ABSTRACT : Graphene features higher thermal conductivity than copper. However, despite its superior property, the research on its applicable technology was limited since the van der Waals’ forces between graphene. As a solution to such problem, research on making graphene distributed evenly in solvent is being actively conducted via physical and chemical method. Because the chemical method is likely to have harmful effect on the environment, we used the environmental-friendly process that does not consume toxic chemicals, and suitable for application. In this study, ball milling process controllable a range of experiment conditions more easily and conveniently than other physical methods was conducted so as to disperse graphene evenly in solvent and improve the thermal conductivity. Therefore, the effect of milling process was confirmed in TEM image and Raman ratio, and the shearing force makes the edge of graphene piece defective. When graphene is evenly dispersed, the wide specific surface area absorbs a great deal of light, improving absorbance. We confirmed the absorbance of pristine graphene was showed below milling graphene and considerable thermal conductivity increase compared to pristine graphene.
Keywords: Ball milling, Graphene, Nano-fluid, Physical process, Thermal conductivity
The reinforcing effects of graphene oxide (GO) on portland cement paste are investigated. It is dis- covered that the introduction of 0.05% by weight GO sheets into the cement paste can increase the compressive strength and tensile strength Of the cement composite due to the reduction of the pore structure of the cement paste.The overall results indicate that GO reinforcing the engineering properties of portland cement.
In this experimental study, the reinforcing effects of graphene oxide (GO) on portland cement paste are investigated. It is dis- covered that the introduction of 0.05% by weight GO sheets into the cement paste can increase the compressive strength and tensile strength Of the cement composite due to the reduction of the pore structure of the cement paste.The inclusion of the GO Sheets enhances the degree of hydration of the cement paste. However, the workability of the GO-cement composite becomes somewhat Reduced. The overall results indicate that GO reinforcing the engineering properties of portland cement.
ROOF TILE POWDER AS A PARTIAL REPLACEMENT TO CEMENT IN MASONRY MORTARcivej
Ordinary Portland cement is an inevitable material for construction. However, it is highly energy intensive
and liable for the emission of green house gases. In this context, utilization of pozzolanic materials as
supplementary cementing materials has become the leading research interest in recent decades. Roof tile
industries generate huge amount of solid waste materials during their manufacturing processes. Disposal
of these waste materials is serious environmental concern. This paper presents the results of the study
conducted on the potential of roof tile powder (RTP) as a cement replacement material in mortar. The
physical, chemical and mineralogical compositions of RTP were investigated. Strength characteristics of
masonry mortar with varying proportions of RTP as cement replacement were tested. The test results verify
the potential of roof tile powder as partial replacement to cement in masonry mortar upto an extend of 15-
20% in 1:3 and 1:5 mortar proportions respectively.
Effect Of Curing Temperature And Curing Hours On The Properties Of Geo-Polyme...ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
The reinforcing effects of graphene oxide (GO) on portland cement paste are investigated. It is dis- covered that the introduction of 0.05% by weight GO sheets into the cement paste can increase the compressive strength and tensile strength Of the cement composite due to the reduction of the pore structure of the cement paste.The overall results indicate that GO reinforcing the engineering properties of portland cement.
In this experimental study, the reinforcing effects of graphene oxide (GO) on portland cement paste are investigated. It is dis- covered that the introduction of 0.05% by weight GO sheets into the cement paste can increase the compressive strength and tensile strength Of the cement composite due to the reduction of the pore structure of the cement paste.The inclusion of the GO Sheets enhances the degree of hydration of the cement paste. However, the workability of the GO-cement composite becomes somewhat Reduced. The overall results indicate that GO reinforcing the engineering properties of portland cement.
ROOF TILE POWDER AS A PARTIAL REPLACEMENT TO CEMENT IN MASONRY MORTARcivej
Ordinary Portland cement is an inevitable material for construction. However, it is highly energy intensive
and liable for the emission of green house gases. In this context, utilization of pozzolanic materials as
supplementary cementing materials has become the leading research interest in recent decades. Roof tile
industries generate huge amount of solid waste materials during their manufacturing processes. Disposal
of these waste materials is serious environmental concern. This paper presents the results of the study
conducted on the potential of roof tile powder (RTP) as a cement replacement material in mortar. The
physical, chemical and mineralogical compositions of RTP were investigated. Strength characteristics of
masonry mortar with varying proportions of RTP as cement replacement were tested. The test results verify
the potential of roof tile powder as partial replacement to cement in masonry mortar upto an extend of 15-
20% in 1:3 and 1:5 mortar proportions respectively.
Effect Of Curing Temperature And Curing Hours On The Properties Of Geo-Polyme...ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
Ordinary Portland Cement (OPC) production produces
substantial CO2 emission. Geopolymer Concrete (GPC)
will be of considerable cure to Global Warming related
with construction industry since GPC replaces OPC
completely or about 80% with industrial waste products. In
this study GPC was made up of Ground Granulated Blast
furnace Slag (GGBS) and Red Mud (RM) incorporating
hybrid fibres in various ratios. Results show that, among
all the mixes, one mix showed the best mechanical
properties owing to the incorporation of hybrid fibres
and reduction of Red Mud.
International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
Effect of activator solution on compressive strength of flyash geopolymer ble...IJERA Editor
The influence of the composition of activator solution on the strength of fly ash geopolymer blended with slag was investigated. The research variable include % Na2O and sodium silicate under typical controlled parameters like curing profile, water content, base material and supplementary material. In this study, the monitoring response variable was compressive strength. Finding suggests that activator solution combination has a significant effect on the properties of the GP (non-blended geopolymer) and GB (geopolymer blended with 15% slag). The experiment concludes that higher percentage of Na2O gives lower strength for GB specimens but corresponding higher strength for GP specimens. Silicate modulus has similar impact on GP and GB. Both for GP and GB specimens compressive strength is increase with higher silicate modulus.
The Journal of MC Square Scientific Research is published by MC Square Publication on the monthly basis. It aims to publish original research papers devoted to wide areas in various disciplines of science and engineering and their applications in industry. This journal is basically devoted to interdisciplinary research in Science, Engineering and Technology, which can improve the technology being used in industry. The real-life problems involve multi-disciplinary knowledge, and thus strong inter-disciplinary approach is the need of the research.
