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41.
Social media utilities have made it easier than ever to know about the range of online or offline social activities one could be engaging. On the upside, these social resources provide a multitude of opportunities for interaction; on the downside, they often broadcast more options than can be pursued, given practical restrictions and limited time. This dual nature of social media has driven popular interest in the concept of Fear of Missing Out – popularly referred to as FoMO. Defined as a pervasive apprehension that others might be having rewarding experiences from which one is absent, FoMO is characterized by the desire to stay continually connected with what others are doing. The present research presents three studies conducted to advance an empirically based understanding of the fear of missing out phenomenon. The first study collected a diverse international sample of participants in order to create a robust individual differences measure of FoMO, the Fear of Missing Out scale (FoMOs); this study is the first to operationalize the construct. Study 2 recruited a nationally representative cohort to investigate how demographic, motivational and well-being factors relate to FoMO. Study 3 examined the behavioral and emotional correlates of fear of missing out in a sample of young adults. Implications of the FoMOs measure and for the future study of FoMO are discussed. 相似文献
42.
Journal of Failure Analysis and Prevention - To investigate the strength and fatigue life of a fracture-split connecting rod, this study combines experiments on connecting rod fracture splitting,... 相似文献
43.
Beta-solidifying TiAl alloy has great potential in the field of aero-industry as a cast alloy.In the present work,the influence of cooling rate during mushy zone on solidification behavior of Ti-44Al-4Nb-2Cr-0.1B alloy was investigated.A vacuum induction heating device combining with temperature control system was used.The Ti-44Al-4Nb-2Cr-0.1B alloy solidified from superheated was melted to β phase with the cooling rates of 10,50,100,200,400 and 700 K·min~(-1),respectively.Results show that with the increase in cooling rate from 10 to 700 K·min~(-1),the colony size of α_2/γ lamella decreases from 1513 to48 urn and the solidification segregation significantly decreases.Also the content of residual B2 phase within α_2/γlamellar colony decreases with the increase in cooling rate.In addition,the alloy in local interdendritic regions would solidify in a hypo-peritectic way,which can be attributed to the solute redistribution and enrichment of Al element in solidification. 相似文献
44.
Zr-based bulk metallic glass and copper with different surface roughness were soldered using low temperature eutectic Au-12 Ge(wt%) solder on a thermomechanical simulator. The cross-sectional microstructures of the brazed joints were analyzed by scanning electron microscopy(SEM) and transmission electron microscope(TEM) in detail, and the compositional distribution along the interface was analyzed by energy-dispersive spectrometer(EDS). Results show that the surface roughness of base metals plays an important role in the quality of the brazed joint because the surface roughness can enlarge the effective contact area, which can improve the brazing surface quality between two materials. A moderate roughness of treated Zr-based metallic glass of 18 μm is shown to be the best for the soldering, while the surface roughness has a weak effect on the soldering behavior of Au-12 Ge solder on copper. After soldering, long-range diffusion of atoms occurs between the base metal and solder, and five distinct regions are formed at the joint region. 相似文献
45.
46.
Lijia An Dayong He Jiaokai Jing Rongtang Ma Zhenhua Jiang Xichun Kou 《应用聚合物科学杂志》1996,59(12):1843-1847
The blends of polyethersulfone and phenoxy were prepared by melt mixing in a Brabenderlike apparatus. The specimens for measurements were made by compression molding and then were water-quenched at room temperature under pressure. The tensile strength, tensile modulus, elongation at break and yield, density, thermal analysis, and dynamic mechanical properties were each measured. The dependence of tensile strength, tensile modulus, elongation at break and yield, and density on composition was obtained. The relationship between tensile modulus and elongation at break and yield and speed of the crosshead at different weight ratios of the blends is shown. The effects of composition and miscibility on the mechanical properties are discussed. © 1996 John Wiley & Sons, Inc. 相似文献
47.
介绍用ARM7微控制器LPC2214和MPEG-1压缩芯片SZ1510实现数字视频压缩记录的嵌入式系统。SZ1510在LPC2214的控制下,完成音频和视频数据的实时压缩和码流合成,LPC2214同时完成码流的传输和存储控制。利用LPC2214的I/O端口实现IDE接口的扩展,可直接驱动大容量硬盘和CF存储卡。 相似文献
48.
49.
生长温度稳定性对两面顶细粒度金刚石性能的影响 总被引:4,自引:0,他引:4
在两面顶细粒度金刚石合成中采用PtRh30-PtRh6(双铂铑热电偶)测量温度,测得了合成芯块内部温度,得出了加热功率曲线与晶体生长温度的对应关系。根据多次实验结果,建立了生长温度稳定性具有显著差异的四种典型功率曲线;并分析了各曲线对应的温度变化趋势及幅度,四种曲线中温度变化幅度最大超过70%,最小可控制在10℃以内。对各曲线合成的金刚石进行了扫描电镜(SEM)及专门的产品指标对照分析,发现晶体生长温度越稳定晶体质量越好;将晶体生长温度控制在10%以内,能使细粒度晶体质量的综合指标提高5%-10%。 相似文献
50.
压力、功率梯度对金刚石性能的影响 总被引:1,自引:1,他引:0
本文旨在研究两面顶合成工艺中金刚石在生长阶段通过改变压力、功率梯度实现改变生长驱动力后对金刚石性能的影响,分析了相应的影响机理。在间接加热腔体结构中,金刚石生长过程采用两种压力、功率梯度进行合成,合成后对所得的样品进行了静压强度、冲击强度、表面形貌检测。结果表明:生长前期的压力和功率梯度增加两倍,生长后期梯度减缓,TTI和TI分别增加了10%。研究认为生长早期压力、功率大梯度(压力增幅大,功率降幅大)有利于提高晶体内部质量,生长后期压力、功率小梯度(压力增幅小,功率降幅小)有利于提高晶体外部质量。 相似文献