Structure and Composition of Rhinoceros Horn

1992 ◽  
Vol 292 ◽  
Author(s):  
Ann Chidester Van Orden ◽  
Joseph C. Daniel

AbstractRhinoceros horn has been used medicinally and as a talisman in many cultures and animals are slaughtered to obtain the horn. With the dwindling populations of rhinos, and the limited number and breeding success of captive rhinos, there is a critical need to learn as much as is possible about their horns to find an adequate substitute. Examination of rhino horn was made using optical microscopy, scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), and x-ray diffraction (XRD). The structure of the horn is unusual and consists of two separate phases, one of hair-like filaments, built around a central core in circumferential layers and the other surrounding and filling in the spaces between the filaments as a matrix. Together, these two structures make up a biological composite, structurally similar to metal, ceramic or polymer based composites. The structural morphology, the dimensions of the structures, and the chemistry of the horn are discussed. Comparisons are made between horn, hoof, and hair of rhinos and hoof and hair from horses, their nearest living relatives.

2016 ◽  
Vol 881 ◽  
pp. 422-426
Author(s):  
Carlos Maurício Fontes Vieira ◽  
Regina Maria Pinheiro ◽  
Sergio Neves Monteiro

This work has for objective to evaluate the microstructure of clayey ceramic incorporated with a waste in the form of sludge generated during treatment of effluent of a paper making industry. The microstructure of ceramics incorporated with 0 and 10 wt.% of waste, and then fired at 600°C, was evaluated by optical microscopy, scanning electron microscopy and X-ray diffraction. The results showed that the waste changes the microstructure of the clayey ceramic increasing the porosity, as well as forming new crystalline phases, mainly with calcium compounds.


Author(s):  
Mohammad K. Hossain ◽  
Samira N. Shaily ◽  
Hadiya J. Harrigan ◽  
Terrie Mickens

A completely biodegradable composite was fabricated from an herbal polymer, soy protein concentrate (SPC) resin. Soy protein was modified by adding 30 wt% of glycerol and 5 wt% of poly vinyl alcohol (PVA) to enhance its mechanical as well as thermal property. 3%, 5%, 10%, and 20% nanoclay (NC) were infused into the system. To evaluate its mechanical properties, crystallinity, thermal properties, bonding interaction, and morphological evaluation, tensile, X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR) tests, and optical microscopy (OM) and scanning electron microscopy (SEM) evaluation were performed. Tensile tests showed that the addition of nanoclay improved the mechanical properties of the modified resin. Soy protein is hydrophilic due to the presence of amino acids that contain various polar groups such as amine, carboxyl, and hydroxyl. As a result, polar nanoclay particles that are exfoliated can be evenly dispersed in the SPC resin. From experimental results, it is clear that adding of nanoclay with SPC resin significantly increased the stiffness of the SPC resin. A combination of 5% clay, 30% glycerol, and 5% PVA with the modified SPC resulted in the maximum stress of 18 MPa and Young modulus of 958 MPa. The modified SPC showed a reduced failure strain as well. X-ray diffraction curves showed an improvement of crystallinity of the prepared resin with increasing amount of nanoclay. Interaction among soy, glycerol, PVA, and nanoclay was clearly demonstrated from the FTIR analysis. Optical microscopy (OM) and scanning electron microscopy (SEM) micrographs revealed rougher surface in the nanoclay infused SPC samples compared to that of the neat one. SEM evaluation revealed rougher fracture surface in the NC infused samples.


2015 ◽  
Vol 817 ◽  
pp. 593-598
Author(s):  
Yan Feng Liang ◽  
Sheng Quan Dong ◽  
Gao Hong Li

In situ TiCp/Al-4.5wt.%Cu composites have been coated using an electro-less Ni-P plating technique. The morphology and composition of the plating coating have been examined by scanning electron microscopy, optical microscopy, and X-ray diffraction. The results indicated that the coating had a high-phosphorus amorphous microstructure. The coatings microstructures showed significantly changes when the citric acid concentration in the chemical bath was varied in the range 16-20g/L.


Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5235
Author(s):  
Yang Liu ◽  
Ying-Xin Wang ◽  
Qiang Yang ◽  
Fu Wang

A two-stepped coating-sintering process to prepare the qualified Ni–Ti transition applied in metal-ceramic bonding proved to be effective to improve the wetting abilities. The method was introduced in detail and compared with 2 control groups. To analyze the benefits, the morphology and composition were captured by field emission scanning electron microscopy (FE-SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The comparisons of different coating depths and different sintering conditions were also recorded and analyzed. The influence of the EDS detecting depth was a concern in the discussions. Finally, the contact angle tests and surface energies were also estimated to verify the reliability of the transition layer. The results indicated that the coating-sintering process combined with protective sintering was preferred and necessary to increase the activeness.


2021 ◽  
Vol 8 (2021) (2) ◽  
pp. 1-41
Author(s):  
Marcus Brito ◽  
◽  
Marcondes Costa ◽  
Herbert Pöllmann ◽  
Mário Chaves ◽  
...  

