Bone Plate Composed of a Ternary Nanohydroxyapatite/Polyamide 66/Glass Fiber Composite: Biocompatibility In Vivo and Internal Fixation for Canine Femur Fractures

Bone plates have been applied to fix fractures for over a hundred years. Metal plates are the gold standard. However, an increasing number of clinical practices and animal experiments have shown that metal plates have had incidents of failure due to their rigid fixation and long‐term complications. Degradable composites present the advantages of a lower elastic modulus and absorbable properties but are unsuitable for load‐bearing applications. Nondegradable bone plates composed of a nanohydroxyapatite/polyamide 66/glass fiber (n‐HA/PA66/GF) composite are prepared, which have enough strength and a low elastic modulus for an internal fixation device. To better assess its function as a bone plate, animal experiments are conducted using a canine load‐bearing femur fracture model. The results show that the n‐HA/PA66/GF plate can fix fractures effectively. Gross observation, radiographic films, and histological analysis all show that the n‐HA/PA66/GF plate leads to a secondary (indirect) union with obvious callus formation, whereas the titanium plate leads to primary (direct) union due to rigid fixation. Furthermore, the histological results reveal that new bone grows at the interface and that the n‐HA/PA66/GF plate can integrate with native bone tissue. Consequently, the n‐HA/PA66/GF composite shows good potential as a bone plate to fix loading‐bearing bone fractures.     

光电导及光反射法测量AlGaN薄膜的Al组分

ＡｌＧａＮ／ＧａＮ异质结兰光激光器和发光管近年来得到很大的发展．高速和高功率的ＡｌＧａＮ／ＧａＮ异质结场效应管（ＨＦＥＴ）的研究也得到很大的重视．ＡｌＧａＮ 薄层中的Ａｌ组分是决定此类器件的设计和性能的一个重要参量． 传统的测量组分的方法如ＸＰＳ和Ａｕｇｅｒ等方法需要大型的仪器,而且大多数方法是破坏性的,注意到ＡｌＧａＮ的禁带宽度Ｅｇ和Ａｌ组分有直接的关系,可以通过光学方法先测出Ｅｇ,用下式推算出Ａｌ的组分： Ｅｇ（ＡｌＧａＮ）＝ Ｅｇ（ＧａＮ）（１－ｘ）＋Ｅｇ（ＡｌＮ）ｘ－ｂｘ（１－ｘ）．其中ｘ是…     

基于盲信号分离算法的立体声回波抵消的研究

当处理混合语音信号时,传统的立体声回波抵消技术不具备修正参数的能力.因此,传统的立体声回波抵消技术对于信号传输的可靠性存在很大的问题,论文中,我们提出一种基于盲信号分离方法(BSS)的立体声回波抵消技术.在我们提出的系统中,我们通过分离回波信号和说话人的语音信号来达到移除回波信号的目的.结果证明,本方法对于传输信号的可靠性有明显的提高.     

Metabolic Regulation of Tumor Microenvironment with Biohybrid Bacterial Bioreactor for Enhanced Cancer Chemo-Immunotherapy

Immunogenic cell death (ICD) induced by specific chemotherapeutic agents is often hampered by the immunosuppressive tumor microenvironment (TME). Here, a bacterial bioreactor E@Fe-DOX, is developed, to enhance ICD-mediated antitumor immunity by in situ manipulation of tumor metabolism-immune interactions. The E@Fe-DOX bioreactor is constructed by depositing doxorubicin-loaded iron-polyphenol nanoparticles on Eubacterium hallii, which can specifically target hypoxic tumor regions and release doxorubicin and Fe³⁺ to induce ICD. In addition, Eubacterium hallii can continuously convert intratumoral lactate to butyrate, which inhibits the polarization of pro-tumoral M2-like macrophages and improves the function of tumor-infiltrating cytotoxic T cells. Furthermore, E@Fe-DOX promotes the formation of immune cell-aggregated tertiary lymph structures (TLS) to augment ICD-induced antitumor immunity. In murine tumor models, E@Fe-DOX significantly inhibits tumor growth and enhances immune checkpoint blockade (ICB) therapy. Overall, the developed living biomaterial offers a promising strategy to potentiate cancer chemo-immunotherapy by continuously regulating the intratumoral immuno-metabolic microenvironment.     

Deepening Insights into Aggregation Effect of Intermolecular Charge-Transfer Aggregates for Highly Efficient Near-Infrared Non-Doped Organic Light-Emitting Diodes over 780 nm

Though urgently needed, high-efficiency near-infrared (NIR) organic light-emitting diode (OLED) is still rare due to the energy-gap law. Formation of intermolecular charge-transfer aggregates (CTA) with nonadiabatic coupling suppression can decelerate non-radiative decay rates for high-efficiency NIR-OLEDs. However, the aggregation effect of CTA is still not fully understood, which limits the rational design of CTA. Herein, two CTA molecules with a same π-framework but different terminal substituents are developed to unveil the aggregation effect. In highly ordered crystalline states, the terminal substituents substantially affect the molecular packing motifs and intermolecular charge-transfer states, thus leading to distinct photophysical properties. In comparison, in amorphous states, these two CTA demonstrate similar photophysical behaviors and properties due to their similar molecular packing and intermolecular interactions as evidenced by molecular dynamics simulations. Importantly, the formations of amorphous CTA trigger multifunction improvements such as aggregation-induced NIR emission, aggregation-induced thermally activated delayed fluorescence, self-doping and self-host features. The non-doped OLEDs demonstrate NIR emissions centered at 788 and 803 nm, and high maximum external quantum efficiencies of 2.6% and 1.5% with small efficiency roll-off, respectively. This study provides deeper insight into the aggregation effect of CTA and lays a foundation for the development of high-efficiency NIR non-doped OLEDs.     

