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971.
This paper provides an introduction to the workshop on methodologies for wastewater quality monitoring, Nimes, 29-30 October 1998, organised by the European Commission and Ecoles des Mines d'Alès. It highlights some overall aspects for the potential uses of on-line instrumentation related to wastewater management and focuses on relations to the urban wastewater treatment directive (91/271/EEC). Some potentials for further developments and actions related to the EU Directive are proposed. 相似文献
972.
Determination of berberine in Rhizoma coptidis and its preparations by non-aqueous capillary electrophoresis 总被引:1,自引:0,他引:1
A non-aqueous capillary electrophoretic method was established for the determination of berberine in Rhizoma coptidis and its preparations. The effects of organic solvent and the concentrations of sodium acetate were studied, which showed that berberine in extracts of traditional Chinese medicine can be separated successfully in a buffer solution of 75 mmol/L of sodium acetate in methanol containing 1 mol/L of acetic acid. The simple and rapid method was linear in the range 25-200 microgram/mL of berberine and had a good reproducibility, with the relative standard deviation below 2%. Non-aqueous capillary electrophoresis is a satisfactory system for the analysis of alkaloids in traditional Chinese medicine. 相似文献
973.
X. C. Zeng Y. Chen S. Q. Cheng X. G. Meng Q. Wang 《Journal of Thermal Analysis and Calorimetry》1999,58(2):477-485
A novel method for the determination of rate constants of reactions, the time-variable method, is proposed in this paper. The method needs only three time points (t), peak heights () and pre-peak areas (), obtained from the measured thermoanalytical curve. It does not require the thermokinetic reaction to be completed. It utilizes data-processing on a computer to give the rate constants. Four reaction systems, including a first-order reaction, second-order reactions (with equal concentrations and with unequal concentrations) and a third-order reaction, were studied with this method. The method was validated and its theoretical basis was verified by the experimental results.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
974.
考虑有独立调整时间的同型号平行机排序问题,极小化最迟完工时间,产品允许拆分,同一产品被拆分后各部分可以在不同机器上同时加工,该问题是NP-hard问题。本文首先给出该问题的一个启发式算法ML,然后证明了其最坏情况估计不超过7/4-1/m(m≥2)。 相似文献
975.
976.
Tian C Lu Q 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,59(6):7068-7073
The present paper shows that in one-dimensional collisionless plasma, due to large fluctuation, the time correlation of momentum asymptotically behaves inverse quadratically with time. The long-time tail correlation is closely related to nonlinear Landau damping [M.B. Isichenko, Phys. Rev. Lett. 78, 2369 (1997)]. Furthermore, it reveals the possible relationship between fluctuation and dispersion. The result indicates that the long-time tail correlation can also occur in a reversibly dispersive system, where the previous theories are invalid. A by-product proves that it may be efficient to investigate the dispersive features of collisionless plasma in view of time correlation. 相似文献
977.
0IntroductionPhenanthrolinederivativescontainingaminegroupshavebothsoftandhardsitesandaregooddonorsformetalions.1,10鄄phenanthrolineanditsderivativeshavebeenextensivelyusedasligandsinbothanalyticalandpreparativecoordinationchemis鄄try[1].Mostoftheseworksh… 相似文献
978.
979.
采用傅里叶变换光谱技术(FTS)记录了CH^35Cl3和它的同位素分子CH^35Cl2^37Cl的V=3的高分辨光谱,由于0.02m^-1分经不足以分辨K结构,我们将所观察到的谱线近似归属为K=0的转动能级,归属了CH^35Cl3岔子4〈J〈73,CH^35Cl^37Cl分子6〈J〈53的转动级。最后采用最小二乘法拟合,得到了关于J的转动常数和振动带心。 相似文献
980.
K. Andersen O. P. Anderson T. Miller N. S. Mani T. F. Baumann M. Anderson W. E. Broderick D. M. Eichhorn D. Goldberg W. Jarrell S. J. Lange S. Lee H. Nie M. Sabat J. W. Sibert C. Stern B. M. Hoffman S. Baum L. S. Beall A. S. Cook Q. J. Mccubbin A. Garrido Montalban M. S. Rodriguez-Morgade A. J. P. White D. B. G. Williams D. J. Williams A. G. M. Barrett H. Hope M. M. Olmstead 《Journal of heterocyclic chemistry》1998,35(5):1013-1042