Showing papers in "International Journal of Physical Sciences in 2010"

Remediation of heavy metals in drinking water and wastewater treatment systems: processes and applications.

Abstract: In small quantities, certain heavy metals are nutritionally essential for a healthy life. The heavy metals linked most often to human poisoning are lead, mercury, arsenic and cadmium. Other heavy metals, including copper, zinc and chromium are actually required by the body in small amounts, but can also be toxic in larger doses. They have the ability of dissolving in wastewaters and when discharged into surface waters, they can be concentrated and travel up the food chain. They can also seep into groundwater, hence contaminating drinking water, thereby harming the consumers of that water. The enactment of several water legislations and guidelines worldwide coupled with the need for environmental sustainability has necessitated the need for several stringent regulations for drinking water supply and wastewater discharge. To achieve unpolluted drinking water distribution and wastewater discharge, several technologies and processes for heavy metal remediation are currently in use. This review was therefore aimed at elucidating the major available technologies for heavy metal remediation in water, with emphasis on their processes and applications. Currently, no one of the existing technologies for heavy metal remediation (chemical remediation, phytoremediation or microbial remediation) is without some form of merits and demerits. There is therefore a proposed need for the utilization of safe and economical multiple/integrated approach for heavy metal remediation. The application of this may offer enormous public health, environmental and cost benefits. Key words: Heavy metals, remediation, water.

Utilization of solid wastes in construction materials

Abstract: The main objective of this study is to investigate the potential use of various solid wastes for producing construction materials. The paper is based on the comprehensive review of available literature on the construction materials including different kinds of solid wastes. The traditional methods for producing construction materials are using the valuable natural resources. Besides, the industrial and urban management systems are generating solid wastes, and most often dumping them in open fields. These activities pose serious detrimental effects on the environment. To safeguard the environment, many efforts are being made for the recycling of different types of solid wastes with a view to utilizing them in the production of various construction materials. This paper discusses the environmental implications caused by the generation of various solid wastes, and highlights their recycling potentials and possible use for producing construction materials. In addition, this paper shows the applications of solid waste based construction materials in real construction, and identifies the research needs. Key words: Construction, construction materials, environment, recycling, solid wastes.

Dynamic weighted discrimination power analysis: A novel approach for face and palmprint recognition in DCT domain

Abstract: Although Discrete Cosine Transform (DCT) is widely employed to extract proper features for biometric recognition, the problem on how to select proper DCT coefficients to obtain the best discrimination effect has not been solved satisfactorily. Some approaches discard the low-frequency DCT coefficients unreasonably and rely on proper premasking window to improve performance. But there is not a uniform criterion to optimize the shape and size of the premasking window, so it is an inconvenient processing for coefficient selection.Three processes, used to enhance discriminant ability in DCT domain, and the relationship between them are summarized and discussed systematically. Furthermore, this paperexplains the phenomenon why the recognition rate is low without discarding the low-frequency DCT coefficients reasonably and then proposes dynamic weighted discrimination power analysis (DWDPA) to enhance the discrimination power (DP) of the selected DCT coefficients. DWDPA does not need premasking window and preserves more DCT coefficients with higher DP. Normalization prevents the DCT coefficients with large absolute values from destroying the DP of the other DCT coefficients that have less absolute values but high DP values. The DCT coefficients with larger DP values are given larger weights adaptively to optimize and enhance the recognition performance. The experiments on ORL, Yale and PolyU databases captured by biometric sensors prove the advantages of DWDPA obviously. Key words: Dynamic weighted discrimination power analysis (DWDPA), discrete cosine transforms (DCT), biometric sensors, face recognition, palmprint recognition.

