2,084 research outputs found
Optimization design for ultrasonic horn with large amplitude based on genetic algorithm
With the functions of amplitude amplification, impedance matching and protecting the transducer in ultrasonic machining system, ultrasonic horn is an important component in design of power ultrasonic vibration system. A new horn with large amplitude is designed. The profile of the horn is a cubic Bezier Curve. Based on genetic algorithm, the horn with large vibration amplitude ratio was obtained by optimizing the control points at the starting point and the end point of Bezier Curve. Simulation comparison was also carried out on the vibration performances of other four kinds of horns. Bezier horn and conical horn were manufactured by numerical control (NC) technology, in addition, measurement and comparison were carried out on their performances by combining with a vibrator. Results show that the amplitude of the optimized Bezier horn is 73.5 % larger than that of conical horn. Under the excitation voltage of 200 Vp-p, the amplitude of the Bezier horn can reach 108 µm
TLE3 represses colorectal cancer proliferation by inhibiting MAPK and AKT signaling pathways
Primer Sequences used for RT-qPCR (5â to 3â). (DOCX 13 kb
5,6-Dihydro-1,10-phenanthroline-1,10-diium μ-oxido-bis[pentafluoridotantalate(V)]
In the title compound, (C12H12N2)[Ta2F10O], the doubly protonated 5,6-dihydro-1,10-phenantroline-1,10-diium cation is located on a twofold rotation axis, whereas the isolated [Ta2OF10]2− dianion has -1 symmetry. In the so far unknown dianion, the symmetry-related TaV atoms are octahedrally coordinated by five F atoms and a bridging O atom, the latter being located on an inversion centre. The two pyridine rings in the cation make a dihedral angle of 22.8 (4)°. The cations and dianions are arranged in layers parallel to (100) and are connected through N—H⋯F and C—H⋯F hydrogen-bonding interactions into a three-dimensional structure
The LAMOST Survey of Background Quasars in the Vicinity of the Andromeda and Triangulum Galaxies -- II. Results from the Commissioning Observations and the Pilot Surveys
We present new quasars discovered in the vicinity of the Andromeda and
Triangulum galaxies with the LAMOST during the 2010 and 2011 observational
seasons. Quasar candidates are selected based on the available SDSS, KPNO 4 m
telescope, XSTPS optical, and WISE near infrared photometric data. We present
509 new quasars discovered in a stripe of ~135 sq. deg from M31 to M33 along
the Giant Stellar Stream in the 2011 pilot survey datasets, and also 17 new
quasars discovered in an area of ~100 sq. deg that covers the central region
and the southeastern halo of M31 in the 2010 commissioning datasets. These 526
new quasars have i magnitudes ranging from 15.5 to 20.0, redshifts from 0.1 to
3.2. They represent a significant increase of the number of identified quasars
in the vicinity of M31 and M33. There are now 26, 62 and 139 known quasars in
this region of the sky with i magnitudes brighter than 17.0, 17.5 and 18.0
respectively, of which 5, 20 and 75 are newly-discovered. These bright quasars
provide an invaluable collection with which to probe the kinematics and
chemistry of the ISM/IGM in the Local Group of galaxies. A total of 93 quasars
are now known with locations within 2.5 deg of M31, of which 73 are newly
discovered. Tens of quasars are now known to be located behind the Giant
Stellar Stream, and hundreds behind the extended halo and its associated
substructures of M31. The much enlarged sample of known quasars in the vicinity
of M31 and M33 can potentially be utilized to construct a perfect astrometric
reference frame to measure the minute PMs of M31 and M33, along with the PMs of
substructures associated with the Local Group of galaxies. Those PMs are some
of the most fundamental properties of the Local Group.Comment: 26 pages, 6 figures, AJ accepte
Iohexol Degradation by Biogenic Palladium Nanoparticles Hosted in Anaerobic Granular Sludge
To improve the degradation ability of anaerobic granular sludge (AGS) toward the iodinated contrast media (ICM) iohexol, biogenic nanoscale palladium (Pd) was formed in AGS via microbial reduction. The Pd hosted in AGS (Pd-AGS) was used for iohexol degradation. The effects of the electron donor, reaction medium, iodide ion fouling, and polymer embedding of the Pd-AGS on the reactivity were investigated. Our results showed the Pd-AGS increased the degradation rate of iohexol, with a conversion rate constant increased by 86.3-fold compared to the AGS control. Various organic compounds were investigated as electron donors to initiate the catalytic activity of Pd-AGS and the promotion achieved with the tested electron donors was in the following order: formate > lactate > ethanol > glucose > acetate. The Pd-AGS had high reactivity in deionized water at mild pH, and almost no reactivity under acidic (pH = 1.2) and alkaline (pH > 11) conditions. The presence of iodide ions in the medium inhibited the catalytic activity of Pd-AGS toward iohexol because of catalyst fouling. Embedding the Pd-AGS in alginate, chitosan, or polyvinyl alcohol (PVA) could prevent Pd loss but it also retarded the iohexol degradation rate. The Pd-AGS, as a combination of Pd catalyst and AGS, provides a novel strategy for iohexol degradation in polluted water and wastewater
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