Chemical Engineering Commons^™

Using Switchable Solvents For Enhanced Biodiesel Production, Eyad Abdel Rahman Sowan

Theses

This thesis presents a sustainable approach to biodiesel production using in-situ technology for direct conversion of microalgae-to-biodiesel. The proposed method operates on wet, untreated microalgae, thereby eliminating the cost/energy intensive drying and cell disruption steps. Owing to their favorable properties, the use of enzymes, specifically lipase, as a catalyst for the process was suggested over acid/base catalysts. However, the high cost of the enzyme necessitates its reuse at sustained activity for the process to be economically feasible. The use of non-toxic green solvents, such as switchable solvents, as an alternative to conventional organic solvents was a significant challenge for the …

Dendrimer And Dendrimer Gel-Derived Drug Delivery Systems: Breaking Bottlenecks Of Topical Administration Of Glaucoma Medications, Juan Wang, Boxuan Li, Uday B. Kompella, Hu Yang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Due to high structural flexibility, multidrug carrying capability, and tunable size, dendrimers have been used as suitable carriers for ophthalmic drug delivery. Drug molecules can be either encapsulated or chemically coupled to dendrimers. the nanoscopic size, spheroidal shape, and cationic surface of Poly amidoamine (PAMAM) dendrimers promote their interaction with the cornea and result in prolonged precorneal retention. Dendrimers could be further cross-linked to produce three-dimensional hydrogel networks or dendrimer hydrogels (DH). the properties of the DH can be readily adjusted to maintain both fluidity and adhesiveness, making them suitable for developing topical ocular drug formulations. Micro-/nano- sized DHs, that …

Optimization Of Co2 Huff-N-Puff In Unconventional Reservoirs With A Focus On Pore Confinement Effects, Fluid Types, And Completion Parameters, Aaditya Khanal, Md Fahim Shahriar

Jasper Department of Chemical Engineering Faculty Publications and Presentations

The cyclic injection of CO2, referred to as the huff-n-puff (HnP) method, is an attractive option to improve oil recovery from unconventional reservoirs. This study evaluates the optimization of the CO2 HnP method and provides insight into the aspects of CO2 sequestration for unconventional reservoirs. Furthermore, this study also examines the impact of nanopore confinement, fluid composition, injection solvent, diffusivity parameters, and fracture properties on the long-term recovery factor. The results from over 500 independent simulations showed that the optimal recovery is obtained for the puff-to-huff ratio of around 2.73 with a soak period of fewer than 2.7 days. After …

Exploring Current And Future Research Trends On Safety Climate In Construction Projects, Kamugisha Joseph Kajumulo

Tanzania Journal of Engineering and Technology (TJET)

Clients, consultants, and contractors in the construction industry can benefit from a safety climate by obtaining knowledge of attitudes and perceptions for better safety outcomes. However, the current and future research trends for safety climate in construction projects have not yet been fully examined. In order to solve this problem, a systematic review of previous research findings using a social network approach must be conducted, and future trends for the safety climate in building projects must be identified. Sixty-three peer reviewed articles were gathered to study the literature on safety climate in construction projects. A social network approach was employed …

The Fourth Industrial Revolution: Opportunities And Challenges To The Future Of Mechanical Engineering, Ulingeta O.L. Mbamba

Tanzania Journal of Engineering and Technology (TJET)

This paper provides a conceptual overview of the developments of the Fourth Industrial Revolution (4IR) and derives challenges and opportunities for the future of the mechanical engineering profession. The paper broadly defines 4IR as the fusion of technologies and interaction across physical, digital and biological aspects, while defining mechanical engineering as "a multi-faceted discipline that encompasses the teaching, practice and guidance of others in the development and application of scientific principles to mechanical systems". The paper looks specifically at developments in the Internet of Things (IoT), blockchain technology, robotics, Big Data analytics, biotechnology, nanotechnology, 3D printing and artificial intelligence and …

Model For Calculating The Static Characteristics Of Hydraulic Systems Of Hydro Technical Buildings, Mirkhalil Ismailov, Dong Zhang, Farkhod Kasimov

Chemical Technology, Control and Management

Hydraulic mechanisms that actuate flat gates, widely used in hydraulic structures, are studied as hydraulic actuators of the system. Their static mathematical models are developed using an integrated methodology with a hydraulic pump, inlet and suction pipes, and internal and external resistance factors. Unlike existing mathematical models, the model developed in this paper allows a detailed description of the characteristics of hydraulic drives due to the fact that pressure losses in the throttle, regulator, and power amplifier, as well as local resistances in hydraulic pipelines, are taken into account.

