After fogging process in water injected gas turbine systems

In gas turbine system with after fogging, water droplets are injected after compressor. After fogging could have more significant potential for enhancement of specific power production compared to inlet fogging alone, since a larger water injection rate is possible. Transient analysis of after fogging process is carried out by using a heat and mass transfer modeling on water droplet evaporation. Transient variables such as droplet diameter and air temperature are evaluated as the droplet evaporation proceeds for different values of initial droplet diameter, pressure ratio of compressor, and water injection ratio. The evaporation time for injected droplets are also estimated. Present results show that the evaporation time decreases sensitively with increasing pressure ratio or initial droplet diameter. However, the effect of water injection ratio on evaporation time is relatively insignificant unless water injection ratio is near the critical ratio.     

Improvement of asymmetric viewing angle properties in single-domain fringe-field-switching liquid crystal mode by using parallel-rubbed alignment surfaces

In this paper, we discuss the viewing angle properties of single-domain fringe-field-switching (FFS) liquid crystal (LC) mode aligned by using parallel-rubbed polyimide surfaces. Due to the reduced initial tilting angle distribution in the bulk LC layer under parallel-rubbed surface alignment conditions, the problems of greyscale inversion and off-axis colour shift in the dark state and luminance asymmetry distribution in the low grey level, observed in the conventional single-domain FFS LC mode, can be improved effectively. The viewing angle properties of the proposed structure were analysed by using the Póincare sphere and fringe-field-induced LC distribution.     

Preparation of zwitterionic sulfobetaine end‐functionalized poly(ethylene glycol)‐b‐poly(caprolactone) diblock copolymers and examination of their thermogelling properties

To investigate thermogelling behavior, in this study, we prepared a methoxy poly(ethylene glycol)‐b‐poly(ε‐caprolactone) diblock copolymer (MPC) with varying hydrophobic poly(ε‐caprolactone) (PCL) lengths and an MPC featuring a zwitterionic sulfobetaine (MPC‐ZW) at the chain end of the PCL segment. The terminal zwitterionic sulfobetaine was stoichiometrically modified to the terminal MPC diblock copolymer. The introduction of the zwitterionic end group lowered the crystallization enthalpies of the PCL block segments and increased the solubility of the diblock copolymer. The MPC and MPC‐ZW copolymers thus obtained formed translucent emulsions at room temperature when prepared as 20 wt %. When the temperature was increased above room temperature, MPC and MPC‐ZW exhibited a sol‐to‐gel phase transition. The phase transition and the gelation time of MPC and MPC‐ZW were affected by the length of the hydrophobic segments and the zwitterionic end group. Furthermore, introducing a zwitterionic end group into the PCL segment altered the onset temperature of gelation. Thus, we conclude that zwitterionic end groups introduced into PCL segments of distinct lengths could serve as key determinants in the thermogelling behavior of copolymers. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2185–2191     

Implementing 2→<Emphasis Type="Italic">M</Emphasis> Phase-covariant Cloning in Spin Networks

We propose a scheme to implement 2→M phase-covariant quantum cloning machine by using a M+2 spin star network in which the two central spins interact with the M outer spins respectively. The effect of the magnetic field on the fidelity of the cloning is also investigated. By applying an external magnetic field on the spin system, the fidelity of the cloning machine can be largely improved.     

Influence of crystalline peripheral chain length on the solid‐state assemblies of amphiphilic dendrons

We prepared third‐generation amphiphilic dendrons 3‐14 and 3‐18 consisting of a hydrophilic aliphatic polyether dendritic core and either tetradecyl or octadecyl peripheries, respectively. Their solid‐state self‐assembly behavior was investigated by comparison with 3‐22 having the same dendritic core and longer docosyl peripheries. In marked contrast to the lamellar assembly of 3‐22 , small‐angle X‐ray analysis suggested that 3‐14 and 3‐18 show oblique columnar structures with presumably elliptical cross sections. The observed results can be rationalized by dendron shape anisotropy, which is strongly associated with the degree of crystallization as a function of alkyl chain length. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4988–4994, 2007