are successfully formed without defects. The tubes with bulging ratio of 90% are successfully formed by hydroforming with optimized the loading path (axial feed versus internal pressure) within the process window. The working diagram is modified due to different types of formation of wrinkling during the hydroforming process. The formation of wrinkles with increasing axial feed can be useful in terms of the achievement of higher bulging ratio and/or less thinning and this type of wrinkles can be overcome through the internal pressure in the later stage of the hydroforming process. On the other hand, the formation of wrinkles may be harmful, if it cannot be reversed.

Keywords: finite element, hydroforming, process window, wrinkling

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4632 Petrologic and Geochemical Characteristics of Marine Sand Strip in the Proterozoic Chuanlinggou Formation of the North China

Authors: Yue Feng, Chun-jiang Wang, Zhi-long Huang

Abstract:

The study of the sedimentary environment of Mesoproterozoic marine deposits in North China has attracted special attention in recent years. It is not clear that the sedimentary environment and the cause of formation of the sandstone strip and its internal carbonate cements and pyrite in the Mesoproterozoic Chuanlinggou Formation in North China. In this study, drilling core samples in North China were identified by microscopy, and their petrological characteristics such as mineral composition and structure were identified. The geochemical data of carbon and oxygen isotopes, total organic carbon (TOC) contents and total sulfur (TS) contents were obtained by processing and analyzing the samples. The samples are mainly quartz particles with low compositional maturity, combined with low value of TOC, it shows that the sedimentary environment of the sandy clastic is a sandy littoral sedimentary environment with relative strong hydrodynamic force, and then the sandstone strip in black shale are formed by the deposition of gravity flow. Analysis of TS values reflect sandstone bands formed in hypoxic environments. The carbonate cements and the pyrite in the sandstone belt are authigenic. The carbon isotope values of authigenic carbonate cements are negatively biased in comparison with the carbonate isotope of carbonate rocks in the same period, but it is more biased than the carbon isotopic values of anaerobic oxidation of methane (AOM) genetic carbonate rocks. Authigenic pyrite may be mainly due to the formation of HS- by the action of bacterial sulfate reduction (BSR) and Fe²⁺, their causes are in contact. This indicates that authigenic carbonate cements are mainly carbonate precipitates formed but are significantly affected by the effects of AOM. Summary, the sedimentary environment of the sandstone zone in the Chuanlinggou Formation in the North China is a shallow sea facies with iron rich and anoxic.

Keywords: sandstone strip, sedimentary environment, authigenic carbonate cements, authigenic pyrite, The Chuanlinggou group, North China

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4631 Reduction Shrinkage of Concrete without Use Reinforcement

Authors: Martin Tazky, Rudolf Hela, Lucia Osuska, Petr Novosad

Abstract:

Concrete’s volumetric changes are natural process caused by silicate minerals’ hydration. These changes can lead to cracking and subsequent destruction of cementitious material’s matrix. In most cases, cracks can be assessed as a negative effect of hydration, and in all cases, they lead to an acceleration of degradation processes. Preventing the formation of these cracks is, therefore, the main effort. Once of the possibility how to eliminate this natural concrete shrinkage process is by using different types of dispersed reinforcement. For this application of concrete shrinking, steel and polymer reinforcement are preferably used. Despite ordinarily used reinforcement in concrete to eliminate shrinkage it is possible to look at this specific problematic from the beginning by itself concrete mix composition. There are many secondary raw materials, which are helpful in reduction of hydration heat and also with shrinkage of concrete during curing. The new science shows the possibilities of shrinkage reduction also by the controlled formation of hydration products, which could act by itself morphology as a traditionally used dispersed reinforcement. This contribution deals with the possibility of controlled formation of mono- and tri-sulfate which are considered like degradation minerals. Mono- and tri- sulfate's controlled formation in a cementitious composite can be classified as a self-healing ability. Its crystal’s growth acts directly against the shrinking tension – this reduces the risk of cracks development. Controlled formation means that these crystals start to grow in the fresh state of the material (e.g. concrete) but stop right before it could cause any damage to the hardened material. Waste materials with the suitable chemical composition are very attractive precursors because of their added value in the form of landscape pollution’s reduction and, of course, low cost. In this experiment, the possibilities of using the fly ash from fluidized bed combustion as a mono- and tri-sulphate formation additive were investigated. The experiment itself was conducted on cement paste and concrete and specimens were subjected to a thorough analysis of physicomechanical properties as well as microstructure from the moment of mixing up to 180 days. In cement composites, were monitored the process of hydration and shrinkage. In a mixture with the used admixture of fluidized bed combustion fly ash, possible failures were specified by electronic microscopy and dynamic modulus of elasticity. The results of experiments show the possibility of shrinkage concrete reduction without using traditionally dispersed reinforcement.

