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Solid-state reactions between sodium hydride and sodium hydroxide are unusual among hydride-hydroxide systems since hydrogen can be stored reversibly. In order to understand the relationship between hydrogen uptake/release properties and phase/structure evolution, the dehydrogenation and hydrogenation behavior of the Na-O-H system has been investigated in detail both ex- and in-situ. Simultaneous thermogravimetric-differential thermal analysis coupled to mass spectrometry (TG-DTA-MS) experiments of NaH-NaOH composites reveal two principal features: Firstly, an H2 desorption event occurring between 240 and 380 °C and secondly an additional endothermic process at around 170 °C with no associated weight change. In-situ high-resolution synchrotron powder X-ray diffraction showed that NaOH appears to form a solid solution with NaH yielding a new cubic complex hydride phase below 200 °C. The Na-H-OH phase persists up to the maximum temperature of the in-situ diffraction experiment shortly before dehydrogenation occurs. The present work suggests that not only is the inter-phase synergic interaction of protic hydrogen (in NaOH) and hydridic hydrogen (in NaH) important in the dehydrogenation mechanism, but that also an intra-phase Hδ+… Hδ– interaction may be a crucial step in the desorption process.  相似文献   
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Slipped capital femoral epiphysis is the most common hip pathology in children aged 8–15 years old. Research has shown that when a nonorthopedic provider evaluates this patient population, there can be a significant delay in the appropriate treatment, which may have serious consequences for the prognosis of the patient. The delays are often caused by the practitioner's inability to put the clinical picture into focus with regard to how these patients typically present.. This article presents the demographics, clinical presentation, differential diagnosis, radiological and physical examination techniques, and prevention strategies to recognize this condition and provide early intervention.  相似文献   
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Dermatophyte infections are exceedingly rare in neonates, possibly due to the thin stratum corneum and high sebum content of neonatal skin. Only a handful of cases of tinea faciei have been reported in neonates, with the majority of reports occuring in India. Here, we report what to our knowledge is the earliest reported presentation of tinea faciei in the United States. We also provide a brief literature review of other reported cases of tinea faciei in neonates less than 30 days of age.  相似文献   
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Same-sex marriage is a widely debated issue, including in Australia. This study used an online anonymous survey, with free-text responses, to investigate romantic and sexual relationships among Australian gay and bisexual men. We sought to identify what proportion of such men intended to marry their primary regular partner if marriage was made legally available to same-sex couples in Australia, as well as factors associated with intention or non-intention to marry. Most men in the sample did not intend to marry their primary regular partner. Even among men who considered themselves to be in a ‘relationship’ with their primary regular partner, less than half intended to marry him. However, many men who would not marry their current primary regular partner agreed that same-sex marriage should be available for gay and bisexual men in Australia. Reasons for intention to marry included a desire for social and legal equality, and ideas about marriage as a rite of passage, an expression of love and the most valued form of relationship in Australia. Those who did not intend to marry their primary regular partner offered a number of reasons, including that the nature of their relationship was incompatible with marriage, and reported a critical position towards marriage as a heteronormative institution.  相似文献   
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