Herein, we report on the experimental measurements for estimated relative mobility shifts caused by changes in mass distribution from isotopic substitutions isotopologues and isotopomers with high-resolution cyclic ion separations. By utilizing unlabeled fully labeled same (i.e., 2H or 13C), created a highly precise scale each set analyzed to determine magnitude of such thus calculate deviations expected, theoretical reduced contributions. We observed various (e.g.,...

Recent research has demonstrated the unambiguous positive effects of active learning in a variety college-level courses. We report implementation and assessment 50 minute active-learning in-class activity to conceptualize light absorbance, reflectance, transmittance, coupled with writing-to-learn exercise. The is suitable classroom setting using portable hand-held sensors samples, including textiles food-dye solutions. included quasi-experimental design, which 116 students an introductory...

Service-learning (SL) is an active learning approach that connects the knowledge a student acquires in classroom to application benefits community. Increasingly popular chemistry curriculum, service-learning reported provide including improved cognitive goals; increased academic, interpersonal, and leadership skills; ability apply course concepts real-world situations; community engagement. For work here, analytical laboratory was modified include component with goal of allowing students...

The potential of total excitation–emission fluorescence microscopy combined with multiway chemometric analysis was investigated for the nondestructive forensic textile fibers. four pairs visually indistinguishable fibers consisted nylon 361 dyed acid yellow 17 and 23, acetate satin 105B disperse blue 3 14, polyester 777 red 1 19, acrylic 864 basic green 4. Excitation emission matrices were recorded aid an inverted microscope a commercial spectrofluorimeter. full information content processed...

Glass and fused-quartz nanopore membranes containing a single conically shaped pore are promising solid supports for lipid bilayer ion-channel recordings due to the high inherent stability of bilayers suspended across orifice, as well favorable electrical properties glass fused quartz. Fluorescence microscopy is used here investigate structure function pressure applied membrane. When positive bilayer, from interior relative exterior bulk solution, insertion or reconstitution operative ion...

Extrusion of hydrated lipid suspensions is frequently employed to produce vesicles uniform size, and the resulting are often reported be unilamellar. We describe a method for quantitative fluorescence image analysis individual obtain information on lamellarity, structure produced by extrusion. In contrast methods bulk analysis, microscopy provides about vesicles, rather than averaged results, heterogeneities in vesicle populations can characterized. Phosphatidylcholine containing small...

Fischer−Tropsch synthesis of diesel range straight-chain hydrocarbons from CO and H2 over a cobalt nanoparticle catalyst supported by mesoporous silica xerogel is reported. A possible advantage sol−gel-derived supports the tunability their porosity to favor hydrocarbons. The preparation supports, optimal loading with cobalt, percent conversion syngas hydrocarbons, gas chromatography−mass spectrometry analysis product distribution, characterization catalysts are

Detection of single, fluorescently labeled biomolecules is providing a powerful approach to measuring molecular transport, biomolecular interactions, and localization in biological systems. Because the molecules interest rarely exhibit sufficient intrinsic fluorescence allow observation individual molecules, they are usually with fluorescent dye proteins, semiconductor nanocrystals or quantum dots, doped silica polymer nanospheres their detection. Differences photophysical spectral...

Encapsulation of molecules in phospholipid vesicles provides unique opportunities to study chemical reactions small volumes as well the behavior individual proteins, enzymes, and ribozymes a confined region without requiring tether immobilize molecule surface. These experiments generally depend on generating predictable loading with numbers target thus raise significant measurement challenge, namely, quantify molecular occupancy at single-molecule level. In this work, we describe an imaging...

Identification methods for single textile fibers are in demand forensic applications, and nondestructive with minimal pretreatment have the greatest potential utility. Excitation-emission luminescence data provide a three-dimensional matrix comparison of single-fiber dyes, these enhanced by principal component analysis using statistical figure merit. No dye extraction required to sample spectra from fiber. This approach has been applied compare closely matched pairs, acid blue (AB) 25 41...

The use of phospholipid vesicles as reaction containers, vehicles for pharmaceutical drug delivery, and model systems cells has prompted the development new methods analyzing structure their contents. pH interior is particular interest when analytes are encapsulated concentrated with a gradient. While generally measured large populations vesicles, we report measurement individual buffer contents titrated by transfer N-methylbutylamine (NMBA) into vesicle initially acidic within along small...

Discovering common origins of trace evidential textile fibers can be a challenging task when fiber structure or dye composition does not provide exclusive identifying information. Introduction new chemical species after mass production and distribution may exploited to its history identify the origin fibers. In this article, fluorescence microscopy is used examine alteration in spectral fingerprint single resulting from exposure commonly detergents that contain fluorescent whitening agents....

Undergraduate analytical chemistry courses emphasize fundamental stoichiometric and physicochemical techniques with statistical analysis linear calibrations. Higher-level data may not be included in the college junior-level curriculum, but widely available software enables more complex to accessible. In this work, activities train students multicomponent spectral curve fitting (using Microsoft Excel's Solver) utilizing matrix algebra were incorporated within a large-enrollment undergraduate...

Measurement of plasma metanephrine and normetanephrine concentrations has recently been acknowledged as one the leading tests for diagnosis neuroendocrine tumor, pheochromocytoma (1). The occurrence tumor is rare, it often difficult to diagnose. wide spectrum signs symptoms includes hypertension, headaches, diaphoresis. Located primarily in adrenal gland, these tumors produce excess catecholamines their metabolites. Assays have developed measure metanephrines both urine. Although all...

Throughout the undergraduate curriculum, students utilize linearized forms of nonlinear equations—from Clausius–Clapeyron equation in general chemistry to Michaelis–Menten biochemistry. Presenting equations as a fait accompli may be lost opportunity empower with understanding process linearization an analytical tool. This work describes series activities that can implemented and spaced throughout curriculum. The are low-cost chemical-free, so they lecture setting. Distributed practice allows...

Artificial water-treatment wetlands can reduce nitrogen and phosphorous nutrient concentrations in wastewater effluent to improve water quality decrease eutrophication natural waters. The Orlando Easterly Wetlands (OEW) is an engineered wetland that polishes 57 million liters of per day, lowering the total through biological, physical, chemical processes. In addition purifying water, provide habitat for avian, mammalian, reptilian macroinvertebrate species. Previous research has shown avian...

An NMR-guided procedure for refining crystal structures has recently been introduced and shown to produce unusually high resolution structures.

Shape selectivity is important in reversed-phase liquid chromatographic separations, where stationary phases are capable of separating geometric isomers, thereby resolving solutes based on their three-dimensional structure or shape rather than other chemical differences. Numerous studies have been carried out using n-alkyl-chain-modified columns to understand how molecular affects retention. For polycyclic aromatic hydrocarbons (PAHs), it was found that planar compounds were selectively...

Sales of low-calorie sweeteners are increasing in the Unites States, with sucralose representing second largest U.S. market share. Since >99% ingested is excreted as parent compound, it represents a contaminant emerging concern and has been proposed an indicator pollution natural waters by anthropogenic waste. Many report that increasingly omnipresent surface, coastal, drinking water. Given consumption sweeteners, changes influent effluent concentrations presage their waters. The aim this...

Informal learning (IL) venues such as museums, zoos, scouting, national parks, and community activities are increasingly recognized for their important role in enhancing the public understanding of science. Many benefits to students who participate rich informal experiences reported literature, including improvements scientific reasoning skills, percentages enrolling science, technology, engineering, math (STEM) majors, completion college degrees. The research herein analyzes potential...