In manufacturing, many products need to undergo increasing customisation, and a shortening of the manufacturing cycle time. This makes the time needed to produce prototypes one of the most important contributors to product development cycles. Rapid Prototyping (RP) offers the user the ability to optimise part design in order to meet customer requirements with few manufacturing restrictions. One of the most common RP processes is Laser Sintering (LS). A problem with LS is that sometimes the surface of the parts produced displays a texture similar to that of the skin of an orange (the so-called orange peel texture). This problem must be addressed before the technology can gain wider acceptance. The main aim of this research is to develop a methodology of controlling the input material properties that will ensure consistent and good quality of the fabricated parts. From the experiment, it was found that PA12 powder with high melt flow rate, low melting temperature, low glass transition temperature and low degree of crystallization temperature could improve the sintering process to produce a good Laser Sintering (LS) parts with lower shrinkage rate. The powder which has higher melt viscosity and lower melting heat becomes liquid more easily and therefore flows better during the sintering process due to a shorter chain molecular structure. The results of experimental work indicate that the melt viscosity, and part surface finish are correlated.
Ordinary Portland Cement (OPC) production produces
substantial CO2 emission. Geopolymer Concrete (GPC)
will be of considerable cure to Global Warming related
with construction industry since GPC replaces OPC
completely or about 80% with industrial waste products. In
this study GPC was made up of Ground Granulated Blast
furnace Slag (GGBS) and Red Mud (RM) incorporating
hybrid fibres in various ratios. Results show that, among
all the mixes, one mix showed the best mechanical
properties owing to the incorporation of hybrid fibres
and reduction of Red Mud.
International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
Effect of activator solution on compressive strength of flyash geopolymer ble...IJERA Editor
The influence of the composition of activator solution on the strength of fly ash geopolymer blended with slag was investigated. The research variable include % Na2O and sodium silicate under typical controlled parameters like curing profile, water content, base material and supplementary material. In this study, the monitoring response variable was compressive strength. Finding suggests that activator solution combination has a significant effect on the properties of the GP (non-blended geopolymer) and GB (geopolymer blended with 15% slag). The experiment concludes that higher percentage of Na2O gives lower strength for GB specimens but corresponding higher strength for GP specimens. Silicate modulus has similar impact on GP and GB. Both for GP and GB specimens compressive strength is increase with higher silicate modulus.
The Journal of MC Square Scientific Research is published by MC Square Publication on the monthly basis. It aims to publish original research papers devoted to wide areas in various disciplines of science and engineering and their applications in industry. This journal is basically devoted to interdisciplinary research in Science, Engineering and Technology, which can improve the technology being used in industry. The real-life problems involve multi-disciplinary knowledge, and thus strong inter-disciplinary approach is the need of the research.
In manufacturing, many products need to undergo increasing customisation, and a shortening of the manufacturing cycle time. This makes the time needed to produce prototypes one of the most important contributors to product development cycles. Rapid Prototyping (RP) offers the user the ability to optimise part design in order to meet customer requirements with few manufacturing restrictions. One of the most common RP processes is Laser Sintering (LS). A problem with LS is that sometimes the surface of the parts produced displays a texture similar to that of the skin of an orange (the so-called orange peel texture). This problem must be addressed before the technology can gain wider acceptance. The main aim of this research is to develop a methodology of controlling the input material properties that will ensure consistent and good quality of the fabricated parts. From the experiment, it was found that PA12 powder with high melt flow rate, low melting temperature, low glass transition temperature and low degree of crystallization temperature could improve the sintering process to produce a good Laser Sintering (LS) parts with lower shrinkage rate. The powder which has higher melt viscosity and lower melting heat becomes liquid more easily and therefore flows better during the sintering process due to a shorter chain molecular structure. The results of experimental work indicate that the melt viscosity, and part surface finish are correlated.
Graphene: the world's first 2D material. Since graphene's isolation in 2004, it has captured the attention of scientists, researchers, and industry worldwide.
Synthesis of Graghene, with characterization and application.Hamza Suharwardi
graphene has huge effects on the environment so I synthesize this and perform the XRD, FTIR and simulate On Blender, moreover, I presented the implementation in several fields.
Progress in Synthesis of Graphene using CVD, Its Characterization and Challen...paperpublications3
Abstract: Diamond and Graphite both are natural allotropes of carbon. Graphene is a substance composed of sp2 hybridized carbon atoms that are similar to graphite and arranged in a regular hexagonal pattern. Graphene has astounding physical properties such as high electronic conductivity, excellent mechanical strength and thermal stability. It is capable to maintain its strength up to 3,600°C. It is transparent, high super hydrophobicity at nanometer scale , 100 times stronger than steel with high current density. These unique properties make graphene an interesting candidate for a number of applications currently under development, as for instance Li-ion batteries, transparent touch screens, light weight aircrafts or transistors.
Amongst the synthesis techniques, chemical vapor deposition has proved promising result for advance devices and for numerous applications where high-quality graphene films, High purity, fined grained and low structural defects film is required. CVD process is normally conducted below the atmospheric pressure and relatively lower temperatures , less than 1000°C. Pressure of LPCVD is 10-1000 Pascals.
Keywords: CVD, Graphene, Graphite, Graphene sheets..
Title: Progress in Synthesis of Graphene using CVD, Its Characterization and Challenges: A Review
Author: Sakshi Rana, Harminder Singh
International Journal of Recent Research in Electrical and Electronics Engineering (IJRREEE)
ISSN 2349-7815
Paper Publications
Solar power is looking more and more attractive, as other power generation
methods such as fossil fuels and nuclear power come under increasing scrutiny
Nano material solar cells shows special promise to both enhance efficiency of
solar energy conservation and also reduce the manufacturing cost
It increase efficiently by the absorption of light as well as the overall radiation
to electricity would help preserve the environment, decrease wastage, provide
electricity for rural areas, and have a wide array of commercial applications
due to its capabilities
The effect of functionalized carbon nanotubes on thermalmechanical performanc...journal ijrtem
The new approaches for preparing nanocomposite coating by modificated carbon nanonotubes
(CNTs) and epoxy resin was done in the study. thermal-mechanical performance of nanocomposite coating was
investigated and the results were reported in this paper. The physic-chemical techniques such as Differential
scanning calorimetry (DSC) and Thermal gravimetric analysis (TGA) were used to characterize the thermal
performance of Epoxy nanocomposite coating. The test techniques for mechanical properties of paint coating as
adhesion, hardness, impact resistance and bending strength were employed in the work. The results indicated
that CNTs were dispersed in epoxy coating with only ratio of 0.1 wt% enhanced the Glass Transition
Temperature (Tg), decomposition temperature of epoxy coating and improved mechanical properties
significantly. Also functionalized CNTs can be reinforced thermal-mechanical of the epoxy coating better than
neat CNTs.
