Computer-assisted automatic peak recognition and result evaluation for analysis of chlorinated hydrocarbons in environmental samples

A data manipulation method has been developed for automatic peak recognition and result evaluation in the analysis of organic chlorinated hydrocarbons with dual-column gas chromatography. Based on the retention times of two internal standards, pentachlorotoluene and decachlorobiphenyl, the retention times of chlorinated hydrocarbons can be calibrated automatically and accurately. It is very convenient to identify the peaks by comparing the retention times of samples with the calibrated retention times calculated from the relative retention indices of standards. Meanwhile, with a suggested two-step evaluation method the evaluation coefficients and the suitable quantitative results of each component can be automatically achieved for practical samples in an analytical system using two columns with different polarities and two internal standards. (C) 2002 Elsevier Science B.V. All rights reserved.

Advanced arterial blood gas analysis in septic shock : a Singaporean nursing case review.

Introduction The admission to the Intensive Care Unit with a diagnosis of sepsis and/or septic shock is not uncommon. The aim of this article is to present a nursing case review of a patient admitted to the intensive care unit with a diagnosis of septic shock and the use of bedside acid–base formulae to inform clinical decision making. Method We chose to use a case review. This method is useful in reporting unusual or rare cases and is typically seen more in medicine than in nursing. Discussion The gentleman in question was a self-presentation with a short history of fever and worsening shortness of breath. His condition worsened where he required admission to the intensive care unit. The use of ‘advanced’ acid–base interpretation to guide his nursing care provided a platform from which to advance a deeper understanding of the intricacies the critically ill patient often presents. Conclusion The use of case review is enlightening in understanding the disease process and the decision-making that accompanies this. The lessons learnt are applicable to a wider nursing audience because understanding acid–base physiology is beneficial in supporting and advancing critical care nursing practice.

Insight into the thermal decomposition of kaolinite intercalated with potassium acetate : an evolved gas analysis

The thermal decomposition process of kaolinite–potassium acetate intercalation complex has been studied using simultaneous thermogravimetry coupled with Fourier-transform infrared spectroscopy and mass spectrometry (TG-FTIR-MS). The results showed that the thermal decomposition of the complex took place in four temperature ranges, namely 50–100, 260–320, 320–550, and 650–780 °C. The maximal mass losses rate for the thermal decomposition of the kaolinite–potassium acetate intercalation complex was observed at 81, 296, 378, 411, 486, and 733 °C, which was attributed to (a) loss of the adsorbed water, (b) thermal decomposition of surface-adsorbed potassium acetate (KAc), (c) the loss of the water coordinated to potassium acetate in the intercalated kaolinite, (d) the thermal decomposition of intercalated KAc in the interlayer of kaolinite and the removal of inner surface hydroxyls, (e) the loss of the inner hydroxyls, and (f) the thermal decomposition of carbonate derived from the decomposition of KAc. The thermal decomposition of intercalated potassium acetate started in the range 320–550 °C accompanied by the release of water, acetone, carbon dioxide, and acetic acid. The identification of pyrolysis fragment ions provided insight into the thermal decomposition mechanism. The results showed that the main decomposition fragment ions of the kaolinite–KAc intercalation complex were water, acetone, carbon dioxide, and acetic acid. TG-FTIR-MS was demonstrated to be a powerful tool for the investigation of kaolinite intercalation complexes. It delivers a detailed insight into the thermal decomposition processes of the kaolinite intercalation complexes characterized by mass loss and the evolved gases.

Evolved gas analysis of coal-derived pyrite/marcasite

The products evolved during the thermal decomposition of the coal-derived pyrite/marcasite were studied using simultaneous thermogravimetry coupled with Fourier-transform infrared spectroscopy and mass spectrometry (TG-FTIR–MS) technique. The main gases and volatile products released during the thermal decomposition of the coal-derived pyrite/marcasite are water (H2O), carbon dioxide (CO2), and sulfur dioxide (SO2). The results showed that the evolved products obtained were mainly divided into two processes: (1) the main evolved product H2O is mainly released at below 300 °C; (2) under the temperature of 450–650 °C, the main evolved products are SO2 and small amount of CO2. It is worth mentioning that SO3 was not observed as a product as no peak was observed in the m/z = 80 curve. The chemical substance SO2 is present as the main gaseous product in the thermal decomposition for the sample. The coal-derived pyrite/marcasite is different from mineral pyrite in thermal decomposition temperature. The mass spectrometric analysis results are in good agreement with the infrared spectroscopic analysis of the evolved gases. These results give the evidence on the thermal decomposition products and make all explanations have the sufficient evidence. Therefore, TG–MS–IR is a powerful tool for the investigation of gas evolution from the thermal decomposition of materials.

Paddock to Reef Monitoring and Evaluation: Economic analysis of ABCD cane management practices for the Mackay Whitsunday region

The economic analysis is based on the A, B, C and D management practice framework for water quality improvement developed in 2007/2008 by the respective natural resource management region. The Mackay Whitsunday ABCD management framework for sugarcane management practices was published in 2009 by the Department of Primary Industries & Fisheries (DPI&F), following the original version that was published in the Water Quality Improvement Plan: final report for Mackay Whitsunday region (2008).

Paddock to Reef Monitoring & Evaluation - Economic analysis of ‘ABCD’ cane management for Tully

The economic analysis is based on the A, B, C and D management practice framework for water quality improvement developed in 2007/2008 by the respective natural resource management region. This document focuses on the economic implications of these management practices in the Tully region. A review of the management practices is currently being undertaken to clarify some issues and incorporate new knowledge since the earlier version of the framework. However, this updated version is not yet complete and so the Paddock to Reef project has used the most current available version of the framework for the modelling and economics.

