I. Synthesis of Diverse Structures from Quinone Monoketal and Quinone Imine Ketal with Efficiency and Control II. Synthetic Study of Phalarine

Quinonoids are quinone derivatives that have carbonyl or carbonyl equivalent and even number of double bonds embedded in six member rings. As a result of the intrinsic α,β-unsaturated ketone or imine structures, quinonoids, such as quinone monoketals, quinols, quinol ethers and quinone imine ketals, can accommodate a wide range of reactions including 1,2-additon, 1,4-addtion, SN2’ reaction (allylic substitution) to the α-carbon of the carbonyl or imine and cycloaddition reactions (e.g. Diels-Alder reaction). Quinonoids are effective building blocks for synthesizing heterocycles, which are ubiquitous in pharmaceutically useful agents. Developing new quinonoid based methodologies is essential to expanding the boundary of synthetic organic chemistry and providing viable pathway to synthesis of molecules of pharmaceutical interests. The first three chapters of this thesis describes three methodologies on synthesis of diverse heterocycles from quinone monoketal and quinone imine ketal, the process of methodology development and how each methodology inspired the consequential methodology. Besides the research on quinonoids based synthetic methodologies, we have also been working on a concise formal synthesis of an indole alkaloid–phalarine. This project, though not finished, afforded interesting products, that provided mechanistic insight into the reactivity and chemoselectivity of tetrahydro-beta-carboline. This project is covered in chapter 4. Chapter 1 Previously our group has developed a variation of Fischer indole synthesis using quinone monoketal and aliphatic hydrazine. Literature reported reaction of quinone monoketal and nucleophiles, such as hydrazine, amine and hydroxylamine, gave either 1,2-addition or 1,4-addition products. Due to lack of studies on reaction of quinone monoketal and N-protected hydroxylamine, we were intrigued to explore this reaction. A probe into the reaction of quinone monoketal and BnNHOH gave rise to an unexpected product, which was characterized as a bridged isoxazolidine. This isoxazoli- dine compound, which reveals to be the double Michael addition product of BnNHOH to quinone monoketal, provides an alternative to conventional synthesis of isoxazolidines by nitrone-alkene cycloaddition. To explore the scope of this reaction, a number of quinone monoketals were reacted with BnNHOH or BocNHOH and a wide range of isoxazolidines were prepared. Interestingly, the reaction of BnNHOH and BocNHOH with mono-sbustituted quinone monoketals gave isoxazolidine products with opposite regio-selectivity. The reductive N-O cleavage of bridged isoxazolidine gives 1,3-syn-aminoalcohols, which are backbone for a number of bioactive compounds. To demonstrate the application of this methodology, facilely functionalized aminocyclitols were synthesized in short sequence from a bridged isoxazolidine. Chapter 2 Inspired by the former discovered N,O-double Michael addition reaction, the possibility of N,N- double Michael addition reaction was explored. Under same conditions, the reaction of quinone monoketal with MeNHNHMe·2HCl did not give the desired pyrazodiline product. However, an un- expected allylic substitution of quinone monoketal was discovered. This leads to a general synthesis of o-chlorophenols from quinone monoketal under mild conditions. Various quinone monoketals were subjected to this protocol and a number of selective o-chlorination products were afforded in high yields. The mechanism of this reaction was closely examined by mixed quinone monoketals and solvent scrambling experiment. Also the relative ability of methoxyl and siloxy as leaving groups were also studied. Eventually the pyrazolidine synthesis was achieved in the presence of protic solvent. Chapter 3 The discovery of o-chlorination in chapter 2 inspired us to explore the allylic substitution of quinone imine ketals. An indole synthesis from quinone imine ketal and alkenyl ether was envisioned and explored. In the presence of catalytic amount of SnCl4 or tetra-fluoro-benzene-1,4-dicarboxylic acid, N-tosyl protected quinone imine ketals react with alkenyl ethers to give indole or indoline products. The N-acyl protected quinone imine ketals, however, react with alkenyl ethers to give preferentially 1,4-addition products. The effectiveness of this indole methodology was demonstrated in a concise synthesis of natural product Lycoranine A. Chapter 4 Phalarine is an indole alkaloid separated from the perennial grass P. coerulescens. It possesses a novel furanobisindole framework, which is a propeller-like structure. The unique structure of phalarine has interested several groups to work on the relevant synthetic studies. Specifically, Danishefsky group has reported the total synthesis of phalarine in 2007 and an asymmetric total synthesis of (-)-phalarine in 2010. Chen published a formal synthesis of (-)- and (+)-phalarine in 2011. Due to our continuing interest in indole alkaloid synthesis, a phalarine formal synthesis project was initialted. This project aims to furnish a concise biomimetic synthetic pathway to a junction compound in Danishefsky’s phalarine synthesis. Even though not finished, this project has yielded several interesting results. Chapter 4 will give a brief review of the previous synthesis of phalarine and describe our ongoing efforts in achieving a formal synthesis of phalarine

