International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
Introducation to optical properties and also relation with nano material. As most of the properties are similar for simple and nano material only some fundamental points are changed.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Zno and znopbs heterojunction photo electrochemical cellseSAT Journals
Abstract Photo Electrochemical Cell (PEC) can also be used for splitting of water into hydrogen and Oxygen. Here, ZnO nanorod PEC has been prepared in hydrothermal method and ZnO/PbS quantum dot PEC has been prepared by hydrothermal method and chemical bath deposition method. UV-Visible spectroscopy has been observed. Flat band voltage, bandwidth and majority charge carriers have been calculated from Mott-Schottky. Impedance variation at semiconductor and electrolyte junction has been observed with Electrochemical Impedance Spectroscopy (EIS). Keywords: Hydrothermal, Chemical bath, ZnO/PbS, UV-Vis, Mott-Schottky, EIS.
Optical properties such as UV/vis spectra and polarizability can be predicted with new features in Materials Studio DMol3 5.5. This presenation provides some background on the implementaiton as well as case studies.
Fabrication of semiconductor materials by using electrospinningBecker Budwan
Semiconductor (s/c) is a materials conducts electricity more than an insulators but less than a pure conductors.
Semiconductors are usually very small and complex devices, and can be found in thousands of products such as computers, cell phones and medical equipment.
Introducation to optical properties and also relation with nano material. As most of the properties are similar for simple and nano material only some fundamental points are changed.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Zno and znopbs heterojunction photo electrochemical cellseSAT Journals
Abstract Photo Electrochemical Cell (PEC) can also be used for splitting of water into hydrogen and Oxygen. Here, ZnO nanorod PEC has been prepared in hydrothermal method and ZnO/PbS quantum dot PEC has been prepared by hydrothermal method and chemical bath deposition method. UV-Visible spectroscopy has been observed. Flat band voltage, bandwidth and majority charge carriers have been calculated from Mott-Schottky. Impedance variation at semiconductor and electrolyte junction has been observed with Electrochemical Impedance Spectroscopy (EIS). Keywords: Hydrothermal, Chemical bath, ZnO/PbS, UV-Vis, Mott-Schottky, EIS.
Optical properties such as UV/vis spectra and polarizability can be predicted with new features in Materials Studio DMol3 5.5. This presenation provides some background on the implementaiton as well as case studies.
Fabrication of semiconductor materials by using electrospinningBecker Budwan
Semiconductor (s/c) is a materials conducts electricity more than an insulators but less than a pure conductors.
Semiconductors are usually very small and complex devices, and can be found in thousands of products such as computers, cell phones and medical equipment.
EFFECT OF ULTRAVIOLET RADIATION ON STRUCTURAL PROPERTIES OF NANOWIRESijoejournal
Copper nanowires were prepared through electrochemical template synthesis using Nucleopore polycarbonate membranes having nominal pore sizes of 800nm and 15nm diameter. The 800nm and 15nm nanowires thus grown were viewed under SEM and TEM respectively, while their FCC crystallographic structure was confirmed through X-ray and electron diffraction patterns. The X-ray diffraction peaks indicated strong texturing for (200). The texturing was found to reduce significantly upon exposure to ultraviolet radiation.
Greener cum chemical synthesis and characterization of Mg doped ZnS nanoparti...IJERA Editor
In the present investigations, high-quality Mg doped ZnS nanoparticles were synthesized by Greener cum
chemical process with the assistance of polyvinyl pyrrolidone (PVP) with two different Mg concentrations.
Doping of Mg metal in nanoparticles were found to be a good technique for tuning the band gap of ZnS
nanoparticles. Simultaneously, Mg doping also inhibited the growth of particle size and it decreased from 33.2
nm to 18.3 nm with the increase in doping concentration from 0% to 5%. Band gap was found to rise from 3.12
eV to 3.38 eV and photoluminescence studies exposed that visible Photoluminescence (PL) emission was
improved with doping concentration. The nanoparticles have been characterized by Field Emission Scanning
Electron Microscopy (FESEM), X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy,
Ultra Violet visible (UV–vis) spectroscopy, and Energy Dispersive X-ray Analysis (EDAX).
Gamry’s eQCM 10M™ is a rapid, impedance-scanning electrochemical quartz crystal microbalance (EQCM) that adds a valuable tool in the analytical toolbox of anyone investigating interfacial processes.
EFFECT OF ULTRAVIOLET RADIATION ON STRUCTURAL PROPERTIES OF NANOWIRESijoejournal
Copper nanowires were prepared through electrochemical template synthesis using Nucleopore polycarbonate membranes having nominal pore sizes of 800nm and 15nm diameter. The 800nm and 15nm nanowires thus grown were viewed under SEM and TEM respectively, while their FCC crystallographic structure was confirmed through X-ray and electron diffraction patterns. The X-ray diffraction peaks indicated strong texturing for (200). The texturing was found to reduce significantly upon exposure to ultraviolet radiation.
Greener cum chemical synthesis and characterization of Mg doped ZnS nanoparti...IJERA Editor
In the present investigations, high-quality Mg doped ZnS nanoparticles were synthesized by Greener cum
chemical process with the assistance of polyvinyl pyrrolidone (PVP) with two different Mg concentrations.
