Effect of Dust

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Effect of Dust Aerosols in Forming the Regional Climate of Georgia

Effect of Dust Aerosols in Forming the Regional Climate of Georgia

2. Model description and data. This study is based on the fourth generation regional climate mod- eling system RegCM4 [37], where the mineral dust particles’ emission, transport and deposition are included [14]. The RegCM4 is a sigma regional climate model with a dynamical core based on the hydrostatic version of the PSU/NCAR Mesoscale MM5 Model [38]. The model has been widely used and tested for the study of regional climatic change and especially for simulations of the effect of dust aerosols in forming the regional climate [6,14,37]. The coupled dust module includes dust emission, transport (wet and dry removal), grav- itational settling and optical properties’ calculations. The dust emission scheme completely depends on the simulated surface wind threshold friction velocity value, boundary layer atmosphere processes and land surface characteristics (surface roughness and soil moisture) which are provided by the surface biosphere-atmosphere transfer scheme BATS. We examine the role of mineral dust effect in forming the regional climate of Georgia by RegCM4/dust model as dust represents the main pollutant for the territory of Georgia [25,39]. During the last decades, there has been a significant improvement in understanding of the dust sources, its transportation, properties and in modeling capabilities [39]. In our study the dust particles are divided into four size bins: fine (0.01-1.0 µm), accumulation (1.0-2.5 µm), coarse (2.5-5 µm), giant (5.0-20.0 µm) and we used four steps in dust parameterization [39]. The dust transport, deposition and removal processes have been described in detail in articles [40] [41] and were used in this study.
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Long-Term Effect of Dust Control on Blood Lead Concentrations

Long-Term Effect of Dust Control on Blood Lead Concentrations

Children’s blood lead levels, measured at baseline and at 6-month intervals until 24 months of age (ie, at 6, 12, 18, and 24 months of age) and annually thereafter (ie, 36 and 48 months of age) were the primary measures used to evaluate the effect of dust control. Venous samples for children’s blood lead were obtained by using techniques to ensure minimal extraneous lead contami- nation. Blood lead was determined by using Electrothermal At- omization Atomic Absorption Spectrometry (New York State De- partment of Health, Wadsworth Laboratories, Albany, NY). All reported results are the means of 6 separate analyses (3 aliquots/ day measured on 2 consecutive days) performed on each blood sample.
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Evaluation of Effect of Dust on Polycrystalline Silicon Solar Cell

Evaluation of Effect of Dust on Polycrystalline Silicon Solar Cell

results in power shortage, so solar PV system is proven best in atmospheric conditions of region like India. Efficiency and Fill factor of solar PV system are degraded due to dust and similar pollutants. The accumulation of dust on the surface of a photovoltaic module decreases the radiation reaching the solar cell and produces losses in the generated power. Dust not only reduces the radiation on the solar cell, but also changes the dependence on the angle of incidence of such radiation. This work presents losses caused by the accumulation of dust on the surface of photovoltaic modules and effect of dust layers on the transmissivity of PV module glass.
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A Simulation Study on Channel Estimation for Cooperative Communication System in Sand dust Storm Environment

A Simulation Study on Channel Estimation for Cooperative Communication System in Sand dust Storm Environment

There are many factors that influence the propagation of electromagnetic wave in the sand-dust storm environment, the scattering effect of dust particle is one of the major factors, so this paper focuses on the dust particles scattering function. The scattering of dust particles inevitably brings the multipath transmission of the signal, multipath propagation will bring the multipath fading of the signal. In this paper, we first investigate the use of AF and DF modes in a sand-dust storm environment. Secondly, we present a low-order modulation method should be used in cooperative communication system. Lastly, we evaluate the system performance for both of the moving nodes and power allocation. Experimental results validate the conclusion of theoretical derivation: the multipath fading is one of the main factors that affect the quality of signal transmission. Cooperative communication technology has good anti-fading ability, which can guaran- tee the signal transmission timely and correctly.
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New apparatus for skid testing : assessment for dusty surfaces