Development Issues and Problems of Selected Agency in Sorsogon, An investigat...journal ijrtem
: The study venture on the developing issues and problems of selected agency in the province of
Sorsogon with an end-view of identifying solution towards achieving effective delivery of services to the
public. The agencies covered by the study are the employers of the students enrolled in Public Administration
512 subject in the graduate school program of the Sorsogon State College 1st semester SY 2016. Guided by a
structured matrix questionnaire and checklist, the class spearheaded by the assigned focal person per
identified respondent-agency conducted a focus group discussion covering sequentially the issues and
problems besetting the organization. It likewise pursued how does it affects the management & performance of
the office and ultimately identifying possible solutions out of the issues and problems. Result revealed that
most pressing problems and issues of the selected agency in the province of Sorsogon covers; (a) understaffed,
(b) poor communication, (c) poor implementation of the policy, and (d) poor performance feedback
mechanism in the system
Positive and negative solutions of a boundary value problem for a fractional ...journal ijrtem
: In this work, we study a boundary value problem for a fractional
q, -difference equation. By
using the monotone iterative technique and lower-upper solution method, we get the existence of positive or
negative solutions under the nonlinear term is local continuity and local monotonicity. The results show that we
can construct two iterative sequences for approximating the solutions
Organic foods refer to products that are grown naturally or produced by methods that comply
with the standards of organic farming. They are not only environmentally friendly, they are also healthy. Many
people believe organic foods are healthier than conventional food. Today, organic foods have become very
popular and everyone wants to know about their benefits. This paper provides a brief introduction on organic
foods and their pros and cons.
Molecular computers are systems in which molecules or macromolecules individually mediate
information processing functions. Molecular computing provides an alternative to computing using silicon
integrated circuits. It aims at developing intelligent computers using biological molecules as computational
devices. It is a promising means of unconventional computation owing to its capability for massive parallelism.
It offers to augment digital computing with biology-like capabilities. This paper provides a brief introduction to
molecular computing.
Industry 4.0 refers to the current trend of automation and deployment of Internet technologies
in manufacturing. This includes using machine-to-machine and Internet of Things (IoT) deployments to help
manufacturers implement increased automation, improved communication and process monitoring. This trend
of Industry 4.0 (sometimes referred to as the 4th Industrial Revolution) affects most processes and people
throughout society. This paper provides a brief introduction to Industry 4.0.
With mounting concerns over the state of our planet, there is continuing demand that chemists
and chemical engineers should develop greener chemical processes and products. In the 1990s, with the
growing awareness of the hazardous impacts of the chemical industry, the green chemistry revolution was
launched by American chemists Paul T. Anastas and John Warner. Green chemistry is the kind of chemistry that
seeks to minimize pollution, conserve energy, and promote environmentally friendly production. This paper
provides a brief introduction to green chemistry
Rural Livelihood and Food Security: Insights from Srilanka Tapu of Sunsari Di...journal ijrtem
Food security is the foremost need of every human society. It is a fundamental right and
government responsibility but still food insecurity is prevalent in rural areas of least developed nations. To cope
with food insecurity, undertaking diverse income generating activities is common as well as key strategy adopted
by rural people. The objective of this study is to assess rural livelihood and food security status of a remote island
named Srilanka Tapu of Sunsari district. A random sampling technique was used to collect primary data from 40
rural household heads using semi-structured questionnaire. Descriptive methods were used for analyzing. The
findings revealed that the food security situation of the Tapu is insecure. Most basic infrastructures and social
services needed for people livelihood such as road, electricity sufficient food availability, education, healthcare,
sanitation, etc. were found to be extremely poor. Most of the households are small scale farmers involving
themselves in diverse livelihood activities which are mostly temporary, low-skilled and low paying. However,
people are fulfilling their food needs at every cost but are highly vulnerable to food insecurity. Also, their lives
security is equally vulnerable because of disastrous Koshi River flooding which occurs every year in the Tapu.
The findings therefore critically suggest that food security of remote and vulnerable human settlements should be
at top priority in policy formulation and implementation level. The study also recommends a need for an in-depth
research for making evidence based policy interventions for improvement of diversify rural livelihood along with
sustainable environment
Augmented Tourism: Definitions and Design Principlesjournal ijrtem
After designing and implementing several iterations of implantations of augmented reality(AR) in
tourism, this paper takes a deep look into design principles and implementation strategies of using AR at
destination tourism settings. The study looks to define augmented tourism from past implementations as well as
several cases uses designed and implemented for tourism. The discussion leads to formation of frameworks and
best practices for AR as well as virtual reality(VR) to be used in tourism settings. Some main affordances include
guest autonomy, customized experiences, visitor data collection and increased electronic word-of-mouth
generation for promotion purposes. Some challenges found include the need for high levels of technology
infrastructure, low adoption rates or ‘buy-in’ rates, high levels of calibration and customization, and the need for
maintenance and support services. Some suggestions are given as to how to leverage the affordances and meet
the challenges to implementing AR for tourism
A study on financial aspect of supply chain management journal ijrtem
The more common approaches used in the SCM consider only the physical logistic operations
and ignore the financial aspects of the supply chain. The main objective to incorporate financial aspects in
supply chain management is to strengthen managerial decisions concerning financial flows in supply chains,
while empirical knowledge about financial supply chain management (FSCM) is in its early stages. This paper
presents a model for FSCM which financial planning in addition to operation planning is decided in it. The
main contribution of this paper is to define two approaches for Financial Supply Chain Management and to
compare them. This financial approaches are: Traditional financial approach and new financial approach.
Traditional financial approach integrates physical goods flows and financial flows. New financial approach
considers in making decisions other financial indicators such as market to book value, liquidity ratios, capital
structure ratios, and return on equity, sales margin, turnover ratios and stock security ratios, among others.
