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One Pot Hydrothermal Synthesis and Application of Bright-yellow-emissive Carbon Quantum Dots in Hg2+ Detection
Carbon quantum dots (CQD) have drawn great interest worldwide for their extensive application as sensors due to their extraordinary physical and chemical characteristics, good biocompatibility, and high fluorescence in nature. Here, we demonstrate a technique for detecting mercury (Hg2+) ion using a fluorescent CQD probe. Ecology is concerned about the accumulation of heavy metal ions in water samples due to their harmful effects on human health. Sensitive identification and removal of metal ions from water samples are required to reduce heavy metals risk. To find out Mercury in the water sample, carbon quantum dots were used and synthesized by 5-dimethyl amino methyl furfuryl alcohol and o-phenylene diamine through the hydrothermal technique. The synthesized CQD shows yellow emission when exposed to UV irradiation. Mercury ion was used to quench carbon quantum dots, and it was found that the detection limit was 5.2 nM with a linear range of 15100 M. The synthesized carbon quantum dots were demonstrated to efficiently detect Mercury ions in real water samples. 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
On-off fluorescence detection of exposed phosgene via pyrazine ring formation on a triphenyl amine backbone supplemented with a theoretical approach and practical environmental applications
Using 4-(diphenylamino)benzaldehyde as the fluorophore and 2,3-diaminomaleonitrile, a fluorescent probe known as 2-amino-3-(((E)-4-(diphenylamino)benzylidene)amino)-maleonitrile (ADM) has been developed for the selective detection of phosgene through a unique cyclization pathway producing a substituted pyrazine derivative attached to a triphenyl amine backbone. This reaction led to a notable reduction in the emission intensity of ADM at 565 nm. This is the first study that reports ADM as a sensory material for the selective detection of phosgene, achieved by forming a new heterocyclic pyrazine structure. With a quick response time of only 80 seconds, the detection limit of the probe ADM towards phosgene has been calculated as 4.23 ?M. Several spectroscopic methods, including UV-vis, emission spectroscopy, mass spectrometry, and computational investigations are used to study the sensing behavior. In practical applications, the sensor ADM can be used for soil analysis, the dipstick method, and the detection of phosgene from chlorinated hydrocarbon sources such as dichloromethane, chloroform and household solvents like paint remover. 2024 The Royal Society of Chemistry. -
On-board intelligent energy management system for gridable electric vehicles and a method thereof /
Patent Number: 202141037003, Applicant: Parag Jose Chacko.
The idea proposed is an Intelligent Energy Management System (1EMS) which will be on board a Gridable Electric Vehicle (GEV) for enabling Grid Integration to facilitate Grid to Vehicle (G2V), Vehicle to Grid (G2V) and Vehicle to Vehicle (V2V) active power flow. Gridable Electric Vehicles are vehicles coming under the category of Plug-in Hybrid Electric Vehicles (PHEV) and Battery operated Electric Vehicles (BEV). The interest towards alternate transportation is increasing due to the increasing fuel prices and the increased air pollution. -
On-board intelligent energy management system for gridable electric vehicles and a method thereof /
Patent Number: 202141037003, Applicant: Parag Jose Chacko.The idea proposed is an Intelligent Energy Management System (1EMS) which will be on board a Gridable Electric Vehicle (GEV) for enabling Grid Integration to facilitate Grid to Vehicle (G2V), Vehicle to Grid (G2V) and Vehicle to Vehicle (V2V) active power flow. Gridable Electric Vehicles are vehicles coming under the category of Plug-in Hybrid Electric Vehicles (PHEV) and Battery operated Electric Vehicles (BEV). The interest towards alternate transportation is increasing due to the increasing fuel prices and the increased air pollution. -
On-board intelligent energy management system for gridable electric vehicles and a method thereof /
Patent Number: 202141037003, Applicant: Parag Jose Chacko.
