Extraction of Boron from Ludwigite Ore: Mechanism of Soda-Ash Roasting of Lizardite and Szaibelyite

Ludwigite ore is a typical low-grade boron ore accounting for 58.5% boron resource of China, which is mainly composed of magnetite, lizardite and szaibelyite. During soda-ash roasting of ludwigite ore, the presence of lizardite hinders the selective activation of boron. In this work, lizardite and szaibelyite were prepared and their soda-ash roasting behaviors were investigated using thermogravimetric-differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), and scanning electron microscope and energy dispersive spectrometer (SEM-EDS) analyses, in order to shed light on the soda-ash activation of boron within ludwigite ore. Thermodynamics of Na2CO3-MgSiO3-Mg2SiO4-Mg2B2O5 via FactSage show that the formation of Na2MgSiO4 was preferential for the reaction between Na2CO3 and MgSiO3/Mg2SiO4. While, regarding the reaction between Na2CO3 and Mg2B2O5, the formation of NaBO2 was foremost. Raising temperature was beneficial for the soda-ash roasting of lizardite and szaibelyite. At a temperature lower than the melting of sodium carbonate (851 °C), the soda-ash roasting of szaibelyite was faster than that of lizardite. Moreover, the melting of sodium carbonate accelerated the reaction between lizardite with sodium carbonate.

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Effect of Cooling Rates on the Solidification and Microstructure of Rapidly Solidified Mg70.8Zn28Nd1.2 Quasicrystal Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.898.246 ◽

2017 ◽

Vol 898 ◽

pp. 246-253

Author(s):

Xing Jing Ge ◽

Xin Ying Teng ◽

Shu Min Xu ◽

Jin Yang Zhang

Keyword(s):

Electron Microscopy ◽

Phase Transition ◽

Thermal Analysis ◽

Energy Dispersive Spectrometer ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Cooling Rates ◽

X Ray ◽

Rapidly Solidified ◽

Scanning Electron

The influence of cooling rates on the solidification and microstructure of rapidly solidified quasicrystal alloy Mg70.8Zn28Nd1.2(at.%) was investigated. The microstructure, phase constitution, phase transition and phase structure of the alloys were examined by means of scanning electron microscopy, x-ray diffraction, energy dispersive spectrometer, differential scanning calorimetry. The experimental results showed that the phase composition of as-cast Mg70.8Zn28Nd1.2 alloy includes quasicrystal I-phase and Mg7Zn3 phase. For the rapidly solidified alloy ribbons, when the speed is not higher than 400 r/min, the microstructure includes I-phase, Mg7Zn3 phase and α-Mg phase. When the speed is at the range of 400-2000r/min, the Mg7Zn3 phase disappears and only quasicrystal with α-Mg phase exist. With the increase of cooling rate, the grain size decreases and there are a large number of microcrystals in the microstructure. When the speed reaches higher than 2500 r/min, amorphous phase appeared. Differential thermal analysis showed that quasicrystal exist at about 340°C.

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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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Development of an Oxcarbazepine Solid Dispersion Using Skimmed Milk to Improve the Solubility and Dissolution Profile

International Journal of Pharmaceutical Sciences and Drug Research ◽

10.25004/ijpsdr.2019.110509 ◽

2019 ◽

Vol 11 (05) ◽

Author(s):

M. Shah ◽

D. Patel

Keyword(s):

Electron Microscopy ◽

Solid Dispersion ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Infra Red ◽

