[en] On August 24, 2016, an earthquake of magnitude 6.2 struck Central Italy (42.706°N and 13.223°E) at 1:36 UT. We present the results obtained from the US Navy VLF Transmitter’s NSY signal of 45.9 kHz transmitted from Niscemi, in the province of Sicily, Italy and received at the Kiel Longwave Monitor, Germany for 2016. We analysed the terminator times and their individual differences. We also analysed trends, dispersion and night time fluctuation which gave us a possible precursor the Italy earthquake. We found ionospheric perturbations in these parameters on 14th, 19th and 22nd of August, few days prior. Moreover, we filtered the possible effects due to lightning, storms and auroras if any.

[en] We report construction of an iodine-stabilized laser frequency standard at 532 nm based on modulation transfer spectroscopy (MTS) technology with good reproducibility. A frequency stability of 2.5 × 10⁻¹⁴ at 1 s averaging time is achieved, and the frequency reproducibility has a relative uncertainty of 3.5 × 10⁻¹³, demonstrating the great stability of our setup. The systematic uncertainty of the iodine-stabilized laser frequency standard is evaluated, especially the contribution of the residual amplitude modulation (RAM). The contribution of the RAM in MTS cannot be evaluated directly. To solve this problem, we theoretically deduce the MTS signal with RAM under large modulation depth, and prove that the non-symmetric shape of the MTS signal is directly related to the MTS effect. The non-symmetric shape factor r can be calibrated with a frequency comb, and in real experiments, this r value can be obtained by least-squares fitting of the MTS signal, from which we can infer the RAMinduced frequency shift. The full frequency uncertainty is evaluated to be 5.3 kHz (corresponding to a relative frequency uncertainty of 9.4 × 10⁻¹²). The corrected transition frequency has a difference from the BIPM-recommended value of 2 kHz, which is within 1 σ uncertainty, proving the validity of our evaluation. (paper)

[en] Uranium mineralisation is reported in the basement fracture if Sambalpur granitoids in Dulapali area of Raigarh district, M.P. VLF-EM surveys are conducted using Scintrex IGS-2/ VLF-4 equipment to demarcate the spatial locations of these fractures filled with ferruginous breccia of magnetite, hematite, ilmetite, pyrite and chalcopyrite vis-a-vis, the EM conductors. Three parameters - vertical in-phase (DZR), vertical out-of-phase (DZI) normalised by horizontal magnetic field (Hy) and VLF-EM resistivity (r_a) are recorded and analysed. (author)

[en] Extensive research has been carried out over the years to reduce the acoustic noise resulting from vibration of electromagnetic cores mainly caused by magnetostriction. This paper presents the results of a basic experimental study of magnetostriction in strips of grain oriented electrical steel commonly used in electromagnetic cores which gives an important new understanding of the phenomenon. Results suggest that a transformer core assembled from laminations of grain-oriented electrical steel around 0.3 m long would resonate at a magnetising frequency of 1.5 kHz which could result in excessive vibration and noise

No abstract available

[en] This paper presents series efforts to lower resistance of bakelite electrode plate to improve the RPC capability under high rate working condition. New bakelite material with alkali metallic ion doping has been manufactured and tested. This bakelite is found unstable under large charge flux and need further investigation. A new structure of carbon-embedded bakelite RPC has been developed, which can reduce the effective resistance of electrode by a factor of 10. The prototype of the carbon-embedded chamber could function well under gamma radiation source at event rate higher than 10 kHz/cm"2. The preliminary tests show that this kind of new structure performs as efficiently as traditional RPCs

[en] A new type of micromachined vertically deformable varying-pitch grating is designed and fabricated. Its characterization and its feasibility as a spectrometer are presented. The deformable grating shows a 0.7 µm working range and 3.6 kHz bandwidth. Its characterization and its feasibility as a spectrometer are presented. The varying-pitch grating has the ability to detect an individual wavelength with a single detector by physical scanning. Its deformable capability can increase intensity and resolution at a specific wavelength. Those two capabilities are experimentally demonstrated

[en] A two-phase magnetoelectric (ME) parallel sandwich was developed by bonding two longitudinally magnetized Terfenol-D/epoxy pseudo-1-3 magnetostrictive composite plates on two longitudinally polarized PZT/epoxy 2-2 piezoelectric composite plates combined longitudinally as a single plate and with their polarization directions arranged in reverse directions. A significantly large ME voltage sensitivity (ME _V ) of 3.1 V/Oe was observed at the resonance frequency of 42.8 kHz under a relatively low bias field of 0.8 kOe. This resonance ME _V was ∼35 times larger than its nonresonance values, showing great promise of using the proposed sandwich in ME conversion devices

[en] This paper presentsseries efforts to lower resistance of bakelite electrode plate to improve the RPC capability under high rate working condition. New bakelite material with alkali metallic ion doping has been manufactured and tested. This bakelite is found unstable under large charge flux and need further investigation. Alternatively, a new structure of carbon-embedded bakelite RPC has been developed, which can reduce the effective resistance of electrode by a factor of 10. The prototype of the carbon-embedded chamber could function well under gamma radiation source at event rate higher than 10 kHz/cm². The preliminary tests show that this kind of new structure performs as efficiently as traditional RPCs

[en] We consider an ultracold plasma that has bosonic ions, at zero temperature. Assuming that ions are trapped by a harmonic trap, we calculate the size of the cloud for both screened and bare Coulomb interactions. Our results indicate that if clouds containing around 10⁴ ions are confined with a trapping frequency of 10 kHz, stable radius is 15 μm for a fully screened two-component plasma while the radius increases to 2 mm for a one component plasma