Characteristics Of Various Elements Research Articles

An experimental study on the bending fatigue behavior of concrete beams by a proposed machine

Cyclic loading can induce brittle fractures at stress levels below the strength threshold, prompting extensive experimental and numerical investigations into the fatigue characteristics of various elements. This study introduces a purpose-built machine designed to empirically explore the fatigue behavior of concrete beams. The proposed machine employs a rotational beam system with a consistent load applied to the beam’s end. By placing a single point on the rotating beam, cyclic flexural moments are generated, inducing maximum tensile stresses at the support. This machine enables continuous long-term testing, adjustment of load amplitude and loading frequency, and tracking the number of cyclic loads until specimen failure. The stress-number cyclic loading test is performed on diverse samples of both reinforced and unreinforced concrete beams. Furthermore, the study assesses the impact of loading frequency on fatigue behavior. The findings validate existing relationships proposed for the durability limit in terms of tensile strength.

Study on Conservation and Utilization of Traditional Fishing Elements as Cultural Landscape in Japan: Focusing on Conservation and Utilization Policies

In this study, the relationship between various elements of traditional fishing and components of cultural landscape was examined, and the direction of conservation and utilization of traditional fishing was clarified by the characteristics of various elements of traditional fishing through the examples of conservation and utilization of traditional fishing landscape. Firstly, 25 cases of systems, policies and projects for the conservation and utilization of traditional fishing in Japan were extracted from the policies of the national organization in Japan, and the various elements of traditional fishing, related history and culture, efforts and local projects and their results were organized and analyzed, and the multifaceted functions and values of traditional fishing were found. The results show that the traditional fishery has many functions and values. In addition, the characteristics of various elements of traditional fishing and the relevance of and conservation and utilization measures of traditional fishing are discussed.

Stainless steel top-seat angle beam-to-column connection: Full-scale test and analytical modelling

Stainless steel (SS) is increasingly used for structural applications in the construction industry as its beneficial properties outweigh initial material costs when sustainability aspects and the whole life cycle of structures are appropriately accounted for in the structural design. Despite the well-recognised significance of connections in bare metallic construction, experimental research on SS beam-to-column connections, especially full-scale test results, are scarce. This paper presents a full-scale experimental investigation on the semi-rigid behaviour of top-seat bolted connection (also known as ‘flange cleat’ connection) made from austenitic SS. Deformation characteristics of various elements of the connection were carefully investigated and subsequently used to calibrate nonlinear FE models for parametric analysis. Obtained numerical results were used to develop a four-parameter power model that relies on simplified expressions for key input parameters to predict the semi-rigid behaviour of bolted top-seat connections. Results predicted using the proposed model and those obtained using currently available techniques based on carbon steel behaviour were compared. Outcomes of the current research highlighted the significance of appropriate inclusion of stain hardening offered by austenitic grade to capture the semi-rigid response of such connections.

Simulation of stock market investor behavior based on bayesian learning and complex network

The increasing complexity of the financial system has increased the uncertainty of the market, which has led to the complexity of the evolution of limited rational investor behavior decisions. Moreover, it also has a negative effect on the market and affects the development of the real economy and social stability. In view of the interconnected characteristics of various elements presented in financial complexity, based on complex network theory, Bayesian learning theory and social learning theory, this study systematically describes the behavioral decision-making mechanism of individual investors and institutional investors from the perspective of network learning. In addition, this study builds an evolutionary model of investor behavior based on Bayesian learning strategies. According to the results of the horizontal and vertical bidirectional studies simulated by experiments, we can see that the method proposed in this study has a certain effect on the evaluation and decision support of stock market investment.

Proposal and Explanation of a New Periodic Table of the Chemical Elements

In the original periodic table of chemical elements, inert gas elements are arranged to the end of each cycle, and more phenomena can be explained by valency based on the combination of inorganic substances. In this paper, a new periodic table of elements is formulated based on retaining the original number of nuclear protons, neutrons and extra nuclear electrons, referring to the square correlation between the direct ratio of sphere area and radius, and some properties of elements. In the new table, it is considered that electrons fill spheres with radius of 1,2,3,4in turn, for example, one electron filling in the first cycle corresponds to one element of hydrogen (H); the radius of the second cycle is 2, sphere area is four times that of the first cycle, then four electrons can be filled, which correspond to four elements of He, Li, Be and B; the number element of the third cycle is square of 3, 9, and so on. The new table can better explain the distribution of certain elements, which is conducive to understanding the characteristics of various elements from another angle and expanding the insight into the micro world.

Thermal behaviour of ESP ash from municipal solid waste incinerators

Stricter environmental regulations demand safer treatment and disposal of incinerator fly ashes. So far no sound technology or a process is available for a sustainable and ecological treatment of the waste incineration ashes, and only partial treatment is practised for temporary and short-term solutions. New processes and technology need to be developed for comprehensive utilization and detoxification of the municipal solid waste (MSW) incinerator residues. To explore the efficiency of thermal stabilisation and controlled vitrification, the thermal behaviour of electrostatic precipitator (ESP) ash was investigated under controlled conditions. The reaction stages are identified with the initial moisture removal, volatilisation, melting and slag formation. At the temperature higher than 1100 °C, the ESP ashes have a quicker weight loss, and the total weight loss reaches up to 52%, higher than the boiler ash. At 1400 °C a salt layer and a homogeneous glassy slag were formed. The effect of thermal treatment on the leaching characteristics of various elements in the ESP ash was evaluated with the availability-leaching test. The leaching values of the vitrified slag are significantly lowered than that of the original ash.

