Miracle-dz/UniFAR-FTUs huggingface dataset:
Styrene and Methyl Methacrylate Random Copolymerization via AGET ATRP: Incorporation of Hydrophobic Silica Aerogel Nanoparticles

Hexamethyldisilazane-modified silica aerogel nanoparticles were used for in situ copolymerization of styrene and methyl methacrylate via activators generated by electron transfer atom transfer radical polymerization (AGET ATRP) to synthesize well-defined random poly(styrene-co-methyl methacrylate) nanocomposites. Unique characteristics of the synthesized hydrophobic silica aerogel nanoparticles were evaluated by FTIR, thermogravimetric analysis (TGA), nitrogen adsorption/desorption isotherm, SEM, and TEM. Conversion and molecular weight determinations were carried out using gas and size exclusion chromatography, respectively. Adding of hydrophobic silica aerogel nanoparticles by 3 wt% results in a decrease of conversion from 92 to 76%. In addition, molecular weight of the copolymer chains decreases from 39,147 to 33,092 g⋅mol−1; however, the polydispersity index increases from 1.51 to 2.03. Copolymers composition was evaluated using 1H NMR spectroscopy. Increasing thermal stability of the nanocomposites is demonstrated by TGA. Differential scanning calorimetry shows a decrease in glass transition temperature from 69.1 to 59.3°C by addition of 3 wt% hydrophobic silica aerogel nanoparticles.
Materials research for passive solar systems: solid-state phase-change materials

A set of solid-state phase-change materials is being evaluated for possible use in passive solar thermal energy storage systems. The most promising materials are organic solid solutions of pentaerythritol (C/sub 5/H/sub 12/O/sub 4/), pentaglycerinve (C/sub 5/H/sub 12/O/sub 3/), and neopentyl glycol (C/sub 5/H/sub 12/O/sub 2/). Solid solution mixtures of these compounds can be tailored so that they exhibit solid-to-solid phase transformations at any desired temperature betweeen 25/sup 0/C and 188/sup 0/C, and have latent heats of transformation between 20 and 70 cal/g. Transformation temperatures, specific heats, and latent heats of transformation have been measured for a number of these materials. Limited cyclic experiments suggest that the solid solutions are stable. These phase-change materials exhibit large amounts of undercooling; however, the addition of certain nucleating agents as particulate dispersions in the solid phase-change material greatly reduces this effect. Computer simulations suggest that the use of an optimized solid-state phase-change material in a Trombe wall could provide better performance than a concrete Trombe wall four times thicker and nine times heavier. Nevertheless, a higher cost of the phase-change materials (approx. =$0.70 per pound) is likely to limit their applicability in passive solar systems unless their performance can be significantly improved through furthermore » research. « less
Production of silk fibroin nanoparticles using ionic liquids and high‐power ultrasounds

Biopolymeric nanoparticles have attracted great research interest in the last few years due to their multiple applications. This article describes how high-power ultrasounds are capable of enhancing the dissolution process of silk proteins in ionic liquids (ILs) and how silk fibroin nanoparticles (SFNs) can be obtained directly from the silk/ionic liquid solution (SIL) by rapid desolvation in polar organic solvents. The silk fibroin integrity is highly preserved during the dissolution process, as confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the SIL. These regenerated SFNs are insoluble in water and other common organic solvents and are indistinguishable from the classical SFNs with respect to their diameter (180 ± 5 nm), Zeta potential (−25 ± 3 mV), high degree of β-sheet and low cytotoxicity. Large amounts of silk can be turned into biomaterials directly from the SIL solution for use in a wide range of applications, while the ILs can be recovered from the coagulant solution under reduced pressure and reused without loss of their solvent properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41702.
Synthesis and Electrochemical Studies of LiMnO2 Prepared at Low Temperatures

A new form of LiMnO{sub 2}, which has recently been shown to reversibly intercalate lithium, has many advantages over other popular lithium-ion battery cathode materials. The authors describe improvements in the previously reported low temperature (300--450 C) synthesis and report a new synthesis route based on ion exchange which takes place at 100 C. Electrochemical performance is shown to be strongly dependent on synthesis temperature. In situ x-ray diffraction and long time cycling measurements indicate that an irreversible structural transformation to disordered spinel takes place when Li is removed from LiMnO{sub 2}. Nevertheless, the specific capacity of this material is over 190 mAh/g between 2.5 and 4.2 V.
Chemical Composition and Antimicrobial Activities of the Essential Oil from Glycyrrhiza glabra Leaves

