scholarly journals Effects of Bamboo Shoot Dietary Fiber on Mechanical Properties, Moisture Distribution, and Microstructure of Frozen Dough

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Hua Zhang ◽  
Yanyan Zhang ◽  
Xintian Wang ◽  
Qisen Xiang ◽  
Yanhong Bai ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Dietary Fiber ◽  
Bound Water ◽  
Free Water ◽  
Moisture Distribution ◽  
Dependent Manner ◽  
Bamboo Shoot ◽  
Scanning Calorimetry ◽  
Frozen Dough ◽  
Addition Amount

In this paper, the effects of Bamboo shoot dietary fiber (BSDF) on the mechanical properties, moisture distribution, and microstructure of frozen dough were investigated. The state and distribution of water in frozen dough was determined by differential scanning calorimetry (DSC) and low-field nuclear magnetic resonance (LNMR) spectroscopy. The microstructure of frozen dough was studied. The structure of the gluten protein network found in wheat flour dough was studied by scanning electron microscopy (SEM). The result showed that the BSDF could significantly improve the viscoelasticity and extensibility of frozen dough after thawing in a dose-dependent manner. It was significantly improved with the increase in the addition amount of BSDF (P<0.05). DSC analysis showed that the freezable water content and thermal stability of frozen dough were increased after the addition of BSDF. LNMR analysis showed that the appropriate (<0.1%) addition amount of BSDF could significantly (P<0.05) decline the contents of bound water. Meanwhile, the loose bound water and free water were raised significantly (P<0.05) after the addition of BSDF. Moreover, the addition of BSDF induces arrangement of starch granule and gluten network in frozen dough. BSDF can be used as a novel quality improver of frozen dough.

Preparation and Properties of a Water-Swelling Rubber by in situ Formed Lithium Acrylate in Nitrile Rubber

2005 ◽  
Vol 13 (2) ◽  
pp. 181-190 ◽  
Author(s):  
Wentan Ren ◽  
Zonglin Peng ◽  
Yong Zhang ◽  
Yinxi Zhang
Keyword(s):  
Mechanical Properties ◽  
Bound Water ◽  
Free Water ◽  
High Water ◽  
Nitrile Rubber ◽  
Molar Ratio ◽  
Scanning Calorimetry ◽  
Swelling Properties ◽  
Water Swelling

Lithium acrylate (LiAA) was in situ prepared in nitrile rubber (NBR) through neutralization of lithium hydroxide (LiOH) and acrylic acid (AA) during mixing. The NBR/LiAA compounds were vulcanized with dicumyl peroxide (DCP). The in situ preparation and polymerization of LiAA were characterized using Fourier transform infrared (FTIR) spectrometer. The micrographs of the compounds and vulcanizates were explored using a scanning electron microscope (SEM). The effects of DCP and LiAA contents on the water-swelling and mechanical properties of the vulcanizates were studied. The relationship between the LiOH/AA molar ratio and the properties of the vulcanizates was investigated. The results showed that the in situ formed LiAA could improve the mechanical properties and water–swelling properties of the NBR/LiAA vulcanizates. The vulcanizates properly compounded had high water-swelling ratio over 800% and tensile strength more than 12MPa. The differential scanning calorimetry (DSC) measurements indicated that the water absorbed in the vulcanizate existed in PLiAA and NBR networks in three different physical states, namely, free water, freezable bound water and non-freezable bound water.

Determine the Moisture Distribution in Sewage Sludge by Drying Differential

2014 ◽  
Vol 665 ◽  
pp. 404-407 ◽  
Author(s):  
Wan Yu ◽  
Pei Sheng Li
Keyword(s):  
Sewage Sludge ◽  
Interstitial Water ◽  
Bound Water ◽  
Free Water ◽  
High Accuracy ◽  
Moisture Distribution ◽  
Municipal Sewage ◽  
Municipal Sewage Sludge ◽  
Hot Air ◽  
Critical Water Content

Moisture distribution in sewage sludge was considered as the essential of thermal drying. Some methods were given in literatures to test the moisture distribution, but there was no standard method to determine the critical water content between different kinds of water. The municipal sewage sludge was dried by hot air in this work. Based on the drying curve, the derivative of drying rate with respect to dry basis moisture content was brought out to analyze the moisture distribution in sewage sludge. Results show that this method can easily determine the free water, interstitial water, surface water and bound water with a high accuracy. The present work can provide new insight to determine the moisture distribution in sewage sludge, which was still lacking in the literatures.

scholarly journals Measurement and Modelling of Moisture Distribution and Water Binding Energy of Dredged Sludge

Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3395
Author(s):  
Feiyan Mao ◽  
Yingjie Zhao ◽  
Yiping Zhang ◽  
Zhou Chen ◽  
Lu Yin
Keyword(s):  
Binding Energy ◽  
Water Distribution ◽  
Bound Water ◽  
Free Water ◽  
Moisture Distribution ◽  
Water Binding ◽  
Dredged Sludge ◽  
Urban Watercourse ◽  
Experimental Values ◽  
Stage 1

The dewatering of dredged sludge is a critical step in the minimization and reutilization of this solid waste. However, there is a lack of available literature on the fundamental drying characteristics of dredged sludge. In this work, two kinds of typical sludge dredged from an urban watercourse were tested by low-field NMR to investigate the water distribution in sludge and it was found that water contained in sludge can be classified into three categories: free water, capillary water and bound water. In addition, a novel model was proposed based on the Lennard-Jones equation and Kelvin law to quantitatively evaluate the binding energy during drying. Further, the model results were experimentally verified by thermogravimetry differential thermal analysis (TG-DTA). Results show that the trends of the model are consistent with the experimental values and the gradient of energy consumption during dehydration can be divided into three main stages. In stage 1, the total energy required for dewatering equals the latent heat of free water. In stage 2, binding energy reaches dozens to hundreds of kJ/kg accounting for capillary action. In stage 3, binding energy increases steeply reaching almost thousands of kJ/kg due to intermolecular interactions. All the discovered aspects could improve the management and disposal of dredged sludge from an energy cost perspective.

Study on the Moisture Distribution within the Wood Treated with Microwave

2011 ◽  
Vol 327 ◽  
pp. 105-108 ◽  
Author(s):  
Jian Fang Yu ◽  
Ji Long Guo ◽  
Jing Ya Nan ◽  
Bing Hu Sun
Keyword(s):  
Relaxation Time ◽  
Bound Water ◽  
Free Water ◽  
Microwave Treatment ◽  
Moisture Distribution ◽  
Microwave Drying ◽  
Water Molecules ◽  
Saturation Point ◽  
Initial Stage ◽  
Before And After

In this paper, Siberian elm (Ulmus pumila L) which was regarded as our research object was measured with the technology of Nuclear Magnetic Resonance (NMR) before and after being treated with microwave at different periods of time. By comparing the spin - spin relaxation time of hydrogen nuclear (T2) which can reflect the mobility of water molecules, the states and changes of the moisture distribution within the wood in the process of microwave treatment have been analyzed. The results indicate that in the initial stage of drying, the degree of the decline in bound water is greater than that in free water, for there may be a process of the transformation from bound water to free water; With the drying going on, the movement and expulsion mainly happen to free water above the fiber saturation point (FSP); In the later stage of drying, when the moisture content decreases near the FSP, bound water has also begun moving significantly on the expulsion of plenty of free water. In the final stage of drying, the decrease of hydrogen bonds in water molecules resulting from a plentiful reduction in free water, as well as the increased permeability within the wood caused by the microwave drying makes the relaxation time of free water to rise up.

scholarly journals Machine Learning for the Identification of Hydration Mechanisms of Pharmaceutical-Grade Cellulose Polymers and Their Mixtures with Model Drugs

2021 ◽  
Vol 11 (16) ◽  
pp. 7751
Author(s):  
Przemysław Talik ◽  
Aleksander Mendyk
Keyword(s):  
Bound Water ◽  
Free Water ◽  
Optimal Number ◽  
Ice Melting ◽  
Scanning Calorimetry ◽  
Multiple Components ◽  
Hypothetical Mechanism ◽  
The Individual ◽  
Matrix Free ◽  
Dsc Curves

Differently bound water molecules confined in hydrated hydroxypropyl cellulose (HPC) type MF and their mixtures (1:1 w/w) with lowly soluble salicylic acid and highly soluble sodium salicylate were investigated by differential scanning calorimetry (DSC). The obtained ice-melting DSC curves of the HPC/H2O samples were deconvoluted into multiple components, using a specially developed curve decomposition tool. The ice-melting enthalpies of the individual deconvoluted components were used to estimate the amounts of water in three states in the HPC matrix: free water (FW), freezing bound water (FBW), and non-freezing water (NFW). A search for an optimal number of Gaussian functions was carried out among all available samples of data and was based on the analysis of the minimum fitting error vs. the number of Gaussians. Finally, three Gaussians accounting for three fractions of water were chosen for further analysis. The results of the calculations are discussed in detail and compared to previously obtained experimental DSC data. AI/ML tools assisted in theory elaboration and indirect validation of the hypothetical mechanism of the interaction of water with the HPC polymer.

scholarly journals Effect of bamboo shoot dietary fiber on gel properties, microstructure and water distribution of pork meat batters