The effect of the using waste marble dust as fine sand on the mechanical properties of the concrete

Abstract: In this experimental study, the effects of using waste marble dust (WMD) as a fine material on the mechanical properties of the concrete have been investigated. For this purpose four different series of concrete-mixtures were prepared by replacing the fine sand (passing 0.25 mm sieve) with WMD at proportions of 0, 25, 50 and 100% by weight. In order to determine the effect of the WMD on the compressive strength with respect to the curing age, compressive strengths of the samples were recorded at the curing ages of 3, 7, 28 and 90 days. In addition, the porosity values, ultrasonic pulse velocity (UPV), dynamic modulus of elasticity (Edin) and the unit weights of the series were determined and all data were compared with each other. Finally, all of the data were compared with each other. It was observed that the addition of WMD such that would replace the fine material passing through a 0.25 mm sieve at particular proportions has displayed an enhancing effect on compressive strength. Marble dust is a by-product of marble production facilities and also creates large scale environmental pollution. Therefore, it could be possible to prevent the environmental pollution especially in the regions with excessive marble production and to consume fewer natural resources as well through its utilization in normal strength concretes as a substitute for the very fine aggregate. Key words: Waste marble dust, very fine sand, concrete, dynamic modulus of elasticity, compressive strength, sorptivity.

Effect of types of curing on strength of geopolymer concrete

Abstract: In order to address environmental effects associated with Portland cement, there is need to develop alternative binders to make concrete. An effort in this regard is the development of geopolymer concrete, synthesized from the materials of geological origin or by product materials such as fly ash, which are rich in silicon and aluminum. This paper presents results of an experimental study on the density and compressive strength of geopolymer concrete. The experiments were conducted on fly ash based geopolymer concrete by varying the types of curing namely ambient curing and hot curing. The ratio of alkaline liquid to fly ash was fixed as 0.4. For all the samples the rest period was kept as 5 days. For hot curing, the temperature was maintained at 60oC for 24 h in hot air oven. The compressive strength test was conducted for each sample and the results showed that there is an increase in compressive strength with the increase in age for ambient cured specimens. For hot cured samples the increase in compressive strength with age was very less as compared to that of specimens subjected to ambient curing. The density of geopolymer concrete was around 2400 kg/m3 which is equivalent to that of conventional concrete. Key words: Fly ash, geopolymer concrete, alkaline liquid, density, compressive strength.

Potential of vermicompost produced from plant waste on the growth and nutrient status in vegetable production

Abstract: Vermicompost contains plant nutrients including N, P, K, Ca, Mg, S, Fe, Mn, Zn, Cu and B, the uptake of which has a positive effect on plant nutrition, photosynthesis, the chlorophyll content of the leaves and improves the nutrient content of the different plant components (roots, shoots and the fruits). The high percentage of humic acids in vermicompost contributes to plant health, as it promotes the synthesis of phenolic compounds such as anthocyanins and flavonoids which may improve the plant quality and act as a deterrent to pests and diseases. Key words: Phenolic acid, humic acid, earthworms, Eisenia fetida, organic, compost, fertilizer, leachate, photosynthesis, chlorophyll.

Mix design and mechanical properties of oil palm shell lightweight aggregate concrete: a review

Abstract: To build environmentally sustainable structures, especially in developing countries, the possibility of using some agricultural wastes and industrial by-products from different industries as construction materials will be highly desirable and has several practical and economic advantages. Oil palm shell (OPS) is a form of agricultural solid waste in the tropical regimes. Research over the last two decades shows that OPS can be used as a lightweight aggregate for producing structural lightweight aggregate concrete. The density of OPS concrete is around 20 - 25 lower than normal weight concrete. Generally, mechanical properties of OPS concrete are slightly lower than the other types of lightweight aggregate concrete. It seems that from the summary and analysis of the existing information concerning OPS concrete and comparing it with other lightweight aggregate concrete it appears that significant achievements can be attained.

