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This study aims, through experimental works, to develop a new and sustainable binder by reusing two waste materials, namely waste paper slag ash (WPSA) and granite dust (GD) to stabilize fine-grained soil and reduce the environmental impacts resulting from improper disposal in addition to reducing the use of cement and lime in soil stabilization. The soil utilized in this research was obtained from a site near 80th Street in Babylon Provence. The experimental works included sieve and hydrometer analysis, consistency limits, compaction test, and unconfined compression strength test at 3, 7, and 28 days of curing. Various binary blended binders derived from mixing of WPSA and GD at different proportions; 10:0, 7.5:2.5, 5:5, 2.5:7.5, and 0:10 were utilized. These binary blended binders were mixed with the virgin soil at 10% in the samples testing procedure. The results showed that the use of the mixture containing GD alone resulted in a reduction in the LL, PL, and PI, and when increase the percentage of WPSA in the mixture, LL and PL were increased while PI decreased. Moreover, the maximum dry density of the treated soil increased with the use of GD, however, it decreased significantly after the employing WPSA in the binder used. As per the outcomes of the compressive strength test, it was shown that the use of the mixture WPG0 that contains (100% WPSA) gave the highest compressive strength, which is equivalent to 14 times of that for the virgin soil after 28 days of curing. The strength then dropped with increasing the percentage of granite dust in the mixture. However, mixtures contained both of WPSA and GD exhibited acceptable compressive strength throughout the time of curing as the results indicated. [ABSTRACT FROM AUTHOR]

The current study was conducted in Al-Zafaraniya area, southeast of Baghdad, on the Al-Rusafa side, and is one of the largest residential sectors within Baghdad, with a population of about 650,000 and characterized by deferent activities. Four sampling sites were selected, and codes A, B, C, and D were given to represent site-1 industrial activity sites, site-2 service workshops, site-3 commercial activity, and site-4 residential areas, respectively. Street dust particles samples were collected using wooden tools and paper bags, three points were selected from each site, the samples were mixed, and 1 kg was taken to separate and analyze molecules, nature forms, composition, and interaction between their sources. The results of mechanical separation by vibrating soil sieve showed that these remaining consist of several sizes and weight categories resulting from the following form (greater than 2000, 2000, 1000, 500, 250, 150, and less than 53) μm and (108.90, 118.63, 219.88, 191.93, 32.16, 247.58, 3.96) g/kg, respectively. Laboratory tests using polarized microscope technology showed that dust particle components varied from artificial, organic, inorganic, minerals, synthetics substances, and biological residents. When examining the forms of its, they appeared to be different shapes as well as stellar, needles and serrated shapes, sharp angles, and irregular edges, as well as the usual spherical and smooth-edged soil particles. When comparing the values of the 7th category, which constitutes the danger reservoir between the street dust particles because it can turn into suspended and accumulated dust, we find that its values (A 4.8, B 2.86, C 1.2, and D 7.0g/kg) hence find that, the highest value (7.0 g) was recorded in the residential site-D, and this gives an indication that the wastes of other sites move to the residential sites and accumulate in them in large quantities, which exposes the public health and components of the ecosystem to many risks. [ABSTRACT FROM AUTHOR]

Mining defines the process of mineral extraction from various source throughout the earth deposit, but it has a drawback of dust generation. There are so many parameters of dust particle in which the matter of 10 microns are incredibly so much harmful. The heavy dust particles are from size range in 2.5µm to 10µm, in which the upper exposure of PM10 particle may results several health hazards such as respiratory system disability, carcinogen, silicosis, heart failure strokes and premature death may happen because of PM10. The PM10 happens due to so many mining actions like as different method of drilling, loading od waste and minerals, blasting at different mine zone, transportation of material at the time of mineral extraction. [ABSTRACT FROM AUTHOR]