Keywords: shrinkage, monosulphates, trisulphates, self-healing, fluidized fly ash

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4630 Sustainable Production of Tin Oxide Nanoparticles: Exploring Synthesis Techniques, Formation Mechanisms, and Versatile Applications

Authors: Yemane Tadesse Gebreslassie, Henok Gidey Gebretnsae

Abstract:

Nanotechnology has emerged as a highly promising field of research with wide-ranging applications across various scientific disciplines. In recent years, tin oxide has garnered significant attention due to its intriguing properties, particularly when synthesized in the nanoscale range. While numerous physical and chemical methods exist for producing tin oxide nanoparticles, these approaches tend to be costly, energy-intensive, and involve the use of toxic chemicals. Given the growing concerns regarding human health and environmental impact, there has been a shift towards developing cost-effective and environmentally friendly processes for tin oxide nanoparticle synthesis. Green synthesis methods utilizing biological entities such as plant extracts, bacteria, and natural biomolecules have shown promise in successfully producing tin oxide nanoparticles. However, scaling up the production to an industrial level using green synthesis approaches remains challenging due to the complexity of biological substrates, which hinders the elucidation of reaction mechanisms and formation processes. Thus, this review aims to provide an overview of the various sources of biological entities and methodologies employed in the green synthesis of tin oxide nanoparticles, as well as their impact on nanoparticle properties. Furthermore, this research delves into the strides made in comprehending the mechanisms behind the formation of nanoparticles as documented in existing literature. It also sheds light on the array of analytical techniques employed to investigate and elucidate the characteristics of these minuscule particles.

Keywords: nanotechnology, tin oxide, green synthesis, formation mechanisms

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4629 Psychological Aspects in the Doctrine of Dependent Origination

Authors: Sanjoy Barua Chowdhury

Abstract:

This research is an attempt to examine psychological aspect of the Buddha’s most cardinal and fundamental doctrine of Dependent Origination (paṭiccasamuppāda) along with drawing out a clear picture of the constituents from the law of causation and analyzes the mental states and motivational factors behind each constituent among twelvefold links. Meticulous research into the doctrine of Dependent Origination reveals how the main links from the doctrine of dependent origination provide a framework for psychological analysis through volitional formation (saṅkhāra), consciousness (viññāna), mentality and materiality (nāma-rūpa), contact (phassa), feeling (vedanā), craving (tanhā) and clinging (upādāna). This paper further illustrates the notion of perception (saññā) which can be found in the function of volitional formation (saṅkhāra) - a contributing factor, according to modern psychology, in the role of understanding human (puggala) motivation. The psychological analysis of dependent origination expounds the concept of personality highlighting present existence through the inter-relationship of the five faculties (pañcaupadānakkhandhā), viz., form (rūpa), feeling (vedanā), perception (saññā), volitional formation (saṅkhārā) and consciousness (viññāṇa).

