788 research outputs found
Experimental investigation of high temperature thermal contact resistance with interface material
Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.Thermal contact resistance plays a very important role in
heat transfer efficiency and thermomechanical coupling
response between two materials, and a common method to
reduce the thermal contact resistance is to fill a soft interface
material between these two materials. A testing system of high
temperature thermal contact resistance based on INSTRON
8874 is established in the present paper, which can achieve 600
Celsius degree at the interface. Based on this system, the
thermal contact resistance between superalloy GH600 material
and three-dimensional braid C/C composite material are
experimentally investigated, under different interface pressures,
interface roughness and temperatures, respectively. At the same
time, the mechanism of reducing the thermal contact resistance
with carbon fiber sheet as interface material is experimentally
investigated. Results show that the present testing system is
feasible in the experimental research of high temperature
thermal contact resistancedc201
The effect of applied electric field on pulsed radio frequency and pulsed direct current plasma jet array
Here we compare the plasma plume propagation characteristics of a 3-channel pulsed RF plasma jet array and those of the same device operated by a pulsed dc source. For the pulsed-RF jet array, numerous long life time ions and metastables accumulated in the plasma channel make the plasma plume respond quickly to applied electric field. Its structure similar as “plasma bullet” is an anode glow indeed. For the pulsed dcplasma jet array, the strong electric field in the vicinity of the tube is the reason for the growing plasma bullet in the launching period. The repulsive forces between the growing plasma bullets result in the divergence of the pulsed dcplasma jet array. Finally, the comparison of 309 nm and 777 nm emissions between these two jet arrays suggests the high chemical activity of pulsed RF plasma jet array
Variants in the fetal genome near pro-inflammatory cytokine genes on 2q13 associate with gestational duration
The duration of pregnancy is influenced by fetal and maternal genetic and non-genetic
factors. Here we report a fetal genome-wide association meta-analysis of gestational duration, and early preterm, preterm, and postterm birth in 84,689 infants. One locus on chromosome 2q13 is associated with gestational duration; the association is replicated in 9,291
additional infants (combined P = 3.96 × 10−14). Analysis of 15,588 mother-child pairs shows
that the association is driven by fetal rather than maternal genotype. Functional experiments
show that the lead SNP, rs7594852, alters the binding of the HIC1 transcriptional repressor.
Genes at the locus include several interleukin 1 family members with roles in proinflammatory pathways that are central to the process of parturition. Further understanding
of the underlying mechanisms will be of great public health importance, since giving birth
either before or after the window of term gestation is associated with increased morbidity
and mortalit
Electrical transport and magnetic properties of nanostructured La0.67Ca0.33MnO3
Nanostructured La0.67Ca0.33MnO3 (NS-LCMO) was formed by pulsed-laser
deposition on the surface of porous Al2O3. The resistance peak temperature (Tp)
of the NS-LCMO increases with increasing average thickness of the films, while
their Curie temperatures (Tc) remain unchanged. The coercive field of the
samples increases with decreasing film thickness and its temperature dependence
can be well described by Hc(T) = Hc(0)[1-(T/TB)1/2]. A large magnetoresistance
and strong memory effect were observed for the NS-LCMO. The results are
discussed in terms of the size effect, Coulomb blockade and magnetic tunneling
effect. This work also demonstrates a new way to get nanostructured manganites
Partial wave analysis of J/\psi \to \gamma \phi \phi
Using events collected in the BESII detector, the
radiative decay is
studied. The invariant mass distribution exhibits a near-threshold
enhancement that peaks around 2.24 GeV/.
A partial wave analysis shows that the structure is dominated by a
state () with a mass of
GeV/ and a width of GeV/. The
product branching fraction is: .Comment: 11 pages, 4 figures. corrected proof for journa
A probabilistic method for the operation of three-phase unbalanced active distribution networks
YesThis paper proposes a probabilistic multi-objective optimization method for the operation of three-phase distribution networks incorporating active network management (ANM) schemes including coordinated voltage control and adaptive power factor control. The proposed probabilistic method incorporates detailed modelling of three-phase distribution network components and considers different operational objectives. The method simultaneously minimizes the total energy losses of the lines from the point of view of distribution network operators (DNOs) and maximizes the energy generated by photovoltaic (PV) cells considering ANM schemes and network constraints. Uncertainties related to intermittent generation of PVs and load demands are modelled by probability density functions (PDFs). Monte Carlo simulation method is employed to use the generated PDFs. The problem is solved using ɛ-constraint approach and fuzzy satisfying method is used to select the best solution from the Pareto optimal set. The effectiveness of the proposed probabilistic method is demonstrated with IEEE 13- and 34- bus test feeders
Measurements of the observed cross sections for exclusive light hadrons containing at , 3.650 and 3.6648 GeV
By analyzing the data sets of 17.3, 6.5 and 1.0 pb taken,
respectively, at , 3.650 and 3.6648 GeV with the BES-II
detector at the BEPC collider, we measure the observed cross sections for
, , ,
and at the three energy
points. Based on these cross sections we set the upper limits on the observed
cross sections and the branching fractions for decay into these
final states at 90% C.L..Comment: 7 pages, 2 figure
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