Thermal treatment and vitrification of boiler ash from a municipal solid waste incinerator

Boiler ash generated from municipal solid waste (MSW) incinerators is usually classified as hazardous materials and requires special disposal. In the present study, the boiler ash was characterized for the chemical compositions, morphology and microstructure. The thermal chemical behavior during ash heating was investigated with thermal balance. Vitrification of the ash was conducted at a temperature of 1400 °C in order to generate a stable silicate slag, and the formed slag was examined with chemical and mineralogical analyses. The effect of vitrification on the leaching characteristics of various elements in the ash was evaluated with acid leaching. The study shows that the boiler ash as a heterogeneous fine powder contains mainly silicate, carbonate, sulfates, chlorides, and residues of organic materials and heavy metal compounds. At elevated temperatures, the boiler ash goes through the initial moisture removal, volatilization, decomposition, sintering, melting, and slag formation. At 1400 °C a thin layer of salt melt and a homogeneous glassy slag was formed. The experimental results indicate that leaching values of the vitrified slag are significantly reduced compared to the original boiler ash, and the vitrification could be an interesting alternative for a safer disposal of the boiler ash. Ash compacting, e.g., pelletizing can reduce volatilization and weight loss by about 50%, and would be a good option for the feed preparation before vitrification.

The role of mass spectrometry to study the Oklo–Bangombé natural reactors

The discovery of the existence of chain reactions at the Oklo natural reactors in Gabon, Central Africa in 1972 was a triumph for the accuracy of mass spectrometric measurements, in that a 0.5% anomaly in the (235)U/(238)U ratio of certain U ore samples indicated a depletion in (235)U. Mass spectrometric techniques thereafter played a dominant role in determining the nuclear parameters of the reactor zones themselves, and in deciphering the geochemical characteristics of various elements in the U-rich ore and in the surrounding rock strata. The variations in the isotopic composition of a large number of elements, caused by a combination of nuclear fission, neutron capture and radioactive decay, provide a powerful tool for investigating this unique geological environment. Mass spectrometry can be used to measure the present-day elemental and isotopic abundances of numerous elements, so as to decipher the past history of the reactors and examine the retentivity/mobility of these elements. Many of the fission products have a radioactive decay history that have been used to date the age and duration of the reactor zones, and to provide insight into their nuclear and geochemical behavior as a function of time. The Oklo fission reactors and their near neighbor at Bangombé, some 30 km to the south-east of Oklo, are unique in that not only did they become critical some 2 x 10(9) years ago, but also the deposits have been preserved over this period of geological time. The long-term geochemical behavior of actinides and fission products have been extensively studied by a variety of mass spectrometric techniques over the past 30 years to provide us with significant information on the mobility/retentivity of this material in a natural geological repository. The Oklo-Bangombé natural reactors are therefore geological analogs that can be evaluated in terms of possible radioactive waste containment sites. As more reactor zones were discovered, it was realized that they could be classified into two groups according to their burial depth in the Oklo mine-site. Reactor Zones 10, 13, and 16 were buried more deeply, and were therefore less weathered than the other zones. The less-weathered zones are of great importance in mobility/retentivity studies and therefore to the question of radioactive waste containment. Isotopic studies of these natural reactors are also of value in physics to examine possible variations in fundamental constants over the past 2 billion years.

Element suitability for circularly polarised phase agile reflectarray applications

The electrical characteristics of various elements that can be used as spatial phase shifters in circularly polarised (CP) reflectarrays are contrasted. The elements investigated are; a single rotating dipole at 10.3 GHz; a multiple dipole at 18.2 GHz; a rotating stub at 2.8 GHz; and a periphery point short-circuited circular patch at 3.0 GHz. For each element type, results are presented for the reflection phase, polarisation purity and reflection loss. Where appropriate, experiments are performed using the waveguide simulator technique to validate the numerical EM simulation.

Earthquake response of inelastic structures

The most commonly used method in the seismic analysis of structures is the response spectrum method. For seismic re-evaluation of existing facilities elastic response spectrum method cannot be used directly as large deformation above yield may be observed under Safe Shutdown Earthquake (SSE). The plastic deformation, i.e. hysteretic characteristics of various elements of the structure cause dissipation of energy. Hence the values of damping given by the code, which does not account hysteretic energy dissipation cannot be directly used. In this paper, appropriate damping values are evaluated for 5-storey, 10-storey and 15-storey shear beam structures, which deform beyond their yield limit. Linear elastic analysis is performed for the same structures using these damping values and the storey forces are compared with those obtained using inelastic time history analysis. A damping model, which relates ductility of the structure and damping, is developed. Using this damping model, a practical structure is analysed and results are compared with inelastic time history analysis and the comparison is found to be good.

Interdiffusion studies in titanium–304 stainless steel system

The interdiffusion characteristics of various elements in Ti–304SS system have been investigated in the temperature range between 976 and 1123 K by employing metallographic and electron probe microanalysis techniques. The diffusion zone of the couple has been found to be of solid solution type and the layer growth can be presented by two linear lines with change of slope lying in the region of Curie temperatures of the alloys. The layer growth kinetics (in the temperature range of 1023–1123 K) can be expressed by the following Arrhenius relationship: X=2.3×10 5 exp (−73.96 kJ/mol/RT)t 1/2, m. The concentration and temperature dependence of effective interdiffusion coefficients are evaluated and the diffusion parameters are established. It is observed that the minimum activation energy value for interdiffusion of Ti (78.05 kJ/mol at 60 at.% Ti) and Fe (74.05 kJ/mol at 20 at.% Fe) and the activation energy for layer growth (73.96 kJ/mol) are in good agreement, suggesting that growth kinetics is controlled by the migration of the plane having the composition of ∼60% Ti, ∼20% Fe, ∼10% Ni and ∼10% Cr.