Solution-Based Synthesis of Hafnium Carbide (HfC) Powders

HfC-based precursors with a range of carbon/metal oxide ratios were prepared from polymerization and copolymerization of metal containing monomers during solution-based synthesis. Heat treatments were given to the precursors to produce HfC powders. FTIR was used to record the infra-red spectra of the preceramic powders. HfC powders were assessed using X-ray diffraction and scanning electron microscopy.

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PENGARUH PERBANDINGAN MOLAR Ca/P DALAM PEMBUATAN LAPISAN TIPIS KALSIUM FOSFAT DARI PREKURSOR Ca(NO3)2.4H2O MELALUI METODE SOL-GEL

Jurnal Katalisator ◽

10.22216/jk.v1i2.1741 ◽

2016 ◽

Vol 1 (2) ◽

Author(s):

Veni Dayu Putri

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Fourier Transform ◽

Calcium Phosphate ◽

Sol Gel ◽

Dip Coating ◽

X Ray Diffraction ◽

X Ray ◽

Infra Red ◽

Scanning Electron

ABSTRAK Pembuatan lapisan tipis kalsium fosfat dari kalsium nitrat tetrahidrad (Ca(NO3)2.4H2O) sebagai prekursor kalsium dan asam fosfat (H3PO4) sebagai prekursor fosfat dengan variasi perbandingan mol Ca/P 1.50 , 1.60 , 1.67 , 1.70 dan 1.80 melalui metode sol-gel telah dilakukan. Sol yang didapat dibakar pada suhu 1000oC sehingga terbentuk powder kalsium fosfat berwarna putih. Powder yang didapat dianalisis menggunakan Fourier Transform Infra Red Spectroscopy (FTIR), X-Ray Diffraction (XRD) dan Scanning Electron Microscopy (SEM). Analisis FTIR menunjukkan adanya serapan gugus PO43-, O-H, H2O, CO2, dan P2O74-. Difraksi sinar-X dari powder yang terbentuk memberikan puncak pada sudut 2θ yang berbeda yaitu Calsium Pyrophospate (Ca2P2O7) dan Hydroxyapatite HAP (Ca10(PO4)6(OH)2 pada perbandingan molar Ca/P 1.80 . Analisis SEM menghasilkan Hydroxyapatite dan Calsium Pyrophospate dengan distribusi partikel yang tidak merata dan berbentuk spheric. Proses pelapisan dilakukan pada plat kaca yaitu pada perbandingan mol Ca/P 1.80 menggunakan metode dip-coating dan kemudian dipanaskan pada suhu 400oC. Hasil analisa XRD pada lapisan kalsium fosfat memperlihatkan bahwa senyawa yang terbentuk berbentuk amorf. Sedangkan analisis menggunakan SEM memperlihatkan bahwa lapisan tipis kalsium fosfat memiliki morfologi permukaan yang halus, rapat, homogen dan berbentuk speric. Kata kunci : kalsium fosfat, hydroxyapatite, dip-coating, metode sol-gel ABSTRACT Preparation a thin layer of calcium phosphate using tetrahidrad calcium nitrate (Ca(NO3)2.4H2O) as a precursor of calcium and phosphoric acid (H3PO4) as a precursor of phosphate with a variation of the mole ratio Ca/P 1.50; 1.60, 1.67, 1.70 and 1.80 through the sol-gel method have been done. Sol obtained burned at a temperature of 1000oC to form white powder of calcium phosphate. Powder obtained were analyzed using Fourier Transform Infra Red Spectroscopy (FTIR), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). FTIR analysis showed absorption PO43- group, O-H, H2O, CO2, and P2O74-. X-ray diffraction from powder formed providing a peak at an angle 2θ different namely Calcium Pyrophospate (Ca2P2O7) and Hydroxyapatite HAP (Ca10(PO4)6(OH)2) at a molar ratio of Ca/P 1.80. Analysis of SEM produces Hydroxyapatite and Calcium Pyrophospate with particle distribution is uneven and shaped spheric. The coating process performed on glass plates with mole ratio of Ca/P 1.80 using a dip-coating and then heated at a temperature of 400oC. XRD analysis on a layer of calcium phosphate showed that the compound formed shaped amorphous. While using SEM analysis showed the morphology of thin layer of calcium phosphate are smooth, dense, homogeneous and shaped speric. Keywords : calcium phosphate, hydroxyapatite, dip-coating, sol-gel method

