连续陶瓷纤维的制备、结构、性能和应用:研究现状及发展方向

连续陶瓷纤维是纤维增强陶瓷基复合材料的增强体,对提高陶瓷基复合材料的强度和韧性起关键作用,高损伤容限和高强度陶瓷纤维是阻止裂纹扩展实现陶瓷基复合材料强韧化的保障。本文对碳化硅、氮化硅、氮化硼、氧化铝和氧化锆等几种陶瓷纤维的制备方法、结构、性能和应用等方面进行了全面的综述,指出了今后的发展方向,期望为未来陶瓷纤维的研究、开发及应用提供参考。国家高技术研究发展计划(863)(2003AA305630);;国家自然科学基金(51472144);;山东省科技重大专项(2015ZDZX11003);;山东省青年学者未来计划(2016WLJH27

Review of rTMS on treatment of smoking behavior

烟草危害是当今世界最严重的公共卫生问题之一。吸烟与恶性肿瘤、心血管疾病等多种疾病相关,且戒除困难。rTMS是一种无创神经调控技术,具有治疗吸烟的潜在价值。我们检索了Pubmed、Cochrane databases和万方数据库,最终纳入14个符合入组标准的临床研究,分析rTMS治疗吸烟的临床疗效及其可能机制,发现左侧前额叶背外侧皮质(DLPFC)高频(10 Hz)rTMS对治疗吸烟有临床疗效,并推测这一效应可能与高频rTMS影响大脑奖赏环路功能活动相关。然而,现存研究存在诸多不足,不能为rTMS治疗吸烟提供充分的科学依据,该领域的进一步深入研究对于吸烟治疗有重要意义

Effect of the fuel-air flow velocity on heat release rate of swirling non-premixed methane flames

A laboratory-scale gas turbine model combustor fueled with methane is studied experimentally with the aid of three-dimensional computed tomography of chemiluminescence (3D-CTC) and high speed (5 kHz) chemiluminescence imaging. Various fuel-lean operating conditions were tested to investigate the impact of flow velocity on heat release rate oscillation and spatial structure transition with fixed global equivalence ratio of about 0.65 and dump plane velocity of 2.9-18.3 m/s. In the study of combustion structure transition, the three-dimensional relative emissions of CH* were measured and taken as qualitative indicators of the heat release rate. This 3D measurement method utilizes CH* images from 8 directional as inputs combined with tomographic algorithms to compute the 3D distribution of CH* CL intensities. For all tested conditions, pronounced extension of inner recirculation zone (IRZ) along the nozzle is observed under the attached (V-shaped) swirl stabilized flames. During the increase of Reynolds number, the heat release zone changing obviously along the nozzle radial and axis direction, and the largest heat release plane moves downstream significantly. In addition, an intensified high-speed camera was adopted for the heat release dynamics study. Strong oscillations appeared in the flame zone that significantly affected the total heat release oscillations, and oscillation increases with the raise of Reynolds number. (C) 2019 Elsevier Masson SAS. All rights reserved

Determination of organophosphorus and carbamate insecticide residues in food and water samples by solid phase extraction coupled with capillary liquid chromatography

A method was established for the simultaneous separation and determination of one organophosphorus and three carbamate insecticide residues in food and water samples by solid phase extraction (SPE) followed by analysis using a home-made capillary liquid chromatogram. Various parameters possibly affecting the efficiencies of capillary liquid chromatography (CLC) and SPE were investigated in detail, such as type of SPE column, pH value of samples, type and volume of elution solvent, flow rate of loading sample, salt effect, loading volume, detection wavelength, and type and ratio of mobile phases. Under the optimized experimental conditions, the four insecticides were separated completely within 6 min. The limits of detection and limits of quantification were 0.35-1.20 μg/kg and 1.17-4.00 μg/kg, respectively. Satisfactory recoveries of the SPE-CLC method were achieved for spiked food samples of tomato, cucumber and apple ranging from 72.41% to 107.15% with the relative standard deviations (RSDs) no more than 8.12%, and for spiked tap/lake water samples ranging from 71.45% to 109.25% with the RSDs no more than 9.28%. The method can meet the requirements for multi-residue analysis of insecticides

乌鲁木齐环境容载力与城市污染控制对策

三年时间课题组进行了大量的调查、典型监测、取样分析,从乌鲁木齐环境保护和经济建设要求的生态环境研究入手,以指导乌鲁木齐区域环境保护和生态建设实践为落脚点,以市政府决策部门为用户,结合生态学、环境学、地理学、地质学、气象学、水文学、生物学等,建立了环境容载力研究的理论方法框架、提出了环境容载力评价的指标体系和计算的模型方法、设计了环境容载力的判据模型和环境生态位的计算模型、确定了乌鲁木齐环境容载力总量及其控制目标的生态位、提出了乌鲁木齐市可持续发展城市战略模式

空间辐射生物学研究进展；Research Progress on Space Radiation Biology

空间电离辐射尤其是高能带电粒子辐射可造成生物机体的严重损伤,是载人航天飞行的关键性限制因素之一。研究表明,带电粒子的生物学效应与其性质、剂量以及不同生物学终点有关;此外,微重力环境可能会影响空间辐射生物学效应。从多年来的空间搭载实验研究和地基模拟实验研究两个方面,综述了空间辐射的生物损伤效应及其与微重力环境复合作用的生物效应

X射线辐照后人肝细胞、肝癌细胞存活与端粒酶活性关系的研究

利用X射线对体外培养的人肝癌细胞SMMC-7721和正常人肝细胞HL-7702进行辐照,以细胞克隆形成法测定细胞存活率,多聚酶链式反应银染端粒重复序列扩增法(Telomeric repeat amplification protocol,TRAP-PCR)检测细胞中端粒酶活性变化,探讨辐照后细胞存活与细胞中端粒酶活性变化的关系。结果表明,SMMC-7721和HL-7702细胞的存活率都随辐照剂量的增加而相应降低。在1-4Gy剂量范围内,两种细胞的端粒酶活性变化均呈剂量依赖性增强。但在1Gy、2Gy、3Gy剂量下,SMMC-7721其端粒酶活性较对照(0Gy)细胞低;当辐照剂量达4Gy时,端粒酶活性略高于对照细胞。在1-4Gy剂量范围内,HL-7702和SMMC-7721的细胞存活与端粒酶活性在变化趋势上呈负的关系