Evaluating Ionic Liquids as Hypergolic Fuels: Exploring Reactivity from Molecular Structure

International audienceA total of 38 ionic liquids (19 of which are new) comprised of 13 cations, 1-propargyl-3-methyl-imidazolium, 1-allyl-3-methyl-imidazolium, 1,3-dimethyl-imidazolium, 1-ethyl-3-methyl-imidazolium, 1-butyl-3-methyl-imidazolium, 1-methoxyethyl-3-methyl-imidazolium, 1-methyl-4-butyl-1,2,4-triazolium, 1-methyl-4-allyl-1,2,4-triazolium, 1-methyl-4-amino-1,2,4-triazolium, N-butyl-N-methyl-pyrrolidinium, N-allyl-N-methyl-pyrrolidinium, N-allyl-pyridinium, and N-butyl-3-methyl-pyridinium, paired with three anions, dicyanamide, azide, and nitrocyanamide, have been prepared, characterized, and evaluated as potential hypergolic fuels by determining key physical, thermal, and ignition properties. The reactivity of these ionic liquids (32 liquids and 6 solids which melt below 100 degrees C) was strongly correlated to increased electron density in the cation, while small changes in physical properties had little effect beyond a certain threshold, suggesting that subtle changes in chemical reactivity can greatly influence the hypergolic ignition pathway

Evaluating Ionic Liquids as Hypergolic Fuels: Exploring Reactivity from Molecular Structure

A total of 38 ionic liquids (19 of which are new) comprised of 13 cations, 1-propargyl-3-methyl-imidazolium, 1-allyl-3-methyl-imidazolium, 1,3-dimethyl-imidazolium, 1-ethyl-3-methyl-imidazolium, 1-butyl-3-methyl-imidazolium, 1-meth-oxyethyl-3-methyl-imidazolium, 1-methyl-4-butyl-1,2,4-triazolium, 1-methyl-4-allyl-1,2,4-triazolium, 1-methyl-4-amino-1,2,4-tri-azolium, <i>N</i>-butyl-<i>N</i>-methyl-pyrrolidinium, <i>N</i>-allyl-<i>N</i>-methyl-pyrrolidinium, <i>N</i>-allyl-pyridinium, and <i>N</i>-butyl-3-methyl-pyridinium, paired with three anions, dicyanamide, azide, and nitrocyanamide, have been prepared, characterized, and evaluated as potential hypergolic fuels by determining key physical, thermal, and ignition properties. The reactivity of these ionic liquids (32 liquids and 6 solids which melt below 100 °C) was strongly correlated to increased electron density in the cation, while small changes in physical properties had little effect beyond a certain threshold, suggesting that subtle changes in chemical reactivity can greatly influence the hypergolic ignition pathway

Evaluating Ionic Liquids as Hypergolic Fuels: Exploring Reactivity from Molecular Structure

A total of 38 ionic liquids (19 of which are new) comprised of 13 cations, 1-propargyl-3-methyl-imidazolium, 1-allyl-3-methyl-imidazolium, 1,3-dimethyl-imidazolium, 1-ethyl-3-methyl-imidazolium, 1-butyl-3-methyl-imidazolium, 1-meth-oxyethyl-3-methyl-imidazolium, 1-methyl-4-butyl-1,2,4-triazolium, 1-methyl-4-allyl-1,2,4-triazolium, 1-methyl-4-amino-1,2,4-tri-azolium, <i>N</i>-butyl-<i>N</i>-methyl-pyrrolidinium, <i>N</i>-allyl-<i>N</i>-methyl-pyrrolidinium, <i>N</i>-allyl-pyridinium, and <i>N</i>-butyl-3-methyl-pyridinium, paired with three anions, dicyanamide, azide, and nitrocyanamide, have been prepared, characterized, and evaluated as potential hypergolic fuels by determining key physical, thermal, and ignition properties. The reactivity of these ionic liquids (32 liquids and 6 solids which melt below 100 °C) was strongly correlated to increased electron density in the cation, while small changes in physical properties had little effect beyond a certain threshold, suggesting that subtle changes in chemical reactivity can greatly influence the hypergolic ignition pathway

Evaluating Ionic Liquids as Hypergolic Fuels: Exploring Reactivity from Molecular Structure

A total of 38 ionic liquids (19 of which are new) comprised of 13 cations, 1-propargyl-3-methyl-imidazolium, 1-allyl-3-methyl-imidazolium, 1,3-dimethyl-imidazolium, 1-ethyl-3-methyl-imidazolium, 1-butyl-3-methyl-imidazolium, 1-meth-oxyethyl-3-methyl-imidazolium, 1-methyl-4-butyl-1,2,4-triazolium, 1-methyl-4-allyl-1,2,4-triazolium, 1-methyl-4-amino-1,2,4-tri-azolium, <i>N</i>-butyl-<i>N</i>-methyl-pyrrolidinium, <i>N</i>-allyl-<i>N</i>-methyl-pyrrolidinium, <i>N</i>-allyl-pyridinium, and <i>N</i>-butyl-3-methyl-pyridinium, paired with three anions, dicyanamide, azide, and nitrocyanamide, have been prepared, characterized, and evaluated as potential hypergolic fuels by determining key physical, thermal, and ignition properties. The reactivity of these ionic liquids (32 liquids and 6 solids which melt below 100 °C) was strongly correlated to increased electron density in the cation, while small changes in physical properties had little effect beyond a certain threshold, suggesting that subtle changes in chemical reactivity can greatly influence the hypergolic ignition pathway

