scholarly journals Calculation of the Boundary Dimensions of Functionally Active Nanoparticles

2020 ◽  
Vol 5 (1) ◽  
pp. 1-9
Author(s):  
Zulayho A. Smanova ◽  
Tokhir Kh. Rakhimov ◽  
Muxtarjan Mukhamediev ◽  
Dilfuza Gafurova ◽  
Dilbar Shaxidova
Keyword(s):  
Particle Size ◽  
Chemical Composition ◽  
Boundary Conditions ◽  
Present Article ◽  
Size Dependence ◽  
Specific Property ◽  
Equal Size ◽  
Direct Measurements ◽  
Active Nanoparticles

Size is a key characteristic of nanoparticles that determines whether the objects belong to this category. Currently, there are not enough experiments on materials of the same chemical composition but of different dispersion in particle size, with equal size of the particles or grains of each sample of material investigated. In the present article, the authors show that the effect of the dispersion of the particle size determines whether the size dependence of a specific property can be calculated alternatively to the direct measurements. By finding the correlations between nano-properties and content of nanoparticles' fractions of different sizes, the boundary conditions can be calculated.

Perlite particle size and NO3-/NH4+ ratio affect growth and chemical composition of purple coneflower (Echinacea purpurea L.) in hydroponics

2021 ◽  
Vol 162 ◽  
pp. 113285
Author(s):  
Fatemeh Ahmadi ◽  
Abbas Samadi ◽  
Ebrahim Sepehr ◽  
Amir Rahimi ◽  
Sergey Shabala
Keyword(s):  
Particle Size ◽  
Chemical Composition ◽  
Echinacea Purpurea ◽  
Purple Coneflower

scholarly journals Influencing Factors of the Mineral Carbonation Process of Iron Ore Mining Waste in Sequestering Atmospheric Carbon Dioxide

2021 ◽  
Vol 13 (4) ◽  
pp. 1866
Author(s):  
Noor Allesya Alis Ramli ◽  
Faradiella Mohd Kusin ◽  
Verma Loretta M. Molahid
Keyword(s):  
Carbon Dioxide ◽  
Particle Size ◽  
Chemical Composition ◽  
Iron Ore ◽  
Divalent Cations ◽  
Mining Industry ◽  
Mining Waste ◽  
Aluminum Silicate ◽  
Mineral Carbonation ◽  
Carbonation Process

Mining waste may contain potential minerals that can act as essential feedstock for long-term carbon sequestration through a mineral carbonation process. This study attempts to identify the mineralogical and chemical composition of iron ore mining waste alongside the effects of particle size, temperature, and pH on carbonation efficiency. The samples were found to be alkaline in nature (pH of 6.9–7.5) and contained small-sized particles of clay and silt, thus indicating their suitability for mineral carbonation reactions. Samples were composed of important silicate minerals needed for the formation of carbonates such as wollastonite, anorthite, diopside, perovskite, johannsenite, and magnesium aluminum silicate, and the Fe-bearing mineral magnetite. The presence of Fe2O3 (39.6–62.9%) and CaO (7.2–15.2%) indicated the potential of the waste to sequester carbon dioxide because these oxides are important divalent cations for mineral carbonation. The use of small-sized mine-waste particles enables the enhancement of carbonation efficiency, i.e., particles of <38 µm showed a greater extent of Fe and Ca carbonation efficiency (between 1.6–6.7%) compared to particles of <63 µm (0.9–5.7%) and 75 µm (0.7–6.0%). Increasing the reaction temperature from 80 °C to 150–200 °C resulted in a higher Fe and Ca carbonation efficiency of some samples between 0.9–5.8% and 0.8–4.0%, respectively. The effect of increasing the pH from 8–12 was notably observed in Fe carbonation efficiency of between 0.7–5.9% (pH 12) compared to 0.6–3.3% (pH 8). Ca carbonation efficiency was moderately observed (0.7–5.5%) as with the increasing pH between 8–10. Therefore, it has been evidenced that mineralogical and chemical composition were of great importance for the mineral carbonation process, and that the effects of particle size, pH, and temperature of iron mining waste were influential in determining carbonation efficiency. Findings would be beneficial for sustaining the mining industry while taking into account the issue of waste production in tackling the global carbon emission concerns.

