Airconditioning system notably contributes to global warming owing to the huge amount of energy consumption. Moreover, this system uses HFC based refrigerants, which have high global warming potential (GWP). This work investigates the direct and indirect impacts of GWP for commercial and residential airconditioning systems considering the three widely used HFC based refrigerants. The warming impacts are assessed in terms of cooling load, coefficient of performance (COP), evaporation temperature, and condensation temperature for three different locations in Japan. The indirect emission of the airconditioning systems (commercial and residential) for different major cities of Japan is estimated in terms of energy demand and hours of operation. The results of this work indicate that the HFC based refrigerants such as R134a and R32 have lower warming impact compared to that of R410A refrigerant. Furthermore, the economic loss due to refrigerant leakage is also assessed.

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We report the magnetic dead layer at the interfaces between Fe and Si(111) surfaces. We prepared two ultrathin iron-silicides, c(8×4) prepared at 900 K and p(2×2) at 700 K, and clean reconstructed 7×7 surface for the silicon templates. By using magneto-optical Kerr effect, we found that at room temperature the ferromagnetic order appears at 5.5 ML, 8.2 ML, and 10.9 ML for Fe/c(8×4) silicide, Fe/p(2×2) silicide, and Fe/Si(111)-7×7 surface, respectively. From the thickness dependent magnetization measurements, we decided the magnetic dead layer for Fe/c(8×4) silicide, Fe/p(2×2) silicide, and Fe/Si(111)-7×7 to be 3.0 ML, 5.0 ML, and 7.5 ML, respectively. Our results indicate that the c(8×4) iron silicide surface prevents further silicide formation more effectively than the p(2×2) silicide and Si(111)-7×7 surface.

Magnetic and chemical properties of ultrathin Fe films on molybdenum disulfide (MoS2) are investigated using magneto‐optic Kerr effect (MOKE) and X‐ray photoemission spectroscopy (XPS). A magnetization hysteresis loop is found after nominal 10 Å of Fe deposition on MoS2 at room temperature. The thickness‐dependent MOKE measurement evaluates that the magnetic dead layer (MDL) exists up to ≈2 Å of Fe on MoS2 due to the interaction between Fe and MoS2. XPS shows small peak shifting for Mo 3d and S 2p peaks toward lower binding energies with initial Fe deposition, indicating the modification of surface band bending. Fe 2p peaks for lower thickness of Fe are significantly broader than those for higher thickness, which is attributed to the coexistence of metallic and ionic Fe in the film. The presence of ionic Fe, localized at the interface, indicates strong interactions between Fe and MoS2, and the existence of chemical bonding at the interface is corroborated with the formation of MDL.