Ionic liquid enables simple and rapid sample preparation of human culturing cells for scanning electron microscope analysis

Ionic liquid is a kind of salt that stays in a molten state even at room temperature. It does not vaporize at all in vacuum and facilitates electrical conductivity to the sample surfaces for observations with a scanning electron microscope (SEM). In this study, we used an ionic liquid in SEM for the first time to observe fixed human culture cells. The condition for the cell culture using wrapping sheets and SEM settings were varied to elucidate the optimized protocol. Compared to samples prepared by the conventional way, the ionic liquid‐treatment of samples gave SEM images of the cellular ultra structures in more detail, enabling observation of microvilli that made bridges between separated cells. In addition, the ionic liquid treatment is less time consuming as well as less laborious compared with the conventional way that includes dehydration, drying, and conductivity treatments. Totally, we concluded the ionic liquid is a useful reagent for SEM sample preparation. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.     

电子装置内的热移动研究——温度分布及速度分布

在高60cm,宽45cm 的模拟电子装置内,进行装置内热移动研究,得到不同条件下的温度分布及速度分布.在理论解析及数值计算基础上,进行无因次准数关联,得出实验式.实验结果及解析结果基本一致.利用所得实验式对正在运转或有待开发的新的电子装置有关参数进行推算,对于传热设计具有很强的实用性.     

Two-wavelength laser diode interferometer with time-sharing sinusoidal phase modulation

We describe an interferometer system that uses two separate wavelengths to measure step height. The overlapping interference images detected by a CCD camera are easily separated by an ordinary integrating-bucket method and time-sharing sinusoidal phase modulation, in which two laser diodes are alternately modulated with a sinusoidal signal. A phase map is obtained only for the laser diode into which the modulation signal is injected. In this instance, a 1-microm step height was accurately detected.     

Surface modification of an organosilane self-assembled monolayer on silicon substrates using atomic force microscopy: scanning probe electrochemistry toward nanolithography

Organosilane self-assembled monolayers (SAMs) have been applied to resist materials for nanolithography based on scanning probe microscopy. An organosilane SAM was prepared on Si substrates from a precursor, that is octadecyltrimethoxysilane. Using an atomic force microscope with a conductive probe, current was injected from the probe into the SAM-covered Si substrate so that the SAM was locally degraded at the probe-contacting point. Nanoscale patterns drawn on the SAM was clearly imaged by lateral force microscopy. The patterning could be conducted in air while, in vacuum at the order of 10(-6) Torr, no detectable patterns were fabricated. The presence of adsorbed water at the probe/sample junction was confirmed to be crucial for the patterning of the SAM/Si. Its mechanism was, thus, ascribed to electrochemical reactions of both the SAM and Si with adsorbed water.     

Fast incremental learning methods inspired by biological learning behavior

Model-based learning systems such as neural networks usually “forget” learned skills due to incremental learning of new instances. This is because the modification of a parameter interferes with old memories. Therefore, to avoid forgetting, incremental learning processes in these learning systems must include relearning of old instances. The relearning process, however, is time-consuming. We present two types of incremental learning method designed to achieve quick adaptation with low resources. One approach is to use a sleep phase to provide time for learning. The other one involves a “meta-learning module” that acquires learning skills through experience. The system carries out “reactive modification” of parameters not only to memorize new instances, but also to avoid forgetting old memories using a meta-learning module.This work was presented, in part, at the 9th International Symposium on Artificial Life and Robotics, Oita, Japan, January 28–30, 2004     

Thermodynamics of iron oxide in Fe x O-dilute CaO + Al2O3 + MgO + Fe x O slags at 1873 K

In order to determine the ferrous and ferric ion capacities: 3

Efficient construction of cDNA microarrays utilizing normalized cDNA libraries of Arabidopsis thaliana

We have demonstrated the utility of normalization for efficient cDNA microarray preparation using Arabidopsis as a model. Nonredundant cDNAs including 5722 species were efficiently collected from random 7914 expressed sequence tags (ESTs) in four normalized cDNA libraries. The prepared microarrays were successfully used to monitor gene expression. These methodologies should be applicable to the study of other species in plant biotechnology.     

Photovoltaic characteristics of TCNQ-incorporated CuPc-poly(p-phenylene) composite films

Composite films (CuPc–PPP–TCNQ) were produced by simultaneous deposition using copper phthalocyanine (CuPc) as a carrier generation material, poly(p-phenylene) (PPP) as a hole transport material, and tetracyanoquinodimethane (TCNQ) as a incorporation material. Schottky barrier photovoltaic cells, consisting of a semitransparent aluminum and the CuPc–PPP–TCNQ composite films, were fabricated. The junction properties and the photovoltaic properties on Al/CuPc–PPP–TCNQ/ITO sandwich cells were investigated. As well as a composite film of the CuPc and the PPP (CuPc–PPP), the conductivity of the CuPc–PPP–TCNQ composite film is improved as the TCNQ is simultaneously deposited in the CuPc–PPP composite film. Therefore, it is proven that the short circuit photocurrent density (J _sc) and the photovoltaic property increases significantly. The J _sc of the Al/CuPc–PPP–TCNQ/ITO cell is 2.60 A/cm², and it is found that the J _sc is about 20 times that of an Al/CuPc/ITO cell and double that of an Al/CuPc–PPP/ITO cell. Consequently, the power conversion efficiency of the Al/CuPc–PPP–TCNQ/ITO cell obtained was 3.68%.     

Lattice parameter determination of a strained area of an InAs layer on a GaAs substrate using CBED

All the six lattice parameters (a, b, c, alpha, beta and gamma) of a strained area of an InAs layer grown on a GaAs substrate were determined without any assumption of the crystal lattice symmetry from the higher-order Laue zone (HOLZ) lines appearing in one convergent-beam electron diffraction (CBED) pattern. The analysis was performed with three steps. Firstly, the parameters alpha and beta were determined from the deviations of the HOLZ lines from the mirror symmetry perpendicular to the [001] direction. Secondly, the parameter c was determined from the distance between the intersections of the HOLZ lines, which have the same h and k indices but different l indices. Finally, the parameters a, b and gamma were determined simultaneously from several distances between the intersections of the HOLZ lines. The lattice parameters determined for the strained area were a = 0.611(2) nm, b = 0.615(1) nm, c = 0.6119(7) nm, alpha = 89.5(1) degrees, beta = 89.0(2) degrees and gamma = 89.1(2) degrees. This result implies that the cubic lattice of InAs is elongated approximately in the [111] direction and the exact lattice symmetry is triclinic. The same analysis procedure was applied to another two specimen areas. It was found that the areas have orthorhombic distortions with lattice parameters a = 0.607(2) nm, b = 0.604(1) nm and c = 0.6085(7) nm for one area, and with a = 0.607(2) nm, b = 0.605(1) nm and c = 0.6065(7) nm for the other area. It is should be emphasized that the present analysis of lattice distortions is immediately applicable to the other semiconductors, such as Si, SiGe or GaAs layers, without assuming any crystal system.