Dilatancy relation for overconsolidated clay

A distinct feature of overconsolidated (OC) clays is that their dilatancy behavior is dependent on the degree of overconsolidation. Typically, a heavily OC clay shows volume expansion, whereas a lightly OC clay exhibits volume contraction when subjected to shear. Proper characterization of the stress-dilatancy behavior proves to be important for constitutive modeling of OC clays. This paper presents a dilatancy relation in conjunction with a bounding surface or subloading surface model to simulate the behavior of OC clays. At the same stress ratio, the proposed relation can reasonably capture the relatively more dilative response for clay with a higher overconsolidation ratio (OCR). It may recover to the dilatancy relation of a modified Cam-clay (MCC) model when the soil becomes normally consolidated (NC). A demonstrative example is shown by integrating the dilatancy relation into a bounding surface model. With only three extra parameters in addition to those in the MCC model, the new model and the proposed dilatancy relation provide good predictions on the behavior of OC clay compared with experimental data

Inflating hollow nanocrystals through a repeated Kirkendall cavitation process.

The Kirkendall effect has been recently used to produce hollow nanostructures by taking advantage of the different diffusion rates of species involved in the chemical transformations of nanoscale objects. Here we demonstrate a nanoscale Kirkendall cavitation process that can transform solid palladium nanocrystals into hollow palladium nanocrystals through insertion and extraction of phosphorus. The key to success in producing monometallic hollow nanocrystals is the effective extraction of phosphorus through an oxidation reaction, which promotes the outward diffusion of phosphorus from the compound nanocrystals of palladium phosphide and consequently the inward diffusion of vacancies and their coalescence into larger voids. We further demonstrate that this Kirkendall cavitation process can be repeated a number of times to gradually inflate the hollow metal nanocrystals, producing nanoshells of increased diameters and decreased thicknesses. The resulting thin palladium nanoshells exhibit enhanced catalytic activity and high durability toward formic acid oxidation

Research on Physiological Reactions to Bath Salts Aroma

The bath salts is high-profile as its distinctive aroma makes people relaxed with fresh and energetic feelings. EEG is analyzed with the lavipeditum bath method in this study and the physiological reactions (relaxation effects) are discussed and investigated in order to provide basic data for developing the practical products that can make life more comfortable and affluent by quantification for its effect. The experiment demonstrates that the physiological reaction generated by bath salts aroma is composed of the factor of energy difference value of the mid-alpha wave of the frontal lobe in the emotion field. The analysis on energy difference value of the mid-alpha wave  that can cause physiological reaction in this experiment. In general, the aroma that induces a higher physiological reaction is the pomelo, green apple, sakura, rose, chamomile, peppermint for both sexes

Moisture content distribution model for the soil wetting body under moistube irrigation

