Otospongiosis: Morphologic and Microchemical Investigation after Naf-Treatment

1981 ◽  
Vol 89 (4) ◽  
pp. 646-650 ◽  
Author(s):  
Paul Bretlau ◽  
Hans Jørgen Hansen ◽  
Jean Causse ◽  
Jean-Bernard Causse

Element analysis of microareas of otospongiotic specimens is described. A total of 36 otospongiotic stapes are ultrasectioned without decalcification and examined using a transmission and a scanning electron microscope (STEM-mode). The latter was equipped with an energy dispersive x-ray analyzer. Twenty of the stapes came from patients who have had sodium fluoride (NaF) treatment (15 to 45 mg/day) for a minimum of 12 months. The otospongiotic stapes are classified as spongiotic and sclerotic according to their pathologic characteristics and state of mineralization. Using the Ca/P ratio as criterion—measured by the characteristic x-ray fluorescence—it was shown in a blind study that the NaF-treated otospongiotic stapes had a statistically higher Ca/P ratio, indicating that the fluoride may stabilize otospongiotic lesions, particularly the spongiotic type with unstable mineralization.

AMERTA ◽  
2020 ◽  
Vol 25 (1) ◽  
pp. 48-57
Author(s):  
Stephen Chia ◽  
Lutfi Yondri ◽  
Truman Simanjuntak

Abstract. This paper presents the results of a study to determine whether the obsidian artifacts found in Gua Pawon, Dago and Bukit Karsamanik in Bandung came from the well-known sources of Gunung Kendan in Nagreg, Kampung Rejeng in Garut or elsewhere. Obsidian artifacts for this study were obtained from earlier archaeological excavations at Gua Pawon and from chance finds at the sites of Dago and Bukit Karsamanik in Bandung. Samples of obsidian were also collected from the known obsidian sources in Gunung Kendan in Nagreg and Kampung Rejeng in Garut for comparative purposes.Analyses of these samples were done on a scanning electron microscope using the energy dispersive X-ray spectrometer at the University of Science Malaysia, Penang and the electron microprobe at the University of Malaya, Kuala Lumpur. Multi-element analysis was undertaken, and statistical procedures were performed on data obtained from the artifacts and the sources. The results of the study thus far suggested that the obsidian artifacts from Gua Pawon were made using obsidian obtained from both Gunung Kendan and Kampung Rejeng sources while those from Dago and Bukit Karsamanik have yet to be determined. More samples from all the known obsidian sources are needed to determine the variability within and between all the different sources. Temporally, the study also revealed that prehistoric humans at Gua Pawon exploited or used the same obsidian resources over several thousands of years. Abstrak. Tulisan ini membahas hasil studi tentang sumber bahan baku artefak obsidian yang ditemukan di Gua Pawon, Dago, dan Bukit Karsamanik, Bandung. Analisis dilakukan terhadap sejumlah artefak obsidian, temuan ekskavasi di Gua Pawon dan temuan permukaan di Situs Dago dan Bukit Karsamanik. Untuk perbandingan dilakukan juga analisis terhadap obsidian dari Gunung Kendan di Nagrek dan Kampung Rejeng di Garut, dua lokasi sumber obsidian di Jawa Barat.Analisis dilakukan dengan cara "scanning electron microscope", menggunakan "energy dispersive X-ray spectrometer" di Universitas Sains Malaysia, Penang dan "electron microprobe" di Universitas Malaya, Kuala Lumpur. Analisis multielemen dan perhitungan statistic dilakukan terhadap data yang diperoleh dari artefak dan bahan. Hasil studi memperlihatkan artefak obsidian dari Gua Pawon menggunakan bahan dari Gunung Kendan dan Kampung Rejeng, sementara artefak Dago dan Bukit Karsamanik belum diketahui sumbernya. Analisis terhadap bahan dari sumber-sumber lain sangat diperlukan untuk menentukan variabilitas di dalam dan di antarasumber-sumber yang berbeda. Untuk sementara, hasil studi memperlihatkan manusia prasejarah Gua Pawon mengeksploitasi dan menggunakan sumber-sumber obsidian yang sama selama beberapa ribu tahun.


Author(s):  
Marc H. Peeters ◽  
Max T. Otten

Over the past decades, the combination of energy-dispersive analysis of X-rays and scanning electron microscopy has proved to be a powerful tool for fast and reliable elemental characterization of a large variety of specimens. The technique has evolved rapidly from a purely qualitative characterization method to a reliable quantitative way of analysis. In the last 5 years, an increasing need for automation is observed, whereby energy-dispersive analysers control the beam and stage movement of the scanning electron microscope in order to collect digital X-ray images and perform unattended point analysis over multiple locations.The Philips High-speed Analysis of X-rays system (PHAX-Scan) makes use of the high performance dual-processor structure of the EDAX PV9900 analyser and the databus structure of the Philips series 500 scanning electron microscope to provide a highly automated, user-friendly and extremely fast microanalysis system. The software that runs on the hardware described above was specifically designed to provide the ultimate attainable speed on the system.


