等环的

Focused on many problems existing in pressure control system of drilling pipe friction welding,such as high failure rate and poor amenability,the basic principles of friction welding and electro-hydraulic proportional technique were briefly described.

针对焊接钻杆连续驱动摩擦焊机采用开关阀组成压力控制系统存在故障几率高、可控性差等问题，将电液比例控制技术应用在摩擦焊压力控制中，实现了摩擦焊轴向压力闭环控制、滑台进给速度的开环控制；可对摩擦焊机主轴速度、轴向压力、轴向缩短量、主电机电流、油温等进行实时检测。

Then Doripenem came into the market in the July ,2005. We studied the synthesis of Doripemen.Firstly, we synthesized the chemical 2 from the starting material------o-hydroxylphenylacylamine through Reformastky reaction, alkylation, Diekmann reaction, enolization, esterification and etc. Secondly, we synthesized the chemical 3 from L — hydroxylproline through the protection of carboxyl, amidogen and hydroxyl group, reduction by NaBr, SN_2 substitution and Mitsumobu reaction.

我们以水杨酰胺为起始原料，经Reformatsky反应、烷基化、Diekmann环合、烯醇化、酯化等反应合成双环母核2；再从L-羟基脯氨酸出发，经酯化保护羧基、保护氨基、保护羟基、硼氢化还原酯得醇、Sn2取代和Mitsumobu反应等合成巯基侧链3；最后由化合物3经脱保护、水解得硫醇，和化合物2在二异丙基乙基胺的作用下缩合，最后Pd／C催化脱保护，历经16步反应最终得到产物多尼培南。

Caffeine - A derivative of coffee, is an efficient arouser of central nervous system capable to drive away fatigue, and improve renal circulation. Its stimulation on the cerebral cortex activates Neurotransmitter receptors in the cell membrane; the adenylyl cyclaseactivated on the other surface of the cell catalyzes Adenosine Triphosphate, forming Cyclic adenosine monophosphate, and thus set off series of bio-chemical reactions, like increase of passionate feel, prompt recovery from fatigue after working etc..

咖啡因—由于咖啡本身具有兴奋神经中枢，消除疲劳，增加肾脏血流量的作用，通过对大脑皮层的刺激，使神经递质作用于细胞膜受体，激活了膜另一侧的腺苷酸环化酶，被激活的腺苷酸环化酶催化三磷酸腺苷环化酶，被激活的腺苷酸环化酶催化三磷酸腺苷形成环磷酸腺苷，从而引起一系列生化反应，如增加愉快感和消除事后疲劳等。

So in chapter 2, we use P-flat and P-injective modules to characterize some important rings, like SF-rings, Von Neumann regular rings and Coherent rings, etc. In chapter 3, we introduce the homological dimension of P-flat and P-injective modules.

众所周知，正是由于研究各类模以及它们的同调维数，人们才能对环得到更深层次的性质的描述，所以在第二章中，我们就利用了P-平坦模与P-内射模来刻划几种重要的环，如SF环、Von Neumann正则环、凝聚环等。

Author had started the research on design and synthesis of heterocycles several years ago, mainly focused on the design and synthesis of imidazole, thiazole, tetrazole derivatives and their glucosides, in which most of them may have some particular bioactivities.

本论文主要是围绕具有生理活性含氮杂环化合物的设计与合成而展开的，在论文工作中我们应用液相"一锅法"和固相组合化学方法进行了咪唑环、噻唑环、四氮唑环等具有生理活性的杂环化合物及其糖苷的合成。

Author had started the research on design and synthesis of heterocycles several years ago, mainly focused on the design and synthesis of imidazole, thiazole, tetrazole derivatives and their glucosides, in which most of them may have some particular bioactivities.