This study investigated the moisture distribution characteristics of a soil wetting body under different influencing factors to inform the design and management of a moistube irrigation system. A mathematical model of soil moisture movement under moistube irrigation was established based on Hydrus-2D software. The suitability of the Hydrus-2D simulation model was verified by laboratory experiments. Numerical simulations were carried out with Hydrus-2D to investigate the influence of soil texture, initial moisture content, moistube specific discharge and irrigation time on the moisture distribution of a soil wetting body. The soil moisture content is highest at the moistube, and its value is related to the moistube-specific discharge and soil texture. The soil moisture content at any point in the wetting body decreased linearly with increasing distance from the wetting front to the moistube in the five set directions (vertical downward, 45° downward, horizontal, 45° upward and vertical upward). This trend is applicable to fine-textured and coarse-textured soil. An estimation model of soil moisture content including soil saturated hydraulic conductivity, initial soil moisture, the specific flow rate of the moistube and the maximum value of the wetting front distance in all directions is proposed. The model estimation is good (root mean square error = 0.008–0.018 cm3·cm−3, close to 0; Nash-Sutcliffe efficiency coefficient = 0.987, close to 1), and it can provide a practical tool for moistube irrigation design and agricultural water management

Actuator and Sensor Fault Classification for Wind Turbine Systems Based on Fast Fourier Transform and Uncorrelated Multi-Linear Principal Component Analysis Techniques

In response to the high demand of the operation reliability and predictive maintenance, health monitoring and fault diagnosis and classification have been paramount for complex industrial systems (e.g., wind turbine energy systems). In this study, data-driven fault diagnosis and fault classification strategies are addressed for wind turbine energy systems under various faulty scenarios. A novel algorithm is addressed by integrating fast Fourier transform and uncorrelated multi-linear principal component analysis techniques in order to achieve effective three-dimensional space visualization for fault diagnosis and classification under a variety of actuator and sensor faulty scenarios in 4.8 MW wind turbine benchmark systems. Moreover, comparison studies are implemented by using multi-linear principal component analysis with and without fast Fourier transform, and uncorrelated multi-linear principal component analysis with and without fast Fourier transformation data pre-processing, respectively. The effectiveness of the proposed algorithm is demonstrated and validated via the wind turbine benchmark

Synthesis and Characterization of Nanostructured WC-Co/Al Powder Prepared by Mechanical Alloying

Nanostructured WC-Co/Al powder was synthesized from WC-12Co powder and pure Al powder by mechanical alloying (MA). The morphology and microstructural evolution of WC-Co/Al powder were investigated by a series of characterization methods. The results showed that the β-Co phase in the initial WC-12Co powder was replaced by the AlxCo phases (such as Al9Co2 and Al13Co4). As the ball milling time increased, the average grain size of WC in the WC-Co/Al powder decreased firstly and then remained at a constant value of around 40 nm. The deposition behavior of powders sprayed by high velocity oxygen fuel (HVOF) spraying was investigated. During spraying, the WC-Co/Al powder had a better flattening than the WC-12Co powder without ball milling, which is beneficial to fabricate compact coatings with lower porosity

Controlling Class Layout for Deep Ordinal Classification via Constrained Proxies Learning

For deep ordinal classification, learning a well-structured feature space specific to ordinal classification is helpful to properly capture the ordinal nature among classes. Intuitively, when Euclidean distance metric is used, an ideal ordinal layout in feature space would be that the sample clusters are arranged in class order along a straight line in space. However, enforcing samples to conform to a specific layout in the feature space is a challenging problem. To address this problem, in this paper, we propose a novel Constrained Proxies Learning (CPL) method, which can learn a proxy for each ordinal class and then adjusts the global layout of classes by constraining these proxies. Specifically, we propose two kinds of strategies: hard layout constraint and soft layout constraint. The hard layout constraint is realized by directly controlling the generation of proxies to force them to be placed in a strict linear layout or semicircular layout (i.e., two instantiations of strict ordinal layout). The soft layout constraint is realized by constraining that the proxy layout should always produce unimodal proxy-to-proxies similarity distribution for each proxy (i.e., to be a relaxed ordinal layout). Experiments show that the proposed CPL method outperforms previous deep ordinal classification methods under the same setting of feature extractor.Comment: Accepted by AAAI 202