scholarly journals A review on the potential of filamentous fungi for microbial self-healing of concrete

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Aurélie Van Wylick ◽  
Antonielle Vieira Monclaro ◽  
Elise Elsacker ◽  
Simon Vandelook ◽  
Hubert Rahier ◽  
...  

AbstractConcrete is the most used construction material worldwide due to its abundant availability and inherent ease of manufacturing and application. However, the material bears several drawbacks such as the high susceptibility for crack formation, leading to reinforcement corrosion and structural degradation. Extensive research has therefore been performed on the use of microorganisms for biologically mediated self-healing of concrete by means of CaCO3 precipitation. Recently, filamentous fungi have been recognized as high-potential microorganisms for this application as their hyphae grow in an interwoven three-dimensional network which serves as nucleation site for CaCO3 precipitation to heal the crack. This potential is corroborated by the current state of the art on fungi-mediated self-healing concrete, which is not yet extensive but valuable to direct further research. In this review, we aim to broaden the perspectives on the use of fungi for concrete self-healing applications by first summarizing the major progress made in the field of microbial self-healing of concrete and then discussing pioneering work that has been done with fungi. Starting from insights and hypotheses on the types and principles of biomineralization that occur during microbial self-healing, novel potentially promising candidate species are proposed based on their abilities to promote CaCO3 formation or to survive in extreme conditions that are relevant for concrete. Additionally, an overview will be provided on the challenges, knowledge gaps and future perspectives in the field of fungi-mediated self-healing concrete.

2020 ◽  
Vol 20 (4) ◽  
pp. 175-205
Author(s):  
Aigul S. Istomina ◽  
◽  
Olga V. Bushkova ◽  

The second part of the review describes the prospects of using alternative polymer binders for composite electrodes of lithium electrochemical systems. Possible options having been taken into account, the most popular commercially-available synthetic polymers with functional group (the ones forming aqueous solutions or dispersions predominantly) and water-soluble polymers of natural origin are considered. The versatility of such materials is their distinctive feature. The availability of salt forms for natural and synthetic polymers, many of which are polyelectrolytes, makes it possible to significantly affect the ion transfer in the composite electrode mass, reducing the polarization of the electrodes and improving the power characteristics of batteries. The ability to form “artificial SEI” and / or form a three-dimensional network with self-healing cross-links between macromolecules allows long-term safe cycling, the latter being especially important for active materials with very large volume changes during lithium intercalation / deintercalation (e.g. silicon).


2020 ◽  
Vol 11 (8-2020) ◽  
pp. 83-91
Author(s):  
A.V. Trashkova ◽  
◽  
A.V. Vicentiy ◽  

The paper discusses the current state of simulators development to provide professional training in mining. A brief description of the mostcommon types of simulators is given. A choice has been made in favour of implementing a VR simulator for a digital career. A brief description of the current state of development of the project for a three-dimensional modeling system for open-pit mining operations is given.


1983 ◽  
Vol 22 (1) ◽  
pp. 57-61
Author(s):  
Shahrukh Rafi Khan

The book under review is a compilation of the author's articles and lectures that highlight the prominent developments in the literature on the subject of Islamic banking and inform the reader of the current state of debate on it. One of the earliest and main contributors to this topic is the author himself. The focus of this review will mainly be on "Economics of Profit-Sharing", which is the title of the fourth chapter of the book and is among his latest contributions. This chapter is a significant contribution as it is the first attempt to formalise the concept of profit sharing into an analytical model and, therefore, demands closer scrutiny. However, in the remaining chapters of the book, the author has drawn attention to some of the fine points made in the literature on this topic. Since some of these points appear to be controversial to me, I will briefly discuss them before moving on to the analytical chapter of the book.


2020 ◽  
Vol 10 (2) ◽  
pp. 133-148
Author(s):  
Ankaj Kaundal ◽  
Pravin Kumar ◽  
Rajendra Awasthi ◽  
Giriraj T. Kulkarni

Aim: The study was aimed to develop mucoadhesive buccal tablets using Aster ericoides leaves mucilage. Background : Mucilages are naturally occurring high-molecular-weight polyuronides, which have been extensively studied for their application in different pharmaceutical dosage forms. Objective: The objective of the present research was to establish the mucilage isolated from the leaves of Aster ericoides as an excipient for the formulation of the mucoadhesive buccal tablet. Method: The mucilage was isolated from the leaves of Aster ericoides by maceration, precipitated with acetone and characterized. Tablets were prepared using wet granulation technique and evaluated for various official tests. Results: The mucilage was found to be non-toxic on A-431 and Vero cell lines. It was insoluble but swellable in cold and hot water. The results indicate that mucilage can form a three-dimensional network. The pH of the mucilage (6.82 ± 0.13) indicated that it might be non-irritant to the buccal cavity. The mucilage was found to be free from microbes. The release of drug was by Fickian diffusion. The in vivo buccal tablet acceptance was 80%. No significant difference between the diastolic blood pressure of standard and Aster tablets treated volunteer group was recorded. Conclusion: The mucilage was found to be non-toxic on A-431 and Vero cell lines. It was insoluble but swellable in cold and hot water. The results indicate that mucilage can form a three-dimensional network. The pH of the mucilage (6.82 ± 0.13) indicated that it might be non-irritant to the buccal cavity. The mucilage was found to be free from microbes. The release of drug was by Fickian diffusion. The in vivo buccal tablet acceptance was 80%. No significant difference between the diastolic blood pressure of standard and Aster tablets treated volunteer group was recorded. Other: However, to prove the potency of the polymer, in vivo bioavailability studies in human volunteers are needed along with chronic toxicity studies in suitable animal models.


Author(s):  
Serge Reynaud ◽  
Astrid Lambrecht

The Casimir force is an effect of quantum vacuum field fluctuations, with applications in many domains of physics. The ideal expression obtained by Casimir, valid for perfect plane mirrors at zero temperature, has to be modified to take into account the effects of the optical properties of mirrors, thermal fluctuations, and geometry. After a general introduction to the Casimir force and a description of the current state of the art for Casimir force measurements and their comparison with theory, this chapter presents pedagogical treatments of the main features of the theory of Casimir forces for one-dimensional model systems and for mirrors in three-dimensional space.


2014 ◽  
Vol 70 (9) ◽  
pp. i46-i46 ◽  
Author(s):  
Matthias Weil ◽  
Thomas Häusler

The crystal structure of the room-temperature modification of K[Hg(SCN)3], potassium trithiocyanatomercurate(II), was redetermined based on modern CCD data. In comparison with the previous report [Zhdanov & Sanadze (1952).Zh. Fiz. Khim.26, 469–478], reliability factors, standard deviations of lattice parameters and atomic coordinates, as well as anisotropic displacement parameters, were revealed for all atoms. The higher precision and accuracy of the model is, for example, reflected by the Hg—S bond lengths of 2.3954 (11), 2.4481 (8) and 2.7653 (6) Å in comparison with values of 2.24, 2.43 and 2.77 Å. All atoms in the crystal structure are located on mirror planes. The Hg2+cation is surrounded by four S atoms in a seesaw shape [S—Hg—S angles range from 94.65 (2) to 154.06 (3)°]. The HgS4polyhedra share a common S atom, building up chains extending parallel to [010]. All S atoms of the resulting1∞[HgS2/1S2/2] chains are also part of SCN−anions that link these chains with the K+cations into a three-dimensional network. The K—N bond lengths of the distorted KN7polyhedra lie between 2.926 (2) and 3.051 (3) Å.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1841
Author(s):  
Kang Li ◽  
Xuejie Zhang ◽  
Yan Qin ◽  
Ying Li

Aerogels have been widely used in the adsorption of pollutants because of their large specific surface area. As an environmentally friendly natural polysaccharide, cellulose is a good candidate for the preparation of aerogels due to its wide sources and abundant polar groups. In this paper, an approach to construct cellulose nanofibers aerogels with both the good mechanical property and the high pollutants adsorption capability through chemical crosslinking was explored. On this basis, TiO2 nanoparticles were loaded on the aerogel through the sol-gel method followed by the hydrothermal method, thereby the enriched pollutants in the aerogel could be degraded synchronously. The chemical cross-linker not only helps build the three-dimensional network structure of aerogels, but also provides loading sites for TiO2. The degradation efficiency of pollutants by the TiO2@CNF Aerogel can reach more than 90% after 4 h, and the efficiency is still more than 70% after five cycles. The prepared TiO2@CNF Aerogels have high potential in the field of environmental management, because of the high efficiency of treating organic pollutes and the sustainability of the materials. The work also provides a choice for the functional utilization of cellulose, offering a valuable method to utilize the large amount of cellulose in nature.


RSC Advances ◽  
2021 ◽  
Vol 11 (33) ◽  
pp. 20446-20456
Author(s):  
Xi Ma ◽  
Ziwei Wang ◽  
Haoguo Yang ◽  
Yiqiu Zhang ◽  
Zizhong Zhang ◽  
...  

Compared with traditional layered graphene, graphene hydrogels have been used to construct highly efficient visible light-excited photocatalysts due to their particular three-dimensional network structure and efficient electron transport capacity.


Sign in / Sign up

Export Citation Format

Share Document