This paper is a review on the Adhesive joints, its applications, preparation, types of failures, joints configuration and many other experiments performed in the past, using adhesives will be discussed. Data is collected from all the previous research papers, books and other resources to update the new approaches on adhesive joints. Adhesive bonding is the permanent joining technique, where adhesive is applied in between the two materials to form a bond. Adhesives are widely used in many areas like aerospace structures, transportation, electronic components, furniture, footwear and many other things which we use in our daily life. Single lap joints (SLJ) and double lap joints(DLJ) are most commonly used. Behavior of adhesives can be affected by external factors such as temperature, curing, joint geometry and other will decrease the strength of the adhesive if proper care is not taken. To overcome the environmental effects such as moisture content, temperature, dust particles on the joint bonding a detail study will be performed, to update new methodologies which are discovered in the recent times. Nano particles are also widely used with adhesives which helps the composite to get more resistance to fight with failure factors. Performance of adhesives with and without nanoparticles, selection of adhesives, selection of Nano particles will be also covered in this paper which helps to perform future experiments easily with a reference. [ABSTRACT FROM AUTHOR]

Free-Space Optics (FSO) is an emerging technology that plays a vital role in the future of wireless connectivity, it differs from radio frequencies (RF) in several ways. FSO offers high bandwidth at a low-cost ratio, is immune to electromagnetic interference, operates in an unregulated spectrum, provides enhanced security, and is easier to install and deploy. The main challenge with FSO networks is atmospheric disturbances such as fog, dust particles, smog, rain, and snow, which can make them inaccessible and unreliable in poor weather conditions. This paper examines how Istanbul's unique climatic conditions affect FSO communications, including attenuation from geometry, molecules, atmospheric scintillation, fog, rain, and snow, where Istanbul's strategic location between the two continents Asia and Europe makes it a key hub for data transfer worldwide. To obtain accurate results, meteorological data such as visibility, rain, snow, wind speed, and altitude were acquired from a 4-year archive (January 2020–December 2023) obtained from the Istanbul Meteorological Agency (ATATURK, TU) via the Visual Crossing Company. Based on the analysis results, it was found that Istanbul offers good weather, and the average visibility stays between 11 and 12 km throughout the year. It has the highest annual average visibility and the lowest attenuation values with 0.741 and 0.339 dB/km, respectively. Moreover, the minimum visibility was measured as 3.6 km and the maximum attenuation was 3.27 and 1.9 dB/km for the optical signal wavelengths of 850 nm and 1550 nm, respectively. It should be noted that rainfall occurs on approximately half of the days of the year in Istanbul. The maximum average rainfall rate is 8.78 mm/hr, with an attenuation of 4 dB/Km. However, in 2022, the highest rainfall rate ever recorded in Istanbul was 73.22 mm/hr, with an attenuation of 16 dB/Km. This study will allow us to comprehend and evaluate optical communications in Istanbul's free space, as well as the challenges that it will confront. In order to achieve precise and satisfactory outcomes, the OptiSystem software was utilized to implement Free Space Optical Communication Link (FSOCL), while the MATLAB software was employed to analyze the impact of weather conditions on the channel's performance. [ABSTRACT FROM AUTHOR]

The study aimed estimation some immunoglobulins, blood pressure and lung function tests in workers at Kufa cement factory. The study consisted measure some immunoglobulins, blood pressure and lung function tests in workers at Kufa cement factory in 45 non-smoker male workers employed in kufa cement factory mean duration of employment 15.953±0.873 years and 45 persons unexposed as control. The workers were divided into three groups according to the type of job: cement mill, kiln and packing workers. The paper elucidated that there was a significant elevation (P ≥ 0.05) total serum of IgE in cement mill workers compared with the control group and kiln, packing workers. The study also illustrated that significant decline (P ≥ 0.05) in FVC, FEV1, FEF, FEF 25-50% and PEFR of cement workers in comparison with the control subjects. Also, in current study revealed that a significant reduction (P ≥ 0.05) in FVC of cement mill workers in compared with kiln and packing workers. The results indicated that there was no significant increment in blood pressure (systolic and diastolic) of cement workers compared with control. Conclusion the study recorded that workplace exposure of cement particulate in different departments in kufa cement plant caused negative impacts on immunoglobulins, blood pressure and lung function tests. [ABSTRACT FROM AUTHOR]

