bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of plasmid‐encoded functions in Rhizobium leguminosarum biovar trifolii using proteome analysis of plasmid‐cured derivatives
Authors: Guerreiro Nelson , Stepkowski Tomasz , Rolfe Barry G. , Djordjevic Michael A.
Published: May 2005

We have used proteome analysis of derivatives of R. leguminosarum biovar trifolii strain ANU843, cured of indigenous plasmids by a direct selection system, to investigate plasmid‐encoded functions. Under the conditions used, the plasmid‐encoded gene products contributed to only a small proportion of the 2000 proteins visualised in the two‐dimensional (2‐D) protein map of strain ANU843. The level of synthesis of thirty‐nine proteins was affected after curing of either plasmid a, c or e. The differences observed upon plasmid curing included: protein loss, up/down‐regulation of specific proteins and novel synthesis of some proteins. This suggests that a complex interplay between the cured plasmid and the remaining replicons is occurring. Twenty‐two proteins appeared to be absent in the cured strains and these presumably are encoded by plasmid genes. Of these, a small heat shock protein, a cold shock protein, a hypothetical YTFG‐29.7 kDa protein, and the alpha and beta sub‐units of the electron transfer flavoprotein were identified by N‐terminal micro‐sequencing and predicted to be encoded by plasmid e. Four of the sequenced proteins putatively encoded on plasmid e and two encoded on plasmid c were novel. In addition, curing of plasmid e and c consistently decreased the levels of 3‐isopropylmalate dehydratase and malate dehydrogenase, respectively, suggesting that levels of these proteins may be influenced by plasmid‐encoded functions. A protein with homology to 4‐oxalocrotonate tautomerase, which is involved in the biodegradation of phenolic compounds, was found to be newly synthesised in the strain cured of plasmid e. Proteome analysis provides a sensitive tool to examine the functional organisation of the Rhizobium genome and the global gene interactions which occur between the different replicons.
Cardiac protein abnormalities in dilated cardiomyopathy detected by two‐dimensional polyacrylamide gel electrophoresis
Authors: Corbett Joseph M. , Why Howard J. , Wheeler Colin H. , Richardson Peter J. , Archard Leonard C. , Yacoub Magdi H. , Dunn Michael J.
Published: May 2005

The aim of the investigation was to determine whether there are specific global quantitative and qualitative changes in protein expression in heart tissue from patients with dilated cardiomyopathy (DCM) compared with ischaemic heart disease and undiseased tissue. Two‐dimensional (2‐D) polyacrylamide gel electrophoresis and computer analysis was used to study protein alteration in DCM biopsy material (n=28) compared with donor heart biopsy samples (n=9) and explanted hearts from individuals suffering from ischaemic heart disease (IHD; n = 21). A total of 88 proteins displayed decreased abundance in DCM versus IHD material while five proteins had elevated levels in the DCM group (p<0.01). The most prominent changes occurred in the contractile protein myosin light chain 2 and in a group of proteins identified as desmin. These changes do not appear to be artefactual degradation events occurring during sample processing. These proteins are not apparent in electrophoretic separations of vascular tissue or cultured endothelial cells, mesothelial cells or cardiac fibroblasts, which are clearly distinguishable from the 2‐D protein patterns of whole heart and of isolated cardiac myocytes and do not appear to reflect variations in the cellular composition of biopsy samples. The different protein patterns observed in cardiomyopathy showed no obvious relationship with New York Heart Association (NYHA) functional class or haemodynamic parameters. The study has demonstrated significant alterations in quantitative protein expression in the DCM heart which would have serious implications for myocyte function. These changes might be explained by altered protease activity in DCM which could exacerbate contractile dysfunction in the failing heart.
Capillary electrophoresis, nuclear magnetic resonance and mass spectrometry studies of opposite chiral recognition of chlorpheniramine enantiomers with various cyclodextrins
Authors: Chankvetadze Bezhan , Burjanadze Naira , Bergenthal Dieter , Strickmann Dirk , Blaschke Gottfried , Pintore Giorgio , Cerri Riccardo
Published: May 2005

Markedly different chiral separation abilities were observed for native β‐cyclodextrin (β‐CD), carboxymethyl‐β‐CD (CM‐β‐CD) and heptakis (2,3,6‐tri‐O‐methyl)‐β‐CD (TM‐β‐CD) towards the enantiomers of (±)‐chlorpheniramine ((±)‐CHL) in capillary electrophoresis (CE). Native β‐CD afforded almost baseline enantioseparation at a concentration of 18 mg/mL, whereas only 1 mg/mL solution of CM‐β‐CD was required for adequate enantioseparation. TM‐β‐CD allowed the nearly baseline enantioseparation only at a concentration as high as 80 mg/mL. Moreover, the migration order of (±)‐CHL in the presence of TM‐β‐CD was opposite to that with β‐CD and CM‐β‐CD. 1H and 13C‐NMR spectroscopy and electrospray ionization mass spectrometry (ESI‐MS) have been used in order to obtain preliminary information about the stoichiometry and the binding constants in the intermolecular diastereomeric complexes of (±)‐CHL with these CDs.
Capillary electrophoresis of anions at high salt concentrations
Authors: Ding Weiliang , Thornton Michelle J. , Fritz James S.
Published: May 2005

