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IntroductionPhotocatalysts utilize light as the driving force in chemical reactions, and have great potential in both the production of solar fuels, e.g. H2 from water splitting, and organic transformations1. To make best use of the Sun’s energy output, a broad visible light absorption profile of the photocatalyst is desired. For heterogeneous semiconductor photocatalysts, the band gap of the semiconductor and potential sensitizers determines the light absorption properties of the catalyst system.Herein, we present the functionalization of the layered semiconductor Sn3S7(trenH)2 (tren = tris[2-aminoethyl]amine) for potential photocatalytic applications. The compound consists of two-dimensional polymeric sheets of [Sn3S72-]n with molecular cations embedded in-between. The material is a violet light absorber with a band gap of approximately 3.0 eV. By partial exchange of the trenH+ ions for organic dyes, the light absorption properties of the large-band gap semiconductor are altered significantly2. The ion exchange is performed in solution, and a number of experimental parameters, e.g. temperature and solvent, have been studied. While solvents such as acetonitrile and acetone retain the crystal structure of Sn3S7(trenH)2, water causes an apparent structural decomposition of the framework. As many photocatalytic reactions are carried out in water, we have studied this amorphization in detail3, to determine whether the local structure and light absorption properties were maintained. X-ray total scattering and pair distribution function (PDF) analysis were used for in-depth characterization of the structural change. Materials and MethodsSn3S7(trenH)2 is synthesized by a solvothermal method. Time-resolved dye intercalation experiments were carried out by dispersing 0.2 g Sn3S7(trenH)2 in a 40 mL dye solution under stirring for 4 h. The dye concentration left in solution was determined by UV-Vis spectroscopy at different time intervals. Different organic dyes, i.e. Methylene Blue (MB) and Safranin T (ST) were tested, and the dye concentration, temperature, and solvent were varied. Optical properties of the dye-functionalized Sn3S7(trenH)2 were examined by Diffuse Reflectance Spectroscopy. The time-dependent water-induced amorphization of Sn3S7(trenH)2 was studied by synchrotron X-ray total scattering. From the scattering data, PDFs were obtained, allowing for the study of the atomic-scale structure of powder samples, which had been dispersed in aqueous solution. Results and DiscussionThe intercalation of MB and ST in Sn3S7(trenH)2 was studied primarily in acetonitrile. At 60 oC and dye concentrations of 230 mg/L, the adsorption of MB is favored over that of ST by a factor of 17, despite a chemical resemblance of the two dyes. This is interpreted as a size-dependent diffusion of the dye molecules through the porous Sn3S7(trenH)2 framework. Temperature also plays an important factor in the dye uptake: Increasing the temperature of the solution from 20 oC to 60 oC increases the MB adsorption from 4.0 mg/g to 33.3 mg/g. The dye intercalation follows pseudo-second order kinetics. Diffuse reflectance spectra clearly demonstrate the increased visible light-absorption of dye-functionalized Sn3S7(trenH)2, cf. Figure 1. Interestingly, the intercalation of MB in water is much more effective than it is in acetonitrile: At similar temperature and dye concentration, the dye uptake from water is almost 10 times greater than from acetonitrile. However, the crystalline Sn3S7(trenH)2 structure is not retained in water, as determined from powder X-ray diffraction patterns. Time-resolved PDFs shows that despite the loss of long-range order, the local order in the Sn3S7(trenH)2 structure does not change during the amorphization in water, cf. Figure 2. Diffraction data revealed a decrease of the interlayer distance between the [Sn3S72-]n sheets, which may be related to leaching of the trenH+ amines from the interior of the material, which results in a disordered stacking of the layers. Even so, the optical properties of the amorphisized Sn3S7(trenH)2 are not altered significantly, and its application as a photocatalyst may still be possible in aqueous solution. Figure 1. Diffuse reflectance spectra of pristine and dye-functionalized Sn3S7(trenH)2. Figure 2. Pair Distribution Functions of Sn3S7(trenH)2 dispersed in H2O for different durations.SignificanceThe present study showcases the possibility of soft chemical functionalization of Sn3S7(trenH)2 by ion exchange for visible light photocatalytic applications. The ion exchange can be performed under mild conditions and is useful for the introduction of molecular dye sensitizers or other functional species. We have shown that the structural transition from crystalline to amorphous, which occurs in water, is not associated with a complete decomposition of the [Sn3S72-]n sheets, but rather a disordering of the layers, and applications of Sn3S7(trenH)2 in aqueous solutions is therefore still possible. References1.Ismail, A. A.; Bahnemann, D. W., Sol. Energy Mater Sol. Cells, 2014, 128, 85-101.2. Hvid, M. S.; Lamagni, P.; Lock, N., Sci. Rep., 2017, 7, 45822. 3. Hvid, M. S. et al., Manuscript in preparation.