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PENGARUH PENAMBAHAN ABU SEKAM PADI TERHADAP STRUKTUR DAN SIFAT MEKANIK GEOPOLIMER BERBASIS FLY ASH

Jurnal Sains dan Pendidikan Fisika ◽

10.35580/jspf.v16i2.15984 ◽

2020 ◽

Vol 16 (2) ◽

pp. 171

Author(s):

Wahyuni Wahyuni ◽

Subaer Subaer ◽

Nurhayati Nurhayati

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Fourier Transform ◽

Fly Ash ◽

X Ray Diffraction ◽

X Ray ◽

Infra Red ◽

Scanning Electron

Telah dilakukan penelitian tentang geopolimer berbasis fly ash dengan penambahan abu sekam padi. Penelitian ini bertujuan untuk mengetahui struktur dan sifat mekanik geopolimer berbasis fly ash dengan penambahan abu sekam padi. Geopolimer berbasis fly ash dibuat dengan penambahan abu sekam padi 0%, 20% dan 40% menggunakan metode aktivasi alkali dan dipanaskan pada suhu 70℃ selama 2 jam. Struktur mikro dari sampel diketahui dengan menggunakan teknik X-Ray Diffraction (XRD) dan menggunakan Scanning Electron Microscopy (SEM). Gugus fungsi dari sampel diperoleh berdasarkan pengujian Fourier Transform Infra Red (FTIR). Sifat mekanik seperti Kuat tekan dari sampel diuji menggunakan Testing Mechine. Massa jenis, porositas dan kuat lentur dilakukan pengukuran terhadap sampel. Hasil penelitian menunjukkan diperoleh fase trydimate yang tertinggi pada sampel Geo FA+ASP (60+40)%. Hasil karakterisasi Scanning Elektron Microscopy (SEM) menunjukkan material penyusun sampel telah berikatan dengan baik walaupun sebagian kecil pertikel fly ash dan abu sekam padi masih terlihat dengan jelas. Gugus fungsi pembentuk geopolimer diperoleh pada stretching Si-O-Si dengan nilai gelombang antara 478-461cm-1 dan 791-781cm-1. Massa jenis tertinggi diperoleh pada sampel dengan penambahan 40% abu sekam padi dan porositas tertinggi diperoleh pada sampel tanpa penambahan abu sekam padi. Kuat tekan yang terbesar diperoleh dari sampel geopolimer berbasis fly ash tanpa penambahan abu sekam padi sedangkan kuat lentur tertingi diperoleh dari sampel geopolimer berbasis fly ash dengan penambahan abu sekam padi sebesar 40%.

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Pengaruh Konsentrasi Asam Terhadap Sifat Fisik dan Muatan Permukaan Selulosa Termodifikasi

ALCHEMY Jurnal Penelitian Kimia ◽

10.20961/alchemy.15.2.33756.315-328 ◽

2019 ◽

Vol 15 (2) ◽

pp. 315

Author(s):

Agus Wedi Pratama ◽

Bambang Piluharto ◽

Dwi Indarti ◽

Tanti Haryati ◽

Hardian Susilo Addy

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Fourier Transform ◽

Physical Properties ◽

Surface Charge ◽

Acid Concentration ◽

X Ray Diffraction ◽

X Ray ◽

Infra Red ◽

Scanning Electron

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 amorf 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 Fourier Transform Infra Red (FTIR), kristalinitas menggunakan X-ray Diffraction (XRD), morfologi menggunakan Scanning Electron Microscopy (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.Effect of Acid Concentration on Physical Properties and Surface charge of Modified Cellulose. 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.

