We studied the trapping of positive and negative charges in the chemical structures of polymers under a high electric field using a space charge measurement system. Positive charges accumulated in low-density polyethylene (LDPE), whereas positive and negative charges accumulated in polyimide (Kapton ® ) and also in ethylene tetrafluoroethylene (ETFE) subjected to electron beam irradiation. To determine the charge-trapping sites in the chemical structures, a quantum chemical calculation was carried out using Density Function Theory (DFT) with Gaussian 09. The relationship between the energy band and the isosurface of orbital electrons at various energy levels was obtained. A threedimensional (3D) electrostatic potential distribution map was obtained for positively and negatively charged polymers to determine the relationship between a trapping site and the charge accumulation center in the 3D potential distribution map. Positive and negative charges in Kapton and ETFE films are trapped in trapping sites in chemical structures and the positive charges in an LDPE film are trapped in physical defects.

1. Phosphatase I1 is a form of phosphoprotein phosphatase originally found in rat liver extract; it has a molecular weight of 160000 by gel filtration and is highly active towards phosphorylase a. This phosphatase has been purified 1800-fold by using DEAE-cellulose (DE-52), aminohexyl-Sepharose-4B, protamine -Sepharose4B and Sephadex G-200 chromatography. Throughout the purification steps, the original molecular weight and substrate specificity of phosphatase I1 were almost perfectly preserved.2. The product of the final purification step migrated predominantly as a single protein band on non-denaturing gel electrophoresis. Sodium dodecyl sulfate gel electorphoresis revealed that the enzyme contains two types of subunit, a and p, with molecular weights of 35000 and 69000, respectively. When treated with 0.2 M 2-mercaptoethanol at -20 "C, phosphatase I1 was dissociated to release the catalytically active a subunit. The fi subunit may be catalytically inactive but interacts with the a subunit so that phosphatase I1 becomes much less susceptible than the a subunit to inactivation by ATP or pyrophosphate.

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The observation of slow-wave sustained (SW) discharge in a whistler- or helicon-wave range of frequency is made using high-frequency and very-high-frequency bands of rf. The SW discharge occurs at an extremely low rf power and plasma density, which are lower than a capacitive-coupling discharge region.

Japanese cedar was preheated at 5008C and subsequently mixed with 40 mm Al 2 O 3 particles. A pulse current heating method was used for a 5-min carbonization step under a pressure of 50 MPa in order to promote the graphitization at temperatures between 2000 and 22008C. The samples were analyzed in an analytical transmission electron microscope equipped with a GATAN Imaging Filter, in a high resolution transmission electron microscope and in a scanning electron microscope. Transformation into well-ordered graphite could be enforced by the intermediate reaction of Al 2 O 3 and carbon to plate-like Al 4 C 3. This latter compound dissociates under the proper CO pressure and temperature into Al vapor and solid graphite. The addition of Al 2 O 3 and the pressurized heating device improve the graphitization in comparison with the effect of temperature alone. The electron microscopic observations are supported by XPS and XRD spectra.

This paper presents a micro-coordinate measuring machine (micro-CMM) for large-scale dimensional measurement of a micro-slit on a precision die coater by using a shear-mode micro-probe. A glass micro sphere with a nominal diameter of 52.3 µm was attached on one end of a tapered glass capillary tube as a probe tip ball. The micro-slit width of a slot die coater with a nominal slit width of 85 µm was measured by the micro-CMM. The probe tip was placed in the slit for the measurement. The effective working length of the probe was confirmed experimentally to be at least 1 mm. In order to measure the gap width uniformity over the entire slot die length of 200 mm, an air-bearing linear slide with a travelling stroke of 300 mm was employed in the micro-CMM to position the probe along the length direction of the slot die. The angular alignment error and the motion error of the air-bearing linear slide as well as those of the stages for positioning the probe along the direction perpendicular to the length direction of the slot die were investigated for evaluation of the expanded uncertainty of gap width measurement.

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The US Department of Energy's Basic Energy Sciences Office published a report entitled, "Future Electron Scattering and Diffraction" in 2014. In the report, it listed the "Lab-in-gap" dynamic microscope as one of the major instrumentation needs for enabling breakthrough scientific opportunities. Specifically, it called for sample stage and holder designs that would allow advanced in situ analyses [1]. We have recently manufactured a MEMS-based heating and electric bias holder that fits into the sample stage of the newly developed 200-kV Hitachi HF5000 transmission electron microscope. The new sample stage enables a wider, jewel-less sample holder design, providing a larger platform which is advantageous for laying out electric contacts and transportation of stimuli. As shown in Fig. 1a, the Hitachi "Blaze" Heating Holder comes with the MEMS-based heating chips, which are SiN membranes sandwiching a heating element, manufactured by Norcada Inc. The contact pad to the heating chip is a replaceable. Simulated temperature profiles at 850 and 1100 o C indicated the central 160 µm-diameter is isothermal (Figs.1b and 1c). At the center of the isothermal region, there are 19 sample wells in 5 arrays. These sample wells have a 30 nm-thick SiN support film, providing electron transparency and exceptional chemical, thermal and mechanical stability.In this paper, we report the in situ heating study of lunar and planetary materials using the Blaze heating holder [2]. The lunar soil samples were acquired from the Apollo 14 and 17 missions. To prepare the samples for in situ heating, we suspended particles in methanol and then transferred them onto the heating chip using a micro pipette. We analyzed the samples after the methanol had completely evaporated. Part of the heating study was carried out using the 300 kV Hitachi HF3300 TEM/STEM located at the University of Toronto. Complementary work is also being pursued with in-depth heating studies in the probe-corrected 200 kV Hitachi HF5000 TEM/STEM at the University of Arizona. Both microscopes are equipped with a secondary electron (SE) detector, which allow simultaneous secondary and transmitted election imaging to obtain the information from the surface (SEM) and bulk (annular dark field (ADF) and bright field (BF) of the lunar soil particles. Figure 2 documents the structural evolution of one particle before and after a total of eight thermal shocks with 1-sec duration over a temperature range from 20 to 940 o C. Iron nanocrystals developed on the surface of the grain after the first thermal shock and continued to increase in size with each subsequent heat treatment. EELS analysis (not shown) further confirms the metallic nature of these iron nanocrystals.In summary, the Blaze heating holder is proven to have enabled simulation of heating events occurred on airless bodies such as lunar and planetary materials. It can also be used to address questions on thermal annealing of ceramics and nanostructured materials [3].