Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Analytical Chemistry (6)
- Engineering (6)
- Chemical Engineering (3)
- Life Sciences (3)
- Physical Chemistry (3)
-
- Polymer Chemistry (3)
- Biochemistry (2)
- Biochemistry, Biophysics, and Structural Biology (2)
- Materials Science and Engineering (2)
- Organic Chemistry (2)
- Agriculture (1)
- Atmospheric Sciences (1)
- Civil Engineering (1)
- Civil and Environmental Engineering (1)
- Inorganic Chemistry (1)
- Molecular Biology (1)
- Nanoscience and Nanotechnology (1)
- Oceanography and Atmospheric Sciences and Meteorology (1)
- Plant Sciences (1)
- Institution
Articles 1 - 19 of 19
Full-Text Articles in Chemistry
New Strategies To Reveal Protein Candidates In Protein-Protein Interactome Study, Meng-Chieh Chen
New Strategies To Reveal Protein Candidates In Protein-Protein Interactome Study, Meng-Chieh Chen
Open Access Theses
Comprehensive protein-protein interaction network analysis can help reveal protein functions in a system-wide manner. A reliable knowledgebase of interaction networks is not only important for selecting the candidates for drug therapies, but also for evaluating the disease risk. In current interaction databases, 322579 interactions comprised of 56460 proteins have been reported (statistical analysis from APID: Agile Protein Interaction DataAnalyzer; http://bioinfow.dep.usal.es/apid/index.htm). The huge datasets are contributed mainly by yeast -two -hybrid (Y2H) screening and affinity-purification followed by mass spectrometry (AP-MS). High false positive rates and failing to cover certain interaction categories are the limitations of these two methods. Here, we developed …
High-Purity Gallium Analysis By Inductively Coupled Plasma Mass Spectrometry, Kyungjean Min
High-Purity Gallium Analysis By Inductively Coupled Plasma Mass Spectrometry, Kyungjean Min
Open Access Theses
The mobility of Two-dimensional Electron Gas in AlGaAs/GaAs heterostructures that are grown in the Molecular Beam Epitaxy (MBE) can be increased by purification of the gallium used to grow the films. To attain 200 million cm2/Vs mobility, the impurity concentration of gallium should be reduced to below 1 ppb. The commercial 7N (99.99999%) gallium with 100 ppb total impurity is currently used in the MBE at Purdue University and is being purified by zone refining. To evaluate the commercial 7N gallium and establish the methodology for the impurity measurement after zone refining, germanium, iron, and zinc in 6N and 7N …
Elucidating The Mechanism Of Phenylpropanoid Regulation By The Arabidopsis Mediator Complex, Wenjie Zeng
Elucidating The Mechanism Of Phenylpropanoid Regulation By The Arabidopsis Mediator Complex, Wenjie Zeng
Open Access Theses
The Mediator complex is a multi-protein co-regulator of eukaryotic transcription which plays a role in the expression of many, if not most, genes of the cell. Two Mediator subunits, REF4 and RFR1, were demonstrated to be important for the normal regulation of phenylpropanoid metabolism in Arabidopsis. Phenylpropanoids are a family of specialized plant metabolites derived from the amino acid phenylalanine and are involved in defense against pathogens, UV protection and structural support. In order to understand how Mediator regulates phenylpropanoid metabolism through REF4 and RFR1, a better basic understanding of this protein complex is required. Here I provide data on …
Reverse-Phase Liquid Chromatography Of Small Molecules Using Silica Colloidal Crystals, Natalya Khanina
Reverse-Phase Liquid Chromatography Of Small Molecules Using Silica Colloidal Crystals, Natalya Khanina
Open Access Theses
Capillaries packed with a silica colloidal crystal (SCC) of 470 nm nonporous particles have recently been shown to offer significant improvements in the peak width, resolution, and speed of protein analysis due to the reduction of the A and C term broadening contributions of the Van Deemter equation. While protein separations using this technology have shown vast improvements, small molecules remain largely unexplored. As the SCC allows for an approximately diffusion limited system, extremely high plate numbers are expected for small molecule separations. The research presented herein studies the feasibility of pressure-driven small molecule separation using SCCs and commercial instrumentation. …
Identifying Conditions To Optimize Lactic Acid Production From Food Waste, Raymond M. Redcorn