Oman has made serious efforts to convert industrial waste into usable building materials. Ordinary concrete has demonstrated a lack of strong mechanical characteristics during compacting, such as honeycombing and segregation. Earlier studies have produced inventive concrete from recycled waste elements with success. Research have also shown that self-compacted concrete is the best way to achieve durable concrete and overcome the aforementioned problems. One such item found in Oman's industrial waste is quarry dust. In this study, experimental research is done to see if waste powder made from quarrying could be used to make self-compacting concrete. The primary goals of this paper are to create SCC mixes with quarry dust that satisfy the standards for workability and compare the compressive strength of the created SCC to the control mix. Self-compacted concrete was designed in three different mixes, Mix-A, Mix-B, and Mix-C, and the outcomes were compared to the Control Mix. Since the control mix contains no quarry dust, it is proposed that it replace 10%, 20%, and 30% of the fine aggregates in the mix. According to EFNARC requirements, the suggested SCC mix designs were tested for viability, including flow ability through slump flow and slump flow at T500 and segregation resistance through V-funnel. Using 150x150x150 mm cubes, all mixtures underwent compressive strength testing in accordance with the BS standard testing procedure. In contrast to the control mix, which completely failed the slump flow test, the results demonstrate that all SCC mix designs have met the stipulated workability criteria of flow ability of 671mm, 679mm, and 702mm for Mix-A, Mix-B, and Mix-C, respectively. Through the V-funnel test, Mix-C has demonstrated the best segregation resistance. With an average compressive strength of 48.8 MPa, Mix-B has proven to be the most effective mix among the three recommended designs. It also has the highest compressive strength of any mix, including the control mix. While the Control Mix, Mix-A, and Mix-C have attained respective pressures of 48.1, 46.1, and 38.6 MPa. The study finds that employing quarry dust in place of fine aggregates can successfully produce SCC. [ABSTRACT FROM AUTHOR]

The idea of the research revolves around the use of by-products of industries (cement kiln dust, fly ash) and their consumption in production of a binder using in manufacture of sustainable concrete with good specifications that exceed the specifications of Portland cement concrete. On the other hand, reducing the manpower, using equipment and tools in casting or compacting of concrete is another factor of sustainability. In this paper, the possibility of using cement kiln dust (CKD) as a percentage of fly ash in the production of alkali activated self-compacting concrete (AASCC) and its effect on the fresh properties, compressive and splitting tensile strength of the resulting concrete was studied., It was observed that the replacement ratios of cement kiln dust CKD instead of fly ash did not affect the workability properties for resulting concrete, where the proportion of (10%) of CKD replacement caused increase in compressive and tensile strengths about 5%, while, (20, 30)% caused decrease in the compressive and splitting tensile strengths about (30, 44)% respectively. [ABSTRACT FROM AUTHOR]

This paper is a study of aspiration efficiency of local exhaust devices approached by an incident flow of dust-laden air. Known past studies dedicated to determining the aspiration efficiency of a circular pipe facing a flow of dust-air mixture include. In contrast, our study is concerned with a more general problem: given a stream of dustladen air approaching a local exhaust device in the form of a circular exhaust hood, we determine aspiration efficiency as a function of exhaust hood length and tilt angle, incident airflow velocity, and terminal velocity of dust particles. Using the method of discrete vortices, a mathematical model of the motion of dust particles in the flow in front of a circular exhaust hood with an axis of symmetry perpendicular to the acceleration vector of gravity is developed, taking into account the formation of two vortex zones at the entrance to the hood, the initial velocity and direction of emission of dust particles. The dependences of the capture range of dust particles formed at different heights above the impenetrable plane on the following parameters are determined: air flow velocity at the exhaust orifice; initial velocities o dust particles and it's terminal velocity; exhaust hood flange lengths. [ABSTRACT FROM AUTHOR]

In this paper, we simulated and investigated microwave heating of biochar containing electric arc furnace dust spherical pellet. The influence of the distribution of components within pellet on the effectiveness of microwave heating was investigated as well as the influence of biochar conductivity. We considered the interaction of pellet with both plane wave in free space and with H10 mode wave in a single-mode waveguide. In addition, effective permittivity and permeability of EAF dust in one of the possible compositions, and of biochar – EAF dust powders mixture depending on the volume fraction of EAF dust were calculated according to effective medium approach. [ABSTRACT FROM AUTHOR]

