Fabrication of Lead Barium Titanate Ceramics via Conventional Solid-State Mixed Oxide Technique

2008 ◽  
Vol 55-57 ◽  
pp. 209-212 ◽  
Author(s):  
Theerachai Bongkarn ◽  
P. Panya

(Pb0.925Ba0.075)TiO3 (PBT) ceramics have been prepared using a mixed oxide technique. The phase formation and morphology were studied in detail via X-ray diffraction (XRD) and scanning electron microscopy (SEM). The pure tetragonal perovskite structure was discovered with calcination temperatures above 800 oC. The percentage of perovskite phase and particle size tends to increase with the increasing of calcination temperatures. The PBT ceramics sintered at various temperatures belonged to a pure tetragonal perovskite phase. The average grain sizes increased from 0.90 to 6.44 µm with the increase of sintering temperatures from 1100 to 1200 oC. The highest density was obtained from the sample that sintered at 1150 and 1200 oC

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Li Zhao ◽  
Jingrun Ran ◽  
Zhan Shu ◽  
Guotian Dai ◽  
Pengcheng Zhai ◽  
...  

Ordered titanate nanoribbon (TNR)/SnO2films were fabricated by electrophoretic deposition (EPD) process using hydrothermally prepared titanate nanoribbon as a precursor. The formation mechanism of ordered TNR film on the fluorine-doped SnO2coated (FTO) glass was investigated by scanning electron microscopy (SEM). The effects of calcination temperatures on the phase structure and photocatalytic activity of ordered TNR/SnO2films were investigated and discussed. The X-ray diffraction (XRD) results indicate that the phase transformation of titanate to anatase occurs at 400°C and with increasing calcination temperature, the crystallization of anatase increases. At 600°C, the nanoribbon morphology still hold and the TiO2/SnO2film exhibits the highest photocatalytic activity due to the good crystallization, unique morphology, and efficient photogenerated charge carriers separation and transfer at the interface of TiO2and SnO2.


2020 ◽  
Vol 8 (1) ◽  
pp. 93-100
Author(s):  
Ediman Ginting Suka ◽  
◽  
Ira Sudarsono Putri ◽  
Reka Puspitasari ◽  
Reza Arsela ◽  
...  

Composite of rice husk and asphalt silica was carried out at a ratio of 1: 0.7; 1: 0.8 and 1: 0.9 and heated at 150oC for 3 hours. The characteristics of the phase structure, microstructure, and functional groups were analyzed using X-ray Diffraction (XRD), Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS) and Fourier Transform Infrared (FTIR), physical properties analysis (density, porosity) and mechanics (compressive strength). The XRD results showed that the phase in asphalt silica composites detected amorphous carbon at 2θ = 18º and amorphous silica with the amorphous silica peak shifted from 2θ = 22º to 2θ = 20º. Microstructure analysis shows that cracks and clusters are bigger with grain sizes of 7,742 µm, 8,495 µm and 10,921 µm respectively, and the sample composition shows percentage of silicon (Si), Oxygen (O) and sodium (Na), respectively. decreases and the percentage of carbon (C), sulfur (S) increases. The results of FTIR show that the functional groups of Si-OH, Si-O-Si and Si-O bonds are decreasing and the functional groups of C-H bonds are increasing. The addition of asphalt causes the value of density increases, the value of porosity and compressive strength decreases.


2014 ◽  
Vol 775-776 ◽  
pp. 410-414 ◽  
Author(s):  
Verônica Cristina Souza Diniz ◽  
Débora A. Vieira ◽  
Ruth Herta Goldsmith Aliaga Kiminami ◽  
Daniel Cornejo ◽  
Ana Cristina Figueiredo de Melo Costa

This study proposes to evaluate the influence of the variation of sintering temperature on microstructural characteristics and magnetic ferrite Ni0,5Zn0,5Fe2O4sintered by microwave energy. The samples were sintered at 900, 1000, 1100 and 1200°C for exposure time of 10 minutes, with rate 50°C/minutes and characterized by density and porosity, X-ray diffraction, scanning electron microscopy and magnetic measurements. The results indicate that the values of density and apparent porosity were 4.2, 4.5, 4.4 and 4.5 g/cm3and 3.4, 2.1, 2.2 and 2.4% for the sintering temperatures of 900, 1000, 1100 and 1200°C respectively. The formation of the ferrite phase Ni0,5Zn0,5Fe2O4been identified for all conditions of sintering, with grain sizes of 52, 62, 71 and 58nm and saturation magnetization values of 63, 68, 69 and 27 emu/g to temperatures sintering 900, 1000, 1100 and 1200°C respectively.


