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991.
The mechanism of the FA/O chelating agent in the process of chemical mechanical polishing (CMP) is introduced. CMP is carried on a φ300 mm copper film. The higher polishing rate and lower surface roughness are acquired due to the action of an FA/O chelating agent with an extremely strong chelating ability under the condition of low pressure and low abrasive concentration during the CMP process. According to the results of several kinds of additive interaction curves when the pressure is 13.78 kPa, flow rate is 150 mL/min, and the rotating speed is 55/60 rpm, it can be demonstrated that the FA/O chelating agent plays important role during the CMP process. 相似文献
992.
Peng Zhang Wei Dou Zhenghua Ju Lizi Yang Xiaoliang Tang Weisheng Liu Youzhi Wu 《Organic Electronics》2013,14(3):915-925
The efficiency of fluorescent organic light emitting diodes (FOLEDs) is strongly affected by the fraction of singlet excitons formed. However, the standard statistical value of the single to triplet ratio is 1:3, which implies most of the excitons are invalid in fluorescent emitting devices. Here, we demonstrate the ability of twisted intramolecular charge transfer state (TICT-state) to enhance the occurrence of singlet excitons in a fluorescent emitter that is based on the 9,9′-bianthracene (BA) moiety. The anthracene–anthracene (A–A) linked by a single bond and having perpendicular electronic structure is a charge transfer intersystem crossing π system in excited state. The BA-cored fluorescence emitter (CzBACz) with particular TICT characteristics realizes the electron–hole (e–h) recombination via intramolecular conversion from charge-transfer excitons (immediate precursor) to radiative singlet exciton (final state). For CzBACz-based electroluminescent (EL) device, the singlet generation fraction is more than 25%. 相似文献
993.
Yali Qiao Mohammed Sayful Islam Kuo Han Eric Leonhardt Jiuyang Zhang Qing Wang Harry J. Ploehn Chuanbing Tang 《Advanced functional materials》2013,23(45):5638-5646
The discovery of nanodipolar π‐conjugated oligomer‐containing polymers as high performance nanodielectric materials with high permittivity and low dielectric loss over a wide range of frequency (100 Hz–4 MHz) is reported. Terthiophene‐containing methacrylate polymers are synthesized by reversible addition fragmentation transfer (RAFT) polymerization. Both X‐ray and thermal studies indicate the formation of small crystalline domains of terthiophene side chains dispersed in amorphous matrix. The highly polarizable and fast‐responsive nanodipoles from the nanoscale crystalline domains (<2 nm) are believed to dictate the performance. These polymers uniquely satisfy nanodipole architectures conjectured two decades ago to guide the design of high performance nanodielectric materials. This unprecedented approach can be generalized to a variety of π‐conjugated oligomer‐containing polymers for the development of high energy density capacitor materials. 相似文献
994.
A time-dependent non-linear theory is developed for ion channel electron cyclotron maser (ICECM), and the corresponding numerical calculation results are given for the first time. The theoretical analysis shows that the longitudinal plasma wave tends to enhance the energy exchange between the beam and wave. Using the numerical calculation of the self-consistent time evolution of scattering wave growth, the non-linear effect of ion density on the beam-wave interaction efficiency has been studied. The time norm, which must be satisfied in the operation of ICECM, is verified. Taking 6.8?×?1013?cm?3 ion density, 1?MV accelerated voltage and 1.5?KA beam current, the present numeric calculation results show that the pulse scattering wave power and the frequency can achieve about 200?MW and 284?G?rad/s respectively. 相似文献
995.
Wenping Zhu Shouyi Yin Siqi Hu Eugene Y. Tang Shaojun Wei 《International Journal of Electronics》2013,100(5):621-635
With the rapid proliferation of smartphones and tablets, various embedded sensors are incorporated into these platforms to enable multimodal human–computer interfaces. Gesture recognition, as an intuitive interaction approach, has been extensively explored in the mobile computing community. However, most gesture recognition implementations by now are all user-dependent and only rely on accelerometer. In order to achieve competitive accuracy, users are required to hold the devices in predefined manner during the operation. In this paper, a high-accuracy human gesture recognition system is proposed based on multiple motion sensor fusion. Furthermore, to reduce the energy overhead resulted from frequent sensor sampling and data processing, a high energy-efficient VLSI architecture implemented on a Xilinx Virtex-5 FPGA board is also proposed. Compared with the pure software implementation, approximately 45 times speed-up is achieved while operating at 20 MHz. The experiments show that the average accuracy for 10 gestures achieves 93.98% for user-independent case and 96.14% for user-dependent case when subjects hold the device randomly during completing the specified gestures. Although a few percent lower than the conventional best result, it still provides competitive accuracy acceptable for practical usage. Most importantly, the proposed system allows users to hold the device randomly during operating the predefined gestures, which substantially enhances the user experience. 相似文献
996.
给出了作为网络动画常用开发工具的软件Flash在多线切割机中的具体应用,介绍了用Flash结合VC进行上位机组态接口的制作,并详细说明了用VC实现对Flash控件调用的关键步骤,进而完成对整个多线切割设备动态监控的方法。 相似文献
997.
