Determination of the δ15N of nitrate in solids; RSIL lab code 2894
Coplen, Tyler B.; Qi, Haiping; Revesz, Kinga; Casciotti, Karen; Hannon, Janet E.
2007-01-01
The purpose of the Reston Stable Isotope Laboratory (RSIL) lab code 2894 is to determine the δ15N of nitrate (NO3-) in solids. The nitrate fraction of the nitrogen species is dissolved by water (called leaching) and can be analyzed by the bacterial method covered in RSIL lab code 2899. After leaching, the δ15N of the dissolved NO3- is analyzed by conversion of the NO3- to nitrous oxide (N2O), which serves as the analyte for mass spectrometry. A culture of denitrifying bacteria is used in the enzymatic conversion of NO3- to N2O, which follows the pathway shown in equation 1: NO3- → NO2- → NO → 1/2 N2O (1) Because the bacteria Pseudomonas aureofaciens lack N2O reductive activity, the reaction stops at N2O, unlike the typical denitrification reaction that goes to N2. After several hours, the conversion is complete, and the N2O is extracted from the vial, separated from volatile organic vapor and water vapor by an automated -65 °C isopropanol-slush trap, a Nafion drier, a CO2 and water removal unit (Costech #021020 carbon dioxide absorbent with Mg(ClO4)2), and trapped in a small-volume trap immersed in liquid nitrogen with a modified Finnigan MAT (now Thermo Scientific) GasBench 2 introduction system. After the N2O is released, it is further purified by gas chromatography before introduction to the isotope-ratio mass spectrometer (IRMS). The IRMS is a Thermo Scientific Delta V Plus continuous flow IRMS (CF-IRMS). It has a universal triple collector, consisting of two wide cups with a narrow cup in the middle; it is capable of simultaneously measuring mass/charge (m/z) of the N2O molecule 44, 45, and 46. The ion beams from these m/z values are as follows: m/z = 44 = N2O = 14N14N16O; m/z = 45 = N2O = 14N15N16O or 14N14N17O; m/z = 46 = N2O = 14N14N18O. The 17O contributions to the m/z 44 and m/z 45 ion beams are accounted for before δ15N values are reported.
Determination of the delta(2H/1H)of Water: RSIL Lab Code 1574
Revesz, Kinga; Coplen, Tyler B.
2008-01-01
Reston Stable Isotope Laboratory (RSIL) lab code 1574 describes a method used to determine the relative hydrogen isotope-ratio delta(2H,1H), abbreviated hereafter as d2H of water. The d2H measurement of water also is a component of the National Water Quality Laboratory (NWQL) schedules 1142 and 1172. The water is collected unfiltered in a 60-mL glass bottle and capped with a Polyseal cap. In the laboratory, the water sample is equilibrated with gaseous hydrogen using a platinum catalyst (Horita, 1988; Horita and others, 1989; Coplen and others, 1991). The reaction for the exchange of one hydrogen atom is shown in equation 1.
Determination of the δ15N and δ18O of nitrate in solids; RSIL lab code 2897
Coplen, Tyler B.; Qi, Haiping; Revesz, Kinga; Casciotti, Karen; Hannon, Janet E.
2007-01-01
The purpose of the Reston Stable Isotope Laboratory (RSIL) lab code 2897 is to determine the δ15N and δ18O of nitrate (NO3-) in solids. The NO3- fraction of the nitrogen species is dissolved by water (called leaching) and can be analyzed by the bacterial method covered in RSIL lab code 2900. After leaching, the δ15N and δ18O of the dissolved NO3- is analyzed by conversion of the NO3- to nitrous oxide (N2O), which serves as the analyte for mass spectrometry. A culture of denitrifying bacteria is used in the enzymatic conversion of NO3- to N2O, which follows the pathway shown in equation 1: NO3- → NO2- → NO → 1/2 N2O (1) Because the bacteria Pseudomonas aureofaciens lack N2O reductive activity, the reaction stops at N2O, unlike the typical denitrification reaction that goes to N2. After several hours, the conversion is complete, and the N2O is extracted from the vial, separated from volatile organic vapor and water vapor by an automated -65 °C isopropanol-slush trap, a Nafion drier, a CO2 and water removal unit (Costech #021020 carbon dioxide absorbent with Mg(ClO4)2), and trapped in a small-volume trap immersed in liquid nitrogen with a modified Finnigan MAT (now Thermo Scientific) GasBench 2 introduction system. After the N2O is released, it is further purified by gas chromatography before introduction to the isotope-ratio mass spectrometer (IRMS). The IRMS is a Thermo Scientific Delta V Plus continuous flow IRMS (CF-IRMS). It has a universal triple collector, consisting of two wide cups with a narrow cup in the middle; it is capable of simultaneously measuring mass/charge (m/z) of the N2O molecule 44, 45, and 46. The ion beams from these m/z values are as follows: m/z = 44 = N2O = 14N14N16O; m/z = 45 = N2O = 14N15N16O or 14N14N17O; m/z = 46 = N2O = 14N14N18O. The 17O contributions to the m/z 44 and m/z 45 ion beams are accounted for before δ15N values are reported.
Determination of the δ15N of total nitrogen in solids; RSIL lab code 2893
Revesz, Kinga; Qi, Haiping; Coplen, Tyler B.
2006-01-01
The purpose of the Reston Stable Isotope Laboratory (RSIL) lab code 2893 is to determine the δ(15N/14N), abbreviated as δ15N , of total nitrogen in solid samples. A Carlo Erba NC 2500 elemental analyzer (EA) is used to convert total nitrogen in a solid sample into N2 gas. The EA is connected to a continuous flow isotope-ratio mass spectrometer (CF-IRMS), which determines relative difference in the isotope-amount ratios of stable nitrogen isotopes (15N/14N)of the product N2 gas. The combustion is quantitative; no isotopic fractionation is involved. Samples are placed in a tin capsule and loaded into the Costech Zero Blank Autosampler of the EA. Under computer control, samples are dropped into a heated reaction tube that contains an oxidant, where the combustion takes place in a helium atmosphere containing an excess of oxygen gas. Combustion products are transported by a helium carrier through a reduction tube to remove excess oxygen and convert all nitrous oxides into N2 and through a drying tube to remove water. The gas-phase products, mainly CO2 and N2, are separated by a gas chromatograph. The gas is then introduced into the isotope-ratio mass spectrometer (IRMS) through a Finnigan MAT (now Thermo Scientific) ConFlo II interface, which also is used to inject N2 reference gas and helium for sample dilution. The IRMS is a Thermo Scientific Delta V Plus CF-IRMS. It has a universal triple collector, two wide cups with a narrow cup in the middle, capable of measuring mass/charge (m/z) 28, 29, 30, simultaneously. The ion beams from N2 are as follows: m/z 28 = N2 = 14N14N; m/z 29 = N2 = 14N15N primarily; m/z 30 = NO = 14N16O primarily, which is a sign of contamination or incomplete reduction.
Determination of the δ34S of Total Sulfur in Solids: RSIL Lab Code 1800
Revesz, Kinga; Coplen, Tyler B.
2006-01-01
The purpose of Reston Stable Isotope Laboratory Lab (RSIL) Code 1800 is to determine the δ(34S/32S), abbreviated as δ34S, of total sulfur in a solid sample. A Carlo Erba NC 2500 elemental analyzer (EA) is used to convert total sulfur in a solid sample into SO2 gas. The EA is connected to a continuous flow isotope-ratio mass spectrometer (CF-IRMS), which determines the relative difference in stable sulfur isotope-amount ratio (34S/32S) of the product SO2 gas. The combustion is quantitative; no isotopic fractionation is involved. Samples are placed in tin capsules and loaded into a Costech Zero-Blank Autosampler on the EA. Under computer control, samples are dropped into a heated tube reaction tube that combines both the oxidation and the reduction reactions. The combustion takes place in a He atmosphere that contains an excess of oxygen gas at the oxidation zone at the top of the reaction tube. Combustion products are transported by a He carrier through the reduction zone at the bottom of the reaction tube to remove excess oxygen and through a separate drying tube to remove any water. The gas-phase products, mainly CO2, N2, and SO2, are separated by a gas chromatograph (GC). The gas is then introduced into the isotope-ratio mass spectrometer (IRMS) through a Thermo-Finnigan ConFlo II interface, which also is used to inject SO2 reference gas and He for sample dilution. The IRMS is a Thermo-Finnigan DeltaPlus CF-IRMS. It has a universal triple collector with two wide cups and a narrow cup in the middle. It is capable of measuring mass/charge (m/z) 64 and 66 simultaneously. The ion beams from SO2 are as follows: m/z 64 = SO2 = 32S16O16O; and m/z 66 = SO2 = 34S16O16O primarily.
Determination of the δ15N and δ13C of total nitrogen and carbon in solids; RSIL lab code 1832
Revesz, Kinga; Qi, Haiping; Coplan, Tyler B.
2006-01-01
The purpose of the Reston Stable Isotope Laboratory (RSIL) lab code 1832 is to determine the δ(15N/14N), abbreviated as δ15N, and the δ(13C/12C), abbreviated as δ13C, of total nitrogen and carbon in a solid sample. A Carlo Erba NC 2500 elemental analyzer (EA) is used to convert total nitrogen and carbon in a solid sample into N2 and CO2 gas. The EA is connected to a continuous flow isotope-ratio mass spectrometer (CF-IRMS), which determines the relative difference in stable nitrogen isotope-amount ratio (15N/14N) of the product N2 gas and the relative difference in stable carbon isotope-amount ratio (13C/12C) of the product CO2 gas. The combustion is quantitative; no isotopic fractionation is involved. Samples are placed in tin capsules and loaded into a Costech Zero Blank Autosampler on the EA. Under computer control, samples then are dropped into a heated reaction tube that contains an oxidant, where combustion takes place in a helium atmosphere containing an excess of oxygen gas. Combustion products are transported by a helium carrier through a reduction furnace to remove excess oxygen and to convert all nitrous oxides into N2 and through a drying tube to remove water. The gas-phase products, mainly CO2 and N2, are separated by a gas chromatograph. The gas is then introduced into the IRMS through a Finnigan MAT (now Thermo Scientific) ConFlo II interface. The Finnigan MAT ConFlo II interface is used for introducing not only sample into the IRMS but also N2 and CO2 reference gases and helium for sample dilution. The flash combustion is quantitative; no isotopic fractionation is involved. The IRMS is a Thermo Scientific Delta V CF-IRMS. It has a universal triple collector, two wide cups with a narrow cup in the middle; it is capable of measuring mass/charge (m/z) 28, 29, 30 or with a magnet current change 44, 45, 46, simultaneously. The ion beams from these m/z values are as follows: m/z 28 = N2 = 14N/14N; m/z 29 = N2 = 14N/15N primarily; m/z 30 = NO = 14N/16O primarily, which is a sign of contamination or incomplete reduction; m/z 44 = CO2 = 12C16O16O; m/z 45 = CO2 = 13C16O16O primarily; and m/z 46 = CO2 = 12C16O18O primarily.
Determination of the δ13C of dissolved inorganic carbon in water; RSIL lab code 1710
Singleton, Glenda L.; Revesz, Kinga; Coplen, Tyler B.
2012-01-01
The purpose of the Reston Stable Isotope Laboratory (RSIL) lab code 1710 is to present a method to determine the δ13C of dissolved inorganic carbon (DIC) of water. The DIC of water is precipitated using ammoniacal strontium chloride (SrCl2) solution to form strontium carbonate (SrCO3). The δ13C is analyzed by reacting SrCO3 with 100-percent phosphoric acid (H3PO4) to liberate carbon quantitatively as carbon dioxide (CO2), which is collected, purified by vacuum sublimation, and analyzed by dual inlet isotope-ratio mass spectrometry (DI-IRMS). The DI-IRMS is a DuPont double-focusing mass spectrometer. One ion beam passes through a slit in a forward collector and is collected in the rear collector. The other measurable ion beams are collected in the front collector. By changing the ion-accelerating voltage under computer control, the instrument is capable of measuring mass/charge (m/z) 45 or 46 in the rear collector and m/z 44 and 46 or 44 and 45, respectively, in the front collector. The ion beams from these m/z values are as follows: m/z 44 = CO2 = 12C16O16O, m/z 45 = CO2 = 13C16O16O primarily, and m/z 46 = CO2 = 12C16O18O primarily. The data acquisition and control software calculates δ13C values.
Determination of the δ34S of low-concentration sulfate in water; RSIL lab code 1949
Revesz, Kinga; Qi, Haiping; Coplen, Tyler B.
2006-01-01
The purpose of the Reston Stable Isotope Laboratory (RSIL) lab code 1949 is to determine the δ(34S/32S), abbreviated as δ34S, of dissolved sulfate having a concentration less than 20 milligrams per liter. Dissolved sulfate is collected on an anion-exchange resin in the field, eluted in the laboratory with 3 M KCl, and precipitated with BaCl2 at pH 3 to 4 as BaSO4. The precipitated BaSO4 is filtered and dried before introduction into an elemental analyzer (EA) Carlo Erba NC 2500. The EA is used to convert sulfur in a BaSO4 solid sample into SO2 gas, and the EA is connected to a continuous flow isotope-ratio mass spectrometer (CF-IRMS), which determines differences in the isotope-amount ratios of stable sulfur isotopes (34S/32S) of the product SO2 gas. The combustion is quantitative; no isotopic fractionation is involved. Samples are placed in a tin capsule and loaded into the Costech Zero Blank Autosampler of the EA. Under computer control, samples are dropped into a heated reaction tube that combines the oxidation and reduction reactions. The combustion takes place in a helium atmosphere containing an excess of oxygen gas at the oxidation zone at the top of the reaction tube. Combustion products are transported by a helium carrier through the reduction zone at the bottom of the reaction tube to remove excess oxygen and through a separate drying tube to remove any water. The gas-phase products, mainly CO2, N2, and SO2, are separated by a gas chromatograph. The gas is then introduced into the isotope-ratio mass spectrometer (IRMS) through a Finnigan MAT (now Thermo Scientific) ConFlo II interface, which is also used to inject SO2 reference gas and helium for sample dilution. The IRMS is a Thermo Scientific Delta V Plus CF-IRMS. It has a universal triple collector with two wide cups and a narrow cup in the middle. It is capable of measuring mass/charge (m/z) 64 and 66 simultaneously. The ion beams from SO2 are as follows: m/z 64 = SO2 = 32S16O16O; m/z 66 = SO2 = 34S16O16O primarily.
Is Single-Port Laparoscopy More Precise and Faster with the Robot?
Fransen, Sofie A F; van den Bos, Jacqueline; Stassen, Laurents P S; Bouvy, Nicole D
2016-11-01
Single-port laparoscopy is a step forward toward nearly scar less surgery. Concern has been raised that single-incision laparoscopic surgery (SILS) is technically more challenging because of the lack of triangulation and the clashing of instruments. Robotic single-incision laparoscopic surgery (RSILS) in chopstick setting might overcome these problems. This study evaluated the outcome in time and errors of two tasks of the Fundamentals of Laparoscopic Surgery on a dry platform, in two settings: SILS versus RSILS. Nine experienced laparoscopic surgeons performed two tasks: peg transfer and a suturing task, on a standard box trainer. All participants practiced each task three times in both settings: SILS and a RSILS setting. The assessment scores (time and errors) were recorded. For the first task of peg transfer, RSILS was significantly better in time (124 versus 230 seconds, P = .0004) and errors (0.80 errors versus 2.60 errors, P = .024) at the first run, compared to the SILS setting. At the third and final run, RSILS still proved to be significantly better in errors (0.10 errors versus 0.80 errors, P = .025) compared to the SILS group. RSILS was faster in the third run, but not significant (116 versus 157 seconds, P = .08). For the second task, a suturing task, only 3 participants of the SILS group were able to perform this task within the set time frame of 600 seconds. There was no significant difference in time in the three runs between SILS and RSILS for the 3 participants that fulfilled both tasks within the 600 seconds. This study shows that robotic single-port surgery seems easier, faster, and more precise to perform basis tasks of the Fundamentals of laparoscopic surgery. For the more complex task of suturing, only the single-port robotic setting enabled all participants to fulfill this task, within the set time frame.
Determination of the δ34S of sulfate in water; RSIL lab code 1951
Revesz, Kinga; Qi, Haiping; Coplen, Tyler B.
2006-01-01
The purpose of the Reston Stable Isotope Laboratory (RSIL) lab code 1951 is to determine the δ(34S/32S), abbreviated as δ34S, of dissolved sulfate. Dissolved sulfate is collected in the field and precipitated with BaCl2 at pH 3 to 4 as BaSO4 in the laboratory. However, the dissolved organic sulfur (DOS) is oxidized to SO2, and the carbonate is acidified to CO2. Both are degassed from the water sample before the sulfate is precipitated. The precipitated BaSO4 is filtered and dried before introduction into an elemental analyzer (EA) Carlo Erba NC 2500. The EA is used to convert sulfur in a BaSO4 solid sample into SO2 gas, and the EA is connected to a continuous flow isotope-ratio mass spectrometer (CF-IRMS), which determines the differences in the isotope-amount ratios of stable sulfur isotopes (34S/32S) of the product SO2 gas. The combustion is quantitative; no isotopic fractionation is involved. Samples are placed in a tin capsule and loaded into the Costech Zero Blank Autosampler of the EA. Under computer control, samples are dropped into a heated tube reaction tube that combines the oxidation and reduction reactions. The combustion takes place in a helium atmosphere containing an excess of oxygen gas at the oxidation zone at the top of the reaction tube. Combustion products are transported by a helium carrier through the reduction zone at the bottom of the reaction tube to remove excess oxygen and through a separate drying tube to remove any water. The gas-phase products, mainly CO2, N2, and SO2, are separated by a gas chromatograph. The gas is then introduced into the isotope-ratio mass spectrometer (IRMS) through a Finnigan MAT (now Thermo Scientific) ConFlo II interface, which also is used to inject SO2 reference gas and helium for sample dilution. The IRMS is a Thermo Scientific Delta V Plus CF-IRMS. It has a universal triple collector with two wide cups and a narrow cup in the middle. It is capable of measuring mass/charge (m/z) 64 and 66 simultaneously. The ion beams from SO2 are as follows: m/z 64 = SO2 = 32S16O16O; m/z 66 = SO2 = 34S16O16O primarily.
Révész, Kinga M.; Doctor, Daniel H.
2014-01-01
The purposes of the Reston Stable Isotope Laboratory (RSIL) lab codes 1851 and 1852 are to determine the total carbon mass and the ratio of the stable isotopes of carbon (δ13C) for total dissolved inorganic carbon (DIC, lab code 1851) and total nonpurgeable dissolved organic carbon (DOC, lab code 1852) in aqueous samples. The analysis procedure is automated according to a method that utilizes a total carbon analyzer as a peripheral sample preparation device for analysis of carbon dioxide (CO2) gas by a continuous-flow isotope ratio mass spectrometer (CF-IRMS). The carbon analyzer produces CO2 and determines the carbon mass in parts per million (ppm) of DIC and DOC in each sample separately, and the CF-IRMS determines the carbon isotope ratio of the produced CO2. This configuration provides a fully automated analysis of total carbon mass and δ13C with no operator intervention, additional sample preparation, or other manual analysis. To determine the DIC, the carbon analyzer transfers a specified sample volume to a heated (70 °C) reaction vessel with a preprogrammed volume of 10% phosphoric acid (H3PO4), which allows the carbonate and bicarbonate species in the sample to dissociate to CO2. The CO2 from the reacted sample is subsequently purged with a flow of helium gas that sweeps the CO2 through an infrared CO2 detector and quantifies the CO2. The CO2 is then carried through a high-temperature (650 °C) scrubber reactor, a series of water traps, and ultimately to the inlet of the mass spectrometer. For the analysis of total dissolved organic carbon, the carbon analyzer performs a second step on the sample in the heated reaction vessel during which a preprogrammed volume of sodium persulfate (Na2S2O8) is added, and the hydroxyl radicals oxidize the organics to CO2. Samples containing 2 ppm to 30,000 ppm of carbon are analyzed. The precision of the carbon isotope analysis is within 0.3 per mill for DIC, and within 0.5 per mill for DOC.
Determination of the delta(18O/16O)of Water: RSIL Lab Code 489
Revesz, Kinga; Coplen, Tyler
2008-01-01
The purpose of the technique described by the Reston Stable Isotope Laboratory (RSIL) lab code 489 is to present a method to determine the delta(180/160), abbreviated as delta-180, of water. This delta-18O measurement of water also is a component of National Water Quality Laboratory (NWQL in USGS) schedules 1142 and 1172. Water samples are loaded into glass sample containers on a vacuum manifold to equilibrate gaseous CO2 at constant temperature (25 deg C) with water samples. After loading water samples on the vacuum manifold, air is evacuated through capillary to avoid evaporation, and CO2 is added. The samples are shaken to increase the equilibration rate of water and CO2. When isotopic equilibrium has been attained, an aliquot of CO2 is extracted sequentially from each sample container, separated from water vapor by means of a dry ice trap, and introduced into a dual-inlet isotope-ratio mass spectrometer (DI-IRMS) for determination of the delta-18O value. There is oxygen isotopic fractionation between water and CO2, but it is constant at constant temperature. The DI-IRMS is a DuPont double-focusing mass spectrometer. It has a double collector. One ion beam passes through a slit in a forward collector and is collected in the rear collector. The other ion beams are collected in the front collector. The instrument is capable of measuring mass/charge (m/z) 44 and 45 or 44 and 46 by changing the ion-accelerating voltage under computer control. The ion beams from these m/z values are as follows: m/z 44=CO2=12C16O16O, m/z 45=CO2=13C16O16O primarily, and m/z 46 = CO2=12C16O18O primarily. The data acquisition and control software calculates delta-18O values.
Determination of the δ15N of nitrate in water; RSIL lab code 2899
Coplen, Tyler B.; Qi, Haiping; Revesz, Kinga; Casciotti, Karen; Hannon, Janet E.
2007-01-01
The purpose of the Reston Stable Isotope Laboratory (RSIL) lab code 2899 is to determine the δ15N of nitrate (NO3-) in water. The δ15N of the dissolved NO3- is analyzed by conversion of the NO3- to nitrous oxide (N2O), which serves as the analyte for mass spectrometry. A culture of denitrifying bacteria is used in the enzymatic conversion of the NO3- to N2O, which follows the pathway shown in equation 1: NO3- → NO2- → NO → 1/2 N2O (1) Because the bacteria Pseudomonas aureofaciens lack N2O reductive activity, the reaction stops at N2O, unlike the typical denitrification reaction that goes to N2. After several hours, the conversion is complete, and the N2O is extracted from the vial, separated from volatile organic vapor and water vapor by an automated -65 °C isopropanol-slush trap, a Nafion drier, a CO2 and water removal unit (Costech #021020 carbon dioxide absorbent with Mg(ClO4)2), and trapped in a small-volume trap immersed in liquid nitrogen with a modified Finnigan MAT (now Thermo Scientific) GasBench 2 introduction system. After the N2O is released, it is further purified by gas chromatography before introduction to the isotope-ratio mass spectrometer (IRMS). The IRMS is a Thermo Scientific Delta V Plus continuous flow IRMS (CF-IRMS). It has a universal triple collector, consisting of two wide cups with a narrow cup in the middle; it is capable of simultaneously measuring mass/charge (m/z) of the N2O molecule 44, 45, and 46. The ion beams from these m/z values are as follows: m/z = 44 = N2O = 14N14N16O; m/z = 45 = N2O = 14N15N16O or 14N14N17O; m/z = 46 = N2O = 14N14N18O. The 17O contributions to the m/z 44 and m/z 45 ion beams are accounted for before δ15N values are reported.
NASA Technical Reports Server (NTRS)
Dugala, Gina M.; Taylor, Linda M.; Bell, Mark E.; Dolce, James L.; Fraeman, Martin; Frankford, David P.
2015-01-01
NASA Glenn Research Center developed a nonnuclear representation of a Radioisotope Power System (RPS) consisting of a pair of Advanced Stirling Convertors (ASCs), Dual Convertor Controller (DCC) EMs (engineering models) 2 and 3, and associated support equipment, which were tested in the Radioisotope Power Systems System Integration Laboratory (RSIL). The DCC was designed by the Johns Hopkins University Applied Physics Laboratory (JHU/APL) to actively control a pair of ASCs. The first phase of testing included a Dual Advanced Stirling Convertor Simulator (DASCS), which was developed by JHU/APL and simulates the operation and electrical behavior of a pair of ASCs in real time via a combination of hardware and software. RSIL provides insight into the electrical interactions between a representative radioisotope power generator, its associated control schemes, and realistic electric system loads. The first phase of integration testing included the following spacecraft bus configurations: capacitive, battery, and super-capacitor. A load profile, created based on data from several missions, tested the RPS's and RSIL's ability to maintain operation during load demands above and below the power provided by the RPS. The integration testing also confirmed the DCC's ability to disconnect from the spacecraft when the bus voltage dipped below 22 volts or exceeded 36 volts. Once operation was verified with the DASCS, the tests were repeated with actual operating ASCs. The goal of this integration testing was to verify operation of the DCC when connected to a spacecraft and to verify the functionality of the newly designed RSIL. The results of these tests are presented in this paper.
Determination of the δ15N and δ18O of nitrate in water; RSIL lab code 2900
Coplen, Tyler B.; Qi, Haiping; Revesz, Kinga; Casciotti, Karen; Hannon, Janet E.
2007-01-01
The purpose of the Reston Stable Isotope Laboratory (RSIL) lab code 2900 is to determine the δ15N and δ18O of nitrate (NO3-) in water. The δ15N and δ18O of the dissolved NO3- are analyzed by converting the NO3- to nitrous oxide (N2O), which serves as the analyte for mass spectrometry. A culture of denitrifying bacteria is used in the enzymatic conversion of the NO3- to N2O, which follows the pathway shown in equation 1: NO3- → NO2- → NO → 1/2 N2O (1) Because the bacteria Pseudomonas aureofaciens lack N2O reductive activity, the reaction stops at N2O, unlike the typical denitrification reaction that goes to N2. After several hours, the conversion is complete, and the N2O is extracted from the vial, separated from volatile organic vapor and water vapor by an automated -65 °C isopropanol-slush trap, a Nafion drier, a CO2 and water removal unit (Costech #021020 carbon dioxide absorbent with Mg(ClO4)2), and trapped in a small-volume trap immersed in liquid nitrogen with a modified Finnigan MAT (now Thermo Scientific) GasBench 2 introduction system. After the N2O is released, it is further purified by gas chromatography before introduction to the isotope-ratio mass spectrometer (IRMS). The IRMS is a Thermo Scientific Delta V Plus continuous flow IRMS (CF-IRMS). It has a universal triple collector, consisting of two wide cups with a narrow cup in the middle; it is capable of simultaneously measuring mass/charge (m/z) of the N2O molecule 44, 45, and 46. The ion beams from these m/z values are as follows: m/z = 44 = N2O = 14N14N16O; m/z = 45 = N2O = 14N15N16O or 14N14N17O; m/z = 46 = N2O = 14N14N18O. The 17O contributions to the m/z 44 and m/z 45 ion beams are accounted for before δ15N values are reported.
Determination of the delta(15N/14N)of Ammonium (NH4+) in Water: RSIL Lab Code 2898
Hannon, Janet E.; Böhlke, John Karl
2008-01-01
The purpose of the technique described by Reston Stable Isotope Laboratory (RSIL) lab code 2898 is to determine the N isotopic composition, delta(15N/14N), abbreviated as d15N, of ammonium (NH4+) in water (freshwater and saline water). The procedure involves converting dissolved NH4+ into NH3 gas by raising the pH of the sample to above 9 with MgO and subsequently trapping the gas quantitatively as (NH4)2SO4 on a glass fiber (GF) filter. The GF filter is saturated with NaHSO4 and pressure sealed between two gas-permeable polypropylene filters. The GF filter 'sandwich' floats on the surface of the water sample in a closed bottle. NH3 diffuses from the water through the polypropylene filter and reacts with NaHSO4, forming (NH4)2SO4 on the GF filter. The GF filter containing (NH4)2SO4 is dried and then combusted with a Carlo Erba NC 2500 elemental analyzer (EA), which is used to convert total nitrogen in a solid sample into N2 gas. The EA is connected to a continuous-flow isotope-ratio mass spectrometer (CF-IRMS), which determines the relative difference in ratios of the amounts of the stable isotopes of nitrogen (15N and 14N) of the product N2 gas and a reference N2 gas. The filters containing the samples are compressed in tin capsules and loaded into a Costech Zero-Blank Autosampler on the EA. Under computer control, samples then are dropped into a heated reaction tube that contains an oxidant, where combustion takes place in a He atmosphere containing an excess of O2 gas. To remove S-O gases produced from the NaHSO4, a plug of Ag-coated Cu wool is inserted at the bottom of the reaction tube. Combustion products are transported by a He carrier through a reduction furnace to remove excess O2, toconvert all nitrogen oxides to N2, and to remove any remaining S-O gases. The gases then pass through a drying tube to remove water. The gas-phase products, mainly N2 and a small amount of background CO2, are separated by a gas chromatograph (GC). The gas is then introduced into the IRMS through a Finnigan ConFlo II interface. The ConFlo II interface is used to introduce not only sample into the IRMS but also N2 reference gas and He for sample dilution. The flash combustion is quantitative, so no isotopic fractionation is involved. The IRMS is a Finnigan Delta V CF-IRMS with 10 cups and is capable of detecting ion beams with mass/charge (m/z) 28, 29, 30. The ion beams from N2 are as follows: m/z 28 = 14N14N, m/z 29 = 14N15N, and m/z 30 = 15N15N. The ion beam with m/z 30 also represents 14N16O, which may indicate contamination or incomplete reduction.
NASA Technical Reports Server (NTRS)
Dugala, Gina M.; Taylor, Linda M.; Bell, Mark E.; Dolce, James L.; Fraeman, Martin; Frankford, David P.
2015-01-01
NASA Glenn Research Center (GRC) developed a non-nuclear representation of a Radioisotope Power System (RPS) consisting of a pair of Advanced Stirling Convertors (ASC), a Dual Convertor Controller (DCC) EM (engineering model) 2 & 3, and associated support equipment, which were tested in the Radioisotope Power Systems System Integration Laboratory (RSIL). The DCC was designed by the Johns Hopkins University/Applied Physics Laboratory (JHU/APL) to actively control a pair of Advanced Stirling Convertors (ASC). The first phase of testing included a Dual Advanced Stirling Convertor Simulator (DASCS) which was developed by JHU/APL and simulates the operation and electrical behavior of a pair of ASC's in real time via a combination of hardware and software. RSIL provides insight into the electrical interactions between a representative radioisotope power generator, its associated control schemes, and realistic electric system loads. The first phase of integration testing included the following spacecraft bus configurations: capacitive, battery, and supercapacitor. A load profile, created based on data from several missions, tested the RPS and RSIL ability to maintain operation during load demands above and below the power provided by the RPS. The integration testing also confirmed the DCC's ability to disconnect from the spacecraft when the bus voltage dipped below 22 V or exceeded 36 V. Once operation was verified with the DASCS, the tests were repeated with actual operating ASC's. The goal of this integration testing was to verify operation of the DCC when connected to a spacecraft and to verify the functionality of the newly designed RSIL. The results of these tests are presented in this paper.
The Golden Age of Radio: Solid State's Debt to the Rad Lab
NASA Astrophysics Data System (ADS)
Martin, Joseph D.
2011-03-01
While MIT's Radiation Laboratory is rightly celebrated for its contributions to World War II radar research, its legacy extended beyond the war. The Rad Lab provided a model for interdisciplinary collaboration that continued to influence research at MIT in the post-war decades. The Rad Lab's institutional legacy--MIT's interdepartmental laboratories--drove the Institute's postwar research agenda. This talk examines how solid state physics research at MIT was shaped by a laboratory structure that encouraged cross-disciplinary collaboration. As the sub-discipline of solid state physics emerged through the late-1940s and 1950s, MIT was unique among universities in its laboratory structure, made possible by a large degree of government and military funding. Nonetheless, the manner in which MIT research groups from physics, chemistry, engineering, and metallurgy interfaced through the medium of solid state physics exemplified how the discipline of solid state physics came to be structured in the rest of the country. Through examining the Rad Lab's institutional legacy, I argue that World War II radar research, by establishing precedent for a particular mode of interdisciplinary collaboration, shaped the future structure of solid state research in the United States. Research supported by a grant-in-aid from the Friends of the Center for the History of Physics, American Institute of Physics.
Automated, Ultra-Sterile Solid Sample Handling and Analysis on a Chip
NASA Technical Reports Server (NTRS)
Mora, Maria F.; Stockton, Amanda M.; Willis, Peter A.
2013-01-01
There are no existing ultra-sterile lab-on-a-chip systems that can accept solid samples and perform complete chemical analyses without human intervention. The proposed solution is to demonstrate completely automated lab-on-a-chip manipulation of powdered solid samples, followed by on-chip liquid extraction and chemical analysis. This technology utilizes a newly invented glass micro-device for solid manipulation, which mates with existing lab-on-a-chip instrumentation. Devices are fabricated in a Class 10 cleanroom at the JPL MicroDevices Lab, and are plasma-cleaned before and after assembly. Solid samples enter the device through a drilled hole in the top. Existing micro-pumping technology is used to transfer milligrams of powdered sample into an extraction chamber where it is mixed with liquids to extract organic material. Subsequent chemical analysis is performed using portable microchip capillary electrophoresis systems (CE). These instruments have been used for ultra-highly sensitive (parts-per-trillion, pptr) analysis of organic compounds including amines, amino acids, aldehydes, ketones, carboxylic acids, and thiols. Fully autonomous amino acid analyses in liquids were demonstrated; however, to date there have been no reports of completely automated analysis of solid samples on chip. This approach utilizes an existing portable instrument that houses optics, high-voltage power supplies, and solenoids for fully autonomous microfluidic sample processing and CE analysis with laser-induced fluorescence (LIF) detection. Furthermore, the entire system can be sterilized and placed in a cleanroom environment for analyzing samples returned from extraterrestrial targets, if desired. This is an entirely new capability never demonstrated before. The ability to manipulate solid samples, coupled with lab-on-a-chip analysis technology, will enable ultraclean and ultrasensitive end-to-end analysis of samples that is orders of magnitude more sensitive than the ppb goal given in the Science Instruments.
1981-09-15
DISCRIMINATING ELEMENTS OF AN UNDERWATER TOWED ARRAY rsil RONALD A. WAGSTAFF and PIETRO MANASCA D TIC": L• ’" .... 4"•’.,, 15 SEPTEMBER 1981...IMPROVEMENT RESULTING FROM LEFT/RIGHT DISCRIMINATING ELEMENTS OF AN UNDERWATER TOWED ARRAY by Ronald A. Wagstaff and Pietro Zanasca 15 September 1981 F...RESULTING FROM LEFT/RIGHT DISCRIMINATING ELEMENTS OF AN UNDERWATER TOWED ARRAY by Ronald A. Wagstaff and Pietro Zanasca ABSTRACT The improvement in
Code of Federal Regulations, 2013 CFR
2013-07-01
... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. IV Appendix IV to Part 268—Wastes Excluded From Lab Packs Under the Alternative Treatment... 40 Protection of Environment 28 2013-07-01 2013-07-01 false Wastes Excluded From Lab Packs Under...
Code of Federal Regulations, 2012 CFR
2012-07-01
... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. IV Appendix IV to Part 268—Wastes Excluded From Lab Packs Under the Alternative Treatment... 40 Protection of Environment 28 2012-07-01 2012-07-01 false Wastes Excluded From Lab Packs Under...
Code of Federal Regulations, 2011 CFR
2011-07-01
... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. IV Appendix IV to Part 268—Wastes Excluded From Lab Packs Under the Alternative Treatment... 40 Protection of Environment 27 2011-07-01 2011-07-01 false Wastes Excluded From Lab Packs Under...
Code of Federal Regulations, 2010 CFR
2010-07-01
... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. IV Appendix IV to Part 268—Wastes Excluded From Lab Packs Under the Alternative Treatment... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Wastes Excluded From Lab Packs Under...
Code of Federal Regulations, 2014 CFR
2014-07-01
... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. IV Appendix IV to Part 268—Wastes Excluded From Lab Packs Under the Alternative Treatment... 40 Protection of Environment 27 2014-07-01 2014-07-01 false Wastes Excluded From Lab Packs Under...
Unveiling the nucleon tensor charge at Jefferson Lab: A study of the SoLID case
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ye, Zhihong; Sato, Nobuo; Allada, Kalyan
© 2017 The Authors Future experiments at the Jefferson Lab 12 GeV upgrade, in particular, the Solenoidal Large Intensity Device (SoLID), aim at a very precise data set in the region where the partonic structure of the nucleon is dominated by the valence quarks. One of the main goals is to constrain the quark transversity distributions. We apply recent theoretical advances of the global QCD extraction of the transversity distributions to study the impact of future experimental data from the SoLID experiments. Especially, we develop a simple strategy based on the Hessian matrix analysis that allows one to estimate themore » uncertainties of the transversity quark distributions and their tensor charges extracted from SoLID data simulation. We find that the SoLID measurements with the proton and the effective neutron targets can improve the precision of the u- and d-quark transversity distributions up to one order of magnitude in the range 0.05 < x < 0.6.« less
Unveiling the nucleon tensor charge at Jefferson Lab: A study of the SoLID case
NASA Astrophysics Data System (ADS)
Ye, Zhihong; Sato, Nobuo; Allada, Kalyan; Liu, Tianbo; Chen, Jian-Ping; Gao, Haiyan; Kang, Zhong-Bo; Prokudin, Alexei; Sun, Peng; Yuan, Feng
2017-04-01
Future experiments at the Jefferson Lab 12 GeV upgrade, in particular, the Solenoidal Large Intensity Device (SoLID), aim at a very precise data set in the region where the partonic structure of the nucleon is dominated by the valence quarks. One of the main goals is to constrain the quark transversity distributions. We apply recent theoretical advances of the global QCD extraction of the transversity distributions to study the impact of future experimental data from the SoLID experiments. Especially, we develop a simple strategy based on the Hessian matrix analysis that allows one to estimate the uncertainties of the transversity quark distributions and their tensor charges extracted from SoLID data simulation. We find that the SoLID measurements with the proton and the effective neutron targets can improve the precision of the u- and d-quark transversity distributions up to one order of magnitude in the range 0.05 < x < 0.6.
Lauer, Matthias E; Maurer, Reto; Paepe, Anne T De; Stillhart, Cordula; Jacob, Laurence; James, Rajesh; Kojima, Yuki; Rietmann, Rene; Kissling, Tom; van den Ende, Joost A; Schwarz, Sabine; Grassmann, Olaf; Page, Susanne
2018-05-19
Hot-melt extrusion is an option to fabricate amorphous solid dispersions and to enhance oral bioavailability of poorly soluble compounds. The selection of suitable polymer carriers and processing aids determines the dissolution, homogeneity and stability performance of this solid dosage form. A miniaturized extrusion device (MinEx) was developed and Hypromellose acetate succinate type L (HPMCAS-L) based extrudates containing the model drugs neurokinin-1 (NK1) and cholesterylester transfer protein (CETP) were manufactured, plasticizers were added and their impact on dissolution and solid-state properties were assessed. Similar mixtures were manufactured with a lab-scale extruder, for face to face comparison. The properties of MinEx extrudates widely translated to those manufactured with a lab-scale extruder. Plasticizers, Polyethyleneglycol 4000 (PEG4000) and Poloxamer 188, were homogenously distributed but decreased the storage stability of the extrudates. Stearic acid was found condensed in ultrathin nanoplatelets which did not impact the storage stability of the system. Depending on their distribution and physicochemical properties, plasticizers can modulate storage stability and dissolution performance of extrudates. MinEx is a valuable prototyping-screening method and enables rational selection of plasticizers in a time and material sparing manner. In eight out of eight cases the properties of the extrudates translated to products manufactured in lab-scale extrusion trials.
NanoRelease: Pilot interlaboratory comparison of a ...
A major use of multi-walled carbon nanotubes (MWCNTs) is as functional fillers embedded in a solid matrix, such as plastics or coatings. Weathering and abrasion of the solid matrix during use can lead to environmental releases of the MWCNTs. Here we focus on a protocol to identify and quantify the primary release induced by weathering, and assess reproducibility, transferability, and sensitivity towards different materials and uses. We prepared 132 specimens of two polymer-MWCNT composites containing the same grade of MWCNTs used in earlier OECD hazard assessments but without UV stabilizer. We report on a pilot inter-laboratory comparison (ILC) with four labs (two US and two EU) aging by UV and rain, then shipping for analysis. Two labs (one US and one EU) conducted the release sampling and analysis by Transmission Electron Microscopy (TEM), Inductively Coupled Plasma- Mass Spectrometry (ICP-MS), Ultraviolet–Visible Spectroscopy (UV–Vis), Analytical Ultracentrifugation (AUC), and Asymmetric Flow Field Flow Fractionation (AF4). We compare results between aging labs, between analysis labs and between materials. Surprisingly, we found quantitative agreement between analysis labs for TEM, ICP-MS, UV–Vis; low variation between aging labs by all methods; and consistent rankings of release between TEM, ICP-MS, UV–Vis, AUC. Significant disagreement was related primarily to differences in aging, but even these cases remained within a factor of two. Published in t
NASA Technical Reports Server (NTRS)
Dugala, Gina M.; Taylor, Linda M.; Kussmaul, Michael; Casciani, Michael; Brown, Gregory; Wiser, Joel
2017-01-01
Future NASA missions could include establishing Lunar or Martian base camps, exploring Jupiters moons and travelling beyond where generating power from sunlight may be limited. Radioisotope Power Systems (RPS) provide a dependable power source for missions where inadequate sunlight or operational requirements make other power systems impractical. Over the past decade, NASA Glenn Research Center (GRC) has been supporting the development of RPSs. The Advanced Stirling Radioisotope Generator (ASRG) utilized a pair of Advanced Stirling Convertors (ASC). While flight development of the ASRG has been cancelled, much of the technology and hardware continued development and testing to guide future activities. Specifically, a controller for the convertor(s) is an integral part of a Stirling-based RPS. For the ASRG design, the controller maintains stable operation of the convertors, regulates the alternating current produced by the linear alternator of the convertor, provides a specified direct current output voltage for the spacecraft, synchronizes the piston motion of the two convertors in order to minimize vibration as well as manage and maintain operation with a stable piston amplitude and hot end temperature. It not only provides power to the spacecraft but also must regulate convertor operation to avoid damage to internal components and maintain safe thermal conditions after fueling. Lockheed Martin Coherent Technologies has designed, developed and tested an Engineering Development Unit (EDU) Advanced Stirling Convertor Control Unit (ACU) to support this effort. GRC used the ACU EDU as part of its non-nuclear representation of a RPS which also consists of a pair of Dual Advanced Stirling Convertor Simulator (DASCS), and associated support equipment to perform a test in the Radioisotope Power Systems System Integration Laboratory (RSIL). The RSIL was designed and built to evaluate hardware utilizing RPS technology. The RSIL provides insight into the electrical interactions between as many as 3 radioisotope power generators, associated control strategies, and typical electric system loads. The first phase of testing included a DASCS which was developed by Johns Hopkins UniversityApplied Physics Laboratory and simulates the operation and electrical behavior of a pair of ASCs in real time via a combination of hardware and software. Testing included the following spacecraft electrical energy storage configurations: capacitive, battery, and supercapacitor. Testing of the DASCS and ACU in each energy storage configuration included simulation of a typical mission profile, and transient voltage and current data during load turn-on/turn-off. Testing for these devices also included the initiation of several system faults such as short circuits, electrical bus over-voltage, under-voltage and a dead bus recovery to restore normal power operations. The goal of this testing was to verify operation of the ACU(s) when connected to a spacecraft electrical bus.
Behavior of TiO₂ nanoparticles during incineration of solid paint waste: a lab-scale test.
Massari, Andrea; Beggio, Marta; Hreglich, Sandro; Marin, Riccardo; Zuin, Stefano
2014-10-01
In order to assess the potential impacts posed by products containing engineered nanoparticles, it is essential to generate more data about the release of these particles from products' life cycle. Although first studies were performed to investigate the release of nanoparticles from use phase, very few data are available on the potential release from recycling or disposal of nano-enhanced products. In this work, we investigated the behavior of TiO2 nanoparticles from incineration of solid paint waste containing these particles. Solid paint debris with and without TiO2 nanoparticles were treated in a lab scale incineration plant at 950°C (combustion temperature) and in oxidizing atmosphere. The obtained ashes were also vitrified with additives and the release of Ti was finally evaluated by leaching test. From our incineration lab-scale experiment, we did not observe a release of TiO2 nanoparticles into the atmosphere, and Ti was attached to the surface of obtained solid residues (i.e. ashes). The characterization of ashes showed that TiO2 nanoparticles reacted during the incineration to give calcium titanate. Finally, a very low release of Ti was measured, less 1 mg/kg, during the leaching test of ashes vitrified with glass cullet and feldspathic inert. Our work suggests that TiO2 nanoparticles added in paints may undergo to physicochemical transformation during the incineration, and that Ti found in ashes may be strongly immobilized in glass matrix. Since this conclusion is based on lab-scale experiment, further research is required to identify which nanoparticles will be emitted to the environment from a real-word-incineration system of household hazardous waste. Copyright © 2014 Elsevier Ltd. All rights reserved.
Petigny, Loïc; Périno, Sandrine; Minuti, Matteo; Visinoni, Francesco; Wajsman, Joël; Chemat, Farid
2014-01-01
Microwave extraction and separation has been used to increase the concentration of the extract compared to the conventional method with the same solid/liquid ratio, reducing extraction time and separate at the same time Volatile Organic Compounds (VOC) from non-Volatile Organic Compounds (NVOC) of boldo leaves. As preliminary study, a response surface method has been used to optimize the extraction of soluble material and the separation of VOC from the plant in laboratory scale. The results from the statistical analysis revealed that the optimized conditions were: microwave power 200 W, extraction time 56 min and solid liquid ratio of 7.5% of plants in water. Lab scale optimized microwave method is compared to conventional distillation, and requires a power/mass ratio of 0.4 W/g of water engaged. This power/mass ratio is kept in order to upscale from lab to pilot plant. PMID:24776762
Guo, Y X; Han, J; Zhang, D Y; Wang, L H; Zhou, L L
2012-07-01
We studied the effect of ultrasonication extraction technology combined with ammonium sulfate/ethanol aqueous two-phase system (ATPS) for the separation of lithospermic acid B (LAB) from Salvia miltiorrhiza Bunge. According to the literature and preliminary studies, ammonium sulfate concentration, ethanol concentration, pH, ultrasonication power, ultrasonication time and the ratio of solvent-to-solid were investigated using a single factor design to identify the factors affecting separation. Taking into consideration a simultaneous increase in LAB recovery (R (%)) and partition coefficient (K), the best performance of the ATPS was obtained at 25°C and pH 2 using ammonium sulfate 22% (w/w) and ethanol 30% (w/w). To keep the solvent-to-solid ratio at 10, response surface methodology was used to find the optimal ultrasonication power and ultrasonication time. Quadratic models were predicted for LAB yield in the upper phase. Optimal conditions of 572.1 W ultrasonication power and 42.2 min produced a maximum yield of LAB of 42.16 mg g(-1) sample. There was no obvious degradation of LAB with ultrasound under the applied conditions, and the experimental yield of LAB was 42.49 mg g(-1) sample and the purity was 55.28% (w/w), which was much higher than that obtained using conventional extraction. The present study demonstrated that ultrasound coupled with aqueous two-phase systems is very efficient tool for the extraction and purification of LAB from Salvia miltiorrhiza Bunge. Copyright © 2011 Elsevier B.V. All rights reserved.
Perspectives on Industrial Innovation from Agilent, HP, and Bell Labs
NASA Astrophysics Data System (ADS)
Hollenhorst, James
2014-03-01
Innovation is the life blood of technology companies. I will give perspectives gleaned from a career in research and development at Bell Labs, HP Labs, and Agilent Labs, from the point of view of an individual contributor and a manager. Physicists bring a unique set of skills to the corporate environment, including a desire to understand the fundamentals, a solid foundation in physical principles, expertise in applied mathematics, and most importantly, an attitude: namely, that hard problems can be solved by breaking them into manageable pieces. In my experience, hiring managers in industry seldom explicitly search for physicists, but they want people with those skills.
Pérez-Cataluña, Alba; Elizaquível, Patricia; Carrasco, Purificación; Espinosa, Judith; Reyes, Dolores; Wacher, Carmen; Aznar, Rosa
2018-03-01
The purpose of this work was to analyse the diversity and dynamics of lactic acid bacteria (LAB) throughout the fermentation process in Atole agrio, a traditional maize based food of Mexican origin. Samples of different fermentation times were analysed using culture-dependent and -independent approaches. Identification of LAB isolates revealed the presence of members of the genera Pediococcus, Weissella, Lactobacillus, Leuconostoc and Lactococcus, and the predominance of Pediococcus pentosaceus and Weissella confusa in liquid and solid batches, respectively. High-throughput sequencing (HTS) of the 16S rRNA gene confirmed the predominance of Lactobacillaceae and Leuconostocaceae at the beginning of the process. In liquid fermentation Acetobacteraceae dominate after 4 h as pH decreased. In contrast, Leuconostocaceae dominated the solid fermentation except at 12 h that were overgrown by Acetobacteraceae. Regarding LAB genera, Lactobacillus dominated the liquid fermentation except at 12 h when Weissella, Lactococcus and Streptococcus were the most abundant. In solid fermentation Weissella predominated all through the process. HTS determined that Lactobacillus plantarum and W. confusa dominated in the liquid and solid batches, respectively. Two oligotypes have been identified for L. plantarum and W. confusa populations, differing in a single nucleotide position each. Only one of the oligotypes was detected among the isolates obtained from each species, the biological significance of which remains unclear.
Elman, Noel M; Ben-Yoav, Hadar; Sternheim, Marek; Rosen, Rachel; Krylov, Slava; Shacham-Diamand, Yosi
2008-06-15
A lab-on-chip consisting of a unique integration of whole-cell sensors, a MOEMS (Micro-Opto-Electro-Mechanical-System) modulator, and solid-state photo-detectors was implemented for the first time. Whole-cell sensors were genetically engineered to express a bioluminescent reporter (lux) as a function of the lac promoter. The MOEMS modulator was designed to overcome the inherent low frequency noise of solid-state photo-detectors by means of a previously reported modulation technique, named IHOS (Integrated Heterodyne Optical System). The bio-reporter signals were modulated prior to photo-detection, increasing the SNR of solid-state photo-detectors at least by three orders of magnitude. Experiments were performed using isopropyl-beta-d-thiogalactopyranoside (IPTG) as a preliminary step towards testing environmental toxicity. The inducer was used to trigger the expression response of the whole-cell sensors testing the sensitivity of the lab-on-chip. Low intensity bio-reporter optical signals were measured after the whole-cell sensors were exposed to IPTG concentrations of 0.1, 0.05, and 0.02mM. The experimental results reveal the potential of this technology for future implementation as an inexpensive massive method for rapid environmental toxicity detection.
ERIC Educational Resources Information Center
Xu, Xinhua; Wang, Xiaogang; Wu, Meifen
2014-01-01
The determination of the solid-liquid phase diagram of a binary system is always used as an experiment in the undergraduate physical chemistry laboratory courses. However, most phase diagrams investigated in the lab are simple eutectic ones, despite the fact that complex binary solid-liquid phase diagrams are more common. In this article, the…
Unveiling the nucleon tensor charge at Jefferson Lab: A study of the SoLID case
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ye, Zhihong; Sato, Nobuo; Allada, Kalyan
2017-01-27
Here, future experiments at the Jefferson Lab 12 GeV upgrade, in particular, the Solenoidal Large Intensity Device (SoLID), aim at a very precise data set in the region where the partonic structure of the nucleon is dominated by the valence quarks. One of the main goals is to constrain the transversity quark distributions. We apply recent theoretical advances of the global QCD extraction of the transversity distributions to study the impact of future experimental data from the SoLID. Especially, we develop a model-independent method based on the hessian matrix analysis that allows to estimate the uncertainties of the transversity quarkmore » distributions and their tensor charge contributions extracted from the pseudo-data for the SoLID. Both u and d-quark transversity distributions are shown to be very well constrained in the kinematical region of the future experiments with the proton and the effective neutron targets.« less
Quantifying fat, oil, and grease deposit formation kinetics
USDA-ARS?s Scientific Manuscript database
Fat, oil, and grease (FOG) deposits formed in sanitary sewers are calcium-based saponified solids that are responsible for a significant number of nationwide sanitary sewer overflows (SSOs) across United States. In the current study, the kinetics of lab-based saponified solids were determined to un...
A Microwave-Assisted Reduction of Cyclohexanone Using Solid-State-Supported Sodium Borohydride
ERIC Educational Resources Information Center
White, Lori L.; Kittredge, Kevin W.
2005-01-01
The reduction of carbonyl groups by sodium borohydride though is a well-known reaction in most organic lab texts, a difficulty for an instructor adopting this reaction in a student lab is that it is too long. Using a microwave assisted organic synthesis solves this difficulty and one such reaction, which is the microwave-assisted reduction of…
ERIC Educational Resources Information Center
Naviglio, Daniele; Montesano, Domenico; Gallo, Monica
2015-01-01
Two experimental techniques of solid-liquid extraction are compared relating to the lab-scale production of lemon liqueur, most commonly named "limoncello"; the first is the official method of maceration for the solid-liquid extraction of analytes and is widely used to extract active ingredients from a great variety of natural products;…
Katoh, Masakazu; Hamajima, Fumiyasu; Ogasawara, Takahiro; Hata, Ken-ichiro
2013-12-01
Finding in vitro eye irritation testing alternatives to animal testing such as the Draize eye test, which uses rabbits, is essential from the standpoint of animal welfare. It has been developed a reconstructed human corneal epithelial model, the LabCyte CORNEA-MODEL, which has a representative corneal epithelium-like structure. Protocol optimization (pre-validation study) was examined in order to establish a new alternative method for eye irritancy evaluation with this model. From the results of the optimization experiments, the application periods for chemicals were set at 1min for liquid chemicals or 24h for solid chemicals, and the post-exposure incubation periods were set at 24h for liquids or zero for solids. If the viability was less than 50%, the chemical was judged to be an eye irritant. Sixty-one chemicals were applied in the optimized protocol using the LabCyte CORNEA-MODEL and these results were evaluated in correlation with in vivo results. The predictions of the optimized LabCyte CORNEA-MODEL eye irritation test methods were highly correlated with in vivo eye irritation (sensitivity 100%, specificity 80.0%, and accuracy 91.8%). These results suggest that the LabCyte CORNEA-MODEL eye irritation test could be useful as an alternative method to the Draize eye test. Copyright © 2013 Elsevier Ltd. All rights reserved.
Determination of the δ2H and δ18O of soil water and water in plant matter; RSIL lab code 1700
Revesz, Kinga M.; Buck, Bryan; Coplen, Tyler B.
2012-01-01
The purpose of the Reston Stable Isotope Laboratory lab code 1700 is to determine the δ2H/1H), abbreviated as δ2H, and the δ18O/16O), abbreviated as δ18O, of soil water and water in plant matter. This method is based on the observation that water and toluene form an azeotropic mixture at 84.1 °C. This temperature is substantially lower than the boiling points of water (100 °C) and toluene (110 °C), but water and toluene are immiscible at ambient temperature. The water content of a soil or plant is determined by weighing, drying, and reweighing a small amount of sample. Sufficient sample to collect 3 to 5 milliliters of water after distillation is loaded into a distillation flask. Sufficient toluene is added so that the sample is immersed throughout the entire distillation to minimize evaporation of water, which would affect the δ2H and δ18O values. The mixture of sample and toluene is heated in a flask to its boiling point (84.1 °C) so that water from the sample and toluene can distill together into a specially designed collection funnel. The temperature of 84.1 °C is maintained until the water has been quantitatively transferred to the collection funnel, at which time the temperature is raised to the boiling point of the remaining component (toluene, 110 °C). The collection funnel is maintained at ambient temperature so that the sample water and toluene can be separated physically. After separation, the sample water is purified by addition of paraffin wax to the container with the sample water, capping the container, and heating to approximately 60 °C to melt the wax. Trace amounts of toluene will dissolve in the wax, purifying the sample water for isotopic analysis. The isotopic composition of the purified water is then determined by equilibration with gaseous hydrogen or carbon dioxide, followed by dual-inlet isotope-ratio mass spectrometry. Because laser-absorption spectrometry is sensitive to organic compounds, such as trace toluene remaining in water samples, water samples should be analyzed for isotopic composition only by mass spectrometry and not by laser-absorption spectrometry.
Nie, Zhiqiang; Zheng, Yu; Wang, Min; Han, Yue; Wang, Yuenan; Luo, Jianmei; Niu, Dandan
2013-11-01
Tianjin duliu mature vinegar was one of famous Chinese traditional vinegars. The unique flavor and taste of vinegar are mainly generated by the multitudinous microorganisms during fermentation. In this research, the composition and succession of microbial communities in the entire solid-state fermentation were investigated, including starter daqu and acetic acid fermentation (AAF). Molds and yeasts in daqu, including Aspergillus, Saccharomycopsis and Pichia, decreased in AAF. The bacterial compositions increased from four genera in daqu to more than 13 genera in AAF. Principal component analysis showed that Acetobacter, Gluconacetobacter, Lactobacillus and Nostoc were dominant bacteria that were correlated well with AAF process. In the early fermentation period, lactic acid bacteria (LAB) decreased while acetic acid bacteria and Nostoc increased rapidly with the accumulation of total acids. Then, the abundance and diversity of LAB increased (more than 80%), indicating that LAB had important influences on the flavor and taste of vinegar. Copyright © 2013 Elsevier Ltd. All rights reserved.
The LabTube - a novel microfluidic platform for assay automation in laboratory centrifuges.
Kloke, A; Fiebach, A R; Zhang, S; Drechsel, L; Niekrawietz, S; Hoehl, M M; Kneusel, R; Panthel, K; Steigert, J; von Stetten, F; Zengerle, R; Paust, N
2014-05-07
Assay automation is the key for successful transformation of modern biotechnology into routine workflows. Yet, it requires considerable investment in processing devices and auxiliary infrastructure, which is not cost-efficient for laboratories with low or medium sample throughput or point-of-care testing. To close this gap, we present the LabTube platform, which is based on assay specific disposable cartridges for processing in laboratory centrifuges. LabTube cartridges comprise interfaces for sample loading and downstream applications and fluidic unit operations for release of prestored reagents, mixing, and solid phase extraction. Process control is achieved by a centrifugally-actuated ballpen mechanism. To demonstrate the workflow and functionality of the LabTube platform, we show two LabTube automated sample preparation assays from laboratory routines: DNA extractions from whole blood and purification of His-tagged proteins. Equal DNA and protein yields were observed compared to manual reference runs, while LabTube automation could significantly reduce the hands-on-time to one minute per extraction.
Wide-field Imaging System and Rapid Direction of Optical Zoom (WOZ)
2010-09-25
commercial software packages: SolidWorks, COMSOL Multiphysics, and ZEMAX optical design. SolidWorks is a computer aided design package, which as a live...interface to COMSOL. COMSOL is a finite element analysis/partial differential equation solver. ZEMAX is an optical design package. Both COMSOL and... ZEMAX have live interfaces to MatLab. Our initial investigations have enabled a model in SolidWorks to be updated in COMSOL, an FEA calculation
Credit PSR. View looks west southwest (238°) at the north ...
Credit PSR. View looks west southwest (238°) at the north and east elevations of the liner lab. Solid rocket motor casings receive specially formulated rubber insulating liners that protect the casings from the heat generated by burning solid motors - Jet Propulsion Laboratory Edwards Facility, Liner Laboratory, Edwards Air Force Base, Boron, Kern County, CA
Selected KSC Applied Physics Lab Responses to Shuttle Processing Measurement Requests
NASA Technical Reports Server (NTRS)
Youngquist, Robert C.
2010-01-01
The KSC Applied Physics Lab has been supporting Shuttle Ground Processing for over 20 years by solving problems brought to us by Shuttle personnel. Roughly half of the requests to our lab have been to find ways to make measurements, or to improve on an existing measurement process. This talk will briefly cover: 1) Centering the aft end of the External Tank between the Solid Rocket Boosters; 2) Positioning the GOX Vent Hood over the External Tank; 3) Remote Measurements of External Tank Damage; 4) Strain Measurement in the Orbiter Sling; and 5) Over-center Distance Measurement in an Over-center Mechanism.
Phase Field Fracture Mechanics.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robertson, Brett Anthony
For this assignment, a newer technique of fracture mechanics using a phase field approach, will be examined and compared with experimental data for a bend test and a tension test. The software being used is Sierra Solid Mechanics, an implicit/explicit finite element code developed at Sandia National Labs in Albuquerque, New Mexico. The bend test experimental data was also obtained at Sandia Labs while the tension test data was found in a report online from Purdue University.
Rodríguez, Rogelio; Avivar, Jessica; Ferrer, Laura; Leal, Luz O; Cerdà, Victor
2012-07-15
A novel lab-on-valve system has been developed for strontium determination in environmental samples. Miniaturized lab-on-valve system potentially offers facilities to allow any kind of chemical and physical processes, including fluidic and microcarrier bead control, homogenous reaction and liquid-solid interaction. A rapid, inexpensive and fully automated method for the separation and preconcentration of total and radioactive strontium, using a solid phase extraction material (Sr-Resin), has been developed. Total strontium concentrations are determined by ICP-OES and (90)Sr activities by a low background proportional counter. The method has been successfully applied to different water samples of environmental interest. The proposed system offers minimization of sample handling, drastic reduction of reagent volume, improvement of the reproducibility and sample throughput and attains a significant decrease of both time and cost per analysis. The LLD of the total Sr reached is 1.8ng and the minimum detectable activity for (90)Sr is 0.008Bq. The repeatability of the separation procedure is 1.2% (n=10). Copyright © 2011 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Ma, Yan-Zi; Jia, Li; Ma, Kai-Guo; Wang, Hai-Hong; Jing, Xi-Ping
2017-01-01
An integrated and inquiry-based experiment on solid state chemistry is applied to an inorganic chemistry lab course to provide insight into the characteristics of the solid phase reaction. In this experiment, students have the opportunity to synthesize long-lasting phosphors with formula xSrO·yAl[subscript 2]O[subscript 3]:Eu[superscript 2+],…
Bartkiene, Elena; Krungleviciute, Vita; Juodeikiene, Grazina; Vidmantiene, Daiva; Maknickiene, Zita
2015-04-01
The ability of bacteriocin-like inhibitory substance (BLIS)-producing lactic acid bacteria (LAB) to degrade biogenic amines as well as to produce L(+) and D(-)-lactic acid during solid state fermentation (SSF) of lupin and soya bean was investigated. In addition, the protein digestibility and formation of organic acids during SSF of legume were investigated. Protein digestibility of fermented lupin and soya bean was found higher on average by 18.3% and 15.9%, respectively, compared to untreated samples. Tested LAB produced mainly L-lactic acid in soya bean and lupin (D/L ratio 0.38-0.42 and 0.35-0.54, respectively), while spontaneous fermentation gave almost equal amounts of both lactic acid isomers (D/L ratio 0.82-0.98 and 0.92, respectively). Tested LAB strains were able to degrade phenylethylamine, spermine and spermidine, whereas they were able to produce putrescine, histamine and tyramine. SSF improved lupin and soya bean protein digestibility. BLIS-producing LAB in lupin and soya bean medium produced a mixture of D- and L-lactic acid with a major excess of the latter isomer. Most toxic histamine and tyramine in fermented lupin and soya bean were found at levels lower those causing adverse health effects. Selection of biogenic amines non-producing bacteria is essential in the food industry to avoid the risk of amine formation. © 2014 Society of Chemical Industry.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Winters, M.S.; McElheny, G.; Houston, L.M.
2013-07-01
A case study is presented on specific program elements that supported the transition of a temporary field radiological screening lab to an accredited operation capable of meeting client quality objectives for definitive results data. The temporary field lab is located at the Formerly Utilized Sites Remedial Action Program Linde Site in Tonawanda, NY. The site is undergoing remediation under the direction of the United States Army Corps of Engineers - Buffalo District, with Cabrera Services Inc. as the remediation contractor and operator of the on-site lab. Analysis methods employed in the on-site lab include gross counting of alpha and betamore » particle activity on swipes and air filters and gamma spectroscopy of soils and other solid samples. A discussion of key program elements and lessons learned may help other organizations considering pursuit of accreditation for on-site screening laboratories. (authors)« less
Maiorchino Cheese: Physico-Chemical, Hygienic and Safety Characteristics
Ravidà, Andrea; Mandanici, Alessandro; Ferrantelli, Vincenzo; Chetta, Michele; Verzera, Antonella
2015-01-01
This study assessed the physical, chemical, and microbiological characteristics of traditional Maiorchino cheese (Italy) made from raw ewe’s milk or from a mixture with goat’s milk. Cheese samples from the same batch were analyzed after 20 days and 6, 8, 12, 17 and 24 months of ripening. A decrease in moisture level lead to progressive total solids concentration (fat, total nitrogen, total solids and chloride) during ripening. Aw values decreased from 0.97 (day 20) to 0.85 (month 24), while pH increased from 4.99 to 5.41 (6 months) followed a by reduction until 4.85 (month 24). In samples analysed 20 days after cheesemaking, aerobic mesophilic count was 1.8•107 CFU/g, Enterobacteriaceae were 2.7•106 CFU/g, Staphylococcus spp. were 1.8•104 CFU/g, and yeasts 4.5•105 CFU/g. Sulphite reducing bacteria were not found. Lactic bacteria count at 30°C (LAB30) and 42°C (LAB42) was about 108 CFU/g (day 20); LAB30 reduced until month 8; LAB 42 reduced until month 12; both were not detectable at months 17 and 24. Cheese-making process does not consider commercial starter cultures and LAB group is heterogeneous because of its natural microflora. Yeasts were considered as typical microflora of Maiorchino. Volatile compounds were examined at 6, 12 and 24 months of ripening; 54 components were identified. Statistical analysis showed that the seasoning period of 12 months was the best for Maiorchino flavour attributes. The characterisation of Maiorchino traditional cheese may be considered as significant for this old traditional product, with the aim of obtaining the PDO certification. PMID:27800379
NASA Technical Reports Server (NTRS)
Chavez, Patrick F.
1987-01-01
The effort at Sandia National Labs. on the methodologies and techniques being used to generate strict hexahedral finite element meshes from a solid model is described. The functionality of the modeler is used to decompose the solid into a set of nonintersecting meshable finite element primitives. The description of the decomposition is exported, via a Boundary Representative format, to the meshing program which uses the information for complete finite element model specification. Particular features of the program are discussed in some detail along with future plans for development which includes automation of the decomposition using artificial intelligence techniques.
Cao, Wenlong; Vaddella, Venkata; Biswas, Sagor; Perkins, Katherine; Clay, Cameron; Wu, Tong; Zheng, Yawen; Ndegwa, Pius; Pandey, Pramod
2016-11-01
Vermicomposting (VC) has proven to be a promising method for treating garden, household, and municipal wastes. Although the VC has been used extensively for converting wastes into fertilizers, pathogens such as Escherichia coli (E. coli) survival during this process is not well documented. In this study, both lab and field scale experiments were conducted assessing the impacts of earthworms in reducing E. coli concentration during VC of food waste. In addition, other pertinent parameters such as temperature, carbon and nitrogen content, moisture content, pH, volatile solids, micronutrients (P, K, Ca, Mg, and S), and heavy metals (Zn, Mn, Fe, and Cu) were monitored during the study. The lab and field scale experiments were conducted for 107 and 103 days, respectively. The carbon to nitrogen ratio (C/N) decreased by 54 % in the lab scale study and by 36 % in the field study. Results showed that VC was not significantly effective in reducing E. coli levels in food waste under both lab and field scale settings. The carbon to nitrogen ratio (C/N) decreased by 54 % in the lab scale study and by 36 % in the field study.
Towards lactic acid bacteria-based biorefineries.