Doping of Mg metal in nanoparticles were found to be a good technique for tuning the band gap of ZnS
nanoparticles. Simultaneously, Mg doping also inhibited the growth of particle size and it decreased from 33.2
nm to 18.3 nm with the increase in doping concentration from 0% to 5%. Band gap was found to rise from 3.12
eV to 3.38 eV and photoluminescence studies exposed that visible Photoluminescence (PL) emission was
improved with doping concentration. The nanoparticles have been characterized by Field Emission Scanning
Electron Microscopy (FESEM), X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy,
Ultra Violet visible (UV–vis) spectroscopy, and Energy Dispersive X-ray Analysis (EDAX).
Gamry’s eQCM 10M™ is a rapid, impedance-scanning electrochemical quartz crystal microbalance (EQCM) that adds a valuable tool in the analytical toolbox of anyone investigating interfacial processes.
Cost Analysis of Small Scale Solar and Wind Energy SystemsIJMER
Abstract: The recent dramatic increase in the use of
renewable energy systems leading towards competitive
markets within the various individual renewable energy
systems. The aim of this paper is to prove the hypothesis
i.e. in next few years, when the cost of the solar PV
modules come down below 1$ per Watt, small wind
turbines become more costlier because of the cost of
structures required to support the wind generator. And
also if the threat from the market is not addressed both
technically and commercially, small wind turbine
manufactures will lose the competition to solar PV module
manufactures in the near visible future. Objective of this
paper is to do cost analysis on the industry data and prove
hypothesis and to arrive at the cutoff point, where after the
generating energy from the wind is not economically
feasible. With this cost analysis, author here by alarm for
the small scale wind turbine manufactures to take
necessary measures to survive the competitive markets of
small scale renewable energy systems.
Keywords: Renewable energy, Solar PV, Wind Turbine, Curve Fitting, Cost analysis.
Query Answering Approach Based on Document SummarizationIJMER
The growing of online information obliged the availability of a thorough research in the
domain of automatic text summarization within the Natural Language Processing (NLP)
community.The aim of this paper is to propose a novel approach for a language independent automatic
summarization approach that combines three main approaches. The Rhetorical Structure Theory
(RST), the query processing approach, and the Network Representationapproach (NRA). RST, as a
theory of major aspect for the structure of natural text, is used to extract the semantic relation behind
the text.Query processing approachclassifies the question type and finds the answer in a way that suits
the user’s needs. The NRA is used to create a graph representing the extracted semantic relation. The
output is an answer, which not only responses to the question, but also gives the user an opportunity to
find additional information that is related to the question.We implemented the proposed approach. As a
case study, the implemented approachis applied on Arabic text in the agriculture field. The
implemented approach succeeded in summarizing extension documents according to user's query. The
approach results have been evaluated using Recall, Precision and F-score measures.
Stakeholders’ Perception of the Causes and Effect of Construction Delays on P...IJMER
Indian Construction industry is large, volatile, and requires tremendous capital outlays. Typically, the work offers low rates of return in relation to the amount of risk involved. A unique element of risk in the industry is the manner in which disputes and claims are woven through the fibre of the construction process. Delay is generally acknowledged as the most common, costly, complex and risky problem encountered in construction projects. Because of the overriding importance of time for both the Owner and the Contractor, it is the source of frequent disputes and claims leading to lawsuits. The growing rate of delays is adversely affecting the timely delivery of construction projects. Presently construction industries are facing a lot of problems, considering that a paper assess construction stakeholder’s perception to the causes of delays and its effects on project delivery. And also one case study is considered in this paper to elicit responses from construction stakeholders. The primary aim of this paper is to identify the perceptions of the different parties regarding causes of delays, the allocation of responsibilities and the types of delays, and method of minimizing the construction delays
In this paper the finite element analysis of aHeat Exchanger is done. The geometry was
modelled in CATI A V5 R21 and finite element analysis had been performed in ANSYS12 WB. FE analysis
is was used to determine stress analysis at.
The Effects of Vehicle Speeds on Accident Frequency within Settlements along ...IJMER
Literature provides overwhelming evidence that a strong relationship exist between
vehicle speed and accident risk, and an outcome severity in the event of an accident. Excessive speed
is said to be a major causal factor of road accidents on trunk roads; contributing 60% of all vehicular
accidents. However, speed rationalization measures implemented on a number of trunk roads in
Ghana have realized very little success. This study therefore investigated the effects of vehicle speeds
on accident frequency within settlements along trunk roads. Data was collected on accidents, vehicle
speeds and other road and environment-related features for ninety-nine (99) settlements delineated
from four (4) trunk roads. Correlation analysis was employed to establish useful relationships and
provided insight into the contributions of relevant road and environmental-related variables to the
occurrence of road traffic accidents. Using the Negative Binomial error structure within the
Generalized Linear Model framework, core (flow-based) models were formulated based on accident
data and exposure variables (vehicle mileage, daily pedestrian flow and travel speed). Incremental
addition of relevant explanatory variables further expanded the core models into comprehensive
models. Findings indicate the main risk factors are number of accesses, daily pedestrian flow and
total vehicle kilometers driven, as vehicle speed did not appear to influence the occurrence of road
traffic accidents within settlements along trunk roads. In settlement corridors, mitigating accident
risks should not focus only on traffic calming but rather on measures that reduce pedestrian and
vehicular conflict situations as well as improve conspicuity around junctions
Study of conductivity, optical constants and solid state parameters of thiour...eSAT Journals
Abstract In the present paper single crystals of Thiourea Zinc Sulphate (TZS) have been subjected to conductivity studies, determination of optical constants and fundamental parameters. The dielectric constant and dielectric loss were used to calculate the AC conductivity of the grown crystals over a frequency range 50 Hz to 5 MHz at temperatures 313 K, 323 K and 333 K respectively. The activation energies for the conduction process were determined from the Arrhenius plots for different frequencies. The optical constants such as refractive index, reflectance and susceptibility of the TZS single crystals were evaluated from the Ultra violet-Visible (UV-Vis) spectrum data. The Plasma energy, Penn gap energy, Fermi energy and polarizability of the grown crystals were estimated theoretically using the single crystal X- ray diffraction (XRD) data. Keywords: Conductivity, Activation energy, Refractive index, Penn energy, Polarizability.