Similarity solution of hydromagnetic heat and mass transfer over a vertical plate with a convective surface boundary condition

Abstract: This paper examined the hydromagnetic boundary layer flow with heat and mass transfer over a vertical plate in the presence of magnetic field and a convective heat exchange at the surface with the surrounding has been studied. The similarity solution is used to transform the system of partial differential equations, describing the problem under consideration, into a boundary value problem of coupled ordinary differential equations and an efficient numerical technique is implemented to solve the reduced system. A comparison study with the previous results shows a very good agreement. The results are presented graphically and the conclusion is drawn that the flow field and other quantities of physical interest are significantly influenced by these parameters. Key words: Vertical plate, convective boundary condition, heat and mass transfer, magnetic field, similarity solution.

Simultaneous robot-world and hand-eye calibration using dual-quaternions and Kronecker product

Abstract: Two solutions of the homogeneous matrix equation AX=ZB, that allows a simultaneous computation of the transformations from robot world to robot base and from robot tool to robot wrist coordinate frames, are proposed. The presented methods introduce the Kronecker product and dual quaternions to solve the rotations and translations problem, simultaneously, with no propagation error. The experimental results in a simulated and a real environment are reported and analyzed. Key words: Hand/eye calibration, robot/world calibration, dual quaternion, Kronecker product.

Information and communication technology for participatory based decision-making-E-management for administrative efficiency in Higher Education

Abstract: Though many organizations have developed their own approaches in ensuring reliable decision making processes, not many have used technology to ensure effective participatory based decision making. This paper presents a model that incorporates reliable participatory based decision making practices and quality management indicators through strategic use of technology, an initiative of a faculty in a higher institution of learning. The model, called QuESt (Quality E-management System), integrates web-based technologies into an interconnected system to enable decision making by all stakeholders at multi levels of responsibility. Discussion in this paper is first focused on the bureaucracy and participatory models of decision making, then moves on to the research context, description of QuESt and discussion of the features and functions of the system. The paper concludes with an assessment of the potentialities of the system in taking an organization’s internal and external processes to the next level, using technology to ensure evidence based decision making, to interconnect staff roles and responsibilities and to use feedback to take appropriate action. Implications are drawn for knowledge advancement, policy making and practice. Key words: Participatory based decision making, E-management, accountability, efficiency, internal and external processes.

Preliminary phytochemical analysis and insecticidal activity of ethanolic extracts of four tropical plants (Vernonia amygdalina, Sida acuta, Ocimum gratissimum and Telfaria occidentalis) against beans weevil (Acanthscelides obtectus)

Abstract: Ethanolic extracts of the leaves of Ocimum gratissimum, Sida acuta, Telfaria occidentalis and Vernonia amygdalina were screened for secondary metabolite constituents and insecticidal activity against beans weevil (Acanthscelides obtectus). Phytochemical screening of the extracts revealed the presence of alkaloids, flavonoids, saponins, steroids, tannins, phlobatannins and terpenoids in the plants investigated. Phlobatannins and terpenoids were found to be absent in ethanol extract of T. occidentalis (leaf), saponins were also absent in both O. gratissimum and S. acuta while steroidal compounds were found to be absent inT. occidentalis and V. amygdalina (leaf). The extracts of O. gratissimum, S. acuta,T. occidentalis and V. amygdalina of different concentrations were also investigated for their insecticidal activity against A. obtectus. Average mortality indicated that the extracts caused significant mortality on the target insects. The bioassay has indicated that the toxic effect of the extracts was proportional to the concentration and higher concentration has stronger effect. The observed overall mean mortality also increased with increase in time intervals after treatment. The overall mean mortality at 0.25, 0.50, 0.75, 1.00 and 1.50 h after treatment (HAT) indicated that 4% solution of the extracts of V. amygdalina, S. acuta, O. gratissimum and T. occidentalis showed the highest mortality of 33.60, 31.47, 28.80 and 15.20, respectively in A. obtectus at 1.50 h after treatment. It could be inferred from the study that extract from V. amygdalina leaf could cause the highest significant mortality. Key words: Phytochemical, Ocimum gratissimum, Sida acuta, Telfaria occidentalis, Vernonia amygdalina.