Synchronization Of The Training Of Specialists In The Automation Of Technological Processes In Accordance With The Dynamics Of The Taxonomy Of Learning Goals, Yusuf Shodievich Avazov, Kamola Abdullaeva

Chemical Technology, Control and Management

Changes in the characteristics of modern ones, reflecting them as the "digital generation", inevitably necessitate electronic interactive, mobile and mixed, machine learning, especially in the field of automation and control of technological processes and production. As a consequence of reflecting these realities, there have been parallel changes in the taxonomy of learning objectives - from the classical to the revised rethought and digital.

In order to study the problem of synchronizing the training of future specialists in the field of automation and control of technological processes and production and funny knowledge in accordance with the dynamics of the taxonomy of …

Analysis Of Vegetable Oil Refining Technology, Elyor Samadov

Chemical Technology, Control and Management

Innovative technologies for refining vegetable oils are presented, as well as the qualitative characteristics of raw vegetable oils obtained by extraction and mechanical methods. A general review of the chemical composition and impurities of vegetable oils resulting from the reaction between glycerol and fatty acids is carried out, and a brief review of the study to determine the effect of refining on biologically active components.

The analytical review is devoted to a comparative comparison of two types of refining - chemical and physical refining.

Research Of Three-Phases Current’S Transducers Of Filter-Compensation Devices For Control Reactive Power’S Consumption Of Asynchronous Motor, Ilkhomjon Khakimovich Siddikov, Dilyorbek Karimjonov Doniyorbek O'G'Li -, Abdumutal Abdikarimovich Abdigapirov

Chemical Technology, Control and Management

In the article given materials of developing of three-phase electromagnetic current transducers of reactive power, using with asynchronous motor, methods connecting of two sensing element, series, parallel and differential and loops suitable for each phase, dynamic characteristics of output signals of three-phase electromagnetic current transducers asynchronous motor.

On the basis of modern calculation and design complexes are of great importance in the research variable sizes of three-phase current electromagnetic transducers of filter-compensation devices of reactive power of asynchronous motors. Presented mathematical model of research of electrical, electromagnetic and magnetic elements of electromagnetic current transducers in the …

3d Printed Composite Structures For Bone Repair And Drug Delivery Application, Innocent J. Macha

Tanzania Journal of Engineering and Technology (TJET)

Due to the increase in traffic accidents, industrial contingencies, and natural disasters, there is a high demand for bone regeneration biomaterials. Although bone can regenerate and self-repair, it is difficult to do so when the defect area exceeds the critical repair area due to trauma, tumour resection, or congenital diseases. The traditional methods for bone repair are autograft, allograft, and xenograft. However, these methods have flaws and limitations, such as complications in the donor bone area, a limited number of donors, rejection, and infectious diseases. However, in recent years, the use of additive manufacturing technologies in bone tissue engineering has …

Towards Lean Manufacturing In Developing Countries: Research Gaps And Directions In Tanzania, Francis D. Sinkamba

Tanzania Journal of Engineering and Technology (TJET)

In the current knowledge-driven economy, many industries across the globe are forced to adopt manufacturing technologies such as lean manufacturing to remain competitive in the globalized world. Despite the increase in lean manufacturing implementations, the adoption rate in Tanzania is very low and estimated to be 8 percent. Likewise, the sustainability of lean manufacturing tools and practices is still questionable, which shows the need to develop lean maturity models. To date, several lean maturity models have been developed but there is ARTICLE INFO Submitted: July 5, 2022 Revised: Sept. 28, 2022 Presented: Oct. 20, 2022 a lack of maturity models …

Factors Influencing Total Productive Maintenance Implementation For Thermal Generation Plants, Ismail W. R. Taifa Dr

Tanzania Journal of Engineering and Technology (TJET)

This study accepts that the technical and administrative factors can amplify effective total productive maintenance (TPM) implementation at thermal generation plants. It is noted that there is a limited number of studies that have attempted to understand the subject of TPM implementation in the energy sector. Noting this shortcoming, the authors thought it crucial to generate empirical evidence on the factors influencing effective TPM implementation for thermal generation plants, with evidence from gas-fired plants. A sample of 88 respondents was selected and consulted. Data were collected through questionnaires and analyzed quantitatively by inferential statistics and qualitatively through thematic analysis using …

Preparation And Characterization Of Microporous Cellulose Membranes As Potential Pathogen Filters, Peresi M. Bulemo

Tanzania Journal of Engineering and Technology (TJET)

Growth and development in the textile and fashion industry have resulted in the generation of large amounts of industrial pre consumer textile wastes. It is estimated that 10 to 20% of textile fabrics are wasted during garment manufacturing, with most of the wastes being burned or landfilled. Reusing pre-consumer fabric wastes is therefore considered a viable approach to alleviate environmental impacts associated with their disposal. To achieve a higher porosity membrane, pre-consumer cotton fabrics were partially dissolved in a solution of dimethyl acetamide (DMAc) and lithium chloride (LiCl), and the resulting fibre suspension was utilized to prepare a microporous cellulose …

Extraction And Characterization Of Collagen From Cattle Horns For Potential Wound Healing, Yeriko Halson