Presented at the Zakopane Conference on Nuclear Physics “Extremes of the Nuclear Landscape”, Zakopane, Poland, August 27–September 2, 2012.-- et al., The quasi-elastic scattering angular distribution of the collision 11Be + 64Zn was measured and compared with the elastic scattering angular distribution for its core, the 10Be nucleus on the same target. Optical model and continuum-discretized coupled-channel calculations of the 11Be+64Zn reaction were performed in order to interpret the effect of coupling with the break-up channels on the measured cross-sections.

Siemens has earned three contracts to deliver IONTRIS Particle Therapy accelerator systems* to be operated in Marburg and Kiel, both in Germany, and in Shanghai, China. The accelerator part consists of an injector (7 MeV/u protons and light ions) and a compact synchrotron able to accelerate proton beams up to 250 MeV and carbon ions up to 430 MeV/u. These beams can be slowly extracted and delivered to a choice of fixed-angle horizontal, semi-vertical and vertical beam-ports. An overview of the design will be given and the status of the installation and commissioning work for the first two projects will be shown., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Absolute branching ratios to unbound states in C12 populated in the β decays of N12 and B12 are reported. Clean sources of N12 and B12 were obtained using the isotope separation on-line (ISOL) method. The relative branching ratios to the different populated states were extracted using single-alpha as well as complete kinematics triple-alpha spectra. These two largely independent methods give consistent results. Absolute normalization is achieved via the precisely known absolute branching ratio to the bound 4.44 MeV state in C12. The extracted branching ratios to the unbound states are a factor of three more precise than previous measurements. Branching ratios in the decay of Na20 are also extracted and used to check the results. © 2009 The American Physical Society., Supported by the Academy of Finland (Project No. 44875), by the Spanish Agency CICYT (Nos. FPA2007–62170 and FPA2007–62216), by the European Union Sixth Framework Programme “EURONS” (No. 506065), by the Swedish Research Council, and the Knut and Alice Wallenberg foundation.

4 pages, 4 figures.-- PACS nrs.: 21.10.-k, 21.10.Hw, 25.55.-e, 27.20.+n., We have studied C-12 in full kinematics via the B-10(He-3,pααα) reaction at an energy of 2.45 MeV. In our data we have identified states in C-12 from the ground state up to about 18 MeV, with spins ranging from 0 to 4. Due to the very good resolution, we are able to determine properties of these C-12 resonances, such as their energy, width, and spin. In this contribution preliminary results from the ongoing analysis are presented. Main focus on the precise determination of the breakup spectra for all resonances., This work has been made possible by the CSIC I3P program, and is supported by the European Union under the Sixth framework project EURONS-contract No. 506065.

6 pages, 3 tables, 3 figures.-- Printed version published Mar 30, 2006.-- PACS nrs.: 25.60.Je; 25.45.Hi; 27.20.+n.-- et al., The one-neutron transfer reaction Li-9 + H-2 -> Li-8 + t has been investigated in an inverse kinematics experiment by bombarding a deuterated polypropylene target with a 2.36 MeV/u Li-9 beam from the post-accelerator REX-ISOLDE at CERN. Excitation energies in Li-8 as well as angular distributions of the tritons were obtained and spectroscopic factors deduced., This work has been supported by the European Union Fifth Framework under contract No. HPRI-CT-1999-00018, the BMBF under contract 06 DA 115, GSI under contract DA-RIC, partly by the Spanish CICYT Agency under the project number FPA2002-04181-c04-02 as well as by the ISOLDE collaboration.

5 pags., 2 figs. -- International Symposium on Nuclear Astrophysics - Nuclei in the Cosmos - IX 25-30 June 2006 CERN, We have studied 12C in full kinematics via the 10B( 3He,pααα) reaction at 2.45 MeV. In our data we have identified states in 12C from the ground state up to about 18 MeV, with spins ranging from 0 to 4. Due to the very good resolution, we are able to determine properties of these 12C resonances, such as their energy, width, and spin. In this contribution preliminary results from the ongoing analysis is presented., This work has been made possible by the CSIC I3P program, and is supported by the European Union under the Sixth framework project EURONS-contract number 506065.

5 pages, 2 tables, 3 figures.--PACS nrs.: 23.40.Hc; 27.20.+n., The beta decay of O-13 has been studied at the IGISOL facility of the Jyvaskyla accelerator centre (Finland). By developing a low-energy isotope-separated beam of O-13 and using a modern segmented charged-particle detector array an improved measurement of the delayed proton spectrum was possible. Protons with energy up to more than 12 MeV are measured and the corresponding log(ft) values extracted. A revised decay scheme is constructed. The connection to molecular states and the shell model is discussed., This work was supported by the Academy of Finland under the Finnish Centre of Excellence Programme 2000–2005 (Project No. 44875, Nuclear and Condensed Matter Physics Programme at JYFL), by the European Union Fifth Framework Programme “Improving Human Potential - Access to Research Infrastructure” contract no. HPRI-CT-1999-00044, by the Spanish CICYT Agency under Project number FPA2002-04181-C04-02, and by the EU-RI3 (Integrated Infrastructure Initiative) under contract no 506065.