2013 ◽  
Vol 423-426 ◽  
pp. 885-889 ◽  
Author(s):  
Yi Gao Yuan ◽  
Jian Jun Ding ◽  
Yan Kun Wang ◽  
Wei Quan Sun

The carburizing heat treatments of ultrafine-grained WC-Co composites with sub-stoichiometric carbon content were carried out, and the microstructures of ultrafine-grained WC-Co carbides before and after treated were characterized by means of scanning electron microscopy and X-ray diffraction. The results show that the functionally gradient ultrafine-grained WC-Co hardmetals with a Co depleted surface and not comprising the η-phase can be fabricated by carburizing heat treatment. After heat treatment, WC grain sizes in materials are still at the ultrafine grade.


Author(s):  
Vicki L. Baliga ◽  
Mary Ellen Counts

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.


Author(s):  
Howard S. Kaufman ◽  
Keith D. Lillemoe ◽  
John T. Mastovich ◽  
Henry A. Pitt

Gallstones contain precipitated cholesterol, calcium salts, and proteins. Calcium (Ca) bilirubinate, palmitate, phosphate, and carbonate occurring in gallstones have variable morphologies but characteristic windowless energy dispersive x-ray (EDX) spectra. Previous studies of gallstone microstructure and composition using scanning electron microscopy (SEM) with EDX have been limited to dehydrated samples. In this state, Ca bilirubinates appear as either glassy masses, which predominate in black pigment stones, or as clusters, which are found mostly in cholesterol gallstones. The three polymorphs of Ca carbonate, calcite, vaterite, and aragonite, have been identified in gallstones by x-ray diffraction, however; the morphologies of these crystals vary in the literature. The purpose of this experiment was to study fresh gallstones by environmental SEM (ESEM) to determine if dehydration affects gallstone Ca salt morphology.Gallstones and bile were obtained fresh at cholecystectomy from 6 patients. To prevent dehydration, stones were stored in bile at 37°C. All samples were studied within 4 days of procurement.


2016 ◽  
Vol 5 (1) ◽  
pp. 6
Author(s):  
Budi Setiawan ◽  
Erizal Zaini ◽  
Salman Umar

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.


2018 ◽  
Vol 21 (7) ◽  
pp. 495-500 ◽  
Author(s):  
Hassan A. Almarshad ◽  
Sayed M. Badawy ◽  
Abdalkarem F. Alsharari

Aim and Objective: Formation of the gallbladder stones is a common disease and a major health problem. The present study aimed to identify the structures of the most common types of gallbladder stones using X-ray spectroscopic techniques, which provide information about the process of stone formation. Material and Method: Phase and elemental compositions of pure cholesterol and mixed gallstones removed from gallbladders of patients were studied using energy-dispersive X-ray spectroscopy combined with scanning electron microscopy analysis and X-ray diffraction. Results: The crystal structures of gallstones which coincide with standard patterns were confirmed by X-ray diffraction. Plate-like cholesterol crystals with laminar shaped and thin layered structures were clearly observed for gallstone of pure cholesterol by scanning electron microscopy; it also revealed different morphologies from mixed cholesterol stones. Elemental analysis of pure cholesterol and mixed gallstones using energy-dispersive X-ray spectroscopy confirmed the different formation processes of the different types of gallstones. Conclusion: The method of fast and reliable X-ray spectroscopic techniques has numerous advantages over the traditional chemical analysis and other analytical techniques. The results also revealed that the X-ray spectroscopy technique is a promising technique that can aid in understanding the pathogenesis of gallstone disease.


2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Xiaojian Bai ◽  
Chen Jia ◽  
Zhigen Chen ◽  
Yuxuan Gong ◽  
Huwei Cheng ◽  
...  

AbstractWith exquisite design and unique style, the painted sculptures of Tutang Buddha and two attendants Buddha in Jingyin Temple are precious cultural heritages of China. The sculpture of Tutang Buddha, which was carved from a mound and painted by ancient craftsmen, was rarely found in ancient China. However, due to natural and human factors, the sculptures were severely damaged. Obviously, they require urgent and appropriate protection and restoration. In this study, samples taken from the sculptures were analysed through multiple analytical techniques, including scanning electron microscopy with energy dispersive spectrometry (SEM–EDS), Raman spectroscopy, X-ray diffraction (XRD), optical microscopy (OM) and granulometry. The analysis results enable us to infer the techniques used by the craftsmen in making the sculptures and provide a reliable evidence for the conservation and future protection of these and similar sculptures.


2012 ◽  
Vol 620 ◽  
pp. 314-319
Author(s):  
Nur Amira Mamat Razali ◽  
Fauziah Abdul Aziz ◽  
Saadah Abdul Rahman

Hardwood is wood from angiosperm trees. The characteristic of hardwood include flowers, endosperm within seeds and the production of fruits that contain the seeds. This paper aims to discuss the preparation and characterization of cellulose obtained from hardwood. The hardwood Merbau (Intsia bijuga) was chosen as raw material in this study. Alkaline treatment and delignification methods were used for the preparation of cellulose. Acid hydrolysis was employed to produce cellulose nanocrystal (CNC). The treated and untreated samples were characterized using x-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The final product, from both trated and untreated samples were then compared.


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