scholarly journals Effects of Hydrothermal and Microwave Dual Treatment and Zein on the Enzymolysis of High Amylose Corn Starch

Gels ◽  
2022 ◽  
Vol 8 (1) ◽  
pp. 29
Author(s):  
Jie Liu ◽  
Qiuye Yang ◽  
Tiantian Yuan ◽  
Yawei Liu ◽  
Guihong Fang
Keyword(s):  
Moisture Content ◽  
Corn Starch ◽  
Average Particle Size ◽  
Microwave Treatment ◽  
Decomposition Temperature ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
High Amylose

Resistant starch (RS) type 2-high-amylose corn starch (HACS) was subjected to simultaneous hydrothermal (25% moisture content, 90 °C for 12 h) and microwave (35% moisture content, 40 W/g microwaving for 4 min) treatment and zein (at a zein to treated starch ratio of 1:5, 50 °C for 1 h) to improve its resistance to enzymolysis. Scanning electron microscopy (SEM) highlighted the aggregation and adhesion of the composite. The average particle size of the composite (27.65 μm) was exceeded that of both the HACS (12.52 μm) and the hydrothermal and microwave treated HACS (hydro-micro-HACS) (12.68 μm). The X-ray diffraction results revealed that the hydro-micro-HACS and composite remained B-type, while their crystallinity significantly decreased to 16.98% and 12.11%, respectively. The viscosity of the hydro-micro-HACS and composite at 50 °C was 25.41% and 35.36% lower than that of HACS. The differential scanning calorimetry (DSC) results demonstrated that the composite displayed a new endothermic peak at 95.79 °C, while the weight loss rate and decomposition temperature were 7.61% and 2.39% lower than HACS, respectively. The RS content in HACS, the hydro-micro-HACS, and composite was 47.12%, 57.28%, and 62.74%, respectively. In conclusion, hydrothermal and microwave treatment combined with zein provide an efficient physical strategy to enhance the RS type 2-HACS.

A Calcination Technology for Ultrafine La3NbO7 Powder Prepared by Sol-Gel Process

2011 ◽  
Vol 412 ◽  
pp. 271-274
Author(s):  
Ying Li ◽  
Qiang Xu ◽  
Ling Dai
Keyword(s):  
Single Phase ◽  
Sol Gel ◽  
Average Particle Size ◽  
Complex Method ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Acid Complex ◽  
Calcination Process ◽  
Sol Gel Process

In order to prepare ultrafine La3NbO7 powder, a potential material for thermal barrier coatings, the calcination process of La3NbO7 was studied in this paper.The precursor of La3NbO7 was synthesized by using a citric acid complex method. A calcination process had been systematically investigated. The reaction temperature was determined by differential scanning calorimetry (DSC). The phase composition of powders was characterized by X-ray diffraction (XRD), and the morphology was obtained by scanning electron microscope (SEM). The results revealed that the single-phase La3NbO7 powder could be successfully prepared while the calcination temperature exceeded 800°C and a better morphology could be maintained at 800°C for 4 hours. Considering all above, an optimum calcination scheme was adopted at 800°C for 4 hours. The as-prepared La3NbO7 powders had a grain size of about 50nm and an average particle size of about 300nm.

scholarly journals PCL/PHBV Microparticles as Innovative Carriers for Oral Controlled Release of Manidipine Dihydrochloride

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Fernanda Malaquias Barboza ◽  
Willian Moreira Machado ◽  
Luiz Renato Olchanheski Junior ◽  
Josiane Padilha de Paula ◽  
Sônia Faria Zawadzki ◽  
...  
Keyword(s):  
Controlled Release ◽  
Animal Studies ◽  
Average Particle Size ◽  
Spherical Shape ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Chemically Modified ◽  
Diffraction Patterns

Microparticles of poly(ε-caprolactone) (PCL) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) containing manidipine dihydrochloride (MAN) were successfully prepared by the simple emulsion/solvent evaporation method. All formulations showed loading efficiency rates greater than 80% and average particle size less than 8 μm. Formulations had spherical shape with smooth and porous surface for PCL and PHBV, respectively. According to Fourier-transform infrared spectroscopy, initial components were not chemically modified during microencapsulation. X-ray diffraction patterns and differential scanning calorimetry demonstrated that this process led to drug amorphization.In vitrodissolution studies showed that all microparticles prolonged MAN release, mainly which one obtained using PCL that contained 5% of drug loaded (PCL-M5). Animal studies demonstrated that formulationPCL-M5was able to keep the variation of mean arterial pressure after phenylephrine administration up to 24 hours. These data confirmed the sustained antihypertensive effect of the investigated microparticles. Results provided an experimental basis for using formulationPCL-M5as a feasible carrier for oral controlled release of MAN intended for treating high blood pressure.

