单级

When the inverted pendulum inverts up, it becomes a extremely unstable system.

当单级倒立摆倒立起来以后，就构成了一个极端不稳定的系统。

For the model system, the reaction time decreased from 24 h to 7 h at 50 ℃ by adding the surfactant of hexadecyltrimethyl ammonium bromide into the reaction systems, and the sulfur content was detected to be below 10×10^-6 after only oxidation process.

对于实际汽、柴油体系，通过添加表面活性剂，氧化过程中油水相比可从1：1降低为25：1，大大减少了氧化剂用量，且氧化后萃取的单级脱硫率大于50％，优于直接萃取过程的脱硫率。

High frequency emergency lighting apparatus for telecommunication power system is proposed in this paper. The proposed circuit configuration comprises an electronic ballast, a line voltage detector, and a charger/discharger. To compact the system structure and raise the efficiency, the class E inverter and bi-directional converter are employed, respectively.

本文中主要提出一种应用於电信电源供应系统之高频紧急照明装置，所提之架构包括采用E类换流器为主电路之电子安定器、市电侦测电路及单级双向充放电电路，其主要特徵是电路简单、维修容易且具高效能。

What′s the difference between multigrade and monograde engine oils?

多级粘度和单级粘度发动机润滑油之间有什么区别？

In this paper,structure,configuration and function of computer monitoring system for double-line single ship lock of Changzhou Multi-purpose Water Project are studied,and optimal design measures are proposed.

介绍长洲水利枢纽双线单级船闸计算机监控系统的系统结构、配置、功能，并提出设计优化措施。

The rattling model of a one stage gear system is established,in which mass unbalance,speed fluctuation of driving shaft and backlash of the gear pair are considered.

在考虑不平衡质量、主动轴转速波动及齿侧间隙的情况下，建立了单级齿轮传动系统的拍击振动模型。

Then the paper presents a novel-working mode of Boost-Forward single-stage Power Factor Correctors based on the analysis. And get the principle of the conduction mode and the method to control the voltage of the buck capacitor after the analysis of the boundary mode of the PFC converter and the DC-DC converter.

在此基础上，本文首次提出了一种全新的临界工作模式下的单级功率因数校正电路，在对PFC变换器及DC/DC变换器工作在连续及不连续的边界条件进行了讨论后，得出了电路工作状态的精确解并提出了控制储能电容电压的临界点工作方式。

In the material world this is quite exceptional because magnetic particles are usually observed as dipoles, north and south combined.

在物质世界这是非常独特的，因为磁性粒子通常观察到的是南极和北极，并且都是结合在一起的，然而有几个理论预言了磁单级子的存在。

Applying the theories of thermodynamics and mechanics, the working process of basicAPE--single-stage expansion, is analyzed and its related mathematicmodel is built up. The simulation methods based on this model are discussed, which is the preparation for the later research work.Chapter 3: The working characteristics of the single-stage expansion engine are researched on by the simulation.

运用热力学和力学理论对最基础的气动发动机——单级膨胀气动发动机的工作过程进行了研究分析，建立了相应的数学模型，讨论了应用该模型对气动发动机进行理论分析的仿真计算方法，浙江大学博士学位论文：气动发动机探索性研究为后续理论研究打下基础。

Nearly all multigrade engine oils will contain viscosity index improvers, monograde oils do not contain these additives.

几乎所有多级粘度发动机润滑油都含有粘度指数改进剂，单级润滑油则不含有这些添加剂。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。