Synthesis, Property and Mechanism Analysis of a Novel Polyhydroxy Organic Amine Shale Hydration Inhibitor

Based on the adsorption mechanism analysis of polyhydroxy organic compound on a shale surface, a novel polyhydroxy organic amine shale hydration inhibitor N, N, N′, N′-tetrakis (2-hydroxyethyl) ethylenediamine (THEED) was synthesized via a nucleophilic reaction by using diethanolamine and dibromoethane as raw materials. Its structure was characterized by Fourier transform infrared spectrometry (FTIR), Hydrogen Nuclear Magnetic Resonance (1H NMR) and Liquid Chromatography Mass Spectrometry (LCMS). The inhibition performance of THEED was studied by a shale rolling recovery experiment, a linear expansion experiment and the particle size distribution experiment. Results showed the shale rolling recovery rate in 2.0 wt % THEED solutions was up to 89.6% at the rolling condition of 100 °C × 16 h, and the linear expansion height of artificial shale core in 2.0 wt % THEED solutions was just 4.74 mm after 16 h. The average particle size of Na-bentonite (Na-MMT) in fresh water was 8.05 μm, and it was observed that the average particle size has been increased to 124 μm in 2.0 wt % THEED solutions. The shale hydration inhibition mechanism of the novel inhibitor THEED was analyzed by FTIR, Scanning Electron Microscopy (SEM) and X-ray diffractometry (XRD), we concluded that the nice shale hydration inhibition performance of THEED was achieved by means of intercalation and adsorption onto the surface of shale. The superior shale hydration inhibition property makes THEED promising in maintaining wellbore stability in drilling engineering.

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Mechanism Analysis of FTIR Absorption Characteristic of MgO Nano-Powder

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.158.145 ◽

2010 ◽

Vol 158 ◽

pp. 145-158 ◽

Cited By ~ 3

Author(s):

Guo Liang Liu ◽

Yi Min Zhu ◽

Zhi Jun Ma ◽

Xin Fang

Keyword(s):

Particle Size ◽

Infrared Absorption ◽

Average Particle Size ◽

Absorption Characteristic ◽

Average Particle ◽

Ir Absorption ◽

Dimensional Chain ◽

Mechanism Analysis ◽

Nano Powder ◽

Vibration Model

Nano-MgO powders with different size form 30 to 100 nm are prepared and measured by XRD and IR. FTIR results show that nano-MgO powder has abnormal infrared absorption behaviors compared with that of micron scale; and there exist blue shifts of infrared absorption peaks with the decrease of the particles size. But when the average particle size of nano-MgO powder is down to less than 50 nm, there are red shifts of infrared absorption peaks. The aim of the paper is to analyze the mechanism of IR absorption characteristic of MgO Nano-powder by a single- dimensional chain vibration model.

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New thermal deblocking characterisation method of aqueous blocked polyurethane

Pigment & Resin Technology ◽

10.1108/prt-08-2013-0074 ◽

2014 ◽

Vol 43 (4) ◽

pp. 194-200 ◽

Cited By ~ 8

Author(s):

Yanhua Zhang ◽

Jun Cao ◽

Haiyan Tan ◽

Jiyou Gu

Keyword(s):