Comparison of mechanical and bond properties of oil palm kernel shell concrete with normal weight concrete

Abstract: The comparison of the fresh, mechanical and bond properties of grade 30 lightweight concrete, namely oil palm kernel shell concrete (OPKSC) with normal weight concrete (NWC) of similar strength is presented in this paper. Oil palm kernel shell (OPKS), an industrial waste has been used as lightweight aggregates (LWA) in the OPKSC. In addition, mineral admixtures, 10% of silica fume and 5% fly ash have been used. The OPKSC produced a density reduction of about 20% compared to NWC. The addition of silica fume enhanced the compressive strength and thus OPKSC produced 28-day compressive strength up to 37 MPa. The bond stress of the OPKSC was found about 86% of the corresponding NWC; however, there was no slip failure between OPKSC and the reinforcement. Further, the ultimate experimental bond stress of OPKSC was found nearly 2Ω times higher than the theoretical values calculated based on BS standards.

An investigation on the concrete properties containing colemanite

Abstract: This article summarizes the results of an investigation on the effect of the colemanite on physical and mechanical properties of concrete using colemanite as replacement aggregate.

Purification and anti-fatigue activity of flavonoids from corn silk

Abstract: Flavonoids are major active ingredient in corn silk (CS) and possess various pharmacological activities. In this study, microporous resin adsorption technology was used for obtaining purified flavonoids from corn silk (FCS) and its anti-fatigue activity was evaluated. Eight kinds of macroporous resins with different properties were tested through static adsorption and one macroporous resin labeled as AB-8 was selected. Some important parameters were optimized for most effective enrichment and preparative separation. As follows: 1. for adsorption: sample solution FCS concentration was 2.636 mg/mL; processing volume was 4 BV; flow rate was 2 BV/h; temperature was 25°C; 2. for desorption: elution solvent ethanol-water (90%, v/v) solution was 4BV; flow rate was 1.0 BV/h. Flavonoids with content of 63.15% was obtained with a flavonoid recovery of 94.27% in the purification process. The results showed that AB-8 resin revealed a good ability to purify FCS. Swimming exercise results indicated that FCS had anti-fatigue activity of mice by inhibiting the production of blood lactic acid, retarding the formation of BUN and increasing hepatic glycogen concentration. Key words: Macroporous resins, purification, anti-fatigue activity, corn silk.

A survey on swarm intelligence based routing protocols in wireless sensor networks

Abstract: In the last decade, wireless sensor networks have attracted many researchers. One of the main topics adopted by researchers studying on wireless sensor networks is developing routing protocols for wireless systems. Routing protocol development deals with problems such as complexity, scalability, adaptability, survivability and battery life in wireless systems. Routing protocols grounded for wireless systems are developed in order to solve these problems. In this paper, we briefly discussed especially, swarm intelligence based routing protocols for wireless sensor networks. Key words:

Vehicle speed detection in video image sequences using CVS method

Abstract: Video and image processing has been used for traffic surveillance, analysis and monitoring of traffic conditions in many cities and urban areas. This paper aims to present another approach to estimate the vehicles velocity. In this study, the captured traffic movies are collected with a stationary camera which is mounted on a freeway. The camera was calibrated based on geometrical equations that were supported directly by using references. Camera calibration for exact measurements may be possible while accurate speed estimation can still be quite difficult to achieve. The designed system has the ability to be extended to another related traffic application. The average error of the detected vehicle speed was ± 7 km/h and the experiment was operated at different resolutions and different video sequences.

Reducing urban heat island effects: A systematic review to achieve energy consumption balance

Abstract: Considering the current energy consumption worldwide, it has become increasingly important to study the effects of urban heat island on energy consumption in order to improve the environment. This paper investigates the impact of Urban Heat Island (UHI) on energy consumption and also determines which factors can directly affect energy use in the city. The UHI current knowledge and literature are reviewed, as well as how UHI can affect energy consumption.This paper explores literally the conceptual framework of confliction between population and urban structure, which produce UHI intensity and affected energy consumption balance. It is then discussed how these two factors can be affected and gives implication to the city and then, focuses on whether actions should be taken for balancing adaptation and mitigation UHI effects. It will be concluded by making the three important strategies to minimise the impact of UHI on energy consumption: providing an appropriate landscape, using appropriate materials on external surfaces of buildings and urban areas and promoting natural ventilation. Key words: Energy consumption, quality of life, urban heat island, urban temperature.

