scholarly journals The Analysis on the Relationship between Dating and the Gel-ink Material Penetration of Handwriting along Z Direction on Paper

CONVERTER ◽  
2021 ◽  
pp. 363-369
Author(s):  
Jiangchun Li, Et al.

Scanning electron microscopy (SEM) technology has been widely used in forensic science, which promotes the development of interdisciplinary science. This paper used SEM to observe the penetration degree of common black gel-ink on paper. The penetration morphology of the different black brands gel-ink has been observed. The relationship between the penetration process of gel-ink material and the dating of document has been observed after determining the measuring position. The results showed that the penetration depth of ink along Z direction on paper is significantly different, the penetration speed of ink is also different, which presents regular variety and gradually reaches a relatively stable state over time. The application of SEM will provide a useful exploration for judging the ink dating.

1994 ◽  
Vol 42 (5) ◽  
pp. 681-686 ◽  
Author(s):  
V Rummelt ◽  
L M Gardner ◽  
R Folberg ◽  
S Beck ◽  
B Knosp ◽  
...  

The morphology of the microcirculation of uveal melanomas is a reliable market of tumor progression. Scanning electron microscopy of cast corrosion preparations can generate three-dimensional views of these vascular patterns, but this technique sacrifices the tumor parenchyma. Formalin-fixed wet tissue sections 100-150 microns thick from uveal melanomas were stained with the lectin Ulex europaeus agglutinin I (UEAI) and proliferating cell nuclear antigen (PCNA) to demonstrate simultaneously the tumor blood vessels and proliferating tumor cells. Indocarbocyanine (Cy3) was used as a fluorophore for UEAI and indodicarbocyanine (Cy5) was used for PCNA. Double labeled sections were examined with a laser scanning confocal microscope. Images of both stains were digitized at the same 5-microns intervals and each of the two images per interval was combined digitally to form one image. These combined images were visualized through voxel processing to study the relationship between melanoma cells expressing PCNA and various microcirculatory patterns. This technique produces images comparable to scanning electron microscopy of cast corrosion preparations while permitting simultaneous localization of melanoma cells expressing PCNA. The microcirculatory tree can be viewed from any perspective and the relationship between tumor cells and the tumor blood vessels can be studied concurrently in three dimensions. This technique is an alternative to cast corrosion preparations.


2019 ◽  
Vol 38 (3) ◽  
pp. 682-702 ◽  
Author(s):  
Zepeng Sun ◽  
Yue Ni ◽  
Yongli Wang ◽  
Zhifu Wei ◽  
Baoxiang Wu ◽  
...  

The chemical and physical capabilities of shale can be altered by the interactions between fracturing fluid and shale formation, affecting the long-term reservoir productivity. To obtain information regarding how fracturing fluids with different components impact the pore structure, porosity and mineral compositions of shale reservoir rocks over time, two different types of commercial fracturing fluids (slick water and crosslinked gel) were used to react with the shales from Longmaxi Formation of Lower Silurian in the Sichuan Basin of South China. Experiments were conducted with various time intervals (1, 4 and 10 days) in a reactor at 50 MPa and 100°C, and then analytical methods including X-ray diffraction, low pressure nitrogen adsorption, field emission scanning electron microscopy and porosity measurement were used to examine the changes of mineralogical compositions, pore structure and porosity. The results demonstrated that the mineral compositions of shale samples were significantly changed after treatment with two different fracturing fluids for 4 days. The analysis of field emission scanning electron microscopy revealed that the carbonate minerals were dissolved and developed many dissolution pores after slick water treatment, while the crosslinked gel mainly caused the precipitation of carbonate minerals. After exposure to different fracturing fluids, the total pore volume and specific surface area decreased over time. Moreover, the fractal dimensions (D1 and D2) of shale showed an apparent decrease trend after treatment with two different fracturing fluids, indicating that the pore surface and structure become smooth and regular. The porosity of shale significantly decreased by 15.9% and 17.8%, respectively, after 10 days of slick water and crosslinked gel treatment. These results indicated that the injection of the two different types of fracturing fluids may negatively impact the shale gas production through reducing the nanopore structure and porosity of shale reservoir rocks.