Abstract The essential oil of Glycyrrhiza glabra leaves was obtained by hydrodistillation and analyzed by GC and GC-MS. Other parameters such as refractive index, optical rotation; density, polarimetric deviation; freezing point and Solubility in ethanol are also measured. The main hydrocarbon and oxygen containing compounds were: Isoniazid (13.36 %) ; Diethyltoluamide (6.56 %), Benzoic acid (5.37 %), Benzene (4.58 %), Linalool (2.25 %), Prasterone (5.63 %), Warfarin (1.43 %), Iodoquinol (1.90 %), Phenol, 4-(2-aminopropyl) (1.30 %). The screening of antibacterial activity was conducted by a disc diffusion test and the minimum inhibitory concentration was determined against Pseudomonas Aeruginosa, Salmonella typhi, Escherichia coli and Staphylococcus aureus.
BOUNDED BEAM REFLECTION AND TRANSMISSION EFFECTS IN TERMS OF COMPLEX HARMONIC WAVES

Surface waves, which are locally a combination of inhomogeneous waves, are found as an immediate consequence of the bounded beam representation in terms of complex harmonic waves. Decay and velocity of these waves can be obtained directly from the separation of the reflected field into an attendant reflected beam and an interface wave component. The influence of the beamwidth parameter of the bounded beam on the decomposition into complex harmonic waves explains the nonobservance of particular Lamb waves at certain angular regions, e.g. near the longitudinal critical angle. This representation holds the possibility to predict optimum parameters to observe strong Lamb wave radiation which can be of great importance in the field of acoustic microscopy.
Sorption Behavior and Morphology of Plutonium in the Presence of Goethite at 25 and 80C

In this study, we examined the sorption behavior of Pu at elevated temperatures in the presence of one relevant mineral, goethite ({alpha}-FeOOH), over a range of concentrations that span solubility-controlled to adsorption-controlled concentrations. We focused on the sorptive behavior of two common forms of Pu: aqueous Pu(IV) and intrinsic Pu(IV) nano-colloids at 25 and 80 C in a dilute pH 8 NaCl/NaHCO{sub 3} solution. The morphology of Pu sorbed to goethite was characterized using transmission electron microscopy (TEM). We examined the relative stability of PuO{sub 2} precipitates, PuO{sub 2} nano-colloids, Pu{sub 4}O{sub 7} surface precipitates, and monomeric sorbed Pu as a function of temperature and over a time scale of months.
A silica gel supported dual acidic ionic liquid: an efficient and recyclable heterogeneous catalyst for the one-pot synthesis of amidoalkyl naphthols

A supported dual acidic ionic liquid catalyst was prepared via anchoring 3-sulfobutyl-1-(3-propyltriethoxysilane) imidazolium hydrogen sulfate onto silica gel by covalent bonds. The novel immobilized acidic ionic liquid effectively catalyzed the one-pot synthesis of amidoalkyl naphthols by the multicomponent condensation of aldehydes with 2-naphthol and amides under solvent-free conditions. Moreover, the catalyst could be recycled six-times without a significant loss of catalytic activity.
Insoluble Content, Ionic Composition, Density, and X-Ray Diffraction Spectra of 6 Evaporites from Niger Republic

Some physicochemical (insoluble content, ionic composition, density, and X-ray diffraction spectra) characteristics of Nigerien evaporites were investigated in this study. The results obtained showed that trona is the main mineral contained in Agadez, Dirkou, Niamey, and Zinder evaporites while thenardite and halite constitute the major minerals in Bilma and Tabalak evaporites, respectively. In addition, all evaporites samples investigated revealed the presence of quartz and halite. Other interesting minerals (calcite, gypsum, sylvite, aphthitalite, nahcolite, illite, burkeite, kaolinite, griceite, and talc) were also detected. The use of Agadez, Dirkou, Niamey, and Zinder evaporites as catalyst to accelerate cowpea cooking is due to bicarbonates ions present in trona. Bilma and Tabalak evaporites employed in animal feeding are due to the halite contained in a significant quantity.
Effective Atomic Displacements in α-Zirconium under Neutron Irradiation