Keywords: dependent origination, perception, motivational factors, feelings

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4628 Grain Structure Evolution during Friction-Stir Welding of 6061-T6 Aluminum Alloy

Authors: Aleksandr Kalinenko, Igor Vysotskiy, Sergey Malopheyev, Sergey Mironov, Rustam Kaibyshev

Abstract:

From a thermo-mechanical standpoint, friction-stir welding (FSW) represents a unique combination of very large strains, high temperature and relatively high strain rate. The material behavior under such extreme deformation conditions is not studied well and thus, the microstructural examinations of the friction-stir welded materials represent an essential academic interest. Moreover, a clear understanding of the microstructural mechanisms operating during FSW should improve our understanding of the microstructure-properties relationship in the FSWed materials and thus enables us to optimize their service characteristics. Despite extensive research in this field, the microstructural behavior of some important structural materials remains not completely clear. In order to contribute to this important work, the present study was undertaken to examine the grain structure evolution during the FSW of 6061-T6 aluminum alloy. To provide an in-depth insight into this process, the electron backscatter diffraction (EBSD) technique was employed for this purpose. Microstructural observations were conducted by using an FEI Quanta 450 Nova field-emission-gun scanning electron microscope equipped with TSL OIMTM software. A suitable surface finish for EBSD was obtained by electro-polishing in a solution of 25% nitric acid in methanol. A 15° criterion was employed to differentiate low-angle boundaries (LABs) from high-angle boundaries (HABs). In the entire range of the studied FSW regimes, the grain structure evolved in the stir zone was found to be dominated by nearly-equiaxed grains with a relatively high fraction of low-angle boundaries and the moderate-strength B/-B {112}<110> simple-shear texture. In all cases, the grain-structure development was found to be dictated by an extensive formation of deformation-induced boundaries, their gradual transformation to the high-angle grain boundaries. Accordingly, the grain subdivision was concluded to the key microstructural mechanism. Remarkably, a gradual suppression of this mechanism has been observed at relatively high welding temperatures. This surprising result has been attributed to the reduction of dislocation density due to the annihilation phenomena.

Keywords: electron backscatter diffraction, friction-stir welding, heat-treatable aluminum alloys, microstructure

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4627 Evolution of Germany’s Feed-in Tariff Policy

Authors: Gaafar Muhammed, N. T. Ersoy

Abstract:

The role of electricity in the economic development of any country is undeniable. The main goal of utilizing renewable sources in electricity generation, especially in the emerging countries, is to improve electricity access, economic development and energy sustainability. Germany’s recent transition from conventional to renewable energy technologies is overwhelming, this might not be associated with its abundant natural resources but owing to the policies in place. In line with the fast economic and technological developments recorded in recent years, Germany currently produces approximately 1059 GW of its energy from renewable sources. Hence, at the end of 2016, Germany is among the world leaders in terms of installed renewable energy capacity. As one of the most important factors that lead to renewable energy utilization in any nation is an effective policy, this study aims at examining the effect of policies on renewable energy (RE) development in Germany. Also, the study will focus on the evolution of the adopted feed-in tariff policies, as this evolution has affected the renewable energy capacity in Germany over a period of 15 years (2000 to 2015). The main contribution of the study is to establish a link between the feed-in tariff and the increase of RE in Germany’s energy mix. This is done by analyzing the characteristics of various feed-in tariff mechanisms adopted through the years. These characteristics include the feed-in-tariff rate, degression, special conditions, supported technology, etc. Then, the renewable energy development in Germany has been analyzed through the years along with the targets and the progress in reaching these targets. The study reveals that Germany’s renewable energy support policies (especially feed-in tariff) lead to several benefits and contribute towards the targets existing for renewable energy.

Keywords: feed-in tariff, Germany, policy, penewable energy

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4626 Characterization of the Pore System and Gas Storage Potential in Unconventional Reservoirs: A Case of Study of the Cretaceous la Luna Formation, Middle Magdalena Valley Basin, Colombia

Authors: Carlos Alberto Ríos-Reyes, Efraín Casadiego-Quintero

Abstract:

We propose a generalized workflow for mineralogy investigation of unconventional reservoirs using multi-scale imaging and pore-scale analyses. This workflow can be used for the integral evaluation of these resources. The Cretaceous La Luna Formation´s mudstones in the Middle Magdalena Valley Basin (Colombia) inherently show a heterogeneous pore system with organic and inorganic pores. For this reason, it is necessary to carry out the integration of high resolution 2D images of mapping by conventional petrography, scanning electron microscopy and quantitative evaluation of minerals by scanning electron microscopy to describe their organic and inorganic porosity to understand the transport mechanism through pores. The analyzed rocks show several pore types, including interparticle pores, organoporosity, intraparticle pores, intraparticle pores, and microchannels and/or microfractures. The existence of interconnected pores in pore system of these rocks promotes effective pathways for primary gas migration and storage space for residual hydrocarbons in mudstones, which is very useful in this type of gas reservoirs. It is crucial to understand not only the porous system of these rocks and their mineralogy but also to project the gas flow in order to design the appropriate strategies for the stimulation of unconventional reservoirs. Keywords: mudstones; La Luna Formation; gas storage; migration; hydrocarbon.