Mazzoli, Roberto; Bosco, Francesca; Mizrahi, Itzhak; Bayer, Edward A; Pessione, Enrica
2014-11-15
Lactic acid bacteria (LAB) have long been used in industrial applications mainly as starters for food fermentation or as biocontrol agents or as probiotics. However, LAB possess several characteristics that render them among the most promising candidates for use in future biorefineries in converting plant-derived biomass-either from dedicated crops or from municipal/industrial solid wastes-into biofuels and high value-added products. Lactic acid, their main fermentation product, is an attractive building block extensively used by the chemical industry, owing to the potential for production of polylactides as biodegradable and biocompatible plastic alternative to polymers derived from petrochemicals. LA is but one of many high-value compounds which can be produced by LAB fermentation, which also include biofuels such as ethanol and butanol, biodegradable plastic polymers, exopolysaccharides, antimicrobial agents, health-promoting substances and nutraceuticals. Furthermore, several LAB strains have ascertained probiotic properties, and their biomass can be considered a high-value product. The present contribution aims to provide an extensive overview of the main industrial applications of LAB and future perspectives concerning their utilization in biorefineries. Strategies will be described in detail for developing LAB strains with broader substrate metabolic capacity for fermentation of cheaper biomass. Copyright © 2014 Elsevier Inc. All rights reserved.
Rasapoor, Mazdak; Adl, Mehrdad; Baroutian, Saeid; Iranshahi, Zeynab; Pazouki, Mohammad
2018-04-30
It has been proven that ultrasonic pretreatment (UP) has positive effect on biogas generation from previous lab-scale studies. However, that is not always the case in larger scale processes. The purpose of this study was to evaluate the effectiveness of UP to biogas generation in terms of anaerobic digestion process and energy efficiency. Parameters including total solids (TS) and ultrasonic treatment operational parameters of organic solid waste (OSW) resulted from our past lab scale UP studies were applied in this study. OSW with 6-10% TS was treated using a lab-scale ultrasonic processor using various power densities (0.2-0.6 W/mL) at different time periods up to 30 min. Results of lab scale confirmed that OSW with 6% TS sonicated with 0.2 W/mL power density in 30 min gave the best outcome for the pilot scale experiment. To simulate the condition of an actual scale, in addition to energy analysis, two different organic loading rates (OLR), namely 500 and 1500 gVS/m 3 day were examined. The pilot digester was fed with OSW with or without the pretreatment based on the aforementioned specifications. The results showed that UP effectively improves biogas generation in terms of quantity and quality (CH 4 /CO 2 ). Furthermore, it decreases the time to reach the maximum cumulative biogas volume comparing to the untreated feed. The key achievement of this research has confirmed that although the relative increase in the energy gain by the influence of UP was more remarkable under the 500 gVS/m 3 day OLR, energy analysis showed a better energy gain and energy benefit as well as jumping in biogas yield up to 80% for UP treated OSW under 1500 gVS/m 3 day OLR. Copyright © 2018 Elsevier B.V. All rights reserved.
Quality of ground water in Harrison County, Mississippi, June - July 1993
Slack, L.J.; Oakley, W.T.; O'Hara, C. G.; Cooper, L.M.
1994-01-01
During June and July 1993, the U.S. Geological Survey analyzed water from 145 wells in Harrison County, southeastern Mississippi. The wells are completed in five major geologic units: the Citronelle, Graham Ferry, Pascagoula, and Hattiesburg Formations and the Catahoula Sandstone. The wells ranged from 74 to 2,410 feet in depth. Specific conductance (lab) ranged from 15 to 2,020 microsiemens per centimeter; pH (lab), from 5.9 to 9.0; color, from less than 5 to 120 platinum-cobalt units; dissolved-solids concentrations (residue on evaporation), from 20 to 1,120 milligrams per liter; chloride concentrations, from 1.9 to 470 milligrams per liter; and nitrite plus nitrate as nitrogen concentrations, from less than 0.02 to 0.85 milligram per liter. Most of the larger values of specific conductance, pH, dissolved-solids concen- trations, and chloride concentrations were from wells in the southern one-half of the county.
Lif and Raman Spectroscopy in Undergraduate Labs Using Green Diode-Pumped Solid-State Lasers
NASA Astrophysics Data System (ADS)
Gray, Jeffrey A.
2015-06-01
Electronic spectroscopy of molecular iodine vapor has long been studied in undergraduate physical chemistry teaching laboratories, but the effectiveness of emission work has typically been limited by availability of instrumentation. This talk shows how to make inexpensive green diode-pumped solid-state (DPSS) lasers easily tunable for efficient, selective excitation of I2. Miniature fiber-optic spectrometers then enable rotationally resolved fluorescence spectroscopy up to v" = 42 near 900 nm with acquisition times of less than one minute. DPSS lasers are also versatile excitation sources for vibrational Raman spectroscopy, which is another common exercise that has been limited by lack of proper instrumentation in the teaching laboratory. This talk shows how to construct a simple accessory for commercial fluorimeters to record vibrational Raman spectra and depolarization ratios for CCl4 and C2Cl4 as part of a lab exercise featuring molecular symmetry.
Bertuna, Angela; Faglia, Guido; Ferroni, Matteo; Kaur, Navpreet; Munasinghe Arachchige, Hashitha M. M.; Sberveglieri, Giorgio; Comini, Elisabetta
2017-01-01
Metal oxide 1D nanowires are probably the most promising structures to develop cheap stable and selective chemical sensors. The purpose of this contribution is to review almost two-decades of research activity at the Sensor Lab Brescia on their preparation during by vapor solid (n-type In2O3, ZnO), vapor liquid solid (n-type SnO2 and p-type NiO) and thermal evaporation and oxidation (n-type ZnO, WO3 and p-type CuO) methods. For each material we’ve assessed the chemical sensing performance in relation to the preparation conditions and established a rank in the detection of environmental and industrial pollutants: SnO2 nanowires were effective in DMMP detection, ZnO nanowires in NO2, acetone and ethanol detection, WO3 for ammonia and CuO for ozone. PMID:28468310
Observations in the 1.3 and 1.5 THz atmospheric windows with the Receiver Lab Telescope
NASA Technical Reports Server (NTRS)
Marrone, Daniel P.; Blundell, Raymond; Tong, Edward; Paine, Scott N.; Loudkov, Denis; Kawamura, Jonathan H.; Luhr, Daniel; Barrientos, Claudio
2005-01-01
The Receiver Lab Telescope (RLT) is a groundbased terahertz telescope; it is currently the only instrument producing astronomical data between 1 and 2 THz. The capabilities of the RLT have been expanding since observations began in late 2002. Initial observations were limited to the 850 GHz and 1.03 THz windows due to the availability of solid state local oscillators. In the last year we have begun observations with new local oscillators for the 1.3 and 1.5 THz atmospheric windows.
2013-12-01
Implementation of current NPS TPL design procedure that uses COTS software (MATLAB, SolidWorks, and ANSYS - CFX ) for the geometric rendering and...procedure that uses commercial-off-the-shelf software (MATLAB, SolidWorks, and ANSYS - CFX ) for the geometric rendering and analysis was modified and... CFX The CFD simulation program in ANSYS Workbench. CFX -Pre CFX boundary conditions and solver settings module. CFX -Solver CFX solver program. CFX
The Barium Hydroxide-Ammonium Thiocyanate Reaction: A Titrimetric Continuous Variations Experiment.
ERIC Educational Resources Information Center
Harris, Arlo D.
1979-01-01
Presents an experiment for inorganic, organic, or physical chemistry students utilizing acid-base titrimetry to study the stoichiometric of a solid state reaction. Time involved ranges from one to three, three-hour lab periods. (Author/SA)
Lanthanum hexaboride for solar energy applications.
Sani, Elisa; Mercatelli, Luca; Meucci, Marco; Zoli, Luca; Sciti, Diletta
2017-04-06
We investigate the optical properties of LaB 6 - based materials, as possible candidates for solid absorbers in Concentrating Solar Power (CSP) systems. Bulk LaB 6 materials were thermally consolidated by hot pressing starting from commercial powders. To assess the solar absorbance and spectral selectivity properties, room-temperature hemispherical reflectance spectra were measured from the ultraviolet to the mid-infrared, considering different compositions, porosities and surface roughnesses. Thermal emittance at around 1100 K has been measured. Experimental results showed that LaB 6 can have a solar absorbance comparable to that of the most advanced solar absorber material in actual plants such as Silicon Carbide, with a higher spectral selectivity. Moreover, LaB 6 has also the appealing characteristics to be a thermionic material, so that it could act at the same time both as direct high-temperature solar absorber and as electron source, significantly reducing system complexity in future concentrating solar thermionic systems and bringing a real innovation in this field.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sitler, Steven J.; Raja, Krishnan S.; Charit, Indrajit
Solid solutions of HfB 2-ZrB 2 mixtures were prepared by high-energy ball milling of diboride and additive powders followed by spark plasma sintering (SPS). A mixture of stoichiometric 1:1 HfB 2-ZrB 2 borides was the base composition to which Hf, Zr, Ta, LaB 6 or Gd 2O 3 was added. Hf, Zr and Ta were added in order to bring the boron-to-metal ratio down to 1.86, rendering the boride as MeB 1.86. In the case of LaB 6 and Gd 2O 3, 1.8 mol% was added. Electroanalytical behavior of hydrogen evolution reactions was evaluated in 1 M H 2SO 4more » and 1 M NaOH solutions. The LaB 6 additive material showed Tafel slopes of 125 and 90 mV/decade in acidic and alkaline solutions respectively. The Hf and Zr rich samples showed Tafel slopes of about 120 mV/decade in both electrolytes. The over potentials of hydrogen evolution reactions (at 10 mA/cm 2) in the alkaline solution were about 100 mV lower than those in acidic solution. The metal-rich diborides and addition of LaB 6 showed better hydrogen evolution reaction (HER) activities than the base 1:1 HfB 2-ZrB 2 stoichiometric diboride solid solution. Furthermore, the higher activity of metal-rich borides could be attributed to the increased electron population at the d-orbitals of the metal shown by band structure modeling calculations using the Density Functional Theory approach.« less
Saro, Cristina; Molina-Alcaide, Eduarda; Abecia, Leticia; Ranilla, María José; Carro, María Dolores
2018-04-01
The objective of this study was to compare the automated ribosomal intergenic spacer analysis (ARISA) and the denaturing gradient gel electrophoresis (DGGE) techniques for analysing the effects of diet on diversity in bacterial pellets isolated from the liquid (liquid-associated bacteria (LAB)) and solid (solid-associated bacteria (SAB)) phase of the rumen. The four experimental diets contained forage to concentrate ratios of 70:30 or 30:70 and had either alfalfa hay or grass hay as forage. Four rumen-fistulated animals (two sheep and two goats) received the diets in a Latin square design. Bacterial pellets (LAB and SAB) were isolated at 2 h post-feeding for DNA extraction and analysed by ARISA and DGGE. The number of peaks in individual samples ranged from 48 to 99 for LAB and from 41 to 95 for SAB with ARISA, and values of DGGE-bands ranged from 27 to 50 for LAB and from 18 to 45 for SAB. The LAB samples from high concentrate-fed animals tended (p < 0.10) to show greater peak numbers and Shannon index values than those isolated from high forage-fed animals with ARISA, but no differences were identified with DGGE. The SAB samples from high concentrate-fed animals had lower (p < 0.05) peak numbers and Shannon index values than those from animals fed high-forage diets with ARISA, but only a trend was noticed for these parameters with DGGE (p < 0.10). The ARISA detected that animals fed alfalfa hay diets showed lower (p < 0.05) SAB diversity than those fed grass hay diets, but no differences were observed with DGGE. No effect of forage type on LAB diversity was detected by any technique. In this study, ARISA detected some changes in ruminal bacterial communities that were not detected by DGGE, and therefore ARISA was considered more appropriate for assessing bacterial diversity of ruminal bacterial pellets. The results highlight the impact of the fingerprinting technique used to draw conclusions on dietary factors affecting bacterial diversity in ruminal bacterial pellets.
KSC Electrostatic Discharge (ESD) Issues
NASA Technical Reports Server (NTRS)
Buhler, Charles
2008-01-01
Discussion of key electrostatic issues that have arisen during the past few years at KSC that the Electrostatics Laboratory has studied. The lab has studied in depth the Space Shuttle's Thermal Control System Blankets, the International Space Station Thermal Blanket, the Pan/Tilt Camera Blankets, the Kapton Purge Barrier Curtain, the Aclar Purge Barrier Curtain, the Thrust Vector Controller Blankets, the Tyvek Reaction Control System covers, the AID-PAK and FLU-9 pyro inflatable devices, the Velostat Solid Rocket Booster mats, and the SCAPE suits. In many cases these materials are insulating meaning that they might be a source of unsafe levels of electrostatic discharge (ESD). For each, the lab provided in-depth testing of each material within its current configuration to ensure that it does not cause an ESD concern that may violate the safety of the astronauts, the workers and equipment for NASA. For example the lab provides unique solutions and testing such as Spark Incendivity Testing that checks whether a material is capable of generating a spark strong enough to ignite a flammable gas. The lab makes recommendations to changes in specifications, procedures, and material if necessary. The lab also consults with a variety of non-safety related ESD issues for the agency.
Zheng, Yu; Mou, Jun; Niu, Jiwei; Yang, Shuai; Chen, Lin; Xia, Menglei; Wang, Min
2018-03-01
Lactic acid bacteria (LAB) are essential microbiota for the fermentation and flavor formation of Shanxi aged vinegar, a famous Chinese traditional cereal vinegar that is manufactured using open solid-state fermentation (SSF) technology. However, the dynamics of LAB in this SSF process and the underlying mechanism remain poorly understood. Here, the diversity of LAB and the potential driving factors of the entire process were analyzed by combining culture-independent and culture-dependent methods. Canonical correlation analysis indicated that ethanol, acetic acid, and temperature that result from the metabolism of microorganisms serve as potential driving factors for LAB succession. LAB strains were periodically isolated, and the characteristics of 57 isolates on environmental factor tolerance and substrate utilization were analyzed to understand the succession sequence. The environmental tolerance of LAB from different stages was in accordance with their fermentation conditions. Remarkable correlations were identified between LAB growth and environmental factors with 0.866 of ethanol (70 g/L), 0.756 of acetic acid (10 g/L), and 0.803 of temperature (47 °C). More gentle or harsh environments (less or more than 60 or 80 g/L of ethanol, 5 or 20 g/L of acetic acid, and 30 or 55 °C temperature) did not affect the LAB succession. The utilization capability evaluation of the 57 isolates for 95 compounds proved that strains from different fermentation stages exhibited different predilections on substrates to contribute to the fermentation at different stages. Results demonstrated that LAB succession in the SSF process was driven by the capabilities of environmental tolerance and substrate utilization.
STS-98 U.S. Lab Destiny is moved out of Atlantis' payload bay
NASA Technical Reports Server (NTRS)
2001-01-01
KENNEDY SPACE CENTER, Fla. -- The U.S. Lab Destiny is ready to be moved from Atlantis''' payload bay into the Payload Changeout Room. After the move, Atlantis will roll back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster'''s system tunnel. An extensive evaluation of NASA'''s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis.
Nanoelectric Materials Laboratory Development
NASA Technical Reports Server (NTRS)
Allen, Lee; Hill, Curtis
2015-01-01
The Ultracapacitor Research and Development project is a collaborative effort between the NASA Marshall Space Flight Center's (MSFC's) ES43 Parts, Packaging, and Fabrication Branch and the EM41 Nonmetallic Materials Branch. NASA's Ultracapacitor Research is an effort to develop solid-state energy storage devices through processing of ceramic materials into printable dielectric inks, which can be formed and treated to produce solid state ultracapacitor cells capable of exceeding lithium-ion battery energy density at a fraction of the weight. Research and development efforts into solid state ultracapacitors have highlighted a series of technical challenges such as understanding as-received nature of ceramic powders, treatment and optimization of ceramic powders, dielectric and conductor ink formulation, and firing of printed (green) ultracapacitor cells. Two facilities have been continually developed since project inception: the Additive Electronics Lab in Bldg. 4487 and the Nanoelectric Materials Lab in Bldg. 4602. The Nanoelectric Materials Lab has become a unique facility at MSFC, capable of custom processing a wide range of media for additive electronics. As research has progressed, it was discovered that additional in-house processing was necessary to achieve smaller, more uniform particle diameters. A vibratory mill was obtained that can agitate powder and media in three directions, which has shown to be much more effective than ball milling. However, in order to understand the effects of milling, a particle size analysis system has been installed to characterize as-received and milled materials Continued research into the ultracapacitor technology included advanced milling and optimization of ceramic nanoparticles, fluidized bed treatment of atomic-layer deposition- (ALD-) coated ceramic particles, custom development of dielectric and conductor inks, as well as custom ink precursors such as polyvinylidene diflouride- (PVDF-) loaded vehicles. Experiments with graphene-based inks were also conducted.
Peoria Disposal Co.`s PDC Laboratories: Analyzing and cleaning up -- Literally
DOE Office of Scientific and Technical Information (OSTI.GOV)
McAdams, C.L.
1995-10-01
In the early 1980s, says Royal Coulter, president and CEO of Peoria Disposal Co. (PDC, Peoria, IL), many PDC customers were unfamiliar with the methods required for the proper characterization of then newly regulated hazardous wastes. So in early 1981, to expedite permitting and, ultimately, acceptance of waste by PDC, a lab was set up so the company could step in and provide the needed services. By focusing on the delivery of quality services in the analysis of groundwater, wastewater, and solid waste for PDC, Coulter says, the laboratory soon developed into a successful and independent commercial operation. In Julymore » of 1981, PDC Laboratories was incorporated as an independent environmental analytical laboratory. PDC Labs is a subsidiary of PDC Technical Services, Inc., which provides environmental consulting and site remediation services, and is itself a wholly-owned subsidiary of Coulter Companies, Inc. Peoria Disposal offers solid waste disposal, industrial waste water treatment, waste stabilization, transportation services, and brokerage services.« less
NASA Astrophysics Data System (ADS)
Xu, Yuanhong; Liu, Jingquan; Zhang, Jizhen; Zong, Xidan; Jia, Xiaofang; Li, Dan; Wang, Erkang
2015-05-01
A portable lab-on-a-chip methodology to generate ionic liquid-functionalized carbon nanodots (CNDs) was developed via electrochemical oxidation of screen printed carbon electrodes. The CNDs can be successfully applied for efficient cell imaging and solid-state electrochemiluminescence sensor fabrication on the paper-based chips.A portable lab-on-a-chip methodology to generate ionic liquid-functionalized carbon nanodots (CNDs) was developed via electrochemical oxidation of screen printed carbon electrodes. The CNDs can be successfully applied for efficient cell imaging and solid-state electrochemiluminescence sensor fabrication on the paper-based chips. Electronic supplementary information (ESI) available: Experimental section; Fig. S1. XPS spectra of the as-prepared CNDs after being dialyzed for 72 hours; Fig. S2. LSCM images showing time-dependent fluorescence signals of HeLa cells treated by the as-prepared CNDs; Tripropylamine analysis using the Nafion/CNDs modified ECL sensor. See DOI: 10.1039/c5nr01765c
NASA Astrophysics Data System (ADS)
Pardoen, Thomas; Colla, Marie-Sthéphane; Idrissi, Hosni; Amin-Ahmadi, Behnam; Wang, Binjie; Schryvers, Dominique; Bhaskar, Umesh K.; Raskin, Jean-Pierre
2016-03-01
A nanomechanical on-chip test platform has recently been developed to deform under a variety of loading conditions freestanding thin films, ribbons and nanowires involving submicron dimensions. The lab-on-chip involves thousands of elementary test structures from which the elastic modulus, strength, strain hardening, fracture, creep properties can be extracted. The technique is amenable to in situ transmission electron microscopy (TEM) investigations to unravel the fundamental underlying deformation and fracture mechanisms that often lead to size-dependent effects in small-scale samples. The method allows addressing electrical and magnetic couplings as well in order to evaluate the impact of large mechanical stress levels on different solid-state physics phenomena. We had the chance to present this technique in details to Jacques Friedel in 2012 who, unsurprisingly, made a series of critical and very relevant suggestions. In the spirit of his legacy, the paper will address both mechanics of materials related phenomena and couplings with solids state physics issues.
NASA Astrophysics Data System (ADS)
Susilowati, Agustine; Aspiyanto, Maryati, Yati; Melanie, Hakiki; Lotulung, Puspa D.
2017-01-01
Purifying broccoli (Brassica oleracea L.) fermented by Lactic Acid Bacteria (LAB) using mixture of L. bulgaricus, S. thermopillus, L. acidophillusand Bifidobacteriumbifidum and fructooligosaccharides (FOS) as carbon source have been performed to recover biomass concentrate for probiotic and antioxidant. Purification of fermented broccoli was conducted through microfiltration (MF) membrane of 0.15 µm at stirrer rotation speed 400 rpm, room temperature and pressure 40 psia for 30 minutes. Fermented broccoli produced via fermentation process with fermentation time 0 (initial) and 48 hours, and LAB concentration 10% and 20% (v/v) represented as biomass of A, B, C and D. The experimental result showed that based on selectivity of total organic acids, separating optimization was achieved at biomass D (fermentation time 48 hours and mixed LAB culture concentration 20%). Concentrate composition produced in this condition were total acids 6.04%, total solids 24.31%, total polyphenol 0.0252%, reducing sugar 68.25 mg/mL, total sugars 30.89 mg/mL, and dissolved protein 28.54 mg/mL with pH 3.94. In this condition, recovery of biomass concentrate of D for total acids 5.64 folds, total solids 1.82 folds, total polyphenol 3.03 folds, reducing sugar 1.16 folds, total sugars 1.19 folds, and dissolved protein 0.67 folds compared with feed (initial process). Identification of monomer of biomass concentrate D as polyphenol derivatives at T2,01 and T3.01 gave monomer with molecular weight (MW) 192.78 Dalton (Da.), and monomer with MW 191.08, 191.49 and 192.07 Da., while lactic acid derivatives showed MW 251.13, 251.6 and 252.14, and monomer with MW 250.63, 252.14 and 254.22 Da.
Sitler, Steven J.; Raja, Krishnan S.; Charit, Indrajit
2016-09-23
Solid solutions of HfB 2-ZrB 2 mixtures were prepared by high-energy ball milling of diboride and additive powders followed by spark plasma sintering (SPS). A mixture of stoichiometric 1:1 HfB 2-ZrB 2 borides was the base composition to which Hf, Zr, Ta, LaB 6 or Gd 2O 3 was added. Hf, Zr and Ta were added in order to bring the boron-to-metal ratio down to 1.86, rendering the boride as MeB 1.86. In the case of LaB 6 and Gd 2O 3, 1.8 mol% was added. Electroanalytical behavior of hydrogen evolution reactions was evaluated in 1 M H 2SO 4more » and 1 M NaOH solutions. The LaB 6 additive material showed Tafel slopes of 125 and 90 mV/decade in acidic and alkaline solutions respectively. The Hf and Zr rich samples showed Tafel slopes of about 120 mV/decade in both electrolytes. The over potentials of hydrogen evolution reactions (at 10 mA/cm 2) in the alkaline solution were about 100 mV lower than those in acidic solution. The metal-rich diborides and addition of LaB 6 showed better hydrogen evolution reaction (HER) activities than the base 1:1 HfB 2-ZrB 2 stoichiometric diboride solid solution. Furthermore, the higher activity of metal-rich borides could be attributed to the increased electron population at the d-orbitals of the metal shown by band structure modeling calculations using the Density Functional Theory approach.« less
NOVEL OXIDANT FOR ELEMENTAL MERCURY CONTROL FROM FLUE GAS
The primary objective of this study is to develop and test advanced noncarbonaceous solid sorbent materials suitable for removing the elemental form of mercury from power plant emissions. An efficient and cost-effective novel Hg(0) oxidant was evaluated in a lab-scale fixed-bed ...
Revealing facts behind spray dried solid dispersion technology used for solubility enhancement
Patel, Bhavesh B.; Patel, Jayvadan K.; Chakraborty, Subhashis; Shukla, Dali
2013-01-01
Poor solubility and bioavailability of an existing or newly synthesized drug always pose challenge in the development of efficient pharmaceutical formulation. Numerous technologies can be used to improve the solubility and among them amorphous solid dispersion based spray drying technology can be successfully useful for development of product from lab scale to commercial scale with a wide range of powder characteristics. Current review deals with the importance of spray drying technology in drug delivery, basically for solubility and bioavailability enhancement. Role of additives, selection of polymer, effect of process and formulation parameters, scale up optimization, and IVIVC have been covered to gain the interest of readers about the technology. Design of experiment (DoE) to optimize the spray drying process has been covered in the review. A lot more research work is required to evaluate spray drying as a technology for screening the right polymer for solid dispersion, especially to overcome the issue related to drug re-crystallization and to achieve a stable product both in vitro and in vivo. Based on the recent FDA recommendation, the need of the hour is also to adopt Quality by Design approach in the manufacturing process to carefully optimize the spray drying technology for its smooth transfer from lab scale to commercial scale. PMID:27134535
Revealing facts behind spray dried solid dispersion technology used for solubility enhancement.
Patel, Bhavesh B; Patel, Jayvadan K; Chakraborty, Subhashis; Shukla, Dali
2015-09-01
Poor solubility and bioavailability of an existing or newly synthesized drug always pose challenge in the development of efficient pharmaceutical formulation. Numerous technologies can be used to improve the solubility and among them amorphous solid dispersion based spray drying technology can be successfully useful for development of product from lab scale to commercial scale with a wide range of powder characteristics. Current review deals with the importance of spray drying technology in drug delivery, basically for solubility and bioavailability enhancement. Role of additives, selection of polymer, effect of process and formulation parameters, scale up optimization, and IVIVC have been covered to gain the interest of readers about the technology. Design of experiment (DoE) to optimize the spray drying process has been covered in the review. A lot more research work is required to evaluate spray drying as a technology for screening the right polymer for solid dispersion, especially to overcome the issue related to drug re-crystallization and to achieve a stable product both in vitro and in vivo. Based on the recent FDA recommendation, the need of the hour is also to adopt Quality by Design approach in the manufacturing process to carefully optimize the spray drying technology for its smooth transfer from lab scale to commercial scale.
Impact of solid state fermentation on nutritional, physical and flavor properties of wheat bran.
Zhao, Hui-Min; Guo, Xiao-Na; Zhu, Ke-Xue
2017-02-15
To improve the nutritional, physical and flavor properties of wheat bran, yeast and lactic acid bacteria (LAB) were used for fermenting wheat bran in solid state. Appearance properties, nutritional properties, microstructure, hydration properties and flavor of raw bran and fermented bran were evaluated. After treatments, water extractable arabinoxylans were 3-4 times higher than in raw bran. Total dietary fiber and soluble dietary fiber increased after solid state fermentation. Over 20% of phytic acid was degraded. Microstructure changes and protein degradation were observed in fermented brans. Water holding capacity and water retention capacity of fermented brans were improved. Results suggest that solid state fermentation is an effective way to improve the properties of wheat brans. Copyright © 2016 Elsevier Ltd. All rights reserved.
Space lab system analysis: Advanced Solid Rocket Motor (ASRM) communications networks analysis
NASA Technical Reports Server (NTRS)
Ingels, Frank M.; Moorhead, Robert J., II; Moorhead, Jane N.; Shearin, C. Mark; Thompson, Dale R.
1990-01-01
A synopsis of research on computer viruses and computer security is presented. A review of seven technical meetings attended is compiled. A technical discussion on the communication plans for the ASRM facility is presented, with a brief tutorial on the potential local area network media and protocols.
STS-98 U.S. Lab Destiny is moved out of Atlantis' payload bay
NASA Technical Reports Server (NTRS)
2001-01-01
KENNEDY SPACE CENTER, Fla. -- The U.S. Lab Destiny begins moving out of Atlantis''' payload bay and into the Payload Changeout Room via the Payload Ground Handling Mechanism. Destiny will remain in the PCR while Atlantis rolls back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster'''s system tunnel. An extensive evaluation of NASA'''s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis.
STS-98 U.S. Lab Destiny is moved out of Atlantis' payload bay
NASA Technical Reports Server (NTRS)
2001-01-01
KENNEDY SPACE CENTER, Fla. -- The U.S. Lab Destiny (left) moves away from Atlantis''' payload bay doors (right) into the Payload Changeout Room. Destiny will remain in the PCR while Atlantis rolls back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster'''s system tunnel. An extensive evaluation of NASA'''s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis.
STS-98 U.S. Lab Destiny is moved out of Atlantis' payload bay
NASA Technical Reports Server (NTRS)
2001-01-01
KENNEDY SPACE CENTER, Fla. -- Workers in the Payload Changeout Room check the U.S. Lab Destiny as its moves from Atlantis''' payload bay into the PCR. Destiny will remain in the PCR while Atlantis rolls back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster'''s system tunnel. An extensive evaluation of NASA'''s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis.
STS-98 U.S. Lab Destiny is moved out of Atlantis' payload bay
NASA Technical Reports Server (NTRS)
2001-01-01
KENNEDY SPACE CENTER, Fla. -- The U.S. Lab Destiny moves out of Atlantis''' payload bay and into the Payload Changeout Room via the Payload Ground Handling Mechanism. Destiny will remain in the PCR while Atlantis rolls back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster'''s system tunnel. An extensive evaluation of NASA'''s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis.
NASA Astrophysics Data System (ADS)
Maloney, A.; Walsh, E.
2012-12-01
A solid understanding of timescales is crucial for any climate change discussion. This hands-on lab was designed as part of a dual-credit climate change course in which high school students can receive college credit. Using homemade ice cores, students have the opportunity to participate in scientific practices associated with collecting, processing, and interpreting temperature and CO2 data. Exploring millennial-scale cycles in ice core data and extending the CO2 record to the present allows students to discover timescales from an investigators perspective. The Ice Core Lab has been piloted in two high school classrooms and student engagement, and epistemological and conceptual understanding was evaluated using quantitative pre and post assessment surveys. The process of creating this lab involved a partnership between an education assessment professional, high school teachers, and University of Washington professors and graduate students in Oceanography, Earth and Space Sciences, Atmospheric Sciences and the Learning Sciences as part of the NASA Global Climate Change University of Washington in the High School program. This interdisciplinary collaboration led to the inception of the lab and was necessary to ensure that the lesson plan was pedagogically appropriate and scientifically accurate. The lab fits into a unit about natural variability and is paired with additional hands-on activities created by other graduate students that explore short-timescale temperature variations, Milankovitch cycles, isotopes, and other proxies. While the Ice Core Lab is intended to follow units that review the scientific process, global energy budget, and transport, it can be modified to fit any teaching platform.
Ultrasonic Processing of Materials
NASA Astrophysics Data System (ADS)
Han, Qingyou
2015-08-01
Irradiation of high-energy ultrasonic vibration in metals and alloys generates oscillating strain and stress fields in solids, and introduces nonlinear effects such as cavitation, acoustic streaming, and radiation pressure in molten materials. These nonlinear effects can be utilized to assist conventional material processing processes. This article describes recent research at Oak Ridge National Labs and Purdue University on using high-intensity ultrasonic vibrations for degassing molten aluminum, processing particulate-reinforced metal matrix composites, refining metals and alloys during solidification process and welding, and producing bulk nanostructures in solid metals and alloys. Research results suggest that high-intensity ultrasonic vibration is capable of degassing and dispersing small particles in molten alloys, reducing grain size during alloy solidification, and inducing nanostructures in solid metals.
NASA Astrophysics Data System (ADS)
Steyn, Gideon; Vermeulen, Christiaan; Isaacs, Eugene
2018-05-01
The techniques employed at iThemba LABS for the encapsulation of solid radionuclide production targets, based on cold indentation welding, electron beam welding and laser welding, are described. Some aspects of the target holders and cooling requirements to bombard targets in a tandem configuration with a 66 MeV proton beam, with intensities up to nominally 250 A, are also briefly discussed. These techniques are inter alia suitable for a production regimen compatible with the new generation of commercial, high-intensity 70 MeV cyclotrons.
Lab-scale investigation on remediation of diesel-contaminated aquifer using microwave energy.
Falciglia, Pietro P; Maddalena, Riccardo; Mancuso, Giuseppe; Messina, Valeria; Vagliasindi, Federico G A
2016-02-01
Aquifer contamination with diesel fuel is a worldwide environmental problem, and related available remediation technologies may not be adequately efficient, especially for the simultaneous treatment of both solid and water phases. In this paper, a lab-scale 2.45 GHz microwave (MW) treatment of an artificially diesel-contaminated aquifer was applied to investigate the effects of operating power (160, 350 and 500 W) and time on temperature profiles and contaminant removal from both solid and water phases. Results suggest that in diesel-contaminated aquifer MW remediation, power significantly influences the final reachable temperature and, consequently, contaminant removal kinetics. A maximum temperature of about 120 °C was reached at 500 W. Observed temperature values depended on the simultaneous irradiation of both aquifer grains and groundwater. In this case, solid phase heating is limited by the maximum temperature that interstitial water can reach before evaporation. A minimal residual diesel concentration of about 100 mg kg(-1) or 100 mg L(-1) was achieved by applying a power of 500 W for a time of 60 min for the solid or water phase, respectively. Measured residual TPH fractions showed that MW heating resulted in preferential effects of the removal of different TPH molecular weight fractions and that the evaporation-stripping phenomena plays a major role in final contaminant removal processes. The power low kinetic equation shows an excellent fit (r(2) > 0.993) with the solid phase residual concentration observed for all the powers investigated. A maximum diesel removal of 88 or 80% was observed for the MW treatment of the solid or water phase, respectively, highlighting the possibility to successfully and simultaneously remediate both the aquifer phases. Consequently, MW, compared to other biological or chemical-physical treatments, appears to be a better choice for the fast remediation of diesel-contaminated aquifers. Copyright © 2015 Elsevier Ltd. All rights reserved.
2017-01-01
The hydrodynamics and heat transfer of cylindrical gas–solid fluidized beds for polyolefin production was investigated with the two-fluid model (TFM) based on the kinetic theory of granular flow (KTGF). It was found that the fluidized bed becomes more isothermal with increasing superficial gas velocity. This is mainly due to the increase of solids circulation and improvement in gas solid contact. It was also found that the average Nusselt number weakly depends on the gas velocity. The TFM results were qualitatively compared with simulation results of computational fluid dynamics combined with the discrete element model (CFD-DEM). The TFM results were in very good agreement with the CFD-DEM outcomes, so the TFM can be a reliable source for further investigations of fluidized beds especially large lab-scale reactors PMID:29187774
The vacuum tribology model (VTM) of TriboLAB
NASA Astrophysics Data System (ADS)
Garmendia, I.; Landaberea, A.; Anglada, E.; Fernández-Sanz, R.; Santiago, R.; Herrada, F.; Encinas, J. M.
2003-09-01
TriboLAB is a tribology instrument that is planned for installation in the EuteF Flight Segment Platform, along with several other European scientific instruments. EuteF will be fixed onto an Express Pallet Adapter (ExPA), which provides standard structural, mechanical, electrical and communications interfaces to the Columbus External Payload Facility of the International Space Station (ISS). As a part of the model philosophy, a vacuum tribological model (VTM) has been developed to generate "on ground" tribological data of selected lubricants. The idea is to compare the results obtained "on ground" with those that will be produced in the space, in order to investigate the different behaviors of same tribological films and to be able to compare the performance of specific lubricants in Low Earth Orbit (LEO) conditions. The VTM is composed of six double experiment cells that perform respectively ball bearing (BB) experiments (with liquid and solid lubrication) and pin-on-disk (PoD) tests of solid lubricants. Thin films of alloyed MoS2 are being tested in the VTM under controlled vacuum conditions. In this work, the two sections of the VTM are described.
PREFACE: 1st Tensor Polarized Solid Target Workshop
NASA Astrophysics Data System (ADS)
2014-10-01
These are the proceedings of the first Tensor Spin Observables Workshop that was held in March 2014 at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia. The conference was convened to study the physics that can be done with the recently approved E12-13-011 polarized target. A tensor polarized target holds the potential of initiating a new generation of tensor spin physics at Jefferson Lab. Experiments which utilize tensor polarized targets can help clarify how nuclear properties arise from partonic degrees of freedom, provide unique insight into short-range correlations and quark angular momentum, and also help pin down the polarization of the quark sea with a future Electron Ion Collider. This three day workshop was focused on tensor spin observables and the associated tensor target development. The workshop goals were to stimulate progress in the theoretical treatment of polarized spin-1 systems, foster the development of new proposals, and to reach a consensus on the optimal polarized target configuration for the tensor spin program. The workshop was sponsored by the University of New Hampshire, the Jefferson Science Associates, Florida International University, and Jefferson Lab. It was organized by Karl Slifer (chair), Patricia Solvignon, and Elena Long of the University of New Hampshire, Douglas Higinbotham and Christopher Keith of Jefferson Lab, and Misak Sargsian of the Florida International University. These proceedings represent the effort put forth by the community to begin exploring the possibilities that a high-luminosity, high-tensor polarized solid target can offer.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Saar, Martin O.; Seyfried, Jr., William E.; Longmire, Ellen K.
2016-06-24
A total of 12 publications and 23 abstracts were produced as a result of this study. In particular, the compilation of a thermodynamic database utilizing consistent, current thermodynamic data is a major step toward accurately modeling multi-phase fluid interactions with solids. Existing databases designed for aqueous fluids did not mesh well with existing solid phase databases. Addition of a second liquid phase (CO2) magnifies the inconsistencies between aqueous and solid thermodynamic databases. Overall, the combination of high temperature and pressure lab studies (task 1), using a purpose built apparatus, and solid characterization (task 2), using XRCT and more developed technologies,more » allowed observation of dissolution and precipitation processes under CO2 reservoir conditions. These observations were combined with results from PIV experiments on multi-phase fluids (task 3) in typical flow path geometries. The results of the tasks 1, 2, and 3 were compiled and integrated into numerical models utilizing Lattice-Boltzmann simulations (task 4) to realistically model the physical processes and were ultimately folded into TOUGH2 code for reservoir scale modeling (task 5). Compilation of the thermodynamic database assisted comparisons to PIV experiments (Task 3) and greatly improved Lattice Boltzmann (Task 4) and TOUGH2 simulations (Task 5). PIV (Task 3) and experimental apparatus (Task 1) have identified problem areas in TOUGHREACT code. Additional lab experiments and coding work has been integrated into an improved numerical modeling code.« less
STS-98 U.S. Lab Destiny is moved out of Atlantis' payload bay
NASA Technical Reports Server (NTRS)
2001-01-01
KENNEDY SPACE CENTER, Fla. -- Workers in the Payload Changeout Room check the Payload Ground Handling Mechanism that will move the U.S. Lab Destiny out of Atlantis''' payload bay and into the PCR. After the move, Atlantis will roll back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster'''s system tunnel. An extensive evaluation of NASA'''s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis.
What are gas hydrates?: Chapter 1
Beaudoin, Y.C.; Waite, W.; Boswell, R.; Dallimore, Scott
2014-01-01
The English chemistry pioneer Sir Humphry Davy first combined gas and water to produce a solid substance in his lab in 1810. For more than a century after that landmark moment, a small number of scientists catalogued various solid “hydrates” formed by combining water with an assortment of gases and liquids. Sloan and Koh (2007) review this early research, which was aimed at discerning the chemical structures of gas hydrates (Fig. 1.1), as well as the pressures and temperatures at which they are stable. Because no practical applications were found for these synthetic gas hydrates, they remained an academic curiosity.
Volume reduction of hot cell plastic wastes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dykes, F W; Henscheid, J P; Lewis, L C
1989-09-19
The disposal of radioactively-contaminated solid wastes has become a national crisis. In such circumstances, it is imperative that this waste be reduced to minimum volume and be packaged to prevent pollution of the environment. The majority of the solid waste generated at the hot cell under consideration is plastic lab ware. Cutting this waste into small pieces with a hot wire technique reduced the volume 66%. Melting the waste, although more time consuming, reduced the volume 90%. The hot wire technique can also be used to cut up damaged master slave manipulator boots, greatly reducing their disposal volume.
Hadronization Studies via π 0 Electroproduction off D, C, Fe, and Pb
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mineeva, Taisiya
2013-12-01
Propagation of partons and formation of hadrons is a topic of interest to multiple communities. New data available from Drell-Yan measurements at FermiLab, heavy ion collisions in RHIC and LHC, SIDIS measurements from HERMES at DESY and Jefferson Lab, all bring different types of information on short distance processes. DIS data obtained in the well understood nuclear medium provide direct information on hadron formation, essential to lay the groundwork for testing theoretical tools. A series of semi-inclusive DIS measurements were performed on D, C, Fe, Pb nuclei. The data were collected during the EG2 run period using the CLAS at Jefferson Lab. A double-target system consisting of liquid deuterium and one of the solid targets was exposed to a 5.014 GeV electron beam. The goal of the experiment is to extract hadronic multiplicity ratios (Rmore » $$h\\atop{A}$$) off nuclei of varying size. These are believed to have sensitivity to the parton fragmentation as well as in-medium hadronization.« less
NASA Astrophysics Data System (ADS)
Marr, Michael; Waldbillig, David; Kesler, Olivera
2013-03-01
Suspension plasma-sprayed YSZ coatings were deposited at lab-scale and production-type facilities to investigate the effect of process equipment on coating properties. The target application for these coatings is solid oxide fuel cell (SOFC) electrolytes; hence, dense microstructures with low permeability values were preferred. Both facilities had the same torch but different suspension feeding systems, torch robots, and substrate holders. The lab-scale facility had higher torch-substrate relative speeds compared with the production-type facility. On porous stainless steel substrates, permeabilities and microstructures were comparable for coatings from both facilities, and no segmentation cracks were observed. Coating permeability was further reduced by increasing substrate temperatures during deposition or reducing suspension feed rates. On SOFC cathode substrates, coatings made in the production-type facility had higher permeabilities and more segmentation cracks compared with coatings made in the lab-scale facility. Increased cracking in coatings from the production-type facility was likely caused mainly by its lower torch-substrate relative speed.
Object Creation and Human Factors Evaluation for Virtual Environments
NASA Technical Reports Server (NTRS)
Lindsey, Patricia F.
1998-01-01
The main objective of this project is to provide test objects for simulated environments utilized by the recently established Army/NASA Virtual Innovations Lab (ANVIL) at Marshall Space Flight Center, Huntsville, Al. The objective of the ANVIL lab is to provide virtual reality (VR) models and environments and to provide visualization and manipulation methods for the purpose of training and testing. Visualization equipment used in the ANVIL lab includes head-mounted and boom-mounted immersive virtual reality display devices. Objects in the environment are manipulated using data glove, hand controller, or mouse. These simulated objects are solid or surfaced three dimensional models. They may be viewed or manipulated from any location within the environment and may be viewed on-screen or via immersive VR. The objects are created using various CAD modeling packages and are converted into the virtual environment using dVise. This enables the object or environment to be viewed from any angle or distance for training or testing purposes.
Characterizing Optical Loss in Orientation Patterned III-V Materials using Laser Calorimetry
2014-03-27
nm and solid state fiber lasers . A comparison of the important properties of commonly used frequency conversion materials are shown in Table 1 [9......templates at AFRL. 32 Laser Calorimetry Experiment A THOR Labs ITC 4001 Laser diode with a 1625 nm, 50 mW fiber pigtail was used as the source
Research Animal Holding Facility Prevents Space Lab Contamination
NASA Technical Reports Server (NTRS)
Savage, P. D., Jr.; Jahns, G. C.; Dalton, B. P.; Hogan, R. P.; Wray, A. E.
1991-01-01
Healthy environment for both rodents and human researchers maintained. Research animal holding facility (RAHF) and rodent cage prevent solid particles (feces, food bits, hair), micro-organisms, ammonia, and odors from escaping into outside environment during spaceflight. Rodent cage contains compartments for two animals. Provides each drinking-water dispenser, feeding alcove, and activity-monitoring port. Feeding and waste trays removable.
Test SCRs and Triacs with a Lab-Built Checker
ERIC Educational Resources Information Center
Harman, Charles
2010-01-01
Students enrolled in advanced electronics courses and/or industrial electronics classes at the high school level and at technical colleges ultimately learn about solid-state switches such as the SCR (silicon controlled rectifier) and the triac. Both the SCR and the triac are in a family of four-layer devices called thyristors. They are both…
Schievano, Andrea; D'Imporzano, Giuliana; Malagutti, Luca; Fragali, Emilio; Ruboni, Gabriella; Adani, Fabrizio
2010-07-01
High-solids anaerobic digestion (HSAD) processes, when applied to different types of organic fractions of municipal solid waste (OFMSW), may easily be subjected to inhibition due to organic overloading. In this study, a new approach for predicting these phenomena was proposed based on the estimation of the putrescibility (oxygen consumption in 20 h biodegradation, OD(20)) of the organic mixtures undergoing the HSAD process. Different wastes exhibiting different putrescibility were subjected to lab-scale batch-HSAD. Measuring the organic loading (OL) as volatile solids (VS) was found unsuitable for predicting overload inhibition, because similar VS contents corresponded to both inhibited and successful trials. Instead, the OL calculated as OD(20) was a very good indicator of the inhibiting conditions (inhibition started for OD(20)>17-18 g O(2)kg(-1)). This new method of predicting inhibition in the HSAD process of diverse OFMSW may be useful for developing a correct approach to the technology in very different contexts. Copyright (c) 2010 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hrad, Marlies; Gamperling, Oliver; Huber-Humer, Marion, E-mail: marion.huber-humer@boku.ac.at
Highlights: ► Current data on in situ aeration effects from the first Austrian full-scale case study. ► Data on lasting waste stabilisation after aeration completion. ► Information on the transferability of results from lab- to full-scale aeration. - Abstract: Sustainable landfilling has become a fundamental objective in many modern waste management concepts. In this context, the in situ aeration of landfills has been recognised for its potential to convert conventional anaerobic landfills into biological stabilised state, whereby both current and potential (long-term) emissions of the landfilled waste are mitigated. In recent years, different in situ aeration concepts have been successfullymore » applied in Europe, North America and Asia, all pursuing different objectives and strategies. In Austria, the first full-scale application of in situ landfill aeration by means of low pressure air injection and simultaneous off-gas collection and treatment was implemented on an old, small municipal solid waste (MSW) landfill (2.6 ha) in autumn 2007. Complementary laboratory investigations were conducted with waste samples taken from the landfill site in order to provide more information on the transferability of the results from lab- to full-scale aeration measures. In addition, long-term emission development of the stabilised waste after aeration completion was assessed in an ongoing laboratory experiment. Although the initial waste material was described as mostly stable in terms of the biological parameters gas generation potential over 21 days (GP{sub 21}) and respiration activity over 4 days (RA{sub 4}), the lab-scale experiments indicated that aeration, which led to a significant improvement of leachate quality, was accompanied by further measurable changes in the solid waste material under optimised conditions. Even 75 weeks after aeration completion the leachate, as well as gaseous emissions from the stabilised waste material, remained low and stayed below the authorised Austrian discharge limits. However, the application of in situ aeration at the investigated landfill is a factor 10 behind the lab-based predictions after 3 years of operation, mainly due to technical limitations in the full-scale operation (e.g. high air flow resistivity due to high water content of waste and temporarily high water levels within the landfill; limited efficiency of the aeration wells). In addition, material preparation (e.g. sieving, sorting and homogenisation) prior to the emplacement in Landfill Simulation Reactors (LSRs) must be considered when transferring results from lab- to full-scale application.« less
Potential Re-utilization of Composted Mangrove Litters for Pond Environment Quality Improvement
NASA Astrophysics Data System (ADS)
Dwi Hastuti, Endah; Budi Hastuti, Rini; Hariyati, Riche
2018-05-01
Production of mangrove litter from pruning and thinning activities is potential source of organic materials which could be re-utilized to improve pond environment quality and fertility. This research aimed to analyze the nutrient composition compost produced from mangrove litter and to describe the effect of compost application on pond quality. This research was conducted through two phases, including composting trial and application of compost on pond trial. Composting process was conducted for 45-60 days on mangrove litter achieved from pruning activities in the silvofishery pond using composting container, while application of compost in pond was conducted by pouring 2 kg of compost in 25 m2 pond. Production of compost included solid compost and liquid compost. Nutrient concentration of solid compost was ranged from 0.47-0.52% for N; 0.36-0.44% for P; and 5.45-6.39% for organic C, while liquid compost provided 0.62-0.69%; 0.24-0.32%; and 3.98-4.45% respectively for N, P and organic C. While C/N ratio was ranged from 11.60-12.78 and 5.77-7.18 respectively for solid and liquid compost. Solid compost quality resulted that N, P and C/N ration had fulfilled the standart criteria defined by Indonesia National Standart for compost. Observed impact of compost application on pond water quality were the improvement of water clarity and increasing abundance of klekap (lab-lab). This showed that mangrove litters could be converted into a more productive materials to enhance pond environment quality and productivity, decrease management cost and increase benefit. Scheduled fertilization with compost is suggested to be conducted to provide best benefit on silvofishery management.
Han, Yun; Zhuo, Yang; Peng, Dangcong; Yao, Qian; Li, Huijuan; Qu, Qiliang
2017-11-01
The study evaluated the influence of thermal hydrolysis pretreatment (THP) on anaerobic digestion (AD) ability of high solid sludge. The transformation characteristics of organics during the THP+AD process of dewatering sludge from wastewater treatment plant was investigated using a lab-scale THP reactor and four anaerobic digesters. The reduction efficiency of volatile suspended solids using THP+AD exceeded 49%. The acceleration of biogas production during AD was due to the enhancement of protein hydrolysis and acidogenesis by THP. THP had only minimal influence on the improvement of carbohydrate acidogenesis. The hydrolysis of poly phosphates was likely the main reaction of phosphorus transformation. Biochemical generation of sulfide and ammonia nitrogen occurred during the acidogenesis. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Wang, Ruofan; Sun, Zhihao; Pal, Uday B.; Gopalan, Srikanth; Basu, Soumendra N.
2018-02-01
Chromium poisoning is one of the major reasons for cathode performance degradation in solid oxide fuel cells (SOFCs). To mitigate the effect of Cr-poisoning, a protective coating on the surface of interconnect for suppressing Cr vaporization is necessary. Among the various coating materials, Cu-Mn spinel coating is considered to be a potential candidate due to their good thermal compatibility, high stability and good electronic conductivity at high temperature. In this study, Crofer 22 H meshes with no protective coating, those with commercial CuMn2O4 spinel coating and the ones with lab-developed CuMn1.8O4 spinel coating were investigated. The lab-developed CuMn1.8O4 spinel coating were deposited on Crofer 22 H mesh by electrophoretic deposition and densified by a reduction and re-oxidation process. With these different Crofer 22 H meshes (bare, CuMn2O4-coated, and CuMn1.8O4-coated), anode-supported SOFCs with Sr-doped LaMnO3-based cathode were electrochemically tested at 800 °C for total durations of up to 288 h. Comparing the mitigating effects of the two types of Cu-Mn spinel coatings on Cr-poisoning, it was found that the performance of the denser lab-developed CuMn1.8O4 spinel coating was distinctly better, showing no degradation in the cell electrochemical performance and significantly less Cr deposition near the cathode/electrolyte interface after the test.
Dynamically polarized target for the g {2/ p } and G {/E p } experiments at Jefferson Lab
NASA Astrophysics Data System (ADS)
Pierce, J.; Maxwell, J.; Keith, C.
2014-01-01
Recently, two experiments were concluded in Hall A at Jefferson Lab which utilized a newly assembled, solid, polarized hydrogen target. The primary components of the target are a new, high cooling power 4He evaporation refrigerator, and a re-purposed, superconducting split-coil magnet. It has been used to polarize protons in irradiated NH3 at a temperature of 1 K and at fields of 2.5 and 5.0 tesla. Maximum polarizations of 55% and 95% were obtained at those fields, respectively. To satisfy the requirements of both experiments, the magnet had to be routinely rotated between angles of 0°, 6°, and 90° with respect to the incident electron beam.
Well Monitoring System For EGS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Normann, Randy; Glowka, Dave; Normann, Charles
This grant is a collection of projects designed to move aircraft high temperature electronics technology into the geothermal industry. Randy Normann is the lead. He licensed the HT83SNL00 chip from Sandia National Labs. This chip enables aircraft developed electronics for work within a geothermal well logging tool. However, additional elements are needed to achieve commercially successful logging tools. These elements are offered by a strong list of industrial partners on this grant as: Electrochemical Systems Inc. for HT Rechargeable Batteries, Frequency Management Systems for 300C digital clock, Sandia National Labs for experts in high temperature solder, Honeywell Solid-State Electronics Centermore » for reprogrammable high temperature memory. During the course of this project MagiQ Technologies for high temperature fiber optics.« less
Research on Modeling Technology of Virtual Robot Based on LabVIEW
NASA Astrophysics Data System (ADS)
Wang, Z.; Huo, J. L.; Y Sun, L.; Y Hao, X.
2017-12-01
Because of the dangerous working environment, the underwater operation robot for nuclear power station needs manual teleoperation. In the process of operation, it is necessary to guide the position and orientation of the robot in real time. In this paper, the geometric modeling of the virtual robot and the working environment is accomplished by using SolidWorks software, and the accurate modeling and assembly of the robot are realized. Using LabVIEW software to read the model, and established the manipulator forward kinematics and inverse kinematics model, and realized the hierarchical modeling of virtual robot and computer graphics modeling. Experimental results show that the method studied in this paper can be successfully applied to robot control system.
A study was initiated by the EPA/ORD National Exposure Research Lab (NERL) in FY05 to quantify risk reduction resulting from this national EPA initiative to reduce WMPC disposal. Using the 3MRA modeling system, which was recommended for use by the EPA Science Advisory Board for ...
Improved LCI profile of LAB based on latest technology advances
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berna, J.L.; Renta, C.
1995-12-31
The first technology used to produce LAB was introduced in the early 60`s and since then a continuous optimization process has taken place on this highly competitive product on which additional cost effectiveness improvements became highly challenging. The latest technology introduced in the market (CEPSA {minus} UOP DETAL) based on a fixed bed alkylation process, has already been proved on a commercial scale. The simplicity of the new technology as compared to current ones, namely HF, has proven to be very effective in reducing substantially the impact due to several major components of the Life Cycle Inventory (LCI) in particularmore » the emissions of the overall operation. Additional improvements in other aspects like energy consumption are extremely difficult to achieve today as this parameter has already been highly optimized during the last two decades making in fact LAB a highly effective chemical in terms of energy requirements as well as on raw material consumption. The results of the first LCI of the new LAB technology indicate a reduction of CO process emissions to nearly 1/2 as compared to standard HF process as well as reduction in solid waste to 1/3 of the corresponding HF process. Important reductions have also been noticed on NOx emissions with the new technology.« less
Hrad, Marlies; Gamperling, Oliver; Huber-Humer, Marion
2013-10-01
Sustainable landfilling has become a fundamental objective in many modern waste management concepts. In this context, the in situ aeration of landfills has been recognised for its potential to convert conventional anaerobic landfills into biological stabilised state, whereby both current and potential (long-term) emissions of the landfilled waste are mitigated. In recent years, different in situ aeration concepts have been successfully applied in Europe, North America and Asia, all pursuing different objectives and strategies. In Austria, the first full-scale application of in situ landfill aeration by means of low pressure air injection and simultaneous off-gas collection and treatment was implemented on an old, small municipal solid waste (MSW) landfill (2.6ha) in autumn 2007. Complementary laboratory investigations were conducted with waste samples taken from the landfill site in order to provide more information on the transferability of the results from lab- to full-scale aeration measures. In addition, long-term emission development of the stabilised waste after aeration completion was assessed in an ongoing laboratory experiment. Although the initial waste material was described as mostly stable in terms of the biological parameters gas generation potential over 21days (GP21) and respiration activity over 4days (RA4), the lab-scale experiments indicated that aeration, which led to a significant improvement of leachate quality, was accompanied by further measurable changes in the solid waste material under optimised conditions. Even 75weeks after aeration completion the leachate, as well as gaseous emissions from the stabilised waste material, remained low and stayed below the authorised Austrian discharge limits. However, the application of in situ aeration at the investigated landfill is a factor 10 behind the lab-based predictions after 3years of operation, mainly due to technical limitations in the full-scale operation (e.g. high air flow resistivity due to high water content of waste and temporarily high water levels within the landfill; limited efficiency of the aeration wells). In addition, material preparation (e.g. sieving, sorting and homogenisation) prior to the emplacement in Landfill Simulation Reactors (LSRs) must be considered when transferring results from lab- to full-scale application. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Poniger, S. S.; Tochon-Danguy, H. J.; Panopoulos, H. P.; O'Keefe, G. J.; Peake, D.; Rasool, R.; Scott, A. M.
2012-12-01
There is worldwide growing interest for the production of long-lived positron emitters for molecular imaging and the development of novel immuno-PET techniques for drugs discovery. The desire to produce solid target isotopes in Australia has significantly increased over the years and several research projects for labelling of peptides, proteins and biomolecules, including labelling of recombinant antibodies has been limited due to the availability of suitable isotopes. This has led to the recent installation and commissioning of a new lab dedicated to fully automated solid target isotope production, including 124I, 64Cu, 89Zr and 86Y.
Usack, Joseph G; Spirito, Catherine M; Angenent, Largus T
2012-07-13
Anaerobic digestion (AD) is a bioprocess that is commonly used to convert complex organic wastes into a useful biogas with methane as the energy carrier. Increasingly, AD is being used in industrial, agricultural, and municipal waste(water) treatment applications. The use of AD technology allows plant operators to reduce waste disposal costs and offset energy utility expenses. In addition to treating organic wastes, energy crops are being converted into the energy carrier methane. As the application of AD technology broadens for the treatment of new substrates and co-substrate mixtures, so does the demand for a reliable testing methodology at the pilot- and laboratory-scale. Anaerobic digestion systems have a variety of configurations, including the continuously stirred tank reactor (CSTR), plug flow (PF), and anaerobic sequencing batch reactor (ASBR) configurations. The CSTR is frequently used in research due to its simplicity in design and operation, but also for its advantages in experimentation. Compared to other configurations, the CSTR provides greater uniformity of system parameters, such as temperature, mixing, chemical concentration, and substrate concentration. Ultimately, when designing a full-scale reactor, the optimum reactor configuration will depend on the character of a given substrate among many other nontechnical considerations. However, all configurations share fundamental design features and operating parameters that render the CSTR appropriate for most preliminary assessments. If researchers and engineers use an influent stream with relatively high concentrations of solids, then lab-scale bioreactor configurations cannot be fed continuously due to plugging problems of lab-scale pumps with solids or settling of solids in tubing. For that scenario with continuous mixing requirements, lab-scale bioreactors are fed periodically and we refer to such configurations as continuously stirred anaerobic digesters (CSADs). This article presents a general methodology for constructing, inoculating, operating, and monitoring a CSAD system for the purpose of testing the suitability of a given organic substrate for long-term anaerobic digestion. The construction section of this article will cover building the lab-scale reactor system. The inoculation section will explain how to create an anaerobic environment suitable for seeding with an active methanogenic inoculum. The operating section will cover operation, maintenance, and troubleshooting. The monitoring section will introduce testing protocols using standard analyses. The use of these measures is necessary for reliable experimental assessments of substrate suitability for AD. This protocol should provide greater protection against a common mistake made in AD studies, which is to conclude that reactor failure was caused by the substrate in use, when really it was improper user operation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Islam, M.R., E-mail: mrislam1985@yahoo.com; Joardder, M.U.H.; Hasan, S.M.
2011-09-15
In this study on the basis of lab data and available resources in Bangladesh, feasibility study has been carried out for pyrolysis process converting solid tire wastes into pyrolysis oils, solid char and gases. The process considered for detailed analysis was fixed-bed fire-tube heating pyrolysis reactor system. The comparative techno-economic assessment was carried out in US$ for three different sizes plants: medium commercial scale (144 tons/day), small commercial scale (36 tons/day), pilot scale (3.6 tons/day). The assessment showed that medium commercial scale plant was economically feasible, with the lowest unit production cost than small commercial and pilot scale plants formore » the production of crude pyrolysis oil that could be used as boiler fuel oil and for the production of upgraded liquid-products.« less
The Crystallization Clinic-A TA Orientation Exercise
NASA Astrophysics Data System (ADS)
Kandel, Marjorie
1999-01-01
Our orientation exercise for TAs in the organic laboratories is a Crystallization Clinic, and the main feature is a contest. Each TA has a different unknown solid to recrystallize. The products are judged by the students in the organic lab courses. Beauty of the crystals is the single criterion. The contest serves to refresh the TAs' technique and to give them empathy with the beginning students.
Inorganic Nanotubes and Fullerene-Like Nanoparticles:. from the Lab to the Market Place
NASA Astrophysics Data System (ADS)
Tenne, R.
2013-05-01
Layered compounds, like MoS2 were shown by the author to be unstable in the nano-regime. Using new chemical strategies, closed-cage hollow nanostructures in the form of inorganic fullerene-like nanoparticles and inorganic nanotubes were synthesized. These nanostructures exhibit numerous interesting physico-chemical properties and are employed as superior solid lubricants, with numerous other applications currently being developed.
Kinetic modelling of anaerobic hydrolysis of solid wastes, including disintegration processes.
García-Gen, Santiago; Sousbie, Philippe; Rangaraj, Ganesh; Lema, Juan M; Rodríguez, Jorge; Steyer, Jean-Philippe; Torrijos, Michel
2015-01-01
A methodology to estimate disintegration and hydrolysis kinetic parameters of solid wastes and validate an ADM1-based anaerobic co-digestion model is presented. Kinetic parameters of the model were calibrated from batch reactor experiments treating individually fruit and vegetable wastes (among other residues) following a new protocol for batch tests. In addition, decoupled disintegration kinetics for readily and slowly biodegradable fractions of solid wastes was considered. Calibrated parameters from batch assays of individual substrates were used to validate the model for a semi-continuous co-digestion operation treating simultaneously 5 fruit and vegetable wastes. The semi-continuous experiment was carried out in a lab-scale CSTR reactor for 15 weeks at organic loading rate ranging between 2.0 and 4.7 gVS/Ld. The model (built in Matlab/Simulink) fit to a large extent the experimental results in both batch and semi-continuous mode and served as a powerful tool to simulate the digestion or co-digestion of solid wastes. Copyright © 2014 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sajeena Beevi, B., E-mail: sajeenanazer@gmail.com; Madhu, G., E-mail: profmadhugopal@gmail.com; Sahoo, Deepak Kumar, E-mail: dksahoo@gmail.com
2015-02-15
Highlights: • Performance of the reactor was evaluated by the degradation of volatile solids. • Biogas yield at the end of the digestion was 52.9 L/kg VS. • Value of reaction rate constant, k, obtained was 0.0249 day{sup −1}. • During the digestion 66.7% of the volatile solid degradation was obtained. - Abstract: Anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW) is promoted as an energy source and waste disposal. In this study semi dry anaerobic digestion of organic solid wastes was conducted for 45 days in a lab-scale batch experiment for total solid concentration ofmore » 100 g/L for investigating the start-up performances under thermophilic condition (50 °C). The performance of the reactor was evaluated by measuring the daily biogas production and calculating the degradation of total solids and the total volatile solids. The biogas yield at the end of the digestion was 52.9 L/kg VS (volatile solid) for the total solid (TS) concentration of 100 g/L. About 66.7% of the volatile solid degradation was obtained during the digestion. A first order model based on the availability of substrate as the limiting factor was used to perform the kinetic studies of batch anaerobic digestion system. The value of reaction rate constant, k, obtained was 0.0249 day{sup −1}.« less
Experimental constraints on the degree of melting beneath tectonic plates
NASA Astrophysics Data System (ADS)
Clark, A. N.; Lesher, C. E.
2017-12-01
Determining the volume and geometric distribution of silicate melts is fundamentally important to understand the current structure of the Earth as well as the dynamics of the Earth's interior. Regions in the upper mantle and crust that have lower velocities than the 1D global average are commonly attributed to the presence of silicate melts. Constraining melt fraction and distribution from seismic data requires a robust equation of state for silicate melts. Commonly, silicate melts are modeled at high pressure using equations of state developed for crystalline materials (e.g. the Birch-Murnaghan equation of state). However, amorphous silicates (glasses and melts), which lack long-range ordering, violate Birch's law at high pressures and high temperatures (Clark et al., 2016). We present a new model for seismic velocity reductions that accounts for the violation of Birch's law (anomalous compressibility) observed in amorphous silicates, rendering compressional wave velocities more sensitive to melt fraction and distribution than previous estimates. Forward modeling that combines our experimental data with the analytical solution of Takei (2002) predicts comparable velocity reductions for compressional and shear waves for partially molten mantle. Additionally, models that use crystalline equations of state to determine melt fraction at high pressure may overestimate melt fraction by 20% at pressures corresponding to the lithosphere-asthenosphere boundary (LAB) with the overestimation increasing with depth (e.g. a factor of 2 at the transition zone). By applying our results to recent seismic studies below the western Pacific plate that have reported low velocity regions associated with the lithosphere - asthenosphere boundary (LAB), we predict melt present at <5% distributed in near-textural equilibrium. These findings reconcile seismic observations for the LAB regionally and locally, and favor models of strong coupling across the LAB rather than melt channeling due to shear deformation. Clark, A. N., Lesher, C. E., Jacobsen, S. D., and Wang, Y., 2016, Journal of Geophysical Research: Solid Earth, v. 121, no. 6, p. 4232-4248. Takei, Y., 2002, Journal of Geophysical Research: Solid Earth (1978-2012), v. 107, no. B2, p. 6-12.
Ayoib, Adilah; Hashim, Uda; Gopinath, Subash C B; Md Arshad, M K
2017-11-01
This review covers a developmental progression on early to modern taxonomy at cellular level following the advent of electron microscopy and the advancement in deoxyribonucleic acid (DNA) extraction for expatiation of biological classification at DNA level. Here, we discuss the fundamental values of conventional chemical methods of DNA extraction using liquid/liquid extraction (LLE) followed by development of solid-phase extraction (SPE) methods, as well as recent advances in microfluidics device-based system for DNA extraction on-chip. We also discuss the importance of DNA extraction as well as the advantages over conventional chemical methods, and how Lab-on-a-Chip (LOC) system plays a crucial role for the future achievements.
NASA Astrophysics Data System (ADS)
Melanie, Hakiki; Susilowati, Agustine; Maryati, Yati
2017-01-01
Inulin hydrolysate is a result of inulin hydrolysis by inulinase enzyme of Scopulariopsis sp.-CBS1 fungi isolated from dahlia tuber skin in the formation of fructooligosaccharides (FOS) as dietary fiber. Inulin hydrolysate fermented by Bifidobacterium breve has a potential as cholesterol binder in digestive system due to dietary fiber content in inulin. This study was conducted to evaluate the best cholesterol binding capacity by the variation of lactic acid bacteria (LAB) culture concentration of 10%, 20% and 30% (v/v), respectively. Fermentation process were conducted with inulin hydrolysate concentration of 25% (w/v), skim milk 7,5% (w/v) and various LAB culture concentration at 40 °C for 0, 12, 24, 36 and 48 hours. The results showed that the variation of LAB culture concentrations affect the cholesterol binding ability in fermented inulin hydrolysate. The fermentation process with 10% LAB culture concentration at 40°C for 48 hours resulted in the highest cholesterol binding capacity (CBC) of 13,69 mg/g at pH 7and 14,44 mg/g at pH 2 with composition of total acids of 0,787%, soluble dietary fiber of 0,396%, insoluble dietary fiber of 5,47%, total solids of 14,476%, total sugars of 472,484 mg/mL, reducing sugar of 92 mg/mL and total plate count (TPC) of 7,278 log CFU/mL, respectively.
3D Printed Fluidic Hardware for DNA Assembly
2015-04-10
A3909 stepper motor driver, were soldered onto the milled circuit board (Supplementary Figure 8). Custom Arduino - based firmware was written to take...initiatives such as the FabLab Foundation10. Access to digital fabrication tools and open electronics, such as Arduino and Raspberry Pi, enables access to...hardware for assembly of DNA- based genetic circuits. Solid-phase DNA synthesis has declined in price, enabling researchers to routinely design and
The Mineralogy of Comet Wild 2
NASA Technical Reports Server (NTRS)
Zolensky, Michael
2007-01-01
The nature of cometary solids is of fundamental importance to our understanding of the early solar nebula and protoplanetary history. Samples of Comet Wild 2, provided by the Stardust Mission, have now been examined in terrestrial labs for two years, and are very surprising! Here we describe mainly the critical phases olivine, pyroxene and Fe-Ni sulfides in Wild 2 grains, as a guide to the general mineralogy of the returned comet samples.
