1,105,615 research outputs found
A Flavor Perception Game Designed to Introduce Basic Chemical Sensation of Taste Modalities to Undergraduate Nursing and Exercise Sciences Students
The Flavor Perception Game was designed with the goals of developing an interactive and hands-on activity, providing a platform to review chemical senses of the five tastes, promoting student investment in the course material, and providing a basis for discussion on chemical senses of the five tastes. Knowledge of taste sensation is useful for nursing and exercise sciences students, as human physiology is integral to both baccalaureate curricula. The game is inexpensive, easy to incorporate into a 50-minute lecture period, and free of chocolate allergens. Student participants (N=34) tasted three candies and completed a voluntary anonymous poll regarding their detection of the presence of umami, bitter, sweet, salty and/or sour taste modalities in the different candies. During the three stages of this classroom game, a total of 214 taste selections were made, following which students discussed various aspects of taste sensation including its importance in healthcare
Chemical and sensory characteristics of the sparkling and natural ciders stored in different types of containers
[EN] The cider industry is becoming more prolific in many parts of the world, and with the growing
demand for cider comes a growing demand for high-quality ciders from traditional cider-growing regions. The
main goal of the project was to study the chemical and sensory characteristics of the sparkling and natural
ciders stored in different types of containers after three month of preservation at 23¿C in the temperature
controlled storage room. Sparkling is a sweet, carbonated cider formulated for the export market, while the
natural is a traditional dry and acidic cider, but appealing to cider enthusiasts. Both ciders wereput into
different containers, including plastic kegs, beer bottles, and plastic bottles systems. Over the course of three
months, samples were taken from the ciders and subject to chemical and sensory analyses for quality control,
with kegs and glass bottles retaining cider quality well. Theresults show that plastic and metal kegs seem to
have preserved Natural cider better than the control standard bottles, while plastic bottles system did a worse
job preserving the cider. Beer bottles did a good job in preserving the cider, as well.Plotkoski, D.; Aleixandre Tudo, J.; Aleixandre Benavent, JL. (2016). Chemical and sensory characteristics of the sparkling and natural ciders stored in different types of containers. International journal of research studies in agricultural sciences. 2(9):21-34. https://doi.org/10.20431/2454-6224.0209004S21342
AUTHOR’S ERRATUM
AUTHOR’S ERRATUM
Dear Editor,
I would like to publish the following errata to correct the paper titled:
“Solubility of Thiamine in Pure and Mixed Solvents in Function of Temperature” by L. C. P. Borges, A. H. R. Rezende, A. C. Granato, and R. F. Pires published in Chem. Biochem. Eng. Q. 29 (1) (2015) 19–23 – issue dedicated to CHISA 2014.
On page 22, in the section ACKNOWLEDGEMENTS, the following text:
“This work was granted financial support from CNPQ (Proc. 485171/2013-9).”
should be replaced with:
“This work was granted financial support from CNPQ (Proc. 485171/2013-9), FAPEMIG (APQ-01638-13) and UFTM.”
Prof. Dr. Ricardo Francisco Pires
email: [email protected]
Federal University of Triângulo Mineiro
Institute of Technological and Exact Sciences – ICTE
Chemical Engineering Department
Avenue Doutor Randolfo Borges Junior, 1250 – Univerdecidade, Uberaba – MG
Postal Address: 38064-200
Tel. +55(34) 3331-300
Using a conceptual change approach as a teaching strategy for improving learners' understanding of Chemical Change in Physical Sciences.
Magister Educationis - MEd (Mathematics and Science Education)The purpose of this study is to investigate the use of a Conceptual Change Approach as a teaching strategy to improve learners' understanding of Chemical Change in Physical Sciences. In addition, learners' attitudes toward chemistry as a school subject and toward Conceptual Change texts were investigated. Moreover, learners' science process skills were also investigated. The study was underpinned by Conceptual Change Theory and Constructivism. The sample included 34 Grade 11 learners doing Physical Sciences. The case study is a secondary school in the
Eastern Cape. For the purposes of this study both quantitative and qualitative research methods were used. Learners were given a pre- test and a post-test and an intervention in the form of a Conceptual Change text lesson. Thereafter, focus group interviews were used to examine learners' understanding in greater detail. Findings revealed that learners have several misconceptions that hinder learning related to chemical change. It is therefore imperative to find ways for remediation of these misconceptions. The results also showed that instruction based on the Conceptual Change Approach in which Conceptual Change Texts were used, caused significantly better attainment of concepts on chemical change, better remediation of misconceptions and enhanced understanding of chemical change. This study provides insight into the use of Conceptual Change as a teaching strategy to improve learners' understanding of challenging areas in Physical Sciences
Measurements of Gas‐Phase Inorganic and Organic Acids from Biomass Fires by Negative‐Ion Proton‐Transfer Chemical‐Ionization Mass Spectrometry
[1] Emissions from 34 laboratory biomass fires were investigated at the combustion facility of the U.S. Department of Agriculture Fire Sciences Laboratory in Missoula, Montana. Gas-phase organic and inorganic acids were quantified using negative-ion proton-transfer chemical-ionization mass spectrometry (NI-PT-CIMS), open-path Fourier transform infrared spectroscopy (OP-FTIR), and proton-transfer-reaction mass spectrometry (PTR-MS). NI-PT-CIMS is a novel technique that measures the mass-to-charge ratio (m/z) of ions generated from reactions of acetate (CH3C(O)O−) ions with inorganic and organic acids. The emission ratios for various important reactive acids with respect to CO were determined. Emission ratios for isocyanic acid (HNCO), 1,2 and 1,3-benzenediols (catechol, resorcinol), nitrous acid (HONO), acrylic acid, methacrylic acid, propionic acid, formic acid, pyruvic acid, and glycolic acid were measured from biomass burning. Our measurements show that there is a significant amount of HONO in fresh smoke. The NI-PT-CIMS measurements were validated by comparison with OP-FTIR measurements of HONO and formic acid (HCOOH) and with PTR-MS measurements of HCOOH
