基于自适应方法的Sn／O／H／N／C／Cl反应机理简化

计算包含详细反应机理的复杂反应流问题仍然是十分费时的,已有的反应流计算方法通常采用简化的化学反应机理.传统的机理简化方法大多基于反应条件的稳态假设,如主量组分分析法等.近年来,一种基于自适应化学理论的机理简化的新方法被提出.该方法根据设定的化学精度要求,可实现详细反应机理的最优简化.对Sn/O/H/N/C/Cl详细反应机理的简化结果表明Sn CO2=SnO CO和Sn O2=SnO O为机理中影响Sn氧化最重要的两个基元反应.     

用于彩色目标跟踪的改进粒子群优化算法

提出一种用于彩色目标跟踪的改进粒子群优化算法(Improved Particle Swarm Optimization Algorithms,IP-SOA)。针对彩色目标,选择加权彩色直方图作为目标的特征,选用Bhattacharyya系数作为特征相似性度量,其最大值位置表示目标位置。对粒子群优化算法进行了改进,即自动调整惯性权重函数与认知学习因子,每次递推时对粒子速度、单帧位移总量加以限制,对Bhattacharyya系数优化,快速求取函数最大值位置。利用彩色序列图像进行仿真实验,结果表明,该方法能够实时跟踪飞机、车辆等目标,在目标被部分遮挡时能稳健跟踪。     

高功率毫米波辐照鼠疼痛阈值及应激反应

 高功率8 mm波辐照时，大小鼠均产生热应激反应，依次经历平静期、警戒期、相持期和衰竭期。鼠的热痛阈值温度为(43.1±1.8) ℃，这一阈值与鼠的质量、初始温度、辐照功率密度等无关。 辐照3 s时：辐照功率密度为3.5 W/cm2时体表温升为(8.4±1.0) ℃；辐照功率密度为7.0 W/cm2时温升为(21.1±3.0) ℃。实验还测定了警戒期持续时间，结果表明动物应激反应的剧烈程度与警戒期持续时间相关。建立了小鼠警戒期持续时间与小鼠体表面积、有效辐照面积、辐照功率密度之间的关系，并将这一实验结果推广到大鼠。     

大范围光纤Bragg光栅压力传感器增敏实验研究

鉴于钛合金材料具有低弹性模量、受温度影响小等特性,设计制作了一种以钛合金管作为光纤Bragg光栅应变增敏衬底元件的高压压力传感器件.通过与电阻应变计实时监控的对比,从实验上研究了光纤Bragg光栅的中心波长偏移对调谐压强的响应.结果表明:这种增敏设计,具有良好的线性响应和可重复性,且与理论推导结果吻合较好.增敏后对压力的响应灵敏度可达0.034 nm/MPa,测压量程可达0~40 MPa,甚至更宽.     

高温下正十五烷的拉曼光谱研究

文章在金刚石压腔下研究了正十五烷从室温到350℃的拉曼光谱特征.结果表明:随着温度的升高,体系压力也在不断增大;CH3,CH2对称和反对称伸缩振动同时受到温度和压力的影响,但2种作用相反.由于压力效应大于温度效应,随温度压力的增大CH3,CH2对称和反对称伸缩振动的拉曼位移均向高频方向移动,说明C-H键键能在增大.另外,由于新物质的生成导致过强荧光产生而无法测出正十五烷的拉曼光谱,而且过强荧光出现的时间早晚与温度和压力有一定的关系.     

Strongly Correlated Effect in TiS2

The thermoelectric compound TiS2 is studied by using the full-potential linearized augmented plane-wave method on the density functional theory with the generalized gradient approximation （GGA） as well as the on-site Coulomb interaction correction （＋U）. The Seebeck coefficient of TiS2 is calculated based on the electronic structure obtained within the GGA under the consideration of the on-site Coulomb interaction. The calculated Seebeck coefficient at 300K shows that Coulomb interaction U in the range of 4.97-5.42eV is important to reproduce the experimental data. The obtained energy gap Eg around 0.05 eV indicates that TiS2 is an indirect narrow-gap semiconductor.     

大孔径静态干涉成像光谱仪的信噪比分析

根据大孔径静态干涉成像光谱仪的原理和特点，分析了光辐射能在光学系统内的传输情况，对探测器上接收到的光辐射能信号和噪音信号做了详细的推导，得到了仪器理论信噪比的表达式.在实验上以大口径积分球为辐射源，采集仪器输出的干涉图像，计算得到仪器的实际信噪比曲线，对大孔径静态干涉成像光谱仪的理论信噪比曲线与实际的信噪比曲线做分析比较，结果验证了用推导的论信噪比的表达式来预估仪器信噪比的可行性.     

Synthesis and shape memory behavior study of hyperbranched poly(urethane-tetrazole)

A novel hyperbranched poly(urethane-tetrazole)(HPUTZ) was synthesized via the A2+BB2' approach using hexadiisocyanate(HDI) and 3-(bis-(2-hydroxyethyl)) aminopropyltetrazole(HAPTZ).The molecular structure was characterized by FTIR and 1H NMR spectroscopy.The number average molecular weight was measured to be 1.05×104 g/mol with a polydispersity of 1.27 by GPC analysis.The HPUTZ was further cured by the semi-adduct(PEG-IPDI) from polyethylene glycol(PEG) reacting with isophorone diisocyanate(IPDI) to form th...     

Experimental study on turbulent mixing of spray droplets in crossflow

Centrifugal spray injected at various angles in gas crossflow has been studied experimentally using PIV visualization system and image-processing techniques. Experiments were carried out inside a rectangular duct (95 mm × 95 mm in cross-section) at ambient temperature and pressure, with different gas Reynolds numbers (vary from 12,900 to 45,000) and three injection angles (60°, 90° and 120°). The spray angle of the centrifugal nozzle is 80°, with D₃₂ of 80 μm. The instantaneous images of droplets distribution and the values of the line-averaged D₃₂ at different positions on the cross-sections along the flow field for each condition were obtained, and their flow field configurations were achieved. Quantitative assessments of mixing degree between two phases for different injection angles were determined using a spatial unmixedness parameter. It is found that the addition of droplets into the gas crossflow enhanced the turbulence intensity of the gas crossflow and caused different-scale vortices. The flow field structure, to a great extent, is dependent on the injection angle. The entrainment and centrifugal force of large vortex lead to uneven droplet distribution and moreover influence the mixing of droplets and gas crossflow. A better mixing result can be obtained with the injection angle of nozzles of 60°.     

苯在[K.Ti]ZSM-5上由H2O2氧化制苯酚的研究

由 HZSM-5与 K2 Ti F6 水热法同晶取代制备 [K.Ti]/ ZSM-5 ,并用 XRD、SEM、IR给予表征 ,其在等摩尔的苯、苯酚、H2 O2 液相反应体系中 ,常温下表现出较高催化活性 ,苯转化率达 83 % (1 6h) ,选择性≥ 98% ,苯酚产率为 2 .4m M/ h· Cat(g) ,同时探讨了有关影响因素。