scholarly journals Biocomposites Using Whole or Valuable Component-Extracted Microalgae Blended with Polymers: A Review

Catalysts ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 25
Author(s):  
Gyu Min Kim ◽  
Won-Seok Chang ◽  
Young-Kee Kim

Global demand for plastics has increased steadily alongside industrial development. Despite their versatility and convenience, environmental pollution caused by plastics are a major issue. With a reduction in the market size of plastics being seemingly impossible, bioplastics may become key to tackle this issue. Among a wide range of sources of bioplastics, microalgae have come into the limelight. While abundant and valuable components in microalgae have the potential to replace preexisting plastics, complex processes and low cost performances have prevented them from entering the market. In this study, we examined techniques for biocomposites in which polymers are blended with microalgae. We focused on microalgae-based biocomposite blending processed from the perspective of functionality and cost performance.

2020 ◽  
Vol 17 (35) ◽  
pp. 1137-1147
Author(s):  
Sholpan BAKHTIYAROVA ◽  
Bolatbek ZHAKSYMOV ◽  
Unzira KAPYSHEVA ◽  
Oksana CHEREDNICHENKO

In Kazakhstan, due to the strengthening of the geopolitical role in the international arena and active industrial development, negative environmental impacts have intensified in recent years. Many regions are environmentally unfavorable and carry the risk of an increase in the incidence of living in these conditions of the population. Numerous deviations in the health of the community create the conditions for genetic polymorphism and the growth of certain groups of diseases characteristic of regions with environmental pollution. Long-term environmental pollution is the reason for the increase in the rate of the mutation process and the volume of the genetic load in the human population. The purpose of this study is to show the influence of dominant environmental factors in distant regions of Kazakhstan on cytogenetic disturbances in the body of the younger generation. Students from different schools aged 16 to 18 years living near the Semipalatinsk test site of the East Kazakhstan region and in the Aral region of the Kyzylorda region took part in the studies. The results of the study show that the oral epithelial cells in two-thirds of the examined adolescents living in environmentally unfavorable conditions either near the Semipalatinsk Test Site or in the Aral Sea region of Kazakhstan revealed a wide range of cytogenetic disorders. The most significant percentage of violations associated with the formation of micronuclei, protrusions, and apoptosis, was detected in urban students living 150 km from the Semipalatinsk Test Site. When comparing the data of urban and rural students, the predominant development of cytological disorders was revealed, such as nuclear destruction (karyorrhexis, karyolysis, and apoptosis) in rural adolescents, which indicates the ongoing negative impact of the closed Semipalatinsk Test Site and the salinization of the Aral Sea on the health of the younger generation of children.


2000 ◽  
Vol 41 (1) ◽  
pp. 69-72 ◽  
Author(s):  
S.Ç. Ayaz ◽  
I. Akca

The constructed wetland is a low-cost technology to control environmental pollution. The system is especially suitable for small settlements. An innovative constructed wetland technology is described in this paper. A pilot plant was used to assess the performance of the system. The experimental system consists of two serial connected tanks that settled up with fillers and Cyperus as treatment media. Wastewater is recycled periodically upward and downward between the two tanks. The treatment performance was monitored in different loading conditions in a one-year period. The average COD removal efficiency of 90% was observed at 122 g COD/m2.day average loading conditions. Other average removal values in the same conditions are as follows: suspended solid 95%, TKN 77%, total nitrogen 61%, PO4-P 39%. The land requirement for this system will be 0.82 m2 per capita when applying as full-scale system.


