Spin echo in spinor dipolar Bose-Einstein condensates

We theoretically propose and numerically realize spin echo in a spinor Bose--Einstein condensate (BEC). We investigate the influence on the spin echo of phase separation of the condensate. The equation of motion of the spin density exhibits two relaxation times. We use two methods to separate the relaxation times and hence demonstrate a technique to reveal magnetic dipole--dipole interactions in spinor BECs.Comment: 4 pages, 5 figure

Analisis Kualitatif Zat Bioaktif Pada Ekstrak Daun Alpukat (Persea Americana Mill) Dan Uji Praklinis Dalam Menurunkan Kadar Glukosa Darah Pada Mencit (Mus Musculus)

Diabetes is the oldest disease in the world, the death rate cause by diabetes mellitus is increasing. This study aims to know bioactive substances of avocado leaf and effective concentrate in decreasing the level of mice blood glucose. The study apply experimetal method to analyze bioactive substance in avocado leaf extract qualitatively. Whereas the preclinical testing use random group design. This study used 15 male mice as test animal which are induced with etilen diamin tetra asetat (EDTA). The mice are divided into 5 groups (n=5) randomly with different treatment. Treatment I, II, III are given avocado leaf extarct each with concentrate of 10%, 20% and 40%, treatment IV is given suspension of glibenklamid as a positive control (+) and treatment V is given 1% suspension of sodium carboxymethil cellulose (Na-CMC) as a negative control (-). Data obtained is analysed by using statistical analysis of varians (ANOVA) wich is continued with Duncan test. The research result shows that advocado leaf extract positively contains compounds of alkaloid, flavonoid, saponin, tanin and steroid. Praclinic test shows that advocado leaf extract proven can lower the level of mice glucose and relatively the most effective concentrate is 10%

Pengembangan Model Latihan Teknik Dasar Shooting Permainan Sepakbola Usia 12-15 Tahun pada Peserta Kegiatan Ekstrakurikuler SMP

Development Model Basic Training Soccer Game Shooting of Age 12-15 Years on Participants Junior High School Extracurricular Activities.This research aims at developing a model training basic techniques of shooting football games, aged 12-15 years. The subject of the research were students joining extracurricular in Junior High School 1 Blitar. The study used research and development design by Gall and Borg that was adapted into: 1) determining the potential and the problems of research; 2) collecting the information: (a) examining the references, (b) needs analysis; 3) designing products; 4) designing validation, testing football experts (2); 5) improving or revising design; 6) trials phase I (small groups of 6 people); 7 revising II); 8) phase II trial (a large group of 24 persons); 9) final product development. The descriptive analysis was used tp analyze the data. Expert evaluation of football on the results of the needs analysis to testing is 90%, the test results of the phase I tryout for small groups obtained 84.16%, test results for phase II field tryout retrieved results 89.58%. It showed the development of this model was appropriate. The evaluation of media experts obtained 90%, so this shooting exercise model book is appropriate to be used

Vortex Multiplication in Applied Flow: the Precursor to Superfluid Turbulence

The dynamics of quantized vortices in rotating $^3$He-B is investigated in the low density (single-vortex) regime as a function of temperature. An abrupt transition is observed at $0.5 T_{\rm c}$. Above this temperature the number of vortex lines remains constant, as they evolve to their equilibrium positions. Below this temperature the number of vortices increases linearly in time until the vortex density has grown sufficiently for turbulence to switch on. On the basis of numerical calculations we suggest a mechanism responsible for vortex formation at low temperatures and identify the mutual friction parameter which governs its abrupt temperature dependence.Comment: 5 pages, 4 figures; version submitted to Phys. Rev. Let

Superconducting Nb-film LC resonator

Sputtered Nb thin-film LC resonators for low frequencies at 0.5 MHz have been fabricated and tested in the temperature range 0.05--1 K in magnetic fields up to 30 mT. Their Q value increases towards decreasing temperature as sqrt(T) and reaches 10^3 at 0.05 K. As a function of magnetic field Q is unstable and displays variations up to 50%, which are reproducible from one field sweep to the next. These instabilities are attributed to dielectric losses in the plasma deposited SiO_2 insulation layer, since the thin-film coil alone reaches a Q > 10^5 at 0.05 K.Comment: 6 pages, 7 figures, submitted to Review of Scientific Instrument

First global observations of the mesospheric potassium layer

Metal species, produced by meteoric ablation, act as useful tracers of upper atmosphere dynamics and chemistry. Of these meteoric metals, K is an enigma: at extratropical latitudes, limited available lidar data show that the K layer displays a semiannual seasonal variability, rather than the annual pattern seen in other metals such as Na and Fe. Here we present the first near-global K retrieval, where K atom number density profiles are derived from dayglow measurements made by the Optical Spectrograph and Infrared Imager System spectrometer on board the Odin satellite. This robust retrieval produces density profiles with typical layer peak errors of ±15% and a 2 km vertical grid resolution. We demonstrate that these retrieved profiles compare well with available lidar data and show for the first time that the unusual semiannual behavior is near-global in extent. This new data set has wider applications for improving understanding of the K chemistry and of related upper atmosphere processes

Diurnal variation of the potassium layer in the upper atmosphere

Measurements of the diurnal cycle of potassium (K) atoms between 80 and 110km have been made during October (for the years 2004–2011) using a Doppler lidar at Kühlungsborn, Germany (54.1°N,11.7°E). A pronounced diurnal variation is observed in the K number density, which is explored by using a detailed description of the neutral and ionized chemistry of K in a three-dimensional chemistry climate model. The model captures both the amplitude and phase of the diurnal and semidiurnal variability of the layer, although the peak diurnal amplitude around 90 kmis overestimated. Themodel shows that the total potassium density (≈K+K++KHCO3) exhibits little diurnal variation at each altitude, and the diurnal variations are largely driven by photochemical conversion between these reservoir species. In contrast, tidally driven vertical transport has a small effect at this midlatitude location, and diurnal fluctuations in temperature are of little significance because they are small and the chemistry of K is relatively temperature independent

Propagation of first sound in liquid 3He

The dispersion of first (hydrodynamic) sound in normalfluid and superfluid 3He has been measured in a cylindrical resonator at a pressure of 18.8 bar in the frequency range between 85 kHz and 227 kHz and in the temperature range between 1.2 and 50 mK. The sound velocity measured in the normalfluid regime confirms recent theories of the slip effect in Fermi liquids; in superfluid 3He-B we find qualitative agreement between experiment and theoretical sound velocity