Note: Temperature derivative of the refractive index of binary mixtures measured by using a new thermodiffusion cell

A thermodiffusion cell is developed for performing Soret experiments on binary mixtures at high pressure and in the presence of a porous medium. The cell is validated by performing experiments at atmospheric pressure. The experiments are performed by applying different temperature gradients to binary mixtures in order to determine their thermal contrast factor. These measurements provide a first demonstration of the good reproducibility of this kind of measurements upon calibration.     

基于N-gram语言模型的哈萨克文机构名识别

针对哈萨克文文本中机构名构成特点,提出了一种基于N-gram语言模型的哈萨克文机构名可信度计算方法,并以机构名尾词为触发词,构建了一个哈萨克文机构名识别系统。系统分为训练和识别两个模块,识别过程是：首先从训练语料中提取特征进行训练,得到一个特征训练模型,然后利用训练好的特征模型及少量的附加规则,对测试文本中的机构名进行识别,实验结果表明该方法可行。     

Analysis of Non-Equilibrium Fluctuations In A Ternary Liquid Mixture

From the benchmark values of the diffusion and thermodiffusion coefficients of the tetralin, isobutylbenzene and n-dodecane ternary mixture, and the published optical contrast factors, we have evaluated the theoretical amplitudes of the two composition modes of the refractive-index fluctuations. Shadowgraph experiments have been performed on ground, where the current theory is expected to be correct only for large wave vectors. Two decay times have been observed experimentally. The fastest one being related to the thermal diffusivity of the mixture, while the slower one to mass diffusion. Hence, it has not been possible to distinguish the two eigenvalues of the mass diffusion matrix, a problem also encountered in traditional light-scattering with ternary mixtures of similar-size molecules. Thus, to compare the measured Intermediate Scattering Function with theory, we fix the amplitudes and decay rates to the benchmark values, use the wave number as a fitting parameter, and compare it to the experimental wave number. The good agreement between theory and experiments for the larger wave numbers validates the theory developed for the microgravity conditions.     

Evaluation of thermodynamic properties using GAB model to describe the desorption process of cocoa beans

The desorption isotherms and thermodynamic properties of cocoa beans were obtained during the drying process of this product. The isotherms were determined by dynamic method for various temperature (25, 35, 45 and 55 °C) and relative humidity (RH) conditions (30, 40, 50, 60, 70 and 80%). Equilibrium moisture content data were correlated by the Guggenheim–Anderson–de Boer (GAB) model, which presented good fit to the data, according to statistical procedures. Equilibrium moisture content ranged from 5.90 to 16.67 d.b.; it increased with an increment in the RH and decreased with increased temperature at a constant RH. Enthalpy values for each model coefficient were encountered, ranging from ?90.05 to 545.96 kJ kg^?1. The integral isosteric heat of desorption and differential entropy increased with decreased equilibrium moisture content, a tendency also found for Gibbs free energy.     

Iron determination by FAAS in fish feed and feces after ultrasound-assisted extraction

This paper proposes a method to determine iron in samples of fish feed and feces using ultrasound in the extraction of the analyte and in subsequent quantification by flame atomic absorption spectrometry. Using HCl 0.10 mol L⁻¹ as the extraction solution, the optimal conditions of extraction were found to be: granulometry of the sample <60 μm; a sonication time of five cycles of 10 s and sonication power of 136 W. The method was applied in studies of the availability of iron in four food sources used in the diet of Nile Tilapia. The results obtained with the proposed extraction method allowed us to calculate the coefficients of apparent digestibility of iron in the food sources, which was not possible when using results obtained from samples mineralized by acid digestion.     

Hepatorenal syndrome

The hepatorenal syndrome is a severe and common complication of patients with advanced cirrhosis and ascites. It is characterised not only by renal failure but also by marked alterations in systemic haemodynamics. Renal failure is due to a marked hypoperfusion of the kidney secondary to renal vasoconstriction. Although the pathogenesis of hepatorenal syndrome is not completely understood, it is thought to be the extreme manifestation of the underfilling of the arterial circulation secondary to an arterial vasodilation, located mainly in the splanchnic circulation. Recently, a revised definition and diagnostic criteria of hepatorenal syndrome have been proposed. The prognosis of patients with hepatorenal syndrome is very poor. Liver transplantation is the only effective treatment but it is not applicable in most cases due to short survival. New therapies developed during the last years, such as the use of systemic vasoconstrictors or transjugular intra-hepatic portosystemic shunts appear to be promising, but prospective investigations are needed to delineate their real usefulness.