Numerical simulation and application of micro-nano bubble releaser for irrigation

In oxygenated irrigation, there are problems of large oxygenated bubble particles, low oxygen concentration in water, and mismatch with current irrigation systems. In this paper, numerical simulation of micro-nano bubble releaser was carried out and the development of oxygenated irrigation equipment was studied. The release method of dissolved gas was selected to generate micro-nano bubbles after comparing different micro-nano bubble generation methods. The basic structure of the core-component releaser of generating micro-nano bubbles was initially determined. Effects of different structures of the release device on water aeration performance were studied by CFD analysis method. An optimal structure of the releaser was determined with orthogonal experiments based on a single factor experiment. The structural parameters included a throat of a 3 mm diameter, a 2 mm thick turbulent cavity, a six-degree exit angle, and two outlets. Optimal inlet and outlet pressure difference of the release device was 0.3 MPa. The bubble had an average particle size of 373.1 nm as measured. The release device was fabricated by 3D printing technology and the micro-nano bubble aeration irrigation device was developed. The system function test was carried out. Under the standard state, the performance parameters of the micro-nano bubble aerator included the maximum oxygen concentration of 11.4 mg/L, a total oxygen transfer coefficient of 0.4139 min-1, 0.0114 kg/h oxygenation capacity, and 60.81% oxygen utilization rate. The device had advantages of a high oxygen-increasing efficiency and a small volume, making it quite prospective in the field of oxygenated irrigation.

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Preparation of Magnesium-Based Cobalt-Ferrites (Co1−xMgxFe2O4) Nanoparticles by Sol–Gel Auto Combustion Method

International Journal of Nanoscience ◽

10.1142/s0219581x17600122 ◽

2017 ◽

Vol 17 (01n02) ◽

pp. 1760012

Author(s):

S. Gowreesan ◽

A. Ruban Kumar

Keyword(s):

Particle Size ◽

Structural Parameters ◽

Sol Gel ◽

Average Particle Size ◽

Combustion Method ◽

Dielectric Behavior ◽

Powder Xrd ◽

Average Particle ◽

Cobalt Ferrites ◽

Auto Combustion

The scope of the present work is in enhancing the particle size, and dielectric properties of Mg-substituted Cobalt ferrites nanoparticles prepared by sol–gel auto combustion method. The different ratios of Mg-substituted Co Ferrites (Co[Formula: see text]MgxFe2O4([Formula: see text], 0.05, 0.10, 0.15, 0.20 and 0.30)) are calcinated at 850[Formula: see text]C. The synthesized nanoparticles were characterized by powder XRD, FTIR, FE-SEM, EDX techniques and dielectric behavior. The structural parameters were confirmed from powder XRD and the average particle size is obtained from 39 to 67 nm due to the substitution of Mg[Formula: see text] which was calculated by Debye Scherrer’s formula. FE-SEM showed the surface morphology of the different ratio of the sample. The dielectric loss has measured the frequency range of 50[Formula: see text]Hz–5[Formula: see text]MHz. From electrical modulus, conductivity relaxation and thermal activation of charge carriers has been discussed.

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Phase Formation, Crystal Structure and Ion Conductivity of Silver Antimonate-Molybdates

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17872 ◽

2020 ◽

Vol 20 (7) ◽

pp. 4597-4600

Author(s):

Yu. A. Lupitskaya ◽

D. A. Kalganov ◽

L. Yu. Kovalenko ◽

F. A. Yaroshenko

Keyword(s):

Solid Phase ◽

Rietveld Method ◽

Structural Parameters ◽

Average Particle Size ◽

Structural Disorder ◽

Synthesis Temperature ◽

Average Particle ◽

Solid Phase Reaction ◽

Phase Reaction ◽

Pyrochlore Type

The features of the formation of compounds based on silver antimonate obtained in the AgNO3–Sb2O3–MoO3 system by the solid-phase reaction were investigated. For a synthesis temperature of 1023 K, a homogeneous concentration region of the Ag2−xSb2−xMoxO6 solid solution with a structure of the defective pyrochlore type in the range of 0.0 ≤ x ≤ 2.0 was detected. The Rietveld method, within the constraints of the Fd-3m space group, was used to refinement of X-ray diffraction data, specify the structural parameters of powders, and the correlation of structural disorder with their electrically conductive properties. Relative density and average particle size for ceramic samples sintered at 1223 K were determined using scanning electron microscopy.

