Dust Powder Research Articles

Respiratory health of workers exposed to polyacrylate dust.

Background:Polyacrylate (PA) powder dust formed in PA manufacturing units is fine sized, i.e., in nanosize. Although several previous studies reported possible significant adverse effects of nanomaterials, studies on the harmful effect of small-sized PA particles on the respiratory health of the workers are scarce. The present study was carried out to assess the effect of PA on respiratory health and lung volumes/rates among the workers of PA manufacturing unit.Materials and Methods:The present cross-sectional study included 84 workers of PA manufacturing unit. Using interview technique as a tool for data collection, demographic, occupational, and clinical details of the workers were recorded on the predesigned pro forma. This was followed by detailed clinical examination, spirometry, chest X-ray (posteroanterior [PA] view), and high-resolution computed tomography (HRCT) examination of each worker.Results:On the basis of clinical examination, chest radiography, and HRCT, 17.9% of the workers were found to have fibrotic and cavitarychanges in lung parenchyma. The production department workers had a higher proportion of respiratory morbidities as compared to supervisory or office staff. Age, gender, smoking habit, and duration of exposure were nonsignificant risk factors for respiratory morbidity. The overall mean forced vital capacity, forced expiratory volume in 1sts, Peak Expiratory Flow Rate (PEFR), (Maximal Mid Expiratory Flow Rate) MMEFR0.2–1.2, and MMEFR25%–75% were 3.19 ± 0.77 L, 2.72 ± 0.67 L, 6.82 ± 1.86 L/s, 5.79 ± 2.03 L/s, and 3.16 ± 1.19 L/s, respectively. Females and those having respiratory morbidity had significantly lower values of all spirometric parameters as compared to their counterparts.Conclusions:The workers exposed to engineered fine dust of PA may be at risk of respiratory ill-health.

Evaluation of the Effects of Filler Fineness on the Properties of an Epoxy Asphalt Mixture.

The type and fineness of a filler significantly affect the performance of an asphalt mixture. There is a lack of specific research on the effects of filler fineness and dust from aggregates on the properties of epoxy asphalt (EA) mixtures. The effects of aggregate dust and mineral powder on the properties of an EA mixture were evaluated. These filler were tested to determine their fineness, specific surface area and mineral composition. The effects of these fillers on the EA mastic sample and mixture were evaluated. The morphology of the EA mastic samples was analyzed using scanning electron microscopy (SEM). The effects of the fillers on the Marshall stability, tensile strength and fatigue performance of the EA mixture were evaluated. The dust from the aggregates exhibited an even particle size distribution, and its average particle size was approximately 20% of that of the mineral powder. The SEM microanalysis showed that the EA mastic sample containing relatively fine dust formed a tight and dense interfacial bonding structure with the aggregate. The EA mixture sample containing filler composed of dust from aggregate had a significantly higher strength and longer fatigue life than that of the EA sample containing filler composed of mineral powder.

A Study on The Fully Enclosed Housing Of Interior Permanent Magnet Synchronous Motor

Approximately 2.5 billion won can be saved every year by replacing existing induction motors, which are traction motors for urban railway vehicles, with permanent magnet motors. This paper presents a study on the structural design of a completely enclosed motor to commercialize an interior permanent-magnet synchronous motor (IPMSM) for the traction of urban railway vehicles. The proposed solution provides protection from an inflow of dust and magnetic powder into the rotor that can deteriorate the motor performance and cause burnout. In addition, unless it is a water-cooled or oil-cooled structure, cooling of an electric motor used in medium and large-sized equipment is not easily accomplished. However, completely enclosed motors are vulnerable to overheating; therefore, research into housing design is required to provide cooling. Additionally, the permissible current density through the stator winding must be considered in the design to prevent the occurrence of thermal demagnetization of permanent magnets. Furthermore, IPMSMs require a separate driver for operation and speed controls for a wide range of operating conditions such as rail traction. Thus, a study has been conducted on IPMSMs and other related driver and control technologies, and their suitability has been validated through performance tests.

A kind of new “dust-free” rice thresher

The project was designed based on air curtain dust control of novel small rice threshing apparatus, mainly involves dust reduction in the working process of agricultural machinery, specifically belongs to the field of agricultural machinery emission reduction. The apparatus is designed feeding modules, threshing modules, dust module, the control module total four modules, means by using a vertical multi-feeding port semi-feeding type of structure, in the while maintaining efficiency reduction rolling straw produced powder dust and realizes dust removal from the source. By adopting the air curtain dust control technology, the dust produced is restrained within the specified range at the first time of diffusion, and further dust control is realized.

