Jyrwa L.B.,Assam Don Bosco University |
Bhuyan R.N.,St Anthonys College
Iranian Journal of Ichthyology | Year: 2017
Chocolate Mahseer, Neolissochilus hexagonolepis is an important food and game fish of North Eastern region of the country, particularly the high lands of Meghalaya. Reproductive biology of the species has been done under the climatic condition of Meghalaya to understand the gonadal development. The gonadal structure and development stages of germ cells of N. hexagonolepis are described for both sexes. Five stages of development are described based on the histological characteristics of testis and ovary. The kind of development and the presence of postovulatory follicles in ovaries which still contain developing vitellogenic oocytes suggest that N. hexagonolepis spawns over a relatively prolonged period of time. © 2017 Iranian Society of Ichthyology.
Borgohain R.,Assam Don Bosco University |
Baruah S.,Assam Don Bosco University
IEEE Sensors Journal | Year: 2017
Water is a basic human need, but many people do not have access to clean and safe drinking water. Many people die of waterborne bacterial diseases in the world. The presence of bacterial pathogens in water can be detected by using sophisticated and expensive instruments, which take extensive time for measurement. In contrast to those instrumentation, nanostructure-based devices can be used as instant and cheap bacteria sensors. This paper reports the fabrication of a sensor using ZnO nanorods for detection of two bacterial pathogens, namely Escherichia coli, which is a gram-negative bacteria and Streptococcus pneumonia, which is a gram-positive bacteria present in water at different concentrations. The fabrication of the sensor was done by growing ZnO nanorods hydrothermally on a Cu electrode. The sensor was then tested with some known concentrations of bacteria mixed in water. When bacteria mixed water sample is dropped over the sensor, the electrical resistance of the sensor varies proportionally with bacteria concentration. Maximum responses of 96% and 94.375% at room temperature and minimum detection limits of 1.12% and 1.01% were achieved for 9.15× 108 cells/mL of E. coli and 1.043 × 109 cells/mL of S. pneumonia present in water, respectively. The high sensitivity and dynamic repeatability exhibited by these sensors reveal that ZnO nanorods are promising as sensitive and reliable sensors for detecting bacteria present in water. © 2001-2012 IEEE.
Mahanta D.K.,Assam Engineering College |
Laskar S.,Assam Don Bosco University
Journal of Advanced Dielectrics | Year: 2017
Insulating liquid plays an important role for the life span of the transformer. Petroleum-based mineral oil has become dominant insulating liquid of transformer for more than a century for its excellent dielectric and cooling properties. However, the usage of petroleum-based mineral oil, derived from a nonrenewable energy source, has affected the environment for its nonbiodegradability property. Therefore, researchers direct their attention to renewable and biodegradable alternatives. Palm fatty acid ester, coconut oil, sunflower oil, etc. are considered as alternatives to replace mineral oil as transformer insulation liquid. This paper gives an extensive review of different liquid insulating materials used in a transformer. Characterization of different liquids as an insulating material has been discussed. An attempt has been made to classify different insulating liquids-based on different properties. © 2017 © The Author(s)
Jaisai M.,Asian Institute of Technology |
Baruah S.,Asian Institute of Technology |
Baruah S.,Assam Don Bosco University |
Dutta J.,Asian Institute of Technology |
Dutta J.,Sultan Qaboos University
Beilstein Journal of Nanotechnology | Year: 2012
Paper with antimicrobial properties was developed through in situ growth of ZnO nanorods. The targeted application for this type of paper is in health centers as wallpaper, writing paper, facemasks, tissue paper, etc. The paper was tested on three model microbes, Gram-positive bacteria Staphylococcus aureus, Gram-negative bacteria Escherichia coli and common airborne fungus Aspergillus niger. No viable bacterial colonies or fungal spores could be detected in the areas surrounding test samples of the antimicrobial paper. Gram-negative bacteria Escherichia coli were found to be inhibited in an area that is 239% and 163% the area of the paper sample under different room lighting conditions, i.e., halogen and fluorescent lamp illumination, respectively. For Gram-positive bacteria Staphylococcus aureus the zones of inhibition surrounding the paper samples are 102% and 70%, and for Aspergillus niger, 224% and 183% of the sample area, under similar lighting conditions. © 2012 Jaisai et al.
Baruah S.,Assam Don Bosco University |
Pal S.K.,se National Center For Basic Science |
Dutta J.,Sultan Qaboos University
Nanoscience and Nanotechnology - Asia | Year: 2012
Environmental pollution and industrialization on a global scale have drawn attention to the vital need for developing new hygienically friendly purification technologies. Existing wastewater treatment technologies demand high capital investment and operation & maintenance cost, and large area. Cost-effective treatment of pollutants requires the transformation of hazardous substances into benign forms and the subsequent development of effective risk management strategies from harmful effects of pollutants that are highly toxic, persistent, and difficult to treat. Application of nanotechnology that results in improved water treatment options might include removal of the finest contaminants from water (< 300 nm) and "smart materials" or "reactive surface coatings" with engineered specificity to a certain pollutant that destroy, transform or immobilize toxic compounds. Nanomaterials have been gaining increasing interest in the area of environmental remediation mainly due to their enhanced surface and also other specific changes in their physical, chemical and biological properties that develop due to size effects. Heterogeneous photocatalytic systems via metal oxide semiconductors like TiO2 and ZnO, are capable of operating effectively and efficiently for waste water treatment which has been discussed along with other nanotechnology routes that can be useful for water treatments. Multifunctional photocatalytic membranes using ZnO nanostructures are considered advantageous over freely suspended nanoparticles due to the ease of its removal from the purified water. A short discussion on the study of charge transfer mechanisms during photocatalytic reactions has also been included. © 2012 Bentham Science Publishers.
