Confirmation of the surface structures of goethite (α-FeOOH) and phosphated goethite by infrared spectroscopy

1976 ◽  
Vol 72 (0) ◽  
pp. 1082 ◽  
Author(s):  
Roger L. Parfitt ◽  
James D. Russell ◽  
Victor C. Farmer
Keyword(s):  
Infrared Spectroscopy ◽  
Surface Structures

scholarly journals Insight into the Interaction between Water and Ion-Exchanged Aluminosilicate Glass by Nanoindentation

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2959
Author(s):  
Xiaoyu Li ◽  
Liangbao Jiang ◽  
Jiaxi Liu ◽  
Minbo Wang ◽  
Jiaming Li ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Infrared Spectroscopy ◽  
Young’S Modulus ◽  
Surface Stress ◽  
Young's Modulus ◽  
Surface Structures ◽  
Aluminosilicate Glass ◽  
Hydration Time ◽  
Stress Layer ◽  
Insight Into

This work aims to explore the interaction between water and ion-exchanged aluminosilicate glass. The surface mechanical properties of ion-exchanged glasses after different hydration durations are investigated. The compressive stress and depth of stress layer are determined with a surface stress meter on the basis of photo-elasticity theory. The hardness and Young’s modulus are tested through nanoindentation. Infrared spectroscopy is used to determine the variation in surface structures of the glass samples. The results show that hydration has obvious effects on the hardness and Young’s modulus of the raw and ion-exchanged glasses. The hardness and Young’s modulus decrease to different extents after different hydration times, and the Young’s modulus shows some recovery with the prolonging of hydration time. The ion-exchanged glasses are more resistant to hydration. The tin side is more resistant to hydration than the air side. The results are expected to serve as reference for better understanding the hydration process of ion-exchanged glass.

scholarly journals The mineralogy and structure of use-wear polish on chert

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Patrick Schmidt ◽  
Alice Rodriguez ◽  
Kaushik Yanamandra ◽  
Rakesh K. Behera ◽  
Radu Iovita
Keyword(s):  
Infrared Spectroscopy ◽  
Amorphous Film ◽  
Amorphous Layer ◽  
Stone Tools ◽  
Surface Structures ◽  
Physical Processes ◽  
Amorphous Films ◽  
Use Wear ◽  
Competing Hypotheses ◽  
Amorphous Surface

AbstractPolished edges of archaeological stone tools are commonly investigated to obtain information on the tools’ uses in prehistory. Yet to this day, it remains unclear what exactly such polishes are and how they form. Answering these questions should allow the elaboration of new interpretative methods based on objective measurements. Two major competing hypotheses of polish formation have been proposed: abrasion and the formation of a thin amorphous film on the chert or flint surface. We employ reflectance infrared spectroscopy, a technique particularly sensitive to thin amorphous films, to investigate these two hypotheses. We found no added amorphous layer that would have formed upon friction against bone, antler, ivory or wood. Our observations suggest polish formation by abrasion, notwithstanding previous claims of added amorphous surface structures. This has implications for our understanding of the physical processes taking place during friction of chert and flint against different materials. Our results also open the possibility to propose new pathways for identifying different use-wear processes, based on the degree of abrasion.

Surface Structure and Emissivity of Aluminum Nitride Films

2015 ◽  
Vol 1110 ◽  
pp. 163-168 ◽  
Author(s):  
Masashi Yoshida ◽  
Noah Utsumi ◽  
Ryuta Ichiki ◽  
Jung Hyun Kong ◽  
Masahiro Okumiya
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Aluminum Nitride ◽  
Surface Structures ◽  
Gas Nitriding ◽  
Aluminum Substrates ◽  
Scanning Electron ◽  
Total Emissivity

In this study, aluminum nitride films were formed on aluminum substrates by gas nitriding in order to improve their low emissivities. To accomplish this, aluminum alloys were subjected to nitriding conditions at 773 and 823 K for 0–5 h, using alumina and magnesium powders. The resulting aluminum nitride films were several micrometers thick and the films were dark brown or black. The surface structures of the aluminum nitride films were investigated using a scanning electron microscope, which showed fine acicular aluminum nitride nodules with diameters on the order of several micrometers. Emissivities were evaluated at 298 K using Fourier transform infrared spectroscopy, in a wavelength range of 2–14 μm. Total emissivities at temperatures between 323 and 383 K were estimated from emissivity results obtained at 298 K. It was subsequently found that emissivity decreases with increasing wavelength and an emissivity of 0.80 was observed at a wavelength of 2 μm. Total emissivity was 0.49 % at 298 K and was in excess of 0.50 between 323 and 383 K.

