average dispersion
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Author(s):  
Mevi Irianti Tonapa ◽  
Rani Dewi Pratiwi ◽  
Elsye Gunawan

Kenop Flower (Gomphrena globosa L.) is used in the manufacture of lip cream because contains betacyanin pigments that function as color pigments. This study aims to determine the physical quality and stability of the lip cream preparation of the ethanol extract of kenop flower (Gomphrena globosa L.). This research was conducted experimentally, including the manufacture of lip cream formulations with ethanol extract of kenop flower (Gomphrena globosa L.) with a concentration of 10%. The results of the physical examination test for lip cream preparations for all preparations have a distinctive vanilla aroma with a semi-solid texture, F0 has ivory white color and F1-F3 has a brown color. The preparations had a homogeneous composition, average pH 6-7, had good greasing power, 5.0-5.8 average dispersion and 60.33-66.67 seconds average adhesion. The stability test carried out on day 28 found that all preparations were stable, had a distinctive vanilla aroma with a semi-solid texture, F0 had ivory white color and F1-F3 had a brown color. The preparation has a homogeneous composition; the average pH is 6-7. Where the lip cream formulas F1 and F3 decreased the pH value on the 28th day from 7 to 6 but tended to be stable and in the pH range that matched the lip pH. And there is no phase separation in all formulas.


2021 ◽  
Author(s):  
Chiara Colombero ◽  
Myrto Papadopoulou ◽  
Tuomas Kauti ◽  
Pietari Skyttä ◽  
Emilia Koivisto ◽  
...  

Abstract. Surface wave (SW) methods are ideal candidates for an effective and sustainable development of seismic exploration, but still remain under-exploited in hard rock sites. We present a successful application of active and passive surface wave tomography for the characterization of the southern continuation of the Siilinjärvi phosphate deposit (Finland). A semi-automatic workflow for the extraction of the path-average dispersion curves (DCs) from ambient seismic noise data is proposed, including identification of time windows with strong coherent SW signal, azimuth analysis and two-station method for DC picking. DCs retrieved from passive data are compared with active SW tomography results recently obtained at the site. Passive data are found to carry information at longer wavelengths, thus extending the investigation depth. Active and passive DCs are consequently inverted together to retrieve a deep pseudo-3D shear-wave velocity model for the site, with improved resolution. The seismic results are compared with the latest available geological models to both validate the proposed workflow and improve the interpretation of the geometry, extent and contacts of the mineralization. Important large-scale geological boundaries and structural discontinuities are recognized from the results, demonstrating the effectiveness and advantages of the methods for mineral exploration perspectives.


2021 ◽  
Author(s):  
Tak Ho ◽  
Keith Priestley ◽  
Eric Debayle

<p>We present a new radially anisotropic (<strong>ξ)</strong> tomographic model for the upper mantle to transition zone depths derived from a large Rayleigh (~4.5 x 10<sup>6 </sup>paths) and Love (~0.7 x 10<sup>6</sup> paths) wave path average dispersion curves with periods of 50-250 s and up to the fifth overtone. We first extract the path average dispersion characteristics from the waveforms. Dispersion characteristics for common paths (~0.3 x 10<sup>6</sup> paths) are taken from the Love and Rayleigh datasets and jointly inverted for isotropic V<sub>s </sub>and <strong>ξ</strong>. CRUST1.0 is used for crustal corrections and a model similar to PREM is used as a starting model. V<sub>s</sub> and <strong>ξ</strong> are regionalised for a 3D model. The effects of azimuthal anisotropy are accounted for during the regionalisation. Our model confirms large-scale upper mantle features seen in previously published models, but a number of these features are better resolved because of the increased data density of the fundamental and higher modes coverage from which our <strong>ξ</strong>(z) was derived. Synthetic tests show structures with radii of 400 km can be distinguished easily. Crustal perturbations of +/-10% to V<sub>p</sub>, V<sub>s</sub> and density, or perturbations to Moho depth of +/-10 km over regions of 400 km do not significantly change the model. The global average decreases from <strong>ξ~</strong>1.06 below the Moho to <strong>ξ</strong>~1 at ~275 km depth. At shallow depths beneath the oceans <strong>ξ</strong>>1 as is seen in previously published global mantle radially anisotropic models. The thickness of this layer increases slightly with the increasing age of the oceanic lithosphere. At ~200 km and deeper depths below the fast-spreading East Pacific Rise and starting at somewhat greater depths beneath the slower spreading ridges, <strong>ξ</strong><1. At depths ≥200 km and deeper depths below most of the backarc basins of the western Pacific <strong>ξ</strong><1. The signature of mid-ocean ridges vanishes at about 150 km depth in V<sub>s</sub> while it extends much deeper in the <strong>ξ</strong> model suggesting that upwelling beneath mid-ocean ridges could be more deeply rooted than previously believed. The pattern of radially anisotropy we observe, when compared with the pattern of azimuthal anisotropy determined from Rayleigh waves, suggests that the shearing at the bottom of the plates is only sufficiently strong to cause large-scale preferential alignment of the crystals when the plate motion exceeds some critical value which Debayle and Ricard (2013) suggest is about 4 cm/yr.</p>