Particle Size ◽

Average Particle Size ◽

Wood Adhesive ◽

Infrared Spectrometry ◽

Particle Analysis ◽

Average Particle ◽

Content Type ◽

Wood Processing ◽

Blocking Rate ◽

Blocked Isocyanate

Purpose – The mechanisms of the deblocking reaction of the polyurethane with blocking agent were investigated in detail relatively using thermogravimetric analysis (TGA), Fourier transform infrared spectrometry (FTIR) and X-ray photoelectron spectroscopy (XPS). This kind of method for polyurethane as the application of wood adhesives can provide the conditions of application and the main theoretical basis. Design/methodology/approach – The blocking rate and latex particle size distribution were determined using the titrimetric analysis and the laser particle analysis, respectively. TGA, FTIR, XPS and differential scanning calorimetry were used to investigate the deblocking temperature and time of the blocked isocyanate in detail. Findings – The results indicated that the blocking rate was approximately 97 per cent and the average particle size was 360 nm. The results of laser particle analysis have confirmed that the dispersivity of the blocked polyurethane emulsion was good. XPS results showed that the amount of –O = C-N-benzyl groups increased with an increasing deblocking temperature and subsequently reached equilibrium. In summary, the blocked isocyanate was deblocked at temperatures ranging from 50 to 90°C. Research limitations/implications – An important approach in future wood adhesive work would be to gain access to man-made board application data. Practical implications – The paper provided some useful information about deblocking mechanisms of blocked polyurethane that would be helpful to guide applied practical applications as wood adhesive. Social implications – To promote China’s wood processing technology progress and solve the problem of shortage of the natural quality of wood is of important practical significance. Originality/value – The paper is the first to use the XPS characterisation method to characterise deblocking polyurethane solution.

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Effect of diisocyanates on the structure and properties of UV-curable polyurethane dispersions with nano-scale particles

e-Polymers ◽

10.1515/epoly.2008.8.1.1926 ◽

2008 ◽

Vol 8 (1) ◽

Author(s):

Yanyan Wei ◽

Haobo Xin

Keyword(s):

Particle Size ◽

Average Particle Size ◽

Molecular Structures ◽

Hexamethylene Diisocyanate ◽

Infrared Spectrometry ◽

Average Particle ◽

Mass Ratio ◽

Uv Curable ◽

Nano Scale ◽

Polyurethane Dispersions

AbstractA series of anionic polyurethane prepolymers with different molecular structures were synthesized. Different amounts of hexamethylene diisocyanate (HDI) and toluence diisocyanate (TDI) were employed in the synthesis. When the carboxylic content was 0.3 mmol/g, the colloidal stability of the polyurethane dispersions was rather good and their particle size was nano-scale. Moreover, no acetone or other solvent were used during the process of emulsification. The structures of the polyurethane prepolymers were characterized by Fourier transform Infrared spectrometry with attenuated total reflectance (FTIR-ATR) and Gel permeation chromatography (GPC). It was found that the mass ratio of HDI to TDI was able to be quantitatively analyzed by means of FTIR-ATR. The molecular weight and distribution did not show a regular trend with the changing of HDI/TDI ratio. The influence of diisocyanate on the particle size and the coating properties was investigated. It seems that hexamethylene diisocyanate was helpful for obtaining nano-scale particles. These polyurethane dispersions could obtain an average particle size less than 100 nm when mass ratio of HDI/TDI was above 0.25. The polyurethane dispersions with nano-scale particle had a transparent appearance with a bluish cast. It is indicated that the hydrophilic efficiency would be improved and the coating hardness decreased if more HDI was employed.

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Determination of grinding parameters of fenugreek seed

Journal of Spices and Aromatic Crops ◽

10.25081/josac.2017.v26.i1.802 ◽

1970 ◽

Vol 26 (1) ◽

pp. 16 ◽

Cited By ~ 3

Author(s):

S Balasubramanian ◽

Rajkumar Rajkumar ◽

K K Singh

Keyword(s):