It is commonly thought that even a moderately high ionic concentration in the background electrolyte (BGE) would leaad to Joule heating and serious peak distortion. However, we obtained very satisfactory separations of both inorganic and organic anions in electrolyte solutions as high as 5 M sodium chloride using direct photometric detection. Samples containing a 0.5 M concentration of a salt can be analyzed directly by making the BGE concentration of the same salt even higher to obtain electrostacking. The temperature in the center of the capillary was calculated to be 49°C when the current is at its maximum of 280 μA. The effect of various salts on electrophoretic and electroosmotic mobility is discussed. Several examples are given of capillary electrophoresis under high‐salt conditions.
Characterization of micelles by capillary electrophoresis
Authors: Schwarz Maria A. , Raith Klaus , Neubert Reinhard H. H.
Published: May 2005

A practical approach for the characterization of pure micelles, and binary or ternary mixed micelles by capillary electrophoretic methods is presented. Interest is focused on the determination of mobility and composition of the micelles. The investigations are performed with bile salts, phosphatidylcho‐lines and fatty acids. Pure bile salt micelles are characterized with the help of marking and displacement methods. Binary bile salt/phospholipid and ternary bile salt/phospholipid/fatty acid micelles are analyzed using capillary electrophoresis (CE) techniques with standard and improved UV detection, laser‐induced fluorescence and electrospray ionization ‐ mass spectrometry (ESI‐MS). For both the binary and the ternary systems, only one stable mixed micellar phase is found with a high negative mobility.
On‐line capillary electrophoresis‐electrospray ionization mass spectrometry using a polymerized anionic surfactant
Authors: Lu Wenzhe , Shamsi Shahab A. , McCarley Tracy D. , Warner Isiah M.
Published: May 2005

On‐line capillary electrophoresis ‐ electrospray ionization ‐ mass spectrometry (CE‐ESI‐MS) has been used to determine the tricyclic antidepressant drugs (imipramine, doxepin, and amitriptyline) as well as the β‐adrenergic blocker drugs (propranolol and alprenolol). A CE‐ESI‐MS interface linking a manually operated CE system and a Finnigan MAT‐900 sector mass spectrometer (with an Analytica electrospray ionization source) has been constructed in‐house and employed for this study. Although a water/methanol based capillary zone electrophoresis (CZE) buffer was initially used to determine these analytes, enhanced resolution was obtained by addition of a polymerized surfactant, i.e., poly‐sodium undecylenic sulfate (poly‐SUS), into the electrokinetic chromatography (EKC) buffer. When a low concentration of this poly‐SUS surfactant was added to a volatile EKC buffer, these structurally similar cationic drugs were EKC separated and on‐line detected by ESI‐MS.
Capillary electrophoresis and capillary electrophoresis ‐ electrospray ‐ mass spectroscopy for the analysis of heterocyclic amines
Authors: Zhao Yining , Schelfaut Marc , Sandra Pat , Banks Fred
Published: May 2005

Fourteen heterocyclic amines (HAs) were analyzed by capillary electrophoresis (CE) on a polyvinyl alcohol (PVA)‐coated capillary column. The optimized electrolyte is composed of 20 mM ammonium acetate, pH 3.0, and 20% methanol. Similar conditions were applied in electrospray ‐ mass spectrometry (CE‐ES‐MS). The CE‐ES‐MS optimization procedure includes the position of the capillary in the stainless steel interface, the flow of the sheath liquid and its composition.
Simultaneous measurement of α‐amylase and glucoamylase activities in sake rice koji by capillary electrophoresis of sodium dodecyl sulfate‐protein complexes and activity measurement of glucoamylase by in‐capillary enzyme reaction method
Authors: Watanabe Toshiro , Yamamoto Akira , Nagai Shiro , Terabe Shigeru
Published: May 2005

Capillary electrophoresis (CE) of sodium dodecyl sulfate (SDS)‐protein complexes using a nongel sieving matrix (CE‐SDS) has been applied to the simultaneous analysis of α‐amylase and glucoamylase activity in sake rice koji which is employed for the brewing of sake. α‐Amylase and glucoamylase in sake rice koji extracts were successfully analyzed by CE‐SDS. α‐Amylase and glucoamylase were found to have molecular masses of 53 000 and 63 000 Da, respectively, as determined by the migration times of eight standard proteins. These values agree with those determined by SDS‐polyacrylamide gel electrophoresis (PAGE). The results of CE‐SDS method were compared with those achieved by the official method. The relative standard deviations (RSD) of the α‐amylase and glucoamylase activities by CE‐SDS were less than 5.0% in both intra‐day and inter‐day experiments. An electrophoretic analysis of products of an enzyme reaction of a substrate by in‐capillary reaction was also useful for the activity measurement of glucoamylase in sake rice koji. p‐Nitrophenyl‐β‐D‐maltoside (PNP‐Mal) was employed as a substrate and p‐nitrophenyl‐β‐D‐glucopyranoside (PNP‐Glu) was the product of the enzyme reaction. The glucoamylase activity of sake rice koji samples gave the good linear relationship with the peak area observed in the in‐capillary enzyme reaction method. The glucoamylase activity in sake rice koji was measured by either CE‐SDS or the in‐capillary enzyme reaction more easily than by the official method. Both methods can be applied to the routine quality control of α‐amylase and glucoamylase activities in sake rice koji.
High resolution analysis of protein phosphorylation using capillary isoelectric focusing ‐ electrospray ionization ‐ mass spectrometry
Authors: Wei Jing , Yang Liyu , Harrata A. Kamel , Lee Cheng S.
Published: May 2005