The idea proposed is an Intelligent Energy Management System (1EMS) which will be on board a Gridable Electric Vehicle (GEV) for enabling Grid Integration to facilitate Grid to Vehicle (G2V), Vehicle to Grid (G2V) and Vehicle to Vehicle (V2V) active power flow. Gridable Electric Vehicles are vehicles coming under the category of Plug-in Hybrid Electric Vehicles (PHEV) and Battery operated Electric Vehicles (BEV). The interest towards alternate transportation is increasing due to the increasing fuel prices and the increased air pollution. -
On-board Converter for Electric Vehicle Charging using LCLC Resonant Topology
Due to their high efficiency, high power density, and soft switching characteristics, LLC-based AC-DC resonant converters are a great choice for EV chargers. Adding a capacitor across the magnetizing inductance of the LLC resonant architecture (LCLC configuration) enhances efficiency and reduces the need for a larger series inductor. The output DC voltage of the converter is generally regulated using switching frequency control. However, the power factor of the converter varies significantly with the switching frequency. As a result, any fluctuations in load may cause the converter to operate at a lower power factor. This paper proposes a single-stage topology based on the LCLC resonant structure. Zero voltage switching (ZVS) of the IGBTs used in the converter is ensured by the LCLC resonant configuration. Converter have a power factor correction (PFC) stage on the front of the converter to achieve natural power factor correction. Since the PFC stage and the resonant stage are controlled by the same switches, the converter is smaller and less costly. Simulations in MATLAB/Simulink are used to validate the topology. 2023 IEEE. -
On Πk – connectivity of some product graphs
Vol. 21, No.2, 70 - 79 ISSN 13105132 -
On Two-Dimensional Approximate Pattern Matching Using Fuzzy Automata
Pattern matching has been extensively studied in the last few decades, owing to its great contribution in various fields such as search engines, computational biology, etc. Several real-life situations require patterns that allow ambiguity in specified positions. In this paper, one-dimensional and two-dimensional approximate pattern matching models have been constructed using fuzzy automata. The similarity function used in fuzzy automata enables the occurrence of all exact and similar one-dimensional and two-dimensional patterns. This kind of searching approximate patterns is not possible with regular search models. The time complexity of the proposed algorithm has also been analyzed. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024. -
ON TRANSFORMED GRAPHS
The network systems and graphical analysis through the study of structural characteristics is a vast field of growing importance in research. Topological indices have a significant and crucial role in the study of structureproperty relationships. In this paper, we examine constructional transformed networks constructed by unique vertex-edge incidence and mutual adjacency associations. Expressions for the first and second hyper Zagreb indices and co-indices of these transformed networks and their complements are obtained. 2023, RAMANUJAN SOCIETY OF MATHEMATICS AND MATHEMATICAL SCIENCES. All rights reserved. -
On thermal performance of spine fin in magnetized hybrid fluid rooted with Cu and MoS4 nanoparticles
This study examines the thermal performance of diverse profiles of spine fins with variable thermal conductivity. A hybrid nanofluid comprising Cu, and MoS4 with water as the base fluid, is modeled mathematically. Both the cylindrical and concave parabolic profiles are taken into account. The comparative outcomes are inferred from numerical and semi-analytical methods. The non-dimensional temperature profiles are analyzed graphically while considering the fin tip to be insulated, and the effects of various thermal parameters are also investigated. We have observed that the heat transfer rate shows an opposite trend toward convective-conduction and porosity parameter. The study also revealed that the concave parabolic profile emits more heat in comparison with the cylindrical profile. 2024 Author(s). -
On the zero forcing number of graphs and their splitting graphs
In [10], the notion of the splitting graph of a graph was introduced. In this paper we compute the zero forcing number of the splitting graph of a graph and also obtain some bounds besides finding the exact value of this parameter. We prove for any connected graph ? of order n ? 2, Z[S(?)] ? 2Z(?) and also obtain many classes of graph in which Z[S(?)] = 2Z(?). Further, we show some classes of graphs in which Z[S(?)] < 2Z(?). Journal Algebra and Discrete Mathematics. -
On the Way to Oneself : An Existential Study of the Select Plays of Sreeja K V and Sajitha Madathil
