Research Articles

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2D-Euler Deconvolution and Forward Modeling of Gravity Data of Homa-Hills Geothermal Prospect, Kenya
(2014) Odek, A.; Otieno, A. B.; Githiri, Jg
In order to fully assess the potential of Homa Hills Geothermal prospect, the heat source which is one of the main features of a geothermal system had to be located based on its perturbation on the gravity field. Ground gravity survey was conducted in an area covering about 76 km2 and the data processed to remove all other effects which are not of geological interest. Qualitative interpretation was attempted and cross sections drawn across the anomalous areas on the complete Bouguer anomaly map. Quantitative interpretation attempted involved both Euler Deconvolution and 2‐D Forward modelling. The parameters obtained from Euler Deconvolution were used as the start up parameters for 2‐D Forward modeling. Well clustered Euler solutions were obtained at a shallow depth of approximately 200‐750 m which is consistent with the modeled shallow dike like intrusive probably of carbonatite origin.
2D-Euler Deconvolution and Forward Modeling of Gravity Data of Homa-Hills Geothermal Prospect, Kenya
(2013) Odek, O. 1; Otieno, A.B. 1; Ambusso, W.J. 1; Githiri, J. G 2
In order to fully assess the potential of Homa Hills Geothermal prospect, the heat source which is one of the main features of a geothermal system had to be located based on its perturbation on the gravity field. Ground gravity survey was conducted in an area covering about 76 km2 and the data processed to remove all other effects which are not of geological interest. Qualitative interpretation was attempted and cross sections drawn across the anomalous areas on the complete Bougu er anomaly map. Quantitative interpretation attempted involved both Euler Deconvolution and 2 ‐D Forward modelling. The parameters obtained from Euler Deconvolution were used as the start up parameters for 2 ‐D Forward modeling. Well clustered Euler solutions were obtained at a shallow depth of approximately 200‐750 m which is consistent with the modeled shallow dike like intrusive probably of carbonatite origin
A Backward Regressed Capsule Neural Network for Plant Leaf Disease Classification
(Heliyon, 2021) Mugo, D. M.; Kenduiywo, B. K.; Too, E. C.
This study investigated the introduction of backward regression coupled with DenseNet features into a Capsule Neural Network (CapsNet) for plant leaf disease classification. Plant diseases are considered one of the main factors influencing food production, and therefore fast crop diseases detection and recognition is important in enhancing interventions. In the recent past, CapsNets have been used for plant leaf disease classification with some success. However, back propagation of signals to earlier layers is still a challenge due to low gradient flow, parameter and computational complexities exist due to lack of feature diversification which leads to poor patterns, and uses only higher level features while all features are necessary for classification. This work therefore adopted DenseNet intuition where a loop connectivity pattern was done in the convolution layer, a technique that made it easier for signals to be back propagated and create a strong gradient flow. The resultant model was able to attain computational and parameter efficiency because feature diversification led to richer patterns hence higher accuracy. The resultant model maintained low complexity as it used both complex and simple features. After feature collected in the convolution layer, backward regression was introduced to select only the features that had significant information to be used by the model, a technique that reduced computation time and reduced characters in the model without the loss of data. This work used the standard PlantVillage (PV) dataset comprising of ten tomato classes with a total of 9080 images and observed 99% accuracy on testing with backward regression and 87% on testing without backward regression.
A Backward Regressed Capsule Neural Network for Plant Leaf Disease Detection
(Science Publications, 2022) Jepkoech, J.; Kenduiywo, B. K.; Mugo, D. M.; Too, E. C.
