Characteristic Morphology and Its Properties of Melt-Crystallized Polyethylene Banded Spherulites on Scanning Electron Microscope

2001 ◽  
Vol 7 (S2) ◽  
pp. 500-501
Author(s):  
Jemyung Park ◽  
Kyuyoung Eom ◽  
Ohjun Kwon

In spite of commercial importance of polyethylene(PE), morphologies of melt crystallized PE have been rarely studied. Although, it was possible to observe polyethylene microstructure, they were based on the observation performed almost exclusively on thin films which were obtained either by casting samples between glass plates, or by microtoming the materials with transmission electron microscope(TEM). Despite the usefulness of TEM for detailed investigation of the polyethylene, it is not suitable for the structure characterization of the bulk samples, for examples, the characterization of a thick testpiece and commercial products of polyethylene itself. For such bulk specimen or thick sample, scanning electron microscope (SEM) is more useful, if the appropriate and reliable sample preparation method is applied.In this study, we introduce a chemical etching technique for the investigation of melt crystallized polyethylene microstructure by SEM. Especially in this work we studied the characteristic properties and shapes of polyethylene banded spherulite which come from the melt s.

Author(s):  
A. G. Cullis

In a previous study of impurity gettering in Si it was found that Au-containing precipitates were formed at the surfaces of wafers which had been equilibrated with Au at 1200°C and then subjected to B diffusion at 1000°C. The work reported in summary here relates to the characterization of the precipitates and to the construction of a model for their growth. This investigation involved the use of both the transmission electron microscope (TEM) and the scanning electron microscope (SEM). Full details will be reported elsewhere.


2011 ◽  
Vol 233-235 ◽  
pp. 623-626 ◽  
Author(s):  
Ling Xin ◽  
Bo Liu ◽  
Jiu Hong Ai ◽  
Jian Cheng Deng

Novel netlike nano-TiO2 was successfully prepared using polylatic acid (PLA) as a new template, and in particular, it was recyclable as photocatalyst. The products obtained at various temperatures were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM) and powder X-ray diffraction (XRD). Besides, the products have an excellent photocatalysis to methyl orange (MO) and methylene blue (MB).


Author(s):  
K. Shibatomi ◽  
T. Yamanoto ◽  
H. Koike

In the observation of a thick specimen by means of a transmission electron microscope, the intensity of electrons passing through the objective lens aperture is greatly reduced. So that the image is almost invisible. In addition to this fact, it have been reported that a chromatic aberration causes the deterioration of the image contrast rather than that of the resolution. The scanning electron microscope is, however, capable of electrically amplifying the signal of the decreasing intensity, and also free from a chromatic aberration so that the deterioration of the image contrast due to the aberration can be prevented. The electrical improvement of the image quality can be carried out by using the fascionating features of the SEM, that is, the amplification of a weak in-put signal forming the image and the descriminating action of the heigh level signal of the background. This paper reports some of the experimental results about the thickness dependence of the observability and quality of the image in the case of the transmission SEM.


Author(s):  
S. Takashima ◽  
H. Hashimoto ◽  
S. Kimoto

The resolution of a conventional transmission electron microscope (TEM) deteriorates as the specimen thickness increases, because chromatic aberration of the objective lens is caused by the energy loss of electrons). In the case of a scanning electron microscope (SEM), chromatic aberration does not exist as the restrictive factor for the resolution of the transmitted electron image, for the SEM has no imageforming lens. It is not sure, however, that the equal resolution to the probe diameter can be obtained in the case of a thick specimen. To study the relation between the specimen thickness and the resolution of the trans-mitted electron image obtained by the SEM, the following experiment was carried out.


Author(s):  
R. F. Schneidmiller ◽  
W. F. Thrower ◽  
C. Ang

Solid state materials in the form of thin films have found increasing structural and electronic applications. Among the multitude of thin film deposition techniques, the radio frequency induced plasma sputtering has gained considerable utilization in recent years through advances in equipment design and process improvement, as well as the discovery of the versatility of the process to control film properties. In our laboratory we have used the scanning electron microscope extensively in the direct and indirect characterization of sputtered films for correlation with their physical and electrical properties.Scanning electron microscopy is a powerful tool for the examination of surfaces of solids and for the failure analysis of structural components and microelectronic devices.


Author(s):  
Shaopeng Hu ◽  
Jianhua Wang ◽  
Zhen Li ◽  
Huei Chen ◽  
Fei Cu ◽  
...  

Gastritis from returning bile is a common disease, but the reason for the disease is not clear. As the pathologic ultrastructure research progresses, it has drawn attention to the ultrastructural change of cells in gastric mucosa by clinical workers. We observed gastric mucosa tissues of 15 patients suffering from gastritis with a transmission electron microscope (TEM) and a scanning electron microscope (SEM). It is the first report in China that fungus exists in the lamina propria of gastric mucosa tissue. The result is as follows.The gastric mucosa tissues of 15 patients suffering from gastritis were acquired by stomachoscopy. Both TEM and SEM specimens were prepared by the usual methods. Under the TEM, the epithelial surface became higher and larger. Mitochondria of the cells were swollen and cristae were disrupted. There were vacuoles in the cells. The nucleus showed disorder, heterochromatin became darker, and nucleolae could be observed.


Author(s):  
Gao Fengming

Transmission electron microscope(TEM) and scanning electron microscope(SEM) were widely used in experimental tumor studies. They are useful for evaluation of cellular transformation in vitro, classification of histological types of tumors and treating effect of tumors. We have obtained some results as follows:1. Studies on the malignant transformation of mammalian cells in vitro. Syrian golden hamster embryo cells(SGHEC) were transformed in vitro by ThO2 and/or ore dust. In a few days after dust added into medium, some dust crystals were phagocytized. Two weeks later, malignant transformation took place. These cells were of different size, nuclear pleomorphism, numerous ribosomes, increasing of microvilli on cell surface with various length and thickness, and blebs and ruffles(Figs. 1,2). Myelomonocytic leukemic transformation of mouse embryo cells(MEC) was induced in vitro by 3H-TdR. Transformed cells were become round from fusiform. The number of mitochondria and endoplasmic reticulum was reduced, ribosomes and nucleoli increased, shape of nuclei irregular, microvilli increased, and blebs and ruffles appeared(Fig. 3).


Author(s):  
Edward Coyne

Abstract This paper describes the problems encountered and solutions found to the practical objective of developing an imaging technique that would produce a more detailed analysis of IC material structures then a scanning electron microscope. To find a solution to this objective the theoretical idea of converting a standard SEM to produce a STEM image was developed. This solution would enable high magnification, material contrasting, detailed cross sectional analysis of integrated circuits with an ordinary SEM. This would provide a practical and cost effective alternative to Transmission Electron Microscopy (TEM), where the higher TEM accelerating voltages would ultimately yield a more detailed cross sectional image. An additional advantage, developed subsequent to STEM imaging was the use of EDX analysis to perform high-resolution element identification of IC cross sections. High-resolution element identification when used in conjunction with high-resolution STEM images provides an analysis technique that exceeds the capabilities of conventional SEM imaging.


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