Revisiting the Hydrogen Storage Behavior of the Na-O-H System

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 H^δ+… H^δ– interaction may be a crucial step in the desorption process.     

Caution! Overestimation of treatment effects of corticosteroid therapy for community-acquired pneumonia in a meta-analysis of randomized controlled trials

It is well known that a meta-analysis of randomized controlled trials aims to increase the power and precision of the estimated intervention effects. However, when a meta-analysis includes a limited number of patients and a small number of events, overestimation of intervention effect estimates may occur and could cause spurious results. Although many biases can cause the overestimation, random error may be the most common cause. Trial sequential analysis (TSA) can explore the independent effect of random error on intervention effect estimates in meta-analyses and protect meta-analyses against overestimation due to random error.     

微板紫外速率法漏检高值ALT标本一例

谷丙氨基转移酶（Alanine asninotrasferase，ALT）检测是采供血机构血液必检项目之一，ALT检测作为早期肝病诊断的一项非特异性指标，有助于鉴别与输血相关肝炎病毒携带者，同时可以在一定程度上弥补某些肝炎病毒标志物未被检测及“窗口期”的缺陷，有助于预防输血相关肝炎的传播。我血站实验室采用微板为载体的方法进行血清ALT检测：微板紫外速率法为初检方法；微板丙酮酸氧化酶法为复检方法。在检测过程中一例高值ALT血样，微板紫外速率法检测结果为6．6U／L，出现假阴性结果造成漏检，现报告如下：     

邹城市预防艾滋病健康教育效果评价

目的评价预防艾滋病健康教育与行为干预效果。方法采用问卷方式对社区居民进行预防艾滋病信息的可及性及知信行的调查。结果社区居民艾滋病知晓率为97.41%,熟悉艾滋病传播途径的87.78%,62.78%的认为艾滋病病人或感染者和正常人享有一样的入学/就业权,38.70%的人愿意与感染艾滋病的同事继续共事,60.19%的人愿意与感染艾滋病的家人继续共同生活,最近3次性行为100%使用安全套者为26.48%,82.04%的人有医疗用血安全意识,64.81%的人有医疗器械安全意识。最想获取艾滋病预防措施、传播途径、病理知识、症状表现、治疗方法、检测途径及检测方法、疫情信息,新闻、电视公益广告、专题报道、反映艾滋病病人生活的电影或电视剧、科普材料、大型公益演出人们最喜欢。结论政府重视,多部门合作,组织机构健全,宣传教育广泛,干预措施到位,成效显著。     

运用直观教学法提高学生对知识的感知

课堂讲授是高校班级授课的基本形式,在课堂讲授中起主导作用,占重要地位[1]。近年来随着高等护理教育的发展,越来越多的临床护士担任起了本科护理系的临床教学任务。而临床护士非专业教师,在教学过程中需要掌握一些教学方法与技巧,才能提高课堂讲授质量。心理学研究表明,直观是     

旋覆代赭汤合左金丸治疗反流性食管炎62例

反流性食管炎是内科常见病,单一的西药治疗副作用大,易复发,疗程长,患者十分痛苦。我院自2000年以来,采用中西医结合治疗本病,取得了较好的疗效,现总结如下。1一般资料124例患者均为门诊和住院病人,其中男68例,女56例。年龄20~76岁,平均42·3岁。病程2个月~10年,平均0·8年。有