PURKH (E-Journals)
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Impact of pressure energy on the space-time - thermodynamic aspect
No full textBased on the definition of pressure relating to the space and the first law of thermodynamics has been derived the equation that illustrates the relationship between the values of pressure and volume of space-time - from the subatomic volume values 10-43 m3Js to the maximum values 10+38 m3Js (or higher). The presented model seems to be in compatibility both with the theories describing the evolution of space-time and with the experimental data. The model shows that the volume of space-time is still increasing and will continue to increase, which is consistent with the observations. It seems that the presented model can also predict what happens beyond the observable Universe. This model seems to confirm the hypothesis of eternal inflation as well as the infinity of space-time. This model may help explain the nature of dark energy, responsible for accelerating the expansion of space-time. Generally, we would show how the pressure energy impact on the whole space-time. We think that the model of the relationship between the energy of pressure and space-time volume presented by us may be of interest to researchers dealing with dark energy problems, as well as students and others
Design and Construction of Multi-input Audio Mixer: Design and Construction of Multi-input Audio Mixer
No full textDue to exorbitant prices, difficulty in operation, and high cost of maintenance of existing audio console, a simple, efficient, and cost-effective multi-input audio mixer has been designed and constructed. A simple design achieved this with three sections: power supply, pre-amplifier, and power amplifier sections. The audio console was designed with a high-grade operational amplifier with very low distortions. The power supply section was constructed by connecting the secondary terminals of 12 V transformers to a bridge rectifier for optimum power supply to the system. The pre-amplifier section was constructed using a BC547 NPN transistor. The power amplifier was constructed using the LM386 IC for high-quality output. The design carefully combined (audition/program) units to achieve good mixing and balancing. The design was done to achieve a maximum gain with refined audio output.
Research Progress of Common Organic Guanidine Antibacterial Agents
No full textAim: The aim of this study is to investigate the antimicrobial properties of organic guanidine because of their strong alkalinity, high stability, low toxicity and good biological activity. Methods: By referring to the relevant domestic and foreign literature, the physical and chemical properties, uses, preparation methods, germicidal efficacy and germicidal mechanism of guanidine compounds commonly used in alkyl guanidine, aryl guanidine, and polymerized guanidine with antibacterial properties were briefly analyzed and summarized. Result: It has been found that dodecylguanidine acetate in long-chain alkyl monoguanidine, iminoctadine in long-chain alkyl biguanide, chlorhexidine in aryl guanidine, polyhexamethylene biguanide hydrochloride(PHMB)and polyhexamethylene guanidine hydrochloride(PHMG) in polymerized guanidine all had killing or inhibiting effects on bacteria, fungi and viruses. Conclusion: Guanidine compounds with broad-spectrum and high-efficiency bactericidal effect can not only be used as antibacterial agents alone, but also can be introduced into polymers to prepare materials with antibacterial properties, and the development prospect of organic guanidine antibacterial coatings is prospected
Research Collaboration in Mathematical Applications and Innovations to Solve Community Challenges: A Position Paper
No full textThe U.N. General Assembly has declared, through its 2030 Sustainable Development Goals, to transform the world. This can be achieved through enhancing scientific research, among other things. Following suit, Zimbabwe strives to attain a middle economy status by the year 2030. In this regard, Zimbabwean researchers and academia will be required to produce quality goods and services that contribute to the viability and sustainability of the communities and the country at large. Regarding academia, the basis for the promotion of university lecturers in Zimbabwe is now the Philosophy of Education 5.0 system, which is centered on five pillars, which include teaching, research, community service, innovations, and industrialization. To achieve this philosophy, this position paper which focuses on STEM subjects but is more biased towards mathematical thinking and learning argues for research collaboration and high impact research, especially research that helps to solve community challenges. It also challenges the readers and researchers to offer practical solutions to some chosen problems in the STEM disciplines and concludes by suggesting strategies of forming research groups or ‘collaborations,’ especially during conferences or workshops, and recommends that institutions should adequately fund high impact research. Points and suggestions raised in this paper can apply to other countries too, especially those with developing economies
Effect of Moral Values on National Security: The Role of Citizenship Education
No full textCitizenship education has been acknowledged by means of scholars and educationalists as an indispensable phase of countrywide monetary empowerment and development techniques in industrialized and developed nations globally, due to its influence on ethical values and national security. However, the harness of youth's potentials through citizenship education has not accelerated sustainability in Nigeria. The study, therefore, seeks to examine the influence of citizenship education on moral values and national protection with precise reference to Colleges of Education in South West of Nigeria. A survey research method was adopted to pattern the opinion of 1,448 college students of the colleges of education in the six states. The structured questionnaires designed for the study was used to collect data, while analysis was performed via mean, standard deviation, and linear regression. The study establishes that citizenship education is a riding force of moral price and national security. It was recommended that citizenship education be delivered and made a core course for all students in tertiary institutions in Nigeria
