Journal of Scientific Research https://www.banglajol.info/index.php/JSR <p>Published by the Faculty of Sciences, University of Rajshahi. Full-text articles available from <a title="Current issue of JSR" href="/index.php/JSR/issue/archive" target="_self">ARCHIVES</a>.</p> <p>Journal of Scientific Research is included on <a title="DOAJ" href="https://doaj.org/toc/2070-0245" target="_blank" rel="noopener">DOAJ</a>.</p> Faculty of Sciences, Rajshahi University en-US Journal of Scientific Research 2070-0237 <p>© Journal of Scientific Research</p><p><a href="http://creativecommons.org/licenses/by-sa/4.0/" rel="license"><img src="https://i.creativecommons.org/l/by-sa/4.0/88x31.png" alt="Creative Commons License" /></a></p><p>Articles published in the "Journal of Scientific Research" are Open Access articles under a <span id="OBJ_PREFIX_DWT52_com_zimbra_url" class="Object"><a href="https://creativecommons.org/licenses/by-sa/4.0/" target="_blank">Creative Commons Attribution-ShareAlike 4.0 International license</a> </span>(CC BY-SA 4.0). This license permits use, distribution and reproduction in any medium, provided the original work is properly cited and initial publication in this journal. In addition to that, users must provide a link to the license, indicate if changes are made and distribute using the same license as original if the original content has been remixed, transformed or built upon.</p> Study of Molecular Interaction in Aqueous KCl at Different Temperatures https://www.banglajol.info/index.php/JSR/article/view/44977 <p>Ultrasonic velocity, density, viscosity, and electrical conductivity have been measured for an aqueous solution of KCl at different concentrations and temperatures, the frequency is maintained at a constant value. Using the above experimental data, parameters such as Rao's constant, Wada's constant, solvation number, and surface tension were calculated and the molecular interactions between molecules of KCl and water at different temperatures was studied. Using Walden's plot, the ionicity of the solution was also studied.</p> M. K. Praharaj ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 1 8 10.3329/jsr.v13i1.44977 Effect of Deposition Time on Structural and Optoelectronic Properties of Flower-Like Nanostructured PbS Thin Films https://www.banglajol.info/index.php/JSR/article/view/47240 <p>Polycrystalline nanostructured PbS thin films are deposited onto soda-lime glass substrates by the method of chemical bath deposition (CBD) at different duration of deposition time. The structure and surface morphology of the films are characterized by X-ray diffraction (XRD) and field effect scanning electron microscopy (FE-SEM). XRD pattern exhibits polycrystalline structure with preferential orientation along (200) direction, parameters such as crystallite size, lattice constant, lattice-strain and dislocation density are calculated. The FE-SEM images show appearance of flower like structure on formation of PbS films which is indicative of suitability in gas sensing applications. Studies on optical properties carried out by UV-Vis spectroscopy measurements show bandgap in the range 1.65eV – 1.41eV. The photoluminescence spectra of the films exhibit two peaks centered at around 613 nm and 738 nm after excitation at 450 nm. Electrical studies from Hall measurements indicate the carrier concentration and mobility of the PbS samples corroborate the variations in the conductivity.</p> N. H. Sheeba A. Namitha K. M. Ramsiya T. M. Ashitha R. Suhail ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 9 20 10.3329/jsr.v13i1.47240 Phonon Dynamics and Acoustic and Thermodynamic Properties of Pt<sub>57.5</sub>Cu<sub>14.7</sub>Ni<sub>5.3</sub>P<sub>22.5</sub> Bulk Metallic Glass https://www.banglajol.info/index.php/JSR/article/view/47327 <p>The phonon dispersion curves for Pt<sub>57.5</sub>Cu<sub>14.7</sub>Ni<sub>5.3</sub>P<sub>22.5</sub> bulk metallic glass (BMG) are computed employing various dielectric screenings using the simple model given by Bhatia and Singh. The force constants <em>β</em> and <em>δ</em> for computing the dispersion curves are calculated from the elastic constants i.e. bulk modulus (<em>B</em>) and shear modulus (<em>G</em>) along with the calculated value of force constant <em>κ<sub>e</sub></em> of the material of the glass for the first time. The results of the phonon dispersion curves show appropriate behavior in the long wavelength region in detail for both the longitudinal and transverse modes and give insight regarding the acoustic and thermal properties of the BMG. The transverse sound velocity and the longitudinal velocities with various dielectric screening are calculated from the dispersion curves in the long wavelength region. The corresponding thermodynamic property (Debye temperature) is calculated for different dielectric screenings. The theoretical results predicted are in a good agreement with the reported data in the literature for the Pt<sub>57.5</sub>Cu<sub>14.7</sub>Ni<sub>5.3</sub>P<sub>22.5</sub> BMG and may be used for correlating other properties.