Corrosion rate of parent and weld materials of F82H and JPCA steels under LBE flow with active oxygen control at 450 and 500 °C

Corrosion behavior of parent and weld materials of F82H and JPCA was studied in the circulating LBE loop under impinging flow. These are candidate materials for Japanese Accelerator Driven System (ADS) beam windows. Maximum temperatures were kept to 450 and 500 °C with 100 °C constant temperature difference. Main flow velocity was 0.4-0.6 m/s in every case. Oxygen concentration was controlled to 2-4 × 10⁻⁵ mass% although there was one exception. Testing time durations were 500-3000 h. Round bar type specimens were put in the circular tube of the loop. An electron beam weld in the middle of specimens was also studied. Optical microscopy, electron microscopy, X-ray element analyses and X-ray diffraction were used to investigate corrosion in these materials. Consequently corrosion depth and stability of those oxide layers were characterized based on the analyses. For a long-term behavior a linear law is recommended to predict corrosion in the ADS target design.     

Hyperbranched-linear poly(ether sulfone) blend films for proton exchange membranes

Hyperbranched poly(ether sulfone) polymers having sulfonyl chloride end-groups is blended at up to 30 w% with linear poly(ether ether ether sulfone)s and a two-phase system is generated via spinodal decomposition upon drying from a DMAc solution. Conversion of the end-groups from sulfonyl chloride to sulfonic acid is accomplished using 16 M H₂SO₄ that is also believed to introduce additional sulfonic acid groups at the interface of the linear polymer. The blend films before and after conversion to sulfonic acid have similar tensile strengths as films composed of solely linear polymer (yield stress >40 MPa and Young's modulus >3 GPa m). These films are designed to test the viability of hyperbranched polymers as fuel cell membranes. Proton conductivities of up to 0.03 S cm⁻¹ are observed at 80 °C and 90% R.H indicating a good potential for use of hyperbranched polymers as a proton conduction material.     

Double liquid crystalline side-chain type block copolymers for hierarchically ordered nanostructures: Synthesis and morphologies in the bulk and thin film

Well-defined double liquid crystalline side-chain type block copolymers (DLC-BCPs) were synthesized by nitroxide-mediated living free radical polymerization (NMP) of two different types of styrene monomers containing liquid crystalline moieties. The molecular weights and compositions were controlled by changing the polymerization time and/or the feed amount of the monomers. The bulk morphologies were studied using wide-angle X-ray scattering (WAXS), small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). DLC-BCPs were favored to form microphase-separated lamellar structures over a wide range of volume fractions. By controlling the annealing conditions, further higher-ordered hierarchical nanostructures were obtained with a long-range alignment, in which the semi-crystalline side-chains were oriented parallel to the interface of microphase-separated lamellar structure. Thin film morphology was investigated using atomic force micrography (AFM). The formation of lamellar nanostructure with a long-range alignment vertically oriented to the silicon wafer substrate was achieved by simple thermal annealing.     

Integrated biosensor employing a surface photovoltage technique

A monolithically integrated biosensor is constructed using a surface photovoltage (SPV) technique combined with a new patterning method for multiple enzyme integration. The SPV method provides a contactless sensing system leading to patterning flexibility. Photolithographical patterning methods using a water-soluble photocrosslinkable polymer (copolymer of dimethylacrylamide and cinnamoyloxyethylmethacrylate) are applied to immobilize the enzyme on a semiconductor surface. For bonding the enzyme membrane to the semiconductor surface, photoreactive poly-(meta azide styrene) is used, which bonds covalently with both the enzyme membrane and substrate. A pen-printing method has also been proposed for the patterning of enzyme films, which provides a simple method suitable for mass production.     

An approach to data fusion using uncertain knowledge in geographical information systems

Digital terrain maps have become widespread, and Geographical Information Systems (GIS) have moved into the limelight. One of the key technologies needed in GIS is data fusion reasoning. The function of data fusion is to consider various geographical data, such as “roads” and “slope,” and make a complete evaluation. In this paper, we propose a data fusion reasoning technology using uncertain knowledge. Data fusion knowledge contains some uncertainty. For example, our knowledge for evaluating mobility costs is uncertain because it is qualitative, such as “we want to refuse steep places.” We introduced two uncertainty reasoning mechanisms to represent such data fusion process. One is fuzzy reasoning, and the other is Dempster–Shafer theory. We also offer knowledge‐editing facilities for describing data fusion knowledge, such as a data flow diagram editor for designing data fusion process and a membership function editor for describing data abstraction methods. These knowledge editors facilitate the development and modification of data fusion knowledge base for GIS. © 1999 Scripta Technica, Electr Eng Jpn, 128(4): 65–76, 1999     

Spin‐Coated Highly Efficient Phosphorescent Organic Light‐Emitting Diodes Based on Bipolar Triphenylamine‐Benzimidazole Derivatives