Author(s):  
Polly Jones

A major late Soviet initiative, the ‘Fiery Revolutionaries’ (Plamennye revoliutsionery) series, was launched to rekindle popular enthusiasm for the revolution, eventually giving rise to over 150 biographies and historical novels authored by many key post-Stalinist writers. What new meanings did revolution take on as it was reimagined by writers including dissidents, leading historians, and popular historical novelists? How did their millions of readers engage with these highly varied texts? To what extent does this Brezhnev-era publishing phenomenon challenge the notion of late socialism as a time of ‘stagnation’, and how does it confirm it? Through exploring the complex processes of writing, editing, censorship, and reading of late Soviet literature, Revolution Rekindled highlights the dynamic negotiations that continued within Soviet culture well past the apparent turning point of 1968 through to the late Gorbachev era. It also complicates the opposition between ‘official’ and underground post-Stalinist culture by showing how Soviet writers and readers engaged with both, as they sought answers to key questions of revolutionary history, ethics, and ideology: it thus reveals the enormous breadth and vitality of the ‘historical turn’ amongst the late Soviet population. Revolution Rekindled is the first archival, oral history, and literary study of this unique late socialist publishing experiment, from its beginnings in the early 1960s to its collapse in the early 1990s. It draws on a wide range of previously untapped archives, uses in-depth interviews with Brezhnev-era writers, editors, and publishers, and assesses the generic and stylistic innovations within the series’ biographies and novels.


2021 ◽  
pp. 096100062110165
Author(s):  
Mohammadhiwa Abdekhoda ◽  
Fatemeh Ranjbaran ◽  
Asghar Sattari

This study was conducted with the aim of evaluating the role of information and information resources in the awareness, control, and prevention of COVID-19. This study was a descriptive-analytical survey in which 450 participants were selected for the study. The data collection instrument was a researcher-made questionnaire. Descriptive and inferential statistics were used to analyze the data through SPSS. The findings show that a wide range of mass media has become well known as information resources for COVID-19. Other findings indicate a significant statistical difference in the rate of using information resources during COVID-19 based on age and gender; however, this difference is not significant regarding the reliability of information resources with regard to age and gender. Health information has an undisputable role in the prevention and control of pandemic diseases such as COVID-19. Providing accurate, reliable, and evidence-based information in a timely manner for the use of resources and information channels related to COVID-19 can be a fast and low-cost strategic approach in confronting this disease.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maria Elena Antinori ◽  
Marco Contardi ◽  
Giulia Suarato ◽  
Andrea Armirotti ◽  
Rosalia Bertorelli ◽  
...  

AbstractMycelia, the vegetative part of fungi, are emerging as the avant-garde generation of natural, sustainable, and biodegradable materials for a wide range of applications. They are constituted of a self-growing and interconnected fibrous network of elongated cells, and their chemical and physical properties can be adjusted depending on the conditions of growth and the substrate they are fed upon. So far, only extracts and derivatives from mycelia have been evaluated and tested for biomedical applications. In this study, the entire fibrous structures of mycelia of the edible fungi Pleurotus ostreatus and Ganoderma lucidum are presented as self-growing bio-composites that mimic the extracellular matrix of human body tissues, ideal as tissue engineering bio-scaffolds. To this purpose, the two mycelial strains are inactivated by autoclaving after growth, and their morphology, cell wall chemical composition, and hydrodynamical and mechanical features are studied. Finally, their biocompatibility and direct interaction with primary human dermal fibroblasts are investigated. The findings demonstrate the potentiality of mycelia as all-natural and low-cost bio-scaffolds, alternative to the tissue engineering systems currently in place.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1807
Author(s):  
Estefanía Álvarez-Castillo ◽  
José Manuel Aguilar ◽  
Carlos Bengoechea ◽  
María Luisa López-Castejón ◽  
Antonio Guerrero

Composite materials based on proteins and carbohydrates normally offer improved water solubility, biodegradability, and biocompatibility, which make them attractive for a wide range of applications. Soy protein isolate (SPI) has shown superabsorbent properties that are useful in fields such as agriculture. Alginate salts (ALG) are linear anionic polysaccharides obtained at a low cost from brown algae, displaying a good enough biocompatibility to be considered for medical applications. As alginates are quite hydrophilic, the exchange of ions from guluronic acid present in its molecular structure with divalent cations, particularly Ca2+, may induce its gelation, which would inhibit its solubilization in water. Both biopolymers SPI and ALG were used to produce composites through injection moulding using glycerol (Gly) as a plasticizer. Different biopolymer/plasticizer ratios were employed, and the SPI/ALG ratio within the biopolymer fraction was also varied. Furthermore, composites were immersed in different CaCl2 solutions to inhibit the amount of soluble matter loss and to enhance the mechanical properties of the resulting porous matrices. The main goal of the present work was the development and characterization of green porous matrices with inhibited solubility thanks to the gelation of alginate.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Duy Tung Phan ◽  
Chang Won Jung

