Poly(ethylene glycol) (PEG)-based films, nanotubes, and nanotube arrays were successfully made using layer-by-layer (LbL) assembly ion-containing PEO derivatives on porous templates and planar substrates. PEG nanotubes are challenging to produce because PEG dissolves into solutions and solvents used during nanotube processing, but our techniques circumvent the issue. Nanotube dimensions were verified using microscopy and the average observed diameter was 155 nm. The PEG-based structures showed remarkable stability in water, salt water, and sodium hydroxide solution.

Lean construction theory is universally being applied in many actual projects for productivity improvement and process innovation. Most of proposed lean approaches, however, could not guide an actual implementation to the level of expected improvement, largely due to their inapplicability under in-situ circumstances. To reduce the gap between the theoretical approach and practical application, this paper suggests an action research approach integrated with lean construction theory to provide more practical solutions in a real setting. The results of a pilot case study showed that productivity was almost doubled than before applying proposed approach. Effectiveness of this framework will be further validated through applying to more broad case applications.

The static structure and dynamic behavior of cadmium sulfi de nanoparticles suspended in block copolymer matrix are investigated using transmission electron microscopy, small-angle X-ray scattering, and X-ray photon correlation spectroscopy. The transmission electron microscopy study shows that cadmium sulfi de nanoparticles are preferentially segregated within the polyisoprene domain of a poly(styrene-block -isoprene) diblock copolymer. For the dynamics study, X-ray photon correlation spectroscopy captures the relaxation process of cadmium sulfi de nanoparticles. The measured characteristic relaxation time reveals that the observed dynamics are hyperdiffusive. The characteristic velocity and corresponding activation energy, which are hallmarks of a hyperdiffusive system, are determined from the relationship between the characteristic relaxation time and the wavevector.the BCP provide a means to precisely control the spatial organization of the NPs. Theoretical investigations have suggested that a synergetic interaction between NPs and a self-organizing BCP matrix could produce hierarchically structured functional hybrid materials. [1][2][3] We refer to these nanocomposites as NP-BCPs. Such material design fl exibility is utilized to tune the electrical, [ 4 ] magnetic, [ 5 ] or biomedical [ 6 ] properties of targeted NP-BCPs. Despite recent progress on the fabrication techniques and contemporary applications of NP-BCPs, the equilibrium state and structural dynamics of these materials still remains poorly understood. This is in part because NP-BCPs compound the diffi culties caused by the entropic and enthalpic interactions between NPs and the BCP domain. In addition, many of the key methods for structural elucidation are less useful for characterizing dynamic behavior.The unique self-assembling features of the BCP can be used to synthesize NPs. Specifi cally, poly(styrene-block -2 vinylpyridine) (S2VP) or poly(styrene-block -4 vinylpyridine) (S4VP), which are solvent-selective diblock copolymers, provide a micellar structure for metal/semiconductor

α-Ga2O3 has the largest bandgap (~5.3 eV) among the five polymorphs of Ga2O3 and is a promising candidate for high power electronic and optoelectronic devices. To fabricate various device structures, it is important to establish an effective dry etch process which can provide practical etch rate, smooth surface morphology and low ion-induced damage. Here, the etch characteristics of α-Ga2O3 epitaxy film were examined in two fluorine-based (CF4/Ar and SF6/Ar) inductively coupled plasmas. Under the same source power, rf chuck power and process pressure, an Ar-rich composition of CF4/Ar and an SF6-rich composition of SF6/Ar produced the highest etch rates. Monotonic increase in the etch rate was observed as the source power and rf chuck power increased in the 2CF4/13Ar discharges, and a maximum etch rate of ~855 Å/min was obtained at a 500 W source power, 250 W rf chuck power, and 2 mTorr pressure. A smooth surface morphology with normalized roughness of less than ~1.38 was achieved in the 2CF4/13Ar and 13SF6/2Ar discharges under most of the conditions examined. The features etched into the α-Ga2O3 layer using a 2CF4/13Ar discharge with 2 mTorr pressure showed good anisotropy with a vertical sidewall profile.

ABSTRACT:The demand of Liquefied Natural Gas (LNG) is on a steady increase, and the estimation of world LNG consumption will be doubled by 2030 compared with 2005. In the wake of increasing demand, numerous LNG plant projects are under construction and many new projects are in the planning stage. However, since there are limited numbers of companies that have a full capability of core technologies and licenses related with LNG plant construction, companies that are less experienced in LNG plant projects suffer from a lack of project management ability, such as process planning, schedule management, and risk management particularly for early stage of project initiation. A number of researches have highlighted the importance of the early design phase in EPC-type plant projects and its consequential impact on project performance. Therefore, this study aims to develop a risk management system to support an efficient decision-making process during the design phase. The research procedure consists of three parts. First, we identified a total of 82 design risk factors composed of typical risk items related to any plant projects and LNG-specified design risks. Second, we developed a risk management framework based on the stage-gate process, composed of three sub-stages: Pre-stage, On-stage and Poststage of each sub-design phase. Finally, we applied this procedure to plant layout stage. This study is expected to support better decision-making in the design phase of overseas LNG plant projects by integrating the stage-gate process and risk management cycles for making prompt "go/no-go decisions" on the key decision checkpoints.