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Taxonomy Of Thermopsis (Fabaceae) In North-America
Comprehensive reevaluation of both herbarium specimens and field observations of the North American Thermopsis leads to our recognition of 10 species. Three species occur in the southern Appalachians: T. villosa, T. mollis, and T. fraxinifolia. The Rocky Mountains and intermountain regions are populated by the relatively variable and widespread species T. divaricarpa, T. montana, and T. rhombifolia. The Pacific coastal mountains of California are dominated by the variable T. californica (with three infraspecific taxa), which gives way to T. gracilis in northern California and western Oregon. Thermopsis macrophylla and T. robusta have restricted ranges in California.Integrative Biolog
Method for preparing organic hyponitrites
Tertiary organic hyponitrite usable as initiators for polymerizing ethylenically unsaturated compounds are prepared by reacting an alkali metal, alkaline earth, ammonium or substituted ammonium salt of hyponitrite, such as sodium hyponitrite, with a tertiary organic halide, such as tert-butyl chloride, in the presence of one or more weak Friedel-Crafts catalysts, such as ferric or zinc chloride, and in a solution of a neutral solvent.https://digitalcommons.mtu.edu/patents/1117/thumbnail.jp
Space shuttle nonmetallic materials age life prediction
The chemiluminescence from samples of polybutadiene, Viton, Teflon, Silicone, PL 731 Adhesive, and SP 296 Boron-Epoxy composite was measured at temperatures from 25 to 150 C. Excellent correlations were obtained between chemiluminescence and temperature. These correlations serve to validate accelerated aging tests (at elevated temperatures) designed to predict service life at lower temperatures. In most cases, smooth or linear correlations were obtained between chemiluminescence and physical properties of purified polymer gums, including the tensile strength, viscosity, and loss tangent. The latter is a complex function of certain polymer properties. Data were obtained with far greater ease by the chemiluminescence technique than by the conventional methods of study. The chemiluminescence from the Teflon (Halon) samples was discovered to arise from trace amounts of impurities, which were undetectable by conventional, destructive analysis of the sample
Hydrocarbon fuel additives and method for preparing same
A compound having the general formula R*COH[- CORJj,, wherein R is a lower alkyl hydrocarbon radical, y is 0 or 1, and x is 2 when y is 1 and 3 when y is 0, is prepared by admixing carbon monoxide, a transition metal halide, and an organomonolithium compound or an anionic equivalent thereof.https://digitalcommons.mtu.edu/patents/1100/thumbnail.jp
Optical radiation from the interaction of energetic atoms, ions, electrons, and photons with surfaces
Heavy particle, electron, and UV photon bombardment of solid surfaces has been recently observed to result in the emission of infrared, visible, and ultraviolet radiation. This effect occurs over a wide range of incident projectile energies. Line radiation arising from transitions between discrete atomic or molecular levels may be attributed to the decay of excited particles which have been sputtered or electronically/chemically desorbed from the surface. Broadband continuum radiation, which is also observed, is believed to arise either from fluorescence of the near surface bulk or from the radiative decay of desorbed excited clusters. Spacecraft, in the ambient near Earth environment, are subject to such bombardment. The dynamics of energetic particle and photon beam interactions with surfaces which lead to surface erosion and glow phenomena will be treated. In addition, projected experimental and theoretical studies of oxygen and nitrogen beam surface interactions on materials characteristic of spacecraft surfaces will be discussed
Bilateral Extracranial Carotid Artery Aneurysms: A Rare Complication of Marfan Syndrome
Marfan Syndrome (MFS) is an autosomal dominant connective tissue disorder caused by a mutation in the FBN1 gene that encodes for the extracellular matrix protein fibrillin-1. The clinical manifestations of MFS which lead to morbidity and mortality are primarily those involving aortic disease, such as aneurysmal dilation, aortic regurgitation, and aortic dissection. Despite 60-80% of adults with MFS having some degree of aortic disease, carotid artery aneurysms are rare and usually represent extensions of aortic dissections.1 We report a 70-year-old female with a history of ectopia lentis and family history of MFS who presented to the ED with epistaxis and anemia. An arteriogram revealed an incidental finding of bilateral carotid artery aneurysms a rare phenomenon even in the presence of connective tissue disease. Review of the literature reveals very little data on the clinical presentation, treatment, and outcome of MFS patients with extracranial carotid artery aneurysms (ECAAs). We discuss presentation, etiology, and management options reported for these rare occurrences
Prolonged Dyspnea after Interscalene Block: Attributed to Undiagnosed Addison's Disease and Myasthenia Gravis
This report describes a patient who had a series of daily interscalene nerve blocks to treat pain following a shoulder manipulation for postsurgical stiffness. She experienced acute respiratory compromise that persisted for many weeks. All typical and unusual causes of these symptoms were ruled out. Her treating pulmonologist theorized that the ipsilateral carotid body had been injured. However, it was subsequently determined that the constellation of symptoms and their prolonged duration were best explained by a poor stress response from Addison's disease coupled with exacerbation of early onset myasthenia gravis. This patient's case is not a typical reaction to interscalene nerve blocks, and thus preoperative testing would not be recommended for myasthenia gravis or Addison's disease without underlying suspicion. We describe this report to inform physicians to consider a workup for these diagnoses if a typical workup rules out all usual causes of complications from an interscalene block
Chemiluminescence Study on Thermal Degradation of Aircraft Tire Elastomers
Since the autoxidative process accounts in part for the degradation of rubber, including aircraft tires, it was felt that a study of the chemiluminescence from unsaturated elastomers could contribute significantly to an understanding of the degradation mechanism. The study revealed similarities in chemiluminescence behavior between four elastomers which were investigated, and it shows that similar oxidation mechanisms occur. Oxidative chemiluminescence was observed from purified samples of cis-1,4-polybutadiene, cis-1,4-polyisoprene, trans-polypentenamer, and 1,2-polybutadiene in an oxygen atmosphere at 25-150 C. The elastomer samples were placed in a 600 watt oven which is equipped with gas inlets for introducing any desired atmosphere. Chemiluminescence emission from the samples was focused with a two inch quartz lens onto the detector of a 12" photomultiplier which is connected to a photon counter. A strip-chart recorder, connected to the counter, permitted automatic data collection. Diagrams of the apparatus are included. The chemical reactions which occurred from the thermal decomposition of the polymer samples are described, and results (and tabulated data) are discussed
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