2013 ◽  
Vol 19 (S2) ◽  
pp. 692-693
Author(s):  
P. Trimby

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.


2021 ◽  
Vol 12 (1) ◽  
pp. 13-18
Author(s):  
Wayan Sujana

Nitridisasi merupakan suatu proses perlakuan panas termokimia yang dimana nitrogen dan amonia didifusikan kepermukaan material (ferro and non-ferro) pada temperatur 500-6000C sehingga membentuk pengerasan kulit akibat terbentuknya lapisan nitrida paduan pada permukaan. Namun pengerasan permukaan ditentukan oleh paduan dari material yang dilakukan proses nitridisasi.Tujuan Nitridisasi adalah untuk memperbaiki ketahanan aus, meningkatkan ketahanan lelah, dan memperbaiki ketahanan tehadap korosi. Proses nitidisasi ini juga dapat mengganti jenis perlakuan panas lain yang menekankan performance yang baik. Pada penelitian ini akan memanfaatkan besi cor nodular yanga akan diproses nitridisasi menggunakan fluidised bed furnace. Pada penelitian ini menggunakan pengujian distribusi kekerasan (metode vickers) untuk mengamati sejauh mana nitrogen berdifusi pada permukaan spesimen, dan pengamatan struktur mikro dengan scanning electron microscope, energy dispersive X-Ray spectroscopy (SEM-EDS).Penelitian ini akan memberikan informasi fenonema proses nitridisasi pada besi cor nodular sehingga mendapatkan suatu analisis yang sesuai dengan metode sehingga menghasilkan kualitas kekerasan permukaan yang baik.


2021 ◽  
Vol 42 (1) ◽  
pp. 40-50
Author(s):  
P. Dhevagi ◽  
◽  
S. Priyatharshini ◽  
A. Ramya ◽  
M. Sudhakaran ◽  
...  

Aim: Removal of lead from wastewater using Azotobacter species and optimisation of various parameters to maximise the adsorption of lead by response surface methodology as a tool. Methodology: The bacterial isolate UBI-7 recovered from sewage water irrigated soil was examined for its biosorption potential towards lead. The lead removal efficiency of Azotobacter salinestris was studied with respect to metal concentration (50-250 mg l-1), contact time (24-120 hrs), and pH (4-8).Using response surface methodology, these factors were optimized and R2 value obtained was 0.9710 for lead ions, which indicates the validity of the model. Observation with Fourier Transform Infrared (FTIR), Scanning Electron Microscope imaging (SEM) and Energy Dispersive X-ray Spectroscopic analysis (EDX) were carried out to confirm lead biosorption by Azotobacter salinestris. Results: The lead tolerant bacterium isolated from sewage water irrigated soil (UBI-7) was recognized as Azotobacter salinestris by 16S rRNA based gene sequence analysis. The highest removal percentage of Pb (61.54) was 50 mg l-1 in 72 hrs equilibration period. Interaction effect between different levels of Pb and different contact time of the solution were found to be significant. Lead biosorption by the organism was confirmed by the changes in stretching intensities of functional groups as well as appearance of strong OH stretching at 3291.69 cm-1. Images obtained from Scanning Electron Microscope and Energy Dispersive X-ray Spectroscopic studies of the bacteria (UBI-7) before and after biosorption clearly indicated lead adsorption. Interpretation: Current study proves that the functional groups of Azotobacter salinestris are involved in lead biosorption from aqueous solution which was confirmed through FTIR.EDX analysis also elucidated the lead absorption by the bacterial cells. Hence, this could be effectively utilized for decontamination of lead from the polluted environment. Key words: Azotobacter salinestris, Biosorption, Lead, Response surface methodology


2011 ◽  
Vol 391-392 ◽  
pp. 1183-1188 ◽  
Author(s):  
Jian Hua Wang ◽  
Xing Ming Wang ◽  
Chun Mei Liu ◽  
Xu Ping Su ◽  
Chang Jun Wu ◽  
...  

The microstructure of the galvanized coating was investigated using scanning electron microscope equipped with energy dispersive X-ray spectroscope. The immersing and electrochemical corrosion tests were carried out to study the corrosion resistance of the galvanized coating. The addition of Bi in Zn-bath affects remarkably the morphology of the galvanized coating. The thickness of δ + ζ phase layer in the coating reaches the maximum when the content of Bi in Zn-bath is 0.5 wt.%. The corrosion resistance of the galvanized coating declines with the increase of the content of Bi.


Sign in / Sign up

Export Citation Format

Share Document