大型焊接构件疲劳寿命评估系统

运用断裂力学有关应力强度因子理论,提出用断裂率Kt以及载荷率St为失效双判据的缺陷评定图对含裂纹焊接构件进行安全评定。以Paris公式为理论依据,对含裂纹焊接构件剩余寿命预测系统进行了设计和实现。该系统分为4个模块：数据采集模块、裂纹临界尺寸计算模块、FAD缺陷评定模块、安全评定结果输出模块。系统能够根据给定的数据对含裂纹大型焊接构件进行快速有效的评估分析、合理评价以及寿命预测。     

提高射流泵性能的途径研究

效率、噪声和运行寿命是射流泵的三个主要性能指标．本文依据大量原、模型试验结果，尤其通过对泵内水流流态的观察，分析了影响射流泵上述性能指标的若干因素和主要原因．认为：影响效率的主要因素是面积比，噪声主要来自于泵的尸重汽蚀，预防汽蚀、提高易损部件材质，可有效地延长泵的运行寿命．在为大寨、漫湾等电厂的供排水射流泵设计中采取相应措施，收到了较为良好的效果．为提高泵的性能指标、设计性能优良的射流泵探索了一条可供借鉴的途径．     

Molecular mechanisms for anti-aging by natural dietary compounds

Aging is defined as a normal decline in survival with advancing age; however, the recent researches have showed that physiological functions of the body change during the aging process. Majority of the changes are often subject to a higher risk of developing diseases, such as cardiovascular disease, type II diabetes, Alzheimer's disease, Parkinson's disease, as well as the dysregulated immune and inflammatory disorders. Aging process is controlled by a complicated and precise signaling network that involved in energy homeostasis, cellular metabolism and stress resistance. Over the past few decades, research in natural dietary compounds by various organism and animal models provides a new strategy for anti-aging. Natural dietary compounds act through a variety mechanisms to extend lifespan and prevent age-related diseases. This review summarizes the current understanding on signaling pathways of aging and knowledge and underlying mechanism of natural dietary compounds that provide potential application on anti-aging and improve heath in human.     

山茱萸多糖延缓秀丽隐杆线虫衰老的药效评价及机制研究

目的 考察山茱萸多糖（Corni Fructus polysaccharides, CFP）对线虫衰老的延缓作用并探讨其作用机制。方法 以野生型秀丽隐杆线虫（N2线虫）作为动物模型,利用百草枯建立氧化应激模型,筛选CFP的最佳药效浓度;测定CFP对N2线虫的急性热应激、寿命、生殖及咽泵运动能力的影响;检测并比较给药组与空白组活性氧簇（Reactive Oxygen Species, ROS）及脂褐素水平;运用实时荧光定量PCR检测CFP对N2线虫衰老相关基因mRNA表达的影响。结果 通过抗氧化应激实验测得CFP最佳给药浓度为150 μg/mL;急性热应激实验中,CFP给药组较空白组的生存曲线右移;不同浓度 CFP给药组较空白组的存活率更高（P<0.01）,平均寿命（P<0.001）和最长寿命均延长;给药组子代数量在第1、3、5、7 d 无显著性差异(P>0.05);50 μg/mL、150 μg/mL的CFP组均可增强N2线虫咽泵运动能力（P<0.05）;不同浓度CFP给药均能显著降低N2线虫体内ROS含量和减少脂褐素沉积;与空白组相比,150 μg/mL CFP给药5 d后,DAF-16、SKN-1、SOD-3及CTL-2的mRNA转录水平均显著上调,AGE-1的mRNA转录水平显著下调。结论 CFP能在一定程度上延缓秀丽线虫的衰老,其作用机制与提高线虫体内抗氧化应激能力、抑制ROS产生、减少脂褐素的沉积,以及调控胰岛素/胰岛素样生长因子-1(IIS)通路上的基因表达有关。     

延长牙轮钻具穿孔寿命的研究与实践

论述了牙轮钻机的推广应用以及牙轮钻机与其钻具的关系,并通过对45-R牙轮钻具系列产品的开发研究与使用实践,找出了影响其寿命的原因,提出了延长牙轮钻具穿孔寿命的有效途径。     

A study on the time-dependent changes of the intensities of factors determining patent lifespan from a biological perspective

The lifespan of a human is determined by inborn factors including genetic factors and acquired factors, such as social-environmental factors and individual-behavior. From this point of view, this study classified factors determining the economic lifespan of patents into inborn “genetic factors,” acquired “social-environmental factors,” as well as “individual-behavioral factors,” and analyzed the change in the influence intensity of factors with patent age along with application year. The results showed that the intensities of factors determining patent lifespan differed by industry and changed with the maintenance period and application year. Moreover, while “social-environmental factors” (such as a patent litigation), together with “individual-behavioral factors” (such as the number of patent family) had a stronger influence on patent lifespan than “genetic factors” (such as the number of claim), patents maintained longer period had stronger influence of behavioral and environmental factors rather than genetic factors. Furthermore, recently applied patents had a stronger influence due to the external environments than patents applied a relatively long time ago.     

棉纺细纱机钢领使用寿命的探讨

深入分析了钢领使用情况后,得出重要的结论是：钢领的结构、表面光洁度、表层组织、表面强度、锭子转速、钢丝圈匹配等对钢领的使用寿命影响很大。     

混凝土大坝的工程寿命评估及评价方法

通过对混凝土大坝的评估,分析了影响混凝土大坝工程寿命的因素,总结了混凝土大坝工程寿命的评价方法,提出了延长混凝土大坝工程寿命的方法,以便维护混凝土大坝的安全运行。     

Energy optimal routing for long chain-type wireless sensor networks in underground mines

Wireless sensor networks are useful complements to existing monitoring systems in underground mines.They play an important role of enhancing and improving coverage and flexibility of safety monitoring systems. Regions prone to danger and enyironments after disasters in underground mines require saving and balancing energy consumption of nodes to prolong the lifespan of networks. Based on the structure of a tunnel, we present a Long Chain-type Wireless Sensor Network (LC-WSN) to monitor the safety of underground mine tunnels. We define the optimal transmission distance and the range of the key region and present an Energy Optimal Routing (EOR) algorithm for LC-WSN to balance the energy consumption of nodes and maximize the lifespan of networks. EOR constructs routing paths based on an optimal transmission distance and uses an energy balancing strategy in the key region. Simulation results show that the EOR algorithm extends the lifespan of a network, balances the energy consumption of nodes in the key region and effectively limits the length of routing paths, compared with similar algorithms.