A computer simulation of atomic displacements cascades in α-zirconium is performed by molecular dynamics method. The dependence of the fraction of surviving defects on the PKA energy (in the range from 0.1 to 20 keV) is revealed for the initial temperature of the material of 0 and 600 K. Group neutron cross sections of the effective displacement under neutron irradiation are prepared. The effective dpa rates for zirconium in neutron spectra of different reactors are evaluated. These values are about four times lower than the corresponding values of conventional dpa rates for neutron energies from 0.5 MeV and higher.
Marangoni boundary layer flow and heat transfer of copper-water nanofluid over a porous medium disk

In this paper we present a study of the Marangoni boundary layer flow and heat transfer of copper-water nanofluid over a porous medium disk. It is assumed that the base fluid water and the nanoparticles copper are in thermal equilibrium and that no slippage occurs between them. The governing partial differential equations are transformed into a set of ordinary differential equations by generalized Karman transformation. The corresponding nonlinear two-point boundary value problem is solved by the Homotopy analysis method and the shooting method. The effects of the solid volume fraction, the permeability parameter and the Marangoni parameter on the velocity and temperature fields are presented graphically and analyzed in detail.
Effect of potash on renal profile of albino wistar rats

This study is intended to investigate the effect of Potash on renal function. Twenty four (24) Albino wistar rats with mean weight of 126.3±23.9g were used. They were subdivided into four groups -A, B, C and D (n=6 each); with A serving as control while B, C and D served as test groups. Group A received normal feed and water while B, C and D received 3.0g/kg, 6.0g/kg and 9.0g/kg of potash per body weight for 21 days respectively. At the end of the experiment, the animals were sacrificed under light anesthesia to obtain blood samples for the estimation of renal function parameters. Sodium, Potassium, Chloride, Urea, Uric acid and Creatinine was analyzed using standard analytical chemical methods. The results showed a significant (P 0.05) from that of the control. Our findings therefore, suggest that potash may have dosage dependent nephrotoxic and weight reduction potentials and by implication, may induce growth retardation. This indicates therefore, that potash is toxic to the kidney and there is need for further studies.
Chemical and Biological Point Sensors for Homeland Defense

As part of an effort to develop a portable probe for real-time detection of chemical agents using Raman spectroscopy, the kinetics of adsorption of selected volatile organic molecules on high surface area silica supports was studied using Raman spectroscopy with 785-nm excitation. Two aspects of this work are described. First, the affinity of organic molecules in a flowing gas stream to ultraporous mineralized wood stubstrates was shown to be very high under a variety of respresentative conditions, suggesting that a sensor based on in-situ Raman measurement of adsorption rates may be feasible. Moreover, the mechanism of adsorption was found to vary for different molecules, thereby promoting a high degree of chemical specificity. Second, the possibility of using Surface-Enhanced Raman Spectroscopy (SERS) to enhance Raman signals and thereby improve the sensitivity of an in-situ Raman probe even further was demonstrated.
Industrial Crystallization: Fundamentals and Applications

1. Thermodynamics, crystallisation methods and supersaturation 2. Characterisation of a crystalline product 3. Basic process design for crystallisation 4. Nucleation 5. Crystal growth 6. Agglomeration 7. The population balance equation 8. Batch crystallisation 9. Measurement techniques 10. Industrial crystallisers 11. Precipitation 12. Melt crystallisation 13. Additives and impurities 14. Polymorphism.
Effect of planting methods and levels of nitrogen on incidence of early shoot borer, Chilo infuscatellus Snellen in sugarcane

A field experiment was conducted at the farm of Regional Research Station, Uchani, Karnal, CCS Haryana Agricultural University, Hisar during 2017-2018 to evaluate the effect of planting methods and levels of nitrogen on the incidence of early shoot borer, Chilo infuscatellus Snellen in some sugarcane genotypes. Two planting methods i.e. paired row and conventional method with three doses of nitrogen, 150, 180 and 210 kg/ha were tested on three differently maturing sugarcane varieties CoH 160 (early maturing), CoH 167 (mid maturing) and CoH 150 (late maturing) to observe their effect on the incidence of early shoot borer in sugarcane. The incidence of early shoot borer was maximum (7.14, 12.03 and 5.37%) in CoH 160 and the minimum (3.45, 4.81 and 2.96%) in CoH 167 during April, May and June, 2017, respectively. Early shoot borer incidence was minimum (3.94, 6.65 and 2.85%) at 150 kg N/ha and maximum (6.29, 9.32 and 4.76%) at 210 kg N/ha during April, May and June, respectively. With the present findings, it can be concluded that with the increase in nitrogen dose there was increase in the incidence of above mentioned pest. Incidence of early shoot borer was not affected significantly with different planting methods.
The Use of 31-Phosphorus Magnetic Resonance Spectroscopy to Study Brain Cell Membrane Motion- Restricted Phospholipids

