The influence and moderating effect of trust in streamers in a live streaming shopping environment

With its powerful real-time interaction and rich user experience, live streaming shopping has rapidly become consumers' new favorite. However, the frequent "rollover" incidents affecting the reputation of well-known streamers significantly reduce consumers' trust in the streamers. Academic research on trust in live streaming shopping has thus far mainly focused on purchase motivations. Few studies have focused on the factors influencing trust from the streamer's perspective, and they have ignored the moderating role of streamers and product factors, situational factors and individual characteristics of consumers. Therefore, this study introduces three new moderating variables – streamer-product matching, live streaming online reviews, and online shopping experience – to explore their moderating effects on streamers' reputation, popularity, and trust. The results show that streamers' reputation and popularity have a significant positive impact on trust in streamers, and streamer-product matching has a positive moderating effect on the relationship between streamers' reputation, streamers' popularity, and trust in streamers. Online reviews have a positive moderating effect on the relationship between streamers' popularity and trust, while online shopping experience has a positive moderating effect on the relationship between streamers' reputation and trust in streamers.     

针-板式流光放电结合脉冲电源降解甲苯

放电等离子反应器的结构与高压电源的匹配对于VOCs的降解产生重要影响.采用针-板式反应器并引入脉冲高压和交流高压,采用3种不同电极形状(锥形、圆台、扁平)对甲苯的降解特性进行了实验研究.结果发现:脉冲电源可以提高电极间的击穿电压,并使流光放电更加稳定,产生瞬间高能粒子,从而提高甲苯的脱除效率;不同的电极形状对放电特性及降解率产生影响,圆台形电极获得最大的甲苯降解率和降解效率.     

氩气等离子体羽从实心到空心的放电特性

对大气压环境中偏置正弦电压激励的氩气等离子体射流进行了研究. 结果表明,随着偏置电压从负值增加到正值,所产生的羽从实心过渡到空心. 利用电学和光学手段对实心羽和空心羽的放电特性进行了研究,发现对于这2种羽,每个电压周期都只有单个放电脉冲. 利用快速摄影,看到“胖”定向子弹在实心羽中传播,其中涉及负流光机制. 而空心羽中涉及正流光机制,它表现为从棒电极端开始的定向流光,随后逐渐演变成在气流周边传播的分叉流光. 利用光谱学手段,研究了距离管口不同位置处的电子温度. 基于潘宁电离和残留负离子的作用,对这2种羽的产生机制进行了解释.     

外加电压参数对大气压等离子体射流形貌的影响

大气压等离子体射流可以在开放的空气环境中产生富含多种活性粒子的低温等离子体羽,在材料合成、表面改性、生物医疗、环境保护等多种领域具有广泛的应用前景. 等离子体羽的形貌与活性粒子的时空分布有关,研究其形貌对等离子体射流的应用具有重要意义.针对目前等离子体形貌还不够丰富的问题,本文利用氩气等离子体射流,通过改变外加电压参数(电压峰值、驱动频率和偏置值)产生了几种形貌的等离子体羽(弥散圆锥状、丝加晕形、念珠串状和空心锥状),从而进一步丰富了等离子体羽的形貌.通过对比放电的电压和发光信号波形,发现除丝加晕形等离子体羽外,其他3种等离子体羽在每个外加电压周期均放电1次.不同的是,弥散圆锥状和念珠串状等离子体羽的放电出现在电压负半周期,为负放电.而空心锥状等离子体羽的放电出现在外加电压正半周期,为正放电.丝加晕形等离子体羽每个电压周期存在1个负放电和1个正放电.此外,还利用高速成像设备对这几种形貌等离子体羽的时空演化进行了研究.相关结果表明,负放电对应负流光的传播过程,而正放电对应正流光的过程.视觉上不同形貌的等离子体羽是正流光、负流光及其组合时间叠加的结果.本文的结果对大气压等离子体射流中等离子体羽形貌的深入研究及流光动力学的进一步发展均具有重要价值.     

正脉冲电晕放电的数值研究

根据等离子体的流体方程提出了脉冲电晕放电中流注形成和传播的数学模型，导出了流注空间电荷电场的普遍积分表达式．用Ｆｌｕｘ－ＣｏｒｒｅｃｔｅｄＴｒａｎｓｐｏｒｔ（ＦＣＴ）算法，就实验中所用的超窄脉冲电压波形对该模型进行了数值求解，得到了带电粒子密度、电场和电子温度等参量沿流注发展轴线上的时空分布     

Coronal structure and brightness profile of the total solar eclipse on August 1, 2008

Solar corona is the outermost part of the solar atmosphere. Coronal activities influence space environment between the Sun and the Earth, space weather and the Earth itself. The total solar eclipse （TSE） is the best opportunity to observe the solar corona on ground. During the TSE 2008, a series of images of the corona and partial eclipse of solar disk were obtained using telescope and CCD camera. After image processing, preliminary results of coronal structure are given, and radial brightness profiles of the corona in directions of pole and equator of the Sun are measured. Though in solar activity minimum, the shape and structure of the corona are not symmetry. The equatorial regions are more extent than the polar one, and there are also larger differences between the east and west equatorial regions and between the south and north polar regions. Coronal streamers on east side of the equator, particularly the largest one in east-south direction, are very obvious. The coronal plume in south polar region consists of more polar rays than that in north polar region. These structures are also shown in other observations and data of SOHO. The radial brightness profiles in directions of pole and equator are similar to those of the Van de Hulst model in solar minimum, but there are a few differences due to coronal activity, which is shown in the isophote map of the corona.     

砷化镓光导开关中流注890 nm辐射的光致电离效应

分析了高增益砷化镓光导开关中流注一端波长890 nm自发辐射的光致电离效应,导出了砷化镓光导开关中流注顶部波长890 nm自发辐射在吸收区域产生的载流子密度分布规律.计算结果表明,紧邻流注顶部处的光生载流子密度最大,波长890 nm自发辐射产生的最大载流子密度比流注内平均载流子密度至少小3个数量级.     

正极性雷云作用下避雷针流注形成研究

讨论了在正极性雷云作用下避雷针流注形成过程,对从电子崩出现到流注形成的整个初始放电过程进行了分析。使用含电子、正离子、负离子的连续方程对雷电下气体的放电过程建模,通过耦合泊松方程求解空问电荷对电场的畸变影响。采用变量耦合计算得到了整个过程中电子浓度、正离子浓度、电子热能的空间分布,分析了电子浓度、正离子共同作用下对电场的影响。通过分析还得出在电子浓度高的区域电子热能并不高,两种的分布趋势并不完全一致。     

冕流的白光偏振

研究了日冕白光冕流的偏振特性,包含：典型冕流的偏振度随日心距增大的变化;冕流白光高度在同一日心距处沿日面位置角的分布;不同日面纬度处冕流的偏振器;冕流中偏振亮度分布的不均匀性。