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The transition to 450 mm wafer manufacturing has already become a development trend for the semiconductor industry. To handle the larger wafer size, the conveyor-based automated material handling system (AMHS) is considered as the next-generation transportation. However, there is not any effective method for handling prioritized lots for 450 mm conveyor-based AMHS. This study developed an effective dispatching method named the "conveyor preemptive dispatching" (CPD) method for conveyor-based AMHS to minimize the average variable time of hot lots with the minimum impact to the transport of normal lots. Experiment results revealed that the CPD demonstrates better performance than the existing method. The CPD method reduced the average variable time by 59 % (from 14.572 to 5.904 s) for hot lots and 31 % (from 3962.394 to 2741.889 s) for normal lots. It expedites the movement of lots and significantly reduces lot average variable time and will effectively enhance the throughput of lots transportation. [ABSTRACT FROM AUTHOR]

In order to analyze the influence of the lateral size of graphene oxide (GO) on the properties of natural rubber/ graphene oxide (NR/GO) nanocomposites, three different sized graphene oxide sheets, namely G1, G2 and G3 were used to fabricate a series of NR/GO nanocomposites by latex mixing. The results indicate that adding GO can remarkably increase the modulus of NR. The enhancement of modulus is strongly dependent on the size of GO sheets incorporated. G1 with smallest sheet size gives the maximum reinforcement effect compared with G2 and G3. Dynamic mechanical measurement and swelling ratios (Qf/Qg) indicate that G1 has stronger interfacial interaction with NR. XRD shows G1 is more effective in accelerating the strain-induced crystallization (SIC) of NR. The strong interfacial interaction facilitates the stress transfer and strain-induced crystallization, both of which lead to the improved modulus. [ABSTRACT FROM AUTHOR]

The properties of the evaporation heat transfer and pressure drop for refrigerant R-134a flowing in a plate heat exchanger are examined experimentally. Three plates of commercial geometry with a corrugated sine shape of a chevron angle form the two vertical counterflow channels in the exchanger. Results demonstrate that the evaporation heat transfer coefficient of R-134a in the plates is much larger than that in circular pipes.

A quantitative real-time polymerase chain reaction (qPCR) is a robust means by which to monitor toxin-producing cyanobacteria. However, qPCR usually requires DNA extraction, which is a timeconsuming, labor-intensive pretreatment. To be able to quickly determine the potential of cyanotoxin contamination in the field, a rapid pretreatment method for DNA extraction and a portable qPCR device are needed. In this study, we applied a microwave-based method for the qPCR pretreatment and a multicolor portable qPCR with UPL and TaqMan probes to quantify toxigenic and total Microcystis. The method was tested using laboratory cultures of toxigenic Microcystis aeruginosa PCC7820. The qPCR results showed the cycle thresholds value (Ct value) correlated well with cell numbers, with detection limit at about 1,000 cells/ml. This scheme was applied in 22 environmental samples from six drinking water reservoirs (DWRs) in Taiwan. Although the results for qPCR were about four times higher than those of microscopic observation, good correlation between qPCR and microscope methods were obtained (r-square: 0.79, P<0.01). The ratios of toxigenic Microcystis to total Microcystis in two reservoirs, Sin-Shan Reservoir and Shih-men Reservoir, were less than 10%. In three other reservoirs, Ren-Yi-Tan Reservoir, Nan-Hua Reservoir and Bao-Shan Reservoir, much higher (>46.1%) ratios were obtained. The scheme may assist quick assessment of the risk associated with toxic cyanobacteria in DWRs. [ABSTRACT FROM AUTHOR]

An ultrahigh resolution and high-flux undulator beamline U9-CGM, with a cylindrical grating monochromator and covering an energy range from 5 to 100 eV, has been constructed. Two separate entrance slits are included to provide different incident angles, hence to optimize the overall performance. This beamline delivers an average photon flux of 6×1010 photons/s with the entrance and exit slit openings at 10 μm. An energy resolving power of 110 000 with a photon flux of 1×1010 photons/s was obtained at 16 eV with the 1800 line/mm grating and at 64 eV with the 1600 line/mm grating, with the entrance and exit slit openings at 3 and 5 μm, respectively. A differentially pumped gas cell is used to attenuate high-order light by up to four orders of magnitude. This beamline will be a powerful tool for research in ultrahigh resolution spectroscopy of atoms, molecules, and condensed matter. [ABSTRACT FROM AUTHOR]

