Spatially Resolved Dissolution and Speciation Changes of ZnO Nanorods during Short-Term in Situ Incubation in a Simulated Wastewater Environment

In situ FT-IR microspectroscopy has allowed spatially resolved interrogation of different parts of brain tissue. In previous work the spectrrscopic features of normal barin tissue were characterized. The white matter, gray matter and basal ganglia were mapped from appropriate peak area measurements from spectra obtained in a grid pattern. Bands prevalent in white matter were mostly associated with the lipid. These included 2927 and 1469 cm-1 due to CH2 as well as carbonyl at 1740 cm-1. Also 1235 and 1085 cm-1 due to phospholipid and galactocerebroside, respectively (Figs 1and2). Localized chemical changes in the white matter as a result of white matter diseases have been studied. This involved the documentation of localized chemical evidence of demyelination in shiverer mice in which the spectra of white matter lacked the marked contrast between it and gray matter exhibited in the white matter of normal mice (Fig. 3).The twitcher mouse, a model of Krabbe’s desease, was also studied. The purpose in this case was to look for a localized build-up of psychosine in the white matter caused by deficiencies in the enzyme responsible for its breakdown under normal conditions.

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Spatially Resolved Experimental Modal Analysis on High-Speed Composite Rotors Using a Non-Contact, Non-Rotating Sensor

Sensors ◽

10.3390/s21144705 ◽

2021 ◽

Vol 21 (14) ◽

pp. 4705

Author(s):

Julian Lich ◽

Tino Wollmann ◽

Angelos Filippatos ◽

Maik Gude ◽

Juergen Czarske ◽

...

Keyword(s):

High Speed ◽

Natural Frequencies ◽

Mode Shapes ◽

Fiber Reinforced ◽

Structural Dynamic ◽

Spatially Resolved ◽

Glass Fiber Reinforced ◽

Vibration Responses ◽

And Performance

Due to their lightweight properties, fiber-reinforced composites are well suited for large and fast rotating structures, such as fan blades in turbomachines. To investigate rotor safety and performance, in situ measurements of the structural dynamic behaviour must be performed during rotating conditions. An approach to measuring spatially resolved vibration responses of a rotating structure with a non-contact, non-rotating sensor is investigated here. The resulting spectra can be assigned to specific locations on the structure and have similar properties to the spectra measured with co-rotating sensors, such as strain gauges. The sampling frequency is increased by performing consecutive measurements with a constant excitation function and varying time delays. The method allows for a paradigm shift to unambiguous identification of natural frequencies and mode shapes with arbitrary rotor shapes and excitation functions without the need for co-rotating sensors. Deflection measurements on a glass fiber-reinforced polymer disk were performed with a diffraction grating-based sensor system at 40 measurement points with an uncertainty below 15 μrad and a commercial triangulation sensor at 200 measurement points at surface speeds up to 300 m/s. A rotation-induced increase of two natural frequencies was measured, and their mode shapes were derived at the corresponding rotational speeds. A strain gauge was used for validation.

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Airborne determination of the temporo-spatial distribution of benzene, toluene, nitrogen oxides and ozone in the boundary layer across Greater London, UK

Atmospheric Chemistry and Physics ◽

10.5194/acp-15-5083-2015 ◽

2015 ◽

Vol 15 (9) ◽

pp. 5083-5097 ◽

Cited By ~ 16

Author(s):

M. D. Shaw ◽

J. D. Lee ◽

B. Davison ◽

A. Vaughan ◽

R. M. Purvis ◽

...

Keyword(s):

Boundary Layer ◽

Nitrogen Oxides ◽

Linear Regression Analysis ◽

Proton Transfer Reaction ◽

Mixing Ratios ◽

Spatially Resolved ◽

Dual Channel ◽

Benzene Toluene

Abstract. Highly spatially resolved mixing ratios of benzene and toluene, nitrogen oxides (NOx) and ozone (O3) were measured in the atmospheric boundary layer above Greater London during the period 24 June to 9 July 2013 using a Dornier 228 aircraft. Toluene and benzene were determined in situ using a proton transfer reaction mass spectrometer (PTR-MS), NOx by dual-channel NOx chemiluminescence and O3 mixing ratios by UV absorption. Average mixing ratios observed over inner London at 360 ± 10 m a.g.l. were 0.20 ± 0.05, 0.28 ± 0.07, 13.2 ± 8.6, 21.0 ± 7.3 and 34.3 ± 15.2 ppbv for benzene, toluene, NO, NO2 and NOx respectively. Linear regression analysis between NO2, benzene and toluene mixing ratios yields a strong covariance, indicating that these compounds predominantly share the same or co-located sources within the city. Average mixing ratios measured at 360 ± 10 m a.g.l. over outer London were always lower than over inner London. Where traffic densities were highest, the toluene / benzene (T / B) concentration ratios were highest (average of 1.8 ± 0.5 ppbv ppbv-1), indicative of strong local sources. Daytime maxima in NOx, benzene and toluene mixing ratios were observed in the morning (~ 40 ppbv NOx, ~ 350 pptv toluene and ~ 200 pptv benzene) and in the mid-afternoon for ozone (~ 40 ppbv O3), all at 360 ± 10 m a.g.l.

