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"Eksperimen menggunakan Spektroskopi Emisi Inframerah dilaksanakan pada sampel logam untuk memperoleh model termal. Eksperimen ini bertujuan untuk mengidentifikasi korosi tahap awal pada logam. Dengan ini, memperoleh konklusi mengenai potensi perkembangannya dalam teknologi pendeteksi korosi. Dikarenakan batasan-batasan eksperimen yang dilaksanakan, model yang diperoleh hanya menunjukkan pola pola perubahan, melainkan angka. Eksperimen menggunakan spektroskopi emisi inframerah dilaksanakan untuk mengukur radiasi benda hitam dari sampel baja ringan, baja tahan karat, serta alumunium saat mereka mengalami korosi pada temperature tinggi. Eksperimen ini diikuti dengan membelah sampel dan melakukan analisis komponen menggunakan Mikroskop Elektron. Pada tahap ini telah dikonfirmasi bahwa korosi tahap awal terdeteksi. Dalam validasi dan verifikasi data agar dapat digunakan dalam model, eksperimen Light Flash Apparatus (LFA) serta analisa mikrosop elekreon dilaksanakan untuk memperoleh data lengkap mengenai komposisi dan properti sampel.

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Experiments were run utilising Infrared Emission Spectroscopy (IES) as a tool to produce a thermal model, aiming to identify early stages of metal corrosion under operating temperatures. In turn, determining the feasibility of this technology to for use in corrosion identification. Due to experimental limitations, model produced only determined patterns that exhibit the presence of corrosion instead of an exact numerical representation. An Infrared Emission Spectroscopy (IES) experiment was conducted to measure the blackbody radiation emitted by mild steel, stainless steel and aluminium metallic samples as they corrode at high temperatures. A post processing method was then undertaken to section and embed the corroded samples in a solid resin for elemental composition analysis under an Electron Scanning Microscope. Concluding the completion of an initial array of experimentation, the utilised experimental methods have resulted in the detection of early stage corrosion. Therefore, to validate and verify data that can be utilised for construction of a computational model by utilising further SEM and Light Flash Apparatus (LFA) experimentation to gather additional details on the elemental and thermal properties of the corroded samples to develop the theoretical model."

"Dilakukan studi tentang ketahanan korosi baja tahan karat austenitik seri 304L pada berbagai konsentrasi larutan NaCl. Percobaan dilakukan dengan metode electrochemical impedance spectroscopy EIS pada temperatur ruang yang bertujuan untuk mengevaluasi mekanisme korosi sampel berdasarkan tahanan polarisasi dan impedansi kapasitansinya.Percobaan dilakukan dalam berbagai konsentrasi larutan NaCl, yaitu 1 , 2 , 3.5 , 4 and 5 w.t. Hasil percobaan, yang direpresentasikan dengan grafik Nyquist dan rangkaian listrik ekuivalen, menunjukkan bahwa besarnya impedansi sampel, yang mana menunjukkan ketahanan korosinya, dipengaruhi oleh konsentrasi larutan NaCl. Besarnya nilai impedansi baja tahan karat 304L dari yang paling tinggi ke yang paling rendah berada pada larutan NaCl dengan konsentrasi: 1 , 2 , 5 , 4 , 3.5 w.t NaCl. Telah diamati bahwa ketahanan korosi terendah dari sampel berada pada larutan NaCl konsentrasi 3.5 w.t NaCl, yang mana serupa dengan air laut pada umumnya. Hal ini terjadi karena kelarutan optimimum dari oksigen terlarut terjadi pada larutan NaCl konsentrasi 3.5 w.t.NaCl. Kata kunci : Baja tahan karat 304L, Perilaku Korosi, Ketahanan Korosi, pengaruh konsentrasi NaCl, electrochemical impedance spectroscopy.

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Corrosion behavior of austenitic stainless steel 304L type in various concentrations of aqueous sodium chloride solutions was investigated. Experimental testing method was carried out by using electrochemical impedance spectroscopy EIS at room temperature 27oC to evaluate the change of corrosion mechanism based on its polarization resistance and capacitive impedance.Aqueous sodium chloride solutions were prepared with various concentration i.e. 1 , 2 , 3.5 , 4 and 5 w.t. The testing results which were represented by Nyquist graphs and electrochemical equivalent circuits showed that the impedance magnitudes of austenitic stainless steel which indicated its corrosion resistance were influenced by sodium chloride concentrations. Rank of impedance magnitude of SS 304L at various chloride concentrations from the highest to the lowest were 1 , 2 , 5 , 4 , 3,5 w.t NaCl consecutively. It was observed that the lowest corrosion resistance of alloys was at 3,5 w.t NaCl which was similar to typical seawater solution. This was caused by the presence of maximum dissolved oxygen solubility."