Electrical properties of Ni0.4Mg0.6Fe2O4 ferritesIJERA Editor
Ni0.4Mg0.6Fe2O4 Ceramic samples were prepared by conventional double sintering approach and sintered at 1300oC/4 h. These ferrites are further characterized using X-ray diffractometer. The diffraction study reveals that the present compound shows perfect single phase cubic spinel structure. In addition, the behavior of distinct electrical properties such as dielectric constant (ε'), dielectric loss (ε") and ac-conductivity (ζac) as a function frequency as well as temperature is analyzed using the LCR controller.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Studies on in-Doped Zno Transparent Conducting thin FilmsIJRESJOURNAL
ABSTRACT: In this manuscript we have investigated the influences of indium dopants on zinc oxide (ZnO) thin films regarding physico-chemical properties for application in modern conducting devices. As a starting material, Indium (III) chloride, and Zn(CH3COO)2⋅2H2O were used. The complex TSDC spectrum was obtained by submitting the sample to a constant electrical field Ep = 10M V/m during 2 min at a varing polarization temperature of Tmax = 1500C. A minimal sheet resistance with electrical resistivity as low in the range of 10-3 Ω·cm was found for this thin film.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
In this work, an investigation of the steady-state electron transport and low-field electron mobility
characteristics of Wurtzite ZnO and Zn1_xMgxO are examined using the ensemble Monte Carlo model. The
Monte Carlo calculations are carried out using a three-valley model for the systems under consideration. The
following scattering mechanisms, i.e, impurity, polar optical phonon and acoustic phonon are included in the
calculation. The maximum electron drift velocity that is obtained at room temperature for 1023 m-3 donor
concentration is 2.36×107 cms-1 for ZnO in threshold field of 461 kV/cm. While the maximum electron drift
velocity is1.65×107 cms-1 for Zn0.95Mg0.05O in threshold field 861 kV/cm. The maximum electron mobility for ZnO
886 cm2/V.s and for Zn1_xMgxO in variuos amount x=0.05, 0.1 and 0.2 is 304, 132 and 33 cm2/V.s respectively.It
can be seen the peak drift velocity for bulk ZnO is 2.36×107 Cms-1,while for Zn1_xMgxO the peak drift velocity
decreases due to increasing electron effective mass. The electron mobility of Zno is more than ZnMgo alloysat
all temperatures becauseelectron mobility behavior dependence on effective mass and ionized impurity
concentration.
Study of Microstructural, Electrical and Dielectric Properties of La0.9Pb0.1M...Scientific Review SR
The present work studies the microstructural and electrical properties of La0.9Pb0.1MnO3 and La0.8Y0.1Pb0.1MnO3 ceramics synthesized by solid-state route method. Microstructure and elemental analysis of both samples were carried out by field emission scanning electron microscope (FESEM) and energy dispersive spectroscopy (EDS) method, respectively. Phase analysis by X-ray diffraction (XRD) indicated formation of single phase distorted structure. The XRD data were further analyzed by Rietveld refinement technique. Raman analysis reveals that Y atom substitutes La site into the LPMO with shifting of phonon modes. The temperature variation of resistivity of undoped and Y-doped La0.9Pb0.1MnO3 samples have been investigated. The electrical resistivity as a function of temperature showed that all samples undergo an metal-insulator (M-I) transition having a peak at transition temperature TMI. Y-doping increases the resistivity and the metal-insulator transition temperature (TMI) shifts to lower temperature. The temperature-dependent resistivity for temperatures less than metal-insulator transition is explained in terms the quadratic temperature dependence and for T > TMI, thermally activated conduction (TAC) is appropriate. Variation of frequency dispersion in permittivity and loss pattern due to La-site substitution in LPMO was observed in the dielectric response curve.