Wide-field Imaging System and Rapid Direction of Optical Zoom (WOZ)
2010-12-24
The modeling tools are based on interaction between three commercial software packages: SolidWorks, COMSOL Multiphysics, and ZEMAX optical design...deformation resulting from the applied voltages. Finally, the deformed surface can be exported to ZEMAX via MatLab. From ZEMAX , various analyses can...results to extract from ZEMAX to support the optimization remains to be determined. Figure 1 shows the deformation calculated using a model of an
Student Misconceptions and the Conservation of Energy
ERIC Educational Resources Information Center
Froehle, Peter; Miller, Charles H.
2012-01-01
An interesting, quick, and inexpensive lab that we do with our students is to tape one end of a string just less than halfway around the back side of a uniform solid cylinder m[subscript 1] and attach the other end of the string to a mass m[subscript 2] that is below a pulley (Fig. 1). Data can be collected using either an Ultra Pulley (Fig. 2) or…
Kim, Myoung-Ho; Choi, Suk-Jung
2015-04-15
In this study, we devised a stationary liquid-phase lab-on-a-chip (SLP LOC), which was operated by moving solid-phase magnetic particles in the stationary liquid phase. The SLP LOC consisted of a sample chamber to which a sample and reactants were added, a detection chamber containing enzyme substrate solution, and a narrow channel connecting the two chambers and filled with buffer. As a model system, competitive immunoassays of saxitoxin (STX), a paralytic shellfish toxin, were conducted in the SLP LOC using protein G-coupled magnetic particles (G-MPs) as the solid phase. Anti-STX antibodies, STX-horseradish peroxidase conjugate, G-MPs, and a STX sample were added to the sample chamber and reacted by shaking. While liquids were in the stationary state, G-MPs were transported from the sample chamber to the detection chamber by moving a magnet below the LOC. After incubation to allow the enzymatic reaction to occur, the absorbance of the detection chamber solution was found to be reciprocally related to the STX concentration of the sample. Thus, the SLP LOC may represent a novel, simple format for point-of-care testing applications of enzyme-linked immunosorbent assays by eliminating complicated liquid handling steps. Copyright © 2014 Elsevier B.V. All rights reserved.
Hung, Tran Quang; Chin, Wai Hoe; Sun, Yi; Wolff, Anders; Bang, Dang Duong
2017-04-15
Solid-phase PCR (SP-PCR) has become increasingly popular for molecular diagnosis and there have been a few attempts to incorporate SP-PCR into lab-on-a-chip (LOC) devices. However, their applicability for on-line diagnosis is hindered by the lack of sensitive and portable on-chip optical detection technology. In this paper, we addressed this challenge by combining the SP-PCR with super critical angle fluorescence (SAF) microlens array embedded in a microchip. We fabricated miniaturized SAF microlens array as part of a microfluidic chamber in thermoplastic material and performed multiplexed SP-PCR directly on top of the SAF microlens array. Attribute to the high fluorescence collection efficiency of the SAF microlens array, the SP-PCR assay on the LOC platform demonstrated a high sensitivity of 1.6 copies/µL, comparable to off-chip detection using conventional laser scanner. The combination of SP-PCR and SAF microlens array allows for on-chip highly sensitive and multiplexed pathogen detection with low-cost and compact optical components. The LOC platform would be widely used as a high-throughput biosensor to analyze food, clinical and environmental samples. Copyright © 2016 Elsevier B.V. All rights reserved.
Task 3 - Pyrolysis of Plastic Waste. Semiannual report, November 1, 1996--March 31, 1997
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ness, Robert O.; Aulich, Ted R.
1997-12-31
Over the last 50 years, the U.S. Department of Energy (DOE) has produced a wide variety of radioactive wastes from activities associated with nuclear defense and nuclear power generation. These wastes include low-level radioactive solid wastes, mixed wastes, and transuranic (TRU) wastes. A portion of these wastes consists of high- organic-content materials, such as resins, plastics, and other polymers; synthetic and natural rubbers; cellulosic-based materials; and oils, organic solvents, and chlorinated organic solvents. Many of these wastes contain hazardous and/or pyrophoric materials in addition to radioactive species. Physical forms of the waste include ion-exchange resins used to remove radioactive elementsmore » from nuclear reactor cooling water, lab equipment and tools (e.g., measurement and containment vessels, hoses, wrappings, equipment coverings and components, and countertops), oil products (e.g., vacuum pump and lubrication oils), bags and other storage containers (for liquids, solids, and gases), solvents, gloves, lab coats and anti-contamination clothing, and other items. Major polymer and chemical groups found in high-organic-content radioactive wastes include polyvinyl chloride (PVC), low-density polyethylene (LDPE), polypropylene (PP), Teflon(TM), polystyrene (PS), nylon, latex, polyethylene terephthalate (PET), vinyl, high-density polyethylene (HDPE), polycarbonate, nitriles, Tygon(R), butyl, and Tyvec(R).« less
Cobbledick, Jeffrey; Zhang, Victor; Rollings-Scattergood, Sasha; Latulippe, David R
2017-11-01
There is considerable interest in recuperative thickening (RT), the recycling of partially digested solids in an anaerobic digester outlet stream back into the incoming feed, as a 'high-performance' process to increase biogas production, increase system capacity, and improve biosolids stabilization. While polymer flocculation is commonly used in full-scale RT operations, no studies have investigated the effect of flocculation conditions on RT process performance. Our goal was to investigate the effect of polymer type and dosage conditions on dewatering performance and biogas production in a lab-scale RT system. The type of polymer flocculant significantly affected dewatering performance. For example, the 440 LH polymer (low molecular weight (MW) polyacrylamide) demonstrated lower capillary suction time (CST) and filtrate total suspended solids (TSS) values than the C-6267 polymer (high MW polyacrylamide). An examination of the dewatering performance of RT digesters with different polymers found a strong correlation between CST and filtrate TSS. The type of polymer flocculant had no significant effect on biogas productivity or composition; the methane content was greater than 60% in good agreement with typical results. The optimization of the polymer flocculation conditions is a critical task for which the lab-scale RT system used in this work is ideally suited.
Detector development for Jefferson Lab's 12GeV Upgrade
Qiang, Yi
2015-05-01
Jefferson Lab will soon finish its highly anticipated 12 GeV Upgrade. With doubled maximum energy, Jefferson Lab’s Continuous Electron Beam Accelerator Facility (CEBAF) will enable a new experimental program with substantial discovery potential, addressing important topics in nuclear, hadronic and electroweak physics. In order to take full advantage of the high energy, high luminosity beam, new detectors are being developed, designed and constructed to fit the needs of different physics topics. The paper will give an overview of various new detector technologies to be used for 12 GeV experiments. It will then focus on the development of two solenoid-based spectrometers,more » the GlueX and SoLID spectrometers. The GlueX experiment in Hall D will study the complex properties of gluons through exotic hybrid meson spectroscopy. The GlueX spectrometer, a hermetic detector package designed for spectroscopy and the associated partial wave analysis, is currently in the final stage of construction. Hall A, on the other hand, is developing the SoLID spectrometer to capture the 3D image of the nucleon from semi-inclusive processes and to study the intrinsic properties of quarks through mirror symmetry breaking. Such a spectrometer will have the capability to handle very high event rates while still maintaining a large acceptance in the forward region.« less
Enhancing Modulation of Thermal Conduction in Vanadium Dioxide Thin Film by Nanostructured Nanogaps
Choe, Hwan Sung; Suh, Joonki; Ko, Changhyun; ...
2017-08-02
Efficient thermal management at the nanoscale is important for reducing energy consumption and dissipation in electronic devices, lab-on-a-chip platforms and energy harvest/conversion systems. For many of these applications, it is much desired to have a solid-state structure that reversibly switches thermal conduction with high ON/OFF ratios and at high speed. We describe design and implementation of a novel, all-solid-state thermal switching device by nanostructured phase transformation, i.e., modulation of contact pressure an d area between two poly-silicon surfaces activated by microstructural change of a vanadium dioxide (VO 2 ) thin film. Our solid-state devices demonstrate large and reversible alteration ofmore » cross-plane thermal conductance as a function of temperature, achieving a conductance ratio of at least 2.5. This new approach using nanostructured phase transformation provides new opportunities for applications that require advanced temperature and heat regulations.« less
Enhancing Modulation of Thermal Conduction in Vanadium Dioxide Thin Film by Nanostructured Nanogaps
DOE Office of Scientific and Technical Information (OSTI.GOV)
Choe, Hwan Sung; Suh, Joonki; Ko, Changhyun
Efficient thermal management at the nanoscale is important for reducing energy consumption and dissipation in electronic devices, lab-on-a-chip platforms and energy harvest/conversion systems. For many of these applications, it is much desired to have a solid-state structure that reversibly switches thermal conduction with high ON/OFF ratios and at high speed. We describe design and implementation of a novel, all-solid-state thermal switching device by nanostructured phase transformation, i.e., modulation of contact pressure an d area between two poly-silicon surfaces activated by microstructural change of a vanadium dioxide (VO 2 ) thin film. Our solid-state devices demonstrate large and reversible alteration ofmore » cross-plane thermal conductance as a function of temperature, achieving a conductance ratio of at least 2.5. This new approach using nanostructured phase transformation provides new opportunities for applications that require advanced temperature and heat regulations.« less
Measurement system for determination of current-voltage characteristics of PV modules
NASA Astrophysics Data System (ADS)
Idzkowski, Adam; Walendziuk, Wojciech; Borawski, Mateusz; Sawicki, Aleksander
2015-09-01
The realization of a laboratory stand for testing photovoltaic panels is presented here. The project of the laboratory stand was designed in SolidWorks software. The aim of the project was to control the electrical parameters of a PV panel. For this purpose a meter that measures electrical parameters i.e. voltage, current and power, was realized. The meter was created with the use of LabJack DAQ device and LabVIEW software. The presented results of measurements were obtained in different conditions (variable distance from the source of light, variable tilt angle of the panel). Current voltage characteristics of photovoltaic panel were created and all parameters could be detected in different conditions. The standard uncertainties of sample voltage, current, power measurements were calculated. The paper also gives basic information about power characteristics and efficiency of a solar cell.
Rotationally resolved fluorescence spectroscopy of molecular iodine
NASA Astrophysics Data System (ADS)
Lemon, Christopher; Canagaratna, Sebastian; Gray, Jeffrey
2008-03-01
Vibration-electronic spectroscopy of I2 vapor is a common, important experiment in physical chemistry lab courses. We use narrow bandwidth diode-pumped solid state (DPSS) lasers to excite specific rotational levels; these lasers are surprisingly stable and are now available at low cost. We also use efficient miniature fiber-optic spectrometers to resolve rotational fluorescence patterns in a vibrational progression. The resolution enables thorough and accurate analysis of spectroscopic constants for the ground electronic state. The high signal-to-noise ratio, which is easily achieved, also enables students to precisely measure fluorescence band intensities, providing further insight into vibrational wavefunctions and the molecular potential function. We will provide a detailed list of parts for the apparatus as well as modeling algorithms with statistical evaluation to facilitate widespread adoption of these experimental improvements by instructors of intermediate and advanced lab courses.
2001-01-03
KENNEDY SPACE CENTER, Fla. -- Resting atop the Mobile Launcher Platform, Space Shuttle Atlantis is viewed from a high level on the Fixed Service Structure. Seen is one of its solid rocket boosters and the external tank. Next to the wing of the orbiter is one of two tail service masts, which support the fluid, gas and electrical requirements of the orbiter’s liquid oxygen and liquid hydrogen aft T-0 umbilicals. On the horizon is the Atlantic Ocean. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station, carrying the U.S. Laboratory, named Destiny. The lab has five system racks already installed inside the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch no earlier than Jan. 19, 2001, with a crew of five
The protein and peptide mediated syntheses of non-biologically-produced oxide materials
NASA Astrophysics Data System (ADS)
Dickerson, Matthew B.
Numerous examples exist in nature of organisms which have evolved the ability to produce sophisticated structures composed of inorganic minerals. Studies of such biomineralizing organisms have suggested that specialized biomolecules are, in part, responsible for the controlled formation of these structures. The research detailed in this dissertation is focused on the use of biomolecules (i.e., peptides and proteins) to form non-biologically produced materials under mild reaction conditions (i.e., neutral pH, aqueous solutions, and room temperature). The peptides utilized in the studies detailed in this dissertation were identified through the screening of single crystal rutile TiO2 substrates or Ge powder with a phagedisplayed peptide library. Twenty-one peptides were identified which possessed an affinity for Ge. Three of these twenty one peptides were tested for germania precipitation activity. Those peptides possessing a basic isoelectric point as well as hydroxyl- and imidazole-containing amino acid residues were found to be the most effective in precipitating amorphous germania from an alkoxide precursor. The phage-displayed peptide library screening of TiO2 substrates yielded twenty peptides. Four of these peptides, which were heavily enriched in histidine and/or basic amino acid residues, were found to possess signficant titania precipitation activity. The activity of these peptides was found to correlate with the number of positive charges they carried. The sequence of the most active of the library-identified peptides was modified to yield two additional peptides. The titania precipitation activity of these designed peptides was higher than the parent peptide, with reduced pH dependence. The titania materials generated by the library-identified and designed peptides were found to be composed of amorphous titania as well as <10 nm anatase and/or monoclinic TiO2 crystallites. The production of titania and zirconia resulting from the interaction of the cationic enzyme, hen egg white lysozyme, with Ti- or Zr-lactate precursors is also presented in this dissertation. Lysozyme was found to entrap itself in an active form within the nanoparticles of amorphous titania or zirconia precipitated by this protein under ambient conditions. The lysozyme synthesized titania was observed to be superior to the lysozyme-zirconia materials in preserving the activity of the enzyme under denaturing conditions. Four recombinant proteins, derived from the amino acid sequences of proteins (silaffins) associated with biosilicification in diatoms, were also investigated for titania precipitation activity. The two most basic of these recombinant silaffins, rSil1L and rSilC, were able to induce the formation of titania. The titania precipitates generated by rSil1L were found to be similar to those produced by the phage-displayed library identified peptides. The second recombinant silaffin, rSilC, was found to produce hollow spheres of titania, which, following dehydration, were observed to transform into larger, solid spheres composed of radially aligned columns of rutile TiO2. The highly repetitive nature of the rSilC's amino acid sequence is believed to be responsible for the differences in TiO2 polymorph generated by the different recombinant silaffins and peptides. This dissertation also details research conducted on the formation of titania utilizing rSilC conjugated to synthetic and biogenic silica surfaces. These silica surfaces were functionalized with a newly developed drendritic growth technique. The dendritic functional-group amplification process was demonstrated to increase the loading of hexahisitidine tagged proteins on silica surfaces by more than 40%, as compared to traditional immobilization procedures. The higher loadings of rSilC provided by this dendritic growth method were observed to have a positive impact on the extent of surface mineralization. The titania formed by immobilized rSilC was observed to be composed of amorphous and crystalline TiO2.
Bioactive Molecules Released in Food by Lactic Acid Bacteria: Encrypted Peptides and Biogenic Amines
Pessione, Enrica; Cirrincione, Simona
2016-01-01
Lactic acid bacteria (LAB) can produce a huge amount of bioactive compounds. Since their elective habitat is food, especially dairy but also vegetal food, it is frequent to find bioactive molecules in fermented products. Sometimes these compounds can have adverse effects on human health such as biogenic amines (tyramine and histamine), causing allergies, hypertensive crises, and headache. However, some LAB products also display benefits for the consumers. In the present review article, the main nitrogen compounds produced by LAB are considered. Besides biogenic amines derived from the amino acids tyrosine, histidine, phenylalanine, lysine, ornithine, and glutamate by decarboxylation, interesting peptides can be decrypted by the proteolytic activity of LAB. LAB proteolytic system is very efficient in releasing encrypted molecules from several proteins present in different food matrices. Alpha and beta-caseins, albumin and globulin from milk and dairy products, rubisco from spinach, beta-conglycinin from soy and gluten from cereals constitute a good source of important bioactive compounds. These encrypted peptides are able to control nutrition (mineral absorption and oxidative stress protection), metabolism (blood glucose and cholesterol lowering) cardiovascular function (antithrombotic and hypotensive action), infection (microbial inhibition and immunomodulation) and gut-brain axis (opioids and anti-opioids controlling mood and food intake). Very recent results underline the role of food-encrypted peptides in protein folding (chaperone-like molecules) as well as in cell cycle and apoptosis control, suggesting new and positive aspects of fermented food, still unexplored. In this context, the detailed (transcriptomic, proteomic, and metabolomic) characterization of LAB of food interest (as starters, biocontrol agents, nutraceuticals, and probiotics) can supply a solid evidence-based science to support beneficial effects and it is a promising approach as well to obtain functional food. The detailed knowledge of the modulation of human physiology, exploiting the health-promoting properties of fermented food, is an open field of investigation that will constitute the next challenge. PMID:27375596
The national labs and their future
DOE Office of Scientific and Technical Information (OSTI.GOV)
Crease, R.P.
National laboratories of the USA, born with the atomic age and raised to prominence by the need for scientific superiority during the long Cold War, are facing the most critical challenge: how best to support the nation's current need to improve its international competitiveness through superior technology The charge that the national laboratories are [open quotes]Cold War relics[close quotes] that have outlived their usefulness is based on a misunderstanding of their mission, says Robert P. Crease, historian for Brookhaven National laboratory. Three of the labs-Los Alamos, Sandia, and Lawrence Livermore- are weapons laboratories and their missions must change. Oak Ridge,more » Argonne, and Brookhaven laboratories are multipurpose: basic research facilities with a continuing role in the world of science The national laboratory system traces its origins to the Manhattan Project. Over the next half-century, America's national labs grew into part of the most effective scientific establishment in the world, a much-copied model for management of large-scale scientific programs. In the early years, each lab defined a niche in the complex world of reactors, accelerators, and high-energy proton and electron physics. In the 1970s, several labs worked on basic energy sciences to help solve a national energy crisis. Today, the labs are pressured to do more applied research-research to transfer to the private sector and will have to respond by devising more effective ways of coordinating basic and applied research. But, Crease warns, [open quotes]It also will be essential that any commitment to applied research not take place at the cost of reducing the wellspring of basic research from which so much applied research flows. [open quotes]Making a solid and persuasive case for the independent value of basic research, and for their own role in that enterprise, may be the most important task facing the laboratories in their next half-century,[close quotes].« less
Extended Solids of Carbon Monoxide formed from Re2(CO)12
NASA Astrophysics Data System (ADS)
Ciezak-Jenkins, Jennifer
Extended solids are formed from simple molecular gases under extreme P/T and are of considerable interest as high-energy-density materials. It has been postulated that a transformation from a single-bonded polymeric-like material back to the more stable triply-bonded diatomic phase would be a highly exothermic process yielding large amounts of energy. The extended polymeric solid of CO was first reported and recovered from high pressure conditions in 2005. Although the material was found to have potentially interesting energetic properties, it showed a number of stability issues, degrading into CO2 and graphitic carbon over 3 to 5 days. As such, our lab has been focused on the identification of methods to increase the metastability of the recovered solid. Metal carbonyls offer one such route for stabilization. In this talk, our progress in the study of the synthesis, characterization, and recovery of extended solids of CO starting from Re2(CO)12\\ to pressures near 50 GPa will be presented. I will discuss the analysis and the implications of these results. New opportunities and challenges that have arisen in the course of our studies that will be pursued in the future will also be presented. Ref
New Turbulent Multiphase Flow Facilities for Simulation Benchmarking
NASA Astrophysics Data System (ADS)
Teoh, Chee Hau; Salibindla, Ashwanth; Masuk, Ashik Ullah Mohammad; Ni, Rui
2017-11-01
The Fluid Transport Lab at Penn State has devoted last few years on developing new experimental facilities to unveil the underlying physics of coupling between solid-gas and gas-liquid multiphase flow in a turbulent environment. In this poster, I will introduce one bubbly flow facility and one dusty flow facility for validating and verifying simulation results. Financial support for this project was provided by National Science Foundation under Grant Number: 1653389 and 1705246.
Understanding the Femtosecond Laser-Solid Interaction Near and Beyond the Material Damage Threshold
2016-05-23
study of the fundamentals of femtosecond laser damage as a function of various parameters, laser wavelength, pulsewidth, pulse number, experimental ... experimental observation without any free parameters. The brand new FSD Lab constructed under the BRI grant in the Physics Research Building at the Ohio... studied across a range of band-gaps for s- and p-polarized light and it is found that conventional theoretical prediction on laser damage threshold
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kageya, Tsuneo; Ho, Dao; Peng, Peng
E asymmetries have been extracted from double-polarizationexperiments in Hall-B of the Thomas Jefferson National Accelerator Facility (JLab). Results have been obtained from the E06-101 (g14) experiment, using circularly polarized photon beams, longitudinally polarized Deuterons in solid HD targets, and the CEBAF Large Acceptance Spectrometer (CLAS). The results cover a range inW from 1.48 to 2.32 GeV. Three independent analyses, using distinctly different methods, have been combined to obtain the final values, which have been published recently. Partial wave analyses (PWA), which have had to rely on a sparse neutron data base, havebeen significantly changed with the inclusion of these g14more » asymmetries.« less
2008-10-17
CAPE CANAVERAL, Fla. – This photo shows the waste and hygiene compartment that will be delivered to the International Space Station aboard space shuttle Endeavour on the STS-126 mission. The Russian-built toilet system provides the crew with a second facility on the station, located in the Destiny lab. The unit separately channels liquid and solid waste. While the solid waste goes to a holding tank, a new pair of processing units that Endeavour also will deliver on this mission are set to begin a unique recycling program -- turning crew members’ urine into potable water. Space shuttle Endeavour and its crew of seven are scheduled to lift off at 7:55 p.m. Nov. 14 for the 15-day STS-126 mission. Photo credit: NASA
Lateral solids dispersion coefficient in large-scale fluidized beds
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Daoyin; Chen, Xiaoping
2010-11-15
The design of fuel feed ports in a large-scale fluidized bed combustor depends on the fuel characteristics and lateral solids mixing. However, the reported values of the effective lateral solids dispersion coefficient (D{sub sr}) are scattered in the broad range of 0.0001-0.1 m{sup 2}/s. With the aim of predicting D{sub sr} in wider fluidized beds which is difficult to measure directly or deduce from experimental results in lab-scale facilities, a computational method is proposed. It combines the Eulerian-Granular simulation and fictitious particle tracing technique. The value of D{sub sr} is calculated based on the movement of the tracers. The effectmore » on D{sub sr} of bed width (W) ranging from 0.4 m up to 12.8 m at different levels of superficial gas velocity (U{sub 0}) is investigated. It is found that increasing W whilst maintaining U{sub 0}, D{sub sr} initially increases markedly, then its increase rate declines, and finally it stays around a constant value. The computed values of D{sub sr} are examined quantitatively and compared with a thorough list of the measured D{sub sr} in the literature since 1980s. Agreed with the measurements performed in the pilot-scale fluidized beds, the value of D{sub sr} in wider facilities at higher fluidizing velocities is predicted to be around the order of magnitude of 0.1 m{sup 2}/s, much higher than that in lab-scale beds. Finally, the effect of D{sub sr} on the distribution of fuel particles over the cross section in fluidized beds with the specified layout of feed ports is discussed. (author)« less
Watanabe, Masanori; Techapun, Charin; Kuntiya, Ampin; Leksawasdi, Noppol; Seesuriyachan, Phisit; Chaiyaso, Thanongsak; Takenaka, Shinji; Maeda, Isamu; Koyama, Masahiro; Nakamura, Kozo
2017-02-01
A lactic acid producing bacterium, Lactobacillus rhamnosus M-23, newly isolated from a rice washing drainage storage tank was found to produce l-(+)-lactic acid from a non-sterilized mixture of rice washing drainage and rice bran without any additions of nutrients under the simultaneous saccharification and fermentation (SSF) process. This strain has the ability to utilize the non-sterilized rice washing drainage and rice bran as a source of carbohydrate, saccharifying enzymes and nutrients for lactic acid production. Observation of extracellular protease activity in SSF culture broth showed that a higher protease activity was present in strain M-23 than in other isolated lactic acid producing bacteria (LABs). To investigate the structural changes of solid particles of rice washing drainage throughout LAB cultivation, scanning electron microscopic (SEM) observation and Fourier transform infrared-spectroscopy (FT-IR) analysis were performed. The results of the SEM observation showed that the surface material could be removed from solid particles of rice washing drainage treated by culture broth (supernatant) of strain M-23, thus exposing the crystal structure of the starch particle surface. The results of the FT-IR analysis revealed that the specific transmittance decrease of the CC and CO stretching and OH group of the solid particles of the rice washing drainage were highly correlated with the produced lactic acid concentration and extracellular protease activity, respectively. These results demonstrate the high lactic acid producing ability of strain M-23 from a non-sterilized mixture of rice washing drainage and rice bran under the SSF condition due to the removal of proteinaceous material and exposure of the starch particle surface by extracellular protease. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
Physics of sub-micron cosmic dust particles
NASA Technical Reports Server (NTRS)
Roy, N. L.
1974-01-01
Laboratory tests with simulated micrometeoroids to measure the heat transfer coefficient are discussed. Equations for ablation path length for electrically accelerated micrometeoroids entering a gas target are developed which yield guidelines for the laboratory measurement of the heat transfer coefficient. Test results are presented for lanthanum hexaboride (LaB sub 6) microparticles in air, argon, and oxygen targets. The tests indicate the heat transfer coefficient has a value of approximately 0.9 at 30 km/sec, and that it increases to approximately unity at 50 km/sec and above. Test results extend to over 100 km/sec. Results are also given for two types of small particle detectors. A solid state capacitor type detector was tested from 0.61 km/sec to 50 km/sec. An impact ionization type detector was tested from 1.0 to 150 km/sec using LaB sub 6 microparticles.
NASA Astrophysics Data System (ADS)
Bisesto, F. G.; Anania, M. P.; Chiadroni, E.; Cianchi, A.; Costa, G.; Curcio, A.; Ferrario, M.; Galletti, M.; Pompili, R.; Schleifer, E.; Zigler, A.
2017-05-01
Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (> 100 GV/m), enabling acceleration of electrons to GeV energy in few centimeters. Here we present all the plasma related activities currently underway at SPARC LAB exploiting the high power laser FLAME. In particular, we will give an overview of the single shot diagnostics employed: Electro Optic Sampling (EOS) for temporal measurement and optical transition radiation (OTR) for an innovative one shot emittance measurements. In detail, the EOS technique has been employed to measure for the first time the longitudinal profile of electric field of fast electrons escaping from a solid target, driving the ions and protons acceleration, and to study the impact of using different target shapes. Moreover, a novel scheme for one shot emittance measurements based on OTR, developed and tested at SPARC LAB LINAC, will be shown.
NASA Astrophysics Data System (ADS)
Wempe, W.; Spetzler, H.; Kittleson, C.; Pursley, J.
2003-12-01
We observed significant reduction in wetting hysteresis with time while a diesel-contaminated quartz crystal was dipped in and out of an oil-reducing bacteria solution. This wetting hysteresis is significantly greater than the wetting hysteresis when the diesel-contaminated quartz crystal is dipped in and out of (1) water, (2) diesel and (3) the bacterial food solution that does not contain bacteria. The reduction in wetting hysteresis of the bacteria solution on the quartz surface results from a reduction in the advancing contact angle formed at the air-liquid-quartz contact with time; the receding contact angle remains the same with time. Our results suggest that the bacteria solution moves across the quartz surface with less resistance after bioremediation has begun. These results imply that bioremediation may influence fluid flow behavior with time. For many fluid-solid systems there is a difference between the contact angle while a contact line advances and recedes across a solid surface; this difference is known as wetting hysteresis. Changes in wetting hysteresis can occur from changes in surface tension or the surface topography. Low contact angle values indicate that the liquid spreads or wets well, while high values indicate poor wetting or non-wetting. Contact angles are estimated in the lab by measuring the weight of the meniscus formed at the air-liquid-quartz interface and by knowing the fluid surface tension. In the lab, we have been able to use low-frequency seismic attenuation data to detect changes in the wetting characteristics of glass plates and of Berea sandstone. The accepted seismic attenuation mechanism is related to the loss of seismic energy due to the hysteresis of meniscus movement (wetting hysteresis) when a pore containing two fluids is stressed at very low frequencies (< 10 Hz). When fluid-fluid-solid systems that exhibit wettability hysteresis are stressed at low frequencies, we observe seismic attenuation, whereas in a system that does not exhibit wettability hysteresis we do not. From our wettability hysteresis results, we conclude that we may be able to monitor bioremediation progress using seismic attenuation data. We are measuring low-frequency seismic attenuation in the lab while flowing bacteria solution through Berea sandstone and we are testing this application in the field.
1981-08-15
United States Government. The Public Affairs Office has reviewed this report, and it is releasable to the National Technical Information Service, where it...will be available to the general public, including foreign nationals. This technical report has been reviewed and is approved for publication. FOR...n D.. II .. I swat rai~. Bruv,d,~ S( . J.1x,la. L.i),’, It C. ’ . it. -11..... It. Bre,lab. ’ .1. IN. kalaaaaal. H. . M ~ Ia~ ~ . .1. [’aaa. I
Design of a Six Degree of Freedom Thrust Sensor for a Hybrid Rocket
NASA Astrophysics Data System (ADS)
McGehee, Tripp
2005-03-01
A hybrid rocket is composed of a solid fuel and a separate liquid or gaseous oxidizer. These rockets may be throttled like liquid rockets, are safer than solid rockets, and are much less complex than liquid rockets. However, hybrid rockets produce thrust oscillations that are not practical for large scale use. A lab scale hybrid rocket at the University of Arkansas at Little Rock (UALR) Hybrid Rocket Facility is used to develop sensors to measure physical properties of hybrid rockets. Research is currently being conducted to design a six degree of freedom force sensor to measure the thrust and torque in all three spatial dimensions. The current design mounts the rocket in a rigid cage and connects the cage to a solid table by six sensor legs. The legs utilize strain gauges and a Wheatstone bridge to produce a voltage proportional to the force on the leg. A detailed description of the cage design and the design process will be given.
Cocoa residues as viable biomass for renewable energy production through anaerobic digestion.
Acosta, Nayaret; De Vrieze, Jo; Sandoval, Verónica; Sinche, Danny; Wierinck, Isabella; Rabaey, Korneel
2018-05-31
The aim of this work was to evaluate the bioenergy potential of cocoa residue via anaerobic digestion. Batch and fed-batch lab-scale reactors were operated under low and high solids conditions. In the batch tests, 59 ± 4% of Chemical Oxygen Demand (COD) was recovered as methane. This corresponded with an average methane yield of 174 (wet) and 193 (dry) L kg -1 volatile solids fed, whereas a series of fed-batch reactors produced 70 ± 24 (wet) and 107 ± 39 (dry) L CH 4 kg -1 volatile solids fed during stable conditions. A case study was developed for canton Balao (Ecuador) based on our experimental data, operational estimates and available cocoa waste in the area. Annually, 8341 MWh could be produced, meeting 88% of the current electricity demand in Balao. This case study proves the potential for cocoa waste as a source of renewable energy in rural areas. Copyright © 2018 Elsevier Ltd. All rights reserved.
The effect of mixing ratio variation of sludge and organic solid waste on biodrying process
NASA Astrophysics Data System (ADS)
Nasution, A. C.; Kristanto, G. A.
2018-01-01
In this study, organic waste was co-biodried with sludge cake to determine which mixing ratio gave the best result. The organic waste was consisted of dried leaves and green leaves, while the sludge cake was obtained from a waste water treatment plant in Bekasi. The experiment was performed on 3 lab-scale reactors with same specifications. After 21 days of experiment, it was found that the reactor with the lowest mixing fraction of sludge (5:1) has the best temperature profile and highest moisture content depletion compared with others. Initial moisture content and initial volatile solid content of this reactor’s feedstock was 52.25% and 82.4% respectively. The airflow rate was 10 lpm. After biodrying was done, the final moisture content of the feedstock from Reactor C was 22.0% and the final volatile solid content was 75.9%.The final calorific value after biodrying process was 3179,28kcal/kg.
Analysis of the effect of waste's particle size variations on biodrying method
NASA Astrophysics Data System (ADS)
Kristanto, Gabriel Andari; Zikrina, Masayu Nadiya
2017-11-01
The use of municipal solid waste as energy source can be a solution for Indonesia's increasing energy demand. However, its high moisture content limits the use of solid waste as energy. Biodrying is a method of lowering wastes' moisture content using biological process. This study investigated the effect of wastes' particle size variations on biodrying method. The experiment was performed on 3 lab-scale reactors with the same specifications. Organic wastes with the composition of 50% vegetable wastes and 50% garden wastes were used as substrates. The feedstock was manually shredded into 3 size variations, which were 10 - 40 mm, 50 - 80 mm, and 100 - 300 mm. The experiment lasted for 21 days. After 21 days, it was shown that the waste with the size of 100 - 300 mm has the lowest moisture content, which is 50.99%, and the volatile solids content is still 74.3% TS. This may be caused by the higher free air space of the reactor with the bigger sized substrate.
Methods for the preparation and analysis of solids and suspended solids for total mercury
Olund, Shane D.; DeWild, John F.; Olson, Mark L.; Tate, Michael T.
2004-01-01
The methods documented in this report are utilized by the Wisconsin District Mercury Lab for analysis of total mercury in solids (soils and sediments) and suspended solids (isolated on filters). Separate procedures are required for the different sample types. For solids, samples are prepared by room-temperature acid digestion and oxidation with aqua regia. The samples are brought up to volume with a 5 percent bromine monochloride solution to ensure complete oxidation and heated at 50?C in an oven overnight. Samples are then analyzed with an automated flow injection system incorporating a cold vapor atomic fluorescence spectrometer. A method detection limit of 0.3 ng of mercury per digestion bomb was established using multiple analyses of an environmental sample. Based on the range of masses processed, the minimum sample reporting limit varies from 0.6 ng/g to 6 ng/g. Suspended solids samples are oxidized with a 5 percent bromine monochloride solution and held at 50?C in an oven for 5 days. The samples are then analyzed with an automated flow injection system incorporating a cold vapor atomic fluorescence spectrometer. Using a certified reference material as a surrogate for an environmental sample, a method detection limit of 0.059 ng of mercury per filter was established. The minimum sample reporting limit varies from 0.059 ng/L to 1.18 ng/L, depending on the volume of water filtered.
Nanodroplet impact onto solid platinum surface: Spreading and bouncing
NASA Astrophysics Data System (ADS)
Lussier, Daniel; Ventikos, Yiannis
2009-11-01
The impact of droplets onto solid surfaces is found in a huge variety of natural and technological applications, from rain drops splashing on the pavement, to material manufacturing by molten droplet deposition. Taking inspiration from existing microfluidic technologies (i.e. lab-on-chip), there is increasing interest in the use of nanodroplets (D < 100 nm) for a number of applications such as drug delivery and semiconductor device manufacturing. However, as the size of the droplet is reduced into the nanoscale, the direct use of previously obtained macroscopic results is not guaranteed. At the nanoscale, important effects due to the molecular nature of the fluid, thermal fluctuations and reduced dimensionality can play a critical role in determining system dynamics. In this paper we present the results of large-scale, fully atomistic, three-dimensional molecular dynamics (MD) simulation of an argon nanodroplet (D = 18 nm, 54 000 atoms) impact onto a solid platinum surface, using the LAMMPS software package. The fluid argon is modeled using the well-known Lennard-Jones (LJ) potential, while the embedded-atom model (EAM) potential is used for the solid platinum. By varying both the impact velocities (10-1000 m/s) and the wettability of the solid surface a wide range of impact behaviors is observed, from smooth spreading, to bouncing recoil, pointing towards a wide array of potential applications.
Kinetic modelling of anaerobic hydrolysis of solid wastes, including disintegration processes
DOE Office of Scientific and Technical Information (OSTI.GOV)
García-Gen, Santiago; Sousbie, Philippe; Rangaraj, Ganesh
2015-01-15
Highlights: • Fractionation of solid wastes into readily and slowly biodegradable fractions. • Kinetic coefficients estimation from mono-digestion batch assays. • Validation of kinetic coefficients with a co-digestion continuous experiment. • Simulation of batch and continuous experiments with an ADM1-based model. - Abstract: A methodology to estimate disintegration and hydrolysis kinetic parameters of solid wastes and validate an ADM1-based anaerobic co-digestion model is presented. Kinetic parameters of the model were calibrated from batch reactor experiments treating individually fruit and vegetable wastes (among other residues) following a new protocol for batch tests. In addition, decoupled disintegration kinetics for readily and slowlymore » biodegradable fractions of solid wastes was considered. Calibrated parameters from batch assays of individual substrates were used to validate the model for a semi-continuous co-digestion operation treating simultaneously 5 fruit and vegetable wastes. The semi-continuous experiment was carried out in a lab-scale CSTR reactor for 15 weeks at organic loading rate ranging between 2.0 and 4.7 g VS/L d. The model (built in Matlab/Simulink) fit to a large extent the experimental results in both batch and semi-continuous mode and served as a powerful tool to simulate the digestion or co-digestion of solid wastes.« less
Modeling and Control of Algae Harvesting, Dewatering and Drying (HDD) Systems
2012-05-01
The energy is storied in 5 the form of oils, proteins and the others. The algae oils can be made into biodiesel , and biodiesel is gaining public...tested. Results showed that the energy needed to dewater to 20% solids was 6.7 Whrs in 10 minutes based on motor current, while the energy needed to...dewater and dry to ɝ% moisture was 206 Whrs in 10 minutes based on motor /heater current. Furthermore, the AVS HDD Lab System running at 500 L/hr
1998 Physical Acoustics Summer School (PASS 98). Volume 1: Transcripts.
1998-01-01
just simple adiabatic heating , the temperature also goes up a lot. I ask you, if you went back to your lab, built a levitator, put a bubble in there...radial pulsations of the bubble similar to the second graph on Transparency 10. Now turn up the amplitude. The first thing you notice is that the...region called non-spherical pulsations . The bubble is going crazy. Turn the amplitude up more and the bubble stabilizes rock solid, gets really small
2008-03-01
will be accomplished by the day prior to the sample transfer operation. i. The radiation hood lab bench tops where radioactive material will be...source container to a sample container in a single syringe transfer. (All other non- radioactive solutions will have been previously added to this... radioactive spill. 4. Procedure Checklist: a. Setup □ Tape down plastic liner and locate absorbent □ Lay out sample container holder, sample
Isolation and characterization of novel lipases/esterases from a bovine rumen metagenome.
Privé, Florence; Newbold, C Jamie; Kaderbhai, Naheed N; Girdwood, Susan G; Golyshina, Olga V; Golyshin, Peter N; Scollan, Nigel D; Huws, Sharon A
2015-07-01
Improving the health beneficial fatty acid content of meat and milk is a major challenge requiring an increased understanding of rumen lipid metabolism. In this study, we isolated and characterized rumen bacterial lipases/esterases using functional metagenomics. Metagenomic libraries were constructed from DNA extracted from strained rumen fluid (SRF), solid-attached bacteria (SAB) and liquid-associated rumen bacteria (LAB), ligated into a fosmid vector and subsequently transformed into an Escherichia coli host. Fosmid libraries consisted of 7,744; 8,448; and 7,680 clones with an average insert size of 30 to 35 kbp for SRF, SAB and LAB, respectively. Transformants were screened on spirit blue agar plates containing tributyrin for lipase/esterase activity. Five SAB and four LAB clones exhibited lipolytic activity, and no positive clones were found in the SRF library. Fosmids from positive clones were pyrosequenced and twelve putative lipase/esterase genes and two phospholipase genes retrieved. Although the derived proteins clustered into diverse esterase and lipase families, a degree of novelty was seen, with homology ranging from 40 to 78% following BlastP searches. Isolated lipases/esterases exhibited activity against mostly short- to medium-chain substrates across a range of temperatures and pH. The function of these novel enzymes recovered in ruminal metabolism needs further investigation, alongside their potential industrial uses.
Parity Violation in DIS region with SoLID at the upgraded 12 GeV JLab
NASA Astrophysics Data System (ADS)
Tian, Ye; SoLID Collaboration
2017-09-01
In this talk, an overview of PVDIS future experiment by using a Solenoidal Large Intensity Device (SoLID) at Jefferson Lab (JLab) Hall A with the 12 GeV upgrade, along with a brief description of the proposed SoLID spectrometer is discussed. We will obtain data with high statistic and large kinematic coverage for Bjorken 0.3 < x < 0.7 and in the momentum transfer Q2 range 2 - 10 GeV2 by a polarized electron beam scattering on unpolarized deuteron and proton targets. A measurement of PVDIS in deuteron aims to extract fundamental coupling constants C1 q ,C2 q as well as the weak mixing angle sin2θw with a high precision. This measurement can also access QCD physics of searching for charge asymmetry violation in PDF's and higher-twist effects with quark-quark correlations. In addition, the proton target experiment can be a powerful probe of the d / u ratio at high x without any nuclear correction. The designed SoLID spectrometer with its unique feature of high luminosity and large acceptance provides an opportunity to probe physics beyond the Standard Model.
Sun, Zhao-Yong; Zhang, Jing; Zhong, Xiao-Zhong; Tan, Li; Tang, Yue-Qin; Kida, Kenji
2016-05-01
In the present study, we developed an efficient composting process for the solid fraction of dairy manure (SFDM) using lab-scale systems. We first evaluated the factors affecting the SFDM composting process using different thermophilic phase durations (TPD, 6 or 3days) and aeration rates (AR, 0.4 or 0.2 lmin(-1)kg(-1)-total solid (TS)). Results indicated that a similar volatile total solid (VTS) degradation efficiency (approximately 60%) was achieved with a TPD of 6 or 3days and an AR of 0.4 l min(-1) kg(-1)-TS (hereafter called higher AR), and a TPD of 3days resulted in less N loss caused by ammonia stripping. N loss was least when AR was decreased to 0.2 l min(-1) kg(-1)-TS (hereafter called lower AR) during the SFDM composting process. However, moisture content (MC) in the composting pile increased at the lower AR because of water production by VTS degradation and less water volatilization. Reduced oxygen availability caused by excess water led to lower VTS degradation efficiency and inhibition of nitrification. Adding sawdust to adjust the C/N ratio and decrease the MC improved nitrification during the composing processes; however, the addition of increasing amounts of sawdust decreased NO3(-) concentration in matured compost. When an improved composting reactor with a condensate removal and collection system was used for the SFDM composting process, the MC of the composting pile was significantly reduced, and nitrification was detected 10-14days earlier. This was attributed to the activity of ammonia-oxidizing bacteria (AOB). Highly matured compost could be generated within 40-50days. The VTS degradation efficiency reached 62.0% and the final N content, NO3(-) concentration, and germination index (GI) at the end of the composting process were 3.3%, 15.5×10(3)mg kg(-1)-TS, and 112.1%, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.
Belanche, A; de la Fuente, G; Pinloche, E; Newbold, C J; Balcells, J
2012-11-01
Accurate estimates of microbial synthesis in the rumen are vital to optimize ruminant nutrition. Liquid- (LAB) and solid-associated bacterial fractions (SAB) harvested from the rumen are generally considered as microbial references when microbial yield is calculated; however, factors that determine their composition are not completely understood. The aim of this study was to evaluate the effect of diet and absence or presence of rumen protozoa on the rumen microbial community. It was hypothesized that these treatments could modify the composition and representativeness of LAB and SAB. Twenty twin lambs (Ovis aries) were used; one-half of the twins were kept protozoa-free, and each respective twin sibling was faunated. At 6 mo of age, 5 animals from each group were randomly allocated to the experimental diets consisting of either alfalfa hay as the sole diet, or 50:50 mixed with ground barley grain. After 15 d of adaptation to the diet, animals were euthanized, rumen and abomasum contents were sampled, and LAB and SAB isolated. The presence of protozoa buffered the effect of diet on the rumen bacterial population. Faunated animals fed alfalfa hay had a greater abundance of F. succinogenes, anaerobic fungi and methanogens, as well as an enhanced rumen bacterial diversity. Cellulolytic bacteria were more abundant in SAB, whereas the abomasal abundance of most of the microorganisms studied was closer to those values observed in LAB. Rumen and abomasal samples showed similar bacterial DNA concentrations, but the fungal and protozoal DNA concentration in the abomasum was only 69% and 13% of that observed in the rumen, respectively, suggesting fungal and protozoal sequestration in the rumen or possible preferential degradation of fungal and protozoal DNA in the abomasum, or both. In conclusion, absence of protozoa and type of diet extensively modified the chemical composition of LAB and SAB as a consequence of changes in the microbial composition of these fractions.
Vichapong, Jitlada; Burakham, Rodjana; Srijaranai, Supalax; Grudpan, Kate
2011-07-01
A sequential injection-bead injection-lab-on-valve system was hyphenated to HPLC for online renewable micro-solid-phase extraction of carbamate insecticides. The carbamates studied were isoprocarb, methomyl, carbaryl, carbofuran, methiocarb, promecarb, and propoxur. LiChroprep(®) RP-18 beads (25-40 μm) were employed as renewable sorbent packing in a microcolumn situated inside the LOV platform mounted above the multiposition valve of the sequential injection system. The analytes sorbed by the microcolumn were eluted using 80% acetonitrile in 0.1% acetic acid before online introduction to the HPLC system. Separation was performed on an Atlantis C-18 column (4.6 × 150 mm, 5 μm) utilizing gradient elution with a flow rate of 1.0 mL/min and a detection wavelength at 270 nm. The sequential injection system offers the means of performing automated handling of sample preconcentration and matrix removal. The enrichment factors ranged between 20 and 125, leading to limits of detection (LODs) in the range of 1-20 μg/L. Good reproducibility was obtained with relative standard deviations of <0.7 and 5.4% for retention time and peak area, respectively. The developed method has been successfully applied to the determination of carbamate residues in fruit, vegetable, and water samples. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Dielectric properties of Ba0.6Sr0.4TiO3-La(B0.5Ti0.5)O3 (B=Mg, Zn) ceramics.
Xu, Yebin; Liu, Ting; He, Yanyan; Yuan, Xiao
2009-11-01
Ba(0.6)Sr(0.4)TiO(3)-La(B(0.5)Ti(0.5))O(3) (B = Mg, Zn) ceramics were prepared by a solid-state reaction method, and their microwave dielectric characteristics and tunability were investigated. The ferroelectric-dielectric solid solutions with cubic perovskite structures were obtained for compositions of 10 to 60 mol% La(Mg(0.5)Ti(0.5))O(3) and 10 to 50 mol% La(Zn(0.5)Ti(0.5))O(3). With the increase of linear oxide dielectric content, the dielectric constant and tunability were decreased and Qf was increased. Ba(0.6)Sr(0.4)TiO(3)-La(Mg(0.5)Ti(0.5))O(3) has better dielectric properties than Ba(0.6)Sr(0.4)TiO(3)-La(Zn(0.5)Ti(0.5))O(3). 0.9Ba(0.6)Sr(0.4)TiO(3)-0.1La(Mg(0.5)Ti(0.5))O(3) has a dielectric constant epsilon = 338.2, Qf = 979 GHz and a tunability of was 3.7% at 100 kHz under 1.67 kV/mm. The Qf value of 0.5Ba(0.6)Sr(0.4)TiO(3)- 0.5La(Mg(0.5)Ti(0.5))O(3) reached 9367 GHz, but the tunable properties were lost.
Wang, Yang; Wang, Lu; Tian, Tian; Hu, Xiaoya; Yang, Chun; Xu, Qin
2012-05-21
In this study, an automated sequential injection lab-on-valve (SI-LOV) system was designed for the on-line matrix removal and preconcentration of quercetin. Octadecyl functionalized magnetic silica nanoparticles were prepared and packed into the microcolumn of the LOV as adsorbents. After being adsorbed through hydrophobic interaction, the analyte was eluted and subsequently introduced into the electrochemical flow cell by voltammetric quantification. The main parameters affecting the performance of solid-phase extraction, such as sample pH and flow rate, eluent solution and volume, accumulation potential and accumulation time were investigated in detail. Under the optimum experimental conditions, a linear calibration curve was obtained in the range of 1.0 × 10(-8) to 1 × 10(-5) mol L(-1) with R(2) = 0.9979. The limit of detection (LOD) and limit of quantitation (LOQ) were 1.3 × 10(-9) and 4.3 × 10(-9) mol L(-1), respectively. The relative standard deviation (RSD) for the determination of 1.0 × 10(-6) mol L(-1) quercetin was found to be 2.9% (n = 11) along with a sampling frequency of 40 h(-1). The applicability and reliability of the automated method described here had been applied to the determination of quercetin in human urine and red wine samples through recovery experiments, and the obtained results were in good agreement with those obtained by the HPLC method.
Effects of Shock-Breakout Pressure on Ejection of Micron-Scale Material from Shocked Tin Surfaces
NASA Astrophysics Data System (ADS)
Zellner, Michael; Hammerberg, James; Hixson, Robert; Morley, Kevin; Obst, Andrew; Olson, Russell; Payton, Jeremy; Rigg, Paulo; Buttler, William; Grover, Michael; Iverson, Adam; Macrum, Gregory; Stevens, Gerald; Turley, William; Veeser, Lynn; Routley, Nathan
2007-06-01
Los Alamos National Lab (LANL) is actively engaged in the development of a model to predict the formation of micron-scale fragments ejected (ejecta) from shocked metal surfaces. The LANL ejecta model considers that the amount of ejecta is mainly related to the material's phase on shock release at the free-surface. This effort investigates the relation between ejecta production and shock-breakout pressure for Sn shocked with high explosives to pressures near the solid-on-release/partial-liquid-on-release phase transition region. We found that the amount of ejecta produced for shock-breakout pressures that resulted in partial-liquid-on-release increased significantly compared to that which resulted in solid-on-release. Additionally, we found that the amount of ejecta remained relatively constant within the partial-liquid-on-release, regardless of shock-breakout pressure.
Pressure Effects on the Ejection of Material from Shocked Tin Surfaces
NASA Astrophysics Data System (ADS)
Zellner, M. B.; Grover, M.; Hammerberg, J. E.; Hixson, R. S.; Iverson, A. J.; Macrum, G. S.; Morley, K. B.; Obst, A. W.; Olson, R. T.; Payton, J. R.; Rigg, P. A.; Routley, N.; Stevens, G. D.; Turley, W. D.; Veeser, L.; Buttler, W. T.
2007-12-01
Los Alamos National Lab (LANL) is actively engaged in the development of a model to predict the formation of micron-scale fragments ejected (ejecta) from shocked metals that have surface defects. The LANL ejecta model considers that the amount of ejecta is mainly related to the material's phase on shock release at the free-surface. This effort investigates the relation between ejecta production and shock-breakout pressure for Sn shocked with high explosives to pressures near the solid-on-release/partial-liquid-on-release phase transition region. We found that the amount of ejecta produced for shock-breakout pressures that resulted in partial-liquid-on-release increased significantly compared to that which resulted in solid-on-release. Additionally, we found that the amount of ejecta remained relatively constant within the partial-liquid-on-release, regardless of shock-breakout pressure.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Keenan, Brett D., E-mail: bdkeenan@ku.edu; Medvedev, Mikhail V.
2015-11-15
Plasmas created by high-intensity lasers are often subject to the formation of kinetic-streaming instabilities, such as the Weibel instability, which lead to the spontaneous generation of high-amplitude, tangled magnetic fields. These fields typically exist on small spatial scales, i.e., “sub-Larmor scales.” Radiation from charged particles moving through small-scale electromagnetic (EM) turbulence has spectral characteristics distinct from both synchrotron and cyclotron radiation, and it carries valuable information on the statistical properties of the EM field structure and evolution. Consequently, this radiation from laser-produced plasmas may offer insight into the underlying electromagnetic turbulence. Here, we investigate the prospects for, and demonstrate themore » feasibility of, such direct radiative diagnostics for mildly relativistic, solid-density laser plasmas produced in lab experiments.« less
Idris, Ayman Salih Omer; Pandey, Ashok; Rao, S S; Sukumaran, Rajeev K
2017-10-01
The production of cellulase by Trichoderma reesei RUT C-30 under solid-state fermentation (SSF) on wheat bran and cellulose was optimized employing a two stage statistical design of experiments. Optimization of process parameters resulted in a 3.2-fold increase in CMCase production to 959.53IU/gDS. The process was evaluated at pilot scale in tray fermenters and yielded 457IU/gDS using the lab conditions and indicating possibility for further improvement. The cellulase could effectively hydrolyze alkali pretreated sorghum stover and addition of Aspergillus niger β-glucosidase improved the hydrolytic efficiency 174%, indicating the potential to use this blend for effective saccharification of sorghum stover biomass. The enzymatic hydrolysate of sorghum stover was fermented to ethanol with ∼80% efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.
Innovative single-shot diagnostics for electrons from laser wakefield acceleration at FLAME
NASA Astrophysics Data System (ADS)
Bisesto, F. G.; Anania, M. P.; Cianchi, A.; Chiadroni, E.; Curcio, A.; Ferrario, M.; Pompili, R.; Zigler, A.
2017-07-01
Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (> 100 GV/m), enabling acceleration of electrons to GeV energy in few centimeters. Here we present all the plasma related activities currently underway at SPARC_LAB exploiting the high power laser FLAME. In particular, we will give an overview of the single shot diagnostics employed: Electro Optic Sampling (EOS) for temporal measurement and Optical Transition Radiation (OTR) for an innovative one shot emittance measurements. In detail, the EOS technique has been employed to measure for the first time the longitudinal profile of electric field of fast electrons escaping from a solid target, driving the ions and protons acceleration, and to study the impact of using different target shapes. Moreover, a novel scheme for one shot emittance measurements based on OTR, developed and tested at SPARC_LAB LINAC, used in an experiment on electrons from laser wakefield acceleration still undergoing, will be shown.
King, J W; King, L J
1996-01-01
Because of the increase in use of the newer benzodiazepines, we explored the opportunity to develop a gas chromatographic-mass spectrometric (GC-MS) method that encompasses most of the widely prescribed benzodiazepines in use today. The benzodiazepines included in our study are nordiazepam, oxazepam, temazepam, lorazepam, alpha-hydroxyalprazolam, alpha-hydroxytriazolam, desalkylflurazepam, and 2-hydroxyethylflurazepam. Using 1.0 mL of urine as the matrix, we added the enzyme Glusulase and incubated the specimens for 2 h to obtain the free drugs. The hydrolyzed samples were then loaded onto a Toxi-Lab Spec VC MP3 column containing a 15-mg disc. On-disc derivatization was accomplished by adding N-methyl-N-(t-butyldimethylsilyl) trifluroacetamide (MTBSTFA) with 1% TBDMSCI to the disc. The derivatives were then placed in a GC vial and analyzed by GC-MS in the selected ion monitoring mode. These results were then compared to confirmed positives by the traditional acid hydrolysis GC-MS method.
Vermi composting--organic waste management and disposal.
Kumar, J Sudhir; Subbaiah, K Venkata; Rao, P V V Prasada
2012-01-01
Solid waste is an unwanted byproduct of modern civilization. Landfills are the most common means of solid waste disposal. But the increasing amount of solid waste is rapidly filling existing landfills, and new sites are difficult to establish. Alternatives to landfills include the use of source reduction, recycling, composting and incineration, as well as use of landfills. Incineration is most economical if it includes energy recovery from the waste. Energy can be recovered directly from waste by incineration or the waste can be processed to produce storable refuse derived fuel (RDF). Information on the composition of solid wastes is important in evaluating alternative equipment needs, systems, management programs and plans. Pulverization of municipal solid waste is done and the pulverized solid waste is dressed to form a bed and the bed is fed by earthworms which convert the bed into vermi compost. The obtained vermi compost is sent to Ministry of Environment & Forests (MoEF) recognized lab for estimating the major nutrients, i.e. Potassium (K), Phosphorous (P), Nitrogen (N) and Micro-nutrient values. It is estimated that 59 - 65 tons of wet waste can be collected in a town per day and if this wet waste is converted to quality compost, around 12.30 tons of vermi compost can be generated. If a Municipal Corporation manages this wet waste an income of over (see text symbol) for 0.8 9 crore per anum can be earned which is a considerable amount for providing of better services to public.
A persistent-mode 0.5 T solid-nitrogen-cooled MgB2 magnet for MRI.
Ling, Jiayin; Voccio, John P; Hahn, Seungyong; Qu, Timing; Bascuñán, Juan; Iwasa, Yukikazu
2017-02-01
This paper presents construction details and test results of a persistent-mode 0.5-T MgB 2 magnet developed at the Francis Bitter Magnet Lab, MIT. The magnet, of 276-mm inner diameter and 290-mm outer diameter, consisted of a stack of 8 solenoidal coils with a total height of 460 mm. Each coil was wound with monofilament MgB 2 wire, equipped with a persistent-current switch and terminated with a superconducting joint, forming an individual superconducting loop. Resistive solder joints connected the 8 coils in series. The magnet, after being integrated into a testing system, immersed in solid nitrogen, was operated in a temperature range of 10-13 K. A two-stage cryocooler was deployed to cool a radiation shield and the cold mass that included mainly ~60 kg of solid nitrogen and the magnet. The solid nitrogen was capable of providing a uniform and stable cryogenic environment to the magnet. The magnet sustained a 0.47-T magnetic field at its center persistently in a range of 10-13 K. The current in each coil was inversely calculated from the measured field profile to determine the performance of each coil in persistent-mode operation. Persistent-current switches were successfully operated in solid nitrogen for ramping the magnet. They were also designed to absorb magnetic energy in a protection mechanism; its effectiveness was evaluated in an induced quench.
Fauvel, Blandine; Ogorzaly, Leslie; Cauchie, Henry-Michel; Gantzer, Christophe
2017-01-01
The association of viruses with settling particles is certainly a major process controlling the spread of viral pollution in surface water and sediment. To better understand the viral distribution in a river system, the behavior of F-specific RNA bacteriophages (FRNAPHs) was investigated in relationship with the suspended solids and sediment. The partitioning of phage particles (free or associated with solids) in surface water and the attachment capabilities of eight distinct strains of phages to sediment were studied in lab experiments. In situ observations were also performed with the genotyping of 166 individual plaques of FRNAPHs isolated from surface water and sediment. The results reported here demonstrate a variation of the status of infectious phages as a function of the hydro-climatological conditions. Phage-solid association seems to mainly occur during the peak of rainfall-runoff events but also to a certain extent during the recession phase compared to low flow conditions. The transfer of phages from the water column to sediment may occur at this time. Furthermore, the ability of FRNAPHs to interact with sediment was established for six strains out of eight, belonging to genogroups II, III and IV. A similar dynamic was observed for strains within a same genogroup despite different intensity of attachment and inactivation rates for strains of genogroups III and IV. The latter results match the in situ observations in the water and sediment compartments of the studied area. Infectious FRNAPH genogroup II was more abundant in sediment than in surface water. Its capability to sorb to sediment and its higher persistence in the environment compared to genogroups III and IV were the two main explanations. Together, lab and in situ experiments produce an overall vision of the mechanisms governing FRNAPH distribution among the water column and riverbed sediment. Copyright © 2016 Office national des forêts. Published by Elsevier B.V. All rights reserved.
Baharfar, Mahroo; Yamini, Yadollah; Seidi, Shahram; Arain, Muhammad Balal
2018-05-30
A new design of electromembrane extraction (EME) as a lab on-a-chip device was proposed for the extraction and determination of phenazopyridine as the model analyte. The extraction procedure was accomplished by coupling of EME and the packing of a sorbent. The analyte was extracted under the applied electrical field across a membrane sheet impregnated by nitrophenyl octylether (NPOE) into an acceptor phase. It was followed by the absorption of the analyte on strong cation exchanger as a sorbent. The designed chip contained separate spiral channels for donor and acceptor phases featuring embedded platinum electrodes to enhance extraction efficiency. The selected donor and acceptor phases were 0 mM HCl and 100 mM HCl, respectively. The on-chip electromembrane extraction was carried out under the voltage level of 70 V for 50 min. The analysis was carried out by two modes of a simple Red-Green-Blue (RGB) image analysis tool and a conventional HPLC-UV system. After the absorption of the analyte on the solid phase, its color changed and a digital picture of the sorbent was taken for the RGB analysis. The effective parameters on the performance of the chip device, comprising the EME and solid phase microextraction steps, were distinguished and optimized. The accumulation of the analyte on the solid phase showed excellent sensitivity and a limit of detection (LOD) lower than 1.0 μg L-1 achieved by an image analysis using a smartphone. This device also offered acceptable intra- and inter-assay RSD% (<10%). The calibration curves were linear within the range of 10-1000 μg L-1 and 30-1000 μg L-1 (r2 > 0.9969) for HPLC-UV and RGB analysis, respectively. To investigate the applicability of the method in complicated matrices, urine samples of patients being treated with phenazopyridine were analyzed.
The effectiveness of computer-generated 3D animations in inquiry chemistry laboratory
NASA Astrophysics Data System (ADS)
Theall, Rachel Morgan
It has been shown that students need a molecular-level understanding of substances in order to comprehend chemistry. For solid structures, atomic-level understanding requires students to learn additional and different concepts than for other states of matter. To aid understanding, animations were created to model unit cell structures and depict the properties of unit cells. In order to determine if these animations are helpful to students, they were tested during a laboratory exercise in which students had previously been using model kits and images from textbooks to learn about solid structures. Students evaluated in this study were from two lecture sections of general chemistry, one that routinely used animations during lecture and one that used a more traditional lecture format that did not include animations or models. Twelve laboratory sections of these lectures, taught by six different instructors each teaching two sections, were chosen for participation. One section for each instructor was given the animations as an optional tool for completing the laboratory assignment, which consisted of questions about unit cells and crystal structures. The results of the study indicate that students who looked at the animations performed significantly better on the assignment. For the control group, students who routinely viewed multiple representations of chemistry in lecture performed significantly better on the lab assignment than students in the lecture section where chemistry concepts were only presented on the chalkboard and overhead projector. Students in the traditional lecture section also had significantly less appreciation for the model kits used in the laboratory than students in the other lecture section. Observations of students in the lab combined with statistical results led to the revision of the solid structures investigation. Additional animations were created and inserted into the module that covered areas where students indicated more help was needed. Movies of "real life" chemistry were also incorporated into the module to help students relate the investigation to prior knowledge.
Santymire, R M; Armstrong, D M
2010-01-01
Hormonal analysis provides information about wildlife populations, but is difficult to conduct in the field. Our goal was to develop a rapid and effective field method for fecal steroid analysis by comparing: (1) three extraction methods (laboratory (LAB), homogenize (HO) and handshake (HS)) and (2) two storage methods (solid-phase extraction (SPE) tubes vs. plastic tubes (PT)). Samples (n=23) from captive African wild dogs (Lycaon pictus) were thoroughly mixed, three aliquots of each were weighed ( approximately 0.5 g) and 5 ml of 90% ethanol was added. For LAB, samples were agitated (mixer setting 60; 30 min), centrifuged (1,500 rpm; 20 min) and poured into glass tubes. Or aliquots were HO (1 min) or HS (1 min) and poured through filter paper into glass tubes. Samples were split, analyzed for corticosterone (C) and testosterone (T) metabolites using enzyme immunoassays or stored in SPE or PT. Samples were stored (room temperature) for 30, 60 or 180 days, reconstituted in buffer and analyzed. Mean C and T recoveries of HO were greater (P=0.03) than HS compared with LAB, which was similar to HO (P>0.05). After 30 days <21% of C and T was recovered from SPE, but approximately 100% of each was recovered from HO-PT and HS-PT. Similarly, after 60 and 180 days, approximately 100% of C and T was recovered from HO-PT and HS-PT. Results demonstrated that, for C and T, HO was more comparable (P<0.001) to LAB than HS and PT storage was more efficient than SPE (P<0.001). (c) 2009 Wiley-Liss, Inc.
A Lab-on-Chip Design for Miniature Autonomous Bio-Chemoprospecting Planetary Rovers
NASA Astrophysics Data System (ADS)
Santoli, S.
The performance of the so-called ` Lab-on-Chip ' devices, featuring micrometre size components and employed at present for carrying out in a very fast and economic way the extremely high number of sequence determinations required in genomic analyses, can be largely improved as to further size reduction, decrease of power consumption and reaction efficiency through development of nanofluidics and of nano-to-micro inte- grated systems. As is shown, such new technologies would lead to robotic, fully autonomous, microwatt consumption and complete ` laboratory on a chip ' units for accurate, fast and cost-effective astrobiological and planetary exploration missions. The theory and the manufacturing technologies for the ` active chip ' of a miniature bio/chemoprospecting planetary rover working on micro- and nanofluidics are investigated. The chip would include micro- and nanoreactors, integrated MEMS (MicroElectroMechanical System) components, nanoelectronics and an intracavity nanolaser for highly accurate and fast chemical analysis as an application of such recently introduced solid state devices. Nano-reactors would be able to strongly speed up reaction kinetics as a result of increased frequency of reactive collisions. The reaction dynamics may also be altered with respect to standard macroscopic reactors. A built-in miniature telemetering unit would connect a network of other similar rovers and a central, ground-based or orbiting control unit for data collection and transmission to an Earth-based unit through a powerful antenna. The development of the ` Lab-on-Chip ' concept for space applications would affect the economy of space exploration missions, as the rover's ` Lab-on-Chip ' development would link space missions with the ever growing terrestrial market and business concerning such devices, largely employed in modern genomics and bioinformatics, so that it would allow the recoupment of space mission costs.
Hunaefi, Dase; Akumo, Divine N.; Riedel, Heidi; Smetanska, Iryna
2012-01-01
High rosmarinic acid (RA) productivity has been achieved by applying jasmonic acid and yeast extract elicitors to the in vitro sprout culture of Orthosiphon aritatus (IOSC). The highest RA accumulation from three solvents was detected in IOSC after treatment with yeast extract (5 g/L). HPLC analysis clearly confirmed a drastic increase in RA subjected to yeast extract elicitation. Therefore, this yeast extract elicited IOSC was chosen for a lactic acid bacteria (LAB) fermentation study as a model system. This selected IOSC was subjected to different types of LAB fermentations (Lactobacillus plantarum ATCC 8014 and Lactobacillus acidophilus NCFM) for different periods of time 24, 48 and 72 h. The LAB fermentations consisted of solid state fermentations (SSF) and liquid state fermentations (LSF) in a Digital Control Unit (DCU) fermenter system. The aim was to determine the effect of fermentation on the antioxidant properties of the plant extract. Results indicated that all types of LAB fermentation decreased the level of RA and total phenolics, however, a slight increase in total flavonoids and flavonols was observed in SSF samples. HPLC results confirmed that the longer the fermentation, the greater the reduction in RA content. The highest reduction was obtained in the sample of LSF inoculated with L. plantarum for a period of 72 h. The temperature of fermentation (37 °C) was predicted as contributing to the declining level in RA content. The loss in RA was concomitant with a loss of total antioxidant activity (1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity, Trolox Equivalent Antioxidant Capacity (TEAC), and Superoxide Dismutase (SOD)-like activity). These results indicate that RA is the major contributor to the antioxidant activity of this plant. PMID:26787613
Cano, R; Nielfa, A; Fdz-Polanco, M
2014-09-01
An economic assessment of thermal hydrolysis as a pretreatment to anaerobic digestion has been achieved to evaluate its implementation in full-scale plants. Six different solid wastes have been studied, among them municipal solid waste (MSW). Thermal hydrolysis has been tested with batch lab-scale tests, from which an energy and economic assessment of three scenarios is performed: with and without energy integration (recovering heat to produce steam in a cogeneration plant), finally including the digestate management costs. Thermal hydrolysis has lead to an increase of the methane productions (up to 50%) and kinetics parameters (even double). The study has determined that a proper energy integration design could lead to important economic savings (5 €/t) and thermal hydrolysis can enhance up to 40% the incomes of the digestion plant, even doubling them when digestate management costs are considered. In a full-scale MSW treatment plant (30,000 t/year), thermal hydrolysis would provide almost 0.5 M€/year net benefits. Copyright © 2014 Elsevier Ltd. All rights reserved.