A simple approach to predict the adsorption capacity and isotherm curvature of organic compounds onto activated carbon in natural water was investigated. A combination of the well-known equivalent background compound (EBC), and the simplified competitive adsorption model (SCAM) was employed to delineate the equilibrium capacity. This SCAM-EBC approach may reduce the numerical and experimental effort to obtain the parameters required to predict the adsorption capacity for a specific adsorption system. Several sets of experimental data, including weakly adsorbing (MTBE), strongly adsorbing compounds (TCP, atrazine, and chloroform), and two taste and odor causing compounds (MIB and geosmin) onto different activated carbons in three natural waters and a synthetic groundwater, were tested to verify the SCAM-EBC approach. Based on the approach, a parameter, called relative adsorptivity, describing the adsorption preference of the adsorbent between EBC and the target compound was employed to simulate the isotherm curvature in natural water. The relative adsorptivity of the SCAM-EBC approach is constant and can be directly obtained from the SCAM-EBC parameters in a specific adsorption system. The potential and extent of isotherm curvature can be simulated by only changing the parameter of relative adsorptivity. The marked isotherm curvature was found while the relative adsorptivity is larger than 2.0 to 4.0 for all the systems tested. [ABSTRACT FROM AUTHOR]

Equilibrium and kinetic adsorption of methyl tert-butyl ether (MTBE) onto three coal-based activated carbons, one coconut-based activated carbon, and two zeolites are elucidated in this study. Natural organic matter (NOM) and MTBE competed for the adsorption of activated carbons to different extents. The ideal adsorbed solution theory (IAST) combined with the equivalent background compound (EBC) model can adequately describe the NOM competition and predict the isotherms of MTBE onto the activated carbons. No competitive adsorption was observed for one of the zeolites, mordenite, due to the molecular effect. Besides, the aperture size, and the SiO2/Al2O3 ratio of the zeolite may also play an important role in the adsorption of MTBE from the aqueous phase. The surface diffusion model accurately simulated the transport of MTBE within the adsorbents employed in different water matrices. For all the activated carbons tested, the surface diffusivity of MTBE in natural water was nearly equal to that in deionized water, indicating that no apparently hindering effect occurs. A much slower adsorption kinetic of mordenite in natural water was observed since the opening apertures on mordenite may be appreciably hindered and blocked by NOM. [ABSTRACT FROM AUTHOR]

In this study, the effect of three oxidants, sodium hypochlorite, potassium permanganate, and ozone, were tested for the removal of 2-MIB with presence of cyanobacteria. Algae in water samples from the source water of Feng-Shen waterworks (FSW), Taiwan were cultivated at 30°C with continuous light at an intensity between 2,500 and 3,400 lux. During the cultivating process, water samples were analyzed for nutrients, light absorbance at 665nm (A665), and 2-MIB concentration. The 2-MIB concentrations within the incubated samples increased to as high as 1,000 ng/L to 2,000 ng/L, although no extra nutrients were added to the raw water. After 2 to 3 days incubation, the intracellular 2-MIB concentration was as high as 70% of the total 2-MIB in the samples. The algae that developed were mainly cyanobateria, and more than 90% belonged to the Genus Oscillatorias. An almost 100% removal of both 2-MIB and geosmin in the raw water was observed after ozonation for 10 minutes at a dosing rate of 0.91 mg/l-min. Chlorine and permanganate were much less effective, both removing only about 11% of the 2-MIB within 60 minutes at oxidant concentration of 10 mg/l. Oxidation of the cultivated samples showed that chlorine and permanganate may damage algae cells causing them to release intracellular 2-MIB. During the 60 minutes of reaction time, the total 2-MIB concentrations (intracellular plus dissolved) varied by no more than 10%, however, the ratios between dissolved and total 2-MIB concentrations increased. Two effects of ozonation on the 2-MIB concentration in the cultivated samples were observed when the algae were young, namely 2-MIB release from damaged cells and 2-MIB oxidization. The rates of 2-MIB release and 2-MIB destruction were similar. However, old algae cells were more easily damaged. As a result, intracellular 2-MIB was released faster, and the soluble 2-MIB was destroyed more quickly by ozonation. [ABSTRACT FROM AUTHOR]

