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61.
White organic light‐emitting diodes (OLEDs) hold great promise for applications in displays and lighting due to high efficiency and superior white color balance. However, further improvement in efficiency remains a continuous and urgent demand due to limited energy flow extraction. A powerful method for drastically releasing the trapped energy flow in conventional white OLEDs is demonstrated by implementing unique quasi‐periodic subwavelength nanofunnel arrays (NFAs) via soft nanoimprinting lithography, which is ideal for enhancing light extraction without any spectral distortion or angular dependence. The resulting efficiency is over 2 times that of a conventional OLED used as a comparison. The external quantum efficiency and power efficiency are raised to 32.4% and 56.9 lm W?1, respectively. Besides, the substantial increase in efficiency over a broad bandwidth with angular color stability, the experimental proofs show that the NFA‐based extraction structure affords the enticing capacity against scrubbing and the self‐cleaning feature, which are critical to the commercial viability in practical applications.  相似文献   
62.
谢枭  胡飞  周军  康弘俊 《通信技术》2015,48(5):524-529
短波宽带波形是现代短波通信的最新研究成果,短波信道时变多径传播效应会产生严重的码间干扰(ISI),必须采用均衡技术消除ISI。迭代均衡技术(Turbo均衡)将信号检测技术和译码技术结合起来,比传统判决反馈均衡(DFE)技术具有更强抗ISI能力。研究了短波宽带波形Turbo均衡技术,提出了一种低复杂度的迭代检测方法用于短波宽带波形,仿真结果表明,在短波差信道条件下,Turbo均衡比DFE均衡的性能增益超过1.5 dB。  相似文献   
63.
64.
Particle replication in nonwetting templates (PRINT) is a continuous, roll‐to‐roll, high‐resolution molding technology which allows the design and synthesis of precisely defined micro‐ and nanoparticles. This technology adapts the lithographic techniques from the microelectronics industry and marries these with the roll‐to‐roll processes from the photographic film industry to enable researchers to have unprecedented control over particle size, shape, chemical composition, cargo, modulus, and surface properties. In addition, PRINT is a GMP‐compliant (GMP=good manufacturing practice) platform amenable for particle fabrication on a large scale. Herein, we describe some of our most recent work involving the PRINT technology for application in the biomedical and material sciences.  相似文献   
65.
通过静电纺丝技术制备了多孔软硬磁Ni0.5Zn0.5Fe2O4/SrFe12O19复合纤维,利用综合热重分析仪(TG-DSC)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线能谱仪(EDS)和矢量网络分析仪(VNA)等对复合纤维的晶体结构、微观形貌和电磁性能进行了表征,研究了不同软硬磁质量比对纤维结构和性能的影响。结果表明:900℃下制备的复合纤维具有立体多孔结构,软硬磁质量比为1∶3时,复合纤维的比表面积达到55 m2·g-1。吸波性能测试结果显示,当吸波剂涂层厚度为3.5 mm时,复合纤维在10.6 GHz处反射损失(RL)值达到-31.9 dB,在2~18 GHz频率范围内,RL值小于-10 dB的吸收带宽达到10.5 GHz,覆盖了整个X波段(8.2~12.4 GHz)和Ku波段(12.4~18 GHz),显示出优异的宽波段吸收性能。  相似文献   
66.
67.
Molecular dynamics in the soft crystal, E phase of 6-octyl-2-phenylazulene was studied by X-ray diffraction, and dielectric and Fourier transform infrared spectroscopies. Clear dielectric dispersion is observed due to the head-to-tail disordering in a kHz range around 400 K. The CH stretching frequencies exhibit more pronounced shifts at the phase transition point from the high-temperature ordered crystal to the E phase than that at the melting from the E phase to the isotropic liquid. The results are discussed in comparison with a typical E series, 4-n-alkyl-4′-isothiocyanatobiphenyl (n being the number of carbon atoms in the alkyl group).  相似文献   
68.
