Conjugated organic materials comprise a field of materials chemistry focused on the development of semiconducting organic plastics, popular applications of which are plastic solar cells and display technologies. One of the reasons these materials have gained so much attention is that their optical and electronic properties can be tuned through engineering at the molecular level. Thiophene, an aromatic heterocycle, is a popular building block in the synthesis of many conjugated materials, prized for both the ease in which it can be synthetically functionalized and its ability to form highly conductive and low band gap materials. The Rasmussen group has previously reported on the generation of two classes of materials, the inorganic metal thiophenedithiolenes and the fused-ring heterocycle unit thieno[3,4-b]pyrazine (TP), both of which have applications in conducting materials. In an effort to expand upon the applicability and versatility of these materials, a series of interconnected projects were performed to further tune their optical, electronic, and physical (e.g. solubility) properties. This involved synthetic molecular design, including judicious consideration of structure-function relationships, and characterization of the resulting materials. Highlights include a sterics vs. electronics consideration of the catalyzed hydrodebromination of the molecular building-block 2,3,5-tribromothiophene, variation of the coordinating metal in thiophenedithiolenes to tune the optics and electronics, and characterization of the effects of ring-fusion on TP-based terthienyl homopolymers. Additionally, a new application of the TP monomer was found, whereby it was successfully incorporated as a bridging ligand into a multi-metallic Ru(II) supramolecular assembly, which demonstrated good metal-metal communication.

Thesis advisor: James P. Morken / This dissertation describes the development of a method for the stereoselective synthesis of organoboronates and the applications of these products to target-oriented synthesis. The first chapter discusses an investigation of the palladium-catalyzed conjunctive cross-coupling reaction by kinetic analysis. This reaction enables the asymmetric synthesis of organoboronates by utilizing the 1,2-metallate rearrangement of borates as a mechanistic step in a cross-coupling reaction. The second chapter describes the application of the conjunctive cross-coupling reaction to the asymmetric synthesis of tertiary boronic esters. In chapter three, the conjunctive cross-coupling reaction of 1,2-disubstituted alkenyl boronates is presented. Such a substrate class is susceptible to the undesired Suzuki-Miyaura cross-coupling reaction, and this challenge led to the development of a novel diol ligand for boron as an effective solution. The final chapter details the progress toward the total synthesis of the sarcodictyin natural products, which display promising anti-cancer activity. The synthetic route utilizes reactions of organoboronates for powerful C–C bond formations; the construction of a fully-cyclyzed advanced intermediate is achieved in eight steps. / Thesis (PhD) — Boston College, 2020. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

For sites contaminated with chloroethene non-aqueousphase liquids, designing a remediation system that couples in situ chemical oxidation (ISCO) with potassium permanganate (KMnO4) and microbial dechlorination may be complicated because of the potentially adverse effects of ISCO on anaerobic bioremediation processes. Therefore, one-dimensional column studies were conducted to understand the effect of permanganate oxidation on tetrachloroethene (PCE) dechlorination by the anaerobic mixed culture KB-1. Following the confirmation of PCE dechlorination, KMnO4 was applied to all columns at a range of concentrations and application velocities to simulate varied distances from oxidant injection. Immediately following oxidation, reductive dechlorination was inhibited; however, after passing several pore volumes of sterile growth medium through the columns after oxidation, a rebound of PCE dechlorination activity was observed in every inoculated column without the need to reinoculate. The volume of medium required for a rebound of dechlorination activity differed from 1.1 to 8.1 pore volumes (at a groundwater velocity of 4 cm/d), depending on the specific condition of oxidant application.

Software measurement plays an important role in today's software development. Coupling is a measure used in software development that influences the understandability, maintainability and reusability of software components. Many proposals have been made for measuring object-oriented coupling of software components; however, most measures are not useful in the real world of software development. This paper provides a practical guide for evaluating coupling between object-oriented components. This technique is meant for use by software developers who are engaged in the development of software designed to be easy to understand and easy to maintain.

Cross coupling reactions are a well-established tool in modern organic synthesis and play a crucial role in the synthesis of a high number of organic compounds. Their importance is highlighted by the Nobel Prize in chemistry to Suzuki, Heck and Negishi in 2010. The increasing importance of sustainability requirements in chemical production has furthermore promoted the development of cross-coupling protocols that comply with the principles of “Green Chemistry”1. The Sonogashira reaction is today the most versatile and powerful way to generate aryl alkynes, a moiety recurring in many pharmaceutical and natural products. Despite many improvements to the original reaction, reports on generally applicable protocols that work under sustainable conditions are scarce. Our group recently reported an efficient protocol for a copperfree Sonogashira cross-coupling at low temperature, in aqueous medium and with no addition of organic solvents or additives2. The goal of this work was to further investigate the effects of different reaction parameters on the catalytic activity in order to optimize the protocol. Limitations of the protocol were tested in respect to reaction temperature, heating method, atmosphere, base type and amount, catalyst loading, reaction time and work up procedure. The reaction worked successfully under air and results were not affected by the presence of oxygen in the water phase. Among a variety of bases tested, triethylamine was confirmed to give the best results and its required excess could be reduced from nine to four equivalents. Catalyst loading could also be reduced by up to 90%: Good to near quantitative yields for a broad range of substrates were achieved using a catalyst concentration of 0.25mol% and 5 eq of Et3N at 50°C while more reactive substrates could be coupled with a catalyst concentration as low as 0.025mol%. Filtration experiments showed the possibility of a simplified work up procedure and a protocol completely free of organic solvents. This optimized protocol can be applied to a broad range of substrates, delivers high yields, avoids formation of toxic byproducts, works under air and aqueous conditions, allows for simple product isolation and thus meets not only the criteria of “Green Chemistry” but also those of “Click-Chemistry”