Particle Size ◽

Energy Consumption ◽

Moisture Content ◽

Specific Energy ◽

Feed Rate ◽

Average Particle Size ◽

Specific Energy Consumption ◽

Average Particle ◽

Fenugreek Seeds ◽

Fenugreek Seed

Experiment to identify ambient grinding conditions and energy consumed was conducted for fenugreek. Fenugreek seeds at three moisture content (5.1%, 11.5% and 17.3%, d.b.) were ground using a micro pulverizer hammer mill with different grinding screen openings (0.5, 1.0 and 1.5 mm) and feed rate (8, 16 and 24 kg h-1) at 3000 rpm. Physical properties of fenugreek seeds were also determined. Specific energy consumptions were found to decrease from 204.67 to 23.09 kJ kg-1 for increasing levels of feed rate and grinder screen openings. On the other hand specific energy consumption increased with increasing moisture content. The highest specific energy consumption was recorded for 17.3% moisture content and 8 kg h-1 feed rate with 0.5 mm screen opening. Average particle size decreased from 1.06 to 0.39 mm with increase of moisture content and grinder screen opening. It has been observed that the average particle size was minimum at 0.5 mm screen opening and 8 kg h-1 feed rate at lower moisture content. Bond’s work index and Kick’s constant were found to increase from 8.97 to 950.92 kWh kg-1 and 0.932 to 78.851 kWh kg-1 with the increase of moisture content, feed rate and grinder screen opening, respectively. Size reduction ratio and grinding effectiveness of fenugreek seed were found to decrease from 4.11 to 1.61 and 0.0118 to 0.0018 with the increase of moisture content, feed rate and grinder screen opening, respectively. The loose and compact bulk densities varied from 219.2 to 719.4 kg m-3 and 137.3 to 736.2 kg m-3, respectively.

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Formulating SLN and NLC as Innovative Drug Delivery Systems for Non-Invasive Routes of Drug Administration

Current Medicinal Chemistry ◽

10.2174/0929867326666190624155938 ◽

2020 ◽

Vol 27 (22) ◽

pp. 3623-3656 ◽

Cited By ~ 1

Author(s):

Bruno Fonseca-Santos ◽

Patrícia Bento Silva ◽

Roberta Balansin Rigon ◽

Mariana Rillo Sato ◽

Marlus Chorilli

Keyword(s):

Drug Delivery ◽

Particle Size ◽

Drug Release ◽

Drug Loading ◽

Average Particle Size ◽

Delivery Systems ◽

Average Particle ◽

Minor Importance ◽

Routes Of Administration ◽

Non Invasive

Colloidal carriers diverge depending on their composition, ability to incorporate drugs and applicability, but the common feature is the small average particle size. Among the carriers with the potential nanostructured drug delivery application there are SLN and NLC. These nanostructured systems consist of complex lipids and highly purified mixtures of glycerides having varying particle size. Also, these systems have shown physical stability, protection capacity of unstable drugs, release control ability, excellent tolerability, possibility of vectorization, and no reported production problems related to large-scale. Several production procedures can be applied to achieve high association efficiency between the bioactive and the carrier, depending on the physicochemical properties of both, as well as on the production procedure applied. The whole set of unique advantages such as enhanced drug loading capacity, prevention of drug expulsion, leads to more flexibility for modulation of drug release and makes Lipid-based nanocarriers (LNCs) versatile delivery system for various routes of administration. The route of administration has a significant impact on the therapeutic outcome of a drug. Thus, the non-invasive routes, which were of minor importance as parts of drug delivery in the past, have assumed added importance drugs, proteins, peptides and biopharmaceuticals drug delivery and these include nasal, buccal, vaginal and transdermal routes. The objective of this paper is to present the state of the art concerning the application of the lipid nanocarriers designated for non-invasive routes of administration. In this manner, this review presents an innovative technological platform to develop nanostructured delivery systems with great versatility of application in non-invasive routes of administration and targeting drug release.

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Azithromycin nanosuspension preparation using evaporative precipitation into aqueous solution (EPAS) method and its comparative dissolution study

Current Pharmaceutical Analysis ◽

10.2174/1573412917999200909145745 ◽

2020 ◽

Vol 17 ◽

Author(s):

Mohammad Hossain Shariare ◽

Tonmoy Kumar Mondal ◽

Hani Alothaid ◽

Md. Didaruzzaman Sohel ◽

MD Wadud ◽

...