</p> R. R. koireng P. C. Agarwal A. Gokhroo ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 21 29 10.3329/jsr.v13i1.47327 Study of Carbon Nanotubes with a Casson Fluid in a Vertical Channel of Porous Media under MHD and Dufour Effect https://www.banglajol.info/index.php/JSR/article/view/47458 <p>An analysis is conducted to investigate the problem of heat/mass transfer in MHD free convective flow of Casson-fluid in a vertical channel embedded with saturated porous medium past through carbon nanotubes in the form of single-wall carbon nanotubes (SWCNTs) and multiple-wall carbon nanotubes (MWCNTs) with engine oil as base fluid. In this article, the impact of CNT’s on velocity, temperature, shear stress and rate of heat transfer of the nanofluid has been investigated and studied graphically for the effects of different key physical parameters involved. The validity of this flow model is presented and is found satisfactory agreement with published results. The results state that, fluid velocity accelerates for greater values of Casson parameter and nanoparticles volume fraction, while thermal radiation (R) and heat generation (Q) assume a significant role in CNT's. Applications of this study arise in broad area of science and engineering such as thermal conductivity, energy storage, biomedical applications, air and water filtration, fibers and fabrics.</p> S. Hazarika S. Ahmed ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 31 45 10.3329/jsr.v13i1.47458 Smart Interrogation System by Detection of Visual Focus of Attention https://www.banglajol.info/index.php/JSR/article/view/47481 <p>The paper presents an approach to detect and control the focus of attention of the suspect using his/her eye gaze and head movement direction to build up an automatic interrogation system- specially to detect lies. To this point, we classified interrogation conversation into different criteria and identified the fatal ones. At first, we conducted psychological experiments on the sampled population to detect the different parameters connected with various symptoms when the suspect tells lies and build our knowledgebase with the results. This knowledgebase helps the system to make strategic decisions and to optimize accuracy. A monitoring camera captures continuous interrogation and feeds the frames to our proposed system. 3D head tracker is used to track the head from image and Active Shape Model (ASM) is utilized to localize face points. Vector Field of Image Gradient (VFIG) is calculated to track the eyeball and its rotation within the eye area. Random eye and head movement, change of eyebrow at the critical level of questionnaire provide us the possibility of detecting lies. Finally, experiments are conducted in a controlled environment to validate our psychological findings.&nbsp;</p> P. P. Debnath M. G. Rashed D. Das M. R. Basar ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 47 58 10.3329/jsr.v13i1.47481 A Reliable Computational Algorithm for Solving Fractional Biological Population Model https://www.banglajol.info/index.php/JSR/article/view/47521 <p>In this work, authors obtained the series solution of nonlinear fractional partial differential equations, which is emerging in a spatial diffusion of biological population model using Elzaki transform homotopy perturbation method (ETHPM). The Elzaki transform homotopy perturbation method is a combined form of the Elzaki transform and homotopy perturbation method. Three test illustrations are used to show the proficiency and accuracy of the projected method. It has been observed that the proposed technique can be widely employed to examine other real world problems. The results obtained with the help of the proposed technique are plotted for different fractional orders.