On‐line capillary isoelectric focusing (CIEF)‐electrospray ionization ‐ mass spectrometry (ESI‐MS) as a two‐dimensional separation system is employed for high resolution analysis of ovalbumin phosphorylation. On the basis of their differences in isoelectric point (pI), the mono‐ and diphosphoovalbumins are separated and resolved in CIEF. The focused protein zones of mono‐ and diphosphoovalbumins are eluted by combining gravity with cathodic mobilization. At the end of the CIEF capillary, the mobilized ovalbumin zones are analyzed by mass spectrometry coupled on‐line to an electrospray interface with a coaxial sheath flow configuration. Additional ovalbumin variants within each of the mono‐ and diphosphoovalbumins, differing in their molecular masses due to glycosylation microheterogeneity, are easily distinguished by ESI‐MS.
Genotyping metabolic polymorphisms in a cohort of Caucasians and single strand conformation polymorphism analysis of point mutations in human hprt exons 7 and 8
Authors: Krause Günter , Garganta Fátima , Kosytorz Patrick , Scherer Gerhard
Published: May 2005

In genetic toxicology, the main fields of applications of the polymerase chain reaction (PCR) with subsequent electrophoretic characterization of amplificates include genotyping polymorphisms in the xenobiotic metabolism and mutant analysis. To assess the role of the individual sets of biotransformation enzymes for the internal dose resulting from xenobiotic exposure, we investigated blood samples from 69 healthy donors for the occurrence of known genetic polymorphisms in the xenobiotic metabolizing enzymes N‐acetylaminotransfrase II (NAT2), glutathione‐S‐transferase (GST) μ and θ, and several cytochromes P450 (CYP), namely CYP1A1, CYP2E1 and CYP2A6. Using single strand conformation polymorphism (SSCP) analysis, five known single base substitutions located in the middle portion of 144 bp amplificates comprising exons 7 and 8 of the human hypoxanthine guanine phosphoribosyl transferase (hprt) cDNA, were clearly distinguished from wild type and from each other. Biomagnetic strand separation assigned the slower migrating single strand bands to the biotinylated sense strands.
Separation of inorganic and organic anions by capillary zone electrophoresis with simultaneous indirect UV and conductivity detection
Authors: Klampfl Christian W. , Katzmayr Martin U. , Buchberger Wolfgang
Published: May 2005

The analysis of low‐molecular‐mass anionic compounds using capillary zone electrophoresis (CZE) with simultaneous direct conductivity and indirect UV detection is described. A number of carrier electrolyte compositions has been investigated with respect to the crucial parameters for their compatibility with both detection principles discussed in this paper (UV absorptivity and electrophoretic mobility of the buffer coion). Additionally, parameters including pH and buffer concentration affecting both peak symmetry and signal‐to‐noise ratio obtained for the analytes of interest had to be optimized. Best results could be achieved with a carrier electrolyte consisting of 4‐aminobenzoic acid, bis(2‐hydroxyethyl)imino‐tris(hydroxymethyl)aminomethane (BIS‐Tris) and a pH of 7.0 adjusted with LiOH. This running buffer was used for the analysis of low‐molecular‐mass anionic compounds in a sample of white wine.
Off‐line quantitative monitoring of plasmid copy number in bacterial fermentation by capillary electrophoresis
Authors: Breuer Susanne , Marzban Gorji , Cserjan‐Puschman Monika , Dürrschmid Eberhard , Bayer Karl
Published: May 2005

Capillary electrophoresis (CE) is an effective instrumental alternative to conventional slab gel electrophoresis in the determination of plasmid copy number during recombinant protein formation processes. This analytical setup provides efficient separation of different species of linearized plasmid molecules and quantification by UV detection. Both fused silica and gel‐filled capillaries are assessed with respect to peak resolution and reproducibility. The application of coated capillaries eliminates the electroosmatic flow to a large extent, resulting in excellent separation of DNA fragments. The application of UV detection enables the analysis of linearized plasmid DNA with a conventional laboratory CE device. All investigated plasmids show good peak resolution due to their significant differences in molecular size, which is essential for sufficient separation of individual DNA molecules.
Differential expression of cytosolic proteins in the rat kidney cortex and medulla: Preliminary proteomics
Authors: Witzmann Frank A. , Fultz Carla D. , Grant Raymond A. , Wright Lynda S. , Kornguth Steven E. , Siegel Frank L.
Published: May 2005