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Identification of calcium oxalate crystals in dried or fixed tobacco leaf

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111550 ◽

1984 ◽

Vol 42 ◽

pp. 288-289

Author(s):

Vicki L. Baliga ◽

Mary Ellen Counts

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Calcium Oxalate ◽

Growth And Development ◽

Polarized Light ◽

Calcium Oxalate Crystals ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Scanning Electron

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.

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Environmental scanning electron microscopy of fresh human gallstones reveals new morphologies of precipitated calcium salts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131243 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1322-1323

Author(s):

Howard S. Kaufman ◽

Keith D. Lillemoe ◽

John T. Mastovich ◽

Henry A. Pitt

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Environmental Scanning Electron Microscopy ◽

Environmental Scanning ◽

X Ray Diffraction ◽

Calcium Salts ◽

Cholesterol Gallstones ◽

X Ray ◽

Ca Carbonate ◽

Scanning Electron

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.

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PENINGKATAN LAJU DISOLUSI ACYCLOVIR DENGAN METODE SISTEM DISPERSI PADAT MENGGUNAKAN POLOXAMER 188

SCIENTIA : Jurnal Farmasi dan Kesehatan ◽

10.36434/scientia.v5i1.61 ◽

2016 ◽

Vol 5 (1) ◽

pp. 6

Author(s):

Budi Setiawan ◽

Erizal Zaini ◽

Salman Umar

Keyword(s):

Electron Microscopy ◽

Thermal Analysis ◽

Scanning Electron Microscopy ◽

Fourier Transform ◽

Differential Thermal Analysis ◽

Fourier Transform Infrared ◽

X Ray Diffraction ◽

Poloxamer 188 ◽

X Ray ◽

Scanning Electron

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.

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Structural Characterization of Gallbladder Stones Using Energy Dispersive X-ray Spectroscopy and X-ray Diffraction

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207321666180913113803 ◽

2018 ◽

Vol 21 (7) ◽

pp. 495-500 ◽

Cited By ~ 1

Author(s):

Hassan A. Almarshad ◽

Sayed M. Badawy ◽

Abdalkarem F. Alsharari

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Energy Dispersive ◽

Spectroscopic Techniques ◽

X Ray Diffraction ◽

Major Health Problem ◽

X Ray ◽

Gallbladder Stones ◽

Pure Cholesterol ◽

Scanning Electron

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.

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Analytical study of Buddha sculptures in Jingyin temple of Taiyuan, China

Heritage Science ◽

10.1186/s40494-020-00471-3 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Xiaojian Bai ◽

Chen Jia ◽

Zhigen Chen ◽

Yuxuan Gong ◽

Huwei Cheng ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Analytical Study ◽

Energy Dispersive Spectrometry ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Ancient China ◽

X Ray ◽

Unique Style ◽

Scanning Electron

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.

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Preliminary Preparation and Characterization Studies of Cellulose from Merbau (Intsia bijuga)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.620.314 ◽

2012 ◽

Vol 620 ◽

pp. 314-319

Author(s):

Nur Amira Mamat Razali ◽

Fauziah Abdul Aziz ◽

Saadah Abdul Rahman

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Alkaline Treatment ◽

Raw Material ◽

X Ray Diffraction ◽

X Ray ◽

Preliminary Preparation ◽

Characterization Studies ◽

Scanning Electron

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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Research on compatibility and surface of high impact bio-based polyamide

High Performance Polymers ◽

10.1177/09540083211005511 ◽

2021 ◽

pp. 095400832110055

Author(s):

Yang Wang ◽

Yuhui Zhang ◽

Yuhan Xu ◽

Xiucai Liu ◽

Weihong Guo

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Differential Scanning Calorimetry ◽

Crystallization Behavior ◽

High Impact ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Scanning Electron

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.

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