不稳定的

The transverse wave disturbance along tangential base flow of circular vortex is discussed By using numerical method we study this instability of baroclinic flow which is mesoscale inertia wave instability on the cylindrical coordinate The influence of stratification stability N 2 , Coriolis parameter f 0 , the vertical shear of tangential wind z of the ambinent atmosphere and the latent heat on the growth rate of instability is studied From the above analysis and calculation, we can learn that there are Eady mode and mesoscale mode of transverse wave instability in circular vortex as well Furthermore we also learn that distribution character of mesoscale mode disturbance field of transverse wave instability, anomalistic "cats eye" structure of lower level and the character of the slowly spreading disturbance converges at low level and the quickly spreading disturbance converges at high level

作者中文名：李红金；陆汉城；宋晓亮；李鲲摘要：讨论涡旋大气中，存在沿切向基流传播的横波型扰动，并采用数值方法讨论了柱坐标系下圆形涡旋系统斜压气流中这类扰动的不稳定，这是一类中尺度的重力惯性波的不稳定。研究了涡旋环境大气的层结稳定度参数N2、切向风垂直切变Vz、凝结潜热、涡旋特性及科里奥利参数f0对不稳定增长率的影响。圆形涡旋中同样存在横波不稳定的Eady模态和中尺度模态，得到了中尺度模态的扰动场分布特征：流场的不规则"猫眼"结构及慢速传播的扰动均集中在低层，而快速传播的扰动均集中在高层的扰动特征。

In chapter 3, we analyzed the motion near the collinear libration points in the model of circular restricted three body problem.

前者是稳定秤动点，对定位和轨控都比较有利，而后者是不稳定的，但可以是条件稳定的，其定位条件不同于L〓或L〓处。

The results show that the decalescence of catalyst bed affects the process of hydrogen peroxide catalytic decomposition greatly. If the catalyst bed is preheated or made up of materials with low thermal conductivity, that influence can be depressed. At the same time, the response characteristic of catalyst bed and the efficiency of catalytic decomposition can be improved. The low frequency pressure instability of catalyst bed occurs because of the coupling of catalytic decomposition and supplying. The decomposition plane pushes all the way through the catalyst bed during pressure oscillations, causing unreacted liquid hydrogen peroxide to be exhausted from the bed and leading to the appearance of liquid hydrogen peroxide channeling. Consequently, how to prevent or at least limit this channeling is the key to eliminate the pressure instability of catalyst bed. It was found that adding clapboard to the catalyst bed can depress the pressure instability efficiently.

结果表明催化剂床及催化剂的吸热对过氧化氢分解过程影响很大，对催化剂床进行预热或采用热导率低的材料制造催化剂床等措施，可以降低催化剂床壁面吸热对催化分解过程的影响，提高催化剂床的响应特性和催化分解效率；催化剂床的低频不稳定是催化分解过程与供应系统耦合产生的，催化剂床气体界面的波动过程中，液体过氧化氢穿透催化剂床形成过氧化氢液体通道，过氧化氢液体通道的产生和扩大是催化剂床不稳定的主要原因，也是消除催化剂床不稳定的关键，试验中在催化剂床内加入分流板成功地抑制了催化剂床的低频不稳定。

Only if these instable elements arrive at some level, the political instability will be changed into reality.

当然，生成和存在不稳定因素只是表明这里存在不稳定的可能性，只有当这些不稳定的因素达到一定的度，才会酿成现实的政治不稳定。

BPH is a common disease in old people, it often causes bladder outlet obstruction and destrusor instability. It is reported that the morbidity, rate of detrusor instability secondary to BPH is from 52% to 80%. There are many hypotheses concerning detrusor instability, The study of detrusor denervational hypersensitivity and changes of detrusor ultra-structure are intensively popular at present. But most of the research work were only limited in animals. In order to gain the insight into its mechanism, we Carried out a series of studies on detrusor instability secondary to BPH obstruction in men.

BPH是老年人常见疾病，常导致膀胱出口梗阻和逼尿肌不稳定，有报道BPH梗阻性逼尿肌不稳定的发生率为52-80％，引起逼尿肌不稳定原因很多，其中逼尿肌去神经超敏和超微结构的变化是目前研究的热点，但大多限于动物实验，鉴于此，我们对BPH梗阻性逼尿肌不稳定进行了初步的研究，拟探讨其发生机制。

Stable and Unstable Orbit: An orbit is unstable if slight perturbations will cause the spacecraft moving on the orbit to leave the orbit and move far away.

