23 research outputs found
Investigation of radar backscattering from second-year sea ice
The scattering properties of second-year ice were studied in an experiment at Mould Bay in April 1983. Radar backscattering measurements were made at frequencies of 5.2, 9.6, 13.6, and 16.6 GHz for vertical polarization, horizontal polarization and cross polarizations, with incidence angles ranging from 15 to 70 deg. The results indicate that the second-year ice scattering characteristics were different from first-year ice and also different from multiyear ice. The fading properties of radar signals were studied and compared with experimental data. The influence of snow cover on sea ice can be evaluated by accounting for the increase in the number of independent samples from snow volume with respect to that for bare ice surface. A technique for calculating the snow depth was established by this principle and a reasonable agreement has been observed. It appears that this is a usable way to measure depth in snow or other snow-like media using radar
Optical magnetic response in three-dimensional metamaterial of upright plasmonic meta-molecules
We report the first three-dimensional photonic metamaterial, an array of erected U-shape plasmonic gold meta-molecules, that exhibits a profound response to the magnetic field of light incident normal to the array. The metamaterial was fabricated using a double exposure e-beam lithographic process. It was investigated by optical measurements and finite-element simulations, and showed that the magnetic field solely depends on the plasmonic resonance mode showing either enhanced in the centre of the erected U-shape meta-molecule (16 times enhancement) or enhanced around two prongs of erected U-shape meta-molecule (4 times enhancement)
Effect of copper on the performance and bacterial communities of activated sludge using Illumina MiSeq platforms
High-Efficiency Broadband Anomalous Reflection by Gradient Meta-Surfaces
We combine theory and experiment to demonstrate that
a carefully
designed gradient meta-surface supports high-efficiency anomalous
reflections for near-infrared light following the generalized Snell’s
law, and the reflected wave becomes a bounded surface wave as the
incident angle exceeds a critical value. Compared to previously fabricated
gradient meta-surfaces in infrared regime, our samples work in a shorter
wavelength regime with a broad bandwidth (750–900 nm), exhibit
a much higher conversion efficiency (∼80%) to the anomalous
reflection mode at normal incidence, and keep light polarization unchanged
after the anomalous reflection. Finite-difference-time-domain (FDTD)
simulations are in excellent agreement with experiments. Our findings
may lead to many interesting applications, such as antireflection
coating, polarization and spectral beam splitters, high-efficiency
light absorbers, and surface plasmon couplers
A Prospective, Randomized Trial of Intravenous Glucocorticoids Therapy With Different Protocols for Patients With Graves' Ophthalmopathy
Effect of Hg2+doping and of the annealing temperature on the nanostructural properties of TiO2 thin films obtained by sol–gel method
p38 MAP kinase–dependent phosphorylation of the Gp78 E3 ubiquitin ligase controls ER–mitochondria association and mitochondria motility
High-Throughput Discovery of Chloroplast and Mitochondrial DNA Polymorphisms in Brassicaceae Species by ORG-EcoTILLING
CEPC Conceptual Design Report: Volume 2 - Physics & Detector
The Circular Electron Positron Collider (CEPC) is a large international scientific facility proposed by the Chinese particle physics community to explore the Higgs boson and provide critical tests of the underlying fundamental physics principles of the Standard Model that might reveal new physics. The CEPC, to be hosted in China in a circular underground tunnel of approximately 100 km in circumference, is designed to operate as a Higgs factory producing electron-positron collisions with a center-of-mass energy of 240 GeV. The collider will also operate at around 91.2 GeV, as a Z factory, and at the WW production threshold (around 160 GeV). The CEPC will produce close to one trillion Z bosons, 100 million W bosons and over one million Higgs bosons. The vast amount of bottom quarks, charm quarks and tau-leptons produced in the decays of the Z bosons also makes the CEPC an effective B-factory and tau-charm factory. The CEPC will have two interaction points where two large detectors will be located. This document is the second volume of the CEPC Conceptual Design Report (CDR). It presents the physics case for the CEPC, describes conceptual designs of possible detectors and their technological options, highlights the expected detector and physics performance, and discusses future plans for detector R&D and physics investigations. The final CEPC detectors will be proposed and built by international collaborations but they are likely to be composed of the detector technologies included in the conceptual designs described in this document. A separate volume, Volume I, recently released, describes the design of the CEPC accelerator complex, its associated civil engineering, and strategic alternative scenarios