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In this study, a new experimental approach is proposed to investigate the absorption properties of some selected retail paper towels. The samples were selected from two important manufacturing processes, conventional wet pressing (CWP) considered value products, and through air drying (TAD) considered as high or premium products. The tested liquids were water, decane, dodecane, and tetradecane with the total volumes in micro-liter range. The method involves the point source injection of liquid with different volumetric flowrates, in the nano-liter per second range. The local site for injection was chosen arbitrarily on the sample surface. The absorption process was monitored and recorded as the liquid advances, with two distinct imaging system methods, infrared imaging and optical imaging. The microscopic images were analyzed to calculate the wetted regions during the absorption test, and the absorption diagrams were generated. These absorption diagrams were dissected to illustrate the absorption phenomenon, and the absorption properties of the samples. The local (regional) absorption rates were computed for Mardi Gras and Bounty Basic as the representative samples for CWP and TAD, respectively in order to be compared with the absorption capacity property of these two samples. Then, the absorption capacity property was chosen as an index factor to compare the absorption properties of all the tested paper towels.

The aim of this thesis was to examine the ability of metal organic frameworks (MOFs) to store and controllably release biologically significant amounts of nitric oxide (NO). Initial work involved the synthesis of a series of isostructural MOFs, known as M-CPO-27, which display coordinatively unsaturated metal sites (CUSs) when fully activated (guest solvent molecules both coordinated and uncoordinated to the metal atom are removed). Two of these frameworks (Ni and Co CPO-27) displayed exceptional performance over the entire cycle of activation, storage and delivery showing the largest storage and release of NO of any known porous material (up to 7 mmolg⁻¹). These frameworks would therefore be considered for initial research into the formulation of MOFs, for possible use in medical applications. It was shown that they still release large amounts of NO even when placed inside porous paper bags, creams or hydrocolloids. The other versions of M-CPO-27 also displayed significant adsorption of NO however they show poor total NO release. It was also shown that it is possible to synthesise both Ni and Co CPO-27 using microwave synthesis without any detrimental effect to the porous structure. Several iron-based MOFs were also investigated for NO storage and release. The results showed that Fe MIL-88 based structures adsorb good amounts of NO but only release a small amount of the irreversibly adsorbed NO. Two successfully amine grafted giant pore MOFs were then investigated to attempt to improve the NO adsorption and release. This result was not observed however, due to the poor total amine grafting coverage and pore blockage resulting from the amines. In-situ IR studies reveal that when exposed to NO, activated Fe MIL-100 forms a chemical bond with the NO. The studies also displayed that when water is then allowed to attempt to replace the NO that only a small amount of NO is actually released, the majority of the NO either remains chemically bonded to the Fe atom or forms N₂O in conjunction with a Fe-OH group. Other MOFs were also successfully synthesised and characterised for NO storage and release. Both Ni succinate and Ni STA-12 display good adsorption and excellent release of NO. This indicates that Ni based MOFs show the best results for NO adsorption and release. In the conclusion of the thesis I am able to categorise the NO release ability of MOFs based on composition and formulate a theory as to why this happens.

Chapter 1: Introduction to the current state of the field of Covalent Organic Frameworks (COFs), covering methods of synthetic control over the structure, chemistry, and reactivity of these framework materials. Emphasis is given on the nature of the field as an extension of organic synthesis into two- and three-dimensional solids. Chapter 2: In this chapter, I describe the first postsynthetic modification of a COF’s linkage, the functional groups generated upon reticulation of its building units into an extended network. Specifically, a two-dimensional imine-linked COF of kgm topology was converted to an amide-linked material of the same structure and connectivity by Pinnick-type oxidation of its imine linkages. The resulting amide-linked material possesses enhanced stability in aqueous acid and base relative to its imine-progenitor. This postsynthetic approach allows access to novel COF linkages without the need to determine conditions for which an ordered network of that linkage can be formed directly, decoupling the relationship between crystallinity and linkage reversibility previously inherent in COF chemistry. Chapter 3: In this chapter, I describe the synthesis of cyclic carbamate and thiocarbamate-linked COFs, made from the multistep postsynthetic modification of an isostructural imine-linked framework. Unlike linkages previously accessed through postsynthetic modification, these are the first linkages accessible only through multiple synthetic steps in the solid. Furthermore, each step along the synthetic route was analyzed by 15N multiCP-MAS NMR spectroscopy, for the first time allowing quantitative analysis of postsynthetic modifications in COFs. This work sets a new standard for the execution and evaluation of multistep chemical transformations of solids, and in doing so lays the groundwork for further exploration of solid-state organic synthesis.Chapter 4: A new three-dimensional COF, COF-432 was synthesized, whose structure violates commonly accepted heuristics for the prediction of COF structures from their building units. COF-432 possesses a topology previously reported in COFs or metal-organic frameworks (MOFs). Additionally, in testament to the value of expanding the structural diversity of COFs, COF-432 has a type-IV water adsorption isotherm with a sharp uptake at 35% relative humidity, suggesting it may be applicable in water capture technologies. Chapter 5: The interdisciplinary nature of COF chemistry, and reticular chemistry in general, makes these fields effective teaching tools in training undergraduate students for research in graduate school and beyond. In this chapter, a teaching program is described in which thirty students from around the world participated in a lab and lecture course covering concepts, synthetic techniques, and characterization techniques used in reticular chemistry. Students also participated in a poster session and simulated paper submission exercise, giving them experience not just in carrying out research, but also communicating the results of that work to the greater scientific community.