Moreover, the new approach applies the change in equity instead of the traditional approach measures of profit
as the objective function to be maximized in the presented model. To show the attributes of the presented
approaches, the results of the new approach and the traditional approach is compared. The findings indicate
that the traditional approach leads to lower change in equity compared to the financial approach. Also, the
results clearly reveal the better improvement of using the new approach over the traditional approach, and
convince the decision makers to take advantage of the new approach
Existence results for fractional q-differential equations with integral and m...journal ijrtem
This paper concerns a new kind of fractional q-differential equation of arbitrary order by
combining a multi-point boundary condition with an integral boundary condition. By solving the equation which
is equivalent to the problem we are going to investigate, the Green’s functions are obtained. By defining a
continuous operator on a Banach space and taking advantage of the cone theory and some fixed-point theorems,
the existence of multiple positive solutions for the BVPs is proved based on some properties of Green’s functions
and under the circumstance that the continuous functions f satisfy certain hypothesis. Finally, examples are
provided to illustrate the results.
The following Project shows the benefits of a research established into a multi-products
warehouse belongs to an automotive industry supplier. The main goal was applied a tool recognizing the rules
for distribution and material storage. Once the research was completed, the benefits were, the idle times
reduction per hours/week by the two initial processes. The politics for storage assignment and location, propose
a system to improve the space into this areain order to avoid material management and flow issues. It is
important to mention, the system proposed could be applied into warehouses with storage size and space
restricted by sorting area, also different material types, production settings and physical specifications for
which set warehouses with traditional management of distribution without slack, involves lack of materials,
pieces without records, incorrect location assigned, stock error.
Study of desalination processes of seawater from the desalination plant of La...journal ijrtem
: The use of water for food purposes requires excellent physicochemical quality. To contribute to
the control of water quality. Water treated by reverse osmosis is aggressive and demineralize can not be used
directly as a source of drinking water. The objective of this work is to study, physics-chemical analyzes of raw
water, pretreated osmosis and treated (permeate) and produced water (reservoir) at the desalination plant of
seawater Laayoune (SDL), located in southern Morocco. For this, we have followed several qualitative
parameters such as pH, conductivity, turbidity.
Effect of Cash Management on The Financial Performance of Cooperative Banks i...journal ijrtem
This paper analyses the effect of cash management on the financial performance of cooperatives
banks in Rwanda. A descriptive research design was used. The population comprised of 148 employees of ZIGMA
CSS from which a sample of 108 employees was determined using Solvirn and Yemen’s formula. Data was
collected from both primary and secondary sources using questionnaires and document analysis. Data was
presented using frequency tables from which analysis was made. A multi regression analysis was used to analyse
relationship between the variables. The results from the survey revealed that ZIGMA CSS uses various cash
management techniques in the cash management. The results further revealed a strong relationship between cash
management and financial performance of ZIGMA CSS. The study concludes that cash management is a key tool
in the financial management of the banks since cash forms the biggest asset of the bank. Cooperatives banks
should ensure that they develop policies in effective cash management.
Technical expertise on the cause of engine failure of the Mitsubishi Pajero S...journal ijrtem
The article concerns the case of the damage to the Mitsubishi Pajero Sport engine and the
methodology a technical expert applied to identify a direct cause of failure. The engine failure occurred while a
vehicle was being repaired to eliminate air conditioning malfunction and engine overheating. When repairing, it
was necessary to replace a cylinder head and the pistons were checked removing the pully from a crank shaft.
After the repair had been completed and after 16-day vehicle operation, engine timing belts got damaged. To
eliminate this malfunction, damaged belts were replaced. Thirty (30) days after the vehicle had been put into
operation, emergency engine failure occurred, and a technical expert was called upon to assess the quality of the
repairs having been performed. The article describes the procedures and methodology a technical expert applied.
In the conclusion, the findings are stated. To determine the cause, a vehicle was on the car service station
premises, where a technical expert was present and according to his instructions, diagnostic and subsequent
disassembly works have been done. The procedure of evaluating the key characteristics on individual parts, their
display, and the resulting evaluation are described.
Clustering based Time Slot Assignment Protocol for Improving Performance in U...journal ijrtem
Recently, numerous approaches have been proposed for designing medium access control (MAC)
in underwater acoustic networks (UANs). Some of those works tried to adapt MAC protocols proposed for
terrestrial networks. However, unique environmental characteristics of UANs make the MAC protocols hard to be
used in the UANs and degrade network performance. In order to improve network performance, COD-TS MAC
protocol was proposed. COD-TS focuses on both single hop and multi-hop mode and utilizes CDMA for
exchanging schedule information between cluster heads. COD-TS has shortcomings such as collisions, additional
energy consumption by exchanging schedule information and near-far effect of CDMA. To overcome above
shortcomings, we propose a clustering-based time slot assignment protocol. In the proposed protocol, nodes are
clustered, and each cluster head performs two-hop neighbor cluster discovery operation. And then, a cluster head
obtains its own relative position information. Finally, the cluster head assigns its own time slot for data
transmission based on the information. Simulation results show that the proposed protocol has always better
performance compared to the COD-TS.
Design and Implementation of Smart Bell Notification System using IoT journal ijrtem
Smart phones have become part of our daily life. People using smart phones have increased
rapidly. The proposed paper is to provide a security system that combines the functions of smart phone and home
network system. It enables the users to check the image of the visitor who is present at the door. It also saves all
the images in their drive. We send an alert message to the Owner whenever the doorbell is pressed. Furthermore,
the owner can call to the visitor with the help of our app. We are also providing a link in the SMS sent so that it
redirects the user to the app
Assessment of the Water Quality of Lake Sidi Boughaba (Ramsar Site 1980) Keni...journal ijrtem
Sidi Boughaba Lake, part of a wetland complex of Morocco (Ramsar site in 1980) is located on
the Atlantic coast of northwestern Morocco, oriented NNE - SSW and located in an interdunal depression. The
existence of this body of water is due to the fact that the topographic surface is at a lower cost than that of the
piezometric surface of the coastal water table, rainwater and runoff water. The objective of this study is to
determine the physical and chemical characteristics of the waters of this lake. Thus, several water samples were
taken monthly in the period 2016-2017. Parameters such as: temperature, pH, electrical conductivity (EC),
chloride (Cl-
), turbidity (NTU), calcium (Ca2+) and magnesium (Mg2+). The results obtained show that the
distribution of the analyzed elements in Lake waters is quite variable between seasons, as well as between stations.
