Pyrolysis and combustion of cellulose. VII. Thermal analysis of the phosphorylation of cellulose and model carbohydrates during pyrolsis in the presence of aromatic phosphates and phosphoramides

Thermal gravimetric analysis, differential scanning calorimetry, and derivative thermal gravimetric analysis were utilized to characterize the thermal interactions between cellulose, 1-6, anhydro β-D-glucopyranoside, and D-glucose and model phosphate and phosphoramide flame retardants. The phosphoramides induced higher char yields than the phosphates during the pyrolysis of the mixtures of carbohydrates and organophosphorus compounds. Exothermic reactions attributed to phosphorylation and char formation were observed with each of the phosphoramide/carbohydrate mixtures and were absent with the phosphates. The individual phosphorus compounds studied showed similar thermal behavior with each of the carbohydrates indicating that the mode of interaction for these mixtures was similar. Isothermal gravimetric analysis of the organophosphorus/carbohydrate mixtures was used to measure the rate of decomposition weight loss from isothermal conditions. This weight loss was used as an indication of rate of fuel formation. The kinetics observed for these measurements indicated that the phosphoramide mixtures underwent a rapid weight loss to a final char with an effective E_act of about 55 kcal/mol while the phosphate mixtures exhibited effective E_act′s for decomposition lower than those observed for the pure carbohydrates. Mixtures of glucose with selcted arylphosphoramide esters were pyrolysed in order to determine the effect of lability of the leaving group on char formation. Gas chromatographic analysis of the pyrolysis products indicated that phenol was the favored leaving group in comparison with aniline units, but char promotion appeared to be dependent on the number of P-N bonds present in the original phosphoramide. Electron spectroscopy for chemical analysis indicated that chemically similar chars were obtained from the different organophosphorus/carbohydrate combinations.     

Morphological and orthographic similarity in visual word recognition.

The differential impact of orthographic and morphological relatedness on visual word recognition was investigated in a series of priming experiments in Dutch and German. With lexical decision and naming tasks, repetition priming and contiguous priming procedures, and masked and unmasked prime presentation, a pattern of results emerged with qualitative differences between the effects of morphological and form relatedness. With lexical decision, mere orthographic similarity between primes and targets (e.g., keller–KELLE, cellar–ladle) produced negative effects, whereas morphological relatedness (e.g., kellen–KELLE, ladles–ladle) consistently resulted in facilitation. With the naming task, positive priming effects were found for morphological as well as for mere form similarity. On the basis of these results, a model of the lexicon is proposed in which information about word form is represented separately from morphological structure and in which processing at the form level is characterized in terms of activation of, and competition between, form-related entries. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Test sequences in screening for breast cancer

Published data of Stark and Way on the screening of 2,684 women at high risk of breast cancer are analyzed to arrive at a preferred sequence of screening tests. In the practical situation where palpation first signals a problem, the analysis suggests thermography to follow. Women with positive thermograms should then be biopsied, and those with negative thermograms should be mammographed. A positive mammogram calls for biopsy, and a negative one calls for close follow-up. For high-risk women whose breasts appear normal on palpation, a subsequent negative thermogram is not definitive enough to terminate investigation, but a negative mammogram after a negative palpation is enough evidence to waive further investigation for some time. A positive mammogram calls for immediate biopsy in any circumstance.     

Serum IgE levels in paraproteinaemia

Serum IgE levels were measured by radioimmunoassay with a 'Phadesbas test kit' in 45 patients with multiple myeloma or macroglobulinaemia. As with other immunoglobulin classes, low serum levels of IgE were found.     

Pyrolyse von Maleins?urehydrazid und Hydrazin

Zusammenfasung Maleinsäurehydrazid (TIM) bzw. Hydrazin (H) warden im Quarzrohr pyrolysiert. Bei 900° C wird H völlig zersetzt, Hauptprodukt ist das Ammoniak. Bei niedrigeren Temperaturen blieb H z. T. unzersetzt. Unter den Pyrolyseprodukten (900° C) des MH konnte kein H nachgewiesen werden. Als Pyrolyseprodukte wurden aromatische Kohlenwasserstoffe, aliphatische und aromatische Nitrile und N-Heterocyclen nachgewiesen. Bei einer Pyrolysetemperatur von 650° C wurden 0,06% H (bezogen auf MH 30) gefunden. Durch Untersuchung des Rauches von Zigaretten, die mit H imprägniert waren, konnte gezeigt werden, daß H schnell zu Produkten wie Acetaldazin und Acetonitril reagiert.

---

Pyrolysis of maleic hydrazide and hydrazine

Summary Maleic-hydrazine (MH) and hydrazine (H) were pyrolyzed in quartz tubes. At 900° C H is completely decomposed, ammonia being the main product. At lower temperatures, H partly remained undecomposed. Among the pyrolysis products (900° C) of MH no quantities of H could be found. As pyrolysis products, aromatic hydrocarbons, aliphatic and aromatic nitriles and heterocycles were detected. At pyrolysis temperatures of 650° C, 0,06% H were found (related to MH 30). By investigation of cigarette smoke impregnated by H, it could be demonstrated that H quickly reacts to products like acetaldazine and acetonitrile.