Novel Catalytic Systems Based on Platinum Catalysts

2020 ◽  
Vol 299 ◽  
pp. 1033-1037
Author(s):  
G. M. Kurunina ◽  
O.M. Ivankina ◽  
G. M. Butov

The paper presents a method for the production of 1% platinum catalysts containing oxides of rare-earth elements (REE); it also dwells upon the results of analyzing such catalysts by scanning electron microscopy (SEM), x-ray diffraction analysis (XDA), and thermal analysis (DTA-TGA).

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.


Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4171 ◽  
Author(s):  
Paweł Rutkowski ◽  
Jan Huebner ◽  
Adrian Graboś ◽  
Dariusz Kata ◽  
Dariusz Grzybek ◽  
...  

In this study, the influence of the addition of rare earth oxides on the phase composition and density of KNN piezoelectric ceramics was investigated. The initial powders of Na2CO3 and K2CO3 were dried at 150 °C for 2 h. Then, a powder mixture for synthesis was prepared by adding a stoichiometric amount of Nb2O5 and 5 and 10 wt % overabundance of Na2CO3. All powders were mixed by ball-milling for 24 h and synthesized at 950 °C. The phase composition of the reaction bed was checked by means of X-ray diffraction (XRD). It had an appearance of tetragonal and monoclinic K0.5Na0.5NbO3 (KNN) phases. Then, 1 and 2 wt % of Er2O3 and Yb2O3, were added to the mixture. Green samples of 25 mm diameter and 3 mm thickness were prepared and sintered by hot pressing at 1000 °C for 2 h under 25 MPa pressure. The final samples were investigated via scanning electron microscopy (SEM)-energy-dispersive X-ray spectroscopy (EDS), XRD, Rietveld, and ultrasonic methods. Phase analysis showed tetragonal and orthorhombic KNN phases, and a contamination of (K2CO3·1.5H2O) was present. The obtained KNN polycrystals had a relative density above 95%. Texturing of the material was confirmed as a result of hot pressing.


2013 ◽  
Vol 197 ◽  
pp. 137-142 ◽  
Author(s):  
Tomasz Rzychoń ◽  
Janusz Szala ◽  
Tomasz Kukiełka

In this paper the results of microstructural investigations and methodology of detection of intermetallic compounds were reported. The microstructural investigations included the light microscopy, scanning electron microscopy, chemical microanalysis and X-ray diffraction analysis. It was found that the microstructure of Mg-5Al-3Ca-0.7Sr-0.2Mn alloy consists of α-Mg, (Mg,Al)2Ca, Al3Mg13(Sr,Ca), Mg2Ca and Al2Ca intermetallic phases. The correct detection of these phases requires the high magnifications and a large number of measurements fields.


2000 ◽  
Vol 55 (9) ◽  
pp. 882-886 ◽  
Author(s):  
Martin Jansen ◽  
Sascha Vensky

The silver(I,II,III) oxide clathrate Ag7O8HCO3 was synthesized by anodic oxidation of silver(I) in a suspension of Ag2CO3 in an aqueous AgF solution. The title compound was characterized by single crystal X-ray diffraction (cubic, Fm3̄m, a = 9.8085(3) Å, Z = 4), scanning electron microscopy, thermal analysis, IR spectroscopy, 1H-solid state-NMR and measurement of the magnetic susceptibility


2012 ◽  
Vol 512-515 ◽  
pp. 1023-1027
Author(s):  
Ran Fang Zuo ◽  
Gao Xiang Du ◽  
Le Fu Mei ◽  
Wei Juan Guo ◽  
Jing Hui Liao

The main objective of this paper was to investigate the addition of iron tailing sintering brick production, in the presence of clay, coal refuses and bentonite. Mixtures containing raw materials of sintering brick and iron tailings were prepared at different proportions (up to 55 wt %), fired at 980°C. Freeze/thaw durability, drying and firing shrinkages were investigated as well as the loss on ignition, bulk density and compressive strength of the fired samples. Their mechanical and microstructure properties were also investigated by differential thermal analysis (DTA/TG), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed that compressive strengths of the brick samples are higher than that required by the standards MU15 of GB5101-2003, up to 21.79Mpa with 40% iron tailings corresponding to its higher bulk density completely. Moreover, the results showed that it has such advantages as no lime blowing, uniform color, good freeze/thaw resistance and slight universal frost.


2014 ◽  
Vol 577 ◽  
pp. 62-65
Author(s):  
Chun Lian Hu ◽  
Shang Lin Hou

The microstructure of rare earth NiCrMoY alloy manufactured by atomization and oxygen-acetylene flame spray and high frequency induction remelting technique is investigated by a combination of scanning electron microscopy (SEM), energy spectrum, X-ray diffraction meter (XRD). The results indicate that Microstructure of NiCrMoY alloy coatings are finer and bulk-and needle-like hard Metallograph are precipitated, a new phase MoB is produced.


Sign in / Sign up

Export Citation Format

Share Document