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Enhanced Photocatlytic Activity of two Dimensional Graphitic C3N4@Co3O4 Core Shell Nanocomposite for Discriminatory Organic Transformation under Hg-Vapor Reactor

Material Science Research India ◽

10.13005/msri/180207 ◽

2021 ◽

Vol 18 (2) ◽

pp. 190-205

Author(s):

Anita Parashram Patil ◽

Satish Arvind Ahire ◽

Shubham Nand kishor Hiray

Keyword(s):

Electron Microscopy ◽

Cobalt Oxide ◽

Carbon Nitride ◽

Structural Parameters ◽

Average Particle Size ◽

Average Particle ◽

Co3o4 Nanoparticles ◽

Oxide Material ◽

Direct Heating ◽

Prepared Material

In the present investigation the material Co3O4 nanoparticles were prepared by co-precipitation method, while graphitic carbon nitride (g-C3N4) was prepared by direct heating of melamine. The nanocompositeg-C3N4- Co3O4were prepared by stoichiometric mixing and direct heating in porcelain boat followed by calcination. The prepared nanomaterials were characterized by various techniques. These both materials were characterized by XRD to get structural parameters and to confirm the average particle size of prepared nanomaterial. The scanning electron microscopy(SEM) was carried out to get surface characteristics of prepared materials. The energy dispersive spectroscopy was conducted to get elemental composition prepared material Co3O4and g-C3N4- Co3O4 .The transmission electron microscopy (TEM) was conducted to get lattice information of prepared material. While magnetic properties of both the material were investigated by means of vibrating sample magnetometer (VSM), since cobalt oxide is a ferromagnetic material. The surface area was confirmed from Brunauer-Emmett-Teller (BET) study. The g-C3N4- Co3O4nanocomposite has found enhanced surface areaof 78.48 m2/g in comparison to the sole Co3O4nanomaterial (55.23 m2/g). Both these prepared materials were utilized in photocatlytic degradation of CarbolFuchsin (CF) dye. The various parameters related to optimization of photocatlytic degradation of dyes were investigated in detail. The carbon nitride mediated cobalt oxide material is found to be very effective for degradation of CF dye and almost 97% of dye was successfully decomposed by the g-C3N4- Co3O4nanocomposite. The reusability test confirms that the prepared g-C3N4- Co3O4nanocomposite is very efficient in degradation of CF dye in multiple cycles with 110 minutes of contact time.

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The Influence of Milling Regimes in Beater Mill on Particle Size Distribution and Structural Characteristics of Strontium Hexaferrite Powder

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.284.158 ◽

2018 ◽

Vol 284 ◽

pp. 158-162

Author(s):

I.N. Yegorov ◽

Nikolay Ya. Egorov

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Fluidized Bed ◽

Structural Parameters ◽

Average Particle Size ◽

Strontium Hexaferrite ◽

Average Particle ◽

Electromagnetic Effect ◽

Coarse Material

The paper experimentally substantiates effectiveness of method of milling particulate ferromagnetic materials in magneto fluidized bed. Comparative results of particle size distributions and structural parameters of strontium hexaferrite SrFe12O19 powder obtained by milling coarse material in beater mill without electromagnetic effect and in same mill with formation of magneto fluidized bed from mill material are presented. The magneto fluidized bed is formed by constant and alternating gradient magnetic fields with induction lines that are mutually perpendicular and parallel to the plane of rotating beaters. It is shown that application of electromagnetic effect to milling coarse material in beater mill allowed to greatly intensify that process, significantly increase powder quality: increase particle size distribution uniformity and decrease average particle size from 1558.50 μm to 0.56 μm after 120 minutes of processing in the mill. X-ray diffraction analysis showed that milling in beater mill in magneto fluidized bed leads to reduction of coherent-scattering region size, increase of lattice microstrain and dislocation density, making powder more active during sintering process.

