A Simple Method for Determining Kinetic Parameters for Materials in Fire Models

To predict the behaviour of biological wastewater treatment plants, the Activated Sludge Model No. 1 is often used. For the application of this model kinetic parameters and wastewater composition must be known. A simple method to estimate kinetic parameters of heterotrophic biomass and COD wastewater fractions is presented. With three different types of batch-tests these parameters and fractions can be determined by measuring oxygen respiration. Our measurements showed that the maximum specific growth rate µmax of heterotrophic biomass depends on temperature, reactor configuration and SRT. In typical wastewater treatment plants of Switzerland the amount of readily biodegradable substrate was generally small (about 9 % of the COD in primary effluent). The same method can also be used to determine kinetic parameters of nitrifying biomass.

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Acidic hydrolysis of astilbin and its application for the preparation of taxifolin from Rhizoma Smilacis Glabrae

Journal of Chemical Research ◽

10.1177/1747519820948357 ◽

2020 ◽

pp. 174751982094835

Author(s):

Xiao-Lin Qiu ◽

Qing-Feng Zhang

Keyword(s):

Activation Energy ◽

Kinetic Parameters ◽

Hydrolysis Reaction ◽

Simple Method ◽

Acidic Hydrolysis ◽

A Value ◽

Hcl Concentration ◽

Hydrolysis Of

The acidic hydrolysis of astilbin to produce its aglycone, taxifolin, was investigated in this study. The effects of aq. HCl concentration and temperature on the reaction were studied, and the kinetic parameters were calculated. The results showed that with higher aq. HCl concentration and temperature, the hydrolysis of astilbin became faster. The activation energy of the hydrolysis reaction under 1 mol L−1 aq. HCl was calculated with a value of 148.6 kJ mol−1. The reaction was successfully applied to produce taxifolin from a sample of Rhizoma Smilacis Glabrae. A simple method for the purification of taxifolin from Rhizoma Smilacis Glabrae was developed with purity of 97.5%.

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Fire modeling and information system technology

International Journal of Wildland Fire ◽

10.1071/wf01033 ◽

2001 ◽

Vol 10 (4) ◽

pp. 343 ◽

Cited By ~ 48

Author(s):

Patricia L. Andrews ◽

LLoyd P. Queen

Keyword(s):

Information System ◽

Information Systems ◽

Fire Management ◽

Fire Modeling ◽

System Technology ◽

Gis And Remote Sensing ◽

Fire Models ◽

Spread Model ◽

Information System Technology ◽

In Fire

This paper was presented at the conference ‘Integrating spatial technologies and ecological principles for a new age in fire management’, Boise, Idaho, USA, June 1999 Fire modeling and information system technology play an important supporting role in fuel and fire management. Modeling is used to examine alternative fuel treatment options, project potential ecosystem changes, and assess risk to life and property. Models are also used to develop fire prescriptions, conduct prescribed fire operations, and predict fire behavior. Fire models and information systems have greatly influenced fuel assessment methods. As an example, we examine the evolution of technology used to put Rothermel’s fire spread model into application. A review of fire and fuel modeling terminology is given, and the relationship between fire models and fuel models is explained. We review current fire modeling work and the influence that it will have on fuel characterization. Finally, we discuss opportunities and challenges involved in the use of advanced computers, the Internet, Geographic Information Systems (GIS), and remote sensing in fire and fuel management.

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Users' needs in fire models

Fire Technology ◽

10.1007/bf01041340 ◽

1988 ◽

Vol 24 (2) ◽

pp. 163-180

Author(s):

Robert S. Levine

Keyword(s):

Fire Models ◽

In Fire

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A simple method for the determination of adsorption kinetic parameters using circulating-type shallow bed reactor (CSBR)

10.5004/dwt.2017.21262 ◽

2017 ◽

Vol 92 ◽

pp. 1-8

Author(s):

Takashi Kawakita ◽

Huan-Jung Fan ◽

Yoshimi Seida ◽

Tomohiro Kinoshita ◽

Eiji Furuya

Keyword(s):

Kinetic Parameters ◽

Adsorption Kinetic ◽

Simple Method

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An Inverse Fire Modeling Methodology for the Determination of Fire Size, Fire Location, and Soot Deposition in a Compartment

Volume 7: Fluids and Heat Transfer, Parts A, B, C, and D ◽

10.1115/imece2012-88924 ◽

2012 ◽

Author(s):

Kristopher J. Overholt ◽

Ofodike A. Ezekoye

Keyword(s):