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Dalam industri minyak dan gas, korosi yang diakibatkan oleh karbon dioksida masih menjadi tantangan yang besar yang dapat menyebabkan kegagalan material. Penelitian ini menggunakan salah satu turunan dari senyawa piridin sebagai inhibitor yang dapat ditambahkan ke dalam sistem perpipaan untuk mengurangi laju korosi. Piridin ini diteliti dengan variasi konsentrasi, yaitu 25 ppm, 50 ppm, dan 75 ppm, serta variasi temepratur, yaitu 40° dan 90°C. Pengujian Fourier Transform Infrared Spectroscopy (FTIR) dan Gas Chromatography – Mass Spectrometry (GCMS) dilakukan untuk mengkarakterisasi inhibitor, dimana ditemukan bahwa inhibitor ini memiliki molekul dengan heteroatom nitrogen yang dapat memfasilitasi proses adsorpsi. Efisiensi inhibisi korosi juga diukur menggunakan metode polarisasi linear dan Electrochemical Impedance Spectroscopy (EIS), dimana ditemukan bahwa laju korosi menurun dengan meningkatnya konsentrasi inhibitor dan meningkat dengan meningkatnya temperatur. Data dari pengujian elektrokimia juga digunakan untuk menentukan model adsorpsi isoterm dan tipe adsorpsi, dimana ditemukan bahwa model adsorpsi yang didapat adalah adsorpsi isoterm Langmuir dengan tipe adsorpsi campuran fisika dan kimia. Morfologi permukaan sampel juga diteliti menggunakan Scanning Electron Microscopy (SEM) dan Energy Dispersive X-Ray (EDX) dan hasilnya menunjukkan bahwa sebelum diberikan inhibitor, produk korosi mendominasi permukaan dan jumlahnya menurun secara drastis setelah inhibitor diberikan, menandakan bahwa inhibitor ini telah sukses untuk menurunkan laju korosi baja karbon pada lingkungan CO₂.

 

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In oil and gas industry, corrosion caused by carbon dioxide is one of the greatest challenges that could lead to material failure. This research uses a derivative of pyridine as an inhibitor that can be added to the piping system to reduce the rate of corrosion. Pyridine was examined with variations in concentration, namely 25 ppm, 50 ppm, and 75 ppm, as well as variations in temperature, namely 40° and 90°C. Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatography - Mass Spectrometry (GCMS) tests were performed to characterize the inhibitors, which found that these inhibitors have molecules with nitrogen heteroatoms that can facilitate the adsorption process. The efficiency of corrosion inhibition was also measured using the potentiodynamic polarization method and Electrochemical Impedance Spectroscopy (EIS), which found that the corrosion rate decreased with increasing inhibitor concentration up to an optimal concentration of 50 ppm and increased with increasing temperature. The data from electrochemical testing was also used to determine the adsorption model of the isotherm and the type of adsorption, and it was found that the adsorption in this system obeyed Langmuir isotherm adsorption and is governed by a mixture of physical and chemical type. The surface morphology of the samples was also investigated using Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray (EDS) and the results showed that before injected with inhibitors, corrosion products dominated the surface and the amount decreased dramatically after the inhibitor was given, indicating that this inhibitor was successful to reduce the rate of carbon steel corrosion in the CO₂ environment.

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"The book will discuss the published experimental techniques, data-processing algorithms, and approaches used in FT-IR spectroscopy to assist in the characterization and identification of microorganisms, to assess the mechanisms of bacterial inactivation by food processing technologies and antimicrobial compounds, to monitor the spore and membrane properties of foodborne pathogens in changing environments, to detect stress-injured microorganisms in food-related environments, to assess dynamic changes in bacterial populations, and to study bacterial tolerance responses."