The rodent kidney is a target of many xenobiotics and is typified by regionally specific structure and function. This renders distinct regions of the kidney differentially susceptible to toxic exposure and effect. To characterize these differences at the proteome level, protein patterns from male rat kidney cortex and medulla cytosols were examined by two‐dimensional electrophoresis (2‐DE) and image analysis and prominent proteins identified immunologically or by matrix‐assisted laser desorption/ionization ‐ mass spectrometry (MALDI‐MS) and electrospray/ionization ‐ tandem mass spectrometry (ESI‐MS/MS) sequence tag identification. An average of 727 protein spots were resolved and matched to the cortex cytosol reference pattern, and 716 in the medulla. Of this total, 127 proteins were found to differ in abundance (86 higher in cortex; 41 higher in medulla) (P < 0.001). Of those proteins that were detectable in both cortex and medulla, the abundance of 97 differed significantly while 30 proteins were found to be unique to one region or the other (26 in cortex, 4 in medulla). Twenty protein spots were identified and their regional differences are discussed. These results both confirm and expand our understanding of the molecular heterogeneity characterizing structurally and functionally distinct regions of the kidney and serve as a useful foundation for future nephrotoxicologic studies.
Identification of minor proteins of human colostrum and mature milk by two‐dimensional electrophoresis
Authors: Murakami Kouki , Lagarde Margaret , Yuki Yoshikazu
Published: May 2005

Two‐dimensional electrophoresis (2‐DE) followed by electroblotting and microsequencing is considered to be the most powerful method for the isolation and characterization of proteins. In this paper, we report the separation and determination of the N‐terminal and/or internal amino acid sequences of the minor proteins of human colostral and mature milk by 2‐DE and microsequencing. In order to analyze the minor proteins of human milk, we use immunoabsorbents to remove three major proteins, α‐lactalbumin, lactoferrin and secretory immunoglobulin A. The major proteins removed by this process accounted for about 79 and 93% of the total whey proteins of mature and colostral milk, respectively. The remaining milk proteins were then separated by isoelectric focusing gel electrophoresis between pH 3 and 10, and subjected to 12.5% sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE). Approximately 400 spots were detected in both colostral and mature milk by silver staining after 2‐DE. Twenty‐two major, well‐resolved proteins (out of 400) were microsequenced (N‐termini as well as internal). These include fatty acid binding protein, β2‐microglobulin, complement C4, clusterin, α1‐antritrypsin, lysozyme C, α‐ and β‐casein, prealbumin, serotransferrin, fructose‐bisphosphate aldolase A, and β‐casein fragments. No major differences in the protein patterns were observed between the minor proteins of colostrum and mature milk, indicating that the minor proteins remained relatively constant during lactation. These results suggest that the minor milk proteins are important for the health and development of breast‐fed infants throughout lactation.
Electrophoretic methods for process monitoring and the quality assessment of recombinant glycoproteins
Authors: Taverna Myriam , Tran Nguyet Thuy , Merry Tony , Horvath Eszter , Ferrier Danielle
Published: May 2005

In many ways electrophoretic techniques appear ideal for quality monitoring of proteins and are thus well suited for the analysis of recombinant glycoproteins. The requirements of high throughput, comparative analysis and resolution of many variants are met by several electrophoretic techniques. A wide variety of such techniques are available to biotechnologists in the rapidly developing area of recombinant glycoproteins. It is the aim of this review to specifically cover recent work which has been applied to the analysis of DNA‐derived glycoproteins, both from a process control standpoint and final product validation. All major areas of electrophoresis including sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE), isoelectric focusing and techniques utilizing capillary electrophoresis are covered, with emphasis on analysis of glycoforms and oligosaccharide profiles of recombinant glycoproteins. As illustration, actual examples rather than standard glycoproteins are given to indicate the potential and limitations which may be encountered. It is anticipated that this review will prove a useful and practical guide to the latest developments by indicating the relevant merits of different methods.
Capillary affinity chromatography and affinity capillary electrophoresis of heparin binding proteins
Authors: Wu Xiaojun , Linhardt Robert J.
Published: May 2005

A new approach for separation, capillary affinity chromatography, is introduced for studying the interaction of heparin with antithrombin III and secretory leukocyte proteinase inhibitor. Heparin is covalently immobilized on the surface of an etched capillary through a silane spacer. The proteins are injected into the heparinized capillary, bound to the heparin, washed with buffer, eluted with sodium chloride in the same buffer using a pressure injection mode and eluting protein detected by absorbance. The resulting affinity separation is similar to that obtained from traditional affinity chromatography. The quantity of loaded protein in capillary affinity chromatography is at the nanogram level, offering an improvement over the milligram levels required for standard affinity chromatographic methods.
Separation of 1‐phenyl‐3‐methyl‐5‐pyrazolone derivatives of monosaccharides by capillary electrochromatography
Authors: Suzuki Shigeo , Yamamoto Mayumi , Kuwahara Yuri , Makiura Kyoko , Honda Susumu
Published: May 2005

1‐Phenyl‐3‐methyl‐5‐pyrazolone (PMP) derivatives of component monosaccharides in glycoproteins (fucose, galactose, mannose, N‐acetylgalactosamine and N‐acetylglucosamine) and epimeric aldopentoses (arabinose, lyxose, ribose and xylose) were well separated from each other by capillary electrochromatography on a Hypersil ODS column with a mixture of 50 mM N‐(2‐hydroxyethyl)piperazine‐2′‐(2‐ethanesulfonic acid) buffer, pH 6.0 to ∼ 6.3, and acetonitrile (2.2:1 v/v) as eluent. The elution of these compounds showed relatively strong dependence on the pH and concentration of the buffer salts contained in the eluent, as compared to the elution by pressure‐driven high‐performance liquid chromatography (HPLC) on the same stationary phase, but separation of PMP‐monosaccharides was better than that by HPLC. Retention times of PMP‐monosaccharides were highly reproducible with a relative standard deviation (RSD) of ∼ 0.6%, and quantification with an RSD less than 5% could be achieved using 3‐O‐methylglucose as an internal standard.
Multiple parameter cross‐species protein identification using MultiIdent ‐ a world‐wide web accessible tool
Authors: Wilkins Marc R. , Gasteiger Elisabeth , Wheeler Colin H. , Lindskog Ingrid , Sanchez Jean‐Charles , Bairoch Amos , Appel Ron D. , Dunn Michael J. , Hochstrasser Denis F.
Published: May 2005