Effect of aggregate size and proportion on strength properties of palm kernel shell concrete

Abstract: This paper presents information on the physical and mechanical properties of different sizes of palm kernel shells (PKS) used here as lightweight aggregates (LWA) and their influence on mechanical properties of palm kernel shell concrete (PKSC). Silica fume and fly ash were used as cementitious materials and all mixes had 1% superplasticizer on cement weight. It has been found that PKS consists of about 65 to 70% of medium size particles in the range of 5 to 10 mm. The other two sizes, namely, small (0-5 mm) and large (10-15 mm) sizes were found to influence the mechanical properties of PKSC. The 28-day compressive strengths were found in the range of 21 to 26 MPa. The concrete mix that was made with medium size PKS only produced lower compressive strength of about 11% compared to the mix that contained all sizes of PKS. However, the exclusion of medium size particles didn’t cause any segregation in the gap-graded aggregate concrete. The strength of PKS and bond governed the failure of PKSC. The flexural and splitting tensile strengths were found respectively 12 and 7% of the compressive strength. PKSC with about 70% of PKS of large size produced the highest modulus of elasticity of about 11 GPa.

Lineament mapping using multispectral remote sensing satellite data

Abstract: Accurate geological features mapping is critical task for oil exploration, groundwater storage and understanding the mechanisms of environmental disasters e.g., earthquake, flood and landslides. The main objective of this research is to design an automatic image processing tool for lineament mapping from remote sensing satellite data. In doing so, LANDSAT-TM satellite data of United Arab Emirates (UAE) is used. Further, three dimensional (3D) image reconstruction is generated using SRTM data. Then Canny algorithms is examined to determine an appropriate algorithm for lineaments automatic detection in LANDSAT-TM satellite data. The study shows that Canny algorithm provides perfect information about lineaments with 3D image visualization which is derived using SRTM. In conclusion 3D image visualization can provide excellent information about lineament and geological features from remote sensing satellite data.

Linking the balanced scorecard (BSC) to business management performance: A preliminary concept of fit theory for navigation science and management

Abstract: Natural oceanic phenomenon, such as internal waves and ocean currents, produce rapid environmental changes which can disrupt ocean-going mass transportation and shipping. The purpose of this study is to examine the relationship between ocean-induced environmental uncertainties and navigational business performance. A number of technical models, both numerical, regression and phenomenological, have already been identified as important tools for analyzing the effects of marine environmental change. It is therefore sufficient for us to further look at two constructs: information processing requirements and information processing capability, from the balanced scorecard (BSC) perspective in relation to empirical ocean study. In this study we explore the usefulness of the “Fit” model, in relation to environmental uncertainty, technical support and BSC performance. Previous research has proven that the BSC is a good tool for measuring and evaluating firm performance. The BSC makes it possible to evaluate managerial activities from a broad perspective, which can include both tangible financial aspects and intangible, non-financial aspects, for example when evaluating the integration of technology into a business. Customer satisfaction is at the core of business performance. The BSC is a goal and action-oriented approach that can monitor and improve business performance. The BSC was originally intended to solve problems related to the historical nature of the financial measures in accounting approaches. The “Fit” model can be viewed as a core construct for information processing related to business performance. Finding the best fit between the information processing requirements and the information processing capability needed to reach the best performance, has been the initial focus for organizational consideration. However, there is relatively little in the literature linking the fit model and the BSC. The purpose of this study is to make a contribution to this literature by focusing on a major issue that that has been relatively neglected: that is, the linking of the BSC to navigational business performance a preliminary concept of fit in the context of a marine environmental model. Key words: Balanced scorecard, navigation, business performance, regression model, conceptual framework.

