Search results for " magnitude"
showing 10 items of 407 documents
Highly efficient isotope separation and ion implantation of 163Ho for the ECHo project
2019
Abstract The effective electron neutrino mass measurement in the framework of the ECHo experiment requires radiochemically pure 163 Ho, which is ion implanted into detector absorbers. To meet the project specifications in efficiency and purity, the entire process chain of ionization, isotope separation , and implantation of 163Ho was optimized. A new two-step resonant laser ionization scheme was established at the 30 kV magnetic mass separator RISIKO. For ionization and separation, an average efficiency of 69 ( 5 ) stat(4)sys% was achieved using intra-cavity frequency doubled Ti:sapphire lasers. The implantation of undesired 166 m Ho, which is present in trace amounts in the initial 163Ho…
A Hard X-Ray View of Scorpius X-1 with INTEGRAL : Nonthermal Emission?
2006
We present here simultaneous INTEGRAL/RXTE observations of Sco X-1, and in particular a study of the hard X-ray emission of the source and its correlation with the position in the Z-track of the X-ray color-color diagram. We find that the hard X-ray (above about 30 keV) emission of Sco X-1 is dominated by a power-law component with a photon index of ~3. The flux in the power-law component slightly decreases when the source moves in the color-color diagram in the sense of increasing inferred mass accretion rate from the horizontal branch to the normal branch/flaring branch vertex. It becomes not significantly detectable in the flaring branch, where its flux has decreased by about an order of…
A comprehensive characterization of ice nucleation by three different types of cellulose particles immersed in water: lessons learned and future rese…
2018
We present the laboratory results of immersion freezing efficiencies of cellulose particles at supercooled temperature (T) conditions. Three types of chemically homogeneous cellulose samples are used as surrogates that represent supermicron and submicron ice nucleating plant structural polymers. These samples include micro-crystalline cellulose (MCC), fibrous cellulose (FC) and nano-crystalline cellulose (NCC). Our experimental data show that particles resembling the MCC lab particle occur also in the atmosphere. Our immersion freezing dataset includes data from various ice nucleation measurement techniques available at seventeen different institutions, including nine dry dispersion and ele…
Aqueous coefficient calculations for chemicals and drugs
1999
Aqueous functional group activity coefficients (AQUAFAC) is a group‐contribution method for estimating the aqueous coefficients. We have written a program for the calculation of these coefficients. The solubility S w of alkanes shows variation of 8 orders of magnitude. The comparison with experiment shows that AQUAFAC gives good S w estimations. For 4'‐substituted acetanilides, I‐, Br‐, nitro‐, Cl‐, F‐ and methoxy‐substituents decrease S w, while formyl‐ and amino‐substituents increase S w. For acetaminophen esters, S w decreases from the acetate to the decanoate. The S w of 29 barbiturates shows typical errors of 0.4 log S w units. For the cyclo‐alkane‐l’,5‐spirobarbituric acids, S w decre…
Sorption Kinetics of Xenon on MFI-Type Zeolite Molecular Sieves
1990
Kinetic uptake data for xenon adsorbed onto large and uniform silicalite-I crystals are presented over a temperature range of 121 K to 296 K. — Adsorption isotherms and corrected diffusion coefficients derived from the uptake curves are given. The heat of adsorption and activation energy of diffusion were estimated from the plots of reciprocal temperature against the logarithm of equilibrium pressure and corrected diffusion coefficients, respectively. — While the corrected diffusion coefficient is independent of coverage for the higher temperatures, it decreases significantly at the lower temperatures investigated (<170 K) when the limiting adsorption capacity has been reached. — Comparing …
On-Capillary Surface-Enhanced Raman Spectroscopy: Determination of Glutathione in Whole Blood Microsamples.
2018
Oxidative stress monitoring in the neonatal period supports early outcome prediction and treatment. Glutathione (GSH) is the most abundant antioxidant in most cells and tissues, including whole blood, and its usefulness as a biomarker has been known for decades. To date, the available methods for GSH determination require laborious sample processing and the use of sophisticated laboratory equipment. To the best of our knowledge, no tools suitable for point-of-care (POC) sensing have been reported. Surface-enhanced Raman spectroscopy (SERS), performed in a microvolume capillary measurement cell, is proposed in this study as a robust approach for the quantification of GSH in human whole blood…
Internal exposure of the general population to DEHP and other phthalates--determination of secondary and primary phthalate monoester metabolites in u…
2003
A number of phthalates and their metabolites are suspected of having teratogenic and endocrine disrupting effects. Especially the developmental and reproductive effects of di(2-ethylhexyl)phthalate (DEHP) are under scrutiny. In this study we determined the concentrations of the secondary, chain oxidized monoester metabolites of DEHP, mono(2-ethyl-5-hydroxyhexyl)phthalate (5OH-MEHP) and mono(2-ethyl-5-oxo-hexyl)phthalate (5oxo-MEHP) in urine samples from the general population. The utilization of the secondary metabolites minimized any risk of contamination by the ubiquitously present phthalate parent compounds. Included in the method were also the simple monoester metabolites of DEHP, dioct…
Perceiving numbers alters time perception.
2008
The representation of time, space and numbers are strictly linked in the primate's cognitive system. Here we show that merely looking at number symbols biases a temporal judgment on their duration depending upon the number's magnitude. In a first experiment, a group of healthy subjects was submitted to a time estimation task, requiring to judge whether the duration of a test stimulus was longer or shorter than that of a previous reference fixed stimulus (digit 5; duration 300 ms). Test stimuli were the digits 1, 5 and 9 ranging between 250 and 350 ms. The main results showed that temporal perception was biased according to the magnitude expressed by the digit: low digits (i.e. 1) leading to…
Measurement and correction of atmospheric effects in O<inf>2</inf>-B and O<inf>2</inf>-A absorption bands in the context of s…
2014
Under sun-light illumination, the shape of the atmospheric oxygen bands (O 2 -B, 687 nm and O 2 -A, 760 nm) of the vegetation radiance is modified by chlorophyll fluorescence. However for far-range measurements, atmospheric effects also modify this shape. In this study, measurements in O 2 -A and O 2 -B absorption bands have been performed at different altitudes up to 3123 m over bare soil and wheat fields. It is observed that bands depth increase significantly with altitude. In O 2 -B band, the total magnitude of variation is of the same order of magnitude as the change induced by vegetation fluorescence, while it is much greater in O 2 -A band. We used MODTRAN 4 to correct measurements fr…
Shear Induced Demixing and Rheological Behavior of Aqueous Solutions of Poly(N-isopropylacrylamide)
2003
The interrelation between the phase separation behavior and the rheological performance of aqueous solutions of high molecular weight (M w = 1 600 kg/mol) poly(N-isopropylacrylamide) was investigated. The system demixes upon heating and the cloud point temperature, T cp decreases steadily with rising polymer concentration up to 10 wt.-%. The application of shear supports phase separation and reduces T cp markedly. This observation is interpreted in terms of destruction of intersegmental clusters formed in the quiescent state owing to favorable interactions. Intrinsic viscosities and Huggins coefficients as well as the viscosities, η at higher polymer concentrations are closely connected wit…