Preparation and Characterization of Nanometer Gallium Nitride by Gas-Solid Reaction

2015 ◽  
Vol 1118 ◽  
pp. 97-102
Author(s):  
Kai Ji He ◽  
Shu Cai Wang ◽  
Kai Ming Wang

Firstly, nano Gallium oxide(Ga2O3), as raw material of nano Gallium nitride(GaN), was prepared by special liquid-phase precipitation method. Subsequently,nano GaN powder was prepared by ammonia solution method through self-made experimental apparatus,and characterized by XRD and TEM methods. By controlling reaction temperature, reaction time and nitrogen flow,optimum parameters were determined to prepare nano GaN powder. Result shows that nano GaN powder, which is high purity and small particle, Can be prepared at 1000°C~1200°C holding above 2h and 100L/h flow

2020 ◽  
Vol 197 ◽  
pp. 08021
Author(s):  
Francesca Merli ◽  
Elisa Belloni ◽  
Cinzia Buratti

The work was developed in the ReScaLe FiAer project framework, funded by the Fondazione Cassa di Risparmio di Perugia. It is focused on the identification and collection of multiple high quality wood waste from a local window manufacturer. Three types of wood were available, from different tree species (pine, oak, and mahogany) and sizes (pieces of wood, mixed coarse chips, and mixed fine chips). Preliminary analyses were performed in order to evaluate the properties of the raw material. For each type of wood, eco-sustainable panels (300x300 mm2) were assembled by gluing. Multiple tests were carried out in order to identify the optimal mixtures and to ensure a good mechanical resistance with the minimum adhesive use. Panels were assembled by using vinyl glue, easily available and cheap, and flour glue, with a lower environmental impact and safe for people’s health. The thermal conductivity of the panels was measured by means of the Small Hot Box experimental apparatus: it varies in the 0.071-0.084 W/mK range, at an average temperature of 10°C, depending on the tree species and regardless of the type of adhesive used. Furthermore, 100-mm diameter cylindrical samples with two different thicknesses for each type of wood and glue were fabricated, in order to investigate their acoustic behaviour in an impedance tube. The use of flour glue improves the sound absorption and insulation performance of the samples.


2014 ◽  
Vol 599-601 ◽  
pp. 118-123
Author(s):  
Xie Bin Zhu ◽  
Jing Chen ◽  
Zhong Jia Huang

Antimony doped tin oxide (ATO) Nano powder was prepared by co-precipitation method, selecting SnCl4 • 5H2O and SbCl3 as the main raw material, citric acid as dispersant, ammonia solution (1:3) as precipitant, which was characterized, analyzed and tested by XRD, SEM, and digital conductivity meter. The optimum technological condition is that evenly-scattered powder whose crystalline structure is rutile, particle is sphere, size is about 10nm and conductivity is 1.32 ×102 µs/cm can be obtained when the reaction temperature is 60°C, Sb doping ratio is 10%, pH value is 2, calcinations temperature are 600°C and calcinations time are 2 hours.


2013 ◽  
Vol 668 ◽  
pp. 331-334 ◽  
Author(s):  
Fu Liang Zhu ◽  
Yan Shuang Meng

NiO nanowires have been synthesized at the water bath via single-phase precipitation, using NiSO4·6H2O as nickel salts, NH3·H2O and H2C2O4·2H2O as precipitation agents and H2O as solvent. It has been measured by DSG/TG, X-ray diffiration (XRD) and scanning electron microscope (SEM). The results of the DSC/TG show that the precursor is completely decomposed under 400°C. The results of the XRD show that NiO nanowires are cube crystal structure. The diffraction peaks are in 37.3°, 43.3° and 62.9°, which are consistent with normal pattern. The optimum parameters are detemined in this system as: pH values of solution 8.0, reaction temperature 60°C, roasting temperature 400°C. The length-radius proportion of NiO nanowires prepared is greater than 20 under optimum conditions.


2020 ◽  
Vol 3 (1) ◽  
pp. 30-33
Author(s):  
Muthulakshmi M ◽  
Madhumitha G

Nanotechnology is a field of applied science focused on design, synthesis and characterization of nanomaterials. The nickel and magnesium have improved their applications in transparent electrodes and nano electronics. In addition, magnesium oxide has moisture resistance and high melting point properties. In the present work has been carried out in the development of green crystalline powder of nickel doped magnesium oxide nanoparticles by Co-precipitation method, from the mixture of nickel chloride and magnesium chloride with KOH as solvent. From the XRD results, crystalline size of the particle can be observed. Spherical structure of Ni doped MgO nanoparticles were indicated by SEM results and powdered composition of samples were obtained from FTIR. EDAX represents the peak composition of the nanoparticle. The above analytical techniques have confirmed that the Ni doped MgO nanoparticles obtained from the mixture of NiCl2 and MgCl2.


