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Pesticidal activities of 4-[5-(2-cyclopropylaminopyrimidin-4-yl)-4-(4-chloro-2-fluoro-phenyl)thiazol-2-yl]-1-methylpiperidine, designated as Comp I, have been determined against a mosquito larva, Culex pipiens pallens, and a phytopathogenic fungus, Phytophthora capsici. Comp I was used as the leading compound in this study. The compounds were synthesized by reacting them with two functional groups, 3-thiophenyl and 2-thiophenyl groups, instead of 4-chloro-2-fluorophenyl group in Comp I. Other functional groups such as 2-aminothiazole, 2-(1-methylpiperazin-4-yl)thiazole, and 2-(piperazin-4-yl)thiazole were also introduced instead of 2-methylpiperidin-4-yl-thiazole of Comp I. Compounds designated as XIII-6~XV-7 were newly synthesized and their structures were confirmed by 1H- and 13C-NMR spectroscopy. Mosquito larvicidal activities of all the synthesized compounds against C. pipiens pallens were examined and Comp I among them showed the strongest larvicidal activity as 0.513 mM of LC50 value. The fungicidal activities of all the synthesized compounds against P. capsici were examined using the whole plant method. Among the XIII-6~XV-7 chemicals, 5-(2-cyclopropylaminopyrimidin-4-yl)-4-(thiophen-2-yl)thiazol-2-amine (VIII-6) showed the most potent antifungal activity in vivo. While the EC50 value of the commercial fungicide dimethomorph was 4.26 μM, EC50 of VIII-6 was 0.94 μM. Therefore, thiazole derivatives can be considered as viable candidates for the control of mosquito larvae and plant diseases.

The effect of interfacial reactions at the poly Si[sub 1-x]Ge[sub x]/HfO[sub 2] interface on the electrical properties of metal–oxide–semiconductor (MOS) capacitors with a poly Si[sub 1-x]Ge[sub x] (x=0,0.6)/HfO[sub 2] gate stack was investigated relative to the deposition conditions for the poly Si[sub 1-x]Ge[sub x] films, the Ge content of the poly Si[sub 1-x]Ge[sub x] films, and the annealing temperatures, by the electrical measurements and x-ray photoelectron spectroscopy. With an increase in hydrogen induced from doping or from deposition gas used during the deposition of poly Si[sub 1-x]Ge[sub x] (x=0,0.6) films, the accumulation capacitance of the MOS capacitors with a poly Si[sub 1-x]Ge[sub x]/HfO[sub 2] gate stack became anomalous and the leakage current increased significantly, due to the formation of hydroxyl(OH–) ions or the partial reduction of HfO[sub 2] at the grain boundary. With an increase in Ge content of the poly Si[sub 1-x]Ge[sub x] films, silicate formation became dominant at the poly Si[sub 1-x]Ge[sub x]/HfO[sub 2] interface, resulting in a significant decrease in leakage current. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The electrical measurements and x-ray photoelectron spectroscopy are used to investigate the effect of interfacial reactions at the poly Si(sub 1-x)Ge(sub x)/HfO2 interface on the electrical properties of metal-oxide-semiconductor (MOS) capacitors with a poly Si(sub 1-x)Ge(sub x) (x=0,0.6)/HfO2 gate stack. Silicate formation becomes dominant at the poly Si(sub 1-x)Ge(sub x)/HfO2 interface, resulting in a significant decrease in leakage current, in the poly Si(sub 1-x)Ge'(sub x)/HfO2 system.

As an emergency encountered in orthopedic practice requiring prompt diagnosis and aggressive treatment, necrotizing fasciitis around the hip must be discriminated from Fournier gangrene. The current case report describes a patient who suffered from bilateral type I necrotizing fasciitis around the hips, which was alleviated by prompt surgical debridement and intensive postoperative care. [ABSTRACT FROM AUTHOR]

The effect of interfacial reactions on the electrical properties of a polycrystalline (poly) Si[sub 1-x]Ge[sub x]/HfO[sub 2] gate stack were evaluated in terms of annealing conditions and the results were compared with those of a conventional poly-Si/HfO[sub 2] system. In the poly-Si[sub 0.4]Ge[sub 0.6]/HfO[sub 2] gate stack, silicate formation was the dominant reaction at the poly-Si[sub 0.4]Ge[sub 0.6]/HfO[sub 2] interface after annealing at 900 °C, resulting in the significant decrease in leakage current. From x-ray photoelectron spectroscopy analysis, the binding states of Hf silicates were clearly observed at a binding energy of about 16.1 eV in Hf 4f spectra and 102.7 eV in Si 2p spectra. However, in the poly-Si/HfO[sub 2] gate stack, the accumulation capacitance became undeterminable and the leakage current increased suddenly after annealing at 900 °C due to silicide formation at the poly-Si/HfO[sub 2] interface. The differences in reactions between a poly-Si/HfO[sub 2] interface and a poly-Si[sub 0.4]Ge[sub 0.6]/HfO[sub 2] interface are attributed to the accumulation of Ge. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The table of contents for the issue is presented.