</p> A. Devi M. Jakhar ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 59 71 10.3329/jsr.v13i1.47521 Some Results on the Sandor-Smarandache Function https://www.banglajol.info/index.php/JSR/article/view/47721 <p>Sandor introduced a new Smarandache-type function, denoted by <em>SS</em>(<em>n</em>), and is called the Sandor-Smarandache function. When <em>n</em> is an odd (positive) integer, then <em>SS</em>(<em>n</em>) has a very simple form, as has been derived by Sandor himself. However, when <em>n</em> is even, then the form of SS(<em>n</em>) is not simple, and remains an open problem. This paper finds <em>SS</em>(<em>n</em>) for some special cases of <em>n</em>. Particular attention is given to values of the general forms <em>SS</em>(2<em>mp</em>), <em>SS</em>(6<em>mp</em>), <em>SS</em>(60<em>mp</em>) and <em>SS</em>(420<em>mp</em>), where <em>m</em> is any (positive) integer and <em>p</em> is an odd prime. Some particular cases have been treated in detail. In Section 4, some remarks are observed.</p> S. M. S. Islam A. A. K. Majumdar ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 73 84 10.3329/jsr.v13i1.47721 Realization of Inverse Active Filters Using Single Current Differencing Buffered Amplifier https://www.banglajol.info/index.php/JSR/article/view/47766 <p>The authors introduce a new single current differencing buffered amplifier (CDBA) based inverse filter configuration. By appropriate selection of admittances, different inverse filter circuits like inverse high-pass (IHP) circuit, inverse low-pass (ILP) circuit, inverse band-reject (IBR) circuit and inverse band-pass (IBP) circuit can be realized from the same configuration. The capacitors used here are grounded/virtually grounded for all the realizations. The performances of the proposed filters have been judged by using CMOS structure of CDBA with TSMC 0.35 µm technology as well as by using the available IC of current feedback operational amplifier (CFOA) i.e. AD844 based CDBA. The simulation results agreed well with the theoretical results. Monte-Carlo simulation has also been performed to check the robustness of the proposed configuration.</p> T. K. Paul S. Roy R. R. Pal ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 85 99 10.3329/jsr.v13i1.47766 Export Trend of Ready Made Garments (RMG) Sector of Bangladesh https://www.banglajol.info/index.php/JSR/article/view/47810 <p>Ready-Made Garments (RMG) sector has greater importance than any other sector in Bangladesh in terms of growth, employment, foreign exchange earnings and Gross Domestic Product (GDP). The objective of this study is to determine the export trend of the RMG sector in Bangladesh by using different trend models. To serve the objectives of the study, time-series data of RMG sectors has been used for the period 1985-2018. Among several trend models, the Semi-log Parabolic Trend model is found to be the best-fitted model for determining the trend of RMG exports. From the empirical results of the study, it is observed that RMG exports have a significant upward trend for the period 1985-2018 with a growth rate of 8.76 % in 2018. The forecasted RMG export will be nearly 31712.82 million USD in the financial year 2022-23. The findings of the study will help the government, NGO’s and policymakers to undertake necessary steps for the progress of this sector.</p> M. S. Hossain M. T. Uddin ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 101 110 10.3329/jsr.v13i1.47810 Dufour Effect on MHD Free Convection Heat and Mass Transfer Effects Flow over an Inclined Plate Embedded in a Porous Medium https://www.banglajol.info/index.php/JSR/article/view/48174 <p>The aim of this study is to present an exact analysis the effect of heat generation parameter and Dufour number on the magneto hydrodynamic (MHD) free convection flow of an electrically conducting incompressible viscous fluid over an inclined plate embedded in a porous medium. The impulsively started plate with variable temperature and mass diffusion is considered. The dimensionless momentum equation coupled with the energy and mass diffusion equations are analytically solved using the closed analytical method. Expressions for velocity, temperature and concentration fields are obtained. They satisfy all imposed initial and boundary conditions and can be reduced, as special cases, to some known solutions from the literature. Expressions for skin friction, Nusselt number and Sherwood number are also obtained. Finally, the effects of parameters on velocity, temperature and concentration profiles and skin friction coefficient are graphically displayed.