bluuebunny/crossref_metadata_2025_split huggingface dataset:
The influence of antimony trihalides on flammability and ignitability of polyethylene
Authors: Yang J. P. , Brewer D. G. , Venart J. E. S. 
Published: May 2005

AbstractThe flammability and ignitability of polyethylene using antimony trihalide compounds as fire retardants was evaluated by standard methods to determine retardant effectiveness. Compared with other retardants, the antimony trihalide compounds, antimony tribromide and antimony trichloride, substantially reduced both the flammability and the ignitability of the polyethylene. The influence of retardant concentration, heat flux and type of polyethylene was also studied.
Note: Differential thermal analysis and limiting oxygen index of papyrus and its treatment with fire retardants
Authors: Abdel‐Hamid H. , El‐Engibawy A. , El‐Ashry E. S. H. , Khairy A. 
Published: May 2005

AbstractThe thermal behaviour of cellulose obtained from both the pith and rind of papyrus was studied and the flammability properties of paper produced from papyrus and other papers were measured. The use of flame retardants did not significantly alter the flammability properties of the papyrus paper.
Temperature distribution in a nailed gypsum‐stud joint exposed to fire
Authors: Fuller James J. , Leichti Robert J. , White Robert H. 
Published: May 2005

AbstractPerformance of wood‐stud walls depends on the integrity of nailed connections between the sheathing and the framing members. The performance of nailed connections has been studied at room temperature, but the effects of intense thermal loads, such as those from fire, are still poorly understood. This study examines the temperature distribution within nailed joints exposed to fire; this information is essential in modeling strength and stiffness of connections in wall systems. The finite‐element method was used to determine the effects of wood density, nail size, and type of gypsum board on temperature distribution within a set of connections. Temperature distributions were verified in nailed joints exposed in fire tests conducted in accordance with ASTM E119‐88. The principal path of heat flow through the connection was along the nail, rather than directly through the interface between gypsum board and wood. Wood species, type of gypsum board, and nail length did not change temperature distribution significantly.
Evaluation of the fire‐retardant properties of zinc hydroxystannate and antimony trioxide in halogenated polyester resins using the Cone Calorimeter method
Authors: Cusack P. A. 
Published: May 2005

AbstractAn investigation of the burning behaviour of a series of halogenated polyester resin formulations has been carried out using the Cone Calorimeter technique. The data obtained clearly indicate that zinc hydroxystannate (ZHS) is more effective than antimony trioxide (Sb2O3) in reducing the average and peak rates of heat release in a chlorinated resin and in decreasing the peak rate of heat release in a brominated resin. The decreases in average heat release rate in the brominated resin are similar for ZHS and Sb2O3. Hence, at an addition level of 2 phr (parts per hundred of resin), ZHS reduces the average heat release rates of a chlorinated and a brominated resin by 41% and 26%, respectively, and the peak heat release rates of the same resins by 38% and 39%, respectively. The degree of smoke suppression exhibited by ZHS in these Cone experiments is significantly greater than that given by Sb2O3. In general, the correlation between Cone Calorimeter data and results obtained using other laboratory fire tests (UL‐94, LOI) is poor, except in the case of smoke density measurements, where the correlation with NBS Smoke Box data is remarkably good. No correlation is observed between the measured values of CO and CO2 output by different test methods, although it is now generally considered that small‐scale fire tests cannot be used to predict gaseous concentrations in real‐fire situations.
Communication: Retainer frame effects on Cone calorimeter results for building products
Authors: Tsantaridis Lazaros , Östman Birgit 
Published: May 2005

AbstractThe Cone Calorimeter has been used for fire testing of different products on a small scale for almost a decade. However, the number of users has been increasing in the last two to three years. More experimentation with the apparatus has led to practical questions. One of these is about the use of a retainer frame which has been used mainly for building products, but very few direct comparisons have been presented.
Combustion behaviour of polyurethane flexible foams under Cone Calorimetry test conditions
Authors: Vanspeybroeck R. , Van Hees P. , Vandevelde P. 
Published: May 2005

