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"Korosi merupakan peristiwa yang kerap terjadi pada pipa di industri perminyakan yang ditandai dengan penurunan kualitas akibat reaksi kimia pada logam sehingga dapat mengakibatkan kerugian bagi industri tersebut. Oleh karena itu, untuk memperlambat laju korosi dibutuhkan suatu inhibitor korosi. Inhibitor korosi organik lebih banyak digunakan dibanding dengan inhibitor korosi anorganik karena bersifat nontoksik dan lebih efektif. Salah satu dari inhibitor korosi organik yang banyak digunakan adalah imidazolin. Imidazolin merupakan senyawa organik heterosiklik dengan 2 unsur nitrogen, rantai panjang hidrokarbon, dan rantai sisi dengan gugus fungsi aktif . Pada penelitian ini senyawa turunan imidazolin telah disintesis dari trietilentetramina (TETA) dengan variasi asam lemak, yaitu asam stearat (AS) proanalisis dan teknis, serta asam oleat (AO) pro analisis dan teknis dengan menggunakan kondisi optimum pada penelitian sebelumnya. Produk yang diperoleh kemudian dipisahkan dengan metode ekstraksi pelarut dan diidentifikasi menggunakan kromatografi lapis tipis (KLT). Terhadap masing-masing hasil reaksi juga telah dikarakterisasi menggunakan instrumen UV-Vis, FTIR, dan LC-MS/MS. Uji aktivitas terhadap inhibisi korosi pada baja karbon dalam larutan 1% NaCl dilakukan untuk masing-masing produk untuk memperoleh nilai persen efisiensi inhibisi (%EI). Nilai persen efisiensi inhibisi untuk TETA-AO murni; TETA-AO teknis; TETA-AS murni; TETA-AS teknis; dan imidazolin komersil terbesar terdapat pada konsentrasi 500 ppm dengan %EI berturut-turut 87,95%; 83,26%; 84,43%; 75,42%; dan 84,41%. TETA-AO murni memiliki %EI terbesar sehingga dilanjutkan untuk penentuan data kinetika dan termodinamika dari reaksi sintesis senyawa imidazolin tersebut dengan menggunakan instrumen UV-Vis dan titrasi melalui penentuan angka asam. Data kinetika dan termodinamika yang diperoleh diharapkan dapat diaplikasikan dan dikembangkan untuk TETA-AO teknis pada sintesis skala besar senyawa inhibitor korosi turunan imidazolin di dunia industri karena harganya lebih ekonomis. Melalui hasil penentuan angka asam didapatkan data jika reaksi merupakan pseudo-orde 1, energi aktivasi sebesar 36.96 kJ/mol, faktor frekuensi sebesar 112,62 menit. Data termodinamika yang didapatkan meliputi energi entalpi sebesar 33,65 kJ/mol, entropi sebesar -0,2504 kJ/mol.K, dan energi gibbs untuk suhu 110, 120, 130, dan 140^o C berturut-turut sebesar 129,55 kJ/mol; 132,06 kJ/mol; 134,56 kJ/mol; dan 1237,07 kJ/mol.Corrosion is an event that often occurs in the pipeline in the oil industry which is characterized by a decrease in quality due to chemical reactions on the metal so that it can cause harm to the industry. Therefore, to slow down the corrosion rate a corrosion inhibitor is needed. Organic corrosion inhibitors are more widely used than inorganic corrosion inhibitors because they are non-toxic and more effective. One of the most widely used organic corrosion inhibitors is imidazoline. Imidazoline is a heterocyclic organic compound with 2 nitrogen elements, a long chain of hydrocarbons, and a side chain with an active function group (pendant). In this study, imidazoline derivatives had been synthesized from triethylenetetramine (TETA) ) with a variety of fatty acids, namely stearic acid (SA) and oleic acid (OA) both in pro analysis and in technical grade using Microwave Assisted Organic Synthesis (MAOS) with optimum condition followed the previous study. The obtained products then were separated by a solvent extraction method and identified using thin-layer chromatography (TLC). Moreover, the products had also been characterized using FTIR, UV-Vis spectral data, and LC-MS/MS. The activity of corrosion inhibition on carbon steel in a solution of 1% NaCl was carried out for all products to obtain inhibition efficiency (% IE). %IE for TETA-OA pro analysis; TETA-OA technical; TETA-SA pro analysis; TETA-SA technical; and the commercial imidazoline at a concentration of 500 ppm were 87.95%; 83.26%; 84.43%; 75.42%; and 84.41%, respectively. It can be concluded that triethylenetetramine-derived imidazoline can be used as a corrosion inhibitor towards carbon steel. TETA-OA pro analysis has the largest %IE so that it will be continued for the determination of kinetic and thermodynamic data from the synthesis reaction of the imidazoline compound by using the UV-Vis instrument and titration through the determination of acid numbers. The kinetic and thermodynamic data obtained are expected to be applied to the synthesis of large scale imidazoline derivative corrosion inhibitor compounds in the industrial world. Through the results of the determination of acid numbers obtained data if the reaction is pseudo-order 1, the activation energy is 36.96 kJ/mol, and pre-exponential factors are 112.62  min^-1. For thermodynamic data obtained enthalpy energy of 33.65 kJ/mol; entropy equal to -0,2504 kJ/mol.K, and Gibbs energy for 110, 120, 130, dan 140^o C are 129.55 kJ/mol; 132.06 kJ/mol; 134.56 kJ/mol;  137.07 kJ/mol, respectively.

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"This is the second volume of three books devoted to Mechanics. In this book, dynamical and advanced mechanics problems are stated, illustrated, and discussed, including a few novel concepts."

"This book presents a new approach to learning the dynamics of particles and rigid bodies at an intermediate to advanced level. There are three distinguishing features of this approach. First, the primary emphasis is to obtain the equations of motion of dynamical systems and to solve them numerically. As a consequence, most of the analytical exercises and homework found in traditional dynamics texts written at this level are replaced by MATLAB®-based simulations. Second, extensive use is made of matrices. Matrices are essential to define the important role that constraints have on the behavior of dynamical systems. Matrices are also key elements in many of the software tools that engineers use to solve more complex and practical dynamics problems, such as in the multi-body codes used for analyzing mechanical, aerospace, and biomechanics systems. The third and feature is the use of a combination of Newton-Euler and Lagrangian (analytical mechanics) treatments for solving dynamics problems. Rather than discussing these two treatments separately, Engineering Dynamics 2.0 uses a geometrical approach that ties these two treatments together, leading to a more transparent description of difficult concepts such as "virtual" displacements."