</p> <p><strong>&nbsp;</strong></p> S. H. Islam P. Begum D. Sarma ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 111 123 10.3329/jsr.v13i1.48174 Geochemical Analysis of Sediments from Sahaiawei-1 Well of the Northern Delta Depobelt in the Niger Delta Basin, Nigeria https://www.banglajol.info/index.php/JSR/article/view/48455 <p>Geochemical analysis of sediments from Sahaiawei-1 Well of the Northern Delta Depobelt in the Niger Delta Basin was carried out to classify the sediments, determine the provenance, tectonic setting and depositional environment. Twenty (20) ditch cutting samples between 1500 and 10730 ft. were subjected to X-ray fluorescence analysis to determine the elemental composition.&nbsp; The result for the classification of the sediments shows that the sediments were classified as Fe-shale and Fe-sand. The discriminant function diagrams for provenance signature and tectonic setting show that the sediments were plotted within the quartzose sedimentary provenance and passive continental margin tectonic setting fields respectively. The depositional environment using inorganic geochemistry shows that the sediments were deposited with in the continental, transitional and marine environments. This research has provided up to date information on the geochemistry of the Northern Delta Depobelt which would help in hydrocarbon exploration in the area.</p> K. Itiowe F. A. Lucas E. O. Avwenagha ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 125 135 10.3329/jsr.v13i1.48455 Bianchi Type-<i>VI</i><sub>0</sub> Cosmological Model with Special Form of Scale Factor in Sen-Dunn Theory of Gravitation https://www.banglajol.info/index.php/JSR/article/view/48479 <p>A Bianchi Type-VI<sub>0</sub> cosmological model with a special form of scale factor is studied. Einstein field equations in Sen-Dunn theory are obtained and solved for exact solutions. This solution gives a scenario of the dark energy model which tends to a ɅCDM model. The physical and geometrical properties are also obtained and analyzed with the present day observations.</p> D. Basumatay M. Dewri ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 137 143 10.3329/jsr.v13i1.48479 Restrained Edge Domination Number of Some Path Related Graphs https://www.banglajol.info/index.php/JSR/article/view/48520 <p>For a graph <em>G</em> = <em>(V,E)</em>, a set&nbsp; S <dfn class="glossary"><span class="texhtml">⊆</span></dfn> V(S <dfn class="glossary"><span class="texhtml">⊆</span></dfn> E) is a restrained dominating (restrained edge dominating) set if every vertex (edge) not in <em>S</em> is adjacent (incident) to a vertex (edge) in <em>S</em> and to a vertex (edge) in V - S(E-S). The minimum cardinality of a restrained dominating (restrained edge dominating) set of <em>G</em> is called restrained domination (restrained edge domination) number of <em>G</em>, denoted by &nbsp;γ<sub>r</sub> (G) (γ<sub>re</sub>(G). The restrained edge domination number of some standard graphs are already investigated while in this paper the restrained edge domination number like degree splitting, switching,&nbsp; square and middle graph obtained from path.</p> S. K. Vaidya P. D. Ajani ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 145 151 10.3329/jsr.v13i1.48520 Contact Resistance Induced Variability in Graphene Field Effect Transistors https://www.banglajol.info/index.php/JSR/article/view/48948 <p>The success of the graphene field-effect transistor (GFET) is primarily based on solving the problems associated with the growth and transfer of high-quality graphene, the deposition of dielectrics and contact resistance. The contact resistance between graphene and metal electrodes is crucial for the achievement of high-performance graphene devices. This is because process variability is inherent in semiconductor device manufacturing. Two units, even manufactured in the same batch, never show identical characteristics. Therefore, it is imperative that the effect of variability be studied with a view to obtain equivalent performance from similar devices. In this study, we undertake the variability of source and drain contact resistances and their effects on the performance of GFET. For this we have used a simulation method developed by us. The results show that the DC characteristics of GFET are highly dependent on the channel resistance. Also the ambipolar characteristics are strongly affected by the variation of source and drain resistances. We have captured their impact on the output as well as transfer characteristics of a dual gate GFET.