Use of zeolite in maize (Zea mays) cultivation on nitrogen, potassium and phosphorus uptake and use efficiency.

Abstract: Concerns about unbalanced use of fertilizers leading to environmental pollution have been globally expressed. As a result, studies on how to use efficient methods to reduce nutrient applications at the same time increasing or maintaining crop yield, reducing nutrient losses and improving nutrient use efficiency are imperative. Nutrient loss due to leaching, volatilization and fixation upon fertilizer application to soils may be reduced through the use of slow-release fertilizers. A pot study was conducted to investigate if the use of inorganic fertilizers together with zeolite will improve nitrogen (N), phosphorus (P) and potassium (K) uptake and efficiency in maize (Zea mays) cultivation on Nyalau series (Typic Paleudalts). Maize hybrid no. 5 variety was used as test crop. Treatments evaluated were: (i) Unfertilized condition (T1), (ii) normal N, P and K application (7.4 g urea + 11.3 g Christmas Island rock phosphate (CIRP) + 3.8 g muriate of potash (MOP)) (T2), (iii) 135 g zeolite + 5.92 g urea+9.0 g CIRP + 3.0 g MOP (T3), (iv) 270 g zeolite + 4.44 g urea + 6.8 g CIRP + 2.3 g MOP (T4), (v) 405 g zeolite+3.0 g urea+4.5 g CIRP+1.5 g MOP (T5) and (vi) 540 g zeolite + 1.5 g urea + 2.3 g CIRP + 0.8 g MOP (T6). The effect of T2, T3, T4, T5 and T6 on soil N, P and Mg at harvest was not significantly different compared with T1. However, treatments with zeolite significantly increased K and Ca contents of soil compared to T1. Irrespective of treatment, dry matter production was not different. However, nutrient concentrations determined in plant tissues were clearly affected by the addition of zeolite. N, P and K uptake varied significantly but T6 significantly affected N, P and K use efficiency. The use of inorganic fertilizers mixed with zeolite remarkably increased N, P and K uptake, and their use efficiency in leaves, stem and roots. The use of zeolite could be beneficial with respect to nutrient retention in soil and their use efficiency.

Fatigue characteristics of stone mastic asphalt mix reinforced with fiber glass

Abstract: Asphalt modification/reinforcement has received considerable attention as viable solutions to enhance flexible pavement performance. This is mainly prompted by the unsatisfactory performance of traditional road materials exposed to dramatic increases and changes in traffic patterns. This paper presents the characteristics and properties of glass fiber reinforced Stone Mastic Asphalt. Laboratory tests were conducted to evaluate such related properties of asphalt mixture with different fiber contents. The tests undertaken comprise the Marshall test, indirect tensile test, creep test and fatigue test using repeated load indirect tensile test. The results showed that the addition of fiber does affect the properties of bituminous mixes, by decreasing its stability and increasing the voids in the mix. Stiffness properties of reinforced SMA mix were enhanced by about 12% as compared to control mix. Mixes with more than 0.2% fiber content exhibited lower resistance to permanent deformation. The results indicated that the fiber has the potential to resist structural distress that occur in road pavement as result of increased traffic loading, thus improving fatigue life by increasing the resistance to cracking and permanent deformation especially at higher stress level.

Evaluation of rainfall trends in Nigeria for 30 years (1978-2007)

Abstract: The issue of climate change appears to be on the fore burner and it cannot be ascertained to occur without evidence. Rainfall is one of the climatic factors that can indicate climate change. In this work, the non-parametric Mann-Kendall test is used to test for significant trend in rainfall in Nigeria through randomly selected locations in the six geopolitical zones within a 30 years period (1978-2007). The selected locations are; Maiduguri (13°10',11°50') in the North East, Kaduna (7°27',10°31') in the North West, Lokoja (6°45',7°43') in the North Central, Ibadan (3°53',7°22') in the South West, Enugu (7°30',6°27') in the South East and Calabar (8°28',4°57') in the South South. During the 30 years period, the yearly average rainfalls (mm) were 580.5, 1187.5, 1228.7, 1317.2, 1753.8 and 2925.6, respectively. While the rest of the locations had no significant trend yet Maiduguri showed an increasing trend at a rate of 9.88 mm/year, where formally the trend there from the period 1961-1990 was decreasing. This change could either be a problem or blessing to dwellers in that location and there is need for continuous monitoring. Key words: Mann-Kendall test, rainfall, significant trend, six geopolitical zones in Nigeria.

