On the Relationship between Inclusions and Pores, Part II: Dendritic Structure, Pressure Drop in the Liquid and Pore Precipitation

2014 ◽  
Vol 790-791 ◽  
pp. 302-307 ◽  
Author(s):  
Arash Safavi Nick ◽  
Hasse Fredriksson
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Pore Formation ◽  
Pressure Field ◽  
Primary Dendrite ◽  
Dendritic Structure ◽  
Steel Sample ◽  
Continuously Cast ◽  
The Relationship ◽  
Scanning Electron

There is a relationship between pores and inclusions. As hypothesis goes, inclusions have an affinity to gather inside the pores and form clusters. Focus of this paper is how solidified dendritic structure affects the pressure field in the liquid and pore precipitation in austenitic stainless steel. Steel sample is a continuously cast bloom. Temperature profile and width of the mushy zone of the strand is modeled according to a constant temperature at the strands surface. Thermal analysis has been performed with differential thermal analysis (DTA) and differential scanning calorimeter (DSC). Dendrite arm spacing (DAS) is measured with light optical microscopy (LOM) and scanning electron microscopy (SEM). DAS is represented as the weight average of the distance between parallel sets of primary dendrite stems. Pressure field is calculated based on Darcys law. Pore formation is described through segregation of the gas components and pressure field in the liquid.

Microstructural Evolution of Mg-4Al-2.5Ca Alloy during Solidification

2015 ◽  
Vol 816 ◽  
pp. 486-491 ◽  
Author(s):  
Zhong Tao Jiang ◽  
Bin Jiang ◽  
Jian Yue Zhang ◽  
Xiang Sheng Xia ◽  
Fu Sheng Pan
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Energy Dispersive Spectrometer ◽  
Dendritic Structure ◽  
Eutectic Phase ◽  
Scanning Calorimetry ◽  
Phase Separation Temperature ◽  
Separation Temperature ◽  
Scanning Electron ◽  
Cast Microstructure

In the present work, the microstructure evolution of Mg-4Al-2.5Ca alloy during solidification was investigated by means of scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and differential scanning calorimetry (DSC). The results showed that the as-cast microstructure was typical dendritic structure, consisting of α-Mg and the Al2Ca with a C15 structure formed at inter-dendritic regions. But during slow solidification, the sequence of phase formation of this alloy consisted of following stages: L→ L + α-Mg → L + α-Mg + (Mg, Al)2Ca → α-Mg + (Mg, Al)2Ca + Al2Ca → α-Mg + Al2Ca. Thermal analysis showed that the (Mg, Al)2Ca and Al2Ca phase separation temperature was about 520°C and 510°C respectively, which is different from thermodynamic calculation. With the temperature decreasing, the liquid (Mg, Al)2Ca phase with thick and continuous morphology transformed into lamellar-shaped eutectic phase, and parts of (Mg, Al)2Ca phase translated into Al2Ca phase with bone-shaped and needle-like.

PENINGKATAN LAJU DISOLUSI ACYCLOVIR DENGAN METODE SISTEM DISPERSI PADAT MENGGUNAKAN POLOXAMER 188

2016 ◽  
Vol 5 (1) ◽  
pp. 6
Author(s):  
Budi Setiawan ◽  
Erizal Zaini ◽  
Salman Umar
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Scanning Electron Microscopy ◽  
Fourier Transform ◽  
Differential Thermal Analysis ◽  
Fourier Transform Infrared ◽  
X Ray Diffraction ◽  
Poloxamer 188 ◽  
X Ray ◽  
Scanning Electron