Similar to Optical and Impedance Spectroscopy Study of ZnS Nanoparticles (20)
A Study on Translucent Concrete Product and Its Properties by Using Optical F...IJMER
- Translucent concrete is a concrete based material with light-transferring properties,
obtained due to embedded light optical elements like Optical fibers used in concrete. Light is conducted
through the concrete from one end to the other. This results into a certain light pattern on the other
surface, depending on the fiber structure. Optical fibers transmit light so effectively that there is
virtually no loss of light conducted through the fibers. This paper deals with the modeling of such
translucent or transparent concrete blocks and panel and their usage and also the advantages it brings
in the field. The main purpose is to use sunlight as a light source to reduce the power consumption of
illumination and to use the optical fiber to sense the stress of structures and also use this concrete as an
architectural purpose of the building
Developing Cost Effective Automation for Cotton Seed DelintingIJMER
A low cost automation system for removal of lint from cottonseed is to be designed and
developed. The setup consists of stainless steel drum with stirrer in which cottonseeds having lint is mixed
with concentrated sulphuric acid. So lint will get burn. This lint free cottonseed treated with lime water to
neutralize acidic nature. After water washing this cottonseeds are used for agriculter purpose
Study & Testing Of Bio-Composite Material Based On Munja FibreIJMER
The incorporation of natural fibres such as munja fiber composites has gained
increasing applications both in many areas of Engineering and Technology. The aim of this study is to
evaluate mechanical properties such as flexural and tensile properties of reinforced epoxy composites.
This is mainly due to their applicable benefits as they are light weight and offer low cost compared to
synthetic fibre composites. Munja fibres recently have been a substitute material in many weight-critical
applications in areas such as aerospace, automotive and other high demanding industrial sectors. In
this study, natural munja fibre composites and munja/fibreglass hybrid composites were fabricated by a
combination of hand lay-up and cold-press methods. A new variety in munja fibre is the present work
the main aim of the work is to extract the neat fibre and is characterized for its flexural characteristics.
The composites are fabricated by reinforcing untreated and treated fibre and are tested for their
mechanical, properties strictly as per ASTM procedures.
Hybrid Engine (Stirling Engine + IC Engine + Electric Motor)IJMER
Hybrid engine is a combination of Stirling engine, IC engine and Electric motor. All these 3 are
connected together to a single shaft. The power source of the Stirling engine will be a Solar Panel. The aim of
this is to run the automobile using a Hybrid engine
Fabrication & Characterization of Bio Composite Materials Based On Sunnhemp F...IJMER
The present day technology demands eco-friendly developments. In this era the
composite material are playing a vital roal in different field of Engineering .The composite materials
are using as a principle materials. Nowaday the composite materials are utilizing as a important
component of engineering field .Where as the importance of the applications of composites is well
known, but thrust on the use of natural fibres in it for reinforcement has been given priority for some
times. But changing from synthetic fibres to natural fibres provides only half green-composites. A
partial green composite will be achieved if the matrix component is also eco-friendly. Keeping this in
view, a detailed literature surveyed has been carried out through various issues of the Journals
related to this field. The material systems used are sunnhemp fibres. Some epoxy and hardener has
been also added for stability and drying of the bio-composites. Various graphs and bar-charts are
super-imposed on each other for comparison among themselves and Graphs is plotted on MAT LAB
and ORIGIN 6.0 software. To determining tensile strengths, Various properties for different biocomposites
have been compared among themselves. Comparison of the behaviour of bio-composites of
this work has been also compare with other works. The bio-composites developed in this work are
likely to get applications in fall ceilings, partitions, bio-degradable packagings, automotive interiors,
sports things (e.g. rackets, nets, etc.), toys etc.
Geochemistry and Genesis of Kammatturu Iron Ores of Devagiri Formation, Sandu...IJMER
The Greenstone belts of Karnataka are enriched in BIFs in Dharwar craton, where Iron
formations are confined to the basin shelf, clearly separated from the deeper-water iron formation that
accumulated at the basin margin and flanking the marine basin. Geochemical data procured in terms of
major, trace and REE are plotted in various diagrams to interpret the genesis of BIFs. Al2O3, Fe2O3 (T),
TiO2, CaO, and SiO2 abundances and ratios show a wide variation. Ni, Co, Zr, Sc, V, Rb, Sr, U, Th,
ΣREE, La, Ce and Eu anomalies and their binary relationships indicate that wherever the terrigenous
component has increased, the concentration of elements of felsic such as Zr and Hf has gone up. Elevated
concentrations of Ni, Co and Sc are contributed by chlorite and other components characteristic of basic
volcanic debris. The data suggest that these formations were generated by chemical and clastic
sedimentary processes on a shallow shelf. During transgression, chemical precipitation took place at the
sediment-water interface, whereas at the time of regression. Iron ore formed with sedimentary structures
and textures in Kammatturu area, in a setting where the water column was oxygenated.
Experimental Investigation on Characteristic Study of the Carbon Steel C45 in...IJMER
In this paper, the mechanical characteristics of C45 medium carbon steel are investigated
under various working conditions. The main characteristic to be studied on this paper is impact toughness
of the material with different configurations and the experiment were carried out on charpy impact testing
equipment. This study reveals the ability of the material to absorb energy up to failure for various
specimen configurations under different heat treated conditions and the corresponding results were
compared with the analysis outcome
Non linear analysis of Robot Gun Support Structure using Equivalent Dynamic A...IJMER
Robot guns are being increasingly employed in automotive manufacturing to replace
risky jobs and also to increase productivity. Using a single robot for a single operation proves to be
expensive. Hence for cost optimization, multiple guns are mounted on a single robot and multiple
operations are performed. Robot Gun structure is an efficient way in which multiple welds can be done
simultaneously. However mounting several weld guns on a single structure induces a variety of
dynamic loads, especially during movement of the robot arm as it maneuvers to reach the weld
locations. The primary idea employed in this paper, is to model those dynamic loads as equivalent G
force loads in FEA. This approach will be on the conservative side, and will be saving time and
subsequently cost efficient. The approach of the paper is towards creating a standard operating
procedure when it comes to analysis of such structures, with emphasis on deploying various technical
aspects of FEA such as Non Linear Geometry, Multipoint Constraint Contact Algorithm, Multizone
meshing .