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Long Short-Term Memory Neural Network (LSTM-NN) for Aquifer Level Time Series Forecasting Using in-Situ Piezometric Observations

Journal of Hydrology ◽

10.1016/j.jhydrol.2021.126800 ◽

2021 ◽

pp. 126800

Author(s):

Ryan Solgi ◽

Hugo A. Loáiciga ◽

Mark Kram

Keyword(s):

Neural Network ◽

Time Series ◽

Short Term Memory ◽

Time Series Forecasting ◽

Short Term ◽

Term Memory ◽

Long Short Term Memory

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In Situ Biaxial Mechanical Testing at the Neutron Time-of-Flight Diffractometer POLDI

Materials Science Forum ◽

10.4028/www.scientific.net/msf.768-769.60 ◽

2013 ◽

Vol 768-769 ◽

pp. 60-65 ◽

Cited By ~ 11

Author(s):

Julia Repper ◽

Markus Niffenegger ◽

Steven van Petegem ◽

Werner Wagner ◽

Helena van Swygenhoven

Keyword(s):

Steel Sample ◽

Mechanical Tests ◽

Image Correlation ◽

Uniaxial Deformation ◽

Spatially Resolved ◽

Neutron Diffractometer ◽

Neutron Time ◽

Strain Paths ◽

Biaxial Mechanical Testing

Complex strain paths are often applied to materials during production processes. This paper shows the first successful in-situ biaxial mechanical tests during neutron diffraction performed on a cruciform steel sample and reports on the differences compared to uniaxial deformation. Digital image correlation is demonstrated to be an appropriate tool to monitor spatially resolved the macroscopic straining. The new, modular biaxial machine that will be installed at the neutron diffractometer POLDI is presented.

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In situ studies on alginic acid synthesis and other aspects of the metabolism of Laminaria digitata

Canadian Journal of Botany ◽

10.1139/b72-023 ◽

1972 ◽

Vol 50 (1) ◽

pp. 177-184 ◽

Cited By ~ 10

Author(s):

Johan A. Hellebust ◽

Arne Haug

Keyword(s):

Amino Acids ◽

Time Course ◽

Alginic Acid ◽

Acid Synthesis ◽

Short Term ◽

Fresh Weight Basis ◽

Mannuronic Acid ◽

Guluronic Acid ◽

Rate Of Photosynthesis

Amino acids, particularly alanine and aspartate, become more strongly labeled than mannitol in short-term 14C-photoassimilation experiments. The amino acids are the most likely sources of carbon for alginic acid synthesis and respiration in the dark, in contrast to mannitol, which appears to be relatively unavailable. Temperature is very important in determining the rate of loss of recent photoassimilate in L. digitata. The rate of photosynthesis, on a fresh weight basis, is much higher for blades than for stipes.The time course for incorporation of photoassimilated carbon into alginate differs for the stipe and blade both in light and dark periods. Very little 14C enters alginate in blades in the dark, while alginate in stipes acquires considerable amounts of activity during dark periods. Alginate in both blade and stipe acquires 14C predominantly in mannuronic acid residues of their alginate during short-term photoassimilation periods, while guluronic acid residues become relatively more rapidly labeled during dark periods.

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0638 Effects of cow and bag type on the undigested neutral detergent fiber after two hundred forty hours in situ incubation

Journal of Animal Science ◽

10.2527/jam2016-0638 ◽

2016 ◽

Vol 94 (suppl_5) ◽

pp. 304-305

Author(s):

H. Yang ◽

Y. Yan ◽

D. J. Undersander ◽

D. K. Combs

Keyword(s):

Neutral Detergent Fiber ◽

In Situ Incubation

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Structural basis of muscle O2 diffusing capacity: evidence from muscle function in situ

Journal of Applied Physiology ◽

10.1152/jappl.2000.88.2.560 ◽

2000 ◽

Vol 88 (2) ◽

pp. 560-566 ◽

Cited By ~ 68

Author(s):

Russell T. Hepple ◽

Michael C. Hogan ◽

Creed Stary ◽

Donald E. Bebout ◽

Odile Mathieu-Costello ◽

...