Experiments are carried out here to measure the evaporation heat transfer coefficient h[subr] and associated frictional pressure drop ΔP[subf] in a vertical plate heat exchanger for refrigerant R-410A. The heat exchanger consists of two vertical counterflow channels which are formed by three plates whose surface corrugations have a sine shape and a chevron angle of 60 deg. Upflow boiling of refrigerant R-410A receives heat from the hot downflow of water. In the experiments, the mean vapor quality in the refrigerant channel is varied from 0.10 to 0.80, the mass flux from 50 to 100 kg/m²s, and the imposed heat flux from 10 to 20 kW/m² for the system pressure fixed at 1.08 and 1.25 MPa. The measured data indicate that both h[subr] and ΔP[subr] increase with the refrigerant mass flux except at low vapor quality. In addition, raising the imposed heat flux is found to significantly improve h[subr] for the entire range of the mean vapor quality. However, the corresponding friction factor f[subtp] is insensitive to the imposed heat flux and refrigerant pressure. Based on the present data, empirical correlations are provided for h[subr] and f[subtp] for R-410A in the plate heat exchanger. [ABSTRACT FROM AUTHOR]

The Kaoping River Basin, located in southern Taiwan, flows through approximately 171 km and drains towards the South Taiwan Strait. It is the largest and the most intensively used river basin in Taiwan. Based on the results from the pollutant sources investigation and water quality analysis, the main water pollution sources of the Kaoping River were livestock wastewater from hog farms, municipal wastewater, industrial wastewater, leachate from riverbank landfills, and non-point source (NPS) pollutants from agricultural areas in the upper catchment. Concern about the deteriorating condition of the river led the Government of Taiwan to amend the relevant legislation and strengthen the enforcement of the discharge regulations to effectively manage the river and control the pollution. The following remedial strategies have been taken to improve the river water quality since 2001: (1) hog ban in the upper catchment of the Kaoping River Basin, thus, 510 thousand hogs have been removed/relocated; (2) removal of riverbank landfills; (3) enforcement of the industrial wastewater discharge standards; (4) sewer system construction in five cities along the river corridor; (5) application of best management practices for NPS pollutant control; (6) application of natural wastewater treatment systems (e.g. land treatment, constructed wetland, overland flow, riverbank sedimentation/aeration pond) for domestic wastewater treatment in rural areas; and (7) construction of the watershed geographical information system (GIS) and real time water quality monitoring system to effectively monitor and manage the watershed. Recent water quality investigation results indicate that the biochemical oxygen demand (BOD) and nutrient loadings to the Kaoping River have been significantly reduced and the water quality has been improved after the implementation of the remedial strategies described above. Results and experience obtained from this study will be helpful in designing the watershed management strategies for other similar river basins. [ABSTRACT FROM AUTHOR]

Investigates the removal of arsenic from groundwater using point-of-use reverse osmosis and distilling devices. High concentrations of arsenic in the groundwater of the northeastern and southwestern coast areas of Taiwan; Selection of three commercially available reverse osmosis systems and two distillers to test their removal efficiency of arsenic from synthetic and real ground water; Percentage of arsenic removal for the distilled systems.

A three-dimensional unsteady numerical computation was carried out here to investigate the effects of the thermal boundary condition on the convection flow in a vertical, bottom heated cylinder containing air. The thermal condition at the sidewall of the cylinder is assumed to be thermally well insulated or perfectly conducting. Results were obtained for air in a cylinder of finite aspect ratio (Gamma = 2) for various thermal Rayleigh numbers. The predicted results indicate that the flow in the sidewall insulated cylinder is highly asymmetric even at steady state and contains multicellular vortices. The flow formation processes leading to the above structures are relatively complicated. In the early transient two axisymmetric circular vortex rolls, one on top of another, appear. Then the rolls merge asymmetrically. In the late stage the flow deflection by the cylinder top and bottom results in a very complex flow. In the cylinder with a perfectly conducting sidewall the transition from a steady to a time dependent flow is subcritical. However, in the cylinder with an insulated sidewall the flow transition is supercritical. [ABSTRACT FROM AUTHOR]