Patterning Synthesis of Lead Halide Perovskites Toward Photonic Application

Lead halide perovskites (LHPs) are a fascinating class of photonic materials with the potential to revolutionize various optoelectronic applications. Their diverse crystal structures, ranging from 0D to 3D configurations, offer a unique combination of properties, including high tunability and ease of synthesis. However, their inherent instability and the difficulty of patterning them into sophisticated photonic structures using conventional methods present a significant hurdle to their widespread applications. This thesis addresses these challenges by proposing a novel synthesis method that combines soft lithography and self-assembly. By utilizing a patterned template with controlled wettability, precise manipulation of LHP crystal formation is achieved, enabling the fabrication of patterned LHP structures with high crystalline quality. This innovative approach offers a scalable and practical pathway for incorporating LHPs into advanced photonic devices. This thesis will comprehensively explore LHPs, characterizing their structures, investigating their potential, and validating a novel patterning method. This comprehensive analysis aims to advance the understanding and utilization of LHPs, paving the way for their integration into next-generation photonic devices. Advisor: Yanan (Laura) Wan

CELL COMPATIBILITY ANALYSIS OF POMATO BASED ON SEEDLING AGE AND FERTILIZER TREATMENT

A Thesis submitted to the Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka In partial fulfillment of the requirements For the degree of MASTER OF SCIENCE IN GENETICS AND PLANT BREEDING SEMESTER: JULY- DECEMBER, 2015An experiment was conducted at the experimental field of Horticultural farm of Sher-e-Bangla Agricultural University, Dhaka, during November 2014 to April 2015. Cell compatibility of tomato and potato by making pomato plants was evaluated in six grafting combinations (tomato grafted on potato) and laid out in RCBD design with three replications. Three potato (Solanum tuberosum L.) and two tomato genotypes (Solanum lycopersicum L) were used for grafting in all possible combinations. Two treatments, viz. two seedling age of tomato and three fertilizer doses were used to identify best compatible grafting. The compatibility was evaluated through the observation of yield and sixteen yield contributing characters under different treatments. Cleft grafting was used to assess the magnitude of different fertilizers doses effect on different pomato genotype for high yield of tomato and tuber. The analysis of cell compatibility revealed that the pomato G6 (BARI tomato-11 grafted on Asterix) showed the best performance for total tuber yield (13.8 ton/ha) followed by pomato G3 (BARI tomato-2 grafted on Asterix) which showed the total tuber yield 9.27 ton/ha. Both the pomato genotypes for giving high tuber yield were grafted with 25 days old seedling of tomato and the applied fertilizer dose was 390 Kg/ha of urea, 280 Kg/ha of TSP, 312 Kg/ha of MoP, 140 Kg/ha of gypsum and 13000 Kg/ha of cowdung. The pomato G3 also showed the best performance for total tomato yield (41.65 ton/ha) when grafted with same age of seedling of tomato and with the same fertilizer doses as mentioned for total tuber yield. Hence, pomato G3 (BARI tomato-2 grafted on Asterix) could be recommended to the farmers for grafting and cultivation for total yield including both potato and tomato when grafted with young tomato seedling of 25 days old and with the fertilizer dose of 390 Kg/ha of urea, 280 Kg/ha of TSP, 312 Kg/ha of MoP, 140 Kg/ha of gypsum and 13000 Kg/ha of cowdung

Digital learning technology blend in assessment activities of higher education:a systematic review

Online teaching and assessment in higher educational institutions have become the new normal due to the COVID-19 pandemic. This chapter presents a systematic literature review on various digital assessment activities as the diversity of student assessment and feedback technologies cannot be identified from existing literature. Applying Creswell’s five steps and PRISMA guidelines, 40 peerreviewed articles are reviewed. The synthesis of the digital learning technologies for student assessment and feedback are classified into three categories: regular online examinations, alternative online assessment strategies, and ethical assessment. The authors focus on the recent digital technologies for student assessment as well as feedback and recommend empirical investigation on the functionalities and pedagogical designs.<br/

Thermal Hydraulic Analysis for Different Subchannels of Generic VVER-1200

The demand for nuclear energy is steadily increasing all over the world. Most nuclear power is used for peaceful applications such as power generation, healthcare, agriculture, food security, industry, and research. One of the primary applications of nuclear energy is the generation of electricity through nuclear power plants based on nuclear reactors. Many developing countries around the world (such as Bangladesh) are moving toward nuclear power plants because they have huge advantages, including low-cost energy, reliable energy sources, zero carbon emissions, and high energy concentration. As a result, the demand for nuclear reactor protection and operational protection of nuclear power plants is growing rapidly around the world. To meet this demand, nuclear reactor safety as well as nuclear reactor safety parameters must be analyzed. Our research included an examination of the turbulent flow of coolant water into different subchannels of the VVER-1200 nuclear reactor at a pressure of approximately 16 MPa. The Rooppur Nuclear Power Plant, which is currently being built at Ishwardi, an upazila (i.e., subdistrict) of the Pabna District on the bank of the river Padma in Bangladesh, has a VVER-1200 reactor with geometry details of fuel rods, a coolant subchannel, and other operating parameters that are similar to those of that reactor. We used the ANSYS turbulence model to analyze the three subchannels—central, corner, and edge—using three fuel rods. The effects of turbulent flow on temperature distribution, velocity variance, pressure drop, friction factor, Reynolds number, and more were examined in different subchannels of the VVER-1200. The thermal-hydraulic characteristics of coolant water were also investigated to evaluated safety concerns, such as hot spots in the coolant channel and departure from nucleate boiling

