scholarly journals Functional Properties of Two-Component Hydrogel Systems Based on Gelatin and Polyvinyl Alcohol—Experimental Studies Supported by Computational Analysis

2021 ◽  
Vol 22 (18) ◽  
pp. 9909
Author(s):  
Karolina Labus ◽  
Lukasz Radosinski ◽  
Piotr Kotowski
Keyword(s):  
Polyvinyl Alcohol ◽  
Functional Properties ◽  
Experimental Studies ◽  
Hydrolytic Degradation ◽  
Absorption Capacity ◽  
Modeling Analysis ◽  
Hydrogel Matrix ◽  
Industrial Use ◽  
Opposite Tendency ◽  
Insight Into

The presented research is focused on an investigation of the effect of the addition of polyvinyl alcohol (PVA) to a gelatin-based hydrogel on the functional properties of the resulting material. The main purpose was to experimentally determine and compare the properties of hydrogels differing from the content of PVA in the blend. Subsequently, the utility of these matrices for the production of an immobilized invertase preparation with improved operational stability was examined. We also propose a useful computational tool to predict the properties of the final material depending on the proportions of both components in order to design the feature range of the hydrogel blend desired for a strictly specified immobilization system (of enzyme/carrier type). Based on experimental research, it was found that an increase in the PVA content in gelatin hydrogels contributes to obtaining materials with a visibly higher packaging density, degree of swelling, and water absorption capacity. In the case of hydrolytic degradation and compressive strength, the opposite tendency was observed. The functionality studies of gelatin and gelatin/PVA hydrogels for enzyme immobilization indicate the very promising potential of invertase entrapped in a gelatin/PVA hydrogel matrix as a stable biocatalyst for industrial use. The molecular modeling analysis performed in this work provides qualitative information about the tendencies of the macroscopic parameters observed with the increase in the PVA and insight into the chemical nature of these dependencies.

Proximal and Functional Properties of Edible Ripened Split Beans of Coastal Wild Legume Canavalia maritima

2019 ◽  
Vol 15 (3) ◽  
pp. 228-233
Author(s):  
Prabhavathi Supriya ◽  
Kandikere R. Sridhar
Keyword(s):  
Water Absorption ◽  
Functional Properties ◽  
Crude Protein ◽  
Functional Foods ◽  
Protein Solubility ◽  
Calorific Value ◽  
Absorption Capacity ◽  
Total Lipids ◽  
Crude Fibre ◽  
Protein Rich

Background: Utilization of wild legumes has received prime importance in the recent past to compensate the scarcity of protein-rich foods as well as to tackle the protein energy malnutrition. Ripened split beans of Canavalia maritima devoid of seed coat and testa serve as traditional nutraceutical source for the coastal dwellers of Southwest India. Objective: The present study projects proximal and functional attributes of uncooked and cooked ripened split beans of C. maritima to be used in the preparation of functional foods. Methods: Proximal properties (moisture, crude protein, total lipids, crude fibre, carbohydrates and calorific value) and functional properties (protein solubility, gelation capacity, water-absorption, oilabsorption, emulsion qualities and foam qualities) of split beans were evaluated by standard methods. Results: Cooking did not significantly changed the crude protein, total lipids, ash, carbohydrates and calorific value, while it significantly increased the crude fibre. The protein solubility, water-absorption capacity, foam capacity and foam stability were significantly higher in uncooked than cooked beans. The cooked beans were superior to uncooked beans in least gelation concentration, low oil-absorption capacity, emulsion activity and emulsion stability. Conclusion: The functional properties of split bean flours were influenced by the proximal components like crude protein, total lipids and crude fibre. The energy-rich ripened split beans of C. maritima can serve as a new potential source for production of value added functional foods owing to their rich protein, rich carbohydrates, low-lipid and potential bioactive attributes.

scholarly journals Highly absorbent hydrogels comprised from interpenetrated networks of alginate–polyurethane for biomedical applications

2021 ◽  
Vol 32 (6) ◽  
Author(s):  
Jesús A. Claudio-Rizo ◽  
Nallely Escobedo-Estrada ◽  
Sara L. Carrillo-Cortes ◽  
Denis A. Cabrera-Munguía ◽  
Tirso E. Flores-Guía ◽  
...  
Keyword(s):  
Biomedical Applications ◽  
Degradation Rate ◽  
High Capacity ◽  
Hydrolytic Degradation ◽  
Absorption Capacity ◽  
Amide Bonds ◽  
E Coli ◽  
Swelling Capacity ◽  
And Storage ◽  
Potential Area