Experimental Study on Eco-Friendly Green Cement With Partial Replacement of Cement with Flyash, GGBS and Granite

Concrete is considered as a strong and durable construction material lasting over a century. Reinforced concrete is one among the most popular materials used for construction around the world. reinforced concrete is subjected to deterioration in harsh environment like costal regions therefore, sereveral researchers are striving hard with their efforts towards developing a new material to overcome this problem. This research investigates the utilization of marble dust powder in concrete, where marble A Green cement is a revolutionary topic in the history of cement Industry. This was first invented in Denmark in the year 1998.It presents the feasibility of the usage of By product materials like Flyash, GGBS(Ground granulated blast furnance slag),Graintedust. The use of Flyash in cement contributes the reduction of green house emission with negative impacts on the economy .It has been observed that 0.9tons of CO2 is produced per ton of cement production. It accounts for around 5% of world’s CO2 emission. it avoids the pollution and resue the materials the present study is carried out. Green cement reduces the shrinkage, creep, less heat of hydration and better workability and it requires less energy for its production ,Green cement is used in construction of bridges, buildings, dams and roads.

Technoeconomic Assessment of Organic Halide Based Gold Recovery from Waste Electronic and Electrical Equipment

Waste Electronic and Electrical Equipment (WEEE) is one of the fastest growing waste streams worldwide, with significant economic value due to the precious metals contained within. Currently, only a small share of the total globally produced quantity produced is treated effectively and a large amount of valuable non-renewable resources are being wasted. Moreover, the methods currently applied in industry on a large scale are not always environmentally friendly. Thus, an economically viable and environmentally friendly method that would achieve high recovery of certain elements is sought. The objective of this paper is to assess four different organic halides as leaching agents for gold recovery from WEEE. Two of them have been previously tested (namely N-bromosuccinimide, NBS, and N-chlorosuccinimide, NCS) and have shown promising results, whereas the other two are novel and were selected due to their lower toxicity levels (trichloroisocyanuric acid, TCICA, and tribromoisocyanuric acid, TBICA). Both commercially supplied pure gold powder and WEEE dust from a recycling company were used as the gold source. Results show that from a technical standpoint, the NBS is a superior solution with both substrates, reaching 61% and 99% extraction efficiency from WEEE dust and pure gold, respectively. The other three methods recorded lower recovery efficiency (with the highest value reaching 36% for NCS, 53% for TCICA and 29% for TBICA). However, taking into account the price of gold and the expenses of the extraction process, only three of the lixiviants tested (NBS, NCS and TCICA) could be potentially profitable and viable on a larger scale.

A review on alternative binders, admixtures and water for the production of sustainable concrete

To keep its leading role, the concrete industry must face the environmental issues linked to the manufacturing, by increasing the energy efficiency and adopting alternative fuels or raw materials. The present work analyses physical, mechanical, and environmental performances of concrete products incorporating waste from four main sources (construction and demolition waste, residues from waste treatment, metallurgical industry by-products and other sources), as substitutes of one of the three main components of concrete (binder, admixtures and water). The binder is the easiest component to be replaced in terms of number of alternatives, with the highest impact on concrete properties, while water easily reaches a full replacement level. Ground granulated blast furnace slag (GGBFS) showed the highest potential for the overall performance, with positive effects on compressive strength, durability, and workability of concrete samples, along with electric arc furnace dust (EAFD) and ceramic powder.

Effect of Waste Glass Powder and Stone Dust on the Characteristics of Concrete

Effect of Waste Glass Powder and Stone Dust on the Characteristics of Concrete

Potential utilization of construction wastes in asphalt pavements as fillers using ranking framework

This study explored the potential of four construction wastes namely brick dust (BD), concrete dust (CD), glass powder (GP), and limestone dust (LD) as fillers in asphalt concrete mixes using a decision-based ranking framework. The asphalt concrete mixes containing aforesaid fillers were designed and their optimum asphalt content and effective filler-binder ratios were assessed. The mastics corresponding to the estimated filler-binder ratio were prepared and their viscoelastic properties, as well as resistance against fatigue and rutting resistance, were analyzed. Asphalt concrete mixes containing waste fillers were also assessed against cracking, moisture permeation, and rutting. Additionally, the economic benefits and environmental viability of various wasted were also compared. The aptness of fillers was evaluated using a ranking methodology; in which suitable weightage is given to different test results, based on possible conditions on the field by the decision-makers. Asphalt mix containing fine fillers (LD, CD, and GP) exhibited superior resistance against rutting as well as cracking resistance. Asphalt mixes containing CD and LD displayed better moisture resistance due to the calcium-based minerals in them. Mixes containing LD and BD fillers were found to be more economical and environmentally friendly than conventional stone dust mixes. Based on the suggested ranking methodology, LD and GP emerged as the best and poor performing fillers respectively.