Correlation between electrical resistivity and soil-water content based artificial intelligent techniques

Abstract: By using an artificial intelligent approaches, the purpose of this study is to compare water content of soils obtained from electrical resistivity in order to better results from conventional techniques system. The input variables for this system are the electrical resistivity reading, the water content laboratory measurements. The output variable is water content of soils. In this study, 148 data sets are clustered into 120 training sets and 28 testing sets for constructing the fuzzy system and validating the ability of system prediction, respectively. Soil is a heterogeneous medium consisting of liquid, solid, and gaseous phases. The solid and liquid phases play an essential role in soil spontaneous electrical phenomena and in behavior of electrical fields, artificially created in soil. For our aim, study area is selected in Istanbul (Yesilkoy, Florya, Basinkoy) and Golcuk. In this area, the electrical resistivity is measured by VES (Vertical Electrical Sounding) in many points of these locations by field resistivity equipment. For geotechnical purposes, on the soil samples from borings, soil mechanics laboratory procedures was applied and it determined the soil water contents from these samples. Relationships between soil water content and electrical parameters were obtained by curvilinear models. The ranges of our samples are changed between 1 - 50 ohm.m (for resistivity) and 20 - 60 (%, for water content). For this range, it was found that classical regression relation between resistivity (R) and water content (W) of soils was W = 49.21e-0.017R. An artificial intelligent system (artificial neural networks, Fuzzy logic applications, Mamdani and Sugeno approaches) based on some comparisons about correlation between electrical resistivity and soil-water content, for Istanbul and Golcuk Soils in Turkey was constructed for identifying water content with electrical resistivity of soils. Key words: Soils, water content, electrical resistivity, artificial intelligent.

Considerations of the extraction process and potential technical applications of Nigerian rubber seed oil.

Abstract: Rubber seeds from the rubber tree (hevea brasiliensis) are in abundance in Nigeria from which nonedible oil could be obtained. However, the seeds are wasted in the rubber plantations annually even though the extractable oil has potential technical applications. If the full potentials of the oil are to be realized, there is need to have a data base information on the oil extraction process and its properties. Rubber seeds were collected from different rubber clones and extracted first by n-hexane to determine the yield characteristics. Second, the seeds were extracted by a hydraulic press at varied operating conditions: pressure range (5-8MPa), temperatures, 40-90oC; and moisture content, 7-16%. The effect of particle size and other operating variables on oil yield were studied. The physico-chemical properties of the extracted oil were evaluated. It was found that the percentage oil yield from the seeds of the rubber clone NIG800 at 45.03% was higher than the yield from other clones; GTI (40.21%) and RRIM 707 (38.42%) when the particle size of 1.16 mm was used. Oil yield increased with increase in temperature and pressure. Maximum oil yield was obtained during mechanical pressing at a moisture content of 10% (wt), temperature of 70oC and pressure of 8MPa. The physicochemical characteristics of the oil showed high incidence of free fatty acid (FFA) of 37.96% (wt) and the high iodine value (IV) of 142.45 is indicative of the presence of high unsaturation. Rubber seed oil could therefore serve as semi-drying oil used in ingredients for surface coating and in the formulation of products where the presence of unsaturation is important.