Static Analysis of Go-Kart Chassis by Analytical and Solid Works SimulationIJMER
This paper aims to do modelling, simulation and performing the static analysis of a go
kart chassis consisting of Circular beams. Modelling, simulations and analysis are performed using 3-D
modelling software i.e. Solid Works and ANSYS according to the rulebook provided by Indian Society of
New Era Engineers (ISNEE) for National Go Kart Championship (NGKC-14).The maximum deflection is
determined by performing static analysis. Computed results are then compared to analytical calculation,
where it is found that the location of maximum deflection agrees well with theoretical approximation but
varies on magnitude aspect.
In récent year various vehicle introduced in market but due to limitation in
carbon émission and BS Séries limitd speed availability vehicle in the market and causing of
environnent pollution over few year There is need to decrease dependancy on fuel vehicle.
bicycle is to be modified for optional in the future To implement new technique using change in
pedal assembly and variable speed gearbox such as planetary gear optimise speed of vehicle
with variable speed ratio.To increase the efficiency of bicycle for confortable drive and to
reduce torque appli éd on bicycle. we introduced epicyclic gear box in which transmission done
throgh Chain Drive (i.e. Sprocket )to rear wheel with help of Epicyclical gear Box to give
number of différent Speed during driving.To reduce torque requirent in the cycle with change in
the pedal mechanism
Integration of Struts & Spring & Hibernate for Enterprise ApplicationsIJMER
The proposal of this paper is to present Spring Framework which is widely used in
developing enterprise applications. Considering the current state where applications are developed using
the EJB model, Spring Framework assert that ordinary java beans(POJO) can be utilize with minimal
modifications. This modular framework can be used to develop the application faster and can reduce
complexity. This paper will highlight the design overview of Spring Framework along with its features that
have made the framework useful. The integration of multiple frameworks for an E-commerce system has
also been addressed in this paper. This paper also proposes structure for a website based on integration of
Spring, Hibernate and Struts Framework.
Microcontroller Based Automatic Sprinkler Irrigation SystemIJMER
Microcontroller based Automatic Sprinkler System is a new concept of using
intelligence power of embedded technology in the sprinkler irrigation work. Designed system replaces
the conventional manual work involved in sprinkler irrigation to automatic process. Using this system a
farmer is protected against adverse inhuman weather conditions, tedious work of changing over of
sprinkler water pipe lines & risk of accident due to high pressure in the water pipe line. Overall
sprinkler irrigation work is transformed in to a comfortableautomatic work. This system provides
flexibility & accuracy in respect of time set for the operation of a sprinkler water pipe lines. In present
work the author has designed and developed an automatic sprinkler irrigation system which is
controlled and monitored by a microcontroller interfaced with solenoid valves.
On some locally closed sets and spaces in Ideal Topological SpacesIJMER
In this paper we introduce and characterize some new generalized locally closed sets
known as
δ
ˆ
s-locally closed sets and spaces are known as
δ
ˆ
s-normal space and
δ
ˆ
s-connected space and
discussed some of their properties
Intrusion Detection and Forensics based on decision tree and Association rule...IJMER
This paper present an approach based on the combination of, two techniques using
decision tree and Association rule mining for Probe attack detection. This approach proves to be
better than the traditional approach of generating rules for fuzzy expert system by clustering methods.
Association rule mining for selecting the best attributes together and decision tree for identifying the
best parameters together to create the rules for fuzzy expert system. After that rules for fuzzy expert
system are generated using association rule mining and decision trees. Decision trees is generated for
dataset and to find the basic parameters for creating the membership functions of fuzzy inference
system. Membership functions are generated for the probe attack. Based on these rules we have
created the fuzzy inference system that is used as an input to neuro-fuzzy system. Fuzzy inference
system is loaded to neuro-fuzzy toolbox as an input and the final ANFIS structure is generated for
outcome of neuro-fuzzy approach. The experiments and evaluations of the proposed method were
done with NSL-KDD intrusion detection dataset. As the experimental results, the proposed approach
based on the combination of, two techniques using decision tree and Association rule mining
efficiently detected probe attacks. Experimental results shows better results for detecting intrusions as
compared to others existing methods
Natural Language Ambiguity and its Effect on Machine LearningIJMER
"Natural language processing" here refers to the use and ability of systems to process
sentences in a natural language such as English, rather than in a specialized artificial computer
language such as C++. The systems of real interest here are digital computers of the type we think of as
personal computers and mainframes. Of course humans can process natural languages, but for us the
question is whether digital computers can or ever will process natural languages. We have tried to
explore in depth and break down the types of ambiguities persistent throughout the natural languages
and provide an answer to the question “How it affects the machine translation process and thereby
machine learning as whole?” .