scholarly journals Variation of the Chemical Composition of Waste Cooking Oils upon Bentonite Filtration

Resources ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 108 ◽  
Author(s):  
Alberto Mannu ◽  
Gina Vlahopoulou ◽  
Paolo Urgeghe ◽  
Monica Ferro ◽  
Alessandra Del Caro ◽  
...  
Keyword(s):  
Particle Size ◽  
Chemical Composition ◽  
Solid Phase ◽  
Volatile Fraction ◽  
X Ray Diffraction ◽  
Specific Chemical ◽  
Waste Cooking Oils ◽  
Main Components ◽  
Cooking Oils ◽  
Chemical Groups

The chemical composition and the color of samples of waste cooking oils (WCOs) were determined prior to and after filtration on two different pads of bentonite differing in particle size. The volatile fraction was monitored by headspace solid-phase microextraction (HS-SPME) coupled with gas-chromatography, while the variation of the composition of the main components was analyzed by 1H NMR. Both techniques allowed the detection of some decomposition products, such as polymers, terpenes, and derivatives of the Maillard process. The analysis of the chemical composition prior to and after bentonite treatment revealed a tendency for the clays to retain specific chemical groups (such as carboxylic acids or double bonds), independent of their particle size. A pair comparison test was conducted in order to detect the sensory differences of the intensity of aroma between the WCO treated with the two different bentonites. In addition, characterization of the bentonite by means of powder X-ray diffraction (XRD) and thermogravimetric measurements (TG) was performed.

Optical studies on II–VI semiconductor quantum dots: Particle size dependence of the high pressure phase stability

1996 ◽  
Vol 203 ◽  
pp. 217-224 ◽  
Author(s):  
John Schroeder ◽  
Lih-Wen Hwang ◽  
Markus R. Silvestri ◽  
Mierie Lee ◽  
Peter D. Persans
Keyword(s):  
Quantum Dots ◽  
Particle Size ◽  
High Pressure ◽  
Phase Stability ◽  
Size Dependence ◽  
Semiconductor Quantum Dots ◽  
High Pressure Phase ◽  
Optical Studies ◽  
Pressure Phase

Cosmogenic 7Be: Particle size distribution and chemical composition of 7Be-carrying aerosols in the atmosphere in Japan

2021 ◽  
Vol 237 ◽  
pp. 106690
Author(s):  
Yukinori Narazaki ◽  
Akihiro Sakoda ◽  
Syunta Takahashi ◽  
Noriyuki Momoshima
Keyword(s):  
Particle Size ◽  
Chemical Composition ◽  
Particle Size Distribution ◽  
Size Distribution

scholarly journals Influence of Brazilian pine seed flour addition on rheological, chemical and sensory properties of gluten-free rice flour cakes

2018 ◽  
Vol 48 (6) ◽  
Author(s):  
Mônica Ikeda ◽  
Carlos Wanderlei Piler Carvalho ◽  
Cristiane Vieira Helm ◽  
Henriette Monteiro Cordeiro de Azeredo ◽  
Rossana Catie Bueno de Gogoy ◽  
...  
Keyword(s):  
Particle Size ◽  
Chemical Composition ◽  
Experimental Design ◽  
Rice Flour ◽  
Gluten Free ◽  
Araucaria Angustifolia ◽  
Sensory Acceptance ◽  
Seed Flour ◽  
Flour Sample ◽  
Paste Viscosity

ABSTRACT: Brazilian pine seeds (pinhão) are gluten-free seeds produced by the native pine species named Araucaria angustifolia. In this study, gluten-free cake mixes composed of Brazilian pine seed flour and rice flour were developed. The cake mixes were produced following a Simplex Centroid experimental design, with rice flour and Brazilian pine seed flour contents ranging from 50 to 100% and from 0 to 50%, respectively. Mixes were analyzed for chemical composition, apparent paste viscosity, and particle size distribution. The resulting cakes were analyzed for sensory acceptance, texture, specific volume and chemical composition. The Brazilian pine seed flour showed a peak viscosity on heating of 1.761Pa.s against 4.747Pa.s for the 100% rice flour sample. The variation of firmness of cakes decreased with increasing percentage of Brazilian pine seed flour. Cakes containing Brazilian pine seed flour at 25-37.5% of the formulation presented highest overall acceptance.

Sign in / Sign up

Export Citation Format

Share Document