Identifying Conditions To Optimize Lactic Acid Production From Food Waste, Raymond M. Redcorn
Open Access Theses
There is an increased demand for lactic acid for the production of biopolymers and to aid nutrient removal in wastewater treatment. Food waste offers a source of soluble sugars to produce lactic acid, which does not increase land demand, but digestion conditions have yet to be optimized when co-digested with primary sludge. Food waste was collected from cafeteria waste bins, homogenized and seeded with primary sludge. A Box Behnken Response surface design was used to optimize lactic acid production based on pH, temperature, loading rate, and retention time. Subsequent experiments verified and refined those conditions to optimize for both yield …
Impact Of Nanostructure On Polymer-Based Nonvolatile Memory Devices, Seung Hyun Sung
Impact Of Nanostructure On Polymer-Based Nonvolatile Memory Devices, Seung Hyun Sung
Open Access Theses
Memory functionality is essential for many high-end electronic applications (e.g. , smart phones, personal computers). Particularly, organic nonvolatile memory devices based on polymer ferroelectric materials are a promising approach toward the development of low-cost memory due to the ease of processing and flexibility associated with the device. Here, we will focus on a memory device with a two-component active layer and a diode structure. This ferroelectric diode (FeD) has a nanostructured active layer, composed of ferroelectric and semiconducting polymers, and it can provide easy access to high-performance polymer-based memory devices. In order to create these nanostructured active layers, we …
Resonant Two-Photon Ionization Studies Of Non Covalent Interactions In Halo Aromatic Clusters And Spin-Orbit Coupling Modeling In Mono-Halocarbenes, Silver Nyambo
Dissertations (1934 -)
Non-covalent interactions in halobenzenes (PhX) (X=F, Cl, Br) and phenylamine (C6 H5 NH2 ) have been studied here using resonance two-photon ionization (R2PI) spectroscopy combined with a linear TOF-mass spectrometer. Their interaction with polar molecules in form of ammonia (NH 3 ) and trifluorohalomethanes (CF3 X) has also been studied. DFT and TD-DFT calculations using M06-2X functionals were carried out on different cluster conformations to compliment experimental results. A general trend of broadness in homogenous dimers (PhX)2 , has been attributed to mainly the presence of multiple cluster isomers and Frank-Condon activity in the low …
Gas-Phase Ion/Ion Reactions Of Biomolecules: An Examination Of Carboxylate Reactivity And Arginine Based Non-Covalent Complexes, Nathan Zachary Barefoot
Gas-Phase Ion/Ion Reactions Of Biomolecules: An Examination Of Carboxylate Reactivity And Arginine Based Non-Covalent Complexes, Nathan Zachary Barefoot
Open Access Theses
The advent of Electrospray Ionization with the ability to generate multiply charges ions has contributed significantly to the study of gas-phase ion/ion reactions. With the tools available in mass spectrometry it has been shown that these reactions are effective at transforming one type of gaseous ion into another through a series of reactions. This work examines some of these reactions and their application to field of proteomics specifically focusing on the amino acids of arginine and lysine. NHS reagents have been shown to react to both of these molecules with in the gas-phase under different conditions but have relies on …
Correlating Molecular Architecture Of A Radical Polymer Based Copolymer With Its Electrical Transport Properties, Holly Chan
Open Access Theses
The design and synthesis of electrically-conductive macromolecules can lead to significant improvements in the performance of polymer-based energy conversion devices (e.g., thermoelectric devices). For these organic electronic devices, conjugated polymers have dominated the area of conductive polymers; however, these materials are usually synthesized using conditions that lead to poorly-defined polymers. Furthermore, in these increasingly-standard polymers, the charge transport ability of the polymer thin films is largely affected by the degree of crystallinity, which is a difficult property to control in a reproducible fashion. Therefore, we seek to explore a new class of amorphous, non-conjugated polymers containing a stable radical …
Separation Of On-Column Labeled Model Proteins With Packed Capillary Electrophoresis, Yingxu Hao