2021 ◽  
Author(s):  
Daniela Teodor ◽  
Charles Beard ◽  
Laura Alejandra Pinzon-Rincon ◽  
Aurélien Mordret ◽  
François Lavoué ◽  
...  

<p>Ambient noise surface wave tomography (ANSWT) is an environmentally friendly and cost-effective technique for subsurface imaging. In this study, we used natural (low-frequency) and anthropogenic (high-frequency) noise sources to map the velocity structure of the Marathon Cu-PGE deposit (Ontario, Canada) to a depth of 1 km. The Marathon deposit is a circular (ø = 25 km) alkaline intrusion comprising gabbros at the rim and an overlying series of syenites in the centre. Cu-PGE mineralisation is hosted by gabbros close to the inward-dipping footwall of the intrusion. The country rocks are Archaean volcanic breccias that are seismically slower than the gabbros, and similar in velocity to the syenites. We used ANSWT to image the footwall contact that controls the location of the mineralisation.</p><p>An array of 1024 vertical-component receivers were deployed for 30 days to record ambient noise required for surface wave analysis. Two overlapping grids were used: a 200 m x 6040 m dense array with node spacing of 50 m, and a 2500 m x 4000 m sparse array with node spacing of 150 m.  The signal was down-sampled to 50 Hz, divided into segments of 30 minutes, cross-correlated and stacked. Surface wave analysis was conducted over the dense array and the sparse array data. We considered the fundamental mode of Rayleigh wave propagation for our frequency-wavenumber (F-K) analysis and focused on the phase velocity variation in the high-frequency ambient noise signal (up to 22 Hz). We reconstructed the shallow structure with progressively increased resolution using surface wave dispersion curves extracted from receiver arrays divided into segments of variable lengths. Several average dispersion curves were computed from individual dispersion curves belonging to different seismic lines. Each average dispersion curve was inverted to obtain S-wave velocity models using an McMC transdimensional Bayesian approach.</p><p>The tomographic images reveal a shallow high-velocity anomaly, which we interpret as being related to the gabbro intrusion that hosts the mineralization. The large-wavelength structures in the S-wave velocity models are relatively consistent with the geological structures inferred from surface mapping and drill core data. These results show that the ANSWT, focused on the high-frequency signal provided by anthropogenic noise sources, is an efficient technique for imaging “shallow" (1 km depth) geological structures in a mineral exploration context. </p>


2021 ◽  
Vol 502 (4) ◽  
pp. 5612-5621
Author(s):  
Pol Gurri ◽  
Edward N Taylor ◽  
Christopher J Fluke

ABSTRACT We analyse the first measurements from precision weak lensing (PWL): a new methodology for measuring individual galaxy–galaxy weak lensing through velocity information. Our goal is to understand the observed shear distribution from PWL, which is broader than can be explained by the statistical measurement errors. We identify two possible sources of scatter to explain the observed distribution: a shape noise term associated with the underlying assumption of circular stable rotation, and an astrophysical signal consistent with a lognormal dispersion around the stellar-to-halo mass relation (SHMR). We have modelled the observed distribution as the combination of these two factors and quantified their most likely values given our data. For the current sample, we measure an effective shape noise of σγ = 0.024 ± 0.007, highlighting the low noise impact of the method and positioning PWL as ∼10 times more precise than conventional weak lensing. We also measure an average dispersion in shears of $\xi _\gamma = 0.53^{+0.26}_{-0.28}$ dex over the range of 8.5 < log M⋆ < 11. This measurement is higher than expected, which is suggestive of a relatively high dispersion in halo mass and/or profile.


