64,308 research outputs found
Effects of the thermal sterilization procedure on polymeric products
Properties of samples are tested, after thermal exposure, and values are compared with unexposed samples. Thermal stability or compatibility ratings of formulated or compounded organic polymers using trade names are made and degree of change in measured properties is assessed. Products are rated compatible, marginal, or not compatible
Effects of the thermal sterilization procedure on polymeric products
Effects of thermal sterilization on polymeric products used on Ranger and Mariner spacecraf
Time- and frequency-domain polariton interference
We present experimental observations of interference between an atomic spin
coherence and an optical field in a {\Lambda}-type gradient echo memory. The
interference is mediated by a strong classical field that couples a weak probe
field to the atomic coherence through a resonant Raman transition. Interference
can be observed between a prepared spin coherence and another propagating
optical field, or between multiple {\Lambda} transitions driving a single spin
coherence. In principle, the interference in each scheme can yield a near unity
visibility.Comment: 11 pages, 5 figure
Estimating Lunar Pyroclastic Deposit Depth from Imaging Radar Data: Applications to Lunar Resource Assessment
Lunar pyroclastic deposits represent one of the primary anticipated sources of raw materials for future human settlements. These deposits are fine-grained volcanic debris layers produced by explosive volcanism contemporaneous with the early stage of mare infilling. There are several large regional pyroclastic units on the Moon (for example, the Aristarchus Plateau, Rima Bode, and Sulpicius Gallus formations), and numerous localized examples, which often occur as dark-halo deposits around endogenic craters (such as in the floor of Alphonsus Crater). Several regional pyroclastic deposits were studied with spectral reflectance techniques: the Aristarchus Plateau materials were found to be a relatively homogeneous blanket of iron-rich glasses. One such deposit was sampled at the Apollo 17 landing site, and was found to have ferrous oxide and titanium dioxide contents of 12 percent and 5 percent, respectively. While the areal extent of these deposits is relatively well defined from orbital photographs, their depths have been constrained only by a few studies of partially filled impact craters and by imaging radar data. A model for radar backscatter from mantled units applicable to both 70-cm and 12.6-cm wavelength radar data is presented. Depth estimates from such radar observations may be useful in planning future utilization of lunar pyroclastic deposits
Single vortex fluctuations in a superconducting chip as generating dephasing and spin flips in cold atom traps
We study trapping of a cold atom by a single vortex line in an extreme type
II superconducting chip, allowing for pinning and friction. We evaluate the
atom's spin flip rate and its dephasing due to the vortex fluctuations in
equilibrium and find that they decay rapidly when the distance to the vortex
exceeds the magnetic penetration length. We find that there are special spin
orientations, depending on the spin location relative to the vortex, at which
spin dephasing is considerably reduced while perpendicular directions have a
reduced spin flip rate. We also show that the vortex must be perpendicular to
the surface for a general shape vortex.Comment: 6 pages, 4 figure
1999-00 Illinois Trapper Survey Report
Federal Aid Project Number W-112-R-9, Job Number 101.2, Wildlife Restoration FundReport issued on: January 5, 200
Providing decision support for the condition-based maintenance of circuit breakers through data mining of trip coil current signatures
The focus of this paper centers on the condition assessment of 11kV-33kV distribution circuit breakers from the analysis of their trip coil current signatures captured using an innovative condition monitoring technology developed by others. Using available expert knowledge in conjunction with a structured process of data mining, thresholds associated with features representing each stage of a circuit breaker's operation may be defined and used to characterize varying states of circuit breaker condition. Knowledge and understanding of satisfactory and unsatisfactory breaker condition can be gained and made explicit from the analysis of captured trip signature data and subsequently used to form the basis of condition assessment and diagnostic rules implemented in a decision support system, used to inform condition-based decisions affecting circuit breaker maintenance. This paper proposes a data mining method for the analysis of condition monitoring data, and demonstrates this method in its discovery of useful knowledge from trip coil data captured from a population of SP Power System's in-service circuit breakers. This knowledge then forms the basis of a decision support system for the condition assessment of these circuit breakers during routine trip testing
Androgen Receptor and Vasopressin Receptor (AVPR1a) Genetic Polymorphisms are not associated with Marital Status or Fertility among Ariaal Men of Northern Kenya
A growing body of scholarship implicates testosterone and vasopressin in male reproductive behavior, including in humans. Since hormones exert their effects through their respective receptors, an open question has been whether genetic polymorphisms in the androgen receptor and vasopressin 1a receptor (AVPR1a) impact human male social behavior. Here, we sought to test for associations between polymorphisms in the coding region of the androgen receptor and promoter region of AVPR1a in relation to marital status and fertility among pastoralist Ariaal men of northern Kenya. None of the three polymorphisms were related to marital status (single, monogamously married, polygynously married) or fertility (number of current living children). We discuss these null findings in light of existing data
Extended Scaling for the high dimension and square lattice Ising Ferromagnets
In the high dimension (mean field) limit the susceptibility and the second
moment correlation length of the Ising ferromagnet depend on temperature as
chi(T)=tau^{-1} and xi(T)=T^{-1/2}tau^{-1/2} exactly over the entire
temperature range above the critical temperature T_c, with the scaling variable
tau=(T-T_c)/T. For finite dimension ferromagnets temperature dependent
effective exponents can be defined over all T using the same expressions. For
the canonical two dimensional square lattice Ising ferromagnet it is shown that
compact "extended scaling" expressions analogous to the high dimensional limit
forms give accurate approximations to the true temperature dependencies, again
over the entire temperature range from T_c to infinity. Within this approach
there is no cross-over temperature in finite dimensions above which
mean-field-like behavior sets in.Comment: 6 pages, 6 figure
Effects of ethylene oxide-Freon 12 decontamination and dry heat sterilization procedures on polymeric products
Effects of ethylene oxide-Freon 12 decontamination and dry heat sterilization procedures on potential spacecraft polymeric material
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