However, the analysis showed that the studied waters are very mineralized, with an EC between 7 g/l and 14.8
g/l. This mineralization is essentially evaporitic and is controlled by various processes, such as evaporation and
marine influence by aerosol.
The case of a cyclist and tractor traffic accident journal ijrtem
When assessing the cause of a traffic accident, it is also necessary for the technical expert to
take into account the real influences that affect individual participants. This is especially important for accidents
in which one of the participants is cyclist. Technical expert must consider all the circumstances necessary to
assess the cyclist´s behavior. Negligible is not even the age of a cyclist, since in the case of a child or an old man
the driver overtaking bicycle should take this into consideration. The article deals with case of traffic accident
between tractor with the trailer and a bicycle which was riding by cyclist at the age of 80. Apart from the described
procedure by expert in the calculations, the influences on participants' behavior are also discussed
: This paper is aimed at designing a density based dynamic traffic signal system where the timing
of signal will change automatically on sensing the traffic density at any junction using the IoT technology. Traffic
congestion is a severe problem in most cities across the world and therefore it is time to shift more manual mode
or fixed timer mode to an automated system with decision making capabilities. To optimize this problem, we have
made a framework for an intelligent traffic control system. Sometimes higher traffic density at one side of the
junction demands longer green time as compared to standard allotted time. We therefore propose here a
mechanism in which the time period of green light and red light is assigned on the basis of the density of the
traffic present at the time. This is achieved by using LIDAR sensors.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Vaccine management system project report documentation..pdfKamal Acharya
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Grinding graphene characteristics after physical process
1. Invention Journal of Research Technology in Engineering & Management (IJRTEM)
ISSN: 2455-3689
www.ijrtem.com Volume 1 Issue 12 ǁ September. 2017 ǁ PP 18-24
| Volume 1 | Issue 12 | www.ijrtem.com | 18 |
Grinding graphene characteristics after physical process
1,
Ji-Hye Kim , 2,
Gwi-Nam Kim , 3,
Jung-Pil Noh , 4,
HyoMin Jeong , 5,
Sun-Chul Huh
1,2,3,4,5,
(Department of Energy and Mechanical Engineering, Gyeongsang National University, Republic of Korea)
ABSTRACT : Graphene features higher thermal conductivity than copper. However, despite its superior property, the research on
its applicable technology was limited since the van der Waals’ forces between graphene. As a solution to such problem, research on
making graphene distributed evenly in solvent is being actively conducted via physical and chemical method. Because the chemical
method is likely to have harmful effect on the environment, we used the environmental-friendly process that does not consume toxic
chemicals, and suitable for application. In this study, ball milling process controllable a range of experiment conditions more easily
and conveniently than other physical methods was conducted so as to disperse graphene evenly in solvent and improve the thermal
conductivity. Therefore, the effect of milling process was confirmed in TEM image and Raman ratio, and the shearing force makes
the edge of graphene piece defective. When graphene is evenly dispersed, the wide specific surface area absorbs a great deal of light,
improving absorbance. We confirmed the absorbance of pristine graphene was showed below milling graphene and considerable
thermal conductivity increase compared to pristine graphene.
Keywords: Ball milling, Graphene, Nano-fluid, Physical process, Thermal conductivity
I. INTRODUCTION
Theoretical background: Emerging as a topic of nano scientific technology in 21st century, a range of nano carbon materials
including graphene, carbon nano tube and carbon nano fiber became familiar terms even to the general public and symbol of scientific
technology in the future. Graphene features having wider specific surface area, 200 times higher mechanical strength than steel but as
much flexibility, 100 times higher electrical conductivity than copper, more superior thermal conductivity (around 5000W/mk) than
diamond, optical characteristic of transmitting 97.7% of incident-light and high stability in structural and chemical way. Graphene is
also recognized as the highest potential core material that can replace the existing electronic device based on silicon as the mobility
of its electron in room temperature is 100 times as high as silicon, exceeding 200,000cm2/V᛫s. Since diverse chemical
functionalization of graphene is possible, the possibility of controlling its superior property was presented in a range of methodology,
resulting in active research on its application across industries such as electronic device, optical device, electrically conducting
composite material, sensor, clear electrode, transistor, organic solar cell, and composite material with ultra-light ᛫ high intensity. [1-5]
However, despite its superior property, the research on its applicable technology was very limited since the van der Waals’ forces
between graphene and its very stable chemical structure prevent graphene from being evenly distributed in solvent, making it difficult
to manufacture graphene nano-fluid with uniform feature. As a solution to such problem, research on making graphene distributed
evenly in solvent is being actively conducted via physical and chemical method.
The chemical method is separating graphene in solution state chemically via oxidant. Graphene oxide oxidized with strong acid and
oxidizer assumes strong hydrophilic property and is separated with ease via ultrasonic waves. The graphene oxide then undergoes the
reduction process additionally, turning into reduction graphene with structure and property equivalent to almost original graphene
though in not perfect state. The chemical method is also likely to have harmful effect on the environment in that the research on
applicable fields of graphene material will increase, and is unreasonable in terms of cost, thus generating active research on
environmental-friendly, inexpensive and novel stripping method than can replace the chemical method. [6-8] There is a manufacture
method of directly distributing graphene via surfactant without going through oxidation process. The method, however, has no
substantial effect due to the inter-layer resistance of nano-scale graphene pieces, and has fatal disadvantage that the dispersion in
nano-fluid is not improved than the chemical method and others. [9]
Meanwhile, the dispersed graphene in solution made by the chemical method has the advantage of being employed in various ways by
forming compound with other substances. Though reduced graphene assumes less electrical property than that made by mechanical
method, it is differentiated from other manufacture processes in its applicability such as solution process with low production cost, the
film thin and easy for mass production, and complex formation with other substances. The recent several studies revealed that the
layers of carbon allotropes are comparatively easily separated in the environment with shearing force acted, and if proper surface
stabilizer is employed at this stage in order to prevent re-cohesion, carbon allotropes are separated without chemical process to the
extent of at least three layers of graphene being stuck together.
