Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
Impact of the salinity gradient on the mollusc fauna in flooded mine subsiden...EdytaSierka
Archives of Environmental Protection, 2014
This paper presents the impact of salinisation on the aquatic mollusc fauna in fl ooded mine subsidences in the Karvina region (Czech Republic). The results of the previous research on salinity in fl ooded mine subsidences show that some of them contain a high content of dissolved inorganic substances (above 1000 mg•l-1). These substances can affect the vegetation and animals occurring in the water and the surrounding area. The phylum of Mollusca was selected as a model group for the fi eldwork as it includes species with the proven bioindication potential. The occurrence of aquatic mollusc species was studied at 10 sites. The sites were selected based on the content of dissolved substances (the salinity gradient from <500 to >1000 mg•l-1. A total of 12 aquatic mollusc species were found, including one species identifi ed as a potential bioindicator of the negative effect of salinisation on aquatic biota. The analysis showed statistically signifi cant positive correlations between the content of dissolved inorganic substances and the presence of alien species Potamopyrgus antipodarum (J.E. Gray, 1843). The gradient of salinity signifi cantly affects the species composition of the mollusc fauna in fl ooded mine subsidences and may affect the biodiversity of this group.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Impact of the salinity gradient on the mollusc fauna in flooded mine subsiden...EdytaSierka
Archives of Environmental Protection, 2014
This paper presents the impact of salinisation on the aquatic mollusc fauna in fl ooded mine subsidences in the Karvina region (Czech Republic). The results of the previous research on salinity in fl ooded mine subsidences show that some of them contain a high content of dissolved inorganic substances (above 1000 mg•l-1). These substances can affect the vegetation and animals occurring in the water and the surrounding area. The phylum of Mollusca was selected as a model group for the fi eldwork as it includes species with the proven bioindication potential. The occurrence of aquatic mollusc species was studied at 10 sites. The sites were selected based on the content of dissolved substances (the salinity gradient from <500 to >1000 mg•l-1. A total of 12 aquatic mollusc species were found, including one species identifi ed as a potential bioindicator of the negative effect of salinisation on aquatic biota. The analysis showed statistically signifi cant positive correlations between the content of dissolved inorganic substances and the presence of alien species Potamopyrgus antipodarum (J.E. Gray, 1843). The gradient of salinity signifi cantly affects the species composition of the mollusc fauna in fl ooded mine subsidences and may affect the biodiversity of this group.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
The International Journal of Engineering and Science (The IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Hydrochemical Characteristics and Shallow Groundwater Quality in Kirkuk Urban...Agriculture Journal IJOEAR
Abstract— The assessment of hydrochemical characteristics and shallow groundwater quality was carried out in Kirkuk urban area, Iraq. Twenty two water samples were collected systematically at 20 locations for each of high and low water seasons in April and September (2014) and analysed for physical and chemical parameters. Hydrochmical data suggest that contamination of ground water is caused by infiltration of surface water polluted by domestic seepage pits and leakage from local agricultural area. Depending on hydrochemical facies, the type of water that predominates in the urban area is Ca-Mg-SO4 type during both wet and dry seasons. The study found that Kirkuk shallow groundwater is unsuitable for drinking water and industries purposes but some of water samples are suitable for construction and irrigation purposes.
Assessment of the Water Quality of Lake Sidi Boughaba (Ramsar Site 1980) Keni...journal ijrtem
Sidi Boughaba Lake, part of a wetland complex of Morocco (Ramsar site in 1980) is located on
the Atlantic coast of northwestern Morocco, oriented NNE - SSW and located in an interdunal depression. The
existence of this body of water is due to the fact that the topographic surface is at a lower cost than that of the
piezometric surface of the coastal water table, rainwater and runoff water. The objective of this study is to
determine the physical and chemical characteristics of the waters of this lake. Thus, several water samples were
taken monthly in the period 2016-2017. Parameters such as: temperature, pH, electrical conductivity (EC),
chloride (Cl-
), turbidity (NTU), calcium (Ca2+) and magnesium (Mg2+). The results obtained show that the
distribution of the analyzed elements in Lake waters is quite variable between seasons, as well as between stations.
However, the analysis showed that the studied waters are very mineralized, with an EC between 7 g/l and 14.8
g/l. This mineralization is essentially evaporitic and is controlled by various processes, such as evaporation and
marine influence by aerosol.
Assessment of the Water Quality of Lake Sidi Boughaba (Ramsar Site 1980) Keni...IJRTEMJOURNAL
Sidi Boughaba Lake, part of a wetland complex of Morocco (Ramsar site in 1980) is located on
the Atlantic coast of northwestern Morocco, oriented NNE - SSW and located in an interdunal depression. The
existence of this body of water is due to the fact that the topographic surface is at a lower cost than that of the
piezometric surface of the coastal water table, rainwater and runoff water. The objective of this study is to
determine the physical and chemical characteristics of the waters of this lake. Thus, several water samples were
taken monthly in the period 2016-2017. Parameters such as: temperature, pH, electrical conductivity (EC),
chloride (Cl-
), turbidity (NTU), calcium (Ca2+) and magnesium (Mg2+). The results obtained show that the
distribution of the analyzed elements in Lake waters is quite variable between seasons, as well as between
stations. However, the analysis showed that the studied waters are very mineralized, with an EC between 7 g/l
and 14.8 g/l. This mineralization is essentially evaporitic and is controlled by various processes, such as
evaporation and marine influence by aerosol.
Abstract : Relationship of qualitative and quantitative fisheries diversity with the environmental variables was studied for the period of two years along the three zones, viz. upper, middle and lower, of the Ulhas River estuary. Total ten hydro-sedimentological parameters were analyzed on monthly basis from each zone to depict ambient pollution level. Zones with comparatively higher pollution level deterred fisheries landings. The principal coordination analysis (PCO) ordination and zonewise K-dominance curves revealed the direct correlation of fish diversity with the existent spatial environmental conditions of the Ulhas River estuary.
Ulhas River estuary has been polluted due to several anthropogenic activities in the nearby urban and industrial areas viz. Thane, Dombivli, Kalyan, Mumbra, Biwandi and Mira-Bhayander. the anthropogenic activities like sewage water and industrial effluent influx, agricultural fields, sand excavation, solid waste dumping has put tremendous pressure on the inhabitant fish species from the ambient water. Mudskippers were not the exception during the present study. The species like Boleophthalmus dussumieiri (Cuv. & Val.) fishery had dwindled to a threatened limit during the study. It was envisage to analyse the water quality through hydrological study and its impact on fishery of Boleophthalmus dussumieiri in the Ulhas River estuary.
The peer-reviewed International Journal of Engineering Inventions (IJEI) is started with a mission to encourage contribution to research in Science and Technology. Encourage and motivate researchers in challenging areas of Sciences and Technology.
A REVIEW ARTICLE ON IMPACT OF URBANIZATION ON HYDROLOGICAL PARAMETERS IAEME Publication
As longas human being continues to exists,urbanization continues. Urbanizationhasa direct effect on environment which in turn effects the variations in hydrology. It may results from changes inthe land use pattern to built-up areas resulting in runoff which ultimately leads to flood. Most of the studies revealed thatland use pattern has drastically changed in whichthe builtup area increases year after year.The land use land cover changes can be identified using GIS. Many researchers have found that urbanization has an impact on hydrological parameters such as runoff volume, discharge in drains, infiltration, interception, evapotranspiration etc. An attempt has been made to consolidate the review of literature related to impact of urbanization on hydrological parameters.
