Analysis of the chemical composition of dust particles in the warehouse of building materials

Introduction. The development of the construction industry is accompanied by the use of new technologies and building materials. Materials based on mineral wool (MW) became to be widely used. The article presents the results of the study of working environment factors and the determination of the safe for health work experience based on the health risk calculation for workers in contact with MW. Material and methods. To quantify the air pollution of the working area at the construction site, samples were taken using an aspirator and a dust meter. An absorption method using a spectrophotometer was used to determine the chemical composition of the dust. Statistical analysis and mathematical modeling were carried out using a standard software package Microsoft Excel, STADIA. Results. A table for the rapid health risk assessment of workers in contact with MW was developed. The risk of health loss is determined as “High” (R = 11.3). Discussion. Working conditions under the performance of heat-insulating works at facades cladding with the use of MW are classified as harmful (class 3.2) on the dust content in working zone air. In the course of the study, coarse dust and fine dust were found in the air. The data on the change of the dust concentration depending on air humidity, the concentration of dust particles of different dispersion at different distances from the place of work is presented. The chemical composition of dust is presented, the presence of heavy metals is established. Dependences for the determination of safe for health work experience under the influence of the various concentration of dust and the duration of contact are constructed. Сonclusions. On the basis of the research to improve the legal support in the field of occupational health and safety, a number of activities for workers engaged in work with the use of MW are proposed.

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The Research of Iron Containing Wastes Modification Process of Leninabad Rare Metals Plant

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.410.778 ◽

2021 ◽

Vol 410 ◽

pp. 778-783

Author(s):

Pavel V. Matyukhin ◽

Daler I. Mirzoev

Keyword(s):

Chemical Composition ◽

Building Materials ◽

Raw Material ◽

Filling Material ◽

Rare Metals ◽

X Ray ◽

Modification Process ◽

Before And After ◽

The Republic ◽

Enrichment Process

The paper presents the results of ferriferous wastes modification process research carried on the basis of JCS “Leninobad rare metals Plant” located in the Republic of Tajikistan. The wastes for the study were taken from the western tailing. The article presents the justification of the chosen wastes as a filling material in the development of new radiation protective composite building materials. The data on the initial ferriferous chemical composition of the tailing wastes and the chemical composition of the material that passed the enrichment process is presented. The study contains microphotos of ferriferous haematite raw material particles surface before and after completing the modifying process. The paper presents and describes the study of X-ray phase analysis diffractograms of enriched iron-containing wastes before and after the modification process. The current research proves that the enrichment ferriferous wastes particles modification process is possible and as a result it can be used as a filling for the development of new kinds of radioprotective composite materials.

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Interfacial interactions between urea formaldehyde and cellulose nanofibrils (CNFs) of varying chemical composition and their impact on particle boards manufacture (PBs)

10.21203/rs.3.rs-315097/v1 ◽

2021 ◽

Author(s):

Maria C. Iglesias ◽

Philip S. McMichael ◽

Osei A. Asafu-Adjaye ◽

Brian K. Via ◽

Maria S. Peresin

Keyword(s):

Chemical Composition ◽

Building Materials ◽

Colloidal Stability ◽

Low Cost ◽

Urea Formaldehyde ◽

Cellulose Nanofibrils ◽

Global Market ◽

Modulus Of Rupture ◽

Superior Performance ◽

Interfacial Interactions

Abstract Wood-based panels are commonly used as building materials for interior and exterior purposes. Their production and utilization have increased over the past decades due to the useful properties they present. Adhesive-bonded products make up to 80% of the wood alternatives on the global market, and of that, urea-formaldehyde (UF) makes up approximately 81% of the resins used. Formaldehyde-based resins are used due to their effectiveness and low cost, as well as their ease of application and lack of color. Nevertheless, their main disadvantages are the lack of tackiness and the emission of formaldehyde over time. To improve UF performance, the utilization of microfibrillated cellulose, has been demonstrated to be effective. However, more understanding on the mechanisms of the interactions is of relevant importance. In this work, we studied interfacial interactions between UF with bleached (BCNF) and unbleached (LCNF) cellulose nanofibrils using Quartz Crystal Microbalance with dissipation monitoring (QCM-D) technique observing the superior performance of lignin-containing CNF. Additionally, the surface free energies were investigated using Contact Angle Measurements (CA) showing a decrease of the values mainly when utilizing LCNF, which was later correlated with the wettability properties of the particle boards (PBs). PBs with different adhesive/CNF formulations were produced showing larger improvements when adding LCNF in terms of modulus of elasticity (MOE), modulus of rupture (MOR), and internal bonding (IB). To gain a better understanding on the interactions between CNF and UF, CNF was fully characterized in terms of morphology, chemical composition, charge density, as well as thermal and colloidal stability.

