Millimeter Wave Imaging System Using Monopole Antenna with Cylindrical Reflector and Silicon Lens

We built a reflection imaging system that uses a monopole antenna with a cylindrical reflector and silicon semi-spherical lens for millimeter waves to identify detachments of alabaster from support material such as wood and stone, which can be subject to painting deterioration. Based on the electric field property near the monopole antenna in the system and the lens effect, the system was able to clearly image a test sample made of 2-mm width aluminium tape, which was placed within a range of approximately 10 mm from the lens. In practical imaging testing using a detachment model, which consists of alabaster and wood plating, the result also showed the possibility of observing slight detachment of the alabaster from the wood more easily than an imaging with large numerical aperture.     

Transient Crack Growth Behavior Under Cycle/Time-Dependent Step Loading for Pb-Containing and Pb-Free Solders

In the present study, fatigue crack growth tests of Pb-containing [Sn-37Pb (wt.%)] and Pb-free [Sn-3.0Ag-0.5Cu (wt.%)] solders were performed under cycle/time-dependent step loading at a constant J-integral range (ΔJ). The C ^* parameter was also estimated for discussing time-dependent crack growth behavior. The experimental results indicated that acceleration of the crack growth rate at the beginning of the second loading step was induced when the C ^* value for the first loading step was high, regardless of time- or cycle-dependent crack growth and for both Sn-37Pb and Sn-3.0Ag-0.5Cu solders. The length of the acceleration region of the crack growth rate for both solders was in good agreement with the creep damage zone size estimated by the creep zone model proposed by Riedel and Rice.     

Lipid Bilayers on a Picoliter Microdroplet Array for Rapid Fluorescence Detection of Membrane Transport

This paper describes picoliter‐sized lipid bilayer chambers and their theoretical model for the rapid detection of membrane transport. To prepare the chambers, semispherical aqueous droplets are patterned on a hydrophilic/hydrophobic substrate and then brought into contact with another aqueous droplet in lipid‐dispersed organic solvent, resulting in the formation of the lipid bilayers on the semispherical droplets. The proposed method implements the lipid bilayer chambers with 25‐fold higher ratio of lipid membrane area (S) to chamber volume (V) compared to the previous spherical droplet chambers. Using these chambers, we are able to trace the time‐course of Ca²⁺ influx through α‐hemolysin pores by a fluorescent indicator. Moreover, we confirm that the detection time of the substrate transport is inversely proportional to the S/V ratio of the developed chambers, which is consistent with the simulation results based on the developed model. Our chambers and model might be useful for rapid functional analyses of membrane transport phenomena.     

Effect of compression overload on fatigue strength improved by ICR treatment

ICR (Impact Crack-closure Retrofit) treatment was developed for extending fatigue life of cracked steel structures by closing the fatigue crack opening. By applying the ICR treatment to as-welded condition, compressive stress remains at weld toe. Therefore, ICR treatment can be used for the improvement of fatigue strength of welded joint at the same level of the other fatigue strength improved techniques. If a compression overload is subjected after ICR treatment, however, the residual compressive stress at weld toe will shift the tensile stress region. Accordingly, improved fatigue strength of welded joints by ICR treatment will be reduced after the compression overloaded. In order to investigate the effect of the compression overload on fatigue strength improved by ICR treatment, fatigue tests of out-of-plane gusset specimens were carried out. As the results, fatigue strength improved by ICR treatment was hardly reduced under the compression overload condition of nominal stress of ?190 MPa.     