Drechsel, Lisa; Schulz, Martin; von Stetten, Felix; Moldovan, Carmen; Zengerle, Roland; Paust, Nils
2015-02-07
Lab-on-a-chip devices hold promise for automation of complex workflows from sample to answer with minimal consumption of reagents in portable devices. However, complex, inhomogeneous samples as they occur in environmental or food analysis may block microchannels and thus often cause malfunction of the system. Here we present the novel AutoDip platform which is based on the movement of a solid phase through the reagents and sample instead of transporting a sequence of reagents through a fixed solid phase. A ball-pen mechanism operated by an external actuator automates unit operations such as incubation and washing by consecutively dipping the solid phase into the corresponding liquids. The platform is applied to electrochemical detection of organophosphorus pesticides in real food samples using an acetylcholinesterase (AChE) biosensor. Minimal sample preparation and an integrated reagent pre-storage module hold promise for easy handling of the assay. Detection of the pesticide chlorpyrifos-oxon (CPO) spiked into apple samples at concentrations of 10(-7) M has been demonstrated. This concentration is below the maximum residue level for chlorpyrifos in apples defined by the European Commission.
NASA Technical Reports Server (NTRS)
Stocker, H. L.; Cox, D. M.; Holle, G. F.
1977-01-01
Labyrinth air seal static and dynamic performance was evaluated using solid, abradable, and honeycomb lands with standard and advanced seal designs. The effects on leakage of land surface roughness, abradable land porosity, rub grooves in abradable lands, and honeycomb land cell size and depth were studied using a standard labyrinth seal. The effects of rotation on the optimum seal knife pitch were also investigated. Selected geometric and aerodynamic parameters for an advanced seal design were evaluated to derive an optimized performance configuration. The rotational energy requirements were also measured to determine the inherent friction and pumping energy absorbed by the various seal knife and land configurations tested in order to properly assess the net seal system performance level. Results indicate that: (1) seal leakage can be significantly affected with honeycomb or abradable lands; (2) rotational energy absorption does not vary significantly with the use of a solid-smooth, an abradable, or a honeycomb land; and (3) optimization of an advanced lab seal design produced a configuration that had leakage 25% below a conventional stepped seal.
Chen, Sisi; Li, Ning; Dong, Bin; Zhao, Wentao; Dai, Lingling; Dai, Xiaohu
2018-01-15
Two lab-scale high solid anaerobic digesters fed with untreated sludge (R1) and thermally hydrolyzed sludge (R2) were operated to investigate the influence of thermal hydrolysis pretreatment (THP) on the degradation of individual macromolecular organic components (MOCs), as well as the functional and metabolic responses of microbes during anaerobic digestion (AD). The degradation of MOCs was improved by THP at different rates, in which improved degradation of proteins (by 49.0%) and hemicelluloses (by 25.0%) were the main factors contributing to the increase in volatile solids (VS) reduction. However, no enhancement of final degradation extent of MOCs was observed. With a more densified microbial population, R2 was also enriched in genes involved in amino acid and carbohydrate metabolism, reflected in the enhanced degradation of proteins and carbohydrates. After THP, the methanogenic pathway shifted from strict acetoclastic methanogenesis to acetoclastic/hydrogenotrophic methanogenesis, consistent with the enhanced methane production and the increase of methane content. Copyright © 2017 Elsevier B.V. All rights reserved.
Some considerations on the current debate about typing resolution in solid organ transplantation.
Vogiatzi, Paraskevi
2016-01-01
The shortage of suitable organs and achieved tolerance are uncontested main concerns in transplantation. Long waiting lists for deceased donors and limited numbers of living donors are the current scenarios. Kidney grafts from living donors have better overall survival compared to cadaveric and require less aggressive immunosuppressive regimens. The human leukocyte antigen (HLA) labs have the key role to test the recipient and donors compatibility based on typing and antibody profile. The current standard molecular procedure in solid organ transplantation is low-resolution typing, at the antigen level. In this commentary, the merits of high versus low degree of typing resolution in solid organ transplantation are discussed. Critical questions and reasons to bring high-resolution typing as a routine test in health system are considered. Specifically, with the introduction of the next-generation sequencing (NGS) in HLA, the pros and cons in living donation and benefits after deceased donation are critically evaluated. NGS has the potential to improve the transplant rates and the overall graft survival. Alternative strategies to increase in demanding the number of transplants are briefly highlighted.
The Tensor and the Scalar Charges of the Nucleon from Hadron Phenomenology
NASA Astrophysics Data System (ADS)
Courtoy, A.
2018-01-01
We discuss the impact of the determination of the nucleon tensor charge on searches for physics Beyond the Standard Model. We also comment on the future extraction of the subleading-twist PDF e(x) from Jefferson Lab soon-to-be-released Beam Spin Asymmetry data as well as from the expected data of CLAS12 and SoLID, as the latter is related to the scalar charge. These analyses are possible through the phenomenology of Dihadron Fragmentation Functions related processes, which we report on here as well.
2001-01-17
The U.S. Lab Destiny (left) moves away from Atlantis’ payload bay doors (right) into the Payload Changeout Room. Destiny will remain in the PCR while Atlantis rolls back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster’s system tunnel. An extensive evaluation of NASA’s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis
2001-01-17
Workers in the Payload Changeout Room check the U.S. Lab Destiny as its moves from Atlantis’ payload bay into the PCR. Destiny will remain in the PCR while Atlantis rolls back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster’s system tunnel. An extensive evaluation of NASA’s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis
2001-01-17
Workers in the Payload Changeout Room check the U.S. Lab Destiny as its moves from Atlantis’ payload bay into the PCR. Destiny will remain in the PCR while Atlantis rolls back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster’s system tunnel. An extensive evaluation of NASA’s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis
2001-01-17
The U.S. Lab Destiny is ready to be moved from Atlantis’ payload bay into the Payload Changeout Room. After the move, Atlantis will roll back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster’s system tunnel. An extensive evaluation of NASA’s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis
Tools for Implementing Science Practice in a Large Introductory Class
NASA Astrophysics Data System (ADS)
Prothero, W. A.
2008-12-01
Scientists must have in-depth background knowledge of their subject area and know where current knowledge can be advanced. They perform experiments that gather data to test new or existing theories, present their findings at meetings, publish their results, critically review the results of others, and respond to the reviews of their own work. In the context of a course, these activities correspond to learning the background material by listening to lectures or reading a text, formulating a problem, exploring data using student friendly data access and plotting software, giving brief talks to classmates in a small class or lab setting, writing a science paper or lab report, reviewing the writing of their peers, and receiving feedback (and grades) from their instructors and/or peers. These activities can be supported using course management software and online resources. The "LearningWithData" software system allows solid Earth (focused on plate tectonics) data exploration and plotting. Ocean data access, display, and plotting are also supported. Background material is delivered using animations and slide show type displays. Students are accountable for their learning through included homework assignments. Lab and small group activities provide support for data exploration and interpretation. Writing is most efficiently implemented using the "Calibrated Peer Review" method. This methodology is available at http://cpr.molsci.ucla.edu/. These methods have been successfully implemented in a large oceanography class at UCSB.
Insulation Reformulation Development
NASA Technical Reports Server (NTRS)
Chapman, Cynthia; Bray, Mark
2015-01-01
The current Space Launch System (SLS) internal solid rocket motor insulation, polybenzimidazole acrylonitrile butadiene rubber (PBI-NBR), is a new insulation that replaced asbestos-based insulations found in Space Shuttle heritage solid rocket boosters. PBI-NBR has some outstanding characteristics such as an excellent thermal erosion resistance, low thermal conductivity, and low density. PBI-NBR also has some significant challenges associated with its use: Air entrainment/entrapment during manufacture and lay-up/cure and low mechanical properties such as tensile strength, modulus, and fracture toughness. This technology development attempted to overcome these challenges by testing various reformulated versions of booster insulation. The results suggest the SLS program should continue to investigate material alternatives for potential block upgrades or use an entirely new, more advanced booster. The experimental design was composed of a logic path that performs iterative formulation and testing in order to maximize the effort. A lab mixing baseline was developed and documented for the Rubber Laboratory in Bldg. 4602/Room 1178.
Graphene Based Ultra-Capacitors for Safer, More Efficient Energy Storage
NASA Technical Reports Server (NTRS)
Roberson, Luke B.; Mackey, Paul J.; Zide, Carson J.
2016-01-01
Current power storage methods must be continuously improved in order to keep up with the increasingly competitive electronics industry. This technological advancement is also essential for the continuation of deep space exploration. Today's energy storage industry relies heavily on the use of dangerous and corrosive chemicals such as lithium and phosphoric acid. These chemicals can prove hazardous to the user if the device is ruptured. Similarly they can damage the environment if they are disposed of improperly. A safer, more efficient alternative is needed across a wide range of NASA missions. One solution would a solid-state carbon based energy storage device. Carbon is a safer, less environmentally hazardous alternative to current energy storage materials. Using the amorphous carbon nanostructure, graphene, this idea of a safer portable energy is possible. Graphene was electrochemically produced in the lab and several coin cell devices were built this summer to create a working prototype of a solid-state graphene battery.
NASA Technical Reports Server (NTRS)
Martin, Heath T.
2015-01-01
Due to the severity of the internal solid rocket motor (SRM) environment, very few direct measurements of that environment exist; therefore, the appearance of such data provides a unique opportunity to assess current thermal/fluid modeling capabilities. As part of a previous study of SRM internal insulation performance, the internal thermal environment of a laboratory-scale SRM featuring aluminized propellant was characterized with two types of custom heat-flux calorimeters: one that measured the total heat flux to a graphite slab within the SRM chamber and another that measured the thermal radiation flux. Therefore, in the current study, a thermal/fluid model of this lab-scale SRM was constructed using ANSYS Fluent to predict not only the flow field structure within the SRM and the convective heat transfer to the interior walls, but also the resulting dispersion of alumina droplets and the radiative heat transfer to the interior walls. The dispersion of alumina droplets within the SRM chamber was determined by employing the Lagrangian discrete phase model that was fully coupled to the Eulerian gas-phase flow. The P1-approximation was engaged to model the radiative heat transfer through the SRM chamber where the radiative contributions of the gas phase were ignored and the aggregate radiative properties of the alumina dispersion were computed from the radiative properties of its individual constituent droplets, which were sourced from literature. The convective and radiative heat fluxes computed from the thermal/fluid model were then compared with those measured in the lab-scale SRM test firings and the modeling approach evaluated.
A batch adsorption study on bentonite clay Pertinence to transport modeling?
NASA Astrophysics Data System (ADS)
BOURG, I.; BOURG, A. C.; SPOSITO, G.
2001-12-01
Bentonite clay is often used as a component of engineered barriers for the isolation of high-level toxic wastes. This swelling clay is used for its physical (impermeability, self-healing) but also for its chemical properties, mostly a high cation exchange capacity (CEC). The adsorbed cations being temporarily immobilized, this should slow down the release of cations from the waste to the surrounding environment. In order to assess the performance of the engineered barrier, the partitioning of solutes between the liquid and solid phases needs to be quantified for use in transport models. The usual method for characterizing the adsorption is through batch adsorption experiments on dispersed suspensions of the solid, yielding an adsorption isotherm (adsorbed concentration vs. dissolved concentration). This isotherm however should be a function of various environmental variables (e.g., pH, ionic strength, concentrations of various ligands and competing adsorbents), so that extrapolation of lab data to performance assessment in the field is problematic. We present results from a study of the adsorption of cesium, strontium, cadmium and lead on dispersed suspensions of the standard BX-80 bentonite. Through a wide range of experimental parameters (pH, ionic strength, reaction time, reactor open or closed to the atmosphere, study of a range of cations of differing properties), we seek a mechanistic interpretation of the results instead of an empirical determination of adsorption parameters. Depending on the mechanisms that control the adsorption in different experimental ranges, we discuss the degree to which the partitioning coefficient (Kd) obtained in the lab can be extrapolated to a transport model through compacted bentonite in a natural environment.
Komilis, Dimitrios; Katsafaros, Nikolaos; Vassilopoulos, Panagiotis
2011-08-01
The accurate calculation of the unit generation rates and composition of medical waste generated from medical facilities is necessary in order to design medical waste treatment systems. In this work, the unit medical waste generation rates of 95 public and private medical facilities in the Attica region were calculated based on daily weight records from a central medical waste incineration facility. The calculated medical waste generation rates (in kg bed(-1) day( -1)) varied widely with average values at 0.27 ± 113% and 0.24 ± 121%, for public and private medical facilities, respectively. The hazardous medical waste generation was measured, at the source, in the 40 bed hospital of the island of Ikaria for a period of 42 days during a 6 month period. The average hazardous medical waste generation rate was 1.204 kg occupied bed(-1) day(-1) or 0.33 kg (official) bed( -1) day(-1). From the above amounts, 54% resulted from the patients' room (solid and liquid wastes combined), 24% from the emergency department (solid waste), 17% from the clinical pathology lab and 6% from the X-ray lab. In average, 17% of the total hazardous medical waste was solely infectious. Conclusively, no correlation among the number of beds and the unit medical waste generation rate could be established. Each hospital should be studied separately, since medical waste generation and composition depends on the number and type of departments/laboratories at each hospital, number of external patients and number of occupied beds.
The contribution of weathering of the main Alpine rivers on the global carbon cycle
NASA Astrophysics Data System (ADS)
Donnini, Marco; Probst, Jean-Luc; Probst, Anne; Frondini, Francesco; Marchesini, Ivan; Guzzetti, Fausto
2013-04-01
On geological time-scales the carbon fluxes from the solid Earth to the atmosphere mainly result from volcanism and metamorphic-decarbonation processes, whereas the carbon fluxes from atmosphere to solid Earth mainly depend on weathering of silicates and carbonates, biogenic precipitation and removal of CaCO3 in the oceans and volcanic gases - seawater interactions. Quantifying each contribution is critical. In this work, we estimate the atmospheric CO2 uptake by weathering in the Alps, using results of the study of the dissolved loads transported by 33 main Alpine rivers. The chemical composition of river water in unpolluted areas is a good indicator of surface weathering processes (Garrels and Mackenzie, 1971; Drever, 1982; Meybeck, 1984; Tardy, 1986; Berner and Berner, 1987; Probst et al., 1994). The dissolved load of streams originates from atmospheric input, pollution, evaporite dissolution, and weathering of carbonate and silicate rocks, and the application of mass balance calculations allows quantification of the different contributions. In this work, we applied the MEGA (Major Element Geochemical Approach) geochemical code (Amiotte Suchet, 1995; Amiotte Suchet and Probst, 1996) to the chemical compositions of the selected rivers in order to quantify the atmospheric CO2 consumed by weathering in Alpine region. The drainage basins of the main Alpine rivers were sampled near the basin outlets during dry and flood seasons. The application of the MEGA geochemical consisted in several steps. First, we subtracted the rain contribution in river waters knowing the X/Cl (X = Na, K, Mg, Ca) ratios of the rain. Next, we considered that all (Na+K) came from silicate weathering. The average molar ratio Rsil = (Na+K)/(Ca+Mg) for rivers draining silicate terrains was estimated from unpolluted French stream waters draining small monolithological basins (Meybeck, 1986; 1987). For the purpose, we prepared a simplified geo-lithological map of Alps according to the lithological classification of Meybeck (1986, 1987). Then for each basin we computed Rsil weighted average considering the surface and the mean precipitation for the surface area of each lithology. Lastly, we estimated the (Ca+Mg) originating from carbonate weathering as the remaining cations after silicate correction. Depending on time-scales of the phenomena (shorter than about 1 million year i.e., correlated to the short term carbon cycle, or longer than about 1 million years i.e., correlated to the long-term carbon cycle), we considered different equations for the quantification of the atmospheric CO2 consumed by weathering (Huh, 2010). The results show the net predominance of carbonate weathering on fixing atmospheric CO2 and that, considering the long-term carbon cycle, the amount of atmospheric CO2 uptake by weathering is about one order of magnitude lower than considering the short-term carbon cycle. Moreover, considering the short-term carbon cycle, the mean CO2 consumed by Alpine basins is of the same order of magnitude of the mean CO2 consumed by weathering by the 60 largest rivers of the world estimated by Gaillardet et al. (1999). References Amiotte-Suchet, P. "Cycle Du Carbone, Érosion Chimique Des Continents Et Transfert Vers Les Océans." Sci. Géol. Mém. Strasbourg 97 (1995): 156. Amiotte-Suchet, P., and J.-L. Probst. "Origins of dissolved inorganic carbon in the Garonne river waters: seasonal and interannual variations." Sci. Géologiques Bull. Strasbourg 49, no. 1-4 (1996): 101-126. Berner, E.K., and R.A. Berner. The Global Water Cycle. Geochemistry and Environment. Prentice Halle. Engelwood Cliffs, NJ, 1987. Drever, J.L. The Geochemistry of Natural Waters. Prentice Hall, 1982. Gaillardet, J., B. Dupré, P. Louvat, and C.J. Allègre. "Global Silicate Weathering and CO2 Consumption Rates Deduced from the Chemistry of Large Rivers." Chemical Geology 159 (1999): 3-30. Garrels, R.M., and F.T. Mackenzie. Evolution of Sedimentary Rocks. New York: W.W. Nortonand, 1971. Huh, Y. "Estimation of Atmospheric CO2 Uptake by Silicate Weathering in the Himalayas and the Tibetan Plateau: a Review of Existing Fluvial Geochemical Data." In Monsoon Evolution and Tectonics-Climate Linkage in Asia, 129-151. Geological Society of London, Special Publications. 342. London, 2010. Meybeck, M. "Composition Chimique Naturelle Des Ruisseaux Non Pollués En France." Bullettin De La Société Géologique 39 (1986): 3-77. Meybeck, M. "Global Chemical Weathering of Surficial Rocks Estimated from River Dissolved Load." Am. J. Sci 287 (1987): 401-428. Probst J.L., Mortatti J. And Tardy Y. 1994- Carbon river fluxes and global weathering CO2 consumption in the Congo and Amazon river basins. Applied Geochemistry, 9, p 1-13 Tardy, Y. Le Cycle De l'Eau. Climats, Paléoclimates Et Géochimie Globale. Masson. Paris, 1986.
Peeters, Bart; Dewil, Raf; Vernimmen, Luc; Van den Bogaert, Benno; Smets, Ilse Y
2013-07-01
This paper presents a new application of polyaluminiumchloride (PACl) as a conditioner for waste activated sludge prior its dewatering and drying. It is demonstrated at lab scale with a shear test-based protocol that a dose ranging from 50 to 150 g PACl/kg MLSS (mixed liquor suspended solids) mitigates the stickiness of partially dried sludge with a dry solids content between 25 and 60 %DS (dry solids). E.g., at a solids dryness of 46% DS the shear stress required to have the pre-consolidated sludge slip over a steel surface is reduced with 35%. The salient feature of PACl is further supported by torque data from a full scale decanter centrifuge used to dewater waste sludge. The maximal torque developed by the screw conveyor inside the decanter centrifuge is substantially reduced with 20% in the case the sludge feed is conditioned with PACl. The beneficial effect of waste sludge conditioning with PACl is proposed to be the result of the bound water associated with the aluminium polymers in PACl solutions which act as a type of lubrication for the intrinsically sticky sludge solids during the course of drying. It can be anticipated that PACl addition to waste sludge will become a technically feasible and very effective method to avoid worldwide fouling problems in direct sludge dryers, and to reduce torque issues in indirect sludge dryers as well as in sludge decanter centrifuges. Copyright © 2013 Elsevier Ltd. All rights reserved.
A persistent-mode 0.5 T solid-nitrogen-cooled MgB2 magnet for MRI
Ling, Jiayin; Voccio, John P.; Hahn, Seungyong; Qu, Timing; Bascuñán, Juan; Iwasa, Yukikazu
2017-01-01
This paper presents construction details and test results of a persistent-mode 0.5-T MgB2 magnet developed at the Francis Bitter Magnet Lab, MIT. The magnet, of 276-mm inner diameter and 290-mm outer diameter, consisted of a stack of 8 solenoidal coils with a total height of 460 mm. Each coil was wound with monofilament MgB2 wire, equipped with a persistent-current switch and terminated with a superconducting joint, forming an individual superconducting loop. Resistive solder joints connected the 8 coils in series. The magnet, after being integrated into a testing system, immersed in solid nitrogen, was operated in a temperature range of 10–13 K. A two-stage cryocooler was deployed to cool a radiation shield and the cold mass that included mainly ~60 kg of solid nitrogen and the magnet. The solid nitrogen was capable of providing a uniform and stable cryogenic environment to the magnet. The magnet sustained a 0.47-T magnetic field at its center persistently in a range of 10–13 K. The current in each coil was inversely calculated from the measured field profile to determine the performance of each coil in persistent-mode operation. Persistent-current switches were successfully operated in solid nitrogen for ramping the magnet. They were also designed to absorb magnetic energy in a protection mechanism; its effectiveness was evaluated in an induced quench. PMID:28966476
NASA Astrophysics Data System (ADS)
Kawamuro, Taiki; Schirmer, Mischa; Turner, James E. H.; Davies, Rebecca L.; Ichikawa, Kohei
2017-10-01
We have shown that Lyα blobs (LABs) may still exist even at z˜ 0.3, about seven billion years later than most other LABs known (Shirmer et al.). Their luminous Lyα and [O III] emitters at z˜ 0.3 offer new insights into the ionization mechanism. This paper focuses on the two X-ray brightest LABs at z˜ 0.3, SDSS J0113+0106 (J0113) and SDSS J1155-0147 (J1155), comparable in size and luminosity to “B1,” one of the best-studied LABs at z≳ 2. Our NuSTAR hard X-ray (3-30 keV) observations reveal powerful active galactic nuclei (AGN) with {L}2{--10{keV}}=(0.5{--}3)× {10}44 erg s-1. J0113 also faded by a factor of ˜5 between 2014 and 2016, emphasizing that variable AGN may cause apparent ionization deficits in LABs. Joint spectral analyses including Chandra data constrain column densities of {N}{{H}}={5.1}-3.3+3.1× {10}23 cm-2 (J0113) and {N}{{H}}={6.0}-1.1+1.4× {10}22 cm-2 (J1155). J0113 is likely buried in a torus with a narrow ionization cone, but ionizing radiation is also leaking in other directions, as revealed by our Gemini/GMOS 3D spectroscopy. The latter shows a bipolar outflow over 10 kpc, with a peculiar velocity profile that is best explained by AGN flickering. X-ray analysis of J1155 reveals a weakly absorbed AGN that may ionize over a wide solid angle, consistent with our 3D spectra. Extinction-corrected [O III] log-luminosities are high, ˜43.6. The velocity dispersions are low, ˜100-150 km s-1, even at the AGN positions. We argue that this is a combination of high extinction hiding the turbulent gas and previous outflows that have cleared the escape paths for their successors.
Di-hadron production at Jefferson Lab
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anefalos Pereira, Sergio; et. al.,
Semi-inclusive deep inelastic scattering (SIDIS) has been used extensively in recent years as an important testing ground for QCD. Studies so far have concentrated on better determination of parton distribution functions, distinguishing between the quark and antiquark contributions, and understanding the fragmentation of quarks into hadrons. Hadron pair (di-hadron) SIDIS provides information on the nucleon structure and hadronization dynamics that complement single hadron SIDIS. Di-hadrons allow the study of low- and high-twist distribution functions and Dihadron Fragmentation Functions (DiFF). Together with the twist-2 PDFs ( f1, g1, h1), the Higher Twist (HT) e and hL functions are very interesting becausemore » they offer insights into the physics of the largely unexplored quark-gluon correlations, which provide access into the dynamics inside hadrons. The CLAS spectrometer, installed in Hall-B at Jefferson Lab, has collected data using the CEBAF 6 GeV longitudinally polarized electron beam on longitudinally polarized solid NH3 targets. Preliminary results on di-hadron beam-, target- and double-spin asymmetries will be presented.« less
Airborne microorganisms from waste containers.
Jedlicka, Sabrina S; Stravitz, David M; Lyman, Charles E
2012-01-01
In physician's offices and biomedical labs, biological waste is handled every day. This waste is disposed of in waste containers designed for holding red autoclave bags. The containers used in these environments are closed hands-free containers, often with a step pedal. While these containers protect the user from surface-borne microorganisms, the containers may allow airborne microorganisms to escape via the open/close mechanism because of the air current produced upon open/close cycles. In this study, the air current was shown to be sufficient to allow airborne escape of microorganisms held in the container, including Aspergillus niger. However, bacterial cultures, such as Escherichia coli and Lactococcus lactis did not escape. This may be due to the choice of bacterial cultures and the absence of solid waste, such as dust or other particulate matter in the waste containers, that such strains of bacteria could travel on during aerosolization. We compared these results to those obtained using a re-designed receptacle, which mimimizes air currents, and detected no escaping microorganisms. This study highlights one potential source of airborne contamination in labs, hospitals, and other environments that dispose of biological waste.
Experimental investigation of fuel regression rate in a HTPB based lab-scale hybrid rocket motor
NASA Astrophysics Data System (ADS)
Li, Xintian; Tian, Hui; Yu, Nanjia; Cai, Guobiao
2014-12-01
The fuel regression rate is an important parameter in the design process of the hybrid rocket motor. Additives in the solid fuel may have influences on the fuel regression rate, which will affect the internal ballistics of the motor. A series of firing experiments have been conducted on lab-scale hybrid rocket motors with 98% hydrogen peroxide (H2O2) oxidizer and hydroxyl terminated polybutadiene (HTPB) based fuels in this paper. An innovative fuel regression rate analysis method is established to diminish the errors caused by start and tailing stages in a short time firing test. The effects of the metal Mg, Al, aromatic hydrocarbon anthracene (C14H10), and carbon black (C) on the fuel regression rate are investigated. The fuel regression rate formulas of different fuel components are fitted according to the experiment data. The results indicate that the influence of C14H10 on the fuel regression rate of HTPB is not evident. However, the metal additives in the HTPB fuel can increase the fuel regression rate significantly.
Smitinont, T; Tansakul, C; Tanasupawat, S; Keeratipibul, S; Navarini, L; Bosco, M; Cescutti, P
1999-10-15
Lactic Acid Bacteria (LAB) isolated from various traditional Thai fermented foods were screened for exopolysaccharides (EPS) production. From 104 isolates, two rod-shaped and five coccal-shaped LAB were able to produce EPS from sucrose on solid media. However, only the cocci were capable of producing EPS in liquid media and these were identified as Pediococcus pentosaceus. Pediococcus pentosaceus strains AP-1 and AP-3 produced EPS in high yield. In liquid media containing sucrose as carbon source, the amount of EPS produced by AP-1 and AP-3 strains was 6.0 and 2.5 g/L, respectively. The isolated and purified EPSs were chemically characterized. On the basis of sugar composition, methylation analysis and nuclear magnetic resonance spectroscopy, both the EPSs were shown to belong to the same dextran class. In particular, both EPSs differed from linear dextran by branching through 3,6-di-Osubstituted alpha-D-glucopyranosyl residues. The EPS from P. pentosaceus AP-3 was characterized by a relatively higher degree of branching and by a higher molecular weight than that from P. pentosaceus AP-1.
NASA Astrophysics Data System (ADS)
Henry, William; Jefferson Lab Hall A Collaboration
2017-09-01
Jefferson Lab's cutting-edge parity-violating electron scattering program has increasingly stringent requirements for systematic errors. Beam polarimetry is often one of the dominant systematic errors in these experiments. A new Møller Polarimeter in Hall A of Jefferson Lab (JLab) was installed in 2015 and has taken first measurements for a polarized scattering experiment. Upcoming parity violation experiments in Hall A include CREX, PREX-II, MOLLER and SOLID with the latter two requiring <0.5% precision on beam polarization measurements. The polarimeter measures the Møller scattering rates of the polarized electron beam incident upon an iron target placed in a saturating magnetic field. The spectrometer consists of four focusing quadrapoles and one momentum selection dipole. The detector is designed to measure the scattered and knock out target electrons in coincidence. Beam polarization is extracted by constructing an asymmetry from the scattering rates when the incident electron spin is parallel and anti-parallel to the target electron spin. Initial data will be presented. Sources of systematic errors include target magnetization, spectrometer acceptance, the Levchuk effect, and radiative corrections which will be discussed. National Science Foundation.
Cassidy conducts BASS Flame Test
2013-04-09
ISS035-E-16429 (9 April 2013) --- Astronaut Chris Cassidy, Expedition 35 flight engineer, conducts a session of the Burning and Suppression of Solids (BASS) experiment located in the U.S. lab Destiny onboard the Earth-orbiting International Space Station. Cassidy over a period of several days, has conducted several "runs" of the experiment, which examines the burning and extinction characteristics of a wide variety of fuel samples in microgravity and will guide strategies for extinguishing fires in microgravity. BASS results contribute to the combustion computational models used in the design of fire detection and suppression systems in microgravity and on Earth.
High resolution 3D laboratory x-ray tomography data of femora from young, 1-14 day old C57BL/6 mice.
Bortel, Emely L; Duda, Georg N; Mundlos, Stefan; Willie, Bettina M; Fratzl, Peter; Zaslansky, Paul
2015-09-01
This data article contains high resolution (1.2 µm effective pixel size) lab-based micro-computed tomography (µCT) reconstructed volume data of the femoral mid-shafts from young C57BL/6 mice. This data formed the basis for the analyses of bone structural development in healthy mice, including closed and open porosity as reported in Bortel et al. [1]. The data reveals changes seen in bone material and porosity distribution observed when mouse bones transform from porous scaffolds into solid structures during normal organogenesis.
2001-01-17
Workers in the Payload Changeout Room check the Payload Ground Handling Mechanism that will move the U.S. Lab Destiny out of Atlantis’ payload bay and into the PCR. After the move, Atlantis will roll back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster’s system tunnel. An extensive evaluation of NASA’s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis
2001-01-17
The U.S. Lab Destiny begins moving out of Atlantis’ payload bay and into the Payload Changeout Room via the Payload Ground Handling Mechanism. Destiny will remain in the PCR while Atlantis rolls back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster’s system tunnel. An extensive evaluation of NASA’s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis
2001-01-17
The U.S. Lab Destiny moves out of Atlantis’ payload bay and into the Payload Changeout Room via the Payload Ground Handling Mechanism. Destiny will remain in the PCR while Atlantis rolls back to the Vehicle Assembly Building to allow workers to conduct inspections, continuity checks and X-ray analysis on the 36 solid rocket booster cables located inside each booster’s system tunnel. An extensive evaluation of NASA’s SRB cable inventory revealed conductor damage in four (of about 200) cables on the shelf. Shuttle managers decided to prove the integrity of the system tunnel cables already on Atlantis
Aerosol Delivery for Amendment Distribution in Contaminated Vadose Zones
NASA Astrophysics Data System (ADS)
Hall, R. J.; Murdoch, L.; Riha, B.; Looney, B.
2011-12-01
Remediation of contaminated vadose zones is often hindered by an inability to effectively distribute amendments. Many amendment-based approaches have been successful in saturated formations, however, have not been widely pursued when treating contaminated unsaturated materials due to amendment distribution limitations. Aerosol delivery is a promising new approach for distributing amendments in contaminated vadose zones. Amendments are aerosolized and injected through well screens. During injection the aerosol particles are transported with the gas and deposited on the surfaces of soil grains. Resulting distributions are radially and vertically broad, which could not be achieved by injecting pure liquid-phase solutions. The objectives of this work were A) to characterize transport and deposition behaviors of aerosols; and B) to develop capabilities for predicting results of aerosol injection scenarios. Aerosol transport and deposition processes were investigated by conducting lab-scale injection experiments. These experiments involved injection of aerosols through a 2m radius, sand-filled wedge. A particle analyzer was used to measure aerosol particle distributions with time, and sand samples were taken for amendment content analysis. Predictive capabilities were obtained by constructing a numerical model capable of simulating aerosol transport and deposition in porous media. Results from tests involving vegetable oil aerosol injection show that liquid contents appropriate for remedial applications could be readily achieved throughout the sand-filled wedge. Lab-scale tests conducted with aqueous aerosols show that liquid accumulation only occurs near the point of injection. Tests were also conducted using 200 g/L salt water as the aerosolized liquid. Liquid accumulations observed during salt water tests were minimal and similar to aqueous aerosol results. However, particles were measured, and salt deposited distal to the point of injection. Differences between aqueous and oil deposition are assumed to occur due to surface interactions, and susceptibility to evaporation of aqueous aerosols. Distal salt accumulation during salt water aerosol tests suggests that solid salt forms as salt water aerosols evaporate. The solid salt aerosols are less likely to deposit, so they travel further than aqueous aerosols. A numerical model was calibrated using results from lab-scale tests. The calibrated model was then used to simulate field-scale aerosol injection. Results from field-scale simulations suggest that effective radii of influence on the scale of 8-10 meters could be achieved in partially saturated sand. The aerosol delivery process appears to be capable distributing oil amendments over considerable volumes of formation at concentrations appropriate for remediation purposes. Thus far, evaporation has limited liquid accumulation observed when distributing aqueous aerosols, however, results from salt water experiments suggest that injection of solid phase aerosols can effectively distribute water soluble amendments (electron donor, pH buffer, oxidants, etc.). Utilization of aerosol delivery could considerably expand treatment options for contaminated vadose zones at a wide variety of sites.
NASA Astrophysics Data System (ADS)
Matter, John; Gnanvo, Kondo; Liyanage, Nilanga; Solid Collaboration; Moller Collaboration
2017-09-01
The JLab Parity Violation In Deep Inelastic Scattering (PVDIS) experiment will use the upgraded 12 GeV beam and proposed Solenoidal Large Intensity Device (SoLID) to measure the parity-violating electroweak asymmetry in DIS of polarized electrons with high precision in order to search for physics beyond the Standard Model. Unlike many prior Parity-Violating Electron Scattering (PVES) experiments, PVDIS is a single-particle tracking experiment. Furthermore the experiment's high luminosity combined with the SoLID spectrometer's open configuration creates high-background conditions. As such, the PVDIS experiment has the most demanding tracking detector needs of any PVES experiment to date, requiring precision detectors capable of operating at high-rate conditions in PVDIS's full production luminosity. Developments in large-area GEM detector R&D and SoLID simulations have demonstrated that GEMs provide a cost-effective solution for PVDIS's tracking needs. The integrating-detector-based JLab Measurement Of Lepton Lepton Electroweak Reaction (MOLLER) experiment requires high-precision tracking for acceptance calibration. Large-area GEMs will be used as tracking detectors for MOLLER as well. The conceptual designs of GEM detectors for the PVDIS and MOLLER experiments will be presented.
Santos, Inês C; Mesquita, Raquel B R; Rangel, António O S S
2015-09-03
This work describes the development of a solid phase spectrophotometry method in a μSI-LOV system for cadmium, zinc, and copper determination in freshwaters. NTA (Nitrilotriacetic acid) beads with 60-160 μm diameter were packed in the flow cell of the LOV for a μSPE column of 1 cm length. The spectrophotometric determination is based on the colourimetric reaction between dithizone and the target metals, previously retained on NTA resin. The absorbance of the coloured product formed is measured, at 550 nm, on the surface of the NTA resin beads in a solid phase spectrophotometry approach. The developed method presented preconcentration factors in the range of 11-21 for the metal ions. A LOD of 0.23 μg L(-1) for cadmium, 2.39 μg L(-1) for zinc, and 0.11 μg L(-1) for copper and a sampling rate of 12, 13, and 15 h(-1) for cadmium, zinc, and copper were obtained, respectively. The proposed method was successfully applied to freshwater samples. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Larson, Daniel B.; Boyer, Eric; Wachs, Trevor; Kuo, Kenneth, K.; Koo, Joseph H.; Story, George
2012-01-01
Paraffin-based solid fuels for hybrid rocket motor applications are recognized as a fastburning alternative to other fuel binders such as HTPB, but efforts to further improve the burning rate and mechanical properties of paraffin are still necessary. One approach that is considered in this study is to use multi-walled carbon nanotubes (MWNT) as an additive to paraffin wax. Carbon nanotubes provide increased electrical and thermal conductivity to the solid-fuel grains to which they are added, which can improve the mass burning rate. Furthermore, the addition of ultra-fine aluminum particles to the paraffin/MWNT fuel grains can enhance regression rate of the solid fuel and the density impulse of the hybrid rocket. The multi-walled carbon nanotubes also present the possibility of greatly improving the mechanical properties (e.g., tensile strength) of the paraffin-based solid-fuel grains. For casting these solid-fuel grains, various percentages of MWNT and aluminum particles will be added to the paraffin wax. Previous work has been published about the dispersion and mixing of carbon nanotubes.1 Another manufacturing method has been used for mixing the MWNT with a phenolic resin for ablative applications, and the manufacturing and mixing processes are well-documented in the literature.2 The cost of MWNT is a small fraction of single-walled nanotubes. This is a scale-up advantage as future applications and projects will require low cost additives to maintain cost effectiveness. Testing of the solid-fuel grains will be conducted in several steps. Dog bone samples will be cast and prepared for tensile testing. The fuel samples will also be analyzed using thermogravimetric analysis and a high-resolution scanning electron microscope (SEM). The SEM will allow for examination of the solid fuel grain for uniformity and consistency. The paraffin-based fuel grains will also be tested using two hybrid rocket test motors located at the Pennsylvania State University s High Pressure Combustion Lab.
NASA Astrophysics Data System (ADS)
Haryono, Didied; Harjanto, Sri; Wijaya, Rifky; Oediyani, Soesaptri; Nugraha, Harisma; Huda, Mahfudz Al; Taruno, Warsito Purwo
2018-04-01
Investigation of column flotation process on sulphide ore using 2-electrode capacitance sensor is presented in this paper. The effect of air flow rate and solid percentage on column flotation process has been experimentally investigated. The purpose of this paper is to understand the capacitance signal characteristic affected by the air flow rate and the solid percentage which can be used to determine the metallurgical performance. Experiments were performed using a laboratory column flotation cell which has a diameter of 5 cm and the total height of 140 cm. The sintered ceramic sparger and wash water were installed at the bottom and above of the column. Two-electrode concave type capacitance sensor was also installed at a distance of 50 cm from the sparger. The sensor was attached to the outer wall of the column, connected to data acquisition system, manufactured by CTECH Labs Edwar Technology and personal computer for further data processing. Feed consisting ZnS and SiO2 with the ratio of 3:2 was mixed with some reagents to make 1 litre of slurry. The slurry was fed into the aerated column at 100 cm above the sparger with a constant rate and the capacitance signals were captured during the process. In this paper, 7.5 and 10% of solid and 2-4 L/min of air flow rate with 0.5 L/min intervals were used as independent variables. The results show that the capacitance signal characteristics between the 7.5 and 10% of solid are different at any given air flow rate in which the 10% solid produced signals higher than those of 7.5%. Metallurgical performance and capacitance signal exhibit a good correlation.
Brandstätter, Christian; Laner, David; Fellner, Johann
2015-09-01
Nitrogen emissions from municipal solid waste (MSW) landfills occur primarily via leachate, where they pose a long-term pollution problem in the form of ammonium. In-situ aeration was proposed as a remediation measure to mitigate nitrogenous landfill emissions, turning the anaerobic environment to anoxic and subsequently aerobic. As in-depth studies of the nitrogen cycle during landfill aeration had been largely missing, it was the aim of this work to establish a detailed nitrogen balance for aerobic and anaerobic degradation of landfilled MSW based on lab-scale experiments, and also investigating the effect of different water regimes on nitrogen transformation during aeration. Six landfill simulation reactors were operated in duplicate under different conditions: aerated wet (with water addition and recirculation), aerated dry (without water addition) and anaerobic (wet). The results showed that more than 78 % of the initial total nitrogen (TNinit) remained in the solids in all set ups, with the highest nitrogen losses achieved with water addition during aeration. In this case, gaseous nitrogen losses (as N2 due to denitrification) amounted up to 16.6 % of TNinit and around 4 % of TNinit was discharged via leachate. The aerated dry set-up showed lower denitrification rates (2.6-8.8 % of TNinit was released as N2), but was associated with the highest N2O emissions (3.8-3.9 % of TNinit). For the anaerobic treatment the main pathway of nitrogen discharge was the leachate, where NH4 accounted for around 8 % of TNinit. These findings provide the basis for improved management strategies to enhance nitrogen removal during in-situ aeration of old landfills.
Towards an automatic lab-on-valve-ion mobility spectrometric system for detection of cocaine abuse.
Cocovi-Solberg, David J; Esteve-Turrillas, Francesc A; Armenta, Sergio; de la Guardia, Miguel; Miró, Manuel
2017-08-25
A lab-on-valve miniaturized system integrating on-line disposable micro-solid phase extraction has been interfaced with ion mobility spectrometry for the accurate and sensitive determination of cocaine and ecgonine methyl ester in oral fluids. The method is based on the automatic loading of 500μL of oral fluid along with the retention of target analytes and matrix clean-up by mixed-mode cationic/reversed-phase solid phase beads, followed by elution with 100μL of 2-propanol containing (3% v/v) ammonia, which are online injected into the IMS. The sorptive particles are automatically discarded after every individual assay inasmuch as the sorptive capacity of the sorbent material is proven to be dramatically deteriorated with reuse. The method provided a limit of detection of 0.3 and 0.14μgL -1 for cocaine and ecgonine methyl ester, respectively, with relative standard deviation values from 8 till 14% with a total analysis time per sample of 7.5min. Method trueness was evaluated by analyzing oral fluid samples spiked with cocaine at different concentration levels (1, 5 and 25μgL -1 ) affording relative recoveries within the range of 85±24%. Fifteen saliva samples were collected from volunteers and analysed following the proposed automatic procedure, showing a 40% cocaine occurrence with concentrations ranging from 1.3 to 97μgL -1 . Field saliva samples were also analysed by reference methods based on lateral flow immunoassay and gas chromatography-mass spectrometry. The application of this procedure to the control of oral fluids of cocaine consumers represents a step forward towards the development of a point-of-care cocaine abuse sensing system. Copyright © 2017 Elsevier B.V. All rights reserved.
Zhu, Mei; Yang, Zhenyu; Ren, Yiping; Duan, Yifan; Gao, Huiyu; Liu, Biao; Ye, Wenhui; Wang, Jie; Yin, Shian
2017-01-01
Macronutrient contents in human milk are the common basis for estimating these nutrient requirements for both infants and lactating women. A mid-infrared human milk analyser (HMA, Miris, Sweden) was recently developed for determining macronutrient levels. The purpose of the study is to compare the accuracy and precision of HMA method with fresh milk samples in the field studies with chemical methods with frozen samples in the lab. Full breast milk was collected using electric pumps and fresh milk was analyzed in the field studies using HMA. All human milk samples were thawed and analyzed with chemical reference methods in the lab. The protein, fat and total solid levels were significantly correlated between the two methods and the correlation coefficient was 0.88, 0.93 and 0.78, respectively (p < 0.001). The mean protein content was significantly lower and the mean fat level was significantly greater when measured using HMA method (1.0 g 100 mL -1 vs 1.2 g 100 mL -1 and 3. 7 g 100 mL -1 vs 3.2 g 100 mL -1 , respectively, p < 0.001). Thus, linear recalibration could be used to improve mean estimation for both protein and fat. There was no significant correlation for lactose between the two methods (p > 0.05). There was no statistically significant difference in the mean total solid concentration (12.2 g 100 mL -1 vs 12.3 g 100 mL -1 , p > 0.05). Overall, HMA might be used to analyze macronutrients in fresh human milk with acceptable accuracy and precision after recalibrating fat and protein levels of field samples. © 2016 John Wiley & Sons Ltd.
Oliveira, Hugo M; Segundo, Marcela A; Lima, José L F C; Miró, Manuel; Cerdà, Victor
2010-05-01
In the present work, it is proposed, for the first time, an on-line automatic renewable molecularly imprinted solid-phase extraction (MISPE) protocol for sample preparation prior to liquid chromatographic analysis. The automatic microscale procedure was based on the bead injection (BI) concept under the lab-on-valve (LOV) format, using a multisyringe burette as propulsion unit for handling solutions and suspensions. A high precision on handling the suspensions containing irregularly shaped molecularly imprinted polymer (MIP) particles was attained, enabling the use of commercial MIP as renewable sorbent. The features of the proposed BI-LOV manifold also allowed a strict control of the different steps within the extraction protocol, which are essential for promoting selective interactions in the cavities of the MIP. By using this on-line method, it was possible to extract and quantify riboflavin from different foodstuff samples in the range between 0.450 and 5.00 mg L(-1) after processing 1,000 microL of sample (infant milk, pig liver extract, and energy drink) without any prior treatment. For milk samples, LOD and LOQ values were 0.05 and 0.17 mg L(-1), respectively. The method was successfully applied to the analysis of two certified reference materials (NIST 1846 and BCR 487) with high precision (RSD < 5.5%). Considering the downscale and simplification of the sample preparation protocol and the simultaneous performance of extraction and chromatographic assays, a cost-effective and enhanced throughput (six determinations per hour) methodology for determination of riboflavin in foodstuff samples is deployed here.
NASA Astrophysics Data System (ADS)
Vergauwe, Nicolas; Witters, Daan; Ceyssens, Frederik; Vermeir, Steven; Verbruggen, Bert; Puers, Robert; Lammertyn, Jeroen
2011-05-01
Electrowetting-on-dielectric (EWOD) lab-on-a-chip systems have already proven their potential within a broad range of bio-assays. Nevertheless, research on the analytical performance of those systems is limited, yet crucial for a further breakthrough in the diagnostic field. Therefore, this paper presents the intrinsic possibilities of an EWOD lab-on-a-chip as a versatile platform for homogeneous and heterogeneous bio-assays with high analytical performance. Both droplet dispensing and splitting cause variations in droplet size, thereby directly influencing the assay's performance. The extent to which they influence the performance is assessed by a theoretical sensitivity analysis, which allows the definition of a basic framework for the reduction of droplet size variability. Taking advantage of the optimized droplet manipulations, both homogeneous and heterogeneous bio-assays are implemented in the EWOD lab-on-a-chip to demonstrate the analytical capabilities and versatility of the device. A fully on-chip enzymatic assay is realized with high analytical performance. It demonstrates the promising capabilities of an EWOD lab-on-a-chip in food-related and medical applications, such as nutritional and blood analyses. Further, a magnetic bio-assay for IgE detection using superparamagnetic nanoparticles is presented whereby the nanoparticles are used as solid carriers during the bio-assay. Crucial elements are the precise manipulation of the superparamagnetic nanoparticles with respect to dispensing and separation. Although the principle of using nano-carriers is demonstrated for protein detection, it can be easily extended to a broader range of bio-related applications like DNA sensing. In heterogeneous bio-assays the chip surface is actively involved during the execution of the bio-assay. Through immobilization of specific biological compounds like DNA, proteins and cells a reactive chip surface is realized, which enhances the bio-assay performance. To demonstrate this potential, on-chip adhesion islands are fabricated to immobilize MCF-7 human breast cancer cells. Viability studies are performed to assess the functionalization efficiency.
NASA Technical Reports Server (NTRS)
Hutchens, Dale E.; Doan, Patrick A.; Boothe, Richard E.
1997-01-01
Bonding labs at both MSFC and the northern Utah production plant prepare bond test specimens which simulate or witness the production of NASA's Reusable Solid Rocket Motor (RSRM). The current process for preparing the bonding surfaces employs 1,1,1-trichloroethane vapor degreasing, which simulates the current RSRM process. Government regulations (e.g., the 1990 Amendments to the Clean Air Act) have mandated a production phase-out of a number of ozone depleting compounds (ODC) including 1,1,1-trichloroethane. In order to comply with these regulations, the RSRM Program is qualifying a spray-in-air (SIA) precision cleaning process using Brulin 1990, an aqueous blend of surfactants. Accordingly, surface preparation prior to bonding process simulation test specimens must reflect the new production cleaning process. The Bonding Lab Statistical Process Control (SPC) program monitors the progress of the lab and its capabilities, as well as certifies the bonding technicians, by periodically preparing D6AC steel tensile adhesion panels with EA-91 3NA epoxy adhesive using a standardized process. SPC methods are then used to ensure the process is statistically in control, thus producing reliable data for bonding studies, and identify any problems which might develop. Since the specimen cleaning process is being changed, new SPC limits must be established. This report summarizes side-by-side testing of D6AC steel tensile adhesion witness panels and tapered double cantilevered beams (TDCBs) using both the current baseline vapor degreasing process and a lab-scale spray-in-air process. A Proceco 26 inches Typhoon dishwasher cleaned both tensile adhesion witness panels and TDCBs in a process which simulates the new production process. The tests were performed six times during 1995, subsequent statistical analysis of the data established new upper control limits (UCL) and lower control limits (LCL). The data also demonstrated that the new process was equivalent to the vapor degreasing process.
NASA Astrophysics Data System (ADS)
Galkin, A.; Klump, J.; Wiedenbeck, M.
2012-04-01
Secondary Ion Mass Spectrometers (SIMS) is an highly sensitive technique for analyzing the surfaces of solids and thin film samples, but has the major drawback that such instruments are both rare and expensive. The Virtual SIMS project aims to design, develop and operate the IT infrastructure around the CAMECA IMS 1280-HR SIMS at GFZ Potsdam. The system will cover the whole spectrum of the procedures in the lab - from the online application for measurement time, to the remote access to the instrument and finally the maintenance of the data for publishing and future re-use. A virtual lab infrastructure around the IMS 1280 will enable remote access to the instrument and make measurement time available to the broadest possible user community. Envisioned is that the IT infrastructure would consist of the following: web portal, data repository, sample repository, project management software, communication arrangements between the lab staff and distant researcher and remote access to the instruments. The web portal will handle online applications for the measurement time. The data from the experiments, the monitoring sensor logs and the lab logbook entries are to be stored and archived. Researchers will be able to access their data remotely in real time, thus imposing a user rights management strucuture. Also planned is that all samples and the standards will be assigned a unique International GeoSample Number (IGSN) and that the images of the samples will be stored and made accessible in addition to any additional documents which might be uploaded by the researcher. The project management application will schedule the application process, the measurements times, notifications and alerts. A video conference capability is forseen for communication between the Potsdam staff and the remote researcher. The remote access to the instruments requires a sophisticated client-server solution. This highly sensitive instrument has to be controlled in real-time with latencies diminished to a minimum. Also, failures and shortages of the internet connection, as well as possible outages on the client side, have to be considered and safe fallbacks for such events must be provided. The level of skills of the researcher remotely operating the instrument will define the scope of control given during an operating session. An important aspect of the project is the design of the virtual lab system in collaboration with the laboratory operators and the researchers who will use the instrument and its peripherals. Different approaches for the IT solutions will be tested and evaluated, so imporved guidelines can evolve from obsperved operating performance.
McLeod, James; Othman, Maazuza Z; Parthasarathy, Rajarathinam
2018-05-26
The relationship between mixing energy input and biogas production was investigated by anaerobically digesting sewage sludge in lab scale, hydraulically mixed, batch mode digesters at six different specific energy inputs. The goal was to identify how mixing energy influenced digestion performance at quantitative levels to help explain the varying results in other published works. The results showed that digester homogeneity was largely uninfluenced by energy input, whereas cumulative biogas production and solids destruction were. With similar solids distributions between conditions, the observed differences were attributed to shear forces disrupting substrate-microbe flocs rather than the formation of temperature and/or concentration gradients. Disruption of the substrate-microbe flocs produced less favourable conditions for hydrolytic bacteria, resulting in less production of biomass and more biogas. Overall, this hypothesis explains the current body of research including the inhibitory conditions reported at extreme mixing power inputs. However, further work is required to definitively prove it. Copyright © 2018 Elsevier Ltd. All rights reserved.
Failure analysis of electrolyte-supported solid oxide fuel cells
NASA Astrophysics Data System (ADS)
Fleischhauer, Felix; Tiefenauer, Andreas; Graule, Thomas; Danzer, Robert; Mai, Andreas; Kuebler, Jakob
2014-07-01
For solid oxide fuel cells (SOFCs) one key aspect is the structural integrity of the cell and hence its thermo mechanical long term behaviour. The present study investigates the failure mechanisms and the actual causes for fracture of electrolyte supported SOFCs which were run using the current μ-CHP system of Hexis AG, Winterthur - Switzerland under lab conditions or at customer sites for up to 40,000 h. In a first step several operated stacks were demounted for post-mortem inspection, followed by a fractographic evaluation of the failed cells. The respective findings are then set into a larger picture including an analysis of the present stresses acting on the cell like thermal and residual stresses and the measurements regarding the temperature dependent electrolyte strength. For all investigated stacks, the mechanical failure of individual cells can be attributed to locally acting bending loads, which rise due to an inhomogeneous and uneven contact between the metallic interconnect and the cell.
Prantl, R; Tesar, M; Huber-Humer, M; Lechner, P
2006-01-01
Emissions from old landfills via leachate and the gas phase are influenced by state and stability of the organic matter in the solid waste and by environmental conditions within the landfill. Remediation of landfills by means of in-situ aeration is one possibility to reduce these emissions. By establishing aerobic conditions, biological processes in the landfill are accelerated. To investigate the effects of this remediation technology, lab-scale experiments with column tests have been carried out. The main goal of the present work is to characterize the changes of the carbon and nitrogen compounds in the aerated solid waste, the leachate and the gas phase under varying conditions. The results demonstrate a clear reduction of emissions and a stabilization of the organic matter. Furthermore, it is shown that both the intensity of aeration and the amount of water affect biological processes to a certain extent. Even when columns were operated under anaerobic conditions after a long running period of aeration, the emissions remained low.
Flexible packaging of solid-state integrated circuit chips with elastomeric microfluidics
Zhang, Bowei; Dong, Quan; Korman, Can E.; Li, Zhenyu; Zaghloul, Mona E.
2013-01-01
A flexible technology is proposed to integrate smart electronics and microfluidics all embedded in an elastomer package. The microfluidic channels are used to deliver both liquid samples and liquid metals to the integrated circuits (ICs). The liquid metals are used to realize electrical interconnects to the IC chip. This avoids the traditional IC packaging challenges, such as wire-bonding and flip-chip bonding, which are not compatible with current microfluidic technologies. As a demonstration we integrated a CMOS magnetic sensor chip and associate microfluidic channels on a polydimethylsiloxane (PDMS) substrate that allows precise delivery of small liquid samples to the sensor. Furthermore, the packaged system is fully functional under bending curvature radius of one centimetre and uniaxial strain of 15%. The flexible integration of solid-state ICs with microfluidics enables compact flexible electronic and lab-on-a-chip systems, which hold great potential for wearable health monitoring, point-of-care diagnostics and environmental sensing among many other applications.
Accelerating CR-39 Track Detector Processing by Utilizing UV
NASA Astrophysics Data System (ADS)
Sparling, Jonathan; Padalino, Stephen; McLean, James; Sangster, Craig; Regan, Sean
2017-10-01
The use of CR-39 plastic as a Solid State Nuclear Track Detector is an effective technique for obtaining data in high energy particle experiments including inertial confinement fusion. To reveal particle tracks after irradiation, CR-39 is chemically etched in NaOH at 80°C, producing micron-scale signal pits at the nuclear track sites. It has been shown that illuminating CR-39 with UV light prior to etching increases bulk and track etch rates, especially when combined with elevated temperature. Spectroscopic analysis for amorphous solids has helped identify which UV wavelengths are most effective at enhancing etch rates. Absorption peaks found in the near infrared range provide for efficient sample heating, and may allow targeting cooperative IR-UV chemistry. Avoiding UV induced noise can be achieved through variations in absorption depths with wavelength. Vacuum drying and water absorption tests allow measurement of the resulting variation of bulk etch rate with depth. Funded in part by the NSF and an Department of Energy Grant through the Lab of Laser Energetics.
NASA Astrophysics Data System (ADS)
Perera, Gonaduwage; Johnson, Ian; Keller, Dustin
2017-09-01
Dynamic Nuclear Polarization (DNP) is used in most of the solid polarized target scattering experiments. Those target materials must be irradiated using microwaves at a frequency determined by the difference in the nuclear Larmor and electron paramagnetic resonance (EPR) frequencies. But the resonance frequency changes with time as a result of radiation damage. Hence the microwave frequency should be adjusted accordingly. Manually adjusting the frequency can be difficult, and improper adjustments negatively impact the polarization. In order to overcome these difficulties, two controllers were developed which automate the process of seeking and maintaining the optimal frequency: one being a standalone controller for a traditional DC motor and the other a LabVIEW VI for a stepper motor configuration. Further a Monte-Carlo simulation was developed which can accurately model the polarization over time as a function of microwave frequency. In this talk, analysis of the simulated data and recent improvements to the automated system will be presented. DOE.
2000-12-04
Atlantis rolls into the transfer aisle of the Vehicle Assembly Building where it will be raised to vertical and lifted into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
2000-12-04
Atlantis rolls into the transfer aisle of the Vehicle Assembly Building where it will be raised to vertical and lifted into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
NASA Technical Reports Server (NTRS)
Youngquist, Robert C.; Starr, Stanley O.; Stevenson, G.; Rivera, Jorge E.; Sullivan, Steven J.
2011-01-01
For over 30 years the Kennedy Space Center (KSC) has processed the Space Shuttle; handling all hands-on aspects from receiving the Orbiter, External Tanks, Solid Rocket Booster Segments, and Payloads, through certification, check-out, and assembly, and ending with fueling, count-down, and launch. A team of thousands have worked this highly complicated, yet supremely organized, process and have, as a consequence, generated an exceptional amount of technology to solve a host of problems. This paper describes the contributions of one team that formed with the express purpose to help solve some of these diverse Shuttle ground processing problems.
Wett, B; Eladawy, A; Becker, W
2003-01-01
The impact of marble powder on the performance of small seasonal treatment plants dealing with high ammonia concentrated wastewater has been investigated. The carbonate has been added to one of two parallel lab-scale SBR-systems as an alkalinity depot and a bio-carrier. The focus of the monitoring program was put on the measurement of carbon fractions in the liquid and the solid phase and on the alkalinity conditions. Monitoring results show a significant correlation between carbonate dosage (and corresponding inorganic carbon concentration and pH-value) and sludge volume index and nitrification rate.
Biochips: A fruitful product of solid state physics and molecular biology
NASA Astrophysics Data System (ADS)
Mendoza-Alvarez, Julio G.
1998-08-01
The application of the standard high resolution photolithography techniques used in the semiconductor device industry to the growth of a chain of nucleotides with a precise and well known sequence, has made possible the fabrication of a new kind of device, the so called biochips. At the National Polytechnic Institute in Mexico we have joined a multidisciplinary scientific group, and we are in the process of developing the technical capabilities in order to set up a processing lab to fabricate biochips focused to very specific applications in the area of cancer detection. We present here the main lines along which this project is being developed.
Blondeel, E; Chys, M; Depuydt, V; Folens, K; Du Laing, G; Verliefde, A; Van Hulle, S W H
2014-12-01
Scrap material recovery and recycling companies are confronted with waste water that has a highly fluctuating flow rate and composition. Common pollutants, such as COD, nutrients and suspended solids, potentially toxic metals, polyaromatic hydrocarbons and poly chlorinated biphenyls can exceed the discharge limits. An analysis of the leaching behaviour of different scrap materials and scrap yard sweepings was performed at full-scale, pilot-scale and lab-scale in order to find possible preventive solutions for this waste water problem. The results of these leaching tests (with concentrations that frequently exceeded the Flemish discharge limits) showed the importance of regular sweeping campaigns at the company, leak proof or covered storage of specific scrap materials and oil/water separation on particular leachates. The particulate versus dissolved fraction was also studied for the pollutants. For example, up to 98% of the polyaromatic hydrocarbons, poly chlorinated biphenyls and some metals were in the particulate form. This confirms the (potential) applicability of sedimentation and filtration techniques for the treatment of the majority of the leachates, and as such the rainwater run-off as a whole. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
McMullen, Timothy; Liyanage, Nilanga; Xiong, Weizhi; Zhao, Zhiwen
2017-01-01
Our research has focused on simulating the response of a Gas Electron Multiplier (GEM) detector using computational methods. GEM detectors provide a cost effective solution for radiation detection in high rate environments. A detailed simulation of GEM detector response to radiation is essential for the successful adaption of these detectors to different applications. Using Geant4 Monte Carlo (GEMC), a wrapper around Geant4 which has been successfully used to simulate the Solenoidal Large Intensity Device (SoLID) at Jefferson Lab, we are developing a simulation of a GEM chamber similar to the detectors currently used in our lab. We are also refining an object-oriented digitization program, which translates energy deposition information from GEMC into electronic readout which resembles the readout from our physical detectors. We have run the simulation with beta particles produced by the simulated decay of a 90Sr source, as well as with a simulated bremsstrahlung spectrum. Comparing the simulation data with real GEM data taken under similar conditions is used to refine the simulation parameters. Comparisons between results from the simulations and results from detector tests will be presented.
Influence of different propellant systems on ablation of EPDM insulators in overload state
NASA Astrophysics Data System (ADS)
Guan, Yiwen; Li, Jiang; Liu, Yang; Xu, Tuanwei
2018-04-01
This study examines the propellants used in full-scale solid rocket motors (SRM) and investigates how insulator ablation is affected by two propellant formulations (A and B) during flight overload conditions. An experimental study, theoretical analysis, and numerical simulations were performed to discover the intrinsic causes of insulator ablation rates from the perspective of lab-scaled ground-firing tests, the decoupling of thermochemical ablation, and particle erosion. In addition, the difference in propellant composition, and the insulator charring layer microstructure were analyzed. Results reveal that the degree of insulator ablation is positively correlated with the propellant burn rate, particle velocity, and aggregate concentrations during the condensed phase. A lower ratio of energetic additive material in the AP oxidizer of the propellant is promising for the reduction in particle size and increase in the burn rate and pressure index. However, the overall higher velocity of a two-phase flow causes severe erosion of the insulation material. While the higher ratio of energetic additive to the AP oxidizer imparts a smaller ablation rate to the insulator (under lab-scale test conditions), the slag deposition problem in the combustion chamber may cause catastrophic consequences for future large full-scale SRM flight experiments.
NASA Astrophysics Data System (ADS)
Valder, J.; Kenner, S.; Long, A.
2008-12-01
Portions of the Cheyenne River are characterized as impaired by the U.S. Environmental Protection Agency because of water-quality exceedences. The Cheyenne River watershed includes the Black Hills National Forest and part of the Badlands National Park. Preliminary analysis indicates that the Badlands National Park is a major contributor to the exceedances of the water-quality constituents for total dissolved solids and total suspended solids. Water-quality data have been collected continuously since 2007, and in the second year of collection (2008), monthly grab and passive sediment samplers are being used to collect total suspended sediment and total dissolved solids in both base-flow and runoff-event conditions. In addition, sediment samples from the river channel, including bed, bank, and floodplain, have been collected. These samples are being analyzed at the South Dakota School of Mines and Technology's X-Ray Diffraction Lab to quantify the mineralogy of the sediments. A multivariate statistical approach (including principal components, least squares, and maximum likelihood techniques) is applied to the mineral percentages that were characterized for each site to identify the contributing source areas that are causing exceedances of sediment transport in the Cheyenne River watershed. Results of the multivariate analysis demonstrate the likely sources of solids found in the Cheyenne River samples. A further refinement of the methods is in progress that utilizes a conceptual model which, when applied with the multivariate statistical approach, provides a better estimate for sediment sources.
Rani, R Uma; Kumar, S Adish; Kaliappan, S; Yeom, Ick-Tae; Banu, J Rajesh
2014-05-01
High efficiency resource recovery from dairy waste activated sludge (WAS) has been a focus of attention. An investigation into the influence of two step sono-alkalization pretreatment (using different alkaline agents, pH and sonic reaction times) on sludge reduction potential in a semi-continuous anaerobic reactor was performed for the first time in literature. Firstly, effect of sludge pretreatment was evaluated by COD solubilization, suspended solids reduction and biogas production. At optimized condition (4172 kJ/kg TS of supplied energy for NaOH - pH 10), COD solubilization, suspended solids reduction and biogas production was 59%, 46% and 80% higher than control. In order to clearly describe the hydrolysis of waste activated sludge during sono-alkalization pretreatment by a two step process, concentrations of ribonucleic acid (RNA) and bound extracellular polymeric substance (EPS) were also measured. Secondly, semi-continuous process performance was studied in a lab-scale semi-continuous anaerobic reactor (5L), with 4 L working volume. With three operated SRTs, the SRT of 15 d was found to be most appropriate for economic operation of the reactor. Combining pretreatment with anaerobic digestion led to 58% and 62% of suspended solids and volatile solids reduction, respectively, with an improvement of 83% in biogas production. Thus, two step sono-alkalization pretreatment laid the basis in enhancing the anaerobic digestion potential of dairy WAS. Copyright © 2013 Elsevier B.V. All rights reserved.
Organic Lasers: Recent Developments on Materials, Device Geometries, and Fabrication Techniques.
Kuehne, Alexander J C; Gather, Malte C
2016-11-09
Organic dyes have been used as gain medium for lasers since the 1960s, long before the advent of today's organic electronic devices. Organic gain materials are highly attractive for lasing due to their chemical tunability and large stimulated emission cross section. While the traditional dye laser has been largely replaced by solid-state lasers, a number of new and miniaturized organic lasers have emerged that hold great potential for lab-on-chip applications, biointegration, low-cost sensing and related areas, which benefit from the unique properties of organic gain materials. On the fundamental level, these include high exciton binding energy, low refractive index (compared to inorganic semiconductors), and ease of spectral and chemical tuning. On a technological level, mechanical flexibility and compatibility with simple processing techniques such as printing, roll-to-roll, self-assembly, and soft-lithography are most relevant. Here, the authors provide a comprehensive review of the developments in the field over the past decade, discussing recent advances in organic gain materials, which are today often based on solid-state organic semiconductors, as well as optical feedback structures, and device fabrication. Recent efforts toward continuous wave operation and electrical pumping of solid-state organic lasers are reviewed, and new device concepts and emerging applications are summarized.
NASA Technical Reports Server (NTRS)
Haynes, Jared; Kenny, R. Jeremy
2010-01-01
Recently, members of the Marshall Space Flight Center (MSFC) Fluid Dynamics Branch and Wyle Labs measured far-field acoustic data during a series of three Reusable Solid Rocket Motor (RSRM) horizontal static tests conducted in Promontory, Utah. The test motors included the Technical Evaluation Motor 13 (TEM-13), Flight Verification Motor 2 (FVM-2), and the Flight Simulation Motor 15 (FSM-15). Similar far-field data were collected during horizontal static tests of sub-scale solid rocket motors at MSFC. Far-field acoustical measurements were taken at multiple angles within a circular array centered about the nozzle exit plane, each positioned at a radial distance of 80 nozzle-exit-diameters from the nozzle. This type of measurement configuration is useful for calculating rocket noise characteristics such as those outlined in the NASA SP-8072 "Acoustic Loads Generated by the Propulsion System." Acoustical scaling comparisons are made between the test motors, with particular interest in the Overall Sound Power, Acoustic Efficiency, Non-dimensional Relative Sound Power Spectrum, and Directivity. Since most empirical data in the NASA SP-8072 methodology is derived from small rockets, this investigation provides an opportunity to check the data collapse between a sub-scale and full-scale rocket motor.
Measurement and Characterization of Space Shuttle Solid Rocket Motor Plume Acoustics
NASA Technical Reports Server (NTRS)
Kenny, Robert Jeremy
2009-01-01
NASA's current models to predict lift-off acoustics for launch vehicles are currently being updated using several numerical and empirical inputs. One empirical input comes from free-field acoustic data measured at three Space Shuttle Reusable Solid Rocket Motor (RSRM) static firings. The measurements were collected by a joint collaboration between NASA - Marshall Space Flight Center, Wyle Labs, and ATK Launch Systems. For the first time NASA measured large-thrust solid rocket motor plume acoustics for evaluation of both noise sources and acoustic radiation properties. Over sixty acoustic free-field measurements were taken over the three static firings to support evaluation of acoustic radiation near the rocket plume, far-field acoustic radiation patterns, plume acoustic power efficiencies, and apparent noise source locations within the plume. At approximately 67 m off nozzle centerline and 70 m downstream of the nozzle exit plan, the measured overall sound pressure level of the RSRM was 155 dB. Peak overall levels in the far field were over 140 dB at 300 m and 50-deg off of the RSRM thrust centerline. The successful collaboration has yielded valuable data that are being implemented into NASA's lift-off acoustic models, which will then be used to update predictions for Ares I and Ares V liftoff acoustic environments.