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The typical ways to separate graphene physically via shearing force include dry milling method using hard particle, wet milling
method using both particle and solvent, and the method using supercritical state inducing explosive pressure change. Such methods
make it possible to embody environmental-friendly process that does not consume toxic chemicals, and are very suitable for
application using a great deal of graphene. As it is reported that the properties of graphene known theoretically can be exhibited in
reality, many scientists are actively studying on its applications across industries, pouring out performances ready for
commercialization. However, since the pure graphene is a hydrophobic material insoluble to most solvent, the reasonable and stable
process suitable for mass production should be employed in dispersing and floating graphene evenly in solvent in order to apply its
superb properties to industrial settings. [10, 11]
Purpose of study: In this study, ball milling process controllable a range of experiment conditions more easily and conveniently than
other physical methods was conducted so as to disperse graphene evenly in solvent and improve the resulting thermal conductivity.
With each ball diameter(1mm and 3mm), milling speed (200rpm, 400rpm, and 600rpm) and milling time (30min, 60 min) applied,
reducing the cohesive phenomenon of graphene was attempted, and features under each condition such as thermal conductivity of
nano-fluid containing graphene were compared and their correlation was evaluated.
II. EXPERIMENTAL RESULTS
TEM result: After ball milling process, whether graphene was milled was conformed via TEM prior to evaluating the effect of
milling. Graphene was observable via optical microscope due to the effect of light interference arising from multiple reflection of
graphene composed of 1 layer of carbon atom. In the Fig. 1 showing TEM images of pristine graphene and typical graphene gone
through ball milling process, the palest part corresponds to single layer. In the Fig. 1 (a) showing pristine graphene, the thin layers of
graphene were stuck together, and in the images of milled graphene of Fig. 1 (c), each layer of graphene was milled and dispersed via
ball milling. It was also revealed through the 1,000,000 times of image magnification that the pattern of edge of a piece of graphene
of Fig. 1 (b) was defective, which changed the pattern of the graphene particle as in Fig. 1 (d) via ball milling process. Therefore, the
effect of ball milling process on the milling of graphene was conformed in TEM image, and the shearing force by ball milling makes
the edge of graphene piece defective. [12, 13]
(a) (b)
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(c) (d)
Figure 1. TEM images: (a) A mass of the pristine graphene; (b) An edge of the pristine graphene; (c) A mass of the milling
graphene; (d) An edge of the milling graphene.
Thermal conductivity result: In this study, thermal conductivity of graphene nano-fluid based on distilled water was assessed in the
20~40°C of room temperature via thermal conductivity measuring equipment of Transient Hot water Technique. Prior to measuring
thermal conductivity, the measuring equipment was calibrated by comparing the thermal conductivity of distilled water with the
standard value. [14, 15] The result of thermal conductivity of the 10 samples depending on ball diameter, milling speed and milling
time, and pristine graphene before conducting ball milling process was presented in Fig. 2. The thermal conductivity of pristine
graphene without experiencing any process increased very subtly by 0.01% than that of distilled water used in nano-fluid. Given the
superior thermal property of graphene, the result was not satisfactory. It was revealed that when the pristine graphene alone was
dispersed in solvent, it was not possible to utilize the thermal, electrical and mechanical properties of graphene. In the condition of
applying ball milling method, the thermal conductivity increased the most at 60 min. of milling time and 200rpm of milling speed
regardless of the diameter of zirconia ball. When using 1mm size, it generally showed higher resulting thermal conductivity than 3mm
size. The extent of increase was 57E+6W/m*k and 46E+6W/m*k respectively compared to distilled water, showing considerable
increase compared to pristine graphene. The thermal conductivity under the other conditions also increased compared to pristine
graphene.
Figure 2. The result of the thermal conductivity
Raman Spectrometer result: The analysis on the optical property of graphene plays a pivotal role in the study on graphene. The data
that is not normally accessible optically due to its unique properties can be obtained via spectroscopy method, so the research on its
optical property has been conducted from the beginning of research. The Raman spectroscopy among others is the most essential
analysis method in the study of graphene as it is believed to be the surest way of identifying the single-layer graphene. Rayleigh
scatter means that when light travels through material, the light is scattered by the interaction of light and material, bringing along
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incident energy with it, whereas Raman scatter means that phonon is released or absorbed by lattice vibration, being scattered by
losing or getting as much energy. In particular, stokes Raman scatter meaning that light is scattered in as low energy as phonon energy
when phonon is released is used in most of the Raman spectroscope experiment. The information on crystal structure of material can
be obtained typically via Raman spectroscope analysis. [16, 17]
The graphitic materials such as graphite, carbon nanotubes, fullerene and graphene are based on hexagonal lattice, so Raman
spectrum is considerably similar. Fig 3 indicates Raman spectrum graph of pristine graphene, Sample 3 and Sample 8 which has the
high thermal conductivity according to diameter. The Fig. 3 shows that the most prominent Raman spectrum appeared in graphene is
G peak around 1580 and 2D peak around 2700. [18, 19]
These peaks are observed in carbon nanotubes, and graphitic materials have them in common. In particular, D peak, which can appear
around 1340, is shown when the hexagonal structure of carbon atom is defective or when the edge of graphene is measured. D peak
is almost invisible but at the edge of graphene via dynamic stripping process, whereas D peak is intense in graphene synthesized with
thermal chemical vapor deposition method. Therefore, how much graphene is defective is evaluated with D peak. In case of graphene
with much defect within crystal, D peak is only observed at the edge of the material or when sample contains much defect. The small
D peak of pristine graphene arises from the defect happened during the process of stripping graphene from graphite. [20-22] Sample
8 shows the relatively high peak when the shearing force acted to 3mm of zirconia during the ball milling process concentrated on the
edge of single layer of graphene. The 2D peak in Fig. 3 is used for identifying the single-layer graphene. While G peak show little
change in its shape and location in the Raman spectrum of double-layer graphene, 2D changes into complicated shape and becomes
wider, and whose relative intensity to G peak becomes weak. The 2D peak assessed in this study all represents the peak features of
single-layer of graphene. Raman spectroscope shows more obvious effect of ball milling process.