Fluids ◽  
2021 ◽  
Vol 6 (5) ◽  
pp. 178
Author(s):  
Souhail Maazioui ◽  
Abderrahim Maazouz ◽  
Fayssal Benkhaldoun ◽  
Driss Ouazar ◽  
Khalid Lamnawar

Phosphate ore slurry is a suspension of insoluble particles of phosphate rock, the primary raw material for fertilizer and phosphoric acid, in a continuous phase of water. This suspension has a non-Newtonian flow behavior and exhibits yield stress as the shear rate tends toward zero. The suspended particles in the present study were assumed to be noncolloidal. Various grades and phosphate ore concentrations were chosen for this rheological investigation. We created some experimental protocols to determine the main characteristics of these complex fluids and established relevant rheological models with a view to simulate the numerical flow in a cylindrical pipeline. Rheograms of these slurries were obtained using a rotational rheometer and were accurately modeled with commonly used yield-pseudoplastic models. The results show that the concentration of solids in a solid–liquid mixture could be increased while maintaining a desired apparent viscosity. Finally, the design equations for the laminar pipe flow of yield pseudoplastics were investigated to highlight the role of rheological studies in this context.


Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1411
Author(s):  
José Luis P. Calle ◽  
Marta Ferreiro-González ◽  
Ana Ruiz-Rodríguez ◽  
Gerardo F. Barbero ◽  
José Á. Álvarez ◽  
...  

Sherry wine vinegar is a Spanish gourmet product under Protected Designation of Origin (PDO). Before a vinegar can be labeled as Sherry vinegar, the product must meet certain requirements as established by its PDO, which, in this case, means that it has been produced following the traditional solera and criadera ageing system. The quality of the vinegar is determined by many factors such as the raw material, the acetification process or the aging system. For this reason, mainly producers, but also consumers, would benefit from the employment of effective analytical tools that allow precisely determining the origin and quality of vinegar. In the present study, a total of 48 Sherry vinegar samples manufactured from three different starting wines (Palomino Fino, Moscatel, and Pedro Ximénez wine) were analyzed by Fourier-transform infrared (FT-IR) spectroscopy. The spectroscopic data were combined with unsupervised exploratory techniques such as hierarchical cluster analysis (HCA) and principal component analysis (PCA), as well as other nonparametric supervised techniques, namely, support vector machine (SVM) and random forest (RF), for the characterization of the samples. The HCA and PCA results present a clear grouping trend of the vinegar samples according to their raw materials. SVM in combination with leave-one-out cross-validation (LOOCV) successfully classified 100% of the samples, according to the type of wine used for their production. The RF method allowed selecting the most important variables to develop the characteristic fingerprint (“spectralprint”) of the vinegar samples according to their starting wine. Furthermore, the RF model reached 100% accuracy for both LOOCV and out-of-bag (OOB) sets.


Author(s):  
Caroline J. Sartori ◽  
Graciene S. Mota ◽  
Fábio Akira Mori ◽  
Isabel Miranda ◽  
Teresa Quilhó ◽  
...  

2020 ◽  
Vol 849 ◽  
pp. 113-118
Author(s):  
Yayat Iman Supriyatna ◽  
Slamet Sumardi ◽  
Widi Astuti ◽  
Athessia N. Nainggolan ◽  
Ajeng W. Ismail ◽  
...  

The purpose of this study is to characterize Lampung iron sand and to conduct preliminary experiments on the TiO2 synthesis which can be used for the manufacturing of functional food packaging. The iron sand from South Lampung Regency, Lampung Province that will be utilized as raw material. The experiment was initiated by sieving the iron sand on 80, 100, 150, 200 and 325 mesh sieves. Analysis using X-Ray Fluorescence (XRF) to determine the element content and X-Ray Diffraction (XRD) to observe the mineralization of the iron sand was conducted. The experiment was carried out through the stages of leaching, precipitation, and calcination. Roasting was applied firstly by putting the iron sand into the muffle furnace for 5 hours at a temperature of 700°C. Followed by leaching using HCl for 48 hours and heated at 105°C with a stirring speed of 300 rpm. The leaching solution was filtered with filtrate and solid residue as products. The solid residue was then leached using 10% H2O2 solution. The leached filtrate was heated at 105°C for 40 minutes resulting TiO2 precipitates (powder). Further, the powder was calcined and characterized. Characterization of raw material using XRF shows the major elements of Fe, Ti, Mg, Si, Al and Ca. The highest Ti content is found in mesh 200 with 9.6%, while iron content is about 80.7%. While from the XRD analysis, it shows five mineral types namely magnetite (Fe3O4), Rhodonite (Mn, Fe, Mg, Ca) SiO3, Quart (SiO2), Ilmenite (FeOTiO2) and Rutile (TiO2). The preliminary experiment showed that the Ti content in the synthesized TiO2 powder is 21.2%. The purity of TiO2 is low due to the presence of Fe metal which is dissolved during leaching, so that prior to precipitation purification is needed to remove impurities such as iron and other metals.


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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