Evaluation of Botanical Powders for the Management of Rice Weevil (Sitophilus oryzae L. Coleoptera: Curculionidae) in Rupandehi, Nepal

An experiment to manage rice weevil (Sitophilus oryzae L. Coleoptera: Curculionidae) in wheat (Triticum aestivum L. Gramineae) was carried out at Institute of Agriculture and Animal Science (IAAS), Paklihawa Campus, Rupandehi, Nepal. The experiment was conducted under completely randomized design (CRD) with seven treatments viz. neem leaf dust (Azadirachta indica A. Juss) 15 g/kg, tobacco leaf dust (Nicotiana tabacum L.) 10 g/kg, ginger rhizome powder (Zingiber officinale Roscoe) 20 g/kg, garlic cloves powder (Allium sativum L.) 20 g/kg, Sichuan pepper seed powder (Zanthoxylum armatum Roxb.) 10 g/kg, sweet flag rhizome dust (Acorus calamus L.) 5 g/kg, and control with three replication. Result revealed that the highest mortality of weevils was observed in the wheat seed treated with A. calamus (98.33%), followed by N. tabacum (85.67%), A. sativum (73.34%), A. indica (70.67%), Z. armatum (70.34%), and Z. officinale (58.34%). Similarly, the lowest percent weight loss (3.32%) and damage of seed (4.0%) were observed in wheat treated with A. calamus. Moreover, the highest germination (89%) was observed in seeds treated with A. calamus rhizome powder when tested at 90 days after treatment application. Based on weevil mortality and the germination test, it is found that sweet flag rhizome powder is the best treatment against rice weevil followed by tobacco leaf dust and garlic clove powder. Therefore, these botanicals could be one of the effective alternatives for the management of weevil especially to the farmers who do not use chemical insecticides in the rural areas of Nepal.

Removal of trivalent chromium from tannery wastewater using solid wastes

The leather tanning industry is one of the important industrial activities in Egypt. However, this industry produces large amounts of wastewater containing trivalent chromium Cr (III) residues that are considered, if not treated, a significant risk to the environment. Although Cr (III) is not as toxic as Cr (VI), there is a high possibility that Cr (III) residues can be oxidized to Cr (VI). Due to this risk, chromium removal from tannery wastewater becomes a vital process. The current study demonstrates the ability of the use of different solid waste materials in the removal of trivalent chromium from tannery wastewater. Four agricultural waste materials and two industrial solid waste materials were tested. The agricultural solid waste materials include rice husk, rice straw, sugarcane bagasse and sawdust; while the industrial waste materials include cement kiln bypass dust and marble powder. The results showed that the cement kiln dust and marble powder can provide the highest removal of chromium from aqueous solution. The results also showed that cement kiln dust can remove more than 99% of the trivalent chromium when the pH of the solution is raised above 8.75.

MODIFICATION OF ASPHALT MIXES USING WHITE CEMENT DUST AND IRON FILINGS AS A FILLER

The possibility of using white cement dust and iron filings as fillers to modify asphalt mix properties was investigated. Numerous aggregate tests were conducted, including sieve analysis, specific gravity, absorption, and abrasion tests. Several bitumen tests were also conducted, including penetration, softening point, ductility, flash point, and specific gravity tests. Marshall properties were used to evaluate the physical performance of the mixtures. The construction of pavements with iron filings in hot asphalt mixtures is not recommended, but white cement dust powder or limestone powder can be beneficial. A 5% content was observed to be the best white cement dust content. There is no clear relationship between air voids and the percentages of white cement dust and iron filings, as the curve fluctuates. The use of white cement dust as a filler always exhibits better results; therefore, using white cement dust widely is recommended over using iron filings.