The effects of vortex finder on the pressure drop in cyclone separators

Abstract: In this study, three cylinder-shaped vortex finders with diameters of 80, 120 and 160 mm were designed and manufactured to find out the pressure drop of the cyclones by experimentally investigating the effects of gas inlet velocity, the vortex finder diameter and length on the cyclone performance at different gas concentration. As a result of this experimental analysis, a critical diameter of vortex finder is obtained as 120 mm. Furthermore, analyzing the experimental findings with a statistical regression method indicated that there was a linear relationship between length of vortex finder and pressure loss. Then, according to the analysis results, relevance values were obtained as 98.87, 98.37 and 97.59% for these vortex finders (with diameters of 80, 120 and 160 mm), respectively. Key words: Cyclone, vortex finder, pressure drop.

Use of vegetation for slope protection: Root mechanical properties of some tropical plants

Abstract: It is well documented that a bioengineering approach has recently regained a global recognition in preventing and controlling surface run-off, erosion and landslides. However, there is a lack of documentation on the root mechanical properties available especially in Malaysia. In this study, both pull-out and tensile strength of some tropical plants namely Leucaena leucocephala, Acacia mangium and Melastoma malabathricum is investigated on different stem sizes. Plots of pull-out capacity against displacement in L. leucocephala exhibit the presence of two peak values. Closer examination concludes that the first peak indicates the failure of the lateral roots and the second peaks is achieved when the tap roots failed. As for the tensile strength tests, results showed that the tensile strength decreases with increasing root diameter. The results also indicate that there is no correlation observed between the tensile strength, root length and root moisture content. Amongst the species, the highest root tensile strength was observed in L. leucocephala, followed by A. mangium and M. malabathricum. Thus, the study suggests that L. leucocephala is the best choice for slope stabilization work as it exhibits outstanding root mechanical properties.

Overview of textual anti-spam filtering techniques

Abstract: Elecronic mail (E-mail) is an essential communication tool that has been greatly abused by spammers to disseminate unwanted information (messages) and spread malicious contents to Internet users. Current Internet technologies further accelerated the distribution of spam. Effective controls need to be deployed to countermeasure the ever growing spam problem. Machine learning provides better protective mechanisms that are able to control spam. This paper summarizes most common techniques used for anti-spam filtering by analyzing the e-mail content and also looks into machine learning algorithms such as Naive Bayesian, support vector machine and neural network that have been adopted to detect and control spam. Each machine learning has its own strengths and limitations as such appropriate preprocessing need to be carefully considered to increase the effectiveness of any given machine learning. Key words: Anti-spam filters, text categorization, electronic mail (E-mail), machine learning.

Influence of ZnO on the ultrasonic velocity and elastic moduli of soda lime silicate glasses

Abstract: The effects of ZnO on longitudinal and transverse ultrasonic wave velocities of soda lime silicate (SLS) glasses have been measured using the pulse-echo method at 5 MHz frequency at room temperature. The elastic properties: Longitudinal modulus, shear modulus, Young’s modulus, bulk modulus, Poisson’s ratio, and Debye temperature are found to be rather sensitive to the glass composition. Experiments showed that these parameters depend upon the ZnO-modifier content. Key words: Glasses, annealing, ultrasonic measurements, elastic properties.

Heavy metals in water springs of the Yarmouk Basin, North Jordan and their potentiality in health risk assessment

Abstract: The objective of this study is to determine the seasonal water quality variations of the major springs of the Yarmouk Basin of North Jordan. A total of 36 water samples were collected in October 2006 (dry season) and in May 2007 (wet season) and analyzed for temperature, electrical conductivity, total dissolved solids, pH, Pb, Cd, Zn, Cu, Mn and Fe. The pH was found near alkaline ranging from 7.01 7.87 and 6.8 8.04 for the pre and post-wet season water samples, respectively. Electrical conductivity varied from 300 to 1199 μS/cm and from 424 to 962 μS/ cm for the dry and wet season water samples, respectively. The results of heavy metals analysis indicated that some water samples exceeded the Jordanian. Overall, the results showed that the water springs of the Yarmouk Basin in North Jordan are contaminated with heavy metals that might affect human health as well as the health of the ecosystem.