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Bayern`s Method of Al2O3 Production – Possibilities of Red Mud Disposal and Utilization

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.176.11 ◽

2011 ◽

Vol 176 ◽

pp. 11-20 ◽

Cited By ~ 1

Author(s):

Mariola Saternus

Keyword(s):

Chemical Composition ◽

Red Mud ◽

Building Materials ◽

Short Description ◽

Iron Recovery ◽

Alumina Production ◽

Advantages And Disadvantages ◽

Primary Aluminium

Bayern`s method is the first stage of obtaining primary aluminium. The product of this process is alumina. The paper presents how much alumina was produced in the last couple of years and who were its leading producers. As the main ore for alumina production is bauxite; it was necessary to describe its characteristics: chemical composition and types of bauxites. Short description of the method (digestion, precipitation and calcination) was presented. During this process a lot of pollution is usually emitted to the atmosphere, but mostly a lot of red mud is generated. This is the main waste of the process, which at the same time is very harmful to the environment. The ways red mud is disposed or utilized were reviewed. Two kinds of red mud disposal are known: wet and dry disposal. Both were characterized and their advantages and disadvantages were outlined. The possibilities of red mud utilization were shown. The focus was put on iron recovery or recovery of compounds such as Al2O3 or TiO2. The use of red mud in building materials was discussed. Radioactivity of such materials was also analyzed. Possibility of red mud utilization as a pigment and radiopaque material was also mentioned.

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Physical Properties of the Interplanetary Dust

International Astronomical Union Colloquium ◽

10.1017/s0252921100089211 ◽

1971 ◽

Vol 12 ◽

pp. 377-388

Author(s):

Martha S. Hanner

Keyword(s):

Optical Properties ◽

Spatial Distribution ◽

Chemical Composition ◽

Physical Properties ◽

Physical Nature ◽

Interplanetary Dust ◽

Physical Structure ◽

Dust Particles ◽

Cometary Material ◽

Direct Condensation

The interplanetary dust may be composed of cometary material, interstellar grains, debris from asteroidal collisions, primordial material formed by direct condensation, or contributions from all of these sources. Before we can determine the origin of the dust, we need to know its physical nature, spatial distribution, and the dynamical forces that act on the particles. The spatial distribution and dynamics are separately treated in this symposium by Roosen. We discuss here the physical characteristics of the dust particles: their size distribution, chemical composition, physical structure, and optical properties.

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Flammability of the Disperse-Filled Polymer Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.871.40 ◽

2016 ◽

Vol 871 ◽

pp. 40-46 ◽

Cited By ~ 3

Author(s):

Andrey Askadsky ◽

Valentin Ushkov ◽

Vladimir Smirnov ◽

Viktor Voronin

Keyword(s):

Experimental Data ◽

Chemical Composition ◽

Specific Heat ◽

Main Parameter ◽

Building Materials ◽

Oxygen Index ◽

Limiting Oxygen Index ◽

Polymer Binders ◽

Mineral Fillers ◽

Epoxy Matrices

For the purpose of fire safe construction it is necessary to develop and investigate effects of fillers to flammability of building materials, including composite materials with polymer matrix. In present work we demonstrate the results of such investigation. We have examined influence of chemical composition, amount of mineral fillers to flammability, smoke-forming ability and limiting oxygen index of building materials based on different polymer binders. The experimental data indicate that the main parameter which determines the influence of mineral fillers on the flammability of composites is a specific heat absorbed by the filler. The dependence between limiting oxygen index and specific heat of mineral fillers is revealed for composites with epoxy matrices. This dependence is simple and beneficial for practical use.

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The Role of Expansion and Fragmentation Phenomena on the Generation and Chemical Composition of Dust Particles in a Flash Converting Reactor

Metallurgical and Materials Transactions B ◽

10.1007/s11663-016-0758-y ◽

2016 ◽

Vol 47 (5) ◽

pp. 3115-3125 ◽

Cited By ~ 2

Author(s):

Cirilo Andrés Duarte-Ruiz ◽

Manuel Pérez-Tello ◽

Víctor Roberto Parra-Sánchez ◽

Hong Yong Sohn

Keyword(s):

Chemical Composition ◽

Dust Particles ◽

Flash Converting

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Research of filter materials for dust fractioning

E3S Web of Conferences ◽

10.1051/e3sconf/202128405011 ◽

2021 ◽

Vol 284 ◽

pp. 05011

Author(s):

Vladimir Dmitrienko ◽

Stanislav Мaslennikov ◽

Аleksandr Bogomzov

Keyword(s):