NASA Astrophysics Data System (ADS)
Conver, Timothy S.; Koropchak, John A.
1995-06-01
This paper describes detailed work done in our lab to compare analytical figures of merit for pneumatic, ultrasonic and thermospray sample introduction (SI) systems with three different inductively coupled plasma-atomic emission spectrometry (ICP-AES) instruments. One instrument from Leeman Labs, Inc. has an air path echelle spectrometer and a 27 MHz ICP. For low dissolved solid samples with this instrument, we observed that the ultrasonic nebulizer (USN) and fused silica aperture thermospray (FSApT) both offered similar LOD improvements as compared to pneumatic nebulization (PN), 14 and 16 times, respectively. Average sensitivities compared to PN were better for the USN, by 58 times, compared to 39 times for the FSApT. For solutions containing high dissolved solids we observed that FSApT optimized at the same conditions as for low dissolved solids, whereas USN required changes in power and gas flows to maintain a stable discharge. These changes degraded the LODs for USN substantially as compared to those utilized for low dissolved solid solutions, limiting improvement compared to PN to an average factor of 4. In general, sensitivities for USN were degraded at these new conditions. When solutions with 3000 μg/g Ca were analyzed, LOD improvements were smaller for FSApT and USN, but FSApT showed an improvement over USN of 6.5 times. Sensitivities compared to solutions without high dissolved solids were degraded by 19% on average for FSApT, while those for USN were degraded by 26%. The SI systems were also tested with a Varian Instruments Liberty 220 having a vacuum path Czerny-Turner monochromator and a 40 MHz generator. The sensitivities with low dissolved solids solutions compared to PN were 20 times better for the USN and 39 times better for FSApT, and LODs for every element were better for FSApT. Better correlation between relative sensitivities and anticipated relative analyte mass fluxes for FSApT and USN was observed with the Varian instrument. LOD improvements averaged 18 times lower than PN with FSApT while with USN values averaged 8 times lower. When solutions with high dissolved solids were studied it was found that FSApT still offered 5.5 times better LODs than PN and USN offered 4.6 times better LODs than PN. Sensitivities for FSApT averaged 20 times better, while those for USN were 13 times better compared to PN. Finally, background RSDs on the Varian system were generally higher for FSApT than for the USN for similar sample types. A third instrument used for a small set of elements was a Perkin-Elmer model 5500 ICP-AES. This system has a 27 MHz generator with a N 2 purged Czerny-Turner monochromator. LOD trends, background RSDs, and sensitivities were similar to those with the Leeman instrument. However, matrix effects more closely resembled those seen with the Varian instrument for both SI systems. To compare performance and recoveries on a real sample, a National Institute of Standards and Technology, Standard Reference Material 1643c trace elements in water, was analyzed using the Varian system and it was found that both SI systems offered similar recoveries.
Rivetti, Claudia; Gómez-Canela, Cristian; Lacorte, Silvia; Díez, Sergi; Lázaro, Wilkinson L; Barata, Carlos
2015-04-01
Identifying chemicals causing adverse effects in organisms present in water remains a challenge in environmental risk assessment. This study aimed to assess and identify toxic compounds bound to suspended solids re-suspended during a prolonged period of flushing flows in the lower part of Ebro River (NE, Spain). This area is contaminated with high amounts of organochlorine and mercury sediment wastes. Chemical characterization of suspended material was performed by solid phase extraction using a battery of non-polar and polar solvents and analyzed by GC-MS/MS and LC-MS/MS. Mercury content was also determined for all sites. Post-exposure feeding rates of Daphnia magna were used to assess toxic effects of whole and filtered water samples and of re-constituted laboratory water with re-suspended solid fractions. Organochlorine and mercury residues in the water samples increased from upstream to downstream locations. Conversely, toxic effects were greater at the upstream site than downstream of the superfund Flix reservoir. A further analysis of the suspended solid fraction identified a toxic component eluted within the 80:20 methanol:water fraction. Characterization of that toxic component fraction by LC-MS/MS identified the phytotoxin anatoxin-a, whose residue levels were correlated with observed feeding inhibition responses. Further feeding inhibition assays conducted in the lab using anatoxin-a produced from Planktothrix agardhii, a filamentous cyanobacteria, confirmed field results. This study provides evidence that in real field situation measured contaminant residues do not always agree with toxic effects. Copyright © 2015 Elsevier B.V. All rights reserved.
2000-12-04
Inside Orbiter Processing Facility bay 3, Atlantis is ready for rollover to the Vehicle Assembly Building. In the VAB it will be raised to vertical and lifted up and into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
2000-12-04
Inside Orbiter Processing Facility bay 3, Atlantis is ready for rollover to the Vehicle Assembly Building. In the VAB it will be raised to vertical and lifted up and into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
Think Scientifically: Hiding Science in a Storybook
NASA Astrophysics Data System (ADS)
Van Norden, W. M.; Wawro, M.
2013-12-01
The pressure to focus on math and reading at the elementary level has increased in recent years. As a result, science education has taken a back seat in elementary classrooms. The Think Scientifically book series provides a way for science to easily integrate with existing math and reading curriculum. This story-based science literature program integrates a classic storybook format with solid solar science, to make an educational product that meets state literacy standards. Each story is accompanied by hands-on labs and activities that teachers can easily conduct in their classrooms with minimal training and materials, as well as math and language arts extensions and assessment questions. These books are being distributed through teacher workshops and conferences.
Effects of die quench forming on sheet thinning and 3-point bend testing of AA7075-T6
NASA Astrophysics Data System (ADS)
Kim, Samuel; Omer, Kaab; Rahmaan, Taamjeed; Butcher, Clifford; Worswick, Michael
2017-10-01
Lab-scaled AA7075 aluminum side impact beams were manufactured using the die quenching technique in which the sheet was solutionized and then quenched in-die during forming to a super saturated solid state. Sheet thinning measurements were taken at various locations throughout the length of the part and the effect of lubricant on surface scoring and material pick-up on the die was evaluated. The as-formed beams were subjected to a T6 aging treatment and then tested in three-point bending. Simulations were performed of the forming and mechanical testing experiments using the LS-DYNA finite element code. The thinning and mechanical response was predicted well.
Recent advances of controlled drug delivery using microfluidic platforms.
Sanjay, Sharma T; Zhou, Wan; Dou, Maowei; Tavakoli, Hamed; Ma, Lei; Xu, Feng; Li, XiuJun
2018-03-15
Conventional systematically-administered drugs distribute evenly throughout the body, get degraded and excreted rapidly while crossing many biological barriers, leaving minimum amounts of the drugs at pathological sites. Controlled drug delivery aims to deliver drugs to the target sites at desired rates and time, thus enhancing the drug efficacy, pharmacokinetics, and bioavailability while maintaining minimal side effects. Due to a number of unique advantages of the recent microfluidic lab-on-a-chip technology, microfluidic lab-on-a-chip has provided unprecedented opportunities for controlled drug delivery. Drugs can be efficiently delivered to the target sites at desired rates in a well-controlled manner by microfluidic platforms via integration, implantation, localization, automation, and precise control of various microdevice parameters. These features accordingly make reproducible, on-demand, and tunable drug delivery become feasible. On-demand self-tuning dynamic drug delivery systems have shown great potential for personalized drug delivery. This review presents an overview of recent advances in controlled drug delivery using microfluidic platforms. The review first briefly introduces microfabrication techniques of microfluidic platforms, followed by detailed descriptions of numerous microfluidic drug delivery systems that have significantly advanced the field of controlled drug delivery. Those microfluidic systems can be separated into four major categories, namely drug carrier-free micro-reservoir-based drug delivery systems, highly integrated carrier-free microfluidic lab-on-a-chip systems, drug carrier-integrated microfluidic systems, and microneedles. Microneedles can be further categorized into five different types, i.e. solid, porous, hollow, coated, and biodegradable microneedles, for controlled transdermal drug delivery. At the end, we discuss current limitations and future prospects of microfluidic platforms for controlled drug delivery. Copyright © 2017 Elsevier B.V. All rights reserved.
Zhang, Chang-Ping; Gu, Ping; Zhao, Jun; Zhang, Dong; Deng, Yue
2009-08-15
The removal of cesium from an aqueous solution by an adsorption-microfiltration (AMF) process was investigated in jar tests and lab-scale tests. The adsorbent was K(2)Zn(3)[Fe(CN)(6)](2). The obtained cesium data in the jar test fit a Freundlich-type isotherm well. In the lab-scale test, the mean cesium concentration of the raw water and the effluent were 106.87 microg/L and 0.59 microg/L, respectively, the mean removal of cesium was 99.44%, and the mean decontamination factors (DF) and concentration factors (CF) were 208 and 539, respectively. The removal of cesium in the lab-scale test was better than that in the jar test because the old adsorbents remaining in the reactor still had adsorption capacity with the premise of no significant desorption being observed, and the continuous renewal of the adsorbent surface improved the adsorption capacity of the adsorbent. Some of the suspended solids were deposited on the bottom of the reactor, which would affect the mixing of adsorbents with the raw water and the renewing of the adsorbent surface. Membrane fouling was the main physical fouling mechanism, and the cake layer was the main filtration resistance. Specific flux (SF) decreased step by step during the whole period of operation due to membrane fouling and concentration polarization. The quality of the effluent was good and the turbidity remained lower than 0.1NTU, and the toxic anion, CN(-), could not be detected because of its low concentration, this indicated that the effluent was safe. The AMF process was feasible for practical application in the treatment of liquid waste containing cesium.
Growth characterization of individual rye sourdough bacteria by isothermal microcalorimetry.
Mihhalevski, A; Sarand, I; Viiard, E; Salumets, A; Paalme, T
2011-02-01
The present work tests the feasibility of the isothermal microcalorimetry method to study the performance of individual lactic acid bacteria during solid-state fermentation in rye sourdough. Another aim was to elucidate the key factors leading to the formation of different microbial consortia in laboratory and industrial sourdough during continuous backslopping propagation. Strains of the individual LAB isolated from industrial and laboratory sourdough cycle were grown in 10 kGy irradiated rye dough in vials of an isothermal calorimeter and the power-time curves were obtained. Sugars, organic acids and free amino acids in the sourdough were measured. The OD-time curves of the LAB strains during growth in flour extract or MRS (De Man, Rogosa and Sharpe) broth were also determined. The maximum specific growth rates of Lactobacillus sakei, Lactobacillus brevis, Lactobacillus curvatus and Leuconostoc citreum strains that dominated in backslopped laboratory sourdough were higher than those of Lactobacillus helveticus, Lactobacillus panis, Lactobacillus vaginalis, Lactobacillus casei and Lactobacillus pontis strains originating from industrial sourdough. Industrial strains had higher specific growth rates below pH 4·8. It was supposed that during long-run industrial backslopping processes, the oxygen sensitive species start to dominate because of the O(2) protective effect of rye sourdough. Measurements of the power-time curves revealed that the LAB strains dominating in the industrial sourdough cycle had better acid tolerance but lower maximum growth rate and oxygen tolerance than species isolated from a laboratory sourdough cycle. Isothermal microcalorimetry combined with chemical analysis is a powerful method for characterization of sourdough fermentation process and determination of growth characteristics of individual bacteria in sourdough. © 2010 The Authors. Journal of Applied Microbiology © 2010 The Society for Applied Microbiology.
NASA Astrophysics Data System (ADS)
Shu, Zhe; Pabst, Oliver; Beckert, Erik; Eberhardt, Ramona; Tünnermann, Andreas
2016-02-01
Microfluidic lab-on-chip devices can be used for chemical and biological analyses such as DNA tests or environmental monitoring. Such devices integrate most of the basic functionalities needed for scientific analysis on a microfluidic chip. When using such devices, cost and space-intensive lab equipment is no longer necessary. However, in order to make a monolithic and cost-efficient/disposable microfluidic sensing device, direct integration of the excitation light source for fluorescent sensing is often required. To achieve this, we introduce a fully solution processable deviation of OLEDs, organic light-emitting electrochemical cells (OLECs), as a low-cost excitation light source for a disposable microfluidic sensing platform. By mixing metal ions and a solid electrolyte with light-emitting polymers as active materials, an in-situ doping and in-situ PN-junction can be generated within a three layer sandwich device. Thanks to this doping effect, work function adaptation is not necessary and air-stable electrode can be used. An ambient manufacturing process for fully solution-processed OLECs is presented, which consist of a spin-coated blue light-emitting polymer plus dopants on an ITO cathode and an inkjet-printed PEDOT:PSS transparent top anode. A fully transparent blue OLEC is able to obtain light intensity > 2500 cd/m2 under pulsed driving mode and maintain stable after 1000 cycles, which fulfils requirements for simple fluorescent on-chip sensing applications. However, because of the large refractive index difference between substrates and air, about 80% of emitted light is trapped inside the device. Therefore, inkjet printed micro-lenses on the rear side are introduced here to further increase light-emitting brightness.
Quantifying fat, oil, and grease deposit formation kinetics.
Iasmin, Mahbuba; Dean, Lisa O; Ducoste, Joel J
2016-01-01
Fat, oil, and grease (FOG) deposits formed in sanitary sewers are calcium-based saponified solids that are responsible for a significant number of nationwide sanitary sewer overflows (SSOs) across United States. In the current study, the kinetics of lab-based saponified solids were determined to understand the kinetics of FOG deposit formation in sewers for two types of fat (Canola and Beef Tallow) and two types of calcium sources (calcium chloride and calcium sulfate) under three pH (7 ± 0.5, 10 ± 0.5, and ≈14) and two temperature conditions (22 ± 0.5 and 45 ± 0.5 °C). The results of this study displayed quick reactions of a fraction of fats with calcium ions to form calcium based saponified solids. Results further showed that increased palmitic fatty acid content in source fats, the magnitude of the pH, and temperature significantly affect the FOG deposit formation and saponification rates. The experimental data of the kinetics were compared with two empirical models: a) Cotte saponification model and b) Foubert crystallization model and a mass-action based mechanistic model that included alkali driven hydrolysis of triglycerides. Results showed that the mass action based mechanistic model was able to predict changes in the rate of formation of saponified solids under the different experimental conditions compared to both empirical models. The mass-action based saponification model also revealed that the hydrolysis of Beef Tallow was slower compared to liquid Canola fat resulting in smaller quantities of saponified solids. This mechanistic saponification model, with its ability to track the saponified solids chemical precursors, may provide an initial framework to predict the spatial formation of FOG deposits in municipal sewers using system wide sewer collection modeling software. Copyright © 2015 Elsevier Ltd. All rights reserved.
Lab and Pore-Scale Study of Low Permeable Soils Diffusional Tortuosity
NASA Astrophysics Data System (ADS)
Lekhov, V.; Pozdniakov, S. P.; Denisova, L.
2016-12-01
Diffusion plays important role in contaminant spreading in low permeable units. The effective diffusion coefficient of saturated porous medium depends on this coefficient in water, porosity and structural parameter of porous space - tortuosity. Theoretical models of relationship between porosity and diffusional tortuosity are usually derived for conceptual granular models of medium filled by solid particles of simple geometry. These models usually do not represent soils with complex microstructure. The empirical models, like as Archie's law, based on the experimental electrical conductivity data are mostly useful for practical applications. Such models contain empirical parameters that should be defined experimentally for given soil type. In this work, we compared tortuosity values obtained in lab-scale diffusional experiments and pore scale diffusion simulation for the studied soil microstructure and exanimated relationship between tortuosity and porosity. Samples for the study were taken from borehole cores of low-permeable silt-clay formation. Using the samples of 50 cm3 we performed lab scale diffusional experiments and estimated the lab-scale tortuosity. Next using these samples we studied the microstructure with X-ray microtomograph. Shooting performed on undisturbed microsamples of size 1,53 mm with a resolution ×300 (10243 vox). After binarization of each obtained 3-D structure, its spatial correlation analysis was performed. This analysis showed that the spatial correlation scale of the indicator variogram is considerably smaller than microsample length. Then there was the numerical simulation of the Laplace equation with binary coefficients for each microsamples. The total number of simulations at the finite-difference grid of 1753 cells was 3500. As a result the effective diffusion coefficient, tortuosity and porosity values were obtained for all studied microsamples. The results were analyzed in the form of graph of tortuosity versus porosity. The 6 experimental tortuosity values well agree with pore-scale simulations falling in the general pattern that shows nonlinear decreasing of tortuosity with decreasing of porosity. Fitting this graph by Archie model we found exponent value in the range between 1,8 and 2,4. This work was supported by RFBR via grant 14-05-00409.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berry, Max; Lystig, Ted; Beard, Jonathan
Purpose. To compare the learning of endovascular interventional skills by training on pig models versus virtual reality simulators. Methods. Twelve endovascular novices participated in a study consisting of a pig laboratory (P-Lab) and a virtual reality laboratory (VR-Lab). Subjects were stratified by experience and randomized into four training groups. Following 1 hr of didactic instruction, all attempted an iliac artery stenosis (IAS) revascularization in both laboratories. Onsite proctors evaluated performances using task-specific checklists and global rating scales, yielding a Total Score. Participants completed two training sessions of 3 hr each, using their group's assigned method (P-Lab x 2, P-Lab +more » VR-Lab, VR-Lab + P-Lab, or VR-Lab x 2) and were re-evaluated in both laboratories. A panel of two highly experienced interventional radiologists performed assessments from video recordings. ANCOVA analysis of Total Score against years of surgical, interventional radiology (IR) experience and cumulative number of P-Lab or VR-Lab sessions was conducted. Inter-rater reliability (IRR) was determined by comparing proctored scores with the video assessors in only the VR-Lab. Results. VR-Lab sessions improved the VR-Lab Total Score ({beta} 3.029, p = 0.0015) and P-Lab Total Score ({beta} = 1.814, p = 0.0452). P-Lab sessions increased the P-Lab Total Score ({beta} = 4.074, p < 0.0001) but had no effect on the VR-Lab Total Score. In the general statistical model, both P-Lab sessions ({beta} = 2.552, p = 0.0010) and VR-Lab sessions ({beta} 2.435, p = 0.0032) significantly improved Total Score. Neither previous surgical experience nor IR experience predicted Total Score. VR-Lab scores were consistently higher than the P-Lab scores ({delta} = 6.659, p < 0.0001). VR-Lab IRR was substantial (r = 0.649, p < 0.0008). Conclusions. Endovascular skills learned in the virtual environment may be transferable to the real catheterization laboratory as modeled in the P-Lab.« less
Di Gianfilippo, Martina; Hyks, Jiri; Verginelli, Iason; Costa, Giulia; Hjelmar, Ole; Lombardi, Francesco
2018-03-01
Several types of standardized laboratory leaching tests have been developed during the past few decades to evaluate the leaching behaviour of waste materials as a function of different parameters, such as the pH of the eluate and the liquid to solid ratio. However, the link between the results of these tests and leaching data collected from the field (e.g. in disposal or reuse scenarios) is not always straightforward. In this work, we compare data obtained from an on-going large scale field trial, in which municipal solid waste incineration bottom ash is being tested as road sub-base material, with the results obtained from percolation column and pH-dependence laboratory leaching tests carried out on the bottom ash at the beginning of the test. The comparisons reported in this paper show that for soluble substances (e.g. Cl, K and SO 4 ), percolation column tests can provide a good indication of the release expected in the field with deviations usually within a factor of 3. For metals characterized by a solubility-controlled release, i.e. that depends more on eluate pH than the liquid to solid ratio applied, the results of pH-dependence tests describe more accurately the eluate concentration trends observed in the field with deviations that in most cases (around 80%) are within one order of magnitude (see e.g. Al and Cd). The differences between field and lab-scale data might be in part ascribed to the occurrence in the field of weathering reactions (e.g. carbonation) but also to microbial decomposition of organic matter that modifying leachate pH affect the solubility of several constituents (e.g. Ca, Ba and Cr). Besides, weathering reactions can result in enhanced adsorption of fulvic acids to iron/aluminum (hydr)oxides, leading to a decrease in the leaching of fulvic acids and hence of elements such as Cu, Ni and Pb that strongly depend on DOC leaching. Overall, this comparison shows that percolation column tests and pH-dependence tests can represent a reliable screening tool to derive data that could be employed in risk-based analysis or life cycle assessment (LCA) frameworks for evaluating potential environmental impacts deriving from specific disposal/reuse options for waste materials. Copyright © 2017 Elsevier Ltd. All rights reserved.
Design of Force Sensor Leg for a Rocket Thrust Detector
NASA Astrophysics Data System (ADS)
Woten, Douglas; McGehee, Tripp; Wright, Anne
2005-03-01
A hybrid rocket is composed of a solid fuel and a separate liquid or gaseous oxidizer. These rockets may be throttled like liquid rockets, are safer than solid rockets, and are much less complex than liquid rockets. However, hybrid rockets produce thrust oscillations that are not practical for large scale use. A lab scale hybrid rocket at the University of Arkansas at Little Rock (UALR) Hybrid Rocket Facility is used to develop sensors to measure physical properties of hybrid rockets. Research is currently being conducted to design a six degree of freedom force sensor to measure the thrust and torque in all three spacial dimensions. The detector design uses six force sensor legs. Each leg utilizes strain gauges and a Wheatstone bridge to produce a voltage propotional to the force on the leg. The leg was designed using the CAD software ProEngineer and ProMechanica. Computer models of the strains on the single leg will be presented. A prototype leg was built and was tested in an INSTRON and results will be presented.
de Castro, Aline Machado; Carvalho, Daniele Fernandes; Freire, Denise Maria Guimarães; Castilho, Leda dos Reis
2010-01-01
Amylases are one of the most important industrial enzymes produced worldwide, with their major application being in ethanol manufacturing. This work investigated the production of amylases by solid-state fermentation of babassu cake, using the filamentous fungus Aspergillus awamori IOC-3914. Lab-scale experiments were carried out to generate input data for simulations of an industrial plant for amylase production. Additionally to the target enzymes, other hydrolases (cellulases, xylanases, and proteases) were also produced, enriching the final product. The most suitable fermentation time was 144 hours, when exoamylase and endoamylase activities of 40.5 and 42.7 U g−1 were achieved, respectively. A first evaluation showed a large impact of the inoculum propagation medium on production costs. Therefore, five propagation media were compared, and PDA medium presented the best cost-benefit ratio. The credits obtained from sales of fermented cake as a coproduct enabled a significant decrease in the production cost of the enzyme product, down to 10.40 USD kg−1. PMID:21048867
Neutron Reflectivity as a Tool for Physics-Based Studies of Model Bacterial Membranes.
Barker, Robert D; McKinley, Laura E; Titmuss, Simon
2016-01-01
The principles of neutron reflectivity and its application as a tool to provide structural information at the (sub-) molecular unit length scale from models for bacterial membranes are described. The model membranes can take the form of a monolayer for a single leaflet spread at the air/water interface, or bilayers of increasing complexity at the solid/liquid interface. Solid-supported bilayers constrain the bilayer to 2D but can be used to characterize interactions with antimicrobial peptides and benchmark high throughput lab-based techniques. Floating bilayers allow for membrane fluctuations, making the phase behaviour more representative of native membranes. Bilayers of varying levels of compositional accuracy can now be constructed, facilitating studies with aims that range from characterizing the fundamental physical interactions, through to the characterization of accurate mimetics for the inner and outer membranes of Gram-negative bacteria. Studies of the interactions of antimicrobial peptides with monolayer and bilayer models for the inner and outer membranes have revealed information about the molecular control of the outer membrane permeability, and the mode of interaction of antimicrobials with both inner and outer membranes.
Kinetic study on the effect of temperature on biogas production using a lab scale batch reactor.
Deepanraj, B; Sivasubramanian, V; Jayaraj, S
2015-11-01
In the present study, biogas production from food waste through anaerobic digestion was carried out in a 2l laboratory-scale batch reactor operating at different temperatures with a hydraulic retention time of 30 days. The reactors were operated with a solid concentration of 7.5% of total solids and pH 7. The food wastes used in this experiment were subjected to characterization studies before and after digestion. Modified Gompertz model and Logistic model were used for kinetic study of biogas production. The kinetic parameters, biogas yield potential of the substrate (B), the maximum biogas production rate (Rb) and the duration of lag phase (λ), coefficient of determination (R(2)) and root mean square error (RMSE) were estimated in each case. The effect of temperature on biogas production was evaluated experimentally and compared with the results of kinetic study. The results demonstrated that the reactor with operating temperature of 50°C achieved maximum cumulative biogas production of 7556ml with better biodegradation efficiency. Copyright © 2015 Elsevier Inc. All rights reserved.
Evolution of microorganisms in thermophilic-dry anaerobic digestion.
Montero, B; Garcia-Morales, J L; Sales, D; Solera, R
2008-05-01
Microbial population dynamics were studied during the start-up and stabilization periods in thermophilic-dry anaerobic digestion at lab-scale. The experimental protocol was defined to quantify Eubacteria and Archaea using Fluorescent in situ hybridization (FISH) in a continuously stirred tank reactor (CSTR), without recycling solids. The reactor was subjected to a programme of steady-state operation over a range of the retention times from 40 to 25 days, with an organic loading rate between 4.42 and 7.50 kg volatile solid/m3/day. Changes in microbial concentrations were linked to traditional performance parameters such as biogas production and VS removal. The relations of Eubacteria:Archaea and H2-utilising methanogens:acetate-utilising methanogens were 88:12 and 11:1, respectively, during start-up stage. Hydrogenotrophic methanogens, although important in the initial phase of the reactor start-up, were displaced by acetoclastic methanogens at steady-state, thus their relation were 7:32, respectively. The methane yield coefficient, the methane content in the biogas and VS removal were stabilized around 0.30 LCH4/gCOD, 50% and 80%, respectively. Methanogenic population correlated well with performance measurements.
2012-09-05
CAPE CANAVERAL, Fla. – Cape Canaveral Air Force Station's Solid Motor Assembly and Readiness Facility, or SMARF, Space Launch Complex 40, Space Exploration Technologies, or SpaceX, facility, and Solid Motor Assembly Building, or SMAB, are seen in the distance during a field-guided boat tour of NASA's Kennedy Space Center in Florida. As part of the center's first-ever Innovation Expo, the tour, called "Living Outdoor Laboratory for Environmental Sustainability," is giving employees the opportunity to see the unique estuarine ecosystems that are protected from development by the presence of Kennedy and the Merritt Island National Wildlife Refuge. The diverse and healthy area encompassing about 140,000 acres of central Florida's east coast has been closed to the public for 50 years, allowing the coastal dunes, saltwater estuaries and marshes, freshwater impoundments, scrub, pine flatwoods, and hardwood hammocks to provide habitats for more than 1,000 species of plants and animals. Innovation Expo is showcasing the innovative work taking place throughout the center's facilities and labs to encourage employees to work together to solve future challenges. For more information, visit http://www.nasa.gov/kennedy. Photo credit: NASA
recognized in are Accreditation of Testing Labs, Calibration Labs, Medical Labs, Inspection Bodies Testing Labs, Calibration Labs, Medical Labs, Inspection Bodies, Certification of QMS, EMS and FSMS. 4 Jul
Final Report of Tank 241-C-105 Dissolution, the Phase 2 Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meznarich, Huei K.; bolling, Stacey D.; Cooke, Gary A.
2016-10-01
Three clamshell grab samples were taken from Tank 241-C-105 in October 2015 in accordance with RPP-PLAN-60011. Analytical results of those samples were issued in the report RPP-RPT-59115 by Wastren Advantage, Inc., Hanford Laboratory. Solid phase characterization results were reported separately in LAB-RPT-15-00011 and in RPP-RPT-59147. The major solid phases reported to be present were dawsonite [NaAlCO 3(OH) 2], trona [Na 3(HCO 3)(CO 3)·2H 2O], cejkaite [Na 4(UO 2)(CO 3) 3], and an unidentified organic solid, with minor amounts of gibbsite [Al(OH) 3], natrophosphate [Na 7F(PO 4) 2·19H 2O], and traces of unidentified iron-rich and manganese-rich phases. Note that the presencemore » of dawsonite, trona, and cejkaite requires a relatively low pH, likely around pH 9 to 10. One aliquot of each grab sample was provided to 222-S Laboratory Process Chemistry for dissolution studies. Phase 1 of the dissolution testing followed the approved test plan, WRPS-1404813, Rev. 3, and examined the behavior of the Tank 241-C-105 solids treated with water, 19M sodium hydroxide, 2M nitric acid, and 0.5M oxalic acid/2M nitric acid. Phase 2 of the testing was conducted in accordance with instructions from the client and emphasized treatment with 19M sodium hydroxide followed by water washing. This is the report of the Phase 2 testing.« less
ERIC Educational Resources Information Center
Balakrishnan, B.; Woods, P. C.
2013-01-01
Over the years, rapid development in computer technology has engendered simulation-based laboratory (lab) in addition to the traditional hands-on (physical) lab. Many higher education institutions adopt simulation lab, replacing some existing physical lab experiments. The creation of new systems for conducting engineering lab activities has raised…
Quintana, José Benito; Miró, Manuel; Estela, José Manuel; Cerdà, Víctor
2006-04-15
In this paper, the third generation of flow injection analysis, also named the lab-on-valve (LOV) approach, is proposed for the first time as a front end to high-performance liquid chromatography (HPLC) for on-line solid-phase extraction (SPE) sample processing by exploiting the bead injection (BI) concept. The proposed microanalytical system based on discontinuous programmable flow features automated packing (and withdrawal after single use) of a small amount of sorbent (<5 mg) into the microconduits of the flow network and quantitative elution of sorbed species into a narrow band (150 microL of 95% MeOH). The hyphenation of multisyringe flow injection analysis (MSFIA) with BI-LOV prior to HPLC analysis is utilized for on-line postextraction treatment to ensure chemical compatibility between the eluate medium and the initial HPLC gradient conditions. This circumvents the band-broadening effect commonly observed in conventional on-line SPE-based sample processors due to the low eluting strength of the mobile phase. The potential of the novel MSFI-BI-LOV hyphenation for on-line handling of complex environmental and biological samples prior to reversed-phase chromatographic separations was assessed for the expeditious determination of five acidic pharmaceutical residues (viz., ketoprofen, naproxen, bezafibrate, diclofenac, and ibuprofen) and one metabolite (viz., salicylic acid) in surface water, urban wastewater, and urine. To this end, the copolymeric divinylbenzene-co-n-vinylpyrrolidone beads (Oasis HLB) were utilized as renewable sorptive entities in the micromachined unit. The automated analytical method features relative recovery percentages of >88%, limits of detection within the range 0.02-0.67 ng mL(-1), and coefficients of variation <11% for the column renewable mode and gives rise to a drastic reduction in operation costs ( approximately 25-fold) as compared to on-line column switching systems.
Multifunctional picoliter droplet manipulation platform and its application in single cell analysis.
Gu, Shu-Qing; Zhang, Yun-Xia; Zhu, Ying; Du, Wen-Bin; Yao, Bo; Fang, Qun
2011-10-01
We developed an automated and multifunctional microfluidic platform based on DropLab to perform flexible generation and complex manipulations of picoliter-scale droplets. Multiple manipulations including precise droplet generation, sequential reagent merging, and multistep solid-phase extraction for picoliter-scale droplets could be achieved in the present platform. The system precision in generating picoliter-scale droplets was significantly improved by minimizing the thermo-induced fluctuation of flow rate. A novel droplet fusion technique based on the difference of droplet interfacial tensions was developed without the need of special microchannel networks or external devices. It enabled sequential addition of reagents to droplets on demand for multistep reactions. We also developed an effective picoliter-scale droplet splitting technique with magnetic actuation. The difficulty in phase separation of magnetic beads from picoliter-scale droplets due to the high interfacial tension was overcome using ferromagnetic particles to carry the magnetic beads to pass through the phase interface. With this technique, multistep solid-phase extraction was achieved among picoliter-scale droplets. The present platform had the ability to perform complex multistep manipulations to picoliter-scale droplets, which is particularly required for single cell analysis. Its utility and potentials in single cell analysis were preliminarily demonstrated in achieving high-efficiency single-cell encapsulation, enzyme activity assay at the single cell level, and especially, single cell DNA purification based on solid-phase extraction.
Meullemiestre, A; Petitcolas, E; Maache-Rezzoug, Z; Chemat, F; Rezzoug, S A
2016-01-01
Maritime pine sawdust, a by-product from industry of wood transformation, has been investigated as a potential source of polyphenols which were extracted by ultrasound-assisted maceration (UAM). UAM was optimized for enhancing extraction efficiency of polyphenols and reducing time-consuming. In a first time, a preliminary study was carried out to optimize the solid/liquid ratio (6g of dry material per mL) and the particle size (0.26 cm(2)) by conventional maceration (CVM). Under these conditions, the optimum conditions for polyphenols extraction by UAM, obtained by response surface methodology, were 0.67 W/cm(2) for the ultrasonic intensity (UI), 40°C for the processing temperature (T) and 43 min for the sonication time (t). UAM was compared with CVM, the results showed that the quantity of polyphenols was improved by 40% (342.4 and 233.5mg of catechin equivalent per 100g of dry basis, respectively for UAM and CVM). A multistage cross-current extraction procedure allowed evaluating the real impact of UAM on the solid-liquid extraction enhancement. The potential industrialization of this procedure was implemented through a transition from a lab sonicated reactor (3 L) to a large scale one with 30 L volume. Copyright © 2015 Elsevier B.V. All rights reserved.
An optimized prototype of electromagnetic calorimeter for the SoLID project at Jefferson Lab
NASA Astrophysics Data System (ADS)
Shen, C.; Wang, Y.; Xiao, D.; Han, D.; Zou, Z.; Li, Y.; Zheng, X.; Chen, J.
2018-02-01
A shashlik-type electromagnetic calorimeter will be produced in Hall A of Jefferson Laboratory for the Solenoidal Large Intensity Device (SoLID). Wavelength-shifting (WLS) fibers and clear fibers will be used as the light guide part of the calorimeter. The blue light from scintillators is converted into green light by WLS fibers and is carried out to the back of the calorimeters for readout. Since the magnetic field of SoLID reaches about 1.5 T behind the calorimeters, the design is to use clear fibers to further guide the light out of the solenoid for readout by PMTs. Therefore, it is important to study the perfomance of WLS and clear fibers. This paper describes a comparative test of two different WLS fibers and a light attenuation test for a clear fiber. The results show that the performance of the two WLS fibers is the same under large curvature bending, and that the bending has no effect on the light transmission through the clear fiber. In addition, a comparison test for two fiber end-face reflective materials is also reported. It reveals that the use of silver ink as a reflective material can increase the light yield by 30%. Thereby, an optimized prototype based on the above experimental results was built and the basic performance was tested.
Soria, J; Gauthier, D; Falcoz, Q; Flamant, G; Mazza, G
2013-03-15
The emissions of heavy metals during incineration of Municipal Solid Waste (MSW) are a major issue to health and the environment. It is then necessary to well quantify these emissions in order to accomplish an adequate control and prevent the heavy metals from leaving the stacks. In this study the kinetic behavior of Cadmium during Fluidized Bed Incineration (FBI) of artificial MSW pellets, for bed temperatures ranging from 923 to 1073 K, was modeled. FLUENT 12.1.4 was used as the modeling framework for the simulations and implemented together with a complete set of user-defined functions (UDFs). The CFD model combines the combustion of a single solid waste particle with heavy metal (HM) vaporization from the burning particle, and it takes also into account both pyrolysis and volatiles' combustion. A kinetic rate law for the Cd release, derived from the CFD thermal analysis of the combusting particle, is proposed. The simulation results are compared with experimental data obtained in a lab-scale fluidized bed incinerator reported in literature, and with the predicted values from a particulate non-isothermal model, formerly developed by the authors. The comparison shows that the proposed CFD model represents very well the evolution of the HM release for the considered range of bed temperature. Copyright © 2013 Elsevier B.V. All rights reserved.
Shi, Ao
2016-02-01
A method has been developed for the simultaneous determination of 23 antibiotics (four categories) and 3 β-agonists in livestock drinking water using solid-phase extraction and ultra performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (UPLC-ESI MS/MS). The samples were adjusted pH to 5. 0, added Na2EDTA, enriched and cleaned-up by an HLB solid-phase extraction cartridge. The target compounds were confirmed and quantified by UPLC-ESI MS/MS with external standard method for the anti- biotics and internal standard method for the β-agonists. The recoveries were assessed by using lab tap water as matrix. The average recoveries of the 23 antibiotics and the 3 β-agonists were in the range of 50. 7%-104. 6% and the relative standard deviations (RSDs) were 2. 6%-8. 8% (n= 3). Under the optimal conditions, the calibration curves of the 23 antibiotics and the 3 β-agonists showed good linearity with the correlation coefficients better than 0. 994. The limits of detection (LODs, S/N≥3) ranged from 0. 01-0. 20 ng/L. The developed method was applied to analyze the livestock drinking waters in 36 Beijing intensive livestock farms. The results showed that some antibiotics were detected.
NASA Astrophysics Data System (ADS)
Lu, Qiang; Zhang, Zhen-xi; Wang, Xin; Guo, Hao-qiang; Cui, Min-shu; Yang, Yong-ping
2018-02-01
A new technique was proposed to co-produce phenol and activated carbon (AC) from catalytic fast pyrolysis of biomass impregnated with K3PO4 in a hydrogen atmosphere, followed by activation of the pyrolytic solid residues. Lab-scale catalytic fast pyrolysis experiments were performed to quantitatively determine the pyrolytic product distribution, as well as to investigate the effects of several factors on the phenol production, including pyrolysis atmosphere, catalyst type, biomass type, catalytic pyrolysis temperature, and catalyst impregnation content. In addition, the pyrolytic solid residues were activated to prepare ACs with high specific surface areas. The results indicated that phenol could be obtained due to the synergistic effects of K3PO4 and hydrogen atmosphere, with the yield and selectivity reaching 5.3 wt% and 17.8% from catalytic fast pyrolysis of poplar wood with 8 wt% K3PO4 at 550 oC in a hydrogen atmosphere. This technique was adaptable to different woody materials for phenol production. Moreover, gas product generated from the pyrolysis process was feasible to be recycled to provide the hydrogen atmosphere, instead of extra hydrogen supply. In addition, the pyrolytic solid residue was suitable for AC preparation, using CO2 activation method, the specific surface area was as high as 1605 m2/g.
Lu, Qiang; Zhang, Zhen-xi; Wang, Xin; Guo, Hao-qiang; Cui, Min-shu; Yang, Yong-ping
2018-01-01
A new technique was proposed to co-produce phenol and activated carbon (AC) from catalytic fast pyrolysis of biomass impregnated with K3PO4 in a hydrogen atmosphere, followed by activation of the pyrolytic solid residues. Lab-scale catalytic fast pyrolysis experiments were performed to quantitatively determine the pyrolytic product distribution, as well as to investigate the effects of several factors on the phenol production, including pyrolysis atmosphere, catalyst type, biomass type, catalytic pyrolysis temperature, and catalyst impregnation content. In addition, the pyrolytic solid residues were activated to prepare ACs with high specific surface areas. The results indicated that phenol could be obtained due to the synergistic effects of K3PO4 and hydrogen atmosphere, with the yield and selectivity reaching 5.3 wt% and 17.8% from catalytic fast pyrolysis of poplar wood with 8 wt% K3PO4 at 550°C in a hydrogen atmosphere. This technique was adaptable to different woody materials for phenol production. Moreover, gas product generated from the pyrolysis process was feasible to be recycled to provide the hydrogen atmosphere, instead of extra hydrogen supply. In addition, the pyrolytic solid residue was suitable for AC preparation, using CO2 activation method, the specific surface area was as high as 1,605 m2/g. PMID:29515994
Lu, Qiang; Zhang, Zhen-Xi; Wang, Xin; Guo, Hao-Qiang; Cui, Min-Shu; Yang, Yong-Ping
2018-01-01
A new technique was proposed to co-produce phenol and activated carbon (AC) from catalytic fast pyrolysis of biomass impregnated with K 3 PO 4 in a hydrogen atmosphere, followed by activation of the pyrolytic solid residues. Lab-scale catalytic fast pyrolysis experiments were performed to quantitatively determine the pyrolytic product distribution, as well as to investigate the effects of several factors on the phenol production, including pyrolysis atmosphere, catalyst type, biomass type, catalytic pyrolysis temperature, and catalyst impregnation content. In addition, the pyrolytic solid residues were activated to prepare ACs with high specific surface areas. The results indicated that phenol could be obtained due to the synergistic effects of K 3 PO 4 and hydrogen atmosphere, with the yield and selectivity reaching 5.3 wt% and 17.8% from catalytic fast pyrolysis of poplar wood with 8 wt% K 3 PO 4 at 550°C in a hydrogen atmosphere. This technique was adaptable to different woody materials for phenol production. Moreover, gas product generated from the pyrolysis process was feasible to be recycled to provide the hydrogen atmosphere, instead of extra hydrogen supply. In addition, the pyrolytic solid residue was suitable for AC preparation, using CO 2 activation method, the specific surface area was as high as 1,605 m 2 /g.
A tunable optofluidic circular liquid fiber
NASA Astrophysics Data System (ADS)
Li, Lei; Wu, Wei; Shi, Yang; Gong, Enze; Yang, Yi
2016-01-01
This paper presents a tunable optofluidic circular liquid fiber through the numerical simulation. Fiber is a significant optical device and has been widely applied on optical fiber communication. But the fiber based solid has limited tunability. Compared to solid fiber, the fiber based liquid material is relatively infrequent. Cause for the liquid optical device has more freedom tunable properties than solid counterpart, it has attracted more interest. The traditional optofluidic waveguide is designed like a sandwich in planar channel. This two-dimensional (2D) structure liquid waveguide will face huge transmission loss in the perpendicular direction of the flow streams. In this paper, a curving microchannel is designed inside the microchip to produce centrifugal effect. Two different liquids are injected into the chip by external pumps. In a particular situation, the core flow will be totally surrounded by the cladding flow. So the liquid can form an optical waveguide. Its structure is similar to an optical fiber which high refractive index (RI) liquid is core of the waveguide and the low RI liquid is cladding of the waveguide. Profit from the reconfigurability of liquid material, this liquid fiber has excellent tunability. The diameter of the core flow can be tuned in a wider range by changing the volume ratio of the flows through the finite element analysis. It is predictable that such a tunable liquid fiber may find wider applications in lab-on-a-chip systems and integrated optical devices.
Siciliano, Alessio; De Rosa, Salvatore
2016-08-01
In this study, the performance of a lab-scale Moving Bed Biofilm Reactor (MBBR) under different operating conditions was analysed. Moreover, the dependence of the reaction rates both from the concentration and biodegradability of substrates and from the biofilm surface density, by means of several batch kinetic tests, was investigated. The reactor controls exhibited an increasing COD (Chemical Oxygen Demand) removal, reaching maximum yields (close to 90%) for influent loadings of up to12.5 gCOD/m(2)d. From this value, the pilot plant performance decreased to yields of only about 55% for influent loadings greater than 16 gCOD/m(2)d. In response to the influent loading increase, the biofilm surface density exhibited a logistic growing trend until reaching a maximum amount of total attached solids of about 9.5 g/m(2). The kinetic test results indicated that the COD removal rates for rapidly biodegradable, rapidly hydrolysable and slowly biodegradable substrates were not affected by the organic matter concentrations. Instead, first-order kinetics were detected with respect to biofilm surface density. The experimental results permitted the formulation of a mathematical model to predict the MBBR organic matter removal efficiency. The validity of the model was successfully tested in the lab-scale plant.
Random lasers for lab-on-chip applications
NASA Astrophysics Data System (ADS)
Giehl, J. M.; Butzbach, F.; Jorge, K. C.; Alvarado, M. A.; Carreño, M. N. P.; Alayo, M. I.; Wetter, N. U.
2016-04-01
Random lasers are laser sources in which the feedback is provided by scattering instead of reflection and which, for this reason, do not require surfaces with optical finish such as mirrors. The investigation of such lasing action in a large variety of disordered materials is a subject of high interest with very important applications such as threedimensional and speckle-free imaging, detection of cancer tissue and photonic coding and encryption. However, potential applications require optimization of random laser performance especially with respect to optical efficiency and directionality or brightness. This work demonstrates such an optimization procedure with the goal of achieving a random laser with sufficient efficiency and brightness in order to be used in practical applications. Two random lasers are demonstrated, one solid and on liquid, that fulfil directionality and efficiency requirements. The first one consists of a neodymium doped powder laser with a record slope efficiency of 1.6%. The second one is a liquid random laser injected into a HC-ARROW waveguide which uses a microchannel connected to a much larger reservoir in order to achieve the necessary directionality. Both devices can be produced by low cost fabricating technologies and easily integrated into next-generation, lab-on-chip devices used for in-situ determination of infectious tropical diseases, which is the main goal of this project.
CPMC-Lab: A MATLAB package for Constrained Path Monte Carlo calculations
NASA Astrophysics Data System (ADS)
Nguyen, Huy; Shi, Hao; Xu, Jie; Zhang, Shiwei
2014-12-01
We describe CPMC-Lab, a MATLAB program for the constrained-path and phaseless auxiliary-field Monte Carlo methods. These methods have allowed applications ranging from the study of strongly correlated models, such as the Hubbard model, to ab initio calculations in molecules and solids. The present package implements the full ground-state constrained-path Monte Carlo (CPMC) method in MATLAB with a graphical interface, using the Hubbard model as an example. The package can perform calculations in finite supercells in any dimensions, under periodic or twist boundary conditions. Importance sampling and all other algorithmic details of a total energy calculation are included and illustrated. This open-source tool allows users to experiment with various model and run parameters and visualize the results. It provides a direct and interactive environment to learn the method and study the code with minimal overhead for setup. Furthermore, the package can be easily generalized for auxiliary-field quantum Monte Carlo (AFQMC) calculations in many other models for correlated electron systems, and can serve as a template for developing a production code for AFQMC total energy calculations in real materials. Several illustrative studies are carried out in one- and two-dimensional lattices on total energy, kinetic energy, potential energy, and charge- and spin-gaps.
Huang, Camillan
2003-01-01
Technology has created a new dimension for visual teaching and learning with web-delivered interactive media. The Virtual Labs Project has embraced this technology with instructional design and evaluation methodologies behind the simPHYSIO suite of simulation-based, online interactive teaching modules in physiology for the Stanford students. In addition, simPHYSIO provides the convenience of anytime web-access and a modular structure that allows for personalization and customization of the learning material. This innovative tool provides a solid delivery and pedagogical backbone that can be applied to developing an interactive simulation-based training tool for the use and management of the Picture Archiving and Communication System (PACS) image information system. The disparity in the knowledge between health and IT professionals can be bridged by providing convenient modular teaching tools to fill the gaps in knowledge. An innovative teaching method in the whole PACS is deemed necessary for its successful implementation and operation since it has become widely distributed with many interfaces, components, and customizations. This paper will discuss the techniques for developing an interactive-based teaching tool, a case study of its implementation, and a perspective for applying this approach to an online PACS training tool. Copyright 2002 Elsevier Science Ltd.
4D nano-tomography of electrochemical energy devices using lab-based X-ray imaging
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heenan, T. M. M.; Finegan, D. P.; Tjaden, B.
Electrochemical energy devices offer a variety of alternate means for low-carbon, multi-scale energy conversion and storage. Reactions in these devices are supported by electrodes with characteristically complex microstructures. To meet the increasing capacity and lifetime demands across a range of applications, it is essential to understand microstructural evolutions at a cell and electrode level which are thought to be critical aspects influencing material and device lifetime and performance. X-ray computed tomography (CT) has become a highly employed method for non-destructive characterisation of such microstructures with high spatial resolution. However, sub-micron resolutions present significant challenges for sample preparation and handling particularlymore » in 4D studies, (three spatial dimensions plus time). Here, microstructural information is collected from the same region of interest within two electrode materials: a solid oxide fuel cell and the positive electrode from a lithium-ion battery. Using a lab-based X-ray instrument, tomograms with sub-micron resolutions were obtained between thermal cycling. The intricate microstructural evolutions captured within these two materials provide model examples of 4D X-ray nano-CT capabilities in tracking challenging degradation mechanisms. This technique is valuable in the advancement of electrochemical research as well as broader applications for materials characterisation.« less
NASA Astrophysics Data System (ADS)
Hule, Rohan; Thurman, Derek; Doufas, Antonios
Polyolefins occupy a significant volume of the polymer products portfolio in commodity and high value applications. Quantifying and optimizing structure-property relationships enables growth in new markets. It is well recognized that coupling lab-based, comprehensive methodologies with bulk properties of interest to industrial environments offer the greatest potential of technology advancement, ultimately leading to commercial success. It is imperative to recognize the existing gap of knowledge translation between lab measurements and industrial-scale operability. This study highlights experimental HDPEs synthesized from dual, single-site, co-supported catalysts that exhibit enhanced solid-state properties such as stiffness, impact and ESCR surpassing conventional trends. Commercial resins across distinct sub-families were included as well. Commonality amongst these resins is bimodality and broad MW distribution with well-defined splits and spreads. Investigations on commercially relevant parameters such as melt strength, melt elasticity and shear thinning established excellent performance for experimental bimodals, corroborating potential benefits compared to commercial HDPEs. To summarize, the effort highlights well-recognized pathways such as improvements in mechanical and melt properties that can be attributed to apposite tuning of polymer chain architecture and MW distribution with implications across myriad markets. Ultimately, this may serve as a pathway for producing innovative products that deliver business success and growth.
Garofalo, C; Silvestri, G; Aquilanti, L; Clementi, F
2008-07-01
To study lactic acid bacteria (LAB) and yeast dynamics during the production processes of sweet-leavened goods manufactured with type I sourdoughs. Fourteen sourdough and dough samples were taken from a baking company in central Italy during the production lines of three varieties of Panettone. The samples underwent pH measurements and plating analysis on three solid media. The microbial DNA was extracted from both the (sour)doughs and the viable LAB and yeast cells collected in bulk, and subjected to PCR-denaturing gradient gel electrophoresis (DGGE) analysis. The molecular fingerprinting of the cultivable plus noncultivable microbial populations provide evidence of the dominance of Lactobacillus sanfranciscensis, Lactobacillus brevis and Candida humilis in the three fermentation processes. The DGGE profiles of the cultivable communities reveal a bacterial shift in the final stages of two of the production processes, suggesting an effect of technological parameters on the selection of the dough microflora. Our findings confirm the importance of using a combined analytical approach to explore microbial communities that develop during the leavening process of sweet-leavened goods. In-depth studies of sourdough biodiversity and population dynamics occurring during sourdough fermentation are fundamental for the control of the leavening process and the manufacture of standardized, high-quality products.
An observational study of the effect of vibration on the caking of suspensions in oily vehicles.
Jain, Rohit; Bork, Olaf; Alawi, Fadil; Nanjan, Karthigeyan; Tucker, Ian G
2016-11-30
An oily suspension of penethamate (PNT) that was physically stable on storage, caked solidly during road/air transport. This paper reports on the caking behaviour of PNT oily suspension formulations exposed to vibrations in a lab-based test designed to simulate road/air transport. The lab-test was used to study the effects of container type (glass v PET) and formulation (oil, surfactant type and concentration) on the physical stability of suspension under vibration. Redispersibility of the sediment was lower at longer vibrations times and at higher intensity of vibration. Caking on vibration was strongly influenced by the type of container (caking in glass but not in PET) possibly due to tribo-charging of particles. Caking on vibration was dependent on the formulation: type and concentration of surfactant; type of oil. The physical stability of oily suspensions, and the effect of vibration are two areas which have been largely neglected in the pharmaceutical literature. This paper discusses some potential mechanisms for the observations but studies using fully characterised materials are required. Finally we conclude that static testing of physical stability of oily suspensions is not sufficient and that a vibrational stress test is required. Copyright © 2016 Elsevier B.V. All rights reserved.
Engineering-Scale Demonstration of DuraLith and Ceramicrete Waste Forms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Josephson, Gary B.; Westsik, Joseph H.; Pires, Richard P.
2011-09-23
To support the selection of a waste form for the liquid secondary wastes from the Hanford Waste Immobilization and Treatment Plant, Washington River Protection Solutions (WRPS) has initiated secondary waste form testing on four candidate waste forms. Two of the candidate waste forms have not been developed to scale as the more mature waste forms. This work describes engineering-scale demonstrations conducted on Ceramicrete and DuraLith candidate waste forms. Both candidate waste forms were successfully demonstrated at an engineering scale. A preliminary conceptual design could be prepared for full-scale production of the candidate waste forms. However, both waste forms are stillmore » too immature to support a detailed design. Formulations for each candidate waste form need to be developed so that the material has a longer working time after mixing the liquid and solid constituents together. Formulations optimized based on previous lab studies did not have sufficient working time to support large-scale testing. The engineering-scale testing was successfully completed using modified formulations. Further lab development and parametric studies are needed to optimize formulations with adequate working time and assess the effects of changes in raw materials and process parameters on the final product performance. Studies on effects of mixing intensity on the initial set time of the waste forms are also needed.« less
Pinloche, E; Williams, M; D'Inca, R; Auclair, E; Newbold, C J
2012-12-01
The impact of 2 doses of a Saccharomyces cerevisiae were evaluated, 5 × 10(10) cfu/kg of feed (L1) and 5 × 10(11) cfu/kg of feed (L2) against a control (CON) with no added yeast, using an in vitro model [colon simulation technique (Cositec)] to mimic digestion in the pig colon. The L2 (but not L1) dose significantly improved DM digestibility compared to CON (61 v 58%) and increased NH(3) concentrations (+15%). Volatile fatty acid concentrations increased with L2 compared to CON--isobutyrate (+13.5%), propionate (+8.5%), isovalerate (+17.8%), and valerate (+25%)--but only valerate was increased with L1 (+14.2%). The analysis of microbiota from the liquid associated bacteria (LAB) and solid associated bacteria (SAB) revealed an interaction between the fraction and treatment (P < 0.05). Indeed, L2 had a significant impact on SAB and LAB (P < 0.01) whereas L1 only tended to change the structure of the population in the SAB (P < 0.1). Overall, this study showed that a live yeast probiotic could improve digestion in a colonic simulation model but only at the higher dose used and this effect was associated with a shift in the bacterial population therein.
Bacterial community structure of a lab-scale anammox membrane bioreactor.
Gonzalez-Martinez, Alejandro; Osorio, F; Rodriguez-Sanchez, Alejandro; Martinez-Toledo, Maria Victoria; Gonzalez-Lopez, Jesus; Lotti, Tommaso; van Loosdrecht, M C M
2015-01-01
Autotrophic nitrogen removal technologies have proliferated through the last decade. Among these, a promising one is the membrane bioreactor (MBR) Anammox, which can achieve very high solids retention time and therefore sets a proper environment for the cultivation of anammox bacteria. In this sense, the MBR Anammox is an efficient technology for the treatment of effluents with low organic carbon and high ammonium concentrations once it has been treated under partial nitrification systems. A lab-scale MBR Anammox bioreactor has been built at the Technological University of Delft, The Netherlands and has been proven for efficient nitrogen removal and efficient cultivation of anammox bacteria. In this study, next-generation sequencing techniques have been used for the investigation of the bacterial communities of this MBR Anammox for the first time ever. A strong domination of Candidatus Brocadia bacterium and also the presence of a myriad of other microorganisms that have adapted to this environment were detected, suggesting that the MBR Anammox bioreactor might have a more complex microbial ecosystem that it has been thought. Among these, nitrate-reducing heterotrophs and primary producers, among others, were identified. Definition of the ecological roles of the OTUs identified through metagenomic analysis was discussed. © 2014 American Institute of Chemical Engineers.
Comparison of Methods to Determine Algal Concentrations in Freshwater Lakes
NASA Astrophysics Data System (ADS)
Georgian, S. E.; Halfman, J. D.
2008-12-01
Algal populations are extremely important to the ecological health of freshwater lake systems. As lakes become eutrophic (highly productive) through nutrient loading, sediment accumulation rates increase, bottom waters become anoxic in the mid-to late summer, the opacity of the water column decreases, and significantly decreases the lake's potential as a drinking water source and places respiratory stress on aquatic animals. One indicator of eutrophication is increasing algal concentrations over annual time frames. Algal concentrations can be measured by the concentration of chlorophyll a, or less directly by fluorescence, secchi disk depth, and turbidity by backscattering and total suspended solids. Here, we present a comparison of these methods using data collected on Honeoye, Canandaigua, Keuka, Seneca, Cayuga, Owasco, Skaneateles, and Otisco, the largest Finger Lakes of western and central New York State during the 2008 field season. A total of 124 samples were collected from at least two mid-lake, deep-water sites in each lake monthly through the 2008 field season (May-Oct); Seneca Lake was sampled weekly at four sites and Cayuga Lake every two weeks at six sites. Secchi depths, CTD profiles and surface water samples were collected at each site. Chlorophyll a was measured by spectrophotometer in the lab after filtration at 0.45 um and digestion of the residue in acetone. Water samples were also filtered through pre-weighed glass-fiber filters for total suspended solids concentrations. A SBE-25 SeaLogger CTD collected profiles of turbidity and fluorescence with WetLabs ECO FL-NTU. Surface CTD values were used in the comparison. The strongest linear correlations were detected between chlorophyll-a and fluorescence (r2 = 0.65), and total suspended solids and turbidity (r2 = 0.63). Weaker correlations were detected between secchi depths and chlorophyll-a (r2 = 0.42), and secchi depths and turbidity (r2 = 0.46). The weakest correlations were detected between secchi depths and fluorescence (r2 = 0.29), total suspended solids and fluorescence (r2 = 0.29), chlorophyll-a and turbidity (r2 = 0.34) and fluorescence and turbidity (r2 = 0.25). The results suggest that water clarity in these lakes was controlled by both inorganic and organic (algal) suspended matter, and each method typically focuses on either the organic or inorganic fractions of the total suspended sediment population. Interestingly, fluorescence profiles revealed algal peaks at depth in the epilimnion and occasionally in the upper hypolimnion of these lakes. The peak in fluorescence was shallower in algal-rich lakes. Thus, lake monitoring protocols and assessments should include all of these parameters to adequately quantify the type and concentration of suspended matter, and expand from surface samples to integrate the entire water column.
Design of inquiry-oriented science labs: impacts on students' attitudes
NASA Astrophysics Data System (ADS)
Baseya, J. M.; Francis, C. D.
2011-11-01
Background: Changes in lab style can lead to differences in learning. Two inquiry-oriented lab styles are guided inquiry (GI) and problem-based (PB). Students' attitudes towards lab are important to consider when choosing between GI and PB styles during curriculum design. Purpose: We examined the degree to which lab experiences are explained by a GI or a PB lab style vs. students' attitudes towards specific aspects of the experience, reflected by perceived excitement (exc), difficulty (dif), time efficiency (eff) and association between lab and lecture material (help). Sample: Approximately 1000 students attending first-semester, college biology lab for science majors at the University of Colorado at Boulder, USA, participated in the study. Design and method: In 2007, two labs were run as GI and one as PB. Formats were switched in 2008. Attitudes were assessed with a post-semester survey. Results: Only the four attitude variables (not lab style) had a strong relationship with overall lab rating which was most strongly related to exc, followed by dif and help/eff. Dif and eff had the greatest influence on attitudes for or against GI vs. PB labs, and help and exc had little influence on a GI vs. a PB lab. Also, when dif was low, students' attitudes were not significantly different between PB and GI labs, but when dif was high, students' significantly rated GI labs higher than PB labs. Conclusions: Students' attitudes towards lab are more dependent on specific aspects of the experience than on lab style. Changes in GI vs. PB lab styles primarily influence dif and eff rather than exc and help. Dif may be an important factor to consider when implementing a lab in the PB vs. the GI format. It might be good to go with a GI when dif is high and a PB when dif is low.
Awakening interest in the natural sciences - BASF's Kids' Labs.
Lang, Cinthia
2012-01-01
At BASF's Ludwigshafen headquarters, kids and young adults in grades 1-13 can learn about chemistry in the Kids' Labs. Different programs exist for different levels of knowledge. In the two 'Hands-on Lab H(2)O & Co.' Kids' Labs, students from grades 1-6 explore the secrets of chemistry. BASF Kids' Labs have now been set up in over 30 countries. In Switzerland alone, almost 2,000 students have taken part in the 'Water Loves Chemistry' Kids' Lab since it was started in 2011. In Alsace, 600 students have participated to date. In the Teens' Lab 'Xplore Middle School', middle school students explore five different programs with the themes 'substance labyrinth', 'nutrition', 'coffee, caffeine & co.', 'cosmetics' and 'energy'. Biotechnological methods are the focus of the Teens' Lab 'Xplore Biotech' for students taking basic and advanced biology courses. In the 'Xplore High School' Teens' Lab, chemistry teachers present their own experimental lab instruction for students in basic and advanced chemistry courses. The Virtual Lab has been expanding the offerings of the BASF Kids' Labs since 2011. The online lab was developed by the company for the International Year Of Chemistry and gives kids and young adults the opportunity to do interactive experiments outside of the lab.
Interactive, Online, Adsorption Lab to Support Discovery of the Scientific Process
NASA Astrophysics Data System (ADS)
Carroll, K. C.; Ulery, A. L.; Chamberlin, B.; Dettmer, A.
2014-12-01
Science students require more than methods practice in lab activities; they must gain an understanding of the application of the scientific process through lab work. Large classes, time constraints, and funding may limit student access to science labs, denying students access to the types of experiential learning needed to motivate and develop new scientists. Interactive, discovery-based computer simulations and virtual labs provide an alternative, low-risk opportunity for learners to engage in lab processes and activities. Students can conduct experiments, collect data, draw conclusions, and even abort a session. We have developed an online virtual lab, through which students can interactively develop as scientists as they learn about scientific concepts, lab equipment, and proper lab techniques. Our first lab topic is adsorption of chemicals to soil, but the methodology is transferrable to other topics. In addition to learning the specific procedures involved in each lab, the online activities will prompt exploration and practice in key scientific and mathematical concepts, such as unit conversion, significant digits, assessing risks, evaluating bias, and assessing quantity and quality of data. These labs are not designed to replace traditional lab instruction, but to supplement instruction on challenging or particularly time-consuming concepts. To complement classroom instruction, students can engage in a lab experience outside the lab and over a shorter time period than often required with real-world adsorption studies. More importantly, students can reflect, discuss, review, and even fail at their lab experience as part of the process to see why natural processes and scientific approaches work the way they do. Our Media Productions team has completed a series of online digital labs available at virtuallabs.nmsu.edu and scienceofsoil.com, and these virtual labs are being integrated into coursework to evaluate changes in student learning.
The laboratory report: A pedagogical tool in college science courses
NASA Astrophysics Data System (ADS)
Ferzli, Miriam
When viewed as a product rather than a process that aids in student learning, the lab report may become rote, busywork for both students and instructors. Students fail to see the purpose of the lab report, and instructors see them as a heavy grading load. If lab reports are taught as part of a process rather than a product that aims to "get the right answer," they may serve as pedagogical tools in college science courses. In response to these issues, an in-depth, web-based tutorial named LabWrite (www.ncsu.edu/labwrite) was developed to help students and instructors (www.ncsu.edu/labwrite/instructors) understand the purpose of the lab report as grounded in the written discourse and processes of science. The objective of this post-test only quasi-experimental study was to examine the role that in-depth instruction such as LabWrite plays in helping students to develop skills characteristic of scientifically literate individuals. Student lab reports from an introductory-level biology course at NC State University were scored for overall understanding of scientific concepts and scientific ways of thinking. The study also looked at students' attitudes toward science and lab report writing, as well as students' perceptions of lab reports in general. Significant statistical findings from this study show that students using LabWrite were able to write lab reports that showed a greater understanding of scientific investigations (p < .003) and scientific ways of thinking (p < .0001) than students receiving traditional lab report writing instruction. LabWrite also helped students develop positive attitudes toward lab reports as compared to non-LabWrite users (p < .01). Students using LabWrite seemed to perceive the lab report as a valuable tool for determining learning objectives, understanding science concepts, revisiting the lab experience, and documenting their learning.
Fuel Cell Technology Status Composite Data Products | Hydrogen and Fuel
Hours to 10% Stack Voltage Degradation CDP LAB 01, 5/8/17 Durability Lab Data Projection Sensitivity to Voltage Degradation Levels CDP LAB 02, 5/8/17 Field and Lab Durability Projection Comparison for LAB 04, 5/5/17 Comparison of MHE Field and Lab Data Voltage Durability CDP LAB 05, 5/3/2016 Data Set
Status of chemistry lab safety in Nepal.
Kandel, Krishna Prasad; Neupane, Bhanu Bhakta; Giri, Basant
2017-01-01
Chemistry labs can become a dangerous environment for students as the lab exercises involve hazardous chemicals, glassware, and equipment. Approximately one hundred thousand students take chemistry laboratory classes annually in Nepal. We conducted a survey on chemical lab safety issues across Nepal. In this paper, we assess the safety policy and equipment, protocols and procedures followed, and waste disposal in chemistry teaching labs. Significant population of the respondents believed that there is no monitoring of the lab safety in their lab (p<0.001). Even though many labs do not allow food and beverages inside lab and have first aid kits, they lack some basic safety equipment. There is no institutional mechanism to dispose lab waste and chemical waste is disposed haphazardly. Majority of the respondents believed that the safety training should be a part of educational training (p = 0.001) and they would benefit from short course and/or workshop on lab safety (p<0.001).
Status of chemistry lab safety in Nepal
Kandel, Krishna Prasad; Neupane, Bhanu Bhakta
2017-01-01
Chemistry labs can become a dangerous environment for students as the lab exercises involve hazardous chemicals, glassware, and equipment. Approximately one hundred thousand students take chemistry laboratory classes annually in Nepal. We conducted a survey on chemical lab safety issues across Nepal. In this paper, we assess the safety policy and equipment, protocols and procedures followed, and waste disposal in chemistry teaching labs. Significant population of the respondents believed that there is no monitoring of the lab safety in their lab (p<0.001). Even though many labs do not allow food and beverages inside lab and have first aid kits, they lack some basic safety equipment. There is no institutional mechanism to dispose lab waste and chemical waste is disposed haphazardly. Majority of the respondents believed that the safety training should be a part of educational training (p = 0.001) and they would benefit from short course and/or workshop on lab safety (p<0.001). PMID:28644869
Reflections on Three Corporate Research Labs: Bell Labs, HP Labs, Agilent Labs
NASA Astrophysics Data System (ADS)
Hollenhorst, James
2008-03-01
This will be a personal reflection on corporate life and physics-based research in three industrial research labs over three decades, Bell Labs during the 1980's, HP Labs during the 1990's, and Agilent Labs during the 2000's. These were times of great change in all three companies. I'll point out some of the similarities and differences in corporate cultures and how this impacted the research and development activities. Along the way I'll mention some of the great products that resulted from physics-based R&D.