Keyword(s):

Aqueous Solution ◽

Particle Size ◽

Dissolution Rate ◽

Average Particle Size ◽

Scale Up ◽

Average Particle ◽

Total Drug ◽

Residual Solvent ◽

Dissolution Study ◽

Drug Content

Aim: EPAS (evaporative precipitation into aqueous solution) was used in the current studies to prepare azithromycin nanosuspensions and investigate the physicochemical characteristics for the nanosuspension batches with the aim of enhancing the dissolution rate of the nanopreparation to improve bioavailability. Methods: EPAS method used in this study for preparing azithromycin nanosuspension was achieved through developing an in-house instrumentation method. Particle size distribution was measured using Zetasizer Nano S without sample dilution. Dissolved azithromycin nanosuspensions were also compared with raw azithromycin powder and commercially available products. Total drug content of nanosuspension batches were measured using an Ultra-Performance Liquid Chromatography (UPLC) system with Photodiode Array (PDA) detector while residual solvent was measured using gas chromatography (GC). Results: The average particle size of azithromycin nanosuspension was 447.2 nm and total drug content was measured to be 97.81% upon recovery. Dissolution study data showed significant increase in dissolution rate for nanosuspension batch when compared to raw azithromycin and commercial version (microsuspension). The residual solvent found for azithromycin nanosuspension is 0.000098023 mg/ mL or 98.023 ppb. Conclusion: EPAS was successfully used to prepare azithromycin nanoparticles that exhibited significantly enhanced dissolution rate. Further studies are required to scale up the process and determine long term stability of the nanoparticles.

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Evaluation of the Effects of Filler Fineness on the Properties of an Epoxy Asphalt Mixture

Materials ◽

10.3390/ma14082003 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2003

Author(s):

Wei Xu ◽

Jintao Wei ◽

Zhengxiong Chen ◽

Feng Wang ◽

Jian Zhao

Keyword(s):

Particle Size ◽

Average Particle Size ◽

Asphalt Mixture ◽

Average Particle ◽

Fine Dust ◽

Bonding Structure ◽

Epoxy Asphalt ◽

Mineral Powder ◽

Marshall Stability ◽

Mixture Sample

The type and fineness of a filler significantly affect the performance of an asphalt mixture. There is a lack of specific research on the effects of filler fineness and dust from aggregates on the properties of epoxy asphalt (EA) mixtures. The effects of aggregate dust and mineral powder on the properties of an EA mixture were evaluated. These filler were tested to determine their fineness, specific surface area and mineral composition. The effects of these fillers on the EA mastic sample and mixture were evaluated. The morphology of the EA mastic samples was analyzed using scanning electron microscopy (SEM). The effects of the fillers on the Marshall stability, tensile strength and fatigue performance of the EA mixture were evaluated. The dust from the aggregates exhibited an even particle size distribution, and its average particle size was approximately 20% of that of the mineral powder. The SEM microanalysis showed that the EA mastic sample containing relatively fine dust formed a tight and dense interfacial bonding structure with the aggregate. The EA mixture sample containing filler composed of dust from aggregate had a significantly higher strength and longer fatigue life than that of the EA sample containing filler composed of mineral powder.

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Surface Activity of Humic Acid and Its Sub-Fractions from Forest Soil

Sustainability ◽

10.3390/su13158122 ◽

2021 ◽

Vol 13 (15) ◽

pp. 8122

Author(s):

Shijie Tian ◽

Weiqiang Tan ◽

Xinyuan Wang ◽

Tingting Li ◽

Fanhao Song ◽

...

Keyword(s):

