@article{ChenLoischGrossetal.2018,
  author    = {Chen, Ye and Loisch, Gregor and Gross, Matthias and Jao, Chun-Sung and Krasilnikov, Mikhail and Oppelt, Anne and Osterhoff, Jens and Pohl, Martin and Qian, Houjun and Stephan, Frank and Vafin, Sergei},
  title     = {Generation of quasi continuous-wave electron beams in an L-band normal conducting pulsed RF injector for laboratory astrophysics experiments},
  series = {Nuclear instruments \& methods in physics research : a journal on accelerators, instrumentation and techniques applied to research in nuclear and atomic physics, materials science and related fields in physics ; A, Accelerators, spectrometers, detectors and associated equipment},
  volume    = {903},
  journal   = {Nuclear instruments \& methods in physics research : a journal on accelerators, instrumentation and techniques applied to research in nuclear and atomic physics, materials science and related fields in physics ; A, Accelerators, spectrometers, detectors and associated equipment},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0168-9002},
  doi       = {10.1016/j.nima.2018.06.063},
  pages     = {119 -- 125},
  year      = {2018},
  abstract  = {We report on an approach to produce quasi continuous-wave (cw) electron beams with an average beam current of milliamperes and a mean beam energy of a few MeV in a pulsed RF injector. Potential applications are in the planned laboratory astrophysics programs at DESY. The beam generation is based on field emission from a specially designed metallic field emitter. A quasi cw beam profile is formed over subsequent RF cycles at the resonance frequency of the gun cavity. This is realized by debunching in a cut disk structure accelerating cavity (booster) downstream of the gun. The peak and average beam currents can be tuned in beam dynamics simulations by adjusting operation conditions of the booster cavity. Optimization of the transverse beam size at specific positions (e.g., entrance of the plasma experiment) is performed by applying magnetic focusing fields provided by solenoids along the beam line. In this paper, the design of a microtip field emitter is introduced and characterized in electromagnetic field simulations in the gun cavity. A series of particle tracking simulations are conducted for multi-parametric optimization of the parameters of the produced quasi cw electron beams. The obtained results will be presented and discussed. In addition, measurements of the parasitic field emission (PFE) current (dark current) in the PITZ gun will be exemplarily shown to distinguish its order of magnitude from the produced beam current by the designed field emitter.},
  language  = {en}
}
@article{ChenSongZhaoetal.2018,
  author    = {Chen, Ye and Song, Qilei and Zhao, Junpeng and Gong, Xiangjun and Schlaad, Helmut and Zhang, Guangzhao},
  title     = {Betulin-Constituted multiblock amphiphiles for broad-spectrum protein resistance},
  series = {ACS applied materials \& interfaces},
  volume    = {10},
  journal   = {ACS applied materials \& interfaces},
  number    = {7},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {1944-8244},
  doi       = {10.1021/acsami.7b16255},
  pages     = {6593 -- 6600},
  year      = {2018},
  abstract  = {Multiblock-like amphiphilic polyurethanes constituted by poly(ethylene oxide) and biosourced betulin are designed for antifouling and synthesized by a convenient organocatalytic route comprising tandem chain-growth and step-growth polymerizations. The doping density of betulin (D-B) in the polymer chain structure is readily varied by a mixed-initiator strategy. The spin-coated polymer films exhibit unique nanophase separation and protein resistance behaviors. Higher D-B leads to enhanced surface hydrophobicity and, unexpectedly, improved protein resistance. It is found that the surface holds molecular-level heterogeneity when D-B is substantially high due to restricted phase separation; therefore, broad-spectrum protein resistance is achieved despite considerable surface hydrophobicity. As D-B decreases, the distance between adjacent betulin units increases so that hydrophobic nanodomains are formed, which provide enough landing areas for relatively small-sized proteins to adsorb on the surface.},
  language  = {en}
}