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Abstract Lignin is considered as a renewable and sustainable resource for producing value-added aromatic chemicals and functional carbon materials. Herein, we develop a one-step catalyst-free depolymerization strategy to convert lignin into aryl monomers and carbon nanospheres simultaneously. Importantly, microwave-assisted depolymerization (MAD) in conjunction with dichloromethane (CH2Cl2) vapors is developed. The total mass yield of guaiacols reached the highest amount of 225.1 mg/g at 600 °C, and the highest yields of phenols (49.0 mg/g) and aromatic hydrocarbons (155.1 mg/g) were obtained at 700 °C. Hydrogen radicals and hydrogen chloride (HCl) are in-situ formed from CH2Cl2, significantly decreasing the activation barrier and reforming pyrolysis vapors to promote the formation of aryl monomers. Interestingly, uniform carbon nanospheres with an average size of 140 nm were produced as co-products at 700 °C. The microwave “hot-spots”, allied with the continuous surface erosion and the decrease in surface energy of lignin-derived carbon precursors by CH2Cl2 vapor, can be considered the driving force for the ultimate formation of carbon nanospheres. The CH2Cl2/MAD system produces aryl monomers (26.8 wt% yield) and carbon nanospheres (36.6 wt% yield) at 700 °C. We provide a facile, intriguing and scalable approach to convert lignin to valuable aryl monomers and sustainable carbon materials that can be applied in the chemistry, energy and environmental fields.

The ATLAS Inner Detector is a composite tracking system consisting of silicon pixels, silicon strips and straw tubes in a 2 T magnetic field. Its installation was completed in August 2008 and the detector took part in data- taking with single LHC beams and cosmic rays. The initial detector operation, hardware commissioning and in-situ calibrations are described. Tracking performance has been measured with 7.6 million cosmic-ray events, collected using a tracking trigger and reconstructed with modular pattern-recognition and fitting software. The intrinsic hit efficiency and tracking trigger efficiencies are close to 100%. Lorentz angle measurements for both electrons and holes, specific energy-loss calibration and transition radiation turn-on measurements have been performed. Different alignment techniques have been used to reconstruct the detector geometry. After the initial alignment, a transverse impact parameter resolution of 22.1+/-0.9 ��m and a relative momentum resolution ��p/p = (4.83+/-0.16) \times 10-4 GeV-1 \times pT have been measured for high momentum tracks. 34 pages, 25 figures

The authors have performed high resolution angle resolved photoemission spectroscopy (HRARPES) on samples of K{sub 0.3}MoO{sub 3}, TiTe{sub 2} and Ti{sub 1+x}S{sub 2}, materials which are a quasi-one dimensional metal, a quasi-two dimensional metal, and a quasi two-dimensional metal (x > 0) or semi-conductor (x = 0), respectively. They are interested in looking at these samples using HRARPES as part of the general program to assess the use of photoemission to determine whether a particular system behaves like a Fermi liquid or not. For one dimensional metallic systems, angle integrated photoemission studies to date, e.g., reveal that, contrary to higher dimensional cases where a sharp Fermi cutoff is seen at the Fermi level, there is very little weight at the Fermi level. It seems that there is yet no agreement why this is so. They think that detailed information they get from HRARPES will help them answer this question. The system Ti{sub 1+x}S{sub 2} gives the possibility to control the filling of the Ti 3d conduction band by adjusting x. Interest in this system lies in measuring the spectra and the line shape of samples with different stoichiometry and correlating the spectroscopic data with the corresponding transport data.