2020 ◽  
Vol 33 (7) ◽  
pp. 1180-1190
Author(s):  
Ke Li ◽  
Jun-Ya Liu ◽  
Lei Fu ◽  
Ying-Ying Zhao ◽  
He Zhu ◽  
...  
Keyword(s):  
Rheological Properties ◽  
Dietary Fiber ◽  
Water Distribution ◽  
Meat Products ◽  
Free Water ◽  
Pork Meat ◽  
Bamboo Shoot ◽  
Gel Properties ◽  
Meat Batters ◽  
Water Holding

Objective: To develop healthier comminuted meat products to meet consumer demand, the gel properties, rheological properties, microstructure and water distribution of pork meat batters formulated with various amounts of bamboo shoot dietary fiber (BSDF) were investigated.Methods: Different levels of BSDF (0% to 4%) were added to pork batters, and the pH, color, water-holding capacity, texture and rheological properties of pork batters were determined. Then, pork batters were analyzed for their microstructure and water distribution using scanning electron microscopy (SEM) and low-field nuclear magnetic resonance (LF-NMR).Results: Compared with the control, BSDF addition into meat batters showed a significant reduction in L*-value and a significant increase in b*-value (p<0.05). BSDF addition of up to 4% reduced the pH value of pork batters by approximately 0.15 units; however, the cooking loss and expressible water loss decreased significantly (p<0.05) with the increased addition of BSDF. The hardness and gel strength were noticeably enhanced (p<0.05) as the content of BSDF increased. The rheological results showed that BSDF added into pork batters produced higher storage modulus (G′) and loss modulus (G″) values. The SEM images suggested that the addition of BSDF could promote pork batters to form a more uniform and compact microstructure. The proportion of immobilized water increased significantly (p<0.05), while the population of free water was decreased (p<0.05), indicating that BSDF improved the water-holding capability of pork batters by decreasing the fraction of free water.Conclusion: BSDF could improve the gel properties, rheological properties and water distribution of pork meat batters and decrease the proportion of free water, suggesting that BSDF has great potential as an effective binder in comminuted meat products.

scholarly journals Temperature- and pH-sensitive hydrogels of sequential Ti-containing interpenetrating polymer networks

2021 ◽  
pp. 42-49
Author(s):  
Т.Т. Аlekseeva ◽  
◽  
N.V. Iarova ◽  
Keyword(s):  
Molecular Weight ◽  
Water Content ◽  
Average Molecular Weight ◽  
Polymer Networks ◽  
Bound Water ◽  
Free Water ◽  
Interpenetrating Polymer Networks ◽  
Hydroxyethyl Methacrylate ◽  
Scanning Calorimetry ◽  
Polymer Component

Hydrogels of sequential Ti-containing interpenetrating polymer networks based on hydrophilic cross-linked polyurethanes with different molecular weight of polyethylene glycols and Ti-containing copolymer were synthesized based on 2-hydroxyethyl methacrylate and titanium isopropoxide. The composition of sequential interpenetrating polymer networks was determined by the degree of equilibrium swelling of the polyurethane networks in 2-hydroxyethyl methacrylate and Ti-containing comonomer. It was established that the content of the second component of the interpenetrating polymer networks increases with increasing the average molecular weight value of the polyurethane network. It was shown that the obtained highly sensitive hydrogels of Ti-containing interpenetrating polymer networks react to the changes in the temperature and pH. These factors significantly change the equilibrium water content in the hydrogels. Differential scanning calorimetry allowed determining the phase transitions that are characteristic of bound and free water, which is a part of the hydrogel of polyurethanes, interpenetrating polymer networks and Ti-containing interpenetrating polymer networks. The results showed that the content of bound water and the degree of its binding to the components of the interpenetrating polymer networks depend on the chemical structure of the network, the nature of a second polymer component (which is a part of the interpenetrating polymer networks), the polarity and hydrophilicity of macromolecules, and the size of hydrogel cells. Regardless of the nature of the second polymer component, there is a general trend for all interpenetrating polymer networks: the total water content increases with increasing the average molecular weight of the polyurethane matrix networks.

scholarly journals Influence of Konjac Glucomannan and Frozen Storage on Rheological and Tensile Properties of Frozen Dough

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 794 ◽  
Author(s):  
Tingting Cui ◽  
Rui Liu ◽  
Tao Wu ◽  
Wenjie Sui ◽  
Min Zhang
Keyword(s):  
Tensile Properties ◽  
Binding Capacity ◽  
Frozen Storage ◽  
Free Water ◽  
Konjac Glucomannan ◽  
Scanning Calorimetry ◽  
Water Binding ◽  
Gluten Proteins ◽  
Frozen Dough ◽  
The Impact

