改善氧化铝短纤维与铝液基体间浸润性的研究

提出通过基体合金化改善Al2 O3(sf) /Al界面浸润性的想法 ,添加的合金元素M须满足以下两个条件 :(1 )元素M的表面能必须小于Al的 ,即ΓM<ΓAl;(2 )元素M的氧化物生成Gibbs自由能要小于氧化铝的。在试验中得以验证 ,元素Mg是一种良好的润湿增强剂 ,稀土元素La可在Mg的基础上进一步增强其润湿性 ,但未发现其在界面上生成任何反应产物     

The Effect of Surface-Active Phospholipids on the Lubrication of Osteoarthritic Sheep Knee Joints: Friction

The synovial fluid aspirate from human joints that have experienced serious traumatic injury has been shown to have lower concentrations of phospholipids when compared with healthy joints. Previous studies provide evidence that synovial fluid constituents, specifically dipalmitoyl phosphatidylcholine (L&lt;img src="/content/j47p6435l412534q/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-DPPC), are highly surface active, capable of rapidly depositing a layer of phospholipids onto glass. Such research has demonstrated that the adsorbed surface layers of synovial surfactant are excellent lubricants in vitro, significantly reducing the coefficient of friction under physiological loading in human knee joints. This study aimed to investigate the effect of concentration of L&lt;img src="/content/j47p6435l412534q/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-DPPC lubricant solutions on the coefficient of friction of worn articular cartilage on steel. A pin-on-disc apparatus was used to measure the coefficient of friction of sheep-knee articular cartilage on steel under unidirectional sliding at physiological conditions of load and speed. Concentrations of L&lt;img src="/content/j47p6435l412534q/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-DPPC solution between 100 times less and 100 times more than is normally present in synovial fluid were tested. All specimens were tested following a period of unlubricated induced wear. Trials were carried out at ambient temperature and between 33–37°C (representative of in vivo joint temperature). Friction measurement results demonstrated a reduction in the coefficient of friction of worn articular cartilage against steel with increasing concentrations of L&lt;img src="/content/j47p6435l412534q/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-DPPC in lubricant solution.     

A Biomimetic Mussel‐Inspired ε‐Poly‐l‐lysine Hydrogel with Robust Tissue‐Anchor and Anti‐Infection Capacity

In situ hydrogels have attracted considerable attention in tissue engineering because of their minimal invasiveness and ability to match the irregular tissue defects. However, hydrous physiological environments and the high level of moisture in hydrogels severely hamper binding to the target tissue and easily cause wound infection, thereby limiting the effectiveness in wound care management. Thus, forming an intimate assembly of the hydrogel to the tissue and preventing wound infecting still remains a significant challenge. In this study, inspired by mussel adhesive protein, a biomimetic dopamine‐modified ε‐poly‐l ‐lysine‐polyethylene glycol‐based hydrogel (PPD hydrogel) wound dressing is developed in situ using horseradish peroxidase cross‐linking. The biomimetic catechol–Lys residue distribution in PPD polymer provides a catechol–Lys cooperation effect, which endows the PPD hydrogels with superior wet tissue adhesion properties. It is demonstrated that the PPD hydrogel can facilely and intimately integrate with biological tissue and exhibits superior capacity of in vivo hemostatic and accelerated wound repair. In addition, the hydrogels exhibit outstanding anti‐infection property because of the inherent antibacterial ability of ε‐poly‐l ‐lysine. These findings shed new light on the development of mussel‐inspired tissue‐anchored and antibacterial hydrogel materials serving as wound dressings.     

应用于自由空间光通信的PIN激光信号阵列接收器

针对目前的自由空间光通信存在空间光-光纤难以 有效耦合这一问题,考虑到空间光耦合进入光纤后需要将光信号转换为电信号才能实现通信 ,为此本 文提出直接将空间光信号转换为电信号的思想,设计了一种应用于空间光通信的PIN光电二 极管阵列接收器,每一个PIN光电二极管可 以独立接收空间激光并将其转换为电信号,多个PIN光电二极管通过串联和并联将电信号汇 合以方便后续信号处理。对这一新的接收器进行理论分析和模拟实验的结果表明,新的接收 器能有效提高空间光的接收效率。     

Influence of microstructure of lactone‐based triblock copolymers on drug release behavior of their microspheres