Fast Room-Temperature Detection of Terahertz Quantum Cascade Lasers with Graphene-Loaded Bow-Tie Plasmonic Antenna Arrays
We present a fast room-temperature terahertz detector based on interdigitated bow-tie antennas contacting graphene. Highly efficient photodetection was achieved by using two metals with different work functions as the arms of a bow-tie antenna contacting graphene. Arrays of the bow-ties were fabricated in order to enhance the responsivity and coupling of the incoming light to the detector, realizing an efficient imaging system. The device has been characterized and tested with a terahertz quantum cascade laser emitting in single frequency around 2 THz, yielding a responsivity of ∼34 μA/W and a noise-equivalent power of ∼1.5 × 10 W/Hz.R.D., Y.R., and H.E.B. acknowledge financial support from the Engineering and Physical Sciences Research Council (Grant No. EP/J017671/1, Coherent Terahertz Systems). S.H. acknowledges funding from EPSRC (Grant No. EP/K016636/1, GRAPHTED). H.L. and J.A.Z. acknowledge financial support from the EPSRC (Grant No. EP/L019922/1). J.A.A.-W. acknowledges a Research Fellowship from Churchill College, Cambridge. H.J.J. thanks the Royal Commission for the Exhibition of 1851 for her Research Fellowship.This is the final version of the article. It first appeared from American Chemical Society via https://doi.org/10.1021/acsphotonics.6b0040
The influence of strip cropping and weed control methods on weed diversity in dent maize (Zea mays L.), narrow-leafed lupin (Lupinus angustifolius L.) and oats (Avena sativa L.)
The experiment was conducted in 2008–2010 at the Experimental Station of the Faculty of Agricultural Sciences in Zamość, University of Life Sciences in Lublin. The research design included two factors: I. Method of cultivation – sole cropping and strip cropping (the cultivation of three plants: maize, narrow-leafed lupin and oats, in neighboring strips); II. Weed control method – mechanical and chemical. The subject of this study was weed infestation in maize, narrow-leafed lupin and oats. The greatest diversity of weeds was found in the narrow-leafed lupine crop, while the lowest diversity in maize. The dominant weed species in maize, lupine and oats were Echinochloa crus-galli, Chenopodium album and Galinsoga parviflora which ranged from 34% to 99% of the total number of weeds. Strip cropping clearly reduced the number of weeds per unit area in the narrow-leafed lupin and oat crops as well as the aboveground dry weight of weeds in all plant species. Chemical weed control significantly decreased both the number and weight of weeds in comparison with the mechanical method
Chemoinformatics Research at the University of Sheffield: A History and Citation Analysis
This paper reviews the work of the Chemoinformatics Research Group in the Department of Information Studies at the University of Sheffield, focusing particularly on the work carried out in the period 1985-2002. Four major research areas are discussed, these involving the development of methods for: substructure searching in databases of three-dimensional structures, including both rigid and flexible molecules; the representation and searching of the Markush structures that occur in chemical patents; similarity searching in databases of both two-dimensional and three-dimensional structures; and compound selection and the design of combinatorial libraries. An analysis of citations to 321 publications from the Group shows that it attracted a total of 3725 residual citations during the period 1980-2002. These citations appeared in 411 different journals, and involved 910 different citing organizations from 54 different countries, thus demonstrating the widespread impact of the Group's work
Synthesis of mesoporous MCM-41 materials with low power microwave heating
Crystalline, high surface area, hexagonal mesoporous MCM-41 having uniform pore sizes and good thermal stability was successfully synthesized at 90-120oC in 30 minutes using low power microwave irradiation. This appears to be the first comprehensive and quantitative investigation of the comparatively rapid synthesis of mesoporous MCM-41 using low power microwave heating of 80W (90oC) and 120W (120oC). The influence of reaction temperature and the duration of heating were carefully investigated and the calcined MCM-41 materials
were characterized by XRD, SEM, TEM, nitrogen adsorption, TGA and FTIR. The
mesoporous MCM-41 product synthesized in 30 minutes at 120W and calcined at 550oC had a very high surface area of 1438 m2/g and was highly ordered, contained uniform pores with diameters in the range of 3.5-4.5 nm. The wall thickness of the materials highly depended on the power of the microwave energy used during the synthesis. Synthesis of the mesoporous MCM-41 products at 120oC resulted with a structure having thinner walls. The mesoporous MCM-41 materials synthesized in the present work had good thermal stability
Monitoring and evaluation of Terni (Central Italy) air quality through spatially resolved analyses
A study of spatial variability of PM10 elemental components was conducted in Terni city (Central Italy), situated in an intramountain depression characterized by the presence of several particulate matter emission sources. The meteorological conditions of Terni basin limit the dispersion and enhance the accumulation of the atmospheric pollutants. Thanks to the utilization of new samplers (Smart Sampler), used for the first time and working in parallel at 23 sampling sites, spatially resolved data were obtained. Localizations of the samplers were chosen in order to evaluate the impact of different local PM10 sources. Chemical composition of the samples was determined in combination with a chemical fractioning procedure, that allowed us to discriminate watersoluble and residual fractions of analyzed elements in which proved to be a valuable approach for increasing selectivity of elements as source tracers. Spatial variability of elements underlined the contribution of local emission sources and the different dispersion capacity of each element. Terni city resulted to be an ideal area to test and validate a new experimental method for the acquisition of spatially resolved data providing the possibility to properly evaluate the spatial variability of PM10 and its chemical components
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