This study investigated the introduction of backward regression coupled with DenseNet features in a Capsule Neural Network (CapsNet) for plant leaf disease classification. Plant diseases are considered one of the main factors influencing food production and therefore fast crop disease detection and recognition are important in enhancing food security interventions. CapsNets have successfully been adopted for plant leaf disease classification however, backpropagation of signals to preceding layers is still a challenge due to low gradient flow. In addition, parameter and computational complexities exist due to complex features. Therefore, this study implemented a loop connectivity pattern to improve gradient flow in the convolution layer and backward regression for feature selection. We observed a 99.7% F1 score with backward regression and 87% F1 score without backward regression accuracy on testing our framework based on the standard Plant Village (PV) dataset comprising ten tomato classes with 9080 images. Additionally, CapsNet with backward regression showed relatively higher and stable accuracy when sensitivity analysis was performed by varying testing and training dataset percentages. In comparison Support Vector Machines (SVM), Artificial Neural Networks (ANN), AlexNet, ResNet, VGGNet, Inception V3, and VGG 16 deep learning approaches scored 84.5, 88.6, 99.3, 97.87, 99.14, and 98.2%, respectively. These findings indicate that the introduction of backward regression of features in the CapsNet model may be a decent and, in most cases superior and less expensive alternative for phrase categorization models based on CNNs and RNNs. Therefore, the accuracy of plant disease detection may be enhanced even further with the aid of the fusion of several classifiers and the integration of a backward regressed capsule neural network.
A Comparative Study of Caffeine Levels in Coffee and Cocoa in Kenyan Supermarkets and Shops
(Pan-African Journal of Health and Environmental Science, 2024-05-20) Alex Muthengi1*, Silas Njiru1 and Juster Mungiria; ; ;
Background: Caffeine is an alkaloid belonging to the methylxanthine family. An overdose of caffeine causes the following side effects: restlessness, nervousness, excitement, insomnia, flushed face, diuresis, gastrointestinal disturbances, muscle twitching, rambling flow of thought and speech, and tachycardia or cardiac arrhythmia. This study aimed to determine the caffeine levels of various brands of coffee and cocoa and enlighten people on the safe and healthy consumption of the two products. Methods: Different brands of coffee and cocoa products were randomly sampled and purchased from supermarkets and shops in Nairobi, Kenya. Five samples of coffee and four brands of cocoa were purchased from a supermarket and taken to the laboratory for analysis. Caffeine was extracted, and quantitative analysis was done using High Performance Liquid Chromatography (HPLC). Results: The study found that coffee has a higher concentration of caffeine than cocoa. Coffee Brand A recorded the lowest level of caffeine with 30.9845 µ g/g, while Coffee Brand C recorded the highest level of caffeine with 426.9639 µ g/g. Among the Cocoa brands, Cocoa Brand B recorded the lowest level of caffeine (2.6367 µg/g), while Cocoa Brand C recorded the highest level of caffeine at 19.03 µ g/g. Conclusion: Therefore, there is a need to reduce coffee consumption per day because caffeine overdose can cause high blood pressure and other illnesses. Cocoa is recommended for consumption since it contains less caffeine per servin
A History of the Presbyterian Church of East Africa in The Eastern Region (1915 To 2022)
(Journal of History and Cultural Studies, 2024-02-10) Lucy Muthoni Mwindi(1) ; Dickson Nkonge Kagema(2) ; Caroline Mucece Kithinji(3
The study sought to trace the history of the Presbyterian Church of East Africa (PCEA) in the Eastern Region from 1915 to 2022. PCEA was introduced by the Church of Scotland Mission (CSM) in 1915. It has been in the Eastern Region (Tharaka Nithi and Meru counties) for over a century now and is one of the dominant denominations in the area. However, no systematic study has been done to trace its history. The history of the Methodist Church in Kenya, the Anglican Church, and the Catholic Church in the Eastern Region is well documented, but that of PCEA in the region is conspicuously missing. This gave the authors the impetus to carry out such a study. The study adopted a descriptive survey research design. Data was collected and analysed from 438 respondents, including 9 presbytery moderators, 53 church ministers, and 376 church members. The study established that PCEA was brought to the Eastern Region by the CSM. The first missionaries were Africans sent from Kikuyu and Tumutumu. They were later joined by Dr Clive Irvine in 1922. A mission station was established at Chogoria, from where the church spread to other parts of the lower and upper Meru. The study concludes that PCEA is one of the dominant denominations in the Eastern Region. The study recommends that PCEA should come up with better methods of storing data to avoid losing it and preserve its heritage