2000-12-04
Viewed from inside Orbiter Processing Facility bay 3, Atlantis is ready for rollover to the Vehicle Assembly Building. In the VAB it will be raised to vertical and lifted up and into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
2000-12-04
The orbiter Atlantis rolls away from the Orbiter Processing Facility bay 3 (in the background) to the Vehicle Assembly Building. In the VAB it will be raised to vertical and lifted up and into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
2000-12-04
The orbiter Atlantis rolls toward the open door of the Vehicle Assembly Building after leaving the Orbiter Processing Facility bay 3. In the VAB it will be raised to vertical and lifted up and into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
2000-12-04
The orbiter Atlantis rolls toward the open door of the Vehicle Assembly Building after leaving the Orbiter Processing Facility bay 3. In the VAB it will be raised to vertical and lifted up and into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
2000-12-04
The orbiter Atlantis rolls out of the Orbiter Processing Facility bay 3 on its transporter. It is being transferred to the Vehicle Assembly Building where it will be raised to vertical and lifted up and into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
2000-12-04
Viewed from inside Orbiter Processing Facility bay 3, Atlantis is ready for rollover to the Vehicle Assembly Building. In the VAB it will be raised to vertical and lifted up and into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
2000-12-04
The orbiter Atlantis, on its transporter, heads into the turn toward the Vehicle Assembly Building, in the background. In the VAB it will be raised to vertical and lifted up and into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
2000-12-04
The orbiter Atlantis rolls away from the Orbiter Processing Facility bay 3 (in the background) to the Vehicle Assembly Building. In the VAB it will be raised to vertical and lifted up and into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
2000-12-04
The orbiter Atlantis, on its transporter, heads into the turn toward the Vehicle Assembly Building, in the background. In the VAB it will be raised to vertical and lifted up and into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
2000-12-04
The orbiter Atlantis rolls out of the Orbiter Processing Facility bay 3 on its transporter. It is being transferred to the Vehicle Assembly Building where it will be raised to vertical and lifted up and into high bay 3 for stacking with its external tank and solid rocket boosters. Atlantis will fly on mission STS-98, the seventh construction flight to the International Space Station. The orbiter will carry in its payload bay the U.S. Laboratory, named Destiny, that will have five system racks already installed inside of the module. After delivery of electronics in the lab, electrically powered attitude control for Control Moment Gyroscopes will be activated. Atlantis is scheduled for launch on Jan. 18, 2001, at 2:44 a.m. EST, with a crew of five
Gu, Li-Qun; Ding, Shu; Gao, Changlu
2011-01-01
The molecular-scale pore structure, called nanopore, can be formed from protein ion channels by genetic engineering or fabricated on solid substrates using fashion nanotechnology. Target molecules in interaction with the functionalized lumen of nanopore, can produce characteristic changes in the pore conductance, which act as fingerprints, allowing us to identify single molecules and simultaneously quantify each target species in the mixture. Nanopore sensors have been created for tremendous biomedical detections, with targets ranging from metal ions, drug compounds and cellular second messengers, to proteins and DNAs. Here we will review our recent discoveries with a lab-in-hand glass nanopore: single-molecule discrimination of chiral enantiomers with a trapped cyclodextrin, and sensing of bioterrorist agent ricin. PMID:19964179
NASA Astrophysics Data System (ADS)
Wang, Shifeng; Wang, Rui; Zhang, Pengfei; Dai, Xiang; Gong, Dawei
2017-08-01
One of the motivations of OptoBot Lab is to train primer students into qualified engineers or researchers. The series training programs have been designed by supervisors and implemented with tutoring for students to test and practice their knowledge from textbooks. An environment perception experiment using a 32 layers laser scanner is described in this paper. The training program design and laboratory operation is introduced. The four parts of the experiments which are preparation, sensor calibration, 3D space reconstruction, and object recognition, are the participating students' main tasks for different teams. This entire program is one of the series training programs that play significant role in establishing solid research skill foundation for opto-electronic students.
Pu, Fan; McKinney, Andrew R; Stenhouse, Allen M; Suann, Craig J; McLeod, Malcolm D
2004-12-25
A study of the equine phase II metabolism of the anabolic agent boldenone is reported. Boldenone sulfate, boldenone glucuronide and their C17-epimers were synthesised as reference standards in our lab and a method was developed for their detection in a horse urine matrix. Solid phase extraction was used to purify the analytes, which were then detected by ion trap LC/MS. Negative and positive ionisation mode MS(2) were used for the detection of sulfate and glucuronide conjugates, respectively. Boldenone sulfate and 17-epiboldenone glucuronide were detected as the major and minor phase II metabolites, respectively, in horse urine samples collected following the administration of boldenone undecylenate by intramuscular injection.
2007-07-03
KENNEDY SPACE CENTER, FLA. -- The main engines on the orbiter Endeavour (upper right) are seen as Endeavour is lowered into high bay 1 of the Vehicle Assembly Building for stacking with the external tank (seen at left) and solid rocket boosters on the mobile launcher platform. Endeavour will be launched on mission STS-118, its first flight in more than four years. The shuttle has undergone extensive modifications, including the addition of safety upgrades already added to shuttles Discovery and Atlantis. Endeavour also features new hardware, such as the Station-to-Shuttle Power Transfer System that will allow the docked shuttle to draw electrical power from the station and extend its visits to the orbiting lab. Endeavour is targeted for launch on Aug. 7. Photo credit: NASA/Troy Cryder
NASA Astrophysics Data System (ADS)
Xu, Chang-Qing; Gan, Yi; Sun, Jian
2012-03-01
Laser displays require red, green and blue (RGB) laser sources each with a low-cost, a high wall-plug efficiency, and a small size. However, semiconductor chips that directly emit green light with sufficient power and efficiency are not currently available on the market. A practical solution to the "green" bottleneck is to employ diode pumped solid state laser (DPSSL) technology, in which a frequency doubling crystal is used. In this paper, recent progress of MgO doped periodically poled lithium niobate (MgO:PPLN) frequency doubling optical chips will be presented. It is shown that MgO:PPLN can satisfy all of the requirements for laser displays and is ready for mass production.
Beam-Target Helicity Asymmetry for γ → n → → π - p in the N * Resonance Region
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ho, D.; Peng, P.; Bass, C.
2017-06-01
We report the first beam-target double-polarization asymmetries in the gamma+n(p)->pi(-)+p(p) reaction spanning the nucleon resonance region from invariant mass W=1500 to 2300 MeV. Circularly polarized photons and longitudinally polarized deuterons in solid hydrogen deuteride (HD) have been used with the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The exclusive final state has been extracted using three very different analyses that show excellent agreement, and these have been used to deduce the E polarization observable for an effective neutron target. These results have been incorporated into new partial wave analyses and have led to significant revisions for several gamma nN*more » resonance photocouplings.« less
Think Scientifically: The NASA Solar Dynamics Observatory's Elementary Science Literacy Program
NASA Astrophysics Data System (ADS)
Van Norden, Wendy; Wawro, Martha
2013-03-01
The pressure to focus on math and reading at the elementary level has increased in recent years. As a result, science education has taken a back seat in elementary classrooms. The Think Scientifically book series provides a way for science to easily integrate with existing math and reading curriculum. This story-based science literature program integrates a classic storybook format with solid solar science, to make an educational product that meets state literacy standards. Each story is accompanied by hands-on labs and activities that teachers can easily conduct in their classrooms with minimal training and materials, as well as math and language arts extensions and assessment questions. These books are being distributed through teacher workshops and conferences.
Think Scientifically: The Solar Dynamics Observatory's Elementary Science Literacy Program
NASA Astrophysics Data System (ADS)
Van Norden, Wendy; Wawro; Martha
2012-03-01
The pressure to focus on math and reading at the elementary level has increased in recent years. As a result, science education has taken a back seat in elementary classrooms. The Think Scientifically book series provides a way for science to easily integrate with existing math and reading curriculum. This story-based science literature program integrates a classic storybook format with solid solar science, to make an educational product that meets state literacy standards. Each story is accompanied by hands-on labs and activities that teachers can easily conduct in their classrooms with minimal training and materials, as well as math and language arts extensions and assessment questions. These books are being distributed through teacher workshops and conferences.
Beam-Target Helicity Asymmetry for γ[over →]n[over →]→π^{-}p in the N^{*} Resonance Region.
Ho, D; Peng, P; Bass, C; Collins, P; D'Angelo, A; Deur, A; Fleming, J; Hanretty, C; Kageya, T; Khandaker, M; Klein, F J; Klempt, E; Laine, V; Lowry, M M; Lu, H; Nepali, C; Nikonov, V A; O'Connell, T; Sandorfi, A M; Sarantsev, A V; Schumacher, R A; Strakovsky, I I; Švarc, A; Walford, N K; Wei, X; Whisnant, C S; Workman, R L; Zonta, I; Adhikari, K P; Adikaram, D; Akbar, Z; Amaryan, M J; Anefalos Pereira, S; Avakian, H; Ball, J; Bashkanov, M; Battaglieri, M; Batourine, V; Bedlinskiy, I; Biselli, A; Briscoe, W J; Burkert, V D; Carman, D S; Celentano, A; Charles, G; Chetry, T; Ciullo, G; Clark, L; Colaneri, L; Cole, P L; Contalbrigo, M; Crede, V; Dashyan, N; De Sanctis, E; De Vita, R; Djalali, C; Dupre, R; El Alaoui, A; El Fassi, L; Elouadrhiri, L; Eugenio, P; Fedotov, G; Fegan, S; Fersch, R; Filippi, A; Fradi, A; Ghandilyan, Y; Gilfoyle, G P; Girod, F X; Glazier, D I; Gleason, C; Gohn, W; Golovatch, E; Gothe, R W; Griffioen, K A; Guidal, M; Guo, L; Hakobyan, H; Harrison, N; Hattawy, M; Hicks, K; Holtrop, M; Hughes, S M; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Jenkins, D; Jiang, H; Jo, H S; Joo, K; Joosten, S; Keller, D; Khachatryan, G; Kim, A; Kim, W; Klein, A; Kubarovsky, V; Kuleshov, S V; Lanza, L; Lenisa, P; Livingston, K; MacGregor, I J D; Markov, N; McKinnon, B; Mineeva, T; Mokeev, V; Montgomery, R A; Movsisyan, A; Munoz Camacho, C; Murdoch, G; Niccolai, S; Niculescu, G; Osipenko, M; Paolone, M; Paremuzyan, R; Park, K; Pasyuk, E; Phelps, W; Pogorelko, O; Price, J W; Procureur, S; Protopopescu, D; Ripani, M; Riser, D; Ritchie, B G; Rizzo, A; Rosner, G; Sabatié, F; Salgado, C; Sharabian, Y G; Skorodumina, Iu; Smith, G D; Sober, D I; Sokhan, D; Sparveris, N; Strauch, S; Tian, Ye; Torayev, B; Ungaro, M; Voskanyan, H; Voutier, E; Watts, D P; Wood, M H; Zachariou, N; Zhang, J; Zhao, Z W
2017-06-16
We report the first beam-target double-polarization asymmetries in the γ+n(p)→π^{-}+p(p) reaction spanning the nucleon resonance region from invariant mass W=1500 to 2300 MeV. Circularly polarized photons and longitudinally polarized deuterons in solid hydrogen deuteride (HD) have been used with the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The exclusive final state has been extracted using three very different analyses that show excellent agreement, and these have been used to deduce the E polarization observable for an effective neutron target. These results have been incorporated into new partial wave analyses and have led to significant revisions for several γnN^{*} resonance photocouplings.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hasan, M.A.; Selim, Y.T.; Lasheen, Y.F.
2013-07-01
The application of radioisotopes and radiation sources in medical diagnosis and therapy is an important issue. Physicians can use radioisotopes to diagnose and treat diseases. Methods of treatment, conditioning and management of low level radioactive wastes from the use of radiation sources and radioisotopes in hospitals and nuclear medicine application, are described. Solid Radioactive waste with low-level activity after accumulation, minimization, segregation and measurement, are burned or compressed in a compactor according to the international standards. Conditioned drums are transported to the interim storage site at the Egyptian Atomic Energy Authority (EAEA) represented in Hot Labs and Waste Management Centermore » (HLWMC) for storage and monitoring. (authors)« less
NASA Astrophysics Data System (ADS)
Weeks, Eric R.; Cianci, Gianguido; Habdas, Piotr
2008-03-01
Our laboratory studies soft condensed matter, which means we investigate squishy materials such as foams, emulsions, and colloidal suspensions. These materials include common things such as peanut butter, toothpaste, mayonnaise, shampoo, and shaving cream. We have conducted several field trips for grade school students, where they come to our laboratory and play with squishy materials. They do both hands-on table-top projects and also look at samples with a microscope. We have also developed some of these activities into labs appropriate for first-year college students. Our first goal for these activities is to show students that science is fun, and the second goal is to get them intrigued by the idea that there are more phases than just solids, liquids, and gases.
Kinematic Labs with Mobile Devices
NASA Astrophysics Data System (ADS)
Kinser, Jason M.
2015-07-01
This book provides 13 labs spanning the common topics in the first semester of university-level physics. Each lab is designed to use only the student's smartphone, laptop and items easily found in big-box stores or a hobby shop. Each lab contains theory, set-up instructions and basic analysis techniques. All of these labs can be performed outside of the traditional university lab setting and initial costs averaging less than 8 per student, per lab.
NASA Astrophysics Data System (ADS)
Balakrishnan, B.; Woods, P. C.
2013-05-01
Over the years, rapid development in computer technology has engendered simulation-based laboratory (lab) in addition to the traditional hands-on (physical) lab. Many higher education institutions adopt simulation lab, replacing some existing physical lab experiments. The creation of new systems for conducting engineering lab activities has raised concerns among educators on the merits and shortcomings of both physical and simulation labs; at the same time, many arguments have been raised on the differences of both labs. Investigating the effectiveness of both labs is complicated, as there are multiple factors that should be considered. In view of this challenge, a study on students' perspectives on their experience related to key aspects on engineering laboratory exercise was conducted. In this study, the Visual Auditory Read and Kinetic model was utilised to measure the students' cognitive styles. The investigation was done through a survey among participants from Multimedia University, Malaysia. The findings revealed that there are significant differences for most of the aspects in physical and simulation labs.
TangoLab-2 Card Troubleshooting
2017-10-17
iss053e105442 (Oct. 17, 2017) --- Flight Engineer Mark Vande Hei swaps out a payload card from the TangoLab-1 facility and places into the TangoLab-2 facility. TangoLab provides a standardized platform and open architecture for experimental modules called CubeLabs. CubeLab modules may be developed for use in 3-dimensional tissue and cell cultures.
MatLab Script and Functional Programming
NASA Technical Reports Server (NTRS)
Shaykhian, Gholam Ali
2007-01-01
MatLab Script and Functional Programming: MatLab is one of the most widely used very high level programming languages for scientific and engineering computations. It is very user-friendly and needs practically no formal programming knowledge. Presented here are MatLab programming aspects and not just the MatLab commands for scientists and engineers who do not have formal programming training and also have no significant time to spare for learning programming to solve their real world problems. Specifically provided are programs for visualization. The MatLab seminar covers the functional and script programming aspect of MatLab language. Specific expectations are: a) Recognize MatLab commands, script and function. b) Create, and run a MatLab function. c) Read, recognize, and describe MatLab syntax. d) Recognize decisions, loops and matrix operators. e) Evaluate scope among multiple files, and multiple functions within a file. f) Declare, define and use scalar variables, vectors and matrices.
NASA Astrophysics Data System (ADS)
Abbaszadeh, Shiva; Karim, Karim S.; Karanassios, Vassili
2013-05-01
Traditionally, samples are collected on-site (i.e., in the field) and are shipped to a lab for chemical analysis. An alternative is offered by using portable chemical analysis instruments that can be used on-site (i.e., in the field). Many analytical measurements by optical emission spectrometry require use of light-sources and of spectral lines that are in the Ultra-Violet (UV, ~200 nm - 400 nm wavelength) region of the spectrum. For such measurements, a portable, battery-operated, fiber-optic spectrometer equipped with an un-cooled, linear, solid-state detector may be used. To take full advantage of the advanced measurement capabilities offered by state-of-the-art solid-state detectors, cooling of the detector is required. But cooling and other thermal management hamper portability and use on-site because they add size and weight and they increase electrical power requirements. To address these considerations, an alternative was implemented, as described here. Specifically, a microfabricated solid-state detector for measurement of UV photons will be described. Unlike solid-state detectors developed on crystalline Silicon, this miniaturized and low-cost detector utilizes amorphous Selenium (a-Se) as its photosensitive material. Due to its low dark current, this detector does not require cooling, thus it is better suited for portable use and for chemical measurements on-site. In this paper, a microplasma will be used as a light-source of UV photons for the a-Se detector. For example, spectra acquired using a microplasma as a light-source will be compared with those obtained with a portable, fiber-optic spectrometer equipped with a Si-based 2080-element detector. And, analytical performance obtained by introducing ng-amounts of analytes into the microplasma will be described.
Hydrogen generation via anaerobic fermentation of paper mill wastes.
Valdez-Vazquez, Idania; Sparling, Richard; Risbey, Derek; Rinderknecht-Seijas, Noemi; Poggi-Varaldo, Héctor M
2005-11-01
The objective of this work was to determine the hydrogen production from paper mill wastes using microbial consortia of solid substrate anaerobic digesters. Inocula from mesophilic, continuous solid substrate anaerobic digestion (SSAD) reactors were transferred to small lab scale, batch reactors. Milled paper (used as a surrogate paper waste) was added as substrate and acetylene or 2-bromoethanesulfonate (BES) was spiked for methanogenesis inhibition. In the first phase of experiments it was found that acetylene at 1% v/v in the headspace was as effective as BES in inhibiting methanogenic activity. Hydrogen gas accumulated in the headspace of the bottles, reaching a plateau. Similar final hydrogen concentrations were obtained for reactors spiked with acetylene and BES. In the second phase of tests the headspace of the batch reactors was flushed with nitrogen gas after the first plateau of hydrogen was reached, and subsequently incubated, with no further addition of inhibitor nor substrate. It was found that hydrogen production resumed and reached a second plateau, although somewhat lower than the first one. This procedure was repeated a third time and an additional amount of hydrogen was obtained. The plateaux and initial rates of hydrogen accumulation decreased in each subsequent incubation cycle. The total cumulative hydrogen harvested in the three cycles was much higher (approx. double) than in the first cycle alone. We coined this procedure as IV-SSAH (intermittently vented solid substrate anaerobic hydrogen generation). Our results point out to a feasible strategy for obtaining higher hydrogen yields from the fermentation of industrial solid wastes, and a possible combination of waste treatment processes consisting of a first stage IV-SSAH followed by a second SSAD stage. Useful products of this approach would be hydrogen, organic acids or methane, and anaerobic digestates that could be used as soil amenders after post-treatment.
Solid State Light Evaluation in the U.S. Lab Mockup
NASA Technical Reports Server (NTRS)
Maida, James c.; Bowen, Charles K.; Wheelwright, Chuck
2009-01-01
This document constitutes the publication of work performed by the Space Human Factors Laboratory (mail code SF5 at the time) at the Johnson Space Center (JSC) in the months of June and July of 2000. At that time, the Space Human Factors Laboratory was part of the Space Human Factors Branch in the Flight Projects Division of the Space and Life Directorate. This report was originally to be a document for internal consumption only at JSC as it was seen to be only preliminary work for the further development of solid state illumination for general lighting on future space vehicles and the International Space Station (ISS). Due to funding constraints, immediate follow-on efforts were delayed and the need for publication of this document was overcome by other events. However, in recent years and with the development and deployment of a solid state light luminaire prototype on ISS, the time was overdue for publishing this information for general distribution and reference. Solid state lights (SSLs) are being developed to potentially replace the general luminaire assemblies (GLAs) currently in service in the International Space Station (ISS) and included in designs of modules for the ISS. The SSLs consist of arrays of light emitting diodes (LEDs), small solid state electronic devices that produce visible light in proportion to the electrical current flowing through them. Recent progressive advances in electrical power-to-light conversion efficiency in LED technology have allowed the consideration of LEDs as replacements for incandescent and fluorescent light sources in many circumstances, and their inherent advantages in ruggedness, reliability, and life expectancy make them attractive for applications in spacecraft. One potential area of application for the SSLs in the U.S. Laboratory Module of the ISS. This study addresses the suitability of the SSLs as replacements for the GLAs in this application.
An Evaluation of Two Hands-On Lab Styles for Plant Biodiversity in Undergraduate Biology
ERIC Educational Resources Information Center
Basey, John M.; Maines, Anastasia P.; Francis, Clinton D.; Melbourne, Brett
2014-01-01
We compared learning cycle and expository formats for teaching about plant biodiversity in an inquiry-oriented university biology lab class (n = 465). Both formats had preparatory lab activities, a hands-on lab, and a postlab with reflection and argumentation. Learning was assessed with a lab report, a practical quiz in lab, and a multiple-choice…
NASA Astrophysics Data System (ADS)
Holmes, N. G.; Olsen, Jack; Thomas, James L.; Wieman, Carl E.
2017-06-01
Instructional labs are widely seen as a unique, albeit expensive, way to teach scientific content. We measured the effectiveness of introductory lab courses at achieving this educational goal across nine different lab courses at three very different institutions. These institutions and courses encompassed a broad range of student populations and instructional styles. The nine courses studied had two key things in common: the labs aimed to reinforce the content presented in lectures, and the labs were optional. By comparing the performance of students who did and did not take the labs (with careful normalization for selection effects), we found universally and precisely no added value to learning course content from taking the labs as measured by course exam performance. This work should motivate institutions and departments to reexamine the goals and conduct of their lab courses, given their resource-intensive nature. We show why these results make sense when looking at the comparative mental processes of students involved in research and instructional labs, and offer alternative goals and instructional approaches that would make lab courses more educationally valuable.
NASA Technical Reports Server (NTRS)
Bernstein, Max; Sandford, Scott; Cruikshank, Dale
2005-01-01
Infrared (IR) spectra have demonstrated that solid H2O is very common in the outer Solar System, and solid carbon dioxide (CO2) has been detected on icy satellites, comets, and planetismals throughout the outer Solar System. In such environments, CO2 and H2O must sometimes be mixed at a molecular level, changing their IR absorption features. In fact, the IR spectra of CO2-H2O mixtures are not equivalent to a linear combination of the spectra of the pure materials. Laboratory IR spectra of pure CO2 and H2O have been published but a lack of near-IR spectra of CO2-H2O mixtures has made the interpretation of outer Solar System spectra more difficult. We present near infrared (IR) spectra of CO2 in H2O and in CH3OH compared to that of pure solid CO2 and find significant differences. Peaks not present in either pure H2O or pure CO2 spectra become evident. First, the CO2 (2nu(sub 3)) overtone near 2.134 micron (4685/ cm) that is not seen in pure solid CO2 is prominent in the spectrum of a CO2/H2O = 25 mixture. Second, a 2.74 micron (3650/ cm) dangling OH feature of water (and a potentially related peak at 1.89 micron) appear in the spectra of CO2-H2O ice mixtures, but may not be specific to the presence of CO2. Other CO2 peaks display shifts in position and increased width because of intermolecular interactions with water. Changes in CO2 peak positions and profiles on warming of a CO2/H2O = 5 mixture are consistent with 'segregation' of the ice into nearly pure separate components. Absolute strengths for absorptions of CO2 in solid H2O are estimated. Similar results are observed for CO2 in solid CH3OH. Since the CO2 ( 2nu(sub 3)) overtone near 2.134 micron (4685/ cm) is not present in pure CO2 but prominent in mixtures it may be a good observational indicator of whether solid CO2 is a pure material or intimately mixed with other molecules. Significant changes in the near IR spectrum of solid CO2 in the presence of H2O and CH3OH means that the abundance of solid CO2 in the outer Solar System may have been under-estimated in those environments where solid CO2 and H2O or CH3OH are mixed.
Teachers' Perspectives on Online Virtual Labs vs. Hands-On Labs in High School Science
NASA Astrophysics Data System (ADS)
Bohr, Teresa M.
This study of online science teachers' opinions addressed the use of virtual labs in online courses. A growing number of schools use virtual labs that must meet mandated laboratory standards to ensure they provide learning experiences comparable to hands-on labs, which are an integral part of science curricula. The purpose of this qualitative case study was to examine teachers' perceptions of the quality and effectiveness of high school virtual labs. The theoretical foundation was constructivism, as labs provide student-centered activities for problem solving, inquiry, and exploration of phenomena. The research questions focused on experienced teachers' perceptions of the quality of virtual vs. hands-on labs. Data were collected through survey questions derived from the lab objectives of The Next Generation Science Standards . Eighteen teachers rated the degree of importance of each objective and also rated how they felt virtual labs met these objectives; these ratings were reported using descriptive statistics. Responses to open-ended questions were few and served to illustrate the numerical results. Many teachers stated that virtual labs are valuable supplements but could not completely replace hands-on experiences. Studies on the quality and effectiveness of high school virtual labs are limited despite widespread use. Comprehensive studies will ensure that online students have equal access to quality labs. School districts need to define lab requirements, and colleges need to specify the lab experience they require. This study has potential to inspire positive social change by assisting science educators, including those in the local school district, in evaluating and selecting courseware designed to promote higher order thinking skills, real-world problem solving, and development of strong inquiry skills, thereby improving science instruction for all high school students.
The Influence of Tablet PCs on Students' Use of Multiple Representations in Lab Reports
NASA Astrophysics Data System (ADS)
Guelman, Clarisa Bercovich; De Leone, Charles; Price, Edward
2009-11-01
This study examined how different tools influenced students' use of representations in the Physics laboratory. In one section of a lab course, every student had a Tablet PC that served as a digital-ink based lab notebook. Students could seamlessly create hand-drawn graphics and equations, and write lab reports on the same computer used for data acquisition, simulation, and analysis. In another lab section, students used traditional printed lab guides, kept paper notebooks, and then wrote lab reports on regular laptops. Analysis of the lab reports showed differences between the sections' use of multiple representations, including an increased use of diagrams and equations by the Tablet users.
NASA Astrophysics Data System (ADS)
Yang, W. M.; Chen, L. P.; Wang, X. J.
2016-02-01
High quality single domain YBCO bulk superconductors, 20 mm in diameter, have been fabricated using a new top seeded infiltration and growth method (called the RE + 011 TSIG method), with a new solid phase (Y2O3 + xBaCuO2) instead of the conventional Y2BaCuO5 solid phase, x = 0, 0.5, 1.0, 1.2, 1.5, 1.8, 2.0, 2.5, 3.0. The effects of different BaCuO2 contents x on the growth morphology, microstructure, and levitation force have been investigated. The results show that the levitation force of the YBCO bulks first increases and then decreases with increasing x, and reaches maximum levitation forces of about 49.2 N (77 K, 0.5 T, with the traditional liquid phase of YBa2Cu3O y + 3 BaCuO2 + 2 CuO) and 47 N (77.3 K, 0.5 T, with the new liquid phase of Y2O3 + 10 BaCuO2 + 6 CuO) when x = 1.2, which is much higher than that of the samples fabricated with the conventional solid phases (23 N). The average Y2BaCuO5 particle size is about 1 μm, which is much smaller than the 3.4 μm in the samples prepared with the conventional Y2BaCuO5 solid phase; this means that the flux pinning force of the sample can be improved by using the new solid phase. Based on this method, single domain YBCO bulks 40 mm, 59 mm, and 93 mm in diameter have also been fabricated using the TSIG process with the new solid phases (Y2O3 + 1.2BaCuO2). These results indicate that the new TSIG process developed by our lab is a very important and practical method for the fabrication of low cost, large size, and high quality single domain REBCO bulk superconductors.
Dizge, Nadir
2014-01-01
The objectives of this investigation were to perform a series of lab-scale membrane separation experiments under various operating conditions to investigate the performance behaviour of nanofiltration membrane (NF 270) for wastewater reuse from the wood-panels industry. The operating condition effects, e.g. cross-flow velocity (CFV), trans membrane pressure (TMP) and temperature, on the permeate flux and contaminant rejection efficiency were investigated. Moreover, three different samples: (1) raw wastewater collected from the wood-panels industry; (2) ultrafiltration pre-treated wastewater (UF-NF); and (3) coagulation/flocculation pre-treated wastewater (CF-NF) were employed in this study. The UF-NF was proposed as a pre-treatment process because it could reduce the chemical oxygen demand (COD) effectively with lower energy consumption than CF-NF. The performance of NF 270 membrane was assessed by measurements of the many parameters (pH, conductivity, total dissolved solids, COD, suspended solids, total nitrogen, nitrite, nitrate, and total phosphate) under various operating conditions. It was noted that the contaminant rejection was affected by changing TMP and CFV. It was concluded that the purified water stream can be recycled into the process for water reuse or safely disposed to the river.
Using Omega and NIF to Advance Theories of High-Pressure, High-Strain-Rate Tantalum Plastic Flow
NASA Astrophysics Data System (ADS)
Rudd, R. E.; Arsenlis, A.; Barton, N. R.; Cavallo, R. M.; Huntington, C. M.; McNaney, J. M.; Orlikowski, D. A.; Park, H.-S.; Prisbrey, S. T.; Remington, B. A.; Wehrenberg, C. E.
2015-11-01
Precisely controlled plasmas are playing an important role as both pump and probe in experiments to understand the strength of solid metals at high energy density (HED) conditions. In concert with theory, these experiments have enabled a predictive capability to model material strength at Mbar pressures and high strain rates. Here we describe multiscale strength models developed for tantalum and vanadium starting with atomic bonding and extending up through the mobility of individual dislocations, the evolution of dislocation networks and so on up to full scale. High-energy laser platforms such as the NIF and the Omega laser probe ramp-compressed strength to 1-5 Mbar. The predictions of the multiscale model agree well with the 1 Mbar experiments without tuning. The combination of experiment and theory has shown that solid metals can behave significantly differently at HED conditions; for example, the familiar strengthening of metals as the grain size is reduced has been shown not to occur in the high pressure experiments. Work performed under the auspices of the U.S. Dept. of Energy by Lawrence Livermore National Lab under contract DE-AC52-07NA273.
Droplets and the three-phase contact line at the nano-scale. Statics and dynamics
NASA Astrophysics Data System (ADS)
Yatsyshin, Petr; Sibley, David; Savva, Nikos; Kalliadasis, Serafim
2014-11-01
Understanding the behaviour of the solid-liquid-vapour contact line at the scale of several tens of molecular diameters is important in wetting hydrodynamics with applications in micro- and nano-fluidics, including the design of lab-on-a-chip devices and surfaces with specific wetting properties. Due to the fluid inhomogeneity at the nano-scale, the application of continuum-mechanical approaches is limited, and a natural way to remedy this is to seek descriptions accounting for the non-local molecular-level interactions. Density Functional Theory (DFT) for fluids offers a statistical-mechanical framework based on expressing the free energy of the fluid-solid pair as a functional of the spatially varying fluid density. DFT allows us to investigate small drops deposited on planar substrates whilst keeping track of the microscopic structural details of the fluid. Starting from a model of intermolecular forces, we systematically obtain interfaces, surface tensions, and the microscopic contact angle. Using a dynamic extension of equilibrium DFT, we investigate the diffusion-driven evolution of the three-phase contact line to gain insight into the dynamic behaviour of the microscopic contact angle, which is still under debate.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ischia, Marco, E-mail: marco.ischia@ing.unitn.it; Maschio, Roberto Dal; Grigiante, Maurizio
2011-01-15
Wastewater sewage sludge was co-pyrolyzed with a well characterized clay sample, in order to evaluate possible advantages in the thermal disposal process of solid waste. Characterization of the co-pyrolysis process was carried out both by thermogravimetric-mass spectrometric (TG-MS) analysis, and by reactor tests, using a lab-scale batch reactor equipped with a gas chromatograph for analysis of the evolved gas phase (Py-GC). Due to the presence of clay, two main effects were observed in the instrumental characterization of the process. Firstly, the clay surface catalyzed the pyrolysis reaction of the sludge, and secondly, the release of water from the clay, atmore » temperatures of approx. 450-500 deg. C, enhanced gasification of part of carbon residue of the organic component of sludge following pyrolysis. Moreover, the solid residue remaining after pyrolysis process, composed of the inorganic component of sludge blended with clay, is characterized by good features for possible disposal by vitrification, yielding a vitreous matrix that immobilizes the hazardous heavy metals present in the sludge.« less
Feng, Juanjuan; Sun, Min; Bu, Yanan; Luo, Chuannan
2015-01-01
A novel nanostructured copper-based solid-phase microextraction fiber was developed and applied for determining the two most common types of phthalate environmental estrogens (dibutyl phthalate and diethylhexyl phthalate) in aqueous samples, coupled to gas chromatography with flame ionization detection. The copper film was coated onto a stainless-steel wire via an electroless plating process, which involved a surface activation process to improve the surface properties of the fiber. Several parameters affecting extraction efficiency such as extraction time, extraction temperature, ionic strength, desorption temperature, and desorption time were optimized by a factor-by-factor procedure to obtain the highest extraction efficiency. The as-established method showed wide linear ranges (0.05-250 μg/L). Precision of single fiber repeatability was <7.0%, and fiber-to-fiber repeatability was <10%. Limits of detection were 0.01 μg/L. The proposed method exhibited better or comparable extraction performance compared with commercial and other lab-made fibers, and excellent thermal stability and durability. The proposed method was applied successfully for the determination of model analytes in plastic soaking water. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Bella, Federico; Popovic, Jelena; Lamberti, Andrea; Tresso, Elena; Gerbaldi, Claudio; Maier, Joachim
2017-11-01
With the purpose of achieving stable dye-sensitized solar cells (DSSCs) with high efficiency, a new type of soft matter electrolyte is tested in which specific amounts of nanosized silica particles are finely dispersed in short-chained polyethylene glycol dimethylether encompassing an iodide/triiodide redox mediator. This results in a solid-liquid composite having synergistic electrical and favorable mechanical properties. The combination of interfacial effects and particle network formation promotes enhanced ion transport, which directly impacts the short-circuit photocurrent density. Thorough analysis reveals that this newly elaborated class of electrolytes is able to improve, at the same time, the thermal and long-term stability of DSSCs, as well as power conversion efficiency under standard and lower irradiation intensities. Lab-scale devices with champion efficiency exceeding 11% under attenuated sunlight (20 mW cm -2 , with a compact TiO 2 blocking layer) are obtained, along with impressively stable performance under both thermal stress and light soaking in an indoor environment (>96% performance retention after 2500 h of accelerated aging under full sun alternated with thermal ramps), matching the durability criteria applied to silicon solar cells for outdoor applications. The new findings might foster widespread practical application of DSSCs.
Bio-diatomite dynamic membrane reactor for micro-polluted surface water treatment.
Chu, Huaqiang; Cao, Dawen; Dong, Bingzhi; Qiang, Zhimin
2010-03-01
This work investigated the feasibility of treating micro-polluted surface water for drinking water production with a bio-diatomite dynamic membrane reactor (BDDMR) at lab-scale in continuous-flow mode. Results indicate that the BDDMR was effective in removing COD(Mn), DOC, UV(254), NH(3)-N and trihalomethanes' formation potential (THMFP) at a hydraulic retention time (HRT) of 3.5h due to its high concentrations of mixed liquor suspended solids (MLSS) and mixed liquor volatile suspended solids (MLVSS). The removal of pollutants was mainly ascribed to microbial degradation in BDDMR because the dynamic membrane alone was much less effective in pollutant removal. Though the diatomite particles (5-20microm) were much smaller in size than the aperture of the stainless steel support mesh (74microm), microorganisms and their extracellular polymer substances could bind these particles tightly to form bio-diatomite particles which were completely retained by the support mesh. The analysis of molecular weight (MW) distribution by gel permeation chromatography (GPC) shows that the BDDMR could effectively remove the hydrophilic fraction of dissolved organic materials present in the raw water. Copyright 2009 Elsevier Ltd. All rights reserved.
Cho, Hyun Uk; Park, Sang Kyu; Ha, Jeong Hyub; Park, Jong Moon
2013-11-15
Lab-scale High Efficiency Digestion (HED) systems containing a Mesophilic Anaerobic Reactor (MAR), Thermophilic Aerobic Reactor (TAR), liquid/solid separation unit, and thermal-alkaline treatment were developed to evaluate the efficiencies of sludge reduction and methane production. The HED process was divided into three phases to examine the influence of sludge pretreatment and pretreated sludge recirculation using TCOD and VSS reduction, COD solubilization, and methane production. The VSS removal with a solid/liquid separation unit, sludge recirculation, and thermal-alkaline treatment drastically increased up to 95% compared to the feed concentration. In addition, the results of COD solubilization and VSS/TSS showed that the solubilization of cells and organic matters by the thermal-alkaline treatment was highly increased, which was also consistent with the SEM images. In particular, the methane production rate increased 24-fold when the feed sludge and recirculated sludge were pretreated together. Collectively, the HED experiments performed with sludge recirculation and thermal-alkaline treatment demonstrated that the HED systems can be successfully employed for highly efficient sewage sludge reduction and methane gas production. Copyright © 2013 Elsevier Ltd. All rights reserved.
Concentration Waves in High-Entropy Alloys - a new alloy design approach
NASA Astrophysics Data System (ADS)
Singh, Prashant; Johnson, Duane D.
2015-03-01
Chemical short-range order (SRO) in solid solutions can be interpreted as a ``concentration wave'' - a Fourier decomposition of nascent order - identified experimentally via Warren-Cowley SRO parameters. We present a rigorous thermodynamic theory to predict and uniquely interpret the SRO in N -component alloys. Based on KKR-CPA electronic structure, we implemented this method using thermodynamic linear-response to include all alloying effects, e.g., band-filling, hybridization, Fermi -surface nesting and van Hove instabilities. We apply this first-principles method to high-entropy alloys (HEAs), i.e., solid solutions with N >4 that inhibit small-cell order due to large entropy competing against ordering enthalpy, as their properties are sensitive to SRO. We validated theory with comparison to experiments in A2 Nb-Al-Ti and A1 Cu-Ni-Zn . We then predict and analyze SRO and mechanical trends in Ni-Ti-Zr-Cu-Al and Co-Cr-Fe-Mn-Ni systems - showcasing this new first-principles-based alloy design method. Work was supported by the USDoE, Office of Sci., Basic Energy Sci., Materials Sci. and Eng. Division for `Materials Discovery.' Research was performed at Ames Lab, operated by Iowa State University under Contract #DE-AC02-07CH11358.
Integrating Multiple On-line Knowledge Bases for Disease-Lab Test Relation Extraction.
Zhang, Yaoyun; Soysal, Ergin; Moon, Sungrim; Wang, Jingqi; Tao, Cui; Xu, Hua
2015-01-01
A computable knowledge base containing relations between diseases and lab tests would be a great resource for many biomedical informatics applications. This paper describes our initial step towards establishing a comprehensive knowledge base of disease and lab tests relations utilizing three public on-line resources. LabTestsOnline, MedlinePlus and Wikipedia are integrated to create a freely available, computable disease-lab test knowledgebase. Disease and lab test concepts are identified using MetaMap and relations between diseases and lab tests are determined based on source-specific rules. Experimental results demonstrate a high precision for relation extraction, with Wikipedia achieving the highest precision of 87%. Combining the three sources reached a recall of 51.40%, when compared with a subset of disease-lab test relations extracted from a reference book. Moreover, we found additional disease-lab test relations from on-line resources, indicating they are complementary to existing reference books for building a comprehensive disease and lab test relation knowledge base.
ERIC Educational Resources Information Center
Darrah, Marjorie; Humbert, Roxann; Finstein, Jeanne; Simon, Marllin; Hopkins, John
2014-01-01
Most physics professors would agree that the lab experiences students have in introductory physics are central to the learning of the concepts in the course. It is also true that these physics labs require time and money for upkeep, not to mention the hours spent setting up and taking down labs. Virtual physics lab experiences can provide an…
Effect of cyclophosphamide on the solid form of mannitol during lyophilization.
Patel, Krupaliben; Munjal, Bhushan; Bansal, Arvind K
2017-04-01
Mannitol is a commonly used bulking agent in lyophilized formulations. It can crystallize into multiple solid forms during lyophilization thereby exhibiting phase heterogeneity and variability in product performance. In this manuscript, we studied the effect of cyclophosphamide (CPA), an anticancer drug, on the solid form of mannitol during lyophilization from aqueous solutions. Freeze-concentration studies were performed in the DSC while lyophilization was performed in a lab scale freeze dryer. DSC experiments revealed two-stage crystallization of mannitol (1.5% w/v) during freeze-concentration, evident as two distinct exothermic events (at -18.2°C and -30°C) in the cooling curve. This was complemented by two eutectic melting endotherms in the subsequent heating curve. Addition of CPA (4.0% w/v) completely inhibited the exotherm at -18.2°C, but enhanced the enthalpy of exotherm at -30°C by five folds. Likewise, only one eutectic melting endotherm was observed in the subsequent heating curve. Lyophilization of the solution containing only mannitol, yielded a mixture of β- (major) and δ- (minor) polymorphs of mannitol. However, in the presence of CPA, only δ-polymorph was observed in the lyophilized sample. This selective favoring of the metastable δ-polymorph over the stable β-polymorph, was explained by altered freezing kinetics of the solution in presence of CPA. The study provides mechanistic insights into solute crystallization behaviour during lyophilization of multi-component systems. Copyright © 2017. Published by Elsevier B.V.
Efficient design of multituned transmission line NMR probes: the electrical engineering approach.
Frydel, J A; Krzystyniak, M; Pienkowski, D; Pietrzak, M; de Sousa Amadeu, N; Ratajczyk, T; Idzik, K; Gutmann, T; Tietze, D; Voigt, S; Fenn, A; Limbach, H H; Buntkowsky, G
2011-01-01
Transmission line-based multi-channel solid state NMR probes have many advantages regarding the cost of construction, number of RF-channels, and achievable RF-power levels. Nevertheless, these probes are only rarely employed in solid state-NMR-labs, mainly owing to the difficult experimental determination of the necessary RF-parameters. Here, the efficient design of multi-channel solid state MAS-NMR probes employing transmission line theory and modern techniques of electrical engineering is presented. As technical realization a five-channel ((1)H, (31)P, (13)C, (2)H and (15)N) probe for operation at 7 Tesla is described. This very cost efficient design goal is a multi port single coil transmission line probe based on the design developed by Schaefer and McKay. The electrical performance of the probe is determined by measuring of Scattering matrix parameters (S-parameters) in particular input/output ports. These parameters are compared to the calculated parameters of the design employing the S-matrix formalism. It is shown that the S-matrix formalism provides an excellent tool for examination of transmission line probes and thus the tool for a rational design of these probes. On the other hand, the resulting design provides excellent electrical performance. From a point of view of Nuclear Magnetic Resonance (NMR), calibration spectra of particular ports (channels) are of great importance. The estimation of the π/2 pulses length for all five NMR channels is presented. Copyright © 2011 Elsevier Inc. All rights reserved.
UASB-septic tank as an alternative for decentralized wastewater treatment in Mexico.
Santiago-Díaz, Ángel L; García-Albortante, Julisa; Salazar-Peláez, Mónica L
2018-02-05
The aim of this work was to evaluate the performance of a UASB-septic tank as a decentralized treatment of high-strength municipal wastewater under two different HRTs (48 and 72 h). Thus, a lab-scale (44.85 L) UASB-septic tank constituted by three compartments was operated under HRT 72 and 48 h. Removal efficiencies of total chemical oxygen demand (COD), biological oxygen demand (BOD 5 ) and suspended solids (SS) ranged from 60% to 80% for the first two parameters and from 70% to 90% for the last one. According to the statistical analysis, it was established that decreasing HRT from 72 to 48 h did not affect the performance of the UASB-septic tank; therefore, the latter HRT is recommended to be used for operation. In the first compartment, most of the organic matter removal was carried out, while the other two compartments served as polishing. Over the course of six months, the VS concentration and VS/TS ratio in sludge blanket decreased, indicating digestion and stabilization of the retained solids. Also, an increase of 4% in sludge volume was observed; thus, time for desludging would be approximately five years. Comparison of the UASB-septic tank and the UASB reactor showed that both systems had similar performance regarding effluent concentrations of organic matter and solids. Thus, under low volumetric organic load conditions (less than 20 mg COD/L h), the former is an attractive option for municipal wastewater treatment.
Evaluation of Petrifilm Lactic Acid Bacteria Plates for Counting Lactic Acid Bacteria in Food.
Kanagawa, Satomi; Ohshima, Chihiro; Takahashi, Hajime; Burenqiqige; Kikuchi, Misato; Sato, Fumina; Nakamura, Ayaka; Mohamed, Shimaa M; Kuda, Takashi; Kimura, Bon
2018-06-01
Although lactic acid bacteria (LAB) are used widely as starter cultures in the production of fermented foods, they are also responsible for food decay and deterioration. The undesirable growth of LAB in food causes spoilage, discoloration, and slime formation. Because of these adverse effects, food companies test for the presence of LAB in production areas and processed foods and consistently monitor the behavior of these bacteria. The 3M Petrifilm LAB Count Plates have recently been launched as a time-saving and simple-to-use plate designed for detecting and quantifying LAB. This study compares the abilities of Petrifilm LAB Count Plates and the de Man Rogosa Sharpe (MRS) agar medium to determine the LAB count in a variety of foods and swab samples collected from a food production area. Bacterial strains isolated from Petrifilm LAB Count Plates were identified by 16S rDNA sequence analysis to confirm the specificity of these plates for LAB. The results showed no significant difference in bacterial counts measured by using Petrifilm LAB Count Plates and MRS medium. Furthermore, all colonies growing on Petrifilm LAB Count Plates were confirmed to be LAB, while yeast colonies also formed in MRS medium. Petrifilm LAB Count Plates eliminated the plate preparation and plate inoculation steps, and the cultures could be started as soon as a diluted food sample was available. Food companies are required to establish quality controls and perform tests to check the quality of food products; the use of Petrifilm LAB Count Plates can simplify this testing process for food companies.
Kamoun, M; Ammar, H; Théwis, A; Beckers, Y; France, J; López, S
2014-11-01
The use of stable (15)N as a marker to determine microbial contamination in nylon bag incubation residues to estimate protein degradability was investigated. Three methods using (15)N were compared: (15)N-labeled forage (dilution method, LF), (15)N enrichment of rumen solids-associated bacteria (SAB), and (15)N enrichment of rumen liquid-associated bacteria (LAB). Herbage from forages differing in protein and fiber contents (early-cut Italian ryegrass, late-cut Italian ryegrass, and red clover) were freeze-dried and ground and then incubated in situ in the rumen of 3 steers for 3, 6, 12, 24, and 48 h using the nylon bag technique. The (15)N-labeled forages were obtained by fertilizing the plots where herbage was grown with (15)NH4 (15)NO3. Unlabeled forages (obtained from plots fertilized with NH4NO3) were incubated at the same time that ((15)NH4)2SO4 was continuously infused into the rumen of the steers, and then pellets of labeled SAB and LAB were isolated by differential centrifugation of samples of ruminal contents. The proportion of bacterial N in the incubation residues increased from 0.09 and 0.45 g bacterial N/g total N at 3 h of incubation to 0.37 and 0.85 g bacterial N/g total N at 48 h of incubation for early-cut and late-cut ryegrass, respectively. There were differences (P < 0.001) between uncorrected N degradability values and those corrected for microbial contamination with all of the methods. Apparent N degradability of the low-N, high-fiber forage (late-cut ryegrass) was 0.51, whereas the corrected values were 0.85, 0.84, and 0.77 for the LF, SAB, and LAB methods, respectively. With early-cut ryegrass and red clover, the differences between uncorrected and corrected values ranged between 6% and 13%, with small differences among the labeling methods. Generally, methods using labeled forage or labeled SAB and LAB provided similar corrected degradability values. The accuracy in estimating the extent of degradation of protein in the rumen from in situ disappearance curves is improved when values are corrected for microbial contamination of the bag residue.
NASA Astrophysics Data System (ADS)
Mohottala, Hashini
2014-03-01
The general student population enrolled in any college level class is highly diverse. An increasing number of ``nontraditional'' students return to college and most of these students follow distance learning degree programs while engaging in their other commitments, work and family. However, those students tend to avoid taking science courses with labs, mostly because of the incapability of remotely completing the lab components in such courses. In order to address this issue, we have come across a method where introductory level physics labs can be taught remotely. In this process a lab kit with the critical lab components that can be easily accessible are conveniently packed into a box and distributed among students at the beginning of the semester. Once the students are given the apparatus they perform the experiments at home and gather data All communications with reference to the lab was done through an interactive user-friendly webpage - Wikispaces (WikiS). Students who create pages on WikiS can submit their lab write-ups, embed videos of the experiments they perform, post pictures and direct questions to the lab instructor. The students who are enrolled in the same lab can interact with each other through WikiS to discuss labs and even get assistance.
Lavagnolo, Maria Cristina; Girotto, Francesca; Hirata, Osamu; Cossu, Raffaello
2017-08-01
An overall interaction is manifested between wastewater and solid waste management schemes. At the Laboratory of Environmental Engineering (LISA) of the University of Padova, Italy, the scientific and technical implications of putting into practice a decentralized waste and wastewater treatment based on the separation of grey water, brown water (BW - faecal matter) and yellow water (YW - urine) are currently undergoing investigation in the Aquanova Project. An additional aim of this concept is the source segregation of kitchen waste (KW) for subsequent anaerobic co-digestion with BW. To determine an optimal mixing ratio and temperature for use in the treatment of KW, BW, and eventually YW, by means of anaerobic digestion, a series of lab-scale batch tests were performed. Organic mixtures of KW and BW performed much better (max. 520mlCH 4 /gVS) in terms of methane yields than the individual substrates alone (max. 220mlCH 4 /gVS). A small concentration of urine proved to have a positive effect on anaerobic digestion performance, possibly due to the presence of micronutrients in YW. When considering high YW concentrations in the anaerobically digested mixtures, no ammonia inhibition was observed until a 30% and 10% YW content was added under mesophilic and thermophilic conditions, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.
Nylon and teflon scribe effect on NBR to Chemlok 233 and NBR to NBR bond interfaces
NASA Technical Reports Server (NTRS)
Jensen, S. K.
1990-01-01
A study was requested by Manufacturing Engineering to determine what effects marking with nylon (6/6) and Teflon scribes may have on subsequent bonding. Witness panel bond specimens were fabricated by the development lab to test both acrylonitrile butadiene rubber (NBR) to Chemlok and NBR to NBR after controlled exposure. The nylon rod used as a scribe tool demonstrates virtually no bond deterioration when used to scribe lines on either the Chemlok to NBR surfaces or the NBR to NBR interface. Lab test results indicate that the nylon rod-exposed samples produce tensile and peel values very similar to the control samples and the Teflon exposed samples produce tensile and peel values much lower than the control samples. Visual observation of the failure surfaces of the tested samples shows that Teflon scribing produces an obvious contamination to the surface and the nylon produces no effect. Photographs of test samples are provided. It is concluded that Teflon stock used as a scribe tool on a Chemlok 233 to NBR surface or an NBR to NBR surface has a detrimental effect on the bond integrity on either of these bond interfaces. Therefore, it is recommended that the nylon rod continue to be used where a scribe line is required in the redesigned solid rocket motor segment insulation layup operations. The use of Teflon scribes should not be considered.
Oh, Jin-Gyo; Seong, Jihyun; Han, Sunmi; Heo, Tae-Hwe
2018-05-17
Immunogenicity is a major concern in the use of biological drugs. In particular, antibody-mediated pure red cell aplasia (PRCA) is a rare condition that is caused by administration of recombinant erythropoietin. There are numerous assay platforms for detect EPO anti-drug antibody (ADA), and most have appropriate assay sensitivity, but in need of improvement in terms of assay turnaround time and user accessibility. Here, the new method was developed based on lab-on-a-chip technology and bridging ELISA. The FREND™ Cartridge is equipped with a microfluidic lateral flow channel, enabling easy, fast and accurate immunoassays with small sample volumes. Biotinylated EPO was immobilized on the avidin-coated solid phase of the test zone in the FREND™ cartridge. Initially, ADA in the serum sample binds to the detector conjugate (EPO-HRP-anti HRP antibody-FL bead) in the conjugation zone, and it flows into the test zone prepared with capture complex (avidin-biotinylated EPO). Unbound detector complexes are captured in the reference zone. The FREND™ system detects and quantifies the fluorescence signals in each zone and then calculates the concentration of EPO ADA in the sample. The FREND™ EPO ADA kit may be useful in local clinics as a rapid method for monitoring patients administered recombinant erythropoietin. Copyright © 2018 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Ballesteros, Erik Nicholas
2014-01-01
Understanding the surface and atmosphere of Mars is critical to current and future development of exploration systems. Dealing with the Martian regolith-the top layer of soil-remains a significant challenge, and much research is still needed. Addressing this need, the Cryogenics Test Lab and Granular Mechanics and Regolith Operations Lab at NASA's Kennedy Space Center are partnering to develop an apparatus that utilizes simulated Martian regolith in an analogous atmospheric environment to gather data about how the material behaves when exposed to water vapor. Martian surface temperatures range from 128 K (-145 C) to 308 K (35 C), and the average pressure is approximately 4.5 Torr; which presents an environment where water can potentially exist in vapor, solid or liquid form. And based on prior Mars missions such as the Phoenix Lander, it is known that water-ice exists just below the surface. This test apparatus will attempt to recreate the conditions that contributed to the Martian ice deposits by exposing a sample to water vapor at low pressure and temperature; thereby forming ice inside the simulant via diffusion. From this, we can better understand the properties and behavior of the regolith, and have more knowledge concerning its ability to store water-and subsequently, how to dig up and extract that water-which will be crucial to sample gathering when the first manned Mars mission takes place.
NASA Astrophysics Data System (ADS)
Selker, J. S.; Roques, C.; Higgins, C. W.; Good, S. P.; Hut, R.; Selker, A.
2015-12-01
The confluence of 3-Dimensional printing, low-cost solid-state-sensors, low-cost, low-power digital controllers (e.g., Arduinos); and open-source publishing (e.g., Github) is poised to transform environmental sensing. The Open-Source Published Environmental Sensing (OPENS) laboratory has launched and is available for all to use. OPENS combines cutting edge technologies and makes them available to the global environmental sensing community. OPENS includes a Maker lab space where people may collaborate in person or virtually via on-line forum for the publication and discussion of environmental sensing technology (Corvallis, Oregon, USA, please feel free to request a free reservation for space and equipment use). The physical lab houses a test-bed for sensors, as well as a complete classical machine shop, 3-D printers, electronics development benches, and workstations for code development. OPENS will provide a web-based formal publishing framework wherein global students and scientists can peer-review publish (with DOI) novel and evolutionary advancements in environmental sensor systems. This curated and peer-reviewed digital collection will include complete sets of "printable" parts and operating computer code for sensing systems. The physical lab will include all of the machines required to produce these sensing systems. These tools can be addressed in person or virtually, creating a truly global venue for advancement in monitoring earth's environment and agricultural systems. In this talk we will present an example of the process of design and publication the design and data from the OPENS-Permeameter. The publication includes 3-D printing code, Arduino (or other control/logging platform) operational code; sample data sets, and a full discussion of the design set in the scientific context of previous related devices. Editors for the peer-review process are currently sought - contact John.Selker@Oregonstate.edu or Clement.Roques@Oregonstate.edu.
De Vita, R; Anghinolfi, M; Burkert, V D; Dodge, G E; Minehart, R; Taiuti, M; Weller, H; Adams, G; Amaryan, M J; Anciant, E; Armstrong, D S; Asavapibhop, B; Asryan, G; Audit, G; Auger, T; Avakian, H; Bagdasaryan, H; Ball, J P; Barrow, S; Battaglieri, M; Beard, K; Bektasoglu, M; Bianchi, N; Biselli, A S; Boiarinov, S; Bonner, B E; Bosted, P; Bouchigny, S; Branford, D; Brooks, W K; Bueltmann, S; Calarco, J R; Capitani, G P; Carman, D S; Carnahan, B; Cazes, A; Ciciani, L; Cole, P L; Coleman, A; Connelly, J; Cords, D; Corvisiero, P; Crabb, D; Crannell, H; Cummings, J P; De Sanctis, E; Degtyarenko, P V; Demirchyan, R; Denizli, H; Dennis, L; Dharmawardane, K V; Dhuga, K S; Djalali, C; Doughty, D; Dragovitsch, P; Dugger, M; Dytman, S; Eckhause, M; Egiyan, H; Egiyan, K S; Elouadrhiri, L; Empl, A; Farhi, L; Fatemi, R; Feuerbach, R J; Ficenec, J; Forest, T A; Frolov, V; Funsten, H; Gaff, S J; Gai, M; Garçon, M; Gavalian, G; Gilad, S; Gilfoyle, G P; Giovanetti, K L; Girard, P; Golovatch, E; Griffioen, K; Guidal, M; Guillo, M; Gyurjyan, V; Hadjidakis, C; Hancock, D; Hardie, J; Heddle, D; Heimberg, P; Hersman, F W; Hicks, K; Hicks, R S; Holtrop, M; Hu, J; Hyde-Wright, C E; Ishkanov, B S; Ito, M M; Jenkins, D; Joo, K; Kelley, J H; Kellie, J D; Khandaker, M; Kim, K Y; Kim, K; Kim, W; Klein, A; Klein, F J; Klusman, M; Kossov, M; Kramer, L H; Kuang, Y; Kuhn, S E; Lachniet, J; Laget, J M; Lawrence, D; Li, Ji; Livingston, K; Longhi, A; Loukachine, K; Lucas, M; Major, W; Manak, J J; Marchand, C; McAleer, S; McCarthy, J; McNabb, J W C; Mecking, B A; Mestayer, M D; Meyer, C A; Mikhailov, K; Mirazita, M; Miskimen, R; Mokeev, V; Muccifora, V; Mueller, J; Mutchler, G S; Napolitano, J; Nelson, S O; Niculescu, G; Niculescu, I; Niczyporuk, B B; Niyazov, R A; Opper, A K; O'Rielly, G V; Osipenko, M; Park, K; Pasyuk, E; Peterson, G; Philips, S A; Pivnyuk, N; Pocanic, D; Pogorelko, O; Polli, E; Pozdniakov, S; Preedom, B M; Price, J W; Prok, Y; Protopopescu, D; Qin, L M; Raue, B A; Reolon, A R; Riccardi, G; Ricco, G; Ripani, M; Ritchie, B G; Rock, S; Ronchetti, F; Rossi, P; Rowntree, D; Rubin, P D; Sabatié, F; Sabourov, K; Salgado, C; Sapunenko, V; Sargsyan, M; Schumacher, R A; Serov, V S; Shafi, A; Sharabian, Y G; Shaw, J; Skabelin, A V; Smith, E S; Smith, T; Smith, L C; Sober, D I; Sorrell, L; Spraker, M; Stavinsky, A; Stepanyan, S; Stoler, P; Strakovsky, I I; Taylor, S; Tedeschi, D J; Thompson, R; Todor, L; Ungaro, M; Vineyard, M F; Vlassov, A V; Wang, K; Weinstein, L B; Weisberg, A; Weygand, D P; Whisnant, C S; Wolin, E; Yegneswaran, A; Yun, J; Zhang, B; Zhao, J; Zhou, Z
2002-02-25
The double spin asymmetry in the (-->)e(-->)p --> e(prime)pi(+)n reaction has been measured for the first time in the resonance region for four-momentum transfer Q2 = 0.35-1.5 GeV(2). Data were taken at Jefferson Lab with the CLAS detector using a 2.6 GeV polarized electron beam incident on a polarized solid NH3 target. Comparison with predictions of phenomenological models shows strong sensitivity to resonance contributions. Helicity-1/2 transitions are found to be dominant in the second and third resonance regions. The measured asymmetry is consistent with a faster rise with Q(2) of the helicity asymmetry A1 for the F(15)(1680) resonance than expected from the analysis of the unpolarized data.
Sustainable wastewater treatment of temporary events: the Dranouter Music Festival case study.
Van Hulle, S W H; Audenaert, W; Decostere, B; Hogie, J; Dejans, P
2008-01-01
Music festivals and other temporary events, such as bicycle races, lay a heavy burden on the surrounding environment. Treatment of the wastewater originating from such events is necessary if no municipal treatment plant is available. This study demonstrated that activated carbon is a performant technique for the treatment of wastewaters originating from these temporary events. Freundlich isotherms and maximum operational linear velocity (6 m/h) were determined on a lab-scale set-up. A pilot-scale set up was used to treat part (5%) of the total volume of the Dranouter Music Festival shower wastewater. On average 90% removal of COD and suspended solids concentration was obtained. Application of the activated carbon filter resulted in the fact that the local discharge limits were met without operational problems. IWA Publishing 2008.
US EPA's Ecological Risk Assessment Support Center ...
BackgroundThe ERASC provides technical information and addresses scientific questions of concern or interest on topics relevant to ecological risk assessment at hazardous waste sites for EPA's Office of Solid Waste and Emergency Response (OSWER) personnel and the Office of Resource Conservation and Recovery (ORCR) staff. Requests are channeled to ERASC through the Ecological Risk Assessment Forum (ERAF). To assess emerging and complex scientific issues that require expert judgment, the ERASC relies on the expertise of scientists and engineers located throughout EPA's Office of Research and Development (ORD) labs and centers.ResponseERASC develops responses that reflect the state of the science for ecological risk assessment and also provides a communication point for the distribution of the responses to other interested parties. For further information, contact Ecology_ERASC@epa.gov or call 513-569-7940.
Characterization of quantum well laser diodes for application within the AMRDEC HWIL facilities
NASA Astrophysics Data System (ADS)
Saylor, Daniel A.; Bender, Matt; Cantey, Thomas M.; Beasley, D. B.; Buford, Jim A.
2004-08-01
The U.S. Army's Research, Development, and Engineering Command's (RDECOM) Aviation and Missile Research, Development, and Engineering Center (AMRDEC) provides Hardware-in-the-Loop (HWIL) test support to numerous tactical and theatre missile programs. Critical to the successful execution of these tests is the state-of-the-art technologies employed in the visible and infrared scene projector systems. This paper describes the results of characterizations tests performed on new mid-wave infrared (MWIR) quantum well laser diodes recently provided to AMRDEC by the Naval Research Labs and Sarnoff Industries. These lasers provide a +10X imrovement in MWIR output over the previous technology of lead-salt laser diodes. Performance data on output power, linearity, and solid-angle coverage are presented. A discussion of the laser packages is also provided.
The CARIBU EBIS control and synchronization system
NASA Astrophysics Data System (ADS)
Dickerson, Clayton; Peters, Christopher
2015-01-01
The Californium Rare Isotope Breeder Upgrade (CARIBU) Electron Beam Ion Source (EBIS) charge breeder has been built and tested. The bases of the CARIBU EBIS electrical system are four voltage platforms on which both DC and pulsed high voltage outputs are controlled. The high voltage output pulses are created with either a combination of a function generator and a high voltage amplifier, or two high voltage DC power supplies and a high voltage solid state switch. Proper synchronization of the pulsed voltages, fundamental to optimizing the charge breeding performance, is achieved with triggering from a digital delay pulse generator. The control system is based on National Instruments realtime controllers and LabVIEW software implementing Functional Global Variables (FGV) to store and access instrument parameters. Fiber optic converters enable network communication and triggering across the platforms.
Tempest in a sugar-coated lab vial.
Dragun, Duska; Philippe, Aurélie
2018-06-23
Angiotensin II type 1 receptor (AT 1 R) is a classical G-protein-coupled-receptor (GPCR) displaying complex structure consisting of 7-transmembrane helices connected by intracellular and extracellular loops. Beside Angiotensin II binding within transmembrane sites and mechanically induced ligand free activation, AT 1 R can be also activated by agonistic autoantibodies (AT 1 R-Ab) recognizing conformational epitopes contained in the second extracellular loop. Direct pathophysiologic involvement of AT 1 R-Abs is well established in several autoimmune contexts and organ transplantation (1). A commercially available sandwich ELISA appreciating native receptor conformation relies on cell membrane AT 1 R extracts from human AT 1 R overexpressing Chinese hamster ovary (CHO) cells as a solid phase. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Berkeley Lab Berkeley Lab A-Z Index Phone Book Jobs Search DOE Help Berkeley Lab Training Welcome Welcome to Berkeley Lab Training! Login to access your LBNL Training Profile. This provides quick access to all of the courses you need. Look below, to learn about different types of training available at
Berkeley Lab Scientist Named MacArthur "Genius" Fellow for Audio
Preservation Research | Berkeley Lab Berkeley Lab A-Z Index Directory Submit Web People Navigation Berkeley Lab Search Submit Web People Close About the Lab Leadership/Organization Calendar News to digitally recover a 128-year-old recording of Alexander Graham Bell's voice, enabling people to
Stress Physiology of Lactic Acid Bacteria
Papadimitriou, Konstantinos; Alegría, Ángel; Bron, Peter A.; de Angelis, Maria; Gobbetti, Marco; Kleerebezem, Michiel; Lemos, José A.; Linares, Daniel M.; Ross, Paul; Stanton, Catherine; Turroni, Francesca; van Sinderen, Douwe; Varmanen, Pekka; Ventura, Marco; Zúñiga, Manuel; Tsakalidou, Effie
2016-01-01
SUMMARY Lactic acid bacteria (LAB) are important starter, commensal, or pathogenic microorganisms. The stress physiology of LAB has been studied in depth for over 2 decades, fueled mostly by the technological implications of LAB robustness in the food industry. Survival of probiotic LAB in the host and the potential relatedness of LAB virulence to their stress resilience have intensified interest in the field. Thus, a wealth of information concerning stress responses exists today for strains as diverse as starter (e.g., Lactococcus lactis), probiotic (e.g., several Lactobacillus spp.), and pathogenic (e.g., Enterococcus and Streptococcus spp.) LAB. Here we present the state of the art for LAB stress behavior. We describe the multitude of stresses that LAB are confronted with, and we present the experimental context used to study the stress responses of LAB, focusing on adaptation, habituation, and cross-protection as well as on self-induced multistress resistance in stationary phase, biofilms, and dormancy. We also consider stress responses at the population and single-cell levels. Subsequently, we concentrate on the stress defense mechanisms that have been reported to date, grouping them according to their direct participation in preserving cell energy, defending macromolecules, and protecting the cell envelope. Stress-induced responses of probiotic LAB and commensal/pathogenic LAB are highlighted separately due to the complexity of the peculiar multistress conditions to which these bacteria are subjected in their hosts. Induction of prophages under environmental stresses is then discussed. Finally, we present systems-based strategies to characterize the “stressome” of LAB and to engineer new food-related and probiotic LAB with improved stress tolerance. PMID:27466284
2007-03-01
Congress Facility 7366 30251 Hazardous Material Storage Shed 432 20447 Aircraft Research Lab 1630 20449 Aircraft Research Lab 2480 34042 Reserve Forces...Congress Facility 0.566 20055 Engineering Admin. Building 0.578 20449 Aircraft Research Lab 0.595 20447 Aircraft Research Lab 0.605 20464...0.525 $39.00 0.01346 20447 Aircraft Research Lab 0.605 $59.50 0.01017 20449 Aircraft Research Lab 0.595 $62.40 0.00954 20464 Area B Gas Station
Love the Lab, Hate the Lab Report?
ERIC Educational Resources Information Center
Bjorn, Genevive
2018-01-01
In the author's large, urban high school, enrollment in a laboratory science is mandatory. While the student participation rate for lab activities is over 98%, the turn-in rate for traditional lab reports averages just 35% to 85%. Those students who don't produce a lab report miss a critical opportunity to improve their skills in scientific…
Assessing Usage and Maximizing Finance Lab Impact: A Case Exploration
ERIC Educational Resources Information Center
Noguera, Magdy; Budden, Michael Craig; Silva, Alberto
2011-01-01
This paper reports the results of a survey conducted to assess students' usage and perceptions of a finance lab. Finance labs differ from simple computer labs as they typically contain data boards, streaming market quotes, terminals and software that allow for real-time financial analyses. Despite the fact that such labs represent significant and…
Planning a Computer Lab: Considerations To Ensure Success.
ERIC Educational Resources Information Center
IALL Journal of Language Learning Technologies, 1994
1994-01-01
Presents points to consider when organizing a computer laboratory. These include the lab's overall objectives and how best to meet them; what type of students will use the lab; where the lab will be located; and what software and hardware can best meet the lab's overall objectives, population, and location requirements. Other factors include time,…
Design of Inquiry-Oriented Science Labs: Impacts on Students' Attitudes
ERIC Educational Resources Information Center
Baseya, J. M.; Francis, C. D.