Today in era of software industry there is no perfect software framework available for
analysis and software development. Currently there are enormous number of software development
process exists which can be implemented to stabilize the process of developing a software system. But no
perfect system is recognized till yet which can help software developers for opting of best software
development process. This paper present the framework of skillful system combined with Likert scale. With
the help of Likert scale we define a rule based model and delegate some mass score to every process and
develop one tool name as MuxSet which will help the software developers to select an appropriate
development process that may enhance the probability of system success.
Material Parameter and Effect of Thermal Load on Functionally Graded CylindersIJMER
The present study investigates the creep in a thick-walled composite cylinders made
up of aluminum/aluminum alloy matrix and reinforced with silicon carbide particles. The distribution
of SiCp is assumed to be either uniform or decreasing linearly from the inner to the outer radius of
the cylinder. The creep behavior of the cylinder has been described by threshold stress based creep
law with a stress exponent of 5. The composite cylinders are subjected to internal pressure which is
applied gradually and steady state condition of stress is assumed. The creep parameters required to
be used in creep law, are extracted by conducting regression analysis on the available experimental
results. The mathematical models have been developed to describe steady state creep in the composite
cylinder by using von-Mises criterion. Regression analysis is used to obtain the creep parameters
required in the study. The basic equilibrium equation of the cylinder and other constitutive equations
have been solved to obtain creep stresses in the cylinder. The effect of varying particle size, particle
content and temperature on the stresses in the composite cylinder has been analyzed. The study
revealed that the stress distributions in the cylinder do not vary significantly for various combinations
of particle size, particle content and operating temperature except for slight variation observed for
varying particle content. Functionally Graded Materials (FGMs) emerged and led to the development
of superior heat resistant materials.
Energy Audit is the systematic process for finding out the energy conservation
opportunities in industrial processes. The project carried out studies on various energy conservation
measures application in areas like lighting, motors, compressors, transformer, ventilation system etc.
In this investigation, studied the technical aspects of the various measures along with its cost benefit
analysis.
Investigation found that major areas of energy conservation are-
1. Energy efficient lighting schemes.
2. Use of electronic ballast instead of copper ballast.
3. Use of wind ventilators for ventilation.
4. Use of VFD for compressor.
5. Transparent roofing sheets to reduce energy consumption.
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Optical and Impedance Spectroscopy Study of ZnS Nanoparticles
1. International Journal of Modern Engineering Research (IJMER)
www.ijmer.com Vol.3, Issue.4, Jul - Aug. 2013 pp-1857-1860 ISSN: 2249-6645
www.ijmer.com 1263 | Page
Ramna Tripathi1
& Akhilesh Kumar2
1
Department of Physics, THDC-Institute of Hydropower Engineering & Technology, Tehri, Uttarakhand, India
2
Department of Physics, Government Post Graduate College, Rishikesh, Uttarakhand, India
Abstract: Zinc Sulphide particle in the nanometer size regime has been synthesized using chemical routes. The particles
were capped using 2-mercaptoethanol to achieve the stability and avoid the coalescence. The as-obtained particles were
characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), UV–VIS absorption and
photoluminescence (PL) spectra. The dielectric measurements of the ceramic were carried out as a function of frequency
(100 Hz–1 MHz) and temperature (298–373 K) by impedance spectroscopy. Impedance spectroscopy was employed to
determine the electrical parameters (resistance, capacitance and relaxation time) of the grain and the grain boundary. The
grain boundary conduction, total grain (grain plus grain boundary) and the frequency max of grain boundary followed an
Arrhenius law associated with activation energies of 0.27eV, 0.28 eV and 0.3 eV respectively.
Keywords- Chemical synthesis, Impedance spectroscopy, Optical properties, Zinc Sulphide
I. INTRODUCTION
Zinc Sulphide is a semi-conducting material, with a wide band gap of 3.70 eV [1]. Among the wide band gap
materials, luminescent semi-conducting nanocrystals, also termed as nanophosphors, have been paid much attention
particularly for their life time shortening and enhanced emission efficiencies [2, 3]. There have been extensive reports in the
past few years demonstrating the systematic exploration of growing ZnS nanoparticles in the surfactant system to control the
particle size. Tang et al. [4] for example have studied the luminescence and photo physical properties of ZnS nanoparticles
prepared by reverse micelle method. During the recent years, various properties of ZnS have been investigated by
researchers [5-10].
It is to be mentioned that the impedance spectroscopy is one of the powerful tools for the characterization of
electrical properties of semiconducting nanomaterials. AC impedance spectroscopy allows measurement of the capacitance
and loss tangent (tan δ) and/or conductance over a frequency range at various temperatures. From the measured capacitance
and tan δ, four complex dielectric functions can be computed: impedance (Z*), electric modulus (M*), permittivity (ε*), and
admittance (Y*).
II. EXPERIMENTS
Although various methods are available for the synthesis of ZnS nanoparticles, chemical precipitation is widely
being used for the preparation of colloidal nanoparticles as the possibility of cluster formation is very less in this method
when compared to the other methods. Here, 0.27 g of ZnCl2 (1/10 M, 20ml) solution and 0.1M Na2S solution were prepared
in distilled water and were first refluxed for an hour separately. 50 ml Na2S solution was then added to the mercaptoethanol
solution of 0.25 ml (10-2
M) and then 20 ml ZnCl2, which was continuously refluxed to get a colloidal form of ZnS. The
colloidal sample was refluxed for another 20 min at 80°C for uniform distribution of the particles. Then this was filtered out
and washed with distilled water and ethanol for removing the additional impurities formed during the preparation process.
