scholarly journals Construction of Porous Starch-Based Hydrogel via Regulating the Ratio of Amylopectin/Amylose for Enhanced Water-Retention

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3999
Author(s):  
Huiyuan Luo ◽  
Fuping Dong ◽  
Qian Wang ◽  
Yihang Li ◽  
Yuzhu Xiong

The performance of hydrogels prepared with traditional natural starch as raw materials is considerable; the fixed ratio of amylose/amylopectin significantly limits the improvement of hydrogel structure and performance. In this paper, starch hydrogels were prepared by physical blending and chemical grafting, with the aid of ultrasonic heating. The effects of different amylose/amylopectin ratios on the microstructure and water retention properties of starch hydrogels were studied. The results show that an increase in amylopectin content is beneficial to improve the grafting ratio of acrylamide (AM). The interaction between the AM grafted on amylopectin and amylose molecules through hydrogen bonding increases the pores of the gel network and thins the pore walls. When the amylopectin content was 70%, the water absorption (swelling 45.25 times) and water retention performance (16 days water retention rate 44.17%) were optimal. This study provides new insights into the preparation of starch-based hydrogels with excellent physical and chemical properties.

2008 ◽  
Vol 59 (11) ◽  
Author(s):  
Cristina Dusescu ◽  
Anca Borcea ◽  
Vasile Matei ◽  
Ion Popa ◽  
Irina Gabriela Radulescu

The present paper studies biodiesel samples preparation by transesterification and compares their physical and chemical properties (biofuels prepared from different raw materials - vegetable oils: sunflower oil, crocus oil and soya bean oil) and the biodegradability degree, as well as the possibilities of the integration of such production unit in industrial diagram of auto fuels production.


2018 ◽  
Vol 24 (21) ◽  
pp. 2425-2431 ◽  
Author(s):  
Cao Wu ◽  
Zhou Chen ◽  
Ya Hu ◽  
Zhiyuan Rao ◽  
Wangping Wu ◽  
...  

Crystallization is a significant process employed to produce a wide variety of materials in pharmaceutical and food area. The control of crystal dimension, crystallinity, and shape is very important because they will affect the subsequent filtration, drying and grinding performance as well as the physical and chemical properties of the material. This review summarizes the special features of crystallization technology and the preparation methods of nanocrystals, and discusses analytical technology which is used to control crystal quality and performance. The crystallization technology applications in pharmaceutics and foods are also outlined. These illustrated examples further help us to gain a better understanding of the crystallization technology for pharmaceutics and foods.


2021 ◽  
Vol 11 (8) ◽  
pp. 3334
Author(s):  
Jorge Suárez-Macías ◽  
Juan María Terrones-Saeta ◽  
Francisco Javier Iglesias-Godino ◽  
Francisco Antonio Corpas-Iglesias

Energy consumption, because of population development, is progressively increasing. For this reason, new sources of energy are being developed, such as that produced from the combustion of biomass. However, this type of renewable energy has one main disadvantage, the production of waste. Biomass bottom ash is a residue of this industry that currently has not much use. For this reason, this research evaluates its use as a filler in bituminous mixtures, since this sector also has a significant impact on the environment, as it requires large quantities of raw materials. With this objective, first, the physical and chemical properties of biomass bottom ashes were evaluated, verifying their characteristics for their use as filler. Subsequently, bituminous mixtures were conformed with biomass bottom ash as filler, and their physical and mechanical properties were analyzed through particle loss and Marshall tests. The results of these tests were compared with those obtained with the same type of mixture but with conventional and ophite aggregates. This study confirmed that biomass bottom ash was viable for use as a filler, creating mixtures with a higher percentage of bitumen, better mechanical behavior, and similar physical properties. In short, more sustainable material for roads was obtained with waste currently condemned to landfill.


2015 ◽  
Vol 19 (2) ◽  
pp. 39-50
Author(s):  
Inna Tiurikova ◽  
Mykhailo Peresichnyi

Abstract The results of studies in the field of beverage functionality using walnut are presented. The main components such as celery, Jerusalem artichokes, carrots, pumpkin and rhubarb, as a dietary supplement - extracts from walnut of milk-maturity stage are offered for creating blends. The basic physical and chemical properties of fruit and vegetable raw materials and semi-finished products created on the base of them have been studied, and their nutritional and biological value has been proved. Rational technologies of fruit and vegetable blends with nut additives have been identified. Their biological value has been confirmed. Drinks are recommended for use in the daily diet of human beings to satisfy thirst and enrich the body by biologically valuable components.


2020 ◽  
Vol 26 (1) ◽  
pp. 82-93
Author(s):  
Reihaneh Radmanesh ◽  
◽  
Mohsen Nabi Meybodi ◽  
Vahid Ramezani ◽  
Maryam Akrami ◽  
...  

