Measurements of the unsteady flow field within the stator row of a transonic axial-flow fan. 1: Measurement and analysis technique

This two-part paper presents laser anemometer measurements of the unsteady velocity field within the stator row of a transonic axial-flow fan. The objective is to provide additional insight into unsteady blade-row interactions within high speed compressors which affect stage efficiency, energy transfer, and other design considerations. Part 1 describes the measurement and analysis techniques used for resolving the unsteady flow field features. The ensemble-average and variance of the measured velocities are used to identify the rotor wake generated and unresolved unsteadiness, respectively. (Rotor wake generated unsteadiness refers to the unsteadiness generated by the rotor wake velocity deficit and the term unresolved unsteadiness refers to all remaining contributions to unsteadiness such as vortex shedding, turbulence, mass flow fluctuations, etc.). A procedure for calculating auto and cross correlations of the rotor wake generated and unresolved unsteady velocity fluctuations is described. These unsteady-velocity correlations have significance since they also result from a decomposition of the Navier-Stokes equations. This decomposition of the Navier-Stokes equations resulting in the velocity correlations used to describe the unsteady velocity field will also be outlined in this paper

5-Fluoro-1,3-dihydro-2,1-benzoxaborol-1-ol

In the crystal structure of the title compound, C7H6BFO2, a broad-spectrum anti­fungal drug (AN2690), the planar [maximum deviation 0.035 (1) Å] mol­ecules form centrosymmetric R 2 2(8) dimers via strong O—H⋯O hydrogen bonds. The dimers are arranged into layers by weak inter­molecular C—H⋯O and C—H⋯F hydrogen bonds. The symmetry of this two-dimensional supra­molecular assembly can be described by the layer group p and topologically classified as a simple uninodal four-connected two-dimensional network of a (4.4.4.4.6.6) topology. Further weak C—H⋯O inter­actions build up the three-dimensional structure

The impact of health on professionally active people's incomes in Poland. Microeconometric analysis

The outcome of the research confirms the occurrence of positive interaction between professionally active people's incomes and the self-assessed state of health. People declaring a bad state of health have incomes by 20% on average lower than people who enjoy good health (assuming that the remaining characteristics of the surveyed person are the same). In case of men, the impact of health state on incomes is slightly greater than in case of women.Wyniki badań potwierdzają istnienie pozytywnej zależności dochodów osób aktywnych zawodowo od stanu zdrowia mierzonego jego samooceną. Osoby deklarujące zły stan zdrowia osiągają dochody przeciętnie o 20% niższe niż osoby, które cieszą się dobrym stanem zdrowia (przy założeniu, że pozostałe charakterystyki badanej osoby są takie same). W przypadku mężczyzn zależność dochodów od stanu zdrowia jest nieznacznie silniejsza niż w przypadku kobiet

Visual Outcomes of Pupilloplasty in Ocular Trauma and Iatrogenic Damage

Purpose: To report the visual outcomes of different techniques for iris pupilloplasty in eyes after traumatic and iatrogenic damage. Methods: 70 consecutive eyes with posttraumatic (80%) and postoperative (20%) iris damage were included. According to the preoperative diagnosis, the eyes were divided into three groups: mydriasis (50%), partial iris defects (24%), and iridodialysis (26%). Multiple techniques were performed: the Siepser slip-knot technique, the “lasso” technique, and suturing to the sclera. These techniques were combined in some cases. Results: The best improvement of visual acuity was found for the Siepser slip-knot technique with a median of 0.7 (SD ± 0.83) before surgery and 0.52 logMAR (SD ± 0.65) after surgery with regard to the surgical technique, and for mydriasis with a median of 0.7 (SD ± 0.75) before surgery and 0.52 logMAR (SD ± 0.49) after surgery with regard to preoperative diagnosis. Pupilloplasty was combined with additional surgery (corneal suturing, secondary intraocular lens implantation, anterior or pars plana vitrectomy) in 80% of cases. Apart from corneal suturing, all additional procedures ensured improvement in visual acuity. Conclusions: The slip-knot technique was the only suturing technique that resulted in a significant improvement in visual acuity. Other surgical procedures are usually needed in the majority of cases that undergo pupilloplasty, and they also give visual gain

Inclusive Charged Hadron Elliptic Flow in Au + Au Collisions at √ˢᴺᴺ = 7.7-39 GeV

A systematic study is presented for centrality, transverse momentum pT, and pseudorapidity (η) dependence of the inclusive charged hadron elliptic flow v2 at midrapidity (|η| \u3c 1.0) in Au + Au collisions at √ˢᴺᴺ = 7.7, 11.5, 19.6, 27, and 39 GeV. The results obtained with different methods, including correlations with the event plane reconstructed in a region separated by a large pseudorapidity gap and four-particle cumulants (v2{4}), are presented to investigate nonflow correlations and v2 fluctuations. We observe that the difference between v2{2} and v2{4} is smaller at the lower collision energies. Values of v2, scaled by the initial coordinate space eccentricity, v2/ϵ, as a function of pT are larger in more central collisions, suggesting stronger collective flow develops in more central collisions, similar to the results at higher collision energies. These results are compared to measurements at higher energies at the Relativistic Heavy Ion Collider √ˢᴺᴺ = 62.4 and 200 GeV) and at the Large Hadron Collider (Pb + Pb collisions at √ˢᴺᴺ = 2.76 TeV). The v2(pT) values for fixed pT rise with increasing collision energy within the pT range studied (\u3c2 GeV/c). A comparison to viscous hydrodynamic simulations is made to potentially help understand the energy dependence of v2(pT). We also compare the v2 results to UrQMD and AMPT transport model calculations, and physics implications on the dominance of partonic versus hadronic phases in the system created at beam energy scan energies are discussed