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Preparation and Characterization Silver Nanoparticle Embedded Polyamide Nanofiltration (NF) Membrane

MATEC Web of Conferences ◽

10.1051/matecconf/201815002003 ◽

2018 ◽

Vol 150 ◽

pp. 02003

Author(s):

Tengku Anisa Tengku Sallehudin ◽

Mazrul Nizam Abu Seman ◽

Syed Mohd Saufi Tuan Chik

Keyword(s):

Vitamin B12 ◽

Interfacial Polymerization ◽

Structural Parameters ◽

Average Particle Size ◽

Antimicrobial Properties ◽

Xrd Analysis ◽

Separation Performance ◽

Average Particle ◽

Face Centered Cubic ◽

Vis Spectroscopy

In this study, silver nanoparticles (AgNPs) were synthesized from tea leaves extract and its antimicrobial properties was tested on Escherichia coli (E. coli) using agar well method. The synthesized nanoparticles were characterized by using UV-vis spectroscopy, transmission electron microscopy (TEM) and X-ray diffraction (XRD). The result from XRD analysis shows that the synthesized AgNPs are a face-centered cubic (fcc) structure with an average particle size of 28±15 nm AgNPs which confirmed by TEM. The synthesized AgNPs were then used in the preparation of thin film composite NF membrane via interfacial polymerization method. Separation performance of the produced membrane was evaluated in term of membrane permeability and solute rejection (vitamin B12, NaCl and Na2SO4 solutions). Based on the structural parameters (pore size, rp and Δx/Ak) values obtained from vitamin B12 test, all membranes can be considered as tight NF membranes. From the salts rejection test, membranes with the addition of AgNPs exhibited higher salt rejection compared to the neat membranes.

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Properties of Nanosize Aluminum Nitride Powders Synthesized by Chemical Vapor Synthesis

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.434-435.830 ◽

2010 ◽

Vol 434-435 ◽

pp. 830-833

Author(s):

Jae Hwan Pee ◽

Jong Chul Park ◽

Kwang Taek Hwang ◽

Soo Ryong Kim ◽

Woo Seok Cho

Keyword(s):

Particle Size ◽

Reaction Temperature ◽

Average Particle Size ◽

Chemical Vapor ◽

Heating System ◽

Tube Furnace ◽

Average Particle ◽

Low Oxygen ◽

Chemical Vapor Synthesis ◽

Nano Size

AlN powders by the chemical vapor synthesis (CVS) process in the AlCl3-NH3-N2-H2 system were successfully synthesized. Gasified AlCl3 as a starting material was generated by pre-heating system and transported to the tube furnace in NH3-N2-H2 atmosphere. High crystalline AlN was synthesized at over 900°C. The average particle size of spherical AlN powders decreased from 250 to 40nm with increasing the reaction temperature of the tube furnace. Porous nano-size particles synthesized at high reaction temperature have low oxygen contents.

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Numerical simulation study on the influence of pulverized coal particle size on boiler combustion characteristics

E3S Web of Conferences ◽

10.1051/e3sconf/202021801009 ◽

2020 ◽

Vol 218 ◽

pp. 01009

Author(s):

Zhihai Cheng ◽

Yang Li ◽

Zhonghan Zhang

Keyword(s):

Numerical Simulation ◽

Particle Size ◽

Combustion Zone ◽

Coal Particle ◽

Average Particle Size ◽

Pulverized Coal ◽

Average Particle ◽

Temperature Level ◽

Nox Formation ◽

Average Temperature

The influence of pulverized coal particle size on combustion and NOx formation of 660MW tangential combustion ultra-supercritical boiler in a power plant was studied by using commercial software FLUENT. The average particle size of pulverized coal was set at 61μm, 71μm and 80μm, respectively. The results show that with the decrease of pulverized coal particle size, the overall temperature level of the boiler increases, the average temperature of the main combustion zone increases, the temperature of the upper part of the main combustion zone decreases, and the combustion of pulverized coal is more incomplete. However, the probability of particles sticking to the wall and the probability of coking and slagging of the boiler increases. The amount of NOx produced in the main combustion zone decreases, while the amount of NOx produced in the upper part of the main combustion zone increases, while the overall amount of NOx produced increases slightly.