Surface Modification of Wool Fabric by Plasma Combined Grafting Treatment

2014 ◽  
Vol 1048 ◽  
pp. 120-124 ◽  
Author(s):  
Xian Cheng Wang ◽  
Lei Zhu ◽  
Qiu Bao Zhou ◽  
Jun Li Chen
Keyword(s):  
Fourier Transform ◽  
Surface Modification ◽  
Infrared Spectroscopy ◽  
Plasma Treatment ◽  
Fourier Transform Infrared Spectroscopy ◽  
Surface Structures ◽  
Wool Fabric ◽  
Grafting Ratio ◽  
Structures And Properties ◽  
Wetting Time

In order to study surface structures and properties of wool fabric, plasma treatment, grafting and plasma combined grafting treatment are studied in this paper. The structure of samples was characterized by Fourier transform infrared spectroscopy (FTIR). Furthermore, wetting time, grafting ratio and whiteness were also investigated.

Scanning and Transmission Microscopy of Nematocyst Batteries in Epitheliomuscular Cells of Hydra

1971 ◽  
Vol 29 ◽  
pp. 410-411 ◽  
Author(s):  
Jane A. Westfall ◽  
S. Yamataka ◽  
Paul D. Enos
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Osmium Tetroxide ◽  
External Surface ◽  
Three Dimensional ◽  
Surface Structures ◽  
Transmission Microscopy ◽  
Transmission Electron ◽  
Freeze Dried ◽  
Scanning Electron

Scanning electron microscopy (SEM) provides three dimensional details of external surface structures and supplements ultrastructural information provided by transmission electron microscopy (TEM). Animals composed of watery jellylike tissues such as hydras and other coelenterates have not been considered suitable for SEM studies because of the difficulty in preserving such organisms in a normal state. This study demonstrates 1) the successful use of SEM on such tissue, and 2) the unique arrangement of batteries of nematocysts within large epitheliomuscular cells on tentacles of Hydra littoralis.Whole specimens of Hydra were prepared for SEM (Figs. 1 and 2) by the fix, freeze-dry, coat technique of Small and Màrszalek. The specimens were fixed in osmium tetroxide and mercuric chloride, freeze-dried in vacuo on a prechilled 1 Kg brass block, and coated with gold-palladium. Tissues for TEM (Figs. 3 and 4) were fixed in glutaraldehyde followed by osmium tetroxide. Scanning micrographs were taken on a Cambridge Stereoscan Mark II A microscope at 10 KV and transmission micrographs were taken on an RCA EMU 3G microscope (Fig. 3) or on a Hitachi HU 11B microscope (Fig. 4).

Electron Microscopic Observation of Biological Specimens in Their Native State by Employing Cryogenic Techniques

1972 ◽  
Vol 30 ◽  
pp. 410-411 ◽  
Author(s):  
Tokio Nei ◽  
Haruo Yotsumoto ◽  
Yoichi Hasegawa ◽  
Yuji Nagasawa
Keyword(s):  
Electron Microscopic Observation ◽  
Surface Structures ◽  
Specimen Preparation ◽  
Native State ◽  
Electron Microscopic ◽  
Biological Specimen ◽  
Specimen Holder ◽  
Cold Stage ◽  
Preparation Techniques ◽  
Scanning Electron

In order to observe biological specimens in their native state, that is, still containing their water content, various methods of specimen preparation have been used, the principal two of which are the chamber method and the freeze method.Using its recently developed cold stage for installation in the pre-evacuation chamber of a scanning electron microscope, we have succeeded in directly observing a biological specimen in its frozen state without the need for such conventional specimen preparation techniques as drying and metallic vacuum evaporation. (Echlin, too, has reported on the observation of surface structures using the same freeze method.)In the experiment referred to herein, a small sliced specimen was place in the specimen holder. After it was rapidly frozen by freon cooled with liquid nitrogen, it was inserted into the cold stage of the specimen chamber.