A Machine Learning-Based Prediction of Malaria Occurrence in Kenya
(American Journal of Theoretical and Applied Statistics, 2024-08-20) Dennis Muriithi* , Victor Wandera Lumumba , Mark Okongo
For many years’ malaria has been a health public concern in Kenya as well as many parts of Africa and other parts of the world. The purpose of this study is to develop and evaluate a supervised machine learning model to predict malaria occurrence (final malaria test results) in Kenya. The study investigated twelve predictor variables on the outcome variable (malaria test results), where five machine learning models namely; k-nearest neighbors, support vector machines, random forest, tree bagging, and boosting, were estimated. During the model evaluation, random forest emerged as the best overall model in the classification and prediction of final malaria test results. The model attained a higher classification accuracy of 97.33%, sensitivity of 71.1%, specificity of 98.4%, balanced accuracy of 84.7% and an area under the curve of 98.3%. From the final model, the presence of plasmodium falciparum emerged most important feature, followed by region, endemic zone and anemic level. The feature with the least importance in predicting final malaria test results was having mosquito nets. In conclusion, employing Machine learning algorithms enhances early detection, optimizing resource allocation for interventions, and ultimately reducing the incidence and impact of malaria in the Kenya. The study recommends allocation of resources and funds to areas with the presence of plasmodium falciparum, region susceptible to malaria, endemic zones and anemic prone areas.
A Machine Learning-Based Prediction of Malaria Occurrence in Kenya
(American Journal of Theoretical and Applied Statistics, 2024-08-20) Dennis Muriithi* , Victor Wandera Lumumba , Mark Okongo
The purpose of this study is to develop and evaluate a supervised machine learning model to predict malaria occurrence (final malaria test results) in Kenya. The study investigated twelve predictor variables on the outcome variable (malaria test results), where five machine learning models namely; k-nearest neighbors, support vector machines, random forest, tree bagging, and boosting, were estimated. During the model evaluation, random forest emerged as the best overall model in the classification and prediction of final malaria test results. The model attained a higher classification accuracy of 97.33%, sensitivity of 71.1%, specificity of 98.4%, balanced accuracy of 84.7% and an area under the curve of 98.3%. From the final model, the presence of plasmodium falciparum emerged most important feature, followed by region, endemic zone and anemic level. The feature with theleast importance in predicting final malaria test results was having mosquito nets. In conclusion, employing Machine learning algorithms enhances early detection, optimizing resource allocation for interventions, and ultimately reducing the incidence and impact of malaria in the Kenya. The study recommends allocation of resources and funds to areas with the presence of plasmodium falciparum, region susceptible to malaria, endemic zones and anemic prone areas.
A Short History of the Anglican Church in Meru, Kenya (1969- 2009)
(IISTE, 2016) Kagema, Dickson Nkonge
This paper traces the history of the Anglican Church (AC) in Meru since its inception in 1969 to 2009, forty years of evangelization. Although the AC is the oldest Christian denomination in Kenya having been started in 1844 by the Church Missionary Society (CMS(Anglican)), where it was able to reach to most parts of Kenya, it took a long time (125 years) to reach Meru region(What is today Meru and Tharaka Nithi Counties). During the subdivision of Kenya into ‘missionary spheres of influence’ this region had been given to CMS but for various reasons the CMS failed to occupy it prompting the Church of Scotland Mission (CSM) (Presbyterian), Consolata Catholic Mission (CCM)((Roman Catholic), United Free Methodist Churches (UFMC) and others to desire to evangelize there. Thus by the time the AC was introduced in Meru from Embu after independence, other denominations including the Catholic Church, Methodist Church, Presbyterian Church and Pentecostals were already thriving in Meru where they had many followers. The AC began in Southern Meru in 1969 and within a short time it was able to spread to almost all parts of Meru region. This paper looks at its history and development for the first forty years. In these years, this Church experienced a tremendous numerical growth but not without challenges which have sometimes been very detrimental to evangelization. The paper concludes that the AC has a promising future in Meru if priorities are set right especially in the area of leadership and pastoral care.
