scholarly journals Microscopic observation of the segmental orientation autocorrelation function for entangled and constrained polymer chains

2017 ◽  
Vol 146 (9) ◽  
pp. 094902 ◽  
Author(s):  
Anton Mordvinkin ◽  
Kay Saalwächter
Keyword(s):  
Autocorrelation Function ◽  
Microscopic Observation ◽  
Polymer Chains ◽  
Segmental Orientation

Effect of excluded volume on segmental orientation correlations in polymer chains

2008 ◽  
Vol 78 (5) ◽  
Author(s):  
Jens-Uwe Sommer ◽  
Walter Chassé ◽  
Juan López Valentín ◽  
Kay Saalwächter
Keyword(s):  
Polymer Chains ◽  
Excluded Volume ◽  
Segmental Orientation

Electron Microscopic Observation of the Longitudinal Organization of Poly (p-Phenylene Terephthalamide) Fibers

1982 ◽  
Vol 40 ◽  
pp. 680-681
Author(s):  
Li Li-Sheng ◽  
L.F. Allard ◽  
W.C. Bigelow
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Microscopic Observation ◽  
Electron Microscopic Observation ◽  
Electron Microscopic ◽  
Aromatic Polyamides ◽  
Radial Arrangement ◽  
Scanning Electron ◽  
Better Than

The aromatic polyamides form a class of fibers having mechanical properties which are much better than those of aliphatic polyamides. Currently, the accepted morphology of these fibers as proposed by M.G. Dobb, et al. is a radial arrangement of pleated sheets, with the plane of the pleats parallel to the axis of the fiber. We have recently obtained evidence which supports a different morphology of this type of fiber, using ultramicrotomy and ion-thinning techniques to prepare specimens for transmission and scanning electron microscopy.

Qualitative study on “hydropic degeneration” of The hepatocytes in viral hepatitis

1990 ◽  
Vol 48 (3) ◽  
pp. 568-569
Author(s):  
Le Meizhao ◽  
Ye Ming ◽  
Song Xiaoming ◽  
Xu Jiazhang
Keyword(s):  
Qualitative Study ◽  
Viral Hepatitis ◽  
Chronic Active Hepatitis ◽  
Microscopic Observation ◽  
Hydropic Degeneration ◽  
Light Microscopic Observation ◽  
Biopsy Specimens ◽  
Endoplasm Reticulum ◽  
Mixed Fluid ◽  
Peripheral Cytoplasm

“Hydropic degeneration” of the hepatocytes are often found in biopsy of the liver of some kinds of viral hepatitis. Light microscopic observation, compareted with the normal hepatocytes, they are enlarged, sometimes to a marked degree when the term “balloning” degeneration is used. Their cytoplasm rarefied, and show some clearness in the peripheral cytoplasm, so, it causes a hydropic appearance, the cytoplasm around the nuclei is granulated. Up to the present, many studies belive that main ultrastructural chenges of hydropic degeneration of the hepatocytes are results of the RER cristae dilatation with degranulation and disappearance of glycogen granules.The specimens of this study are fixed with the mixed fluid of the osmium acidpotassium of ferricyanide, Epon-812 embed. We have observed 21 cases of biopsy specimens with chronic severe hepatitis and severe chronic active hepatitis, and found that the clear fields in the cytoplasm actually are a accumulating place of massive glycogen. The granules around the nuclei are converging mitochondria, endoplasm reticulum and other organelles.