Recent increases in the number of genome sequencing projects means that the amount of protein sequence in databases is increasing at an astonishing pace. In proteome studies, this is facilitating the identification of proteins from molecularly well‐defined organisms. However, in studies of proteins from the majority of organisms, proteins must be identified by comparing analytical data to sequences in databases from other species. This process is known as cross‐species protein identification. Here we present a new program, MultiIdent, which uses multiple protein parameters such as amino acid composition, peptide masses, sequence tags, estimated protein pI and mass, to achieve cross‐species protein identification. The program is structured so that protein amino acid composition, which is highly conserved across species boundaries, first generates a set of candidate proteins. These proteins are then queried with other protein parameters such as sequence tags and peptide masses. A final list of database entries which considers all analytical parameters is presented, ranked by an integrated score. We illustrate the power of the approach with the identification of a set of standard proteins, and the identification of proteins from dog heart separated by two‐dimensional gel electrophoresis. The MultiIdent program is available on the world‐wide web at: http://www.expasy.ch/sprot/multiident.html.
Biological evaluation of the toxicity of products of pyrolysis and combustion of materials
Authors: Herpol Claire
Published: May 2005

This paper present observations on the toxicity of gases produced by materials under three different combustion conditions. The difficulty of the general problem of toxicity is emphasized and the impossibility—at the present stage in the research—of satisfying the increasing pressure to establish toxicity safety regulations is stated.
The use of the setchkin apparatus—mass spectrometry in the investigation of ignition and burning of flame retarded polystyrenes
Authors: Masařík I. , Ryska M. , Světlík J. , Horák Z.
Published: May 2005

A review is given of the possibilities for the use of the Setchkin apparatus combined with mass spectrometry in the investigation of the gaseous products of the thermo‐oxidative decomposition and burning of flame‐retarded polystyrenes, with simultaneous determination of the characteristics of ignition. Information on flame‐retardants in polystyrene, and their effect on the inhibition of burning in the gaseous phase were provided by mass fragmentation analysis of the main components of decomposition and burning.
Toxicity of thermal degradation products of polyethylene and polypropylene
Authors: Michal Jan , Mitera Jiřía , Tardon Stanislav
Published: May 2005

Pyrolysis, thermo‐oxidation and combustion of polyethylene and polypropylene were studied and the products of these thermal degradation processes were identified by means of gas chromatography and gas chromatography‐mass spectrometry. The individual products of thermal degradation were evaluated for their toxicity and a conclusion on presumed toxic effect of the combustion products of the polymers studied has been drawn.
Calculation of a toxicity index for materials, based on a biological evaluation method
Authors: Herpol Claire , Vandevelde Paul
Published: May 2005

An attempt has been made to present toxicological results obtained by a biological evaluation method in a simple and comprehensive way. The calculation of a toxicity index which expresses mortality rates as a function of the very important time factor is proposed. Additionally it is shown how such an index could be used to rank a series of twenty materials according to their relative toxicity.
The effect of pyrolysis and combustion temperatures on smoke density
Authors: Edgerley P. G. , Pettett K.
Published: May 2005

The small‐scale smoke testing apparatus now proposed as a standard in France under the designation NF–T51–073 measures the total obscuration from a stream of smoke generated from a small sample. Although like other small‐scale fire tests, it is not claimed to be of relevance to real fire situations, it is possible by varying the temperature over a wide range (200–900°C) to obtain a plot of specific optical density for various materials which broadly corresponds with general experience and certain other smoke tests. The plots show that nearly all flammable substances give a rapid rise in smoke opacity in the 350–500°C region above which there is always a steep drop sometimes to smoke densities of virtually zero. Apart from one or two synthetic materials which show a very low smoke density through‐out, there is no general trend as between natural and synthetic substances. Oxygen depletion which often occurs in a real fire situation has some effect on the smoke density but it is not a major one. On the other hand, in some cases reheating the smoke can have quite a dramatic effect, due very probably to further pyrolysis and combustion.
Visualization of room fire induced smoke movement and flow in a corridor
Authors: Quintiere J. G. , McCaffrey B. J. , Rinkinen W.
Published: May 2005

A study was conducted of the smoke and flow field in a corridor subject to a room fire. The study was conducted using a scale model of roughly 0.35 m in height. The effect of corridor‐exit doorway width was recorded while the room doorway and fire‐room temperature were maintained constant. Smoke was generated from cotton wads soaked with titanium tetrachloride which produces white particles of titanium dioxide. By this means, the smoke layer resulting from the room fire and the corridor flow characteristics were visualized. The results show the lowering interface of the corridor smoke layer with decreasing corridor‐exit door width. Also a four‐layer horizontal counter‐current flow pattern was displayed and shown to result from a restriction (e.g. soffit) at the corridor exit. The mixing of the incoming cold flow and exiting hot flow at the corridor exit was observed to be shedding vortices swept into the cold floor jet. Results based on velocity measurements and smoke observations are presented for the corridor smoke layer height and doorway neutral‐plane heights. The limitations of current predictive models are demonstrated for layer‐heights and flow rates for the room and corridor experiments.
Interactions between flame retardants and stabilizers in polyethylene systems
Authors: Nagy P. , Szöllösi I. , Pál G.
Published: May 2005