Sharma U.,Assam Don Bosco University
2014 International Conference on Data Mining and Intelligent Computing, ICDMIC 2014 | Year: 2014
Words can be categorized into different types according to the position of occurrences of vowels and consonants in it. Accordingly we have CV (Consonant-Vowel), VC (Vowel-Consonant), and CVC (Consonant-Vowel-Consonant), CVCC (Consonant-Vowel-Consonant-Consonant), CVVC (Consonant-Vowel-Vowel-Consonant etc type of words in most of the languages. As a first step towards the recognition of any speech signal, it is very much important to study the different types of words using some of the available techniques. Some of the approach which produces reliable and good results are Formant Frequency measure, Mel-frequency cepstral coefficients (MFCC) etc. In this paper, a step has been taken to measure the formant frequency of CV type Bodo words to identify the distinct features of it. Formant Frequency, based on Formant Tracking Model can be defined as the spectral peak of the sound spectrum |P(f)|. © 2014 IEEE.
Laskar S.,Assam Don Bosco University |
Bordoloi S.,Assam Don Bosco University
Optical Fiber Technology | Year: 2016
This paper presents an instrumentation system to measure the degradation in lubricating oil using a bare, tapered and bent multi-mode optical fiber (BTBMOF) sensor probe and a temperature probe. The sensor system consists of (i) a bare, tapered and bent multi-mode optical fiber (BTBMOF) as optical sensor along with a laser source and a LDR (Light Dependent Resistor) as detector (ii) a temperature sensor (iii) a ATmega microcontroller based data acquisition system and (iv) a trained ANN for processing and calibration. The BTBMOF sensor and the temperature sensor are used to provide the measure of refractive index (RI) and the temperature of a lubricating oil sample. A microcontroller based instrumentation system with trained ANN algorithm has been developed to determine the degradation of the lubricating oil sample by sampling the readings of the optical fiber sensor, and the temperature sensor. © 2015 Elsevier Inc.
Baruah S.,Assam Don Bosco University
Lecture Notes in Electrical Engineering | Year: 2015
Extensive use of fossil fuel in industries and automobiles has severely polluted the environment, adversely affecting the ecosystem. The fossil fuel reserves are also dwindling, creating a serious concern in the area of energy generation. With rapid advances in nanotechnology, researchers are putting in their efforts to exploit unique properties of nanomaterials to come up with environmentally friendly energy solutions. The abundantly freely available solar energy is undoubtedly the least utilized form of natural energy. Efficient tapping of solar energy can resolve the energy crisis that our world is currently going through. Solar cells developed using nanomaterials, though still at the infancy stage, will be able to harness solar energy quite efficiently and most importantly, will be able to do it very cheaply. Piezoenergy resulting from physical deformation of near-elastic crystals shows promise as energy source for self-powering of low energy consuming devices. This article discusses the possibility of using nanostructures of a very promising material, zinc oxide (ZnO), for energy generation. ZnO is a wide bandgap semiconductor (3.37 eV) and the absence of a central symmetry in its crystal endows it with piezoelectric property. This material has been successfully used for energy generation and tapping schemes like solar cells, hydrogen generators and piezogenerators, among others. © Springer India 2015.
Sharma B.,Assam Don Bosco University
ACM International Conference Proceeding Series | Year: 2015
Due to intrinsic properties of Mobile Ad hoc Network (MANETs) such as openness, infrastructure less network, dynamic topology, mobility of nodes, lack of centralized monitoring system, lack of secure routing protocol etc., it always suffers from different kind of attacks. There is no clear line of defense to resists the malicious nodes from its route. Moreover, nodes communicate to each other on hop-by-hop fashion. That helps the intruders to sit in between and deliberately disrupt the communication. That degrades the network performance in different levels. This paper contains a distributed cooperative approach to detect a network layered active attack known as gray hole attack. Efficiency of the detection methodology has been shown in terms of detection rate and throughput of the network. © 2015 ACM.
Deka R.K.,Gauhati University |
Paul A.,Assam Don Bosco University
International Journal of Fluid Mechanics Research | Year: 2013
This paper presents an exact solution to the flow of a viscous incompressible fluid past an impulsively started horizontal cylinder in a rotating fluid. Dimensionless governing equations are solved by Laplace transform technique. Expressions of axial and transverse components of velocity, skin friction are derived using Laplace transform technique and effects of rotation parameter and time on these components are shown in graphs. It is demonstrated that the rotation leads to oscillatory motion solely due to rotation for smaller time, while the flow approaches steady state at larger time. © 2013 Begell House, Inc.