细水雾与火焰相互作用的热成像全场动态测量

利用ＴＶＳ－２０００ＳＴ热像系统对细水雾与火焰相互作用过程中的动态热场进行了测试,获取了细水雾作用前后火焰热场信息变化的时空分布,从而为进一步深化认识细水雾与火焰相互作用的机理提供了简捷可靠的实验手段。同时,对在不同水压下细水雾与火焰相互作用的全过程进行了动态测试。     

细水雾与火焰相互作用的红外全场诊断方法研究

利用ＴＶＳ－２０００ＳＴ型热像系统,通过观察和测量细水雾与火焰相互作用前后火焰热场结构的变化,分别对细火雾与煤油、酒精和正庚烷等液体扩散火焰的相互作用进行了实验研究,为进一步认识细水雾与扩散火焰相互作用的机理提供了简捷可靠的实验手段     

用红外热成像方法研究纸板表面火蔓延特性

应用红外热成像方法实验研究了在一定风速情况下(顺风／逆风)典型的可燃固体材料硬纸板上下表面都处于流场中的情况，表面火蔓延的特性；并与施加超细水雾后火焰的蔓延状态对比，探究了细水雾对固体燃料火焰的抑制作用，为矿井中传送带类型的火灾的处理方法等工程应用定性地给出了一种实验依据。     

红外热成像方法测量火旋风温度的实验研究

应用热成像方法获得了火旋风特有的物理现象，火焰的大高度直径比；并将细水雾作用于火旋风和油池火实验；相同的雾通量作用下，火旋风能被熄灭，油池火却不能被灭掉。由此而对细水雾作用于火旋风的机理进行了讨论，对于不同物理形态的火焰，细水雾灭火的有效性不同。并对细水雾抑制熄灭火旋风火灾机理的研究提出了一种有效的实验方法。     

细水雾抑制气体火焰的实验测量

运用APV(Adaptive Phase／Doppler Velocimeter)系统、红外热成像方法和热电偶测温方法对细水雾和气体扩散火焰的作用过程中雾通量等雾场特性做了有效的测量，研究了细水雾和气体扩散火焰的作用过程。探索细水雾抑制扩散火焰的机理和规律。采用一种可以分离出细水雾灭火时不同机理相对贡献的实验方法，得到了比较理想的结论，用实验数据形象定量的表征出了在细水雾灭火时，水雾的蒸发潜热吸热作用、热容吸热作用以及稀释氧气作用对抑制气体扩散火焰所起的相对贡献。在实验条件下，讨论了细水雾各种灭火机理，合理解释了实验中出现的一些现象。实验研究表明，细水雾的各种灭火机理对于抑制火焰所发挥的作用不同，这对于细水雾灭火技术的发展很有意义。     

利用锥型量热计研究细水雾作用下的油池火热释放速率

热释放速率是燃烧过程最基本的特性参数之一，在研究细水雾与油池火相互作用时可以用来表示其动态发展过程．基于燃烧耗氧原理，锥型量热计被广泛利用来测量热释放速率，其测量条件之一是进入测量系统的气体仅来自于环境空气．当利用锥型量热计来研究细水雾与油池火相互作用时，部分细水雾会受热气化并改变进入锥型量热计中气体浓度，从而导致一定的热释放速率测量误差．本文提出了一种简单的方法来修正相应的热释放速率数据，并在此基础上利用锥型量热计研究了细水雾作用下的油池火热释放速率特性．实验中着重考虑了油池尺度、燃料特性、细水雾雾通量等因素的作用． 研究结果表明，在足够雾通量的细水雾作用下，热释放速率明显降低，然而在少量细水雾作用下，热释放速率会有所啬增加，对于一些不能完全燃烧的燃料试样，后者更加明显．     

细水雾与射流卷吸现象的LDV/APV测量研究

本文利用三维激光多普勒测 计和自适性相位移普勒速度计系统（三维ＬＤＶ／ＡＰＶ系统）,通过观察和测量细水雾被射郑吸的现象,获取了细水雾的平均速度,平均粒径和雾能量等特性参数,深化认识细水雾被射流卷吸的机理,为下一步进行细水雾被火焰卷吸现象的实验研究打下了良好的基础。     

三维LDV/APV系统研究细水雾与射流卷吸现象

利用三维激光多普勒测速计和自适性相位多普勒速度计系统（三维ＬＤＶ／ＡＰＶ系统）,通过观察和测量劝水雾被射流卷吸的现象,获取了细水雾的平均速度、平均粒径和雾通量等特性参数,深化认识细水雾被射流卷吸的机理,为下一步进行细水雾被火焰卷吸现象的实验研究打下了良好的基础。     

激光与固体透明介质相互作用的力学效应

本文从球体模型出发,研究了激光与固体透明介质相互作用的热弹性应力波激励机理,并进行了实验验证,得到了环氧树脂内部变化的光致热弹性应力波传播速度。     

三向侧面泵浦固体激光器中热透镜的研究

本文理论分析侧面泵浦固体激光器热透镜效应，详细讨论介质中泵浦光分布和温度梯度分布，提供了热透镜的数值解法。实验研究三向侧面泵浦固体激光器的热透镜，所测实验结果与数值计算结果相吻合。该数值方法为DPL的谐振腔设计提供有效途径。     

High‐Efficiency Low‐Resistance Oil‐Mist Coalescence Filtration Using Fibrous Filters with Thickness‐Direction Asymmetric Wettability