Crystalline Nature ◽

Skimmed Milk ◽

Scanning Electron

Oxcarbazepine has low solubility and low oral bioavailability, so it’s a challenge to formulate suitable dosage form. In this present investigation, to improve the dissolution rate and solubility, skimmed milk is used as a carrier. Physical mixers were prepared using various drugs to carrier ratio and spray drying technology was used to develop solid dispersion with the carrier. Various techniques were used to characterize the solid dispersion immediately after they were made which includes differential scanning calorimetry, scanning electron microscopy, fourier transform infra- red spectroscopy, X-ray diffraction and in-vitro dissolution profiles. The differential scanning calorimetry thermograms of raw drug indicated of its anhydrous crystalline nature. In thermograms of solid dispersion, the characteristic peak was absent suggesting the change from crystalline nature to amorphous form. X-ray diffraction confirmed those results. X-ray diffraction results of raw drug showed highly intense peak characteristic of its crystalline nature where solid dispersion showed less intense, more diffused peak indicating the change in crystalline form. Fourier transforms infra-red spectroscopy studies showed there was no interaction between drug and carrier. Scanning electron microscopy support the amorphous nature of mixer. The whole formulation showed distinct enhancement in the drug release behavior and solubility. The optimum oxcarbazepine to skimmed milk ratio 1:3 enhances the in-vitro drug release by 3.5 fold and also show distinct increase in solubility. It was concluded that for improvement of solubility of poorly water soluble oxcarbazepine, skimmed milk powder as a carrier can be utilize very well.

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MICROSTRUCTURE AND BLUE PHOTOLUMINESCENCE OF HYDROGENATED SILICON CARBONITRIDE THIN FILMS

Surface Review and Letters ◽

10.1142/s0218625x18501779 ◽

2019 ◽

Vol 26 (04) ◽

pp. 1850177 ◽

Cited By ~ 1

Author(s):

YINQIAO PENG ◽

JICHENG ZHOU ◽

GUIBIN LEI ◽

YUANJU GAN ◽

YUEFENG CHEN

Keyword(s):

Thin Films ◽

Network Structure ◽

Energy Dispersive Spectrometer ◽

Silicon Carbonitride ◽

X Ray Diffraction ◽

Hydrogenated Silicon ◽

X Ray ◽

Atomic Force ◽

Scanning Electron ◽

Blue Photoluminescence

Hydrogenated silicon carbonitride (SiCN:H) thin films were deposited by sputtering of silicon carbide target in hydrogen-doped argon and nitrogen atmospheres. The properties of the SiCN:H films were analyzed by scanning electron microscopy with energy dispersive spectrometer, atomic force microscope, Fourier transform infrared spectroscopy, X-ray diffraction and fluorescence spectrophotometer. No distinct crystal was formed in the SiCN:H films as-deposited and annealed at 600∘C and 800∘C. The SiCN:H films were mainly composed of Si–N, Si–C, Si–O, C–C, C–N, C[Formula: see text]N, N–Hn bonds and SiCxNy network structure. The strong blue photoluminescence observed from the SiCN:H film annealed at 600∘C was attributed to SiCxNy network structure.

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Liberation Characteristics of Ta–Sn Ores from Penouta, NW Spain

Minerals ◽

10.3390/min10060509 ◽

2020 ◽

Vol 10 (6) ◽

pp. 509

Author(s):

Pura Alfonso ◽

Sarbast Ahmad Hamid ◽

Hernan Anticoi ◽

Maite Garcia-Valles ◽

Josep Oliva ◽

...

Keyword(s):