Utilization of recycled form of concrete, E-wastes, glass, quarry rock dust and waste marble powder as reliable construction materials

Abstract Due to the elevated price of conventional constructional materials in the market; the cost of an entire civil engineering project is influenced. With increasing consumption & depletion of the naturally found aggregates, it is becoming more of an environmental issue rather than being commercial. Now-a-days, many researchers are contributing to find out the material which can lessen the construction cost without compromising upon durability parameters as well as increase the strength. Recently on the environmental issues, restrictions on local extraction, procurement of natural sources for construction usage and upon “disposal of waste material” are in limelight importance. If waste materials can be incorporated as aggregates in concrete, they can not only be utilized in concrete and other construction materials, but will also provide other cost benefits as well as environmental benefits such as reduction in pollution, energy efficient, cost reduction in landfills etc. In this paper, recycled form of concrete, e-wastes, glass, quarry rock dust and waste marble powder have been investigated. This paper attempts to present a summary of the investigations on the above said in an attempt to make concrete lightweight, economical along with the following discussion, safe & eco-friendly and look for the feasibility of such waste products that can be utilized as reliable construction materials.

Effect of particle size and weight percent of different wood dust on the tensile strength of glass fiber Epoxy/Saw dust composite using RSM

Nowadays demands of glass fiber epoxy based composite is increasing very rapidly. In this investigation effect of particle size, weight percentage and types of saw dust powder on tensile strength is investigated. Response surface methodology was used for the analysis of specimens. Further analysis of variance is employed to investigate the effect of contribution of individual process parameters. Furthermore a regression model is developed to predict the tensile strength of the glass fiber epoxy/saw dust composite. Confirmation experiments validated that developed model is valid within the experimental domain. The peak value of tensile strength 18.72 MPa is observed at process parameters i.e. wood dust type of rubber, wt.% of 18% and particle size of 550.83 µm.

АЛЛЕРГЕННАЯ АКТИВНОСТЬ И ОПАСНОСТЬ ПРОМЫШЛЕННОЙ ПЫЛИ СУХИХ ПРОДУКТОВ ПЕРЕРАБОТКИ КОРОВЬЕГО МОЛОКА

The purpose of the work was to establish in a model experiment the allergenic activity and danger of the extracts obtained from the dust of dry products of cow's milk processing (DPMP), containing complexes of soluble whey (WMP) or casein milk proteins (CMP), as a stage of hygienic regulation of the content of dust DPMP in the air of the working area. Experiments on albino guinea pigs sensitized by the intradermal injection of standard doses of WMP and СМР solutions into the ear revealed the development of severe allergic reactions in the animals of the experimental groups with the prevalence of mixed mechanisms of immediate anaphylactic and delayed cell-mediated types. According to the criteria for the classification of industrial allergens, the WMP and СМР complexes have a strong allergenic activity and are differentiated to the 1-st class of allergenic hazard, which determines the classification of the DPMP dust containing them as extremely dangerous industrial allergens. This is confirmed by the established high levels of indicators of allergic-diagnostic reactions in vivo and in vitro when testing sensitized WMP and СМР animals with a solution of skim milk powder dust, indicating the presence of antigenic determinants of whey and casein milk proteins in it and a real ability to form cross-allergic reactions in the body of workers to dust from all dry milk processing products containing these proteins.

Synthesis and characterization of starch based bioplatics using varying plant-based ingredients, plasticizers and natural fillers.

With the ever-increasing demand of plastics in the world and their consequent disastrous effects on environment, a suitable environmental-friendly substitute like bioplastics/biodegradable plastics is the need time. This study centers on green-production of a variety of bioplastic samples from (1) banana peel starch (BPP) and (2) a composite of banana peel starch, cornstarch and rice starch (COM) with varying amounts of potato peel powder and wood dust powder as fillers, respectively. Two different plasticizers – Glycerol and Sorbitol – have been utilized separately and in a 1:1 combination. A total of 12 samples of each of two types of bioplastics were made using multiple amounts and combinations of the fillers and plasticizers, to test the differences in the physical and chemical characteristics (moisture content, absorption of water, solubility in water, solubility in alcohol, biodegradation in soil, tensile strength, Young’s modulus and FT-IR) of the produced samples due to their different compositions. The differences in the properties of the bioplastic samples produced make them suitable for usage in many different applications. All 24 of the samples produced were synthesized using natural and environmentally safe raw material and showed biodegradation, thus proving to be a good alternative to the conventional plastics.

Prescribed medication use among elementary teachers: Prevalence and associated factors.