A new series of star‐shaped bipolar host molecules, tris(4′‐(1‐phenyl‐1H‐benzimidazol‐2‐yl)biphen‐yl‐4‐yl) amine (TIBN), tris(2′‐methyl‐4′‐(1‐phenyl‐1H‐benzimida zol‐2‐yl)biphenyl‐4‐yl)amine (Me‐TIBN), and tris(2,2′‐dimethyl‐4′‐(1‐phenyl‐1H‐benzimidazol‐2‐yl)biphenyl‐4‐yl)amine (DM‐TIBN), that contain hole‐transporting triphenylamine and electron‐transporting benzimidazole moieties are designed based on calculations using density functional theory and successfully prepared. The theoretical calculation of energy levels of TIBN derivatives affords helpful ideas to design molecules with a favorable localization of highest occupied/lowest unoccupied molecular orbital (HOMO/LUMO) levels and a predefined enhancement of the triplet energy gap. The TIBN derivatives are employed as hosts to fabricate phosphorescent organic light‐emitting diodes (OLEDs) by the two methods of spin‐coating and vacuum deposition. Notably, the spin‐coated Me‐TIBN and DM‐TIBN devices exhibit a much better performance than the vacuum‐deposited ones, in which the spin‐coated DM‐TIBN device (47 500 cd m^?2, 27.3 cd A^?1, 7.3 lm W^?1) is outstanding with respect to other seminal work for solution‐processed OLEDs. More importantly, the new concept of localizing HOMO and LUMO levels for bipolar molecules is illustrated, and a facile strategy to tailor the energy levels by breaking the conjugation of hole‐ and electron‐transporting moieties is demonstrated.     

Performance of solar-desiccant cooling system with Silica-Gel (SiO2) and Titanium Dioxide (TiO2) desiccant wheel applied in East Asian climates

This paper shows the numerical investigation of the developed solar-desiccant cooling system applied in the East Asian climatic conditions with two different desiccant wheel coating materials – the Silica-Gel (SiO₂) and the Titanium Dioxide (TiO₂). The developed and validated numerical model of the system is currently used in the present study incorporating the two new materials in the desiccant wheel. The system was applied in temperate climate (Beijing and Tokyo), subtropical climate (Taipei and Hong Kong) and tropical climate (Manila and Singapore). The study showed that the specification of the solar-desiccant cooling system varies depending on the climatic conditions. It showed that the required flat plate collector area was getting larger from the temperate climate to the tropical climate. The storage tank requirement was getting bigger in the tropical climate compared to the subtropical and temperate climate. The volumetric flow rate of air was getting higher from temperate climate to tropical climate. In the comparison of the two materials, it was found that the Titanium Dioxide (TiO₂) can support lower indoor temperature and humidity ratio than the Silica-Gel (SiO₂) with the same specification of the solar thermal system and desiccant cooling system. In general, the solar-desiccant cooling system can provide the required indoor temperature and humidity ratio. However, for the hot and humid climate such as in tropical, large size of the solar thermal system is needed. In addition, higher volumetric flow of air to support the high cooling load is required. With regard to the new material, Titanium Dioxide, it is proven to be a good alternative material since it can provide lower indoor temperature and humidity ratio with higher cooling performance than the Silica-Gel.     

Benzothiazolamines as tire-derived molecular markers: sorptive behavior in street runoff and application to source apportioning

Wash-off and sorptive behaviors of two benzothiazolamines (BTs) [i.e., 2-(4-morpholinyl)benzothiazole (24MoBT) and N-cyclohexyl-2-benzothiazolamine (NCBA)] have been investigated as possible molecular markersfortire debris and/or road dust transported in highway runoff water. Sum of dissolved and particulate 24MoBT and NCBA concentrations in runoff water ranged from 15 to 417ng/L and from 22to 508ng/L, respectively. Proportions of NCBA in particulate (>0.7microm) phase (<9-79%) were larger than that of 24MoBT (<1-14%), which was consistent with their experimentally determined octanol/water partition coefficients (Kow; 10(4.23+/-0.14) for NCBA; 10(2.42+/-0.03) for 24MoBT). The organic carbon-normalized in-situ partition coefficient (Koc') observed in runoff events (10(4.69+/-0.28) for NCBA; 10(3.42+/-0.23) for 24MoBT) were 1 order of magnitude higher than those expected from their Kow, indicating strong affinity of BTs to suspended particulate matter (SPM) in runoff water. Furthermore, in desorption experiments lasting 24 h, we observed almost the same levels of Koc' as those in runoff events, implying that significant fractions of BTs are strongly associated with runoff particles and not easily available to equilibrium partitioning. NCBA was ubiquitous in sediments from the Nogawa River receiving runoff from the Chuo Highway, whereas many of those samples had undetectable levels of 24MoBT. All of above results indicate that NCBA would be more suitable than 24MoBT as a molecular marker for runoff particles loading the aquatic environment. By using SPM-weighted mean concentration of particulate NCBA, at least 3.3+/-1.6% of the mass in the Nogawa sediments is estimated to be from runoff SPM.