White Mica ◽

Low Grade ◽

Economic Interest ◽

X Ray Diffraction ◽

Nw Spain ◽

X Ray ◽

Mineral Associations ◽

Ore Minerals ◽

Automated Mineralogy ◽

Scanning Electron

The strategic importance of tantalum and its scarcity in Europe makes its recovery from low grade deposits and tailings interesting. In Penouta, the contents of Ta and Sn in old tailings from an Sn mine are of economic interest. Due to the relatively low grade of Ta of around 100 ppm, a detailed study of the mineralogy and liberation conditions is necessary. In this study, the mineralogy and the liberation characteristics of Sn and Ta ores of the Penouta tailings were investigated and compared with the current leucogranite outcropping ores. The characterization was conducted through X-ray diffraction, scanning electron microscopy, and electron microprobe. In addition, automated mineralogy techniques were used to determine the mineral associations and liberation characteristics of ore minerals. The grade of the leucogranite outcropping was found to be about 80 ppm for Ta and 400 ppm for Sn, and in the tailings used for the liberation study, the concentrations of Ta and Sn were about 100 ppm Ta and 500 ppm Sn, respectively. In both, the leucogranite outcropping and tailings, the major minerals found were quartz, albite, K-feldspar, and white mica. Ore minerals identified were columbite-group minerals (CGM), microlite, and cassiterite. The majority of CGM examined were associated with cassiterite, quartz, and muscovite particle compositions and cassiterite was mainly associated with CGM, quartz, and muscovite. The liberation size was 180 µm for CGM.

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Morphology Control of the Nano-MnO2 by Microwave Hydrothermal Synthesis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.624.47 ◽

2012 ◽

Vol 624 ◽

pp. 47-50

Author(s):

Shi Lei Zhang ◽

Ben Niu ◽

Enlei Qi ◽

Lei Wang ◽

Jie Qiang Wang

Keyword(s):

Hydrothermal Synthesis ◽

Energy Dispersive Spectrometer ◽

Raw Material ◽

X Ray Diffraction ◽

Crystal Forms ◽

X Ray ◽

Microwave Assisted ◽

Structure And Morphology ◽

Microwave Hydrothermal ◽

Scanning Electron

In this paper, KMnO4 was used as raw material, nano-MnO2 with different morphologies such as flowers globular, hollow tubular and rodlike were obtained by the microwave assisted hydrothermal synthesis under the acidic condition. The crystal structure and morphology of the resultant MnO2 were characterized by X-ray Diffraction (XRD) and Scanning Electron Microscope (SEM), respectively. The elements and content of samples were tested by Energy Dispersive Spectrometer (EDS). The influence of reaction temperature and holding time on crystal forms and morphologies of the MnO2 was analyzed.

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Preparation and Properties of Ginger Essential Oil β-Cyclodextrin/Chitosan Inclusion Complexes

Coatings ◽

10.3390/coatings8090305 ◽

2018 ◽

Vol 8 (9) ◽

pp. 305 ◽

Cited By ~ 9

Author(s):

Yan Zhang ◽

Hui Zhang ◽

Fang Wang ◽

Li-Xia Wang

Keyword(s):

Particle Size ◽

Essential Oil ◽

Spray Drying ◽

Small Particle Size ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Ft Ir ◽

Thermal Stability Of ◽

Scanning Electron

The ginger essential oil/β-cyclodextrin (GEO/β-CD) composite, ginger essential oil/β-cyclodextrin/chitosan (GEO/β-CD/CTS) particles and ginger essential oil/β-cyclodextrin/chitosan (GEO/β-CD/CTS) microsphere were prepared with the methods of inclusion, ionic gelation and spray drying. Their properties were studied by using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermo-gravimetry analysis (TGA), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The results showed that the particle size of GEO/β-CD composite was smaller than that of β-CD and GEO/β-CD/CTS particles were loose and porous, while the microsphere obtained by spray drying had certain cohesiveness and small particle size. Besides, results also indicated that β-CD/CTS could modify properties and improve the thermal stability of GEO, which would improve its application value in food and medical industries.

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Extraction of Phosphorous from a Phosphorous-Containing Vanadium Titano-Magnetite Tailings by Direct Flotation

Processes ◽

10.3390/pr8070874 ◽

2020 ◽

Vol 8 (7) ◽

pp. 874 ◽

Cited By ~ 1

Author(s):

Junhui Xiao ◽

Chao Chen ◽

Wei Ding ◽

Yang Peng ◽

Tao Chen ◽

...