2014 ◽  
Vol 936 ◽  
pp. 1485-1489 ◽  
Author(s):  
Yue Li ◽  
Huan Tong ◽  
Jin Bo Yang ◽  
Wan Guo Dong

In order to detect the influence of age on the experiment that use scanning electron microscopy (SEM) to determinate the original water-cement ratio (w/c) of hardened concrete, a series of concrete mixes are tested. Experimental results show that early ages do have an effect on the water-cement ratio of hardened concrete that determined from scanning electron microscopy, this effect will decrease while age increases. The relationship between capillary porosity, w/c and age is analyzed and a calculation equation is given.


2006 ◽  
Vol 17 (1) ◽  
pp. 77-89 ◽  
Author(s):  
Douglas H. Ubelaker ◽  
Karen E. Stothert

AbstractThe relationship between Andean coca use and dental deposits is explored through the use of scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Elemental analyses of samples of large dental deposits from archeologically recovered skeletons from Ecuador dating between 500 B.C. and A.D. 1532 are compared with those of normal calculus deposits of individuals from North America (modern and precontact), of normal tooth structure and of samples of alkali recovered from Ecuadorian artifacts thought to have been employed in coca use. Spectral analysis revealed homogeneity among all dental samples (deposits and structure) and that they are distinct from the elemental pattern revealed in the analysis of the artifact alkalis.


Author(s):  
Yafeng He ◽  
Wenzhuang Lu ◽  
Weiming Gan ◽  
Jianshe Zhao ◽  
Dunwen Zuo

Electrochemical machining is a promising method for titanium alloy processing. The polarization characteristics of Ti6Al4V were studied in detail in order to provide a deeper understanding of this method. The polarization curve of the alloy, which shows the relationship between current density and potential under an external electric field, was obtained in NaBr electrolyte at three different concentrations in a three-electrode electrochemical test system. The surface topography of the polarization zone and pits was examined by scanning electron microscopy, and their fractal features were calculated by the picture point cover method. The results show that Ti6Al4V in the more concentrated electrolyte has higher dissolution rate, lower decomposition potential, and more uniform surface topology in the polarization areas.


2014 ◽  
Vol 614 ◽  
pp. 140-143 ◽  
Author(s):  
Florin Miculescu ◽  
Lucian Toma Ciocan ◽  
Daniela Meghea ◽  
Marian Miculescu

Sintered ceramics and ceramic glasses are frequently used as biomaterials for dental restorations, usually for inlays, onlays, veneers, crowns or bridges. In this study we analyzed several types of ceramic-ceramic type prosthetic restorations in order to assess the types of defects that can lead to their failure. The research aim is to morphologically identify by scanning electron microscopy the main types of defects that lead to failure over time of ceramic-ceramic prostheses type. The type of failure registered were fracture of plating material (feldspatic porcelain) and fracture of entire structure (zirconia and feldspatic porcelain).


2011 ◽  
Vol 85 (4) ◽  
pp. 453-457 ◽  
Author(s):  
A.M. McCarthy

AbstractThe surface topography of 15-day-old adult Echinoparyphium recurvatum (Von Linstow, 1873) sensu stricto, from an isolate of the parasite utilizing Lymnaea peregra as first intermediate host in southern England, is described and illustrated using scanning electron microscopy, and is compared to those of other Echinoparyphium species from Europe, and with those of E. recurvatum of East Asian origin. The general morphology of tegumental features was found to be very similar to that of worms of the same age observed in a previous study on a Korean isolate of E. recurvatum. Comparison of collar and body spination of E. recurvatum with other 45-collar-spined members of the genus in Europe revealed some significant differences in morphology. Collar spines of E. recurvatum were found to be shorter and more pointed than those of Echinoparyphium mordwilkoi. The body spines of E. recurvatum are rounded and scale-like, extending just beyond the ventral sucker, contrasting with the pointed, thorn-shaped body spines of E. mordwilkoi, extending posteriorly to the level of the second testis. Body spine shape and distribution in E. recurvatum were found to be more similar to those of Echinoparyphium pseudorecurvatum. The value of SEM studies in elucidating the relationship between members of the genus Echinoparyphium in Britain/Europe and those in Africa, Asia and North America is suggested.