Yiqing Dong Teng Xu Heng-An Zhou Li Cai Huaqiang Wu Jianshi Tang Wanjun Jiang 《Advanced functional materials》2021,31(9):2007485
The explosive demands of storage capacity and the von Neumann bottleneck of modern computer architectures trigger many innovations in information technology. Amongst them, nonvolatile spintronics attract considerable attentions for which can embed the computation capability into memory, enable neuromorphic, and probabilistic computing. These exciting progresses typically rely on the manipulation of the relative magnetization orientations of two magnetic layers. By extending to 3D spintronic architectures made of multiple magnetic layers (n), the exponentially increased 2n magnetic states can provide ample opportunities for implementing novel spintronic functionalities. Here, through building perpendicularly magnetized 3D spin-orbitronic architectures – [Pt/Fe1−xTbx/Si3N4]n multilayers, it is demonstrated the electrical programing of 2n memory states via current-induced spin–orbit torques (SOTs), and the accompanied reconfigurable multifunction in-memory logic features in a single four-terminal Hall device. Further, an electrical readout of these 2n states, together with the implementation of Boolean logic gates and digital circuitry such as 2–4 and 3–8 decoders, are successfully conducted. More complex logic circuits are also envisioned. The experiments thus substantiate 3D spin-orbitronic structures as a promising platform for exponentially boosting the storage capacity and accommodating in-memory computing that can be important for promoting the emerging 3D nanospintronics. 相似文献
998.
Kai Lin Zhao Ma Jin Li Menghuan Tang Aaron Lindstrom Mythili Ramachandran Shaoming Zhu Tzu-yin Lin Lanwei Zhang Yuanpei Li 《Advanced functional materials》2021,31(10):2008460
Photodynamic therapy (PDT) has emerged as an attractive alternative in cancer therapy, but its therapeutic effects are limited by the nonselective subcellular localization and poor intratumoral retention of small-molecule photosensitizes. Here a fiber-forming nanophotosensitizer (PQC NF) that is composed of mitochondria targeting small molecules of amphiphilicity is reported. Harnessing the specific mitochondria targeting, the light-activated PQC NFs produce approximately 110-fold higher amount of reactive oxygen species in cells than free photosensitizers and can dramatically induce mitochondrial disruption to trigger intense apoptosis, showing 20–50 times better in vitro anticancer potency than traditional photosensitizers. As fiber-shaped nanomaterials, PQC NFs also demonstrated a long-term retention in tumor sites, solving the challenge of rapid clearance of small-molecule photosensitizers from tumors. With these advantages, PQC NFs achieve a 100% complete cure rate in both subcutaneous and orthotopic oral cancer models with the administration of only a single dose. This type of single small molecule-assembled mitochondria targeting nanofibers offers an advantageous strategy to improve the in vivo therapeutic effects of conventional PDT. 相似文献
999.
Jiaming Huang Zhiwei Ren Yaokang Zhang Kuan Liu Hengkai Zhang Hua Tang Cenqi Yan Zijian Zheng Gang Li 《Advanced functional materials》2021,31(16):2010172
Flexible photovoltaic devices are promising candidates for triggering the Internet of Things (IoT). However, the power conversion efficiencies (PCEs) of flexible organic photovoltaic (OPV) devices with high conductivity poly(3,4-ethylene dioxythiophene):polystyrene sulfonate (PEDOT:PSS) electrodes on plastic are lagging behind the rigid devices due to the low transmittance of polyethylene terephthalate (PET)/PEDOT:PSS. Moreover, the poor stretchability of the commonly used plastic substrates largely hinders the practical application of wearable devices. Herein, a novel stretchable indium tin oxide (ITO)-free OPV device with a surface-texturing polydimethylsiloxane (PDMS) substrate for outdoor strong- and indoor dim-light energy harvesting is reported. The high diffuse transmittance and haze effect of the substrate enable stretchable ITO-free devices, yielding a high PCE of 15.3% under 1 sun illumination. More excitingly, the stretchable device based on textured PDMS/PEDOT:PSS maintains a comparable PCE of 20.5% (20.8% for the rigid device) under indoor light illumination. Notably, the stretchable device is much more insensitive to the light direction, maintaining 38.5% of the initial PCE at an extremely small incident angle of 10° (16.3% for glass/ITO-based counterpart). The texturing stretchable substrate provides a new direction for achieving high performance and enhanced light utilization for the stretchable light-harvesting device, suitable for indoor and outdoor applications. 相似文献
1000.
Public adoption of policies detailed on government websites is an important topic in the field of e-government research, and researchers have mainly focused on the key factors that influence initial adoption. However, there has been much less discussion on factors influencing the continued use of government websites. This study identifies and tests a theoretical model that predicts consumers’ intentions to continue using government portals, using a mixed methods approach based on Grounded Theory. To construct a theoretical framework of public interest in continued use of government information portals, we interviewed 56 respondents and coded the interview data. Next, we tested the resulting model using data collected from a questionnaire-based survey of 354 users. The Structural Equation Modeling (SEM) results indicate that continued use is influenced by psychological perception, user characteristics, service parameters of the government portals and the government’s idea. Of these, psychological perception was found to have the strongest effect. These findings enrich the theoretical system of e-government public adoption of intention and have important practical significance for the development of Chinese government portals. 相似文献