Distribution of plasma fatty acids is associated with response to chemotherapy in non-Hodgkin's lymphoma patients

Our recent data have linked plasma phospholipid fatty acid (FA) profile in patients with non-Hodgkin's lymphoma (NHL) with the clinical stage and aggressiveness of the disease. Thus, we proposed that plasma FA status in these patients may influence the effect of chemotherapy. The aim of this work was to assess FA status in NHL patients undergoing chemotherapy in relation to their response to therapy. We analyzed plasma FA profile in 47 newly diagnosed NHL patients before chemotherapy, after 3 cycles and after the end of the planned chemotherapy. Patients were treated according to the hospital protocol: 28 patients with cyclophosphamide, doxorubicin, vincristine and prednisone, 7 with other anthracycline-containing regimens, 4 patients with cyclophosphamide, vincristine and prednisone and 8 with fludarabine-based regimens. Rituximab was added in 22 patients. Ten patients who did not receive all planned chemotherapy due to death or toxicity (non-completers) had significantly lower (p lt 0.05) baseline proportion of palmitoleic, linoleic, eicosapentaenoic and docosahexaenoic acid, as well as n-3 and n-6 FA, than the patients who completed chemotherapy (completers). Furthermore, the completers were divided according to the response to chemotherapy to complete remission (CR), stable disease and progressive disease (PD). Proportion of palmitic acid after the end of chemotherapy was the highest in the PD group, while stearic acid showed the opposite trend. Palmitoleic acid and all n-3 FA (18: 3, 20: 5, 22: 5 and 22: 6) were the highest in the patients in remission and the lowest in PD (p lt 0.001). Linoleic acid decreased and arachidonic acid increased from the CR to the PD group (p lt 0.001). These results suggest that aberrations in plasma FA may influence response to chemotherapy in patients with NHL

Behavioral Deficits at 18-22 Months of Age Are Associated with Early Cerebellar Injury and Cognitive and Language Performance in Children Born Extremely Preterm

To investigate associations in toddlers born extremely preterm (<28 weeks) between neonatal neuroimaging and 18- to 22-month developmental and behavioral outcomes. Cohort analysis from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network Surfactant Positive Airway Pressure and Pulse Oximetry Trial Neuroimaging and Neurodevelopmental Outcomes Study of infants born extremely preterm. Subjects underwent cranial ultrasonography and near-term magnetic resonance imaging (MRI). At 18-22 months of corrected age, the assessment included the Brief Infant Toddler Social Emotional Assessment (BITSEA) Problem and Competence Scale scores and the Bayley Scales of Infant Development, Third Edition (Bayley-III). The BITSEA Problem Scale assesses dysregulation; the Competence Scale assesses social-emotional competence. We examined associations of Problem and Competence scores and positive screen rates with cranial ultrasonography and near-term MRI. Mean BITSEA and Bayley-III scores were compared using ANOVA and positive screen rates with the χ2 test. We computed correlations between BITSEA and Bayley-III scores. Of the 397 children, positive BITSEA screens were found in 34% for the Problem score and 26% for the Competence score. Presence of lesions on near-term MRI that included cerebellar lesions were significantly associated with lower BITSEA Competence but not with Problem scores; Competence scores were inversely related to the presence/significance of lesions. Positive screens on Competence scores and on both Competence and Problem scores were significantly associated with Bayley-III cognitive and language scores <85 (P < .001). Social–emotional competence contributes to deficits in cognitive and language development. Presence of injury on near-term MRI that includes cerebellar lesions is associated with later social–emotional competence and may be a useful predictor to guide early assessment and intervention. ClinicalTrials.gov: NCT00063063 and NCT00233324

Growth Rates of Infants Randomized to Continuous Positive Airway Pressure or Intubation After Extremely Preterm Birth.

Objective To evaluate the effects of early treatment with continuous positive airway pressure (CPAP) on nutritional intake and in-hospital growth rates of extremely preterm (EPT) infants. Study design EPT infants (240/7-276/7 weeks of gestation) enrolled in the Surfactant Positive Airway Pressure and Pulse Oximetry Trial (SUPPORT) were included. EPT infants who died before 36 weeks of postmenstrual age (PMA) were excluded. The growth rates from birth to 36 weeks of PMA and follow-up outcomes at 18-22 months corrected age of EPT infants randomized at birth to either early CPAP (intervention group) or early intubation for surfactant administration (control group) were analyzed. Results Growth data were analyzed for 810 of 1316 infants enrolled in SUPPORT (414 in the intervention group, 396 in the control group). The median gestational age was 26 weeks, and the mean birth weight was 839 g. Baseline characteristics, total nutritional intake, and in-hospital comorbidities were not significantly different between the 2 groups. In a regression model, growth rates between birth and 36 weeks of PMA, as well as growth rates during multiple intervals from birth to day 7, days 7-14, days 14-21, days 21-28, day 28 to 32 weeks PMA, and 32-36 weeks PMA did not differ between treatment groups. Independent of treatment group, higher growth rates from day 21 to day 28 were associated with a lower risk of having a Bayley-III cognitive score Conclusions EPT infants randomized to early CPAP did not have higher in-hospital growth rates than infants randomized to early intubation