The filtrate was dried at room temperature, which yields high-quality ZnS nanocrystals.
The X-ray diffraction of the sample at room temperature is taken by a powder X-ray diffratometer (Rigaku
Miniflex-II). The transmission electron micrograph of the sample is taken by a transmission electron microscope (Jeol JEM-
100cx). The absorption and luminescence spectra for ZnS nanoparticles were recorded using UV-Visible spectrophotometer
(Shimadzu UV-2450) and spectrofluorometer (Shimadzu RF-5310) respectively.
The dielectric measurement of the sample of thickness 2.06 mm and diameter 10.41 mm was carried out using gold
electrodes by an LCR meter (Hioki) in the frequency range from 100 Hz to 1 MHz and in the temperature range from 298 K
to 373 K. The temperature was controlled with a programmable oven. All the dielectric data were collected while heating at
a rate of 10
C min-1
. The complex electric modulus M*
(=1/ε*
) and impedance Z*
(=M*
/jωCo) are obtained from the
temperature dependence of the real (ε') and imaginary (ε") components of the dielectric permittivity ε*
(= ε'-jε") and ε"= ε'
tan δ.
III. RESULTS AND DISCUSSION
Fig. 1 shows the X-ray diffraction pattern of the sample taken at room temperature. The broadening of the
diffraction peaks is primarily due to the finite size of the nanocrystallites and is quantitatively analyzed by the Debye–
Scherrer formula
cos
94.0
B
L (1)
Optical and Impedance Spectroscopy Study of ZnS
Nanoparticles
2. International Journal of Modern Engineering Research (IJMER)
www.ijmer.com Vol.3, Issue.4, Jul - Aug. 2013 pp-1857-1860 ISSN: 2249-6645
www.ijmer.com 1263 | Page
where L is the average size of the particle, λ is the wavelength of X-ray radiation, B is the full width at half maximum
(FWHM) and θ is the diffraction angle. According to the data in Fig. 1 and given formula, the average particle size of the
material is found to be 45 nm. The transmission electron micrograph of the ZnS is shown in the inset of Fig. 1. The average
grain size of the nanoclusters of ZnS is found to be 50 nm. Particle size analyzed by XRD and TEM are in good agreement.
Fig. 1. The XRD (TEM micrograph shown in the inset) for ZnS.
The inset of Fig. 2 shows the UV – visible spectra of ZnS nanoparticles in the absorbance range of 200-350 nm. The
absorbance peak at 277 nm is blue shifted compared to the bulk ZnS for which absorption peak is at 345 nm. The blue-
shifted absorption edge is due to the quantum confinement of the excitons present in the sample, resulting in a more discrete
energy spectrum of the individual nanoparticles. The broadening of the absorption spectrum is mainly due to the quantum
confinement of the ZnS nanoparticles. The effect of the quantum confinement on impurity critically depends on the size of
the host crystal. As the host decreases, the degree of confinement and its effect increases. The band gap energy is increased
(~4.1 eV) compared to that (~3.6 eV) of bulk ZnS shown in the Fig. 2, the enlargement of the band gap can be attributed to
the quantum confinement effect of the ZnS nanoparticles.
Fig. 2. Energy band gap determination of ZnS nanoparticles. The UV-visible absorption spectra of the ZnS
nanoparticles shown in the inset.
Fig. 3 shows the PL emission (a) and excitation (b) spectra of ZnS nanoparticles. It shows strong blue-luminescence with
peak maximum around 335 nm and a side band at 352 nm. The corresponding excitation spectra with peak maximum at 420
nm indicate energy-transfer from the band-to-band electronic excitation of the quantum confined ZnS [11].
Fig.3. Photoluminescence emission spectra of ZnS nanoparticles.
With the self-aggregation of nanoparticles, the excitation spectra also show reduction in the intensity but more significantly,
a gradual red-shift in the peak maximum with larger line broadening. The origin of the blue-luminescence of ZnS
nanoparticles has been studied by different groups [11, 12]. Highly asymmetric and broadened emission band with multiple
3. International Journal of Modern Engineering Research (IJMER)
www.ijmer.com Vol.3, Issue.4, Jul - Aug. 2013 pp-1857-1860 ISSN: 2249-6645
www.ijmer.com 1263 | Page
peak maxima indicate the involvement of different luminescence centers in the radiative process. The nanoparticles prepared
under sulphur deficient synthetic condition of S2-
/Zn2+
will have larger concentration of sulphur vacancies (VS).
Fig.3. Photoluminescence excitation spectra of ZnS nanoparticles.