Keywords: mudstones, La luna formation, gas storage, migration, hydrocarbon

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4625 Diachronic Evolution and Multifaceted Interpretation of City-Mountain Landscape Culture: From Ritualistic Divinity to Poetic Aesthetics

Authors: Junjie Fu

Abstract:

This paper explores the cultural evolution of the "city-mountain" landscape in ancient Chinese cities, tracing its origins in the regional mountain and town division within the national system. It delves into the cultural archetype of "city-mountain" landscape divine imagery and its spatial characteristics, drawing from the spatial conception of mountain worship and divine order in the model of Kunlun and Penglai. Furthermore, it examines the shift from religious to daily life influences, leading to a poetic aesthetic turn in the "city-mountain" landscape. The paper also discusses the organizational structure of the "city-mountain" poetic landscape and its role as a space for enjoyment. By studying the cultural connotations, evolving relationships, and power mechanisms of the "city-mountain" landscape, this research provides theoretical insights for the construction and development of "city-mountain" landscapes and mountain cities.

Keywords: city-mountain landscape, cultural image, divinity, landscape image, poetry

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4624 Analyzing the Evolution of Polythiophene Nanoparticles Optically, Structurally, and Morphologically as a Sers (Surface-Enhanced Raman Spectroscopy) Sensor Pb²⁺ Detection in River Water

Authors: Temesgen Geremew

Abstract:

This study investigates the evolution of polythiophene nanoparticles (PThNPs) as surface-enhanced Raman spectroscopy (SERS) sensors for Pb²⁺ detection in river water. We analyze the PThNPs' optical, structural, and morphological properties at different stages of their development to understand their SERS performance. Techniques like UV-Vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) are employed for characterization. The SERS sensitivity towards Pb²⁺ is evaluated by monitoring the peak intensity of a specific Raman band upon increasing metal ion concentration. The study aims to elucidate the relationship between the PThNPs' characteristics and their SERS efficiency for Pb²⁺ detection, paving the way for optimizing their design and fabrication for improved sensing performance in real-world environmental monitoring applications.

Keywords: polythiophene, Pb2+, SERS, nanoparticles

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4623 Transcriptome Analysis of Protestia brevitarsis seulensis with Focus On Wing Development and Metamorphosis in Developmental Stages

Authors: Jihye Hwang, Eun Hwa Choi, Su Youn Baek, Bia Park, Gyeongmin Kim, Chorong Shin, Joon Ha Lee, Jae-Sam Hwang, Ui Wook Hwang

Abstract:

White-spotted flower chafers are widely distributed in Asian countries and traditionally used for the treatment of chronic fatigue, blood circulation, and paralysis in the oriental medicine field. The evolution and development of insect wings and metamorphosis remain under-discovered subjects in arthropod evolutionary researches. Gene expression abundance analyses along with developmental stages based on the large-scale RNA-seq data are also still rarely done. Here we report the de novo assembly of a Protestia brevitarsis seulensis transcriptome along four different developmental stages (egg, larva, pupa, and adult) to explore its development and evolution of wings and metamorphosis. The de novo transcriptome assembly consists of 23,551 high-quality transcripts and is approximately 96.7% complete. Out of 8,545 transcripts, 5,183 correspond to the possible orthologs with Drosophila melanogaster. As a result, we could found 265 genes related to wing development and 19 genes related to metamorphosis. The comparison of transcript expression abundance with different developmental stages revealed developmental stage-specific transcripts especially working at the stage of wing development and metamorphosis of P. b. seulensis. This transcriptome quantification along the developmental stages may provide some meaningful clues to elucidate the genetic modulation mechanism of wing development and metamorphosis obtained during the insect evolution.

