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Abstrak :
ABSTRACT
The carbon dioxide laser is one of the most versatile types on the marked today. It emits infrared radiation between 9 and 11 micrometer (μm) either at a single line selected by the user or on the strongest line in untuned cavities. It can produce continuous output power output powers ranging from well under 1W for scientific applications to many kilowatts for material working.

It can generate pulses from the nanosecond to millisecond regimes. Custom made CO2 lasers have produced continues beams of hundreds of kilowatts for military laser weapon research (Hecht 1984) or nanosecond long pulses of 40 kilo joules (kj) for research in laser induced nuclear fusion (Los Alamos National Laboratory 1982).

This versatility comes from the fact that there are several distinct types of carbon dioxide lasers. While they share the same active medium, they have important differences in internal structure and more important to the user in lunch oral characteristic. In theory the structural variations could range over a really continuous spectrum, but manufactures have settled on a few standard configurations which meet most user needs. This users see several distinct types, such as waveguide, low power sealed tube, high power following gas, and pulsed transversely excited CO2 lasers.

On TEA lasers discharge instabilities make continuous wave operation impractical at gas pressures above about 100 torr (13,3 MPa). How everit is possible to produce pulses lasting tens of nanosecond to microseconds. Such lasers are called transversely excited atmospheric (TEA) lasers because they operate at or near atmospheric pressure, although same times the term is applied to pulsed transversely excited CO2 lasers which operate at higher or lower pressures. The TEA lasers prime attraction of high power per unit volume of laser gas and have fairly complex power requirements because of the nature of their pulsed operation. Typically same energy in the form of electrons or ultraviolet photons is discharged into the laser gas slightly before the main pulse to make it possible to obtain higher output power. In this thesis, basic theory of the Carbon dioxide laser are presented in section II.

Section III descibe Optical Transducer. Section IV contains the characterization of carbon dioxide laser with the results and graphs.

Finally some conclusion regarding our discussion are summarized in section V.

Abstrak :
ABSTRACT
The construction and excitation circuit of carbon dioxide laser 616 mm long is described. The dependence of the pulse emission energy on the energy supplied to the discharge, the pressure and composhdon gaseous mixture is presented. The emission energy is 1-2 Joules. The emission pulse isexpected to cover range from 100 ns - 200 ns.

Abstrak :
Banyak penelitian yang menunjukan kemampuan laser untuk proses fabrikasi Beberapa tahun terakhir teknologi laser telah dicoba diaplikasikan untuk pembuatan microchannel untuk menigkatkan efisiensi waktu pembuatan microchannel. Karena microchanel memerlukan kepresisian tinggi maka perlu diperhatikan aspek aspek yang mempengaruhi output laser yaitu model laser jenis laser dan material yang digunakan. Pada penelitian ini digunakan laser CO2 software MATLAB dan ANSYS Parameter Desaign Language APDL dengan material acrylic untuk analisis microchannel. Analisis yang digunakan dalam penelitian ini adalah analisis dalam tingkat mikro dengan memperhatikan parameter daya kecepatan dan diameter laser beam. Distribusi yang digunakan di sini adalah distribusi gauss yang menghasilkan grafik distribusi intensitas dan distribusi temperatur Kedua distribusi ini ditunjukan pada arah x y dan z. Data hasil dari simulasi Matlab digunakan sebagai pembanding dengan data hasil eksperimen Setiap grafik dianalisis secara seksama dan dilihat nilai temperature telah mencapai titik lebur dari acrylic. Hasil simulasi ini menunjukan distribusi panas menggambarkan area pemotongan dari laser yang menunjukan kedalaman lebar dan seberapa curam grafik pada bidang xz. Kecuraman grafik ini menunjukan pengaruh kecepatan dari laser terhadap kekasaran. Dari simulasi ini dapat disimpulkan bahwa daya lebih berpengaruh terhadap lebar dibandingkan terhadap kedalaman. Semakin cepat pergerakan laser maka hasil pemotongan akan semakin kasar APDL digunakan untuk mengetahui distribusi temperatur pada material acrylic dan pengaruh diameter beam. Hasil penelitian ini diharapkan bisa dijadikan acuan jika ingin melakukan rekontruksi pada mesin laser CO2.