稳定和不稳定轨道：不稳定的轨道上，如果稍有扰动将导致飞船在轨移动到离开轨道和移动远。

In the course of alteration,the unstable elements in supergene zone are leached out in quantity,but the stable ones are relatively enriched.

在蚀变过程中，那些在表生条件下不稳定或较不稳定的元素大量流失，而那些稳定或较稳定元素则很少流失或相对富集。

Resultantly, the individual warm/cold events in ENSO cycle appear to be partially locked to the annual cycle, and also exhibit obvious irregularity both in amplitude and in lasting time.

本文第四章研制设计了一包含海洋表面边界层和大气辐合反馈过程的热带太平洋海气耦合异常模式，进而利用该模式对ENSO循环进行了较为真实的模拟，通过对模式ENSO循环的演变特征及其形成机制的细致分析，建立了-ENSO循环的非线性分析模式，并提出了ENSO循环形成的一种更为客观的理论，指出：1）和观测事实类似，模式ENSO循环确实涉及了三种主要时间尺度过程即LF、QB和AC，其中LF为3-4年主周期振荡，QB占总方差10～20%；2）ENSO循环的正反馈机制是不稳定海气相互作用过程，且这一不稳定过程的发展在暖态中明显强于冷态；3）ENSO循环的负反馈机制在冷暖态中表现不同，在冷态消亡过程中，这种负反馈过程主要表现为西边界反射产生的时滞效应，但在暖态消亡过程中不存在类似的时滞效应，其负反馈过程主要表现为在海气耦合不稳定充分发展时伴随的赤道两侧冷水上翻过程的加强以及非线性过程的衰减作用抑制了不稳定的发展并最终使得系统回复至冷态；4）ENSO循环的3-4年主周期振荡是一非线性系统的自激振荡现象，其形成是线性系统的本征模即准两年振荡通过非线性机制产生的周期加倍所致，其中&单向性&大气辐合反馈加热过程对其形成至关重要；5）虽然年循环过程对ENSO循环形成没有本质影响，但它可明显影响ENSO循环的具体振幅和位相，使得ENSO对季节循环有明显的&锁相&特征，并且也使得ENSO循环在振幅大小和时间长短方面呈现出明显的不规则性。

Evidence suggests that 1 under more stable stratification, the basic flow, if moving faster at low and high levels (particularly in the presence of jets there), allows a resulting meso-β unsteady wave to propagate eastward with respect to basic flow and even at greater velocity compared with it; 2 vertical windspeed shear of basic flow causes instabilities of the TWT perturbation; 3 considering the second derivative of basic-flow wind with respect to z (denoted by zz≠ 0 which is simply given as β* hereafter) the expression for the phase velocity of vortex Rossby wave is obtained, which is unidirectional in propagation with respect to basic flow; 4 VRoW has its physical origin from β*, i.e., from z-varying heterogeneities of y-direction averaged vorticity of the basic flow field; 5 VRoW phase velocity is associated with zonal wave number k, its energy is dispersive and the group velocity exists in the x direction; 6 when windspeed meets the condition of β*, TWT disturbance instability may be that of mixed VRoW and gravity wave; 7 if basic flow is subject to linear shear but does not meet the condition of β*, the TWT instability is that of inertia-gravity wave.

在大气层结比较稳定的情况下，如果基本气流在低层和高层较大(有可能存在低空急流和高空急流)，此时产生的β中尺度不稳定扰动相对于基流向东传播，甚至于快速向东传播。基本气流在垂直方向上的风速切变对于中尺度横波型的扰动起着不稳定的作用。如果考虑基流的二次切变，可以得到涡旋Rossby波的相速度表达式，涡旋Rossby波相对于基本气流是单向传播的。涡旋Rossby波产生的物理根源是基本流场的风速二次切变，亦即基本流场y方向的平均涡度在空间z方向上的不均匀所致。涡旋Rossby波的相速度与纬向波数也有关，它的能量是频散的，其在纬向x方向也存在群速度。在基本流场的风速存在二次切变时，横波型不稳定可能是混合的涡旋Rossby重力波的不稳定；而在基本流场的风速仅仅存在线性切变，不存在二次切变时，横波型扰动的不稳定则是重力惯性波的不稳定。

AFTER days of leaks and rumours that destabilised不稳定的 stockmarkets, Gordon Brown's Labour government unveiled a comprehensive广泛的,综合的 rescue package for Britain's ailing不舒服的,生病的 banks before markets opened on Wednesday ctober 8th.

证券交易情况不稳定的传言泄露了几天后，在10月8日星期三开市前，Gordon Brown的工党政府公布了一个为英国陷入危机的银行制定的救市法案。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