Keywords: white-spotted flower chafers, transcriptomics, RNA-seq, network biology, wing development, metamorphosis

Procedia PDF Downloads 224
4622 Software Evolution Based Activity Diagrams

Authors: Zine-Eddine Bouras, Abdelouaheb Talai

Abstract:

During the last two decades, the software evolution community has intensively tackled the software merging issue whose main objective is to merge in a consistent way different versions of software in order to obtain a new version. Well-established approaches, mainly based on the dependence analysis techniques, have been used to bring suitable solutions. These approaches concern the source code or software architectures. However, these solutions are more expensive due to the complexity and size. In this paper, we overcome this problem by operating at a high level of abstraction. The objective of this paper is to investigate the software merging at the level of UML activity diagrams, which is a new interesting issue. Its purpose is to merge activity diagrams instead of source code. The proposed approach, based on dependence analysis techniques, is illustrated through an appropriate case study.

Keywords: activity diagram, activity diagram slicing, dependency analysis, software merging

Procedia PDF Downloads 323
4621 Research on the Effect of Coal Ash Slag Structure Evolution on Its Flow Behavior During Co-gasification of Coal and Indirect Coal Liquefaction Residue

Authors: Linmin Zhang

Abstract:

Entrained-flow gasification technology is considered the most promising gasification technology because of its clean and efficient utilization characteristics. The stable fluidity of slag at high temperatures is the key to affecting the long-period operation of the gasifier. The diversity and differences of coal ash-slag systems make it difficult to meet the requirements for stable slagging in entrained-flow gasifiers. Therefore, coal blending or adding fluxes has been used in industry for a long time to improve the flow behavior of coal ash. As a by-product of the indirect coal liquefaction process, indirect coal liquefaction residue (ICLR) is a kind of industrial solid waste that is usually disposed of by stacking or landfilling. However, this disposal method will not only occupy land resources but also cause serious pollution to soil and water bodies by leachate containing toxic and harmful metals. As a carbon-containing matrix, ICLR is not only a kind of waste but also a kind of energy substance. Utilizing existing industrial gasifiers to blend combustion ICLR can not only transform industrial solid waste into fuel but also save coal resources. Moreover, the ICLR usually contains a unique ash chemical composition different from coal, which will affect the slagging performance of the gasifier. Therefore, exploring the effect of the ash addition in ICLR on the coal ash flow behavior can not only improve the slagging performance and gasification efficiency of entrained-flow gasifier by using the unique ash chemical composition of ICLR but also provide some theoretical support for the large-scale consumption of industrial solid waste. Combining molecular dynamics simulation with Raman spectroscopy experiment, the effect of ICLR addition on slag structure and fluidity was explained, and the relationship between the evolution law of slag short/medium range microstructure and macroscopic flow behavior was discussed. The research found that the high silicon and aluminum content in coal ash led to the formation of complex [SiO₄]⁴- tetrahedron and [AlO₄]⁵- tetrahedron structures at high temperature, and the [SiO₄]⁴- tetrahedron and [AlO₄]⁵- tetrahedron were connected by oxygen atoms to form a multi-membered ring structure with high polymerization degree. Due to the action of the multi-membered ring structure, the internal friction in the slag increased, and the viscosity value was higher on the macro-level. As a network-modified ion, Fe2+ could replace Si4+ and Al3+ in the multi-membered ring structure and combine with O2-, which will destroy the bridge oxygen (BO) structure and transform more complex tri cluster oxygen (TO) and bridge oxygen (BO) into simple non-bridge oxygen (NBO) structure. As a result, a large number of multi-membered rings with high polymerization degrees were depolymerized into low-membered rings with low polymerization degrees. The evolution of oxygen types and ring structures in slag reduced the structure complexity and polymerization degree of coal ash slag, resulting in a decrease in the viscosity of coal ash slag.

