Design of nanostructured photocatalysts for hydrogen production and environmental application

Tableau d'honneur de la Faculté des études supérieures et postdorales, 2014-2015Au cours des dernières décennies, la photocatalyse par les semiconducteurs a été intensivement étudiée pour une grande variété d'applications, y compris la production d'hydrogène à partir de la dissociation de l'eau et la décomposition des polluants dans l'air et l'eau. Actuellement, TiO2 est le matériau photocatalytique le plus largement étudié en raison de son faible coût et ses propriétés physiques et chimiques exceptionnelles. Cependant, la rapide recombinaison électron-trou et son absorption dans la région de l’ultra-violet le rendent inefficace sous la lumière du soleil. Cette thèse vise à développer des photocatalyseurs efficaces à base de TiO2 en appliquant différentes stratégies telles que le contrôle de la morphologie des nanoparticules de TiO2, le couplage du TiO2 avec des métaux et d’autres semi-conducteurs, et l'optimisation de la porosité des photocatalyseurs. Nous avons mis au point une méthode de synthèse solvo-thermique pour produire des nanocristaux de TiO2 hautement cristallins de différentes formes, tel que rhombique, sphérique, et sous forme de tige. Les nanocristaux TiO2 obtenus ont ensuite été décorés par des clusters d'Ag de taille contrôlée pour former des hybrides Ag-TiO2 ayant une performance photocatalytique supérieure à celle du photocatalyseur conventionnel Ag-TiO2-P25. Nous avons également développé une technique non-hydrolytique pour la synthèse de nanodisques uniformes de TiO2 de diamètre contrôlé entre de 12 nm et 35 nm. Ces nanodisques ont ensuite été utilisés comme blocs de construction pour la synthèse des photocatalyseurs multi-composants solubles dans l'eau à base de CdS-Titanate-Ni; ces derniers sont très actifs pour la production d'hydrogène grâce à leur absorption efficace de lumière visible et leur séparation efficace d’électrons et trous. Finalement, nous avons construit un assemblage tridimensionnel ordonné de nanosphères creuses de coquille mince de Au/TiO2, en utilisant les blocs de construction de nanodiques de titanate. Ces photocatalyseurs présentent non seulement une surface spécifique très élevée, mais aussi un comportement photonique et une diffusion multiple de la lumière, ce qui améliore significativement l'absorption de la lumière visible. Ces nanosphères creuses de structure ordonnée tridimensionnelle présentent une activité photocatalytique induite par la lumière visible, étant plusieurs fois plus élevée que celle des nanopoudres conventionnelles d’Au/TiO2.Semiconductor photocatalysis has been intensively studied over the past decades for a wide variety of applications including hydrogen production from water splitting and decomposition of pollutants in air and water. Currently, TiO2 is the most widely investigated photocatalytic material because of its low cost and outstanding physical and chemical properties. However, its fast electron-hole recombination and light absorption only in ultra-violet region make it inefficient working under sunlight. The goal of the research presented in this thesis is to design efficient TiO2 based photocatalysts by applying various strategies encompassing controlling the morphology of TiO2 particles, coupling TiO2 with metals, and other semiconductors and optimizing porosity of the photocatalysts. We have developed a solvothermal synthetic method for producing highly crystalline TiO2 nanocrystals with various shapes, such as rhombic, spherical, and bar. The obtained TiO2 nanocrystals were then decorated with size-controlled Ag clusters to form Ag-TiO2 hybrids which exhibit superior photocatalytic performance in comparison to conventional Ag-TiO2-P25 photocatalyst. We have also developed a nonhydrolytic technique for the synthesis of uniform titanate nanodisks with controlled diameter in the range of 12 nm to 35 nm. These nanodisks were then used as building blocks for the design of water-soluble CdS–Titanate–Ni multicomponent photocatalysts which are highly active for hydrogen generation due to their effective visible light absorption and efficient charge separation. Finally, we have constructed a three-dimensional ordered assembly of thin-shell Au/TiO2 hollow nanospheres from titanate nanodisk building blocks. The designed photocatalysts exhibit not only a very high specific surface area but also photonic behavior and multiple light scattering, which significantly enhances visible light absorption. As a result, Au/TiO2 hollow nanospheres with three-dimensional ordered structure exhibit a visible-light-driven photocatalytic activity that is several times higher than conventional Au/TiO2 nanopowders