Conventional aerosol filters typically have homogeneous wettability with limited filtration ability especially for small oil mists. Increasing filtration efficiency using thicker filter pad or finer fibers both result in considerable increase of pressure drop, which adversely increases energy consumption. It remains a challenge to develop effective filter materials that can effectively remove oil mists from air at a low flow resistance. Here, a novel concept about improving oil mist filtration efficiency without apparently increasing pressure drop using a fibrous filter with asymmetric wettability across the thickness is demonstrated. Dip‐coating and single‐side electrospraying are used to make fibrous filter have a homogeneous superoleophobicity or directional oil‐transport function. When the two are combined together, they show a filtration efficiency as high as 99.45% for small oil mists (size 0.01–0.8 µm) and nearly 100% for large oil mists (size 0.5–20 µm) with a pressure drop of 9.29 kPa. With the same thickness and fibrous structure, our directional oil‐transport/superoleophobic filter has higher quality factor than those with homogeneous oleophilic, superoleophobic, and asymmetric wettability of other superoleophilic/superoleophobic combinations, for both small and large oil mists. Directional oil transport‐superoleophobic filters may lead to a novel, high‐performance, low energy consumption oil mist separation technology.     

Diffusion of moisture through optical fiber coatings

The strength of polymer-coated fused silica optical fiber is dependent on the ambient moisture because of stress corrosion. The diffusion rate of water vapor through the polymer coating can be estimated by monitoring the strength as a function of time after suddenly changing the ambient humidity. Not only is this technique a new way of sensing humidity, but it also allows estimation of the time needed for the coated fiber to equilibrate with its environment. A comparison has been made between the diffusion coefficients measured in this way and by monitoring the weight of free-standing polymer films as a function of time. Fickian diffusion has been assumed and is justified by the good agreement between the experiment and theory. The diffusion of water vapor both into and out of various polymers was investigated     

斜坡非饱和带低渗透岩石中水气分子的扩散机理

根据分子运动论,对水气分子在低渗透岩石中的扩散模式进行研究,得出水气分子中的主要气体H2O、CO2以及O2在新鲜二长岩和玄武岩中的扩散为过渡型扩散.通过计算得到三者的有效扩散系数.以微砂质细粒长石石英砂岩为研究对象,在电子显微镜下获得砂岩的铸体薄片图像,并对其进行处理,建立砂岩的二维孔隙扩散模型,模拟岩石风化过程中水气分子在砂岩孔隙内的扩散过程,得到砂岩模型内部的速度分布图、压力分布图和雷诺数图.结果表明,天然状态下,水气分子的流动主要出现在胶结物受腐蚀的风化区域.胶结物溶蚀产生的贯通孔隙是水气分子的主要扩散通道和贮存场所.水气分子在砂岩内部孔隙中的流动符合流体流动的基本规律,雷诺数的量级为10-3,流动状态为层流.同时对风化岩石的剖面进行分带,分析了水气分子扩散对岩石风化产生的影响.     

Transport of moisture at epoxy–SiO2 interfaces investigated by molecular modeling

In this work, the transport of water molecules at the interface of an epoxy molding compound to a SiO₂ (chip surface) is investigated by molecular modelling. Experi-mental results of bulk diffusion of H₂O into a DGGOA/DAIIBA epoxy/hardener system at several temperatures are compared to molecular dynamics results at elevated (artificial) temperatures with respect to activation energies. Molecular modelling allows to trace individual molecules over time. The recorded traces are evaluated in a semi-quantitative way with respect to jump-distances and comparisons are made between bulk diffusion, diffusion at an interface and diffusion at open surfaces of the involved materials. Results show reasonably agreeing activation energies in experiment and simulation and an enhanced transport at open surfaces. A significantly enhanced transport at a perfect interface could not be confirmed in this investigation.     

Study of Electron Heat Pulse Propagation and Particle Diffusion During the Synergy of LHW and IBW Heating in the HT-7

A successful experiment on lower hybrid wave (LHW) and ion Bernstein wave (IBW) synergy has been carried out in the HT-7 superconducting tokamak. With 560KW of LHW heating power and 160 KW of IBW heating power, during the synergy of the LHW and IBW experiment we achieved an improved plasma: the electron density increased and peaked, the soft X intensity increased too. A five-channel far-infrared (FIR) hydrogen cyanide (HCN) laser interferometer was used to measure the electron density profile. The particle diffusion coefficient was studied for the experiment, and the result compared with the heat diffusion coefficient. With the same injected LHW and IBW power, high electron density n_e can deduce the electron pulse propagation and the particle diffusion.     

InGaAs/InP材料的Zn扩散技术

使用MOCVD反应室进行了InGaAs和InP材料上的Zn扩散工艺条件研究.通过控制扩散温度、扩散源浓度和扩散时间三个主要工艺参数,研究了InGaAs/InP材料的扩散系数和扩散规律,获得了优化的扩散条件.试验表明,该扩散工艺符合原子扩散规律,扩散现象可以用填隙-替位模型解释.样品经过快速退火过程,获得了极高的空穴浓度.InP的空穴浓度达到7.7×1018/cm3,而InGaAs材料达到7×1019/cm3.在优化的扩散条件下,Zn扩散的深度和浓度精确可控,材料的均匀性好,工艺重复性好,能够应用于光电探测器或其他器件.     

Analysis of the effect of sodium on the physical properties of an oxide-coated cathode

A method for computer simulation of atomic sodium adsorption, desorption, and diffusion in an oxide-coated cathode is proposed. The problems are solved with TURBO PASCAL codes. The results of the in situ experiment are compared with the results of the computer simulation. The comparison confirms the vacancy mechanism of the diffusion.     

火灾早期过程特征的红外光谱探测和诊断

提出用CO作为早期火灾探测的观察对象,利用红外光谱法进行气体探测,并在此基础上建立了基于FTIR的试验系统.通过该方法成功获得CO的浓度值.并用时间序列分析方法建立二阶自回归模型,提取出特征参数进行分析,能在较短时间内将真假火灾区分开来.