Predicting Ion Exchange Bead Rise during Backwash Flow

Separation of cationic and anionic resin is an important step in mixed bed ion exchange operation. Prior to regeneration good separation of the two resins reduces cross contamination. Inefficient separation of the resins also leads to loss of capacity. By accurately predicting the height of the resin interface, the separation of the resins can be improved. This study proposes a bed expansion model that accurately predicts the bed expansion height.School of Chemical Engineerin

Myanmar Undergoing an Exciting Phase: An Indian Traveller's Impression

After collecting my baggage, I joined other co-passengers to face the immigration counter at Yangon airport. Being on a research trip, I was expecting the usual grilling and curious questions from immigration officials. The grilling was particularly more intense during my previous visit to Bangladesh. For almost half an hour, the customs officials posted at the Dhaka airport had interviewed me to get a clearer understanding on the exact purpose of my visit to Bangladesh

Genomic characterization and epidemiology of an emerging SARS-CoV-2 variant in Delhi, India

Delhi, the national capital of India, experienced multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreaks in 2020 and reached population seropositivity of >50% by 2021. During April 2021, the city became overwhelmed by COVID-19 cases and fatalities, as a new variant, B.1.617.2 (Delta), replaced B.1.1.7 (Alpha). A Bayesian model explains the growth advantage of Delta through a combination of increased transmissibility and reduced sensitivity to immune responses generated against earlier variants (median estimates: 1.5-fold greater transmissibility and 20% reduction in sensitivity). Seropositivity of an employee and family cohort increased from 42% to 87.5% between March and July 2021, with 27% reinfections, as judged by increased antibody concentration after a previous decline. The likely high transmissibility and partial evasion of immunity by the Delta variant contributed to an overwhelming surge in Delhi

Modeling Fatigue Behavior of 3D Printed Titanium Alloys

Indiana University-Purdue University Indianapolis (IUPUI)Repeated loading and unloading cycles lead to the formation of strain in the material which causes initiation of the crack formation this phenomenon is called fatigue. Fatigue properties are critical for structures subject to cyclic load; hence fatigue analysis is used to predict the life of the material. Fatigue analysis plays an important role in optimizing the design of the 3D printed material and predicting the fatigue life of the 3D printed component. The main objective of this thesis is to predict the fatigue behavior of different microstructures of Ti-64 titanium alloy by using the PRISMS-Fatigue open-source framework. To achieve this goal Ti-64 microstructure models were created using programming scripts, then the structures were exported to a finite element visualization software package, with all the required properties embedded in the pipeline. The PRISMS-Fatigue framework is used to conduct a fatigue analysis on 3D printed materials, using the Fatigue Indicator Parameters (FIP), which measure the driving force of fatigue crack formation in the microstructurally small crack growth. Three different microstructures, i.e., cubic equiaxed, random equiaxed, and rolled equiaxed microstructures, are analyzed. The FIP results show that the cubic equiaxed grains have the best fatigue resistance due to their isotropic structural characteristics. Additionally, the grain size effect using 1 and 10 micrometers is investigated. The results show that the 1 micrometer grain size cubic equiaxed microstructure has a better fatigue resistance because as grains are small and they have a higher mechanical strength

India's Decision Making on Cross-Border Natural Gas Pipelines (1989-2012)

In the last two decades, cross-border gas pipelines have become an integral part of discourse on India’s energy security. Successive reports from the government and the private sector have envisaged an important role for cross-border gas pipeline projects in India. After engaging in negotiations for several years, the Indian Government finally joined the Turkmenistan, Afghanistan, Pakistan and India (TAPI) gas pipeline over the Iran–Pakistan–India pipeline (IPI) and the Myanmar– Bangladesh–India pipeline (MBI). Several critics of this project have questioned this decision of the Indian Government to join TAPI due to the huge levels of risks involved and the project’s commercial unviability. The article is an attempt to understand the decision-making process of the Indian Government on cross-border gas pipeline projects and its rationale for choosing a seemingly riskier project like the TAPI pipeline and letting go of the other two pipeline projects. The article makes an attempt to conduct a detailed discussion around such factors that contributed to India’s decision making on these projects

India's Energy Security Concerns and Decision Making: Case Studies of Cross-Border Natural Gas Pipelines

