6,852 research outputs found
Magnetic Field Uniformity Across the GF 9-2 YSO, L1082C Dense Core, and GF 9 Filamentary Dark Cloud
The orientation of the magnetic field (B-field) in the filamentary dark cloud
GF 9 was traced from the periphery of the cloud into the L1082C dense core that
contains the low-mass, low-luminosity Class 0 young stellar object (YSO) GF 9-2
(IRAS 20503+6006). This was done using SOFIA HAWC+ dust thermal emission
polarimetry (TEP) at 216 um in combination with Mimir near-infrared background
starlight polarimetry (BSP) conducted at H-band (1.6 um) and K-band (2.2 um).
These observations were augmented with published I-band (0.77 um) BSP and
Planck 850 um TEP to probe B-field orientations with offset from the YSO in a
range spanning 6000 AU to 3 pc. No strong B-field orientation change with
offset was found, indicating remarkable uniformity of the B-field from the
cloud edge to the YSO environs. This finding disagrees with weak-field models
of cloud core and YSO formation. The continuity of inferred B-field
orientations for both TEP and BSP probes is strong evidence that both are
sampling a common B-field that uniformly threads the cloud, core, and YSO
region. Bayesian analysis of Gaia DR2 stars matched to the Mimir BSP stars
finds a distance to GF 9 of 270 +/- 10 pc. No strong wavelength dependence of
B-field orientation angle was found, contrary to previous claims.Comment: 18 pages, 6 figures ApJ, accepte
Value pricing in the chemical industry:most powerful lever to profitability
The chemical industry in Europe is working hard on the improvement of their profitability base. But while innovation and complexity management are heavily discussed by the industry’s top managers, the most powerful lever to increase profitability is being ignored by many – value pricing. Arthur D. Little, jointly with Warwick Business School, conducted a pricing survey with the participation of managers from all chemical industry segments in which measures for profitability increases were investigated. Although a price increase of 1 % can lever the profit (EBIT) by 8 %, many companies focus on much weaker levers like reducing variable costs and sales volumes. In this article we look into the possible benefits of value pricing, the effective BASF approach and the problems posed by a customer management focussing on the perceived strategic importance of customers rather than their contribution margins
Concentration of Chlorophyll-a as the Determinant of Trophic Status in the Samsam Swamp, Kandis Sub District, Siak District, Riau Province
Samsam Swamp is a lowland swamp that receives water from the Samsam River during the rainy season. To understand the trophic status of Samsam Swamp, a present study based on the concentration of chlorophyll-a was conducted in March-April 2016. The method used was a survey method. There were four sampling stations namely Station 1, Station 2, Station 3 and Stasion 4. Samplings were conducted 3 times, once a week. Results shown that concentration of chlorophyll-a was 4.05 – 7.69 μg/L; temperature 28 – 33⁰ C, transparency 28 – 46.9 cm, water pH 4 – 5, orthophosphate 0.37 – 0.65 mg/L, nitrate 0.33 – 0.63 mg/L, dissolved oxygen 3.69 – 4.93 mg/L, free carbon dioxide 4.00 – 11.99 mg/L and depth 39 – 170 cm. Based on the concentration of chlorophyll-a, Rawa Samsam is classified as mesotrophic waters
The Vertical Profiles of Phytoplankton in Danau Pinang Luar Buluh CinaVillage, Siak Hulu Sub- District, District Kampar, Riau Province
This research was conducted on the Danau Pinang Luar Buluh Cina Village Siak HuluSubdistrict District Kampar Riau Province in April - Mei 2013 and aims to understand thephytoplankton vertical rofil in the Pinang Luar Lake. There were 3 stations, station 1 isincomingwater area, Station 2 is agencies lake area. Station 3 is end of the lake area. Samplings wereconducted 3 times, once/week.This research aims to determine the vertical profile ofphytoplankton of Danau Pinang Luar.The results showed 24 species of phytoplankton were classified into four classes, namely:Chlorophyceae (11 species), Cyanophyceae (7 species),Bacillariophyceae (5 species), Euglenophyceae (1 species). Average phytoplankton abundancearound 61578 - 495112 cells/l, species diversity index (H ') of phytoplankton around 4,21 - 4,51,uniformity index around 0,87 - 0,93 and dominance index (C) of about 0,046- 0,063. While thewater quality parameters such as temperature of 31°C, the brightness around 65 - 70 cm, a depth ofapproximately 261,7 - 461.7 cm, pH 6, Dissolved Oxygen approximately 2,93 – 6,4 mg/l, free ofcarbon dioxide around 3,96 – 11,88 mg/l, Nitrate around 0,01-0,02 mg/l, Phosphate approximately0,023 mg/l. Based on the abundance of phytoplankton, concluded that Danau Pinang Luar Outerrelatively moderate fertility levels
The Herschel Virgo Cluster Survey XVI: a cluster inventory
Herschel FIR observations are used to construct Virgo cluster galaxy
luminosity functions and to show that the cluster lacks the very bright and the
numerous faint sources detected in field galaxy surveys. The far-infrared SEDs
are fitted to obtain dust masses and temperatures and the dust mass function.
The cluster is over dense in dust by about a factor of 100 compared to the
field. The same emissivity (beta) temperature relation applies for different
galaxies as that found for different regions of M31. We use optical and HI data
to show that Virgo is over dense in stars and atomic gas by about a factor of
100 and 20 respectively. Metallicity values are used to measure the mass of
metals in the gas phase. The mean metallicity is about 0.7 solar and 50% of the
metals are in the dust. For the cluster as a whole the mass density of stars in
galaxies is 8 times that of the gas and the gas mass density is 130 times that
of the metals. We use our data to consider the chemical evolution of the
individual galaxies, inferring that the measured variations in effective yield
are due to galaxies having different ages, being affected to varying degrees by
gas loss. Four galaxy scaling relations are considered: mass-metallicity,
mass-velocity, mass-star formation rate and mass-radius - we suggest that
initial galaxy mass is the prime driver of a galaxy's ultimate destiny.