Keywords: ash slag, coal gasification, fluidity, industrial solid waste, slag structure

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4620 Integrating Reactive Chlorine Species Generation with H2 Evolution in a Multifunctional Photoelectrochemical System for Low Operational Carbon Emissions Saline Sewage Treatment

Authors: Zexiao Zheng, Irene M. C. Lo

Abstract:

Organic pollutants, ammonia, and bacteria are major contaminants in sewage, which may adversely impact ecosystems without proper treatment. Conventional wastewater treatment plants (WWTPs) are operated to remove these contaminants from sewage but suffer from high carbon emissions and are powerless to remove emerging organic pollutants (EOPs). Herein, we have developed a low operational carbon emissions multifunctional photoelectrochemical (PEC) system for saline sewage treatment to simultaneously remove organic compounds, ammonia, and bacteria, coupled with H2 evolution. A reduced BiVO4 (r-BiVO4) with improved PEC properties due to the construction of oxygen vacancies and V4+ species was developed for the multifunctional PEC system. The PEC/r-BiVO4 process could treat saline sewage to meet local WWTPs’ discharge standard in 40 minutes at 2.0 V vs. Ag/AgCl and completely degrade carbamazepine (one of the EOPs), coupled with significant evolution of H2. A remarkable reduction in operational carbon emissions was achieved by the PEC/r-BiVO4 process compared with large-scale WWTPs, attributed to the restrained direct carbon emissions from the generation of greenhouse gases. Mechanistic investigation revealed that the PEC system could activate chloride ions in sewage to generate reactive chlorine species and facilitate •OH production, promoting contaminants removal. The PEC system exhibited operational feasibility at different pH and total suspended solids concentrations and has outstanding reusability and stability, confirming its promising practical potential. The study combined the simultaneous removal of three major contaminants from saline sewage and H2 evolution in a single PEC process, demonstrating a viable approach to supplementing and extending the existing wastewater treatment technologies. The study generated profound insights into the in-situ activation of existing chloride ions in sewage for contaminants removal and offered fundamental theories for applying the PEC system in sewage remediation with low operational carbon emissions. The developed PEC system can fit well with the future needs of wastewater treatment because of the following features: (i) low operational carbon emissions, benefiting the carbon neutrality process; (ii) higher quality of the effluent due to the elimination of EOPs; (iii) chemical-free in the operation of sewage treatment; (iv) easy reuse and recycling without secondary pollution.

Keywords: contaminants removal, H2 evolution, multifunctional PEC system, operational carbon emissions, saline sewage treatment, r-BiVO4 photoanodes

Procedia PDF Downloads 153
4619 Omni: Data Science Platform for Evaluate Performance of a LoRaWAN Network

Authors: Emanuele A. Solagna, Ricardo S, Tozetto, Roberto dos S. Rabello

Abstract:

Nowadays, physical processes are becoming digitized by the evolution of communication, sensing and storage technologies which promote the development of smart cities. The evolution of this technology has generated multiple challenges related to the generation of big data and the active participation of electronic devices in society. Thus, devices can send information that is captured and processed over large areas, but there is no guarantee that all the obtained data amount will be effectively stored and correctly persisted. Because, depending on the technology which is used, there are parameters that has huge influence on the full delivery of information. This article aims to characterize the project, currently under development, of a platform that based on data science will perform a performance and effectiveness evaluation of an industrial network that implements LoRaWAN technology considering its main parameters configuration relating these parameters to the information loss.

Keywords: Internet of Things, LoRa, LoRaWAN, smart cities

Procedia PDF Downloads 142
4618 Molecular Dynamics Simulation Studies of High-Intensity, Nanosecond Pulsed Electric Fields Induced Membrane Electroporation

Authors: Jiahui Song

Abstract:

The use of high-intensity, nanosecond electric pulses has been a recent development in biomedical. High-intensity (∼100 kV/cm), nanosecond duration-pulsed electric fields have been shown to induce cellular electroporation. This will lead to an increase in transmembrane conductivity and diffusive permeability. These effects will also alter the electrical potential across the membrane. The applications include electrically triggered intracellular calcium release, shrinkage of tumors, and temporary blockage of the action potential in nerves. In this research, the dynamics of pore formation with the presence of an externally applied electric field is studied on the basis of molecular dynamics (MD) simulations using the GROMACS package. MD simulations show pore formation occurs for a pulse with the amplitude of 0.5V/nm at 1ns at temperature 316°K. Also increasing temperatures facilitate pore formation. When the temperature is increased to 323°K, pore forms at 0.75ns with the pulse amplitude of 0.5V/nm. For statistical significance, a total of eight MD simulations are carried out with different starting molecular velocities for each simulation. Also, actual experimental observations are compared against MD simulation results.