AbstractThe first part of this study focuses on the effect of cone calorimeter test variables on polyurethane flexible foam properties such as ignitability, heat release rate, effective heat of combustion and mass loss. Three of the main commercial foam types were used, i.e. conventional slabstock foams, high‐resilience slabstock foams and all‐MDI (methylene diphenyldiisocyanate) moulded foams. A decrease in heat flux (down to 40%) with increasing distance from the conical heater was measured. As a consequence, results were found to depend to a large extent on the thickness and the melting behaviour of the foam samples. To achieve a sufficiently constant and uniform heat flux exposure, sample thickness had to be limited to 25 mm. In addition, repeatability was found to be good under various conditions, with percentage standard deviations for effective heat of combustion, peak rate of heat release and mass loss below 10%. Levels of radiant flux above 25 kW m−2 were found to be very severe to test flexible polyurethane foams. Under such conditions, foams that show large differences in combustion performance in small‐scale flammability tests performed almost identically in the cone calorimeter. In the second part of this study the effects of foam variables, such as foam type, density and melamine content, are defined. These effects were clearly pronounced at radiant flux levels of 15–25 kWm−2. Density was found to be the key variable in controlling ignition resistance. In addition, high‐resilience slabstock foams and all‐MDI moulded foams performed better than conventional slabstock foams of the same density. Melamine addition resulted in a delay of ignition for all three foam types and an incomplete combustion, decreased heat release and effective heat of combustion in HR‐slabstock and all MDI moulded foams. However, melamine is not effective as a heat sink in conventional slabstock foams. The different performance of the foam types under study can be explained by a different melting behaviour.
Comparison of Nordtest FIRE 007, CEN draft proposal (Radiant Panel) and Cone Calorimeter methods in the fire testing of floor coverings
Authors: Tomann Johanna 
Published: May 2005

AbstractDifferent types of floor coverings were tested using three different methods: the Cone Calorimeter (ISO 5660), the Nordtest floor covering test NT FIRE 007 and the German Radiant Panel Method (DIN 4102 Teil 14). The results of the comparisons between both flame spread and smoke production are given. Some correlation is found between the results of the Cone Calorimeter and the NT FIRE 007. Between other methods, no correlations seem to exist.
Surface temperature measurements on burning wood specimens in the Cone Calorimeter and the effect of grain orientation
Authors: Urbas Jože , Parker William J. 
Published: May 2005

AbstractSurface temperatures were measured on dry Douglas fir sapwood specimens during Cone Calorimeter tests using thermocouples and an infra‐red pyrometer. Good agreement between the thermocouples and the pyrometer was obtained when (1) the emissivity was assumed to be 1.0 and (2) the thermocouples were in good contact with the surface and were not located in the proximity of a fissure. The major fissures were normal to the grain of the wood and the volatiles vented through the fissures. Char oxidation in the region between the vertical fissures resulted in higher surface temperatures.
Sensitivity of the Room/Corner test to variations in the test system and product properties
Authors: Kokkala Matti A. 
Published: May 2005

AbstractThe effects of variations in the ISO 9705 Room/Corner Test equipment and product properties are discussed. Previous experimental results are reviewed and some new results from the EUREFIC fire research programme are reported. The effects considered include the room dimensions, the burner size, the heat output of the burner and the stand‐off distance of the burner. The error in the measured peak rate of heat release caused by the finite response time of the oxygen consumption calorimeter due to mixing of the exhaust gases is analyzed in detail. The effect of material properties determined with the cone calorimeter are evaluated by employing models simulating the Room/Corner Test.
An Intermediate‐Scale Calorimeter for building materials and assemblies
Authors: Shaw James R. , Urbas Joe 
Published: May 2005

AbstractA new Intermediate Scale Heat Release Rate Test Method is being developed primarily for testing assemblies in the vertical mode. Using the oxygen consumption calorimetry methodology and exhaust collection systems that already exist in many laboratories in the US and around the world, the apparatus is very economical to install. The sample size lends itself to reptitive testing in a short period of time. Sample preparation is generally quick and easy. Further development of the method should progress now that the method has been introduced at ASTM and will be introduced formally into ISO in the near future. There has been a favorable response by several laboratories who are considering construction of the apparatus. Additional assemblies tests are already underway and additional data will be presented in the near future.
A new bioactive bone cement: Its histological and mechanical characterization
Authors: Nishimura Naomi , Yamamuro Takao , Taguchi Yasushi , Ikenaga Minoru , Nakamura Takashi , Kokubo Tadashi , Yoshihara Satoru 
Published: May 2005

