Effect of Zircon Content on the Microstructure and Physical Properties of Chamotte Refractories

2016 ◽  
Vol 697 ◽  
pp. 604-607
Author(s):  
Ruo Fei Xiang ◽  
Yuan Bing Li ◽  
Shu Jing Li ◽  
Xin Yan Ma ◽  
Ya Wei Li ◽  
...  

In this work, chamotte with dispersions of up to 30wt% zircon is sintered at 1500 °C to investigate the effect of zircon content on the microstructure and physical properties of chamotte refractories. The microstructure and physical properties of samples are investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS), three-point bending and dilatometer. The result shows that the main phases of chamotte with and without sintering at 1500 °C are mullite and cristobalite, the addition of zircon has no impact on the main phase compositions of chamotte matrix. For the sintered samples, zircon grains are wrapped with glass and no obvious bonding are detected between the interface of zircon and mullite grains. Increasing zircon content leads to the increase in bulk density and has a negative effect on the flexural strength, besides, linear thermal expansion ratio decreases as the zircon content increases.

2014 ◽  
Vol 353 ◽  
pp. 137-142
Author(s):  
V.A. Bykov ◽  
T.V. Kulikova ◽  
K.Yu. Shunyaev ◽  
A.B. Shubin

The thermal and microstructural properties of five copper-gallium-tin alloys (Cu-Ga-Sn) and two important intermetallic compounds Cu3Sn and CuGa2 have been investigated by dilatometry, scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction. The temperature dependence of thermal expansion and coefficient of linear thermal expansion (CLTE) were obtained.


2015 ◽  
Vol 655 ◽  
pp. 68-71
Author(s):  
Yuan Yuan Zhu ◽  
Jin Jia ◽  
Ai Guo Zhou ◽  
Li Bo Wang ◽  
Qing Feng Zan

Layered ternary compounds Ti3SiC2combines attractive properties of both ceramics and metals, and has been suggested for potential engineering applications. Near-fully dense Ti3SiC2bulks were sintered from commercial Ti3SiC2powders by hot press at 1350°C-1600°C for 60-120min under Ar atmosphere in this paper. The phase compositions and morphology of the as-prepared samples were evaluated by X-Ray diffraction (XRD) and scanning electron microscopy (SEM). And the mechanical properties were measured by Three-Point bending method. It was found that the Ti3SiC2had only a little of decomposition at sintering temperature above 1350°C. And effects of sintering temperature and holding time on the morphology of the bulk Ti3SiC2are not obvious. Relative density of 98% and flexural strength of 480MPa were obtained for the Ti3SiC2samples sintered at 30MPa and 1400°C for 90min.


2021 ◽  
Vol 10 (4) ◽  
pp. 84-87
Author(s):  
Maya Sari ◽  
Yolanda Rati ◽  
Tetty Marta Linda ◽  
Yanuar Hamzah ◽  
Ari Sulistyo Rini

 Abstrak. Dalam rangka mengurangi pemakaian bahan kimia berbahaya, kini telah mulai dikembangkan penggunaan bahan alami pada proses pembentukan nanopartikel. Pada penelitian ini, biosintesis nanopartikel ZnO dilakukan menggunakan ekstrak kulit Ananas comosus sebagai agen capping sekaligus agen pereduksi. Seng nitrat digunakan sebagai prekursor dari ion seng, sedangkan kulit nanas dibuat menjadi ekstrak untuk dimanfaatkan kandungan antioksidannya. Sampel ZnO dipelajari sifat fisisnya dari hasil karakterisasi X-ray diffraction (XRD), scanning electron microscopy (SEM) dan spektroskopi UV-Vis. Berdasarkan pola XRD, nanopartikel ZnO memberikan fasa kristal heksagonal wurtzite dengan ukuran kristal 14 nm. Morfologi SEM masing-masing sampel didapatkan berbentuk bunga atau micro-nanoflower dengan ukuran diameter rata-rata 510 nm dan 560 nm untuk sampel 0,01 M dan 0,025 M. Hasil spektrum absorbansi UV-Vis menunjukkan peningkatan puncak penyerapan cahaya dengan penambahan konsentrasi seng nitrat. Berdasarkan informasi sifat fisis ini, sampel ZnO berpotensi diaplikasikan sebagai material fotokatalis.Abstract. In order to reduce the use of hazardous chemicals, the use of natural ingredients has now been developed in the process of forming nanoparticles. In this study, biosynthesis of ZnO nanoparticles was carried out using Ananas comosus peel extract as capping agent and reducing agent. Zinc nitrate was used as a precursor to zinc ion. The physical properties of ZnO samples were studied from the characterization result of scanning electron microscopy (SEM), UV-Vis spectroscopy, and X-ray diffraction (XRD). The SEM morphology of each different sample was obtained in the form of micro-nanoflower with an average diameter  of 510 nm and 560 nm for 0.01 M and 0.025 M samples, respectively. The UV-Vis absorbance spectrum results showed an increase in the light absorption peak as  zinc nitrate concentration increased. According to the XRD pattern, the ZnO nanoparticles possessed an hexagonal wurtzite crystal phase with a crystal size of 14 nm. Based on this information on physical properties, the ZnO sample has the potential to be applied as a photocatalyst material.


