scholarly journals Modified Ethylsilicates as Efficient Innovative Consolidants for Sedimentary Rock

2018 ◽  
Author(s):  
Monika Remzova ◽  
Luis Antonio Martinez Carrascosa ◽  
Maria Jesus Mosquera ◽  
Jiri Rathousky
Keyword(s):  
Size Distribution ◽  
Chemical Properties ◽  
Water Vapor Permeability ◽  
Test Material ◽  
Vapor Permeability ◽  
Surface Layers ◽  
Significant Deterioration ◽  
Stone Monuments ◽  
Physico Chemical ◽  
Natural Characteristics

Even if silicon alkoxides (especially ethylsilicates) have long been used as consolidants of weathered stone monuments, their physical properties are not ideal. In this study, an innovative procedure for the consolidation of sedimentary rocks was developed that combines the use of organometallic and alkylamine catalysts with the addition of well-defined nanoparticles exhibiting a narrow size distribution centered at ca 10 nm. As a suitable test material, the Pietra di Lecce limestone was selected because of its color and problematic physico-chemical properties, such as rather low hardness. Using the developed procedure, the mechanical and surface properties of the limestone were improved without the unwanted over-consolidation of the surface layers of the stone, and any significant deterioration in the pore size distribution, water vapor permeability or the stone’s appearance. The developed modified ethylsilicates penetrated deeper into the pore structure of the stone than the unmodified ones and increased the hardness of the treated material. The formed xerogels within the stone pores did not crack. Importantly, they did not significantly alter the natural characteristics of the stone.

scholarly journals Modified Ethylsilicates as Efficient Innovative Consolidants for Sedimentary Rock

Coatings ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 6 ◽  
Author(s):  
Monika Remzova ◽  
Luis Carrascosa ◽  
María Mosquera ◽  
Jiri Rathousky
Keyword(s):  
Size Distribution ◽  
Chemical Properties ◽  
Water Vapor Permeability ◽  
Test Material ◽  
Vapor Permeability ◽  
Surface Layers ◽  
Significant Deterioration ◽  
Stone Monuments ◽  
Physico Chemical ◽  
Natural Characteristics

Although silicon alkoxides (especially ethylsilicates) have long been used as consolidants of weathered stone monuments, their physical properties are not ideal. In this study, an innovative procedure for the consolidation of sedimentary rocks was developed that combines the use of organometallic and alkylamine catalysts with the addition of well-defined nanoparticles exhibiting a narrow size distribution centered at ca. 10 nm. As a suitable test material, Pietra di Lecce limestone was selected because of its color and problematic physico-chemical properties, such as rather low hardness. Using the developed procedure, the mechanical and surface properties of the limestone were improved without the unwanted over-consolidation of the surface layers of the stone, and any significant deterioration in the pore size distribution, water vapor permeability, or the stone’s appearance. The developed modified ethylsilicates penetrated deeper into the pore structure of the stone than the unmodified ones and increased the hardness of the treated material. The formed xerogels within the stone pores did not crack. Importantly, they did not significantly alter the natural characteristics of the stone.

scholarly journals Evaluation of UV radiation influence on abrasivity of protective-decorative coatings for car bodies

2019 ◽  
Vol 24 (6) ◽  
pp. 192-197
Author(s):  
Danuta Kotnarowska ◽  
Dariusz Stanisławek
Keyword(s):  
Surface Roughness ◽  
Mass Loss ◽  
Uv Radiation ◽  
Ageing Time ◽  
Chemical Properties ◽  
Roughness Parameters ◽  
Surface Layers ◽  
Progressive Decline ◽  
Time Flow ◽  
Physico Chemical

The paper presents investigations concerning physico-chemical properties as well as a resistance to abrasion (abrasivity) of three-layer acrylic-polyester (renovation) coating systems after ageing with ultraviolet (UV) radiation. Generated by UV radiation photodestruction and photodegradation of examined coatings surface layers caused their chipping. This had an impact on progressive decline of the coatings thickness and hardness with the ageing time flow. UV ageing caused also almost twofold increase in surface roughness parameters Ra and Rz values. Surface roughness of the aged coatings increasing with the ageing time flow as well as their decreasing hardness contributed to their resistance to abrasion decrease, measured with the mass loss of abraded (using T-07 apparatus) coating material.

