Formation of Efflorescence on the Surface of Construction Products in the Process of their Operation

2015 ◽  
Vol 1122 ◽  
pp. 39-43 ◽  
Author(s):  
Grigory Yakovlev ◽  
Alena Politaeva ◽  
Arina Shaybadullina ◽  
Anastasiia Gordina ◽  
Alexander Buryanov
Keyword(s):  
Carbon Dioxide ◽  
Calcium Hydroxide ◽  
Construction Materials ◽  
Chemical Compounds ◽  
Building Structure ◽  
Factors Influencing ◽  
Construction Products ◽  
Second Year

The factors influencing the formation of efflorescence of construction materials are connected with the increased solubility of the ingredients of construction materials. Efflorescence may accumulate under some less permeable decorative paint layers and cause their peeling from the surface of a building structure, its decorative properties being completely lost. At the same time, the formation of efflorescence not only as white bloom, but also as "blooming" of the surfaces of materials due to the formation of new chemical compounds is possible. Similar processes occur in the process of operation of coloured pavers manufactured wth vibrocompression of cement and sand mortars with the addition of colouring pigments. The main source of efflorescence is calcium hydroxide Ca (OH)2 which is formed in hardening cement. The alkaline nature leads to its intensive interaction with carbon dioxide CO2. This efflorescence in the second year of operation, as a rule, does not resume due to the carbonation of calcium hydroxide in the structure of set cement.

The Chemistry Decomposition in Human Corpses

2017 ◽  
Vol 68 (6) ◽  
pp. 1352-1356 ◽  
Author(s):  
Beatrice Gabriela Ioan ◽  
Cristiana Manea ◽  
Bianca Hanganu ◽  
Laura Statescu ◽  
Laura Gheuca Solovastru ◽  
...  
Keyword(s):  
Chemical Compounds ◽  
Human Remains ◽  
Organic Substances ◽  
Chemical Decomposition ◽  
Factors Influencing ◽  
Human Decomposition ◽  
Decomposition Processes ◽  
Human Cadavers ◽  
The Subject ◽  
Decomposition Stages

Human body is a complex of organic substances (proteins, lipids, carbohydrates), which undergo chemical decomposition processes soon after death. The compounds released during decomposition characterize the development of different stages of this process: e.g. biogenic amines resulted from the proteins decomposition will confer the particular smell of a cadaver, gases resulted from carbohydrates fermentation will give the bloating aspect of the cadaver. The study of cadaver decomposition and the products resulted from this process is the subject of human taphonomy and is realized nowadays in special facilities in USA and Australia. Identification and analysis of the chemical compounds emerged after human decomposition (gases, liquids, salts) give valuable information to forensic pathologists for estimating the postmortem interval (PMI). More, volatile compounds � which give the odor signature�specific to human remains � may be utilized in identifying clandestine burials, human remains or victims entrapped under ruins in cases of natural disasters. In this paper the authors describe the chemical decomposition stages of human cadavers, the factors influencing these processes and utility for the forensic activity of the results of human taphonomic studies.

Controlled preparation of micro–nano hierarchical hollow calcium carbonate microspheres by pressurized-CO2 carbonization and their CaCO3:Eu3+ photoluminescence properties

CrystEngComm ◽  
2021 ◽  
Vol 23 (16) ◽  
pp. 3033-3042
Author(s):  
Liubin Shi ◽  
Mingde Tang ◽  
Yaseen Muhammad ◽  
Yong Tang ◽  
Lulu He ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Calcium Carbonate ◽  
Calcium Hydroxide ◽  
Hierarchical Structure ◽  
Ethylenediaminetetraacetic Acid ◽  
Disodium Salt ◽  
Hollow Microspheres ◽  
Photoluminescence Properties ◽  
Controlled Preparation

Herein, calcium carbonate hollow microspheres with a micro–nano hierarchical structure were successfully synthesized using disodium salt of ethylenediaminetetraacetic acid (EDTA-2Na) as an additive, by bubbling pressurized carbon dioxide and calcium hydroxide at 120 °C.

675. The carbon dioxide content of New Zealand Cheddar cheese

1957 ◽  
Vol 24 (2) ◽  
pp. 235-241 ◽  
Author(s):  
P. S. Robertson
Keyword(s):  
Carbon Dioxide ◽  
New Zealand ◽  
Carbon Dioxide Concentration ◽  
Cheddar Cheese ◽  
Carbon Dioxide Content ◽  
Single Strain ◽  
Open Texture ◽  
Factors Influencing ◽  
High Concentrations ◽  
Lower Temperature

Some of the factors influencing the concentration of carbon dioxide found in New Zealand Cheddar cheese have been investigated.1. Cheeses made with the use of commercial starters (containing betacocci) are characterized by a rapid increase in their carbon dioxide content during the 2 weeks following manufacture.2. Cheeses made with the use of single strain starters do not change in carbon dioxide content in the first 2 weeks following manufacture, but may ultimately contain as much carbon dioxide as commercial starter cheeses.3. High concentrations of carbon dioxide within a cheese result in an open texture, especially when the carbon dioxide is formed shortly after manufacture.4. The loss of carbon dioxide to the atmosphere is demonstrated by the existence of a carbon dioxide concentration gradient within the cheese.5. Storage of cheese at a lower temperature than is usual results in retarded carbon dioxide formation.