The perennial inquiries into human identity and the purpose of existence persist as enduring mysteries, often evoking a sense of introspection and existential angst. Amidst the quest for elucidation, individuals frequently find themselves entangled in the web of maya (appearance), wherein perceptions of reality become distorted, leading to emotional responses including jealousy, greed, guilt, and disappointment. However, amidst this labyrinth of existence, philosophical frameworks such as Existentialism and Advaita Vedanta offer invaluable lenses through which to perceive and engage with these existential inquiries. Existentialism prompts individuals to confront the subjective nature of their existence and assert autonomy in defining their identities and purpose. In contrast, Advaita Vedanta seeks to transcend the illusory veil of ego and perceive the ultimate reality of the Self (atman) as indistinguishable from the eternal consciousness (Brahman). Through the exploration of these philosophical paradigms, one can embark on a journey of Self- discovery, ultimately unveiling insights into the timeless questions of human existence. It is possible to identify this kind of crisis in the lives of the characters in the selected plays of Sreeja K V and Sajitha Madathil. Therefore, this thesis examines the selected plays of twenty-first-century Malayalam playwrights Sreeja K V and Sajitha Madathil through the lens of Simone de Beauvoir's existentialism and the pramana of Advaita Vedanta. It aims to explore the concept of the Self and how certain circumstances and experiences contribute to its realisation. By analysing the protagonists of these plays, the thesis seeks to uncover the notion that the Self is not merely a product of causality but rather the observer and creator of existence itself. This investigation raises further questions regarding the manifestation of the Self in one's life and the potential for misconceptions about its nature. The plays provide insights into the interaction between worldly illusions and the true essence of the Self, prompting consideration of how individuals often conflate these realms and succumb to materialistic temptations. Additionally, the thesis explores whether negative experiences are transient and whether individuals ultimately learn to overcome them. The selected plays open up the scope to understand the interplay of illusions of the world and the Self. This exploration leads to further questions like how does the Self appear in ones life? Is the Self mistaken? How often do people superimpose these two together and fall prey to the materialistic aspects? Is it true that the negative experiences are momentary, and often, one learns to survive from those experiences? Through the application of analytical frameworks of Existentialism and Advaita Vedanta into the select plays, this research endeavours to provide insights into these inquiries. -
On the Temporal Causal Relationship Between Macroeconomic Variables: Empirical Evidence From India
The present study examines the dynamic interactions among macroeconomic variables such as real output, prices, money supply, interest rate (IR), and exchange rate (EXR) in India during the pre-economic crisis and economic crisis periods, using the autoregressive distributed lag (ARDL) bounds test for cointegration, Johansen and Juselius multivariate cointegration test, Granger causality/Block exogeneity Wald test based on Vector Error Correction Model, variance decomposition analysis and impulse response functions. The empirical results reveal a stronger long-run bilateral relationship between real output, price level, IR, and EXR during the pre-crisis sample period. Moreover, the empirical results confirm a unidirectional short-run causality running from price level to EXR, IR to price level, and real output to money supply during the pre-crisis period. Also, it is evident from the test results that there exist short-run bidirectional relationships running between real output and EXR, price level and IR, and IR and EXR in the pre-crisis era, respectively. Most importantly, long-run bidirectional causality is found between real output, EXR, and IR during the economic crisis period. And the study results indicate short-run bidirectional causality between money supply and EXR, IR and price level, and IR and output in India during the crisis era. Also, a short-run unidirectional causality runs from prices to real output in the crisis period. The Author(s) 2014. -
On the secure vertex cover pebbling number
A new graph invariant called the secure vertex cover pebbling number, which is a combination of two graph invariants, namely, secure vertex cover and cover pebbling number, is introduced in this paper. The secure vertex cover pebbling number of a graph, G, is the minimum number m so that every distribution of m pebbles can reach some secure vertex cover of G by a sequence of pebbling moves. In this paper, the complexity of the secure vertex cover problem and secure vertex cover pebbling problem are discussed. Also, we obtain some basic results and the secure vertex cover pebbling number for complete r-partite graphs, paths, Friendship graphs, and wheel graphs. 2023 World Scientific Publishing Co. Pte Ltd. All rights reserved. -
On the rainbow neighbourhood number of set-graphs
In this paper, we present results for the rainbow neighbourhood numbers of set-graphs. It is also shown that set-graphs are perfect graphs. The intuitive colouring dilemma in respect of the rainbow neighbourhood convention is clarified as well. Finally, the new notion of the maximax independence, maximum proper colouring of a graph and a new graph parameter called the i-max number of G are introduced as a new research direction. 2020 the author(s). -
On the rainbow neighbourhood number of Mycielski type graphs
A rainbow neighbourhood of a graph G is the closed neighbourhood N[v] of a vertex v ? V (G) which contains at least one colored vertex of each color in the chromatic coloring C of G. Let G be a graph with a chromatic coloring C defined on it. The number of vertices in G yielding rainbow neighbourhoods is called the rainbow neighbourhood number of the graph G, denoted by rX(G). In this paper, we discuss the rainbow neighbourhood number of the Mycielski type graphs of graphs. 2018 Academic Publications. -
On the quick estimation of probability of recovery from COVID-19 during first wave of epidemic in India: a logistic regression approach
