Mukund Sibi - NDSU Publications
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Item It's Happening at State: March 15, 2013(North Dakota State University, 2013-03-15)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: October 31, 2012(North Dakota State University, 2012-10-31)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: October 15, 2012(North Dakota State University, 2012-10-15)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: September 14, 2012(North Dakota State University, 2012-09-14)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: August 15, 2012(North Dakota State University, 2012-08-15)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: May 15, 2012(North Dakota State University, 2012-05-15)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: April 30, 2012(North Dakota State University, 2012-04-30)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: February 15, 2012(North Dakota State University, 2012-02-15)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item Synthesis and Utilization of Si6H12 and Si6X12 (X = Cl, Br) for the Generation of Novel Silicon Materials(North Dakota State University, 2017) Frohlich, Matthew T.Cyclohexasilane (Si6H12) and its derivatives, Si6X12 (X = Cl, Br), have chemical and physical properties different from linear and branched polysilanes, thus creating interest in their use as starting materials for a variety of applications. The liquid nature and lower activation energy of Si6H12 give it advantages as a starting material for silicon based materials including quantum dots (SiQDs), nanorods (SiNRs) and nanowires (SiNWs), as well as novel processing methods such as roll to roll deposition of silicon thin films. The electronegative elements on Si6X12 create Lewis acid sites above and below the ring, giving it the ability to form novel salts and 1-dimensional stacked polymers. This work developed a new route toward Si6H12 and Si6Cl12 by focusing on the production of the precursor [Si6Cl142-] dianion salts and studying their physical and chemical properties. This thesis also describes the preparation of novel Si6X12 based materials.Item Silicon Nanocrystals: Optical Properties and Self Assembly(North Dakota State University, 2018) Brown, SamuelSilicon nanocrystal’s (SiNCs) size dependent optical properties and nontoxic nature portend potential applications across a broad range of industries. With any of these applications, a thorough understanding of SiNC photophysics is desirable to tune their optical properties while optimizing quantum yield. However, a detailed understanding of the photoluminescence (PL) from SiNCs is convoluted by the complexity of the decay mechanisms, including a stretched-exponential relaxation and the presence of both nanosecond and microsecond decays. In this dissertation, a brief history of semiconductor nanocrystals is given, leading up to the first discovery of room temperature PL in SiNCs. This is then followed by an introduction to the various nanocrystal synthetic schemes and a discussion of quantum dot photophysics in general. Three different studies on the PL from SiNCs are then presented. In the first study, the stretched nature of the time dependent PL is analyzed via chromatically-resolved and full-spectrum PL decay measurements. The second study analyzes the size dependence of the bimodal PL decay, where the amplitude of the nanosecond and microsecond decay are related to nanocrystal size, while the third project analyzes the temperature and microstructure dependencies of the PL from SiNC solids. After an indepth look at the PL from SiNCs, this report examines preliminary results of SiNC and silver nanocrystal self-assembly. When compared to metal and metal chalcogenide nanoparticles, there is a dearth of literature on the self-assembly of SiNCs. To understand these phenomena, we analyze the size dependent ability of SiNCs to form a ‘superlattice’ and compare this with silver nanocrystals. Although the results on self-assembly are still somewhat preliminary, it appears that factors such as SiNC concentration and size dispersity play a key role in SiNC self-assembly, while suggesting intrinsic differences between the self-assembly of SiNCs and silver nanocrystals. Finally, at the end of this dissertation, a corollary project is presented on the computational analysis of fluorescent silver nanoclusters (AgNCs). Due to their small size and non-toxic nature, AgNCs are an ideal fluorophore for biological systems, yet there is a limited understanding of their photophysics, which is the focus of this part of the dissertation.Item NDSU Magazine : Spring 2001(North Dakota State University, 2001)Item NDSU Magazine : Spring 2008(North Dakota State University, 2008)Item Pilot Scale Production, Characterization, and Optimization of Epoxidized Vegetable Oil-Based Resin(North Dakota State University, 2015) Monono, Ewumbua MenyoliNovel epoxidized sucrose soyate (ESS) resins perform much better than other vegetable oil-based resins; thus, they are of current interest for commercial scale production and for a wide range of applications in coatings and polymeric materials. However, no work has been published that successfully scaled-up the reaction above a 1 kg batch size. To achieve this goal, canola oil was first epoxidized at a 300 g scale to study the epoxidation rate and thermal profile at different hydrogen peroxide (H2O2) addition rates, bath temperatures, and reaction times. At least 83% conversion of double bonds to oxirane was achieved by 2.5 h, and the reaction temperature was 8-15 oC higher than the water bath temperature within the first 30-40 min of epoxidation. A 38 L stainless steel kettle was modified as a reactor to produce 10 kg of ESS. Twenty 7-10 kg batches of ESS were produced with an overall 87.5% resin yield and > 98% conversion after batch three. The conversion and resin quality were consistent across the batches due to the modifications on the reaction that improved mixing and reaction temperature control within 55-65 oC. The total production time was reduced from 8 to 4 days due to the fabrication of a 40 L separatory funnel for both washing and filtration. A math model was developed to optimize the epoxidation process. This was done by using the Box-Behnken design to model the conversion at various acetic acid, H2O2, and Amberlite ratios and at various reaction temperatures and times. The model had an adjusted R2 of 97.6% and predicted R2 of 96.8%. The model showed that reagent amounts and time can be reduced by 18% without compromising the desired conversion value and quality.Item It's Happening at State: August 31, 2011(North Dakota State University, 2011-08-31)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: May 31, 2011(North Dakota State University, 2011-05-31)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: May 13, 2011(North Dakota State University, 2011-05-13)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: October 06, 2004(North Dakota State University, 2004-10-06)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: July 21, 2004(North Dakota State University, 2004-07-21)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: March 17, 2004(North Dakota State University, 2004-03-17)Provides summary information of news and events of interest to the faculty and staff of NDSU.Item It's Happening at State: August 24, 2005(North Dakota State University, 2005-08-24)Provides summary information of news and events of interest to the faculty and staff of NDSU.
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