小的环

By using the sliding mode approach and a multi-step control strategy, a new controller is presented, which can not only satisfy the control constraints but also stabilize the system to an arbitrarily small ε-neighborhood about its equilibrium in a finite time.

利用滑动模态的思想和多步控制策略，设计了不连续反馈镇定律，该镇定律一方面满足控制受限条件，另一方面使得闭环系统的状态收敛到预先给定的原点的任意小的ε邻域中。

For the integrable Hamilton systems, the Invariant tori can be continuation in a certain range if the perturbation of the coupled systems is small enough.

对可积分的Hamilton系统，加上足够小的扰动，系统的不变环面所代表的规则运动在一定范围内都是可延拓的。

They have a smaller and stronger frame, knobby, as well as wider and higher-profile tires, which are mounted on a rim that is stronger and more durable than a standard bicycle rim.

他们有一个更小的和更有力的框架， knobby ，以及更广泛和更高的知名度轮胎，这是安装在轮辋是更强大和更持久的比标准的自行车环。

There were different contamination conditions for different PAHs components in soils. Soils in urban area were severer contaminated by the height-weight-molecule PAHs than soils in agriculture area. However, there were the similar contamination level among different usages soils for the light-weight-molecule PAHs, such as naphthalene and methylnaphthalene.

不同种类的PAHs对不同利用类型土壤的污染情况也不相同，分子量较大的多环芳烃与总PAHs污染情况相似，表现为城市用地的污染程度要明显高于其它类型土壤；但分子量较小的组分，如萘和甲基萘，在不同利用类型土壤中污染程度相近。

The factors that influence the noise performance of lithium-based grease were researched,the cleanliness of grease is merely one of essential conditions to decrease noise,the particle size of lithium soap thickener is smaller,the noise performance of grease is better,and the low viscosity naphthene base oil has good effect to decrease noise,the polymer can improve lubricity and decrease noise.

研究了影响锂基润滑脂噪音性能的各种因素，润滑脂的清洁度只是降低噪音的必要条件之一，锂皂稠化剂的微粒越小，润滑脂的噪音性能越好，低粘度的环烷基油具有良好的降低噪音的效果，高分子聚合物可以改善润滑性能，降低噪音。

The results show that the addition of surfactant shortens induction time and improves formation rate and volumetric proportion, and the volumetric proportion of synthetic hydrate samples can amount to 136~150; the existence of porous medium delays hydrate formation exiguously; the influence of memory effect on gas hydrate formation is notable, the induction time could be shortened by 10~20 times for the experimental system containing residual pentahedral ring structure.

结果表明：表面活性剂的加入缩短了水合物生成诱导时间，提高了生成速度和含气率，合成的水合物样品含气率达到136~150；多孔介质的存在对水合物的生成有较小的延缓；记忆效应对瓦斯水合物生成影响显著，在拥有水合物分解残余五面体环等结构的实验体系中，水合物生成诱导时间缩短10~20倍。

A filtered transformation and a stochastic control Lyapunov design method are applied to Marino-Tomei systems driven by Wiener noises of unknown covariance. A parameter adaptive law and a control law are obtained to ensure that the closed-up systems are noise-to-state stable and the tracking error can converge to a small residual set around the origin in the sense of mean quartic value in average.

通过滤波变换，采用随机控制Lyapunov设计方法，对于受方差未知的Wiener噪声干扰的Marino-Tomei非线性系统，给出了参数自适应律和控制律，使得闭环系统成为噪声--状态稳定的，并且跟踪误差的4次均方值在时间平均意义下收敛到一个足够小的区域内。

This product use special-purpose materials, bear cooling agent, against oil, grinding wheel froth and iron filings and so on; The guard shield has the traveling schedule long and reduces the small merit; Guard shield's bellower speed may amount to the 200m/minute; In the guard shield any metal parts, have not needed to worry the guard shield works when to present the components to become less crowded, but creates the serious broken link to the machine, has the best security.

该产品使用专用的材料，耐冷却剂、防油、砂轮沫和铁屑等等；护罩具有行程长和压缩小的优点；护罩的风箱速度可达200m/分；护罩内没有任何金属零件，不用担心护罩工作时会出现零件松动而给机器造成严重的破环，具有最佳的安全性。

After this research work, we know that: HMCM-22 is a better catalyst of selecting naphthalene alkylation; Surface modification of zeolite Y is effective, but the effect of zeolite 3 is not evident and surface modification doesn"t suits mordenite; Surface modification doesn"t affect the frameworks and inner environments of zeolites, but only reduces diameter of orifice and overlays surface acidities; t-butanol is not suitable for alkylating agent of the reaction using modified zeolites as catalyst; Solvents with smaller molecular size are advantageous for naphthalene alkylation reaction using modified zeolites as catalyst, such as cyclohexane is better than decalin.

通过本论文的研究，我们知道：HMCM-22是萘择形烷基化反应较好的沸石之一；Y沸石的外表面改性效果较好，β沸石则效果不明显，而丝光沸石则不适于外表面改性；外表面改性不改变沸石的骨架结构和孔道内部环境，仅减小孔口直径和覆盖外表面酸性位；叔丁醇不适于作外表面改性沸石催化的反应的烷基化试剂，其反应活性很低，且选择性无明显提升；分子较小的溶剂更适于外表面改性沸石催化的反应，环己烷就明显好于十氢萘。

In order to study the aldol condensation of 2.15-hexadecanedione on the surface of aluminium, the intermolecular condensation mechanism of acetone occurring on aluminum was simulated by using semi-empirical AM1 method embodied in MOPAC 6.0 program package. The optimized structures and geometry parameters of 5 transition complexes and 4 intermediates were given.First, 2 molecules of acetone coordinated with aluminum by electrostatic attraction.One atom of hydrogen of acetone migrated to aluminum because of t...

为了研究2，15－十六烷二酮在氧化铝表面的环合机理，选择小分子丙酮为模型化合物，用量子化学半经验AM1方法研究双分子丙酮在氧化铝表面的醛醇缩合机理，给出了反应过程中的5个过渡态和4个中间体的结构和几何参数，该催化反应可以认为是氧化铝分子与两分子丙酮分子发生静电络合作用，然后借助氧原子的负电荷导致脱氢并实现缩合，根据中间体的能量变化，推测有较稳定的铝复合物生成。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了