承插型盘扣式支撑架在地铁车辆段工程中的应用

盘扣式支撑架具有承载力强、方便安全、结实耐用等优点,被广泛应用于地铁施工。本文以广州市轨道交通十八号线万顷沙车辆段为例,对承插型盘扣式支撑架在地铁车辆段工程中的具体应用进行了详细说明,以期为同类工程提供参考。     

2种侧围加强内框总成检具结构对比分析

概述了侧围加强内框总成与周边零件的匹配关系,从检具操作的人机工程出发,描述了侧围加强内框总成检具的2种定位方式和结构设计,对比了2种定位方式对于检测结果的影响,总结了其优点和弊端,结果表明侧围加强内框总成检具采用车内方向朝下的定位方式效果更好。     

破损水文观测孔涌水封堵技术在高河矿的应用

针对高河矿奥灰水文观测孔空水管锈蚀断裂漏水严重的问题,分析了存在的问题,制定了钻孔涌水封堵技术方案及相应的注浆施工工艺,并进行了为期7天的井下试验。封堵注浆压力达到6 MPa,使用注浆水泥50 t,水泥浆液凝固良好,注浆阀门打开后无出水现象。     

一种基于FPGA的可变速率帧结构设计与实现

在简述V.35接口的基础上针对V.35接口速率可变的应用需求提出了一种速率可变的帧结构,该帧结构可支持N×64kb/s(3≤N≤32)速率,从而在V.35接口上实现了多种速率的低速业务传输.     

复杂膨胀性围岩条件下交岔点支护技术研究

针对复杂膨胀性围岩条件下交岔点高应力集中区围岩稳定性控制和支护技术难题，通过对交岔点围岩变形表现形式、交岔点围岩变形机理的研究分析，提出了交岔点支护难点及重点。基于围岩控制理论分析，提出了“有限让压的柔性支护+全断面封闭抗压的刚性支护技术”，前期柔性支护采用“高强、高预应力锚杆+锚索+喷浆”联合支护有限度控制围岩变形，允许围岩在可控范围内释放围岩应力|后期通过架设异形支架与支撑架组成的联合支护体并喷射混凝土对交岔点围岩进行全断面封闭抗压支护，有效控制巷道交岔点围岩的变形。确保了交岔点围岩变形的整体可控性、稳定性，达到了预期支护效果。     

埋地管道泄漏内封堵装置设计与研究

针对流体输送埋地管道泄漏问题,设计了一种利用管道机器人携带封堵气囊进行快速应急封堵修复的埋地管道泄漏内封堵装置。采用矩阵变换方法建立了牵引系统驱动轮过弯方程,利用MATLAB软件对过弯方程进行了验证,同时利用ADAMS软件仿真分析过弯路径与驱动轮转角对牵引系统行走速度的影响。研究结果表明:由两个串联封堵器组成的应急封堵系统可满足复杂工况下的管道泄漏封堵要求;牵引系统驱动轮在弯管内部行走时,单轮速度呈周期性变化,但三个驱动轮整体周期运动特性一致;驱动轮转角在25°~40°时,牵引系统行走速度与驱动轮转角成正比,且转角为30°时驱动效果最好。该内封堵装置的结构设计可为管道泄漏应急封堵领域装备的研发提供重要参考。     

无源光网络标准发展及关键技术研究

无源光网络(Passive Optical Network,PON)作为当今接入网的主要技术解决方案,具有带宽使用效率高、传输距离远、抗干扰能力强等特点.通过研究PON技术的发展动态,本文首先归纳了各种PON技术的产生背景和应用特点,整理出各技术间的连接关系及主要标准;其次介绍了PON技术的帧结构,并对带宽、波长、传输模式等PON技术的主要参数进行了汇总;然后将国内外研究热点进行划分,围绕媒体访问控制协议、帧结构、动态带宽分配算法、节能机制等关键技术,阐述了其研究现状及在PON中的重要作用;最后对PON技术的发展趋势进行了展望.     

采油树平板闸阀柔性密封圈结构优化设计

为了提高采油树平板闸阀密封圈的密封性能,在泛塞封的基础上,设计一种密封圈本体唇边开有锯齿状凸起的新型柔性密封结构;运用有限元分析方法模拟密封圈的工作状况,分析柔性密封结构特性参数对密封圈密封性能的影响,获得不同柔性密封圈结构参数下密封面间接触应力分布规律,并对新型密封结构进行优化。结果表明:密封面间最大接触应力随唇边锯齿数量、唇边夹角度数的增大而增大,随唇谷夹角度数的增大而减小;新型密封结构选择锯齿数量为3、唇边夹角为20°、唇谷夹角为30°的特性参数时,其最大接触应力比常规Y形密封圈提高了15倍;新型柔性密封结构的密封圈与阀杆、阀盖壁面间接触应力比常规Y形密封圈有显著提高,提高了密封圈的密封性能。     

Characteristics and nutritional value of biscuits fortified with debittered salmon (Salmo salar) frame hydrolysate

Effect of debittered salmon frame hydrolysate (DSFH) at various levels (0, 5, 10, 15, 20 and 25 g/100 g) on physicochemical, textural, sensory and nutritional properties of biscuits was investigated. The highest thickness was obtained for the sample with 25 g/100 g DSFH (P < 0.05). There was no difference in diameter among all the biscuit samples (P > 0.05). The samples added with DSFH had lower weight, water activity and moisture content than the control (CONT, without DSFH) (P < 0.05). DSFH at 15 g/100 g showed no detrimental effect on sensory properties of resulting biscuits (DSFH-15). The DSFH-15 biscuit showed reduction in cutting force and fracturability. Scanning electron microscopic and cross-sectional images showed that DSFH-15 biscuit had more porous structure, compared to the CONT. The biscuits fortified with 15 g/100 g DSFH had higher protein but had lower energy value, fat and carbohydrate content than the CONT.     

Chromophore-Free Sealing and Repair of Soft Tissues Using Mid-Infrared Light-Activated Biosealants

Poor strength, infection, leakage, long procedure times, and inflammation limit the efficacy of common tissue sealing devices in surgeries and trauma. Light-activated sealing is attractive for tissue sealing and repair, and can be facilitated by the generation of local heat following absorption of nonionizing laser energy by chromophores. Here, the inherent ability of biomaterials is exploited to absorb nonionizing, mid-infrared (midIR) light in order to engender rapid photothermal sealing and repair of soft tissue wounds. In this approach, the biomaterial simultaneously acts as a photothermal convertor as well as a biosealant, which dispenses the need for exogeneous light-absorbing nanoparticles or dyes. Biomechanical recovery, mathematical modeling, histopathology analyses, tissue strain mapping using digital imaging correlation, and visualization of the biosealant-tissue interface using hyperspectral imaging indicate superior performance of midIR sealing in live mice compared to conventional sutures and glue. The midIR-biosealant approach demonstrates rapid sealing of soft tissues, improves cosmesis, lowers potential for scarring, obviates safety concerns because of the nonionizing light used, and allows adoption of a wide diversity of biomaterials. Taken together, the studies demonstrate a novel advance both in biomaterials for surgical sealing along with the use of nonionizing midIR light, with high potential for clinical translation.