R&D of CEPC injector linac

The CEPC includes a main ring and an injector. The injector consists of a booster and a linac. In order to meet the requirements of the booster, the baseline design of the linac is a 10 GeV electron and positron linac. Two alternative linac designs have also been introduced in this paper. For the linac baseline design, one-bunch-per-pulse is adopted. A 1.1 GeV damping ring is used to reduce the transverse emittance of positron beam. The main RF system of the linac adopts normal conducting S-band structure. Some key technologies of linac are development. The S-band structure and pulse compressor have been researched and studied. In the damping ring, two cavities used to provide 2 MV voltage. The preliminary cavity design has finished.

Accelerator Design for 1.3 MW Beam Power Operation of the J-PARC Main Ring

The J-PARC Main Ring (MR) has supplied the high-intensity proton beam for the T2K long-baseline neutrino experiment since 2010. The present beam power is 510 kW and the total number of protons on the target reaches 3.64 × 1021. To observe CP violation in the lepton sector with high accuracy, more protons need to be delivered to the T2K target. The project to upgrade the beam power to 1.3 MW started as a mid-term plan of the MR. In parallel to preparing a full technical design report, the technical designs of hardware upgrades using new technologies and all accelerator components that are necessary to deliver the 1.3-MW beam power are summarized and consolidated in this short paper. Further, this paper includes beam dynamics studies and simulation results for handling 3.3 × 1014 protons per pulse (ppp) without significant beam loss in the ring and transport lines. The Hyper-Kamiokande (HK) project has recently been approved, and construction has started; the MR upgrade and HK project will work together efficiently to study the CP violation.

Eldvatn bridge – Iceland´s first network arch bridge

<p>Following an enormous flooding event in the Skaftá glacial river in the south of Iceland in 2015, which severely damaged the existing bridge, a new network arch bridge has been designed, constructed and opened in 2019 to restore a much-needed road connection across the river adjoining the Main Ring Road [1]. The 79 m long bridge, designed by EFLA in cooperation with the Icelandic Road and Coastal Administration, is the first network arch bridge in Iceland.</p><p><br clear="none"/></p>

Structure–activity relationships of furanones, dihydropyrrolones and thiophenones as potential quorum sensing inhibitors

Since their initial isolation from the marine alga Delisea pulchra, bromofuranones have been investigated as potential inhibitors of quorum sensing (QS) in various bacterial strains. QS is an important mechanism by which bacteria co-ordinate their molecular response to the environment. QS is intrinsically linked to bacterial antibiotic resistance. Inspired by nature, chemists have developed a wide variety of synthetic analogs in an effort to elucidate the structure–activity relationships of these compounds, and to ultimately develop novel antimicrobial agents. In this work, we describe advances in this field while paying particular attention to apparent structure–activity relationships. This review is organized according to the main ring systems under investigation, namely furanones, dihydropyrrolones and thiophenones.

Polarization issues in circular electron–positron super-colliders

We study a possibility of obtaining transversely polarized electron/positron beams in the CEPC collider. Also, original results are presented for another project, the FCCee collider, which allows us to identify some features and differences of these similar machines. Important is the comparison of the data obtained with the expected and measured polarizations at LEP. In estimation of the depolarizing effect of field errors, in addition to the usual nonresonant spin diffusion, an attempt was made to take into account the resonant diffusion, which is due to a large spin tune spread. We consider a possibility to obtain polarization by accelerating polarized particles in the CEPC booster and then injecting them into the main ring. This option can be crucial for obtaining longitudinal polarization. We propose a scheme in which long-term preservation of such polarization is possible.