相变

The calculation and experiment results show that the maximum lifting pressure performance decreases with the increase in throat diameter of channel of variable section, water flux of low pressure and pressure ratio of steam nozzle, and has its minimum value with water nozzle annular space. The coefficient of maximum lifting pressure performance may be as high as 26. In the design of steam injector, the larger pressure ratio of steam nozzle and the smaller water nozzle annular space are selected, the higher lifting pressure performance could be obtained.

计算及研究表明：极限升压能力随变截面混合腔喉部直径、被升压的低压水流量和蒸汽喷嘴压比增加而降低，随环形水喷嘴间隙的变化出现了最小值；计算得出变截面超音速汽液两相流装置的极限升压能力可达26；在设计升压装置时应尽可能选取较大的蒸汽喷嘴压比和较小的环形水喷嘴间隙。

The retrogradation kinetics properties of starch paste could be described well by rheological index.

当引入连续相流变指数和分散相沉淀率变量时，老化动力学模型的拟和精度进一步提高。

The results show that:(1) The space-charge fields(include dc space-charge fields and ac space-charge fields) have important effect on the beam-wave interaction output power, make the saturated output power lower, saturated position delay;(2) The back-radio excited by the electron beam has little effect on the output power, and can be ignored;(3) The transverse motions of electron beam has some effect of the output power;(4) The means of phase velocity taped and bunch compression can improve the relativistic TWT efficiency, especially bunch compression can greatly improve the efficiency.

五、分析了相对论行波管三维非线性特性，分析结果表明：(1)空间电荷场（包含直流和交流空间电荷场）对注波互作用输出功率影响很大，会造成饱和输出功率减小，饱和位置推后；(2)电子注激发的反向辐射对输出功率影响比较小，基本上可以忽略不计；(3)电子注横向运行对注波互作用的直接影响比较大；(4)通过改变耦合腔内半径来调节慢波结构相速，采用相速跳变和预群聚的方法可以改善相对论行波管的效率，特别是采用预群聚方法，可以尽量提高相对论行波管的效率。

Othermore, 29 kinds of 3rd-7th order depositional cycle that could be divided into asymmetric upshallowing、 up-deepening and symmetric cycles are obtained from shallow-sea facies Devonian.

此外，通过对相组合、剖面结构纵向上相序变化的研究，浅海相区泥盆系的沉积旋回样式大致可区分不同级别的29种，概括起来包括非对称性向上变浅、加深和对称性三类。

A new kind of frequency-converting timing system of short phase-shifting current mode circuit was introduced in view of the defects of inverse circuit of series-wound diode current mode,which is widely adopted in frequency-converting timing systems.

针对应用较为广泛的串联二极管式电流型逆变电路变频调速系统存在的缺点，提出了一种新型的短路换相式电流型逆变电路。

The control signals of the PWM rectifier are obtained by comparing the current of AC side with triangular wave (or saw-tooth wave) directly, which can implement the steadiness of the voltage of DC side and unit capacity factor of the system. At the same time, harmonic component of the system is abstracted through Instant Reactive Power Method, which can be smoothed by Integrated Learning Boost Converter Control.

本文采用重复学习Boost变换技术，利用滑模变结构控制技术对单相PWM整流器恒频Boost变换进行了分析，提出将交流侧电流直接与三角波相比较得到开关控制信号的方法，实现直流电压恒定不变及系统单位功率因数；同时，利用瞬时无功功率法分析系统谐波，并在谐波域内使用重复学习的控制方法，结合Boost变换技术，有效滤除系统谐波有功电流。

Therefore, the observation of Na layer is one of the important method to study the dynamical process in the mesopause region. In this paper, we combine a timedependent photochemical model, the International Reference Ionosphere model (IRI95) and a photochemical model of sodium to develop a time dependent sodium photochemical model.

本文建立了时变的中高层大气光化学模式，并与国际电离层模式(IRI95)与Na层光化学理论相结合，建立完整时变的中高层大气Na层光化学模式，着重研究Na层分布的昼夜变化。

Digital simulation is an important step for torpedo turbine engine design. This paper investigates the modeling and simulation of unclosed cycle and partial flow two-stage impulse torpedo turbine in design condition and two non-design conditions. The control modes of turbine in non-design conditions are discussed.

进行鱼雷涡轮动力装置数字仿真是设计涡轮机的重要步骤，为此，该文针对鱼雷涡轮机设计和研制的需求，采用理论分析、经验推导和实验研究相结合的方法建立了鱼雷开式循环部分进气纯冲动式复速级涡轮发动机设计工况及2 种常见变工况的数学模型，着重讨论了变工况过程涡轮机的调节控制方案，提出了简便易行的开关喷嘴控制方法，并对其进行了数字仿真研究。

Firstly, the control of reentry phase and the model of RCS jets are presented. Then the flight control system is divided into two subsystems based on the time-scale separation principle. The fast states subsystem corresponds to the three body-axis angular rates, the slow states subsystem controls the angle-of-attack, sideslip angle and the rate of the bank angle about the velocity vector. Lastly, the proportional-plus-integral feedback is designed to increase the system robustness.

首先，分析了SRLV再入段的数学模型，并给出了反作用推力控制系统的控制模型；其次，将非线性动态逆方法与时标分离原则相结合，考虑飞行器姿态控制系统的外环角回路的慢变特性和内环角速度回路的快变特性，独立设计了两个回路的控制律；最后，为了增强系统的鲁棒性，分别在两个回路中引入了比例－积分反馈，有效地抑制了干扰力、力矩和非线性对消带来的逆误差。

FRs can strongly suppress the elimination of HCl, raise the on-set temperature of decomposition of PVC, promote the crosslinking during decomposition, reduce the total output of aromatic compounds, increase the gel of condensed phase and char residue, the char residue is loosened. The configuration of FRs has no changed.

这类阻燃抑烟剂能抑制PVC热分解脱HCl反应，提高HCl释放的起始温度，在热分解过程中促进分子间形成交联键，使裂解气相产物中芳烃化合物含量减少，凝聚相凝胶含量增大，残炭量提高，残炭物结构呈松散状态，阻燃抑烟剂在热分解过程中化学结构保持不变。

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。