New apparatus for skid testing : assessment for dusty surfaces

Skid resistance act as a friction force when a vehicle moves. It is an important property for safe maneuver of vehicles. The effect of dust surface on the road surface is highly significance to motorcycle where its maneuver depends largely on the balance and stability of the friction force. Riding hazard occurs when motorcycle is side by side with a large vehicle. Large vehicle would travel near center of the road thus motorcycle is force to ride along the dusty path. A slight skidding would end up with an injuries accident. Although there is no actual statistical count of such accident or those slight injuries caused by own crash, the risk of hazard is not to be underestimated. The skid resistance property is controlled by both the pavement and tyre of vehicle. The contact surfaces of both become the key to skid property. Thus, it is of highly importance to identify the effect of dust on road surface toward the skidding resistance property.
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EFFECT OF CRUSHER DUST ON SHEAR PARAMETERS OF PANTNAGAR SOIL

EFFECT OF CRUSHER DUST ON SHEAR PARAMETERS OF PANTNAGAR SOIL

For the design of earthen dams and embankments shear parameters are required. These are also used in calculating the bearing capacity of soil foundation. This research is an attempt to investigate the effect of Crusher Dust on cohesion and angle of internal friction of Pantnagar soil. Various percentages of Crusher Dust by dry weight of soil were taken and uniformly mixed with soil. The shear strength parameters were determined according to IS: 2720 (Part 13)-1986. The samples were prepared in the size of 60mm×60mm×25mm and sheared at a rate of 1.25 mm/minute. The result obtained shows that the cohesion of soil decreases on increasing the crusher dust content from 0% to 50% and angle of internal friction increases on increasing the crusher dust content 0% to 50%.. Laboratory experiments favorably suggest that mixing Crusher Dust with soil would be effective in improving shear parameters of Pantnagar soil.
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Effect of Iron Dust on Lime Stabilized CL Soil

Effect of Iron Dust on Lime Stabilized CL Soil

Bell, F.G., (1996) conducted lime stabilization of clay minerals and soils. Clay soil can be stabilized by the addition of small percentages by weight of lime, thereby enhancing many of the engineering properties of the soil and producing an improved construction material. Kaolinite, montmorillonite and quartz were subjected to a series of tests. All materials experienced an increase in their optimum moisture content and a decrease in their maximum dry density, as well as enhanced California bearing ratio, on addition of lime. Some notable increases in strength and Young's Modulus occurred in these materials when they were treated with lime. The optimum gain in strength appears to be with 4-6% lime. Arash Barazesh et al., (2012) studied the effect of adding Iron powder on Atterberg’s limits of clay soils. In this research, iron powder combined with clay soils in order to examine its effects on the Atterberg’s limits of the soils. Five different types of soil with initial plasticity indices of 26, 31, 35, 39, and 49 are used for this experiment. Plasticity indices (i.e. LL, PL, and PI) of the sample soils combined with different percentages of waste iron powder examined and compared with the plasticity of the original soils.
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Effect of lift force on the aerodynamics of dust grains in the protoplanetary disk

Effect of lift force on the aerodynamics of dust grains in the protoplanetary disk

In this paper, we investigated the effects of the lift force on dust grains in a protoplanetary disk from two perspec- tives. We first investigated whether the lift force is kept exerted on the grains or not. We assumed the grains are in the minimum mass solar nebula where the turbulence develops. We estimated the collision timescale and the spin-down timescale and found that the grain keeps spin- ning as a result of collisions with the other grains if the radius of the grain is larger than 100 cm at 1 AU from the central star.