The positive bias temperature instability (PBTI) characteristics of the n-channel metal-oxide-semiconductor field emission transistors which had different kinds of high-k dielectric gate oxides were studied with the different stress-relaxation times. The degradation in the threshold voltage followed a power-law on the stress times. In particular, we found that their PBTI behaviors were closely related to the structural phase of the high-k dielectric gate oxide. In an amorphous gate oxide, the negative charges were trapped into the stress-induced defects of which energy level was so deep that the trapped charges were de-trapped slowly. Meanwhile, in a crystalline gate oxide, the negative charges were trapped mostly in the pre-existing defects in the crystallized films during early stage of the stress time and de-trapped quickly due to the shallow energy level of the defects. [ABSTRACT FROM AUTHOR]

The oxidation characteristics of tungsten line pattern during the carbon-based mask-layer removal process using oxygen plasmas have been investigated for sub-50 nm patterning processes, in addition to the reduction characteristics of the WOx layer formed on the tungsten line surface using hydrogen plasmas. The surface oxidation of tungsten lines during the mask layer removal process could be minimized by using low-temperature (300 K) plasma processing for the removal of the carbon-based material. Using this technique, the thickness of WOx on the tungsten line could be decreased to 25% compared to results from high-temperature processing. The WOx layer could also be completely removed at a low temperature of 300 K using a hydrogen plasma by supplying bias power to the tungsten substrate to provide a activation energy for the reduction. When this oxidation and reduction technique was applied to actual 40-nm-CD device processing, the complete removal of WOx formed on the sidewall of tungsten line could be observed. [ABSTRACT FROM AUTHOR]

To address the scalability of phase change memory (PCM), we study a 1-D thickness scaling effect on threshold switching voltage (Vth), Vth drift, high resistance state (RESET) resistance (RRESET) drift, and crystallization temperature (Tcrys). We use a pseudo three-terminal device to accurately correlate the amorphous region thickness to the observed characteristics. The pseudo 3-terminal device is a fully functional PCM cell and enables 1-D thickness scaling study down to 6 nm without the need for ultrafine lithography. Vth scales down to 0.65–0.5 V (at 25 ^ \circ\C–75 ^\circ\C) for 6-nm-thick \Ge2\Sb2\Te5 (GST), showing that stable read operation is possible in scaled PCM devices. The Vth drift measurement suggests that Vth drift can be attributed to threshold switching field (Eth) drift, whereas Vth0, i.e., Vth at zero thickness, stays almost constant. RRESET drift shows no dependence on the amorphous GST thickness. Tcrys is \sim\!\175 \ ^\circ\C for the device with 6-nm-thick GST, compared with \sim\!\145 \ ^\circ\C of thick GST. From the 1-D scaling study, no significant hurdles against scaling are found down to 6 nm. Further study of scaling effect on endurance and development of scalable selection device is needed to assess the ultimate scalability of PCM. [ABSTRACT FROM PUBLISHER]

The polycrystalline thin films CeO2, W03, amorphous complex films W03 + CeO2 with content of CeO2 in the powder 10, 15 and 20 %, and CeO2 + Dy203 with content of Dy203 in the powder 10, 15 and 20 % are obtained by vacuum deposition method via powder evaporation. For the first time the optical characteristics of complex films W03 + CeO2 and CeO2+Dy203 are obtained. As a results of films investigation by ellipsometry the dependencies of refraction and extinction coefficients on incident beam energy are presented. The dielectric permittivity and energy band gapes are calculated. The refraction coefficients of films CeO2 are 1.85-2.85 and are not more than 2.37 for complex films. Dielectric constant e of complex films are 3.57-4.16, and ∊ 4.7 of CeO2 film. The CeO2, W03, and W03 + CeO2 films have wide band gape Eg = 2.8-3.37 eV. [ABSTRACT FROM AUTHOR]

Presents a table of contents for the volume 40, 2003 issue of the "Canadian Geotechnial Journal."

Examines the effect of seepage force on tunnel face under steady-state groundwater flow conditions. Parameters required for the limit analysis of tunnels; Calculation of the effective stress in front of the tunnel face; Model tests performed to simulate groundwater flow during tunnel excavation.