The Solar Photovoltaic panel cleaning technology can considerably increase the efficiency of generated electricity and also increase the durability of solar panels. The various cleaning methods, such as electrostatic cleaning system, super hyperbolic coating methods, mechanical method, microcontroller based automatic cleaning method, self-cleaning nanodomes and various characteristics of dust particles are discussed in this study. This study demonstrates the various cleaning methods of solar photovoltaic panels. Much research has been done on these methods and many papers have been published, particularly on Martian and lunar mission. The methods were either mechanical or electronica in concepts or both. By analyzing various systems in this study , some of them are shown to be in practice and many are under research. From the analysis and comparison in this study , the best method was the electrostatic cleaning method. [ABSTRACT FROM AUTHOR]

Providing housing units with livability and suitable facilities that can be an appropriate shelter for citizens is one of the main concerns of planners and officials. The problems of lack of access to standard and viable housing units in Iraq that faced major social and economic crises, war and terrorism, are more tangible. This paper tries to examine this problem by comparative, descriptive, field, questionnaire, and laboratory methods. For this purpose, 154 residential units, which are located in 17 residential sectors of south Malta neighborhood in Duhok city were evaluated, and some criteria considered in the present study includes 1-the quality of the buildings, 2-garbage and specks of dirt and stagnant waters, 3-lighting of the passages, 4-smoke and dust, 5-crowd and traffic and voice, 6-having yard or balcony or good landscape or green area, 7-animals and insects, bad odors, 8-access to transport networks. The main aim of this paper is to reveal the disproportion and uniformity of residential sectors and inappropriate residential sectors of Malta neighborhoods using TOPSIS. The Order Performance technique by Similarity to Ideal Solution (TOPSIS) model was ArcGIS were used for analysis and assessment. Shannon entropy was used for weighting criteria which showed that the Smoke and dust, animals and insects, and bad odors had the highest importance in analysis with a weight of 0.178, and 0.168 respectively. The residential unit with number 30 was the best and the most viable building with the highest Ci score (0.361). Residential unit 64 with a Ci of 0.150 was the least appropriate. In general, the west and northwest buildings of the Malta Neighborhood were more suitable for living in. [ABSTRACT FROM AUTHOR]

Solar photovoltaic (PV) modules are essential for producing electricity with little maintenance and development expenditures. The power generation and operational performance are degraded when dust gathers on the PV module's surface. In the current study, the heating season was used to evaluate the amount of dust that had accumulated on the PV front cover glass. The research was done in Tirupati, India, to examine how airborne dust particles changed over time on PV modules. Over the course of five weeks throughout the heating season, dust that had accumulated on identical PV modules over varying exposure times was collected. The details of the photovoltaic modules and a summary of the meteorological data are discussed in this paper. The result shows that the average particle deposition density and dust accumulation rate for the heating season varies from 26.92 to 42.53 mg m−2 and 3.48 to 6.07 mg m−2, respectively. The elemental analysis reveals that the majority of the dust sample's composition is made up of C, O, and Si components, with Br and Tm components found at trace levels. [ABSTRACT FROM AUTHOR]

Accumulation of the metallurgical waste stimulates development of the recycling technologies. The paper investigates the chemical and phase composition of the particular electric arc furnace (EAF) dust which is formed in the gas cleaning system during steel smelting from scrap. It was found that the main components of the EAF dust under study are ZnFe2O4, ZnO, CaCO3, SiO2 and KCl. The XRD phase analysis showed that the prevailing phase is zinc ferrite ZnFe2O4 (62 %). The thermodynamic analysis was carried out using TERRA software. According to modeling, the iron reduction proceeds sequentially ZnFe2O4 – Fe3O4 −FeO–Fe in the temperature range from 500 to 700 °C. Above 510 °C ZnFe2O4 decomposes with formation of ZnO and Fe3O4. Zinc oxide is intensively reduced in the temperature range from 800 to 900 °C passing into the gas phase. [ABSTRACT FROM AUTHOR]