Tanzania Journal of Engineering and Technology (TJET)

The need for bandages and gauze for wound dressing and healing is inevitable due to the high increase in accidents. Most of the material used for the production of bandages and gauzes for wound healing are from non-renewable synthetic material. The sustainability of non renewable resources is at jeopardy due to the health and associated environmental impact. Consequently, the use of naturally occurring and biodegradable material is a promising solution to the sustainability challenges of synthetic material. In this paper, the extraction of collagen films from cattle horns for potential wound healing is reported. Collagen was extracted from cattle horns …

Current And Future Trends Of Construction Project Performance Models: A Review, Method Mtana

Tanzania Journal of Engineering and Technology (TJET)

The construction industry (CI) has experienced outstanding growth and contributed to economic growth for many countries, with enormous foreign investments that require quality projects. High pressure to reduce the construction cost and time commonly put the industry at risk of lower quality and safety of the construction facilities. Like many other developing countries, Tanzania needs more stringent quality control measures in the construction sector to contribute positively to sustainable growth. This study thus reviews current and future trends in construction industry performance in Tanzania. The literature review on construction projects (CPs) performance is based on information on time overruns from …

Towards The Development Of A Framework For Assessing Organizational Governance Maturity For Technical Audit Of Public Works, George Haule

Tanzania Journal of Engineering and Technology (TJET)

The quality of the audit work and its products is often associated with the organizational maturity of the audit function. The absence of a well-defined organizational maturity for an audit function leads to poor quality of audit work or products and ineffective audit function. The lack of a framework for measuring governance maturity was identified as a major deterrent factor to the attainment of quality audit work. Measuring the governance maturity of the technical audit of public works is challenging due to the absence of a maturity framework that fits its needs. The noted shortcomings include: (a) existing maturity frameworks …

Dynamic Multi-Dimensional Numerical Transport Study Of Lithium-Ion Battery Active Material Microstructures For Automotive Applications, Joseph S. Lopata, Taylor R. Garrick, Fengkun Wang, Han Zhang, Yangbing Zeng, Sirivatch Shimpalee

Faculty Publications

In support of GM’s traction battery efforts, we derived and implemented a method to describe the electrochemical performance of a battery cell considering the nuances of the electrode microstructure at the anode and the cathode and the corresponding impact on the electrochemical transport in the solid and liquid phases. To assess the capability of the method, we compared model results from the microstructure framework with the commonly used continuum-level porous electrode model, commonly referred to as the pseudo-2-dimensional model, or the Newman Model. The microstructure modeling framework was applied to simulate the electrochemical and transport processes within the battery cell …

Cellulose-Keratin Supramolecular Composite: Conformation By Combined Fourier Transform Spectroscopy And Partial Least Square Regression Coefficient, Ngesa Ezekiel Mushi Dr

Tanzania Journal of Engineering and Technology (TJET)

Keratin and cellulose are important nano components with excellent mechanical and biological properties. However, the preparation route through dissolution in organic solvents to make manmade materials is challenging because of their intensive bonding interaction characteristics. Structural modification of the natural attributes is difficult to maintain after polymer regeneration. A new technique by a green route was devised to dissolve keratin from wool, hair, and feather with cellulose in situ using 1-Butyl-3-methylimidazolium chloride [BMIm] + Cl- ionic liquid as a solvent. The mixture of keratin and cellulose homogeneously and synergistically resulted in a supramolecular composite film through non-derivatized mechanochemical interactions. The …

Designing And Manufacturing Of Vegetable Slicing Machine, Juma Nuhu Msuya

Tanzania Journal of Engineering and Technology (TJET)

Agro-processing industry is faced with a challenge of slicing of vegetables for immediate consumption. This stems from the fact that the traditional slicing methods use bare hands, and knives. This method is faced with shortcomings of inefficiency, poor hygiene, and significant dangers to injury. If vegetables are not sliced, their drying takes longer, may possibly be spoiled, and cannot be stored for future uses. Therefore, this paper strives to design a vegetable slicing machine to increase the efficiency of the drying process as a post-processing step. The study employed a Pugh’s design model to design the machine and manufacture it. …

Modeling Of The Process Of Measuring Conversion Of The Flow Of Liquid And Gaseous Media By The Method Of Variable Pressure Drop, Shukhrat Manapovich Gulyamov, Elbek Elmirza O'G'Li Ortiqov

Chemical Technology, Control and Management

On the basis of material and heat balances, taking into account the initial and boundary conditions, a mathematical model of the process of measuring the transformation of liquid and gaseous technological media by the method of variable pressure drop is constructed. The analysis of the results of studying the influence of non-stationary flows of a controlled medium on the uncertainty of the results of measuring the flow rate of liquids and gaseous mixtures with a changing hydrodynamic structure of the flow of a controlled medium is performed. A comparative analysis of the calculated and experimental transient processes in the measuring …