The influence of flame retardants and stabilizers on the thermooxidative and thermal stability of polyethylene systems has been investigated. In the present study 18 polymeric composites were prepared and their stabilities investigated by static and dynamic methods; their flammability parameters were also determined.
The effect of turbulence on the combustion of gases
Authors: Makepeace R.
Published: May 2005

This is an extensive review of the work done on the effect of turbulence on combustion of gases.
Relative toxicity of pyrolysis gases from materials: Specific toxicants and special studies
Authors: Hilado Carlos J. , Cumming Heather J. , Machado Anne M.
Published: May 2005

Various aspects of Pyrolysis gas toxicity studies at the University of San Francisco are discussed. Animal response data can be used to establish patterns which would help identify specific toxicants by their mode of action. Reference time‐concentration curves for individual gaseous toxicants can be used to permit deduction of importance of these toxicants in complex mixtures of toxic gases. These techniques can be used to identify cause and mechanisms of toxicity without significant additional cost. The versatility and economy of the basic test permits rapid survey of test variables to identify potential problem situations.
Standards for the fire hazard of clothing: The Australian experience
Authors: Gordon Peter G.
Published: May 2005

The Australian Children's Nightwear Standards have been accepted as the basis of legislation in all States of Australia and by the Commonwealth Government. The standards are based on the philosophy that garment design as well as combustion characteristics of the material is an important consideration in assessing the fire hazard of nightwear. Using this approach a classification system has been devised which place children's nightwear into three categories of potential fire hazard. If a garment cannot be classified then it cannot be legally sold in Australia. The combustion characteristics tested are ease of ignition, rate of flame propagation and surface burn properties. For classification all materials used for children's nightwear must pass the latter test. The design of the standard test methods, criteria for classification and the concepts of safe design were developed by collection data from burns accidents and burnt clothing from accident victims from the burns research unit of a large children's hospital and by the study of the burning behavior of clothing on a manikin. The combustion criteria are not so stringent as to require the use of inherently flame resist materials or the use of flame retardant finishes. This approach in combination with safe design criterial enable commercially available textiles to meet the legislative requirements for children's nightwear. This mean that the nightwear standards are inexpensive to attain and do not require a sophisticated textile technology. A consumer labeling system has been designed to describe the three categories but yet there is no evidence to suggest that this had had any effect in reducing the number of burns accidents—consumers apparently regrading safe nightwear as a low priority. An inconsistent aspect of the calssification system is the incorporation into the standards in 1977 of criteria to prevent the classification of cotton flannelette nightdresses and the incorporation of arbitrary requirements for other nightdress containing cotton. These inconsistencies have been caused fundamentally by a problem which continues to bedevil the writing of good standards in Australia—that is, the lack of nationwide statistics on burns accidents.
The effect of environmental temperature upon the physical characteristics of the smoke produced by burning wood and PVC samples
Authors: Powell E. A. , Bankston C. P. , Cassanova R. A. , Zinn B. T.
Published: May 2005

Data are presented which show the effect of elevated environmental temperature upon smoke particle characteristics of wood (Douglas fir) and a rigid PVC, under both flaming and nonflaming combustion in air. The physical data obtainbed include the smoke particle average diameter, the smoke optical densities in red and blue light, and the weight loss of the sample. The average particle dimeter, the smoke optical densities in red and blue light, and the weight loss of the sample. The average particle diameter and optical densities in red and blue light, and the weight loss of the sample. The average particle dimater and optical densities were obtained uwing in in situ optical system which measures forward scattered light at two angles and transmitte light at two wavelengths. Data were taken for vertically mounted samples exposed to a radiant flux of 5 W cm−2 in environments at a room temperatures, 100°C, 200°C and 300°C. The result indicate that in flaming test higher environmental temperatures general result in greater smoke optical densities and larger smoke particles, while in nonflaming tests higherl temperatures in lower smoke densities and smaller smoke particles, for wood. These results may explain why small‐scale test data (room temperature environment) do not often correlate well with full‐scale data (often at elevated environmental temperatures).
Fire safety analysis for public mass transit trains
Authors: Allender P. J.
Published: May 2005

With increasing use of electric trains carrying very high passenger loads it is important to assess the risks involved in using combustible materials. An approach using decision tree methods to analyse the resulting fire growth and passenger action combinations has been developed. Clear statement of objectives, mainly preservation of life and property, is essential. Systems analysis models can then be used to define the nature of quantitative information needed to assess probabilities of the lines of action shown by the decision tree. The current situation is not fully defined since there isdifficulty in using test report and behavioural information in the on‐off mode needed for Boolean logic which is required by decision tree methods. Some preliminary probabilities are given for state transitions, such as ignition to flame spread, based on reported data. A basis for a possible approach to human behaviour variables and the effect of combustion products is given.
Textiles, fire and test standards—a polemic
Authors: Clegg D.
Published: May 2005