2011-01-01
Background: Changes in lab style can lead to differences in learning. Two inquiry-oriented lab styles are guided inquiry (GI) and problem-based (PB). Students' attitudes towards lab are important to consider when choosing between GI and PB styles during curriculum design. Purpose: We examined the degree to which lab experiences are explained by a…
Microsoft Licenses Berkeley Lab's Home Energy Saver Code for Its Energy
-based tool for calculating energy use in residential buildings. About one million people visit the Home Management Software | Berkeley Lab Berkeley Lab A-Z Index Directory Submit Web People Navigation Berkeley Lab Search Submit Web People Close About the Lab Leadership/Organization Calendar News
Introductory labs; what they don't, should, and can teach (and why)
NASA Astrophysics Data System (ADS)
Wieman, Carl
2016-03-01
Introductory physics labs are widely used and expensive. They have a wide variety of potential learning goals, but these are seldom specified and less often measured if they are achieved. We cover three different research projects on introductory labs: 1) We have done cognitive task analyses of both experimental research in physics and instructional labs. The striking differences explain much of the unhappiness expressed by students with labs: 2) We have measured the effectiveness of two introductory physics lab courses specifically intended to teach the physics content covered in standard introductory courses on mechanics and E & M. As measured by course exams, the benefit is 0 +/-2% for both. 3) We show how it is possible to use lab courses to teach students to correctly evaluate physical models with uncertain data. Such quantitative critical thinking is an important skill that is not learned in typical lab courses, but is well learned by our modified lab instruction.
Stress Physiology of Lactic Acid Bacteria.
Papadimitriou, Konstantinos; Alegría, Ángel; Bron, Peter A; de Angelis, Maria; Gobbetti, Marco; Kleerebezem, Michiel; Lemos, José A; Linares, Daniel M; Ross, Paul; Stanton, Catherine; Turroni, Francesca; van Sinderen, Douwe; Varmanen, Pekka; Ventura, Marco; Zúñiga, Manuel; Tsakalidou, Effie; Kok, Jan
2016-09-01
Lactic acid bacteria (LAB) are important starter, commensal, or pathogenic microorganisms. The stress physiology of LAB has been studied in depth for over 2 decades, fueled mostly by the technological implications of LAB robustness in the food industry. Survival of probiotic LAB in the host and the potential relatedness of LAB virulence to their stress resilience have intensified interest in the field. Thus, a wealth of information concerning stress responses exists today for strains as diverse as starter (e.g., Lactococcus lactis), probiotic (e.g., several Lactobacillus spp.), and pathogenic (e.g., Enterococcus and Streptococcus spp.) LAB. Here we present the state of the art for LAB stress behavior. We describe the multitude of stresses that LAB are confronted with, and we present the experimental context used to study the stress responses of LAB, focusing on adaptation, habituation, and cross-protection as well as on self-induced multistress resistance in stationary phase, biofilms, and dormancy. We also consider stress responses at the population and single-cell levels. Subsequently, we concentrate on the stress defense mechanisms that have been reported to date, grouping them according to their direct participation in preserving cell energy, defending macromolecules, and protecting the cell envelope. Stress-induced responses of probiotic LAB and commensal/pathogenic LAB are highlighted separately due to the complexity of the peculiar multistress conditions to which these bacteria are subjected in their hosts. Induction of prophages under environmental stresses is then discussed. Finally, we present systems-based strategies to characterize the "stressome" of LAB and to engineer new food-related and probiotic LAB with improved stress tolerance. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Designing virtual science labs for the Islamic Academy of Delaware
NASA Astrophysics Data System (ADS)
AlZahrani, Nada Saeed
Science education is a basic part of the curriculum in modern day classrooms. Instructional approaches to science education can take many forms but hands-on application of theory via science laboratory activities for the learner is common. Not all schools have the resources to provide the laboratory environment necessary for hands-on application of science theory. Some settings rely on technology to provide a virtual laboratory experience instead. The Islamic Academy of Delaware (IAD), a typical community-based organization, was formed to support and meet the essential needs of the Muslim community of Delaware. IAD provides science education as part of the overall curriculum, but cannot provide laboratory activities as part of the science program. Virtual science labs may be a successful model for students at IAD. This study was conducted to investigate the potential of implementing virtual science labs at IAD and to develop an implementation plan for integrating the virtual labs. The literature has shown us that the lab experience is a valuable part of the science curriculum (NBPTS, 2013, Wolf, 2010, National Research Council, 1997 & 2012). The National Research Council (2012) stressed the inclusion of laboratory investigations in the science curriculum. The literature also supports the use of virtual labs as an effective substitute for classroom labs (Babateen, 2011; National Science Teachers Association, 2008). Pyatt and Simms (2011) found evidence that virtual labs were as good, if not better than physical lab experiences in some respects. Although not identical in experience to a live lab, the virtual lab has been shown to provide the student with an effective laboratory experience in situations where the live lab is not possible. The results of the IAD teacher interviews indicate that the teachers are well-prepared for, and supportive of, the implementation of virtual labs to improve the science education curriculum. The investigator believes that with the support of the literature and the readiness of the IAD administration and teachers, a recommendation to implement virtual labs into the curriculum can be made.
ERIC Educational Resources Information Center
Marshall, Pamela A.
2007-01-01
In our Fundamentals of Genetics lab, students perform a wide variety of labs to reinforce and extend the topics covered in lecture. I developed an active-learning lab to augment the lecture topic of mutagenesis. In this lab exercise, students determine if a compound they bring from home is a mutagen. Students are required to read extensive…
NASA Astrophysics Data System (ADS)
Cobb, Bethany E.
2018-01-01
Since 2013, the Physics Department at GWU has used student-centered active learning in the introductory astronomy course “Introduction to the Cosmos.” Class time is spent in groups on questions, math problems, and hands-on activities, with multiple instructors circulating to answer questions and engage with the students. The students have responded positively to this active-learning. Unfortunately, in transitioning to active-learning there was no time to rewrite the labs. Very quickly, the contrast between the dynamic classroom and the traditional labs became apparent. The labs were almost uniformly “cookie-cutter” in that the procedure and analysis were specified step-by-step and there was just one right answer. Students rightly criticized the labs for lacking a clear purpose and including busy-work. Furthermore, this class fulfills the GWU scientific reasoning general education requirement and thus includes learning objectives related to understanding the scientific method, testing hypotheses with data, and considering uncertainty – but the traditional labs did not require these skills. I set out to rejuvenate the lab sequence by writing new inquiry labs based on both topic-specific and scientific reasoning learning objectives. While inquiry labs can be challenging for the students, as they require active thinking and creativity, these labs engage the students more thoroughly in the scientific process. In these new labs, whenever possible, I include real astronomical data and ask the students to use digital tools (SDSS SkyServer, SOHO archive) as if they are real astronomers. To allow students to easily plot, manipulate and analyze data, I built “smart” Excel files using formulas, dropdown menus and macros. The labs are now much more authentic and thought-provoking. Whenever possible, students independently develop questions, hypotheses, and procedures and the scientific method is “scaffolded” over the semester by providing more guidance in the early labs and more independence later on. Finally, in every lab, students must identify and reflect on sources of error. These labs are more challenging for the instructors to run and to grade, but they are much more satisfying when it comes to student learning.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jones, Eric D.
1999-06-17
In the world of computer-based data acquisition and control, the graphical interface program LabVIEW from National Instruments is so ubiquitous that in many ways it has almost become the laboratory standard. To date, there have been approximately fifteen books concerning LabVIEW, but Professor Essick's treatise takes on a completely different tack than all of the previous discussions. In the more standard treatments of the ways and wherefores of LabVIEW such as LabVIEW Graphical Programming: Practical Applications in Instrumentation and Control by Gary W. Johnson (McGraw Hill, NY 1997), the emphasis has been instructing the reader how to program LabVIEW tomore » create a Virtual Instrument (VI) on the computer for interfacing to a particular instruments. LabVIEW is written in G a graphical programming language developed by National Instruments. In the past the emphasis has been on training the experimenter to learn G . Without going into details here, G incorporates the usual loops, arithmetic expressions, etc., found in many programming languages, but in an icon (graphical) environment. The net result being that LabVIEW contains all of the standard methods needed for interfacing to instruments, data acquisition, data analysis, graphics, and also methodology to incorporate programs written in other languages into LabVIEW. Historically, according to Professor Essick, he developed a series of experiments for an upper division laboratory course for computer-based instrumentation. His observation was that while many students had the necessary background in computer programming languages, there were students who had virtually no concept about writing a computer program let alone a computer- based interfacing program. Thus the beginnings of a concept for not only teaching computer- based instrumentation techniques, but aiso a method for the beginner to experience writing a com- puter program. Professor Essick saw LabVIEW as the perfect environment in which to teach computer-based research skills. With this goal in mind, he has succeeded admirably. Advanced LabVIEW Labs presents a series of chapters devoted to not only introducing the reader to LabVIEW, but also to the concepts necessary for writing a successful computer pro- gram. Each chapter is an assignment for the student and is suitable for a ten week course. The first topic introduces the while loop and waveform chart VI'S. After learning how to launch LabVIEW, the student then leans how to use LabVIEW functions such as sine and cosine. The beauty of thk and subsequent chapters, the student is introduced immediately to computer-based instruction by learning how to display the results in graph form on the screen. At each point along the way, the student is not only introduced to another LabVIEW operation, but also to such subjects as spread sheets for data storage, numerical integration, Fourier transformations', curve fitting algorithms, etc. The last few chapters conclude with the purpose of the learning module, and that is, com- puter-based instrumentation. Computer-based laboratory projects such as analog-to-digital con- version, digitizing oscilloscopes treated. Advanced Lab VIEW Labs finishes with a treatment on GPIB interfacing and finally, the student is asked to create an operating VI for temperature con- trol. This is an excellent text, not only as an treatise on LabVIEW but also as an introduction to computer programming logic. All programmers, who are struggling to not only learning how interface computers to instruments, but also trying understand top down programming and other programming language techniques, should add Advanced Lab-VIEW Labs to their computer library.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jones, Eric D.
1999-06-17
In the world of computer-based data acquisition and control, the graphical interface program LabVIEW from National Instruments is so ubiquitous that in many ways it has almost become the laboratory standard. To date, there have been approximately fifteen books concerning LabVIEW, but Professor Essick's treatise takes on a completely different tack than all of the previous discussions. In the more standard treatments of the ways and wherefores of LabVIEW such as LabVIEW Graphical Programming: Practical Applications in Instrumentation and Control by Gary W. Johnson (McGraw Hill, NY 1997), the emphasis has been instructing the reader how to program LabVIEW tomore » create a Virtual Instrument (VI) on the computer for interfacing to a particular instruments. LabVIEW is written in "G" a graphical programming language developed by National Instruments. In the past the emphasis has been on training the experimenter to learn "G". Without going into details here, "G" incorporates the usual loops, arithmetic expressions, etc., found in many programming languages, but in an icon (graphical) environment. The net result being that LabVIEW contains all of the standard methods needed for interfacing to instruments, data acquisition, data analysis, graphics, and also methodology to incorporate programs written in other languages into LabVIEW. Historically, according to Professor Essick, he developed a series of experiments for an upper division laboratory course for computer-based instrumentation. His observation was that while many students had the necessary background in computer programming languages, there were students who had virtually no concept about writing a computer program let alone a computer- based interfacing program. Thus the beginnings of a concept for not only teaching computer- based instrumentation techniques, but aiso a method for the beginner to experience writing a com- puter program. Professor Essick saw LabVIEW as the "perfect environment in which to teach computer-based research skills." With this goal in mind, he has succeeded admirably. Advanced LabVIEW Labs presents a series of chapters devoted to not only introducing the reader to LabVIEW, but also to the concepts necessary for writing a successful computer pro- gram. Each chapter is an assignment for the student and is suitable for a ten week course. The first topic introduces the while loop and waveform chart VI'S. After learning how to launch LabVIEW, the student then leans how to use LabVIEW functions such as sine and cosine. The beauty of thk and subsequent chapters, the student is introduced immediately to computer-based instruction by learning how to display the results in graph form on the screen. At each point along the way, the student is not only introduced to another LabVIEW operation, but also to such subjects as spread sheets for data storage, numerical integration, Fourier transformations', curve fitting algorithms, etc. The last few chapters conclude with the purpose of the learning module, and that is, com- puter-based instrumentation. Computer-based laboratory projects such as analog-to-digital con- version, digitizing oscilloscopes treated. Advanced Lab VIEW Labs finishes with a treatment on GPIB interfacing and finally, the student is asked to create an operating VI for temperature con- trol. This is an excellent text, not only as an treatise on LabVIEW but also as an introduction to computer programming logic. All programmers, who are struggling to not only learning how interface computers to instruments, but also trying understand top down programming and other programming language techniques, should add Advanced Lab-VIEW Labs to their computer library.« less
Makransky, Guido; Thisgaard, Malene Warming; Gadegaard, Helen
2016-01-01
To investigate if a virtual laboratory simulation (vLAB) could be used to replace a face to face tutorial (demonstration) to prepare students for a laboratory exercise in microbiology. A total of 189 students who were participating in an undergraduate biology course were randomly selected into a vLAB or demonstration condition. In the vLAB condition students could use a vLAB at home to 'practice' streaking out bacteria on agar plates in a virtual environment. In the demonstration condition students were given a live demonstration from a lab tutor showing them how to streak out bacteria on agar plates. All students were blindly assessed on their ability to perform the streaking technique in the physical lab, and were administered a pre and post-test to determine their knowledge of microbiology, intrinsic motivation to study microbiology, and self-efficacy in the field of microbiology prior to, and after the experiment. The results showed that there were no significant differences between the two groups on their lab scores, and both groups had similar increases in knowledge of microbiology, intrinsic motivation to study microbiology, as well as self-efficacy in the field of microbiology. Our data show that vLABs function just as well as face to face tutorials in preparing students for a physical lab activity in microbiology. The results imply that vLABs could be used instead of face to face tutorials, and a combination of virtual and physical lab exercises could be the future of science education.
Cherenkov and scintillation light separation in organic liquid scintillators
NASA Astrophysics Data System (ADS)
Caravaca, J.; Descamps, F. B.; Land, B. J.; Yeh, M.; Orebi Gann, G. D.
2017-12-01
The CHErenkov/Scintillation Separation experiment (CHESS) has been used to demonstrate the separation of Cherenkov and scintillation light in both linear alkylbenzene (LAB) and LAB with 2 g/L of PPO as a fluor (LAB/PPO). This is the first successful demonstration of Cherenkov light detection from the more challenging LAB/PPO cocktail and improves on previous results for LAB. A time resolution of 338± 12 ps FWHM results in an efficiency for identifying Cherenkov photons in LAB/PPO of 70 ± 3 % and 63± 8% for time- and charge-based separation, respectively, with scintillation contamination of 36± 5% and 38± 4%. LAB/PPO data is consistent with a rise time of τ _r=0.72± 0.33 ns.
Inexpensive DAQ based physics labs
NASA Astrophysics Data System (ADS)
Lewis, Benjamin; Clark, Shane
2015-11-01
Quality Data Acquisition (DAQ) based physics labs can be designed using microcontrollers and very low cost sensors with minimal lab equipment. A prototype device with several sensors and documentation for a number of DAQ-based labs is showcased. The device connects to a computer through Bluetooth and uses a simple interface to control the DAQ and display real time graphs, storing the data in .txt and .xls formats. A full device including a larger number of sensors combined with software interface and detailed documentation would provide a high quality physics lab education for minimal cost, for instance in high schools lacking lab equipment or students taking online classes. An entire semester’s lab course could be conducted using a single device with a manufacturing cost of under $20.
ERIC Educational Resources Information Center
Emery, Dave
1996-01-01
Describes a lab involving a cloud formation activity that uses the constructivist learning model to get students more involved in creating the lab. Enables students to develop a greater understanding of the concepts involved and more interest in the lab's outcomes. (JRH)
NASA Astrophysics Data System (ADS)
Corsi, Gianluca
2011-12-01
Web-based technology has revolutionized the way education is delivered. Although the advantages of online learning appeal to large numbers of students, some concerns arise. One major concern in online science education is the value that participation in labs has on student performance. The purpose of this study was to assess the relationships between lab completion and student academic success as measured by test grades, scientific self-confidence, scientific skills, and concept mastery. A random sample of 114 volunteer undergraduate students, from an online Environmental Science program at the American Public University System, was tested. The study followed a quantitative, non-experimental research design. Paired sample t-tests were used for statistical comparison between pre-lab and post-lab test grades, two scientific skills quizzes, and two scientific self-confidence surveys administered at the beginning and at the end of the course. The results of the paired sample t-tests revealed statistically significant improvements on all post-lab test scores: Air Pollution lab, t(112) = 6.759, p < .001; Home Chemicals lab t(114) = 8.585, p < .001; Water Use lab, t(116) = 6.657, p < .001; Trees and Carbon lab, t(113) = 9.921, p < .001; Stratospheric Ozone lab, t(112) =12.974, p < .001; Renewable Energy lab, t(115) = 7.369, p < .001. The end of the course Scientific Skills quiz revealed statistically significant improvements, t(112) = 8.221, p < .001. The results of the two surveys showed a statistically significant improvement on student Scientific Self-Confidence because of lab completion, t(114) = 3.015, p < .05. Because age and gender were available, regression models were developed. The results indicated weak multiple correlation coefficients and were not statistically significant at alpha = .05. Evidence suggests that labs play a positive role in a student's academic success. It is recommended that lab experiences be included in all online Environmental Science programs, with emphasis on open-ended inquiries, and adoption of online tools to enhance hands-on experiences, such as virtual reality platforms and digital animations. Future research is encouraged to investigate possible correlations between socio-demographic attributes and academic success of students enrolled in online science programs in reference to lab completion.
Towards a Manifesto for Living Lab Co-creation
NASA Astrophysics Data System (ADS)
Følstad, Asbjørn; Brandtzæg, Petter Bae; Gulliksen, Jan; Börjeson, Mikael; Näkki, Pirjo
There is a growing interest in Living Labs for innovation and development in the field of information and communication technology. In particular there seem to be a tendency that current Living Labs aim to involve users for co-creative purposes. However, the current literature on Living Lab co-creation is severely limited. Therefore an Interact workshop is arranged as a first step towards a manifesto for Living Lab co-creation.
ERIC Educational Resources Information Center
Spiro, Mark D.; Knisely, Karin I.
2008-01-01
Inquiry-based labs have been shown to greatly increase student participation and learning within the biological sciences. One challenge is to develop effective lab exercises within the constraints of large introductory labs. We have designed a lab for first-year biology majors to address two primary goals: to provide effective learning of the…
Open web system of Virtual labs for nuclear and applied physics
NASA Astrophysics Data System (ADS)
Saldikov, I. S.; Afanasyev, V. V.; Petrov, V. I.; Ternovykh, M. Yu
2017-01-01
An example of virtual lab work on unique experimental equipment is presented. The virtual lab work is software based on a model of real equipment. Virtual labs can be used for educational process in nuclear safety and analysis field. As an example it includes the virtual lab called “Experimental determination of the material parameter depending on the pitch of a uranium-water lattice”. This paper included general description of this lab. A description of a database on the support of laboratory work on unique experimental equipment which is included this work, its concept development are also presented.
Cherenkov and scintillation light separation in organic liquid scintillators
Caravaca, J.; Descamps, F. B.; Land, B. J.; ...
2017-11-29
The CHErenkov/Scintillation Separation experiment (CHESS) has been used to demonstrate the separation of Cherenkov and scintillation light in both linear alkylbenzene (LAB) and LAB with 2 g/L of PPO as a fluor (LAB/PPO). This is the first successful demonstration of Cherenkov light detection from the more challenging LAB/PPO cocktail and improves on previous results for LAB. A time resolution of 338 ± 12 ps FWHM results in an efficiency for identifying Cherenkov photons in LAB/PPO of 70 ± 3 % and 63 ± 8 % for time- and charge-based separation, respectively, with scintillation contamination of 36 ± 5 % andmore » 38 ± 4 %. LAB/PPO data is consistent with a rise time of τ r = 0.72 ± 0.33 ns.« less
Cherenkov and scintillation light separation in organic liquid scintillators
DOE Office of Scientific and Technical Information (OSTI.GOV)
Caravaca, J.; Descamps, F. B.; Land, B. J.
The CHErenkov/Scintillation Separation experiment (CHESS) has been used to demonstrate the separation of Cherenkov and scintillation light in both linear alkylbenzene (LAB) and LAB with 2 g/L of PPO as a fluor (LAB/PPO). This is the first successful demonstration of Cherenkov light detection from the more challenging LAB/PPO cocktail and improves on previous results for LAB. A time resolution of 338 ± 12 ps FWHM results in an efficiency for identifying Cherenkov photons in LAB/PPO of 70 ± 3 % and 63 ± 8 % for time- and charge-based separation, respectively, with scintillation contamination of 36 ± 5 % andmore » 38 ± 4 %. LAB/PPO data is consistent with a rise time of τ r = 0.72 ± 0.33 ns.« less
Kariuki, Jacob K; Gona, Philimon; Leveille, Suzanne G; Stuart-Shor, Eileen M; Hayman, Laura L; Cromwell, Jerry
2018-06-01
The non-lab Framingham algorithm, which substitute body mass index for lipids in the laboratory based (lab-based) Framingham algorithm, has been validated among African Americans (AAs). However, its cost-effectiveness and economic tradeoffs have not been evaluated. This study examines the incremental cost-effectiveness ratio (ICER) of two cardiovascular disease (CVD) prevention programs guided by the non-lab versus lab-based Framingham algorithm. We simulated the World Health Organization CVD prevention guidelines on a cohort of 2690 AA participants in the Atherosclerosis Risk in Communities (ARIC) cohort. Costs were estimated using Medicare fee schedules (diagnostic tests, drugs & visits), Bureau of Labor Statistics (RN wages), and estimates for managing incident CVD events. Outcomes were assumed to be true positive cases detected at a data driven treatment threshold. Both algorithms had the best balance of sensitivity/specificity at the moderate risk threshold (>10% risk). Over 12years, 82% and 77% of 401 incident CVD events were accurately predicted via the non-lab and lab-based Framingham algorithms, respectively. There were 20 fewer false negative cases in the non-lab approach translating into over $900,000 in savings over 12years. The ICER was -$57,153 for every extra CVD event prevented when using the non-lab algorithm. The approach guided by the non-lab Framingham strategy dominated the lab-based approach with respect to both costs and predictive ability. Consequently, the non-lab Framingham algorithm could potentially provide a highly effective screening tool at lower cost to address the high burden of CVD especially among AA and in resource-constrained settings where lab tests are unavailable. Copyright © 2017 Elsevier Inc. All rights reserved.
An evaluation of two hands-on lab styles for plant biodiversity in undergraduate biology.
Basey, John M; Maines, Anastasia P; Francis, Clinton D; Melbourne, Brett
2014-01-01
We compared learning cycle and expository formats for teaching about plant biodiversity in an inquiry-oriented university biology lab class (n = 465). Both formats had preparatory lab activities, a hands-on lab, and a postlab with reflection and argumentation. Learning was assessed with a lab report, a practical quiz in lab, and a multiple-choice exam in the concurrent lecture. Attitudes toward biology and treatments were also assessed. We used linear mixed-effect models to determine impacts of lab style on lower-order cognition (LO) and higher-order cognition (HO) based on Bloom's taxonomy. Relative to the expository treatment, the learning cycle treatment had a positive effect on HO and a negative effect on LO included in lab reports; a positive effect on transfer of LO from the lab report to the quiz; negative impacts on LO quiz performance and on attitudes toward the lab; and a higher degree of perceived difficulty. The learning cycle treatment had no influence on transfer of HO from lab report to quiz or exam; quiz performance on HO questions; exam performance on LO and HO questions; and attitudes toward biology as a science. The importance of LO as a foundation for HO relative to these lab styles is addressed. © 2014 J. M. Basey et al. CBE—Life Sciences Education © 2014 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).
Algorithm to illustrate context using dynamic lighting effects
NASA Astrophysics Data System (ADS)
John, Roshy M.; Balasubramanian, T.
2007-09-01
With the invention of Ultra-Bright LED, solid state lighting has come to something which is much more efficient and energy saving when compared to conventional incandescent or fluorescent lighting. With the use of proper driver electronics now a days it is possible to install solid state lighting systems with the cost same as that of any other lighting technology. This paper is a part of the research project we are doing in our lab, which deals with using ultra bright LEDs of different colors for lighting applications. The driver electronics are made in such a way that, the color and brightness of the lights will change according to context. For instance, if one of the users is reading a story or listening to music in a Personal Computer or in a hand held device such as a PDA, the lighting systems and the HVAC (Heating Ventilation Air-conditioning) systems will change dramatically according to the content of the story or the music. The vulnerability of solid-state lighting helps to accomplish such an effect. Such a type of system will help the reader to feel the story mentally and physically as well. We developed complete driver electronics for the system using multiple microcomputers and a full software suite which uses complex algorithms to decode the context from text or music and synchronize it to lighting and HVAC information. The paper also presents some case-study statistics which shows the advantage of using the system to teach kindergarten children, deaf and dumb children and for language learning classes.
Complete nutrient recovery from source-separated urine by nitrification and distillation.
Udert, K M; Wächter, M
2012-02-01
In this study we present a method to recover all nutrients from source-separated urine in a dry solid by combining biological nitrification with distillation. In a first process step, a membrane-aerated biofilm reactor was operated stably for more than 12 months, producing a nutrient solution with a pH between 6.2 and 7.0 (depending on the pH set-point), and an ammonium to nitrate ratio between 0.87 and 1.15 gN gN(-1). The maximum nitrification rate was 1.8 ± 0.3 gN m(-2) d(-1). Process stability was achieved by controlling the pH via the influent. In the second process step, real nitrified urine and synthetic solutions were concentrated in lab-scale distillation reactors. All nutrients were recovered in a dry powder except for some ammonia (less than 3% of total nitrogen). We estimate that the primary energy demand for a simple nitrification/distillation process is four to five times higher than removing nitrogen and phosphorus in a conventional wastewater treatment plant and producing the equivalent amount of phosphorus and nitrogen fertilizers. However, the primary energy demand can be reduced to values very close to conventional treatment, if 80% of the water is removed with reverse osmosis and distillation is operated with vapor compression. The ammonium nitrate content of the solid residue is below the limit at which stringent EU safety regulations for fertilizers come into effect; nevertheless, we propose some additional process steps that will increase the thermal stability of the solid product. Copyright © 2011 Elsevier Ltd. All rights reserved.
The NSLS 100 element solid state array detector
Furenlid, L.R.; Kraner, H.W.; Rogers, L.C.; Cramer, S.P.; Stephani, D.; Beuttenmuller, R.H.; Beren, J.
2015-01-01
X-ray absorption studies of dilute samples require fluorescence detection techniques. Since signal-to-noise ratios are governed by the ratio of fluorescent to scattered photons counted by a detector, solid state detectors which can discriminate between fluorescence and scattered photons have become the instruments of choice for trace element measurements. Commercially available 13 element Ge array detectors permitting total count rates < 500000 counts per second are now in routine use. Since X-ray absorption beamlines at high brightness synchrotron sources can already illuminate most dilute samples with enough flux to saturate the current generation of solid state detectors, the development of next-generation instruments with significantly higher total count rates is essential. We present the design and current status of the 100 element Si array detector being developed in a collaboration between the NSLS and the Instrumentation Division at Brookhaven National Laboratory. The detecting array consists of a 10×10 matrix of 4 mm×4 mm elements laid out on a single piece of ultrahigh purity silicon mounted at the front end of a liquid nitrogen dewar assembly. A matrix of charge sensitive integrating preamplifiers feed signals to an array of shaping amplifiers, single channel analyzers, and scalers. An electronic switch, delay amplifier, linear gate, digital scope, peak sensing A/D converter, and histogramining memory module provide for complete diagnostics and channel calibration. The entire instrument is controlled by a LabView 2 application on a MacII ci; the software also provides full control over beamline hardware and performs the data collection. PMID:26722135
Li, Na; Gilpin, Christopher J; Taylor, Lynne S
2017-05-01
Miscibility is critical for amorphous solid dispersions (ASDs). Phase-separated ASDs are more prone to crystallization, and thus can lose their solubility advantage leading to product failure. Additionally, dissolution performance can be diminished as a result of phase separation in the ASD matrix. Water is known to induce phase separation during storage for some ASDs. However, the impact of water introduced during preparation has not been as thoroughly investigated to date. The purpose of this study was to develop a mechanistic understanding of the effect of water on the phase behavior and microstructure of ASDs. Evacetrapib and two polymers were selected as the model system. Atomic force microscopy coupled with Lorentz contact resonance, and transmission electron microscopy with energy dispersive X-ray spectroscopy were employed to evaluate the microstructure and composition of phase-separated ASDs. It was found that phase separation could be induced via two routes: solution-state phase separation during ASD formation caused by water absorption during film formation by a hydrophilic solvent, or solid-phase separation following exposure to high RH during storage. Water contents of as low as 2% in the organic solvent system used to dissolve the drug and polymer were found to result in phase separation in the resultant ASD film. These findings have profound implications on lab-scale ASD preparation and potentially also for industrial production. Additionally, these high-resolution imaging techniques combined with orthogonal analyses are powerful tools to visualize structural changes in ASDs, which in turn will enable better links to be made between ASD structure and performance.
NASA Technical Reports Server (NTRS)
Saha, Hrishikesh; Palmer, Timothy A.
1996-01-01
Virtual Reality Lab Assistant (VRLA) demonstration model is aligned for engineering and material science experiments to be performed by undergraduate and graduate students in the course as a pre-lab simulation experience. This will help students to get a preview of how to use the lab equipment and run experiments without using the lab hardware/software equipment. The quality of the time available for laboratory experiments can be significantly improved through the use of virtual reality technology.
Multi-User Facilities for Molecular Marine Biology and Biotechnology
1990-04-06
relatedness (or non-relatedness) of symbiotic zooxanthellae in corals. The DNA synthesizer is used to prepare universal primers for 18s r RNA. A...tunicates (Weissman lab) Robert Rowan - Zooxanthellae (Powers lab) Lani West - sponges/barnacles (Powers lab) Jeff Mitton - Mytilus (Powers lab) Kristi
Michel, Christiane Röckl; Standke, Gesche; Naef, Reto
2012-01-01
The Novartis School Lab (http://www.novartis.ch/schullabor) is an institution with an old tradition. The School Lab reaches about 5000 students through internal courses and an additional 5000 children at public science events where they can enjoy hands-on science in disciplines of biomedical research. The subjects range from chemistry, physics, molecular biology and genetics to toxicology and medical topics. The Novartis School Lab offers a variety of activities for youngsters aged 10-20 ranging from lab courses for school classes, continuing education for teachers and development of teaching kits, support for individual research projects to outreach for public science events. Innovation and adaptation to changes of current needs are essential aspects for the Novartis School Lab. Ongoing activities to shape the Novartis Biomedical Learning Lab include design of new teaching experiments, exploration into additional disciplines of biomedical science and the creation of a fascinating School Lab of the future.
Integrating Robotic Observatories into Astronomy Labs
NASA Astrophysics Data System (ADS)
Ruch, Gerald T.
2015-01-01
The University of St. Thomas (UST) and a consortium of five local schools is using the UST Robotic Observatory, housing a 17' telescope, to develop labs and image processing tools that allow easy integration of observational labs into existing introductory astronomy curriculum. Our lab design removes the burden of equipment ownership by sharing access to a common resource and removes the burden of data processing by automating processing tasks that are not relevant to the learning objectives.Each laboratory exercise takes place over two lab periods. During period one, students design and submit observation requests via the lab website. Between periods, the telescope automatically acquires the data and our image processing pipeline produces data ready for student analysis. During period two, the students retrieve their data from the website and perform the analysis. The first lab, 'Weighing Jupiter,' was successfully implemented at UST and several of our partner schools. We are currently developing a second lab to measure the age of and distance to a globular cluster.
An analysis of high school students' perceptions and academic performance in laboratory experiences
NASA Astrophysics Data System (ADS)
Mirchin, Robert Douglas
This research study is an investigation of student-laboratory (i.e., lab) learning based on students' perceptions of experiences using questionnaire data and evidence of their science-laboratory performance based on paper-and-pencil assessments using Maryland-mandated criteria, Montgomery County Public Schools (MCPS) criteria, and published laboratory questions. A 20-item questionnaire consisting of 18 Likert-scale items and 2 open-ended items that addressed what students liked most and least about lab was administered to students before labs were observed. A pre-test and post-test assessing laboratory achievement were administered before and after the laboratory experiences. The three labs observed were: soda distillation, stoichiometry, and separation of a mixture. Five significant results or correlations were found. For soda distillation, there were two positive correlations. Student preference for analyzing data was positively correlated with achievement on the data analysis dimension of the lab rubric. A student preference for using numbers and graphs to analyze data was positively correlated with achievement on the analysis dimension of the lab rubric. For the separating a mixture lab data the following pairs of correlations were significant. Student preference for doing chemistry labs where numbers and graphs were used to analyze data had a positive correlation with writing a correctly worded hypothesis. Student responses that lab experiences help them learn science positively correlated with achievement on the data dimension of the lab rubric. The only negative correlation found related to the first result where students' preference for computers was inversely correlated to their performance on analyzing data on their lab report. Other findings included the following: students like actual experimental work most and the write-up and analysis of a lab the least. It is recommended that lab science instruction be inquiry-based, hands-on, and that students be tested for lab content acquisition. The final conclusion of the study is that students expressed a preference for working in groups and working with materials and equipment as opposed to individual, non-group work and analyzing data.
A perfect launch viewed across Banana Creek
NASA Technical Reports Server (NTRS)
2000-01-01
Space Shuttle Discovery seems to burst forth from a pillow of smoke as it lifts off from Launch Pad 39A on mission STS-92 to the International Space Station. The brilliant light from the solid rocket booster flames is reflected in nearby water. The perfect on-time liftoff occurred at 7:17 p.m. EDT, sending a crew of seven on the 100th launch in the history of the Shuttle program. Discovery carries a payload that includes the Integrated Truss Structure Z-1, first of 10 trusses that will form the backbone of the Space Station, and the third Pressurized Mating Adapter that will provide a Shuttle docking port for solar array installation on the sixth Station flight and Lab installation on the seventh Station flight. Discovery's landing is expected Oct. 22 at 2:10 p.m. EDT.
The CARIBU EBIS control and synchronization system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dickerson, Clayton, E-mail: cdickerson@anl.gov; Peters, Christopher, E-mail: cdickerson@anl.gov
2015-01-09
The Californium Rare Isotope Breeder Upgrade (CARIBU) Electron Beam Ion Source (EBIS) charge breeder has been built and tested. The bases of the CARIBU EBIS electrical system are four voltage platforms on which both DC and pulsed high voltage outputs are controlled. The high voltage output pulses are created with either a combination of a function generator and a high voltage amplifier, or two high voltage DC power supplies and a high voltage solid state switch. Proper synchronization of the pulsed voltages, fundamental to optimizing the charge breeding performance, is achieved with triggering from a digital delay pulse generator. Themore » control system is based on National Instruments realtime controllers and LabVIEW software implementing Functional Global Variables (FGV) to store and access instrument parameters. Fiber optic converters enable network communication and triggering across the platforms.« less
Potentiometric sensors using cotton yarns, carbon nanotubes and polymeric membranes.
Guinovart, Tomàs; Parrilla, Marc; Crespo, Gastón A; Rius, F Xavier; Andrade, Francisco J
2013-09-21
A simple and generalized approach to build electrochemical sensors for wearable devices is presented. Commercial cotton yarns are first turned into electrical conductors through a simple dyeing process using a carbon nanotube ink. These conductive yarns are then partially coated with a suitable polymeric membrane to build ion-selective electrodes. Potentiometric measurements using these yarn-potentiometric sensors are demonstrated. Examples of yarns that can sense pH, K(+) and NH4(+) are presented. In all cases, these sensing yarns show limits of detection and linear ranges that are similar to those obtained with lab-made solid-state ion-selective electrodes. Through the immobilization of these sensors in a band-aid, it is shown that this approach could be easily implemented in a wearable device. Factors affecting the performance of the sensors and future potential applications are discussed.
MatLab Programming for Engineers Having No Formal Programming Knowledge
NASA Technical Reports Server (NTRS)
Shaykhian, Linda H.; Shaykhian, Gholam Ali
2007-01-01
MatLab is one of the most widely used very high level programming languages for Scientific and engineering computations. It is very user-friendly and needs practically no formal programming knowledge. Presented here are MatLab programming aspects and not just the MatLab commands for scientists and engineers who do not have formal programming training and also have no significant time to spare for learning programming to solve their real world problems. Specifically provided are programs for visualization. Also, stated are the current limitations of the MatLab, which possibly can be taken care of by Mathworks Inc. in a future version to make MatLab more versatile.
Department of Chemistry and Biochemistry - University of Maryland,
Access Analytical Facilities? New Labs Catalyze Chemistry Learning Inclusive & Interdisciplinary New Collaborative Research New Labs Catalyze Chemistry Learning Inclusive & Interdisciplinary New Molecule Shows Author's profile esj-lab New Labs Catalyze Chemistry Learning The Edward St. John Learning and Teaching
NASA Astrophysics Data System (ADS)
Holtstiege, Florian; Schmuch, Richard; Winter, Martin; Brunklaus, Gunther; Placke, Tobias
2018-02-01
Pre-lithiation of anode materials can be an effective method to compensate active lithium loss which mainly occurs in the first few cycles of a lithium ion battery (LIB), due to electrolyte decomposition and solid electrolyte interphase (SEI) formation at the surface of the anode. There are many different pre-lithiation methods, whereas pre-lithiation using metallic lithium constitutes the most convenient and widely utilized lab procedure in literature. In this work, for the first time, solid state nuclear magnetic resonance spectroscopy (NMR) is applied to monitor the reaction kinetics of the pre-lithiation process of graphite with lithium. Based on static 7Li NMR, we can directly observe both the dissolution of lithium metal and parallel formation of LiCx species in the obtained NMR spectra with time. It is also shown that the degree of pre-lithiation as well as distribution of lithium metal on the electrode surface have a strong impact on the reaction kinetics of the pre-lithiation process and on the remaining amount of lithium metal. Overall, our findings are highly important for further optimization of pre-lithiation methods for LIB anode materials, both in terms of optimized pre-lithiation time and appropriate amounts of lithium metal.
Conversion of microwave pyrolysed ASR's char using high temperature agents.
Donaj, Pawel; Blasiak, Wlodzimierz; Yang, Weihong; Forsgren, Christer
2011-01-15
Pyrolysis enables to recover metals and organic feedstock from waste conglomerates such as: automotive shredder residue (ASR). ASR as well as its pyrolysis solid products, is a morphologically and chemically varied mixture, containing mineral materials, including hazardous heavy metals. The aim of the work is to generate fundamental knowledge on the conversion of the organic residues of the solid products after ASR's microwave pyrolysis, treated at various temperatures and with two different types of gasifying agent: pure steam or 3% (v/v) of oxygen. The research is conducted using a lab-scale, plug-flow gasifier, with an integrated scale for analysing mass loss changes over time of experiment, serving as macro TG at 950, 850 and 760 °C. The reaction rate of char decomposition was investigated, based on carbon conversion during gasification and pyrolysis stage. It was found in both fractions that char conversion rate decreases with the rise of external gas temperature, regardless of the gasifying agent. No significant differences between the reaction rates undergoing with steam and oxygen for char decomposition has been observed. This abnormal char behaviour might have been caused by the inhibiting effects of ash, especially alkali metals on char activity or due to deformation of char structure during microwave heating. Copyright © 2010 Elsevier B.V. All rights reserved.
Microparticle sampling by electrowetting-actuated droplet sweeping.
Zhao, Yuejun; Cho, Sung Kwon
2006-01-01
This paper describes a new microparticle sampler where particles can be efficiently swept from a solid surface and sampled into a liquid medium using moving droplets actuated by the electrowetting principle. We successfully demonstrate that super hydrophilic (2 microm and 7.9 microm diameter glass beads of about 14 degrees contact angle), intermediate hydrophilic (7.5 microm diameter polystyrene beads of about 70 degrees contact angle), and super hydrophobic (7.9 microm diameter Teflon-coated glass beads and 3 microm size PTFE particles of over 110 degrees contact angles) particles on a solid surface are picked up by electrowetting-actuated moving droplets. For the glass beads as well as the polystyrene beads, the sampling efficiencies are over 93%, in particular over 98% for the 7.9 microm glass beads. For the PTFE particles, however, the sampling efficiency is measured at around 70%, relatively lower than that of the glass and polystyrene beads. This is due mainly to the non-uniformity in particle size and the particle hydrophobicity. In this case, the collected particles staying (adsorbing) on the air-to-water interface hinder the droplet from advancing. This particle sampler requires an extremely small amount of liquid volume (about 500 nanoliters) and will thus be highly compatible and easily integrated with lab-on-a-chip systems for follow-up biological/chemical analyses.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swansiger, W.A.; Shepodd, T.J.; Phillips, M.L.F.
The ability to identify the manufacturers and distributors of chemicals seized in raids of illicit drug labs would be of great value in controlling the diversion of these chemicals. We developed a tagging scheme based on the addition of sub-ppM concentrations of various combinations of rare-earth elements to the target chemicals and evaluated a number of techniques for detecting the tags. We developed soluble tags for tagging liquids and selected Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) as the preferred detection technique. We developed insoluble tags for tagging solids and developed methods to analyze them and mix them into solid precursors. Wemore » have successfully demonstrated the tagging of several solvents and two of the precursor chemicals used in one of the most popular clandestine methamphetamine syntheses (ephedrine reacting with hydriodic acid/red phosphorus). The tagging scheme is capable of yielding tens of thousands of signatures (using holmium as an internal standard and up to 9 rare-earths at up to 3 concentrations yields 3{sup 9} {minus} 1 = 19,682 signatures) and is applicable to most of the chemicals on the precursor and essential chemicals list. In the concentrations employed, the tags are safe enough to be added to pharmaceuticals and cheap enough to tag tanker loads of chemicals.« less
Raman mapping of mannitol/lysozyme particles produced via spray drying and single droplet drying.
Pajander, Jari Pekka; Matero, Sanni; Sloth, Jakob; Wan, Feng; Rantanen, Jukka; Yang, Mingshi
2015-06-01
This study aimed to investigate the effect of a model protein on the solid state of a commonly used bulk agent in spray-dried formulations. A series of lysozyme/mannitol formulations were spray-dried using a lab-scale spray dryer. Further, the surface temperature of drying droplet/particles was monitored using the DRYING KINETICS ANALYZER™ (DKA) with controllable drying conditions mimicking the spray-drying process to estimate the drying kinetics of the lysozyme/mannitol formulations. The mannitol polymorphism and the spatial distribution of lysozyme in the particles were examined using X-ray powder diffractometry (XRPD) and Raman microscopy. Partial Least Squares Discriminant Analysis was used for analyzing the Raman microscopy data. XRPD results indicated that a mixture of β-mannitol and α-mannitol was produced in the spray-drying process which was supported by the Raman analysis, whereas Raman analysis indicated that a mixture of α-mannitol and δ-mannitol was detected in the single particles from DKA. In addition Raman mapping indicated that the presence of lysozyme seemed to favor the appearance of α-mannitol in the particles from DKA evidenced by close proximity of lysozyme and mannitol in the particles. It suggested that the presence of lysozyme tend to induce metastable solid state forms upon the drying process.
NASA Astrophysics Data System (ADS)
Karlsen, Jonas; Bruus, Henrik
2015-11-01
We present a theoretical analysis (arxiv.org/abs/1507.01043) of the acoustic radiation force on a single small particle, either a thermoviscous fluid droplet or a thermoelastic solid particle, suspended in a viscous and heat-conducting fluid. Our analysis places no restrictions on the viscous and thermal boundary layer thicknesses relative to the particle radius, but it assumes the particle to be small in comparison to the acoustic wavelength. This is the limit relevant to scattering of ultrasound waves from sub-micrometer particles. For particle sizes smaller than the boundary layer widths, our theory leads to profound consequences for the acoustic radiation force. For example, for liquid droplets and solid particles suspended in gasses we predict forces orders of magnitude larger than expected from ideal-fluid theory. Moreover, for certain relevant choices of materials, we find a sign change in the acoustic radiation force on different-sized but otherwise identical particles. These findings lead to the concept of a particle-size-dependent acoustophoretic contrast factor, highly relevant to applications in acoustic levitation or separation of micro-particles in gases, as well as to handling of μm- and nm-sized particles such as bacteria and vira in lab-on-a-chip systems.
Technologies for reducing sludge production in wastewater treatment plants: State of the art.
Wang, Qilin; Wei, Wei; Gong, Yanyan; Yu, Qiming; Li, Qin; Sun, Jing; Yuan, Zhiguo
2017-06-01
This review presents the state-of-the-art sludge reduction technologies applied in both wastewater and sludge treatment lines. They include chemical, mechanical, thermal, electrical treatment, addition of chemical un-coupler, and predation of protozoa/metazoa in wastewater treatment line, and physical, chemical and biological pretreatment in sludge treatment line. Emphasis was put on their effect on sludge reduction performance, with 10% sludge reduction to zero sludge production in wastewater treatment line and enhanced TS (total solids) or volatile solids removal of 5-40% in sludge treatment line. Free nitrous acid (FNA) technology seems good in wastewater treatment line but it is only under the lab-scale trial. In sludge treatment line, thermal, ultrasonic (<4400kJ/kg TS), FNA pretreatment and temperature-phased anaerobic digestion (TPAD) are promising if pathogen inactivation is not a concern. However, thermal pretreatment and TPAD are superior to other pretreatment technologies when pathogen inactivation is required. The new wastewater treatment processes including SANI®, high-rate activated sludge coupled autotrophic nitrogen removal and anaerobic membrane bioreactor coupled autotrophic nitrogen removal also have a great potential to reduce sludge production. In the future, an effort should be put on the effect of sludge reduction technologies on the removal of organic micropollutants and heavy metals. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Dietrich, Ralph-Uwe; Oelze, Jana; Lindermeir, Andreas; Spitta, Christian; Steffen, Michael; Küster, Torben; Chen, Shaofei; Schlitzberger, Christian; Leithner, Reinhard
The transfer of high electrical efficiencies of solid oxide fuel cells (SOFC) into praxis requires appropriate system concepts. One option is the anode-offgas recycling (AOGR) approach, which is based on the integration of waste heat using the principle of a chemical heat pump. The AOGR concept allows a combined steam- and dry-reforming of hydrocarbon fuel using the fuel cell products steam and carbon dioxide. SOFC fuel gas of higher quantity and quality results. In combination with internal reuse of waste heat the system efficiency increases compared to the usual path of partial oxidation (POX). The demonstration of the AOGR concept with a 300 Wel-SOFC stack running on propane required: a combined reformer/burner-reactor operating in POX (start-up) and AOGR modus; a hotgas-injector for anode-offgas recycling to the reformer; a dynamic process model; a multi-variable process controller; full system operation for experimental proof of the efficiency gain. Experimental results proof an efficiency gain of 18 percentage points (η·POX = 23%, η·AOGR = 41%) under idealized lab conditions. Nevertheless, further improvements of injector performance, stack fuel utilization and additional reduction of reformer reformer O/C ratio and system pressure drop are required to bring this approach into self-sustaining operation.
NASA Technical Reports Server (NTRS)
DellaCorte, Christopher; Valco, Mark J.
1999-01-01
The NASA Lewis Research Center is capitalizing on breakthroughs in foil air bearing performance, tribological coatings, and computer analyses to formulate the Oil-free Turbomachinery Program. The program s long-term goal is to develop an innovative, yet practical, oil-free aeropropulsion gas turbine engine that floats on advanced air bearings. This type of engine would operate at higher speeds and temperatures with lower weight and friction than conventional oil-lubricated engines. During startup and shutdown, solid lubricant coatings are required to prevent wear in such engines before the self-generating air-lubrication film develops. NASA s Tribology Branch has created PS304, a chrome-oxide-based plasma spray coating specifically tailored for shafts run against foil bearings. PS304 contains silver and barium fluoride/calcium fluoride eutectic (BaF2/CaF2) lubricant additives that, together, provide lubrication from cold start temperatures to over 650 C, the maximum use temperature for foil bearings. Recent lab tests show that bearings lubricated with PS304 survive over 100 000 start-stop cycles without experiencing any degradation in performance due to wear. The accompanying photograph shows a test bearing after it was run at 650 C. The rubbing process created a "polished" surface that enhances bearing load capacity.
Zhong, Ming; Huang, Ke-Long; Zeng, Jian-Guo; Li, Shuang; She, Jin-Ming; Li, Guiyin; Zhang, Li
2010-07-01
The purpose of the research was to investigate the multiple response optimizations for the extraction of protopine and allocryptopine from the stems of Macleaya cordata (Willd) R. Br. by using microwave-assisted extraction (MAE). A three-level, three-factor Box-Behnken design of response surface methodology was used to develop response model, and desirability function was employed to optimize the effects of main extraction parameters. Three variables, ethanol concentration (20-80%, v/v), extraction temperature (30-70 degrees C) and solvent/solid ratio (10:1 to 30:1, mL/g), were investigated in this study. The results showed that the optimum parameters of MAE were ethanol concentration of 45.2 % (v/v), extraction temperature of 54.7 degrees C and solvent/solid ratio of 20.4:1 (mL/g). Under these conditions, the extraction yields of protopine and allocryptopine were 89.4 and 102.0%, respectively, and the extracta sicca yield was 12.5%. The combination use of response surface methodology, Box-Behnken design and the appropriate desirability function could provide an insight into a lab-scale MAE process, and help to develop procedures for commercial production of active ingredients from medical plants.
Effectiveness of a Lab Manual Delivered on CD-ROM
ERIC Educational Resources Information Center
Brickman, Peggy; Ketter, Catherine A. Teare; Pereira, Monica
2005-01-01
Although electronic instructional media are becoming increasingly prevalent in science classrooms, their worth remains unproven. Here, student perceptions and performance using CD-ROM delivery of lab materials are assessed. Numerous learning barriers that produced lower lab grades for students using a CD-ROM lab manual in comparison to a print…
Student Plagiarism and Faculty Responsibility in Undergraduate Engineering Labs
ERIC Educational Resources Information Center
Parameswaran, Ashvin; Devi, Poornima
2006-01-01
In undergraduate engineering labs, lab reports are routinely copied. By ignoring this form of plagiarism, teaching assistants and lab technicians neglect their role responsibility. By designing courses that facilitate it, however inadvertently, professors neglect their causal responsibility. Using the case of one university, we show via interviews…
Experiential Learning of Digital Communication Using LabVIEW
ERIC Educational Resources Information Center
Zhan, Wei; Porter, Jay R.; Morgan, Joseph A.
2014-01-01
This paper discusses the design and implementation of laboratories and course projects using LabVIEW in an instrumentation course. The pedagogical challenge is to enhance students' learning of digital communication using LabVIEW. LabVIEW was extensively used in the laboratory sessions, which better prepared students for the course projects. Two…
Blood Count Tests - Multiple Languages
... window. Arabic (العربية) Expand Section Your Lab Tests - English PDF Your Lab Tests - العربية (Arabic) PDF American ... Cantonese dialect) (繁體中文) Expand Section Your Lab Tests - English PDF Your Lab Tests - 繁體中文 (Chinese, Traditional (Cantonese ...
Computers, Networks, and Desegregation at San Jose High Academy.
ERIC Educational Resources Information Center
Solomon, Gwen
1987-01-01
Describes magnet high school which was created in California to meet desegregation requirements and emphasizes computer technology. Highlights include local computer networks that connect science and music labs, the library/media center, business computer lab, writing lab, language arts skills lab, and social studies classrooms; software; teacher…
NASA Tech Briefs, February 2012
NASA Technical Reports Server (NTRS)
2012-01-01
This issue contains the following briefs: (1) Optical Comb from a Whispering Gallery Mode Resonator for Spectroscopy and Astronomy Instruments Calibration (2) Real-Time Flight Envelope Monitoring System (3) Nemesis Autonomous Test System (4) Mirror Metrology Using Nano-Probe Supports (5) Automated Lab-on-a-Chip Electrophoresis System (6) Techniques for Down-Sampling a Measured Surface Height Map for Model Validation (7) Multi-Component, Multi-Point Interferometric Rayleigh/Mie Doppler Velocimeter (8) Frequency to Voltage Converter Analog Front-End Prototype (9) Dust-Tolerant Intelligent Electrical Connection System (10) Gigabit Ethernet Asynchronous Clock Compensation FIFO (11) High-Speed, Multi-Channel Serial ADC LVDS Interface for Xilinx Virtex-5 FPGA (12) Glovebox for GeoLab Subsystem in HDU1-PEM (13) Modified Process Reduces Porosity when Soldering in Reduced Gravity Environments (14) Use of Functionalized Carbon Nanotubes for Covalent Attachment of Nanotubes to Silicon (15) Flexible Plug Repair for Shuttle Wing Leading Edge (16) Three Dimensionally Interlinked, Dense, Solid Form of Single-Walled CNT Ropes (17) Axel Robotic Platform for Crater and Extreme Terrain Exploration (18) Site Tamper and Material Plow Tool - STAMP (19) Magnetic Interface for Segmented Mirror Assembly (20) Transpiration-Cooled Spacecraft-Insulation-Repair Fasteners (21) Fluorescence-Based Sensor for Monitoring Activation of Lunar Dust (22) Aperture Ion Source (23) Virtual Ultrasound Guidance for Inexperienced Operators (24) Model-Based Fault Diagnosis: Performing Root Cause and Impact Analyses in Real Time (25) Interactive Schematic Integration Within the Propellant System Modeling Environment (26) Magnetic and Electric Field Polarizations of Oblique Magnetospheric Chorus Waves (27) Variable Sampling Mapping.
Nitrogen oxides emissions from the MILD combustion with the conditions of recirculation gas.
Park, Min; Shim, Sung Hoon; Jeong, Sang Hyun; Oh, Kwang-Joong; Lee, Sang-Sup
2017-04-01
The nitrogen oxides (NO x ) reduction technology by combustion modification which has economic benefits as a method of controlling NO x emitted in the combustion process, has recently been receiving a lot of attention. Especially, the moderate or intense low oxygen dilution (MILD) combustion which applied high temperature flue gas recirculation has been confirmed for its effectiveness with regard to solid fuel as well. MILD combustion is affected by the flue gas recirculation ratio and the composition of recirculation gas, so its NO x reduction efficiency is determined by them. In order to investigate the influence of factors which determine the reduction efficiency of NO x in MILD coal combustion, this study changed the flow rate and concentration of nitrogen (N 2 ), carbon dioxide (CO 2 ) and steam (H 2 O) which simulate the recirculation gas during the MILD coal combustion using our lab-scale drop tube furnace and performed the combustion experiment. As a result, its influence by the composition of recirculation gas was insignificant and it was shown that flue gas recirculation ratio influences the change of NO x concentration greatly. We investigated the influence of factors determining the nitrogen oxides (NO x ) reduction efficiency in MILD coal combustion, which applied high-temperature flue gas recirculation. Using a lab-scale drop tube furnace and simulated recirculation gas, we conducted combustion testing changing the recirculation gas conditions. We found that the flue gas recirculation ratio influences the reduction of NO x emissions the most.
Zhang, Le; Zhang, Jingxin; Loh, Kai-Chee
2018-05-01
Effects of activated carbon (AC) supplementation on anaerobic digestion (AD) of food waste were elucidated in lab- and pilot-scales. Lab-scale AD was performed in 1 L and 8 L digesters, while pilot-scale AD was conducted in a 1000 L digester. Based on the optimal dose of 15 g AC per working volume derived from the 1 L digester, for the same AC dosage in the 8 L digester, an improved operation stability coupled with a higher methane yield was achieved even when digesters without AC supplementation failed after 59 days due to accumulation of substantial organic intermediates. At the same time, color removal from the liquid phase of the digestate was dramatically enhanced and the particle size of the digestate solids was increased by 53% through AC supplementation after running for 59 days. Pyrosequencing of 16S rRNA gene showed the abundance of predominant phyla Firmicutes, Elusimicrobia and Proteobacteria selectively enhanced by 1.7-fold, 2.9-fold and 2.1-fold, respectively. Pilot-scale digester without AC gave an average methane yield of 0.466 L⋅(gVS) -1 ⋅d -1 at a composition of 53-61% v/v methane. With AC augmentation, an increase of 41% in methane yield was achieved in the 1000 L digester under optimal organic loading rate (1.6 g VS FW ·L -1 ·d -1 ). Copyright © 2018 Elsevier Ltd. All rights reserved.
Miniaturized devices towards an integrated lab-on-a-chip platform for DNA diagnostics
NASA Astrophysics Data System (ADS)
Kaprou, G.; Papadakis, G.; Kokkoris, G.; Papadopoulos, V.; Kefala, I.; Papageorgiou, D.; Gizeli, E.; Tserepi, A.
2015-06-01
Microfluidics is an emerging technology enabling the development of Lab-on-a-chip (LOC) systems for clinical diagnostics, drug discovery and screening, food safety and environmental analysis. LOC systems integrate and scale down one or several laboratory functions on a single chip of a few mm2 to cm2 in size, and account for many advantages on biochemical analyses, such as low sample and reagent consumption, low cost, reduced analysis time, portability and point-of-need compatibility. Currently, available nucleic acid diagnostic tests take advantage of Polymerase Chain Reaction (PCR) that allows exponential amplification of portions of nucleic acid sequences that can be used as indicators for the identification of various diseases. Here, we present a comparison between static chamber and continuous flow miniaturized PCR devices, in terms of energy consumption for devices fabricated on the same material stack, with identical sample volume and channel dimensions. The comparison is implemented by a computational study coupling heat transfer in both solid and fluid, mass conservation of species, and joule heating. Based on the conclusions of this study, we develop low-cost and fast DNA amplification devices for both PCR and isothermal amplification, and we implement them in the detection of mutations related to breast cancer. The devices are fabricated by mass production amenable technologies on printed circuit board (PCB) substrates, where copper facilitates the incorporation of on-chip microheaters, defining the thermal zones necessary for PCR or isothermal amplification methods.
1981-11-01
STONE). &7 LAB 07 AORD LAB APRL 1978 LAB * 107/78.6118 PRESQUE ISLE PROJECT UNK ORD LAB CLEVELAND WEST BREAKWATER JU. LAB 103/78.6240 .R..ABILITATION...NOTES IS. KEY WORDS (Continue on revere side if neeemvr and identify by block number) beach erosion diked disposal areas shore erosion Lake Erie ...House Document No. 229, 83rd Congress, "Appendix VIII, Ohio Shoreline of Lake Erie Between Vermilion and Sheffield Lake Village, Beach Erosion Control
Improving the Quality of Lab Reports by Using Them as Lab Instructions
NASA Astrophysics Data System (ADS)
Haagen-Schuetzenhoefer, Claudia
2012-10-01
Lab exercises are quite popular in teaching science. Teachers have numerous goals in mind when teaching science laboratories. Nevertheless, empirical research draws a heterogeneous picture of the benefits of lab work. Research has shown that it does not necessarily contribute to the enhancement of practical abilities or content knowledge. Lab activities are frequently based on recipe-like, step-by-step instructions ("cookbook style"), which do not motivate students to engage cognitively. Consequently, students put the emphasis on "task completion" or "manipulating equipment."2
GeneLab: Open Science For Exploration
NASA Technical Reports Server (NTRS)
Galazka, Jonathan
2018-01-01
The NASA GeneLab project capitalizes on multi-omic technologies to maximize the return on spaceflight experiments. The GeneLab project houses spaceflight and spaceflight-relevant multi-omics data in a publicly accessible data commons, and collaborates with NASA-funded principal investigators to maximize the omics data from spaceflight and spaceflight-relevant experiments. I will discuss the current status of GeneLab and give specific examples of how the GeneLab data system has been used to gain insight into how biology responds to spaceflight conditions.
The Effect of Triage on Patient Flow in an Outpatient Clinic.
1979-12-01
returns the records to the reception desk, and then checks his in- basket to call his next patient. If lab tests or X-rays are indicated and the patient is...Waiting times 7 Start and end of Provider service time provider service Total service time 8 Lab tests Percentage of lab tests ordered by screener 9 Lab... tests Percentage of lab tests ordered by provider Second provider start Provider service time and end of service Total service time 10 Referral to
Indicators for the use of robotic labs in basic biomedical research: a literature analysis
2017-01-01
Robotic labs, in which experiments are carried out entirely by robots, have the potential to provide a reproducible and transparent foundation for performing basic biomedical laboratory experiments. In this article, we investigate whether these labs could be applicable in current experimental practice. We do this by text mining 1,628 papers for occurrences of methods that are supported by commercial robotic labs. Using two different concept recognition tools, we find that 86%–89% of the papers have at least one of these methods. This and our other results provide indications that robotic labs can serve as the foundation for performing many lab-based experiments. PMID:29134146
Characterization of Lactic Acid Bacteria (LAB) isolated from Indonesian shrimp paste (terasi)
NASA Astrophysics Data System (ADS)
Amalia, U.; Sumardianto; Agustini, T. W.
2018-02-01
Shrimp paste was one of fermented products, popular as a taste enhancer in many dishes. The processing of shrimp paste was natural fermentation, depends on shrimp it self and the presence of salt. The salt inhibits the growth of undesirable microorganism and allows the salt-tolerant lactic acid bacteria (LAB) to ferment the protein source to lactic acids. The objectives of this study were to characterize LAB isolated from Indonesian shrimp paste or "Terasi" with different times of fermentation (30, 60 and 90 days). Vitech analysis showed that there were four strains of the microorganism referred to as lactic acid bacteria (named: LABS1, LABS2, LABS3 and LABS4) with 95% sequence similarity. On the basis of biochemical, four isolates represented Lactobacillus, which the name Lactobacillus plantarum is proposed. L.plantarum was play role in resulting secondary metabolites, which gave umami flavor in shrimp paste.
Natarajan, Annamalai; Angarita, Gustavo; Gaiser, Edward; Malison, Robert; Ganesan, Deepak; Marlin, Benjamin M
2016-09-01
Mobile health research on illicit drug use detection typically involves a two-stage study design where data to learn detectors is first collected in lab-based trials, followed by a deployment to subjects in a free-living environment to assess detector performance. While recent work has demonstrated the feasibility of wearable sensors for illicit drug use detection in the lab setting, several key problems can limit lab-to-field generalization performance. For example, lab-based data collection often has low ecological validity, the ground-truth event labels collected in the lab may not be available at the same level of temporal granularity in the field, and there can be significant variability between subjects. In this paper, we present domain adaptation methods for assessing and mitigating potential sources of performance loss in lab-to-field generalization and apply them to the problem of cocaine use detection from wearable electrocardiogram sensor data.
Enhanced sludge dewatering by electrofiltration. A feasibility study.
Saveyn, H; Huybregts, L; Van der Meeren, P
2001-01-01
Sludge treatment is a major issue in today's waste water treatment. One of the problems encountered is the limiting dewaterability of mainly biological sludges, causing high final treatment costs for incineration or landfill. Although during recent years, improvements are realised in the field of dewatering, the actual dry solids content after dewatering remains at a maximum value of about 35%. In order to increase the dry solids content, the technique of electrofiltration was investigated. Electrofiltration is the combination of two known techniques, traditional pressure filtration and electroosmotic/electrophoretic dewatering. Pressure filtration is based on pressure as the driving force for dewatering a sludge. Limitations hereby lie in the clogging of the filter cloth due to the build-up of the filtercake. Electroosmotic/electrophoretic dewatering is based on an electric field to separate sludge colloid particles from the surrounding liquid by placing the sludge liquor between two oppositely charged electrodes. In this case, mobile sludge particles will move to one electrode due to their natural surface charge, and the liquid phase will be collected at the oppositely charged electrode. Combination of both techniques makes it possible to create a more homogeneous filter cake and prevent the filter from clogging, resulting in higher cake dry solids contents and shorter filtration cycles. To investigate the feasibility of this technique for the dewatering of activated sludge, a filter unit was developed for investigations on lab scale. Multiple dewatering tests were performed in which the electric parameters for electrofiltration were varied. It was derived from these experiments that very high filter cake dry solids contents (to more than 60%), and short filtration cycles were attainable by using a relatively small electric DC field. The power consumption was very low compared to the power needed to dewater sludge by thermal drying techniques. For this reason, this technique seems very promising for the dewatering of biological sludges.
Improving the Quality of Lab Reports by Using Them as Lab Instructions
ERIC Educational Resources Information Center
Haagen-Schuetzenhoefer, Claudia
2012-01-01
Lab exercises are quite popular in teaching science. Teachers have numerous goals in mind when teaching science laboratories. Nevertheless, empirical research draws a heterogeneous picture of the benefits of lab work. Research has shown that it does not necessarily contribute to the enhancement of practical abilities or content knowledge. Lab…
The Development of MSFC Usability Lab
NASA Technical Reports Server (NTRS)
Cheng, Yiwei; Richardson, Sally
2010-01-01
This conference poster reviews the development of the usability lab at Marshall Space Flight Center. The purpose of the lab was to integrate a fully functioning usability laboratory to provide a resource for future human factor assessments. and to implement preliminary usability testing on a MSFC website to validate the functionality of the lab.
LabLessons: Effects of Electronic Prelabs on Student Engagement and Performance
ERIC Educational Resources Information Center
Gryczka, Patrick; Klementowicz, Edward; Sharrock, Chappel; Maxfield, MacRae; Montclare, Jin Kim
2016-01-01
Lab instructors, for both high school and undergraduate college level courses, face issues of constricted time within the lab period and limited student engagement with prelab materials. To address these issues, an online prelab delivery system named LabLessons is developed and tested out in a high school chemistry classroom. The system…
75 FR 6997 - Federal Property Suitable as Facilities To Assist the Homeless
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-12
... Agency, 143 Billy Mitchell Blvd., Suite 1, San Antonio, TX 78226; (210) 925-3047; GSA: Gordon Creed... Research Lab Bldg. 247 Rome Lab Rome Co: Oneida NY 13441 Property Number: 18200340024 Status: Unutilized Comments: 13199 sq. ft., presence of asbestos, most recent use-- Electronic Research Lab Bldg. 248 Rome Lab...
Lab at Home: Hardware Kits for a Digital Design Lab
ERIC Educational Resources Information Center
Oliver, J. P.; Haim, F.
2009-01-01
An innovative laboratory methodology for an introductory digital design course is presented. Instead of having traditional lab experiences, where students have to come to school classrooms, a "lab at home" concept is proposed. Students perform real experiments in their own homes, using hardware kits specially developed for this purpose. They…
Outreach Science Education: Evidence-Based Studies in a Gene Technology Lab
ERIC Educational Resources Information Center
Scharfenberg, Franz-Josef; Bogner, Franz X.
2014-01-01
Nowadays, outreach labs are important informal learning environments in science education. After summarizing research to goals outreach labs focus on, we describe our evidence-based gene technology lab as a model of a research-driven outreach program. Evaluation-based optimizations of hands-on teaching based on cognitive load theory (additional…
The Portable Usability Testing Lab: A Flexible Research Tool.
ERIC Educational Resources Information Center
Hale, Michael E.; And Others
A group of faculty at the University of Georgia obtained funding for a research and development facility called the Learning and Performance Support Laboratory (LPSL). One of the LPSL's primary needs was obtaining a portable usability lab for software testing, so the facility obtained the "Luggage Lab 2000." The lab is transportable to…
Can Graduate Teaching Assistants Teach Inquiry-Based Geology Labs Effectively?
ERIC Educational Resources Information Center
Ryker, Katherine; McConnell, David
2014-01-01
This study examines the implementation of teaching strategies by graduate teaching assistants (GTAs) in inquiry-based introductory geology labs at a large research university. We assess the degree of inquiry present in each Physical Geology lab and compare and contrast the instructional practices of new and experienced GTAs teaching these labs. We…
ERIC Educational Resources Information Center
Preusse-Burr, Beatrix
2011-01-01
Many classrooms have interactive whiteboards and several computers and many schools are equipped with a computer lab and mobile labs. However, there typically are not enough computers for every student in each classroom; mobile labs are often shared between several members of a team and time in the computer labs needs to be scheduled in advance.…
Constructing the Components of a Lab Report Using Peer Review
ERIC Educational Resources Information Center
Berry, David E.; Fawkes, Kelli L.
2010-01-01
A protocol that emphasizes lab report writing using a piecemeal approach coupled with peer review is described. As the lab course progresses, the focus of the report writing changes sequentially through the abstract and introduction, the discussion, and the procedure. Two styles of lab programs are presented. One style rotates the students through…
Undergraduate Student Construction and Interpretation of Graphs in Physics Lab Activities
ERIC Educational Resources Information Center
Nixon, Ryan S.; Godfrey, T. J.; Mayhew, Nicholas T.; Wiegert, Craig C.