Factors influencing visible ozone injury on potato including the interaction with carbon dioxide

2002 ◽  
Vol 17 (4) ◽  
pp. 291-302 ◽  
Author(s):  
L De Temmerman ◽  
G.Pihl Karlsson ◽  
A Donnelly ◽  
K Ojanperä ◽  
H.-J Jäger ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Ozone Injury ◽  
Factors Influencing

Container System Design Developments Over Two Decades

1982 ◽  
Vol 19 (04) ◽  
pp. 364-376
Author(s):  
L. A. Harlander
Keyword(s):  
System Design ◽  
Construction Materials ◽  
Common Denominator ◽  
Strength Criteria ◽  
The Past ◽  
Factors Influencing ◽  
Design Loads ◽  
Speed Stability ◽  
The Common ◽  
Gantry Cranes

This paper reviews the progress made over the past 20 years in the design and handling of containers. Factors influencing present container dimensions and strength criteria are discussed, as well as the crucial activity to establish container standardization. The container itself—"the common denominator"—is addressed from the viewpoint of its fittings, design loads and construction materials; and the containership from the viewpoint of arrangements, size, speed, stability, stowage and economics. The author offers several conclusions following the last two sections of the paper, which cover the remaining components of the system, namely, the shoreside gantry cranes and terminal facilities.

scholarly journals Hazards Resulting from the Burning Wood Impregnated with Selected Chemical Compounds

2020 ◽  
Vol 10 (17) ◽  
pp. 6093
Author(s):  
Anna Rabajczyk ◽  
Maria Zielecka ◽  
Daniel Małozięć
Keyword(s):  
Heavy Metals ◽  
Construction Industry ◽  
Large Range ◽  
Construction Materials ◽  
Chemical Compounds ◽  
Waste Incineration ◽  
The Other ◽  
Performance Parameters ◽  
Knowledge Use ◽  
Wooden Products

In the construction industry, a variety wooden products have been used for thousands of years, according to demand, accessibility/availability, and customers’ requirements. Wood is a preferred material due to its large range of properties, depending on the type of wood. It is an easily available and economically competitive material, and it is also extremely strong in relation to its weight. Therefore, it is used in the production of construction materials, building parts, and finishing components, as well as for furniture and decorative elements. Each of these products is commonly additionally chemically treated in order to improve its performance parameters. However, impregnated wooden products such as furniture and fence boards are often misused, including for house heating, waste incineration, bonfires, etc. For this reason, among the products of combustion, there is a whole range of different chemical compounds, frequently carcinogenic, and dangerous for health and the environment, for example, heavy metals. Knowledge in this field is important for professions, such as: firefighter, lifeguard, people dealing with environmental management, and units responsible for waste landfills. On the other hand, important recipients of this information are ordinary residents who, due to a lack of knowledge, use such materials as e.g., heating material.

Delayed Hardening and Reactivation of Binder Calcite, Common Problems in Radiocarbon Dating of Lime Mortars

Radiocarbon ◽  
2020 ◽  
Vol 62 (3) ◽  
pp. 565-577 ◽  
Author(s):  
Alf Lindroos ◽  
Åsa Ringbom ◽  
Jan Heinemeier ◽  
Irka Hajdas ◽  
Jesper Olsen
Keyword(s):  
Carbon Dioxide ◽  
Phosphoric Acid ◽  
Calcium Hydroxide ◽  
Radiocarbon Dating ◽  
Lime Mortars ◽  
Dating Method ◽  
Common Problems

ABSTRACTWhen sampling mortars for radiocarbon (14C) dating it is crucial to ensure that the sample has hardened rapidly relative the resolution of the dating method. Soft and porous lime mortars usually fulfill this criterion if the samples are taken from an uncovered surface from less than a few centimeters deep. However, hard, concrete-like mortars may be impermeable for carbon dioxide and even the outermost centimeters may still contain uncarbonated calcium hydroxide. These mortars may harden very slowly and contain carbonate that formed centuries or even millennia after the original building phase, and they can still be alkaline and capture modern 14C, causing younger 14C ages than the actual construction age. Another problem is reactivation of the binder carbonate if it has been partly decarbonated during a fire later on in its history. It will be shown that these young carbonates dissolve rapidly in phosphoric acid and in many cases a reasonable 14C age can be read from 14C profiles in sequential dissolution if the measurements from initially formed carbon dioxide are disregarded. However, if a mortar was made waterproof deliberately by adding crushed or ground tile, as in Roman cocciopesto mortars, it may be very difficult to get a conclusive dating.

scholarly journals Sequestration of carbon dioxide into building products based on the dolomite binder of carbonate hardening

2019 ◽  
Vol 97 ◽  
pp. 02024 ◽  
Author(s):  
Tamara Bakhtina ◽  
Nikolay Lyubomirskiy ◽  
Aleksandr Bakhtin
Keyword(s):  
Carbon Dioxide ◽  
Building Materials ◽  
Mechanical Parameters ◽  
Building Products ◽  
Construction Products ◽  
Extractive Substances ◽  
Cement Binder ◽  
Additional Exposure

The paper covers the method of obtaining efficient structural heat-insulating and heat-insulating construction products based on sawdust and lime binder hardening in the medium of carbon dioxide. Building composites based on wood-cement compositions have several advantages compared to traditional concrete products, but at the same time there are several features such as incompatibility of cement binder with a certain type of wood due to the release of extractive substances by the wood and retardation of the binder which complicate the receiving technology. The use of a binder that was not affected by extractives, such as dolomite carbonate binder, greatly simplifies the production of finished products. Performed researches have shown the possibility of obtaining light building materials based on sawdust and lime binder of carbonate hardening. The process of obtaining samples in a specially designed mold takes 4-8 minutes; after that the samples achieve the required characteristics. The samples extracted from the mold do not require additional exposure and have specified geometrical and physico-mechanical parameters.

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