AbstractDeveloping new approaches to improve the swelling, degradation rate, and mechanical properties of alginate hydrogels without compromising their biocompatibility for biomedical applications represents a potential area of research. In this work, the generation of interpenetrated networks (IPN) comprised from alginate–polyurethane in an aqueous medium is proposed to design hydrogels with tailored properties for biomedical applications. Aqueous polyurethane (PU) dispersions can crosslink and interpenetrate alginate chains, forming amide bonds that allow the structure and water absorption capacity of these novel hydrogels to be regulated. In this sense, this work focuses on studying the relation of the PU concentration on the properties of these hydrogels. The results indicate that the crosslinking of the alginate with PU generates IPN hydrogels with a crystalline structure characterized by a homogeneous smooth surface with high capacity to absorb water, tailoring the degradation rate, thermal decomposition, and storage module, not altering the native biocompatibility of alginate, providing character to inhibit the growth of E. coli and increasing also its hemocompatibility. The IPN hydrogels that include 20 wt.% of PU exhibit a reticulation index of 46 ± 4%, swelling capacity of 545 ± 13% at 7 days of incubation at physiological pH, resistance to both acidic and neutral hydrolytic degradation, mechanical improvement of 91 ± 1%, and no cytotoxicity for monocytes and fibroblasts growing for up to 72 h of incubation. These results indicate that these novel hydrogels can be used for successful biomedical applications in the design of wound healing dressings.

scholarly journals Shedding light on the nature of the catalytically active species in photocatalytic reactions using Bi2O3 semiconductor

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Paola Riente ◽  
Mauro Fianchini ◽  
Patricia Llanes ◽  
Miquel A. Pericàs ◽  
Timothy Noël
Keyword(s):  
Experimental Studies ◽  
Heterogeneous Photocatalysis ◽  
Active Species ◽  
Organic Transformations ◽  
Alkyl Bromides ◽  
Catalytically Active ◽  
Visible Light Driven ◽  
Photocatalytic Reactions ◽  
Insight Into ◽  
Photocatalytic Processes

AbstractThe importance of discovering the true catalytically active species involved in photocatalytic systems allows for a better and more general understanding of photocatalytic processes, which eventually may help to improve their efficiency. Bi2O3 has been used as a heterogeneous photocatalyst and is able to catalyze several synthetically important visible-light-driven organic transformations. However, insight into the operative catalyst involved in the photocatalytic process is hitherto missing. Herein, we show through a combination of theoretical and experimental studies that the perceived heterogeneous photocatalysis with Bi2O3 in the presence of alkyl bromides involves a homogeneous BinBrm species, which is the true photocatalyst operative in the reaction. Hence, Bi2O3 can be regarded as a precatalyst which is slowly converted in an active homogeneous photocatalyst. This work can also be of importance to mechanistic studies involving other semiconductor-based photocatalytic processes.

Functional Properties of the Protein Isolate and Major Fractions of Pine Nut Proteins Prepared from the Changbai Mountain in China

2014 ◽  
Vol 881-883 ◽  
pp. 766-775 ◽  
Author(s):  
Dan Wu ◽  
Wei Hong Min ◽  
Jing Sheng Liu ◽  
Li Fang ◽  
Hong Mei Li ◽  
...  
Keyword(s):  
Amino Acids ◽  
Functional Properties ◽  
Protein Solubility ◽  
Essential Amino Acids ◽  
Protein Isolate ◽  
Absorption Capacity ◽  
Changbai Mountain ◽  
Major Protein ◽  
Pine Nut ◽  
A Value

The functional properties of protein isolate and major protein fractions prepared from Changbai Mountain pine nuts were investigated. Albumin, globulin, glutelin, and protein isolates were obtained after the Osborne method and alkaline dissolution and acid precipitation, and protein contents of the fractions are 48.02%, 81.93%, 83.02%, and 89.69%, respectively. For the sulfhydryl contents, albumin is the highest, and glutelin is the lowest. In a disulphide bond, the protein isolate content is the highest with a value of 28.74 μmol/g, and the glutelin content is the lowest with the value of 13.46 μmol/g. For the four kinds of proteins, the essential amino acids in percentage of total amino acids are 31.13%, 34.22%, 30.30%, and 34.54%, respectively. The pH dependent protein solubility profile reveals that the minimum solubility is at pH 5.0, which corresponds to the isoelectric point. Protein isolate has the minimum water absorption capacity with a value of 0.59 ml/g. On the other hand, albumin has the minimum oil absorption capacity with a value of 2.11 ml/g. The emulsifying activity and stability and the foaming activity and stability increased with increasing concentration of four kinds of proteins. SDS-PAGE results showed that these four kinds of proteins have different molecules.