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Many studies had showed the ability of the laser to the fabrication process. In recent years laser technology has been applied to make microchannel and to improve the efficiency of making microchannel. Because microchannel need high precision it is necessary to consider the aspects that influences the output laser wich are laser models laser types and materials that used. This study uses CO2 laser MATLAB and APDL with acrylic material for microchannel analysis. This study uses the analysis of the micro level that takes into account the parameter of power speed laser beam diameter and uses the gauss distribution that produces graphs of intensity and temperature distribution. The two distribution is shown in the direction of x y and z. The results of Matlab simulation used as comparison with the machining data. Each graphs is analyzed carefully and observed the value of the temperature has reached the melting point of acrylic or not. This simulation shows the heat distribution that describes the area of laser cutting either the depth or width and also how steep the graphs in the plane xz does. The steepness of graphs show the influence of the laser velocity on roughness. From this simulation it can be concluded that power has more influence the width than the depth. The faster the movement of the laser the more roughness will be produced APDL is used to determine the temperature distribution in acrylic material and the influence of beam diameter. Therefore the result is expected to be a reference to the reconstruction of the CO2 laser machine.

Abstrak :
Adanya permasalahan mengenai tingkat emisi CO2, menyebabkan meningkatnya kesadaran untuk mengurangi emisi CO2 dengan penelitian untuk mengembangkan teknologi Carbon Capture, Storage, and Utilization (CCSU). Dikarenakan sumber magnesium silicate melimpah dan mudah untuk ditemukan di dunia, magnesium silicate digunakan untuk mengurangi emisi CO2dengan menangkap dan menyimpan CO2 menggunakan carbon capture storage (CCS). Pada penelitian ini, magnesium silicate diberikan perlakuan leaching untuk memulihkan kandungan unsur magnesiumnya. Filtrat hasil proses leachingakan digunakan untuk proses karbonasi dengan penambahan NH3 dan diinjeksikan oleh tekanan gas CO2. Perlakuan karbonasi menggunakan temperatur sebagai variabel bebas dengan variasi 30, 40, dan 50oC. Karakterisasi yang dilakukan yaitu pengujian X-ray Diffraction (XRD), X-Ray Fluorescence (XRF), Scanning Electron Microscope – energy dispersive X-ray (SEM–EDS), dan Inductively coupled plasma-optical emission spectrometry (ICP-OES) yang bertujuan untuk mengetahui morfologi mikrostruktur permukaan dan kandungan senyawa yang dihasilkan dari percobaan. Dari proses karbonasi didapatkan bahwa semakin tinggi temperatur proses karbonasi menghasilkan peningkatan konsentrasi unsur magnesium pada endapan yang dihasilkan. Pada proses karbonasi yang diinjeksi CO2 dengan penambahan NH3 membentuk senyawa hydromagnesite (Mg5(CO3)4(OH)2·4H2O), magnesium carbonate (MgCO3), dan calcium carbonate (CaCO3). ......The existence of problems regarding CO2 emission levels has led to increased awareness to reduce CO2 emissions with research to develop Carbon Capture, Storage, and Utilization (CCSU) technology. Because the source of magnesium silicate is abundant and easy to find in the world, magnesium silicate is used to reduce CO2 emissions by capturing and storing CO2 using carbon capture storage (CCS). In this study, magnesium silicate was treated with a leaching process to recover magnesium content. The leaching filtrate will be used for the carbonation process with the addition of NH3 and injected with CO2 gas pressure. The carbonation treatment uses temperature as an independent variable with variations of 30, 40 and 50oC. The characterization carried out was testing X-ray Diffraction (XRD), X-Ray Fluorescence (XRF), Scanning Electron Microscope-energy dispersive X-ray (SEM–EDS), and Inductively coupled plasma-optical emission spectrometry (ICP-OES) which aims to determine the morphology of the surface microstructure and the content of the experimental compounds. From the carbonation process it is known that the higher the temperature of the carbonation process results in an increase in the concentration of the element magnesium in the resulting precipitate. In the carbonation process, CO2 is injected with the addition of NH3 to form hydromagnesite (Mg5(CO3)4(OH)2·4H2O), magnesium carbonate (MgCO3), dan calcium carbonate (CaCO3).