Flexible Osteogenic Glue as an All-In-One Solution to Assist Fracture Fixation and Healing

Osteogenic glue that reproduces the natural bone composition represents the final frontier of orthopedic adhesives with the potential to revolutionize surgical strategies against comminuted fractures. However, it is difficult to achieve an all-in-one formula, which could provide flexible and reliable adhesiveness while avoiding interfering with or even promoting the healing of glued fractures. Herein, an osteogenic glue characterized by inorganic-in-organic integration between amine-modified mesoporous bioactive glass nanoparticles (AMBGN) and bioadhesive gelatin-dextran network (GelDex) is introduced as an all-in-one tool to flexibly adhere and splice bone fragments and subsequently guide fracture healing during degradation. Relying on such integration, a 4-fold improvement in cohesiveness is presented, followed by a nearly 5-fold enhancement in adhesive strength in ex vivo porcine bone samples. The reversible and re-adjustable adhesiveness also enables glue to effectively splice intricate fragments from highly comminuted fractures in the rabbit radius in an in vivo environment. Moreover, well-preserved organic–inorganic integrity during degradation of the glue guides sustained interfacial osteogenesis and achieve satisfying healing outcomes in glued fractures, as observed by the 2-fold improvement in biomechanical and radiological performance compared with commercially available cyanoacrylate adhesives. The current findings propose an all-in-one solution for the fixation of bone fragments during surgery.     

Efficiency Breakthrough of Fluorescence OLEDs by the Strategic Management of “Hot Excitons” at Highly Lying Excitation Triplet Energy Levels

Aggregation-induced emission (AIE) and hybridized local and charge-transfer (HLCT) materials are two kinds of promising electroluminescence systems for the fabrication of high-efficiency organic light-emitting diodes (OLEDs) by harnessing “hot excitons” at the high-lying triplet exciton states (T_n, n ≥ 2). Nonetheless, the efficiency of the resulting OLEDs did not meet expectations due to the possible loss of T_n→T_n−1. Herein, experimental results and theoretical calculations demonstrate the “hot exciton” process between the high-lying triplet state T₃ and the lowest excited singlet state S₁ in an AIE material 4⁗-(diphenylamino)-2″,5″-diphenyl-[1,1″:4′,1″:4″,1′″:4′″,1⁗-quinquephenyl]-4-carbonitrile (TPB-PAPC) and it is found that the Förster resonance energy transfer (FRET) between two molecules can facilitate the “hot exciton” process and inhibit the T₃→T₂ loss by doping a blue fluorescent emitter in TPB-PAPC. Finally, the doped TPB-PAPC blue OLEDs achieve a maximum external quantum efficiency (EQE_max) of 9.0% with a small efficiency roll-off. Furthermore, doping the blue fluorescent emitter in a HLCT material 2-(4-(10-(3-(9H-carbazol-9-yl)phenyl)anthracen-9-yl)phenyl)-1-phenyl-1H-phenanthro[9,10-d] imidazole (PAC) is used as the emission layer, and the resulting blue OLEDs exhibit an EQE_max of 17.4%, realizing the efficiency breakthrough of blue fluorescence OLEDs. This work establishes a physical insight in the design of high-performance “hot exciton” molecules and the fabrication of high-performance blue fluorescence OLEDs.     

基于副载波复用的多输入单输出正交频分复用LED可见光通信系统

提出了一种基于副载波复用的新型的多输入单输出(MISO)正交频分复用可见光通信(OFDM-VLC)系统构架,并且实验验证了2×1和3×1的MISO OFDM-VLC系统传输。分别测量了2×1和3×1的实验系统的误差矢量幅度(EVM)随输入电压变化的曲线图,找出了两个系统各自的最佳偏置范围。在将输入电压设置在最佳偏置范围之内的情况下,改变传输距离,对2×1系统,给出了系统EVM性能变化的曲线图;对3×1系统,给出了系统EVM和误码率(BER)性能变化的曲线图。在没有任何均衡的情况下,两个系统的传输距离都可以长达140cm。     

高功率超短激光脉冲特性的三阶相关测量

为了准确测量皮秒量级超短脉冲的信噪比,扩大测量仪器的可测动态范围,针对高功率超短激光脉冲在相关过程中产生参量荧光的问题,研制了一台重复频率扫描测量的三阶相关仪,并在皮秒域短脉冲光学参量啁啾脉冲放大(OPCPA)抽运源上开展了测量技术研究。研究实验表明,通过采用大角度非共线匹配方式,消除了参量荧光对测量过程的影响,进而通过结构优化降低了背景噪声的影响,使可测动态范围达到107左右。由于互相关技术的非对称性,该测量系统可同时提供时间波形的分析功能。测量结果显示,激光脉冲前沿与双曲正割(sech)型曲线比较吻合,而脉冲后沿与高斯型曲线吻合得比较好。     