Ultraefficient Non-Doped Deep Blue Fluorescent OLED: Achieving a High EQE of 10.17% at 1000 cd m−2 with CIEy<0.08

The pursuit for efficient deep blue material is an ever-increasing issue in organic optoelectronics field. It is a long-standing challenge to achieve high external quantum efficiency (EQE) exceed 10% at brightness of 1000 cd m⁻² with a Commission International de L'Eclairage (CIE_y) <0.08 in non-doped organic light-emitting diodes (OLEDs). Herein, this study reports a deep blue luminogen, PPITPh, by bonding phenanthro[9,10-d]imidazole moiety with m-terphenyl group via benzene bridge. The non-doped OLED based on PPITPh exhibits an exceptionally high EQE of 11.83% with a CIE coordinate of (0.15, 0.07). The EQE still maintains 10.17% at the brightness of 1000 cd m⁻², and even at a brightness as high as 10000 cd m⁻², an EQE of 7.5% is still remained, representing the record-high result among non-doped deep-blue OLEDs at 1000 cd m⁻². The unprecedented device performance is attributed to the reversed intersystem crossing process through hot exciton mechanism. Besides, the maximum EQE of orange phosphorescent OLED with PPITPh as host is 32.02%, and remains 31.17% at the brightness of 1000 cd m⁻². Such minimal efficiency roll-off demonstrates that PPITPh is also an excellent phosphorescent host material. The result offers a new design strategy for the enrichment of high-efficiency deep blue luminogen.     

Properties of Indium-Doped ZnO Films Prepared in an Oxygen-Rich Plasma

Indium-doped zinc oxide (ZnO:In) films were prepared in an Ar:O₂ plasma by reactive magnetron sputtering. The x-ray diffraction (XRD) patterns presented the crystal structures of ZnO:In films, while transmission spectra and photoluminescence (PL) spectra showed the changed band gap and the visible emission from defects, as compared to the PL spectra of undoped ZnO films. It was concluded that the increase of substrate temperature enhanced the crystal quality of ZnO:In films; the incorporation of In made the c-axis constant of the samples larger than that of undoped ZnO films; the blue emission was due to the transition from an unknown donor level by indium doping to the valance band; and the orange-green emission originated from acceptor defects (O_Zn) formed in the O-rich plasma. Meanwhile, the current- voltage characteristics and persistent photoconductivity phenomenon also could be explained by the increased acceptor defects (O_Zn) that formed when the substrate temperature was increased.     

柠酸酸发酵废醪提取食用色素的研究

采用树脂法从柠檬酸废醪中提取食用色素—焦糖色素和黄色素。产品质量分别达到国家标准,同时使排放废液的ＣＯＤ由１０～１４万ｍｇ／ｌ降至１万ｍｇ／ｌ左右,ｐＨ由４．５～５．０升至７．０左右     

Augmentation of XNAV System to an Ultraviolet Sensor-Based Satellite Navigation System

X-ray pulsar-based navigation (XNAV) using one X-ray detector is investigated as an augmentation to the capability of an ultraviolet (UV) sensor-based satellite autonomous navigation system. The satellite state dynamics are analyzed to establish the dynamical equations of the satellite autonomous navigation system. A time transformation equation that accounts for relativistic effects is presented and the measurement model of the XNAV system is derived using pulse phase information from only one pulsar. The measurement model of the UV sensor-based satellite navigation system is presented using the Earth image information from the UV sensor. In order to integrate the measurements from the X-ray sensor and the UV sensor, a federated filter is developed to provide the optimal simultaneous estimation of position and velocity of the satellite. The concept is demonstrated on a GPS orbit and a geosynchronous orbit and it is found that the performance of the integrated satellite navigation system is improved with respect to that of the UV sensor-based satellite navigation system.     

CO-OFDM系统中一种新颖相位噪声抑制算法

针对相干光正交频分复用(CO-OFDM)系统中相位噪声造成的严重影响,提出了一种采用线性插值和卡尔曼滤波相结合的相位噪声抑制算法.该算法在第一阶中对接收端的时域信号进行线性组合,之后利用线性插值算法对相位噪声进行初步抑制,在第二阶中采用卡尔曼滤波技术来抑制残余的相位噪声.分析和仿真表明:提出的二阶算法能够有效地抑制相位噪声对OFDM符号的影响,在相位噪声线宽较大时明显地降低错误平层,利用所提出的二阶算法可使误码率达到10-7以下,有效地提高了系统的性能.