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[Display omitted] • ML model was developed in Python using multiple linear regression algorithm. • The ML model predicted energy consumption through correlations for energy uses. • 3.9 * 106 dollars of annual saving was reached in ammonia plant operating cost. • CO 2 emissions were reduced by 4.7 ton/ hr due to energy efficiency adjustment. • Benchmark methodology is used to identify energy saving options in ammonia plants. Energy efficiency is becoming increasingly important nowadays due to the need for energy conservation and environmental sustainability. An existing ammonia plant was simulated using Aspen Hysys software, the simulated plant was used to produce large volumes of data to train and test our machine-learning model. In this work a benchmark methodology is proposed through machine-learning (ML) techniques to identify patterns and anomalies in energy consumption. Our ML model was developed in Python programming language using a multiple linear regression algorithm. Microsoft Power BI was used to build interactive visualizations to illustrate insights to users. The ML model was able to predict energy consumption by developing equations that relate the energy consumption and the operating variables for each significant energy user in the ammonia plant. In this study, actual versus optimum energy consumption was analyzed for four ammonia production plants. The ML model identified the ammonia plant operating costs and potential savings by adjusting operating conditions. An annual saving of up to 3.9 million dollars was reached in one of the ammonia production plants operating costs. A reduction in carbon dioxide emissions of up to 4.7 ton per hour was achieved due to energy efficiency adjustment. [ABSTRACT FROM AUTHOR]

We examined the chemical and local structural properties of oxidized TiN/ZnS and TiN/ZnO thin films using X-ray absorption spectroscopy (XAS). The composite films were oxidized by post-deposition annealing (PDA) under various oxygen partial pressures (P(O 2)). The results of the X-ray absorption near-edge structure (XANES) analyses showed that the S and N vaporized, and a zinc titanate (ZnTiO 3)-like phase formed when annealed under the oxygen ambiance. An ab initio XANES simulation as well as the extended X-ray absorption fine structure (EXAFS) analysis further resolved the local structures of ZnTiO 3 -like phase into high symmetry structures such as ilmenite-like or perovskite-like local structure; for instance, the local structure of TiN/ZnS films annealed with P(O 2) = 2 Torr could be described as a mixture of 50% ilmenite ZnTiO 3 + 30% perovskite ZnTiO 3 + 20% wurtzite ZnO local structures. The formation of ZnTiO 3 -like local structure is also subject to the temperature during the PDA or the choice of bottom layers (ZnS or ZnO). The temperature of the TiN/ZnS-to-ZnTiO 3 local structural phase transformation, was estimated to be 500–600 °C at P(O 2) = 2 Torr, and ZnO as bottom layer apparently expedited such local structural evolution by supplying oxygen to TiN. Unlabelled Image • Local structures of ultrathin TiN/ZnS films were identified by soft and hard XASs. • After annealing under oxygen ambiance, the films became oxidized to form titanates. • The local structures likely consist of ilmenite- and perovskite-like local structures. [ABSTRACT FROM AUTHOR]

Abstract: We present the results from investigations of the nonlinear refractive index and nonlinear absorption coefficient of tris(acetylacetonato)manganese(III) solution, using Z-scan technique with a low-power continuous-wave laser at 514nm. We demonstrate that the light-induced nonlinear refractive index variation leads to strong self-focusing and self-defocusing. A pump and probe technique was used to investigate the cause of nonlinearity. Furthermore, the nonlinear absorption effect was utilized to demonstrate all optical switching. [Copyright &y& Elsevier]

Abstract: Thin Bis-(dimethylglyoximato)nickel(II) [Ni(DMG)2] films of amorphous and crystalline structures were prepared by vacuum deposition on Si (P) substrates. The films were characterised by X-ray fluorescence and X-ray diffraction. The constructed Al/Ni(DMG)2/Si(P) metal-insulator-semiconductor devices were characterised by the measurement of the gate-voltage dependence of their capacitance and ac conductance, from which the surface states density Dit of insulator/semiconductor interface and the density of the fixed charges in the oxide were determined. The ac electrical conduction and dielectric properties of the Ni(DMG)2-Silicon structure were studied at room temperature. The data of the ac measurements of the annealed films follow the correlated barrier-hopping CBH mode, from which the fundamental absorption bandgap, the minimum hopping distance, and other parameters of the model were determined. [Copyright &y& Elsevier]