Water Quality Assessment of El-Salam Canal (Egypt) Based on Physico-Chemical ...Premier Publishers
Water quality of El-Salam Canal was assessed using physico-chemical and certain biological characteristics. Downstream increase of total soluble inorganic nitrogen (TSIN) and dissolved reactive phosphorus (DRP) indicated increasing downstream eutrophication. The significant (P ≤ 0.01) downstream increase of chloride indicated elevated pollution. Water quality index (WQI) down (53) and up-stream (48) stations indicated bad to moderate condition, respectively. The increase of N, P, heavy metals and WQI may be attributed to excessive input of wastewater from El-Serw and Hadous drains. The highest concentrations of Fe (0.138 mg/l), Mn (0.116), Zn (0.057), Cu (0.019), Pb (0.278) and Cd (0.016) were recorded at downstream stations. Accumulation of these metals by hydrophytes followed the order: Fe ˃ Mn ˃ Zn ˃ Cu ˃ Pb ˃ Cd. Fifteen different hydrophytes were recorded with marked decline in species richness during winter and at downstream stations. The epiphytic microalgae were represented by 50 different taxa, belonging to six phylla including Cyanobacteria, Chlorophyta, Charophyta, Bacillariophyta, Euglenophyta and Rhodophyta. Thespecies composition and richness of the epiphytic microalgae was largely influenced by the plant species, as the highest number of species (42 taxa) was recorded for Ceratophyllum demersum and the lowest one (31 taxa) for Phragmites australis.
This ppt covers sources, natural and anthropogenic processes, and impacts of heavy metals pollution on environment with Mechanisms of Remediating Heavy Metals.
The International Journal of Engineering and Science (The IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Hydrochemical Characteristics and Shallow Groundwater Quality in Kirkuk Urban...Agriculture Journal IJOEAR
Abstract— The assessment of hydrochemical characteristics and shallow groundwater quality was carried out in Kirkuk urban area, Iraq. Twenty two water samples were collected systematically at 20 locations for each of high and low water seasons in April and September (2014) and analysed for physical and chemical parameters. Hydrochmical data suggest that contamination of ground water is caused by infiltration of surface water polluted by domestic seepage pits and leakage from local agricultural area. Depending on hydrochemical facies, the type of water that predominates in the urban area is Ca-Mg-SO4 type during both wet and dry seasons. The study found that Kirkuk shallow groundwater is unsuitable for drinking water and industries purposes but some of water samples are suitable for construction and irrigation purposes.
Assessment of the Water Quality of Lake Sidi Boughaba (Ramsar Site 1980) Keni...journal ijrtem
Sidi Boughaba Lake, part of a wetland complex of Morocco (Ramsar site in 1980) is located on
the Atlantic coast of northwestern Morocco, oriented NNE - SSW and located in an interdunal depression. The
existence of this body of water is due to the fact that the topographic surface is at a lower cost than that of the
piezometric surface of the coastal water table, rainwater and runoff water. The objective of this study is to
determine the physical and chemical characteristics of the waters of this lake. Thus, several water samples were
taken monthly in the period 2016-2017. Parameters such as: temperature, pH, electrical conductivity (EC),
chloride (Cl-
), turbidity (NTU), calcium (Ca2+) and magnesium (Mg2+). The results obtained show that the
distribution of the analyzed elements in Lake waters is quite variable between seasons, as well as between stations.
However, the analysis showed that the studied waters are very mineralized, with an EC between 7 g/l and 14.8
g/l. This mineralization is essentially evaporitic and is controlled by various processes, such as evaporation and
marine influence by aerosol.
Assessment of the Water Quality of Lake Sidi Boughaba (Ramsar Site 1980) Keni...IJRTEMJOURNAL
Sidi Boughaba Lake, part of a wetland complex of Morocco (Ramsar site in 1980) is located on
the Atlantic coast of northwestern Morocco, oriented NNE - SSW and located in an interdunal depression. The
existence of this body of water is due to the fact that the topographic surface is at a lower cost than that of the
piezometric surface of the coastal water table, rainwater and runoff water. The objective of this study is to
determine the physical and chemical characteristics of the waters of this lake. Thus, several water samples were
taken monthly in the period 2016-2017. Parameters such as: temperature, pH, electrical conductivity (EC),
chloride (Cl-
), turbidity (NTU), calcium (Ca2+) and magnesium (Mg2+). The results obtained show that the
distribution of the analyzed elements in Lake waters is quite variable between seasons, as well as between
stations. However, the analysis showed that the studied waters are very mineralized, with an EC between 7 g/l
and 14.8 g/l. This mineralization is essentially evaporitic and is controlled by various processes, such as
evaporation and marine influence by aerosol.
Abstract : Relationship of qualitative and quantitative fisheries diversity with the environmental variables was studied for the period of two years along the three zones, viz. upper, middle and lower, of the Ulhas River estuary. Total ten hydro-sedimentological parameters were analyzed on monthly basis from each zone to depict ambient pollution level. Zones with comparatively higher pollution level deterred fisheries landings. The principal coordination analysis (PCO) ordination and zonewise K-dominance curves revealed the direct correlation of fish diversity with the existent spatial environmental conditions of the Ulhas River estuary.
Ulhas River estuary has been polluted due to several anthropogenic activities in the nearby urban and industrial areas viz. Thane, Dombivli, Kalyan, Mumbra, Biwandi and Mira-Bhayander. the anthropogenic activities like sewage water and industrial effluent influx, agricultural fields, sand excavation, solid waste dumping has put tremendous pressure on the inhabitant fish species from the ambient water. Mudskippers were not the exception during the present study. The species like Boleophthalmus dussumieiri (Cuv. & Val.) fishery had dwindled to a threatened limit during the study. It was envisage to analyse the water quality through hydrological study and its impact on fishery of Boleophthalmus dussumieiri in the Ulhas River estuary.
The peer-reviewed International Journal of Engineering Inventions (IJEI) is started with a mission to encourage contribution to research in Science and Technology. Encourage and motivate researchers in challenging areas of Sciences and Technology.
A REVIEW ARTICLE ON IMPACT OF URBANIZATION ON HYDROLOGICAL PARAMETERS IAEME Publication
As longas human being continues to exists,urbanization continues. Urbanizationhasa direct effect on environment which in turn effects the variations in hydrology. It may results from changes inthe land use pattern to built-up areas resulting in runoff which ultimately leads to flood. Most of the studies revealed thatland use pattern has drastically changed in whichthe builtup area increases year after year.The land use land cover changes can be identified using GIS. Many researchers have found that urbanization has an impact on hydrological parameters such as runoff volume, discharge in drains, infiltration, interception, evapotranspiration etc. An attempt has been made to consolidate the review of literature related to impact of urbanization on hydrological parameters.
Water Quality Assessment of El-Salam Canal (Egypt) Based on Physico-Chemical ...Premier Publishers
Water quality of El-Salam Canal was assessed using physico-chemical and certain biological characteristics. Downstream increase of total soluble inorganic nitrogen (TSIN) and dissolved reactive phosphorus (DRP) indicated increasing downstream eutrophication. The significant (P ≤ 0.01) downstream increase of chloride indicated elevated pollution. Water quality index (WQI) down (53) and up-stream (48) stations indicated bad to moderate condition, respectively. The increase of N, P, heavy metals and WQI may be attributed to excessive input of wastewater from El-Serw and Hadous drains. The highest concentrations of Fe (0.138 mg/l), Mn (0.116), Zn (0.057), Cu (0.019), Pb (0.278) and Cd (0.016) were recorded at downstream stations. Accumulation of these metals by hydrophytes followed the order: Fe ˃ Mn ˃ Zn ˃ Cu ˃ Pb ˃ Cd. Fifteen different hydrophytes were recorded with marked decline in species richness during winter and at downstream stations. The epiphytic microalgae were represented by 50 different taxa, belonging to six phylla including Cyanobacteria, Chlorophyta, Charophyta, Bacillariophyta, Euglenophyta and Rhodophyta. Thespecies composition and richness of the epiphytic microalgae was largely influenced by the plant species, as the highest number of species (42 taxa) was recorded for Ceratophyllum demersum and the lowest one (31 taxa) for Phragmites australis.