</p> S. Behera S. R. Pattanaik G. Dash ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 153 163 10.3329/jsr.v13i1.48948 Generation, Composition and Management of Municipal Solid Waste at Rudraprayag, Garhwal Himalaya https://www.banglajol.info/index.php/JSR/article/view/46853 <p>The key objective of the current research effort was to investigate the generation and composition of the municipal solid waste and to assess the recent management practices for solid waste management. The study area was divided into nine wards and four zones on the basis of population size, their economic and living standards. The total solid waste generation during the study period was around 4-5 tonnes per day. The qualitative solid waste analysis of Rudraprayag reveals that it includes the biodegradable, non-biodegradable and inert waste. However, the quantitative solid waste analysis reveals that the highest generation of biodegradable waste was found in February (89.16 %) and lowest in May (79.06 %). Non-biodegradable waste was recorded highest during March (25.72 %) and lowest during June (7.73 %). The percentage of inert waste was maximum during April (2.87 %) minimum during June (0.037 %). The total waste generation was found maximum during February which was 5883.983 g. However, it was found minimum during May which was 2596.034 g.</p> S. Sharma C. Prasad R. Singh - Anuradha A. Deep R. Kumar ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 165 182 10.3329/jsr.v13i1.46853 Synthesis, Characterization and In-Silico Analysis of New 2-Pyrazolines https://www.banglajol.info/index.php/JSR/article/view/46995 <p>Heterocyclic compounds such as pyrazolines, pyrimidines, oxazole and isoxazole exhibit different pharmacological activities. The current study involves synthesis of new 2-pyrazolines. The synthesis involves the cyclocondensation reaction of substituted chalcones with (4-fluorophenylthio)acetic acid hydrazide (FTAH) under reflux. The chalcones (C1-C7 / 1a-1g) were synthesized from the reaction of substituted acetophenone with substituted benzaldehyde and FTAH was prepared from 4-fluro thiophenol. New 2-pyrazolines were obtained in good yields (60-70 %). All the compounds were characterized by FT-IR, 1H, 13C NMR and mass spectra. PASS analysis was carried out for the 2-pyrazolines synthesized (P1-P7 / 3a-3g).</p> T. Saroja R. M. Ezhilarasi V. Selvamani S. Mahalakshmi ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 183 194 10.3329/jsr.v13i1.46995 Comparative Antimicrobial Study of Different Parts of <i>Ocimum americanum</i> L., <i>O. basilicum</i> L. and <i>O. sanctum</i> L. in Comparison to Standard Antibiotics Collected from Dibrugarh, Assam https://www.banglajol.info/index.php/JSR/article/view/47322 <p>Lamiaceae members are commonly used in ethno-medicinal practices of our country. The in vitro antibacterial and antifungal activity of various solvents extracts of different aerial parts of <em>Ocimum americanum</em> L., <em>O. basilicum</em> L. and <em>O. sanctum</em> L. wereassessed on standard bacterial and fungal strains using standard laboratory methods. Extracts from <em>O. americanum</em> have inhibitory activity against <em>B. subtilis, B. cereus</em> and <em>S. aureus</em>.Acetone extracts of <em>O. basilicum</em> and <em>O. sanctum</em> were found to be more potent being capable of exerting significant inhibitory activities against majority of the bacteria investigated. Acetone extract of young inflorescence of <em>O. americanum</em> showed highest antibacterial activity against <em>B. cereus</em> (14±1mm) which was also higher (10±1mm) than the inhibition of standard Clotrimazole (10mcg). Hot petroleum ether extract of mature leaves of <em>O. basilicum</em> showed highest activity against <em>E. coli</em> (16±2mm) which was also higher than the inhibition ofAmpicillin, Streptomycitin, Erythromycin.Petroleum ether extract of young leaves of <em>O. sanctum</em> recorded highest inhibition against <em>P. vulgaris</em> (20±2mm). Presence of tannins, flavonoids, saponins, phenols in all the parts of the plants. Use of different parts instead of using whole plant will help in sustainable management of these medicinal plants.