A Syntactic Analysis of Raising Structures in Kĩmũthambĩ
(Chuka University, 2022) Kaburo, Diana Kananu
This paper provides a syntactic analysis of noun phrase movement in raising predicates in Kĩmũthambĩ, a Bantu language, spoken in Kenya. Kĩmũthambĩ belongs to the larger Kikuyu-Kamba group (E50) and is classified as E531 Mwimbi-Muthambi by Eberhand et al. (2022). The study is guided by the Minimalist Program developed by Chomsky (1995). This theory recognizes that there is always a trigger movement which is the need to check features at an appropriate landing site. The paper demonstrates that Raising in Kĩmũthambĩ is triggered by need to check case features. Since raising verbs cannot assign case to a NP, the NP must move to a position in a sentence where it can be assigned case. This according to Carnie (2007) is due to the fact that the NP and the case assigner must be local in such a way that it must be the specifier or the complement of the case assigner, in order to check the feature of case. Case therefore becomes a mandatory trigger for movement of NPs that are not in positions that can be assigned case as in the case of raising predicates. The paper also demonstrates that unlike in English where raising occurs on non-finite clauses only, Kĩmũthambĩ allows raising of subjects out finite clauses a situation referred to as hyper-raising. This study contributes to the study of Kĩmũthambĩ, a language that has had little research attention. It also contributes to the body of knowledge on raising structures in Bantu languages.
Ab initio Investigation of the Structural and Electronic Properties of Alkaline Earth Metal - TiO2 Natural Polymorphs
(Hindawi Advances in Materials Science and Engineering, 2022) Mbae, J.K.; Muthui, Z.W.
Titanium (IV) oxide (TiO2) has gained much attention due to its application in technologies such as optoelectronics, electronics, sensors, photocatalysts, and sustainable energy generation. However, its optical absorption falls in the ultraviolet part of the electromagnetic spectrum, resulting in a low absorption ratio of solar light. In addition, rapid electron-hole recombination limits its photocatalytic activity. To extend the application range of TiO2, the structural and chemical properties can be modified by adding various dopants to tune its electronic structure for applications within a wider range of the solar energy spectrum and ideally extend towards the visible region, which forms the dominant part of the solar energy spectrum. In this study, the structural and electronic properties of three polymorphs of TiO2 have been studied using density functional theory (DFT) as implemented in the Quantum ESPRESSO simulation package. )e exchange-correlation potential has been treated with the generalised gradient approximation (GGA). Cationic substitution with non-toxic alkaline earth metal dopants Mg and Ca has been carried out with the aim of modifying the electronic structure of the polymorphs of TiO2. On 1–4% Mg and Ca cationic substitution, there is a slight expansion of the optimal unit cell volume and modulation of the band gap energy by raising the valence band maximum to higher energies. In addition, dopant inter and intra-band states are observed.
Abagusii traditional environmental knowledge and HIV/AIDS management: Implications for English language teaching
(International Ecolinguistics Association, 2021-05) Maroko, G.M.; Mokua, G.N.; Nyakundi, A.O.; Onyambu, M.O.
Multidisciplinary and multisectoral interventions are necessary for the management of chronic conditions such as HIV/AIDS. One such intervention is the promotion of socially responsible teaching. Anchored within an eclectic theoretical framework involving traditional environmental knowledge, the Sapir-Whorf Hypothesis, and Vygotsky’s theory of thought, language and culture, this paper analyses the link between Abagusii traditional environmental knowledge and management of HIV/AIDS. Seven groups of people living with HIV/AIDS were engaged in focus group discussions on the management of HIV/AIDS treatment adherence through sustainable production and use of natural products. The paper reveals that the Abagusii have rich ecological knowledge on the production and use of natural products, which could improve treatment outcomes of people living with HIV/AIDS. This ecological knowledge can be harnessed, documented and ploughed into ELT materials for English Language Teaching. A three-tier ELT framework comprising classroom activities, integrated tasks and practical actions could be adopted for teaching integrated English in interesting ways while at the same time restoring the environment, food sufficiency and health.