This ppt covers sources, natural and anthropogenic processes, and impacts of heavy metals pollution on environment with Mechanisms of Remediating Heavy Metals.
The metals, which are required in a very minute amount and are considered toxic, are
termed as heavy metals. Researchers have widely investigated and studied these metals
due to their dangerous and harmful influence on health and the environment. Due to their
ability to accumulate and toxic nature these are addressed to be a vital source of environmental
contamination. Heavy metals have critically polluted the environment and its components.
This has severely damaged its abilities to promote life and provide its intrinsic
values. These are naturally available compounds and because of their anthropogenic origin
they are commonly found in various environmental domain. This results in deterioration of
the environment competence to support life and health of human, animals and plants
becomes threatened. This takes place because of bioaccumulation of these heavy metals in
the food chain which is a direct consequence of nondegradable state of the heavy metals.
The surroundings within which the human life exists is referred as the environment. It basically
comprises of the water, land, microorganisms, animal and plant life and the atmosphere
of the earth.
When the water is good, it can be used by all. When it is polluted, it becomes unsuitable for any purpose. Even a small amount of pollutant while mixing with the water resources will contaminate the whole resource. This module highlights the problems of pollution and their effects in water resources.
Experimental Investigation of a Household Refrigerator Using Evaporative-Cool...inventy
The objective of this paper was to investigate experimentally the effect of Evaporative-cooled condenser in a household refrigerator. The experiment was done using HCF134a as the refrigerant. The performance of the household refrigerator with air-cooled and Evaporative-cooled condenser was compared for different load conditions. The results indicate that the refrigerator performance had improved when evaporative-cooled condenser was used instead of air-cooled condenser on all load conditions. Evaporativecooled condenser reduced the energy consumption when compared with the air-cooled condenser. There was also an enhancement in coefficient of performance (COP) when evaporative-cooled condenser was used instead of air-cooled condenser. The Evaporative cooled heat exchanger was designed and the system was modified by retrofitting it, instead of the conventional air-cooled condenser by making drop wise condensation using water and forced circulation over the condenser. From the experimental analysis it is observed that the COP of evaporative cooled system increased by 13.44% compared to that of air cooled system. So the overall efficiency and refrigerating effect is increased. In minimum constructional, maintenance and running cost, the system is much useful for domestic purpose. This study also revealed that combining a evaporative cooled system along with conventional water cooled system under the condition that the defrost water obtained from the freezer is used for drop wise condensation over condenser and water cooled condensation of the condenser at the bottom using remaining defrost water would reduce the power consumption, work done and hence further increase in refrigerating effect of the system. The study has shown that such a system is technically feasible and economically viable
Copper Strip Corrossion Test in Various Aviation Fuelsinventy
This research work takes in to account of corrosiveness test on various aviation fuels in the state of Telengana (India). The purpose of this experiment is to determine the corrosiveness test of fuels. This determination will be accomplished by using copper strip corrosion test by using the copper strip experiment we can determine the corrosive property of the fuel and hence the efficiency of fuel. The research covers the importance of knowing the corrosive property of different petroleum fuels including aviation turbine fuel.
Additional Conservation Laws for Two-Velocity Hydrodynamics Equations with th...inventy
A series of the differential identities connecting velocities, pressure and body force in the twovelocity hydrodynamics equations with equilibrium of pressure phases in reversible hydrodynamic approximation is obtaned.
Comparative Study of the Quality of Life, Quality of Work Life and Organisati...inventy
People’s lives are increasingly centred on work; they spend at least one-third of their time within the organisations that employ them. Investigating the factors that interfere with employees’ well-being and the organisational environment is becoming an increasing concern in organisations. This article identifies the criteria of the quality of life (QoL), quality of working life (QWL) and organisational climate instruments to point out their similarities. For bibliographic construction and data research, articles were sought in national and international journals, books and dissertations/articles in SciELO, Science Direct, Medline and Pub Med databases. The results show direct relationships amongst QoL, QWL and organisational climate instruments. The relationship between QoL and QWL instruments is based on fair compensation, social interaction, organisational communication, working conditions and functional capacity. QWL and organisational climate instruments are related through social interaction and interfaces. QoL and organisational climate instruments are related based on social interaction, organisational communication, and work conditions.
A Study of Automated Decision Making Systemsinventy
The decision making process of many operations are dependent on analysing very large data sets, previous decisions and their results. The information generated from the large data sets are used as an input for making decisions. Since the decisions to be taken in day to day operations are expanding, the time taken for manual decision making is also expanding. In order to reduce the time, cost and to increase the efficiency and accuracy, which are the most important things for customer satisfaction, many organisations are adopting the automated decision making systems. This paper is about the technologies used for automated decision making systems and the areas in which automated decisions systems works more efficiently and accurately.
Crystallization of L-Glutamic Acid: Mechanism of Heterogeneous β -Form Nuclea...inventy
The mechanism of heterogeneous nucleation of β-form L-glutamic acid was deeply investigated in cooling crystallization. The present study found that the β-form crystals were epitaxially grown on the α-form crystals and they were preferably crystallized on the (011) and (001) surfaces instead of the (111) surfaces of α- form crystals. This result was explained via the molecular simulation. The molecular simulation indicated that the different surfaces of α-form crystals provided different functional groups, resulting in different sites for the heterogeneous nucleation of β-form crystals. Here, the functional group were COO- , C=O and O-H on the (011) and (001) surfaces of α-form crystals, respectively, while it was the NH3 + on the (111) surfaces of α-form crystals. As such, the degree of lattice matching (E) between the β-form crystals and the various surfaces of α- form crystal was distinguished, where the degree of lattice matching (E) between the β-form crystals and the (011), (001) and (111) surfaces of α-form crystal were estimated as 5.30, 5.25 and 2.39, respectively, implying that the (011) and (001) surfaces of α-form crystal were more favorable to generate the heterogeneous nucleation of β-form crystals than the (111) surfaces of α-form crystal
Evaluation of Damage by the Reliability of the Traction Test on Polymer Test ...inventy
In recent decades, polymers have undergone a remarkable historical development and their use has been greatly imposed by gradually dethroning most of the secular materials. These polymer materials have always distinguished themselves by their simple shaping and inexpensive price, their versatility, lightness, and chemical stability but despite their massive use in everyday life as well as in advanced technologies. Generally, these materials still not understood which requires a thorough knowledge of their chemical, physical, rheological and mechanical properties. This paper, we study the mechanical behavior of an amorphous polymer: Acrylonitrile Butadiene Styrene “ABS” by means of uniaxial tensile testing on pierced test pieces with different notch lengths ranging between 1 to 14mm.The proposed approach consists in analyzing the evolution of the global geometry of the obtained strain curves by taking into account the zones and characteristic points of these curves as well as the effect of the damage on the mechanical behavior of the polymer ABS, in order to visualize the evolution of the damage by a static model
Application of Kennelly’model of Running Performances to Elite Endurance Runn...inventy
: The model of Kennelly between distance (Dlim) and exhaustion time (tlim) has been applied to the individual performances of 19 elite endurance runners (World-record holders and Olympic winners) from P. Nurmi (1920-1924) to M. Farah (2012) whose individual best performances on several different distances are known. Kennelly’s model (Dlim = k tlim ) can describe the individual performances of elite runners with a high accuracy (errors lower than 2 %). There is a linear relationship between parameters k and exponents of the elite runners and the extreme values correspond to S. Coe (k = 15.8; = 0.851) and E. Zatopek (k = 6.57; = 0.984). Exponent can be considered as a dimensionless index of aerobic endurance which is close to 1 in the best endurance runners. If it is assumed than maximal aerobic speed can be maintained 7 min in elite endurance runners, exponent is equal to the normalized critical speed (critical speed/maximal aerobic speed) computed from exhaustion times equal to 3 and 12.5 min in these runners.
