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101.
It has been asserted in the literature that a particular solution of the Liouville equation, ?xtσ = eσ, can be interpreted as an N-soliton. It is shown here that this solution id in fact familiar one-soliton written in a misleading form. 相似文献
102.
The spectrum of the light emitted during thermoluminescence from irradiated LiF(Mg,Cu,P) has been measured for samples with different Cu and P contents. The results show no essential differences in glow curve structure and emission spectrum for MCP materials with different dopant contents and produced with different production techniques, except for samples with a low phosphorus concentration. The emission spectrum consits of two bands with maxima at 350 and 384 nm; the latter is dominant in the main glow peak and the former becomes more important at higher temperatures. Both bands are correlated with phosphorus, which appears to play a vital role in the overall sensitivity. 相似文献
103.
Trifluoroacetonitrile was condensed with diethyl malonate to give a novel ethyl 2,6-bis(trifluoromethyl)-4-hydroxypyrimidine-5-carboxylate ( 2 ) in 88% yield. Derivations of 2 are also described. 相似文献
104.
105.
106.
Araujo K Colina M Mazurek R Delgado J Ledo H Gutierrez E Herrera L 《Analytical and bioanalytical chemistry》1996,355(3-4):319-320
The mercury concentrations in wastewater and sewage sludge of a stabilization pond system have been evaluated. The system is built by three parallel facultative ponds followed by two systems of three maturation ponds in series. The samples of wastewater and sludge were digested using nitric acid and placed into a Parr-type bomb for 4 h at 110 degrees C. Mercury was measured by Cold Vapour Atomic Absorption Spectrometry (CV-AAS) at 253.7 nm with sodium tetrahydroborate as reductant. The methodologies were checked with an USEPA quality control sample, a standard reference material from NIST and with another method of mineralization (cold mineralization) showing good results. Concentrations of mercury in wastewater between 1.47 +/- 0.75 microgl(-1) have been found at the entrance of the system and 0.74 +/- 0.0 microgl(-1) at the exit, while in sludge the results were between 0.29 +/- 0.12 microgkg(-1) in the facultative pond and 0.04 +/- 0.02 microgkg(-1) in the second maturation pond (exit). 相似文献
107.
Deposition to glass of Streptococcus salivarius HB-C12 and Staphylococcus epidermidis 3399 in a parallel plate flow chamber in the absence and presence of an externally applied electric field has been studied experimentally. No effect on bacterial adhesion, including initial deposition rates, numbers of adhering bacteria after 4 h, spatial distributions of adhering bacteria and air bubble induced detachment, was found. A theoretical analysis shows that electric fields applied over a 150 μm thin glass substratum do not have a sufficiently strong effect on its surface potential to influence bacterial adhesion. 相似文献
108.
Neural network software is described for processing the signals of arrays of ion-selective electrodes. The performance of the software was tested in the simultaneous determination of calcium and copper(II) ions in binary mixtures of copper(II) nitrate and calcium chloride and the simultaneous determination of potassium, calcium, nitrate and chloride in mixtures of potassium and calcium chlorides and ammonium nitrate. The measurements for the Ca2+/Cu2+ determinations were done with a pH-glass electrode and calcium and copper ion-selective electrodes; results were accurate to ±8%. For the K+/Ca2+NO?3/Cl? determinations, the measurements were made with the relevant ion-selective electrodes and a glass electrode; the mean relative error was ±6%, and for the worst cases the error did not exceed 20%. 相似文献
109.
The use of pulse techniques and current sampling available at the dropping mercury electrode (DME) is described for polarographic flow-through detectors. The necessary synchronization between the drop lifetime and the desired measuring technique is achieved by means of a potential pulse supplied to a horizontal DME with a partially-conical glass capillary. 相似文献
110.
Katrin de Graaf Hanna Czajkowska Sabine Rottmann Len C Packman Richard Lilischkis Bernhard Lüscher Walter Becker 《BMC biochemistry》2006,7(1):7