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This paper describes an experimental study on the structural behavior of the joint plane between a RC (reinforced concrete) wall and a SC (steel plate concrete) wall under out-of-plane flexural loads and in-plane shear loads. L- and I-shaped test specimens were produced to efficiently assess the flexural and shear behavior of the structures. In order to consider dynamic loads such as earthquakes, cyclic loading tests were carried out. The out-of-plane flexural test conducted on the short development length L-shaped specimen with a non-contact splice length exhibited a ductile failure mode that surpassed the nominal strength, verifying the validity of the splice length used in its design. The in-plane shear test was conducted on two I-shaped specimens varying the compositional presence of horizontal bars in the SC member. The test results showed that the capacity of the specimens was more than their nominal strength regardless of the compositional presence of horizontal bars. The shear friction tests of the RC–SC member connection conducted on the other L-shaped specimen caused the failure of the SC member and verified a shear resistance of at least 85.5% compared to the theoretical value.

A polymer waveguide was fabricated to amplify the evanescent optical field for biosensing. The structure of waveguide was designed to propagate a normal single mode at the input and output regions for low loss beam coupling and propagation. A sensing region was formed in the middle of the waveguide to activate the evanescent mode and to induce high birefringence by depositing a thin dielectric film with a high refractive index on a single mode waveguide. A polymer waveguide with the dimensions of 7 μm-width and 2.5 μm-thickness was fabricated by photolithography and dry-etching. The active region of the TiO 2 thin film was fabricated with the dimensions of 20 mm-length, 20 nm-thickness and 2 mm-tapered tail. A polarimetric interference technique was used to evaluate the evanescent waveguide biosensor, and biomaterial such as glycerol was tested. The sensitivity of the sensor increased with increasing TiO 2 film thickness. For the fabricated waveguide with a 20 nm-thick TiO 2 film, the measured index change to the lead phase variation of 2 π was 1.8 × 10 −4 .

Periodically poled LiNbO3 (PPLN) was fabricated with a 7.3 μm domain-inverted period, a 1.5 μm thick photoresist grating and a 3 μm pattern open width through the electric field poling process using the liquid electrode technique. After slicing the wafers to a final dimension of 30 × 10 mm2, the specimen was poled and then annealed. Second harmonic generation (SHG) was investigated to evaluate the domain reversal properties of the PPLN. The fundamental and second harmonic waves of a 7.3 μm PPLN waveguide were 1087 ± 1 nm and 544 ± 0.5 nm, respectively. The average duty cycle of the etched PPLN was estimated to be 50.6 ± 3.3%. For PPLN in Ti:LN waveguide with a 6.8 μm domain-inverted period, the fundamental guided-mode wave and the radiated SHG wavelength were 1068 nm and 534 nm. The SHG power increased proportionally to the square of the input pumping power. 330 μW of SHG power was observed for a coupled power of 29 mW with a conversion efficiency of 1.138%. The average duty cycle of the etched PPLN was determined to be 50.2%.

Ridge waveguides were fabricated using an external field, a precision lapping machine and neutron loop discharge (NLD) in magnesium-oxide-doped lithium niobate. The measured quasi-phase-matching (QPM) wavelength of the second-harmonic generation (SHG) in a 30 mm long periodically poled magnesium-doped lithium niobate (PPMgLN) ridge waveguide which has a domain period of 6.8 μm is about 532 nm. A fabricated periodically poled magnesium-doped lithium niobate ridge waveguide was duty cycle of 51.9 ± 2.83% and demonstrated second-harmonic generation. By using this periodically poled magnesium-doped lithium niobate ridge waveguide, highly effective, low-cost optical devices with high power or short wavelength can be achieved.

In this study, we have developed a novel micro wire straightener using the direct wire heating and pulling (DWHP) method. The straightener can remove the bend of the micro wire (

The 0.5 mm thick bulk periodically poled LiNbO 3 (PPLN) crystals have been fabricated by an electric field poling process using a liquid electrode technique to investigate the effect of photoresist grating (PR) thickness and pattern open width on the periodicity and the duty cycles of PPLNs. No periodic deterioration of + Z , − Z surfaces and cross section (+ Y ) of PPLN with a domain-inverted period of 16.6 μm and a 3.0 μm thick PR is found. The average duty cycle of the PPLN is determined to be 49.9 ± 3.3%. It suggests that a 3.0 μm thick and a 16.6 μm period PR with a pattern open width of 3.3 μm are advantageous to the fabricated PPLN performance.

