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91.
消除铸件铸造应力的退火工艺过程讨论   总被引:1,自引:0,他引:1  
铸件脱模后,必须经过退火才能投入使用或进入后续工序。本文对铸件退火时如何控制加热速度、保温时间、冷却速度进行了充分的研究和探讨,为合理制定铸件退火工艺指出了方向。  相似文献   
92.
Abstract

Previous research on school experiences has often focused on lesbian and gay students. Far fewer studies have examined trans* students’ experiences, especially with respect to community support. And none of this work has addressed relevant issues in an East Asian Chinese cultural context, where transgender equality has been a hotly debated issue in recent years, and prejudice towards members of this ‘invisible’ population still persists. This paper highlights the school experiences of trans* students based on a literature review of international, regional and Hong Kong publications. A case study analysis of one Hong Kong community support programme is used as an example to highlight the important role that this kind of work can play in filling a gap left by the formal education sector. Findings suggest that, given the influence of genderism and deficiencies of in school environments, community support services provided by non-government organisations can play a significant role not only in raising public awareness, but also in filling education and service gaps for sexual and gender minority students.  相似文献   
93.
粘结层性能是影响外贴FRP结构加固效果的重要因素。本文介绍了外贴FRP结构粘结剪应力分析的主要理论和所取得成果。重点对粘结剪应力分析发展现状进行了综述,并对外贴FRP加固结构及剪应力研究发展趋势进行了展望。  相似文献   
94.
Mercury pollution and acute neurotoxicity of mercury is well known. The recent reports suggest the adverse effect of low dose mercury, though the available literature is still silent on its mechanism. This study was therefore undertaken to probe the effect of low dose methyl mercury induced heavy metal toxicity on free radical stress and its impact on behaviour of male albino rats. Male albino rats were exposed to 1 mg/kg body wt of methylmercury chloride for seven days, on day 8 they were tested for motor and memory functions. They were sacrificed later for biochemical estimations for rate of lipid peroxidation, nucleic acids, proteins in cerebrum, cerebellum and brain stem. There was an increase in the rate of lipid peroxidation showing methyl mercury induced free radical stress. The motor and memory functions demonstrated a clear decline, besides there was a lowering in the levels of nucleic acids and proteins as compared to controls. The results are important in view of recent reports that methyl mercury induced free radical stress results in early ageing and may serve as an initiating factor more specifically for neurodegenerative disorders like Alzeihemer's disease and dementias. The current findings support the notion that incorporating dietary antioxidants like curcumin, ascorbic acid and α-tocopherol in routine diet from early age may help combat the risk of developing such disorders in ensuing years.  相似文献   
95.
为了更好地分析钢筋混凝土梁受集中荷载作用下的受力情况,利用通用有限元分析软件ANSYS10.0,对一钢筋混凝土简支梁进行静力和动力分析。分析结果显示ANSYS10.0能较好地模拟工程实际中的钢筋混凝土梁,真实地反映其破坏的典型力学特征。  相似文献   
96.
冯泽玉 《大众科技》2016,(7):149-151
文章在阐述组织承诺与压力管理的概念解析和关系认识基础上,同时基于对组织承诺与压力管理的问题进行诊断,从组织层面提出了两者的关系优化路径。  相似文献   
97.
PCOS is a heterogeneous endocrine disorder with diverse clinical presentation. Oxidative stress plays a key role in the pathophysiology of this disease. Serumhigh sensitive C-reactive protein (hsCRP), a marker of chronic low grade inflammation, is indicative of future development of cardiovascular disease. Our aim is to evaluate the oxidant status and hsCRP levels in PCOS. The study involved 61 cases and 61 controls in the age group of 18–40 years diagnosed with PCOS. Erythrocyte malondialdehyde (MDA), superoxide dismutase (SOD), serum hsCRP, gonadotrophins, thyroid stimulating hormone, prolactin, glycemic status and lipid profile were estimated. Erythrocyte MDA (p < 0.001), SOD (p = 0.007) and serum hsCRP (p < 0.001) were significantly elevated in PCOS patients than controls. Oxidative stress is present in women with PCOS along with elevated hsCRP.  相似文献   
98.
周德书 《图书馆论坛》2005,25(6):152-155
从体育院校图书馆评估的基本内容和重点、体育院校图书馆发展现状与评估指标的列比分析、体育院校图书馆今后发展的重点、体育院校图书馆深入发展的对策几方面探讨了图书馆评估及体育院校图书馆事业的深入发展。  相似文献   
99.
大强度运动对机体免疫功能的影响   总被引:3,自引:0,他引:3  
大强度运动可降低机体的免疫功能,可能与运动时的应激反应、运动时红细胞免疫力降低、运动性贫血、自由基生成增多、线粒体变性以及运动时的营养消耗有关。  相似文献   
100.
In the present study, witnessing in-home violence and peer relationship quality are evaluated as to their relative impact on Post Traumatic Stress (PTS) symptoms among children aged 8 to 17 investigated by child protective services (CPS) for maltreatment exposure. The sample included 2151 children from the National Survey of Child and Adolescent Well-Being II (NSCAW II). Linear growth models were estimated to assess associations between changes in PTS symptoms, witnessing in-home violence, and peer relationship quality over time. Greater frequency of witnessing in-home violence at baseline (i.e. wave 1) was associated with higher baseline PTS symptoms (β = 0.44). Increases in witnessing in-home violence frequency over time (average annual change across three years) had a strong association with increases in PTS symptoms over time (β = 0.88). Baseline peer relationship quality was associated with fewer PTS symptoms at baseline (β = −0.45). Increases in peer relationship quality over time were strongly associated with declines in PTS symptoms over time (β = −0.68). Peer relationship quality at baseline did not moderate baseline or over time associations between witnessing in-home violence and PTS symptoms. The average decline in PTS symptoms due to decreases in witnessing in-home violence and increases in peer relationship quality was 0.51 and 0.65 standard deviations respectively, over the three-year study period. Reducing chronic witnessing in-home violence and promoting the development of healthy social relationships with peers are critical for PTS symptom recovery.  相似文献   
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