Sebuah penelitian tentang sistem dispersi padat dari asiklovir dengan poloxamer 188 telah dilakukan formulasi dengan pencampuran secara fisika dengan rasio 1 : 1, 1 : 3, 1 : 5 dan dispersi padat 1 : 1, 1 : 3, 1 : 5 dan penggilingan 1:1 sebagai pembanding. Dispersi padat dibuat menggunakan metode pencairan (fusi), yang digabung dengan poloxamer 188 pada hotplate kemudian asiklovir dimasukkan ke dalam hasil poloxamer 188 lalu di kocok hingga membentuk masa homogen. Semua formula yang terbentuk termasuk asiklovir poloxamer 188 murni dianalisis karakterisasinya dengan Differential Thermal Analysis (DTA), X-ray Diffraction, Scanning Electron Microscopy (SEM), dan Fourier Transform Infrared (FTIR), kemudian pengambilan dilakukan  (penentuan kadar) mengunakan spektrofotometer UV pada panjang gelombang 257,08 nm dan uji laju disolusi dengan aquadest bebas CO2 menggunakan metode dayung. Hasil pengambilan  (penentuan kadar) menunjukkan bahwa semua formula memenuhi persyaratan farmakope Amerika edisi 30 dan farmakope Indonesia edisi 4 yaitu 95-110%. Sedangkan hasil uji laju disolusi untuk campuran fisik 1: 1, dan dispersi padat 1: 1, dan penggilingan 1: 1 menunjukkan peningkatan yang nyata dibandingkan asiklovir murni. Hal ini juga dapat dilihat dari hasil perhitungan statistik  menggunakan analisis varian satu arah  SPSS 17.

scholarly journals Three-dimensional relationships between tumor cells and microcirculation with double cyanine immunolabeling, laser scanning confocal microscopy, and computer-assisted reconstruction: an alternative to cast corrosion preparations.

1994 ◽  
Vol 42 (5) ◽  
pp. 681-686 ◽  
Author(s):  
V Rummelt ◽  
L M Gardner ◽  
R Folberg ◽  
S Beck ◽  
B Knosp ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Blood Vessels ◽  
Tumor Cells ◽  
Laser Scanning ◽  
Three Dimensional ◽  
Melanoma Cells ◽  
Tumor Blood Vessels ◽  
The Relationship ◽  
Scanning Electron

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.

scholarly journals Some aspects of nickel electrodeposition in the presence of a magnetic field

2005 ◽  
Vol 70 (10) ◽  
pp. 1213-1217 ◽  
Author(s):  
Nebojsa Nikolic
Keyword(s):  
Magnetic Field ◽  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Magnetic Properties ◽  
Dendritic Structure ◽  
Nickel Deposit ◽  
Nickel Electrodeposition ◽  
Nickel Deposits ◽  
Scanning Electron

Nickel deposits obtained from a Watt solution both without and with a perpendicularly oriented magnetic field were examined by scanning electron microscopy (SEM). The nickel deposit obtained without an imposed magnetic field was very rough, with a clearly visible clustered structure. The nickel deposit obtained under a perpendicularly oriented magnetic field has a very developed dendritic structure, which can be denoted as arboreous ? bead dendritic structure. The ob- served difference is essentially ascribed to the effect of a magnetic field on the magnetic properties of nickel.

Casting Recycling of Animal Protein-Based Binder Sand

2012 ◽  
Vol 573-574 ◽  
pp. 1156-1160
Author(s):  
Hong Yu Shi ◽  
Hui Liu ◽  
Shu Lan Guo
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Scanning Electron Microscopy ◽  
Protein Binding ◽  
Animal Protein ◽  
Experimental Result ◽  
Environmental Friendly ◽  
Traditional Technologies ◽  
Scanning Electron

This study is focusing on the protein sand binder on the performance of wet sand, and explores the protein binding mold sand reusability and reclamation. With thermal analysis and scanning electron microscopy testing, and by comparing with other traditional technologies, the experimental result shows that it is a more environmental friendly.