The current work focuses on the influence of microstructure of different lactone‐based triblock copolymers on drug delivery, where the middle segment was δ‐valerolactone or ?‐caprolactone and the terminal segment was d ,l ‐lactide or &lt;i>cis &lt;/i>‐lactide. Microspheres were fabricated from the triblocks using salicylic acid as the model drug. The microsphere formation and drug release were investigated by scanning electron microscopy, ultraviolet–visible spectroscopy, X‐ray diffraction, and thermogravimetry. The size of the microspheres ranged from 2 to 20 µm in diameter. The diffusion coefficient values showed that replacement of the middle segment, δ‐valerolactone with ?‐caprolactone, retarded the diffusion of the drug molecules. The diffusion coefficient was lowered when d ,l ‐lactide content was decreased in the triblock. Mathematical models were used to predict the drug release from the microspheres of different triblocks. The modeling study on drug release profiles revealed that the biodegradable nature of the triblock played a crucial role in determining the drug release kinetics. The diffusion and degradation reaction justified the drug release from microsphere. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , &lt;i>134 &lt;/i>, 45284.     

国外地下自卸汽车的发展

介绍了国外地下自卸汽车的主要生产企业以及其产品特点、技术性能与发展方向。     

鄂尔多斯盆地煤储层低温氮吸附孔隙分形特征研究

在利用低温氮吸附法测试鄂尔多斯盆地煤储层孔隙分布的基础上 ,计算了煤样的孔容及比表面分维数 ,并分析了煤储层对甲烷的吸附能力与孔隙分维之间的关系。研究表明随着比表面分维数的增加 ,煤储层兰氏体积减小 ,而兰氏压力增加 ,随着孔容分维数的增加兰氏体积减小。     

聚d,l-乳酸及其对20 毫米断缺神经诱导修复的研究

报道了聚－d,l-乳酸在大鼠体内的降解，以及用聚d,l-乳酸制备的神经诱导管对大鼠坐骨神经20mm断缺修复的研究，通过肉眼观察，组织学检查，电镜观察，以及电生理测定等方法和手段，对神经诱导再生过程进行了跟踪，揭示了随着神经的再生聚d,l-乳酸管形态的变化，且对神经修复的效果进行了评价，研究表明：用聚d,l-乳酸管可成功地诱导20m断缺神经得到再生修复。     

Simultaneous Territories: Unveiling the Geographies of Latin American Cities

The harmonious, utopian image that housing in Latin America exuded across the world in the postwar years is very much at odds with the current view of the region, in which unbridled shantytowns dominate. Patricio del Real sets out to understand how such a rupture might have been possible: What was the process of exclusion at play in these Modernist projects? How does Modernism represent simultaneous territories in which emerging challenges to the social and political status quo were merely muffled by the architectural seduction of the 1950s?. Copyright © 2011 John Wiley & Sons, Ltd.     

EFFECT OF NUCLEOTIDE SEQUENCE ON THE BINDING OF (–)–ANTI–DIBENZO– [a,l]PYRENE–11,12–DIOL 13,14–EPOXIDE TO SHORT OLIGODEOXYRIBONUCLEOTIDES

&lt;b>Abstract&lt;/b>&lt;/p> Seven selfcomplementary decamer oligodeoxyribonucleotides were reacted with (–)–&lt;i>anti&lt;/i>–(11&lt;i>R&lt;/i>,12&lt;i>S&lt;/i>)–dihydrodiol (13&lt;i>S&lt;/i>,14&lt;i>R&lt;/i>)–epoxide of dibenzo[&lt;i>a,l&lt;/i>]pyrene (DB[&lt;i>a&lt;/i>,&lt;i>l&lt;/i>]PDE). The oligodeoxyribonucleotides were postlabeled with &lt;sup>33&lt;/sup>P–ATP, digested to mononucleotides and the amount of adducts formed was determined by HPLC. We found that the nucleotide sequence affects the binding of DB[&lt;i>a&lt;/i>,&lt;i>l&lt;/i>]PDE to DNA. DB[&lt;i>a&lt;/i>,&lt;i>l&lt;/i>]PDE binds better to GC rich oligodeoxyribonucleotides than to AT rich oligodeoxyribonucleotides. The CGC sequence binds more DB[&lt;i>a&lt;/i>,&lt;i>l&lt;/i>]PDE than GGC, TGC, GAT or AGC sequences. The reactions were carried out on ice or at 37°C. There was no evidence of temperature effects on the amount of DB[&lt;i>a&lt;/i>,&lt;i>l&lt;/i>]PDE binding.