Until relatively recently, the only way non-invasively to study brain cell membrane phospholipids in humans in vivo has been through the quantification of membrane phospholipid metabolism by means of ascertaining the levels of phosphomonoesters and phosphodiesters from 31-phosphorus neurospectroscopy scans. However, this only gives an indirect measure of the cell membrane phospholipid molecules. Ideally, one would want to study the brain cell membrane motion-restricted phospholipids directly, but it has previously proved almost impossible to obtain high-resolution magnetic resonance spectra of membrane phospholipids in living tissues owing to the large chemical-shift anisotropy of the 31-phosphorus confined to what is, in terms of nuclear magnetic resonance, the relatively rigid structure of the cell membrane, whether this be the external cell membrane or the membrane of an intracellular organelle.
ENZYME ACTIVITY PROBE AND GEOCHEMICAL ASSESSMENT FOR POTENTIAL AEROBIC COMETABOLISM OF TRICHLOROETHENE IN GROUNDWATER OF THE NORTHWEST PLUME, PADUCAH GASEOUS DIFFUSION PLANT, KENTUCKY

The overarching objective of the Paducah Gaseous Diffusion Plant (PGDP) enzyme activity probe (EAP) effort is to determine if aerobic cometabolism is contributing to the attenuation of trichloroethene (TCE) and other chlorinated solvents in the contaminated groundwater beneath PGDP. The site-specific objective for the EAP assessment is to identify if key metabolic pathways are present and expressed in the microbial community--namely the pathways that are responsible for degradation of methane and aromatic (e.g. toluene, benzene, phenol) substrates. The enzymes produced to degrade methane and aromatic compounds also break down TCE through a process known as cometabolism. EAPs directly measure if methane and/or aromatic enzyme production pathways are operating and, for the aromatic pathways, provide an estimate of the number of active organisms in the sampled groundwater. This study in the groundwater plumes at PGDP is a major part of a larger scientific effort being conducted by Interstate Technology and Regulatory Council (ITRC), U.S. Department of Energy (DOE) Office of Environmental Management (EM), Savannah River National Laboratory (SRNL), and North Wind Inc. in which EAPs are being applied to contaminated groundwater from diverse hydrogeologic and plume settings throughout the U.S. to help standardize their application as well as their interpretation. While EAP data provide key information to support the site specific objective for PGDP, several additional lines of evidence are being evaluated to increase confidence in the determination of the occurrence of biodegradation and the rate and sustainability of aerobic cometabolism. These complementary efforts include: (1) Examination of plume flowpaths and comparison of TCE behavior to 'conservative' tracers in the plume (e.g., {sup 99}Tc); (2) Evaluation of geochemical conditions throughout the plume; and (3) Evaluation of stable isotopes in the contaminants and their daughter products throughout the plume. If the multiple lines of evidence support the occurrence of cometabolism and the potential for the process to contribute to temporal and spatial attenuation of TCE in PGDP groundwater, then a follow-up enzyme probe microcosm study to better estimate biological degradation rate(s) is warranted.
Student Perceptions of How Faculty Advising Supports the Academic Persistence of Students of Color at One Predominantly White Institution