Abagusii Traditional Environmental Knowledge and HIV/AIDS Management: Implications for English Language Teaching
(International Ecolinguistics Association, 2021) Maroko, G. M.; Mokua, G. N.; Nyakundi, A. O.; Onyambu, M. O.
Multidisciplinary and multisectoral interventions are necessary for the management of chronic conditions such as HIV/AIDS. One such intervention is the promotion of socially responsible teaching. Anchored within an eclectic theoretical framework involving traditional environmental knowledge, the Sapir-Whorf Hypothesis, and Vygotsky’s theory of thought, language and culture, this paper analyses the link between Abagusii traditional environmental knowledge and management of HIV/AIDS. Seven groups of people living with HIV/AIDS were engaged in focus group discussions on the management of HIV/AIDS treatment adherence through sustainable production and use of natural products. The paper reveals that the Abagusii have rich ecological knowledge on the production and use of natural products, which could improve treatment outcomes of people living with HIV/AIDS. This ecological knowledge can be harnessed, documented and ploughed into ELT materials for English Language Teaching. A three-tier ELT framework comprising classroom activities, integrated tasks and practical actions could be adopted for teaching integrated English in interesting ways while at the same time restoring the environment, food sufficiency and health.
Action and variation potential electrical signals in higher plants
(African Journal of Biological Sciences, 2021) Ndung’u, Ruth Wairimu; Kamweru, Paul Kuria; Kirwa, Abraham Tuwei
This review evaluates the types of electrical signals (ESs) in plants, generation and propagation of various ESs, their ways of transmission within the plant body and their corresponding physiological significance. It also outlines abiotic factors, e.g., light, temperature, water content as stimuli on the electrical potential (EP) of the plants. The paper also summarizes a review of the effects of ESs on photosynthesis, the mechanisms of the effects, and its physiological role in plants. Local irritations of plants induce various photosynthetic responses including fast and long-term inactivation of photosynthesis and its activation. The paper also reviews the concept of plant energy harvesting. The measurement techniques used for ESs in plants including extracellular measurement and intracellular measurement are also reviewed. A brief summary of the applications of these methods for investigating ES in plants is also given.
Addressing the prevalence of alcohol and drug abuse among the youth in the Presbyterian churches in Kenya
(Journal of humanities and social sciences, 2022-08-25) Mathai, Lucy Mutare
This article sought to assess the reasons for the prevalence of alcohol and drug abuse among the youth in the Presbyterian churches (PCEA) and to investigate the success rate of the strategies used by the PCEA in addressing alcohol and drug abuse among the youth. Three PCEA regions were selected using the multistage cluster sampling technique. A proportional sampling technique was used to get PCEA Presbytery moderators, church elders, Parish ministers and youth members. The youth who are abusing alcohol and drugs were identified through the snowball sampling technique. Purposive sampling was used to select the Youth Director. A descriptive survey research design was used to obtain qualitative data. Instruments for data collection were questionnaires, structured interview schedules and focus group discussions. Data were analyzed qualitatively and presented in summary form using frequency tables and discussions. The study established that the reasons for the prevalence of alcohol and drug abuse among the youth in the PCEA are peer influence, curiosity and easy availability of alcohol and drugs. The strategies used by PCEA in addressing alcohol and drug abuse include seminars and workshops (56%), bible studies (31%), alcoholic forums (44%), youth camps and conferences (56%), rallies and crusades (43%), guidance and counselling programmes (45%), youth engagement in community work (71%) and having a drug education desk (30%). The study recommends that the Church should reassess the strategies with the aim of making them more effective. The youth should be involved in the management of the strategies.
