TRACERS DERIVED IN SITU REPLICATE AND MIX BETTER THAN FALLOUT TRACERS INCORPORATED INTO GRAIN COATINGS

Figure 1 shows the design of a specimen stage used for the in situ observation of phase transformations in the temperature range between ambient and −160°C. The design has the following features a high degree of specimen stability during tilting linear tilt actuation about two orthogonal axes for accurate control of tilt angle read-out high angle tilt range for stereo work and habit plane determination simple, robust construction temperature control of better than ±0.5°C minimum thermal drift and transmission of vibration from the cooling system.

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STUDIES ON THE AROMATISATION OF NEUTRAL STEROIDS IN PREGNANT WOMEN

Acta Endocrinologica ◽

10.1530/acta.0.0450535 ◽

1964 ◽

Vol 45 (4) ◽

pp. 535-559 ◽

Cited By ~ 88

Author(s):

E. Bolté ◽

S. Mancuso ◽

G. Eriksson ◽

N. Wiqvist ◽

E. Diczfalusy

Keyword(s):

Pregnant Women ◽

Comparative Studies ◽

Chorionic Gonadotrophin ◽

Human Chorionic Gonadotrophin ◽

Radioactive Material ◽

Placental Barrier ◽

Therapeutic Abortion ◽

Limited Ability ◽

Better Than

ABSTRACT In 15 cases of therapeutic abortion by laparotomy the placenta was disconnected from the foetus and perfused in situ with tracer amounts of radioactive dehydroepiandrosterone (DHA), dehydroepiandrosterone sulphate (DHAS), androst-4-ene-3,17-dione (A), testosterone (T) and 17β-oestradiol (OE2). Analysis of the placentas, perfusates and urine samples revealed an extensive aromatisation of DHA, A and T; more than 70% of the radioactive material recovered was phenolic, and at least 80 % of this phenolic material was identified as oestrone (OE1), 17β-oestradiol (OE2) and oestriol (OE3), the latter being detected only in the urine. Comparative studies indicated that A and T were aromatised somewhat better than DHA and that all three unconjugated steroids were aromatised to a much greater extent than DHAS. Radioactive OE1 and OE2 were isolated and identified in the placentas and perfusates, but no OE3, epimeric oestriols, or ring D ketols could be detected in these sources, not even when human chorionic gonadotrophin (HCG) was added to the blood prior to perfusion. Lack of placental 16-hydroxylation was also apparent when OE2 was perfused. Regardless of the precursor perfused, there was three times more OE2 than OE1 in the placenta and three times more OE1 than OE2 in the perfusate. This was also the case following perfusion with OE2. The results are interpreted as suggesting the existence in the pregnant human of a placental »barrier« limiting the passage of circulating androgen. The barrier consists of a) limited ability to transfer directly DHAS and b) an enzymic mechanism resulting in the rapid and extensive aromatisation of the important androgens DHA, A and T.

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Performance of the SoLid reactor neutrino detector

EPJ Web of Conferences ◽

10.1051/epjconf/201921908003 ◽

2019 ◽

Vol 219 ◽

pp. 08003

Author(s):

Maja Verstraeten

Keyword(s):

Quality Control ◽

Energy Resolution ◽

Neutrino Detector ◽

Channel Response ◽

In Situ Calibration ◽

Reactor Neutrino ◽

Li Isotope ◽

Better Than

The SoLid Collaboration is currently operating a 1.6 ton neutrino detector near the Belgian BR2 reactor. Its main goal is the observation of the oscillation of electron antineutrinos to previously undetected flavour states. The highly segmented SoLid detector employs a compound scintillation technology based on PVT scintillator in combination with LiF-ZnS(Ag) screens containing the 6Li isotope. The experiment has demonstrated a channel-to-channel response that can be controlled to the level of a few percent, an energy resolution of better than 14% at 1 MeV, and a determination of the interaction vertex with a precision of 5 cm. This contribution highlights the major outcomes of the R&D program, the quality control during component manufacture and integration, the current performance and stability of the full-scale system, as well as the in-situ calibration of the detector with various radioactive sources.