Keyword(s):

Gastrocnemius Muscle ◽

Capillary Density ◽

Structural Basis ◽

Diffusing Capacity ◽

Diffusion Distance ◽

Short Term ◽

Cross Sectional ◽

Intact Organism ◽

Minimal Reduction

Although evidence for muscle O2 diffusion limitation of maximal O2 uptake has been found in the intact organism and isolated muscle, its relationship to diffusion distance has not been examined. Thus we studied six sets of three purpose-bred littermate dogs (aged 10–12 mo), with 1 dog per litter allocated to each of three groups: control (C), exercise trained for 8 wk (T), or left leg immobilized for 3 wk (I). The left gastrocnemius muscle from each animal was surgically isolated, pump-perfused, and electrically stimulated to peak O2 uptake at three randomly applied levels of arterial oxygenation [normoxia, arterial[Formula: see text]([Formula: see text]) 77 ± 2 (SE) Torr; moderate hypoxia, [Formula: see text]: 33 ± 1 Torr; and severe hypoxia, [Formula: see text]: 22 ± 1 Torr]. O2 delivery (ml ⋅ min−1 ⋅ 100 g− 1) was kept constant among groups for each level of oxygenation, with O2 delivery decreasing with decreasing [Formula: see text]. O2extraction (%) was lower in I than T or C for each condition, but calculated muscle O2 diffusing capacity (Dm[Formula: see text]) per 100 grams of muscle was not different among groups. After the experiment, the muscle was perfusion fixed in situ, and a sample from the midbelly was processed for microscopy. Immobilized muscle showed a 45% reduction of muscle fiber cross-sectional area ( P < 0.05), and a resulting 59% increase in capillary density ( P < 0.05) but minimal reduction in capillary-to-fiber ratio (not significant). In contrast, capillarity was not significantly different in T vs. C muscle. The results show that a dramatically increased capillary density (and reduced diffusion distance) after short-term immobilization does not improve Dm[Formula: see text] in heavily working skeletal muscle.

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Temporal Variation of Chlorophyll-a Concentrations in Highly Dynamic Waters from Unattended Sensors and Remote Sensing Observations

Sensors ◽

10.3390/s18082699 ◽

2018 ◽

Vol 18 (8) ◽

pp. 2699 ◽

Cited By ~ 2

Author(s):

Jian Li ◽

Liqiao Tian ◽

Qingjun Song ◽

Zhaohua Sun ◽

Hongjing Yu ◽

...

Keyword(s):

Remote Sensing ◽

Water Quality ◽

Chlorophyll Fluorescence ◽

Chlorophyll A ◽

Temporal Variations ◽

Lake Area ◽

Short Term ◽

Chl A ◽

Spatio Temporal

Monitoring of water quality changes in highly dynamic inland lakes is frequently impeded by insufficient spatial and temporal coverage, for both field surveys and remote sensing methods. To track short-term variations of chlorophyll fluorescence and chlorophyll-a concentrations in Poyang Lake, the largest freshwater lake in China, high-frequency, in-situ, measurements were collected from two fixed stations. The K-mean clustering method was also applied to identify clusters with similar spatio-temporal variations, using remote sensing Chl-a data products from the MERIS satellite, taken from 2003 to 2012. Four lake area classes were obtained with distinct spatio-temporal patterns, two of which were selected for in situ measurement. Distinct daily periodic variations were observed, with peaks at approximately 3:00 PM and troughs at night or early morning. Short-term variations of chlorophyll fluorescence and Chl-a levels were revealed, with a maximum intra-diurnal ratio of 5.1 and inter-diurnal ratio of 7.4, respectively. Using geostatistical analysis, the temporal range of chlorophyll fluorescence and corresponding Chl-a variations was determined to be 9.6 h, which indicates that there is a temporal discrepancy between Chl-a variations and the sampling frequency of current satellite missions. An analysis of the optimal sampling strategies demonstrated that the influence of the sampling time on the mean Chl-a concentrations observed was higher than 25%, and the uncertainty of any single Terra/MODIS or Aqua/MODIS observation was approximately 15%. Therefore, sampling twice a day is essential to resolve Chl-a variations with a bias level of 10% or less. The results highlight short-term variations of critical water quality parameters in freshwater, and they help identify specific design requirements for geostationary earth observation missions, so that they can better address the challenges of monitoring complex coastal and inland environments around the world.

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