Development and Application of a Failure Monitoring System by Using the Vibra...inventy
In this project, a failure monitoring system is developed by using the vibration and location information of balises in railway signaling. A lot of field equipment in railway are loosening and broken in time period so that they need maintenance due to the vibrations that occur due to high speed trains traffic and railway vehicles impact. Among the field equipment, balises have very important role of communication in terms of transmitting information to trains. In this scope, it is aimed to make maintenance works more efficient, have no delayed trains, detect previously failure location and intervene in failure timely, by detecting and controlling balise cases such as loosening, out of place and the data consistency error that happens because of balise physical state. In this project, the communication is provided with I2C, Modbus RTU (Remote Terminal Unit) and RS485 standards by using Arduino Uno cards and MPU6050 IMU (Inertial Measurement Unit) sensors in laboratory. Each used sensors are in slave mode and computer interface designed with C# is in master mode. Fault situations in the system are checked instant by the interface. (it is assumed to mount the IMU sensor and the Arduino circuit on the balise) it is seen that the interface responds to the sensor movements instant and the system works well in the end of test processes.
The Management of Protected Areas in Serengeti Ecosystem: A Case Study of Iko...inventy
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Removal of Chromium (VI) From Aqueous Solutions Using Discarded Solanum Tuber...inventy
Industrial polluting effluents containing heavy metals are of serious environmental concern in India. Chromium is frequently used in industries like electroplating, metal finishing, cooling towers, dyes, paints, anodizing and leather tanning and is found as traces in effluents finding their way to natural water bodies causing hazardous toxicity to the health of humans, animals and aquatic lives directly or indirectly. Many methods for the removal of Chromium such as chemical reduction, precipitation, ion exchange, electrochemical reduction, evaporation, reverse osmosis and adsorption using activated carbon etc. have been reported but all being expensive and complicated to operate. Experimental practices reveal that adsorption by agricultural and horticultural wastes are quite simple, inexpensive and efficient method. Agra is famous for Potato farming, a lot of discarded potato waste from cold storages is thrown along road side drains causing solid waste generated which either creates solid waste disposal problem or otherwise it finds way to Yamuna river resulting high BOD and posing a serious threat to the aquatic environment. For developing countries like India adsorption studies using discarded potato (Solanum tuberosum) waste from cold storages (DPWC) a solid waste as low cost adsorbent for Chromium removal was dual beneficial i.e., an ideal solution to these solid wastes disposal problem of Agra and removal of Chromium from tannery effluents and thereby saving aquatic life from Chromium contamination in Yamuna river. Keeping this in view batch experiments were designed to study the feasibility of discarded potato waste from cold storages to remove chromium (VI) from the aqueous solutions. During the study various affecting parameters, such as pH, adsorbent does, initial concentration, temperature, contact time, adsorbent grain size and start up agitation speed were optimized as 5.0, 10-20 g/l, 50 mg/l, 250C, 135 minutes, average size and 80 rpm respectively on chromium removal efficiency. Various Isotherms such as Langmuir, Freundlich, Tempkin also fitted suitably and various corresponding constants determined from these Isotherms favor and support the adsorption. Thermodynamic constants ∆G, ∆H and ∆S were found to be 0.267 KJ/mole, 0.288 KJ/mole and 0.0013 KJ/mole respectively.
Effect of Various External and Internal Factors on the Carrier Mobility in n-...inventy
The effect of various external (temperature, electric field, light) and intracrystalline (doping, initial resistivity) factors on the mobility of carriers in layered n-InSe semiconductor experimentally have been investigated. Scientific explanations of the results are proposed
Transient flow analysis for horizontal axial upper-wind turbineinventy
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Choice of Numerical Integration Method for Wind Time History Analysis of Tall...inventy
Wind tunnel tests are being performed routinely around the world for designing tall buildings but the advent of powerful computational tools will make time-history analysis for wind more common in near future. As the duration of wind storms ranges from tens of minutes to hours while earthquake durations are typically less than a three to four minutes, the choice of a time step size (Δt) for wind studies needs to be much larger both to reduce the computational time and to save disk space. As the error in any numerical solution of the equation of motion is dependent on step size (Δt), careful investigations on the choice of numerical integration methods for wind analyses are necessary. From a wide variety of integration methods available, it was decided to investigate three methods that seem appropriate for 3D-time history analysis of tall buildings for wind. These are modal time history analysis, the Hilber-Hughes-Taylor (HHT) method or α-method with α=- 0.1, and the Newmark method with β=0.25 and γ=0.5 ( i.e., trapezoidal rule). SAP2000, a common structural analysis software tool, and a 64-story structure are used to conduct all the analyses in this paper. A boundary layer wind tunnel (BLWT) pressure time history measured at 120 locations around the building envelope of a similar structure is used for the analyses. Analyses performed with both the HHT and Newmark-method considering P-delta effects show that second order effects have a considerable impact on both displacement and acceleration response. This result shows that it is necessary to account P-delta effect for wind analysis of tall buildings. As the direct integration time history analysis required very large computation times and very large computer physical memory for a wind duration of hours, a modal analysis with reduced stiffness is considered as a good alternative. For that purpose, a non-linear static analysis of the structure with a load combination of 1.0D + 1.0L is performed in SAP2000 and the reduced stiffness of the structure after the analysis is used to conduct an eigenvalue analysis to extract the mode shapes and frequencies of this structure. Then the first 20- modes are used to perform a modal time history analysis for wind load. The result shows that the responses from modal analysis with “20-mode (reduced stiffness)” are comparable with that from the P-Δ analyses of Newmark-method
Impacts of Demand Side Management on System Reliability Evaluationinventy
Electricity demand in Saudi Arabia is steadily increasing as electrical loads grows at a rate of about 7% per year, this represents a high rate by all standards, and largely due to population growth, as well as due to government subsidies which may lead to prices much lower than actual production cost. This growth represents a challenge that requires Saudi Electricity Company (SEC) to invest huge amounts of money every year, for the construction of additional generation capacity along with the reinforcement of transmission network to meet the consumption growth.Also the demand varies frequently throughout the day, causing a waste of a large part of the energy. SEC believes the optimum solution lies in altering the load shape in order to have a better balance between customer’s consumption and SEC’s generation, This paper describes the method for improving the power system reliability by shifting the portion of peak load to off-peak periods This load management scheme can be achieved by lifting the generation during off peak periods and utilizing the stored energy during peak periods. A hybrid set up involving solar and wind energy along with batteries can also be used to store energy and utilize it during peak periods.
Reliability Evaluation of Riyadh System Incorporating Renewable Generationinventy
In this paper, the experience of Saudi Electricity Company (SEC) in analyzing the generation adequacy for Year 2013 is presented. This analysis is conducted by calculating several reliability indices for Riyadh system hourly load during all four seasonal periods. The reliability indices are gauged against the international utility practice. SEC also plans to introduce renewable energy into the network in order to secure the environmental standards and reduce fuel costs of conventional generation. Thus, the reliability improvement due to different integration levels of Solar and Wind generating sources has also been investigated. The capacity value provided by these variable renewable energy sources (VERs) to reliably meet the system load has been calculated using effective load carrying capability (ELCC) technique with a loss of load expectancy metric.
