A new software package, Virtual Column 2, is described for the simulation and optimization of the separation of inorganic anions by ion chromatography (IC). The software uses a limited amount of experimental retention data acquired according to a correct experimental design to predict retention times for analytes over a designated search area of eluent compositions. The experimental retention d...

introduction wetlands are classified into four kinds of flows as subsurface, surface, vertical, and hybrid flows. usually, wetlands are planted with common reed (phragmites australis), a rhizomatose plant of the graminae which produces a good yield in green biomass and whose roots can reach a considerable depth and plays a significant role in the wetland self-purification. the treatment efficie...

abstract   background: the compounds which contain nitrogen entering the environment can cause some problems, such as eutrophication for water resources and potential risk for human health because of methemoglobinemia and cancer. biological techniques are effective in removing nitrate. the aim of this study was to remove nitrate from groundwater using denitrification. the main objectives of thi...

background: to identify and analyze factors that influence the grading and zoning management model of emergency triage as a first step in the improvement of the system. methods: questionnaires were used to extract data from clinical histories of 286 patients who attended the emergency department of binzhou central hospital (binzhou city, shandong province, china) from september to november of 2...

We developed a computational method to predict the retention times of peptides in HPLC using artificial neural networks (ANN). We performed stepwise multiple linear regressions and selected for ANN input amino acids that significantly affected the LC retention time. Unlike conventional linear models, the trained ANN accurately predicted the retention time of peptides containing up to 50 amino a...

The gas-liquid chromatographic retention times on 0.5% SP-525 for 48 bile acids and related compounds as their methyl ester acetate derivatives are given. Ion tables for electron impact spectra have been compiled that permit direct access to ion structures for any given ion mass. Chemical ionization yields highly simplified mass spectra with two or three ions predominating for each compound. Wh...

the aim of the current study was to investigate three volleyball skills in three training conditions of blocked, random and serial to reveal their effects in three phases of acquisition, retention and transfer. 60 amateur male students (mean age = 21.5 years, sd= 1.2) were voluntarily selected and randomly divided into three training groups (blocked, random and serial). a pretest was used to ma...

The analysis of organotin compounds is becoming increasingly important in both environmental analysis and in food and consumer product analysis. This application note describes a retention time locked (RTL) gas chromatography/mass spectrometry (GC/MS) method for the analysis of derivatized organotin compounds. Three retention time locked libraries are made available, corresponding to three diff...

BACKGROUND Studies and guidelines recommending the retention of the central venous catheter (CVC) in patients with coagulase-negative staphylococcal bacteremia were based on loose definitions of bacteremia and/or did not evaluate the risk of recurrence. In this study, we used strict definitions of coagulase-negative staphylococcal bacteremia to determine the impact of CVC retention on response ...