EDXRF中复杂基体效应的一种校正方法研究

系统地介绍了一种用特征参数和相似分类法解决能量色散Ｘ射线荧光（ＥＤＸＲＦ）分析技术中复杂基体效应影响的方法，给出了应用事例。该方法可以推广到其它复杂类型的分析对象，具有较广泛的适用性。     

詹恩·丁伯根C-D生产函数的Eviews确定与经济评析

Eviews拥有统计分析、作图、数据处理、预测、模拟、建模分析(其中包括线性、非线性单一方程模型,向量自回归模型,误差修正模型,时间序列模型,动态回归模型,联立方程模型,分布滞后模型,离散选择模型以及多种估计方法)六大功能.对詹恩·丁伯根改进的C-D生产函数的Eviews确定进行了研究,并对其主要参数作偏导数分析基础上的经济评析.     

Potentiometric and Thermodynamic Studies of 2-Acrylamidosulfamethazine and Its Metal Complexes in Monomeric and Polymeric Forms

2-Acrylamidosulfamethazine (ASM) was synthesized and characterized by elemental analyses and IR spectroscopy. Proton-monomeric ligand dissociation and metal-monomeric ligand stability constants of ASM with some metal ions were determined potentiometrically in 0.1 M KCl and 40% (v/v) ethanol–water mixture. In the presence of 2,2-azobisisobutyronitrile as an initiator, the dissociation and stability constants of ASM were determined in polymeric form (PASM). The influence of temperature on the dissociation of ASM and the stability constants of their complexes in monomeric and polymeric forms were precisely studied. The pK^H value of PASM was found to be higher than ASM, which indicates that the vinyl group in the monomeric form decreases the electron density on nitrogen and hence reduces the N–H bond strength. The stability constants of the metal complexes in polymeric form are higher than those of the monomeric form. This reveals that the ligand in a polymeric form may be considered as a better complexing agent.     

Control of postharvest<Emphasis Type="Italic"> Rhizopus</Emphasis> rot of peach by microwave treatment and yeast antagonist

The potential of using microwave power alone, or in combination with antagonistic yeast, for control of Rhizopus stolonifer on peach, and its effects on the postharvest quality of peach were investigated. In in vitro tests, the growth of R. stolonifer was completely inhibited by a 2,450 MHz microwave heating for 2 min or more. The population density of R. stolonifer in surface wounds of microwave treatment fruits was significantly lower than that in the control. In vivo studies of inoculation of peach fruit with R. stolonifer followed by microwave treatment, Cryptococcus laurentii or both of them, microwave power and C. laurentii, as stand-alone treatments, were capable of reducing the percentage of decayed fruit from 95% in control, untreated fruit to 42.1% and 75%, respectively. However, in fruit treated with a combination of microwave power and C. laurentii, the percentage of decayed fruits was only 23.7%. The experiments on reducing natural decay development of fruit gave similar results. The microwave treatment, C. laurentii, or both of them did not impair the quality parameters of the fruit. Thus, the combination of microwave and C. laurentii could be an alternative to chemicals for control of postharvest Rhizopus rot on peach fruits.     

Determining Hydraulic Characteristics of Production Wells using Genetic Algorithm

Proper well management requires the determination of characteristic hydraulic parameters of production wells such as well loss coefficient (C) and aquifer loss coefficient (B), which are conventionally determined by the graphical analysis ofstep-drawdowntest data. However, in the present study, the efficacy of a non-conventional optimization technique called Genetic Algorithm (GA), which ensures near-optimal or optimal solutions, is assessedin determining well parameters from step-drawdown test data. Computer programs were developed to optimize the well parametersby GA technique for two cases: (i) optimization of B and C only, and (ii) optimization of B, C and p (exponent) as well as to evaluate the well condition. The reliability and robustness of the developed computer programs were tested usingnine sets of published and unpublished step-drawdown data from varying hydrogeologic conditions. The well parameters obtained by the GA technique were compared with those obtained by the conventional graphical method in terms of root mean square error(RMSE) and visual inspection. It was revealed that the GA technique yielded more reliable well parameters with significantlylow values of RMSE for almost all the datasets, especially in caseof three-variable optimization. The optimal values of the parametersB, C and p for the nine datasets were found to range from 0.382 to 2.292 min m^-2, 0.091 to 3.262, and 1.8 to 3.6, respectively. Because of a wide variation of p, the GA techniqueresulted in considerably different but dependable and robust well parameters as well as well specific capacity and well efficiency compared to the graphical method. The condition of three wells was found to be good, one well bad and that of the remaining five wells satisfactory. The performance evaluation of the developed GA code indicated that a proper selection of generation number and population size is essential to ensure efficient optimization. Furthermore,a sensitivity analysis of the obtained optimal parameters demonstrated that the GA technique resulted in a unique set ofthe parameters for all the nine datasets. It is concluded thatthe GA technique is an effective and reliable numerical tool for determining the characteristic hydraulic parameters of production wells.     

高压吸附下的瓦斯放散初速度研究

实验中将常压吸附改为高压吸附,并适当改变其它实验参数,利用抚顺分院在国家"十五"攻关中研制的仪器对煤样0～60s内的放散速度规律进行研究,计算其放散量、曲线变化率、放散初速度和衰减规律,进而提出更合理、更全面、物理意义更明确的突出预测指标。     

Optimization of weighting methods of smoothing the discreteness error of distance sensors based on a frequency rangefinder

We present a method for locally optimizing the parameters of an arbitrary weighting function used to smooth the error due to the discreteness of a distance sensor based on a frequency rangefinder. Then we analyze how additive noise affects the error of measurement and we derive an expression for the dispersion of the error. The possibility that optimization of the weighting function parameters can minimize the total error is examined.Translated from Izmeritelnaya Tekhnika, No. 12, pp. 19–23, December, 2004.This revised version was published online in April 2005 with a corrected cover date.     

Thermal Diffusivity of La1−x Sr x MnO3 (x < 0.3)

Perovskite manganites are interesting because of their colossal magnetoresistance. In this work high resolution thermal diffusivity measurements of La_1–x Sr _x MnO₃ (0 x 0.3) single crystals in the temperature range from 250 to 400 K are presented. A photopyroelectric device in the standard back configuration has been used. The thermal diffusivity through second-order magnetic phase transitions, as well as through first- and second-order structural phase transitions has been measured. The critical parameters of the sample with x = 0.3 at the ferromagnetic-to-paramagnetic transition have been obtained, and are close to the values predicted by the Ising model.     

Active monitoring of the geometrical dimensions of sliding bushings

A method and a measurement-control system for the nondestructive testing of the geometrical parameters of sliding bushings during their production are considered.Translated from Izmeritelnaya Tekhnika, No. 9, pp. 32–35, September, 2004.     

混凝土坝参数的随机反分析方法探讨

针对混凝土坝施工与运行过程中存在诸多的不确定性因素,基于随机理论和结构计算成果的分析,提出混凝土坝材料参数的随机反分析方法,研制开发了相应的优化计算分析程序。实例表明,随机反分析方法能较好地应用于混凝土坝材料参数的反演和识别中。