Laser cleaning of materials’ surfaces implies the removal of deposited pollutants without affecting the material. Nanosecond Nd:YAG pulsed laser, operating at 1064 nm and 532nm, was utilized. Different laser intensities and number of pulses were used on metallic and non-metallic surfaces under O2 and Ar environments to remove metal oxide and crust. Cleaning efficiency was studied by optical microscope. The results indicated the superiority of 1064 nm over the 532 nm wavelength without any detectable damage to materials’ surfaces. Marble cleaned in Oxygen gas environment was better than in Ar gas.
Iraq suffers from serious pollution with harmful particles that have important direct and indirect effects on human activities and human health. In this research, a system for detecting pollutants in the air was designed and manufactured using infrared laser technology. This system was used to detect the presence of pollutants in the dust storms that swept the city of Baghdad which could have a negative impact on human health and living organisms.
The designed detection system based on the use of infrared laser (IR) with a wavelength of 1064 nm was used for the purposes of detecting pollutants based on the scattering of the laser beam from these pollutants. The system was aligned to obtain the best signal for the scattered rays, w
... Show Moreيشغل المجال النووي الايراني اهتمام دولي كبير الامر الذي جعل من الولايات المتحدة الامريكية تفرض قيودا اقتصادية على ايران لتحجيم دورها في المنطقة
Предметом нашего исследования является вводные слова и их значения в современном русском языке. И прежде чем углубиться в нашу научную работу нам было необходимо определить понятие вводных слов и их функция и место в системе русского языка. По словам В. Г. Лебедева и Л. С. Тюревы "Вводные слова вводятся в предложении, чтобы выражать отношение говорящего к высказываемой мысли, оценки ее содержа
... Show Moreمن المؤسف حقا ان نجد أنفسنا نعيش في ظروف عصيبة لم تشاهده أعيننا ولم تطرأ على مسامعنا من قبل، وجاء الاحتلال البغيض بكل تبعاته السلبية افرز عنه اليوم تفرقاً ملحوظا وصراعا اليماً وتناحراً أضر بمكانتنا ووحدتنا، ولنا في كل يوم مصيبة وعويل، حتى صارت عبارة عن مذاهب وطوائف وأشخاص، تتنازعهم الأهواء والخرافات والتقليد والتعصب وأمراض أخرى، وباتت تلك الأشلاء يلعن بعضها بعضاً وينفي أحدها الآخر.
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... Show MoreFind a study in the relationship between geography and medicine and a variety of sources, this study multiple. Valjgraveh is the image of the earth recipe haunted them and which of the seven regions and seas and mountains, prairies, rivers and cities geographical study of the Earth as the abode of the person or is the study of the natural environment of the human race and the geographical that analyzes the different factors that make up the natural environment and examines the impact of each factor separately and then the effects of all factors combined to human life and health and activity.
The effect of different cutting fluids on surface roughness of brass alloy workpiece during turning operation was carried out in this research. This was performed with different cutting speed, while other cutting parameters had been regarded as constants(feeding rate , and depth of cut). Surface roughness of machined parts that will be tested by electronic surface roughness tester .The results show that the standard coolant gives the best values of surface roughness for fixed cutting speed ,followed by sun flower oil that has approximately the same effect, while the air stream as a coolant gave unsatisfied results for the evaluation of surface roughness.
In the other hand the best values of surface roughness were recorded for max
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oday deep ocean life has not been discovered by humans including many secret world things to be explored. The researcher has focused on underwater optical wireless communications using various kinds of complex digital Signal processing most of them used in air and starting applied in underwater communication. The Internet of Things (IoT) uses underwater called Internet of Underwater Things (IoUT) applications to explore the underwater world with other devices. However, the difference in concentration between air and water surfaces is not easy making wireless communication more complicated. Visible light passes the water's surface with scattering and distortion inside the water and each color of light has different attenuation the blue laser
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