Four new species of monoraphid diatoms from Western Sichuan Plateau in China

Phytotaxa ◽  
2021 ◽  
Vol 479 (3) ◽  
pp. 257-274
Author(s):  
Q.M. YOU ◽  
K. ZHAO ◽  
Y.L. WANG ◽  
P. YU ◽  
J.P. KOCIOLEK ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
New Species ◽  
Central Area ◽  
Morphological Characteristics ◽  
Similar Species ◽  
Small Species ◽  
Western Sichuan ◽  
The Relationship ◽  
Scanning Electron ◽  
Apical Axis

Four new monoraphid diatoms are examined and described from a high-altitude (> 3000 m) region of western Sichuan, China.  The descriptions are based on light and scanning electron microscopy observations, and the four new species are compared with similar taxa worldwide.  Achnanthidium sichuanense sp. nov. has small, lanceolate-elliptical valves, with rounded apices. The outline and central area differentiate it from similar species.  The unique characteristic of Eucocconeis undulatum sp. nov. is that it has valves that are undulate along the apical axis, forming an “H”-shaped area on both raphe and rapheless valves as seen in light microscope (LM).  Platessa mugecuonesis sp. nov. and Platessa lanceolata sp. nov. are two small species, whose valve outlines and central areas make them different from other species in this genus.  A. sichuanense sp. nov. and E. undulatum sp. nov. are discussed in terms of the relationship between “Achnanthidium & Psammothidium” and “Eucocconeis & Psammothidium”, as these genera are difficult to separate according to morphological characteristics.

Elimination of Acid Red 88 by Waste Product from the Phosphate Industry: Batch Design and Regeneration

2021 ◽  
Author(s):  
Khaled Boughzala ◽  
Mustapha Hidouri
Keyword(s):  
Electron Microscopy ◽  
Experimental Data ◽  
Thermal Analysis ◽  
Waste Product ◽  
Langmuir Model ◽  
X Ray Diffraction ◽  
Retention Capacity ◽  
Phosphate Industry ◽  
Pseudo Second Order ◽  
Scanning Electron

Waste regenerated after washing of rock phosphate and phosphogypsum has been proposed as removal agents of Acid Red 88 (AR 88)) from artificially contaminated solution. Natural phosphate (PN) was also studied for comparison. These materials were characterized beforehand, as is intended for the removal tests, by chemical analysis, powder X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetric analysis– differential thermal analysis, scanning electron microscopy, and N2 adsorption isotherms. The conducted experiments show that among the different materials, the PWR has the highest retention capacity of the dye (123.4 mg g−1) of AR-88. Upon calcinations, the removal capacities reduced by 60 to 70%. We take note also that a decrease in the amount of removed AR 88 dye occurs with an increase in pH. The kinetics data on the reaction between AR 88 and the materials are described well by a pseudo -second-order model. The Langmuir model is successfully applied to the experimental data of the removal of acid red 88. The removal process is exothermic.

Effect of Heat Treatments on Wettability of Nacre

2020 ◽  
Vol 985 ◽  
pp. 86-90
Author(s):  
Andi Muhammad Anshar ◽  
Sengo Kobayashi ◽  
Satoshi Okano
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Scanning Electron Microscopy ◽  
Heating Temperature ◽  
Pearl Oyster ◽  
Heat Treatments ◽  
Organic Substances ◽  
Water Contact ◽  
X Ray ◽  
Scanning Electron

The surface wettability of biomaterials influences on osteoblast behavior and bone formation. In this research, the variation of wettability of nacre by heat treatments was examined. Plates of the nacre were fabricated from shells of the Akoya pearl oyster. The specimens were heated at 100, 200, 300, 400, 500, and 600 °C. Characterizations of the specimens during and after heat treatments were carried out using scanning electron microscopy, X-ray diffractometry, and thermogravimetry-differential thermal analysis. The water contact angle (WCA) of the specimen was measured to evaluate wettability. The color of nacre changed from iridescent color to brownish weak-iridescence by the heating at and over 300 °C. The nacre heated at and over 300 °C became brittle because organic substances in nacre, which acts as the glue between the aragonite platelets were evaporated by the heating. The WCA of the specimen was decreased with increasing heating temperature, which should be related to the decrease in the number of organic substances in nacre by the heating.

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