Fast full‐color reflective display via photoluminescent enhancement

Reflective displays are advantageous in applications requiring low power or daylight readability. However, there are no low‐cost reflective technologies capable of displaying bright colors. By employing photoluminescence to more efficiently use ambient light, we created a prototype display that provides bright, full color in a simple, low‐cost architecture. This prototype includes a novel electrokinetic shutter, a layer that incorporates patterned luminescent red, green, and blue sub‐pixel elements, and a novel optical out‐coupling scheme. The luminescent elements convert otherwise‐wasted portions of the incident spectrum to light in the desired color band, resulting in improved color saturation and lightness. This prototype provides a color gamut that is superior to competing reflective display technologies that utilize color filters in single‐layer side‐by‐side sub‐pixel architectures. The current prototype is capable of switching in <0.5 s; future displays based on an alternative electro‐optic shutter technology should achieve video rate operation. A transflective version of this technology has also been prototyped. The transflective version utilizes its backlight with a power efficiency that is at least three times that of a conventional liquid crystal display. These photoluminescence‐based technologies enable a host of applications ranging from low‐power mobile products and retail pricing signage to daylight readable signage for outdoor advertising segments.     

Output chattering attenuation between two tracking controllers

In this paper, an output chattering attenuation scheme is proposed for two tracking controllers. The controllers have integral actions and are used to eliminate the steady-state tracking errors. By designing a compensator and reducing the discontinuous switching, the output chattering at the switching points can be attenuated significantly. Moreover, combining with the generalized Kalman-Yakubovich-Popov (KYP) lemma and the parameter-dependent Lyapunov function method, this problem can be characterized in terms of linear matrix inequality (LMI) formulation. Finally, the simulation results demonstrate the effectiveness of the proposed method.     

半干污泥流量计量方法与装置的研究及应用

污泥经干化后进行焚烧已成为市政污泥处理的一种趋势,精确稳定控制进焚烧炉的半干污泥投加量是维持焚烧炉燃烧工况稳定的关键.因半干污泥具有颗粒度不均、黏性高、有弹性、有堆积空隙等固有特性,目前没有直接测量入炉半干污泥投加量的计量仪表,需要通过泵频率或计量装置间接控制入炉污泥量.针对半干污泥计量,研究了在半干污泥输送系统中加入计量槽装置,通过利用料斗内物料减少速率来计算半干污泥流量的计量方法,并给出了计量装置工作的控制过程.该方法在上海市某污泥干化焚烧工程中实际应用的结果表明,与常规的控制污泥输送螺旋频率来测量污泥流量的方法相比,该方法可以实现半干污泥量的精确自动控制,保持焚烧炉燃烧温度和工况相对稳定,取得了良好的效果.     

15%联苯菊酯·氟啶虫酰胺悬浮剂防治桃蚜药效试验

为明确15%联苯菊酯·氟啶虫酰胺悬浮剂对桃蚜的田间防效,2017—2018年分别在河南、河北、辽宁3省的不同桃园进行了药效试验。结果表明,15%联苯菊酯·氟啶虫酰胺悬浮剂有效剂量为33.3~37.5 mg/L时对桃蚜防效很好,药后7、14 d的防效均在90%以上,对所有供试桃树安全。建议最好在春季桃蚜初发期至初盛期喷洒用药。     

Importance of Low-Temperature Melt-Mixing on the Construction of Stereocomplex Crystallites with Superior Nucleation Efficiency in Asymmetric Poly(l-lactide)/Poly(d-lactide) Blends

The nucleation efficiency (NE) of stereocomplex crystallites (SCs) formed in asymmetric poly(L-lactide)/poly(D-lactide) (PLLA/PDLA) blends is generally unsatisfactory because the competition between stereocomplexation and chain mixing involved in the melt-mixing process can cause low formation efficiency and even severe aggregation of SCs. Herein, it is attempted to achieve high-efficient formation of finely dispersed SCs particles by designing a unique melt-mixing procedure, where the mixing of PLLA with 0.75 wt% PDLA is first performed at elevated temperatures (far above the melting temperature of SCs) to allow the homogeneous mixing of PLLA/PDLA chains and then at a low temperature (slightly above that of homocrystallites) to permit the full stereocomplexation of the premixed chains. It is found that the SCs formed in the blends exhibit unexpectedly low NEs (e.g., 54.5%), much inferior to that (73.6%) in the counterpart without undergoing premixing. This is because the introduction of premixing leads to a remarkable deterioration in the amount of SCs particles formed, despite decreased particle size, highlighting that the direct mixing at low temperatures of 170–180 °C (about 20–30 °C lower than that used in common melt-processing of PLA) is more effective for the construction of SCs with superior NE. The mechanisms for these striking findings are discussed.     

Effect and Evolution of Oxide Film in the HDH-Ti Powder Surface on Densification Behavior During Sintering

Metallurgical and Materials Transactions A - In this work, we used hydride-dehydride Ti (HDH-Ti) powders (with the oxygen levels of 0.17 and 0.51 wt pct, respectively) combined with microstructural...     

地聚合物混凝土配比及力学性能研究

混凝土是巷道支护过程中的重要建筑材料,然而混凝土在巷道施工中常常出现质量问题,为了不影响正常生产,需要对其进行修补。地聚合物混凝土凝结时间快,早期强度高,界面结合能力强,耐高温性和抗冻性强,耐腐蚀性良好,具有用作修补材料的潜力。以粉煤灰和矿粉为原料,Na₂SiO₃溶液和NaOH为碱激发剂制备地聚合物胶砂,研究不同的碱激发剂模数（1.0、1.2、1.4）和掺量（10%、15%、20%）对不同龄期胶砂力学性能的影响。结果表明：当碱激发剂模数为1.2,碱掺量为15%时,胶砂强度达到最大值。设计正交试验,研究了不同水胶比（0.45、0.50、0.55）、粉煤灰掺量（30%、50%、70%）和砂率（30%、35%、40%）对不同龄期地聚合物混凝土的工作性能和力学性能的影响。结果表明：粉煤灰掺量对抗压强度影响最为显著,水胶比次之,而砂率对强度发展几乎没有影响。最优的配合比为水胶比为0.50,粉煤灰掺量为50%,砂率为35%。     

一种并行工程信息集成框架的构建

本文针对现有的并行工程信息集成框架对并行工程只提供消极支持的问题展开讨论，通过技术域，支撑域，管理域三个域的建立与分析，特别是对ＣＦ积极支持方法进行探讨，提出一种推拉式的建模思想，实现对并行设计的监督和控制。并依此思想建立了一个ＣＥ信息集成框架。