Separation Of On-Column Labeled Model Proteins With Packed Capillary Electrophoresis, Yingxu Hao
Open Access Theses
Protein drugs are increasingly developed in the pharmaceutical company. Under the regulation of FDA, high purity of therapeutic proteins needs to be maintained. Before putting those drugs in the market, fast and efficient method is in need to achieve homogeneity. Traditionally, polyacrylamide gel electrophoresis (PAGE), capillary electrophoresis (CE), and size-exclusion chromatography (SEC) are used for the purification process. These methods have the disadvantages of low time and cost efficiency, and this quality assurance process has become the bottleneck of production. In our group, sub-micron silica colloidal particles with polyacrylamide layer on the surface are packed inside capillaries to increase the …
A Screening Platform For Identification Of Compounds That Inhibit Protein Synthesis In Pseudomonas Aeruginosa, Yanmei Hu
Theses and Dissertations - UTB/UTPA
Pseudomonas aeruginosa is a Gram-negative pathogenic bacteria and a common cause of nosocomial infections. This pathogen has recently garnered attention due to its pan-resistance. We have developed a poly(U) mRNA-directed aminoacylation/translation (A/T) protein synthesis system from P. aeruginosa. The concentration of each component of the system has been arrived at through multiple rounds of optimization. Poly-phenylalanine synthesis in the system was monitored using scintillation proximity assays (SPA). This system has been used to screen two natural compound libraries (>1100) and a number of the compounds that inhibit greater than 50% of the activity of the system have been identified. …
Metal Oxide Nanostructures For Energy Conversion And Storage, Xing Sun
Metal Oxide Nanostructures For Energy Conversion And Storage, Xing Sun
Theses and Dissertations - UTB/UTPA
With the depletion of non-renewable resources and the related problems such as environmental pollutions and global warming effect, the society urgently needs more efficient and controllable energy conversion and storage systems. Three-dimensional ZnO nanoforests were prepared and morphology-tunable, which benefits both of energy conversion and storage systems. Willow-like ZnO nanoforests led the highest conversion efficiency of photoelectrochemical water splitting in reported pure ZnO nanostructures. Compared with nanowire arrays, ZnO@MnO2 nanoforests delivered 5 times higher specific capacitances within the same footprint area. V2O5@PPy exhibited higher specific capacitance and better rate stability than pure V2O5 nanofibers. This work lays the foundation for …
Monitoring Citrus Nutrition In The Rio Grande Valley For Fertilizer Recommendations, Iram Lopez
Monitoring Citrus Nutrition In The Rio Grande Valley For Fertilizer Recommendations, Iram Lopez
Theses and Dissertations - UTB/UTPA
Soil fertility and plant nutrition is crucial for a better yield and consistent harvest in the Rio Grande Valley for local farmers growing citrus trees. A field of oranges and a field of grapefruits were monitored and nutrition deficiencies were noticed that played an important role during fruit set. Soil samples that were taken throughout the year were analyzed via a carbon dioxide extraction method that mimics the way plants naturally take up nutrients or extract nutrients from every soil type. Macronutrients such as the N, P, K, Na, Ca, Mg and some of the micronutrients (Zn, Fe, Mn, and …
Cloning And Characterization Of Ef-Tu And Ef-Ts From Streptococcus Pneumoniae, Carlos Eduardo Rivera
Cloning And Characterization Of Ef-Tu And Ef-Ts From Streptococcus Pneumoniae, Carlos Eduardo Rivera
Theses and Dissertations - UTB/UTPA
Antibiotic resistance is a prevalent threat to public health around the world, and resistance among strains of Streptococcus pneumoniae is growing rapidly. This increasing resistance elevates the demand for new drug discoveries. This research attempts to develop a means to combat S. pneumoniae by targeting protein synthesis for the discovery of new antibacterial agents. Protein synthesis components, elongation factor Tu (EF-Tu) and elongation factor Ts (EF-Ts) facilitate many steps in the biosynthesis of proteins and are therefore essential proteins involved in protein synthesis. EF-Tu and EF-Ts were cloned, expressed, purified, and enzymatically characterized to help develop a screening system that …