Textiles usually form the exterior surface of an item which they cover. They are usually organic and therefore may be readily burned. Some actively spread flame. Thus, they are vunerable to fire and to controls designed to promote fire safety. This paper is essentially a personal view of the diversity of test methods, standards and controls concerned with textile flammability which have emerged or are emerging internationally. It suggests the need for collaboration in assessing fire hazards rationally, to counter emotive pressures for controls for controls and to promote their harmonization worldwide.
A method for measuring combustion intermittency in fires
Authors: Chitty R. , Cox G.
Published: May 2005

This note describes a digital circuit for the measurement of combustion intermittency in fire gases. The measurement has been achieved by analyzing the positive ion current drawn by an electrostatic probe immersed in the flow. The circuits used are modular in design so that signals from different types of sensor may be presented for intermittency analysis. Some results obtained in an unbounded diffusion flame are reported.
Two‐layer modeling of smoke movement in building fires
Authors: Zukoski E. E. , Kubota Toshi
Published: May 2005

A description is given of a model which predicts the motion of combustion products and fresh air caused by a fire located in one room of a two‐room structure. The gas in each room is assumed to be divided into two homogeneous layers, a layer next to the ceiling which contains hot combustion products and one next to the floor which contains fresh air. The model predicts the motion of the interface separating these layers and the density of the hot layers as a function of time and an arbitrarily specified fire heat release rate.
Effect of diammonium phosphate on the flammability of wood and wood–polymethylmethacrylate composites
Authors: Kishore K. , Mohandas K. , Sagar D. Karuna
Published: May 2005

The effect of diammonium phosphate has been examined on sawdust–polymethylmethacrylate composites. It has been observed that the char formation depends on the distribution of DAP in sawdust and polymethylmethacrylate. An interesting correlation was found between the mass burning rates of the composites and the extent of char formation during thermal degradation.
Flame lengths under ceilings
Authors: Babrauskas Vytenis
Published: May 2005

The evaluation of hazards from developing room fires often requires a knowledge of flame lengths developed by burning objects. Procedures for estimating flame lengths have been available only for vertical plume fires, where there is no flame impingement on the room ceiling. Calculational procedures are developed for approximate calculation of flame lengths when part of the flame flow is along the ceiling. Four common geometries are treated: unbounded ceiling, plume near corner, plume in corner and one‐directional corridor spread. Ceiling flame lengths are calculated by use of the assumption that the total air entrained up to the flame tip is the same for ceiling flow as for the free fire. Comparison with limited experimental data suggests potential for prediction in full‐scale room fires.
Australian fire tests in standards and regulations
Authors: Martin K. G. , Dowling V. P.
Published: May 2005

Fire test methods cited in Australian regulations codes and specifications and the authorities promulgating them are reviewed. The pertinent regulations are generally drafted and administered by departments of the seven State governments, in some cases in reference to model codes developed by committees supported by the federal government to promote uniformity. The test methods, specifications and codes of practice are standardized by the Standards Association of Australia, an independent body with no statutory powers: the standards become mandatory when called up in legislation. Building materials and structures, consumer products, certain electrical components and children's nightwear are the main areas concerned with regulations that invoke fire test methods. The intent of the regulations and the test methods are discussed with particular emphasis on matters unique to Australia.
Testing products and materials for their contribution to flashover in rooms
Authors: Thomas P. H.
Published: May 2005

The first part of the paper describes briefly the calculation of the rate of heat release required to cause flashover in a compartment. It is possible from theory to suggest that the thermal feedback which controls the supply of gaseous fuel from a given area of combustibles may be generally less important than that which controls the extension of the area, although eigher can cause the rapid transition of flashover in the absence of the other. In the second part of the paper some implications for the testing of products and linings are explored and some suggestions are made for the way in which test data can be used to predict the behaviour of fires in rooms. Suggestions are made for the way in which test data can be used to predict the behaviour of fires in rooms. Suggestions are made for the development of test having a more direct meaning, in terms of both hazard and quantitative theory.
The thermal decomposition of polyurethanes and polyisocyanurates
Authors: Chambers John , Jiricny Josef , Reese Colin B.
Published: May 2005

The thermal decomposition of a number of TDI‐ and MDI‐based biscarbamates (model compounds for polyurethane foams) between 200°C and 1000°C showed that the urethane linkage undergoes an O‐acyl fission at about 300°C to generate the free isocyanate and alcohol. In the case of the flexible foam analogues, the newly generated TDI reacts further to generate volatile polyureas, termed ‘yellow smoke’. The MDI residues generated in the decomposition of a rigid foams react to yield non‐volatile polycarbodiimides. Both the yellow smokes and the polycarbodiimides decompose above 600°C to give a mixture of nitriles (including HCN) as well as a number of olefinic and aromatic compounds. The use of 13C labeling indicated that HCN and all the other nitriles generated during the high temperature decompositions originate in the thermal fission of the aromatic ring, the nitrile carbon being the 2‐, 4‐ or 6‐ carbon of MDI.
Determination of carbon monoxide in thermal degradation products of polymeric materials
Authors: Michal Jan
Published: May 2005