Seed protein, oil, and yield of soybean genotypes with high and normal oleic acid concentration

July 2013.A Thesis Presented to the Faculty of the Graduate School at the University of Missouri--Columbia In Partial Fulfillment of the Requirements for the Degree Master of Science.Thesis supervisor: Dr. J. Grover Shannon.Soybeans with seed oil high in oleic acid content have been developed and are desired by oil processors because of improved oxidative stability for broader use in food, fuel and other products. Conventional soybean lines with 80% oleic acid content were generated by combining two mutant genes, mutant S117N FAD2-1A allele from 17D and mutant P137R FAD2-1B allele from PI283327. Thirty five F4:7 high oleic lines with these mutant FAD2-1A and FAD2-1B genes were compared to thirty five F4:7 normal or wild type oleic acid lines for seed contents of the five fatty acids common to soybean, total oil content, total protein content, and seed yield from five crosses grown in six environments. The high oleic genotypes averaged >75% oleic acid content and concentrations of palmitic and linolenic acids were significantly lower (30% lower) than their normal oleic acid counterparts in each environment. When averaged across all locations and populations, seed yield of the high oleic lines were within 2% of the normal oleic lines. Because of the negative correlation of protein with oil content and seed yield shown in many other studies, it was surprising that these high oleic lines averaged significantly higher in protein and oil with similar yield compared to normal oleic lines. These results provided evidence that high oleic soybeans can have comparable yields with the potential to generate more oil with greater functionality and higher protein meal for improved feed and food value compared to soybeans with normal oleic acid content from the same cross.Includes bibliographical references (pages 26-30)

A Low-cost Depth Imaging Mobile Platform for Canola Phenotyping

To meet the high demand for supporting and accelerating progress in the breeding of novel traits, plant scientists and breeders have to measure a large number of plants and their characteristics accurately. A variety of imaging methodologies are being deployed to acquire data for quantitative studies of complex traits. When applied to a large number of plants such as canola plants, however, a complete three-dimensional (3D) model is time-consuming and expensive for high-throughput phenotyping with an enormous amount of data. In some contexts, a full rebuild of entire plants may not be necessary. In recent years, many 3D plan phenotyping techniques with high cost and large-scale facilities have been introduced to extract plant phenotypic traits, but these applications may be affected by limited research budgets and cross environments. This thesis proposed a low-cost depth and high-throughput phenotyping mobile platform to measure canola plant traits in cross environments. Methods included detecting and counting canola branches and seedpods, monitoring canola growth stages, and fusing color images to improve images resolution and achieve higher accuracy. Canola plant traits were examined in both controlled environment and field scenarios. These methodologies were enhanced by different imaging techniques. Results revealed that this phenotyping mobile platform can be used to investigate canola plant traits in cross environments with high accuracy. The results also show that algorithms for counting canola branches and seedpods enable crop researchers to analyze the relationship between canola genotypes and phenotypes and estimate crop yields. In addition to counting algorithms, fusing techniques can be helpful for plant breeders with more comfortable access plant characteristics by improving the definition and resolution of color images. These findings add value to the automation, low-cost depth and high-throughput phenotyping for canola plants. These findings also contribute a novel multi-focus image fusion that exhibits a competitive performance with outperforms some other state-of-the-art methods based on the visual saliency maps and gradient domain fast guided filter. This proposed platform and counting algorithms can be applied to not only canola plants but also other closely related species. The proposed fusing technique can be extended to other fields, such as remote sensing and medical image fusion

Characterization of a diverse USDA collection of wild soybean (glycine soja siebold & zucc.) accessions and subsequent mapping for seed composition and agronomic traits in a RIL population