Neuroendocrine Tumor of the Ampulla of Vater: A Case Report

Neuroendocrine tumors (NETs) of the ampulla of Vater are extremely rare. Here, we discuss the clinical presentation, diagnostic challenges, and treatment options of a recently experienced case of NET of the ampulla of Vater in light of the literature. A 56-year-old woman presented with recurrent upper abdominal pain. Ultrasonography (USG) of the whole abdomen showed multiple gallstones along with a dilated common bile duct (CBD). For evaluating the dilated CBD, a magnetic resonance cholangiopancreatography was performed, which revealed the double-duct sign. Subsequently, an upper gastrointestinal endoscopy showed a bulged-out ampulla of the Vater. Biopsy and histopathological examination of the growth yielded the diagnosis of adenocarcinoma. A Whipple procedure was performed. Macroscopically, a 2 cm growth was noted involving the ampulla of Vater, and microscopic findings were consistent with a well-differentiated NET, grade 1 (low grade). The diagnosis was further confirmed by immunohistochemical staining (pan-cytokeratin positive, synaptophysin positive, and focally chromogranin positive). Her postoperative course was uneventful except for delayed gastric emptying. A detailed evaluation and a high index of suspicion are required for the diagnosis of this rare tumor. Treatment is relatively easier after a proper diagnosis

Education system in Bangladesh amid COVID-19:traditional scenario, emergency protocols, challenges and a proposed sustainable conceptual framework

This study demonstrates how significantly the COVID-19 pandemic has affected Bangladesh’s formal education system. Despite the fact that Bangladesh introduced Information and Communication Technology (ICT) in educational practices before the pandemic, effective ICT deployment could not be integrated at all levels. Even though online classes and other print- and electronic media-based approaches evolved into the “new normal” in an effort to address the difficulties brought on by the pandemic, both teachers and students have faced and continue to encounter many challenges. A convergent parallel mixed method design was followed for this study. Data were collected from 205 Bangladeshi students and 50 Bangladeshi teachers through semi-structured questionnaires. In addition, 11 parent interviews and 12 Key Informant Interviews were conducted. According to the findings, the lack of proper training for teachers, poor socio-economic conditions, lack of internet availability and speed, the shortage of ICT equipment, students not being technologically exposed, and the disruption of electricity are major issues hindering the fruitful implementation of online education. Creating an ICT framework, providing subsidised internet for students and instructors for instructive purposes, promoting alternative means to carry on formal education, dedicating instruction hours in TV and radio channels, ensuring proper IT infrastructure and tools, and taking initiatives to promote the learning management system can play a significant role in creating the ideal environment to promote online education. In summary, this study suggests a holistic framework to continue formal teaching-learning in different levels of education to achieve sustainable development goals (SDG) without any disruption in emergency contexts such as the COVID-19 pandemic

Moderated Mediating Effect of Behavioral Psychology on Generation Z’s Selfie-Posting Behavior: A Two-Stage Analytical Approach

Received 11 February 2024. Accepted 3 August 2024. Published online 21 October 2024.The purpose of this study was to investigate the mediating and moderating effects of body appreciation and exhibitionism on the relationships between self-esteem, narcissism, and Selfie-Posting Behavior (SPB), as well as on the moderating effect of attitude towards selfies (ATS) from the Generation Z perspective. The research comprised 414 samples through convenience sampling. The empirical data were analyzed using a hybrid SEM-artificial neural network (SEM-ANN) approach. The sensitivity analysis outcomes discovered that body appreciation has the most considerable effect on the SPB, with 89.18% normalized importance, followed by narcissism (87.02%), exhibitionism (72.66%), and self-esteem (48.95%). Body appreciation and exhibitionism independently and sequentially mediated the relationships between self-esteem and SPB, as well as narcissism and SPB. In addition, attitude moderated the relationship between exhibitionism and SPB but not the relationship between body appreciation and SPB. The study results emphasize the importance of recognizing the moderating mechanisms that affect the mediated pathways between self-esteem and SPB, as well as between narcissism and SPB. Based on these findings, the study outlined several applicable ramifications for educators, professionals, service providers, designers, and developers