AbstractWe have developed a bioactive bone cement using CaOSiO2P2O5CaF2 glass powders and ammonium phosphate solution, and investigaed ist histological and mechanical characteristics in vivo. A bone defect was drilled in the proximal metaphysis of the rat tibia and filled with the bioactive bone cement in paste form or polymethylmethacrylate (PMMA) bone cement in the dough state. The cements were allowed to harden in situ. Histological examinationdemonstrated direct bonding between the new cement and bone by 4 weeks. The bioactive bone cement did not degrade up to 24 weeks postimplantation. The inflammatory reaction to the bioactive bone cement was less intense than the reaction induced by PMMA. Changes in the mechanical properties of the cement in vivo were studied by implanting hardened cylindrical specimens of both types of cement into the hindlimb muscles of ras of rats for 12 weeks. The compressive strength of the bioactive cement increased significantly after implantation, and reached 68 MPa in 1 week and 73 MPa in 4 weeks. These values were comparable to those of PMMA, and were maintained up to 12 weeks after implantation. This bioacive bone cement hadens in situ within a few minutes with negligible rise of temperature and can be easily handled as a paste for filling bone cavities of different shapes. In addition, this cement has good osteoconductive and bone bonding potential and fairly high mechanical strength. Therefore, this new cement could be used both as a bioactive bone cement and bone defect filler.
Collagen‐immobilized hydrogel as material for lamellar keratoplasty
Authors: Kobayashi Hisatoshi , Ikada Yoshito , Moritera Takeshi , Ogura Yuichiro , Honda Yoshihito 
Published: May 2005

AbstractA transparent poly(vinyl alcohol) hydrogel disc covalently immobilized with Type I collagen, fibronectin, and an adhesive oligopeptide and preseeded with corneal epithelial cells was implanted in rabbit cornea using a technique of lamellar keratoplasty, and the tissue response was studied by light and electron microscopy. Covalent immobilization of type I colagen on the surfaceof hydrogel was found to support growth and adhesion of the corneal epithelium in vitro. the in vivo experiment showed that cell seeding could prevant infection of the hydrogel. However, the implanted disc was rejected from the host cornea by epithelial downgrowth and the exchange between the seeded cells and host corneal epithelia was not observed until 14 days after surgery. The rejection might have occurred because of unsatisfactory fixation of the hydrogel to the host cornea.
The theory of scaling up laboratory data for the sedimentation type centrifuge
Authors: Ambler Charles M. 
Published: May 2005

AbstractThe mathematical theory of the sedimentation type of centrifuge is developed in terms of unhindered settling of a single particle that has reached equilibrium velocity. From this is derived the sigma value for several of the different forms of sedimentation type centrifuge which is the calculated equivalent area of a settling tank theoretically capable of doing the same amount of work in a unit gravitational field. The limitations controlling the accuracy of scale up between centrifuges of similar geometry and between centrifuges of substantially different geometry are discussed.
Control of foam during fermentation by the application of ultrasonic energy
Authors: Dorsey Arthur E. 
Published: May 2005

AbstractAn ultrasonic generator was tested at 3 frequencies for its effects on Serratia marcescens during fermentation. The generator controlled foam adequately at 26, 29, and 34 kc/sec at medium aeration rates up to 0·6 ft3/min. Final viable counts were in the same range as those for cultures grown using lard oil as a foam control agent. At 34 kc/sec the final viable counts were slightly higher than those of cultures with lard oil.No harmful effects were evident when large volumes of cultures were exposed to ultrasonic energy during growth.
Electronic computer solution for the MPN equation used in the determination of bacterial populations
Authors: Norman R. L. , Kempe L. L. 
Published: May 2005