Dr. Andrew Scaboo, Dissertation Supervisor.Includes vita.Field of study: Plant insect and microbial sciences."July 2018."The relatively low genomic variation of current U.S. soybean [Glycine max (L.) Merill] cultivars constrains the improvement of grain yield, seed quality, and other agronomic traits within soybean breeding programs. Recently, a substantial effort has been undertaken to introduce novel genetic diversity present in wild soybean (Glycine soja Siebold & Zucc.) into new elite cultivars, in both public and private applied soybean breeding programs. The objectives of this research were to evaluate the phenotypic diversity within a core collection of 80 G. soja plant introductions (PIs) in the United States Department of Agriculture National Genetic Resources Program that were collected in China, Japan, Russia, and South Korea, and to analyze the correlations between agronomic and seed composition traits. Field tests were conducted in Missouri and North Carolina during three years, 2013, 2014, and 2015, in a randomized complete block design (n=3). The phenotypic data collected included plant maturity date, seed weight, and the seed concentration of protein, oil, essential amino acid, fatty acid, and soluble carbohydrates. Analyzing the data from six environments, we found genotype was a significant (p < 0.0001) source of variation for maturity date, seed weight, seed protein and amino acids, seed oil and fatty acids, and seed carbohydrates. Significant correlations were observed between numerous traits. The core collection had lower seed weight, higher seed content of protein, linolenic acid, raffinose and stachyose but lower seed content of oil and oleic acid than those of the cultivated soybean lines that were used as checks. The amino acid profile of the core collection was significantly different from that of the checks. An association analysis revealed 19 SNP that were significantly associated with maturity, seed weight, and seed contents of aspartic acid, glutamine, palmitic acid, oleic acid, and linoleic acid. The information and data collected in this study will be invaluable in guiding soybean breeders and geneticists in selecting promising Glycine soja plant introductions for research and cultivar improvement. In addition the identification of quantitative trait loci (QTLs) associated with the contents of seed protein and oil, maturity, branching traits, height, lodging, and yield in a recombinant inbred line (RIL) population developed from one single F2 plant from the cross between Osage and PI593983 was carried out. The mapping population in this study included 164 F4:6 recombinant inbred lines (RILs) derived from a cross between Osage, a cultivated soybean variety, and PI593983, a wild soybean accession. Field tests were carried out in Missouri for two years during 2016 and 2017, in a randomized complete block design (n=2). Both protein and oil contents showed high heritabilities. Seed protein and seed oil were negatively correlated (-0.77). A total of 4,374 polymorphic markers were used to construct a genetic linkage map, and nine QTLs for protein content, explained 7.6 to 36.7% of variance, and seven QTLs for oil content, explained for 7.8 to 29.7% of variance, were detected using composite interval mapping. addition we identified eight novel QTLs and confirmed sixteen QTLs associated with maturity (R2 = 6.4 to 26.3%), plant height (R2 = 7.4 to 15.5%), and total branch length (R2 = 9.3% and 14.5%) in individual and across environments, and the ratio of total branch length to plant height (R2 = 11.8%), yield (R2 =12.8 and 15.7), and lodging (R2 = 12.1 and 13.4) in individual studied environments. Sixteen QTLs for maturity, yield, and plant height confirmed previously reported QTLs, and eight QTLs have not been reported before. The results of this study will facilitate the identification of the causative genes for seed protein and oil, maturity, height, lodging, and branching traits, and will help soybean breeder improve soybean performance by developing markers for marker-assisted selection.Includes bibliographical references

Performance analysis of global local mean square error criterion of stochastic linearization for nonlinear oscillator

The paper presents a performance analysis of global-local mean square error criterion of stochastic linearization for some nonlinear oscillators. This criterion of stochastic linearization for nonlinear oscillators bases on dual conception to the local mean square error criterion (LOMSEC). The algorithm is generally built to multi-degree of freedom (MDOF) nonlinear oscillators. Then, the performance analysis is carried out for two applications which comprise a rolling ship oscillation and two-degree of freedom one. The improvement on accuracy of the proposed criterion has been shown in comparison with the conventional Gaussian equivalent linearization (GEL)