Addressing the Prevalence of Alcohol and Drug Abuse Among the Youth in The Presbyterian Churches in Kenya
(Editon Consortium Publishing, 2022) Mathai, L. M.
This article sought to assess the reasons for the prevalence of alcohol and drug abuse among the youth in the Presbyterian churches (PCEA) and to investigate the success rate of the strategies used by the PCEA in addressing alcohol and drug abuse among the youth. Three PCEA regions were selected using the multistage cluster sampling technique. A proportional sampling technique was used to get PCEA Presbytery moderators, church elders, Parish ministers and youth members. The youth who are abusing alcohol and drugs were identified through the snowball sampling technique. Purposive sampling was used to select the Youth Director. A descriptive survey research design was used to obtain qualitative data. Instruments for data collection were questionnaires, structured interview schedules and focus group discussions. Data were analyzed qualitatively and presented in summary form using frequency tables and discussions. The study established that the reasons for the prevalence of alcohol and drug abuse among the youth in the PCEA are peer influence, curiosity and easy availability of alcohol and drugs. The strategies used by PCEA in addressing alcohol and drug abuse include seminars and workshops (56%), bible studies (31%), alcoholic forums (44%), youth camps and conferences (56%), rallies and crusades (43%), guidance and counselling programmes (45%), youth engagement in community work (71%) and having a drug education desk (30%). The study recommends that the Church should reassess the strategies with the aim of making them more effective. The youth should be involved in the management of the strategies.
ADMINISTRATIVE FACTORS AFFECTING STUDENT LEADERSHIP IN PUBLIC SECONDARY SCHOOLS IN THARAKA SOUTH SUB COUNTY, KENYA
(International Journal of Creative Research and Studies, 2020-05) Gitonga Mubiu, Jeremy; Mugero Muchiri, Joyline
Student leadership in public secondary schools is very important. Student leaders assist the school administration to manage the school by bridging the gap between students and teachers. Effective student leadership is able to address many administrative problems by communicating the students’ needs to the relevant authorities for timely and necessary action. For a school to have effective student leadership, factors affecting these student leaders within the school framework must be addressed. There are several factors that affect students’ leadership in secondary schools. The purpose of the current study was to determine administrative factors affecting students’ leadership in public secondary schools in Tharaka South Sub County. The study employed descriptive survey research design. The target population of the study was 3850 subjects comprising of students, student leaders and deputy principals in the 25 public secondary schools. A sample of 25 deputy principals, 100 student leaders and 225 students participated in the study. A questionnaire was used to collect data from the respondents. Piloting was conducted prior to data collection in the neighboring Tharaka North Sub County. Spearman Rank Correlation Coefficient formula was used to estimate reliability of the instruments and a correlation coefficient of 0.81 was obtained. Validity of the instruments was established through experts’ judgment from the university supervisors. The data collected was analyzed using frequencies, mean and percentages with the help of Statistical Package for Social Scientists (SPSS) version 17.0. Study findings established that schools offered minimal training programs for student leaders’ development, and very little motivation programs like tours for the student leaders. Most schools provided physical facilities like offices for student leaders and gave full authority to student leaders to punish wrongdoers. The findings also revealed that most schools did not have student leaders’ election period in their calendar. The study recommended that schools should look for ways of offering training programs to student leaders to better their leadership skills and also initiate motivation programs for student leaders.