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19181号 / 工博第4058号 / 新制||工||1626(附属図書館) / 32173 / 京都大学大学院工学研究科物質エネルギー化学専攻 / (主査)教授 中村 正治, 教授 辻 康之, 教授 小澤 文幸 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

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Spline couplings are used in applications involving high torque; however, due to variations in teeth clearances, all teeth in spline couplings do not engage simultaneously, causing some of the teeth to carry a disproportionately large portion of the total load. Variations in tooth-to-tooth clearances mean the first pair of teeth to engage will carry more load and fail sooner. This has lead to an industry practice of designing splines around the criteria that only 25-50% of the teeth on a spline coupling will engage and carry the load, and the load is generally assumed to be uniformly distributed. This research on tooth engagement is part of an ongoing study sponsored by an industrial partner with the intent to more accurately describe and improve tooth engagement in spline couplings. Tooth engagement in involute spline couplings is difficult to predict due to the complex geometry and even more complex manufacturing processes. Although manufacturing is closely controlled, with precision tooling, engagement problems persist. Presented herein is a detailed study of an involute spline coupling and its associated errors. Mating internal and external involute splines have been analyzed in order to identify variation and error patterns associated with spline coupling assemblies. These error patterns aid in understanding the manufacturing processes and ways in which we can better understand and predict tooth engagement. Spline manufacturing processes were studied in an attempt to relate tooling and processing errors to the resultant error patterns observed in production couplings. Some correlation with tooth engagement measurements have been found, but significant differences remain unexplained. Tooth engagement measurements exhibited anomalous behavior, which raised questions about test apparatus and procedures. The main contributions of this work are: A process for analytically creating torque-deflection curves in any configuration using measurement data, confirmation of the analytical tooth engagement sequence model from measured variation data, a better understanding of the experimental results, how to design future experimental tests, and the importance of early quasi-simultaneous tooth engagement. Several valuable insights have resulted in a better understanding of the mechanics of tooth engagement and load-sharing among spline teeth. The progress made should encourage further study, which may lead to processes which are better understood and controlled, and to designs which are more robust to variation, with more predictable performance and improved load-carrying capacity.

No / The purpose of this article is determining if and how the kinematic relationship between adjacent body segments changes when an individual’s gait pattern is experimentally manipulated can yield insight into the robustness of the kinematic coupling across the associated joint(s). The aim of this study was to assess the effects on the kinematic coupling between the forefoot, rearfoot and shank during ground contact of running with alteration in foot strike pattern. Twelve subjects ran over-ground using three different foot strike patterns (heel strike, forefoot strike, toe running). Kinematic data were collected of the forefoot, rearfoot and shank, which were modelled as rigid segments. Coupling at the ankle-complex and midfoot joints was assessed using cross-correlation and vector coding techniques. In general good coupling was found between rearfoot frontal plane motion and transverse plane shank rotation regardless of foot strike pattern. Forefoot motion was also strongly coupled with rearfoot frontal plane motion. Subtle differences were noted in the amount of rearfoot eversion transferred into shank internal rotation in the first 10–15% of stance during heel strike running compared to forefoot and toe running, and this was accompanied by small alterations in forefoot kinematics. These findings indicate that during ground contact in running there is strong coupling between the rearfoot and shank via the action of the joints in the ankle-complex. In addition, there was good coupling of both sagittal and transverse plane forefoot with rearfoot frontal plane motion via the action of the midfoot joints.

No / Background - Although there is a wealth of research into the kinematic coupling between the foot and shank, it remains unclear whether the relationship is stable across speed and mode of gait. The aim of this study was to determine whether the coupling relationship between the forefoot, rearfoot and shank differed between walking and running, and across different running speeds. Methods Twelve subjects walked/ran barefoot over-ground at one walking and three running speeds. The shank, rearfoot and forefoot were modelled as rigid segments and three-dimensional joint kinematics were determined using a seven camera ProReflex system. Coupling between the forefoot, rearfoot and shank was assessed using cross-correlation and vector coding techniques. Findings Cross-correlation of rearfoot eversion/inversion with shank internal/external rotation was lower in walking (r=0.49) compared to running (r>0.95). This was also the case between rearfoot frontal plane and forefoot sagittal plane motion (walking, r=¿0.80; running, r=¿0.96). Rearfoot frontal plane and forefoot transverse plane cross-correlation was high in both running and walking (r>0.90), but there was little evidence of any coupling between rearfoot frontal plane and forefoot frontal plane motion in any condition. No differences in cross-correlations were found between the three running speeds. Interpretation Kinematic coupling between the forefoot, rearfoot and shank was weak during walking relative to running. In particular, the low cross-correlation between rearfoot eversion/inversion and shank internal/external rotation during walking implies the two motions are not rigidly linked, as has been assumed in previous injury models.