The Development Of 6.7% Efficient Copper Zinc Indium Selenide Devices From Copper Zinc Indium Sulfide Nanocrystal Inks, Brian Kemp Graeser
The Development Of 6.7% Efficient Copper Zinc Indium Selenide Devices From Copper Zinc Indium Sulfide Nanocrystal Inks, Brian Kemp Graeser
Open Access Theses
As solar cell absorber materials, alloys of CuIn(S,Se)2 and Zn(S,Se) provide an opportunity to reduce the usage of indium along with the ability to tune the band gap. Here we report successful synthesis of alloyed (CuInS2 )0.5(ZnS)0.5 nanocrystals by a method that solely uses oleylamine as the liquid medium for synthesis. The reactive sintering of a thin film of these nanocrystals via selenization at 500 °C results in a uniform composition alloy (CuIn(S,Se)2 )0.5 (Zn(S,Se)) 0.5 layer with micron size grains. Due to the large amount of zinc in the film, the sintered grains exhibit the zinc blende structure instead …
Investigation Of Isotope Effects Of Ozone As A Function Of Temperature, Daniel J. Mcmahon
Investigation Of Isotope Effects Of Ozone As A Function Of Temperature, Daniel J. Mcmahon
Open Access Theses
Ozone is an important oxidizer in the atmosphere and plays a crucial role as a cleanser, removing various compounds such NOx and SOx. It also is intriguing to those that study stable isotopes as it has a unique signature found in no other oxygen containing molecule. Ozone is observed to fractionate mass independently, which means it does not follow the typical δ 17 O /δ18 O = 0.52 ratio expected for molecules enriched with 17 O and 18 O. The magnitude of ozone's mass independent enrichment has been studied in laboratory experiments and atmospheric observations but its explanation is still …
Applications Of Calculated Second Harmonic Generation Tensors On Monomolecular And Bimolecular Systems, Gregory R. Snyder
Applications Of Calculated Second Harmonic Generation Tensors On Monomolecular And Bimolecular Systems, Gregory R. Snyder
Open Access Theses
The field of nonlinear optics (NLO) has proven itself as a relatively recent and powerful area of science in the areas of microscopy and high-sensitivity quantification measurements. In particular, symmetry selective NLO processes such as second harmonic generation (SHG) take advantage of symmetry rules to cancel background noise almost completely, leading to both high resolution images and limits of detection (LOD) in the photon counting range. Background noise in SHG is negated as result of signal cancellation in systems containing inversion symmetry; generally isotropic sources. Quantum mechanical computational chemistry has enriched the field of NLO by enabling studies on hypothetical …
Effect Of Multivalent Ions On The Swelling And Mechanical Behavior Of Superabsorbent Polymers (Saps) For Mitigation Of Mortar Autogenous Shrinkage, Qian Zhu
Open Access Theses
The chemical and physical structure-property relationships of model superabsorbent polymer (SAP) hydrogels were characterized with respect to swelling behavior and mechanical properties in different ionic solutions (Na+ , Ca2+ , and Al3+ ). The model hydrogels were composed of poly(sodium acrylate-acrylamide) (PANa-PAM) copolymer with varying concentrations of PANa (0, 17, 33, 67, and 83 wt.%) and covalent crosslinking densities of 1, 1.5, and 2 wt.%. By synthesizing the hydrogels in-house, systems with independently tunable amounts of covalent crosslinking and anionic functional groups were created, allowing for the relative effects of covalent and ionic crosslinking on the properties of the hydrogels …
Protein Affinity Extraction Of Prostate Specific Antigen (Psa) Using Submicron Spheres, Yao Wang
Protein Affinity Extraction Of Prostate Specific Antigen (Psa) Using Submicron Spheres, Yao Wang
Open Access Theses
PSA has been used as a biomarker for prostate cancer for a long time. To characterize different glycoforms of PSA using techniques like UHPLC and cIEF, concentration and purification of PSA from complex samples becomes necessary. Our group has developed submicron silica spheres based affinity beads to extract PSA through immunoprecipitation. This study focuses on measuring the bead performance when antibody type/amount was varied and PSA concentration was lowered for clinical use. To better satisfy the requirement of large-scale extraction, several attempts were made to increase the bead capacity. The results will be presented and future directions of the project …