Evaluation of the plug‐in hybrid electric vehicle considering learning curve on battery and power generation best mix

The plug‐in hybrid electric vehicle (PHEV) is a technology intended to reduce CO₂ emissions in the transport sector. This paper presents scenarios that show how widely used PHEVs will be in the future, how much CO₂ emissions will be reduced by the introduction of PHEVs, and whether there will be serious effects on the power supply system. PHEVs can run on both gasoline and electricity, and therefore we evaluate CO₂ emissions not only from gasoline consumption but also from electricity consumption. Consideration of the distribution of daily trip distances is important for evaluating the economical benefits and CO₂ emissions resulting from the introduction of PHEVs. Also, future battery costs are very important in constructing PHEV growth scenarios. The growth of the number of PHEVs will make battery costs lower. Thus, we formulate an overall model that combines the passenger car sector and power supply sector, taking account of the distribution of daily trip distances and incorporating a learning curve for battery costs. We use the iteration method to provide a learning curve that is nonlinear. Therefore, we set the battery cost only in the first year of the simulation: battery costs in the later years are calculated in the model. We focus on a 25‐year time period in Japan, starting from 2010, and divided into 5 parts (1st to 5th). The model selects the most economical combinations of car types and power sources. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 176(2): 31–40, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21098     

Synergistic or antagonistic modulation of oviposition response of two swallowtail butterflies, Papilio maackii and P. protenor, to Phellodendron amurense by its constitutive prenylated flavonoid, phellamurin

Papilio maackii females prefer a rutaceous plant, Phellodendron amurense, for oviposition, whereas another semi-sympatric Rutaceae feeder, Papilio protenor, never exploits this plant as a host in nature. However, the larvae of both species perform well on this plant in the laboratory. Phellamurin, a flavonoid present in the organic fraction from P. amurense inhibits egg laying by P. protenor. We examined whether phellamurin is involved in the differential acceptance of P. amurense by the two butterflies. The ovipositing females of P. maackii readily accepted P. amurense and a methanolic extract of the foliage, while P. protenor rejected them entirely. However, the aqueous fraction derived from the extract elicited significant oviposition responses of similar levels from the two species. Phellamurin did not induce oviposition behavior in P. protenor females. In contrast, P. maackii was stimulated to oviposit by phellamurin at concentrations exceeding 0.2%. The response was dose-dependent and reached ca. 70% at 2% phellamurin, which is approximately equivalent to its natural abundance in young leaves of P. amurense. Since the aqueous fraction was very stimulatory to both species, the combined effect of phellamurin and the aqueous fraction on oviposition was tested. The addition of phellamurin to the aqueous fraction enhanced the ovipositional activity of P. maackii, but dramatically suppressed the oviposition response of P. protenor even at 0.1% concentration. These results, taken together with those obtained from electrophysiological recordings with foretarsal chemosensilla, indicate that phellamurin acts as an oviposition stimulant for P. maackii, and as a potent deterrent for P. protenor. The results suggest that host range expansion or host shifts may be made by ovipositing females that overcome phytochemical barriers.     

Integrated sorption and diffusion model for bentonite. Part 2: porewater chemistry,sorption and diffusion modeling in compacted systems

It is important to understand the coupled processes of sorption and diffusion of radionuclides (RNs) in compacted bentonite, and to develop mechanistic models that can aid in the prediction of the long-term performance of geological disposal systems of radioactive waste. The integrated sorption and diffusion (ISD) model was developed based on the consistent combination of clay–water interaction, sorption and diffusion models. The diffusion model based on the electrical double layer theory describing relative ionic concentrations and viscoelectric effects at the negatively charged clay surface was coupled with porewater chemistry and sorption models. This ISD model was successfully tested for various actinides with a complex chemistry (Np(V), Am(III), U(VI) under conditions where variably charged carbonate complexes are formed) considered in Part 1, by using published diffusion and sorption data (D_a, D_e, K_d) as a function of partial montmorillonite density. Quantitative agreements were observed by considering uncertainty in porewater chemistry and dominant aqueous species. It can therefore be concluded that the ISD model developed here is able to adequately explain the sorption and diffusion behavior of various RNs with a complex chemistry in compacted bentonites. The performed modeling indicates that uncertainties are mainly related to porewater chemistry and RN speciation and that these parameters need to be carefully evaluated.