scholarly journals Impact of Resistant Maltodextrin Addition on the Physico-Chemical Properties in Pasteurised Orange Juice

Foods ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1832
Author(s):  
Elías Arilla ◽  
Marta Igual ◽  
Javier Martínez-Monzó ◽  
Pilar Codoñer-Franch ◽  
Purificación García-Segovia
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Orange Juice ◽  
Chemical Properties ◽  
Water Soluble ◽  
Soluble Solids ◽  
Soluble Fibre ◽  
Physico Chemical ◽  
Resistant Maltodextrin

Resistant maltodextrin (RMD) is a water-soluble fibre that can be fermented in the colon and exert prebiotic effects. Therefore, its addition to food and beverage products could be beneficial from both technological and nutritional viewpoints. However, to date, most studies have focused on the stability of the prebiotic fibre rather than its impact in the original food matrices. Therefore, this work aimed to evaluate the addition of RMD on the physico-chemical properties of pasteurised orange juice (with and without pulp). °Brix, pH, acidity, particle size distribution, density, turbidity, rheology, and colour were measured in orange juices with increasing RMD concentrations (2.5, 5, and 7.5%). Control samples without RMD were also prepared. RMD added soluble solids to the orange juice, affecting the °Brix, density, turbidity, and rheology. Slight colour differences were observed, and lower citric acid content was achieved because of orange juice replacement with RMD. Differences in particle size distribution were exclusively because of pulp content. Further studies are needed to elucidate if potential consumers will appreciate such physico-chemical changes in organoleptic terms.

scholarly journals Physical-Chemical Properties of Edible Film Made from Soybean Residue and Citric Acid

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Wenjun Ma ◽  
Sami Rokayya ◽  
Liang Xu ◽  
Xiaonan Sui ◽  
Lianzhou Jiang ◽  
...  
Keyword(s):  
Citric Acid ◽  
Food Packaging ◽  
Chemical Properties ◽  
Water Vapor Permeability ◽  
Edible Films ◽  
Edible Film ◽  
Sodium Hypophosphite ◽  
Vapor Permeability ◽  
Physical Chemical ◽  
Aqueous Extraction Processing

The effect of citric acid on the properties of soybean enzyme-assisted aqueous extraction processing (EAEP) residue edible film was studied. The washed soybean EAEP residue was produced by the process of EAEP. It was determined that the washed soybean EAEP residue is rich in fibers (76.10 ± 1.03%) and has lower oil and protein contents (7.74 ± 0.11% and 3.50 ± 0.20%, resp.). Edible films intended for food packaging have been produced from the washed EAEP residue combined with glycerol, different concentrations of citric acid (0%, 10%, 15%, 20%, 25%, and 30%), and sodium hypophosphite. The spectra have evidenced that the cross-linking reaction of citric acid and fibers has taken place in the residue. 30-CA films showed the highest tensile strength (17.52 MPa) and the lowest water vapor permeability (7.21 g·cm−1·s−1·Pa−1). Also, it indicated that citric acid can cross-link with the hydroxyls of polysaccharide and improve the compatibilization between the polymeric molecules to improve the intermolecular interaction between polysaccharide molecules, so that the water uptake is reduced. The smooth surface and better translucency of the films suggest that the EAEP residue films treated with citric acid are suitable for application in food packaging.

Nano Structure and Properties of Beta–D-Poly-Glucopyranose

2010 ◽  
Vol 123-125 ◽  
pp. 739-742
Author(s):  
Oleg Figovsky ◽  
Michael Ioelovich
Keyword(s):  
Phase Transformation ◽  
Structural Characteristics ◽  
Chemical Properties ◽  
Supermolecular Structure ◽  
Structure And Properties ◽  
Surface Layers ◽  
Nano Structure ◽  
Nano Scale ◽  
Physico Chemical ◽  
Multi Level