The impact of various amounts of konjac glucomannan on the structural and physicochemical properties of gluten proteins/dough at different periods of frozen storage is evaluated in the present study. As frozen storage time was prolonged, the molecular weight and the free sulfhydryl content of gluten proteins and the tensile properties of frozen dough all decreased. The addition of konjac glucomannan reduced the variations in the structural and rheological properties of gluten proteins/dough. Frozen dough with 2.5% added konjac glucomannan showed the highest water binding capacity and retarded the migration of water. Scanning electron microscopy and differential scanning calorimetry results also revealed that adding konjac glucomannan reduced the cracks and holes in the dough and enhanced its thermal stability. The correlations between mechanical characteristics and structure parameters further indicated that konjac glucomannan could not only stabilize the structures of gluten proteins but also bind free water to form more stable complexes, thereby retaining the rheological and tensile properties of the frozen dough.

scholarly journals Optimization of Collagen Chemical Crosslinking to Restore Biocompatibility of Tissue-Engineered Scaffolds

Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 832
Author(s):  
Mohammad Mirazul Islam ◽  
Dina B. AbuSamra ◽  
Alexandru Chivu ◽  
Pablo Argüeso ◽  
Claes H. Dohlman ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Crosslinking Agent ◽  
Collagen Scaffold ◽  
Human Monocyte ◽  
Subsequent Treatment ◽  
Sodium Metabisulfite ◽  
Corneal Tissue ◽  
Dependent Manner ◽  
Collagen Scaffolds ◽  
Enzymatic Stability

Collagen scaffolds, one of the most used biomaterials in corneal tissue engineering, are frequently crosslinked to improve mechanical properties, enzyme tolerance, and thermal stability. Crosslinkers such as 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) are compatible with tissues but provide low crosslinking density and reduced mechanical properties. Conversely, crosslinkers such as glutaraldehyde (GTA) can generate mechanically more robust scaffolds; however, they can also induce greater toxicity. Herein, we evaluated the effectivity of double-crosslinking with both EDC and GTA together with the capability of sodium metabisulfite (SM) and sodium borohydride (SB) to neutralize the toxicity and restore biocompatibility after crosslinking. The EDC-crosslinked collagen scaffolds were treated with different concentrations of GTA. To neutralize the free unreacted aldehyde groups, scaffolds were treated with SM or SB. The chemistry involved in these reactions together with the mechanical and functional properties of the collagen scaffolds was evaluated. The viability of the cells grown on the scaffolds was studied using different corneal cell types. The effect of each type of scaffold treatment on human monocyte differentiation was evaluated. One-way ANOVA was used for statistical analysis. The addition of GTA as a double-crosslinking agent significantly improved the mechanical properties and enzymatic stability of the EDC crosslinked collagen scaffold. GTA decreased cell biocompatibility but this effect was reversed by treatment with SB or SM. These agents did not affect the mechanical properties, enzymatic stability, or transparency of the double-crosslinked scaffold. Contact of monocytes with the different scaffolds did not trigger their differentiation into activated macrophages. Our results demonstrate that GTA improves the mechanical properties of EDC crosslinked scaffolds in a dose-dependent manner, and that subsequent treatment with SB or SM partially restores biocompatibility. This novel manufacturing approach would facilitate the translation of collagen-based artificial corneas to the clinical setting.

scholarly journals Relationship between the Stereocomplex Crystallization Behavior and Mechanical Properties of PLLA/PDLA Blends

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1851
Author(s):  
Hye-Seon Park ◽  
Chang-Kook Hong
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Crystallization Behavior ◽  
Mechanical Analysis ◽  
X Ray Diffraction ◽  
Nucleation Agent ◽  
Scanning Calorimetry ◽  
Nucleation Sites ◽  
Wide Range ◽  
Degree Of Crystallization

Poly (l-lactic acid) (PLLA) is a promising biomedical polymer material with a wide range of applications. The diverse enantiomeric forms of PLLA provide great opportunities for thermal and mechanical enhancement through stereocomplex formation. The addition of poly (d-lactic acid) (PDLA) as a nucleation agent and the formation of stereocomplex crystallization (SC) have been proven to be an effective method to improve the crystallization and mechanical properties of the PLLA. In this study, PLLA was blended with different amounts of PDLA through a melt blending process and their properties were calculated. The effect of the PDLA on the crystallization behavior, thermal, and mechanical properties of PLLA were investigated systematically by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), polarized optical microscopy (POM), dynamic mechanical analysis (DMA), and tensile test. Based on our findings, SC formed easily when PDLA content was increased, and acts as nucleation sites. Both SC and homo crystals (HC) were observed in the PLLA/PDLA blends. As the content of PDLA increased, the degree of crystallization increased, and the mechanical strength also increased.

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