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Effect of Fly Ash and Quarry Dust on Properties of Concrete

Effect of Fly Ash and Quarry Dust on Properties of Concrete

From the Figures 1 and 2 , it is observed that the maximum strength occurs at 20% fly ash in case of 20% quarry dust (M3) and 30% quarry dust (M7) whereas it attains maximum at 10% fly ash in case of 40% quarry dust (M10) irrespective of curing period. The mix comprising 20% fly ash and 30% quarry dust (M7) attains higher strength irrespective of curing period among all the mixes considered. When compared to controlled concrete, for M7 mix the amount of improvement in strength of cubes is about 37%, 30%, 36%, 20% and 10% at 7, 14, 28, 56 and 90 days of curing period and the improvement is about 23% at 28 days of curing period in case of cylinders.
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Effect of Lime Stone Dust on Geopolymerisation and Geopolymeric Structure

Effect of Lime Stone Dust on Geopolymerisation and Geopolymeric Structure

The compressive strength of the geopolymer paste was determined after 28 days from manufacture. There was slow increment in compressive strength with time beyond 28 days for the samples without Lime stone dust the strength trends were likely to change over time as high NaOH geopolymer leaned to cure more slowly [13]. Three specimens for each series were crushed in a digital compression testing machine and the average is reported. As fracture behavior of the samples was often unpredictable as few areas were chip of prior to ultimate facture, successful samples were indicated only when there was a single break of the materials [14]. Compressive strength obtained for the specimens are presented in Figure 5. The key role played by the Ca ions in the geopolymer skeleton. Infact the high CaCO 3 content effects in quicker
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Experimental Studies on the Effect of Silica Fume and Quarry Dust in Concrete

Experimental Studies on the Effect of Silica Fume and Quarry Dust in Concrete

5. Bhikshma et al. (2010): The stone dust as replacement for natural sand enhances the strength of concrete mix. The rough profile of stone dust provides good interlocking and bond between ultra fine particles of cement paste. The concrete is less permeable and durable than conventional concrete with river sand. The compressive strength increased significantly up to about 20% for concrete with crusher dust compared to conventional concrete.

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Effect of Cement Kiln Dust on Some Properties of Soil

Effect of Cement Kiln Dust on Some Properties of Soil

The cement industry also plays an important role in the imbalances of the environment and produces air pollution hazards Stern 1 . It also causes the pollution in soil where cement industries are located. The particles of cement dust can enter into soil in the form of dry, humid or occult deposits and can alter its physical-chemical properties Ahiamadjie et al. 2

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Effect Of Stone Dust On The Mechanical Properties Of Adobe Brick

Effect Of Stone Dust On The Mechanical Properties Of Adobe Brick

Ecologic building materials such as adobe bricks have become of greater economic importance in recent years. Adobe is a form of natural architecture built with environment friendly materials which provide indoor protection from outside temperature conditions. In Bangladesh, adobe brick is getting more popularity as an economical housing material. It is important to consider the strength of adobe brick. This study was conducted to determine the effect of the proportion between the soil and the stabilizers (such as cement and stone dust) on stabilized earth blocks durability. As the experimental program was planned, consisting tests such as density, compressive strength and flexural strength, were conducted to investigate the properties of adobe bricks. The specimens incorporated with different volume fractions of stone dust, i.e. 5%, 10%, 15%, 20% and 25% and the result showed that the use of stone dust increases the compressive strength 10% to 20 % respectively and the moisture content and water absorption of the adobe from dredge soil and cement and stone dust also calculated which was very similar and slightly change with the percentage of stone dust. The results indicate that the use of stone dust of 910 % to 20 %) with 5% cement based adobe enhances the mechanical properties of the adobe and
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Study on Effect of Steel Dust on Strength Characteristics of Concrete

Study on Effect of Steel Dust on Strength Characteristics of Concrete

The concrete is prepared in laboratory. The concrete is poured into the mould in 3 layers by 25 strokes with tamping rod. The cast specimens are removed after 24 hours and these are immersed in a water tank. After curing 7 and 28 days the specimens are removed and these are tested for Workability, Compression, and Split tensile strength is found out for concrete which was replaced with steel dust in the proportion of

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USE OF BRICK DUST AND FLY ASH AS A REPLACEMENT OF FINE AGGREGATE IN SELF COMPACTING CONCRETE

