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141.
应用SolidWorks软件,建立了螺杆压缩机机体三维实体模型.对螺杆压缩机机体的内、外螺旋面的建模进行了分析和研究,提出了建立分段螺旋面模型的基本思路和方法. 相似文献
142.
An adaptive optical sequence generation scheme has been described in a nonlinear optical ring which exhibits chaotic dynamics. The adaptation is based on avoidance of collisions between the ring output and signals from another source. It is shown that collision-avoiding sequences can be autonomously selected via chaotic mode transitions induced by the feedback of collision signals. Experimental results demonstrate that the method can be successful for various collision signal patterns with different periods and pulsewidths. The mechanism of inducing chaos with collision signals is examined both experimentally and with numerical simulations and the results verify the effectiveness of the proposed adaptation method. A possible application of the proposed signal generation scheme in intelligent optical communication networks is mentioned 相似文献
143.
采用金刚石薄膜作为阴-阳极间绝缘介质层是一种新型的微间隙室(MGC)结构。该文详细介绍和讨论了采用常规的微细加工工艺制备基于金刚石薄膜介质层的MGC的制备技术,其典型结构为阳极微条宽20μm,微条间隔180μm,器件探测区面积为38 mm×34 mm。采用热丝CVD法制备的金刚石薄膜作为阴-阳极间绝缘介质层,厚7~8μm,具有(100)晶面结构。金刚石的刻蚀采用反应离子刻蚀,Cr作掩膜,O2和SF6为刻蚀气体,刻蚀速率为79 nm/min,与Cr的刻蚀比约为20:1。实验结果表明,采用的微加工结合自套准工艺可很好地解决金刚石薄膜的制备、图形化及金属阳极电极与金刚石薄膜的相互套准等金刚石薄膜的可加工性及兼容性问题,并制备出采用金刚石薄膜作为电极间绝缘介质层的新型MGC结构。 相似文献
144.
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146.
A novel reconfigurable microstrip patch antenna with frequency and polarization diversities is proposed. A U‐slot is incorporated into a square patch, and a PIN diode is utilized to switch the slot on and off, which realizes the frequency diversity characteristic. The polarization diversities among linear polarization (LP), right‐hand circular polarization (RHCP), and left‐hand circular polarization (LHCP) are also obtained by switching three PIN diodes on the slot and the truncating corners of a square patch on and off. The antenna design and experimental results are presented. 相似文献
147.
CaO-Al2O3-MgO (CAM) ceramic fibre produced via inviscid melt spinning (IMS) was investigated for phase transformation. Differential thermal analysis (DTA) on the as-spun CAM fibre gave two transformation peaks, one for exothermic peak at around 927°C and the other for endothermic one at around 1100°C. In order to identify each phase transformation x-ray diffraction (XRD) analysis was performed on the CAM fibres heat-treated to each phase transformation completion temperature. The exothermic peak was determined to represent crystallization of remaining amorphous phase in the as-spun CAM fibre. The endothermic peak was determined to correspond to transformation of non-equilibrium CaO · Al2O3 phase to equilibrium 3CaO· 5Al2O3 phase. 相似文献
148.
Mei Xuan Xu Wen Guang Liu Yun Lin Guan Zuo Peng Bi Kang De Yao 《Polymer International》1995,38(2):205-209
The phase behavior of a hybrid polymer network (HPN) composed of poly[(propylene glycol maleate)-co-(propylene glycol phthalate)] crosslinked with styrene and polyester–urethane crosslinked with methylene-bis-ortho-chloroaniline was examined. The correlation between phase separation and impact strength of the HPNs is discussed. The composition of HPNs has an effect on their properties. 相似文献
149.
This study employs a relational dialectics approach to gain insights into the nature of relational communication via Cyworld , a Korean social network site. Qualitative analysis of in-depth interview data from 49 users suggests that Cyworld users routinely negotiate multiple dialectical tensions that are created within the online world, transferred from face-to-face contexts, or imposed by interpersonal principles that relate to Korea's collectivistic culture. The interviewees experienced a new relational dialectic of interpersonal relations versus self-relation, analogous to Baxter and Montgomery's (1996) connection-autonomy contradiction. Their responses suggest that Cyworld's design features and functions encourage users to transcend the high-context communication of Korean culture by offering an alternative channel for elaborate and emotional communication, which fosters the reframing of relational issues offline. Cy-Ilchons (online buddies) virtually extend the Korean cultural concept of blood ties, called yons, in ways that intensify the openness-closedness contradiction at early stages of relationship formation. 相似文献
150.
张蕴生 《消防技术与产品信息》2005,(2):45-46
从高层医院所应具备自动消防系统和在高层医院日常管理中 ,加强消防安全教育 ,建立管理制度 ,主动发挥“人”主观能动性的两个方面 ,具体阐述了高层医院的消防安全工作 相似文献