Paddock to Reef Monitoring and Evaluation - Economic analysis of ‘ABCD’ cane management for the Burdekin Delta region.

The economic analysis is based on the A, B, C and D management practice framework for water quality improvement developed in 2007/2008 by the respective natural resource management region. This document focuses on the economic implications of these management practices in the Burdekin Delta region. A review of the management practices is currently being undertaken to clarify some issues and incorporate new knowledge since the earlier version of the framework. However, this updated version is not yet complete and so the Paddock to Reef project has used the most current available version of the framework for the modelling and economics.

Paddock to Reef Monitoring & Evaluation - Economic analysis of ‘ABCD’ cane management for the Burdekin River Irrigation Area.

The economic analysis is based on the A, B, C and D management practice framework for water quality improvement developed in 2007/2008 by the respective natural resource management region. This document focuses on the economic implications of these management practices in the Burdekin River Irrigation Area (BRIA). A review of the management practices is currently being undertaken to clarify some issues and incorporate new knowledge since the earlier version of the framework. However, this updated version is not yet complete and so the Paddock to Reef project has used the most current available version of the framework for the modelling and economics.

Categorical Meteorological Products: Evaluation and Analysis

In meteorology, observations and forecasts of a wide range of phenomena for example, snow, clouds, hail, fog, and tornados can be categorical, that is, they can only have discrete values (e.g., "snow" and "no snow"). Concentrating on satellite-based snow and cloud analyses, this thesis explores methods that have been developed for evaluation of categorical products and analyses. Different algorithms for satellite products generate different results; sometimes the differences are subtle, sometimes all too visible. In addition to differences between algorithms, the satellite products are influenced by physical processes and conditions, such as diurnal and seasonal variation in solar radiation, topography, and land use. The analysis of satellite-based snow cover analyses from NOAA, NASA, and EUMETSAT, and snow analyses for numerical weather prediction models from FMI and ECMWF was complicated by the fact that we did not have the true knowledge of snow extent, and we were forced simply to measure the agreement between different products. The Sammon mapping, a multidimensional scaling method, was then used to visualize the differences between different products. The trustworthiness of the results for cloud analyses [EUMETSAT Meteorological Products Extraction Facility cloud mask (MPEF), together with the Nowcasting Satellite Application Facility (SAFNWC) cloud masks provided by Météo-France (SAFNWC/MSG) and the Swedish Meteorological and Hydrological Institute (SAFNWC/PPS)] compared with ceilometers of the Helsinki Testbed was estimated by constructing confidence intervals (CIs). Bootstrapping, a statistical resampling method, was used to construct CIs, especially in the presence of spatial and temporal correlation. The reference data for validation are constantly in short supply. In general, the needs of a particular project drive the requirements for evaluation, for example, for the accuracy and the timeliness of the particular data and methods. In this vein, we discuss tentatively how data provided by general public, e.g., photos shared on the Internet photo-sharing service Flickr, can be used as a new source for validation. Results show that they are of reasonable quality and their use for case studies can be warmly recommended. Last, the use of cluster analysis on meteorological in-situ measurements was explored. The Autoclass algorithm was used to construct compact representations of synoptic conditions of fog at Finnish airports.

Effects of ethanol on vehicle energy efficiency and implications on ethanol life-cycle greenhouse gas analysis.

Bioethanol is the world's largest-produced alternative to petroleum-derived transportation fuels due to its compatibility within existing spark-ignition engines and its relatively mature production technology. Despite its success, questions remain over the greenhouse gas (GHG) implications of fuel ethanol use with many studies showing significant impacts of differences in land use, feedstock, and refinery operation. While most efforts to quantify life-cycle GHG impacts have focused on the production stage, a few recent studies have acknowledged the effect of ethanol on engine performance and incorporated these effects into the fuel life cycle. These studies have broadly asserted that vehicle efficiency increases with ethanol use to justify reducing the GHG impact of ethanol. These results seem to conflict with the general notion that ethanol decreases the fuel efficiency (or increases the fuel consumption) of vehicles due to the lower volumetric energy content of ethanol when compared to gasoline. Here we argue that due to the increased emphasis on alternative fuels with drastically differing energy densities, vehicle efficiency should be evaluated based on energy rather than volume. When done so, we show that efficiency of existing vehicles can be affected by ethanol content, but these impacts can serve to have both positive and negative effects and are highly uncertain (ranging from -15% to +24%). As a result, uncertainties in the net GHG effect of ethanol, particularly when used in a low-level blend with gasoline, are considerably larger than previously estimated (standard deviations increase by >10% and >200% when used in high and low blends, respectively). Technical options exist to improve vehicle efficiency through smarter use of ethanol though changes to the vehicle fleets and fuel infrastructure would be required. Future biofuel policies should promote synergies between the vehicle and fuel industries in order to maximize the society-wise benefits or minimize the risks of adverse impacts of ethanol.

Fast response CO2 sensor for automotive exhaust gas analysis

A fast response sensor for measuring carbon dioxide concentration has been developed for laboratory research and tested on a spark ignition engine. The sensor uses the well known infra-red absorption technique with a miniaturized detection system and short capillary sampling tubes, giving a time constant of approximately 5 milliseconds; this is sufficiently fast to observe changes in CO2 levels on a cycle-by-cycle basis under normal operating conditions. The sensor is easily located in the exhaust system and operates continuously. The sensor was tested on a standard production four cylinder spark-ignition engine to observe changes in CO2 concentration in exhaust gas under steady state and transient operating conditions. The processed sensor signal was compared to a standard air-to-fuel ratio (AFR) sensor in the exhaust stream and the results are presented here. The high frequency response CO2 measurements give new insights into both engine and catalyst transient operation. Copyright © 1999 Society of Automotive Engineers, Inc.