scholarly journals Analiza SEM czarnego tonera na wydrukach. Część II

2021 ◽  
Vol 13 (24) ◽  
pp. 221-249
Author(s):  
Anna Łasińska

Eksperci w zakresie badań dokumentów są często proszeni o określenie, czy wydruk pochodzi z określonej drukarki laserowej. Drukarkę rzadko można zidentyfikować, chyba że na wydruku są widoczne jej unikalne wady lub nieprawidłowości. W artykule przedstawiono możliwości identyfikacji i weryfikacji tonerów na wydrukach uzyskanych z rożnych drukarek laserowych przy użyciu skaningowej mikroskopii elektronowej. W sumie 21 wydruków uzyskano z 21 rożnych modeli maszyn drukujących Brother i Konica Minolta. Szesnaście wydruków uzyskano z drukarek, w których były oryginalne kasety z tonerem, a pięć z drukarek z zamiennikami. Ustalono jasne kryteria oceny indywidualnej. Na podstawie zdjęć SEM oraz tych kryteriów ujawniono szczegóły topografii struktury tonera. Na podstawie przeprowadzonych badań określono różnice lub podobieństwa tonerów na badanych wydrukach. SEM analysis of black toner on printouts. Part II Document examiners are frequently asked to determine whether or not a printout originated from a particular laser printer. The printer can rarely be identified unless some unique defects or irregularities of the printing are present on the printout. This article presents an overview of a systematic approach to characterizing and discriminating the toner of different laser printers using scanning electron microscopy. A total of twenty-one collected printouts were printed on twenty-one different Brother and Konica Minolta printing machine models. Sixteen printouts were obtained using printers with original toner cartridges while five printouts were obtained using printers with compatible cartridges. Clear criteria were established for individual assessment. Based on the SEM images and established criteria the details of topography of the toner structure were revealed. Due to this study, the differences or similarities of toners on tested printouts were determined. The SEM technique can be successfully, simply, and rapidly applied to the analysis of toners on paper documents.

2021 ◽  
Vol 05 (04) ◽  
pp. 1-1
Author(s):  
Jane Anastassopoulou ◽  
◽  
Ioannis Mamarelis ◽  
Theophile Theophanides ◽  
◽  
...  

In the present study, Fourier-transform infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM) were used to investigate the formation and development of carotid artery atherosclerosis. The FTIR spectra showed that with the progression of atheromatic plaque formation, the collagen changed its native structure from ɑ-helix to random coil, amyloid, and cross-links. The infrared spectra and SEM analysis of carotid arteries showed that higher than 65% of the atheromatic plaque in patients with stenosis consisted of calcium carbonate, which lies inside foam cells. However, as the stenosis progresses, these deposits of calcium phosphate become more prevalent. A thorough analysis of the SEM images highlighted that mineral deposits preferred the carboxyl groups of amino acids. The intensity and shape changes in FT-IR spectra in the region of 1200-900 cm<sup>-1</sup> were related to elevated serum glucose and uric acid levels, the formation of advanced glycation end products (AGEs), and the involvement of free radicals during atherosclerosis.


Author(s):  
M.E. Lee ◽  
A. Moller ◽  
P.S.O. Fouche ◽  
I.G Gaigher

Scanning electron microscopy of fish scales has facilitated the application of micro-structures to systematics. Electron microscopy studies have added more information on the structure of the scale and the associated cells, many problems still remain unsolved, because of our incomplete knowledge of the process of calcification. One of the main purposes of these studies has been to study the histology, histochemistry, and ultrastructure of both calcified and decalcified scales, and associated cells, and to obtain more information on the mechanism of calcification in the scales. The study of a calcified scale with the electron microscope is complicated by the difficulty in sectioning this material because of the close association of very hard tissue with very soft tissues. Sections often shatter and blemishes are difficult to avoid. Therefore the aim of this study is firstly to develop techniques for the preparation of cross sections of fish scales for scanning electron microscopy and secondly the application of these techniques for the determination of the structures and calcification of fish scales.


Biology ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 51
Author(s):  
Michela Relucenti ◽  
Giuseppe Familiari ◽  
Orlando Donfrancesco ◽  
Maurizio Taurino ◽  
Xiaobo Li ◽  
...  

Several imaging methodologies have been used in biofilm studies, contributing to deepening the knowledge on their structure. This review illustrates the most widely used microscopy techniques in biofilm investigations, focusing on traditional and innovative scanning electron microscopy techniques such as scanning electron microscopy (SEM), variable pressure SEM (VP-SEM), environmental SEM (ESEM), and the more recent ambiental SEM (ASEM), ending with the cutting edge Cryo-SEM and focused ion beam SEM (FIB SEM), highlighting the pros and cons of several methods with particular emphasis on conventional SEM and VP-SEM. As each technique has its own advantages and disadvantages, the choice of the most appropriate method must be done carefully, based on the specific aim of the study. The evaluation of the drug effects on biofilm requires imaging methods that show the most detailed ultrastructural features of the biofilm. In this kind of research, the use of scanning electron microscopy with customized protocols such as osmium tetroxide (OsO4), ruthenium red (RR), tannic acid (TA) staining, and ionic liquid (IL) treatment is unrivalled for its image quality, magnification, resolution, minimal sample loss, and actual sample structure preservation. The combined use of innovative SEM protocols and 3-D image analysis software will allow for quantitative data from SEM images to be extracted; in this way, data from images of samples that have undergone different antibiofilm treatments can be compared.