scholarly journals Proposing a model for absorption capacity of technology

2015 ◽  
Vol 4 (1) ◽  
pp. 113 ◽  
Author(s):  
Hossein Gholizadeh ◽  
Ali Bonyadi Naeini ◽  
Alireza Moini
Keyword(s):  
Structural Equation Modeling ◽  
Structural Equation ◽  
Developed Countries ◽  
Absorption Capacity ◽  
Equation Modeling ◽  
Technological Gap ◽  
Expert Opinions ◽  
Modeling Analysis ◽  
Effective Dimensions

Absorption capacity of knowledge is the concept which is been introduced in this situation. This phenomenon describes why some countries are in a better condition with a view to technology. Many countries believe that the power to stay in the battle and excel other competitors directly depends on their abilities in taking knowledge. Many countries have used their technological gap with developed countries as an accelerator for improving their absorption capacity. In this study, authors tried to produce a complete definition for absorption capacity through analyzing different research. Then with using expert opinions, a categorization for dimensions of absorption capacity will be prepared by using the structural equation modeling analysis, and finally a model for measuring absorption capacity is suggested. The results show effective dimensions in 5 different section. Studies depict that the most important one is keeping which could be a fundamental for long-term policies of 1404.

In-Plane Asymmetries on the Ge(111)-c(2×8) Surface Mapped with the Scanning Tunneling Microscope

1992 ◽  
Vol 295 ◽  
Author(s):  
P. Molinàs-Mata ◽  
J. Zegenhagen ◽  
M. Böhringer ◽  
N. Takeuchi ◽  
A. Selloni
Keyword(s):  
Local Density ◽  
Experimental Studies ◽  
Surface States ◽  
Small Sample ◽  
Constant Current ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Low Energy Electron ◽  
Tunneling Currents ◽  
Insight Into

AbstractWe report on new experimental studies of the Ge(111)-c(2×8) reconstruction performed with low-energy electron diffraction. (LEED) and scanning tunneling microscopy (STM). Weak quarter-order reflections are present in the c(2 × 8) LEED pattern in agreement with previous observations and results of ab initio calculations. In order to gain insight into the predicted splitting of dangling bond states, we compare constant current topographs (CCT's) performed at high-tunneling currents (40.nA) with first-principles calculations of the local density of states (LDOS) 1Å above the surface adatoms and obtain good qualitative agreement. We finally discuss to what extent the STM CCT's at high tunneling currents (small sample-tip distances (STD)) are sensitive to surface states outside the Г point.

Embracing multidimensionality in phonological analysis

2021 ◽  
Vol 38 (1) ◽  
pp. 101-139
Author(s):  
Abigail C. Cohn ◽  
Margaret E. L. Renwick
Keyword(s):  
Native Speaker ◽  
Experimental Studies ◽  
Spoken Language ◽  
Iterative Approach ◽  
Full Spectrum ◽  
Multiple Factors ◽  
Multiple Data ◽  
Language Data ◽  
Corpus Data ◽  
Insight Into

Abstract We pursue the idea, implicit in much current phonological research, that understanding the multiple factors that shape speech production and perception is within the purview of phonology. In particular, increased access to naturalistic data has highlighted the multidimensional reality of variation in spoken language. At the same time, longstanding methods of doing phonology – including impressionistic analysis, and laboratory and experimental studies – remain crucial to understanding native speaker competence and grammar. We advocate for an expanded methodological toolbox in phonological analysis, using an iterative approach that crucially includes naturalistic corpus data. Integrating across multiple data sources offers fuller insight into the nature of the phonological system and native speaker-hearer ability. Several case studies highlight findings gained through linked, iterative studies, showing the importance of naturalistic data for a richer understanding of phonological phenomena, and leading us to reflect on desiderata for corpora to reveal speaker-specific patterns in fine phonetic detail and variability, which we argue are part of a speaker-hearer’s phonological competence. Phonological analysis that embraces the full spectrum of variation in spoken language data (from categorical to gradient, and systematic to sporadic) contributes to a deeper understanding of phonology in this richer sense.