Beta–D-poly-glucopyranose is widespread class of the natural semi-crystalline polysaccharide known as cellulose. This polymer has complicated multi-level supermolecular structure. It is built from elementary nano-fibrils and their aggregates; moreover, each nano-fibril contains ordered nanocrystallites and low-ordered amorphous nano-domains. Therefore cellulose can be a pronounced and eminent representative of nano-structured matters. Such nano matter has peculiar physico-chemical properties depending on specific surface of nano-scale constituents. In this paper, physico-chemistry of the nano-structured cellulose is discussed. In particular, the ability of nano-scale crystallites to co-crystallization and aggregation, as well as their ability to phase transformation through dissolution, alkalization and chemical modification was a subject of the investigation. Structural characteristics of paracrystalline surface layers of nano-crystallites and their effect on physico-chemical properties of the polysaccharide have been discussed.

scholarly journals Comparative effectiveness of intra-articular administration of different drugs of hyaluronic acid with various physico-chemical properties in knee osteoarthritis

2021 ◽  
Vol 15 (6) ◽  
pp. 48-54
Author(s):  
E. A. Belyaeva ◽  
A. S. Fatenko ◽  
O. S. Avdeeva ◽  
S. V. Belyaeva
Keyword(s):  
Hyaluronic Acid ◽  
Knee Osteoarthritis ◽  
Randomized Study ◽  
Chemical Properties ◽  
Subjective Assessment ◽  
Serious Adverse Events ◽  
Significant Deterioration ◽  
Important Place ◽  
Womac Index ◽  
Physico Chemical

Knee osteoarthritis (KOA) is a chronic disease that leads to a significant deterioration in the quality of life and disability. In the treatment of OA, hyaluronic acid (HA) drugs have an important place.Objective: to compare the effectiveness of ROA treatment with different HA drugs with different physicochemical properties and molecular weight.Patients and methods. A 12-week prospective randomized study of the comparative efficacy of a single intra-articular injection of three HA drugs – Armaviscon Forte (AF), Flexotron Cross (FCr) and Flexotron Ultra (FUL) was carried out. The study group consisted of 90 patients with knee osteoarthritis, aged from 43 to 50 years (the majority were women – 63.3%) with an initial severity of pain >40 mm according to the visual analogue scale (VAS). The result of therapy was assessed by the dynamics of pain (VAS), WOMAC index, and subjective assessment of the effect 3 months after intra-articular administration of HA.Results and discussion. Eight patients dropped out of the study: in the AF group – 3, FCr – 4, FUL – 1. After 90 days, the decrease in pain compared to baseline values in the AF group was 30%, in FCr – 46% and in FUL – 57% (p ≤0,05), and the dynamics of the WOMAC index – 27, 36, and 42%, respectively. After 90 days, 85.0, 93.4 and 96.5% of patients noted improvement and significant improvement in the AF, FCr and FUL groups, respectively. No serious adverse events were recorded.Conclusion. All investigated drugs demonstrated high analgesic potential, but the best clinical effect was observed with FUL.

scholarly journals Influence of fire on selected physico-chemical properties of forest soil

2019 ◽  
Vol 70 (1) ◽  
pp. 39-43
Author(s):  
Małgorzata Majder-łopatka ◽  
Wiesław Szulc ◽  
Beata Rutkowska ◽  
Dominik Ptasiński ◽  
Witold Kazberuk
Keyword(s):  
Organic Carbon ◽  
Chemical Properties ◽  
Test Material ◽  
Soil Profiles ◽  
Exchangeable Acidity ◽  
Physico Chemical ◽  
Negative Effect ◽  
Physical And Chemical ◽  
Nitrogen Contents ◽  
And Chemical Properties

Abstract The aim of the research was to determine whether, and to what extent, a surface fire of forest areas determines changes in physical and chemical properties of the soil. The test material consisted of soil samples taken from soil profiles exposed in a burnt-out area and in an area unaffected by fire. The samples were analyzed for total organic carbon and total nitrogen contents, and also selected indicators of soil acidification. As a result of the tests, it was found that there was a decrease in the levels of organic carbon (by over 75%) and nitrogen (by 50%). A negative effect of the changes was the narrowing of the C/N ratio, a positive one – an increase in soil pH (from 3.14 to 4.67), and a several-times reduction in hydrolytic and exchangeable acidity.