Gas chromatography using a column with a molecular sieve was applied to the determination of carbon monoxide in thermal degradation of polymeric materials. Attention was paid to the variance of individual determinations and conclusions were drawn regarding reproducibility of the processes studies. The carbon monoxide content in pyrolysis and thermooxidation products of the commonest polymeric materials and the effect of temperature on the amount of carbon monoxide formed were determined.
Estimation of the magnitude and spatial distribution of combustible materials in urban areas. A case study of the San Jose area, California
Authors: Simonett David S. , Barrett Thomas N. , Gopal Sucharita , Holsmuller Frank J. , Veregin Howard
Published: May 2005

This paper describes a methodology for estimating the magnitude and spatial distribution of urban fuel loadings using San Jose, California, as a case study. The study was undertaken to provide basic inputs into the modeling of large urban fires ignited by nuclear explosions, which has important implications for studies of the global climatic effects of nuclear war, or the so‐called ‘nuclear winter’ phenomenon. The methodology is based on the measurement of the numbers and sizes of different building occupancy types from aerial photographs for approximately 6000 1000‐ft (304.8‐m) grid cells covering the study area. These measurements were combined with literature‐derived average fuel loadings for each building type to yield the total fuel loading per cell. The total fuel loading thus calculated is approximately 4558.56 × 106 kg, yielding an average of 8.4 kg m−2 (1.7 lb ft−2) for the built‐up area of the city and 9.4 kg m−2 (1.9 lb ft−2) if unoccupied cells (i.e. cells containing no fuel) within the built‐up area are excluded. These figures are lower than previously published average values, due to the low‐density character of San Jose and the exclusion of certain components of total fuel loading by the methodology.
Iron‐containing compounds as flame retarding/smoke‐suppressing additives for PVC
Authors: Carty P. , Docherty A.
Published: May 2005

The incorporation of a range of iron‐containing inorganic and organometallic compounds into a semi‐rigid PVC formulation has been investigated. Limiting Oxygen Index and Smoke Density data were obtained across a wide range of formulations and the effects of the compounds on flammability and smoke generation are discussed. Iron‐containing inorganic compounds appear to have little effect on the flammability of semi‐rigid PVC but several of the organoiron compounds and iron oxides markedly reduce smoke formation.
Hot‐surface ignition temperatures of dust layers
Authors: Miron Yael , Lazzara Charles P.
Published: May 2005

Minimum dust layer ignition temperatures on a hot surface were determined for several dusts, using a test procedure recommended by the National Academy of Sciences. The dusts included coal, three oil shales, lycopodium spores, corn starch, grain and brass powder. For a few of the dusts the effects of particle size and layer thickness on the minimum ignition temperatures were examined. Test results were repeatable and reliable for the fuels, the lycopodium and the brass powder. The minimum hot‐surface ignition temperatures of 12.7‐mm thick layers of these dusts ranged from 160°C for brass to 290°C for 20‐gal ton−1oil shale. Flaming combustion was observed only with the brass powder. The minimum ignition temperatures decreased with thicker layers and with smaller particle sizes. Some difficulties were encountered with the corn starch and grain dusts. During heating, the starch charred and expanded; the grain dust swelled and distorted. The test was found acceptable for the purpose of determining the minimum layer ignition temperature of a variety of dusts. To prevent fire hazards due to smoldering or flaming dust layers the temperatures of surfaces on which combustible dusts accumulate should be lower than the minimum hot‐surface ignition temperatures of the dusts.
Estimation of flash point
Authors: Patil G. S.
Published: May 2005

A general correlation has been obtained for estimation of closed‐cup flash point of organic compounds from their normal boiling points. Estimated flash points are within a deviation of about 10% of reported values. However, separate correlations have been obtained and recommended for acids and alcohols for estimation of flash points for more accurate results.
Theoretical estimation of critical fire load close to an unprotected steel member
Authors: Keski‐Rahkonen O.
Published: May 2005

A theoretical model is set up to estimate critical fire loads close to unprotected steel members in large rooms. The members are assumed to have a critical temperature calculated from external loads. A constant fraction of the energy of the fire load is assumed to be absorbed by steel during burning. Rapid overall and zone burning with constant velocity are shown to yield the same critical fire load. Therefore it is concluded that these loads also give conservative estimates for the critical load in a real fire, the development of which lies between these two extremes. A general form of calculation is given. For rough estimates, 5% mass of the fire load as compared to the steel mass could be allowed.
Oxygen index and minimum limiting rates of polymer combustion
Authors: Zhubanov T. B. , Gibov K. M.
Published: May 2005

The influence of the initial temperature and thermal loss upon the oxygen index and burning rates of polymethylmethacrylate (PMMA), polystyrene (PS) and polyoxymethylene (POM) has been studied. It has been shown that the temperature profiles in the proximity of the burning surface are identical under the critical conditions for each of the polymers. Direct measurements of flame–polymer heat flows have shown that with an increase in initial temperature from 25° up to 200°C the heat flow decreases approximately by a factor of 2. An analogous situation is also observed with change in the thermal loss value in the condensed phase. These data are confirmed by linear pyrolysis experiments. In all experiments under critical conditions the oxygen concentration indicates the constant mass decomposition rate for each polymer. With a decrease in the outlet velocity of the combustibles below this value, which is specific to each polymer, extinction occurs.