Analysis of read-out operation in 1T2C-type ferroelectric memory cell

Abstract

A 1T2C-type ferroelectric memory cell, in which two ferroelectric capacitors with the same area are connected to the gate of an usual MOSFET with a SiO₂/Si interface, was fabricated and characterized. It was found that the memory window significantly changed by the device parameters, which means that the low voltage operation is possible if we optimize these parameters. The fabricated cell, is composed of a stacked gate structure of Pt/SBT/Pt/Ti/SiO₂/Si with the area ratio of the MOS capacitor to the ferroelectric capacitor of 6 or 10. Nonvolatile memory operation was confirmed, in which the current on/off ratio was larger than 3-order-of magnitude and the data retention time was longer than 6 × 10⁴ seconds.     

Process for recycling waste aluminum with generation of high-pressure hydrogen

An innovative environmently friendly hydrolysis process for recycling waste aluminum with the generation of high-pressure hydrogen has been proposed and experimentally validated. The effect of the concentration of sodium hydroxide solution on hydrogen generation rate was the main focus of the study. In the experiments, distilled water and aluminum powder were placed in the pressure-resistance reactor made of Hastelloy, and was compressed to a desired constant water pressure using a liquid pump. The sodium hydroxide solution was supplied by liquid pump with different concentrations (from 1.0 to 5.0 mol/dm3) at a constant flow rate into the reactor by replacing the distilled water, and the rate of hydrogen generated was measured simultaneously. The liquid temperature in the reactor increased due to the exothermic reaction given by Al + OH(-) + 3H2O = 1.5H2 + Al(OH)4(-) + 415.6 kJ. Therefore, a high-pressure hydrogen was generated at room temperature by mixing waste aluminum and sodium hydroxide solution. As the hydrogen compressor used in this process consumes less energy than the conventional one, the generation of hydrogen having a pressure of almost 30 MPa was experimentally validated together with Al(OH)3, a useful byproduct.     

Oral administration of bovine lactoferrin attenuates ultraviolet B-induced skin photodamage in hairless mice

Lactoferrin (LF) is recognized as a host defensive glycoprotein, especially for newborn infants. The aim of this study was to investigate whether orally administered LF had protective activity against UV-induced skin damage in hairless mice. Transepidermal water loss and skin hydration were evaluated in nonirradiated mice, UVB-irradiated mice, and UVB-irradiated and LF-administered mice. Supplementation with LF (1,600 mg/kg per day) effectively suppressed the increase in transepidermal water loss, reduction in skin hydration, aberrant epidermal hyperplasia, and cell apoptosis induced by UV irradiation. Although no significant changes in superoxide dismutase-like activity or malondialdehyde levels were observed in the skin with both UV irradiation and LF administration, UV-stimulated IL-1β levels in the skin were significantly suppressed by the administration of LF. Oral supplementation with LF has the potential to reduce IL-1β levels and prevent UV-induced skin damage. Further studies are needed to elucidate the relationships between the antiinflammatory effects and skin protective function of LF.     

Processing of XynE (110-kDa) of Aeromonas caviae ME-1 to 72-kDa xylanase in Escherichia coli transformant

An extracellular 72-kDa xylanase from an Escherichia coli transformant that harbored pXED30 carrying xynE of Aeromonas caviae ME-1 was purified by extraction following SDS-PAGE to electrophoretic homogeneity. The analysis of N-terminal 10 amino acid residues (Gly-Ala-Arg-Ala-Gln-Ala-Ala-Ala-Asp-Val) revealed a 72-kDa product derived by the cleavage of Gly26-Gly27 at the N-terminal region of 110 kDa XynE. The 72-kDa xylanase from A. caviae ME-1 was found to have the same sequence as that of the N-terminal 10 amino acid residues. When OmpT-deficient E. coli mutants were used as hosts, the 72-kDa xylanase was detected in cell-free extracts, but not in the culture supernatant, suggesting that OmpT is not involved in the cleavage at the C-terminal region, but is involved in the secretion of 72-kDa xylanase to the culture medium.     

Determination of pindone in agricultural products by LC-MS/MS

A sensitive and selective analytical method for the determination of pindone in agricultural products by LC-MS/MS was developed. Pindone was extracted with acetone, and an aliquot of the crude extract was re-extracted with hexane. For lipid-rich samples, the crude extract was further cleaned up by acetonitrile-hexane partitioning. The extract was cleaned up on a tandem graphitized carbon-silica gel column. For brown rice, soybean, and tea, PSA column cleanup was added prior to LC-MS/MS determination. Average recoveries of pindone from brown rice, soybean, potato, spinach, cabbage, apple, orange, tomato, cucumber, and tea fortified at 0.001 mg/kg were 81-93%, and the relative standard deviations were 2-7%. The limit of quantitation (S/N ≥ 10) of the developed method was 0.001 mg/kg for all the tested agricultural products.     

Numerical Study of Effects of Scattering Processes on Transport Properties of Bi Nanowires

In this study, we investigated the effects of scattering on the transport properties of Bi nanowires. The electrical conductivities and Seebeck coefficients of Bi nanowires were calculated using the Boltzmann equation, with an energy-dependent relaxation time corresponding to the scattering process. Decreasing the wire diameter increased the Seebeck coefficient for all of the scattering processes examined, because a semimetal–semiconductor transition occurred. In 80-nm-diameter nanowires, the Seebeck coefficient for ionized impurity scattering was larger than that of the acoustic deformation potential. On the other hand, in 20-nm-diameter nanowires, the dependence of the Seebeck coefficient on the scattering process was negligible, compared with the influence of wire diameter.     

Effect of TiC and NbC carbides on creep life of stainless steels

The effect of TiC and NbC carbides on creep life has been investigated for 321HTB and 347HTB steels at 600–750°C for about 20–200,000 h. The creep data for 304HTB steel are used as reference data. The precipitation hardening is larger for the 321HTB than for the 347HTB at short times during creep. Then the reduction of precipitation hardening due to coarsening of TiC and NbC carbides takes place for up to long times, which is less significant in the 321HTB than in the 347HTB. The smaller coarsening rate of the TiC carbides than the NbC carbides during creep is discussed on the base of a rate equation for diffusion-controlled Ostwald ripening.     

cBN烧结体工具的最新动向及其适用事例

通过特殊陶瓷黏结材料将cBN粒子烧结成专用于淬火钢加工的cBN烧结工具是在1977年被首次开发出来的.自产品化以来,cBN烧结体工具在以淬火钢为主的铁类难切削材料的切削加工方面被广泛应用.由于cBN烧结体工具与传统的超硬以及金属陶瓷、陶瓷工具相比较具有加工使用寿命长的优点,现在其使用范围正在扩大.在淬火钢切削领域,由于...     

High-Intensity Ultrasound-Induced Crystallization of Mango Kernel Fat

The crystallization behavior of mango kernel fat (MKF) at 25 °C with and without the application of high-intensity ultrasound (HIU) (20 kHz, 125 W) was studied as a function of ultrasound amplitude level (30%, 50%, and 70% of the maximum amplitude of 180 μm). The irradiation period was fixed at 5 s. It was found that HIU induced MKF crystallization. The crystallization induction time decreased with a decrease in crystal size and an increase in the number of crystals as the HIU amplitude increased. The β' → β transformation was also accelerated with HIU application. This work has shown that there is great potential for the use of HIU in the food industry to achieve a shorter and more controllable crystallization process. In particular, HIU could be used as an efficient tool for controlling the polymorphic transition of fats.