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41.
Li Xiaoxue Cao Yanan Li Qian Shang Yanmin Li Yangxi Liu Yanbing Xu Guandong 《World Wide Web》2021,24(1):85-103
World Wide Web - User identity linkage is a task of recognizing the identities of the same user across different social networks (SN). Previous works tackle this problem via estimating the pairwise... 相似文献
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Wafer curvature method has been applied to determine the internal stress in the films using Stoney’s equation. During the film deposition, the wafer fixation on the sample holder will restrict the deformation of the rectangle-shaped wafer, which may result in the stress datum difference along length and width direction. In this paper, the effect of wafer size and the wafer fixation on the TiN film internal stress measured by wafer curvature method was discussed. The rectangle-shaped wafers with different length/width ratios (L/W=1:1, 2:1, 3:1 and 4:1) were fixed as a cantilever beam. After the TiN films deposition, the profiles of the film/wafer were measured using a stylus profilometer and then the internal stress was calculated using the Stoney equation in the film. The results showed that the fixed end of the wafers limited to some degree the curvature of the wafers along the width direction. For film internal stress measured by wafer curvature method, the wafer profile should be scanned along the length direction and the scan distance should be greater than or equal to half of wafer length. When the length/width ratio of the wafer reached 3:1, the wafer curvature and the calculated stress were basically the same at different positions along the length direction. For film internal stress measured by wafer curvature method, it was recommended that the length/width ratio of wafer should be considered to be greater than or equal to 3:1, and the deformed profile was scanned along the length direction. 相似文献
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利用水泥粉磨过程中的机械力促使水解聚马来酸酐(HPMA)与聚乙二醇单甲醚(MPEG)进行酯化反应形成聚羧酸助磨剂。试验研究了HPMA、MPEG、HPMA与MPEG的混合物、HPMA与MPEG的反应合成物对水泥助磨效果以及对砂浆性能的影响。结果表明,HPMA与MPEG都有一定的助磨性,HPMA与MPEG的混合物和反应合成物具有更佳的助磨性能,且可以改善水泥砂浆的流动性能和显著提高水泥砂浆的早期强度。激光拉曼光谱测试表明HPMA与MPEG的混合物和反应合成物与水泥共同粉磨后吸附在水泥颗粒表面,具有相似的拉曼位移图谱。 相似文献
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Shuai Huang Lixin Yu Kangliang Peng Youjun Zhao Jindi Wang Mengmeng Shang 《Journal of the American Ceramic Society》2021,104(11):5848-5858
To enhance the display quality of light-emitting diodes (LEDs), it is of great significance to exploit green/yellow-emitting phosphors with narrow emission band, high quantum yield, and excellent color purity to satisfy the application. Herein, orthophosphate-based green/yellow-emitting Na3Tb(PO4)2:Ce3+/Eu2+ (NTPO:Ce3+/Eu2+) phosphors have been successfully synthesized by a facile solid-state reaction method. The absorption band of NTPO samples was extended to the near-ultraviolet region and the absorption efficiency was significantly improved owing to a highly efficient energy transfer from Ce3+/Eu2+ ion to Tb3+ ion in NTPO host certified by time-resolved PL spectra. Upon 300 nm excitation, the NTPO:Ce3+ is characterized by ultra-narrow-band green emission of Tb3+ with an absolute quantum yield of 94.5%. Unexpectedly, NTPO:Eu2+ emits bright yellow light with a color purity of 73% as a result of the blending of green light emission from Tb3+ and red light emission from Eu3+. The thermal stability has been improved by controlling the stoichiometric ratio of Na+. The prototype white LED used yellow-emitting NTPO:Eu2+ phosphor has higher color-rendering index (Ra = 83.5), lower correlated color temperature (CCT = 5206 K), and closer CIE color coordinates (0.338, 0.3187) to the standard white point at (0.333, 0.333) than that used green-emitting NTPO:Ce3+ phosphor, indicating the addition of the yellow light component improved the Ra of the trichromatic (RGB) materials. 相似文献
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针对采用激光焊接工艺的金刚石锯片上,其金刚石刀头内弧面需要磨抛的工艺要求,研发了一种自动金刚石刀头磨弧机。该设备将金刚石刀头放置在作间歇回转的工作转盘上,工作转盘由槽轮机构驱动;磨削砂轮安装在拖板系统上,拖板的间歇往复运动由一种在滑块上开有长槽的曲柄滑块机构实现,可满足工作转盘转位时,拖板停歇;工作转盘停歇时,拖板运动的工作要求。用靠模控制砂轮磨削的进给量。通过靠模的更换及设计能快速装卡的刀头夹具,可实现对不同弧度刀头的磨弧。本文介绍了该设备的结构组成、设计参数的选择及相关的设计方案,并对在滑块上开有长槽的曲柄滑块机构的设计方法进行了详细地讨论。 相似文献
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研制了一种基于空心微针阵列并可微痛刺入皮下实时连续监测人体血糖浓度的葡萄糖传感器.微针阵列由等间距的三根微针组成,分别作为工作电极、辅助电极和参比电极,其中工作电极与辅助电极采用表面溅射了Ti/Pt的空心不锈钢微针来制作,采用戊二醛-牛血清白蛋白交联法将葡萄糖氧化酶固定并仅置于作为工作电极的针尖通孔处;参比电极采用Ag/AgCl实心微针制作.测试结果表明:葡萄糖浓度在0~21 mmol·L-1范围内传感器输出电流为线性,灵敏度为0.575 μA/(mmol·L-1),响应时间为16s,且具有很好的抗干扰性. 相似文献
50.
The design and test of dual/triple‐mode bandpass filter based on temporal coupled‐mode theory 下载免费PDF全文
Hui Xu Jiong‐Jiong Mo Xiu‐Qin Xu Xu Ding Zhi‐Yu Wang Yong‐Heng Shang Li‐Ping Wang Fa‐Xin Yu 《国际射频与微波计算机辅助工程杂志》2016,26(7):609-622
In this article, the design and test of both a K‐band dual‐mode bandpass filter (BPF) pair and a K‐band triple‐mode BPF are presented based on N‐mode temporal coupled‐mode theory (CMT). The expressions of transmission and reflection responses are analytically derived. All the parameters in the expressions have clear physical meanings and are easily optimized to reach the required filter performance. Aided by eigenmode simulations, concrete structures of the three integrated BPFs are designed and optimized to approach the calculated physical parameters. After the fabrications and measurements of the three BPFs, extended upper/lower stopband with high stopband rejections are achieved, and by increasing the number of resonant modes, improved frequency selectivity and better passband flatness are obtained. The analytical analysis well predicts the simulation and measurement results, which provides an efficient way for BPF designs. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:609–622, 2016. 相似文献