Figure 3. The result of the raman spectrum
The ratio of ID/IG indicates the consequence of external chemical or physical force. As the ratio of ID/IG is closer to 0, the law
material is closer to 100% of purity. [23] In the resulting Raman assessment, the ratio of ID/IG of Sample 3 was 0.36, the highest
ratio, that of Sample 8 was 0.33, and that of pristine graphene showed 0.21, the least ratio.1. In the ball milling process, the condition
of 60 min. and 200rpm of speed was the most optimal.
Table 1. The ratio of ID/IG.
Sample 11 Sample 3 Sample 8
ID/IG 0.21 0.36 0.33
UV-Spectrophotometer result: In order to be used as nano-fluid in heat exchanger employed in industrial settings, superior thermal
conductivity and the even dispersion and floating in fluid are very crucial factors. The thermal conductivity of nano-fluid
manufactured via ball milling process, the peak value of Raman spectroscope and the assessed result of ID/IG ratio were compared.
Along with that, the dispersibility of graphene was evaluated via UV experiment.
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Fig. 4 indicates the absorbance graph of manufactured graphene nano-fluid. In the graph, peak is shown at 260nm of the inherent
wavelength of graphene, and the dispersibility of graphene can be discerned by the result of absorbance. Basically, when graphene is
evenly dispersed and floated in nano-fluid, the wide specific surface area absorbs a great deal of light, improving absorbance. The
result of absorbance is proportional to that of thermal conductivity in Fig. 2. The pristine graphene shows the absorbance below 1.5,
cohering and precipitating faster than other samples. Consequently, graphene was dispersed and floated evenly in nano-fluid via ball
milling process, and the high thermal conductivity of nano-fluid was conformed. [24] In the conditions of 1mm ball, the absorbance
of sample2 is the highest and next is sample 3 and sample 1. As a result of 3mm ball, the absorbance increases sample 10, 9, 6, 7 and
8, in sequence. Comparing with the resulting thermal conductivity, it is corresponded exactly.
Figure 4. The result of the UV spectrum
III. MATERIALS AND METHODS
This study used graphene with 100m2
/g of specific surface area, 99.9% of purity, 8nm of average thickness of a piece, 550nm of
average particle size (150~3,000nm). In the milling process using planetary ball mill equipment, number of revolution, milling time,
ball size and ball charge have a great impact on milling, and dry or wet condition also leads to varied milling effects. Each condition
was applied to evaluate the effect of milling speed and milling time on the change of the properties of graphene in ball milling. To
prevent the inter-layer cohesive force of graphene, mixing it with distilled water was established as wet condition. Also, 1mm and
3mm of zirconia balls were used in order to assess the effect of diameter of balls. Table 2 represents the conditions of ball milling, and
nano-fluid was manufactured by using the identical graphene weight under each condition. Fig. 5 indicates the mimetic diagram of
planetary ball mill equipment used in this study. This equipment with two ports is designed in the way the circular main rotary valve
is rotated clockwise, and at the same time the two ports are rotated independently in the opposite direction of main rotary valve,
anti-clockwise. [25-28]
Table 2. The experimental conditions.
Sample Ball diameter Milling time Milling speed
1 1mm 30 minutes 400 rpm
2 1mm 30 minutes 600 rpm
3 1mm 60 minutes 200 rpm
4 1mm 60 minutes 400 rpm
5 1mm 60 minutes 600 rpm
6 3mm 30 minutes 400 rpm
7 3mm 30 minutes 600 rpm
8 3mm 60 minutes 200 rpm
9 3mm 60 minutes 400 rpm
10 3mm 60 minutes 600 rpm
11 No milling(Pure Graphene)
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Figure 5. Schematic diagram of ball milling
IV. MATERIALS AND METHODS
In this study, the nano-fluid used in heat exchanger was manufactured for application to industrial settings. Since the mass production
of nano-fluid in chemical way using complex oxidation and reduction process generates environmental pollution, the experiment was
conducted via physical way using zirconia ball with variables of ball size, milling speed and milling time in order to find out the
optimal condition of nano-fluid. The results of conducting the experiment with 11 samples are as follows.
① The effect of ball milling on the graphene milling was confirmed via the comparison of TEM images. Going through ball
milling process, the layers of graphene stuck together due to Vander Waals’ force were milled and separated.
② The fact that ball milling process has an impact on nano-fluid was confirmed via Raman spectroscope, and the result of thermal
conductivity was compared with that of UV absorbance. When the resulting thermal conductivity increases, both the
absorbance and Raman ratio increase.
③ The thermal conductivity was assessed in order to evaluate the performance of graphene as nano-fluid of heat exchanger.
Though the increase of thermal conductivity in the experiment seems insignificant, there is significance in that the
improvement of thermal conductivity was confirmed via simple and inexpensive process.
In order to manufacture more efficient nano-fluid later on, the synergy effect of the improvement of thermal conductivity can
be created by dispersing and milling graphene via relatively reasonable and safe ball milling process, and then by applying
chemical functional group to the opened tip of each edge of graphene via shearing force of ball milling.
V. ACKNOWLEDGEMENTS
This work was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by
the Ministry of Science, ICT and future planning (2015R1A2A2A01004579).
REFERENCES
1. Balandin, A. A., Ghosh, S., Bao, W., Calizo, I., Teweldebrhan, D., Miao, F. and Lau, C. N., Superior thermal conductivity of single-layer
graphene, Nano Letters, 8(3), 2008, 902–907.
2. Shahil, K. M. F. and Balandin, A. A., Thermal properties of graphene and multilayer graphene: Applications in thermal interface materials,
Solid State Communications, 152(15), 2012, 1331–1340.
3. Liu, J., Wang, F., Zhang, L., Fang, X. and Zhang, Z, Thermodynamic properties and thermal stability of ionic liquid-based nanofluids
containing graphene as advanced heat transfer fluids for medium-to-high-temperature applications, Renewable Energy, 63(2014), 2014,
519–523.
4. Assael, M. J.; Chen, C. F.; Metaxa, I.; Wakeham, W. A., Thermal conductivity of suspensions of carbon nanotubes in water, International
Journal of Thermophysics, 25(4), 2004, 971–985.
