喷嘴临界截面直径对喷射器性能影响实验研究

依据索科洛夫等学者提出的经验公式对喷射器进行优化设计,搭建了用于测量喷射器性能的实验台,以CO2为工质,分别研究当工作流体压力在8.0~9.6MPa、引射流体压力在2.4~2.8MPa以及工作流体温度在70~90℃时,喷嘴临界截面直径对喷射系数的变化规律。实验结果表明：当喷射器背压为3.9MPa、工作流体温度为90℃、引射流体压力为2.4MPa、工作流体压力在8.0~9.6MPa时,喷射器的喷射系数随喷嘴临界截面直径的增大而减小;当喷射器背压为3.9MPa、工作流体温度为90℃、工作流体压力为10.0MPa、引射流体压力在2.4~2.8MPa时,喷射器的喷射系数也随喷嘴临界截面直径的增大而减小;且喷射系数理论值与实验值吻合度较好,误差在±3.75%范围内。当喷射器工作流体压力为10.0MPa、引射流体压力为2.7MPa、喷射器背压为3.9MPa、工作流体温度在70~90℃时,喷射系数随着喷嘴临界截面直径的增大而逐渐减小。另外,在保持喷射器的基本工作参数不变时,工作流体压力及引射流体压力的提高对喷射器喷射系数均有提升作用。     

基于多因素的城市燃气管道泄漏警戒区域模拟研究

以城市燃气管道泄漏应急救援警戒范围为研究对象,建立区域典型场景,设置管道压强、泄漏时长、风速、气温、日照辐射强度等5组单变量场景组合,模拟管道破损、可燃气体泄漏扩散行为.提出将影响范围"稳态到达时间"与影响范围大小一并作为特征指标,分析不同变量对特征指标的影响.结果表明,在各单变量场景组内,吸入毒性范围值最小;易燃范围...     

Comprehensive Analysis of Combinatorial Pharmacological Treatments to Correct Nonsense Mutations in the CFTR Gene

Cystic fibrosis (CF) is caused by loss of function of the CFTR chloride channel. A substantial number of CF patients carry nonsense mutations in the CFTR gene. These patients cannot directly benefit from pharmacological correctors and potentiators that have been developed for other types of CFTR mutations. We evaluated the efficacy of combinations of drugs targeting at various levels the effects of nonsense mutations: SMG1i to protect CFTR mRNA from nonsense-mediated decay (NMD), G418 and ELX-02 for readthrough, VX-809 and VX-445 to promote protein maturation and function, PTI-428 to enhance CFTR protein synthesis. We found that the extent of rescue and sensitivity to the various agents is largely dependent on the type of mutation, with W1282X and R553X being the mutations most and least sensitive to pharmacological treatments, respectively. In particular, W1282X-CFTR was highly responsive to NMD suppression by SMG1i but also required treatment with VX-445 corrector to show function. In contrast, G542X-CFTR required treatment with readthrough agents and VX-809. Importantly, we never found cooperativity between the NMD inhibitor and readthrough compounds. Our results indicate that treatment of CF patients with nonsense mutations requires a precision medicine approach with the design of specific drug combinations for each mutation.     

冷气掺混对涡轮叶栅气动性能影响试验研究

为分析冷气掺混对涡轮叶栅气动性能的影响,对某船用燃气轮机高压涡轮导叶开展了带冷气条件下的扇形叶栅吹风试验,结果表明：冷气掺混对叶片型面压力分布有较大影响,且在吸力面表现尤为突出;在冷气流量比小于7%工况下,叶栅能量损失较无冷气喷射时增加（< 9%）,甚至在Ma=1.05时能量损失较无冷气喷射时还小;当冷气流量比大于7%时,叶栅能量损失随冷气流量比的增大而迅速增加（最大可达26%）;平均出口气流角随着出口马赫数的增加而增大,变化范围为17.7°~18.1°,且在同一工况下冷气喷射会使平均出口气流角增大。     

卷接机烟支高速剔除问题解决办法

从电控原理和剔除动作的各执行环节深入分析了卷接机组高速剔除时存在的问题及其原因,并针对问题从电磁阀、气路配置、加速开关级和控制信号等各方面,提出了解决问题的具体方法。高速剔除问题的解决,对保证设备的正常运行和提高产品质量均有重要作用。本文介绍的方法对解决不同型号的卷接机组的高速剔除问题具有实际的借鉴作用。     