The effect of reduced pressure acetylene plasma treatment on physical charact...inventy
The capacitors are increasingly being used as energy storage devicesin various power systems. The scientists of the world are tryingto maximize the electrical capacity of the supercapacitors. To achieve this purpose, numerous method sare used: the surface activation of electrodes, the surface etching using the electronbeam, the electrode etching with variousgasplasma, etc. The purpose of this work is toresearch how the properties of carbon electrodes depend on the plasma parameters at whichtheywere formed. The largest surface area ofcarbonelectrodeof47.25m2 /gis obtainedat 15 ofAr/C2H2gasratio. Meanwhile, theSEMimages show that the disruption of structures with low bond energies and the formation of new onesare taking place when the carbon electrodes are etched at acetylene plasma and placed on carbon electrode. The measurements of capacitance showthat capacitors with affectedelectrodes have about10-15% highercapacity than those not treated with acetyleneplasma.
Experimental Investigation of Mini Cooler cum Freezerinventy
In general cases the refrigerator could be converted into an air conditioner by attaching a fan. Thus a cooler as well as freezer is obtained in a single set up. The freezer can be converted to an air conditioner when the outside air is allowed to flow beside the cooling coil and is forced outside by an exhaust fan. In this case a mini scale cooler cum freezer using R134a as refrigerant was fabricated and tested In our mini project work we had designed, fabricated and experimentally analysed a mini cooler cum freezer. From the observations and calculations, the results of mini cooler cum freezer are obtained and are compared.
Growth and Magnetic properties of MnGeP2 thin filmsinventy
We have successfully grown MnGeP2 thin films on GaAs (100) substrate. A ferromagnetic transition near 320 K has been observed by temperature dependent magnetization and resistance measurements. Field dependent magnetization experiments have shown that the coercive fields at 5, 250, and 300 K are 3870, 1380 and 155 Oe, respectively. Magnetoresistance and Hall measurements have displayed that hole conduction is dominant in MnGeP2. PACS: 75.50.Pp, 75.70.-i, 85.70.-w, 73.50.-h
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
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Generating a custom Ruby SDK for your web service or Rails API using Smithyg2nightmarescribd
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Connector Corner: Automate dynamic content and events by pushing a buttonDianaGray10
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Create a campaign using Mailchimp with merge tags/fields
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In a second workflow supporting the same use case, you’ll see:
Your campaign sent to target colleagues for approval
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And...
Speakers:
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The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
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Builder.ai Founder Sachin Dev Duggal's Strategic Approach to Create an Innova...Ramesh Iyer
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State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
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The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
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Vulnerability exploit attempts on CVEs
Attacks on counties – USA
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In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
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LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
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- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
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Smart TV Buyer Insights Survey 2024 by 91mobiles.pdf91mobiles
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Length: 30 minutes
Session Overview
-------------------------------------------
During this webinar, we will cover the following topics while demonstrating the integrations of JMeter, InfluxDB and Grafana:
- What out-of-the-box solutions are available for real-time monitoring JMeter tests?
- What are the benefits of integrating InfluxDB and Grafana into the load testing stack?
- Which features are provided by Grafana?
- Demonstration of InfluxDB and Grafana using a practice web application
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Key Trends Shaping the Future of Infrastructure.pdfCheryl Hung
Keynote at DIGIT West Expo, Glasgow on 29 May 2024.
Cheryl Hung, ochery.com
Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
Key Trends Shaping the Future of Infrastructure.pdf
B04206015
1. Research Inventy: International Journal Of Engineering And Science
Vol.4, Issue 2 (February 2014), PP 06-15
Issn(e): 2278-4721, Issn(p):2319-6483, www.researchinventy.com
6
Monitoring of Heavy Metals in Groundwater In Makuyu
Division, Maragua District
1
B N K Njoroge, 2
Murigi I P And 3
D. Ndunge
1
Dept. of Civil and Construction Engineering, University of Nairobi, Nairobi, Kenya
2
Dept. of Civil and Construction Engineering, University of Nairobi, Nairobi, Kenya
3
Dept. of Environmental and Biosystems Engineering, University of Nairobi, Nairobi, Kenya
ABSTRACT : Analytical results have shown that the borehole and well water in Makuyu Division in Maragua
District in central Kenya is not polluted and can be consumed readily. The level of the various parameters is
low compared to recommended limits. The chemical properties monitoring showed no significant heavy metal
pollution in groundwater. The heavy metal concentrations values ranges from 0.0994 – 101450 mg/l for iron,
0.0046 – 1.0190 mg/l for manganese, 0 – 0.0588 mg/l for titanium, 0.0011 – 0.0142 mg/l for copper, 0.0027 –
0.1692 mg/l for zinc, 0.0011 – 0.0016 mg/l for strontium, 0.0012 – 0.0043 mg/l for yttrium and 0.0013 – 0.0043
mg/l for zirconium. The concentration of iron, manganese, copper, zinc, selenium, titanium, strontium, yttrium
and zirconium were determined in filtered water after pre-concentration with ammonium pyrolidine
dithiocarbonate APDC using X-ray fluorescence analysis (XRFA). The values obtained showed no significant
heavy metals pollution in groundwater. The trace metal concentrations in filtered water were below the
maximum permissible limits for drinking water as given by the World Health Organization (1993). It is only in
Kamahuha Girls High School borehole where the concentration of iron and manganese were above the WHO
standards. The XRFA technique was found to be a fast, precise, accurate and reliable method of water analysis.
Recent studies have indicated that toxicity of metals such as copper and zinc is primarily due to the presence of
the free metal iron and thus may not be directly related to the total metal concentration (Shepherd, B K et al.
1980).
I. INTRODUCTION
In the semi-arid and arid areas, groundwater is widely exploited as the major source of water. In the
other zones it is exploited to supplement existing water sources. The intensive use of natural resources and the
large production of wastes in modern society often pose a threat to groundwater quality. Degradation of
groundwater quality can take place over large areas and from various sources.Pollution can impair the use of
water and can create hazards to public health through toxicity or the spread of diseases. Most pollution
originates from the disposal of wastewater following the use of water for any of the wide variety of purposes. A
complex and interrelated series of modifications to natural water quality is created by the diversity of human
activities impinging on the hydrological cycle.
1.1 Groundwater
The main source of groundwater is precipitation, which may penetrate the soil directly to the ground or
may enter surface streams and percolate from these channels to the groundwater. Interception, depression,
storage and soil moisture must be satisfied before any large amount of water can percolate to the groundwater.
The path taken by groundwater to the zone of saturation depends on the geologic conditions. Relatively
impermeable layers above the water table may prevent direct percolation (Bouwer, 1978) Miscellaneous sources
of groundwater include water from deep in the earth, which is carried upward in intrusive rocks, and water that
is trapped in sedimentary rocks during their formation. Normally the quantities of such water are small and are
highly mineralized. The groundwater source should be as remote as possible from any source of pollution, such
as latrines, septic tanks, sewerage discharges, agricultural drainage and water discharges.Groundwater is not
stagnant, but rather moves from areas where water recharges aquifers (recharges area) to areas where it leaves
aquifers (discharge area). Groundwater moves from areas of higher elevation or higher pressure/hydraulics head
(recharge areas) to areas of lower elevation or pressure/hydraulic head. This is where the groundwater is
released into the streams, lakes, wetlands, or springs (discharge areas). Discharge areas are lakes, streams and
wetlands. The base flow of streams and rivers, which is the sustained flow between storm events, is provided by
groundwater.
2. Monitoring of Heavy Metals in Groundwater…
7
The qualification of the volume and rate of flow of groundwater in various regions is a difficult task
because volumes and flow rates are determined to a considerable extent by the geology of the region. The
characters and arrangement of rocks and soils are important factors, and these are often highly variable within a
groundwater reservoir. The direction of groundwater flow normally follows the general topography of the land
surface (Fetter, 1994).Many aquifers have been contaminated, at least locally by the improper disposal of
chemical and other wastes from solid wastes disposal sites, and from infiltrating storm water discharges.