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Preparation of PLGA Nanoparticles Encapsulated with Fluorescent Probe Coumarin-6

10.1101/614875 ◽

2019 ◽

Author(s):

Elizebeth Purr ◽

Jacob Marshall ◽

John Smith

Keyword(s):

Fluorescent Probe ◽

Encapsulation Efficiency ◽

Average Particle Size ◽

Double Emulsion ◽

Plga Nanoparticles ◽

Utilization Rate ◽

Average Particle ◽

Acid Copolymer ◽

Coumarin 6

AbstractIn this report, we provided a novel platform to prepare fluorescent probe coumarin-6 nanoparticles by using biodegradable material polylactic acid-glycolic acid copolymer (PLGA) as material. The coumarin-6-PLGA nanoparticles were prepared by double emulsion and solvent evaporation. The encapsulation efficiency and releasing kinetics were also investigated. Results indicate that the encapsulation efficiency of coumarin-6 nanoparticles was 51.6%, the utilization rate was 81.9%, the average particle size was 135 nm, and the leakage rate of coumarin-6 in vitro was lower than 72 h. 2%. Our experimental results provide evidence that PLGA nanoparticles can effectively encapsulate fluorescent probe Coumarin-6 and release the probe in a controlled manner.

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Enhanced catalytic activity of low-Pt content nanocatalysts supported on hollow carbon spheres for the ORR in alkaline media

MRS Advances ◽

10.1557/adv.2020.370 ◽

2020 ◽

Vol 5 (57-58) ◽

pp. 2961-2972

Author(s):

P.C. Meléndez-González ◽

E. Garza-Duran ◽

J.C. Martínez-Loyola ◽

P. Quintana-Owen ◽

I.L. Alonso-Lemus ◽

...

Keyword(s):

Catalytic Activity ◽

Anion Exchange ◽

Average Particle Size ◽

Synthesis Method ◽

Alkaline Media ◽

High Catalytic Activity ◽

Average Particle ◽

Carbon Spheres ◽

Hollow Carbon ◽

Hollow Carbon Spheres

In this work, low-Pt content nanocatalysts (≈ 5 wt. %) supported on Hollow Carbon Spheres (HCS) were synthesized by two routes: i) colloidal conventional polyol, and ii) surfactant-free Bromide Anion Exchange (BAE). The nanocatalysts were labelled as Pt/HCS-P and Pt/HCS-B for polyol and BAE, respectively. The physicochemical characterization of the nanocatalysts showed that by following both methods, a good control of chemical composition was achieved, obtaining in addition well dispersed nanoparticles of less than 3 nm TEM average particle size (d) on the HCS. Pt/HCS-B contained more Pt0 species than Pt/HCS-P, an effect of the synthesis method. In addition, the structure of the HCS remains more ordered after BAE synthesis, compared to polyol. Regarding the catalytic activity for the Oxygen Reduction Reaction (ORR) in 0.5 M KOH, Pt/HCS-P and Pt/HCS-B showed a similar performance in terms of current density (j) at 0.9 V vs. RHE than the benchmark commercial 20 wt. % Pt/C. However, Pt/HCS-P and Pt/HCS-B demonstrated a 6 and 5-fold increase in mass catalytic activity compared to Pt/C, respectively. A positive effect of the high specific surface area of the HCS and its interactions with metal nanoparticles and electrolyte, which promoted the mass transfer, increased the performance of Pt/HCS-P and Pt/HCS-B. The high catalytic activity showed by Pt/HCS-B and Pt/HCS-P for the ORR, even with a low-Pt content, make them promising cathode nanocatalysts for Anion Exchange Membrane Fuel Cells (AEMFC).

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A New Method for Direct Determination of the Recoilless Fraction with Application to Magnetic Nanoparticles

MRS Proceedings ◽

10.1557/proc-721-e3.7 ◽

2002 ◽

Vol 721 ◽

Author(s):

Monica Sorescu

Keyword(s):

Room Temperature ◽

Average Particle Size ◽

Direct Determination ◽

Average Particle ◽

Lattice Method ◽

Recoilless Fraction ◽

Single Room ◽

Magnetite Particles ◽

Physical Mixtures

AbstractWe propose a two-lattice method for direct determination of the recoilless fraction using a single room-temperature transmission Mössbauer measurement. The method is first demonstrated for the case of iron and metallic glass two-foil system and is next generalized for the case of physical mixtures of two powders. We further apply this method to determine the recoilless fraction of hematite and magnetite particles. Finally, we provide direct measurement of the recoilless fraction in nanohematite and nanomagnetite with an average particle size of 19 nm.

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