Ultrastructural Localization Study of Carcinoembryonic Antigen (CEA) in Gastric Cancer: Immunoelectron Microscopic Observation

1990 ◽  
Vol 48 (3) ◽  
pp. 252-253
Author(s):  
Dong Yuming ◽  
Yang Guanglin ◽  
Wu Jifeng ◽  
Chen Xiaolin
Keyword(s):  
Gastric Cancer ◽  
Intestinal Metaplasia ◽  
Cancer Cells ◽  
Microscopic Observation ◽  
Biological Significance ◽  
Ultrastructural Localization ◽  
Mucinous Carcinoma ◽  
Surface Glycoprotein ◽  
Tubular Adenocarcinoma ◽  
Pap Method

On the basis of light microscopic observation, the ultrastructural localization of CEA in gastric cancer was studied by immunoelectron microscopic technique. The distribution of CEA in gastric cancer and its biological significance and the mechanism of abnormal distribution of CEA were further discussed.Among 104 surgically resected specimens of gastric cancer with PAP method at light microscopic level, the incidence of CEA(+) was 85.58%. All of mucinous carcinoma exhibited CEA(+). In tubular adenocarcinoma the incidence of CEA(+) showed a tendency to rising with the increase of degree of differentiation. In normal epithelia and intestinal metaplasia CEA was faintly present and was found only in the luminal surface. The CEA staining patterns in cancer cells were of three types--- cytoplasmic, membranous and weak reactive type. The ultrastructural localization of CEA in 14 cases of gastric cancer was studied by immunoelectron microscopic technique.There was a little or no CEA in the microvilli of normal epithelia. In intestinal metaplasia CEA was found on the microvilli of absorptive cells and among the mucus particles of goblet cells. In gastric cancer CEA was also distributed on the lateral and basal surface or even over the entire surface of cancer cells and lost their polarity completely. Many studies had proved that the alterations in surface glycoprotein were characteristic changes of tumor cells. The antigenic determinant of CEA was glycoprotein, so the alterations of tumor-associated surface glycoprotein opened up a new way for the diagnosis of tumors.

Log-log scale roughness spectroscopy of surfaces

1993 ◽  
Vol 51 ◽  
pp. 224-225
Author(s):  
P. Fraundorf ◽  
B. Armbruster
Keyword(s):  
Power Spectrum ◽  
Autocorrelation Function ◽  
Power Spectra ◽  
Scanning Force Microscopy ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Force Microscopy ◽  
Scanning Force ◽  
Lateral Structure ◽  
Scale Roughness

Optical interferometry, confocal light microscopy, stereopair scanning electron microscopy, scanning tunneling microscopy, and scanning force microscopy, can produce topographic images of surfaces on size scales reaching from centimeters to Angstroms. Second moment (height variance) statistics of surface topography can be very helpful in quantifying “visually suggested” differences from one surface to the next. The two most common methods for displaying this information are the Fourier power spectrum and its direct space transform, the autocorrelation function or interferogram. Unfortunately, for a surface exhibiting lateral structure over several orders of magnitude in size, both the power spectrum and the autocorrelation function will find most of the information they contain pressed into the plot’s origin. This suggests that we plot power in units of LOG(frequency)≡-LOG(period), but rather than add this logarithmic constraint as another element of abstraction to the analysis of power spectra, we further recommend a shift in paradigm.

Shape of Confined Polymer Chains

1997 ◽  
Vol 7 (3) ◽  
pp. 433-447 ◽  
Author(s):  
C. E. Cordeiro ◽  
M. Molisana ◽  
D. Thirumalai
Keyword(s):  
Polymer Chains ◽  
Confined Polymer ◽  
Confined Polymer Chains

Dynamics of polymer chains trapped in a slit

1977 ◽  
Vol 38 (10) ◽  
pp. 1285-1291 ◽  
Author(s):  
F. Brochard
Keyword(s):  
Polymer Chains

A Device for the Production of Well-Defined Lesions of Mesenteric Blood Vessels with Resulting Platelet Thrombi

1966 ◽  
Vol 15 (03/04) ◽  
pp. 471-475 ◽  
Author(s):  
K Reber
Keyword(s):  
Blood Vessels ◽  
Microscopic Observation ◽  
Electric Stimulation ◽  
Platelet Thrombi ◽  
Reproducible Manner

SummaryWell-defined lesions of mesenteric blood vessels with resulting platelet thrombi are produced in a reproducible manner by electric stimulation with a microelectrode under microscopic observation. The apparatus used and the results obtained are described.

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