Adoption of Near Field Communication in Universities in Kenya
(2015-09) Muthengi, Fredrick Mugambi; Njebiu, Victor Mwenda
In our day to day life, the adoption of new technology to new innovation in various sectors is rising. Campus life has shifted from students’ carrying laptops and a bag full of pass cards to carrying Ipads or smart phones. Barcode bars on pass and identification cards have been replaced by near field communication (NFC) instructions. NFC is a technology standard for very-short-range wireless connectivity that enables quick, secure two-way interactions among electronic devices. The level of global interaction and mode of communication is changing and the adoption of Near Flied Communication is on the rise, replacing bar code and QR code. The technology is at advanced stages ranging from file transfer; access controls to paying for goods and services on NFC enabled payment points/devices or cards. The introduction of Near Field Communication in the universities has enhanced the speed of processes as well as simplifying them. The pass cards/ids students carry along and time spent on queues waiting to be served is reduced. This paper explores the advantages of near field communication over magnetic bar codes and QR codes in an academic institution. Near field communication combines several instructions which are read via NFC enabled devices: smart phones or tags. Student card is customized with NFC tag: from library card, access control card to student identification card. NFC is at early stages of implementation in Kenya but has been successfully rolled out in transport industry as Bebapay. With the rise of mobile enabled near field communication devices, its adoption in Kenyan universities will be a success.
Adoption of Near Field Communication in Universities in Kenya
(2015-09) Muthengi, Fredrick Mugambi; Njebiu, Victor Mwenda
In our day to day life, the adoption of new technology to new innovation in various sectors is rising. Campus life has shifted from students’ carrying laptops and a bag full of pass cards to carrying Ipads or smart phones. Barcode bars on pass and identification cards have been replaced by near field communication (NFC) instructions. NFC is a technology standard for very-short-range wireless connectivity that enables quick, secure two-way interactions among electronic devices. The level of global interaction and mode of communication is changing and the adoption of Near Flied Communication is on the rise, replacing bar code and QR code. The technology is at advanced stages ranging from file transfer; access controls to paying for goods and services on NFC enabled payment points/devices or cards. The introduction of Near Field Communication in the universities has enhanced the speed of processes as well as simplifying them. The pass cards/ids students carry along and time spent on queues waiting to be served is reduced. This paper explores the advantages of near field communication over magnetic bar codes and QR codes in an academic institution. Near field communication combines several instructions which are read via NFC enabled devices: smart phones or tags. Student card is customized with NFC tag: from library card, access control card to student identification card. NFC is at early stages of implementation in Kenya but has been successfully rolled out in transport industry as Bebapay. With the rise of mobile enabled near field communication devices, its adoption in Kenyan universities will be a success.
Adsorption of Lead (II) Ions from Aqueous Solutions Using Mangroves Roots (Rhizophora Mucronata) Charcoal-Carbon Nanotubes Nanocomposite
(Journal of Multidisciplinary Engineering Science and Technology (JMEST), 2021) Ngugi, Fidelis; Mwangi, Joel; Njagi, Eric; Ombaka, Ochieng
Providing clean and affordable water to meet human needs is a grand challenge of the 21st century. Worldwide, water supply struggles to keep up with the fast growing demand, which is exacerbated by population growth, global climate change, and water quality deterioration. Nanotechnology holds great potential in advancing water treatment to improve water treatment efficiency. In this study, Mangrove Roots Charcoal and Carbon Nanotubes (MRCCNTs) nanocomposite was synthesized and utilized as a novel adsorbent for the removal of lead ions from aqueous solutions. The efficacy of MRC-CNT nanocomposites was investigated in batch mode which involved the effects of pH, temperature, concentration of the lead ions, adsorbent mass and contact time on adsorbates removal. Characterization of the adsorbent was carried out by Scanning Electron Microscopy (SEM) to observe the morphology of the adsorbent and surface area analysis and Energy Dispersive X-ray spectroscopy (EDX) to determine the elemental composition of the adsorbent. Adsorption isotherm models and adsorption kinetic studies were used for data analysis. It was observed that the removal efficiency of Pb (II) ions depended on pH of solution and the maximum efficiency was noticed at pH 7 with adsorption capacity of 3.629 mg/g which was calculated by the Freundlich isotherm model. Kinetic studies were well suited and found in good agreement with pseudo-second order. The results indicated that MRC-CNT nanocomposites would be a promising adsorbent for adsorption of Pb (II) ions from aqueous solutions.

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