AbstractThe utility and the practical precision of the Most Probable Number method for determining bacterial populations is currently restricted by a lack of adequate tables of solved examples or alternatively by an easy and quick solution to individual problems. Where an electronic computer is available, these restrictions need not apply. A computer programme and example solution for tabulated data and individual problems are presented in this paper.
Studies on large‐scale methods for propagation of animal cells
Authors: Rightsel Wilton A. , McCalpin Helen , McLean I. William 
Published: May 2005

AbstractA new strain of cells, designated as PD–MEK–I, and derived from the kidneys of a rhesus monkey embryo, has been isolated and utilized as a prototype for mass propagation in suspended cell cultures, using techniques similar to those developed for antiobiotic fermentations. The use of the large‐volume units for cultivation of tissue cells has been applied. These units are useful for preparing masses of cells for studies of cellular antigens, virus assays, antitumour cytotoxicity studies, and other biologically active materials, as well as seed for continuing cultures. In addition, other methods of roller bottle cultures, shaker flask cultures, spinner cultures, and disposable 1‐litre prescription bottles, have been modified so that over 35 different human and animal cell lines are being maintained in continuous culture. Any one of these procedures may be modified for preparing and handling large numbers of replicate cultures as well as for maintaining stock seed cultures. The characteristics of growth of cells utilizing these methods are similar to those encountered in microbial populations and the principles of antibiotic fermentation have been applied appropriately.
Analytical control of the biological oxidation in the production of Δ1,4‐androstadiene‐3,17‐dione
Authors: Mizsei Antal , Szabó Antal 
Published: May 2005

AbstractA rapid method for the assay of Δ1,4‐androstadiene‐3, 17‐dione has been worked out for use in the control of its production by biological oxidation. The method consists of a single selective extraction step, a specific colour reaction and a photometric measurement. Based upon the analyses of samples taken at frequent intervals, the oxidative process can be stopped at its optimum production level. Thus insufficient transformation and over‐oxidation can both be avoided. The time needed for one analysis is 20 minutes.
Spray‐drying of tomato puree, groundnut and soyabean proteins and sugar–gelatine solutions
Authors: Evans G. 
Published: May 2005

AbstractTomato puree, groundnut and soya protein, and sugar‐gelatine solutions were successfully dried in a Scott pilot plant spray‐drier. The tomato puree did not need the addition of a carrier provided that the air plenum of the drier was suitably modified. Spray‐drying did not change the colour of tomato puree and the protein solutions, the viscosity characteristics of the protein solutions, or the nutritive value of the proteins. The conditions for the successful spray‐drying of sugar‐gelatine solutions were rather critical. The temperature in the spray‐drier had the major effect on the quality of the powders. Published data on spray‐drying do not provide a basis for predicting the drying behaviour of different products; experiments on the plant are essential.
Ion‐exchange chromatography of the streptomycin complex
Authors: Pereira J. N. 
Published: May 2005

AbstractVarious studies have revealed the presence of several maltolproducing compounds in streptomycin preparations. These previous studies have utilized the techniques of counter‐current distribution, column chromatography, paper chromatography, and electrophoresis. A system of cation‐exchange chromatography has been reported which separates, at least partially, six components of the streptomycin complex. This technique involves the use of a gradient elution procedure.In addition to five maltol‐producing compounds, another member of the complex is reported. The possible significance of such a compound is discussed.
Redox potential changes in the 2‐keto‐L‐gulonic acid fermentation—I. Correlation between redox potential and dissolved‐oxygen concentration
Authors: Tengerdy Robert P. 
Published: May 2005

AbstractThe redox potential changes in the oxidative fermentation of L‐sorbose to 2‐keto‐L‐gulonic acid were investigated, using a mutant strain of Pseudomonas. The growth medium contained sorbose as the sole carbohydrate source. It was found that the redox potential curve of the fermenting system indicated qualitatively the existing oxygen demand of the culture. Increasing aeration rates led to higher oxygen demand and lower redox potentials. A comparison of the redox potential curves revealed that although the amount of dissolved oxygen directly affected the respiration of the culture, it did not necessarily mean respiratory insufficiency. The redox potential difference between the aerated and the deoxygenated (nitrogen flushed) fermentation broth was found to be linearly proportional to the logarithm of the dissolved‐oxygen concentration. This observation served as the basis of a new quantitative method of dissolved‐oxygen measurement, for which the name differential redoxymetry was proposed.
Redox potential changes in the 2‐keto‐L‐gulonic acid fermentation—II. Relationship between redox potential and product formation
Authors: Tengerdy Robert P. 
Published: May 2005