Boundaries to groundwater flow system may be fixed geologic structure or fee water surfaces that are dependent
for their position on the state of the flow. Groundwater flow porous media may be classified as isotropic,
anisotropic, heterogeneous, homogenous or several possible combinations of these. The movement of
groundwater is governed by established hydraulic principles. Except in large caverns and fissures, groundwater
flow is almost exclusively laminar. The flow through aquifers can be expressed by what is known as Darcy’s
Law (1856). Darcy’s Law is an empirical formula that states that the velocity of flow through a porous medium
is directly propositional to the hydraulic gradient, assuming that the flow is laminar and inertia can be neglected
(Gupta, 1992).
Darcy’s Law
V=Ks
Where
V = velocity (specific discharge) (m/s)
s = slope (hydraulic gradient)
K = coefficient of permeability (hydraulic conductivity) (m/s)
And V = Q/A (m/s)
Where
Q = flow rate (volume per unit time) (m3
/s)
A = cross – section area through which flow occurs (m2
)
Thus, Q = AKs = AVactual
On the average, the actual velocity at which water is moving through an aquifer is given by
Vactual = V/P
Where P is the porosity of the aquifer
Groundwater movements thus depend on the type of aquifer and its properties (geological properties).
Groundwater Quality
Practically all types of water, i.e. runoff, groundwater and rainwater, contain some dissolved salts and
impurities. If certain elements are present in quantities above maximum allowable limits, the application of the
water to domestic use or other purpose may have adverse effects. The quality of groundwater is of great
importance in determining the suitability of a particular groundwater for a certain use, i.e. irrigation, drinking
and other domestic use, and industrial applications. Groundwater quality is influenced by the quality of its
source. The quality of groundwater is a resultant of all the processes and reactions that act on the water from the
time it is condensed in the atmosphere to the time it is discharged by a well or a spring.
1.2 Heavy Metals
Heavy metals are metallic elements including the transition series, which include many element
required for plants and animals nutrition in trace concentrations but which become toxic at higher
concentrations. Heavy metals are generally defined to include those metals of atomic weight higher than that of
sodium and having a specific gravity in excess of 5.0. The concept of toxicity is usually associated with these
terms and consequently may be applied so as to include iron, zinc, selenium, titanium, manganese, copper,
vanadium and lead. These are essential elements because they are necessary for biological functions i.e. without
them life does not exist or exists at unhealthy level. Excessive levels of trace elements occur naturally or due to
human release of metals into the environment. Once available they are not easily detoxified and thus
accumulate. Previous studies have shown that essential element such as copper, iron, selenium and manganese
exist in natural water at very low concentrations (Hume, 1975).Heavy metals exist partly in solution and partly
in suspension adsorbed to organic or inorganic particulate matter and they are generally considered to be toxic in
soluble ionic forms but toxicity is known to be reduced by water hardness (Champman and Dunlop, 1981).
3. Monitoring of Heavy Metals in Groundwater…
8
The toxicity of these metals has also been documented throughout history. Greek and Roman
physicians diagnosed symptoms of acute lead poisoning long before toxicity became a science. Exposure to
heavy metals has been linked to developmental retardation, various cancers, kidney damage and even death in
instances of very high exposure (World Resources, 1998). Excess of too much copper causes narcotic hepatitis
(Tyagi, 1992).Arsenic, barium, cadmium, chromium, mercury, nickel, selenium and thallium are toxic metals
affecting the internal organs of the human body. Arsenic is widely distributed in waters at low concentrations,
with associated instances of higher concentrations in well waters (Mari, 2004). Chromium is amphoteric and can
exist in water in several valence states. The content in natural waters is extremely low because it is held in
rocks in essentially insoluble trivalent forms. Acute systemic poisoning can result from high exposures to
hexavalent chromium. Presence of metals in potable waters is a matter of serious concern because of the toxic
nature of these materials.
II. IRON (FE) AND MANGANESE (MN)
The present of iron and manganese is common in groundwater. Iron is widespread in nature, and very
abundant occurring at concentration of about 50,000 mg/kg in the earth’s crust (Oehme, 1974). Iron occurs in
minerals like biotite, magnetite, pyroxenes, ferric oxides and hydroxides. In groundwater, the common form of
iron is the soluble ferrous ion (Fe2+
). When exposed to atmosphere it is oxidized to the ferric state (Fe3+
) which
is insoluble and causes brown discolorations of water and introduces a bitter sweet astringent taste and stains to
laundered clothes.For most purposes, the iron concentrations should not exceed 0.5 mg/l. The presence of even
this amount can be a nuisance in some industrial applications such as textile processing plants.
Iron exists in the soils as insoluble ferric oxide, iron sulfide (pyrite) and ferrous carbonate (siderite). The carbon
dioxide in groundwater reacts with ferrous carbonate, thus dissolving it as shown;
3
2
223
2 HCOFeOHCOFeCO
(aq) (g) (l) (aq) (aq)
In groundwater, ferric iron is reduced to ferrous iron and manganese dioxide is reduced to an oxidation state of
II under reducing (anaerobic) conditions. Both oxides are soluble.
On the other hand, manganese is a relatively common metal in the earth’s crust, being 12 in abundance.
It was first isolated in 1774 (WHO, 1981). Manganese is contained in minerals like biotite and hornblende. The
divalent ion Mn2+
is insoluble. When oxidized it forms black stains in laundered textiles and its concentrations
in public waters is set at 0.05 mg/l (NAS/NRC, 1973). If iron and manganese are not removed during water
treatment they can stains domestic fittings and cause brown deposits on vegetables during washing and cooking.
Their presence also in industrial processes like paper making and photographic film manufacture is a nuisance.
They cause unacceptable astringent metallic taste in water.Iron in concentration greater than 0.3 mg/l and
manganese 0.05 mg/l stains plumbing fixtures and laundered clothes. Although discoloration from precipitates is
the most serious problem associated with water supplies having excessive iron and manganese, foul tastes and
odour can be produced by growth or iron bacteria in water distribution mains. These filamentous bacteria reduce
iron as an energy source; precipitate it causing pipe encrustation (Blain, 1994).Decay of the accumulated
bacteria slimes creates offensive taste and odours. The presence of iron in water is considered objectionable
because it imparts a brownish colour to laundered goods and affects the taste of beverages, such as tea and
coffee. Dissolved iron and manganese are often found in groundwater from well located in shale sandstone and
alluvial deposits.Iron bacteria capable of using dissolved compounds containing iron include crenothix,
leptothrix, pirophyllum, gallionella and others.
The organism utilizes iron and deposit ferric hydroxide. Iron bacteria oxidize ferrous iron to ferric
iron and precipitates ferric hydrate. Some sulphur bacteria increase acidity and this tends to dissolve iron.
Under specific conditions insoluble iron sulphate may be produced. Sulphate reducing bacteria may cause the
precipitation of the iron by the production of sulphate from the reduction of sulphate. These bacteria also affect
the aerobic corrosion of iron.Generally, the presence of iron is common in groundwater. Iron is vital in the
formation of hemoglobin in human being. The essential element iron, is a component of some enzymes notably;
cytochrome and xanthine oxidase. Dietary intake of iron in excessive amount may lead to haemosiderosis or
haemochromatosis. Heamosiderosis is a condition best characterized by generalized increased iron content in
the body tissue, especially in the liver and reticuloendothenal system. Excessive dietary intake is reported to be
the cause of abnormal iron accumulation in a condition described as “Bantu Siderosis” occurring in South
Africa.