Several studies and policy reports in the past have documented and acknowledged the importance of energy security for India’s national development. To ensure an ambitious economic growth and development, a robust energy security decision-making and planning becomes critical. Decision making on energy security is often perceived and studied from the lens of technology and economics. Such studies often ignore the underlying geopolitical factors that play an important role in influencing outcomes of proposed energy projects. More often than not, as seen in the case of cross-border pipeline projects, the underlying geopolitics supersedes other factors such as commercial merit (Masuda, 2007). In case of India, geopolitical changes in its neighborhood and abroad; evolving discourse on clean and sustainable energy; and changing nature of market conditions have a strong and unpredictable influence on India’s energy security. Additionally, the dynamic nature of India’s bilateral relations, presence of non-state actors, geopolitics and influence of external powers in India's neighborhood have made decision making on energy security more complicated and challenging. As India contemplates ways and means to source natural gas from its neighborhood through cross border natural gas pipelines, the study of geopolitics and the influence of the above-mentioned factors on India’s natural gas trade assumes increasing importance. Within this context, the doctoral thesis analyses India’s three cross-border natural gas pipeline projects, viz, Myanmar-Bangladesh-India gas pipeline, Iran-Pakistan-India gas pipeline and the Turkmenistan-Afghanistan-Pakistan-India gas pipeline projects. It explores the rationale behind India's decision making to join or refrain from joining the above-mentioned pipeline projects. Secondly, through these case studies, efforts were made to unravel the role of geopolitics on India’s energy security decision making. Thirdly, by employing the conditions laid by Japanese scholar Tatsuo Masuda (2007), the thesis makes an assessment on the viability and non-viability of the proposed cross-border natural gas pipeline projects. Additionally, by borrowing the framework of Allison and Zelikow's (1999) Rational Actor Model theory, the thesis explores those specific factors that influenced India's decision making on cross-border natural gas pipeline projects. Through the three case studies, the doctoral research demonstrates that while performing a cost-benefit analysis of cross-border energy projects, there is also a need to incorporate geopolitical factors to ensure a more realistic and pragmatic assessment. The doctoral thesis documents and analyses the role of non-state actors in influencing decision making on India’s energy security. As India expands its energy engagement with its neighborhood, this factor would continue to play a significant role in influencing decision making on future projects. The thesis has also identified the critical role of bilateral relations among individual participating countries as a crucial parameter for the construction and sustainability of cross-border pipeline projects. After perusing through three proposed cross-border natural gas pipeline projects, the thesis examines prospective opportunities for India’s energy security and identifies strategies that a consumer country like India must adopt in order to build sustainable energy linkages for the coming decades

Flexibility from Participating Nations – Key to TAPI’s Success

In the last one month, two significant developments have brought the TAPI project back into the lime light. Reportedly, Dragon Oil evinced interest in participating in the TAPI project’s pipeline construction1. This is a major breakthrough for this ambitious, multilateral project that was facing the prospect of a silent burial a few months ago due to the absence of any leader for the consortium. But with Dragon Oil’s participation, construction of the proposed project can be expected to move ahead with full speed2. Following closely on the heels of this development, the four nations who have invested in the project participated in a ground-breaking ceremony in Ashgabat to commence pipeline construction3. But, despite the progress made in the last few weeks, the project still faces certain commercial constraints that have the potential to stall the pipeline construction. Foremost among these revolves around gas pricing concerns, primarily of India and Pakistan. As per recent reports in The Economic Times on November 9, 2015, India apparently is not happy about the unit price of gas quoted by Turkmenistan and is hoping to re-negotiate the issue4. Couple of years ago, similar concerns associated with gas prices for TAPI pipeline project were echoed by the Sustainable Development Policy Institute, an Islamabad based think tank5. It will be interesting to see how the Turkmen government responds to this fresh Indian move on gas price negotiations. For the continued sustenance of this project, it would be imperative for the Turkmen government to show some degree of flexibility on gas pricing. If that does not happen, it will perhaps force India to reconsider its participation in the project

Probing a Sea option for Turkmen Gas

There is both an element of continuity and change in the NDA-led Indian Government towards the Turkmen gas pipeline project. Continuity because during his recent visit to Turkmenistan, Indian Prime Minister Narendra Modi vociferously ‘pitched’ for a speedy realisation of the TAPI gas pipeline project and remarked that the stakeholders in the project must consider a ‘land-sea route’ option instead of an overland route which passes through Afghanistan and Pakistan [1]. And change because it is a major departure from the traditional discourse on the TAPI pipeline project which has always advocated an overland route passing through Pakistan. Several analysts within India had questioned the viability of an overland route passing through southern Afghanistan and northern Balochistan

Machining assessment of nano-crystalline hydroxyapatite bio-ceramic

Master of ScienceDepartment of Industrial & Manufacturing Systems EngineeringShuting LeiMalgorzata RysThe demand of synthetic implants for good quality of life is high and increasing continuously due to limitations of autogenous bone grafting. Development of various synthetic bio materials and their manufacturing methods in the fields of orthopedics and dentistry has been done and still under way. Close physical properties with human bone make sintered hydroxyapatite (HAP) a suitable bioceramic material for hard tissue replacement. Newly developed fully dense nanocrystalline hydroxyapatite (nHAP) bioceramic has better mechanical properties than porous hydroxyapatite and has potential to be used alone, without metallic support in certain applications. When being used as implant devices in the human body, the nHAP bioceramic needs to be machined to the closest possible configuration with minimal surface roughness. This study investigates the machinability of nHAP bioceramic in milling operations. Efforts are focused on the effects of various machining conditions on surface integrity. Surface roughness is measured using a surface profilometer and the machined surface is observed using an optical microscope and a scanning electron microscope (SEM). Chip morphology and tool wear are examined using an optical microscope. Machined surface analysis showed that the surface integrity was good and the required surface roughness value (R[alpha]) of 1 - 1.5 [mu]m was achieved in many experiments. It was found that material removal is caused by brittle fracture without plastic flow. A first order surface roughness model for the end milling of nHAP under dry condition has been described. The mathematical model for surface roughness has been developed based on the cutting parameters: cutting speed, feed and depth of cut. The effects of these parameters on surface roughness have been studied using factorial designs and response surface method. Model analysis showed that all three cutting parameters have significant effect on surface roughness. However the current model has limited statistical power for prediction purposes and it demands a higher order model for accurate prediction of surface roughness value