scholarly journals Influence of Sintering Time on Superconducting Properties of Bi, Pb-2223 Compound Doped with Indium

2021 ◽  
Vol 2114 (1) ◽  
pp. 012066
Author(s):  
M M Abbas ◽  
A K Jassim

Abstract This work was performed to investigate the effect of sintering time on superconducting properties of Bi1.7In0.3Pb0.3Sr2Ca2Cu3O10+d samples prepared by solid state reaction method. The samples properties have been investigated structurally by X-ray diffraction and morphologically by scanning electron microscopy. Structural analysis showed that two superconducting phases coexist in the samples. High temperature Bi-2223 and low-temperature phase 2212 with orthorhombic structure for all samples. Four point probe method used to study the electrical properties of the samples and the results showed that increasing sintering time yields superconductor samples. The sintering time 140 h improves the microstructure of the superconductor and produces greater size platelets as well as leading to the highest TC value of 113 K and highest oxygen content value. Scanning electron microscopy shows increasing sintering time changed morphology of samples. Moreover plate grains of the high Bi-2223 phase appeared in most micrographs of the superconducting samples.

2015 ◽  
Vol 5 (01) ◽  
pp. 31
Author(s):  
Resky Irfanita ◽  
Asnaeni Ansar ◽  
Ayu Hardianti Pratiwi ◽  
Jasruddin J ◽  
Subaer S

The objective of this study is to investigate the effect of sintering temperature on the synthesis of SiC produced from rice husk ash (RHA) and 2B graphite pencils. The SiC was synthesized by using solid state reaction method sintered at temperatures of 750°C, 1000°C and 1200°C for 26 hours, 11.5 hours and 11.5 hours, respectively. The quantity and crystallinity level of SiC phase were measured by means of Rigaku MiniFlexII X-Ray Diffraction (XRD). The microstructure of SiC was examined by using Tescan Vega3SB Scanning Electron Microscopy (SEM). The XRD results showed that the concentration (wt%) of SiC phase increases with the increasing of sintering temperature. SEM results showed that the crystallinity level of SiC crystal is improving as the sintering temperature increases


1995 ◽  
Vol 09 (28) ◽  
pp. 3697-3713 ◽  
Author(s):  
S. A. SIDDIQI ◽  
BILQUEES AKHTAR ◽  
A. MAQSOOD

Six different compositions in ( Bi 1.5 Pb 0.5−x Sb x) Sr 2 Ca 2 Cu 3 O y (with x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5) have been prepared by the solid state reaction method. Sintering at different temperatures (between 800–860° C) and time periods has been carried out in order to study its effect on T c values. The samples have been characterized by x ray powder diffraction (XRD), Scanning Electron Microscopy (SEM) and measurement of resistance at various temperatures. The study reveals that the incorporation of Sb up to x = 0.2 promotes the formation of a high-T c 2223 phase and large sintering time helps in reducing the number of unwanted phases. Compositions with x ≥ 0.3 result in the formation of a new monoclinic "4441 phase" (along with 2223 and 2212 minor phases) which is non-superconducting down to 77 K. Sintering time at 860°C for samples with x = 0.0, 0.1, 0.2 and 0.3 affects the respective T c values and the maximum values observed are 94 K, 96 K, 100 K and 87 K, respectively. The samples with x = 0.4 and 0.5 do not superconduct up to 77 K.


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.


2021 ◽  
pp. 095400832110055
Author(s):  
Yang Wang ◽  
Yuhui Zhang ◽  
Yuhan Xu ◽  
Xiucai Liu ◽  
Weihong Guo

The super-tough bio-based nylon was prepared by melt extrusion. In order to improve the compatibility between bio-based nylon and elastomer, the elastomer POE was grafted with maleic anhydride. Scanning Electron Microscopy (SEM) and Thermogravimetric Analysis (TGA) were used to study the compatibility and micro-distribution between super-tough bio-based nylon and toughened elastomers. The results of mechanical strength experiments show that the 20% content of POE-g-MAH has the best toughening effect. After toughening, the toughness of the super-tough nylon was significantly improved. The notched impact strength was 88 kJ/m2 increasing by 1700%, which was in line with the industrial super-tough nylon. X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) were used to study the crystallization behavior of bio-based PA56, and the effect of bio-based PA56 with high crystallinity on mechanical properties was analyzed from the microstructure.


2012 ◽  
Vol 174-177 ◽  
pp. 508-511
Author(s):  
Lin Lin Yang ◽  
Yong Gang Wang ◽  
Yu Jiang Wang ◽  
Xiao Feng Wang

BiFeO3 polyhedrons had been successfully synthesized via a hydrothermal method. The as-prepared products were characterized by power X-ray diffraction (XRD) pattern, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The possible mechanisms for the formation of BiFeO3 polyhedrons were discussed. Though comparison experiments, it was found that the kind of precursor played a key role on the morphology control of BiFeO3 crystals.


Sign in / Sign up

Export Citation Format

Share Document