铝制板翅式换热器真空钎接下凹原因探讨

基于铝制板式体的基本结构,提出了板式体真空钎接下凹形成原理,并在此基础上分析了影响板式体钎接下凹的因素:材料的影响、天气的影响、板式体外形的影响及钎接温度的影响。最后针对下凹问题,提出了几点改进意见。     

化学镀镍溶液渗透对多孔PTC陶瓷影响的机理研究

通过对比实验研究了化学镀镍溶液渗透对多孔ＰＴＣ陶瓷影响的机理。结果表明，这种影响是由溶液中的还原剂引起的，镀液中的其它物质的渗透对ＰＴＣ陶瓷的性能没有影响或者影响很小。提出了化学镀镍溶液中的还原剂对ＰＴＣ陶瓷的晶界产生还原从而影响ＰＴＣ效应的观点。化学镀镍溶液渗透造成的这种影响可以通过一定温度下的氧化热处理而消除。     

Determination of influence weights for scientific journals

A new citation matrix is proposed for the computation of journal influence weights applying Geller's methodology. Instead of self-citations, references to fringe journals are introduced and the proportions of all references (without self-citations) are used as matrix elements. On the basis of the determined weights, relative weights for fringe journals are calculated, i.e. the initial set (core) of journals is extended and simultaneously a rank order is obtained (by total influence and influence per article). The procedure is examplified on elementary particle physics (EPP) journals. Using first a reference/citation criterion, eight core journals were determined by iteration and then influence weights were calculated. A ranking by total influence and influence per article is presented for core and fringe journals in EPP.     

反演解析法提高CCD成像分辨率的噪声影响研究

反演解析法是提高CCD成像分辨率的方法之一。但是，加在低分辨率图像上的随机噪声会对合成的高分辨率图像产生不可预知的影响。中首先介绍了反演解析法原理，然后讨论了噪声的影响机制。并且，为了对噪声影响进行数值化分析，提出了一个噪声影响评价函数。最后，以该函数为基础，通过计算机仿真实验，找到了合成图像受随机高斯白噪声影响的规律。     

交通吸引源对道路交通影响的机理与算法

针对道路交通吸引源与道路之间进出交通流的影响流程和特征,分析了交通吸引源对道路交通流的影响机理,探讨了交通吸引源对道路运行车速、车道通行能力等道路交通服务水平的影响幅度算法,并给出相应条件下的数值参考。     

添加微量锡对铜基摩擦材料性能的影响

研究了添加微量锡对铜基摩擦的摩擦性能的影响。结果表明，微量锡对摩擦系数无显著影响，但对磨损有显著影响，当锡含量为０．５０％时，摩擦材料及对偶材料的磨损都较小。     

爆破对边坡影响范围的声波测试与评价

通过声波测试,对比分析了采用缓冲爆破和未采用缓冲爆破时,爆破施工对边坡的影响范围,测试结果表明采用缓冲爆破技术可以明显减小爆破施工对边坡的影响范围,对于边坡具有良好的保护作用.     

含脱胶缺陷复合材料L形接头拉脱强度实验研究

为考察脱胶缺陷对整体化结构在面外拉伸载荷下承载能力的影响, 实验研究了脱胶形状、间距、位置和尺寸对L形接头拉脱强度的影响规律, 定量评估了脱胶对L形接头拉脱强度的影响程度, 提出了脱胶缺陷对L形接头拉脱强度影响的定量表征参数。结果表明, L形接头的拉脱强度对脱胶形状、脱胶间距的变化不敏感, 对脱胶位置和脱胶尺寸的变化较为敏感; 位于填充区所在胶接面区域的脱胶对L形接头拉脱强度影响最大; 随着脱胶尺寸特别是填充区所在胶接面脱胶尺寸的增大, 拉脱强度显著降低。     

Grundsätzliche Betrachtungen zur Oberflächen-Ermüdung

Rolling Contact Fatigue . Wear, rolling contact fatigue, fatigue – calculation of stresses – stresses caused by normal load – influence of friction – influence of surface roughness – influence of residual stresses – influence of temperature – influence of pressure profile in EHL-contacts – influence of material – influence of lubricants – influence of additives – size effect – investigation of damages.     

Influence of displacement and its first- and second-order derivative components on curvature fringe formations in speckle shearography

The influence of displacement and its first- and second-order derivative components on curvature fringe formations in speckle shearography is discussed. The results show that (a) all the displacement components have no direct influence on curvature fringe formations; (b) only the first-order derivative component along the centerline of three apertures has an influence on curvature fringe formations, whereas all the other first-order components have no influence; and (c) all the second-order derivative components have no influence on curvature fringe formations. Results from theory and experiments are in good agreement.     