Gas Phase ◽

Solid Phase ◽

Fire Modeling ◽

Fire Intensity ◽

Intermediate Step ◽

Fire Size ◽

Fire Models ◽

Input Parameters ◽

In Fire ◽

Fire Location

Fire models are routinely used in life safety design projects and are being used more often in fire and arson investigations as well as reconstructions of firefighter line-of-duty deaths (LODDs) and injuries. In all of these applications, the fire heat release rate (HRR), location of a fire in a compartment, gas-phase soot concentration, and solid-phase soot accumulation are important parameters that govern the evolution of thermal conditions within the fire compartment. These input parameters can be a large source of uncertainty in fire models, especially in scenarios in which experimental data or detailed information on fire behavior are not available, such as fire investigations and LODD reconstructions. Various methods have been reported in literature to determine the size and location of a fire in a compartment using ceiling-mounted detectors [1–4]. A previous study by the authors developed an inverse fire modeling technique to determine the time-varying HRR of fire in a compartment using measured thermocouple data [5]. The work presented in this paper extends the inverse HRR methodology by developing a technique to determine the location of a fire using wall-mounted heat flux sensors or a surrogate such as degradation characteristics of enclosure boundaries that can be collected during post-fire assessments. Additionally, the presence of soot modifies the radiative transfer field in the hot gas layer (gas phase) as well as radiative heat transfer to surfaces (condensed phase). As a detailed history of compartment conditions becomes less available, there is a need for an inversion methodology to accurately recover governing input parameters such as fire size, fire location, and fire burning properties while maintaining an adequate level of accuracy. As an intermediate step using measured fire test data, we can begin to construct an approach to use rich data to invert for fire intensity, fire location, and fire properties such as the amount of soot produced by the fire.

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Historic global biomass burning emissions based on merging satellite observations with proxies and fire models (1750–2015)

10.5194/gmd-2017-32 ◽

2017 ◽

Cited By ~ 4

Author(s):

Margreet J. E. van Marle ◽

Silvia Kloster ◽

Brian I. Magi ◽

Jennifer R. Marlon ◽

Anne-Laure Daniau ◽

...

Keyword(s):

Biomass Burning ◽

Satellite Data ◽

Carbon Emissions ◽

Data Representation ◽

Atmospheric Composition ◽

Full Time ◽

Fire Emissions ◽

Fire Models ◽

Time Period ◽

In Fire

Abstract. Fires have influenced atmospheric composition and climate since the rise of vascular plants, and satellite data has shown the overall global extent of fires. Our knowledge of historic fire emissions has progressively improved over the past decades due mostly to the development of new proxies and the improvement of fire models. Currently there is a suite of proxies including sedimentary charcoal records, measurements of fire-emitted trace gases and black carbon stored in ice and firn, and visibility observations. These proxies provide opportunities to extrapolate emissions estimates based on satellite data starting in 1997 back in time, but each proxy has strengths and weaknesses regarding, for example, the spatial and temporal extents over which they are representative. We developed a new historic biomass burning emissions dataset starting in 1750 that merges the satellite record with several existing proxies, and uses the average of six models from the Fire Model Intercomparison Project (FireMIP) protocol to estimate emissions when the available proxies had limited coverage. According to our approach, global biomass burning emissions were relatively constant with 10-year averages varying between 1.8 and 2.3 Pg C year−1. Carbon emissions increased only slightly over the full time period and peaked during the 1990s after which they decreased gradually. There is substantial uncertainty in these estimates and patterns varied depending on choices regarding data representation, especially on regional scales. The observed pattern in fire carbon emissions is for a large part driven by African fires, which accounted for 58 % of global fire carbon emissions. African fire emissions declined since about 1950 due to conversion of savanna to cropland, and this decrease is partially compensated for by increasing emissions in deforestation zones of South America and Asia. These global fire emissions estimates are mostly suited for global analyses and will be used in the IPCC CMIP simulations.

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Estimation of dead fuel moisture content from meteorological data in Mediterranean areas. Applications in fire danger assessment

International Journal of Wildland Fire ◽

10.1071/wf06136 ◽

2007 ◽

Vol 16 (4) ◽

pp. 390 ◽

Cited By ~ 46

Author(s):

I. Aguado ◽

E. Chuvieco ◽

R. Borén ◽

H. Nieto

Keyword(s):

Moisture Content ◽

Fire Danger ◽

Second Phase ◽

Fuel Moisture ◽

Simple Method ◽

Danger Assessment ◽

Mediterranean Areas ◽

Field Samples ◽

Fuel Moisture Content ◽

In Fire

The estimation of moisture content of dead fuels is a critical variable in fire danger assessment since it is strongly related to fire ignition and fire spread potential. This study evaluates the accuracy of two well-known meteorological moisture codes, the Canadian Fine Fuels Moisture Content and the US 10-h, to estimate fuel moisture content of dead fuels in Mediterranean areas. Cured grasses and litter have been used for this study. The study was conducted in two phases. The former aimed to select the most efficient code, and the latter to produce a spatial representation of that index for operational assessment of fire danger conditions. The first phase required calibration and validation of an estimation model based on regression analysis. Field samples were collected in the Cabañeros National Park (Central Spain) for a six-year period (1998–2003). The estimations were more accurate for litter (r2 between 0.52) than for cured grasslands (r2 0.11). In addition, grasslands showed higher variability in the trends among the study years. The two moisture codes evaluated in this paper offered similar trends, therefore, the 10-h code was selected since it is simpler to compute. The second phase was based on interpolating the required meteorological variables (temperature and relative humidity) to compute the 10-h moisture code. The interpolation was based on European Centre for Medium Range Weather Forecasting (ECMWF) predictions. Finally, a simple method to combine the estimations of dead fuel moisture content with other variables associated to fire danger is presented in this paper. This method estimates the probability of ignition based on the moisture of extinction of each fuel type.

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