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Test Methods for Mechanical Properties of Structural Adhesives

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.814 ◽

2010 ◽

Vol 97-101 ◽

pp. 814-817 ◽

Cited By ~ 1

Author(s):

Jun Deng

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Shear Strength ◽

Elastic Modulus ◽

Butt Joint ◽

Test Methods ◽

Joint Specimen ◽

Lap Shear ◽

Better Than

One of the greatest drawbacks to predicting the behaviour of bonded joints has been the lack of reliable data on the mechanical properties of adhesives. In this study, methods for determining mechanical properties of structural adhesive were discussed. The Young’s modulus, Poisson’s ratio and tensile strength of the adhesive were tested by dogbone specimens (bulk form) and butt joint specimens (in situ form). The shear modulus and shear strength were test by V-notched specimens (bulk form) and thick adherend lap-shear (TALS) joint specimens (in situ form). The test results show that the elastic modulus provided by the manufacturer is too low, the dogbone specimen is better than the butt joint specimen to test the tensile strength and elastic modulus and the TALS joint specimen is better than the V-notched specimen to test the shear strength.

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Global downscaling of remotely sensed soil moisture using neural networks

Hydrology and Earth System Sciences ◽

10.5194/hess-22-5341-2018 ◽

2018 ◽

Vol 22 (10) ◽

pp. 5341-5356 ◽

Cited By ~ 10

Author(s):

Seyed Hamed Alemohammad ◽

Jana Kolassa ◽

Catherine Prigent ◽

Filipe Aires ◽

Pierre Gentine

Keyword(s):

Soil Moisture ◽

Spatial Resolution ◽

Land Surface ◽

Vegetation Index ◽

Spatial Scales ◽

Ancillary Data ◽

Repeat Time ◽

Spatiotemporal Scales ◽

Better Than

Abstract. Characterizing soil moisture at spatiotemporal scales relevant to land surface processes (i.e., of the order of 1 km) is necessary in order to quantify its role in regional feedbacks between the land surface and the atmospheric boundary layer. Moreover, several applications such as agricultural management can benefit from soil moisture information at fine spatial scales. Soil moisture estimates from current satellite missions have a reasonably good temporal revisit over the globe (2–3-day repeat time); however, their finest spatial resolution is 9 km. NASA's Soil Moisture Active Passive (SMAP) satellite has estimated soil moisture at two different spatial scales of 36 and 9 km since April 2015. In this study, we develop a neural-network-based downscaling algorithm using SMAP observations and disaggregate soil moisture to 2.25 km spatial resolution. Our approach uses the mean monthly Normalized Differenced Vegetation Index (NDVI) as ancillary data to quantify the subpixel heterogeneity of soil moisture. Evaluation of the downscaled soil moisture estimates against in situ observations shows that their accuracy is better than or equal to the SMAP 9 km soil moisture estimates.

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In-situ determination of astro-comb calibrator lines to better than 10 cm s^-1

Optics Express ◽

10.1364/oe.18.013239 ◽

2010 ◽

Vol 18 (12) ◽

pp. 13239 ◽

Cited By ~ 30

Author(s):

Chih-Hao Li ◽

Alexander G. Glenday ◽

Andrew J. Benedick ◽

Guoqing Chang ◽

Li-Jin Chen ◽

...

Keyword(s):

Better Than

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Efficient and Semiefficient Vulcanization Systems Employing 2-(Morpholinodithio)-Benzothiazole Generated in Situ

Rubber Chemistry and Technology ◽

10.5254/1.3535137 ◽

1977 ◽

Vol 50 (1) ◽

pp. 90-98

Author(s):

J. P. Lawrence

Keyword(s):

Heat Resistance ◽

Experimental System ◽

Heat Resistant ◽

Molar Basis ◽

Direct Replacement ◽

Better Than

Abstract The MBTS-N-(morpholinothio)phthalimide vulcanization system has been found to be effective in producing heat resistant semi-EV and EV cures in a variety of representative rubbers. When used as a direct replacement on a molar basis for 2-(morpholinodithio)benzothiazole (MDB), improvements in processing safety were found in all cases studied. In this respect it is most effective in NR, SBR, and NBR. The experimental system also generally gave slower-curing stocks. The heat resistance of the experimental stocks was found to be equal to or better than that of the MDB control stocks. Substantial improvements in heat resistance for both SBR and IIR unexpectedly resulted from the use of the MBTS—imide system. This result suggests that the nature of the crosslinks formed by the two vulcanization systems are to some extent different in these two elastomers. This, in turn, may reflect upon the mechanisms of crosslink formation.

