58 research outputs found

    Evaporation Phenomenon Inside a Solar Still: From Water Surface to Humid Air

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    This demonstration illustrates how the water cycle helps to purify water. Students are introduced to the key terms, which are evaporation and condensation. They discover that evaporation is defined as the process through which a liquid becomes a vapor, while condensation is simply the reverse. Students also learn that in the case of water, the main mechanisms for evaporation and condensation are heating and cooling, respectively. Educational levels: Intermediate elementary, Primary elementary

    Matter collineations of Spacetime Homogeneous G\"odel-type Metrics

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    The spacetime homogeneous G\"odel-type spacetimes which have four classes of metrics are studied according to their matter collineations. The obtained results are compared with Killing vectors and Ricci collineations. It is found that these spacetimes have infinite number of matter collineations in degenerate case, i.e. det(Tab)=0(T_{ab}) = 0, and do not admit proper matter collineations in non-degenerate case, i.e. det(Tab)≠0(T_{ab}) \ne 0. The degenerate case has the new constraints on the parameters mm and ww which characterize the causality features of the G\"odel-type spacetimes.Comment: 12 pages, LaTex, no figures, Class. Quantum.Grav.20 (2003) 216

    Volatile Constituents of Leaves of Trifolium alexandrinum

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    This study presents the volatile constituents from leaves of Trifolium alexandrinum from Pakistan. The dried leaves were subjected to hydrodistillation for extraction and extracted volatile oil was subsequently characterized by gas chromatography-mass spectrometry technique. A total of 22 compounds were identified where the most dominant constituents were: phytol (46.00%), palmitic acid (9.26%), phytol acetate (6.44%), and linolenic acid (3.47%). Most of these are well-known constituents to exhibit antibacterial, antioxidant, antitumor, and anti-inflammatory activities

    Numerical Investigation of Rising Vapour Bubble in Convective Boiling Using an Advanced 3D Hybrid Numerical Method

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    This chapter introduces an advanced and new type of Three-Dimensional (3D) numerical method called the InterSection Marker (ISM) method. The ISM method - a hybrid Lagrangian–Eulerian 3D front-tracking algorithm specifically crafted for multi-phase flow simulation. The method was used to simulate rising vapour bubble behaviour in Convective boiling conditions. Two applications: bubble growth and bubble condensation due to the convective action, were investigated. Numerically obtained bubble properties, such as size, shape and velocity, are compared well against the past works, and the ISM method proved to be an efficient numerical tool for the interface tracking of multi-phase flow CFD simulations involving heat and mass transfer

    The role of information and communication technology in encountering environmental degradation: Proposing an SDG framework for the BRICS countries

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    Sustainability through information and communication technologies is a complex matter, raising interesting debate among researchers. Pursuing the same, this research investigates the impact of information and communication technologies, economic growth, and financial development on carbon dioxide emissions by simultaneously testing the Environmental Kuznets curve (EKC) hypothesis in BRICS countries. In doing so, this study employs Methods of Moments - Quantile Regression, which confirms that the effects of the explanatory variables vary across different quantiles of carbon dioxide emissions. The overall results indicate that economic growth and financial development contribute to carbon dioxide emissions across all quantiles, while information and communication technologies significantly mitigate the level of carbon dioxide emissions only at lower emissions quantiles. Moreover, the results confirm the presence of the EKC hypothesis. Interestingly, the effect of economic growth and information and communication technologies on carbon dioxide emissions is lowest in magnitude at lower quantiles and highest at higher quantiles of carbon dioxide emissions. The empirical findings of DH panel heterogenous causality test confirm bidirectional causality between the model parameters, indicating that any policy intervention concerning explanatory variables significantly causes carbon dioxide emissions and vice versa. The results set out the foundation for policymakers to devise a policy framework to attain the objectives of Sustainable Development Goals (SDGs)

    Fundamentals and applications of acrylamide based microgels and their hybrids: a review

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    Acrylamide based microgels have gained a lot of attention in the last three decades due to their potential applications in various fields based on their responsive behavior and chemical stability. In this article, the synthesis, properties, and applications of poly(N-isopropylacrylamide-co-acrylamide) [P(NIPAM-Am)] microgels and P(NIPAM-Am) microgels having an additional ionic moiety in their network [P(NIPAM-Am-IM)] are reviewed. These microgels may swell/deswell reversibly with slight changes in environmental conditions such as change in temperature/pH/ionic strength etc. of the medium. This responsive behavior makes the microgels a potential candidate for use in the field of nanotechnology, drug delivery, sensing and catalysis. A critical overview of the recent research progress in this area along with future perspectives is presented. The discussion is concluded with suggested possible future studies for further development in this area

    The nexus between urbanization, renewable energy consumption, financial development, and CO2 emissions: evidence from selected Asian countries

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    In terms of attaining the objectives of Sustainable Development Goals (SDGs), the Asian economies are considered as laggards, and one of the major problems faced by these economies is the issue of environmental degradation. For addressing this pertaining issue, a policy-level reorientation might be necessary. In this view, this study aims to explore the impact of urbanization, renewable energy consumption, financial development, agriculture, and economic growth on CO2 emissions in 15 Asian economies over 1990-2014. The empirical evidence demonstrates that urbanization, financial development, and economic growth increase CO2 emissions, renewable energy consumption reduces CO2 emissions, and the impact of agriculture is insignificant. Impulse response function and variance decomposition techniques are used to test the causality among the variables. Based on the study outcomes, a comprehensive SDG-oriented policy framework has been recommended, so that these economies can make progression towards attaining the objectives of SDG 13 and SDG 7. This study contributed to the literature by recommending this SDG-oriented policy framework, which encapsulates economic growth and its drivers

    Nyctanthes arbor-tristis

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    Nyctanthes arbor-tristis (NAT) is commonly used traditionally for the treatment of rheumatism and inflammatory diseases. Current study evaluates the antiarthritic potential of NAT using Freund’s adjuvant-induced arthritic rat model. Treatments with methanolic, ethyl acetate, and n-hexane extracts were continued for consecutive 20 days. Macroscopic arthritic scoring and water displacement plethysmometry were used to evaluate arthritic development. Hematological and biochemical parameters were investigated and ankle joints were processed for histopathological evaluation. Qualitative phytochemical analysis and GC-MS analysis were conducted for identification of constituents. NAT extracts suppressed arthritic scoring, paw edema, infiltration of inflammatory cells, pannus formation, and bone erosion. The plant extracts ameliorated total leukocytes and platelet counts and nearly normalized red blood cells (RBC) counts and hemoglobin (Hb) content. The extracts were found safe in terms of hepatotoxicity and nephrotoxicity as determined by aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, and urea levels. Comparative analysis showed that ethyl acetate extract produced the highest inhibition of paw edema. The major constituents found in ethyl acetate extract can be classified into three major classes, that is, terpenes, terpenoids, fatty acids, and iridoid glycosides. Current study showed that Nyctanthes arbor-tristis ameliorated experimental rheumatoid arthritis and ethyl acetate extract possessed the highest inhibitory activity
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