In this research, damping properties for composite materials were evaluated using logarithmic decrement method to study the effect of reinforcements on the damping ratio of the epoxy matrix. Three stages of composites were prepared in this research. The first stage included preparing binary blends of epoxy (EP) and different weight percentages of polysulfide rubber (PSR) (0%, 2.5%, 5%, 7.5% and 10%). It was found that the weight percentage 5% of polysulfide was the best percentage, which gives the best mechanical properties for the blend matrix. The advantage of this blend matrix is that; it mediates between the brittle properties of epoxy and the flexible properties of a blend matrix with the highest percentage of PSR. The second stage included reinforcing the best blend matrix of epoxy-polysulfide (the blend matrix with the best percentage of polysulfide resulted from the previous stage), by different volume percentages of short fibers (Carbon& Glass) separately and randomly. The volume percentages of fibers were (2.5%, 5%, 7.5%, and 10%). The third stage included reinforcing the blend composites with highest percentages of carbon and glass fiber, by different weight percentages of nano-particles (Red mud& Fly ash) separately. The weight percentages of particles were (0.5%, 1%, 1.5%, and 2%). The experimental results showed that blending polysulfide rubber with epoxy increased the damping ratio. As for reinforcement materials, they decreased the damping ratio, where glass fiber composites have significantly higher damping ratio than other composites.
Abstract
Nowadays, the world adopts a philosophy that relates to environmental conservation. This philosophy can be achieved through providing environmentally friendly products while satisfying customers' needs as well. To attain that, a new systems and programs need to be applied in a scientific manner, and total quality environmental management (TQEM) is among these concepts. The research aimed to analyze the Relationship between (TQEM) Practices and its effect on Flexible Manufacturing in Badush factory. The research sample includes managers and head of divisions at top, middle and front line management levels which were (27) working in Badush factory. To achieve the objectives of the study, the descriptive anal
... Show MoreThe research aims to answer the questions that revolve in the mind of mankind about how to create creation, how it existed prior to creation, who created existence, and the characteristics of that presence. The researcher also wanted to show that the culture of Imam Ali (peace be upon him) In the book of Adam, peace be upon him, God has punished Adam (peace be upon him) for not having sinned. Because his wife is the one who fed him the fruit of the tree, and this is contrary to what was stated in the sermon of Imam (peace be upon him) who Z Adam (peace be upon him) is the one who trusted Satan and Gwighth.
We note that the approach of the rhetoric has pointed to the creation of angels and did not refer to
... Show MoreThe research aims to answer the questions that revolve in the mind of mankind about how to create creation, how it existed prior to creation, who created existence, and the characteristics of that presence. The researcher also wanted to show that the culture of Imam Ali (peace be upon him) In the book of Adam, peace be upon him, God has punished Adam (peace be upon him) for not having sinned. Because his wife is the one who fed him the fruit of the tree, and this is contrary to what was stated in the sermon of Imam (peace be upon him) who Z Adam (peace be upon him) is the one who trusted Satan and Gwighth.We note that the approach of the rhetoric has pointed to the creation of angels and did not refer to the creation of Eve and the class
... Show MoreThe oxidative degradation of Orange G dye by nanosized CeO2 catalyst has been performed in this study. The catalyst was prepared by precipitation method. Various characterization techniques were carried out to study the physical and chemical properties of the synthesized catalyst. The XRD result confirms well the formation of CeO2 cubic phase. The FTIR result showed the effect of calcination temperature for CeO2 was clearly observed due to reduction in band intensity compared to uncalcined Ce nitrate sample. Meanwhile, the diffused reflection spectra recorded reflection spectra at 414 nm with an energy gap of 3.2 ev. The decolorization of Orange G dye by oxidation process were carried out unde
... Show MoreThe current research aims to investigate the effect of a specimen of Daniel in the acquisition of concepts for the Arabic language curricula material to the students of the third phase of the Faculty of Basic Education Department of Arabic Language. The sample consists of (93) applications and a student of (47) students in the Division (A), which represents the experimental group which studied the use of a specimen of Daniel, and (46) students in the Division (B), which represents the control group, which studied the traditional way. The subject of unified two groups, which subjects the Arabic language curricula which includes six chapters.
The duration of the experiment is a full semester. The researchers also prepared a tool for mea
The aim of this research is to investigation the optimization of the machining parameters (spindle speed, feed rate, depth of cut, diameter of cutter and number of flutes of cutter) of surface roughness for free-form surface of composite material (Aluminum 6061 reinforced boron carbide) by using HSS uncoated flat end mill cutters which are rare use of the free-form surface. Side milling (profile) is the method used in this study by CNC vertical milling machine. The purpose of using ANFIS to obtain the better prediction of surface roughness values and decreased of the error prediction value and get optimum machining parameters by using Taguchi method for the best surface roughness at spindle speed 4500 r.p.m, 920mm/rev feed rate, 0.6mm de
... Show MoreThis study investigated the structural behavior of a beam–slab member fabricated using a steel C-Purlins beam carrying a profile steel sheet slab covered by a dry board sheet filled with recycled aggregate concrete, called a CBPDS member. This concept was developed to reduce the cost and self-weight of the composite beam–slab system; it replaces the hot-rolled steel I-beam with a steel C-Purlins section, which is easier to fabricate and weighs less. For this purpose, six full-scale CBPDS specimens were tested under four-point static bending. This study investigated the effect of using double C-Purlins beams face-to-face as connected or separated sections and the effect of using concrete material that contains different recycled
... Show MorePreparing teacher occupies the attention of many thinkers and philosophers since the age of
kaldinics ( people of mesoptam / 2342 pH ) to the Islamic age where moslems philosophers
focus their attention on thought and philosophy where the philosophy of that teaching
depends on : teacher , student and family begin .
So , the issue of preparing and training teacher occupies the attention of education scientists
depending on his vital and important role in implementing of teaching policies in philosophies
and Islamic educational thought , therefore , the preparing and development of the teacher
regards as one of the basics of teaching development because of its importance in
development of teaching performance and th
The objective of this research is to measure the training programs and identify the nature and then measure how it reflected on the quality of municipal services provided by the municipal departments investigated by measuring the quality of services based on quality standards, the researcher chose four municipal departments in the Rusafa / Baghdad (164 people) representing the directors and their assistants, officials of the municipal departments, the people and the engineering staff in charge of the task forces as well, including the survey of the views of the concerned persons in the management of the Vocational Training Institute in the Secretariat of the Republic, The quality of the municipal services
... Show MoreThe objective of this study is to explain the role of credit policies in agricultural development of Iraq during the period 1979-1989 which were represented by the policy of co-operative agricultural bank the organization that responsible to finance agricultural sector for various reasons. It has been shown that there was no clear credit policy existed during the period concerned due to the differences between loans from year. The loan growth rate was low in general comparing with objectives of the agricultural development plans, a low production rates comparing with loans paid, the growth rate of average number of trees in each donum and the growth rate of livestock number was also low.In conclusion there should be a clear plan for cred
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