</p> J. Chetia L. R. Saikia S. Upadhyaya E. Khatiwora A. Bawri ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 195 208 10.3329/jsr.v13i1.47322 Formulation, Development and Evaluation of Bisoprolol Sustained Release Tablets https://www.banglajol.info/index.php/JSR/article/view/47324 <p>Bisoprolol is a type of antihypertensive drug (β-blocker). It is a poorly water-soluble and highly permeable drug that belongs to class II biopharmaceutical classification. This investigation represents the formulation development of bisoprolol to sustain the drug release. Different types of polymers like hypromellose, xanthan gum, avicel, poly ethylene glycol (PEG) were used in this study. Three different formulations were developed by using different excipients at various ratios. The granules were evaluated for bulk density, tapped density, flow property whereas tablets were evaluated for thickness, hardness, weight variation, compressibility index, uniformity of content, disintegration time, and drug release profile. The concentration of the diffused drug was measured using a UV-visible spectrophotometer at λ<sub>max</sub>= 225 nm. Granules showed good flow ability and all the formulations passed the quality. Among all the formulations, F-2 and F-3 showed better efficiency. PEG along with hypermellose, and guar gum showed a good combination for sustaining the drug release</p> M. Masum M. A. R. Ripon D. R. Bhowmik M. T. Amin S. Arefin M. S. Hossain ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 209 219 10.3329/jsr.v13i1.47324 Glucopyranoside Dipentanoyl Esters: Synthesis, PASS Predication, Antimicrobial and <i>In Silico</i> ADMET Studies https://www.banglajol.info/index.php/JSR/article/view/48147 <p>Dimolar pentanoylation of methyl α-D-glucopyranoside using direct method furnished the 2,6-di-<em>O</em>-pentanoate indicating regioselectivity at C-6 and C-2 positions. To develop glucopyranoside based potential antimicrobial agents, 2,6-di-<em>O</em>-pentanoate was further converted into eight newer 3,4-di-<em>O</em>-acyl esters reasonably in good yields. Both prediction of activity spectra for substances (PASS) and <em>in vitro</em> antimicrobial activity test established them as better antifungals than antibacterials. PASS predication also indicated that these sugar esters (SEs) are more potent as anticarcinogenic agents than as antioxidant agents. Structure activity relationship along with <em>in silico</em> ADMET studies clearly indicated that combination of pentanoyl (C5) and lauroyl (C12) in the glucopyranoside framework could be a potential antifungal agent especially against <em>Macrophomina phaseolina</em>.</p> M. M. Matin S. A. Chowdhury M. M. H. Bhuiyan S. M. A. Kawsar M. A. Alam ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 221 235 10.3329/jsr.v13i1.48147 Piper Nigrum Extract as an Environmentally-Safe Inhibitor for the Prevention of Mild Steel in 1.5 M Nitric Acid Medium https://www.banglajol.info/index.php/JSR/article/view/48353 <p>Piper nigrum has extensively explored for its biological properties and its bioactive phyto-compounds. The corrosion prevention of mild steel by Piper nigrum extract (black pepper) using 1.5 M nitric acid medium was examined by the weight-loss method, scanning electron microscope (SEM) examination. The consequences of the study reveal that the dissimilar concentrations of extract prevent mild steel corrosion in acidic medium. The Inhibition efficiency of the extract is found to vary with concentration, temperature, and time of immersion. The inhibition efficiency of the extract was directly proportional to the concentration but inversely proportional to the temperature. Scanning electron microscope experiments exhibit the adsorption of the inhibitory properties of black pepper extract on the surface of the mild steel and show the evidence for the protection of Mild steel by the eco-friendly inhibitor. FTIR values also show evidence for the inhibition of Mild Steel.</p> N. Balamurugapandian ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 237 242 10.3329/jsr.v13i1.48353 Enhancement of Electrical Conductivity of Polyaniline Synthesized by using Carbon Nanofiber https://www.banglajol.info/index.php/JSR/article/view/48356 <p>Carbon nanofiber (CNF) is a very useful additive for improving the performance of polymer matrix composites, but the performance has sometimes been interrupted by limits appear within composite processing. Recently, CNF based polymer composites are intensely considered as promising materials in many application fields, such as electrical devices, electrode materials for batteries, supercapacitors, sensors, etc. Among these, the electrical conductivity is always the first priority need to be considered. Polyaniline (PANI) and PANI-CNF composites are synthesized by chemical oxidative polymerization of aniline monomers in acidic media. The electrical conductivity of PANI-CNF composites were found varies with the degree of amount of CNF under the effect of multiple factors such as the concentration of aniline monomer, reaction media, oxidant, reaction temperature, reaction time, etc. The maximum electrical conductivity was found 3.7131 S/cm of the PANI-CNF composite coming from the polymerization of aniline with 0.05 g CNF. The results of the synthesis also demonstrated that CNF can be an effective material to prepare electrically conducting polymer composites with ordered nanostructures.