AO Dr. Ali Jihad, Journal of Physical Education, 2021
This research study the effect of Titanium dioxide on the tensile properties of
Polystyrene (PS) and Polycarbonate (PC) polymers. The stress – strain curve for pure PS
and pure PC, shows that Young modulus for PS is higher than Young modulus for PC,
because PS have higher ultimate strength than PC.
The addition of TiO2 to PS and PC will reduce the Young modulus and ultimate stress,
because the TiO2 particles will reduces or freeze the orientation of these molecular chain
and reduced the toughness of PC, while when the TiO2 were added to PS, the value of
toughness will be stabilized because TiO2 particles make these chains interlocked and the
mobility of the chains will be restrict.
In this study, the effect of ceramic coating on the performance and gases emission on diesel engine was investigated. A four-stroke, direct injected, single cylinder, diesel engine was tested at constant speed and at different load conditions without coating. Then, the inlet and exhaust valves faces were coated by about 500µm with ceramic materials. Ceramic layers were made of YttriaStabilized Zirconia (YSZ), and NiCrAl as a bond coat. The coating technique adapted in this work is the flame spray method. The engine with valves ceramiccoated research was tested for the same operation conditions of the engine (without coating). The results indicate a reduction in both fuel consumption by about 7.6% and particulate emissions by about (13
... Show MoreConcrete pavements are essential to modern infrastructure, but their low tensile and flexural strengths can cause cracking and shrinkage. This study evaluates fiber reinforcement with steel and carbon fibers in various combinations to improve rigid pavement performance. Six concrete mixes were tested: a control mix with no fiber, a mix with 1% steel fiber (SF1%), a mix with 1% carbon fiber (CF1%), and three hybrid mixes with 1% fiber content: 0.75% steel /0.25% carbon fiber (SF0.75CF0.25), 0.25% steel /0.75% carbon fiber (SF0.25CF0.75), and 0.5% steel /0.5% carbon fiber ((SF0.5CF0.5). Laboratory experiments including compressive, flexural, and splitting tensile strength tests were conducted at 7, 28, and 90 days, while Finite Element Analys
... Show MoreFree radicals and oxidative damage caused by them have being suggested to be involved in the pathogenesis of migraine. These may result from distorted equilibrium of pro-oxidant/anti-oxidant system that continuously generates and detoxifies oxidants during normal aerobic metabolism. Escape of such system from equilibrium leads to damage of cellular elements with the depletion of cellular stores of anti-oxidants material such as glutathione and vitamin E. Therefore, free radical scavengers (vitamin E or melatonin) seems to be of potential benefit as prophylactic anti-migraine therapy by neutralizing free radicals overproduction and possibly preventing formation of highly toxic intermediates (such as nitric oxide). In addition of being pow
... Show MoreQuality control charts are limited to controlling one characteristic of a production process, and it needs a large amount of data to determine control limits to control the process. Another limitation of the traditional control chart is that it doesn’t deal with the vague data environment. The fuzzy control charts work with the uncertainty that exists in the data. Also, the fuzzy control charts investigate the random variations found between the samples. In modern industries, productivity is often of different designs and a small volume that depends on the market need for demand (short-run production) implemented in the same type of machines to the production units. In such cases, it is difficult to determine the contr
... Show MoreAbstract:
Recently, there is a widespread attention about the service at the level of each of the research and academic studies, and at the organizational level as well. The subject of orientation towards the service aspect is starting to be of this attention being of the modern subjects, relatively, which appeared at the end of the last century, as well as the link of this subject with the relationship between the organization and its customers, and how to provide high quality services to get their satisfaction. Thus, the specialists from researchers were interested in this field to develop an appropriate scale to measure the organizational orientation toward service, and it was the most prominen
... Show Moreولاء طارق حميد, Mustansiriyah Journal of Sports Science, 2021
The steel jetty selected for strengthening is in Baghdad city, over Tigris River, consists of 55 short spans, each of approximately 4 meters and one naviga-tional opening of 12 m. The bridge is 224 meters length and 8 meters in width. The strengthening system was designed to remove overstresses that occurred when the bridge was subjected to abnormal loads of 380 tons. A strengthening system which installed in spring 2008 was used where the main concept is to depend on added side supporting elements which impose reversal forces on the bridge to counteract most of the loads expected from the abnormal heavy loads. The bridge was load tested before and after the strengthening system was activated. The load test results indicate that the strengt
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