The article discusses the physical processes of fuel combustion that affect the implementation of the concept of smart dust in the monitoring of thermal power plants. The importance of studying physical phenomena that affect the behavior of smart dust is shown, while ensuring the information reliability of production and environmental monitoring of thermal power plants. The article notes that the physical process of burning prepared fuel at thermal power plants is the main process that has the greatest impact on the environment. In this regard, for this physical process, it is necessary to monitor production and environmental indicators using smart dust. The paper presents the concept of using smart dust to analyze the physical process of fuel combustion, analyzes the TPP facilities that provide fuel combustion, gives their meaningful description and temperature characteristics. A new model of the physical process of fuel combustion of a thermal power plant is proposed, on the basis of which, following the concept of smart dust, a network of many miniature devices (motes) is able to evaluate the generalized quality criterion of this physical process for n-1 inputs and evaluate the allowable range of values of the n-th parameter. [ABSTRACT FROM AUTHOR]

Soft soils usually have shear strength values less than 200 kpa such as clay, silty clay, clayey sand, and soft organic clay. The presence of soft soils in engineering sites requires immediate remediation, which is either altering the site, or removing and replacing the existing soil. These solutions are not always applicable. Hence, other methods are needed which soil stabilization one of them. Soil stabilization is the modification of the physical and geotechnical properties of the weak, and soft soil either mechanically by compaction or chemically using chemical stabilizers. This paper presents a comprehensive review on the stabilization of soft soils by utilizing sustainable stabilizers which are waste and by-product materials such as ground granulated blast slag (GGBS), activated GGBS and cement kiln dust (CKD). These stabilizers are utilized as replacement to the traditional binders (cement and lime). The results indicate that GGBS alone gives only a slight enhancement because of the glassy phase of this material. Nevertheless, activation of GGBS by other materials improves the physical and geotechnical characteristics of soft soils substantially while the use of CKD gave remarkable enhancement to the soft soil characteristics. The physical properties are evaluated by Atterberg limits and compaction parameters, and the geotechnical characteristics are evaluated by the unconfined compressive strength (UCS) test. [ABSTRACT FROM AUTHOR]

At the present time, most researchers have tended to achieve the principle of sustainability in terms of cost reduction in addition to reducing and limiting environmental problems and preserving natural resources through the use of some modified materials and materials that achieve all of the above. Therefore, this research paper aims to study the effect of addition of both ordinary Portland cement and waste (natural marble powder) on the performance of cold mix asphalt (CMA) instead of limestone powder (LD) as a filler. Those CMA mixtures were improved through two stages: the first stage of development included the use of OPC as filler instead of the traditional mineral filler, and in three doses i.e., 2, 4, and 6 % of the total weight of the aggregate. While the second stage of development included the use of Natural Marble Dust (NMD) with 2% OPC with three percentages i.e., 2, 4, 6 % of the total aggregate weight to indicate, the optimum proportions to be compared with the OPC which was used alone and reference filler. All samples were subjected to indirect tensile strength test at a temperature of 25ͼC for four treatment periods i.e., 1, 3, 7, and 30 days. The samples were also tested to indicate ITS at a treatment period of 7 days with different temperatures i.e., 25, 40, and60 ͼC as well. A Marshall test was also performed to indicate the stability for the produced mixtures. The results showed that the use of 6% of OPC contributed to improving the mechanical properties of the mixture and increasing its strength compared to the percentages of 2 and 4% of using OPC as well as when using LD in all tests. In addition, the best results for the ITS test were achieved at the lowest temperature of 25ͼC. The use of NMD waste improved the strength of the mixture in all tests significantly and distinctly compared to the use (2, 4) % of OPC and as well as when used LD. Where the current study found the possibility of adopting using of (2% OPC plus 4% NMD) as optimal filler ratios used to improve the properties of CMA in order to achieve best mixture by means of mechanical properties and sustainability as well as economic. [ABSTRACT FROM AUTHOR]

