Properties of some statistics for AR-ARCH model with application to technical analysis

In this paper, we investigate some popular technical analysis indexes for AR-ARCH model as real stock market. Under the given conditions, we show that the corresponding statistics are asymptotically stationary and the law of large numbers hold for frequencies of the stock prices falling out normal scope of these technical analysis indexes under AR-ARCH, and give the rate of convergence in the case of nonstationary initial values, which give a mathematical rationale for these methods of technical analysis in supervising the security trends.     

The structure analysis of triaryl derivatives of the group V elements: V. Spectra,crystal and molecular structure of trimesitylarsine,C27H33As

The complete X-ray structure analysis of trimesitylarsine (TMAS), C₂₇H₃₃As, has been performed. The crystals are triclinic, a 18.718, b 16.418, c 8.204 Å, α 99.99, β 97.85, γ 104.56°, Z = 4, space group P1̄ (two independent molecules in the asymmetric unit); the final value of the R-factor is 0.038. In the electronic spectrum of TMAS the long-wave band has the maximum at 276 nm which differs significantly from that of triphenylarsine (TPAS) at 249 nm. The bathochromic spectral shift and the molecular conformation are caused by the steric effects as a result of bulky methyl groups in the positions 2,4 and 6 in the phenyl rings. Two independent molecules are connected by a pseudo-axis of symmetry.     

Supercritical fluid chromatographic separation of polychlorinated biphenyls (PCBs) using a negative temperature gradient for density programming

The technical PCB mixtures Aroclol and Clophen have been analyzed by packed column supercritical fluid chromatography using negative temperature programming. The chromatographic method was successfully applied to the analysis of PCBs, polycyclic aromatic hydrocarbons, and polychlorinated dibenzo-p-dioxins in extracts from environmental matrices.     

A survey of workload, facilities and awareness of uncertainty of measurement among Italian laboratories performing analyses in occupational and environmental medicine

Biological monitoring is essential for risk assessment in the presence of exposure of workers or the general population to harmful chemical agents. Besides the choice of analytical methods which are fit for purpose and the skills of the analysts, the performance of laboratories, including those working in the field of environmental and occupational medicine, also depends on other technical factors such as frequency of testing, the use of well maintained and properly functioning equipment and the implementation of quality control procedures including the participation in External Quality Assessment Schemes (EQAS). Surveys of laboratory workload have been organized periodically since 1997 within the MeTos Project, an Italian national EQAS for biomarkers of environmental and occupational exposure to chemical agents. In 2001, a more extensive survey, including specific technical issues, was organized as part of the activities of the Thematic Network of European Organizers of External Quality Assessment/Proficiency Testing Schemes Related to Occupational and Environmental Medicine (Network survey). In addition, information on the awareness and implementation of the new requirement for laboratories to estimate the uncertainty of their measurements was collected since 2000. The results of these surveys are reported and compared here. In all surveys, Pb in blood was the biomarker most frequently determined. As for biomarkers of exposure to organic compounds, the data collected in the Network survey indicate that methylhippuric acid, hippuric acid and mandelic acid in urine were the assays most commonly performed. About a third of the participants stated that they estimate the uncertainty of at least some of their measurements. Preliminary analysis of data, limited to Pb in blood, showed that analytical performance improved with continuous participation in EQAS and was positively influenced by a high workload.     

Trends in Polymer and Particle Characterization by Microfluidic Field-Flow Fractionation Methods: Science or Business?

More than 45 years have passed since the invention of field-flow fractionation (FFF). During this time, several methods and techniques, differing mainly by the nature of the applied field, have been proposed and experimentally implemented. However, only few of them are currently in practical laboratory use. Recent trends of miniaturization of all separation techniques have also been followed in the development of FFF apparatus. The aim of this work is to give an overview of the advances that are important in the practical use of microfluidic FFF techniques. Another aim is a critical evaluation of the crucial characteristics of the most widespread FFF techniques performed in standard-size channels.     

高职《高聚物合成技术》课程项目化教学改革研究

通过对国家骨干高职院校建设项目之课程建设的探索,从课程体系的整合、课程标准的更新、课程项目内容的选择与实施、考核评价体系的建立以及资源库建设等方面,阐述了目前我院《高聚物合成技术》专业课程项目化教学改革的具体思路及做法,体现了工学结合项目化教学改革对学生职业技能培养的重要性,旨在通过加强课程建设,优化课程结构,创设工学...