2012 ◽  
Vol 463-464 ◽  
pp. 1497-1500
Author(s):  
Lin Lin Yang ◽  
Yong Gang Wang ◽  
Yu Jiang Wang

Na0.5Bi0.5TiO3 microcubes with the side size ca. 20-30um were successfully fabricated by a Cr3+-assisted hydrothermal method. The obtained samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results show that Cr3+ played a significant role in the formation of Na0.5Bi0.5TiO3 microcubes. Possible mechanisms for the growth of Na0.5Bi0.5TiO3 microcubes are discussed. The results presented in this study would be important in investigating the correlation between morphology and basic physical properties, and may offer a route to control the morphology and size of crystals.


2019 ◽  
Vol 15 (2) ◽  
pp. 315
Author(s):  
Agus Wedi Pratama ◽  
Bambang Piluharto ◽  
Dwi Indarti ◽  
Tanti Haryati ◽  
Hardian Susilo Addy

<p>Selulosa merupakan salah satu biopolimer melimpah yang banyak digunakan dalam berbagai bidang seperti kertas, energi dan material komposit. Hidrofilisitas, dapat diperbaharui, ramah lingkungan dan aman adalah sifat-sifat selulosa yang dapat berpotensi menjadi material maju. Berdasarkan sifat-sifatnya, selulosa dapat dimodifikasi untuk menghasilkan sifat fungsional yang sesuai dengan aplikasinya. Dalam penelitian ini, selulosa mikrokristalin (MCC) dimodifikasi melalui metode hidrolisis asam. Prinsip metode ini adalah penghilangan bagian <em>amorf</em> pada selulosa oleh asam, meninggalkan bagian kristal. Selain itu, ketika asam digunakan sebagai agen hidrolisis, maka akan menghasilkan muatan permukaan pada selulosa. Dalam penelitian ini, pengaruh berbagai konsentrasi asam pada struktur kimia, kristalinitas, morfologi dan muatan permukaan telah dikaji. Perubahan struktur selulosa dianalisis menggunakan <em>Fourier Transform Infra Red </em>(FTIR), kristalinitas menggunakan <em>X-ray Diffraction</em> (XRD), morfologi menggunakan <em>Scanning Electron Microscopy</em> (SEM) dan muatan permukaan menggunakan titrasi konduktomteri. Hasil analisis FTIR menunjukkan masuknya gugus sulfat pada struktur selulosa. Analisis XRD menunjukkan peningkatan kristallinitas dalam selulosa termodifikasi seiring bertambahnya konsentrasi asam. Hasil analisis morfologi menunjukkan partikel dalam selulosa termodifikasi (CM) lebih tersebar daripada MCC. Analisis titrasi konduktometri menunjukkan bahwa mengalami peningkatan muatan permukaan pada CM seiring dengan bertambahnya konsentrasi asam. Oleh karena itu, dapat disimpulkan bahwa pengaruh konsentrasi asam sulfat pada hidrolisis selulosa memberikan dampak yang signifikan pada sifat fisik dan muatan permukaan.</p><p><strong>Effect of Acid Concentration on Physical Properties and Surface charge of Modified Cellulose</strong>. Cellulose is one of abundant biopolymer that many widely used in various applications such as paper, energy and composite material. Hydrophilicity, renewable, biodegradable, and safety are cellulose properties that can became potential of advance materials. In the utilization, cellulose can be modified its properties for different purposes. In this work, microcrystalline cellulose (MCC) was modified by acid hydrolysis method. The principle of this method is removed amorphous region of cellulose by acid and leaving crystalline phase. Moreover, when acid was used as hydrolyzing agent, it produce the surface charge on cellulose. In this research, the effect of various concentration of acid on the chemical structure, crystallinity, morphology and surface charge have studied. The chemical structures were analyzed using Fourier Transform Infra Red (FTIR), crystallinity using X-ray Diffraction (XRD), morphology using Scanning Electron Microscopy (SEM), and surface charge using titration conductometric. The FTIR analysis result has successfully showed the entry of sulfate groups on the cellulose structure. The XRD analysis showed increasing crystallinity in Cellulose Modified (CM) with increase acid concentration. By morphology analysis, particles in CM more disperse than MCC. Analysis of conductometric titration shows that there is an increase in surface charge in CM as acid concentration increases. Thus, the effect of sulfuric acid concentration on hydrolysis of cellulose has a significant impact on physical properties and surface charge.</p>


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.


Sign in / Sign up

Export Citation Format

Share Document