Variability of enzymatic activity in forest Cambisols and Brunic Arenosols of Polish lowland areas

2013 ◽  
Vol 64 (2) ◽  
pp. 54-59 ◽  
Author(s):  
Ewa Błońska ◽  
Jarosław Lasota ◽  
Kazimierz Januszek
Keyword(s):  
Enzymatic Activity ◽  
National Parks ◽  
Chemical Properties ◽  
Soil Surface ◽  
Surface Layers ◽  
Physico Chemical ◽  
Lowland Area ◽  
The Relationship ◽  
Properties Of Soil ◽  
Humus Horizons

Abstract The aim of this study was to determine the enzymatic activity (dehydrogenase and urease) in trophically diverse Brunic Arenosols and Cambisols. Efforts to establish the relationship between enzymatic activity and physico-chemical properties of various subtypes of Brunic Arenosols and Cambisols were attempted. Another aim was to determine the effect of vegetation on the properties of soil surface levels. The study was conducted on 94 plots located in nature reserves and national parks in the Polish lowland area. Dehydrogenase activity and urease showed large variations in the subtypes of the distinguished Brunic Arenosols and Cambisols. Dehydrogenases and urease activity in surface layers of fresh humus of Cambisols and Brunic Arenosols was strongly associated with the plants. This is confirmed by the relationship between the enzymatic activity and the type of accumulated humus substances, the ratio of carbon to nitrogen and humus horizons reaction.

Preparation and Assessment of Superhydrophobic Organic-Inorganic Hybrid Coatings for Conservation of Yungang Grottoes

2011 ◽  
Vol 1319 ◽  
Author(s):  
Shipeng Tian ◽  
Shaojun Liu ◽  
Feng Gao ◽  
Min Fan ◽  
Jianguang Ren
Keyword(s):  
Water Vapor Permeability ◽  
Contact Angles ◽  
Hybrid Coatings ◽  
Vapor Permeability ◽  
Protection Efficiency ◽  
Inorganic Hybrid ◽  
Stone Monuments ◽  
Salt Corrosion ◽  
World Cultural Heritage ◽  
Yungang Grottoes

ABSTRACTYungang Grottoes in Shanxi, China, which represent outstanding example of Chinese outdoor immovable stone artifacts, are precious world cultural heritage. In the present study, the preparation and assessment of superhydrophobic hybrid coatings with photocatalytic activity on the sandstone substrate collected from Yungang were explored preliminarily. The protection efficiency of coating is investigated by measuring the water-stone contact angles, water vapor permeability, water absorption, and resistance to acid and salt corrosion. Results show that the superhydrophobic organic-inorganic hybrid coatings with photocatalytic and self-cleaning properties are highly suitable for the conservation of stone monuments.

scholarly journals Quality Assessment of Shoe Leather Based on the Properties of Strength and Comfort, Collected from Different Footwear and Leather Industries in Bangladesh

2020 ◽  
Author(s):  
Md. Delwar Hossain ◽  
◽  
Forhad Ahammed Bin Azam ◽  
Manjushree Chowdhury ◽  
◽  
...  
Keyword(s):  
Chemical Properties ◽  
Water Vapor Permeability ◽  
Rejection Rate ◽  
Vapor Permeability ◽  
Oxide Content ◽  
International Union ◽  
Different Types ◽  
Physical And Chemical ◽  
And Chemical Properties

Based on the environmental condition, a shoe manufactured with different suitable materials has to provide optimum comfort and strength features by using high-quality leather parts. The aim of the study is to evaluate the quality of the shoe upper leather in Bangladesh. Ten different types of shoe leather, made from cow hides and goat skins, were collected from different footwear and leather industries in Bangladesh. The research was carried out by using approved methods of analysis as per the International Union of the Society of Leather Technologists and Chemists’ official methods for physical and chemical analysis. Physical and chemical properties, which were studied three times for each of the samples, were tensile strength, percentage of elongation, tearing strength, grain crack resistance, water vapor permeability, flexing endurance, scuff resistance, perspiration fastness, color rub fastness, bond strength of the finish film, the pH, moisture content, chromic oxide content and fat content, respectively. From the study, it has been revealed that samples 02 and 08 were completely unacceptable, samples 04, 05 and 07 were moderately acceptable, and the remaining samples, 01, 03, 06, 09 and 10, were strongly acceptable on the basis of the ISO standard for shoe leather. To get the better quality, the above mentioned tests should be improved, thus the demand and the value of shoe leather, as well as footwear, will be increased and the rejection rate will be decreased gradually.

Sign in / Sign up

Export Citation Format

Share Document