Influence of APS bias voltage on properties of HfO_2 and SiO_2 single layer deposited by plasma ion-assisted deposition

HfO2 and SiO2 single layer is deposited on glass substrate with plasma ion assistance provided by Leybold advanced plasma source (APS). The deposition is performed with a bias voltage in the range of 70-130 V for HfO2, and 70-170 V for SiO2. Optical, structural, mechanical properties, as well as absorption and laser induced damage threshold at 1064 nm of HfO2 and SiO2 single layer deposited with the plasma ion assistance are systematically investigated. With the increase of APS bias voltage, coatings with higher refractive index, reduced surface roughness, and higher laser-induced damage threshold (LIDT) are obtained, and no significant change of the absorption at 1064 nm is observed. For HfO2, a bias voltage can be identified to achieve coatings without any stress. However, too-high bias voltage can cause the increase of surface roughness and stress, and decrease the LIDT. The bias voltage can be properly identified to achieve coatings with desired properties.     

1047-nm all-solid-state laser based on Nd:LuLF

A compact all-solid-state continuous-wave (CW) laser at 1047 nm is developed based on Nd:LuLF, which is grown through the Czochralski technique. From the laser system, 1.3-W laser can be obtained, which corresponds to the slope efficiencies of 20.1% and 49.5% with respect to the incident and absorbed pump powers, respectively. To the best of our knowledge, this is the highest power level achieved at 1047 nm based on the Nd:LuLF crystal.     

Unicity of Enrichment over Cat or Gpd

Enrichment of ordinary monads over Cat or Gpd is fundamental to Max Kelly’s unified theory of coherence for categories with structure. So here, we investigate existence and unicity of enrichments of ordinary functors, natural transformations, and hence also monads, over Cat and Gpd. We show that every ordinary natural transformation between 2-functors whose domain 2-category has either tensors or cotensors with the arrow category is 2-natural. We use that to prove that an ordinary monad, or endofunctor, on such a 2-category has at most one enrichment over Cat or Gpd. We also describe a monad on Cat that has no enrichment. So enrichment over Cat is a non-trivial property of a monad rather than a structure that is additional to it. Finally, we present an example, due to Kelly, of V other than Cat or Gpd and an ordinary monad for which more than one enrichment over V exists, showing that our main theorem is specific to Cat and Gpd.     

超高负荷跨音速涡轮的设计与性能分析研究

为了通过增加涡轮级负荷减少级数给涡轮减重,本文开展了单级压比为5的高负荷跨音速涡轮的基本分析和初步设计。研究结果表明,基于常规涡轮设计体系,辅以超高负荷涡轮参数选取以及跨音速涡轮叶片造型方法,进行超高负荷跨音速涡轮的设计,能取得满意效果。在设计工况下,涡轮的级效率达90.3%,且变工况性能相对较好,所设计涡轮基本能达到...     

Transverse radius dependence for transverse velocity and elliptic flow in intermediate energy HIC

The mean transverse velocity and elliptic flow of light fragments (A ≤ 2) as a function of transverse radius are studied for 25 MeV/nucleon ⁶⁴Cu+⁶⁴Cu collisions with impact parameters 3--5 fm by the isospin-dependent quantum molecular dynamics model. By comparison between the in-plane and the out-of-plane transverse velocities, the elliptic flow dependence on the transverse radius can be understood qualitatively, and variation of the direction of the resultant force on the fragments can be investigated qualitatively.     

On the Banach space isomorphism type of AF C*-algebras and their triangular subalgebras

It is shown that all the approximately finite dimensional C^*-algebras which are not of Type I are isomorphic as Banach spaces. This generalizes the matroid case given previously by Arazy. Analogous results are obtained for various families of triangular subalgebras of AF C^*-algebras. In addition the classification of various continua of Type I AF C^*-algebras is discussed.