The Rochow process is the most common technology used to prepare organosilicon compounds on an industrial scale, and yet the mechanism is still not well understood. It involves the reaction of methyl chloride (CH3Cl) with silicon, catalyzed by copper. To understand the elementary steps of the reaction involved, we studied the molecular adsorption of CH3Cl/Cu­(410) at 100 K and its complete desorption at higher temperatures, 100 K < T D < 200 K. Temperature-programmed desorption (TPD) spectra show two CH3Cl desorption peaks. We attribute the low temperature TPD peak (T D ≈ 120 K) to CH3Cl desorbing from both step-edges and terraces and the high temperature TPD peak (T D ≈ 160 K) to CH3Cl desorbing from the step-edges. Infrared reflection–absorption spectra (IRAS) indicate that at low CH3Cl coverage (Θ = 0.06 ML), CH3Cl adsorbs with its molecular axis (Cl–C bond) aligned either parallel or perpendicular to [001]. At high CH3Cl coverage (Θ ≥ 0.09 ML), CH3Cl adsorbs with its molecular axis aligned perpendicular to [001].

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A theoretical study based on density functional theory for H 2 O dissociation on the metal surface of Pt(111) alloyed simultaneously with Ru and Mo was performed. The determination of the minimum energy path using the climbing image nudged elastic band (CI-NEB) method shows that the dissociation reaction of H 2 O with this catalyst requires almost no energy cost. This dissociation reaction is not only kinetically favored but also almost thermodynamically neutral and somewhat exothermic. The electronic structure analysis showed that much more charge was released in Mo and was used to bind the adsorbed hydroxyl (OH ad ). Further analyses of the density of states (DOS) showed that the large number of orbitals that overlap when OH binds to Mo are responsible for the stabilization of the OH-surface bond. The stability of the OH ad fragment on the surface is believed to be a descriptor for the dissociation of H 2 O with an almost spontaneous process.

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Sambungan FSSW dengan material yang berbeda banyak digunakan pada kendaraan. Namun, masalah muncul ketika material tersebut tidak tersambung dengan sempurna. Penggunaan interlayer Zn mampu meningkatkan kemampuan sambungan. Variasi penggunaan dwell time dan diameter shoulder digunakan untuk memperjelas peranan interlayer electroplating Zn. Pengujian tarik geser yang telah dilakukan membuktikan bahwa penggunaan interlayer electroplating Zn memiliki kemampuan sambungan yang lebih baik. Nilai maksimal pengujian tarik geser sebesar 3.8 kN. Nilai maksimal sambungan tanpa interlayer elektroplating Zn 2.5 kN. Pengujian kekerasan menunjukkan nilai yang lebih besar 63 HV dari pada sambungan tanpa menggunakan interlayer elektroplating Zn.