Sol–gel-based chemical synthesis of NdFeB hard magnetic nanoparticles

2018 ◽  
Vol 32 (34n36) ◽  
pp. 1840070 ◽  
Author(s):  
Jinshan Zhang ◽  
Wei Wu ◽  
Fangshi Meng ◽  
Hao Ding ◽  
Jiling Dong
Keyword(s):  
Saturation Magnetization ◽  
Sol Gel ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Oxide Powders ◽  
Intermediate Phases ◽  
Washing Process ◽  
Oxide Phases

NdFeB nanoparticles were synthesized by a sol–gel method. Firstly, NdFeB gel was prepared by using citric acid and glycol as the gel, and the corresponding salts of Nd, Fe and boric acid. The gel was subsequently annealed under a high temperature condition to obtain NdFeB-oxide phases. Then NdFeB nanoparticles were yielded by reductive annealing of precursors. Microstructure, phase composition and magnetic properties were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and vibrating sample magnetometer (VSM), and also differential scanning calorimetry (DSC) analysis was performed to determine the annealing temperature. At 400[Formula: see text]C, intermediate phases of Fe3BO5 and NdBO3 were formed and stable up to 600[Formula: see text]C; while at 800[Formula: see text]C, they would reacted in presence of oxygen to form NdFeO3 and B2O3. Nd2O3 and Fe2O3 were also formed at this temperature. SEM micrographs of reduced powders after washing process showed an average particle size below 100 nm in all the samples. VSM results showed the oxide powder formed at 800[Formula: see text]C had a coercivity of 1.55 kOe and a saturation magnetization of 1.08 emu/g. The powder synthesized by reduction of oxide powders at 800[Formula: see text]C had a coercivity of 1.02 kOe and a saturation magnetization of 14.17 emu/g.

scholarly journals pH Induced Fabrication of Kaolinite-Chitosan Biocomposite

2016 ◽  
Vol 68 ◽  
pp. 1-9 ◽  
Author(s):  
Shaikat Chandra Dey ◽  
Mohammad Al-Amin ◽  
Taslim Ur Rashid ◽  
Md Ashaduzzaman ◽  
Sayed Md Shamsuddin
Keyword(s):  
Environmental Science ◽  
Average Particle Size ◽  
Chitosan Solution ◽  
Aqueous System ◽  
Vital Role ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Morphological Studies ◽  
Functionalized Materials

Functionalization of indigenous materials improves inherent physicochemical properties that depend mainly on their fabrication techniques. Here, pH triggered biocomposites using different proportions of kaolinite and chitosan were fabricated. It was revealed that the biocomposites were formed in 1M acetic acid and stabilized after dropwise addition of the mixture of kaolinite and chitosan solution in 3M NaOH. Binding of kaolinite and chitosan at their interface through functional groups was studied using Fourier transform infrared (FT-IR) spectroscopy and dynamic light scattering (DLS). The average particle size of the biocomposite in aqueous system having 80% w/w kaolinite and 20% w/w chitosan was determined to be 400.8 nm. Crystallinity disappearance of chitosan in the biocomposite, as shown in x-ray diffraction (XRD) spectrum, supports the wrapping of kaolinite with soft and flexible chitosan. Differential scanning calorimetry (DSC) showed the thermal stability of the biocomposites and it was found that the biocomposite fabricated from 50% w/w kaolinite and 50% w/w chitosan was stabled up to 318°C. Morphological studies were carried out using scanning electron microscopy (SEM), where a progressive tendency towards granular morphology was evidenced with increase in kaolinite content. These functionalized materials in bionanocomposite structure would play a vital role in advanced research in analytical and environmental science.

Role of gadolinium(III) complex in improving thermal stability of polythiophene composite

2015 ◽  
Vol 69 (10) ◽  
Author(s):  
Ferooze Ahmad Rafiqi ◽  
Kowsar Majid
Keyword(s):  
Thermal Stability ◽  
Thermal Analysis ◽  
Average Particle Size ◽  
Degree Of Crystallinity ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Thermal Stability Of

AbstractThis paper involves the preparation of polythiophene (PTP) and its composite by the oxidative polymerisation method by using ferric chloride as an oxidant and thiophene monomer. The gadolinium( III) complex obtained by the refluxing technique was used as dopant in the PTP matrix. On the basis of the spectroscopic characterisation, seven-coordinate geometry is proposed for the complex. Conductance measurement confirms the non-selectrolyte nature of complex. The PTP and its composite were subjected to FTIR, X-ray diffraction and scanning electron microscope techniques. The powder X-ray diffraction pattern showed the high crystalline nature of the complex which in turn developed a good degree of crystallinity in the PTP composite. The average particle size was calculated as 4.655 ˚A and 3.737 ˚A for the dopant and PTP composite, respectively, by using Debye Scherrer’s equation. Thermal analysis was performed by thermogravimetric (TG) analysis, differential thermal analysis (DTA) and differential scanning calorimetry (DSC) techniques. The TG, DTA and DSC results were well-correlated. The thermal analysis revealed the high thermal stability of the dopant which in turn improved the thermal stability of the PTP composite, revealing the potential of the composite for high temperature applications.