Respuestas ◽  
2021 ◽  
Vol 25 (2) ◽  
pp. 117-124
Author(s):  
Henry Mauricio-Mateus ◽  
José Barba-Ortega ◽  
Miryam Rincón-Joya

In this work, we studied the change in the electric current and the length of the nanotubes depending on the area and the exposure time in the anodizing process. Over time the anodizing area was changed with a rate of 0.5 cm2 to 2.5 cm2 using a total anodizing time of 60 min, using a chemical solution (2ml  /3 ml /0.30g ) and maintaining a constant anodizing voltage equal to 20 V. The behavior in the nanostructures was recorded by the evolution of the current density as a function of the anodizing time. The morphology of the nanostructures was analyzed by means of scanning electron microscopy (SEM). With the use of the Imagej program. The size, length and diameter of the titanium nanostructures are obtained. The sample that presented the best behavior was that of an anodizing area of ​​1.5 cm2  and an anodizing time of 36 min. This presents a surface where open nanotubes are observed in the upper part with a vertical length of 0.23 μm and a pattern thereof organized in a circular arrangement with a diameter of 0.035 μm. It was observed that increasing the area under these anodizing conditions decreased the length of the nanotubes. The mobility of the loads was always greater with the area of ​​exposure, which is observed in the increase of the current


Caryologia ◽  
2021 ◽  
Vol 74 (3) ◽  
pp. 31-43
Author(s):  
Jun Wang ◽  
Qiang Ye ◽  
Tong Zhang ◽  
Xusheng Shi ◽  
Majid Khayatnezhad ◽  
...  

Pollen morphology of 23 species belonging to Geranium have been studied in details, which represent eight sections of two subgenera i.e., G. sect. Dissecta, Geranium, and Tuberosa of subgen. Geranium, Divaricata, Lucida, Ruberta and Trilopha of subgen. Robertium. These plant species were collected from different phytogeographical regions of Iran. The palynological investigation was done using scanning electron microscopy (SEM) techniques. Different palyno-morphological features have been observed, and the closely related species were distinguished. We used different multivariate statistical methods to reveal the species relationships. Ward clustering analyses have been done to check out the relationship among the species. The shapes of pollen grains were monad, radially symmetric, isopolar, apertures were tricolporate, and of spheroid, prolate-spheroid or sub-prolate classes. Three pollen types were recognized on the basis of differences in exine sculpturing pattern: reticulate-clavate, striate-rugulate, reticulum cristatum with clavae. Observed differences were not of diagnostic importance in subgenera and sections level. The main objective of this study is to find distinguish pollen characters in the species of the genus Geranium and to elucidate their systematics importance.


1978 ◽  
Vol 56 (4) ◽  
pp. 519-525 ◽  
Author(s):  
J. H. Borden ◽  
A. Rose ◽  
R. J. Chorney

Elongate placoid sensilla were present on all 20 flagellar segments in five male Aphidius smithi and all but the basal 1 of 17 segments in five females. They are oriented longitudinally, approximately equidistant around the circumference of a segment. Scanning electron microscopy of the internal cuticular surface disclosed lamellae which divide the sensillum into lateral and median channels. Many transverse ridges are present in the ceiling of the median channel. Unlike other species, there is no cuticular floor of the sensillum. Numerous nerve cell bodies in the subcuticular tissue give rise to dendritic processes, a ciliary region, and a region of dendritic branches which lie parallel to each other within the 1-μm-wide median channel underneath the 0.1- to 0.25-μm-thick dome. Each dendritic branch is composed of a neurotubule surrounded by a plasma membrane. The ascending dendrites are flanked by the microvilli of the trichogen cell. A tormogen cell encloses the trichogen cell and extends into the lateral channels of the sensillum. The relationship of minute pores in the dome with the underlying dendritic branches is unclear. The hypothesis is advanced that the sensilla may be involved in host finding through perception of infrared radiation.


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