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1.
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An improved version of the four-hole directional pressure probe, or Cobra probe, is described, in which the frequency response has been extended to 1.5 kHz. The probe measures all three orthogonal mean and turbulent velocity components at a point in the flow field. The probe also resolves the local mean and turbulent components of static pressure, allowing moments between the fluctuating velocity components and pressure to be determined. The techniques developed to allow the improved frequency response and the use of the probe in turbulent, developed pipe flow (a calibration flow) are described. Also given are the turbulent pressure-velocity correlations, which show a high degree of anticorrelation for one velocity component. 相似文献
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G. M. Schneider J. D. Hooper A. R. Musgrove G. J. Nathan R. E. Luxton 《Experiments in fluids》1997,22(6):489-495
A novel fluid mixing device, described elsewhere, has been shown to have a dramatic effect on the combustion characteristics
of a fuel jet. The main features of the flow are the deflection of the jet between 30° and 60° from the nozzle axis and its
precession about that axis. Many of the factors governing the nozzle instabilities which drive the mixing in the external
field are imprecisely defined. It is the aim of the present paper to examine, in isolation from the nozzle instabilities,
the influence of precession on a deflected jet as it proceeds downstream from the nozzle exit. The fluid dynamically driven
phenomena within the nozzle which cause the precession are in the present investigation replaced by a mechanical rotation
of a nozzle from which is emerging a jet which is orientated at an angle from the nozzle axis. By this means the effect of
precession on the deflected jet can be investigated independently of the phenomena which cause the precession.
The experimental data reported here has been obtained from measurements made using a miniature, rapid response four-hole “Cobra”
pitot probe in the field of the precessing jet. Phase-averaged three dimensional velocity components identify the large scale
motions and overall flow patterns. The measured Reynolds stresses complement the velocity data and are found to be compatible
with the higher entrainment rates of the jet found in earlier investigations.
Received: 8 November 1995 / Accepted: 27 September 1996 相似文献
5.
The paper reports the results of experimental measurements of the reflection pressures close to spherical charges of TNT. These measurements were made using a pressure bar technique. Charge weights of up to 3.6 kg were used, with the reflecting plane in the range 25 to 300 mm from the charge surface.A possible wave interaction model is discussed, to account for the observed pressure profiles, and its qualitative correctness checked by means of numerical simulation.This article was processed using Springer-Verlag TEX Shock Waves macro package 1.0 and the AMS fonts, developed by the American Mathematical Society. 相似文献
6.
Bimetallic Gold(I) Complexes with Ethynyl‐Helicene and Bis‐Phosphole Ligands: Understanding the Role of Aurophilic Interactions in their Chiroptical Properties 下载免费PDF全文
Dr. Mehdi El Sayed Moussa Dr. Hui Chen Zuoyong Wang Dr. Monika Srebro‐Hooper Dr. Nicolas Vanthuyne Dr. Soizic Chevance Prof. Christian Roussel Prof. J. A. Gareth Williams Prof. Jochen Autschbach Prof. Régis Réau Prof. Zheng Duan Dr. Christophe Lescop Dr. Jeanne Crassous 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(17):6075-6086
Monometallic gold(I)‐alkynyl‐helicene complexes ( 1 a , b ) and bimetallic gold(I)‐alkynyl‐helicene architectures featuring the presence ( 2 a , b ) or absence ( 3 a , b ) of aurophilic intramolecular interactions were prepared by using different types of phosphole ligands (mono‐phosphole L1 or bis‐phospholes L2 , 3 ). The influence of the AuI d10 metal center(s) on the electronic, photophysical, and chiroptical properties of these unprecedented phosphole‐gold(I)‐alkynyl‐helicene complexes was examined. Experimental and theoretical results highlight the importance of ligand‐to‐ligand‐type charge transfers and the strong effect of the presence or absence of AuI–AuI interactions in 2 a , b . 相似文献
7.
Back Cover: Large‐Scale Synthesis of Helicene‐Like Molecules for the Design of Enantiopure Thin Films with Strong Chiroptical Activity (Chem. Eur. J. 10/2016) 下载免费PDF全文
8.
Large‐Scale Synthesis of Helicene‐Like Molecules for the Design of Enantiopure Thin Films with Strong Chiroptical Activity 下载免费PDF全文
Dr. Amina Bensalah‐Ledoux Delphine Pitrat Thibault Reynaldo Dr. Monika Srebro‐Hooper Barry Moore II Prof. Jochen Autschbach Dr. Jeanne Crassous Prof. Stéphan Guy Dr. Laure Guy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(10):3333-3346
Helicenes are fascinating molecules owing to their unusual properties and applications in many fields from catalysis to organic electronics. Herein, we report a straightforward pathway for the synthesis of helicene‐like molecules on a gram scale in an enantiopure form. Thin‐film materials with good propagating optical properties and very high chiroptical responses have been grown by using pulsed laser ablation without altering the structure or the enantiopurity of the molecules. Moreover, electronic and vibrational circular dichroism spectroscopies coupled with theoretical calculations enabled some dependences of the chiroptical properties with the structure to be highlighted, for example, effects of rigidification, aromatization, or the state of matter (liquid versus solid). 相似文献
9.
Frontispiece: NMR Fingerprints of the Drug‐like Natural‐Product Space Identify Iotrochotazine A: A Chemical Probe to Study Parkinson’s Disease 下载免费PDF全文