scholarly journals Geopolymers vs. Cement Matrix Materials: How Nanofiller Can Help a Sustainability Approach for Smart Construction Applications—A Review

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2007
Author(s):  
Marco Valente ◽  
Matteo Sambucci ◽  
Abbas Sibai
Keyword(s):  
New Technologies ◽  
Construction Materials ◽  
Cementitious Materials ◽  
Strength Properties ◽  
Mix Design ◽  
Cement Matrix ◽  
Synthesis Parameters ◽  
Greenhouse Emissions ◽  
Recent Developments ◽  
Curing Regime

In the direction of reducing greenhouse emissions and energy consumption related to the activities of the cement and concrete industry, the increasingly popular concept of eco-sustainability is leading to the development and optimization of new technologies and low impact construction materials. In this respect, geopolymers are spreading more and more in the cementitious materials field, exhibiting technological properties that are highly competitive to conventional Portland concrete mixes. In this paper, the mix design, mechanical properties, microstructural features, and mineralogical properties of geopolymer mixes are discussed, investigating the influence of the main synthesis parameters (curing regime, type of precursors, activator molarity, mix design) on the performance of the final product. Moreover, recent developments of geopolymer technology based on the integration of functional nanofillers are reported. The novelty of the manuscript is to provide a detailed collection of past and recent comparative studies between geopolymers and ordinary Portland concrete mixes in terms of strength properties, durability, fire resistance, and environmental impact by LCA analysis, intending to evaluate the advantages and limitations of this technology and direct research towards a targeted optimization of the material.

scholarly journals The Effect of Complex Modification on the Impedance of Cement Matrices

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 557
Author(s):  
Grigory Yakovlev ◽  
Černý Vít ◽  
Irina Polyanskikh ◽  
Anastasiya Gordina ◽  
Igor Pudov ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Electrical Conductivity ◽  
Negative Impact ◽  
Calcium Nitrate ◽  
Control Sample ◽  
Multiwall Carbon Nanotubes ◽  
Strength Loss ◽  
Cementitious Materials ◽  
Strength Properties ◽  
Cement Matrix

The research results presented in this article were obtained by joint scientific research on creatingcement materials with reduced impedance. It is known that functional additives added to impart electrically conductive properties have a negative impact on physical and mechanical characteristics of the material. This study suggests using the multiwall carbon nanotubes in the amount of 7% from binder mass as a functional additive. The results obtained prove that the addition of this amount of the modifier does not lead to a significant decrease of strength characteristics. Calcium nitrate in the amount of 1–7% was added in order to level the strength loss and to ensure the effective stable electrical conductivity. The multifunctionality of using this salt has been proven, which is manifested in the anti-frost and anticorrosive effects as well in enhancement of electrical conductivity. The optimal composition of the additive with 7% of carbon nanotubes and 3% of calcium nitrate ensures a reduced electrical impedance of cement matrix. The electrical conductivity was 2440 Ohm, while the decrease of strength properties was within 10% in comparison tothe control sample. The nature of changes in the microstructure were studied to determine the influence of complex modifications that showed significant changes in the morphology of the hydration products. The optimum electrical characteristics of cementitious materials are provided due to the uniform distribution of carbon nanotubes and the formation of a network of interconnected micropores filled with the solution of calcium nitrate that provides additional and stable electrical conductivity over time.

Setting and Strengthening Mechanisms of Cementitious Materials

1991 ◽  
Vol 245 ◽  
Author(s):  
W. Jiang ◽  
D.M. Roy
Keyword(s):  
Mechanical Properties ◽  
Setting Time ◽  
Construction Materials ◽  
Cementitious Materials ◽  
Cement Matrix ◽  
Chemical Characteristics ◽  
Strengthening Mechanisms ◽  
Portland Cements ◽  
Dental Cement ◽  
Physico Chemical

ABSTRACTThis paper highlights the physico-chemical characteristics of cementitious materials responsible for or involved in setting, and how these are related to the strengthening and mechanical properties. Five main mechanisms which can be used to increase cementitious materials strength were discussed. The substantially improved cement matrix materials can be obtained by deliberately using one or more above mechanisms. Experiments have been performed on ordinary portland cements and phosphate cements used as construction materials, whose setting time is several hours, and dental cement, whose setting time is several minutes.

Recent Developments of Ambulatory Assessment Methods

2014 ◽  
Vol 25 (4) ◽  
pp. 279-287 ◽  
Author(s):  
Stefan Hey ◽  
Panagiota Anastasopoulou ◽  
André Bideaux ◽  
Wilhelm Stork
Keyword(s):  
Real Time ◽  
Information And Communication Technologies ◽  
New Technologies ◽  
Psychological Research ◽  
Ambulatory Assessment ◽  
Emotional States ◽  
Recent Developments ◽  
Potential Applications ◽  
Information And Communication ◽  
Physiological Sensors

Ambulatory assessment of emotional states as well as psychophysiological, cognitive and behavioral reactions constitutes an approach, which is increasingly being used in psychological research. Due to new developments in the field of information and communication technologies and an improved application of mobile physiological sensors, various new systems have been introduced. Methods of experience sampling allow to assess dynamic changes of subjective evaluations in real time and new sensor technologies permit a measurement of physiological responses. In addition, new technologies facilitate the interactive assessment of subjective, physiological, and behavioral data in real-time. Here, we describe these recent developments from the perspective of engineering science and discuss potential applications in the field of neuropsychology.

3D Printing in Pharmaceuticals: Regulatory Perspective

2019 ◽  
Vol 24 (42) ◽  
pp. 5081-5083 ◽  
Author(s):  
Mohd. A. Mirza ◽  
Zeenat Iqbal
Keyword(s):  
New Technologies ◽  
Pharmaceutical Product ◽  
Regulatory Agencies ◽  
Major Research ◽  
Data Bases ◽  
Drug Products ◽  
Regulatory Perspective ◽  
Regulatory Guidelines ◽  
Recent Developments ◽  
Technical Issues

Background: The last few decades have witnessed enormous advancements in the field of Pharmaceutical drug, design and delivery. One of the recent developments is the advent of 3DP technology. It has earlier been successfully employed in fields like aerospace, architecture, tissue engineering, biomedical research, medical device and others, has recently forayed into the pharmaceutical industry.Commonly understood as an additive manufacturing technology, 3DP aims at delivering customized drug products and is the most acceptable form of“personalized medicine”. Methods: Data bases and search engines of regulatory agencies like USFDA and EMA have been searched thoroughly for relevant guidelines and approved products. Other portals like PubMed and Google Scholar were also ferreted for any relevant repository of publications are referred to wherever required. Results: So far only one pharmaceutical product has been approved in this category by USFDA and stringent regulatory agencies are working over the drafting of guidelines and technical issues. Major research of this category belongs to the academic domain. Conclusion: It is also implicit to such new technologies that there would be numerous challenges and doubts before these are accepted as safe and efficacious. The situation demands concerted and cautious efforts to bring in foolproof regulatory guidelines which would ultimately lead to the success of this revolutionary technology.

Mass Spectrometry for Proteomics and Recent Developments in ESI, MALDI and other Ionization Methodologies

2019 ◽  
Vol 16 (4) ◽  
pp. 267-276
Author(s):  
Qurat ul Ain Farooq ◽  
Noor ul Haq ◽  
Abdul Aziz ◽  
Sara Aimen ◽  
Muhammad Inam ul Haq
Keyword(s):  
Mass Spectrometry ◽  
Electrospray Ionization ◽  
New Technologies ◽  
Protein Complexes ◽  
Imaging Techniques ◽  
Desorption Electrospray Ionization ◽  
High Throughput Analysis ◽  
Enhanced Sensitivity ◽  
Recent Developments ◽  
The Way

Background: Mass spectrometry is a tool used in analytical chemistry to identify components in a chemical compound and it is of tremendous importance in the field of biology for high throughput analysis of biomolecules, among which protein is of great interest. Objective: Advancement in proteomics based on mass spectrometry has led the way to quantify multiple protein complexes, and proteins interactions with DNA/RNA or other chemical compounds which is a breakthrough in the field of bioinformatics. Methods: Many new technologies have been introduced in electrospray ionization (ESI) and Matrixassisted Laser Desorption/Ionization (MALDI) techniques which have enhanced sensitivity, resolution and many other key features for the characterization of proteins. Results: The advent of ambient mass spectrometry and its different versions like Desorption Electrospray Ionization (DESI), DART and ELDI has brought a huge revolution in proteomics research. Different imaging techniques are also introduced in MS to map proteins and other significant biomolecules. These drastic developments have paved the way to analyze large proteins of >200kDa easily. Conclusion: Here, we discuss the recent advancement in mass spectrometry, which is of great importance and it could lead us to further deep analysis of the molecules from different perspectives and further advancement in these techniques will enable us to find better ways for prediction of molecules and their behavioral properties.

scholarly journals Mortars with Recycled Aggregates from Building-Related Processes: A ‘Four-Step’ Methodological Proposal for a Review

2021 ◽  
Vol 13 (5) ◽  
pp. 2756
Author(s):  
Federica Vitale ◽  
Maurizio Nicolella
Keyword(s):  
Building Materials ◽  
Thermal Analyses ◽  
Construction Materials ◽  
Physical And Mechanical Properties ◽  
Research Trends ◽  
Mix Design ◽  
Recycled Aggregates ◽  
Design Parameters ◽  
Natural Aggregates ◽  
By Products

Because the production of aggregates for mortar and concrete is no longer sustainable, many attempts have been made to replace natural aggregates (NA) with recycled aggregates (RA) sourced from factories, recycling centers, and human activities such as construction and demolition works (C&D). This article reviews papers concerning mortars with fine RA from C&D debris, and from the by-products of the manufacturing and recycling processes of building materials. A four-step methodology based on searching, screening, clustering, and summarizing was proposed. The clustering variables were the type of aggregate, mix design parameters, tested properties, patents, and availability on the market. The number and the type of the clustering variables of each paper were analysed and compared. The results showed that the mortars were mainly characterized through their physical and mechanical properties, whereas few durability and thermal analyses were carried out. Moreover, few fine RA were sourced from the production waste of construction materials. Finally, there were no patents or products available on the market. The outcomes presented in this paper underlined the research trends that are useful to improve the knowledge on the suitability of fine RA from building-related processes in mortars.

scholarly journals Machine Learning Approaches for Prediction of the Compressive Strength of Alkali Activated Termite Mound Soil

2021 ◽  
Vol 11 (11) ◽  
pp. 4754
Author(s):  
Assia Aboubakar Mahamat ◽  
Moussa Mahamat Boukar ◽  
Nurudeen Mahmud Ibrahim ◽  
Tido Tiwa Stanislas ◽  
Numfor Linda Bih ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Construction Materials ◽  
Curing Temperature ◽  
Sustainable Construction ◽  
Support Vector ◽  
Learning Approaches ◽  
Artificial Neural Network Ann ◽  
Curing Regime ◽  
Alkali Activated

Earth-based materials have shown promise in the development of ecofriendly and sustainable construction materials. However, their unconventional usage in the construction field makes the estimation of their properties difficult and inaccurate. Often, the determination of their properties is conducted based on a conventional materials procedure. Hence, there is inaccuracy in understanding the properties of the unconventional materials. To obtain more accurate properties, a support vector machine (SVM), artificial neural network (ANN) and linear regression (LR) were used to predict the compressive strength of the alkali-activated termite soil. In this study, factors such as activator concentration, Si/Al, initial curing temperature, water absorption, weight and curing regime were used as input parameters due to their significant effect in the compressive strength. The experimental results depict that SVM outperforms ANN and LR in terms of R2 score and root mean square error (RMSE).

scholarly journals The Ontogeny and Function of Placental Macrophages

2021 ◽  
Vol 12 ◽  
Author(s):  
Jake R. Thomas ◽  
Praveena Naidu ◽  
Anna Appios ◽  
Naomi McGovern
Keyword(s):  
Human Placenta ◽  
Outer Layer ◽  
New Technologies ◽  
Placental Development ◽  
Fetal Health ◽  
Hofbauer Cells ◽  
Recent Developments ◽  
Placental Macrophages ◽  
And Function ◽  
Insight Into

The placenta is a fetal-derived organ whose function is crucial for both maternal and fetal health. The human placenta contains a population of fetal macrophages termed Hofbauer cells. These macrophages play diverse roles, aiding in placental development, function and defence. The outer layer of the human placenta is formed by syncytiotrophoblast cells, that fuse to form the syncytium. Adhered to the syncytium at sites of damage, on the maternal side of the placenta, is a population of macrophages termed placenta associated maternal macrophages (PAMM1a). Here we discuss recent developments that have led to renewed insight into our understanding of the ontogeny, phenotype and function of placental macrophages. Finally, we discuss how the application of new technologies within placental research are helping us to further understand these cells.

scholarly journals Strength Attainment of Geopolymer Concrete with GGBS at Ambient Curing

2019 ◽  
Vol 9 (2S2) ◽  
pp. 56-59
Keyword(s):  
Tensile Strength ◽  
Ambient Temperature ◽  
Sodium Hydroxide ◽  
Cross Sections ◽  
Strength Properties ◽  
Industrial Wastes ◽  
Mix Design ◽  
Geopolymer Concrete ◽  
Ambient Curing ◽  
Test Result

Geopolymer concrete plays a major role in concrete industry by replacing cement and using the industrial wastes. In this study, the cement is completely replaced by GGBS and strength properties are analyzed. An M30 mix design is prepared and the specimens are cast and tested. For this, sodium hydroxide and sodium silicate are used as activator and its ratio is fixed as 1:2.5. Sodium hydroxide of 12 molarity, 550kg/m3 of GGBS is used in the study. Admixture La Hypercrete S25 (HTS code 38244090) is added in the mix by 1% of weight of GGBS to obtain the required workability. For compression study, cubes in 100 mm size are cast. Cylinders with 100mm dia and 200mm height are tested for splitting tensile strength and beam specimens of 500mm long and 100mm cross sections were cast for determining the flexure behaviour. The beams are subjected to ambient curing and tested at 3, 7, 14, 28 and 56 days. The test result shows that there is a gradual increment in all the strengths from 3 to 56 days and it proves that geopolymer concrete with GGBS cured at ambient temperature performs well in the strength properties.

scholarly journals Economic and non-economic values and objectives in the EU’s international trade: Normative tensions, actors and processes

2019 ◽  
Author(s):  
Urszula Jaremba ◽  
Machiko Kanetake ◽  
Ingrid Koning
Keyword(s):  
Sustainable Development ◽  
Human Rights ◽  
New Technologies ◽  
Economic Values ◽  
Trade Relations ◽  
Trade Law ◽  
Law And Policy ◽  
Recent Developments ◽  
The One ◽  
The Impact

This Europe and the World: A law review special issue comprises selected papers presented at a RENFORCE workshop on the theme of tensions between the EU’s trade and non-economic values, held at Utrecht University in November 2017. The symposium addresses normative dilemmas underlying the EU’s trade law and policy. Normative dilemmas subsist between, on the one hand, the EU’s basic pursuit of its commercial interests and trade liberalization, and, on the other hand, the EU’s mandate to promote and safeguard a number of non-economic values, including human rights and sustainable development. The journal symposium aims to unveil normative tensions existing in the EU’s trade and investment policy, and understand some of the key actors and processes through which normative tensions are created and also mitigated. While the tensions between economic and non-economic values in the EU’s trade law and policy have been extensively discussed in literature, the present symposium highlights some of the recent developments in the EU’s trade relations, analyses not only human rights but also sustainable development, and examines the impact of new technologies.

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