USE OF BRICK DUST AND FLY ASH AS A REPLACEMENT OF FINE AGGREGATE IN SELF COMPACTING CONCRETE

The main objectives set for this research are to compare the mechanical properties of self-compacting and normal concrete specimens. The criteria used will be based on 7days, 28-day and 56 days compressive, splitting tensile and flexure strength and of conventional and self-compacting concrete for five Fly ash & Brick dust ratios as a replacement to fine aggregate. Accordingly, the present study is aimed to develop a concrete with good strength, less porous, so that good durability will be achieved. For this purpose, Brick kiln dust is used as a pozzolanic materials. Precisely;
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Effect of Quarry Dust on Class C Fly Ash Concrete

Effect of Quarry Dust on Class C Fly Ash Concrete

In the literature survey reported that the fly ash in concrete reduces the compressive strength in early stages and improved in the later stages. The early strength is decreased further increasing the percentage of fly ash. But when increasing the percentage of quarry dust with the fly ash is increasing the strength in the later ages. The 25%, 50% of quarry dust with 20% of fly ash is decreasing the strength and increasing at 30%, 40% of fly ash.So that the 50% replacement of sand along with 40% of fly ah can be achieved.

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Sensitivity simulations with direct shortwave radiative forcing by aeolian dust during glacial cycles

Sensitivity simulations with direct shortwave radiative forcing by aeolian dust during glacial cycles

et al. (2003) than by Takemura et al. (2009). Differences in radiative forcing could be caused by different optical param- eters and the use of different shortwave schemes which im- pede a direct comparison. Claquin et al. (2003) used different single-scattering albedos for desert soils with different min- eralogical composition. Takemura et al. (2009) accounted for size-dependent extinction coefficients (Takemura et al., 2002) and used a RI value for soil dust (see Appendix) based on recent studies (Takemura et al., 2005). The dust loads used for LGM and present day are larger by a factor of about 2.6 in Claquin et al. (2003) than in Takemura et al. (2009). The dust load in Claquin et al. (2003) for present day is 35.3 Tg, which is derived from the global dust emission flux of 3000 Tg yr −1 and the average lifetime of 4.3 days given in Mahowald et al. (1999). The smaller dust load of 13.6 Tg in Takemura et al. (2009) results from a short dust lifetime of only 1.9 days although the emission flux of 2594 Tg yr −1 corresponds to 86 % of the emission flux in Claquin et al. (2003). Their glacial dust emissions show compatible en- hancement factors of 2.5 (Mahowald et al., 1999) and of 2.39 (Takemura et al., 2009). The stronger negative dust radiative forcing in Claquin et al. (2003) could further result from the longer dust lifetime whereby dust aerosols are transported farther downwind from source areas toward dark ocean ar- eas. Hence, larger dust load and longer transport might con- tribute to the more negative forcing for LGM and present day in Claquin et al. (2003) than in Takemura et al. (2009).
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Ashes to Ashes, Dust to Dust

Ashes to Ashes, Dust to Dust

Iserson, Kenneth V., M.D. Death to Dust: What Happens to Dead Bodies? 2nd ed. 1994. Tucson: Iserson, 2001. Print. Somewhat of an encyclopedia of the Mortuary world. The author is a Professor of Emergency Medicine and Director of the Arizona Bioethics Program at the University of Arizona College of Medicine. Information reguarding the history and explanation of embalming, and death rate statistics were taken from this source. Milano, Carol. “Going Green: Be Prepared to Answer Questions on Green Burials.” American

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The Cement Kiln Dust (CKD) was obtained from Sokoto Cement Factory, Sokoto, the capital of Sokoto State of Nigeria directly from the factory’s kiln dust collection cylinder. The characterization of the CKD by determining its chemical composition was conducted by method of Energy Dispersive X-Ray Fluorescence at the Nigerian Geological Survey Agency, Barnawa- Kaduna. The loss on ignition content of the CKD used in this study was characterized as high (39.28%) considering the literature review of Bhatty and Todres [9].

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Effect of volatile matter from wood chips on the activity of house dust mites and on the sensory evaluation of humans

Effect of volatile matter from wood chips on the activity of house dust mites and on the sensory evaluation of humans

Abstract The effect of volatile matter from various wood chips on house dust mites and their influence on human comfort were measured. To investigate the effect of vol[r]

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