2019 ◽  
Vol 10 (1) ◽  
pp. 46 ◽  
Author(s):  
Huanhuan Liu ◽  
Zilong Li ◽  
Wei Song ◽  
Ye Yu ◽  
Fufei Pang ◽  
...  

2019 ◽  
Vol 9 (16) ◽  
pp. 3366 ◽  
Author(s):  
Chao Wang ◽  
Yajing Zhang ◽  
Zheng Wu ◽  
Guoxu Zhang ◽  
Yiyang Zhang ◽  
...  

In this paper, the all-solid dual-concentric-core microstructure fiber (MSF) with ultra-broadband dispersion compensation characteristics is designed. The effects of microstructure fiber structure parameters on dispersion, phase-matching wavelength, and kappa value are analyzed by the multi-pole method and mode coupling theory. The average dispersion compensation multiple is 18.45, that is, 1 km long dispersion compensated MSF can compensate for the cumulative dispersion of standard single-mode fiber of 18.45 km in the wavelength range of 1385~1575 nm by optimizing MSF parameters. The change range of residual dispersion is within ±0.72 ps/(nm·km), and the splicing loss with standard single-mode fiber is controlled below 5 dB within the compensation bandwidth of 190 nm. Compared with the air hole-quartz structure dual-concentric-core microstructure fiber, the designed fiber reduces the difficulty of fiber drawing, is easy to splice with standard single-mode fiber, and has wider compensation bandwidth as well as larger compensation multiple than the existing microstructure fiber. This lays a solid foundation for the optimization of dense wavelength division multiplexing networks and the construction of all-optical networks.


2019 ◽  
Vol 13 (1) ◽  
pp. 11-20 ◽  
Author(s):  
Zsuzsanna Bacsi ◽  
Zsolt Hollósy

A good crop production technology should provide high yields under varying environmental conditions, i.e. keep yield fluctuations small. The magnitude of fluctuations is usually measured by statistical indicators of average dispersion, e.g. the standard deviation. However, while many small fluctuations are usually well tolerated by the farmer, an extreme yield may be a serious risk factor.  The present research introduces a yield stability index developed which measures the frequency of extremely high and extremely low yields. The index is tested for 10 countries and 18 crops for 2004-2016, comparing it to 1961-2000, pointing out possible agricultural policy implications.


2016 ◽  
Vol 6 ◽  
pp. 3-10
Author(s):  
Kyrylo Samoichuk ◽  
Sergey Kiurchev ◽  
Vadym Oleksiienko ◽  
Nadiya Palyanichka ◽  
Valentina Verholantseva

The modification of rotor-pulsation machine – pulsation machine with a vibrating rotor (PM with VR) has been researched in the work. Rotor in such modification not only rotates but also oscillates axially with the frequency about 3000 min-1 and amplitude 0,5–1,0 mm. The aim of this research was to define specific features of milk homogenization process in PM with VR and disperse characteristics of milk emulsion. Analytical researches resulted in finding dependence of milk emulsion acceleration as a main factor of milk fat particles breakup subject to the design and kinematic parameters of PM with VR. Experimental researches were carried out on the laboratory setup of the pulsation machine with a vibrating rotor which was designed by the authors. The subject of experimental researches is cow's milk. The sizes of milk fat globules after homogenization were measured by the optical microscope equipped with a digital camera. The researches resulted in defining characteristics of milk emulsion dispersing in PM with VR. Thus acceleration grows when diameter, oscillation amplitude and rotation frequency of the rotor are increased, and channels length of the rotor and stator, the gap between them are decreased and the number of rotor openings is 4 or less. Empirical dependence between the average diameter of the fat globule (0,7–1,9 μm) and the average emulsion acceleration ((1–10)·103 m/s2) in the interrupter of PM with VR is defined which proves that the emulsion flow acceleration is the main cause of homogenization of PM with VR with 92 % confidence. High quality of the milk emulsion after processing in PM with VR has been proved. The crankshaft rotation frequencies up to 2880 rpm and rotor oscillation amplitude of 1 mm enable to receive milk emulsion with the average dispersion about 0,8 μm that corroborates using PM with VR in the industrial conditions for milk homogenization to be perspective.


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