Electron microscopy history

The history of EM (for an overview see table Bl.17,1) can be interpreted as the development of two concepts the electron beam either illuminates a large area of tire sample ( flood-beam illumination , as in the typical transmission electron microscope (TEM) imaging using a spread-out beam) or just one point, i.e. focused to the smallest spot possible, which is then scaimed across the sample (scaiming transmission electron microscopy (STEM) or scaiming electron microscopy (SEM)). In both situations the electron beam is considered as a matter wave interacting with the sample and microscopy simply studies the interaction of the scattered electrons. 

Electron microscopy, 16 464, 487-495 history of, 16 487-488 in polymer blend morphology determination, 20 339-340 of PVC particles, 25 658-659 of silica, 22 371-372 in surface and interface imaging, 24 75-80... 

History. Braun and Tschemak [23] obtained phthalocyanine for the first time in 1907 as a byproduct of the preparation of o-cyanobenzamide from phthalimide and acetic anhydride. However, this discovery was of no special interest at the time. In 1927, de Diesbach and von der Weid prepared CuPc in 23 % yield by treating o-dibromobenzene with copper cyanide in pyridine [24], Instead of the colorless dinitriles, they obtained deep blue CuPc and observed the exceptional stability of their product to sulfuric acid, alkalis, and heat. The third observation of a phthalocyanine was made at Scottish Dyes, in 1929 [25], During the preparation of phthalimide from phthalic anhydride and ammonia in an enamel vessel, a greenish blue impurity appeared. Dunsworth and Drescher carried out a preliminary examination of the compound, which was analyzed as an iron complex. It was formed in a chipped region of the enamel with iron from the vessel. Further experiments yielded FePc, CuPc, and NiPc. It was soon realized that these products could be used as pigments or textile colorants. Linstead et al. at the University of London discovered the structure of phthalocyanines and developed improved synthetic methods for several metal phthalocyanines from 1929 to 1934 [1-11]. The important CuPc could not be protected by a patent, because it had been described earlier in the literature [23], Based on Linstead s work the structure of phthalocyanines was confirmed by several physicochemical measurements [26-32], Methods such as X-ray diffraction or electron microscopy verified the planarity of this macrocyclic system. Properties such as polymorphism, absorption spectra, magnetic and catalytic characteristics, oxidation and reduc-... 

F. O. Schmitt, The Never-Ceasing Search, chap. 9 C. E. Hall, Recollections from the early years Canada - USA, Advances in Electronics and Electron Physics, Supplemental 16 (1985) 275-296, and N. Rasmussen Making a machine instrumental RCA and the wartime beginnings of biological electron microscopy, Studies in the History and Philosophy of Science 27 (1996) ... 

It has been shown how various factors can affect the appearance of XRD patterns and how the subtle differences in those patterns can be used to gain valuable structural and characterization information. It is clear that in order to understand a material and define it properly, all of these factors must be examined carefully. Techniques in addition to XRD, particularly electron microscopy, but also sorption and spectroscopy, should be utilized when attempting to understand the nature of a new catalyst material. Finally, it must be recognized that published XRD powder data for a given material can tell much about its structural nature but, to interpret the XRD data properly, it is also necessary to be aware of sample history, data collection parameters, morphology, etc. In short, one must know as much as possible about the various factors that affect the x-ray diffraction characteristics of catalyst materials. 

A 12-year-old boy with a history of a generalized pruritic rash after penicillin took penicillamine up to 500 mg/day for Wilson s disease. He had a rash after using penicillamine for 1 week. The penicillamine was stopped for 3 days. He developed nephrotic syndrome 2 weeks after restarting penicillamine. On electron microscopy, there was the typical picture of minimal change disease with extensive foot process effacement. 

Technical examination of objects coated with a protective covering derived from the sap of a shrubby tree produces information that can be used to determine the materials and methods of manufacture. This information sometimes indicates when and where the piece was made. This chapter is intended to present a brief review of the raw material urushi, and the history and study of its use. Analytical techniques have included atomic absorption spectroscopy, thin layer chromatography, differential thermal analysis, emission spectroscopy, x-ray radiography, and optical and scanning electron microscopy these methods and results are reviewed. In addition, new methods are reported, including the use of energy dispensive x-ray fluorescence, scanning photoacoustical microscopy, laser microprobe and nondestructive IR spectrophotometry. 

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