Recent results of the searches for Supersymmetry in final states with one or two leptons at CMS are presented. Many Supersymmetry scenarios, including the Constrained Minimal Supersymmetric extension of the Standard Model (CMSSM), predict a substantial amount of events containing leptons, while the largest fraction of Standard Model background events -which are QCD interactions -gets strongly reduced by requiring isolated leptons. The analyzed data was taken in 2011 and corresponds to an integrated luminosity of approximately L = 1 fb −1 . The center-of-mass energy of the pp collisions was √ s = 7 TeV.

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Recently, more and more attention is paid on applications of molten chlorides in concentrated solar power (CSP) plants as high-temperature thermal energy storage (TES) and heat transfer fluid (HTF) materials due to their high thermal stability limits and low prices, compared to the commercial TES/HTF materials in CSP-nitrate salt mixtures. A higher TES/HTF operating temperature leads to higher efficiency of thermal to electrical energy conversion of the power block in CSP, however causes additional challenges, particularly increased corrosiveness of metallic alloys used as containers and structural materials. Thus, it is essential to study corrosion behaviors and mechanisms of metallic alloys in molten chlorides at operating temperatures (500-800°C) for realizing the commercial application of molten chlorides in CSP. The results of studies on hot corrosion of metallic alloys in molten chlorides are reviewed to understand their corrosion behaviors and mechanisms under various conditions (e.g., temperature, atmosphere). Emphasis has also been given on salt purification to reduce corrosive impurities in molten chlorides and development of electrochemical techniques to in-situ monitor corrosive impurities in molten chlorides, in order to efficiently control corrosion rates of metallic alloys in molten chlorides to meet the requirements of industrial applications.

SUMMARYThis paper is focussed on thermal storage technologies using phase change materials (PCMs) in the temperature range of 120-3008C for solar thermal power generation and high temperature process heat. As the state-of-the-art reference system a steam accumulator is described, which typically has a volume-specific thermal energy density of 20-30 kWh m À3 . Regarding efficiency, a fundamental demand on thermal storage is the minimization of temperature differences between working fluid and storage medium. This requires isothermal storage systems for processes using water/steam. An obvious solution is, therefore, the application of PCMs.The selection of the PCMs depends strongly on the operation conditions of the respective application. At present, the main emphasis is directed to alkali metal nitrates and nitrites and their mixtures. For example, the eutectic mixture of the binary system KNO 3 -NaNO 3 has been identified as an excellent system to be used for processes using saturated steam at around 25 bar. At around 5 bar the ternary system KNO 3 -NaNO 2 -NaNO 3 , commonly used as heat transfer fluid, can also be used as a PCM. To overcome the low thermal conductivity of the salt systems, approaches of increased surfaces area and increased thermal conductivity using expanded graphite (EG) have been investigated. Using EG/PCM composites, the effective thermal conductivity can be increased from below 0.5 to 3-20 W (mK) À1. Three design concepts have been developed. In the macro-encapsulated design, the PCM is enclosed in metal tubes, giving a short distance for heat transfer and increasing the heat transfer area. In the second design, the heat exchanger tubes are embedded in EG/PCM-composite storage material. The third design option uses graphite foils arranged perpendicularly onto the heat exchanger tubes and a suitable salt system filled in between. The upgrade of existing steam accumulators using these PCM concepts is also proposed.

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Molten chloride salts are promising advanced high-temperature (400-800°C) thermal energy storage (TES) and heat transfer fluid (HTF) materials in next generation concentrated solar power (CSP) plants for higher energy conversion efficiencies. However, severe corrosion of structural materials in contact with molten chloride salts is one of the most critical challenges limiting their applications at elevated temperatures. In this work, two corrosion mitigation strategies are investigated to alleviate the hot corrosion of structural materials in molten chloride salts: (1) adding corrosion inhibitor and (2) using a Fe-Cr-Al alloy with a protective alumina layer on the surface after pre-oxidation. Three commercial high temperature Fe-Cr-Ni alloys (SS 310, Incoloy ® 800 H and Hastelloy ® C-276) were exposed to molten MgCl 2 -NaCl-KCl (60-20-20 mole.-%) mixed salts with 1 wt.-% Mg as corrosion inhibitor, for 500h at 700°C under inert atmosphere. By addition of the Mg inhibitor, the corrosion rates of the studied alloys were found to be significantly reduced, more precisely by ~83 % for SS 310, ~70 % for In 800 H and ~94 % for Ha C-276 compared with the exposure tests without Mg addition. To assess the second mitigation strategy two pre-oxidized alumina forming Fe-Cr-Al alloys were exposed to the same molten chloride salts without Mg corrosion inhibitor under the same conditions. It is observed that the adherent alumina scales can effectively inhibit the dissolution of Cr and Fe and the bulk penetration of corrosive impurities. Overall, both strategies offer enormous potential for enhancing the expected lifetime of commercial alloys in molten chloride salts. Highlights  By Mg-addition the corrosion rates of alloy SS 310, In 800 H and Ha C-276 are significantly reduced. 2  Adding Mg inhibitor not only mitigates the corrosion caused by impurities, but also promotes the formation of protective MgO layer on metal surfaces.  The corrosion mitigation mechanism of Fe-Cr-Ni based alloys in molten chloride salts by adding Mg is discussed. Pre-oxidized alumina forming Fe-Cr-Al alloys show promising corrosion resistance and stability in molten chloride salts at 700°C for 500h exposure.

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