viii LIST OF TABLES . x CHAPTER I INTRODUCTION . 1 Statement of the Problem . 8 Purpose of the Study . 11 Research Questions . 11 Significance of the Study . 12 Summary of Conceptual Framework . 14 Summary of Methodology . 14 Definition of Terms . 16 Assumptions of the Study . 17 Limitations to the Study . 17 Summary . 17 Organization of the Remainder of the Study . 18 CHAPTER II LITERATURE REVIEW . 19 Overview of Racial Diversity on College Campuses . 19 Disparate Educational Attainment . 22 Campus Racial Climate . 24 Microaggressions on College Campuses . 27 Texas Tech University, Wendy Yoder, May 2019 v Whiteness on College Campuses . 29 Supporting Racial Diversity on College Campuses . 31 Recruiting for Racial Pluralism . 31 Students in Transition . 32 Supporting Students of Color on College Campuses . 34 Confronting Whiteness as the Cultural Norm . 35 Academic Advising in Higher Education . 36 Advising Models . 38 Advising Approaches . 43 Use of Advising to Retain Students . 47 Advising to Support Students of Color . 49 Advising Perceptions of Students of Color . 51 Conceptual Framework of the Study . 52 Prior Research Using Harper’s Anti-Deficit Achievement Framework . 54 Summary . 55 CHAPTER III METHODOLOGY . 57 Restatement of the Purpose of the Study . 57 Restatement of the Research Questions . 57 Research Design . 58 Establishing the Paradigm.58 Study Type . 60 Study Setting . 62 Participants and Sampling.63 Texas Tech University, Wendy Yoder, May 2019 vi Data Collection Processes . 65 Data Analysis Processes . 69 Trustworthiness of the Study . 71 Context of the Study and the Researcher . 73 Context of the Study . 73 Context of the Researcher . 74 Summary . 76 CHAPTER IV – FINDINGS . 78 Summary of the Research Design . 78 Data Collection Processes . 79 Data Analysis Processes . 83 Study Institution and Participant Profiles . 85 Study Institution Profile . 85 Participant Profiles . 86 Findings . 90 Advising Impact on Persistence . 90 Advising Experiences that Support or Hinder Student Persistence . 98 Recommendations for Supporting Students of Color at a PWI . 102 Summary . 112 CHAPTER V – DISCUSSION . 114 Overview of the Study . 114 Discussion of the Findings . 118 Advising Impact on Persistence . 119 Texas Tech University, Wendy Yoder, May 2019 vii Advising Experiences that Support or Hinder Student Persistence . 125 Recommendations for Supporting Students of Color at a PWI . 128 Implications for Higher Education Practice . 132 Recommendations for Higher Education Practice . 136 Recommendations for Future Research . 140 Conclusion . 142 REFERENCES . 145 APPENDIX A . 166 APPENDIX B . 167 APPENDIX C . 168 APPENDIX D . 169 APPENDIX E . 170 APPENDIX F . 172 Texas Tech University, Wendy Yoder, May 2019
Sun-induced fluorescence: A new tool for precision farming

Results of ground based experiments on spectral reflectance of dock leaves using a ZEISS spectrometer MCS501 UV-NIR with 2.5 nm resolution clearly show the well known induction kinetics of chlorophyll fluorescence when dark adapted leaves were exposed to continuous illumination. This observed feature demonstrates the origin of the transient behavior of reflectance caused by natural or sun-induced fluorescence. The time constant of the decline of sun induced chlorophyll fluorescence is identical to the time constant obtained simultaneously using a PAM (Pulse Amplitude Modulation) fluorometer. Results of airborne measurements with the sensor ROSIS (Reflective Optics System Imaging Spectrometer) demonstrate for the first time that sun induced chlorophyll fluorescence can be derived from airborne hyperspectral reflectance data. The new method presented here uses the spectral absorption feature of atmospheric oxygen at 762 nm, which fits better with the wavelength of chlorophyll fluorescence than the Fraunhofer absorption line at 656 nm. The results from ROSIS show maps of sun-induced chlorophyll fluorescence of green vegetation. New spatial and temporal features are observable on agricultural fields supporting the hypothesis that information on photosynthesis and plant stress may be extracted in the future from areal observation of sun-induced fluorescence.
Influence of twin row production system and levels of nitrogen on growth and yield of rabi maize (Zea mays L.)

A field experiment was conducted at College Agronomy Farm, B. A. College of Agriculture, Anand Agricultural University, Anand with a view to study influence of twin row production system and levels of nitrogen on growth and yield of rabi maize (Zea mays L.) during rabi season of the year 2017-18. The experiment consisted of twelve treatment combinations comprised of three row systems and four levels of nitrogen tested under Split Plot Design (SPT) with four replication. The results revealed that twin row system of 30-60 cm x 20 cm recorded maximum plant height at 60 DAS and at harvest, higher plant dry biomass and crop growth rate at 60 DAS. Relative growth rate (g/g/day) remained unaffected due to different row systems. Application of 140 kg N/ha recorded significantly higher plant height at 60 DAS and at harvest, plant dry biomass at 60 DAS, crop growth rate at 30-60 DAS and relative growth rate (g/g/day) at 0-30 DAS. Among all the treatment combinations, treatment combination R2N4 (30-60 cm x 20 cm + 140 kg/ha) recorded significantly higher plant dry biomass (56.88 g/plant) and grain yield (5378 kg/ha) while treatment combination R1N4 (30-45 cm x 20 cm + 140 kg/ha) recorded significantly higher Stover yield (12825 kg/ha).