The COVID-19 pandemic has recently become a threat all across the globe with the rising cases every day and many countries experiencing its outbreak. According to the WHO, the virus is capable of spreading at an exponential rate across countries, and India is now one of the worst-affected country in the world. Researchers all around the world are racing to come up with a cure or treatment for COVID-19, and this is creating extreme pressure on the policy makers and epidemiologists. However, in India the recovery rate has been far better than in other countries, and is steadily improving. Still in such a difficult situation with no effective medicine, it is essential to know if a patient with the COVID-19 is going to recover or die. To meet this end, a model has been developed in this article to estimate the probability of a recovery of a patient based on the demographic characteristics. The study used data published by the Ministry of Health and Family Welfare of India for the empirical analysis. Hemlata Joshi, S. Azarudheen, M. S. Nagaraja, Singh Chandraketu. -
On the Non-Inverse Graph of a Group
Let (G, ?) be a finite group and S = {u G|u u-1}, then the inverse graph is defined as a graph whose vertices coincide with G such that two distinct vertices u and v are adjacent if and only if either u ? v S or v ? u S. In this paper, we introduce a modified version of the inverse graph, called i?-graph associated with a group G. The i?-graph is a simple graph with vertex set consisting of elements of G and two vertices x, y ? are adjacent if x and y are not inverses of each other. We study certain properties and characteristics of this graph. Some parameters of the i?-graph are also determined. 2022 Javeria Amreen et al., published by Sciendo. -
On the Motion of Non-Newtonian EyringPowell Fluid Conveying Tiny Gold Particles Due to Generalized Surface Slip Velocity and Buoyancy
In the painting industry, space science and biomedical science, the nature of relaxation in the flow of non-Newtonian fluid (i.e. blood) containing gold (Ag) suits the characteristics of EyringPowell fluid flow induced by generalized surface slip velocity and buoyancy. However, flow of various non-Newtonian fluids on the horizontal surface of a slanted paraboloid of revolution objects (i.e. rocket, as in space science), over a bonnet of a car and over a pointed surface of an aircraft is of importance to experts in all these fields. In this article, the analysis of the motion within the thin layer formed on a horizontal object which is neither a perfect horizontal nor vertical and neither an inclined surface nor a cone/wedge is presented. The transformed governing equations which model the flow was non-dimenzionalized, parameterized and solved numerically using a well-known RungeKutta integration procedure along with shooting technique. The influence of increasing the magnitude of major parameters on the temperature distribution, local heat transfer rate, concentration of the fluid, local skin friction coefficient and velocity of the flow are illustrated graphically and discussed. Velocity slip parameter is found to be a decreasing function of temperature distribution across the flow. Heat transfer rate (NuxRex-1/2) at the wall (?= 0) is an increasing function of velocity slip parameter. Maximum coefficient of concentration of homogeneous bulk fluid at the wall exists at larger values of the emerged velocity slip and volume fraction parameters. 2018, Springer Nature India Private Limited. -
On the Maximization of Some Graph Coloring Problems
A graph coloring problem involves labeling the vertices or edges in a graph with newlinecolors or numbers subject to some constraints. The most frequently known graph newlinecoloring problems are the ones that usually minimize the number of colors used in newlinecoloring the vertices or edges. The chromatic number of a graph G, denoted by and#967;(G), is the least number of colors used in a proper coloring of G. The chromatic sum of a graph G, denoted as P(G), was introduced in [1], which is to and the smallest possible coloring sum in a proper coloring of the graph G using natural numbers. Lately, a few studies have endured in a distinct area of the literature where the number of colors used in a graph coloring problem is maximized under certain conditions. Some of these works have applications in network sciences. newlineThe concerned study focuses on the maximization of three dierent edge coloring newlineconcepts, viz., the vertex induced kand#8722;edge coloring, vertex incident kand#8722;edge coloring, newlineand edge incident 2and#8722;edge coloring of a simple connected graph G, where k and#8805; 2. The newlinenumber of colors assigned to the edges of the graph G has been maximized under certain conditions. The vertex induced kand#8722;edge coloring and the vertex incident newlinekand#8722;edge coloring concepts are the generalized version of the edge coloring approach newlineintroduced and studied in [2]. Furthermore, the concept of the achromatic sum of a graph G has also been introduced here. This concept is to and the greatest possible coloring sum of the graph G in an improper edge coloring using natural numbers. An extensive study newlineon three achromatic sums, namely the vertex induced 2and#8722;edge coloring sum, the vertex incident 2and#8722;edge coloring sum, and the edge incident 2and#8722;edge coloring sum are carried out. A few bounds for these parameters on a simple connected graph G and the exact values for some elementary graph classes have been investigated. A few comparative results between some of these parameters have also been obtained.