硅探测器加工中的离子注入工艺设计与控制

应用离子注入工艺可制备获得线性电流大、窗口死层薄的硅pin辐射探测器。首先简要介绍了离子注入工艺形成pn结的原理,重点根据技术要求进行了离子注入工艺设计和计算,分别得到了注入能量为40 keV和注入剂量为4×1014/cm2的两个重要控制参数。同时分析了在离子注入工艺中存在的影响因素和相应处理方法,对生产具有良好的指导作用。采用所设计的工艺参数制备获得的硅pin辐射探测器各项技术指标均满足要求,验证了离子注入工艺设计与参数控制的有效性。     

A High Energy Density Asymmetric Supercapacitor from Nano‐architectured Ni(OH)2/Carbon Nanotube Electrodes

The demand for advanced energy storage devices such as supercapacitors and lithium‐ion batteries has been increasing to meet the application requirements of hybrid vehicles and renewable energy systems. A major limitation of state‐of‐art supercapacitors lies in their relatively low energy density compared with lithium batteries although they have superior power density and cycle life. Here, we report an additive‐free, nano‐architectured nickel hydroxide/carbon nanotube (Ni(OH)₂/CNT) electrode for high energy density supercapacitors prepared by a facile two‐step fabrication method. This Ni(OH)₂/CNT electrode consists of a thick layer of conformable Ni(OH)₂ nano‐flakes on CNT bundles directly grown on Ni foams (NFs) with a very high areal mass loading of 4.85 mg cm^?2 for Ni(OH)₂. Our Ni(OH)₂/CNT/NF electrode demonstrates the highest specific capacitance of 3300 F g^?1 and highest areal capacitance of 16 F cm^?2, to the best of our knowledge. An asymmetric supercapacitor using the Ni(OH)₂/CNT/NF electrode as the anode assembled with an activated carbon (AC) cathode can achieve a high cell voltage of 1.8 V and an energy density up to 50.6 Wh/kg, over 10 times higher than that of traditional electrochemical double‐layer capacitors (EDLCs).     

Qualitative analysis for recurrent neural networks with linear threshold transfer functions

Multistable networks have attracted much interest in recent years, since multistability is of primary importance for some applications of recurrent neural networks where monostability exhibits some restrictions. This paper focuses on the analysis of dynamical property for a class of additive recurrent neural networks with nonsaturating linear threshold transfer functions. A milder condition is derived to guarantee the boundedness and global attractivity of the networks. Dynamical properties of the equilibria of two-dimensional networks are analyzed theoretically, and the relationships between the equilibria features and network parameters (synaptic weights and external inputs) are revealed. In addition, the sufficient and necessary conditions for coexistence of multiple equilibria are obtained, which confirmed the observations in with a cortex-inspired silicon circuit. The results obtained in this paper are applicable to both symmetric and nonsymmetric networks. Simulation examples are used to illustrate the theory developed in this paper.     

移动智能网系统及其在我国的发展

与移动网的结合是智能网研究的新方向。ＥＴＳＩ提出的ＣＡＭＥＬ方案用来在ＧＳＭ网络中提供智能业务。北京邮电大学程控交换与通信网国家重点实验室在其已成功应用的固定智能网ＣＩＮ０２系统的基础上,参照ＣＡＭＥＬ方案推出了ＣＭＩＮ０２移动智能网系统。现在该系统可提供预付费业务、移动虚拟专用网业务和通用接入码业务。     

MPEG-4及其在VOD业务中的应用

本文介绍视频点播（ Ｖ Ｏ Ｄ） 业务和 Ｍ Ｐ Ｅ Ｇ ４ 国际最终标准草案的主要内容,分析了 Ｍ Ｐ Ｅ Ｇ ４ 标准在 Ｖ Ｏ Ｄ 业务中的应用,指出 Ｍ Ｐ Ｅ Ｇ ４ 将成为未来 Ｖ Ｏ Ｄ 系统的主要编码标准。     

TFT-LCD技术的研究进展与发展趋势

介绍了近年来世界ＴＦＴ ＬＣＤ技术的研究现状,论述了未来ＴＦＴ ＬＣＤ技术的发展趋势