Imaging molecules adsorbed onto electrodes under potential control by scanning probe microscopy

1991 ◽  
Vol 49 ◽  
pp. 376-377 ◽  
Author(s):  
N.J. Tao ◽  
J.A. DeRose ◽  
P.I. Oden ◽  
S.M. Lindsay
Keyword(s):  
Surface Charge ◽  
Environmental Effects ◽  
Scanning Probe Microscopy ◽  
Statistical Significance ◽  
Electrochemical Methods ◽  
Surface Structures ◽  
Scanning Probe ◽  
Potential Control ◽  
Afm Imaging ◽  
Special Circumstances

Clemmer and Beebe have pointed out that surface structures on graphite substrates can be misinterpreted as biopolymer images in STM experiments. We have been using electrochemical methods to react DNA fragments onto gold electrodes for STM and AFM imaging. The adsorbates produced in this way are only homogeneous in special circumstances. Searching an inhomogeneous substrate for ‘desired’ images limits the value of the data. Here, we report on a reversible method for imaging adsorbates. The molecules can be lifted onto and off the substrate during imaging. This leaves no doubt about the validity or statistical significance of the images. Furthermore, environmental effects (such as changes in electrolyte or surface charge) can be investigated easily.

Ultrathin Platinum Crystal Surface Structures

1985 ◽  
Vol 43 ◽  
pp. 394-395
Author(s):  
R. L. Hines
Keyword(s):  
Crystal Surface ◽  
Surface Structures ◽  
Platinum Surface ◽  
Platinum Surfaces ◽  
Resolution Level ◽  
Experimental Facilities ◽  
Carbon Backing ◽  
Mesh Grid ◽  
Atom Layer

The importance of atom layer terraces or steps on platinum surfaces used for catalysis as discussed by Somorjai justifies an extensive investigation of the structure of platinum surfaces through electron microscopy at the atomic resolution level. Experimental and theoretical difficulties complicate the quantitative determination of platinum surface structures but qualitative observation of surface structures on platinum crystals is now possible with good experimental facilities.Ultrathin platinum crystals with nominal 111 orientation are prepared using the procedure reported by Hines without the application of a carbon backing layer. Platinum films with thicknesses of about ten atom layers are strong enough so that they can be mounted on grids to provide ultrathin platinum crystals for examination of surface structure. Crystals as thin as possible are desired to minimize the theoretical difficulties in analyzing image contrast to determine structure. With the current preparation procedures the crystals frequently cover complete openings on a 400 mesh grid.

Characterization of machined polystyrene foam

1989 ◽  
Vol 47 ◽  
pp. 372-373
Author(s):  
C. W. Price ◽  
E. F. Lindsey ◽  
R. M. Franks ◽  
M. A. Lane
Keyword(s):  
Surface Finish ◽  
Cell Walls ◽  
Surface Structures ◽  
Efficient Technique ◽  
Low Density ◽  
Polystyrene Foam ◽  
Planar Surfaces ◽  
Machining Characteristics

Diamond-point turning is an efficient technique for machining low-density polystyrene foam, and the surface finish can be substantially improved by grinding. However, both diamond-point turning and grinding tend to tear and fracture cell walls and leave asperities formed by agglomerations of fragmented cell walls. Vibratoming is proving to be an excellent technique to form planar surfaces in polystyrene, and the machining characteristics of vibratoming and diamond-point turning are compared.Our work has demonstrated that proper evaluation of surface structures in low density polystyrene foam requires stereoscopic examinations; tilts of + and − 3 1/2 degrees were used for the stereo pairs. Coating does not seriously distort low-density polystyrene foam. Therefore, the specimens were gold-palladium coated and examined in a Hitachi S-800 FESEM at 5 kV.

Sign in / Sign up

Export Citation Format

Share Document