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Control Standards (control + standards)
Selected AbstractsFlood control and land use management in Mengwa retention area, Huai River Basin,IRRIGATION AND DRAINAGE, Issue 4 2004Han Ruiguang Contrôle des crues; gestion de l'occupation du sol; aire d'épandage Abstract Retention areas have a very important role in flood alleviation in the Huai River Basin. With economic and societal development the former retention areas have been developed and some of them even became very important urban areas. When floods come, there is a lot of damage. The government has realized that the flood control standards in the whole river basin are low and has made a plan to increase flood control standards for the Mengwa retention area. The design water level will be 28.00,m+MSL at Runheji. In light of this the use of the Mengwa retention area needs to be considered. To arrive at decisions that reduce flood damage, one should take into account the following uncertainties: the river discharge, the flood damage given the discharge, the downstream water level given the discharge, and the costs of constructing embankments and dredging the river. By using the DUFLOW model and a GIS model, the present situation and the alternative development options have been analysed. How to use the Mengwa retention area is also discussed. Copyright © 2004 John Wiley & Sons, Ltd. Les zones d'expansion jouent un rôle important dans la réduction des crues du fleuve Huia. Ces zones ont connu le même développement économique et social que le reste de la région, et certaines sont maintenant fortement urbanisées. Les crues y provoquent beaucoup de dégâts. Le gouvernement a pris conscience que les critères pour contrôler les crues dans le bassin versant sont insuffisants, et a élaboré un plan pour améliorer ce contrôle dans l'aire d'épandage de Mengwa. Le niveau d'eau de référence retenu est à la cote 28,m, prise à Runheji. Ceci implique de reconsidérer l'utilisation de la zone d'expansion. Les décisions permettant de réduire les dégâts dus aux crues ont été élaborées à partir des paramètres suivants: débit du fleuve, relation entre le débit et les dégâts dus aux crues, niveau d'eau en aval, coûts de renforcement des digues, coût du dragage. La situation actuelle et les possibilités d'amélioration ont été analysées avec le modèle DUFLOW et un SIG. L'utilisation de la zone d'expansion de Mwenga est examinée également. Copyright © 2004 John Wiley & Sons, Ltd. [source] Simple method for determination of five terpenoids from different parts of Tripterygium wilfordii and its preparations by HPLC coupled with evaporative light scattering detectionJOURNAL OF SEPARATION SCIENCE, JSS, Issue 9 2007Xiao-Ling Luo Abstract By optimizing the extraction, separation, and analytical conditions, a reliable and accurate high-performance liquid chromatography method coupled with evaporative light scattering detection (ELSD) was developed for simultaneous determination of five terpenoids, i. e., triptolide, tripchlorolide, demethylzelastral, wilforlide B, and wilforlide A, in root, stem, leaves, root bark, twig, and root without bark of Tripterygium wilfordii Hook. f and six of its herbal preparations. This approach would thus provide a more accurate and general method for evaluating the quality of the herb and its preparations. Separation of these five terpenoids was achieved on a ZORBAX Eclipse XDB-C8 column with gradient elution using water and acetonitrile as solvents, both containing 0.05% formic acid, at a temperature of 30°C and a flow rate of 0.8 mL/min. The drift tube temperature of ELSD was set at 100°C, and the nitrogen flow rate at 1.5 L/min. Good linear relationships were obtained with correlation coefficients for the analytes exceeding 0.992, and the LOD and LOQ were less than 0.149 ,g and 0.297 ,g on column, respectively. Intra-day and inter-day precision of the analytes were less than 1.25% and 5.97%, respectively, and the average recovery rates obtained were in the range of 95.9 ± 3.7% to 100.4 ± 5.0% for all terpenoids with RSDs below 4.99%. Quantitative analysis of the five terpenoids in different parts of Tripterygium wilfordii and its six preparations showed that the contents of the terpenoids varied significantly. The tender root contained higher concentrations of triptolide, tripchlorolide, demethylzelastral, and wilforlide B than any other part of the herb. Correspondingly, the root bark contained the greatest concentration of wilforlide A, and the stem and twig came in second and third. This suggested that we could infer whether the medicinal materials were absolute roots without bark or not from the comparative contents of these terpenoids in the tablets in view of the fact that only the roots without bark are the valid officinal part of the plant. This method and the quantitation results obtained can provide a scientific and general as well as simple and convenient approach for the product manufacturers to set up quality control standards and for informing the public about the quality and safety of the preparations. [source] The detection of phenotypic differences in the metabolic plasma profile of three strains of Zucker rats at 20 weeks of age using ultra-performance liquid chromatography/orthogonal acceleration time-of-flight mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 19 2006Robert S. Plumb Analysis of biological fluids using ultra-performance liquid chromatography/mass spectrometry (UPLC/MS) (metabonomics) can allow new insights to be gained into disease processes, with advances in chromatographic techniques enabling the detection of thousands of metabolites. In this work metabonomics has been used to investigate the metabolic processes involved in type II diabetes in the Zucker obese rat. Plasma was analyzed from three different strains, the Zucker (fa/fa) obese, Zucker lean and the lean/(fa) obese cross. Using UPLC/MS, ca. 10,000 ions were detected due to the narrow peak widths and excellent peak shapes achieved with this technology. Confidence in the chromatographic performance was demonstrated by the use of quality control standards. The positive and negative ion total ion chromatograms obtained from the three strains were readily distinguishable using multivariate statistical analysis. The greatest difference was observed between the Zucker lean and Zucker lean/(fa) rats compared to the Zucker (fa/fa) obese rats. Positive ions m/z 220 (4.36,min), 282(3.78,min), 359 (5.33,min) and 405 (7.77,min) were elevated in the plasma derived from Zucker lean rats whilst ions m/z 385 (6.80,min) and 646 (4.36,min) were at a lower concentration compared to the plasma from the Zucker (fa/fa) obese animals. Negative ions elevated in the Zucker lean rats included m/z 212 (2.30,min), 514 (2.85,min), 295 (4.39,min), 329 (3.11,min), 343 (2.86,min) and 512 (2.86,min) with ions m/z 538 (4.18,min), 568 (4.18,min), 568 (5.09,min) and 612 (4.30,min) being raised in the samples derived from Zucker (fa/fa) obese animals. The ion m/z 514 (3.85,min) was found to correspond to taurocholate, providing further support for an involvement of taurine metabolism in diabetes. Copyright © 2006 John Wiley & Sons, Ltd. [source] Elements in the Sera of Preschool Children Living in Central TaiwanCHINESE JOURNAL OF CHEMISTRY, Issue 4 2007Chien-Yi Chen Abstract This study assessed elemental concentrations in the serum of 154 preschool children in central Taiwan via instrumental neutron activation analysis (INAA). A total of eight elements, Br, Cl, Fe, Na, Rb, Sc, Se and Zn of sera for Taiwanese preschool children living at four residential areas:Taichung city, Taichung urban townships and in a remote area inhabited by two groups of aborigines, Atayal and Bunun were determined. Standard reference materials (tomato leaves, NIST-SRM 1570a, and lichen, IAEA-336) were used as quality control standards to crosscheck the accuracy. Residential area, socioeconomic status and gender were shown to significantly influence serum levels of the eight trace elements. Statistical analysis revealed several different gender patterns via the two-tailed student's test. A quantified index of agreement (AT) was used to classify these elements. Small AT indicated a close consistency, while large AT indicated a larger fluctuation, or less agreement, such that the correlation between the elements could be interpreted using a series of quantified indices at the serum levels of preschool children. [source] | ||||||||||