</p> M. M. Rahman D. R. Sarker M. M. Rahman M. O. Faruk ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 243 252 10.3329/jsr.v13i1.48356 Non-covalent Interactions Directed Rearrangement of Lactones to Pyrones: A Computational Study on the Mechanistic Insights of Solvent Assisted Gold(I) Catalyzed Reactions https://www.banglajol.info/index.php/JSR/article/view/48371 <p>The mechanism of gold(I) catalyzed cycloisomerization of lactones to pyrones was analyzed by performing DFT study using B3LYP method with LanL2DZ basis set for Au and 6-31g(d) basis set for all other atoms. The potential energy surface of the reaction was scanned to know the preferred path for the formation of products under gas phase. The effects of solvent using acetonitrile, dichloromethane and toluene are explored as these solvents are reported to play a crucial role in the final product formation. The crossover between the oxophilic and alkynophilic reaction complexes, R-O and R-C, is found to be the major driving force which directs the product formation. While the larger energy gap between R-O and R-C leads to pyrone formation, the smaller difference and in turn the rapid crossover between R-O and R-C leads to the formation of decarboxylation adduct. Counterion plays a major role throughout the reaction. The atoms in molecules analysis on R-C using implicit as well as explicit solvent gave reason for the observed experimental trends and suggest that the prevailed non-covalent interactions play a substantial role in the product formation.</p> G. Gayatri ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 253 262 10.3329/jsr.v13i1.48371 Gas Chromatographic and Mass Spectroscopic (GC-MS) Analysis of Rhizome of <i>Acorus Calamus</i> Linn. for Identification of Potent Antimicrobial Bio-active Compounds https://www.banglajol.info/index.php/JSR/article/view/48452 <p><em>Acorus calamus</em> Linn. has wide applications as a herbal medicine since its roots, leaves and rhizome exhibit antimicrobial and insecticidal activities. The objective of this study was to identify some compounds in <em>Acorus calamus</em> Linn., which may be responsible for its antimicrobial activity. Gas Chromatography-Mass Spectroscopy (GC-MS) analysis, for investigation of the compounds present, of the petroleum ether extract of <em>Acorus calamus</em> Linn. rhizome suggested presence of five compounds (which showed close match with those of the GC-MS database main library of <em>Novocatalyz</em>) viz., spiro [2,4,5,6,7,7a-hexahydro-2-oxo-4,4,7a-trimethylbenzofuran]-7,2' -(oxirane); 9-octadecenoic acid (Z)-, phenylmethyl ester; shyobunone; asarone [syn. α-asarone]; benzene, 1,2,3-trimethoxy-5-(2-propenyl)-. α-asarone and benzene, 1,2,3-trimethoxy-5-(2-propenyl)- have been reported to be sensitive against plant pathogen and may be responsible for its anti-fungal activity. As per the compound contents of this plant, studies suggest that Acorus calamus Linn. could be a potential herbal medicine against certain microbial diseases.</p> S. Prabha J. Kumar ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 263 273 10.3329/jsr.v13i1.48452 <i>Verbesina encelioides</i>: A Fast Spreading Weed in Semi-arid Regions of North-Western India. Is Climate Change Responsible? https://www.banglajol.info/index.php/JSR/article/view/48844 <p>Alterations in rainfall pattern and rise in temperature along with various anthropogenic disturbances are contributing greatly to biological invasion. In response to ongoing climate change, the sub-tropical and semi-arid regions are shifting towards dry deserts and arid regions, which create a propitious chance for the establishment of highly efficient and opportunistic invasive plant species at the cost of native vegetation. Verbesina encelioides is one of such exploitative plants spreading fast in many semi-arid as well as arid regions of the world. Although the presence of V. encelioides dates back to 1960s, but its emergence as a dominant invasive weed of dry areas is recent in India. The present study focused on the rapid spread of V. encelioides in the north-western states of India owing to its ecological traits as well as changing climate patterns of the country.