Serial bus adapter design for FPGA

In recent years, FPGAs (Field Programmable Gate Arrays) have become a popular platform for testing and implementing hardware designs by increasing their capacity and cost efficiency in the competition with Application Specific Integrated Circuits (ASICs). Processors can be used for any problem but they have not been optimized for specific problems. The design of ASIC is an extremely complex task, very time consuming and expensive; they are used for mass products. FPGA is an intermediate solution between general purpose processors and ASICs. Altera Cyclone V 28nm is a System On Chip (SoC), which integrates a Hard Processor Core (HPS), peripherals, and memory controller with the FPGA fabric. However, HPS consist of only one-directional serial data (SDA) buses and serial clock (SCL) buses and provides support for a communication link only between integrated circuits on a board. It is necessary to build an I2C serial bus adapter in order to communicate between HPS and other devices outside the board. I2C serial bus adapter is implemented and tested in this thesis. It adapts the communication from one-directional serial data line of hard processor system to bi-directional data line. In order to test the I2C adapter in both writing data operation and reading data operation, Signal Generator blocks to generate testing signals are implemented and I2C Slave block from OpenCores to detect and display data to LEDs is used. All the blocks are implemented in VHSIC Hardware Description Language (VHDL). The verifications for I2C Adapter, Signal Generator and I2C Slave are inspected by waveforms on Modelsim SE 10.2c simulator. The block implementations are compiled and programmed by Quartus II 13.1 to DE1-SoC FPGA development board. DE1-SoC board buttons and LEDs are used to test the I2C adapter operation by a user. The results show that the adapter works as specified

Patient satisfaction with health care services at a National Institute of Ophthalmology

Little is known about how patients in developing countries, such as Vietnam, are satisfied with eye care services. The purpose of this study was to assess the satisfaction with health services and its associated factors among patients attending a national institute of ophthalmology in Vietnam. In a cross-sectional study utilizing quantitative methods, 500 inpatients and their relatives attending a national institute of ophthalmology in Vietnam were approached for data collection. The results indicated that under 50% of the patients were satisfied with eye care services. However, when classified by level of satisfaction, only 6.8% were very satisfied with all domains of care. There was no significant difference in satisfaction by gender and income, while significant differences by department, residence, and education were found. Patients who were from rural areas, were better educated, and used the services of the glaucoma department, were more satisfied with eye care than those from urban areas, were less educated, and used the services of treatment-on-demand department. Multivariable regression detected 2 main factors, gender and location, associated with patient satisfaction. Patients who were female and came from rural and remote areas were more likely to be satisfied than patients who were male and living in urban areas. The study suggests that to continue to improve health care quality, it is important to eliminate differences in providing eye care services regardless of whether patients are male or female, and whether they come from a rural or urban area. Copyright © 2017 John Wiley & Sons, Ltd

Comparing Labor Productivity of Vietnam to Some Asian Countries

In Vietnam, social labor productivity is an indicator of the National Statistical Indicator System (specified in the Law on Statistics), which is calculated by the average GDP per employed worker per year. Research results show that in the 2016-2020 period, labor productivity of the whole economy has improved markedly, with an average increase of 5.78%/year in the 2016-2020 period. However, Vietnam’s labor productivity still has internal limitations that have not been overcome. In comparison with selected Asian countries, Vietnam’s labor productivity has a low absolute value despite its relatively high growth since 1991. In most of the sectors compared, it is basically at the lowest level. As a result, proposing solutions to improve and enhance labor productivity aimed at promoting sustainable economic growth in Vietnam in the coming time is an urgent issue for the development of the country

The roles of, activities of, and competencies for, community nursing services in rural Vietnam: Implications for policy decisions

Community health workforce plays a vital role in providing primary health care services as per the needs of residents; however, few studies have examined how nurses work within commune health centers (CHCs). Using qualitative methods including interviews and focus group discussions with key stakeholders, this study explores the roles, activities, and competencies required of community nursing services in rural districts within Vietnam. Two primary roles were identified: CHC nursing and family nursing. For the latter, in addition to providing people with general health care and health communication, they were expected to also deliver psychological care. CHC nursing fulfilled more roles and required four specific competencies: clinical care, communication, management, and planning/coordination activities. Despite these various roles serving people within a community, few ongoing efforts at either the local or national level are aimed at supporting these nurses. The study highlights the need for policy decisions via either developing a new job position policy or adapting the existing policy by integrating new roles into the existing positions of CHC nurses in Vietnam. © 2018 John Wiley & Sons, Ltd. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Nguyen Huy" is provided in this record*