AbstractIn the investigation of the redox potential changes of the oxidative fermentation of L‐sorbose to 2‐keto‐L‐gulonic acid, it was found that the 2‐keto‐L‐gulonic acid formation proceeded favourably at low negative redox potential values. Low redox potentials were maintained in a continuous fermentation process in the chemostat, with a resulting high 2‐keto‐L‐gulonic acid formation rate. L‐Tyrosine and some of its analogues stimulated the 2‐keto‐L‐gulonic acid formation. The stimulation seemed to be bound to low redox potential values, and suggested the action of a direct oxidase‐type enzyme.
Interaction of growth factors during progression towards steroid independence in T‐47‐D human breast cancer cells
Authors: Daly Roger J. , King Roger J. B. , Darbre Philippa D. 
Published: May 2005

AbstractWhen deprived of steroid in the long term, T‐47‐D human breast cancer cells lose estrogen sensitivity of cell growth. This loss of response results from an increased basal growth rate in the absence of steroid, not from a loss of estrogen‐simulated growth, and it occurs without any loss of estrogen receptor number or function. Growth factor gene expression and sensitivity have been investigated in this model system in an attempt to unravel the molecular mechanisms underlying the progression to steroid autonomy. The transition was accompanied by a decreased dependence on added serum and by a loss of the stimulatory effects of insulin and basic fibroblast growth factor, but also by an acquired sensitivity to stimulation by transforming growth factor‐β (TGF‐β). An increase in TGF‐β mRNA was detected following loss of steroid sensitivity. There was no increase in epidermal growth factor (EGF) receptor number. These findings are discussed in relation to current knowledge concerning the mechanisms by which estrogens stimulate breast cancer cell proliferation.
Inhibition of phosphorylation of cellular dUTP nucleotidohydrolase as a consequence of herpes simplex virus infection
Authors: Lirette Ronald , Caradonna Sal 
Published: May 2005

AbstractDuring an infection with herpes simplex virus, activity of cellular dUTPase decreases as a function of time, post‐infection, while virus‐encoded dUTPase activity increases. Prelabeling of cells with 35S‐methionine and immunoprecipitation analysis, using monoclonal antibodies, indicates that cellular dUTPase protein levels remain the same (with respect to levels in uninfected cells) throughout the infection period. New synthesis of cellular dUTPase does not occur in infected cells as determined by 35S‐methionine labeling during infection.Further characterization of the cellular dUTPase, in uninfected cells, reveals that the protein is post‐translationally phosphorylated at serine residues. Pulse labeling of virus‐infected cells with 32P‐orthophosphate reveals that the phosphorylation rate of the cellular dUTPase protein decreases significantly as a function of time post‐infection. In an effort to establish that phosphate turnover was occurring on the cellular dUTPase protein, cells were prelabeled with 32P‐orthophosphate and then infected with HSV in the absence of label. Evidence from this experiment indicates that the phosphate moiety is removed from the cellular dUTPase protein during the infection.A series of viable virus mutants was generated by insertional inactivation of the HSV dUTPase gene. These mutants do not express viral dUTPase activity and HSV dUTPase protein is not detected by western blot analysis. However, in contrast to the wild‐type situation, these mutant virus retain significant cellular dUTPase activity throughout infection. Interestingly, phosphorylation of cellular dUTPase protein is now readily detectable in each of the mutant virus‐infected cells.These studies indicate that cellular dUTPase activity is diminished in wild‐type HSV‐infected cells by a process of dephosphorylation. It also appears that in mutant HSV, lacking the virus dUTPase, the mechanism of dephosphorylation and thus inactivation of cellular dUTPase is not functional. The end result is that the mutant virus can now rely on the cellular activity for its survival.