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121.
We have developed an ABCD matrix that, for the first time to our knowledge, accurately describes the transformation of a Gaussian beam by a medium with transversely varying saturable gain. In contrast with the conventional ABCD matrix, the newly developed matrix is shown to be in excellent agreement with a full beam propagation code over a wide parameter range. Accurate treatment of transversely varying saturable gain in laser resonators is important for the optimization of end-pumped lasers, particularly for efficient diode-pumped solid-state and Kerr-lens mode-locked systems. 相似文献
122.
Rebecca A.H. Butler Paul Helminger Ewa Bialkowska-Jaworska 《Journal of Molecular Spectroscopy》2007,244(2):113-116
The pure rotational spectrum of chlorine nitrate in its v6 = 1 excited vibrational state has been studied. A total of 2901 lines, with Ka extending to 33 in the 35Cl isotopologue and 30 in the 37Cl isotopologue, respectively, have been recorded and assigned. This analysis, along with our recently reported study of the ν5/ν6ν9 dyad and the improved energy levels of ν9 reported in this paper, should make possible accurate simulation of the corresponding ν6 band and its complex hot band structure near 435 cm−1. 相似文献
123.
PROCEDURAL CONSIDERATIONS FOR ROAD SIMULATION 总被引:5,自引:0,他引:5
M. French 《Experimental Techniques》2000,24(6):46-47
124.
Chassis dynamometers are a valuable tool for evaluating the performance of full vehicles. The basic concept is flexible enough that a very wide range of
wheeled vehcles can be tested. They are routinely used to evaluate drive train performance, full vehicle noise and vibration characteristics and other ve-
hicle parameters. Of course, their use is limited to situations in which complete, running vehicles are available. For situations in which that is not true, four poster and shaker tables can be used. These systems are described in the next article in this series. 相似文献
wheeled vehcles can be tested. They are routinely used to evaluate drive train performance, full vehicle noise and vibration characteristics and other ve-
hicle parameters. Of course, their use is limited to situations in which complete, running vehicles are available. For situations in which that is not true, four poster and shaker tables can be used. These systems are described in the next article in this series. 相似文献
125.
126.
AN INTRODUCTION TO ROAD SIMULATION TESTING 总被引:5,自引:0,他引:5
M. French 《Experimental Techniques》2000,24(3):37-38
127.
Experimental Techniques - 相似文献
128.
Amanda D. French Hannah M. Ashbaugh Gary Steinmetz Melanie Barnes Warren C. Conway David M. Klein 《International journal of environmental analytical chemistry》2017,97(6):499-507
The S.M.A.R.T. (small mass, affordable, rapid, transfer-less) digestion method was developed to determine heavy metal concentrations in small sample masses. The S.M.A.R.T. digestion method is a hot water bath digestion where sample digestion and dilution are performed in the original sample tube. This method is faster than the typical methods used and reduces potential sources of error. Masses as small as 0.01 g have been digested and analysed using this method. The preparation and digestion time is reduced from 10 h to less than 4 h. Acid volumes are reduced from millilitres to microlitres and the only disposable supplies needed are sample tubes and pipette tips. Method accuracy was determined by digesting seven replicates of two standard reference materials using the S.M.A.R.T. method and analysing samples by inductively coupled plasma mass spectrometry. The S.M.A.R.T. digestion method was found to provide excellent recoveries for Al (76 ± 2.7%), Mn (99 ± 11%), Co (92 ± 17%), Ni (93 ± 28%), Cu (109 ± 33%), Zn (97 ± 7.1%), As (108 ± 20%), Sr (90 ± 12%), Mo (84 ± 23%), Ag (91 ± 1.8%), Cd (95 ± 6.2%), Sn (139 ± 52%) and Pb (95 ± 22%). This study has successfully developed an efficient and reproducible digestion method for heavy metal determination in limited biomass samples. 相似文献
129.
Andrew N. Cammidge Rebecca J. Turner Rhoda D. Beskeni Tahani Almutairi 《Liquid crystals》2017,44(12-13):2018-2028
ABSTRACTWe report the unexpected observation of columnar mesophase formation in a simple 2,7-dibromotetramethoxytriphenylene – by far the most lightly substituted discotic mesogen in this class. This derivative was prepared alongside the 3,6-dibromotriphenylene isomer to demonstrate an alternative, modified synthetic strategy that permits late-stage interchange of alkyl chain substituents. The new method is employed alongside the original route to deliver several new materials, including a conjugated ferrocene–triphenylene–ferrocene triad, a BODIPY–triphenylene–BODIPY triad and a new nematic twin linked through imine bridges. 相似文献
130.
Expeditious routes to 1,2,3,4,4a,5-hexahydro-pyrazino[2,1-c][1,4]benzothiazine-6,6-dioxide, a methylenesulfone-constrained arylpiperazine, have been developed. The key step forms the tricyclic system in a cascade of reactions via a 1,4-addition, nitrogen alkylation, and aromatic substitution sequence. 相似文献