飞行员人体参数与人椅组合重心的回归分析研究

为确定火箭弹射座椅动力稳定调节方法设计所应依据的人体参数,对292例飞行员的人体参数及人椅系统组合重心数据进行了回归分析研究,综合确定了以体重和身高作为调节依据参数,并求出了该参数与人椅系统组合重心的回归方程。研究结果已用于火箭弹射座椅动力稳定调节方法的设计研究中。     

现场监测预警平台在高含硫气田应急救援中的应用

针对现行气田事故应急救援机制的不足,基于GIS技术构建了一个气田事故现场监测预警平台,通过无线传输实现应急救援指挥中心统一指挥、协同救援,提供全方位、可视化、高效的应急救援信息服务与决策支持,以提高应急救援的科学性和时效性。该平台能够在事故现场进行快速部署,对应急指挥进行辅助决策,并把现场音视频图像信息、有毒有害气体浓度信息、GPS信息、现场地形位置信息和现场风速、风向等信息实时发送到远端的指挥中心,为领导和专家提供现场资料,有利于及时决策、控制事故后果蔓延,维护社会稳定和人民财产安全。该平台除具备区域地理信息外,还包含有环境敏感区数据库、应急救援力量数据库和事故后果模拟模型库等,具有预测突发事件后果和在人机交互情况下模拟处理突发事故等功能。     

风载荷对舰载导弹出筒影响的仿真

针对舰载导弹垂直冷发射装置位于甲板之下容易忽略所受风载荷作用的问题,对风载荷对舰载导弹出筒 影响进行仿真研究。分析高海情条件下导弹出筒后所受风载荷作用特点,建立风载荷模型,根据导弹的出筒状态将 风载荷等效为变力矩和恒力的作用,用3 维建模软件Solidworks 构建发射模型,并导入到ADAMS 软件中进行模型 参数和约束条件的设定,聚焦导弹出筒的水平、弹射高度偏差以及姿态角3 个影响指标,对无风和有风情况下导弹 发射出筒进行仿真。仿真结果表明：风载荷对导弹出筒轨迹水平方向产生的位移影响较明显,对导弹姿态角和弹射 高度的影响较小。该研究对实际工作具有较好的指导作用。     

Regulator of G Protein Signalling 4 (RGS4) as a Novel Target for the Treatment of Sensorineural Hearing Loss

We and others have previously identified signalling pathways associated with the adenosine A₁ receptor (A₁R) as important regulators of cellular responses to injury in the cochlea. We have shown that the “post-exposure” treatment with adenosine A₁R agonists confers partial protection against acoustic trauma and other forms of sensorineural hearing loss (SNHL). The aim of this study was to determine if increasing A₁R responsiveness to endogenous adenosine would have the same otoprotective effect. This was achieved by pharmacological targeting of the Regulator of G protein Signalling 4 (RGS4). RGS proteins inhibit signal transduction pathways initiated by G protein-coupled receptors (GPCR) by enhancing GPCR deactivation and receptor desensitisation. A molecular complex between RGS4 and neurabin, an intracellular scaffolding protein expressed in neural and cochlear tissues, is the key negative regulator of A₁R activity in the brain. In this study, Wistar rats (6–8 weeks) were exposed to traumatic noise (110 dBSPL, 8–16 kHz) for 2 h and a small molecule RGS4 inhibitor CCG-4986 was delivered intratympanically in a Poloxamer-407 gel formulation for sustained drug release 24 or 48 h after noise exposure. Intratympanic administration of CCG-4986 48 h after noise exposure attenuated noise-induced permanent auditory threshold shifts by up to 19 dB, whilst the earlier drug administration (24 h) led to even better preservation of auditory thresholds (up to 32 dB). Significant improvement of auditory thresholds and suprathreshold responses was linked to improved survival of sensorineural tissues and afferent synapses in the cochlea. Our studies thus demonstrate that intratympanic administration of CCG-4986 can rescue cochlear injury and hearing loss induced by acoustic overexposure. This research represents a novel paradigm for the treatment of various forms of SNHL based on regulation of GPCR.     

核事故医学救援辐射监测工作的几点思考

辐射监测对于核事故医学救援至关重要。做好核事故医学救援辐射监测工作应重点掌握辐射防护相关知识,熟练掌握辐射监测设备的正确使用方法,并对辐射监测结果进行正确分析。本文通过分析辐射监测工作的重要性,就如何做好核事故医学救援辐射监测工作提出些许建议。