Comparative studies of the physicochemical and functional properties of sweet potato (Ipomoea batatas L.) flour

Food Research ◽  
2021 ◽  
Vol 5 (4) ◽  
pp. 145-152
Author(s):  
M. Hasmadi ◽  
M. Merlynda ◽  
A.H. Mansoor ◽  
I. Salwa ◽  
M.K. Zainol ◽  
...  
Keyword(s):  
Sweet Potato ◽  
Functional Properties ◽  
Ipomoea Batatas ◽  
Absorption Capacity ◽  
Oil Absorption ◽  
Potato Flour ◽  
Foaming Capacity ◽  
Sweet Potato Flour ◽  
Physicochemical And Functional Properties ◽  
Dietary Fibre Content

This study aimed to determine the proximate compositions and functional properties of sweet potato flour from different varieties cultivated in Sabah, Malaysia, namely Jepun, Kairot and Kaladi. The results showed that the moisture content of all flour samples was below 14%. The fat and protein content of Jepun sweet potato variety were significantly different (p<0.05) as compared with Kairot and Kaladi sweet potato varieties. The ash and dietary fibre content of Kairot sweet potato flour were higher (p<0.05) compared to Jepun and Kaladi flours. In addition, Kaladi sweet potato had the highest carbohydrate content (82%). There were significant differences (p<0.05) in the values of L*, a* and b* for all sweet potato flours. The Jepun sweet potato flour had the highest foaming capacity, water absorption capacity, oil absorption capacity, swelling power and viscosity. Rapid Visco analyser revealed that significant differences were observed for pasting parameters such as peak viscosity, trough viscosity, breakdown viscosity, final viscosity and setback viscosity. The gelatinisation properties showed that Kairot sweet potato flour had the highest onset temperature, conclusion temperature and enthalpy while Kaladi sweet potato flour had the highest peak temperature.

scholarly journals Experimental Studies on Punching Shear and Impact Resistance of Steel Fibre Reinforced Slag Based Geopolymer Concrete

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Srinivasan Karunanithi
Keyword(s):  
Energy Absorption ◽  
Steel Fibre ◽  
Impact Load ◽  
Impact Resistance ◽  
Experimental Studies ◽  
Absorption Capacity ◽  
Punching Shear ◽  
Geopolymer Concrete ◽  
Energy Absorption Capacity ◽  
Ultimate Failure

The study was focused on slag based geopolymer concrete with the addition of steel fibre. The slag based geopolymer concrete was under shear load and sudden impact load to determine its response. The punching shear represents the load dissipation of the material and the energy absorption capacity of the geopolymer concrete to impact load. The various percentage of steel fibre in the slag based geopolymer concrete was 0.5%, 1.0%, and 1.5%. Overall the dosage 0.5% of steel fibre reinforced slag based geopolymer shows better results with a punching shear of 224 kN and 1.0% of steel fibre incorporated geopolymer concrete had the better energy absorption capacity with 3774.40 N·m for first crack toughness and 4123.88 N·m for ultimate failure toughness.

scholarly journals Photoselection of Luminescent Molecules in Anisotropic Media in the Case of Two-Photon Excitation. Part II. Experimental Studies of Hoechst 33342 in Stretched Polyvinyl alcohol) Films

1996 ◽  
Vol 51 (9) ◽  
pp. 1037-1041 ◽  
Author(s):  
A. Kawski ◽  
Z. Gryczyński ◽  
I. Gryczyński ◽  
J. R. Lakowicz ◽  
G. Piszczek
Keyword(s):  
Polyvinyl Alcohol ◽  
Vinyl Alcohol ◽  
Experimental Studies ◽  
Poly Vinyl Alcohol ◽  
Hoechst 33342 ◽  
Emission Anisotropy ◽  
Two Photon ◽  
Photon Excitation ◽  
Polyvinyl Alcohol Films ◽  
Two Photon Excitation

Abstract It was found by investigating dichroism and emission anisotropy in the case of one-and two-photon excitation of Hoechst 33342 [bis-benzimide,2,5'-bi-1H-benzimidazole, 2'-(4-ethoxyphenyl)-5-5(4-methyl-1-piperazinyl)] in stretched poly(vinyl alcohol) (PVA) films, that the absorption and fluorescence transition moments lie along the long molecular axis of the molecule studied. The slight deviation of the transition moment direction in fluorescence (about 8°) from that in absorption can be due to the incomplete linearity of the Hoechst molecule.

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