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911.
Dilip H. Dagade Rajendra R. KumbharSandip R. Sabale Kesharsingh J. Patil 《Fluid Phase Equilibria》2007
In the present communication, we report the studies concerning liquid–liquid–solid equilibria for the ternary system sodium thiosulphate (Na2S2O3) + ethanol + water at ambient pressure and at room temperature (303 ± 2 K). The solubility data of Na2S2O3 are reported for solutions in water, ethanol and solutions of varying concentrations of ethanol in water. The phase diagram for the said system is developed, described and compared with similar system K2CO3 + methanol + water. These results have been explained in terms of structural properties of aqueous ethanol solutions and further discussed in terms of the effect of ions to cause phase separation. 相似文献
912.
H. A. Levine R. Quintanilla L. E. Payne 《Mathematical Methods in the Applied Sciences》1989,11(1):71-77
We consider a three-dimensional hyperelastic cylinder in Ω = D × [0, ∞]. We study the asymptotic behaviour of the deformations of the cross-sections in an equilibrium state. In this case we show that the solutions either have exponential decay or exponential growth. We give some initial conditions such that the latter case occurs. 相似文献
913.
It has been described earlier that imaging measurements of laser-induced fluorescence (LIF) in flames can be calibrated to number densities with an integrated absorption measurement provided the integrated absorption is small. In this paper a method is presented that extends the technique to flames with substantial absorption, improves the number density determination and allows the experimental parameters to be chosen more freely. The method is based on an iterative computer procedure that reconstructs the 1-D spatially resolved absorption profile from laser measurements of the 1-D spatially resolved LIF and the integrated absorption of the laser beam. The technique is experimentally demonstrated by measurements of OH number densities in atmospheric flames. It is potentially a single-pulse method. Other applications of the iterative procedure are mentioned. 相似文献
914.
Applications and trends of nonequilibrium plasma chemistry with organic and organometallic compounds
The possibilities and limitations of available apparatus for nonequilibrium discharges are discussed. Especially for synthetic work there is a lack of suitable equipment. The unique possibilities which plasmas offer to chemistry are demonstrated by examples from the homogeneous gas phase, and from plasma liquid and plasma solid interactions. Various applications and major trends are being described. The most rapidly increasing field of plasma chemistry is presently the formation of thin films of metals, oxides, carbides, or nitrides by plasma enhanced CVD. The latest results, and especially the use of organometallic compounds and starting material, are being discussed. 相似文献
915.
916.
N Fujii T Watanabe A Otaka K Bessho I Yamamoto T Noda H Yajima 《Chemical & pharmaceutical bulletin》1987,35(12):4769-4776
917.
M.L.H. Gruwel P. Latta M. Tanasiewicz V. Volotovskyy M. Šramek B. Tomanek 《Applied Physics A: Materials Science & Processing》2007,88(4):763-767
Magnetic resonance imaging (MRI) of teeth is an emerging application area which is still in development. Previous investigations
did not fully focus on potential in vivo applications. Using 1H and 31P MRI, we obtained ex vivo microimages of teeth with a silent single point imaging (SPI) technique. 1H Images with an in-plane resolution of 310×310 μm2 were obtained. Utilizing sine-shaped gradient ramps significantly reduced the sound pressure level of the experiment to that
of background noise. 1H magnetic resonance spectroscopy (MRS) was used to characterize the major components in the observed resonance. The spin–spin
(T2) relaxation times of water in enamel and dentin differed by at least one order of magnitude. Three-dimensional surface reconstruction
of the data allowed for complete visualization of the tooth’s surface while volume reconstruction displayed the internal geometry.
PACS 82.56.Na; 83.85.Fg; 87.61.-c; 87.19.-j; 43.50.Cb 相似文献
918.
M.C. Robinson D.J. Morris P.D. Hayenga J.H. Cho C.D. Richards R.F. Richards D.F. Bahr 《Applied Physics A: Materials Science & Processing》2006,85(2):135-140
Piezoelectric membranes have been fabricated that incorporate a gold bottom electrode with an adhesion layer of titanium–tungsten (10:90 wt. %). For solution-deposited acetic acid based lead zirconate titanate (HoAc-PZT) with a Zr:Ti ratio of 40:60, the film’s average piezoelectric coefficient, e31, is -5.31 C/m2, with a dielectric constant of 814 at 200 Hz, which is similar to values for platinum bottom electrodes. The PZT structure remains columnar on both types of bottom electrodes. Initial fabrication attempts resulted in cracking that initiated in the PZT layer of the structure. X-ray photoelectron spectroscopy was utilized to establish how processing affects diffusion throughout the composite membrane structure. Crack-free membranes were fabricated and tested. This paper discusses the performance properties and piezoelectric fatigue results for these membranes. PACS 77.84.-s; 77.84.Lf 相似文献
919.
920.
S. Barth H. R. Ott F. N. Gygax B. Hitti E. Lippelt A. Schenck Z. Fisk 《Hyperfine Interactions》1989,50(1-4):709-716
μ+ SR-measurements in transversally applied magnetic fields of 2000 G and 4000 G on heavy-electron single crystal U2Zn17 are presented. They reveal that at least two types of interstitial sites are occupied by the positive muons. One of these
sites (1/3, 2/3, 5/6) could be identified via induced local dipolar fields which aboveT
N=9.7 K can exactly be derived from the magnetic susceptibility. The corresponding component of the μ+-signal exhibits a steplike decrease by about 40% atT
N which is caused by the onset of a very broad distribution of static internal magnetic fields (ΔB≈1000 G) with zero average. Such a field distribution is in distinct contrast to dipolar-field calculations performed for
the simple antiferromagnetic structure deduced from neutron diffraction. The remaining 60% of the muons contributing to this
component belowT
N are subject to a narrow static field distribution (ΔB≈1 G). The induced dipolar fields at the site (1/3, 2/3, 5/6) are temperature-independent belowT
N. A weak dipolar coupling to the U-moments renders similar observations for muons occupying the second type of interstitial
impossible. 相似文献