4. Monitoring of Heavy Metals in Groundwater…
9
This disease is marked by iron accumulations in the Kupffer cells of the liver and in the reticuloendothenal cells
of the spleen and bone marrow. Another unusual disorder “Kaschin – Beck disease” has been reported in Asia
excessive iron content as opposed to maximum permissible limit of 0.3 mg/l Fe/l and resulted in an arthritic
disease (US Public Health Service, 1970).
Copper (Cu)
It is widely distributed in the environment and is essential to human life, but potentially toxic at
elevated levels of exposure. Copper is very essential to human. Copper acts as a catalyst in the formation of
hemoglobin and is also involved in haemopoisis, maintenance of vascular and skeletal integrity, structure and
function of central nervous system (Norconsult, 1975). As an indicator of corrosivity, has a no action level of
1.3 mg/l in first flush sample.The symptoms of severe copper poisoning in the human body are extensive
homolysis, hepatic necrosis, nephropathy and coma, and if not treated may lead to death. Wilson’s disease is
well known. It is characterized by inability to digest copper in the body resulting in degenerative changes in the
brain and cirrhosis of the liver. The disease appears to be related to a hereditary deficiency of ceruloplasm (the
blue copper containing oxidase present in the x2 – globulin fraction of the human serum. Its major function is to
oxidize iron to the ferric state for transport by transferring. Copper deficiency therefore causes anemia. The
metal is readily adsorbed onto the particulate material, very little being present as free Cu2+
ion except stability
constants of these complexes, a tendency which dominates the chemistry of copper in water are well known.
Most copper complexes are labile and equilibria are readily established. The main pollution sources of copper
are power plants, municipal wastewater discharge, industrial processes and agriculture.
Selenium
Selenium is a trace metal naturally occurring in soils derived from some sedimentary rocks. Selenium
has a toxic effect on man and animals comparable with that of arsenic giving rise to similar symptoms.
Selenium also has been suspected of causing dental carries in man and of being a carcinogenic agent. The
selenium concentration of most drinking water is less than 0.01 mg/l. Concentrations exceeding 0.5 mg/l are
rare and limited to seepage from seleniferous soils.
Strontium (Sr)
Strontium chemically resembles calcium and cause a positive error in gravimetric and titrimetric
methods for the determination of calcium. Because strontium has a tendency to accumulate in radioactive
strontium 90, with a half – life of 28 days presents a well recognized peril to health. The natural occurring
strontium is not radioactive. For this reason, the determination of strontium in a water supply should be
supplemented by a radiological measurement to exclude the possibility that the strontium content may originate
from radioactive contamination.
Zinc (Zn)
Zinc is non cumulative, and the amount absorbed is thought to be inversely to the amount ingested.
Zinc was first demonstrated to be essential element for mammals over 45 years ago. Zinc is an essential and
beneficial element in body growth. The clinical symptoms of zinc deficiency are anorexia, pica, impaired taste
acuity, menstrual lethargy and disturbances, viz; rough, dry skin, impaired wound healing and increased
susceptibility to infection, chronic deficiency in pediatric and adolescent age group causes growth retardation
and delay of sexual maturation (Casey, 1980). Acute zinc toxicity results in haemodialysis, characterized by
nausea, vomiting, fever and severe anemia. However, concentrations above 5 mg/l can cause a stringent taste
and opalescence in alkaline waters (Dunlop, 1981). Zinc is also an essential trace element in living organisms,
being involved in nucleic acid synthesis and occurring in many other metalloenzymes. These include
dehydrogenase in photosynthesis, superoxide dismutase and carboxypeptidase. The metal occurs in water as free
cation (Zn2+
) or as soluble. Zinc complexes can be adsorbed on suspended matter. Toxicity is increased by a
decrease in dissolved oxygen content and decreased by an increase in salinity (Lloyd, 1960).
Titanium (Ti)
Titanium occurs rather abundantly in the earth’s crust and is used in large variety of industrial
processes (Mason, 1966). Titanium mainly interferes with two types of enzymes action. It inhibits borne
growth and interferes with the carbohydrate metabolism (Bruanwald et al, 1987).
III. EXPERIMENTAL METHODS
2.1 Introduction
Water samples for tests were obtained from the various boreholes and wells within the study area.
Sample bottles were cleaned carefully before each use and sterilized. Sterilization procedure for sample bottles
5. Monitoring of Heavy Metals in Groundwater…
10
was done using standard methods (WHO Geneva, 1985). Once the samples arrived at the laboratory pH was
taken using a pH meter and a buffer solution pH meter calibration. The volume of water collected was large
enough to permit an accurate analysis. The test for heavy metal was done using X-ray fluorescence
spectrometry. The parameters that were tested include iron, manganese, titanium, copper, zinc, strontium,
yttrium and zirconium.
2.2 X-Ray Fluorescence Spectrometry (XRFS)
X-ray fluorescence spectrometry is an emission spectroscopic technique that has found wide
application in many fields, which require elemental identification and determination radiation, usually in 1 – 60
Kev range following excitation of atomic electron energy levels by an external energy source such as charged
particle or x-ray beam.X-ray fluorescence analysis takes first place among instrumental techniques. This is
partially due to the coverage by the technique of more than 80 elements, to the multi-element analysis capability
for each sample and to the extremely wide range of sample form and size that can be accommodated
(MacDonald, 1980). The analytical range is broad since an element can be determined from part per million
levels up to percentages. Precision is generally good and affected little by concentration. It is non-destructive
method of analysis allowing recovery of the intact sampler after spectrometry.The advent of solid state (semi
conductor) detectors, especially those using lithium compensated silicon and low noise electronic, detection of
light elements became practical. The energy dispersive x-ray fluorescent analysis (EDXRFA) has evolved
recently with the introduction of semiconductor detectors which enable simultaneous recording of the entire
fluorescence spectrum, using radioisotope excitation sources.The energy dispersion x-ray fluorescence
(EDXRF) technique is a non-destructive instrumental method of qualitative and quantitative analysis for
chemical elements based on measurements of the wavelength and intensities of their x-ray spectral lines emitted
by secondary excitation (Bertin, 1980). The primary beam from x-ray tube or a radioisotope source irradiates
the specimen (sample or standard), exciting each element to emit secondary spectral lines having wavelengths
characteristics of that element. The detector receives excited lines of all the specimen elements at once and
generates a pulse of electric current proportional to its photon energy.
The instrument has three basic parts: - the primary source unit, the spectrometer and the measuring electronics
(Jenkins, 1982). The actual parts are:
Radioisotope source (109
Cd, 55
Fe or 241
Am) to act as the primary beam source. The 109
Cd excitation source
was used in this work. Its activity was 0.218 mci. The measurement time for each filter with 109
Cd
excitation source was 2000 seconds.
The sample compartment. It holds the sample in a precisely defined geometry during analysis and provides
for introduction and removal of the specimen during the excitation.
Lithium – drifted silicon or germanium detector (Si.Li or Ge/Li). The Si.Li detector (Canberra SI – 30180)
was used with spectral resolution of 180 ev at Mn K alpha line and associated electronics for signal
processing.
A preamplifier and an amplifier
The multichannel analyser (MCA) and if desired a micro-computer.
The spectrum evaluation software was Axil IAEA QXAS whose background model was linear order 8.
Figure 1 shows a diagrammatic representation of an EDPXRF spectrometer.
6. Monitoring of Heavy Metals in Groundwater…
11
Figure 1: Diagrammatic representation of an EDPXRF spectrometer
2.3 Sample and Sample Preservation
The water samples were collected using well-rinsed plastic containers, which had been previously
washed with hot soapy water and rinsed in de-ionized water. A minimum of four water samples at each borehole
or well was collected within a month. The pH and temperature of the water samples were recorded at each site.
The water samples were then filtered using Whiteman No. 2 filter membrane to remove suspended particles.