Aims: Any pharmaceutical product made in pharmacy, hospital or factory may be contaminated with microbes. This contamination can originate from raw materials or during production. Hence, it is important to study the physical and chemical properties and stability of compounded drugs. Methods & Materials: In this study, first a specific sample of prescribed medication was ordered from 63 pharmacies in Yazd, Iran. After collecting the samples, the amount of microbial contamination, viscosity and particle size distribution and their stability were investigated and their results were compared to the standard levels. Findings: Based on the results, 31.7% of the samples had discoloration and 23.8% showed creaming phenomenon. In terms of particle size distribution, 57.1% of the samples had a 20-40 μm particle size and 49.2% had a viscosity equal to 2500-3000 centipoise. Regarding stability, 12.6% of the samples underwnet phase change at 30-40°C. About of the amount of hydroquinone in samples, 35% had acceptable amount. In 23.8% of the samples, fungal infection was observed. Conclusion: Contrary to a popular belief that the compounded medicines produced in pharmacies have microbial contamination, the results of this study showed that the microbial contamination of these compounded medications is low.


Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5530
Author(s):  
Meng Chen ◽  
Jianming Wei ◽  
Runhua Zhang ◽  
Lipei Jia ◽  
Qiqi Yao ◽  
...  

Manganese slag is a kind of industrial waste produced by electrolytic production of manganese metal. The traditional method of stacking manganese slag not only causes waste of resources, but also produces environmental pollution. Finding harmless, effective, and economical disposal technology of manganese slag has gradually become a research hotspot and difficulty in the field of electrolytic manganese industry and environmental protection. To verify the feasibility of using manganese slag as roadbed material, the basic physical and chemical properties of manganese slag were analyzed based on X-ray diffraction, X-ray fluorescence spectrum, SEM scanning electron microscope, and particle analysis, the basic engineering characteristics of raw materials of manganese slag and solidified manganese slag mixed with quicklime were analyzed through a compaction test and a CBR test. Finally, based on the Monte Carlo method, the stability of a highway slope in the Guizhou Province of China is simulated by the finite element method, considering the spatial variability of manganese slag material strength parameters. The results show that the solidified manganese slag material can be used as highway subgrade material. This study has important reference significance for manganese slag highway construction projects.


2018 ◽  
Vol 12 (3) ◽  
Author(s):  
O. O. Bondarchuk

Physical and chemical properties of cream multistep modes of ripening and fermentations are investigation and their role in the production of sour-cream butter is studied. The process of ripening of cream was carried out multistep, regimes were selected depending on seasonal changes in the composition of milk fat. For raw materials of the autumn-winter period, for the values of iodine number 29.1–34.5, the first stage of ripening was carried out at a temperature of 8°C for 2 hours, the second stage – at 21°C for 7 hours, the third stage – at 13°C for 10 hours. For raw of spring-summer period, for the values of iodine number 34.5–40.1, the first stage of ripening was carried out at 21°C for 6 hours, the second stage – at 13°C for 4 hours, the third stage – at 8°C for 8 hours. It has been established that individual modes of low-temperature cream preparation, taking into account seasonal changes in the composition of milk fat, make it possible to obtain cream before churning almost with the same indexes of effective viscosity. The content of the crystalline phase of milk fat under both temperature regimes was 38.7–40.1%, which is sufficient to obtain of proper consistency sour-cream butter. The content of diacetyl and volatile organic acids more depend on the level of fermentation of cream than on the technological regimes of ripening and seasonality of raw materials. It has been proved that an increase in the fermentation degree of cream promotes an increase in the acidity of plasma and the content of aroma-producing components in the butter, and, accordingly, affects the degree of the sour taste. It is recommended for the production of cultured butter to begin the cream when the acidity of the plasma reaches 60ºT, which ensures the formation of high sensorial characteristic of the finished product.


2020 ◽  
Vol 15 ◽  

This paper presents the results of practical mechanical tests of motor oils, their specifications and characteristics and the effect of their physical and chemical properties on the performance of the engine. The performance of the engine has a strong relation with the engine oil type and efficiency. The degree of stability of oils properties is very important because if oil or lubricants lose their properties, mechanical and chemical excessive corrosion of the motor metals may occur. Consequently, damage occurs to one or more parts of the engine, thereby the system is breaking down where the cost of downtime is too expensive. It has been found that a higher viscosity value is not the optimum as it increases temperature and energy consumption due to frictional losses. The values required for viscosity is the ideals that gives the stable results regardless temperature variations under any conditions of operation, at which the power losses are minimal and the fuel economy is optimal.


Author(s):  
T. Mamilov ◽  
◽  
G.S. Aitkaliyeva ◽  
A.B. Ismailova ◽  
M.A. Yelubay ◽  
...  

This paper presents the results of a study of the physical and chemical properties of samples of vegetable oils (sunflower, rapeseed, olive). It has been shown that the viscosity of oils varies from 41.4 to 61.7 cSt at a temperature of 40 ° C for olive and sunflower oils, respectively. The acid numbers of the oil samples were also determined, it was found that the lowest indicator is characteristic of sunflower oil. Pour points of oils also range from -3 to -16 ° C for olive and sunflower oils, respectively. Using the method of IR spectroscopy, functional groups in the composition of samples of vegetable oils were studied and it was shown that the composition of oils contains carbonyl and hydroxyl functional groups, indicating the presence of carboxylic acids. Based on studies of the physical and chemical properties of vegetable oils, it was found that sunflower, olive and rapeseed oils can serve as raw materials for the synthesis of biofuels based on them, since they contain free fatty acids. To obtain biodiesel fuel based on vegetable oils, it is planned to use the transesterification method in the presence of various catalysts (alkaline, acidic, and complex).


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