Finally, we use X-ray observations and galaxy dynamics to assess the dark and
baryonic matter content compared to the cosmological model
The Vertical Profile of Nitrate in the Lacustrine and Transition Zone Koto Panjang Reservoir Kampar District Riau Province
This research was carried out in the lacustrine and transition zone of Koto Panjang Reservoir from October - December 2013. Objective of the present research was to find out the vertical profile of nitrate in this reservoir. The research used survey method, samples were taken horizontally in four stations and vertically in five sampling points. The parameters of water quality measured were nitrate, dissolved oxygen (DO), pH, transparancy, temperature and depth. In the lacustrine zone concentration of nitrate in the surface was 0,148 – 0,166 mg/l, in the 2 Secchi depth was 0,16 – 0,168 mg/l, in the 4 Secchi depth was 0,153 – 0,162 mg/l, in the 12 m depth was 0,158 – 0,166 mg/l and in the bottom was 0,17 – 0,192 mg/l. In the transition zone concentration of nitrate in the surface was 0,1525 – 0,155 mg/l, in the 2 Secchi depth was 0,157 – 0,158 mg/l, in the 4 Secchi depth was 0,158 – 0,175mg/l, and in the bottom was 0,176 – 0,185mg/l. The concentration of dissolved oxygen (DO) was in the range of 0,10 – 8,75 mg/l. The value of pH was in the range of 5,4 – 5,9. Transparancy was in the range of 83,8 – 105 cm. Temperature was in the range of 28 – 32,3 oC. Depth was in the range of 9,3 – 22,7 m. The vertical profile of nitrate in the lacustrine and transition zone Koto Panjang reservoir of the present reseach revealed that nitrate concentration in the transition zone was relatively lower than that of lacustrine in the surface layer of the water, but the pattern of vertical nitrate profile in each zone was similar in which it increased with increasing depth. The parameters of water quality were observed still sustained the aquatic organism life
Development of Naphthalene PLIF for Visualizing Ablation Products From a Space Capsule Heat Shield
The Orion Multi-Purpose Crew Vehicle (MPCV) will use an ablative heat shield. To better design this heat shield and others that will undergo planetary entry, an improved understanding of the ablation process would be beneficial. Here, a technique developed at The University of Texas at Austin that uses planar laser-induced fluorescence (PLIF) of a low-temperature sublimating ablator (naphthalene) to enable visualization of the ablation products in a hypersonic flow is applied. Although high-temperature ablation is difficult and expensive to recreate in a laboratory environment, low-temperature sublimation creates a limited physics problem that can be used to explore ablation-product transport in a hypersonic flow-field. In the current work, a subscale capsule reentry vehicle model with a solid naphthalene heat shield has been tested in a Mach 5 wind tunnel. The PLIF technique provides images of the spatial distribution of sublimated naphthalene in the heat-shield boundary layer, separated shear layer, and backshell recirculation region. Visualizations of the capsule shear layer using both naphthalene PLIF and Schlieren imaging compared favorably. PLIF images have shown high concentrations of naphthalene in the capsule separated flow region, intermittent turbulent structures on the heat shield surface, and interesting details of the capsule shear layer structure. It was shown that, in general, the capsule shear layer appears to be more unsteady at lower angels of attack. The PLIF images demonstrated that during a wind tunnel run, as the model heated up, the rate of naphthalene ablation increased, since the PLIF signal increased steadily over the course of a run. Additionally, the shear layer became increasingly unsteady over the course of a wind tunnel run, likely because of increased surface roughness but also possibly because of the increased blowing. Regions with a relatively low concentration of naphthalene were also identified in the capsule backshell recirculation region and are most likely the result of cross-flow-induced vortices on the capsule afterbody
The Cartilage-Sparing Versus the Cartilage-Cutting Technique: A Retrospective Quality Control Comparison of the Francesconi and Converse Otoplasties
From a total of 281 patients with protruding ears who underwent a bilateral otoplasty between 1990 and 2001, a group of 28 (10%) was selected for a retrospective quality control study. The goal was to compare two methods of otoplasty, the Francesconi, a cartilage-sparing technique, and the Converse, a cartilage-cutting technique, in terms of objectively measurable and subjectively discernable differences in results. Objective parameters included measurement of the three cephaloauricular distances and the conchoscapal angle. An independent plastic surgeon performed the evaluation by means of a systematic evaluation system for rating cosmetic surgical procedures and a 5-point visual analog scale for rating satisfaction. The patients' subjective rate of satisfaction also was investigated using the 5-point scale. The mean medial and inferior cephaloauricular distances were significantly smaller in the Francesconi group. The concoscaphal angle was 90°, or less in all the patients of the Francesconi group, but more than 90° in eight patients (57%) of the Converse group (p = 0.041). Accordingly, the independent surgeon found adequate correction of protrusion in 86% of the Francesconi group and 50% of the Converse group (p = 0.050). His satisfaction rate was significantly in favor of the Francesconi technique (p = 0.006). Not unexpectedly, the patients' satisfaction rate was comparably high in both groups, and there was no statistical difference between them. In conclusion, the quality control led to a clear preference of the Francesconi over the Converse otoplasty. In addition, the assessment of the postoperative results with the systematic evaluation system offered an excellent information base by which to judge the results of otoplasty. Consequent use of this evaluation system will lead to progress in the surgical procedur
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