2016-01-01
Lab activities are an important element of an undergraduate physics course. In these lab activities, students construct and interpret graphs in order to connect the procedures of the lab with an understanding of the related physics concepts. This study investigated undergraduate students' construction and interpretation of graphs with best-fit…
77 FR 64143 - Manufacturer of Controlled Substances; Notice of Registration; Cambridge Isotope Lab
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-18
...; Notice of Registration; Cambridge Isotope Lab By Notice dated June 18, 2012, and published in the Federal Register on June 26, 2012, 77 FR 38086, Cambridge Isotope Lab, 50 Frontage Road, Andover, Massachusetts....C. 823(a) and determined that the registration of Cambridge Isotope Lab to manufacture the listed...
NASA Astrophysics Data System (ADS)
Malik, A.; Setiawan, A.; Suhandi, A.; Permanasari, A.; Dirgantara, Y.; Yuniarti, H.; Sapriadil, S.; Hermita, N.
2018-01-01
This study aimed to investigate the improvement to pre-service teacher’s communication skills through Higher Order Thinking Laboratory (HOT Lab) on electric circuit topic. This research used the quasi-experiment method with pretest-posttest control group design. Research subjects were 60 students of Physics Education in UIN Sunan Gunung Djati Bandung. The sample was chosen by random sampling technique. Students’ communication skill data collected using a communication skills test instruments-essays form and observations sheets. The results showed that pre-service teacher communication skills using HOT Lab were higher than verification lab. Student’s communication skills in groups using HOT Lab were not influenced by gender. Communication skills could increase due to HOT Lab based on problems solving that can develop communication through hands-on activities. Therefore, the conclusion of this research shows the application of HOT Lab is more effective than the verification lab to improve communication skills of pre-service teachers in electric circuit topic and gender is not related to a person’s communication skills.
Experiences with lab-centric instruction
NASA Astrophysics Data System (ADS)
Titterton, Nathaniel; Lewis, Colleen M.; Clancy, Michael J.
2010-06-01
Lab-centric instruction emphasizes supervised, hands-on activities by substituting lab for lecture time. It combines a multitude of pedagogical techniques into the format of an extended, structured closed lab. We discuss the range of benefits for students, including increased staff interaction, frequent and varied self-assessments, integrated collaborative activities, and a systematic sequence of activities that gradually increases in difficulty. Instructors also benefit from a deeper window into student progress and understanding. We follow with discussion of our experiences in courses at U.C. Berkeley, and using data from some of these investigate the effects of lab-centric instruction on student learning, procrastination, and course pacing. We observe that the lab-centric format helped students on exams but hurt them on extended programming assignments, counter to our hypothesis. Additionally, we see no difference in self-ratings of procrastination and limited differences in ratings of course pace. We do find evidence that the students who choose to attend lab-centric courses are different in several important ways from students who choose to attend the same course in a non-lab-centric format.
Learning Experience on Transformer Using HOT Lab for Pre-service Physics Teacher’s
NASA Astrophysics Data System (ADS)
Malik, A.; Setiawan, A.; Suhandi, A.; Permanasari, A.
2017-09-01
This study aimed at investigating pre-service teacher’s critical thinking skills improvement through Higher Order Thinking (HOT) Lab on transformer learning. This research used mix method with the embedded experimental model. Research subjects are 60 students of Physics Education in UIN Sunan Gunung Djati Bandung. The results showed that based on the results of the analysis of practical reports and observation sheet shows students in the experimental group was better in carrying out the practicum and can solve the real problem while the control group was going on the opposite. The critical thinking skills of students applying the HOT Lab were higher than the verification lab. Critical thinking skills could increase due to HOT Lab based problems solving that can develop higher order thinking skills through laboratory activities. Therefore, it was concluded that the application of HOT Lab was more effective than verification lab on improving students’ thinking skills on transformer topic learning. Finally, HOT Lab can be implemented in other subject learning and could be used to improve another higher order thinking skills.
Zbrun, María V.; Soto, Lorena P.; Bertozzi, Ezequiel; Sequeira, Gabriel J.; Marti, Luis E.; Signorini, Marcelo L.; Armesto, Roberto Rodríguez; Rosmini, Marcelo R.
2012-01-01
The purpose of this study was to evaluate the capacity of a lactic acid bacteria (LAB) inoculum to protect calves with or without lactose supplements against Salmonella Dublin infection by evaluating histopathological lesions and pathogen translocation. Fifteen calves were divided into three groups [control group (C-G), a group inoculated with LAB (LAB-G), and a group inoculated with LAB and given lactose supplements (L-LAB-G)] with five, six, and four animals, respectively. The inoculum, composed of Lactobacillus (L.) casei DSPV 318T, L. salivarius DSPV 315T, and Pediococcus acidilactici DSPV 006T, was administered with milk replacer. The LAB-G and L-LAB-G received a daily dose of 109 CFU/kg body weight of each strain throughout the experiment. Lactose was provided to the L-LAB-G in doses of 100 g/day. Salmonella Dublin (2 × 1010 CFU) was orally administered to all animals on day 11 of the experiment. The microscopic lesion index values in target organs were 83%, 70%, and 64.3% (p < 0.05) for the C-G, LAB-G, and L-LAB-G, respectively. Administration of the probiotic inoculum was not fully effective against infection caused by Salmonella. Although probiotic treatment was unable to delay the arrival of pathogen to target organs, it was evident that the inoculum altered the response of animals against pathogen infection. PMID:23000583
Lactic acid bacteria contribution to gut microbiota complexity: lights and shadows
Pessione, Enrica
2012-01-01
Lactic Acid Bacteria (LAB) are ancient organisms that cannot biosynthesize functional cytochromes, and cannot get ATP from respiration. Besides sugar fermentation, they evolved electrogenic decarboxylations and ATP-forming deiminations. The right balance between sugar fermentation and decarboxylation/deimination ensures buffered environments thus enabling LAB to survive in human gastric trait and colonize gut. A complex molecular cross-talk between LAB and host exists. LAB moonlight proteins are made in response to gut stimuli and promote bacterial adhesion to mucosa and stimulate immune cells. Similarly, when LAB are present, human enterocytes activate specific gene expression of specific genes only. Furthermore, LAB antagonistic relationships with other microorganisms constitute the basis for their anti-infective role. Histamine and tyramine are LAB bioactive catabolites that act on the CNS, causing hypertension and allergies. Nevertheless, some LAB biosynthesize both gamma-amino-butyrate (GABA), that has relaxing effect on gut smooth muscles, and beta-phenylethylamine, that controls satiety and mood. Since LAB have reduced amino acid biosynthetic abilities, they developed a sophisticated proteolytic system, that is also involved in antihypertensive and opiod peptide generation from milk proteins. Short-chain fatty acids are glycolytic and phosphoketolase end-products, regulating epithelial cell proliferation and differentiation. Nevertheless, they constitute a supplementary energy source for the host, causing weight gain. Human metabolism can also be affected by anabolic LAB products such as conjugated linoleic acids (CLA). Some CLA isomers reduce cancer cell viability and ameliorate insulin resistance, while others lower the HDL/LDL ratio and modify eicosanoid production, with detrimental health effects. A further appreciated LAB feature is the ability to fix selenium into seleno-cysteine. Thus, opening interesting perspectives for their utilization as antioxidant nutraceutical vectors. PMID:22919677
Probiotics versus antibiotic decontamination of the digestive tract: infection and mortality.
Oudhuis, Guy J; Bergmans, Dennis C; Dormans, Tom; Zwaveling, Jan-Harm; Kessels, Alfons; Prins, Martin H; Stobberingh, Ellen E; Verbon, Annelies
2011-01-01
Selective decontamination of the digestive tract (SDD) has been shown to decrease the infection rate and mortality in intensive care units (ICUs); Lactobacillus plantarum 299/299v plus fibre (LAB) has been used for infection prevention and does not harbour the potential disadvantages of antibiotics. The objective was to assess whether LAB is not inferior to SDD in infection prevention. Two hundred fifty-four consecutive ICU patients with expected mechanical ventilation ≥ 48 h and/or expected ICU stay ≥ 72 h were assigned to receive SDD: four times daily an oral paste (polymyxin E, gentamicin, amphotericin B), enteral solution (same antibiotics), intravenous cefotaxime (first 4 days) or LAB: two times daily L. plantarum 299/299v with rose-hip. The primary endpoint was infection rate. A difference <12% between both groups indicated non-inferiority of LAB. The trial was prematurely stopped after a study reporting increased mortality in critically ill pancreatitis patients receiving probiotics. No significant difference in infection rate [31% in the LAB group, 24% in the SDD group (OR 1.68, 95% CI 0.91-3.08; p = 0.10)] was found. ICU mortality was 26% and not significantly different between the LAB and SDD groups. Gram-positive cocci and Pseudomonas aeruginosa were significantly more frequently isolated from surveillance cultures in the SDD group compared to the LAB group (for sputum: 18 vs. 10% and 33 vs. 14%). Significantly more Enterobacteriaceae were found in the LAB group (23 vs. 50%). No increase in antibiotic resistance was found during and after SDD or LAB use. The trial could not demonstrate the non-inferiority of LAB compared with SDD in infection prevention. Results suggest no increased ICU mortality risk in the LAB group.
Computer-based Astronomy Labs for Non-science Majors
NASA Astrophysics Data System (ADS)
Smith, A. B. E.; Murray, S. D.; Ward, R. A.
1998-12-01
We describe and demonstrate two laboratory exercises, Kepler's Third Law and Stellar Structure, which are being developed for use in an astronomy laboratory class aimed at non-science majors. The labs run with Microsoft's Excel 98 (Macintosh) or Excel 97 (Windows). They can be run in a classroom setting or in an independent learning environment. The intent of the labs is twofold; first and foremost, students learn the subject matter through a series of informational frames. Next, students enhance their understanding by applying their knowledge in lab procedures, while also gaining familiarity with the use and power of a widely-used software package and scientific tool. No mathematical knowledge beyond basic algebra is required to complete the labs or to understand the computations in the spreadsheets, although the students are exposed to the concepts of numerical integration. The labs are contained in Excel workbook files. In the files are multiple spreadsheets, which contain either a frame with information on how to run the lab, material on the subject, or one or more procedures. Excel's VBA macro language is used to automate the labs. The macros are accessed through button interfaces positioned on the spreadsheets. This is done intentionally so that students can focus on learning the subject matter and the basic spreadsheet features without having to learn advanced Excel features all at once. Students open the file and progress through the informational frames to the procedures. After each procedure, student comments and data are automatically recorded in a preformatted Lab Report spreadsheet. Once all procedures have been completed, the student is prompted for a filename in which to save their Lab Report. The lab reports can then be printed or emailed to the instructor. The files will have full worksheet and workbook protection, and will have a "redo" feature at the end of the lab for students who want to repeat a procedure.
Okamura, Tomonori; Miura, Katsuyuki; Sawamura, Tatsuya; Kadota, Aya; Hisamatsu, Takashi; Fujiyoshi, Akira; Miyamatsu, Naomi; Takashima, Naoyuki; Miyagawa, Naoko; Kadowaki, Takashi; Ohkubo, Takayoshi; Murakami, Yoshitaka; Nakamura, Yasuyuki; Ueshima, Hirotsugu
2016-01-01
The serum level of LOX-1 ligand containing ApoB (LAB) may reflect atherogenicity better than usual lipid parameters; however, the relationship between LAB and carotid intima-media thickness (IMT) was not clear even in Asian populations. A total of 992 community-dwelling Japanese men, aged 40 to 79 years, were enrolled in the present study. Serum LAB levels were measured by enzyme-linked immunosorbent assays (ELISAs) with recombinant LOX-1 and monoclonal anti-apolipoprotein B antibody. Serum LAB levels (median [interquartile range], μg cs/L) were 5341 μg cs/L (4093-7125). The mean average IMT of the common carotid artery was highest in the fourth LAB quartile (842 μm) compared with the first quartile (797 μm) after adjustment for age, high-density lipoprotein cholesterol, triglyceride, body mass index, hypertension, diabetes, high sensitivity C-reactive protein, smoking, and alcohol drinking. However, this statistically significant difference was lost after further adjustment for total cholesterol (TC). After stratification using the combination of median LAB and hypercholesterolemia (serum TC ≥ 6.21 mmol/L and/or lipid-lowering medication), the adjusted mean average IMT (standard error) in the high LAB/hypercholesterolemia group was 886 μm (12.7), 856 μm (16.7) in the low LAB/hypercholesterolemia group, and 833 μm (8.4) in the low LAB/normal cholesterol group (P = .004). After further adjustment for TC, mean average IMT in the high LAB group was significantly higher than that measured in the low LAB group in hypercholesterolemic participants not taking lipid-lowering medication. Serum LAB was associated with an increased carotid IMT in Japanese men, especially those with hypercholesterolemia. Copyright © 2016 National Lipid Association. Published by Elsevier Inc. All rights reserved.
Reducing unnecessary lab testing in the ICU with artificial intelligence.
Cismondi, F; Celi, L A; Fialho, A S; Vieira, S M; Reti, S R; Sousa, J M C; Finkelstein, S N
2013-05-01
To reduce unnecessary lab testing by predicting when a proposed future lab test is likely to contribute information gain and thereby influence clinical management in patients with gastrointestinal bleeding. Recent studies have demonstrated that frequent laboratory testing does not necessarily relate to better outcomes. Data preprocessing, feature selection, and classification were performed and an artificial intelligence tool, fuzzy modeling, was used to identify lab tests that do not contribute an information gain. There were 11 input variables in total. Ten of these were derived from bedside monitor trends heart rate, oxygen saturation, respiratory rate, temperature, blood pressure, and urine collections, as well as infusion products and transfusions. The final input variable was a previous value from one of the eight lab tests being predicted: calcium, PTT, hematocrit, fibrinogen, lactate, platelets, INR and hemoglobin. The outcome for each test was a binary framework defining whether a test result contributed information gain or not. Predictive modeling was applied to recognize unnecessary lab tests in a real world ICU database extract comprising 746 patients with gastrointestinal bleeding. Classification accuracy of necessary and unnecessary lab tests of greater than 80% was achieved for all eight lab tests. Sensitivity and specificity were satisfactory for all the outcomes. An average reduction of 50% of the lab tests was obtained. This is an improvement from previously reported similar studies with average performance 37% by [1-3]. Reducing frequent lab testing and the potential clinical and financial implications are an important issue in intensive care. In this work we present an artificial intelligence method to predict the benefit of proposed future laboratory tests. Using ICU data from 746 patients with gastrointestinal bleeding, and eleven measurements, we demonstrate high accuracy in predicting the likely information to be gained from proposed future lab testing for eight common GI related lab tests. Future work will explore applications of this approach to a range of underlying medical conditions and laboratory tests. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Reducing unnecessary lab testing in the ICU with artificial intelligence
Cismondi, F.; Celi, L.A.; Fialho, A.S.; Vieira, S.M.; Reti, S.R.; Sousa, J.M.C.; Finkelstein, S.N.
2017-01-01
Objectives To reduce unnecessary lab testing by predicting when a proposed future lab test is likely to contribute information gain and thereby influence clinical management in patients with gastrointestinal bleeding. Recent studies have demonstrated that frequent laboratory testing does not necessarily relate to better outcomes. Design Data preprocessing, feature selection, and classification were performed and an artificial intelligence tool, fuzzy modeling, was used to identify lab tests that do not contribute an information gain. There were 11 input variables in total. Ten of these were derived from bedside monitor trends heart rate, oxygen saturation, respiratory rate, temperature, blood pressure, and urine collections, as well as infusion products and transfusions. The final input variable was a previous value from one of the eight lab tests being predicted: calcium, PTT, hematocrit, fibrinogen, lactate, platelets, INR and hemoglobin. The outcome for each test was a binary framework defining whether a test result contributed information gain or not. Patients Predictive modeling was applied to recognize unnecessary lab tests in a real world ICU database extract comprising 746 patients with gastrointestinal bleeding. Main results Classification accuracy of necessary and unnecessary lab tests of greater than 80% was achieved for all eight lab tests. Sensitivity and specificity were satisfactory for all the outcomes. An average reduction of 50% of the lab tests was obtained. This is an improvement from previously reported similar studies with average performance 37% by [1–3]. Conclusions Reducing frequent lab testing and the potential clinical and financial implications are an important issue in intensive care. In this work we present an artificial intelligence method to predict the benefit of proposed future laboratory tests. Using ICU data from 746 patients with gastrointestinal bleeding, and eleven measurements, we demonstrate high accuracy in predicting the likely information to be gained from proposed future lab testing for eight common GI related lab tests. Future work will explore applications of this approach to a range of underlying medical conditions and laboratory tests. PMID:23273628
Tang, Y; Saris, P E J
2013-10-01
Lactobacillus acidophilus LAB20 has potential to be a probiotic strain because it can be present at high numbers in the jejunum of dog. To specifically detect LAB20 from dog faecal samples, a real-time PCR protocol was developed targeting the novel surface (S) layer protein gene of LAB20. The presence of S-layer protein was verified by N-terminal sequencing of the approximately 50-kDa major band from SDS-PAGE gel. The corresponding S-layer gene was amplified by inverse PCR using homology to known S-layers and sequenced. This novel S-layer protein has low sequence similarity to other S-layer proteins in the N-terminal region (32-211 aa, 7-39%). This enabled designing strain-specific PCR primers. The primer set was utilized to study intestinal persistence of LAB20 in dog that was fed with LAB20 fermented milk for 5 days. The results showed that LAB20 can be detected from dog faecal sample after 6 weeks with 10(4·53) DNA copies g(-1) postadministration. It suggested that LAB20 could be a good candidate to study the mechanism behind its persistence and dominance in dog intestine and maybe utilize it as a probiotic for canine. A real-time PCR method was developed to detect Lactobacillus acidophilus LAB20, a strain that was previously found dominant in canine gastrointestinal (GI) tract. The quantitative detection was based on targeting to variation region of a novel S-layer protein found in LAB20, allowing to specifically enumerate LAB20 from dog faeces. The results showed that the real-time PCR method was sensitive enough to be used in later intervention studies. Interestingly, LAB20 was found to persist in dog GI tract for 6 weeks. Therefore, LAB20 could be a good candidate to study its colonization and potentially utilize as a canine probiotic. © 2013 The Society for Applied Microbiology.
Is This Real Life? Is This Just Fantasy?: Realism and Representations in Learning with Technology
NASA Astrophysics Data System (ADS)
Sauter, Megan Patrice
Students often engage in hands-on activities during science learning; however, financial and practical constraints often limit the availability of these activities. Recent advances in technology have led to increases in the use of simulations and remote labs, which attempt to recreate hands-on science learning via computer. Remote labs and simulations are interesting from a cognitive perspective because they allow for different relations between representations and their referents. Remote labs are unique in that they provide a yoked representation, meaning that the representation of the lab on the computer screen is actually linked to that which it represents: a real scientific device. Simulations merely represent the lab and are not connected to any real scientific devices. However, the type of visual representations used in the lab may modify the effects of the lab technology. The purpose of this dissertation is to examine the relation between representation and technology and its effects of students' psychological experiences using online science labs. Undergraduates participated in two studies that investigated the relation between technology and representation. In the first study, participants performed either a remote lab or a simulation incorporating one of two visual representations, either a static image or a video of the equipment. Although participants in both lab conditions learned, participants in the remote lab condition had more authentic experiences. However, effects were moderated by the realism of the visual representation. Participants who saw a video were more invested and felt the experience was more authentic. In a second study, participants performed a remote lab and either saw the same video as in the first study, an animation, or the video and an animation. Most participants had an authentic experience because both representations evoked strong feelings of presence. However, participants who saw the video were more likely to believe the remote technology was real. Overall, the findings suggest that participants' experiences with technology were shaped by representation. Students had more authentic experiences using the remote lab than the simulation. However, incorporating visual representations that enhance presence made these experiences even more authentic and meaningful than afforded by the technology alone.
2004-01-05
KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences Lab, Lanfang Levine, with Dynamac Corp., transfers material into a sample bottle for analysis. She is standing in front of new equipment in the lab that will provide gas chromatography and mass spectrometry. The equipment will enable analysis of volatile compounds, such as from plants. The 100,000 square-foot facility houses labs for NASA’s ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASA’s Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASA’s Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.
Koziel, Jacek A; Ahn, Heekwon; Glanville, Thomas D; Frana, Timothy S; van Leeuwen, J Hans; Nguyen, Lam T
2018-06-01
Nearly 55,000 outbreaks of animal disease were reported to the World Animal Health Information Database between 2005 and 2016. To suppress the spread of disease, large numbers of animal mortalities often must be disposed of quickly and are frequently buried on the farm where they were raised. While this method of emergency disposal is fast and relatively inexpensive, it also can have undesirable and lasting impacts (slow decay, concerns about groundwater contamination, pathogens re-emergence, and odor). Following the 2010 foot-and-mouth disease outbreak, the Republic of Korea's National Institute of Animal Science funded research on selected burial alternatives or modifications believed to have potential to reduce undesirable impacts of burial. One such modification involves the injection of air into the liquid degradation products from the 60-70% water from decomposing carcasses in lined burial trenches. Prior to prototype development in the field, a laboratory-scale study of aerated decomposition (AeD) of poultry carcasses was conducted to quantify improvements in time of carcass decomposition, reduction of potential groundwater pollutants in the liquid products of decomposition (since trench liners may ultimately leak), and reduction of odorous VOCs emitted during decomposition. Headspace gases also were monitored to determine the potential for using gaseous biomarkers in the aerated burial trench exhaust stream to monitor completion of the decomposition. Results of the lab-scale experiments show that the mass of chicken carcasses was reduced by 95.0 ± 0.9% within 3 months at mesophilic temperatures (vs. negligible reduction via mesophilic anaerobic digestion typical of trench burial) with concomitant reduction of biochemical oxygen demand (BOD; 99%), volatile suspended solids (VSS; 99%), total suspended solids (TSS; 99%), and total ammonia nitrogen (TAN; 98%) in the liquid digestate. At week #7 BOD and TSS in digestate met the U.S. EPA standards for treated wastewater discharge to surface water. Salmonella and Staphylococcus were inactivated by the AeD process after week #1 and #3, respectively. Five gaseous biomarkers: pyrimidine; p-cresol; phenol; dimethyl disulfide; and dimethyl trisulfide; were identified and correlated with digestate quality. Phenol was the best predictor of TAN (R = 0.96), BOD (R = 0.92), and dissolved oxygen (DO) (R = -0.91). Phenol was also the best predictor populations of Salmonella (R = 0.95) and aerobes (R = 0.88). P-cresol was the best predictor for anaerobes (R = 0.88). The off-gas from AeD will require biofiltration or other odor control measures for a much shorter time than anaerobic decomposition. The lab-scale studies indicate that AeD burial has the potential to make burial a faster, safer, and more environmentally friendly method for emergency disposal and treatment of infectious animal carcasses and that this method should be further developed via prototype-scale field studies. Copyright © 2018 Elsevier Ltd. All rights reserved.
Seeing an Old Lab in a New Light: Transforming a Traditional Optics Lab into Full Guided Inquiry
ERIC Educational Resources Information Center
Maley, Tim; Stoll, Will; Demir, Kadir
2013-01-01
This paper describes the authors' experiences transforming a "cookbook" lab into an inquiry-based investigation and the powerful effect the inquiry-oriented lab had on our students' understanding of lenses. We found the inquiry-oriented approach led to richer interactions between students as well as a deeper conceptual…
Problem Solvers: MathLab's Design Brings Professional Learning into the Classroom
ERIC Educational Resources Information Center
Morales, Sara; Sainz, Terri
2017-01-01
Imagine teachers, administrators, and university mathematicians and staff learning together in a lab setting where students are excited about attending a week-long summer math event because they are at the forefront of the experience. Piloted in three New Mexico classrooms during summer 2014, MathLab expanded into 17 lab settings over six…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-05
... allegations: ``* * * there was a contract between Xpedite and AppLabs, an Indian company to do customer... customers that need custom data transfers. Xpedite was also using AppLabs for migration work. AppLabs... of events: ``AppLabs completes SOW (SOW template) reviewed by SE before going to customer'' ``SOW...
ERIC Educational Resources Information Center
Williamson, Ben
2015-01-01
Policy innovation labs are emerging knowledge actors and technical experts in the governing of education. The article offers a historical and conceptual account of the organisational form of the policy innovation lab. Policy innovation labs are characterised by specific methods and techniques of design, data science, and digitisation in public…
Low Budget Biology 3: A Collection of Low Cost Labs and Activities.
ERIC Educational Resources Information Center
Wartski, Bert; Wartski, Lynn Marie
This document contains biology labs, demonstrations, and activities that use low budget materials. The goal is to get students involved in the learning process by experiencing biology. Each lab has a teacher preparation section which outlines the purpose of the lab, some basic information, a list of materials , and how to prepare the different…
Sustainable dual-use labs: neurovascular interventional capabilities within the cath lab.
Lang, Stacey
2012-01-01
The inclusion of neurovascular interventional capabilities within the cath lab setting can be key to optimal utilization of resources, increased staff efficiency, and streamlined operations. When considering an expansion, look beyond the patient population traditionally associated with cardiac cath labs and consider the integration of programs outside cardiac alone--to create a true dual-use lab space. With proper planning, quality dual purpose equipment, appropriately trained staff, capable physicians, and strong leadership, an organization willing to embrace the challenge can build a truly extraordinary service.
NASA Astrophysics Data System (ADS)
Olney, Dave
1997-11-01
This paper offers some suggestions on making lab work for high school chemistry students more productive, with students taking an active role. They include (1) rewriting labs from manuals to better suit one's purpose, (2) the questionable use of canned data tables, (3) designing microscale labs that utilize its unique features, such as safety and ease of repetition, (4) having students actually carry out experimental design on occasion, using a model from PRACTICE IN THINKING, and (5) using comuters/calculators in the lab in meaningful ways. Many examples feature discovery-type labs the author has developed over the years.
EPICS Channel Access Server for LabVIEW
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhukov, Alexander P.
It can be challenging to interface National Instruments LabVIEW (http://www.ni.com/labview/) with EPICS (http://www.aps.anl.gov/epics/). Such interface is required when an instrument control program was developed in LabVIEW but it also has to be part of global control system. This is frequently useful in big accelerator facilities. The Channel Access Server is written in LabVIEW, so it works on any hardware/software platform where LabVIEW is available. It provides full server functionality, so any EPICS client can communicate with it.
Implementation of the Web-based laboratory
NASA Astrophysics Data System (ADS)
Ying, Liu; Li, Xunbo
2005-12-01
With the rapid developments of Internet technologies, remote access and control via Internet is becoming a reality. A realization of the web-based laboratory (the W-LAB) was presented. The main target of the W-LAB was to allow users to easily access and conduct experiments via the Internet. While realizing the remote communication, a system, which adopted the double client-server architecture, was introduced. It ensures the system better security and higher functionality. The experimental environment implemented in the W-Lab was integrated by both virtual lab and remote lab. The embedded technology in the W-LAB system as an economical and efficient way to build the distributed infrastructural network was introduced. Furthermore, by introducing the user authentication mechanism in the system, it effectively secures the remote communication.
Genomics of lactic acid bacteria: Current status and potential applications.
Wu, Chongde; Huang, Jun; Zhou, Rongqing
2017-08-01
Lactic acid bacteria (LAB) are widely used for the production of a variety of foods and feed raw materials where they contribute to flavor and texture of the fermented products. In addition, specific LAB strains are considered as probiotic due to their health-promoting effects in consumers. Recently, the genome sequencing of LAB is booming and the increased amount of published genomics data brings unprecedented opportunity for us to reveal the important traits of LAB. This review describes the recent progress on LAB genomics and special emphasis is placed on understanding the industry-related physiological features based on genomics analysis. Moreover, strategies to engineer metabolic capacity and stress tolerance of LAB with improved industrial performance are also discussed.
Bayer, Chris N; Luberda, Michael
2016-01-01
Incomprehension and denial of the theory of evolution among high school students has been observed to also occur when teachers are not equipped to deliver a compelling case also for human evolution based on fossil evidence. This paper assesses the outcomes of a novel inquiry-based paleoanthropology lab teaching human evolution to high-school students. The inquiry-based Be a Paleoanthropologist for a Day lab placed a dozen hominin skulls into the hands of high-school students. Upon measuring three variables of human evolution, students explain what they have observed and discuss findings. In the 2013/14 school year, 11 biology classes in 7 schools in the Greater New Orleans area participated in this lab. The interviewed teacher cohort unanimously agreed that the lab featuring hominin skull replicas and stimulating student inquiry was a pedagogically excellent method of delivering the subject of human evolution. First, the lab's learning path of transforming facts to data, information to knowledge, and knowledge to acceptance empowered students to themselves execute part of the science that underpins our understanding of deep time hominin evolution. Second, although challenging, the hands-on format of the lab was accessible to high-school students, most of whom were readily able to engage the lab's scientific process. Third, the lab's exciting and compelling pedagogy unlocked higher order thinking skills, effectively activating the cognitive, psychomotor and affected learning domains as defined in Bloom's taxonomy. Lastly, the lab afforded students a formative experience with a high degree of retention and epistemic depth. Further study is warranted to gauge the degree of these effects.
My Green Car: The Adventure Begins (Ep. 1) â DOE Lab-Corps Video Series
Saxena, Samveg; Shah, Nihar; Hansen, Dana
2018-06-12
One key difference between a great technology that stays in the lab and one that reaches the marketplace is customer interest. In Episode 1, the Labâs MyGreenCar team gets ready to step outside the lab and test their technologyâs value to consumers in a scientific way. What makes a new technology compelling enough to transition out of the lab and become a consumer product? Thatâs the question Berkeley Lab researchers Samveg Saxena, Nihar Shah, and Dana Hansen plus industry mentor Russell Carrington set out to answer for MyGreenCar, an app providing personalized fuel economy or electric vehicle range estimates for consumers researching new cars. DOEâs Lab-Corps program offered the technology team some answers. The EERE-funded program, based on the National Science Foundationâs I-Corps⢠model for entrepreneurial training, provides tools and training to move energy-related inventions to the marketplace. During Lab-Corpâs intensive six-week session, technology teams interview 100 customer and value chain members to discover which potential products based on their technologies will have significant market pull. A six video series follows the MyGreenCar teamâs Lab-Corps experience, from pre-training preparation with the Labâs Innovation and Partnerships Office through the ups and downs of the customer discovery process. Will the app make it to the marketplace? Youâll just have to watch.
Vihavainen, Elina; Lundström, Hanna-Saara; Susiluoto, Tuija; Koort, Joanna; Paulin, Lars; Auvinen, Petri; Björkroth, K. Johanna
2007-01-01
Some psychrotrophic lactic acid bacteria (LAB) are specific meat spoilage organisms in modified-atmosphere-packaged (MAP), cold-stored meat products. To determine if incoming broilers or the production plant environment is a source of spoilage LAB, a total of 86, 122, and 447 LAB isolates from broiler carcasses, production plant air, and MAP broiler products, respectively, were characterized using a library of HindIII restriction fragment length polymorphism (RFLP) patterns of the 16 and 23S rRNA genes as operational taxonomic units in numerical analyses. Six hundred thirteen LAB isolates from the total of 655 clustered in 29 groups considered to be species specific. Sixty-four percent of product isolates clustered either with Carnobacterium divergens or with Carnobacterium maltaromaticum type strains. The third major product-associated cluster (17% of isolates) was formed by unknown LAB. Representative strains from these three clusters were analyzed for the phylogeny of their 16S rRNA genes. This analysis verified that the two largest RFLP clusters consisted of carnobacteria and showed that the unknown LAB group consisted of Lactococcus spp. No product-associated LAB were detected in broiler carcasses sampled at the beginning of slaughter, whereas carnobacteria and lactococci, along with some other specific meat spoilage LAB, were recovered from processing plant air at many sites. This study reveals that incoming broiler chickens are not major sources of psychrotrophic spoilage LAB, whereas the detection of these organisms from the air of the processing environment highlights the role of processing facilities as sources of LAB contamination. PMID:17142357
NASA Astrophysics Data System (ADS)
Jones, Barbara
2001-03-01
At UCSD biology majors are required to take 3 quarters of a calculus based physics course. This is taught in a standard format large lecture class partly by faculty and partly by freeway flyers. We are working with physics graduate students who are also participating in our PFPF (Preparing Future Physics Faculty) program to write, review, and teach new weekly labs for these biology students. This provides an experience for the grad student that is both rewarding to them and useful to the department. The grad students participate in curriculum development, they observe the students behaviour in the labs, and assess the effectiveness of different lab formats. The labs are intended to provide an interactive, hands on experience with a wide variety of equipment which is mostly both simple and inexpensive. Both students and grads find the labs to be engaging and fun. Based on group discussions the labs are modified to try to try to create the best teaching environment. The biology students benefit from the improvements both in the quality of the labs they do, and from the enthusiasm of the TAs who take an active interest in their learning. The ability to make significant changes to the material taught maintains the interest of the grad students and helps to make the labs a stable and robust environment.
NASA Astrophysics Data System (ADS)
Stanley, Jacob T.; Lewandowski, H. J.
2016-12-01
In experimental physics, lab notebooks play an essential role in the research process. For all of the ubiquity of lab notebooks, little formal attention has been paid to addressing what is considered "best practice" for scientific documentation and how researchers come to learn these practices in experimental physics. Using interviews with practicing researchers, namely, physics graduate students, we explore the different experiences researchers had in learning how to effectively use a notebook for scientific documentation. We find that very few of those interviewed thought that their undergraduate lab classes successfully taught them the benefit of maintaining a lab notebook. Most described training in lab notebook use as either ineffective or outright missing from their undergraduate lab course experience. Furthermore, a large majority of those interviewed explained that they did not receive any formal training in maintaining a lab notebook during their graduate school experience and received little to no feedback from their advisors on these records. Many of the interviewees describe learning the purpose of, and how to maintain, these kinds of lab records only after having a period of trial and error, having already started doing research in their graduate program. Despite the central role of scientific documentation in the research enterprise, these physics graduate students did not gain skills in documentation through formal instruction, but rather through informal hands-on practice.
ERIC Educational Resources Information Center
Parent, Beth A.; Marbach-Ad, Gili; Swanson, Karen V.; Smith, Ann C.
2010-01-01
Scientific literature was used to give a research oriented context to our immunology lab course. Immunology lab, a senior level course (60 students/year) was formerly taught in a traditional mode, with exercises aimed at learning lab protocols. To engage students in understanding we connected the protocols to their use as reported in research…
Extreme Environments Test Capabilities at NASA GRC for Parker Hannifin Visit
NASA Technical Reports Server (NTRS)
Arnett, Lori
2016-01-01
The presentation includes general description on the following test facilities: Fuel Cell Testing Lab, Structural Dynamics Lab, Thermal Vacuum Test Facilities - including a description of the proposed Kinetic High Altitude Simulator concept, EMI Test Lab, and the Creek Road Cryogenic Complex - specifically the Small Multi-purpose Research Facility (SMiRF) and the Cryogenics Components Lab 7 (CCL-7).
ERIC Educational Resources Information Center
Moore, Randy; Jensen, Philip A.
2008-01-01
Science courses with hands-on investigative labs are a typical part of the general education requirements at virtually all colleges and universities. In these courses, labs that satisfy a curricular requirement for "lab experience" are important because they provide the essence of the scientific experience--that is, they give students…
ERIC Educational Resources Information Center
Holmes, N. G.; Olsen, Jack; Thomas, James L.; Wieman, Carl E.
2017-01-01
Instructional labs are widely seen as a unique, albeit expensive, way to teach scientific content. We measured the effectiveness of introductory lab courses at achieving this educational goal across nine different lab courses at three very different institutions. These institutions and courses encompassed a broad range of student populations and…
Validity of Selected Lab and Field Tests of Physical Working Capacity.
ERIC Educational Resources Information Center
Burke, Edmund J.
The validity of selected lab and field tests of physical working capacity was investigated. Forty-four male college students were administered a series of lab and field tests of physical working capacity. Lab tests include a test of maximum oxygen uptake, the PWC 170 test, the Harvard Step Test, the Progressive Pulse Ratio Test, Margaria Test of…
Behind the Scenes at Berkeley Lab - The Mechanical Fabrication Facility
Wells, Russell; Chavez, Pete; Davis, Curtis; Bentley, Brian
2018-04-16
Part of the Behind the Scenes series at Berkeley Lab, this video highlights the lab's mechanical fabrication facility and its exceptional ability to produce unique tools essential to the lab's scientific mission. Through a combination of skilled craftsmanship and precision equipment, machinists and engineers work with scientists to create exactly what's needed - whether it's measured in microns or meters.
Koo, Ok-Kyung; Eggleton, Mallory; O'Bryan, Corliss A; Crandall, Philip G; Ricke, Steven C
2012-12-01
Contamination by Listeria monocytogenes has been a constant public health threat for the ready-to-eat (RTE) meat industry due to the potential for high mortalities from listeriosis. Lactic acid bacteria (LAB) have shown protective action against various pathogenic bacteria. The aim of this study was to evaluate the antilisterial activity of a combination of three LAB strains (Lactiguard®) on L. monocytogenes. The combination of the LAB was inhibitory to L. monocytogenes inoculated onto frankfurters not containing lactate/diacetate after 8weeks of refrigerated storage (0.6 log reduction compared to L. monocytogenes only control), and when a cell free extract (CFS) of the LAB was added with LAB even more inhibition was obtained (1.2 log reduction compared with L. monocytogenes only). In frankfurters containing lactate/diacetate the LAB and the LAB plus CFS were more effective in reducing growth of L. monocytogenes after 8 weeks of refrigerated storage (2 and 3.3 log reductions respectively). Copyright © 2012 Elsevier Ltd. All rights reserved.
The experiment editor: supporting inquiry-based learning with virtual labs
NASA Astrophysics Data System (ADS)
Galan, D.; Heradio, R.; de la Torre, L.; Dormido, S.; Esquembre, F.
2017-05-01
Inquiry-based learning is a pedagogical approach where students are motivated to pose their own questions when facing problems or scenarios. In physics learning, students are turned into scientists who carry out experiments, collect and analyze data, formulate and evaluate hypotheses, and so on. Lab experimentation is essential for inquiry-based learning, yet there is a drawback with traditional hands-on labs in the high costs associated with equipment, space, and maintenance staff. Virtual laboratories are helpful to reduce these costs. This paper enriches the virtual lab ecosystem by providing an integrated environment to automate experimentation tasks. In particular, our environment supports: (i) scripting and running experiments on virtual labs, and (ii) collecting and analyzing data from the experiments. The current implementation of our environment supports virtual labs created with the authoring tool Easy Java/Javascript Simulations. Since there are public repositories with hundreds of freely available labs created with this tool, the potential applicability to our environment is considerable.
Numerical and experimental study of liquid breakup process in solid rocket motor nozzle
NASA Astrophysics Data System (ADS)
Yen, Yi-Hsin
Rocket propulsion is an important travel method for space exploration and national defense, rockets needs to be able to withstand wide range of operation environment and also stable and precise enough to carry sophisticated payload into orbit, those engineering requirement makes rocket becomes one of the state of the art industry. The rocket family have been classified into two major group of liquid and solid rocket based on the fuel phase of liquid or solid state. The solid rocket has the advantages of simple working mechanism, less maintenance and preparing procedure and higher storage safety, those characters of solid rocket make it becomes popular in aerospace industry. Aluminum based propellant is widely used in solid rocket motor (SRM) industry due to its avalibility, combusion performance and economical fuel option, however after aluminum react with oxidant of amonimum perchrate (AP), it will generate liquid phase alumina (Al2O3) as product in high temperature (2,700˜3,000 K) combustion chamber enviornment. The liquid phase alumina particles aggromorate inside combustion chamber into larger particle which becomes major erosion calprit on inner nozzle wall while alumina aggromorates impinge on the nozzle wall surface. The erosion mechanism result nozzle throat material removal, increase the performance optimized throat diameter and reduce nozzle exit to throat area ratio which leads to the reduction of exhaust gas velocity, Mach number and lower the propulsion thrust force. The approach to avoid particle erosion phenomenon taking place in SRM's nozzle is to reduce the alumina particle size inside combustion chamber which could be done by further breakup of the alumina droplet size in SRM's combustion chamber. The study of liquid breakup mechanism is an important means to smaller combustion chamber alumina droplet size and mitigate the erosion tack place on rocket nozzle region. In this study, a straight two phase air-water flow channel experiment is set up for liquid breakup phenomenon observation. The liquid water material in this experiment will play a comparison role as liquid alumina in high temerature enviornment. The method proposed to control the liquid breakup size of liquid droplet is done by the means of changing the liquid properties of surface tension. The surface tenion of liquid plays an inportant role of providing major liquid droplet bounding pressure or Laplace pressure. By reduceing surface tension of liquid leads to lower Laplace pressure of droplet and result in less droplet dynamic stability which could be breakup under external pressure difference. The reduction of surface tension of liquid aluminum could be achieved by adding magnisium and strontium, it is reported that the surface tension reeducation level could reach 10%˜15% when those additive mension above are adding to aluminum. This study of liquid breakup mechanism include two major part, first part is straight two-phase channel experiment and simulation comparison which provide a validation work of CFD simulation performance when compare to experiment. Second part is single droplet breakup experiment, in this experiment the relation of surface tension and liquid breakup behavior is carefully studied. The straight two-phase flow channel experiment setting will enable to us to study the liquid breakup process in macro scale. The quantification method is achieved by analyzing high-speed camera image by MatLab image process code develop in UW-Milwaukee wind tunnel lab which extract data in images and provide information including liquid droplet count and size distribution, wave frequency and time averaging two-phase free boundary. It was found that liquid breakup mechanism proportional to gas-droplet velocity difference square, gas density and liquid droplet size and inverse proportional to liquid surface tension. The single droplet experiment part is provide a close up view of liquid breakup and prove the reduced surface tension will enhance liquid breakup activity. In this study, we could observe the evidence of enhance liquid breakup activity by the reduced surface tension of liquid. Therefor the approach of reducing surface tension of Solid Rocket Motor (SRM) fuel reacting product is a high potential solution to SRM nozzle erosion.
Computational Labs Using VPython Complement Conventional Labs in Online and Regular Physics Classes
NASA Astrophysics Data System (ADS)
Bachlechner, Martina E.
2009-03-01
Fairmont State University has developed online physics classes for the high-school teaching certificate based on the text book Matter and Interaction by Chabay and Sherwood. This lead to using computational VPython labs also in the traditional class room setting to complement conventional labs. The computational modeling process has proven to provide an excellent basis for the subsequent conventional lab and allows for a concrete experience of the difference between behavior according to a model and realistic behavior. Observations in the regular class room setting feed back into the development of the online classes.
NASA Technical Reports Server (NTRS)
Norbury, John W.; Blattnig, Steve R.
2008-01-01
Space radiation transport codes require accurate models for hadron production in intermediate energy nucleus-nucleus collisions. Codes require cross sections to be written in terms of lab frame variables and it is important to be able to verify models against experimental data in the lab frame. Several models are compared to lab frame data. It is found that models based on algebraic parameterizations are unable to describe intermediate energy differential cross section data. However, simple thermal model parameterizations, when appropriately transformed from the center of momentum to the lab frame, are able to account for the data.
Pynaert, Kris; Smets, Barth F.; Wyffels, Stijn; Beheydt, Daan; Siciliano, Steven D.; Verstraete, Willy
2003-01-01
In this study, a lab-scale rotating biological contactor (RBC) treating a synthetic NH4+ wastewater devoid of organic carbon and showing high N losses was examined for several important physiological and microbial characteristics. The RBC biofilm removed 89% ± 5% of the influent N at the highest surface load of approximately 8.3 g of N m−2 day−1, with N2 as the main end product. In batch tests, the RBC biomass showed good aerobic and anoxic ammonium oxidation (147.8 ± 7.6 and 76.5 ± 6.4 mg of NH4+-N g of volatile suspended solids [VSS]−1 day−1, respectively) and almost no nitrite oxidation (< 1 mg of N g of VSS−1 day−1). The diversity of aerobic ammonia-oxidizing bacteria (AAOB) and planctomycetes in the biofilm was characterized by cloning and sequencing of PCR-amplified partial 16S rRNA genes. Phylogenetic analysis of the clones revealed that the AAOB community was fairly homogeneous and was dominated by Nitrosomonas-like species. Close relatives of the known anaerobic ammonia-oxidizing bacterium (AnAOB) Kuenenia stuttgartiensis dominated the planctomycete community and were most probably responsible for anoxic ammonium oxidation in the RBC. Use of a less specific planctomycete primer set, not amplifying the AnAOB, showed a high diversity among other planctomycetes, with representatives of all known groups present in the biofilm. The spatial organization of the biofilm was characterized using fluorescence in situ hybridization (FISH) with confocal scanning laser microscopy (CSLM). The latter showed that AAOB occurred side by side with putative AnAOB (cells hybridizing with probe PLA46 and AMX820/KST1275) throughout the biofilm, while other planctomycetes hybridizing with probe PLA886 (not detecting the known AnAOB) were present as very conspicuous spherical structures. This study reveals that long-term operation of a lab-scale RBC on a synthetic NH4+ wastewater devoid of organic carbon yields a stable biofilm in which two bacterial groups, thought to be jointly responsible for the high autotrophic N removal, occur side by side throughout the biofilm. PMID:12788771
NASA Technical Reports Server (NTRS)
James, John T.
2003-01-01
The toxicological assessments of grab sample canisters (GSCs) and 2 solid sorbent air samplers (SSASs) returned aboard STS-111 are reported. Analytical methods have not changed from earlier reports. Surrogate standard recoveries from the GSCs were 86-106% and 62% to 136 % from the SSASs; 2 tubes with low surrogate recoveries were not reported. Pressure tracking indicated no leaks in the canisters during analysis. Recoveries from lab and trip controls for formaldehyde analyses ranged from 87 to 96%. The two general criteria used to assess air quality are the total-non-methane-volatile organic hydrocarbons (NMVOCs) and the total T-value (minus the CO2 and formaldehyde contributions). Because of the inertness of Freon 218 (octafluoropropane, OFP), Its contribution to the NMVOC is subtracted and tabulated separately. Control of atmospheric alcohols is important to the water recovery system engineers, hence total alcohols (including acetone) are also shown for each sample. Because formaldehyde is quantified from sorbent badges, its concentration is listed separately. The table shows that the air quality in general was acceptable for crew respiration; however, certain values shown in bold require further explanation. The 1.05 T value on 2/28/02 was caused by an unusually high measurement ofhexamethylcyc1otrisiloxane (T value = 0.50), which is not a concern. The MPLM T value of 1.42 and the alcohol level of 7.5 mg/cu m were due to an overall polluted atmosphere, which was expected at first entry. The major T-value component was carbon monoxide at a contribution of 0.44 units. Since the crew was only exposed momentarily to the polluted atmosphere, no health effects are expected. The formaldehyde value of 0.060 mg/cu m found in the Lab sample from 3/27/02 is cause for concern because the Lab consistently shows higher concentrations of formaldehyde than the SM and occasionally the concentrations are above the acceptable guideline. Levels of OFP have remained low, suggesting that no further leaks of the SM air conditioner have occurred.
Morello, Luca; Cossu, Raffaello; Raga, Roberto; Pivato, Alberto; Lavagnolo, Maria Cristina
2016-10-01
Leachate treatment is a major issue in the context of landfill management, particularly in view of the consistent changes manifested over time in the quality and quantity of leachate produced, linked to both waste and landfill characteristics, which renders the procedure technically difficult and expensive. Leachate recirculation may afford a series of potential advantages, including improvement of leachate quality, enhancement of gas production, acceleration of biochemical processes, control of moisture content, as well as nutrients and microbe migration within the landfill. Recirculation of the products of leachate treatment, such as reverse osmosis (RO) concentrate, is a less common practice, with widespread controversy relating to its suitability, potential impacts on landfill management and future gaseous and leachable emissions. Scientific literature provides the results of only a few full-scale applications of concentrate recirculation. In some cases, an increase of COD and ammonium nitrogen in leachate was observed, coupled with an increase of salinity; which, additionally, might negatively affect performance of the RO plant itself. In other cases, not only did leachate production not increase significantly but the characteristics of leachate extracted from the well closest to the re-injection point also remained unchanged. This paper presents the results of lab-scale tests conducted in landfill simulation reactors, in which the effects of injection of municipal solid waste (MSW) landfill leachate RO concentrate were evaluated. Six reactors were managed with different weekly concentrate inputs, under both anaerobic and aerobic conditions, with the aim of investigating the short and long-term effects of this practice on landfill emissions. Lab-scale tests resulted in a more reliable identification of compound accumulation and kinetic changes than full-scale applications, further enhancing the development of a mass balance in which gaseous emissions and waste characteristics were also taken into consideration. Results showed that RO concentrate recirculation did not produce consistent changes in COD emissions and methane production. Simultaneously, ammonium ion showed a consistent increase in leachate (more than 25%) in anaerobic reactors, free ammonia gaseous emissions doubled with concentrate injection, while chloride resulted accumulated inside the reactor. Copyright © 2016 Elsevier Ltd. All rights reserved.
Monitoring of wheat lactic acid bacteria from the field until the first step of dough fermentation.
Alfonzo, Antonio; Miceli, Claudia; Nasca, Anna; Franciosi, Elena; Ventimiglia, Giusi; Di Gerlando, Rosalia; Tuohy, Kieran; Francesca, Nicola; Moschetti, Giancarlo; Settanni, Luca
2017-04-01
The present work was carried out to retrieve the origin of lactic acid bacteria (LAB) in sourdough. To this purpose, wheat LAB were monitored from ear harvest until the first step of fermentation for sourdough development. The influence of the geographical area and variety on LAB species/strain composition was also determined. The ears of four Triticum durum varieties (Duilio, Iride, Saragolla and Simeto) were collected from several fields located within the Palermo province (Sicily, Italy) and microbiologically investigated. In order to trace the transfer of LAB during the consecutive steps of manipulation, ears were transformed aseptically and, after threshing, milling and fermentation, samples of kernels, semolinas and doughs, respectively, were analysed. LAB were not found to dominate the microbial communities of the raw materials. In general, kernels harboured lower levels of microorganisms than ears and ears than semolinas. Several samples showing no development of LAB colonies acidified the enrichment broth suggesting the presence of LAB below the detection limit. After fermentation, LAB loads increased consistently for all doughs, reaching levels of 7.0-7.5 Log CFU/g on M17. The values of pH (5.0) and TTA (5.6 mL NaOH/10 g of dough) indicated the occurrence of the acidification process for several doughs. LAB were phenotypically and genotypically differentiated by randomly amplified polymorphic DNA (RAPD)-PCR into eight groups including 51 strains belonging to the species Lactobacillus brevis, Lactobacillus coryniformis, Lactobacillus plantarum, Lactococcus lactis, Lactococcus garvieae, Enterococcus casseliflavus, Enterococcus faecium, Leuconostoc citreum, and Pediococcus pentosaceus. Lactobacilli constituted a minority the LAB community, while lactococci represented more than 50% of strains. Lower LAB complexity was found on kernels, while a richer biodiversity was observed in semolinas and fermented doughs. For broader microbiota characterisation in doughs before fermentation, the 16S rRNA gene fragment profiling was conducted on the unfermented doughs using MiSeq Illumina. LAB group was represented by Enterococcus, Lactococcus and members of Leuconostocaceae family whose relative abundances differed according to both geographical area and variety of wheat. The culture-independent approach confirmed that pediococci and lactobacilli constituted low abundance members of the semolina LAB microbiota and that although some strains may pass from wheat ear to fermented doughs, most are likely to come from other sources. Copyright © 2016 Elsevier Ltd. All rights reserved.
Contact angle hysteresis and oil film lubrication in electrowetting with two immiscible liquids
NASA Astrophysics Data System (ADS)
Gao, J.; Mendel, N.; Dey, R.; Baratian, D.; Mugele, F.
2018-05-01
Electrowetting (EW) of water drops in ambient oil has found a wide range of applications including lab-on-a-chip devices, display screens, and variable focus lenses. The efficacy of all these applications is dependent on the contact angle hysteresis (CAH), which is generally reduced in the presence of ambient oil due to thin lubrication layers. While it is well-known that AC voltage reduces the effective contact angle hysteresis (CAH) for EW in ambient air, we demonstrate here that CAH for EW in ambient oil increases with increasing AC and DC voltage. Taking into account the disjoining pressure of the fluoropolymer-oil-water system, short range chemical interactions, viscous oil entrainment, and electrostatic stresses, we find that this observation can be explained by progressive thinning of the oil layer underneath the drop with increasing voltage. This exposes the droplet to the roughness of the underlying solid and thereby increases hysteresis.
Salatino, Piero; Sannia, Giovanni
2014-01-01
In the present study, a crude laccase preparation from Pleurotus ostreatus was successfully immobilized on perlite, a cheap porous silica material, and tested for Remazol Brilliant Blue R (RBBR) decolourisation in a fluidized bed recycle reactor. Results showed that RBBR decolourisation is mainly due to enzyme action despite the occurrence of dye adsorption-related enzyme inhibition. Fine tuning of immobilization conditions allowed balancing the immobilization yield and the resulting rate of decolourisation, with the adsorption capacity of the solid biocatalyst. In the continuous lab scale reactor, a maximum conversion degree of 56.1% was achieved at reactor space-time of 4.2 h. Stability and catalytic parameters of the immobilized laccases were also assessed in comparison with the soluble counterparts, revealing an increase in stability, despite a reduction of the catalytic performances. Both effects are most likely ascribable to the occurrence of multipoint attachment phenomena. PMID:24895564
Energy saving achieved by limited filamentous bulking sludge under low dissolved oxygen.
Guo, Jian-Hua; Peng, Yong-Zhen; Peng, Cheng-Yao; Wang, Shu-Ying; Chen, Ying; Huang, Hui-Jun; Sun, Zhi-Rong
2010-02-01
Limited filamentous bulking caused by low dissolved oxygen (DO) was proposed to establish a low energy consumption wastewater treatment system. This method for energy saving was derived from two full-scale field observations, which showed pollutants removal would be enhanced and energy consumption could be reduced by at least 10% using limited filamentous bulking. Furthermore, preliminary investigation including the abundance evaluation and the identification of filamentous bacteria demonstrated that the limited filamentous bulking could be repeated steadily in a lab-scale anoxic-oxic reactor fed with domestic wastewater. The sludge loss did not occur in the secondary clarifier, while COD and total nitrogen removal efficiencies were improved by controlling DO for optimal filamentous bacterial population. Suspended solids in effluent were negligible and turbidity was lower than 2 NTU, which were distinctly lower than those under no bulking. Theoretical and experimental results indicated the aeration consumption could be saved by the application of limited filamentous bulking.
A 2.5D Computational Method to Simulate Cylindrical Fluidized Beds
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Tingwen; Benyahia, Sofiane; Dietiker, Jeff
2015-02-17
In this paper, the limitations of axisymmetric and Cartesian two-dimensional (2D) simulations of cylindrical gas-solid fluidized beds are discussed. A new method has been proposed to carry out pseudo-two-dimensional (2.5D) simulations of a cylindrical fluidized bed by appropriately combining computational domains of Cartesian 2D and axisymmetric simulations. The proposed method was implemented in the open-source code MFIX and applied to the simulation of a lab-scale bubbling fluidized bed with necessary sensitivity study. After a careful grid study to ensure the numerical results are grid independent, detailed comparisons of the flow hydrodynamics were presented against axisymmetric and Cartesian 2D simulations. Furthermore,more » the 2.5D simulation results have been compared to the three-dimensional (3D) simulation for evaluation. This new approach yields better agreement with the 3D simulation results than with axisymmetric and Cartesian 2D simulations.« less
The STS-98 crew poses for group photo near top of FSS
NASA Technical Reports Server (NTRS)
2001-01-01
KENNEDY SPACE CENTER, Fla. -- The STS-98 crew poses for a group photo on the 215-foot level of the Fixed Service Structure at Launch Pad 39A. Dressed in their orange launch and entry suits are (left to right) Commander Ken Cockrell, Mission Specialist Marsha Ivins, Pilot Mark Polansky and Mission Specialists Robert Curbeam and Thomas Jones. Behind them can be seen the white nose cone of a solid rocket booster and the orange external tank on Space Shuttle Atlantis. The crew is taking part in emergency egress training and a simulated launch countdown as part of Terminal Countdown Demonstration Test activities. STS-98 is the seventh construction flight to the International Space Station, carrying as payload the U.S. Lab Destiny, a key element in the construction of the ISS. Launch of STS-98 is scheduled for Jan. 19 at 2:11 a.m. EST.
Fuzzy logic feedback control for fed-batch enzymatic hydrolysis of lignocellulosic biomass.
Tai, Chao; Voltan, Diego S; Keshwani, Deepak R; Meyer, George E; Kuhar, Pankaj S
2016-06-01
A fuzzy logic feedback control system was developed for process monitoring and feeding control in fed-batch enzymatic hydrolysis of a lignocellulosic biomass, dilute acid-pretreated corn stover. Digested glucose from hydrolysis reaction was assigned as input while doser feeding time and speed of pretreated biomass were responses from fuzzy logic control system. Membership functions for these three variables and rule-base were created based on batch hydrolysis data. The system response was first tested in LabVIEW environment then the performance was evaluated through real-time hydrolysis reaction. The feeding operations were determined timely by fuzzy logic control system and efficient responses were shown to plateau phases during hydrolysis. Feeding of proper amount of cellulose and maintaining solids content was well balanced. Fuzzy logic proved to be a robust and effective online feeding control tool for fed-batch enzymatic hydrolysis.
Iranmanesh, M; Hulliger, J
2017-10-02
The use of strong magnetic field gradients and high magnetic fields generated by permanent magnets or superconducting coils has found applications in many fields such as mining, solid state chemistry, biochemistry and medical research. Lab scale or industrial implementations involve separation of macro- and nanoparticles, cells, proteins, and macromolecules down to small molecules and ions. Most promising are those attempts where the object to be separated is attached to a strong magnetic nanoparticle. Here, all kinds of specific affinity interactions are used to attach magnetic carrier particles to mainly objects of biological interest. Other attempts use a strong paramagnetic suspension for the separation of purely diamagnetic objects, such as bio-macromolecules or heavy metals. The application of magnetic separation to superconducting inorganic phases is of particular interest in combination with ceramic combinatorial chemistry to generate a library of e.g. cuprate superconductors.
Neto, A I; Correia, C R; Oliveira, M B; Rial-Hermida, M I; Alvarez-Lorenzo, C; Reis, R L; Mano, J F
2015-04-01
We propose a novel hanging spherical drop system for anchoring arrays of droplets of cell suspension based on the use of biomimetic superhydrophobic flat substrates, with controlled positional adhesion and minimum contact with a solid substrate. By facing down the platform, it was possible to generate independent spheroid bodies in a high throughput manner, in order to mimic in vivo tumour models on the lab-on-chip scale. To validate this system for drug screening purposes, the toxicity of the anti-cancer drug doxorubicin in cell spheroids was tested and compared to cells in 2D culture. The advantages presented by this platform, such as feasibility of the system and the ability to control the size uniformity of the spheroid, emphasize its potential to be used as a new low cost toolbox for high-throughput drug screening and in cell or tissue engineering.
NASA Astrophysics Data System (ADS)
Wang, Wei; Liu, Huiming; Huang, Rongjin; Zhao, Yuqiang; Huang, Chuangjun; Guo, Shibin; Shan, Yi; Li, Laifeng
2018-03-01
Thermal expansion and magnetostriction, the strain responses of a material to temperature and a magnetic field, especially properties at low temperature, are extremely useful to study electronic and phononic properties, phase transitions, quantum criticality, and other interesting phenomena in cryogenic engineering and materials science. However, traditional dilatometers cannot provide magnetic field and ultra low temperature (<77 K) environment easily. This paper describes the design and test results of thermal expansion and magnetostriction at cryogenic temperature using the strain gage method based on a Physical Properties Measurements System (PPMS). The interfacing software and automation were developed using LabVIEW. The sample temperature range can be tuned continuously between 1.8 K and 400 K. With this PPMS-aided measuring system, we can observe temperature and magnetic field dependence of the linear thermal expansion of different solid materials easily and accurately.
Co-composting of green waste and food waste at low C/N ratio
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kumar, Mathava; Ou, Y.-L.; Lin, J.-G., E-mail: jglin@mail.nctu.edu.t
2010-04-15
In this study, co-composting of food waste and green waste at low initial carbon to nitrogen (C/N) ratios was investigated using an in-vessel lab-scale composting reactor. The central composite design (CCD) and response surface method (RSM) were applied to obtain the optimal operating conditions over a range of preselected moisture contents (45-75%) and C/N ratios (13.9-19.6). The results indicate that the optimal moisture content for co-composting of food waste and green waste is 60%, and the substrate at a C/N ratio of 19.6 can be decomposed effectively to reduce 33% of total volatile solids (TVS) in 12 days. The TVSmore » reduction can be modeled by using a second-order equation with a good fit. In addition, the compost passes the standard germination index of white radish seed indicating that it can be used as soil amendment.« less
Biogas potential from anaerobic co-digestion of faecal sludge with food waste and garden waste
NASA Astrophysics Data System (ADS)
Afifah, Ukhtiy; Priadi, Cindy Rianti
2017-03-01
The limited faecal sludge management can be optimized by converting the sludge into biogas. This study purposed to optimize the biogas potential of faecal sludge with food waste and garden waste. The system using Anaerobic Co-digestion on the variation 25% and 50% concentration of faecal sludge based on Volatile Solids (VS). Inoculum used was cow's rumen. The study was operated using lab-scale batch reactor 51 L for 42 days. Biogas produced at 25% concentration of faecal sludge is 0,30 m3CH4/kg with 71,93% VS and 72,42% COD destruction. Meanwhile, at 50% concentration of faecal sludge produce 0,56 m3CH4/kg VS biogas with 92,43% VS and 87,55% COD destruction. This study concludes that biogas potential of 50% concentration greater than 25% concentration of faecal sludge.
Parallel RNA extraction using magnetic beads and a droplet array.
Shi, Xu; Chen, Chun-Hong; Gao, Weimin; Chao, Shih-Hui; Meldrum, Deirdre R
2015-02-21
Nucleic acid extraction is a necessary step for most genomic/transcriptomic analyses, but it often requires complicated mechanisms to be integrated into a lab-on-a-chip device. Here, we present a simple, effective configuration for rapidly obtaining purified RNA from low concentration cell medium. This Total RNA Extraction Droplet Array (TREDA) utilizes an array of surface-adhering droplets to facilitate the transportation of magnetic purification beads seamlessly through individual buffer solutions without solid structures. The fabrication of TREDA chips is rapid and does not require a microfabrication facility or expertise. The process takes less than 5 minutes. When purifying mRNA from bulk marine diatom samples, its repeatability and extraction efficiency are comparable to conventional tube-based operations. We demonstrate that TREDA can extract the total mRNA of about 10 marine diatom cells, indicating that the sensitivity of TREDA approaches single-digit cell numbers.
Parallel RNA extraction using magnetic beads and a droplet array
Shi, Xu; Chen, Chun-Hong; Gao, Weimin; Meldrum, Deirdre R.
2015-01-01
Nucleic acid extraction is a necessary step for most genomic/transcriptomic analyses, but it often requires complicated mechanisms to be integrated into a lab-on-a-chip device. Here, we present a simple, effective configuration for rapidly obtaining purified RNA from low concentration cell medium. This Total RNA Extraction Droplet Array (TREDA) utilizes an array of surface-adhering droplets to facilitate the transportation of magnetic purification beads seamlessly through individual buffer solutions without solid structures. The fabrication of TREDA chips is rapid and does not require a microfabrication facility or expertise. The process takes less than 5 minutes. When purifying mRNA from bulk marine diatom samples, its repeatability and extraction efficiency are comparable to conventional tube-based operations. We demonstrate that TREDA can extract the total mRNA of about 10 marine diatom cells, indicating that the sensitivity of TREDA approaches single-digit cell numbers. PMID:25519439
Optical coherence of 166Er:7LiYF4 crystal below 1 K
NASA Astrophysics Data System (ADS)
Kukharchyk, N.; Sholokhov, D.; Morozov, O.; Korableva, S. L.; Kalachev, A. A.; Bushev, P. A.
2018-02-01
We explore optical coherence and spin dynamics of an isotopically purified 166Er:7LiYF4 crystal below 1 K and at weak magnetic fields < 0.3T. Crystals were grown in our lab and demonstrate narrow inhomogeneous optical broadening down to 16 MHz. Solid-state atomic ensembles with such narrow linewidths are very attractive for implementing of off-resonant Raman quantum memory and for the interfacing of superconducting quantum circuits and telecom C-band optical photons. Both applications require a low magnetic field of ∼10 mT. However, at conventional experimental temperatures T > 1.5 K, optical coherence of Er:LYF crystal attains ≃ 10 μ {{s}} time scale only at strong magnetic fields above 1.5 T. In the present work, we demonstrate that the deep freezing of Er:LYF crystal below 1 K results in the increase of optical coherence time to ≃ 100 μ {{s}} at weak fields.
Potential Water Reuse for High Strength Fruit and Vegetable Processor Wastewater with an MBR.
Moore, Adam W; Zytner, Richard G; Chang, Sheng
High strength food processing wastewater from two processing plants was studied to determine the effectiveness of an aerobic membrane bioreactor (MBR) to reduce BOD, TSS and nutrients below municipal sewer discharge limits. The MBR comprised a 20 L lab-scale reactor combined with a flat sheet, ultrafiltration membrane module. The parameters studied included the operational flux, solids and hydraulic retention times and recirculation ratio with regards to nitrification/denitrification. The MBR system provided excellent removal efficiency at 97% COD, 99% BOD, 99.9% TSS, 90% TKN, and 60% TP for both processing plants, which eliminated the surcharges, allowing the firms to stay competitive. Effluent reuse tests showed that activated carbon proved effective in removing color from the MBR permeate, while UV treatment was able to achieve a 5 log reduction in bacteriophage. Overall, these treatment successes show the potential for water reuse in the agrifood sector.
Kaigala, Govind V; Hoang, Viet N; Backhouse, Christopher J
2008-07-01
Microvalves are key in realizing portable miniaturized diagnostic platforms. We present a scalable microvalve that integrates well with standard lab on a chip (LOC) implementations, yet which requires essentially no external infrastructure for its operation. This electrically controlled, phase-change microvalve is used to integrate genetic amplification and analysis via capillary electrophoresis--the basis of many diagnostics. The microvalve is actuated using a polymer (polyethylene glycol, PEG) that exhibits a large volumetric change between its solid and liquid phases. Both the phase change of the PEG and the genetic amplification via polymerase chain reaction (PCR) are thermally controlled using thin film resistive elements that are patterned using standard microfabrication methods. By contrast with many other valve technologies, these microvalves and their control interface scale down in size readily. The novelty here lies in the use of fully integrated microvalves that require only electrical connections to realize a portable and inexpensive genetic analysis platform.
STS-114: Crew Training Clip from JSC
NASA Technical Reports Server (NTRS)
2003-01-01
STS-114 Discovery crew is shown in various training exercises at Johnson Space Center. The crew consists of Eileen Collins, Commander; James Kelley, Pilot; Charles Camarda, Mission Specialist; Wendy Lawrence, Mission Specialist; Soichi Noguchi, Mission Specialist; Steve Robinson, Mission Specialist; and Andy Thomas, Mission Specialist. The exercises include: 1) EVA training in the VR lab; 2) Neutral Buoyancy Laboratory (NBL) EVA Training; 3) Walk to Motion Base Simulator; 4) EVA Preparations in ISS Airlock; and 7) Emergency Egress from Crew Compartment Trainer (CCT). A crew photo session is also presented. Footage of The Space Shuttle Atlantis inside the Kennedy Space Center Vehicle Assembly Building (VAB) after its demating from the Solid Rocket Booster and External Tank is shown. The video ends with techniques for inspecting and repairing Thermal Protection System tiles, a video of external tank production at the Michoud Assembly Facility (MAF) and redesign of the foam from the bipod ramp at Michoud Assembly Facility (MAF).