Periodically poled LiNbO3 (PPLN) has been fabricated with a 16.6 μm domain-inverted period, a 3.0 μm thick photoresist grating, and a 3.3 μm pattern open width through the electric field poling process using the liquid electrode technique. The average duty cycle for the fabricated PPLN was measured to be 49.9 ± 3.3%. The effect of annealing temperatures on the domain shape of PPLN was investigated in the range of 300 to 800 °C. At 300 °C, residual stress was not relieved completely. As the annealing temperature increases above 800 °C, the domain shape changes. However, no domain damage was observed for annealing temperatures from 400 to 700 °C. The best annealing temperature for the suppression of domain damage and the improvement in the crystalline quality was found to be 400 °C.

The DC-drift of Ti: LiNbO 3 electro-optic device was experimentally shown to be related to the unstable dielectric properties of the oxide buffer layer between waveguide and signal electrodes. A chemical-cleaning process removing alkali contaminants from the SiO 2 buffer layer was used to minimize the DC-drift. The lowering of the contamination level of the buffer layer was confirmed by X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS). The DC-drift was also found to occur due to the irregular effective electric field across the waveguides, which originates from the unstable resistivity of the buffer layer by high content of OH groups. These OH groups were shown to be effectively removed through the optimized annealing process after the deposition of SiO 2 buffer layer.

A plasma dry etching technique has been applied to the fabrication of LiNbO3 optical waveguide with a ridge structure for broadband operation. The etching characteristics of a LiNbO3 single crystal have been investigated according to various ratios of Ar/C3F8 gas mixture. A Ni metal was used as a dry etching mask. The effects of a gas mixture ratio on etching profile angle, sidewall roughness and etching rate were also studied. The etching surface roughness was evaluated by atomic force microscopy (AFM). The etch rate and profile was observed by scanning electron microscopy (SEM). The optimum etching conditions, considering etch rate, profile and surface roughness, were obtained at the 20 sccm C3F8 gas flow. � 2005 Elsevier B.V. All rights reserved.

Ti-indiffused LiNbO3 waveguides have been used for various high speed optical devices, such as modulators, switches and sensors, because of their electro-optic effect. In order to broaden the modulation bandwidth of an optical modulator above 10 GHz, both impedance matching and optical and RF phase velocity matching should be obtained at the high frequency range. This can be obtained by increasing the effective contact area of the CPW (co-planar waveguide) electrodes with air by means of LiNbO3 substrate etching. We studied the properties of LiNbO3 dry etching, in terms of the etching rate, etching angle and surface roughness, using a neutral loop discharge (NLD) plasma.

In shell-and-tube heat exchangers, the shell-side fluid flow enters and leaves through nozzles which are mounted on the shell wall. The cross-flow in the nozzle region has an impact on the shell-side pressure drop and heat transfer. The influence on the heat transfer is investigated by means of experiments with four double-pipe heat exchangers. The results show that the influence is greater, the shorter the heat exchangers are, and the smaller the ratio of the free cross sectional areas of the nozzle to that of the shell-side. A correlation suitable for predicting the heat transfer coefficient is presented in this paper. The correlation consists of the Nusselt number for the flow in the nozzle region and that for the flow in the annulus.

Pressure drop and heat transfer characteristics, in the form of fRe and Nu respectively, of hydrodynamically developed laminar flow through a cylindrical shell containing a bundle of seven tubes with a uniform tube-wall temperature are determined by solving the momentum and energy balance equations in finite difference forms, using a forward-marching, implicit method. Correlations suitable for predicting fRe are derived as functions of the tube-to-shell radius ratio (rt/rs) and the non-dimensional pitch radius (rp/rs). Local Nusselt numbers and logarithmic-mean Nusselt numbers are presented graphically for Graetz numbers up to 105. Nusselt numbers in the thermally developing range are also obtained from the mean velocity gradients at the tube walls applying the asymptotic solution due to Levěque.

Summary Chlamydomonas seynis zoospores adapted to air levels of CO 2 rather than to 5% CO 2 in air were capable of active photosynthesis at alkaline p H in the presence of a low (0.38 µM) concrntration of CO 2 . The patterns of detergent-soluble polypeptides, analyzed by two-dimensional isoelectric focusing-polyacrylamide gel electrophoresis, were compared in air- and 5% CO 2 -adapted zoospores. Both types of zoospores had at least 163 polypeptides in common, but diffrred with respect to an additional fifteen polypeptides. Of the latter, three polypeptides were specific to air-adapted zoospores. One of these was a diffuse spot (M r = 42,000) whose p I value ranged from 5.2 to 5.4. The other two polypeptides had the same p I value of approximately 7.7 and slightly different M r -values (20,000 and 22,000). In 5% CO 2 -adapted zoospores, six polypeptides varied from the aforementioned three polypeptides in either the M r -value or p I . The differences could be explained in terms of protein modification. The results suggest that the polypeptides specific to air-adapted zoospores could be linked to their photosynthetic capability at subsaturating concentrations of CO 2 .