</p> K. K. Mehal ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 275 282 10.3329/jsr.v13i1.48844 Media Optimization for Production of Recombinant Carrier Protein (CRM197) in <i>Escherichia coli</i> https://www.banglajol.info/index.php/JSR/article/view/48996 <p>Since the advent of vaccines, the mankind has benefited from the same and has been able to curb the mortality rate around the globe. Amongst different types of available vaccines, polysaccharide based vaccines are very widely used against various infectious diseases. The polysaccharide vaccines need to be conjugated with a carrier protein to make the vaccine more immunogenic. Recombinant Escherichia coli cells are the organism of choice for large scale production of a carrier protein because of its widely studied scientific aspects. In the present study, for proof of concept, the recombinant E. coli cells were cultured in Luria-Bertani media to check the expression of rCRM197. At 80L scale, it was observed that when recombinant E. coli cells were grown in a chemically defined media, it resulted in inconsistent growth and a long lag phase. When the defined media was supplemented with yeast extract, the lag phase of the culture was substantially reduced and the maximum growth of the culture was achieved. Protein expression was checked using SDS PAGE (Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis) and Western blot technique. The optimized media resulted in a robust fermentation process to achieve high cell density and maximum biomass for the production of recombinant protein.</p> S. Shukla D. Mishra ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 283 297 10.3329/jsr.v13i1.48996 Utilization of Nanomaterials in Target Oriented Drug Delivery Vehicles https://www.banglajol.info/index.php/JSR/article/view/47690 <p>The present investigation deals with the fundamentals of nanorobots, its fabrication, and possible utilization in a different target-oriented drug delivery vehicles. Details of various types of nanorobots and their specific applications are studied in this research. The use of nanorobots in cancer treatment, target-oriented drug delivery, medical imaging, and in new health sensing devices has also been studied. The mechanism of action of nanorobots for the treatment of cancerous cells as well as the formulation and working functions of some recently studied nanorobots are investigated in this work. This paper reviews the research in finding the suitable nanorobotic materials, different fabrication processes of nanorobots, and the current status of application of nanorobots in biomedical, especially in the treatment of cancers. Superparamagnetic iron oxide nanoparticles (SPIONs) have been observed to be used as novel drug delivery vehicle materials. The future perspectives of nanorobots for the utilization in drug delivery are also addressed herewith.</p> T. K. Mandal V. Patait ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 299 316 10.3329/jsr.v13i1.47690 Recent Development of Trifluoromethyl Reagents: A Review https://www.banglajol.info/index.php/JSR/article/view/48992 <p>Organic molecules having fluorine atom are very important since it increases the lipophilicity that is essential for drug development and additionally strong carbon-fluorine (C-F) bond makes the material unique, especially for material chemistry. Instead of elemental fluorine, recently trifluoromethylated materials (CF3) have drawn considerable attention in the agrochemical and pharmaceutical industries. In the continuous development of the trifluoromethylated reagents, over the last few decades, some trifluoromethylated reagents have been well developed and the efficiency of these reagents for incorporating CF3 group on different types of substrates are also studied. In this article, all types of available trifluoromethylated reagents and their effectiveness on suitable substrates are summarized. Additionally, the methods of synthesizing trifluoromethylated substrates are discussed. Finally, the scopes of the development of new reagents after focusing on the shortcomings of the current reagents are also discussed.</p> A. C. Bhowmick ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2021-01-01 2021-01-01 13 1 317 333 10.3329/jsr.v13i1.48992