管

The formation mechanism of the absolute instability and gyrotron backward wave oscillations is analyzed, and the methods to suppress the parasitical modes are discussed.The nonlinear theory model of gyro-TWT is consummated by considering the influence of tapered magnetic field and waveguide radius, electron velocity spread, and waveguide loss on electron beam-wave interaction. The large-signal characteristic of gyro-TWT, such as launching loss and absolute instability, are also analyzed in detail. This work establishes the foundation for the development of a gyro-TWT amplifier.

重点研究了两段损耗波导结构和损耗陶瓷结构回旋行波管中的电子注-波互作用，分析了绝对不稳定性和回旋返波振荡的形成机制和抑制寄生模式的方法；完善了回旋行波管的非线性理论模型，并考虑了磁场和波导半径渐变、速度零散、波导损耗等因素对注-波互作用的影响；详细分析了发射损耗、相位稳定性等回旋行波管的大信号特征，为回旋行波管放大器的研制奠定了基础。

The method will involve a sequence of ammonification of glass surface, functionalization of carbon nanotube surface, and bonding between the nanotubes.

将奈米碳管与其它材料以一定的比例复合而制备，进而形成一种具有奈米碳管之复合吸附材料所组成之固相萃取柱介质，其合成步骤包括：奈米碳管表面改质官能化，玻璃粒体之载体氨化及最后将两者经缩合剂作用而产生化学键结使奈米碳管批覆在玻璃粒体之载体上。

Since the production of carbon nanotubes synthesized by arc-discharge method contains impurities such as carbon nano-particles, amorphism carbon and graphite fragment, several purification methods were used to purify carbon nanotubes. It is found that with oxidation method in air, we can easily get purified carbon nanotubes.

由于用电弧放电法合成出来的纳米碳管产物中除了有纳米碳管外，还含有一些纳米石墨颗粒、无定形碳和石墨碎片等，因此本文对用电弧放电法合成出的纳米碳管进行了多种方法、探索性的提纯研究，实验结果发现，利用大气氧化法对纳米碳管进行提纯效果好，设备简单，是一种方便实用的方法。

The mechanical property testing shows that the seamless PLLA tubes perform excellent radial strength,which indicates that the mechanical properties of biodegradable stents made of these tubes was supposed to be excellent.PLLA and its composites were first used in preparing seamless tubes as antecedency of laser-cut biodegradable coronary stents in china.Finite element analyses of the biodegradable coronary stent model indicate the explorative design basically meets the requirement of reasonable and applicable stents.There is not such kind of research yet in domestic.Optimum laser-cuttting parameters of CO2 laser was cauculated based on experiential formula,within it,biodegradable coronary stents,especially those with complex structure would be manufacutured from seamless tubes quickly by laser microprocessing with high consistency to the design model.The processing efficiency of the CO2 laser demonstrated in experiential formula by us will play an important guiding role in manufacturing biodegradable stents by laser-processing.Our stents that ascribed to laser-cutted,slotted tube stent are proved to be biodegradable, self-expandable and good biocompatible,basically reach the international level on the aspest of manufacturing procedures and design.

研究结果表明：壳聚糖改性材料综合性能优于纯PLLA，更适合于作为可降解冠脉支架的原材料；自主设计的探索性自膨胀管状闭环型可降解冠脉支架的性能符合冠脉设计要求，设计、验证生物可降解冠脉支架模型的研究在国内还未见报道；制备的改性PLLA无缝管的力学性能优越，可通过激光切割获得冠脉支架，这是国内首次采用聚乳酸材料来制备通过激光加工出可降解冠脉支架的无缝管；二氧化碳激光器加工精度能达到加工要求，加工出来的血管支架名义设计与实测值误差小，实现了冠脉支架、尤其是带有复杂外观设计冠脉支架的快速化、规范化加工，对二氧化碳激光器加工聚乳酸材料的效果研究在国内外属于首创，获得的经验公式对日后的深入研究有重要的指导意义；制备的支架为激光切割管状闭环型冠脉支架，支架外观设计、支架加工手段、支架的性能都基本接近国际水平，支架样品符合设计的理念，可以实现自膨胀功能。

The company was founded in 2000 dedicated to various brands of electronic components distribution, Main: ALTERA, Sanyo, Roma, Toshiba, Samsung, Philips, Pu-cheng, KEC, JRC, NEC, ST, OKI , Hetai, Motorola, RATO, AUK various brands of the world, such as in-line, SMD: IC, II, transistor, varactor, sound of tubes, field effect transistor, single bi-directional Thyristor and various photoemission tube to receive first-class components, widely used in car audio, car amplifier, car / home DVD, VCD, CD, MP3, Tuner tuner, LCD displays, and other fields.