Keywords: molecular dynamics, high-intensity, nanosecond, electroporation

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4617 Scientific Interpretation of “Fertilizing Winds” Mentioned in Verse 15:22 of Al-Quran

Authors: Md. Mamunur Rashid

Abstract:

Allah (SWT) bestowed us with the Divine blessing, providing the wonderful source of water as stated in verse 15:22 of Al-Quran. Arabic “Ar-Riaaha Lawaaqiha (ٱلرِّيَـٰحَ لَوَٰقِحَ)” of this verse is translated as “fertilizing winds.” The “fertilizing winds” literally, refer the winds of having the roles: to fertilize something similar to the “zygotes” in humans and animals (formation of clouds in the sky in this case); to produce fertilizers for the plants, crops, etc.; and to pollinate the plants. In this paper, these roles of “fertilizing winds” have been validated by presenting the modern knowledge of science in this regard. Existing interpretations are mostly focused on the “formation of clouds in the sky” while few of them mention about the pollination of trees. However, production of fertilizers, in this regard, has not been considered by any translator or interpreter. It has been observed that the winds contain, the necessary components of forming the clouds; the necessary components of producing the fertilizers; and the necessary components to pollinate the plants. The Science of Meteorology gives us the clear understanding of the formation of clouds. Moreover, we know that the lightning bolts breaks the nitrogen molecules of winds and the water molecules of vapor to form fertilizers. Pollination is a common role of winds in plants fertilization. All the scientific phenomena presented here give us the better interpretations of “fertilizing winds.”

Keywords: Al-Quran, fertilizing winds, meteorology, scientific

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4616 Influence of Bacterial Motility on Biofilm Formation

Authors: Li Cheng, Zhang Yilei, Cohen Yehuda

Abstract:

Two motility mechanisms were introduced into iDynoMiCs software, which adopts an individual-based modeling method. Based on the new capabilities, along with the pressure motility developed before, influence of bacterial motility on biofilm formation was studied. Simulation results were evaluated both qualitatively through 3D structure inspections and quantitatively by parameter characterizations. It was showed that twitching motility increased the biofilm surface irregularity probably due to movement of cells towards higher nutrient concentration location whereas free motility, on the other hand, could make biofilms flatter and smoother relatively. Pressure motility showed no significant influence in this study.

Keywords: iDynoMics, biofilm structure, bacterial motility, motility mechanisms

Procedia PDF Downloads 386
4615 The Effect of Different Surface Cleaning Methods on Porosity Formation and Mechanical Property of AA6xxx Aluminum Gas Metal Arc Welds

Authors: Fatemeh Mirakhorli

Abstract:

Porosity is the main issue during welding of aluminum alloys, and surface cleaning has a critical influence to reduce the porosity level by removing the oxidized surface layer before fusion welding. Developing an optimum and economical surface cleaning method has an enormous benefit for aluminum welding industries to reduce costs related to repairing and repeating welds as well as increasing the mechanical properties of the joints. In this study, several mechanical and chemical surface cleaning methods were examined for butt joint welding of 2 mm thick AA6xxx alloys using ER5556 filler metal. The effects of each method on porosity formation and tensile properties are evaluated. It has been found that, compared to the conventional mechanical cleaning method, the use of chemical cleaning leads to an important reduction in porosity level even after a significant delay between cleaning and welding. The effect of the higher porosity level in the fusion zone to reduce the tensile strength of the welds is shown.

Keywords: gas metal arc welding (GMAW), aluminum alloy, surface cleaning, porosity formation, mechanical property

Procedia PDF Downloads 134