This dissertation considers the development of porous carbon materials as the substrates for Al deposition/dissolution in an Al based ionic liquid flow battery (ILFB) and demonstration of an Al based hybrid supercapacitor. The Aluminum chloride/ 1-ethyl-3-methylimidazolium chloride chloroaluminate ionic liquid is utilized as the electrolyte for these Al based energy storage devices. The ILFB has less capital cost than the all-vanadium redox flow battery because of the inexpensive AlCl3. The feasibility to equip a tank of solid aluminum chloride in an ILFB system aiming to improve energy density is investigated. A critical range of temperature data (50-130 celsius degree) for aluminum chloride dissolution and precipitation from saturated chloroaluminate ionic liquids is measured by differential scanning calorimetry. The process of Al deposition on porous carbon materials is investigated in the static electrolyte and a flow-through cell aiming to improve the current density, the amount of Al deposits stored in substrates and limit the dendrite growth. Fourier transform infrared spectroscopy and scanning electron microscope are applied to characterize the Al deposits on the porous carbon materials. By the flow-through method providing enhanced diffusion to porous carbon materials, the current density of Al deposition on carbon paper is remarkably higher than that on Al disk. However, dendrites prefer to grow on the Al disk substrate. The electrolyte flow rate and the flow direction also play important roles in determining current densities and dendrite formation for Al deposition on porous carbon materials. We successfully demonstrate an Al based hybrid supercapacitor using high surface area carbon materials such as graphene and activated carbon. The activated carbon is preferred because of less catalytic ability to evolve chlorine. The mismatch between the small pore size of activated carbon and the large ion size of complex ions results in the high charge-transfer resistance measured by the electrochemical impedance measurements. The wettability of electrodes determined by different polymer binders, Polytetrafluoroethylene and the aqueous base modified styrene butadiene rubber, has a significant effect on specific capacitance of activated carbon. The hydrophilic property of SBR may promote the entrance of ions to the micropores of activated carbon.

Freezing soils are significant due to their wide occurrence in nature. A thorough understanding of their behaviors is challenged by their susceptibilities to multiphysical processes as the result of their porous nature. Further advancements in research related to freezing soils call for holistic simulation techniques and innovative instruments. This study reviewed previous research to lay down a knowledge base for investigating the behaviors of porous materials under frost action. Based on the review, it was concluded that more comprehensive multiphysics frameworks and innovative characterization techniques are highly desirable for further advancing this topic. For the purpose, a comprehensive multiphysics framework was developed by integrating and taking advantage of the knowledge base. The new model couples heat equation for heat transfer, modified Richards’ equation for fluid transfer, and mechanical constitutive relationships. Auxiliary relationships, such as the similarity between drying and freezing processes and the Clapeyron equation for phase equilibrium during phase transition, were utilized to describe the frost action. The coupled nonlinear equation system was solved under typical boundary conditions using the finite element method. To further test the performance and applicability of the model, the simulation code was implemented and verified on instrumented pavement sections and in typical buried pipe scenarios. For pavements, both flexible and rigid pavements were simulated. The simulation results were compared with instrumented data on these test pavements. For pipes, cases involving static and dynamic loads were studied, respectively. Phenomena typical of pipe-soil interactions under frost action were reproduced and several detrimental factors on the safety and durability of buried pipes under frost action were identified. On the experimental side, a new instrumentation technique, i.e., thermo-Time Domain Reflectometry (TDR) sensor, was developed to characterize the behaviors of freezing soils. The thermo-TDR combines temperature sensors and a conventional TDR module. The TDR module and algorithm measured the bulk free water content of soils during the freezing/thawing process, while the built-in thermocouples measured the variation of the internal temperature. The Soil Water Characteristic Curve (SWCC) was obtained from the simultaneously measured TDR and temperature data. The new characterization technique was verified by the filter paper method (ASTM D5298).