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New Instrumentation in Argonne's Hvem-Tandem Facility: Expanded Capability for in Situ Ion Beam Studies+

MRS Proceedings ◽

10.1557/proc-396-641 ◽

1995 ◽

Vol 396 ◽

Cited By ~ 33

Author(s):

Charles W. Allen ◽

Loren L. Funk ◽

Edward A. Ryan

Keyword(s):

Scientific Community ◽

State Of The Art ◽

Ion Irradiation ◽

Ion Beam ◽

Voltage Electron ◽

User Facility ◽

Order Of Magnitude ◽

New Instrumentation ◽

Better Than

AbstractDuring 1995, a state-of-the-art intermediate voltage electron microscope (IVEM) has been installed in the HVEM-Tandem Facility with in situ ion irradiation capabilities similar to those of the HVEM. A 300 kV Hitachi H-9000NAR has been interfaced to the two ion accelerators of the Facility, with a spatial resolution for imaging which is nearly an order of magnitude better than that for the 1.2 MV HVEM which dates from the early 1970s. The HVEM remains heavily utilized for electron- and ion irradiation-related materials studies, nevertheless, especially those for which less demanding microscopy is adequate. The capabilities and limitations of this IVEM and HVEM are compared. Both the HVEM and IVEM are part of the DOE funded User Facility and therefore are available to the scientific community for materials studies, free of charge for non-proprietary research.

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Assessment of Temperature and Specific Humidity Inversions and Their Relationships in Three Global Reanalysis Products over the Arctic Ocean

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-20-0079.1 ◽

2021 ◽

Vol 60 (4) ◽

pp. 493-511

Author(s):

Liang Chang ◽

Shiqiang Wen ◽

Guoping Gao ◽

Zhen Han ◽

Guiping Feng ◽

...

Keyword(s):

Arctic Ocean ◽

Specific Humidity ◽

The Arctic ◽

Weather Forecasts ◽

The Arctic Ocean ◽

Temperature Inversions ◽

Global Reanalysis ◽

Less Common Multiple ◽

Better Than

AbstractCharacteristics of temperature inversions (TIs) and specific humidity inversions (SHIs) and their relationships in three of the latest global reanalyses—the European Centre for Medium-Range Weather Forecasts Interim Reanalysis (ERA-I), the Japanese 55-year Reanalysis (JRA-55), and the ERA5—are assessed against in situ radiosonde (RS) measurements from two expeditions over the Arctic Ocean. All reanalyses tend to detect many fewer TI and SHI occurrences, together with much less common multiple TIs and SHIs per profile than are seen in the RS data in summer 2008, winter 2015, and spring 2015. The reanalyses generally depict well the relationships among TI characteristics seen in RS data, except for the TIs below 400 m in summer, as well as above 1000 m in summer and winter. The depth is simulated worst by the reanalyses among the SHI characteristics, which may result from its sensitivity to the uncertainties in specific humidity in the reanalyses. The strongest TI per profile in RS data exhibits more robust dependency on surface conditions than the strongest SHI per profile, and the former is better presented by the reanalyses than the latter. Furthermore, all reanalyses have difficulties simulating the relationships between TIs and SHIs, together with the correlations between the simultaneous inversions. The accuracy and vertical resolution in the reanalyses are both important to properly capture occurrence and characteristics of the Arctic inversions. In general, ERA5 performs better than ERA-I and JRA-55 in depicting the relationships among the TIs. However, the representation of SHIs is more challenging than TIs in all reanalyses over the Arctic Ocean.

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In-Situ LED-Based Observation of Snow Surface and Depth Transects

Sensors ◽

10.3390/s20082292 ◽

2020 ◽

Vol 20 (8) ◽

pp. 2292

Author(s):

Celeste Barnes ◽

Chris Hopkinson ◽

Thomas Porter ◽

Zhouxin Xi

Keyword(s):

Snow Depth ◽

Surface Albedo ◽

Surface Condition ◽

Field Of View ◽

Snow Surface ◽

Depth Measurement ◽

Individual Distance ◽

Strong Linear Relationship ◽

Better Than

As part of a new snowpack monitoring framework, this study evaluated the feasibility of using an LED LIDAR (Leddar) time of flight sensor for snowpack depth measurement. The Leddar sensor has two additional features over simple sonic ranging sensors: (i) the return signal is divided into 16 segments across a 48° field of view, each recording individual distance-to-target (DTT) measurements; (ii) an index of reflectance or intensity signal is recorded for each segment. These two features provide information describing snowpack morphology and surface condition. The accuracy of Leddar sensor DTT measurements for snow depth monitoring was found to be < 20 mm, which was better than the 50 mm quoted by the manufacturer, and the precision was < 5 mm. Leddar and independent sonic ranger snow depth measurement showed strong linear agreement (r2 = 0.98). There was also a strong linear relationship (r2 = 0.98) between Leddar and manual field snow depth measurements. The intensity signal response was found to correlate with snow surface albedo and inversely with air temperature (r = 0.77 and −0.77, respectively).

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