Surface Tension ◽

Particle Size ◽

Humic Acid ◽

Forest Soil ◽

Surface Activity ◽

Self Assembly ◽

Average Particle Size ◽

Gaussian Model ◽

Exponential Model ◽

Average Particle

Surface activity of humic acid (HA) and its six sub-fractions isolated from forest soil were characterized by surface tension measurements, dynamic light scattering, and laser doppler electrophoresis. The surface tension of HA and its sub-fractions reduced from 72.4 mN·m−1 to 36.8 mN·m−1 in exponential model with the increasing concentration from 0 to 2000 mg·L−1. The critical micelle concentration (CMC) and Z-average particle size ranged from 216–1024 mg·L−1 and 108.2–186.9 nm for HA and its sub-fractions, respectively. The CMC have related with alkyl C, O-alkyl C, aromatic C, and carbonyl C (p < 0.05), respectively, and could be predicted with the multiple linear regression equation of CMC, CMC = 18896 − 6.9 × C-296 × alkyl C-331 × aromatic C-17019 × H/C + 4054 × HB/HI (p < 0.05). The maximum particle size was 5000 nm after filtered by a membrane with pore size of 450 nm, indicating HA and its sub-fractions could progressed self-assembly at pH 6.86. The aggregate sizes of number-base particle size distributions were mainly in six clusters including 2 ± 1 nm, 5 ± 2 nm, 10 ± 3 nm, 21 ± 8 nm, 40 ± 10 nm, and >50 nm analyzed by Gaussian model that maybe due to the inconsistency of the components and structures of the HA sub-fractions, requiring further study. It is significance to explore the surface activity of HA and its sub-fractions, which is helpful to clarify the environmental behavior of HA.

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Microstructure Characterization of Ag Nanoparticles Prepared by Hydrothermal Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.1138 ◽

2012 ◽

Vol 476-478 ◽

pp. 1138-1141

Author(s):

Zhi Qiang Wei ◽

Qiang Wei ◽

Li Gang Liu ◽

Hua Yang ◽

Xiao Juan Wu

Keyword(s):

Crystal Structure ◽

Particle Size ◽

Hydrothermal Method ◽

Ag Nanoparticles ◽

Average Particle Size ◽

Average Particle ◽

Face Centered Cubic ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Face Centered

Ag nanoparticles were successfully synthesized by hydrothermal method under the polyol system combined with traces of sodium chloride, Silver nitrate(AgNO3) and polyvinylpyrrolidone (PVP) acted as the silver source and dispersant respectively. The samples by this process were characterized via X-ray powder diffraction (XRD), Brunauer–Emmett–Teller (BET) adsorption equation, transmission electron microscopy (TEM) and the corresponding selected area electron diffraction (SAED) to determine the chemical composition, particle size, crystal structure and morphology. The experiment results indicate that the crystal structure of the samples is face centered cubic (FCC) structure as same as the bulk materials, The specific surface area is 24 m2/g, the particle size distribution ranging from10 to 50 nm, with an average particle size about 26 nm obtained by TEM and confirmed by XRD and BET results.

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Wheat Grinding Process with Low Moisture Content: A New Approach for Wholemeal Flour Production

Processes ◽

10.3390/pr9010032 ◽

2020 ◽

Vol 9 (1) ◽

pp. 32

Author(s):

Waleed H. Hassoon ◽

Dariusz Dziki ◽

Antoni Miś ◽

Beata Biernacka

Keyword(s):

Particle Size ◽

Moisture Content ◽

Average Particle Size ◽

Average Particle ◽

Grinding Process ◽

Mixing Properties ◽

New Approach ◽

Grain Moisture ◽

Flour Production ◽

And Storage

The objective of this study was to determine the grinding characteristics of wheat with a low moisture content. Two kinds of wheat—soft spelt wheat and hard Khorasan wheat—were dried at 45 °C to reduce the moisture content from 12% to 5% (wet basis). Air drying at 45 °C and storage in a climatic chamber (45 °C, 10% relative humidity) were the methods used for grain dehydration. The grinding process was carried out using a knife mill. After grinding, the particle size distribution, average particle size and grinding energy indices were determined. In addition, the dough mixing properties of wholemeal flour dough were studied using a farinograph. It was observed that decreasing the moisture content in wheat grains from 12% to 5% made the grinding process more effective. As a result, the average particle size of the ground material was decreased. This effect was found in both soft and hard wheat. Importantly, lowering the grain moisture led to about a twofold decrease in the required grinding energy. Moreover, the flour obtained from the dried grains showed higher water absorption and higher dough stability during mixing. However, the method of grain dehydration had little or no effect on the results of the grinding process or dough properties.

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