It is necessary to understand the factors that influence PV power output to predict it in the short and long term. By tabulation and graphical explanation, this paper explores the impact of temperature and dust deposition on PV panel performance by evaluating the performance of a PV panel 120Wp. This experiment was conducted at Al-Nasiriyah city (31°03' N, 46°16' E), environmental variables include those variables. Solar radiance, the temperature of the module, accumulation of dust. In January, the solar panel tested the effect of temperature, and dust on the output power and its performance. At 180˚ south, and 45˚ elevation, the solar panel is omitted. The results show that the solar panel operates at maximum efficiency reached 14.97 % during the month. The reduction in power due to the dust accumulated after 15 days of exposure to environmental conditions was 5%..The photovoltaic (PV) panel performance is affected by high cell temperatures. The settlement of dust on panel surfaces may or not be uniform depending on environmental factors such as ambient temperature, wind, and rainfall. It is very important to investigate the influence of dust settlement on the operating characteristics of PV panels, to better understand the losses in performance attributed to soiling. The current-voltage (I-V) Characteristics of the PV panel reveal extensive information to support the degradation analysis of the panel. This paper attempts to understand performance losses in (I-V) characteristics under varying dust deposition are discussed. [ABSTRACT FROM AUTHOR]

Steel manufacturing process may produce waste such as slag, sludge, dust and mill scale. Since it is an unavoidable waste, the abundance of their production is becoming an environmental concern regarding the high rise of solid waste from the industry. There has been some well-known utilization of slag usage in the industry in handling the waste such as in road construction, cementing material as well as sorbent material. These past years had witnessed the ever-growing interest in the slag incorporation into geopolymer product due to their flexibility of the raw material range that makes incorporation of metallurgical slag waste possible. Thus, this paper seeks to review about the utilization of metallurgical slag waste into geopolymer product. The review focusing on the methodology, chemistry and the resulting properties of the geopolymers. Therefore, the paper will highlight on the characterizations of both raw materials and final product in terms of their microstructural, crystalline phase present and functional groups. Moreover, factors affecting the final product properties such as the alkali concentration, type of alkali, curing temperature, weight ratio and other factors that are mostly discussed by previous researchers are also critically reviewed. [ABSTRACT FROM AUTHOR]

Dust storm considers a new influence on free space optical communication (FSOC) link. It is referred to the suspended particle in the atmosphere at the desert environment. A few information about dust storm imposes on us to explore the dust effect on the performance of (FSOC). This paper investigated the realization of FSO link under dust situations and take into account the effect of dust concentration. Some of the metrics used for the assessment of system including received optical power, channel capacity, signal to noise ratio (SNR), bit error rate (BER). It has been found that dust is a severe deterioration that give rise to the link decay under high concentration of dust. Moreover, we noted that the system suffers from working for the long optical link. The increase in the concentration of dust makes the visibility of weather is low, this reason leads to an increase in errors of transmitter data. Furthermore, the system can be work with efficient channel capacity. Therefore, dust can be deem as the decadence optical link in FSO. [ABSTRACT FROM AUTHOR]

In this paper, we have studied creation field cosmology for perfect fluid distribution in the LRS Bianchi type II universe. To obtain universe's deterministic model, the supplementary condition between metric potential A = Bn is used which is obtained by presuming scalar expansion(θ) is proportional to shear scalar(σ) i.e. θaσ where A and B are functions of 't' alone and n is constant. In addition, other physical, and geometrical dimensions of the cosmological model are also explored in this article. [ABSTRACT FROM AUTHOR]

The paper deals with the dust cleaning system at the construction industry, in particular, at the production of granulated foam glass ceramics. The analysis of the construction companies' activity and their harmful emissions has been carried out. The applied methods of protecting working areas from dust, their effectiveness and the need for their use in various industries have been studied. It is proposed to make changes to the dust cleaning system used in the production of granulated glass ceramic foam. To increase the degree of cleaning, it is proposed to install a Venturi scrubber instead of a cyclonic one. [ABSTRACT FROM AUTHOR]