本公司成立于二零零零年，致力于经销各种品牌电子元器件，主营：ALTERA ，三洋、罗姆、东芝、三星、飞利浦、普诚、KEC、JRC、NEC、ST、OKI，合泰，摩托罗拉，RATO，AUK等世界品牌的各种直插、贴片：IC、二、三极管、变容管、音响对管、场效应管、单双向可控硅及各种光电发射管、接收头等元器件，广泛应用于汽车音响、汽车功放、车载/家用DVD、VCD、CD、MP3、高频头调谐器、液晶显示器等领域。

According to the model, the deflection and main pre-brace parameters are illustrated with the Jinsong station of the tenth line in Beijing. It demonstrates that the curve shape of theoretical result, computing result and the on-set measure result are uniform in the main and the change law is similar; that the circumferential space of pipe-roof has a optimum value while satisfying the pre-brace function; that the relation between diameter of steel pipe and flexibility of barrel vault meets negative exponential function. And the diameter of steel pipe has a optimum value.

依据该模型，以北京地铁10号线劲松车站管棚支护为例，着重对管棚的挠度和主要支护参数进行的分析表明：理论结果与计算结果和现场量测结果的曲线形状基本相同，变化规律相似；在满足预支护作用的同时，存在相对较优的管棚环向间距；钢管直径与管棚挠度之间符合负指数函数关系，管径存在最佳值。

Zhu Yuanping, born in Yixing, Jiangsu Province in 1952, has been ardently loved music since his childhood. He has studied to play various traditional Chinese instruments and western instruments. He has studied the bassoon with Mr. Liu Qi, a famous bassoonist. In 1983, he was enrolled to the Strings and Winds Department of Shanghai Conservatory of Music, studying the bassoon with Mr. Zhao Zhun.

CCTV.com消息：朱垣平1952年生于江苏宜兴，自幼酷爱音乐，曾学习过多种民族乐器和西洋乐器，后师从我国著名大管演奏家刘奇先生专攻大管演奏艺术，1983年考入上海音乐学院管弦系，师从赵准先生继续攻读大管专业。

The reticulated vessel which has large cavity has thicker wall due to more elastic fibers and more smooth muscles and its endothelium is cuboidal epithelium which has rotundity karyons. But the reticulated vessel which has small cavity has thinner wall due to less elastic fibers and less smooth muscles and its endothelial cells are flat epithelial cells which have long-shuttle-shaped karyons. In some regions, the ducts are very small in diameter and thin of wall, and they become blood sinus in the end.

管腔大者，管壁厚，弹性纤维、平滑肌纤维多，内膜靠腔面内皮细胞多成立方状，细胞核端位近圆形；管腔小者，管壁薄，弹性纤维、平滑肌纤维少，内皮细胞扁平、排列稀疏，胞核长梭形；一些区域管径极小，管壁极薄，成为开放的血窦，只允许一个血细胞通过。

The results showed that the CNTs have outer diameters of about 60 nm~90 nm and a length of 8 μm, showing straight tubular and chain structures.

结果显示：合成的碳纳米管为多壁碳管；碳纳米管直径60nm~90nm，长度约8μm；碳纳米管展现出中空管状和链状两种结构；碳纳米管的生长采取催化剂底端生长模式。

During past 2 years, we produced milkly white fused quartz tubing, non-ozone quartz tubing, UV stop quartz glass tubing, sunshine quartz tubing on the basis of common quartz tubing, they are widely used in electric industry, electric lamp-house, chemical, nuclear industry, etc, and won users'trust and favorable comments .Our co. also holds advanced full analyse and finished product and detect system. The 2 sets of infrared photometers have being used in the process of producing, and control effectively the content of hydroxy in the quartz products.

公司成立两年多来，在生产普通石英管的基础上，相继推出乳白石英管、无臭氧石英管、滤紫外线石英管、以及太阳光石英管等，广泛用于电子工业、电光源、化学、核工业等领域，深受用户的信赖和好评。

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