Proteins and nucleic acids are sequence-regulated macromolecules with various properties originating from their perfectly sequenced primary structures. However, the sequence regulation of synthetic polymers, particularly vinyl polymers, has not been achieved and is one of the ultimate goals in polymer chemistry. In this study, we report a strategy to obtain sequenceregulated vinyl copolymers consisting of styrene, acrylate and vinyl chloride units using metalcatalysed step-growth radical polyaddition of designed monomers prepared from common vinyl monomer building blocks. Unprecedented ABCC-sequence-regulated copolymers with perfect vinyl chloride -styrene -acrylate -acrylate sequences were obtained by copper-catalysed step-growth radical polymerization of designed monomers possessing unconjugated C = C and reactive C -Cl bonds. This strategy may open a new route in the study of sequence-regulated synthetic polymers.

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Following the news that the radiation level in Iitate Village, located 25-45 km from the Fukushima Daiichi Nuclear Power Plant, was seriously increased, an urgent field survey was carried out on 28 and 29 March 2011. Radiation levels at 130 locations were measured inside a van that traveled throughout the village using a CsI pocket survey meter and an ionization chamber. Soil samples were also taken at five locations and submitted to gamma ray analysis using a Ge detector. A radiation exposure rate of more than 20 μSv h was observed in the southern part of Iitate Village. Volatile radionuclides such as iodine and cesium were found to be the main components of radioactive contamination. A trace amount of plutonium isotopes originating from the accident was also confirmed in several soil samples, the level of which was less than the global fallout. Based on the measured density of radionuclides at the highest contamination location during the present survey, an exposure rate of about 200 μGy h at 1 m above the ground was estimated at the time of the radioactive deposition on March 15. At this location, the cumulative exposure would reach 50 mGy in the middle of May 2011.

We demonstrate the successful fabrication of an almost defect free Si͑001͒ surface by refining the standard annealing and flashing surface preparation method. On any desired samples, we can routinely fabricate a surface with defect densities lower than 0.1%, significantly reducing the defect density compared to surfaces fabricated by standard methodology.