Investigation of the Effects of Varying Copper Concentrations on the Mechanical Properties of Aluminium
Get PDFThe effects of varying Cu concentrations on the mechanical properties of pure Al has been investigated. Seven samples of Al-Cu alloy systems with copper concentrations 0.0%,2.5%,5.0%,7.5%,10.0%,12.5% and 15.0% by wt% labelled A, B,C,D,E, F, and G respectively were fabricated and subjected to hardness, tensile strength, yield strength, and ductility tests, optical microstructural examinations were carried out on each of the samples. Results showed that the tensile strength and hardness of the Al alloy samples increased with increase in copper concentration for all the samples, while the yield strength increased progressively from samples A to E and remained constant for samples E to G. However, the ductility of the samples decreased with increase in copper concentrations. The microstructural examinations of the alloy samples revealed a decrease in the grain boundaries of Al-Cu alloy samples with an increase in copper concentrations. This resulted to an increase in the hardness, tensile strength, yield strength, and decrease in ductility as copper concentration increased. It can be concluded, that the mechanical properties of Al can be altered with a systematic increase in copper concentration within the experimented samples
A Study of Written Grammatical Errors of the Indian Subcontinent Learners: A Systematic Revie
Get PDFThis paper investigates A Study of Written Grammatical Errors of the Indian Subcontinent Learners in English settings from 2008 to 2018. Grammar is one of the most important subjects in English language that has been discussed among great scholars, teachers, syllabus designers in the history of English language teaching. Grammar plays vital role in increasing and decreasing the knowledge of English language learners is not only in non- English –speaking countries settings but also in English –speaking countries. Therefore, English grammar is still a big problem for English native students in their classrooms. Error analysis is used as one of the language learning strategies in which focuses on language competence of language learners in the target language. Thus, the error analysis approach was coined by Corder in 1967. In this study, researchers have tried to study the written grammatical errors committed by Indian Subcontinent students in English language from 2008 to 2018 and suggested remedial measures to improve the written grammatical errors from the research works. In addition, for various historical reasons, English has, for more than two hundred years, been growing in the Indian socio-cultural setting. We hope that this paper examines a systematic study of learners' errors in this area. Finally, the researcher of this paper examined the previous research works on grammatical errors in the English language, which were published from 2008 to 2018 in the Indian Subcontinent. In addition, of 150 research papers were examined in the paper, 36 of the research papers were relevant
On special FCn-cell modules
Get PDFIn this paper, we study a specied family of Fuss-Catalan algebra cell modules. We define the set of the basis diagrams and we give the general form for the Gram matrix related to this family. In addition, we state when these modules are irreducible by finding the determinant of the Gram matrices. Finally, we define a homomorphism between certain cell modules
Formation of Alkaline Earth and Transition Metal Complexes with Efavirenz Drug in Ethanol-Water Media
Get PDFThe stability constant of Efavirenz drug with alkaline earth metal ions Mg(II), Ca(II) and transition metal ions Fe(III), Cu(II) were investigate using pH metric titration technique in 20%(v/v) ethanol-water mixture at 27 °C temperature and at an ionic strength of 0.1M NaClO4.{Metal to ligand ratio = 1:5 & 1:1}The method of Calvin and Bjerrum as adopted by Irving and Rossotti has been employed to determine proton ligand (pKa) and metal-ligand stability constants (log K) values. It is observed that alkaline earth metal & transition metal ion forms 1:1 and 1:2 complexes. The order of stability constants for these metal complexes was as: Fe3+ > Cu2+ > Mg2+ > Ca2+
Simulation-based Comparison between Reactive and Proactive Routing Protocols
No full textMobile ad hoc networks (MANETs) are widely used in recent years due to its ease of installation and configuration, and its success in a wide range of applications, such as military operations, health monitoring, and detection of natural disasters. A MANET consists of a group of mobile nodes that are formed spontaneously, i.e., no specific topology is followed. The main objective of this paper is to compare the performance of MANETs when either a reactive or proactive routing protocol is employed as its routing method. The Ad hoc on-demand distance vector (AODV), and the destination-sequenced distance-vector (DSDV) routing protocols were chosen for the comparison as they are the most commonly used reactive and proactive routing protocols. The comparison was based on a simulation method in which the network simulator (NS-2.35) and network scenario generator (NSG2.1) were used to perform the comparison process. Network metrics, such as packet delivery ratio (PDR), throughput, routing overhead, and packet loss, were involved in the comparison process as referenced values. Based on the results obtained, a MANET that employs an AODV protocol would have a better performance as it exhibits a higher packet delivery ratio, higher throughput, lower routing overhead, and lower packet loss.