The diamonds from the Painin garimpo, on the Tapajós River, in Itaituba, state of Pará, were mined in alluvial gravel in geological terrains dominated by the Barreirinha, Itaituba and Monte Alegre Paleozoic formations. 30 diamonds extracted from the concentrates of this garimpo were analyzed by stereomicroscopy, optical microscopy, x-ray diffraction, scanning electron microscopy with EDS and luminescence. The average weight of these specimens is 0.42 ct and the predominant forms are dodecahedral and octahedral, in addition to others such as ballas and bort. Surface figures, microstructures, luminescence, and various inclusions are recognized. The inclusions can be classified as syngenetic (periclase, diopside, among others) and epigenetic (eg minerals of crandallite group). Green covers were also observed. This study, however, was not able to solve the problem of the genesis of the diamond in the studied region, as happens to date with most secondary diamond deposits in the Amazon region (Tapajós, Tocantins and Tepequém-Maú), except for those related to kimberlite pipes of Mato Grosso Rondônia.


1983 ◽  
Vol 26 ◽  
Author(s):  
D. P. Stinton ◽  
E. W. Mcdaniel ◽  
H. O. Weerent

ABSTRACTPhases present in injected grouts were characterized by use of optical microscopy, scanning electron microscopy, x-ray diffraction, and β-γ autoradiography. A laboratoryproduced sample containing 1 wt % stable cesium and an actual grout sheet obtained by core drilling were examined. The phases present in these samples were identified, and cesium was found to be absorbed almost entirely by illite clay agglomerates. These clay agglomerates were tightly bound within the grout structure by hydrated calcium silicates. The β-γ autoradiography of the core-drilled sample verified that cesium and other radionuclides were trapped within the 20-year-old grout and had not migrated into trapped shale fragments.


Cerâmica ◽  
2015 ◽  
Vol 61 (360) ◽  
pp. 409-413 ◽  
Author(s):  
S. H. da Silva Filho ◽  
L. Bieseki ◽  
A. R. da Silva ◽  
A. A. B. Maia ◽  
R. A. S. San Gil ◽  
...  

Abstract The synthesis of zeolite A employing kaolin waste from paper coating was studied. The kaolin waste was pre-treated at 550 to 800 ºC. For comparison purposes, a sample of zeolite A was also prepared using the IZA procedure. The materials were characterized by 27Al MAS NMR, X-ray diffraction and scanning electron microscopy using a microprobe. Pretreatment was necessary, and the best temperatures were between 600 and 700 ºC. The zeolite A formation was observed in all the prepared materials, reaching 52% crystallinity. On the other hand, the sodalite phase and amorphous materials were also formed.


2011 ◽  
Vol 361-363 ◽  
pp. 2012-2015
Author(s):  
Chang Yun Chen ◽  
Feng Zhou ◽  
Chun Hua ◽  
Zhao Hui Li ◽  
Huan Pang

A facile hydrothermal method without any templates has been developed for the preparation of α- Fe2O3nanocubes and hollow spheres. The as-synthesized products is then characterized using X-ray diffraction(XRD), scanning electron microscopy(SEM). The nanocubes have extraordinary unity and we can anticipate its unique magnetic characteristic. On the other hand, the hollow sphere structure has a promising future in the application as carriers for targeting drug delivery. In our opinions, the method is not only very simple, but also is very friendly to the environment.


2021 ◽  
Vol 21 (3) ◽  
pp. 789-806
Author(s):  
MONA F. ALI ◽  
HALA A. M. AFIFI ◽  
AML M. LOTFY

The stucco window in this study is kept in the stores of the Museum of Islamic Art in Cairo, Egypt, and bears the number 454/7. This window has been exposed to many damage factors, the most important of which is the fire that broke out in the museum in 2006 AD, in addition to the effect of the water that was used to extinguish the fire. This research aims to study the components of the window (stucco - glass - wood) and identify the transformations resulting from the effect of fire using optical microscopy, scanning electron microscopy coupled with EDX, X-ray diffraction, and infrared spectroscopy. In addition, the microbiological damage resulting from the moisture that saturates the plaster and wood was investigated.


Author(s):  
A.J. Stavros

Abstract Two different W-Co-C powders were used in three deposition devices, the Super D-Gun, Jet Kote, and JP-5000 to produce coatings for laboratory immersion tests in molten zinc and %55Al-Zn. Resistance was evaluated as time to failure. Scanning electron microscopy and X-ray diffraction were used to characterize the structures ssid failure mechanism. All coatings were found to fail when the molten metal breached the coating thickness at weak spots and spread out over the underlying interface to lift the coating away from the underlying 316L substrate. These weak spots were "pits" on one Super D-Gun coating (the most resistant coating) and cracks on all the other coatings. No diffusion of zinc through the tungsten carbide coatings was observed.


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