AbstractAn electromagnetic pulse (EMP) with high energy can damage electronic equipment instantly within a wide range of thousands of kilometers. Generally, a metal plate placed inside a thick concrete wall is used against an EMP, but it is not suitable for an EMP shielding window, which requires not only strong shielding effectiveness (SE) but also optical transparency (OT). In this paper, we propose a very thin and optically transparent structure with excellent SE for EMP shielding window application. The proposed structure consists of a saltwater layer held between two glass substrates and two metal mesh layers on the outside of the glass, with a total thickness of less than 1.5 cm. The SE and OT of the structure are above 80 dB and 45%, respectively, which not only meet the requirement of EMP shielding for military purposes but also retain the procedure of good observation. Moreover, the OT of the structure can be significantly improved using only one metal mesh film (MMF) layer, while the SE is still maintained high to satisfy the required SE for home applicants. With the major advantages of low cost, optical transparency, strong SE, and flexible performance, the proposed structure can be considered a good solution for transparent EMP shielding windows.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shi Cao ◽  
Wei Hong ◽  
Ziqi Ye ◽  
Lei Gong

AbstractThe direct and selective C(sp3)-H functionalization of cycloalkanes and alkanes is a highly useful process in organic synthesis owing to the low-cost starting materials, the high step and atom economy. Its application to asymmetric catalysis, however, has been scarcely explored. Herein, we disclose our effort toward this goal by incorporation of dual asymmetric photocatalysis by a chiral nickel catalyst and a commercially available organophotocatalyst with a radical relay strategy through sulfur dioxide insertion. Such design leads to the development of three-component asymmetric sulfonylation involving direct functionalization of cycloalkanes, alkanes, toluene derivatives or ethers. The photochemical reaction of a C(sp3)-H precursor, a SO2 surrogate and a common α,β-unsaturated carbonyl compound proceeds smoothly under mild conditions, delivering a wide range of biologically interesting α-C chiral sulfones with high regio- and enantioselectivity (>50 examples, up to >50:1 rr and 95% ee). This method is applicable to late-stage functionalization of bioactive molecules, and provides an appealing access to enantioenriched compounds starting from the abundant hydrocarbon compounds.


2021 ◽  
pp. 088391152199784
Author(s):  
Nipun Jain ◽  
Shashi Singh

Development of an artificial tissue by tissue engineering is witnessed to be one of the long lasting clarified solutions for the damaged tissue function restoration. To accomplish this, a scaffold is designed as a cell carrier in which the extracellular matrix (ECM) performs a prominent task of controlling the inoculated cell’s destiny. ECM composition, topography and mechanical properties lead to different types of interactions between cells and ECM components that trigger an assortment of cellular reactions via diverse sensing mechanisms and downstream signaling pathways. The polysaccharides in the form of proteoglycans and glycoproteins yield better outcomes when included in the designed matrices. Glycosaminoglycan (GAG) chains present on proteoglycans show a wide range of operations such as sequestering of critical effector morphogens which encourage proficient nutrient contribution toward the growing stem cells for their development and endurance. In this review we discuss how the glycosylation aspects are of considerable importance in everyday housekeeping functions of a cell especially when placed in a controlled environment under ideal growth conditions. Hydrogels made from these GAG chains have been used extensively as a resorbable material that mimics the natural ECM functions for an efficient control over cell attachment, permeability, viability, proliferation, and differentiation processes. Also the incorporation of non-mammalian polysaccharides can elicit specific receptor responses which authorize the creation of numerous vigorous frameworks while prolonging the low cost and immunogenicity of the substance.


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