Solar photovoltaics (PV) are a major, clean alternative to fossil fuels and a crucial component of the supply of electrical energy. Temperature, wind speed, and correct installation factors like tilt angle all influence the performance of the PV model. Sand, dirt, and rock mixtures, building waste, and automobile transportation pollution are all sources of the dust that accumulates on solar photovoltaic panels. The solar panels' glass collects dust, which reduces their ability to produce Electricity. In this paper, the dust deposited on panel is mostly cleaned by Manuel methods. Mathematical model of dust Deposition on Solar panel [ABSTRACT FROM AUTHOR]

The paper is devoted to silencers formed by dividing the duct with the multimode composition of sound waves into ducts with a single-mode composition along one of cross-section coordinate. The geometry of the silencer ducts fulfilled from stepped partitions allows meeting the acoustic, aerodynamic and dimensional requirements for silencers of devices that move air flows. For the silencer of the most technological layout the parameters of slotted ducts' expansion chambers were established as well as the possibility to remove dust and moisture from the silencer during operation. For the silencer with reduced aerodynamic resistance the distances between cuts of slotted ducts pushed inside the expansion chambers were revealed. Creating the conditions for single-mode sound propagation along the second cross-section coordinate provides double noise reduction by the silencer. Additional resonator system extends the frequency range of the silencer. [ABSTRACT FROM AUTHOR]

Rolling water drops takes off dust particles from lotus leaf showing self-cleaning performance. Self-cleaning effect has great importance in industry as well as in daily life. The present paper describes the preparation of self-cleaning superhydrophobic coating through simple and low cost dip coating technique. The prepared superhydrophobic surface enact as lotus leaf. Firstly TiO2 nanoparticles were dispersed in ethanol and different concentration of octadecyltrichlorosilane (ODS) was added in TiO2 dispersion. The effect of number of deposition layer on the wettability of the coating was studied. The coating prepared from five deposition layers showed contact angle higher than 150° and sliding angle less than 10°. The superhydrophobicity increases with increasing concentration of ODS. The hierarchical rough morphology which is preferable for superhydrophobicity was obtained. The prepared coatings were stable against water jet impact and showed repellent towards colored and muddy water. Such superhydrophobic coating can find enormous scope in self-cleaning application. [ABSTRACT FROM AUTHOR]

Many types of the waste are generated in industrial manufacture which are incorporated into concrete materials serving as secondary raw materials. One of these wastes is bypass dust from production of cement, which can be used as a cement supplement in cement composites. The cement composites with partial replacement of cement by the bypass dust were subjected to accelerated sulphate corrosion simulation in a special corrosion chamber during two-month period. The impact of diluted sulphate solution of pH 4 resulted in weight changes, increase in water absorption and changes in chemical composition of the composites. [ABSTRACT FROM AUTHOR]

Particulate Matter (PM) consist of tiny solid or liquid particles that floating freely in the air. PM10 refers to the particles which have size up to 10 microns (μm). The smaller the particle size (such as PM1), the more severe it will affect our human health if we inhaled too much into our lungs. In this paper, we used the DustTrack{trade mark, serif} Aerosol Monitor with Model 8520 to obtain the PM distribution (PM10, PM2.5 and PM1) in Penang Island. The in-situ measurement was taken on 10 August 2012 at Georgetown, Batu Ferringhi and Permatang Damar Laut open area. The data obtained was analyzed and interpreted. The results show that the dust level at Permatang Damar Laut was low as compare to the other two areas which are located in town area. The highest PM10, PM2.5 and PM1 dust level with an averaging time of 6 hours was observed at Batu Ferringhi with a reading of 200, 194 and 185μg/m3. This study can provide a guideline to detect and monitor the dust level at Penang Island. Further study can be done to monitor the temporal changes of air quality over Penang Island, Malaysia. [ABSTRACT FROM AUTHOR]