It is reported that sulphur vacancies can act as doubly ionized electron trap centers and facilitate VS/VB (valence band)
and/or VS/SS (surface states, including interstitial defects and impurities) [11]. Though the lattice vacancies are point
defects, due to the large surface-to-volume ratio of nanoparticles, the concentration of these defects will be more at the
surface regions than the interiors. Therefore, in the ZnS nanoparticles with unmodified surfaces, the effect of surface states
will be dominant as seen by the strong blue luminescence. However, the observed quenching of these emission bands with
the self-assembly of nanoparticles suggests that the vacancy centers are annihilated during the particle-to-particle
attachment/interface precipitation by way of incorporation of more and more crystal growth units at the nanoparticles
surfaces.
Fig. 4 shows a complex-plane impedance plot (Z*) of ZnS, plotting the imaginary part Z" against the real part Z'. In general,
for a perfect crystal, the values of resistance R and capacitance C can be analyzed by an equivalent circuit of one parallel
resistance-capacitance (RC) element. This RC element give rise to one semicircular arc on the complex plane and has
intercepts on the Z' axis of zero and R. Thus, C can be calculated with the relation ωmRC=1, where ωm=2πνm and νm is the
frequency at the arc maxima.
Fig.4. The complex–plane impedance plot with the corresponding equivalent circuit is shown for ZnS at various
temperatures. The solid line is the best fit for ZnS. The inset shows expanded views of the high-frequency data near
the origin at 323 K.
For a nano crystal containing interfacial boundary layers, the equivalent circuit may be considered as two parallel RC
elements connected in serial and giving rise to two arcs in complex plane: one for the nano crystal (grain) and the other for
the interfacial boundary (grain-boundary) response. The relative position of the two arcs in the complex plane can be
identified by the frequency. Based on the equivalent circuit consisting of two parallel RC elements in series, the nonzero
intercept on the Z'-axis (at 323 K) indicates the presence of an arc with ωmax higher than the maximum frequency measured
(1 MHz).
Dielectric relaxation observed in electroceramics are better analysed using the simplified equivalent circuits
consisting of two parallel RC circuits connected in series, one RC element, Rg Cg, representing the grain, and the other
RgbCgb, representing the grain boundary [13, 14], as shown in the inset of Fig. 4. Here, Rg, Cg and Rgb, Cgb are the resistance
and capacitance associated with the grain and the grain boundary, respectively. Each parallel RC element results in a
semicircle in the impedance plots. Fig. 4 shows a complex impedance Z* (Z" versus Z') plot for ZnS nanoceramics, obtained
by plotting the imaginary part (Z") against the real part (Z') in the 323 K–363 K temperature range. The high frequency
impedance response of the sample in the 323 K–363 K temperature range has been highlighted in Fig. 5 to show the
evolution of the high frequency semicircle.
4. International Journal of Modern Engineering Research (IJMER)
www.ijmer.com Vol.3, Issue.4, Jul - Aug. 2013 pp-1857-1860 ISSN: 2249-6645
www.ijmer.com 1263 | Page
Fig.5. Arrhenius plot for the grain boundary resistance (Rgb) and total grain. The insetshows grain boundary
relaxation frequency (ωgb) for ZnS nanoceramics. The solid line is the best fit for the Arrhenius equations.
The equivalent electrical equation can be represented by
22
1)(1
'
gbgb
gb
gg
g
CR
R
CR
R
Z
(2)
22
11
"
gbgb
gbgb
gb
gg
gg
g
CR
CR
R
CR
CR
RZ
(3)
The best fitting of RC equivalent circuit by solid line for 323 K, 343 K and 363 K with two semicircular arc of Rg and Rgb is
shown in the table 1.
The resistance values of the grains and the grain boundaries are obtained from the intercepts of the corresponding
semicircles with the real axis (Z') (diameter of each semicircle) which gives Rg and Rgb, respectively. The resistance obtained
for the total resistance or dc resistance of the sample log (Rg + Rgb) and log Rgb is plotted in the Arrhenius format in the Fig.
5, obey the Arrhenius law with activation energy of 0.28 eV and 0.27 eV respectively. Plot of log (ωgb) (relaxation frequency
of grain boundary) (inset of Fig. 5) reveal that ωgb follow an Arrhenius law associated with activation energies of 0.28 eV.
Furthermore, as it is clear from Fig. 5, Rgb + Rg are only slightly higher than Rgb in the entire temperature range under study.
Hence, it could be concluded that Rgb >> Rg, so that in the entire temperature range Cgb >> Cg.
IV. CONCLUSIONS
The frequency-dependent dielectric dispersion of ZnS nanoparticles synthesized by soft chemical method is
investigated in the temperature range from 298 K to 373 K for the first time. The increasing dielectric constant with
increasing temperature is attributed to the conductivity which is directly related to an increase in mobility of localized charge
carriers. Analyses of the real and imaginary part of complex permittivity with frequency were performed assuming a
distribution of relaxation times as confirmed by Cole-Cole plot as well as the scaling behavior of impedance spectra. The
scaling behavior of the imaginary part of impedance spectra suggests that the relaxation describes the same mechanism at
various temperatures. The frequency-dependent electrical data are also analyzed in the framework of conductivity and
modulus formalisms.
ACKNOWLEDGMENT
R. Tripathi and A. Kumar are thankful to Uttarakhand state council of science and technology (U-COST) for its
financial support, SAIF, Bose Institute, Kolkata for instrument facility and Gajendra Saini, AIRF, Jawaharlal Nehru
University (JNU), New Delhi for TEM measurement.
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