Keyword(s):

Electron Microscopy ◽

Paraffin Wax ◽

Low Grade ◽

X Ray Diffraction ◽

Flotation Process ◽

X Ray ◽

Pine Oil ◽

Flotation Concentration ◽

Scanning Electron

In this study, there is 1.42% P2O5 in the P-containing V-Ti magnetite tailings in Miyi Region of China, with the valuable minerals mainly including apatite, and aluminosilicate minerals as the main gangue components. The direction flotation process was used to recover phosphorous from the low-grade phosphorous-bearing V-Ti magnetite tailings. The results showed that an optimized phosphorous concentrate with a P2O5 grade of 31.35% and P2O5 recovery of 88.02% was obtained by flotation process of one roughing, three scavengings, and three cleanings under roughing conditions, which employed pulp pH of 9, grinding fineness of <0.039 mm occupying 90%, flotation concentration of 25%, and dosages of carboxymethylcellulose, oxidized paraffin wax soap, and pine oil of 400 g/t, 300 g/t, and 20 g/t, respectively. Optimized one scavenging, two scavenging, and three scavenging conditions used a pulp pH of 9, and dosages of carboxymethylcellulose, oxidized paraffin wax soap, and pine oil of 200 g/t, 150 g/t, 10 g/t; 100 g/t, 75 g/t, and 5 g/t; and 100 g/t, 75 g/t, and 5 g/t, respectively. Optimized one cleaning, two cleaning, and three cleaning condition dosages of carboxymethylcellulose of 100 g/t, 50 g/t, and 25 g/t, respectively. Study of analysis and characterization of phosphorous concentrate by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) show that most gangue minerals enter the flotation tailings, the main minerals in phosphorous concentrate are apatite, olivine, and feldspar.

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Composition and Microstructure of a Natural Nano-Structure Mineral: Six-Ring Rock

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.295-297.869 ◽

2011 ◽

Vol 295-297 ◽

pp. 869-872

Author(s):

Qing Shan Li ◽

Xin Wang ◽

Jun Liu ◽

Guang Zhong Xing

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Energy Dispersive Spectrometer ◽

The Body ◽

X Ray Diffraction ◽

Nano Structure ◽

X Ray ◽

Transmission Electron ◽

Nano Size ◽

Scanning Electron

Six-ring Rock is widely used as containers of water and additives to produce health care products. In this paper, the composition and microstructure of Six-ring Rock have been investigated by using scanning electron microscopy, energy dispersive spectrometer, transmission electron microscopy, x-ray diffraction and other technologies. Results show that Six-ring Rock is composed of CaMg(CO3)2, SiO2 and KAlSi3O8. Fe atoms exist in CaMg(CO3)2 by replacing Mg atoms. Six-ring Rock shows nano-size lamellar and acerose microstructures on the surface, and nano-size monocrystals in the body. Six-ring Rock is a natural nano structure mineral.

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The Degradation of Poly (Butylene Succinate)/Natural Rubber Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.934.110 ◽

2014 ◽

Vol 934 ◽

pp. 110-115

Author(s):

Li Gao ◽

Er Juan Zhi ◽

Ping Li Wang ◽

Jun Hui Ji

Keyword(s):

Green Composites ◽

X Ray Diffraction ◽

Rubber Composites ◽

Scanning Calorimetry ◽

Butylene Succinate ◽

X Ray ◽

Weight Losses ◽

Natural Rubber Composites ◽

Degradation Test ◽

Scanning Electron

In this study, poly (butylene succinate) (PBS)/nature rubber (NR) composites were prepared, and the effects of NR content on the biodegradability were evaluated by vermiculite-degradation test. X-ray Diffraction, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) were used to characterize the degraded blends. The weight losses of PBS/NR composites are higher than that of pure PBS, and increased with adding NR content. The weight loss of 30% NR content composite after 120 days is 16.84%. The XRD and DSC results show that the crystallinity of PBS/NR composites increase after buried in vermiculite. These results were confirmed using SEM observations by the presence of many large holes and more cracks in the degradation surface morphology of the increasing content of NR. It was observed that PBS/NR composites are green-composites or eco-materials.

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