Building Materials ◽

Measurement Accuracy ◽

Gravimetric Method ◽

Microscopic Analysis ◽

Dust Particles ◽

Dust Formation ◽

Dust Emissions ◽

Specific Location ◽

Filter Materials ◽

Blower Performance

A special place in air pollution with dust emissions is occupied by the production of building materials, using large quantities of dispersed mineral substances as aggregates. The article is devoted to the study of hazardous dust fractions emission when assessing the dustiness of the working area for the production of concrete and reinforced concrete products, since the specific location and operation of the equipment complex is characterized by uneven dust formation in space and time. This reduces the efficiency of the aspiration systems. Based on the analysis of methods and means for assessing dustiness, the use of the gravimetric method is justified, however, to assess the content of the most dangerous dust particles for the human body with a size of 2.5 to 10 microns, a size separation of particles is required. Non-woven synthetic filter materials of various thick-nesses and densities are investigated. It is proposed to carry out sampling in blocks with three filters from different filter materials. The studies were carried out with the help of a specially made portable complex. The most effective filter materials were determined with the help of microscopic analysis. The conducted calibration of the blower performance with an assessment of the measurement accuracy showed relatively small errors in the air sampling, which confirms the feasibility of assessing the dustiness of the filter blocks.

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The COSMIC DUST ANALYZER for the CASSINI Mission to Saturn

International Astronomical Union Colloquium ◽

10.1017/s0252921100501596 ◽

1996 ◽

Vol 150 ◽

pp. 227-231 ◽

Cited By ~ 2

Author(s):

R. Srama ◽

E. Grün ◽

Keyword(s):

Chemical Composition ◽

Mass Spectrometer ◽

Electric Charge ◽

Impact Ionization ◽

Cosmic Dust ◽

Dust Particles ◽

Sensitive Area ◽

Induction Principle ◽

Cassini Mission ◽

Saturnian System

AbstractIn October 1997 a unique mission to the Saturnian system will be launched by NASA, the CASSINI mission. One goal of this mission is to study the Saturnian dust environment, and for this task, the COSMIC DUST ANALYZER (CDA) has been developed and is currently being tested. Impact ionization is used to determine the speed (1 - 100 km/s) and the mass (1•10–15 – 1•10–9 g) of impinging particles. Furthermore, the electric charge (1•10–15 – 1•10–12 C) of the particles can be measured via the induction principle, and an integrated time-of-flight mass spectrometer will analyze the chemical composition of individual dust particles. In order to achieve sufficient sensitivity for dust fluxes as low as 10 particles/(month-m2), the sensor has a large sensitive area of 0.1 m2. This paper will describe the function of the experiment.

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The solar abundance problem and eMSTOs in clusters

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936932 ◽

2020 ◽

Vol 641 ◽

pp. A73

Author(s):

Richard Hoppe ◽

Maria Bergemann ◽

Bertram Bitsch ◽

Aldo Serenelli

Keyword(s):

Chemical Composition ◽

Stellar Evolution ◽

Open Clusters ◽

Dust Particles ◽

Convective Envelope ◽

Physical Conditions ◽

Relevant Effect ◽

Standard Scenario ◽

The Impact ◽

Protoplanetary Discs

In this study, we focus on the impact of accretion from protoplanetary discs on the stellar evolution of AFG-type stars. We used a simplified disc model that was computed using the Two-Pop-Py code, which contains the growth and drift of dust particles in the protoplanetary disc, to model the accretion scenarios for a range of physical conditions for protoplanetary discs. Two limiting cases were combined with the evolution of stellar convective envelopes that were computed using the Garstec stellar evolution code. We find that the accretion of metal-poor (gas) or metal-rich (dust) material has a significant impact on the chemical composition of the stellar convective envelope. As a consequence, the evolutionary track of the star diverts from the standard scenario predicted by canonical stellar evolution models, which assume a constant and homogeneous chemical composition after the assembly of the star is complete. In the case of the Sun, we find a modest impact on the solar chemical composition. Indeed, the accretion of metal-poor material reduces the overall metallicity of the solar atmosphere and it is consistent, within the uncertainty, with the solar Z reported by Caffau et al. (2011, Sol. Phys., 268, 255), but our model is not consistent with the measurement by Asplund et al. (2009, ARA&A, 47, 481). Another relevant effect is the change of the position of the star in the colour-magnitude diagram. By comparing our predictions with a set of open clusters from the Gaia DR2, we show that it is possible to produce a scatter close to the TO of young clusters that could contribute to explaining the observed scatter in CMDs. Detailed measurements of metallicities and abundances in the nearby open clusters will additionally provide a stringent observational test for our proposed scenario.

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