Author(s):  
Debbie G. Jones ◽  
Albert P. Pisano

A novel fabrication process is presented to create ultra thick ferromagnetic structures in silicon. The structures are fabricated by electroforming NiFe into silicon templates patterned with deep reactive ion etching (DRIE). Thin films are deposited into photoresist molds for characterization of an electroplating cell. Results show that electroplated films with a saturation magnetization above 1.6 tesla and compositions of approximately 50/50 NiFe can be obtained through agitation of the electrolyte. Scanning electron microscopy (SEM) images show that NiFe structures embedded in a 500 μm thick silicon wafer are realized and the roughening of the mold sidewalls during the DRIE aids in adhesion of the NiFe to the silicon.


2021 ◽  
Vol 21 (7) ◽  
pp. 3773-3778
Author(s):  
Keon-Young Kim ◽  
Se-Min Jeong ◽  
Chang-Yull Lee

This paper proposes a new mechanism for detecting microscopic damage of structures based on imitating the sensory organs of spiders. Therefore, it is essential to manufacture sensors that can react sensitively to the micro deformations of structures. Numerous cracks were intentionally generated to improve the sensitivity of the proposed sensor, and an increase in the gap of the crack was observed by scanning electron microscopy (SEM) observation. Electrohydrodynamic technology is used to detect deformations in a structure of depositing Ag nano paste on a polyethylene terephtha-late (PET) substrate. Ag nano lines are also observed by SEM images. The sensor is constructed as a grid structure, by forming layers patterned horizontally and vertically. An impact tester is used to verify the mechanism for structural health monitoring using the developed sensor. The resistance changes of the sensors are applied to estimate the structure’s damaged location. The intersections of the lines with varying resistance can be used to accurately detect crack initiation. The proposed mechanism is a powerful methodology for estimating and detecting microscopic deformations and damage to structures.


2020 ◽  
Vol 861 ◽  
pp. 378-382
Author(s):  
Sophoan Phal ◽  
Muhammad Rafiullah Khan ◽  
Pattarin Leelaphiwat ◽  
Vanee Chonhenchob

Sodium alginate based films containing turmeric oil (TEO) at different concentrations (1, 2 and 3%) were developed. The film with no TEO was used as control. Incorporation of TEO had the effects on the film properties. With increasing TEO concentrations, thickness, elongation at break, permeability of oxygen and water vapor of the films significantly (p ≤ 0.05) increased. Whereas moisture content, tensile strength and modulus of elasticity significantly (p ≤ 0.05) decreased. Scanning electron microscopy (SEM) analysis showed more numerous pores and rougher surface of the antifungal films than the control film.


2020 ◽  
Vol 34 (24) ◽  
pp. 2050249
Author(s):  
L. Yoosefi ◽  
V. Setoodeh

High sensitivity and response ratio of magnetoimpedance (MI) sensors have raised interest for using them in different environments for detection of weak magnetic fields of magnetic elements even though the high dependence of the MI response to the surface condition of the MI sensor has limited its application in some environments. In this study, we investigate the effects originating from the MI measurement in moisturized air. Using scanning electron microscopy (SEM) images, it is observed that the surface of an Fe-based MI sensor has become rough and granular after the presence of moisture on its surface. Results can be useful for developing MI sensors for use in different environmental conditions.


1979 ◽  
Vol 16 (8) ◽  
pp. 1621-1628 ◽  
Author(s):  
Donald E. Champagne ◽  
C. R. Harington ◽  
Don E. McAllister

A nodule containing the cranium of a deepwater sculpin, Myoxocephalus thompsoni (Girard), was discovered in Pleistocene Champlain Sea deposits at Green Creek, 10 km east of Ottawa, Ontario, Canada, and represents the first fossil reported for the species. It provides an additional basis for refuting derivation of the species from a post-Wisconsin marine submergence and suggests an origin at the beginning of the Wisconsin or earlier. Habitat preferences of the species favour an oligotrophic lacustrine environment with bottom summer temperatures below 8 °C in the Champlain Sea or nearby lake basin. The head length of the fossil is 28 mm, the estimated standard length 86 mm. Use of a longwave ultraviolet lamp with the fossil improved contrast between the bones and the clay matrix in photographs. Scanning electron microscopy (SEM) analysis of bone in the fossil failed to detect the presence of strontium.


Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1779 ◽  
Author(s):  
Christoph Naber ◽  
Florian Kleiner ◽  
Franz Becker ◽  
Long Nguyen-Tuan ◽  
Christiane Rößler ◽  
...  

A new method for the nuclear magnetic resonance (NMR) surface relaxivity calibration in hydrated cement samples is proposed. This method relies on a combined analysis of 28-d hydrated tricalcium silicate samples by scanning electron microscopy (SEM) image analysis and 1H-time-domain (TD)-NMR relaxometry. Pore surface and volume data for interhydrate pores are obtained from high resolution SEM images on surfaces obtained by argon broad ion beam sectioning. These data are combined with T2 relaxation times from 1H-TD-NMR to calculate the systems surface relaxivity according to the fast exchange model of relaxation. This new method is compared to an alternative method that employs sequential drying to calibrate the systems surface relaxivity.


Sign in / Sign up

Export Citation Format

Share Document