The water samples were preconcentrated using ammonium pyrolidine dithiocarbonate (APDC) and filtered
through a 0.45µm Millipore filter. Standards were prepared from an analytical grade of its salt. The water used
in all the work was de-ionized and doubly distilled.
2.4 Analytical Procedures for X-Ray Fluorescence
Direct XRF analysis of aqueous sample is only feasible for part per million concentration of high
atomic number element (Florkowski et al, 1976). The detention limits are approximately 5 to 10 part per
million for such elements as copper, zinc, and lead. This rather poor detection limit is due to the backscatter
background and x-ray adsorption effect. To reach detection limit in part per million ranges a preliminary
chemical enrichment must be undertaken. In this case, heavy metals were isolated by pre-concentration of the
solution using ammonium pyrolidine dithiocarbonate (APDC). Then, a 500ml of the water sample was acidified
to pH 3.8 using ammonium hydroxide analar or nitric acid analar and 10 ml of APDC added to it. The mixture
was thoroughly shaken then filtered through a 0.45um Millipore filter. The deposit on filter paper is then
analyzed using XRF. The standard solution was made from pure analytical grade salts of the elements to be
tested. Adsorption correction was done on one sample using a multi-element standard and it showed that it was
a thin film of sample deposited on the filter hence had negligible adsorption.The XRFA system used consist of
10 mci cadmium 109 radioisotope source, a liquid nitrogen cooled ORTEC, Si/Li semi-detector with a 25
micron beryllium window, an S40 Canberra multichannel analyzer (MCA) and a Dec Pro-350 micro-computer.
The source was excited using a 109
Cd radioisotope source. The emitted fluorescence radiation was then detected
using a Si/Li semiconductor detector. The signals were then amplified, shaped and sorted out by the electronic
system as per their energies by a system consisting of a pre-amplified, amplifier and a multichannel analyzer
(MCA). The intensities of the various photopeaks were determined using a quantitative x-ray analysis program
(QXAS) and the corresponding concentrations calculated with the help of a pro-350 micro-computer.
2.5 Qualitative Analysis of Environmental Samples (QAES) Program for Quantitative Analysis
The qualitative analysis of environmental samples (QAES), modular program of the International Atomic
Energy Agency (IAEA)’s Quantitative x-ray Analysis Software (QXAS) was first calibrated for quantitative
analysis by way of three sub-routines of the program available for:-
(a) Quantitative analysis of unknown samples
(b) Performing calibration of the x-ray system
(c) Calculating energy distribution of primary x-rays
7. Monitoring of Heavy Metals in Groundwater…
12
Sensitivity calibration involves determining the distribution of primary x-ray source from sub-routine and
intensity measurements of pure metal samples or analar compounds whose characteristics energies cover the
analytical range of interest. Intensities for elements for compounds together with their real densities were put to
enable the program evaluate the sensitivities and the geometrical constants. The standard used for the
calibration was pure metal foil of zinc, zirconium, iron, copper, titanium, manganese, strontium and yttrium.
For each element the experimentally determined geometrical constants for the measurement elements were
compared with the theoretically determined value. The selected values of geometrical constants of the accepted
elements were used to evaluate the average geometrical factor.
2.6 Spectral Data Analysis
A Canberra S-100 PC based multi-channel analyzer (MCA) was used for spectral data acquisition and
storage. Both the course and fine loaded filters were irradiated for 2000 seconds using 109
Cd source so as to
give reasonable statistics. The loaded filters were placed on the sample holder such as that the loaded side faced
the source of radiation as per the recommended method (IAEA, 1996). Spectrum data analysis was done using
the IAEA software. Analysis of x-ray by interactive least square fitting (AXIL). Quantitative analysis was done
using quantitative analysis of environmental samples (QAES) software (Kump, 1993). This relates the spectral
intensities with the elemental concentrations based on the fundamental parameter technique (Kinyua, 1982 and
Sparks, 1975).
2.7 Standard Solutions for Calibration
Standard solutions for calibration of the spectrometer were prepared before analysis. Standard
solutions were prepared for zinc, zirconium, iron, copper, titanium, manganese, strontium and yttrium. The
concentration range of the standards was as per the specification of the spectrometer that is 1 – 6 part per million
(Shimadzu corporation, 1991). The standards were then utilized for plotting the calibration curve for the various
elements to be analysed.
IV. RESULTS AND DISCUSSIONS
Figures 2 – 5 show the summary of the chemical properties of water samples from the 12 boreholes, 9
wells and 3 rivers in the study area. The data in the figures are mean of five month observations and also shown
are standard deviations.
RESULTS FOR VARIOUS WATER SOURCES
Figure 2; Heavy metals’ concentration (mg/l) for various water sources
8. Monitoring of Heavy Metals in Groundwater…
13
Figure 3; Heavy metals’ concentration (mg/l) for various water sources
Figure 4; Heavy metals’ concentration (mg/l) for various water sources
9. Monitoring of Heavy Metals in Groundwater…
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Figure 5; Heavy metals’ concentration (mg/l) for various water sources
V. DISCUSSION
The water samples for various sources were analyzed and results tabulated. The precision of
measurements was obtained by carrying out several tests on each source. The work was carried out in five
months (Between July and December 2002). Four samples were tested and average obtained for each month.
The water samples were obtained during the morning hours and afternoon hours. The low precision value
obtained implies that the difference between one value and another for the same element is very small. This
suggests high degree of reproducibility and hence high reliability of the methods.Precision measurements were
made for water samples. In XRFA errors can arise from high background levels and incoherent (Compton)
scattering of fluorescent intensities, which may interfere with the intensity of the measurement temperature
changes, geometry employed and matrix effects (i.e critical thickness and enhancement effects).Iron is most
abundant of these metals and potentially may have influenced the occurrence of many others such as zinc,
copper, nickel, chromium and silver. The actual concentration values do not reveal the toxic effects of some of
these heavy metals, which depend on the metal-metal interaction. It is necessary to know how these heavy
metals interact with some elements.Heavy concentrations of dissolved iron and manganese in the groundwater
can give it an unpleasant taste, and give a brownish color to food and clothes. In rural areas these chemicals can
be a serious nuisance, and may even prevent people from using the water. If so, they can often be removed by
aeration, for instance when the water falls into a storage tank from inlet. Aeration causes the iron and
manganese to become insoluble so that they form fine dark sediment, which is more easily removed.
Conclusion
From the present study findings of the status of both surface water and ground water from the 12 boreholes, nine
wells and three rivers, the following conclusions were made;-
The heavy metals pollution for the groundwater were below the world Health Organization (WHO, 1993)
and Kenya Bureau of Standards specifications for drinking water (1985).
X-ray fluorescence analysis has capability to perform multi-element analysis, the time consumed in the
analysis is minimum, also sample preparation is minimum hence contamination risks are minimum. In
conclusion, XRFA is a very useful tool for water pollution monitoring if concentrations of trace elements
area at a few part per billion levels.
Recommendations
Based on the findings of the status of the surface water and groundwater in Makuyu Division of Maragua
District, the following recommendations were made:-
The present quality of groundwater in the area is fairly good but measures should be instituted to conserve
the quality. These measures may include proper septic system design and maintenance, well/borehole head
protection and incorporation of onsite treatment systems
The community should be sensitized on the status of groundwater and be encouraged to use the
groundwater for domestic purposes
10. Monitoring of Heavy Metals in Groundwater…
15
To prevent groundwater pollution in communal water groundwater sources, awareness should be created on
hygienic matters. Clean water alone will not significantly alter health status if not accompanied by an
intensive educational programme.
The study had found groundwater source for Makuyu Division as unpolluted source in comparison with
surface water source from the three rivers. Nonetheless, there is need to ascertain the well yields especially
during the dry season, in order to ascertain the reliability of the source.
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