摘要:

SUMMARYA beam‐deflection type laser scanning microscope for differential phase contrast images using the split‐detector technique is developed and the images are obtained in real time (30 images/s).The special optical design allows transfer of the pupil information necessary to the imaging of the differential phase contrast images during beam deflection and the use of acousto‐optic deflectors with the associated correction system enables real time imaging.Differential phase images of surface details of crystals are simply obtained without silver coating or etching, which are indispensable in a normal DIC. Biological specimens are also obs

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1987.tb02850.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SUMMARYAn extremely simple, modified polanret phase‐contrast system has been developed. It uses only a single polarizing ring, instead of three zonal polarizers as required in Osterberg's original polanret system (manufactured by the American Optical Corporation). The modified system is much more easily manufactured and its economy of light is twice as good. However, it does require an easily accessible microscope objective exit pupil, where the polarizing ring must be locate

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1987.tb02851.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SUMMARYThe scanning acoustic microscope is a valuable tool for the ultrasonic non‐destructive testing of ceramic materials or sintered metals, like titanium compounds. Bulk defects, responsible for the mechanical aging and breakdown of parts, are easily detected and imaged. Moreover, diffuse structures are evidenced in these images, forming a continuous background. In this paper, we present a method which enables the determination of physical parameters, like the density and the bulk grain size of the materials, from this background. This information is extracted, using a statistical approach, from the histograms pertaining to materials with a spectrum of different microstructures, based on a principal component analysis (PCA). It may be noted that the size of the microstructure elements accessible by this method can be lower than the spatial resolution of the microscop

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1987.tb02852.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SUMMARYThe phase Al3Fe (monoclinicC2/m, a= 1·549 nm,b= 0·808 nm,c= 1·248 nm, β = 107·8°) has been studied by transmission electron microscopy (TEM) and high resolution electron microscopy (HREM). Crystals were obtained from a direct chill‐cast ingot of an Al‐0·25 wt% Fe‐0·13 wt% Si alloy. Extracted crystals were prepared by dissolving the aluminium phase in butanol and filtering off the particles. The extracted Al3Fe crystals were mainly (100) platelets. The monclinic lattice was confirmed by tilt experiments and the mirror plane was confirmed by convergent beam electron diffraction. Experimental HREM images from the [100] and [110]projection agreed with images calculated by the multislice method. The interpretation of images in terms of a projected crystal structure is discussed. Common defects in Al3Fe crystals were: twins on (100) and faults on (001). The (001) faults could be described by a displacement 1/2·[100] on a fault plane atz= 0·5 in the unit cell. A model for (001) faults, based on multiple twinni

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1987.tb02853.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SUMMARYLISPIX is an image processing and analysis system consisting of a sub‐system of image processing commands implemented in FORTRAN and a collection of analysis algorithms implemented in LISP. Examples are given of using the system for microanalysis applications. The processing commands are useful alone for simple tasks. For analysis applications, the LISP programming environment, for which the processing commands are designed, allows rapid development of algorithms and a convenient way to use them. Appendices contain definitions of the most useful commands as well as examples of the LISP algorithm

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1987.tb02854.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SUMMARYA method is described in which quick‐frozen, freeze‐substituted, cultured cells can be prepared for whole‐cell transmission electron microscopy (WCTEM). This method is simple and reliable and can be carried out in most laboratories without special equipment. Cells grown on Formvar‐carbon‐coated nickel grids are quick‐frozen in Freon 22, freeze‐substituted in an ethanolic solution of glutaraldehyde, post‐fixed in osmium tetroxide and critical‐point‐dried. The quality of ultrastructural preservation using this ‘double fixation’ protocol is comparable to that of conventional WCTEM. However, the combination of quick‐freezing and WCTEM has the decided advantage over conventional WCTEM in that cellular activities are arrested almost instantaneously. Thus, this new method could potentially yield a more faithful representation of cytoarchitecture and is especially useful for studies on the structural basis of rapid cytoplasmic events which may remain undetected when using conv

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1987.tb02855.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SUMMARYA simple new method of deep‐etching, ‘upside‐down etching’, has been developed in an attempt to obtain clearer images or replicas, especially of fresh, untreated biological tissues. During etching, specimens were kept facing downwards and shaken periodically so that non‐volatile materials in the subliming ice could fall out of the frozen tissue. This improvement leads to a considerable reduction of sedimented debris of unetchable materials on ‘true’ membrane surfaces, as well as in the cytoplasm exposed by

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1987.tb02856.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SUMMARYA new design for interlocking specimen support cups that permits reliable and reproducible freezing under high pressures of a range of different biological specimens is described. A stronger holder in which the support cups are tightly held during pressurization and freezing, and a sliding wedge for separating the cups after freezing are also described. Used in conjunction with the Balzers HPM 010 high pressure freezing apparatus, these modifications permit routine freezing of tissue for freeze‐fracture and freeze‐substitution for electron microsc

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1987.tb02857.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SUMMARYThe exact measurement of the thickness of semi‐thin and ultra‐thin sections is of importance for some stereological methods. Although section thickness can be measured with great precision and accuracy using suitable microinterferometers, such instruments are expensive and not easily available to many laboratories. This paper describes a simple method of measuring the thickness of sections actually used for stereological counting procedures. It involves the division of any given section into two portions, one of which is used for the counting procedures. The other portion is re‐embedded and re‐sectioned through its thickness making it a simple task to measure its th

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1987.tb02858.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SUMMARYA new method based on the simultaneous action of Safranin and Alcian Blue (or green) is reported. The main advantages of this method are its simplicity and the absence of differentiation processes. Free‐hand, frozen and paraffin sections can be stained with this technique. Sections are placed in 10% sodium hypochlorite for 1–5 min, rinsed in 5% acetic acid and stained for 10 min. Sections are then washed in distilled water for 1 min, rinsed in distilled water for 5 min and moun

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1987.tb02859.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY