scholarly journals Durability of UHPFRC functionalised with nanoadditives due to synergies in the action of sulphate and chloride in cracked and uncracked states

2021 ◽  
Vol 71 (344) ◽  
pp. e264
Author(s):  
M. Giménez ◽  
M.C. Alonso ◽  
E. Menéndez ◽  
M. Criado
Keyword(s):  
High Performance ◽  
Water Impact ◽  
Chemical Parameters ◽  
Calcium Carbonates ◽  
Water Interaction ◽  
Rich Media ◽  
The Matrix ◽  
Rich Solution ◽  
Physical And Chemical ◽  
Furnace Slag

This paper studies the durability of Ultra High Performance Fibre Reinforced Concrete (UHPFRC) with high Blast Furnace Slag content (BFS) and nanoadditives such as crystalline admixture (CA), alumina nanofibres (ANF) and cellulose nanocrystals (CNC), exposed to different aggressive environmental conditions: 1) three aggressive media: a) deionized water (dw), b) sulphate rich solution (ss) and c) simulated geothermal water (sgw) containing sulphate and chloride; 2) two water interaction conditions: a) static and b) dynamic (water impact); and 3) with and without the presence of cracks. Durability was analysed over 24 months, measuring several physical and chemical parameters of the system, recording changes in both the aggressive media and the concrete. All UHPFRC types demonstrate good durability, showing high resistance to expansion and deformation in the sulphate-rich media. A leaching process occurs in all water interaction systems, the dynamic interaction in sgw being the most aggressive. The interaction of sgw inside the crack favours the formation of solid phases such as calcium carbonates and ettringite, while the presence of nanoadditives affects the response of both the matrix and the formation of precipitates within the crack.

scholarly journals Phytochemical analysis of the main groups of secondary metabolites in the Dracocephalum moldavica L. herb

2021 ◽  
pp. 85-93
Author(s):  
М. І. Шанайда
Keyword(s):  
Phenolic Compounds ◽  
Secondary Metabolites ◽  
Essential Oil ◽  
High Performance ◽  
Raw Material ◽  
Phytochemical Analysis ◽  
Chemical Parameters ◽  
Physical And Chemical Parameters ◽  
Physical And Chemical ◽  
Layer Chromatography

The genus Dragonhead (Dracocephalum L.) includes 72 species of essential oil-bearing plants belonging to the Lamiaceae family. Many of them have long been used in a folk medicine of different countries. Moldavian dragonhead (D. moldavica L.) has been identified as the most promising species for the complex phytochemical research since it was successfully introduced in the climatic conditions of the Ukrainian forest-steppe zone and due to the presence of its various botanical forms and varieties. The aim of this study was the phytochemical analysis of the main groups of secondary metabolites in the herb of violet-flowered form of Moldavian dragonhead  (D. moldavica L.) under its cultivation in Ternopil region (Ukraine). The herb of the plant was harvested in July of 2018‒2019 years during the flowering period. The essential oil was obtained from the plant raw material by the hydrodistillation. Such physical and chemical parameters of the essential oil as a relative density, refractive index, optical rotation, acid number and solubility in ethanol were studied. The method of thin layer chromatography (TLC) was used to determine the specific sequence of bands in the chromatograms of essential oil. The method of high-performance thin-layer chromatography (HPTLC) was used for the identification of phenolic compounds in the herb. The component composition of polyphenols was determined by the high performance liquid chromatography (HPLC). The specific physical and chemical parameters as well as the «chromatographic profile» of essential oil have been established. The main compounds of the polyphenolic nature were revealed by the chromatographic methods. In particular, rosmarinic and caffeic hydroxycinnamic acids were identified in the methanol extract of herb by the HPTLC method. The HPLC analysis of phenolic compounds in the 70% ethanol extract of raw material established that rosmarinic acid was its main polyphenol. It was found the decreasing of polyphenol contents in the D. moldavica herb in such direction: rosmarinic acid (3.01%) > apigenin-7-О-glucoside (0.67%) > apigenin (0.29%) > caffeic acid (0.28%) > luteolin-7-О-glucoside (0.13%)> hyperoside (0.12%) > ferulic acid (0.09%) > chlorogenic acid (0.08%). The obtained data could be used for planning pharmacological studies of the phytosubstances developed from the Moldavian dragonhead herb.

scholarly journals The assessment of the amount of water pollution and its suitability for drinking of the Tyśmienica River Basin, Poland

2021 ◽  
Vol 193 (5) ◽  
Author(s):  
Antoni Grzywna ◽  
Joanna Sender
Keyword(s):  
River Basin ◽  
High Performance ◽  
Ph Value ◽  
Ecological Status ◽  
Polluted Water ◽  
Chemical Parameters ◽  
Measuring Point ◽  
Physical And Chemical Parameters ◽  
Good Ecological Status ◽  
Physical And Chemical

AbstractThe quality and potability of waters of the Tyśmienica River Basin were determined in 2017 at eight measuring stations. The paper presents analyses of the physical and chemical parameters of surface waters of the basin. With regard to suspended solids, pH value, electric conductivity, sulphates, ammonia, chlorides and phosphate, the water was classified as having a very good ecological status. In the case of Kjeldahl nitrogen, the waters were classified as having a good ecological status. In the case of the remaining parameters, i.e. BOD, DO, TOC and COD, the status varied among stations. The values of all the physical and chemical parameters complied with the values for undisturbed conditions. Only ammonia and COD showed significant differences among stations. The WPI values for each measuring point ranged from 0.90 to 1.56, what corresponds to the descriptive indicators of moderately polluted water. The high concentrations of COD and TOC indicate that high-performance treatment processes (category A3) must be used to ensure that the water is suitable for drinking.

Morphology of High-Performance Rigid-Rod Polymer Fibers and Molecular Composites

1989 ◽  
Vol 47 ◽  
pp. 338-339
Author(s):  
W.W. Adams ◽  
S. J. Krause
Keyword(s):  
Tensile Strength ◽  
High Performance ◽  
Liquid Crystalline ◽  
Molecular Level ◽  
Synergistic Effects ◽  
Tensile Modulus ◽  
Commercial Development ◽  
The Matrix ◽  
Molecular Composites ◽  
Rigid Rod

Rigid-rod polymers such as PBO, poly(paraphenylene benzobisoxazole), Figure 1a, are now in commercial development for use as high-performance fibers and for reinforcement at the molecular level in molecular composites. Spinning of liquid crystalline polyphosphoric acid solutions of PBO, followed by washing, drying, and tension heat treatment produces fibers which have the following properties: density of 1.59 g/cm3; tensile strength of 820 kpsi; tensile modulus of 52 Mpsi; compressive strength of 50 kpsi; they are electrically insulating; they do not absorb moisture; and they are insensitive to radiation, including ultraviolet. Since the chain modulus of PBO is estimated to be 730 GPa, the high stiffness also affords the opportunity to reinforce a flexible coil polymer at the molecular level, in analogy to a chopped fiber reinforced composite. The objectives of the molecular composite concept are to eliminate the thermal expansion coefficient mismatch between the fiber and the matrix, as occurs in conventional composites, to eliminate the interface between the fiber and the matrix, and, hopefully, to obtain synergistic effects from the exceptional stiffness of the rigid-rod molecule. These expectations have been confirmed in the case of blending rigid-rod PBZT, poly(paraphenylene benzobisthiazole), Figure 1b, with stiff-chain ABPBI, poly 2,5(6) benzimidazole, Fig. 1c A film with 30% PBZT/70% ABPBI had tensile strength 190 kpsi and tensile modulus of 13 Mpsi when solution spun from a 3% methane sulfonic acid solution into a film. The modulus, as predicted by rule of mixtures, for a film with this composition and with planar isotropic orientation, should be 16 Mpsi. The experimental value is 80% of the theoretical value indicating that the concept of a molecular composite is valid.

What Can Digitization Do For Formulated Product Innovation and Development

2020 ◽  
Author(s):  
James McDonagh ◽  
William Swope ◽  
Richard L. Anderson ◽  
Michael Johnston ◽  
David J. Bray
Keyword(s):  
High Performance ◽  
Quality Data ◽  
High Quality Data ◽  
Base Level ◽  
Hybrid Approaches ◽  
Digital Ecosystem ◽  
Recent Developments ◽  
Chemical Simulation ◽  
High Level ◽  
Physical And Chemical

Digitization offers significant opportunities for the formulated product industry to transform the way it works and develop new methods of business. R&D is one area of operation that is challenging to take advantage of these technologies due to its high level of domain specialisation and creativity but the benefits could be significant. Recent developments of base level technologies such as artificial intelligence (AI)/machine learning (ML), robotics and high performance computing (HPC), to name a few, present disruptive and transformative technologies which could offer new insights, discovery methods and enhanced chemical control when combined in a digital ecosystem of connectivity, distributive services and decentralisation. At the fundamental level, research in these technologies has shown that new physical and chemical insights can be gained, which in turn can augment experimental R&D approaches through physics-based chemical simulation, data driven models and hybrid approaches. In all of these cases, high quality data is required to build and validate models in addition to the skills and expertise to exploit such methods. In this article we give an overview of some of the digital technology demonstrators we have developed for formulated product R&D. We discuss the challenges in building and deploying these demonstrators.<br>

The influence of gelatin and starter culture on the physical and chemical parameters of cheeses with different fat content

2018 ◽  
Vol 6 (10) ◽  
pp. 123-130
Author(s):  
Yaroslava Zhukova ◽  
◽  
Pylyp Petrov ◽  
Olena Boloba ◽  
Tetiana Ohrimenko ◽  
...  
Keyword(s):  
Starter Culture ◽  
Fat Content ◽  
Chemical Parameters ◽  
Physical And Chemical Parameters ◽  
Physical And Chemical

High-Performance Natural Rubber/Graphene Composites from a Uniquely Designed Physical and Chemical Hybrid-Network

2020 ◽  
Vol 35 (2) ◽  
pp. 146-157
Author(s):  
B.-L. Yu ◽  
L.-C. Jiang ◽  
K. Huang ◽  
X.-L. Liu ◽  
X.-M. Shao ◽  
...  
Keyword(s):  
Natural Rubber ◽  
High Performance ◽  
Hybrid Network ◽  
Physical And Chemical

Life in Glacial and Alpine Rivers in Central Iceland in Relation to Physical and Chemical Parameters

2000 ◽  
Vol 31 (4-5) ◽  
pp. 411-422 ◽  
Author(s):  
Gísli Már Gíslason ◽  
Jón S. Ólafsson ◽  
Hákon Adalsteinsson
Keyword(s):  
Chemical Properties ◽  
Chemical Parameters ◽  
Invertebrate Fauna ◽  
Glacial Meltwater ◽  
Biological Communities ◽  
Relative Contribution ◽  
Glacial River ◽  
Alpine Rivers ◽  
Physical And Chemical ◽  
And Chemical Properties

The characteristics of stream and river ecosystems in arctic and alpine areas are determined mainly by the relative contribution of glacial meltwater, snowmelt, rainfall and groundwater. Each source generates a particular seasonal hydrological signature, affecting physical and chemical properties, and hence biological communities. The relative contribution of each source is sensitive to climate change. The study was concentrated on the glacial River W-Jökulsá and some non-glacial rivers in the central highlands of Iceland. The water in the glacial river was entirely glacial meltwater at the glacier margin, but the glacial contribution was about 20% 40 km downstream. However, its tributaries and non-glacial reference rivers were mainly springfed. The invertebrate fauna was confined to Chironomidae of the genus Diamesa close to the glacier, but other taxa (species and groups of species) occupied the river further downstream, where their diversity was close to that found in the reference rivers.

Electrochemical Deposition of Polypyrrole Nanostructures for Energy Applications: A Review

2020 ◽  
Vol 16 (4) ◽  
pp. 462-477 ◽  
Author(s):  
Patrizia Bocchetta ◽  
Domenico Frattini ◽  
Miriana Tagliente ◽  
Filippo Selleri
Keyword(s):  
Lithium Batteries ◽  
High Performance ◽  
Relevant Literature ◽  
Chemical Parameters ◽  
Energy Devices ◽  
Energy Applications ◽  
Physico Chemical ◽  
Potential Applications ◽  
Template Free ◽  
Cathodic Polymerization

By collecting and analyzing relevant literature results, we demonstrate that the nanostructuring of polypyrrole (PPy) electrodes is a crucial strategy to achieve high performance and stability in energy devices such as fuel cells, lithium batteries and supercapacitors. In this critic and comprehensive review, we focus the attention on the electrochemical methods for deposition of PPy, nanostructures and potential applications, by analyzing the effect of different physico-chemical parameters, electro-oxidative conditions including template-based or template-free depositions and cathodic polymerization. Diverse interfaces and morphologies of polymer nanodeposits are also discussed.

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