The fluorinated compound, (S)-4′′-(6-perfluoropentanoyoxyhexyl-1-oxy)-2′,3′-difluoro-4-(1-methylheptyloxycarbonyl)-[1,1′:4′,1′′]-terphenyl, which exhibits antiferroelectric SmCA*, ferroelectric SmC* and paraelectric SmA* phases, has been investigated by polarising optical microscopy, differential scanning calorimetry, X-ray diffraction and frequency-dependent dielectric spectroscopy methods. X-ray studies have revealed that the layer thickness remains almost constant in the SmA* phase but within the SmC* and SmCA* phases it decreases with decreasing temperature, a step jump being observed only at the SmA*–SmC* transition. The tilt angle in the SmCA* phase decreases from 22.2° to 19.5°, and in the SmC* phase it decreases from 18.8° to 5.5°. Spontaneous polarisation is found to be quite high and varies between 74.1 and 118.7 nC cm?2. The variation in ε′ and ε′′ with temperature shows a discontinuous change at the transition temperatures. Goldstone mode relaxation is only observed in the ferroelectric and antiferroelectric phases and is found to be of the Cole–Cole type. The soft mode is observed on application of a bias field near the SmC*–SmA* transition. Neither the soft mode nor the anti-phase azimuthal angle fluctuation mode is observed in SmCA*. Rotational viscosity decreases quite rapidly with temperature but in a different manner in the ferroelectric and antiferroelectric phases. Activation energy for this process is found to be 48.14 kJ mol?1 in the SmC* phase.  相似文献   
69.
Diffusiophoresis phenomenon of aoft particles suspended in binary electrolyte solutions is explored theoretically in this study based on the spherical cell model, focusing on the chemiphoresis component in absence of diffusion potential. Both the electrostatic and hydrodynamic aspects of the boundary confinement, or steric effect, due to the presence of neighboring particles are examined extensively under various electrokinetic conditions. Significant local extrema are found in mobility profiles expressed as functions of the Debye length in general, synchronized with the strength of the motion-inducing double layer polarization. Moreover, a seemingly peculiar phenomenon is observed that the soft particles may move faster in more concentrated suspensions. The competition between the simultaneous enhancement of the motion-inducing electric driving force and the motion-retarding hydrodynamic drag force from the boundary confinement effect of the neighboring particles is found to be responsible for it. The above findings are also demonstrated experimentally in a very recent study on the diffusiophoretic motion of soft particles through porous collagen hydrogels. The results presented here are useful in various practical applications of soft particles like drug delivery.  相似文献   
70.
Antiphospholipid syndrome (APS) is an autoimmune disease characterized by the production of β2-glycoprotein I (β2GPI)-dependent autoantibodies, with vascular thrombosis or obstetrical complications. Around 20% of APS patients are refractory to current treatments. Crassolide, a cembranoid diterpene extracted from soft corals, is a potential therapeutic candidate. Here, to examine the anti-inflammatory properties of crassolide, we first determined its effects on bone marrow-derived and splenic dendritic cells (DC). Specifically, we applied lipopolysaccharide (LPS) or β2GPI stimulation and measured the expressions of CD80 and CD86, and secretions of cytokines. We also determined in the OT-II mice, if bone marrow-derived DC was able to stimulate antigen-specific T cells. Moreover, we examined the therapeutic potential of crassolide postimmunization in a murine model of APS that depended on active immunization with β2GPI. The vascular manifestations were evaluated in terms of fluorescein-induced thrombi in mesenteric microvessels, whereas the obstetric manifestations were evaluated based on the proportion of fetal loss after pregnancy. We also measured blood titers of anti-β2GPI antibody, splenic cell proliferative responses and cytokine secretions after β2GPI stimulation ex vivo. Finally, we determined in these mice, hematological, hepatic and renal toxicities of crassolide. Crassolide after LPS stimulation suppressed DC maturation and secretion of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-12 and IL-23, and downstream T cell activation. Crassolide could partially ameliorate both the vascular and obstetric manifestations of APS in BALB/c mice. Both blood titers of anti-β2GPI antibody and splenic cell proliferation after β2GPI stimulation were reduced. Splenic Th1 and Th17 responses were also lowered after β2GPI stimulation. Finally, within therapeutic doses of crassolide, we found no evidence of its toxicity. In conclusion, we showed the ability of crassolide to suppress DC and downstream T cell responses. Crassolide is therefore a potential candidate for adjunctive therapy in APS.  相似文献   
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