"Telah dilakukan penelitian mengenai aplikasi teknologi FTIR untuk mendeteksi masa subur lutung jawa (Trachypithecus auratus) betina. Penelitian ini bertujuan untuk mengetahui bilangan gelombang yang merepresentasikan gugus fungsi dari hormon metabolit estrone conjugate (E1C) maupun pregnanediol-3-glucuronide (PdG) pada sampel urine lutung jawa dan dikaitkan dengan pengamatan perilaku dan pembengkakan, data yang didapat digunakan untuk mengetahui apakah hasil FTIR bersifat universal atau spesifik.antar spesies. Penelitian dilakukan dengan mengambil sampel urine dari dua lutung jawa betina dan dianalisis menggunakan FTIR. Penelitian ini juga mengambil data penunjang yaitu, data perilaku dan data foto genital. Data perilaku yang didapat tidak menunjukkan adanya interaksi seksual antara kedua betina yang menunjukkan sedang estrus. Hasil foto genital yang didapat menunjukkan pembengkakan yang terjadi hanya sampai pada pembengkakan sebagian. Analisis sampel urine menunjukkan E1C teridentifikasi melalui gugus fungsi alkil, aromatik dan hidroksil pada bilangan gelombang 596 cm-1, 698 cm-1, dan 3599 cm-1. PdG teridentifikasi pada gugus fungsi alkil dan aldehid pada bilangan gelombang 1450 cm-1 dan 1699 cm-1.

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Research on technological application of FTIR to detect the fertility period of female javan lutung (Trachypithecus auratus) has been conducted. The aims of this research was to determine the wavenumbers that represented the functional groups of hormone metabolites estrone conjugate (E1C) and pregnanediol-3- glucuronide (PdG) on urine sampels of javan lutung and tied the data with behavioral and swelling observation, the attained data were used to determine whether FTIR results are universal or specific interspecies.

Research was carried out by taking urine samples from two females of javan lutung and measured by using FTIR. This study also use supporting data, which is behavioral data and genital photos. The behavioral data obtained indicate a lack of sexual interactions between the two females, which needed to show that they were estrus.

Resulting genital images obtained, showed that the only swelling that occurs was partial swelling. Analysis of urine samples showed that estrone conjugate (E1C) was identified on functional group of alkyl, aromatic, and hydroxyl at wave numbers 596 cm-1, 698 cm-1, and 3599 cm-1. Pregnanediol-3-glucuronide (PdG) was identified on functional group of alkyl and aldehyde at wave numbers 1450 cm-1 and 1699 cm-1."

"Pada penelitian ini, material pelapis komposit epoksi- ZnO disintesis dan permukaannya dimodifikasi menggunakan asam stearat. Partikel ZnO dipreparasi menggunakan metode yang murah, yaitu penghalusan dengan ball to powder ratio (BPR) 5:1, 10:1, and 15:1 kemudian dilakukan invesitgasi pada struktur kristal, sifat wettability, gugus fungsi, ukuran partikel dan sifat ketahanan korosi setelah dilakukan pencampuran pada epoksi dengan variasi komposisi 0%, 3%, 6% dan 9%. Ukuran partikel terkecil dan terbesar didapatkan pada BPR 5:1 dengan ukuran partikel sebesar 189,3 nm dan 910 nm, secara berurutan. Hasil FTIR menunjukkan bahwa efek hidrofobik didapatkan setelah dilakukan modifikasi pada partikel ZnO akibat gugus fungsi alkil (C-H) dan karboksil asam stearat yang mengganti gugus fungsi hidroksil pada permukaan partikel ZnO. Pengaruh variasi komposisi dan perlakuan modifikasi permukaan mempengaruhi nilai sudut kontak air pada baja yang telah dilapis. Metode Tafel polarisasi dan EIS menunjukkan bahwa penambahan filler maupun modifikasi permukaan mampu menurukan laju korosi. Hasil uji EIS menujukkan nilai Rct dan Rcoat yang bervariasi tetapi memiliki kecenderungan kenaikan ketika terjadi penambahan komposisi filler ZnO dan penambahan modifikasi permukaan. Dari penelitian ini dapat diketahui bahwa komposisi 6% filler maupun perlakuan modifikasi permukaan mampu meningkatkan resistansi korosi melalu mekanisme barrier dan efek hidrofobik. Kata kunci: Elektrokimia korosi, Komposit coating, Modifikasi Permukaan, ZnO

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In this study, the epoxy-ZnO composite coating material was synthesized and the surface using stearic acid. ZnO particles were prepared using an inexpensive method, namely refining with a ball to powder ratio (BPR) of 5:1, 10:1, and 15:1 then investigated on the crystal structure, wettability properties, functional groups, particle size and resistance properties after being carried out. mixing on epoxy with various compositions of 0%, 3%, 6% and 9%. The smallest and largest sizes were found in BPR:1 with particle sizes of 189.3 nm and 910 nm, respectively.