Strength of welded joints of Cr–Mn steels with elevated content of nitrogen in hydrogen-containing media

We analyze the operating characteristics of welded joints of austenitic high-nitrogen steels. The influence of hydrogen- and chloride-containing media on the structurally sensitive properties of heterogeneous welded joints is investigated. It is shown that the heat-affected zone, where the residual welding stresses are superimposed on the stresses caused by the influence of the ambient media and in-service defects, proves to be especially sensitive to the influence of hydrogen degradation.     

数字印刷中调频加网线数对印刷质量的影响

目前数字印刷加网多采用调频加网,介绍了一个改变加网线数从而影响印刷输出效果的实验,分析了调频加网线数如何影响数字印刷图像质量,以及提高数字印刷图像输出设备输出精度的必要性.     

轨道刚度对高速轮轨系统振动噪声的影响

高速铁路对环境的噪声污染是一个不可忽视的问题,在已建立的轮轨滚动噪声预测模型的基础上,以板式轨道为对象,研究了在轮轨表面粗糙度(随机短波激扰)的激励下,轨道刚度变化对高速轮轨系统振动及轮轨噪声的影响.结果表明:降低轨道刚度,可以有效降低轮轨系统400Hz以下频率的振动,但对400Hz以上的振动基本无影响,从而,对轮轨噪声也基本无影响.     

A comparison of overall and sub-area journal influence: The case of the accounting literature

In most scientific disciplines, a number of divergent and often highly specialized research areas are examined, which is reflected in substantial differences among journal scopes. Using the accounting literature as an example, we argue that this diversity in scopes should be considered when assessing journal influence. Concretely, we examine a citation-based structural influence measure for a sample of 41 accounting journals. Next, we identify sub-areas in the accounting literature and we explore journal influence in these sub-areas. Our results clearly demonstrate the importance of distinguishing between overall and sub-area influence. In addition, we show that sub-areas should be identified using a fuzzy clustering procedure.     

电子膨胀阀对制冷系统的影响

通过改变电子膨胀阀的开度,以及在试验箱体内加入不同的热负荷条件,研究了电子膨胀阀对制冷系统的影响,并对制冷循环参数的影响进行了分析。     

近场项对车用交流发电机气动噪声影响分析

为了探究近场项(反射面、端盖及定子)对车用交流发电机气动噪声的影响,基于Lighthill声比拟理论,大涡模拟(LES)方法及边界元法对交流发电机的气动噪声特性进行研究。结果表明:仿真得到的主要阶次及幅值与实验相比一致性较好,验证了仿真方法的正确性;第4、6、8、9、10及12阶次为该型交流发电机的主要阶次;反射面对各主要阶次皆有影响,端盖主要影响10阶次,定子主要影响6及9阶次;反射面对左、上测点声压级影响较大,端盖对左、右测点影响较大,定子对各测点几乎无影响;近场项对五点平均总声压级的影响大小依次为:反射面>端盖>定子。     

Effect of carbonation on the rebound number and compressive strength of concrete

Experimental research was performed to clarify the influence of carbonation on the rebound number and the strength evolution of concrete for three strength levels. The results reveal that the strength level dependent influence of carbonation is a source of errors in the existing equations for the strength reduction coefficient; these equations are used to compensate for the influence of surface carbonation in the rebound number method. A new equation for the strength reduction coefficient that can consider the influence of strength level was developed based on field test data extracted from technical reports of the Korea Research Institute of Standards and Science and of four universities. Over a wide range of strength levels, the equation shows good agreement with strength reduction coefficients established experimentally.     

传感器温漂对磁悬浮转子控制精度的影响

传感器温漂对磁悬浮转子的控制精度有很大的影响．磁悬浮转子在运转时有较大的温升．磁悬浮转子的结构设计对其工作温度的高低及其分布有很大影响．本文研究了磁悬浮转子实际工作温度场的不均匀性,对涡流传感器的温度特性进行了实验测试,对传感器的布置形式对磁悬浮转子精度的影响进行了分析．研究了磁悬浮转子结构形式、结构参数、传感器的个数及其测试方式等对磁悬浮转子控制精度的影响程度和变化规律．在上述研究的基础上得出了减少传感器温漂对磁悬浮转子控制精度影响的结构设计原则．     

产品包装生命周期分析与可持续发展探讨

论述了产品生命周期分析法(MET),是一种用于评估产品在其整个生命周期中,对环境影响的技术和方法.此方法以环境保护为核心,对包装进行环境影响的研究;它辅助设计实现其包装对环境的最小化影响,以促使人们生存的环境资源协调发展,最终实现社会、环境与生态的可持续发展.     

SSRF增强器真空系统设计和真空室研制

为减少增强器弯转磁铁的交变磁场在真空室内感应的涡流对主磁场的干扰，SSRF增强器采用了椭圆截面的薄壁不锈钢真空室，并成功研制出样机，本文描述了增强器真空系统总体设计、真空室的材料选择、结构设计和物理计算（如涡流对主磁场的影响、真空室的真空负载变形、同步辐射光对真空室温升影响和真空室内压强分布），介绍了加工工艺。