Wood has been widely used for structural and non-structural construction materials. In non-structural construction materials, wood is the main source for manufacturing of furniture, partition walls, composite boards, and etc. Intensive use of wood (e.g., for composite board) led to decreasing in wood stocks worldwide. One way to minimize the use of wood in the manufacture of composite boards is by using other renewable resources (e.g., coffee husk waste). The objective of this paper is to investigate effects of Arabica Gayo coffee husk waste and sawdust wood particles on mechanical and biodegradable properties of composite boards. The coffee husk waste were collected from milling process and then grounded to pass no. 20 mesh. Composite boards usually composed of filler and a matrix (adhesive). Three type of filler compositions used include sawdust alone, coffee husk waste alone, and a combination of both. The adhesive and filler ratio is taken as 30:70, 40:60, and 50:50 of the percent weight of composite boards. The animal adhesive type was used in this study. Samples were prepared using hot press with pressure of 30 Bar. Properties of composite boards evaluated include density, water absorption, and thickness swelling after 24 hours of immersion, static bending, and biodegradable tests. The Arabica Gayo coffee husk waste composite boards produced in this study are comparable in mechanical and biodegradable properties but higher in thickness swelling and water absorption. However, a combination of both saw dust and Arabica Gayo coffee husk waste could reduce thickness swelling development and water absorption of composite boards. Further, results of this study also showed that coffee husk waste has a great potential to be used for the composite board as a wood replacement. [ABSTRACT FROM AUTHOR]

This paper describes the development and validation of computational fluid dynamics modelling of dust barriers for parabolic trough plants. Two differently shaped porous barriers were simulated with a parabolic trough field of up to 25 rows. Sand and dust were introduced into the simulation and the amount that collects on each mirror row was calculated. This was done for different mirror tracking angles and also for the case of no barrier present. The effectiveness of the barriers was evaluated by comparing the reduction in the amount of soiling present on the mirror surfaces. An additional simulation of the Cranfield University wind tunnel was done, with the results compared with experimental data for validation. It has been found that the dust barriers can lead to up to 45% reduction in the soiling in the outer row, with some effect seen as far as 25 rows into the plant. [ABSTRACT FROM AUTHOR]

Workability is a function of the rheological properties of concrete which consist of stability, consistency and compatibility, it is also attributed to the physical property of a newly mixed concrete that determines the homogeneity at which a mix will be placed in form and finished without segregation of the individual materials. This paper presents an experimental work of ongoing research on the effect of two different industrial waste filler (treated alum sludge filler and limestone dust filler) on the workability of normal concrete. The alum sludge waste used in this study was waste from drinking water treatment plant. Both fillers were crushed and sieved to achieve a particle size of 45μm that was used to replace fine aggregate in different percentages 5, 10 and 15. This study was carried out in order to find the definite effect or behaviour of the two filler material on the workability of fresh concrete when used as a replacement of natural fine aggregate. Reduction in workability was observed from 10 to 15% replacement when alum sludge filler was employed in the mix, whereas limestone dust filler had better workability performance than the alum sludge. It was concluded that the addition of 400⁰C treated alum sludge with 5% replacement of fine aggregate yield similar workability behaviour with control mix and addition of 400⁰C treated alum sludge filler with 5 to 10% replacement content of fine aggregate in terms of the workability of fresh concrete is ideal and feasible to employ in concrete. Furthermore, the replacement of fine aggregate with limestone dust filler improved the workability of fresh concrete in all parameters of testing. Thus all percentage replacement content of limestone dust filler showed superior improvement in the concrete workability and said to be a good filling material for concrete when compared with the alum sludge filler. [ABSTRACT FROM AUTHOR]

The paper examines the possibilities of using concrete dust as a partial replacement of cement binder. This dust was obtained as a by-product during the crushing of recycled concrete and therefore it is a raw material whose composition is directly dependent on the type and quality of the recycled material. The main motivation of this research was the effort to use this by-product and while contributing to reducing the environmental impact of cement production. In this research, cement was replaced with concrete dust from 0 to 50% to the cement content and after 28 days tested its compressive strength. Experiments have shown a negative effect when using concrete dust as a cement replacement. Primarily it was a high decrease in compressive strength, which was caused not only by cement replacement, but also by presence of organic substances in dust. This then resulted in foaming of the fresh mixture and subsequently a higher loss of strength. Thus, only a limited amount of concrete dust can be added to the concrete, for example to optimization of particle size distribution. [ABSTRACT FROM AUTHOR]