The aims of the study were to assess the prevalence and analyze the associated factors of medication use among teachers. A cross-sectional study was carried out, involving 530 teachers from Londrina city, Paraná, Brazil. The dependent variable was prescribed medication use and the independent variables were sociodemographic, work-related, lifestyle, health disorders, and chronic diseases, all assessed through questionnaires. Prevalence of medication use was 59.1%. Chronic disease was associated with all medications analyzed. Variables positively associated with medication use according to health disorder type were: Cardiometabolic (Length of employment, overweight, not current tobacco use, and TV viewing); Psychological (Length of employment, common mental disorders, current tobacco use, and disability); Orthopedic (Length of employment, health insurance, overweight, musculoskeletal pain, low job support, and disability); Respiratory (TV viewing and problems related to dust or chalk powder); and Gastrointestinal (common mental disorders and physical activity [negative association]). Support for access, the appropriate use of medicines, and a reduction in medication use should consider work-related, lifestyle, and health disorders, as well as chronic diseases.

WITHDRAWN: Structural performance of fiber reinforced concrete made from industrial waste products

Abstract In India, consumption of concrete for the wide range of establishments on the field of construction is huge over the past few decades. Recent days, Exploitation of natural resources are taken into huge concern and numerous investigations are done to determine the suitable alternative materials for the various ingredients of concrete. Over the various researches it is observed that the different industrial waste products can be used as a substitute material in the concrete production which could deduce the problems associated with disposal those waste products into the environment. In this study, marble powder (MP) and quarry dust (QD) are utilized as a replacement for natural river sand and the replacements were done from 0 to 50% at an interval of 25% in varying proportions of MP and QD. To increase the strength and crack resistance of M20 grade concrete, basalt fiber was added into the concrete matrix at 0.5% by the weight of cement. Structural and seismic performance of concrete mixes were assessed by conducting flexural strength test on RC beams of size 150 × 200 mm and 1800 mm length. Two-point loading condition was employed on the RC beams of effective length 1500 mm. Downward displacements were measured at L/3 distance from the supports and L/2 distance while the application of loading at constant rate. It is observed that fiber concrete mixes made with river sand, MP and QD of 50%, 25% and 25% shows better results and provides better seismic resistance without compromising the strength and quality aspects. It may also conclude that they may be useful to construct RC structures in the seismic zones.

The effect of vegetal mulching on soil surface temperature in semiarid Brazil

Summary Understanding the temporal and spatial dynamic of soil temperature is crucial for agriculture, since it affects soil evaporation and soil biological activity, influencing seed germination, root growth and absorption of water and nutrients by crops, and ultimately the runoff process. Mulching is one of the most applied soil and water conservation method for soil moisture and soil temperature variations control. This study aimed to investigate the influence of three different mulch types (dried elephant grass straw, dried cashew tree leaves and coconut powder or coir dust), applied with three area densities (2, 4 and 8 t ha−1), on the soil surface temperature, under field conditions in the Brazilian semiarid region. Soil temperature monitoring was carried out using thermocouple sensors and an infrared camera in the Brazilian semiarid region. Results show that mulching provided a buffer zone, dampened soil temperature fluctuations over time, mainly for the 8 t ha−1 density. Mulching reduced soil temperature during the hotter period of the day and increased soil temperature during the night period.

A user-secure and highly selective enhancement of latent fingerprints by magnetic composite powder based on carbon dot fluorescence

A novel bifunctional composite powder with moderate magnetic properties and intense fluorescence was prepared via a layer-by-layer assembly route. After the self-assembly procedure run up to 7 times, the as-prepared Fe3O4@SiO2-CD(n) began to overcome the quenching effect from Fe3O4 nanoparticles and shown intense blue emission (λem = 434 nm) under 370 nm UV irradiation with a quantum yield of 45.04%. The morphological characterization revealed that it has a spherical and uniform core-shell structure of approximately 120 nm in diameter. The component analysis and contact angle test manifested the hydrophilic groups on the surface of the final products. As a result, this novel nanocomposite powder has two advantages over traditional fingerprint powder in both morphology/size and organic functional groups, which could provide more suitable physical adsorption and more chemical bonding in the interaction between fingerprint residues and powders. A series of fingerprint enhancement experiments and a novel quantitative evaluation both confirmed its high contrast, high sensitivity, and especially high selectivity over traditional methods for latent fingerprints. More importantly, in addition to its saturation magnetization of 6.4 emu/g, the abundant hydrophilic groups on the surface of our composite powder also played an important role in absorbing moisture in air and print residues to avoid powder dust from the user’s respiratory tract. Therefore, a fast, user-secure, and highly selective method was established and expected to be valuable in forensic science and related fields.