Determination of grinding parameters of fenugreek seed

1970 ◽  
Vol 26 (1) ◽  
pp. 16 ◽  
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.  

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

Processes ◽  
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.

scholarly journals Synthesis and Characterization of N-Substituted Polyether-Block-Amide Copolymers

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 773
Author(s):  
Jyun-Yan Ye ◽  
Kuo-Fu Peng ◽  
Yu-Ning Zhang ◽  
Szu-Yuan Huang ◽  
Mong Liang
Keyword(s):  
Titanium Isopropoxide ◽  
Decomposition Temperature ◽  
Phenyl Isocyanate ◽  
Cross Linking ◽  
Resonance Spectroscopy ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Degradation Temperature ◽  
Melt Polycondensation ◽  
Structural Regularity

A series of N-substituted polyether-block-amide (PEBA-X%) copolymers were prepared by melt polycondensation of nylon-6 prepolymer and polytetramethylene ether glycol at an elevated temperature using titanium isopropoxide as a catalyst. The structure, thermal properties, and crystallinity of PEBA-X% were investigated using nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, wide angle X-ray diffraction, and thermogravimetric analysis. In general, the crystallinity, melting point, and thermal degradation temperature of PEBA-X% decreased as the incorporation of N-methyl functionalized groups increased, owing to the disruption caused to the structural regularity of the copolymer. However, in N-acetyl functionalized analogues, the crystallinity first dropped and then increased because of a new γ form arrangement that developed in the microstructure. After the cross-linking reaction of the N-methyl-substituted derivative, which has electron-donating characteristics, with poly(4,4′-methylenebis(phenyl isocyanate), the decomposition temperature of the resulting polymer significantly increased, whereas no such improvements could be observed in the case of the electro-withdrawing N-acetyl-substituted derivative, because of the incompleteness of its cross-linking reaction.

scholarly journals Thermal, Structural, and Physical Properties of Freeze Dried Tropical Fruit Powder

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
K. A. Athmaselvi ◽  
C. Kumar ◽  
M. Balasubramanian ◽  
Ishita Roy
Keyword(s):  
Particle Size ◽  
Physical Properties ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Tropical Fruit ◽  
X Ray ◽  
Freeze Dried ◽  
Fruit Powder ◽  
Lcr Meter

This study evaluates the physical properties of freeze dried tropical (guava, sapota, and papaya) fruit powders. Thermal stability and weight loss were evaluated using TGA-DSC and IR, which showed pectin as the main solid constituent. LCR meter measured electrical conductivity, dielectric constant, and dielectric loss factor. Functional groups assessed by FTIR showed presence of chlorides, and O–H and N–H bonds in guava, chloride and C–H bond in papaya, and chlorides, and C=O and C–H bonds in sapota. Particle size and type of starch were evaluated by X-ray diffraction and microstructure through scanning electronic microscopy. A semicrystalline profile and average particle size of the fruit powders were evidenced by X-ray diffraction and lamellar/spherical morphologies by SEM. Presence of A-type starch was observed in all three fruits. Dependence of electric and dielectric properties on frequency and temperature was observed.

scholarly journals Synthesis of MgO Nanoparticles by Solvent Mixed Spray Pyrolysis Technique for Optical Investigation

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
K. R. Nemade ◽  
S. A. Waghuley
Keyword(s):  
Particle Size ◽  
Spray Pyrolysis ◽  
Spray Pyrolysis Technique ◽  
Average Particle Size ◽  
Band Gap Energy ◽  
Average Particle ◽  
Optical Investigation ◽  
X Ray Diffraction ◽  
Mgo Nanoparticles ◽  
Electron Microscope Analysis

Solvent mixed spray pyrolysis technique has attracted a global interest in the synthesis of nanomaterials since reactions can be run in liquid state without further heating. Magnesium oxide (MgO) is a category of the practical semiconductor metal oxides, which is extensively used as catalyst and optical material. In the present study, MgO nanoparticles were successfully synthesized using a solvent mixed spray pyrolysis. The X-ray diffraction pattern confirmed the formation of MgO phase with an excellent crystalline structure. Debye-Scherrer equation is used for the determination of particle size, which was found to be 9.2 nm. Tunneling electron microscope analysis indicated that the as-synthesized particles are nanoparticles with an average particle size of 9 nm. Meanwhile, the ultraviolet-visible spectroscopy of the resulting product was evaluated to study its optical property via measurement of the band gap energy value.

Sign in / Sign up

Export Citation Format

Share Document