本论文主要是围绕具有生理活性含氮杂环化合物的设计与合成而展开的，在论文工作中我们应用液相&一锅法&和固相组合化学方法进行了咪唑环、噻唑环、四氮唑环等具有生理活性的杂环化合物及其糖苷的合成。

Get conclusion:(1 ) the Taihu around region holding basketball game have the advantage;(2) the Taihu around region holding basketball game to have the developping(;3) in Taihu around region farmer basketball game hold worse (4) in Taihu around region basketball sport develop, the game opens exhibition existence the difference of the region;(5)School basketball game opens the exhibition aspect high school not to make widely available, the high level ball team is too little; The high school is more universal, but Be valuing with support"s degree not enough(;6) region of officers and workers" basketball game hold is different greatly and not universal(;7) the Taihu around basketball league match hold more and successfully, but Be taking part in a game a troops and contesting way, ball team real strenght, sponsor company...etc. to still exist some problems, influence the quality of league match development.

得出结论：(1)环太湖地区开展篮球赛事有其优势性；(2)环太湖地区开展篮球赛事有其持续性；(3)环太湖地区农民篮球开展较差；(4)环太湖地区的篮球运动发展，赛事开展存在地域的差异性；(5)学校篮球赛事开展方面高校不普及，高水平球队太少；中学较普及，但在重视和支持程度不够；(6)职工篮球赛事开展地域的差异性大，不普及；(7)环太湖篮球联赛举办较成功，但在参赛队伍、竞赛办法、球队实力、赞助商等方面还存在一些问题，影响联赛发展的质量。

Macrocyclic supramolecular drugs forming by macrocycle s with special structure and high selectivity according to their different purpose could play important parts in the drug-controlled releasing, chiral recognition, mimic enzyme, molecular switch, and so on, especially supramolecular drugs can help to improve solubility, bioavailability of drugs and realize targeting when it encapsulates drugs.

具有独特的结构和高选择性的大环化合物所形成的大环类超分子药物可根据其目的不同在药物控制释放、手性识别、模拟酶、分子开关等方面起着重要作用，能大大改善药物的溶解度、生物利用度及实现靶向作用等，因此大环超分子药物为化学药物治疗提供了新的推动力。

This research applies the micro forming process with other mass production techniques to construct the key components of the micro/meso gear transmission. The final prototype is the planetary gear transmission with outer diameter 6mm and gear module less than 0.15mm developing in 3 years. The purposes and developing technologies of this project are as follows: 1. setting up the design and analysis of parts and system; 2. the mold design of gear and planet plate; 3. assembly modules of planetary gear train; 4. inspection of gear profile and gear train; and 5. heat treatment of micro parts.

本研究将以精微成形技术搭配其他量产制程，逐步开发微型减速机内的所有关键零件，预计在3年内最终完成外径≦ψ6mm、齿轮模数m≦0.12mm之的行星式齿轮减速机的开发，研发目标包含有微型传动系统结构/机构与零组件设计分析技术，试量产型精微行星/太阳齿轮、传动盘、环齿轮等原型件模具设计与开发，行星臂、太阳齿轮、行星齿轮与环齿轮等组装模组技术，微型齿轮齿形及相关微型齿轮箱检测技术，以及精微元件热处理技术等关键技术。

To overcome the drawbacks in the weight and cost of the antenna with the corrugated soft surface, a new patch antenna with patch rings is designed. Its weight is about 1/4 less than the antenna with the corrugated soft surface and it is inexpensive. Good experimental results are obtained. The radiation pattern of the antenna is more rotationally symmetric, and a more reduction on the sidelobe levels of the antenna is achieved as compared to the antenna with the corrugated soft surface. In conclusion, in the present thesis both theoretical and experimental research works have been carried out intensively on patch antennas based on photonic-bandgap structures.

为了克服皱褶软表面天线份量重，加工费用贵等缺点，我们对空气介质的皱褶圆环结构软表面天线进行了改进，将周期分布的皱褶圆环平面化，并保持结构的软表面特性，设计出了一种新的平面圆环结构的软表面天线并进行了实验研究，加工的平面圆环结构天线比皱褶圆环结构天线重量减轻了约1/4，加工费用大大降低，所取得的实验结果显示，该平面圆环结构软表面天线的方向图的轴对称性得到了改善，在俯仰角从0°～-90°的范围内天线H面的波束与E面重合，与皱褶圆环结构相比，天线的旁瓣和背瓣受到了更大的抑制，E面方向图上+120°方向的旁瓣被明显削弱。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。