The FTIR results showed that the hydrophobic effect was obtained after modification of the ZnO particles due to the alkyl (C-H) and carboxyl functional groups of stearic acid replacing the hydroxyl functional groups on the surface of the ZnO particles. The effect of variations in composition and surface modification treatment affects the value of the air contact angle on the coated steel. The Tafel polarization method and EIS showed that the addition of filler and surface modification was able to reduce the corrosion rate.

The results of the EIS test showed that the Rct and Rcoat values varied but had a tendency to increase when ZnO filler composition was added and surface modification was added. From this research, it can be seen that the composition of 6% filler and surface modification treatment can increase corrosion resistance through barrier mechanisms and hydrophobic effects.

Keywords: Electrochemical corrosion, Composite coating, Surface Modification, ZnO"

"Korosi yang disebabkan oleh karbondioksida (CO2) pada pipa baja karbon dan peralatan di pengolahan minyak dan gas sangat umum terjadi. CO2 larut dalam air menghasilkan asam karbonat (H2CO3) yang mempunyai sifat yang lebih korosif dibanding asam klorida (HCL) pada pH yang sama. Electrochemical impedance spectroscopy dan linear polarization resistance digunakan untuk mengetahui fenomena proses yang terjadi selama proses adsorbsi inhibitor di permukaan logam. Variasi temperature dan konsentrasi dari inhibitor dilakukan untuk mengetahui kemampuan inhibisi inhibitor dan mekanisme inhibisi. Penelitian ini dilakukan pada baja karbon A106 grB di dalam lingkungan 3% NaCl. Konsentrasi inhibitor bervariasi dari 0,5,15, dan 40 ppm dan dengan variasi temperature di 40 0C dan 90 0C. Pada temperature 40 0C laju korosi menunjukan 213,9 MPY pada lingkungan tanpa penambahan inhibitor , dan akan turun drastis ke 22,4 MPY ketika 5 ppm inhibitor ditambahkan ke lingkungan, dengan effisiensi inhibisi 90%. Penambahan konsentrasi inhibitor sampai 40 ppm meningkatkan effisiensi inhibisi sampai 98%. Penambahan konsentrasi inhibitor berbasis Imidazoline dari dari 0 ppm sampai 5 ppm pada temperature 90 0C dapat menghasilkan penurunan laju korosi yang signifikan yaitu dari 173,3 MPY menjadi 31,67 MPY, dengan effisiensi inhibisi 82%. Dengan penambahan konsentrasi inhibitor sebanyak 40 ppm akan menaikan effisiensi inhibisi sampai 99,99 %. Mekanisme penghambatan laju korosi terjadi sebagai akibat terbentuknya ikatan polar (O-H dan N-H) yang berikatan dengan permukaan logam melalui proses chemisorption.

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Corrosion caused by carbon dioxide (CO2) in carbon steel pipes and equipment in oil and gas processing is very common. Water soluble CO2 produces carbonic acid (H2CO3) which has more corrosive properties than hydrochloric acid (HCL) at the same pH. Electrochemical impedance spectroscopy and linear polarization resistance are used to determine the processes that occur during the adsorbs inhibitor process on the metal surface. Variation of concentration of the inhibitor is conducted to determine the ability of inhibitor inhibition and inhibition mechanism. This research was conducted on A106 gr. B carbon steel in an environment of 3% NaCl. The inhibitor concentration varies from 0,5,15, and 40 ppm at 40 0C. At temperatures of 400C the corrosion rate shows 213.9 MPY in the environment without the addition of inhibitors, and will drop dramatically to 22.4 MPY when 5 ppm inhibitors are added to the environment. Electrochemical Impedance Spectroscopy is used to study inhibition mechanism. Increasing the concentration of Imidazoline based inhibitors from 0 ppm to 5 ppm at 90 0C can produce a significant decrease in corrosion rate from 173.3 MPY to 31.67 MPY, with 82% inhibition efficiency. With the addition of inhibitor concentrations up to 40 ppm will increase inhibition efficiency to 99,99 %. The mechanism of inhibition of corrosion rate occurs as a result of the formation of polar bonds (O-H and N-H) that bind to the metal surface through a chemisorption process."