5. Gao, B., Hartland, G., Fang, T., Kelly, M., Jena, D., Xing, H. and Huang, L., Studies of intrinsic hot phonon dynamics in suspended graphene
by transient absorption microscopy, Nano Letters, 11(8), 2011, 3184–3189.
6. Lomeda, J. R., Doyle, C. D., Kosynkin, D. V, Hwang, W. and Tour, J. M., Diazonium functionalization of surfactant-wrapped chemically
converted graphene sheets, Journal of the American Chemical Society, 12(48), 2008, 16201–16206.
7. Hajjar, Z., Rashidi, A. morad and Ghozatloo, A. Enhanced thermal conductivities of graphene oxide nanofluids, International
Communications in Heat and Mass Transfer, 57(2014), 2014, 128–131.
8. Niyogi, S., Bekyarova, E., Itkis, M. E., Mcwilliams, J. L., Hamon, M. A. and Haddon, R. C., Solution Properties of Graphite and Graphene,
Journal of the American Chemical Society, 128(24), 2006, 7720–7721.
9. Wusiman, K., Jeong, H., Tulugan, K., Afrianto, H. and Chung, H., Thermal performance of multi-walled carbon nanotubes (MWCNTs) in
aqueous suspensions with surfactants SDBS and SDS, International Communications in Heat and Mass Transfer, 41(2013), 2013, 28–33.
10. Wang, G., Shen, X., Wang, B., Yao, J. and Park, J., Synthesis and characterisation of hydrophilic and organophilic graphene nanosheets,
Carbon 47(5), 2009, 1359–1364.
7. Grinding graphene characteristics after…
| Volume 1 | Issue 12 | www.ijrtem.com | 24 |
11. Bahr, J. L., Yang, J., Kosynkin, D. V., Bronikowski, M. J., Smalley, R. E. and Tour, J. M., Functionalization of carbon nanotubes by
electrochemical reduction of aryl diazonium salts: A bucky paper electrode, Journal of the American Chemical Society, 123(27), 2001,
6536–6542.
12. Liu, Z., Suenaga, K., Harris, P. J. F. and Iijima, S., Open and closed edges of graphene layers, Physical Review Letters, 102(1), 2009, 1–4.
13. Wang, G., Shen, X., Yao, J. and Park, J., Graphene nanosheets for enhanced lithium storage in lithium ion batteries, Carbon, 47(8), 2009,
2049–2053.
14. Natarajan, E. and Sathish, R., Role of nanofluids in solar water heater, The International Journal of Advanced Manufacturing Technology,
2009, 1–5.
15. Ahammed, N., Asirvatham, L. G., Titus, J., Bose, J. R. and Wongwises, S., Measurement of thermal conductivity of graphene-water nanofluid
at below and above ambient temperatures, International Communications in Heat and Mass Transfer, 70, 2016, 66–74.
16. León, V., Quintana, M., Herrero, M. A., Fierro, J. L. G., Hoz, A. D. La, Prato, M. and Vázquez, E., Few-layer graphenes from ball-milling of
graphite with melamine, Chemical Communications, 47, 2011, 10936-10938.
17. Eckmann, A., Felten, A., Mishchenko, A., Britnell, L., Krupke, R., Novoselov, K. S. and Casiraghi, C., Probing the nature of defects in
graphene by Raman spectroscopy, Nano Letters, 12(8), 2012, 3925–3930.
18. Ferrari, A. C., Meyer, J. C., Scardaci, V., Casiraghi, C., Lazzeri, M., Mauri, F., Mauri, S., Piscanec, D. jiang; K.S.Novoselov, S.Roth and
Geim, A. K., Raman spectrum of graphene and graphene layers, Physical Review Letters, 97(18), 2006, 1–4.
19. Calizo, I., Ghosh, S., Bao, W., Miao, F., Ning Lau, C. and Balandin, A. A., Raman nanometrology of graphene: Temperature and substrate
effects, Solid State Communications, 149(27-28), 2009, 1132–1135.
20. Renteria, J., Nika, D. and Balandin, A., Graphene Thermal Properties: Applications in Thermal Management and Energy Storage, Applied
Sciences, 2014, 4(4), 525–547.
21. Dresselhaus, M. S., Jorio, A., Hofmann, M., Dresselhaus, G. and Saito, R., Perspectives on carbon nanotubes and graphene Raman
spectroscopy, Nano Letters, 10(3), 2010, 751–758.
22. Ni, Z. H., Yu, T., Lu, Y. H,; Wang, Y. Y., Feng, Y. P. and Shen, Z. X., Uniaxial strain on graphene: Raman spectroscopy study and band-gap
opening, ACS Nano, 2(11), 2008, 2301–2305.
23. Jorio, A., Raman Spectroscopy in Graphene-Based Systems: Prototypes for Nanoscience and Nanometrology, ISRN Nanotechnology 2012,
1–16.
24. Li, X., Chen, Y., Mo, S., Jia, L. and Shao, X., Effect of surface modification on the stability and thermal conductivity of water-based
SiO2-coated graphene nanofluid, Thermochimica Acta, 595(10), 2014, 6–10.
25. Jeon, I.-Y., Choi, H.-J., Jung, S.-M., Seo, J.-M., Kim, M.-J., Dai, L. and Baek, J.-B., Large-Scale Production of Edge-Selectively
Functionalized Graphene Nanoplatelets via Ball-Milling and Their Use as Metal-Free Electrocatalysts for Oxygen Reduction Reaction,
Journal of the American Chemical Society, 135(4), 2012, 1386–1393.
26. Bastwros, M., Kim, G. Y., Zhu, C., Zhang, K., Wang, S., Tang, X. and Wang, X., Effect of ball milling on graphene reinforced Al6061
composite fabricated by semi-solid sintering, Composites Part B: Engineering, 60, 2014, 111–118.
27. Zhao, W., Wu, F., Wu, H. and Chen, G., Preparation of colloidal dispersions of graphene sheets in organic solvents by using ball milling,
Journal of Nanomaterials 2010, 6, 2010, 1-5.
28. León, V., Rodriguez, A. M., Prieto, P., Prato, M. and Vázquez, E., Exfoliation of Graphite with Triazine Derivatives under Ball-Milling
Conditions: Preparation of Few-Layer Graphene via Selective Noncovalent Interactions, ACS Nano, 8(1), 2014, 563–571.