查询词典 double-precision

In this thesis, a convenient and efficient synthesis of highly functionalizeddihydropyrido[2,3-d]pyrimidines via a double [5 + 1] annulation strategy startingfrom easily available α-alkenoyl-α-carbamoyl ketene--acetals 1 and cheapreagents (NH4OAc, DMF, and POCl3) has been developed.

本论文探索了一种简便有效的合成高度官能化的二氢吡啶并[2，3-d]嘧啶的方法，此方法由易得的α-乙酰基-α-氨基乙酰基二硫缩烯酮1和便宜的试剂(醋酸铵，二甲基甲酰胺和三氯氧磷)通过两步[5 + 1]加成而实现。

THE FIRST TOTAL SYNTHESIS OF TAXAMAIRIN B Taxamairin B, representive of rare naturally-occuring rearrang-ed 9(10→20)-abeo-8, 11, 13-triene diterpenoids, has been firstsynthesized by a eleven-step route in an overall yield of 8.19%,starting from commercially available catechol and 1,3-cyclohexan-dione. The improved Friedel-Crafts annulation, thermodynamicallycontrolled-geminal pairing methylation, the selective oxidation ofallyl group and the selective reduction of the less-hindrancecarbon-carbon double bond are the key steps.

二。美丽红豆杉素B的全合成研究 1，美丽红豆杉素B的首次全合成以价廉，易得的邻苯二酚和1，3-环己二酮为原料，经过改良的Friedel-Crafts烷基化反应，热力学控制的α，β-不饱和酮结构的α一位双烷基化，烯丙位的选择性氧化，以及选择性还原位阻较小的碳碳双键等十一步反应，以8.19％的总收率首次完成了美丽红豆杉素B的全合成。

The tunable photon broad band radio frequency phaser based on a silicon ring resonance cavity comprises a pumping signal light-generating system, a carrier wave light-restraining double-sideband generating system, a silicon ring resonance system and a measuring system; wherein, the silicon ring resonance system comprises a light coupling device and the silicon ring resonance cavity; the output of the light coupling device is connected with the input port of the silicon ring resonance cavity; wherein, the silicon ring resonance cavity is composed of a silicon annulet and a root of a straight waveguide; the air gap distance between the silicon annulet and the root of the straight waveguide is several ten nanometers or several hundred nanometers; the taking characteristic of the silicon ring resonance cavity is the characteristic of a seasonal reject trap; the transmission rate in the position of a resonance wavelength is equal to zero or is very close to zero.

本发明包括：泵浦信号光发生系统、载波抑制光双边带产生系统，硅基环形谐振腔系统，以及测量系统。所述硅基环形谐振腔系统包括一个光耦合器和一个硅基环形谐振腔，光耦合器的输出连接到硅基环形谐振腔的输入端口，其中：硅基环形谐振腔由一个硅基微环和一根直波导构成，硅基微环和一根直波导之间的空气隙间隔为几十至几百纳米，硅基环形谐振腔频谱特征是周期性的带阻滤波特性，在谐振波长处的透射率等于0或非常接近0。

All of his paintings are presented and interpreted in depth, with The Annunciation and The Last Supper featured on large double-spreads.

值得一看的还有搭配大篇幅跨页的图片深入解析"最后的晚餐"这件作品。

Otherwise, the difference between Emerson and Cather's natural concept was also discussed, that is nature in Cather's eyes is double-faced and eco-central, while Emerson's view of nature is single and anthropocentric.

此外，还谈到了凯瑟自然观与爱默生的不同之处，即凯瑟眼中的自然是双面性的，以生态为中心的，而后者观照自然的视角则是单一的、人类中心的。

Executed double displacement of company assets and worker identity in October 2001, through deepening the reform of system of company property right, straightened relation of belongings, property right, realized; of anthropomorphize of capital, property right to pass the labor relationship that straightens employee, as new as employee establishment new-style labor concerns.

浙江省诸暨市长途汽车运输有限公司的前身是有着50年历史的一家国有运输企业。2001年10月实行了企业资产和职工身份双置换，通过深化企业产权制度的改革，理顺了财产、产权关系，实现了资本、产权人格化；通过理顺员工的劳动关系，与员工重新确立了新型的劳动关系。

Methods In this randomized, double-blind trial, we compared 4 years of therapy with either tiotropium or placebo in patients with COPD who were permitted to use all respiratory medications except inhaled anticholinergic drugs.

该试验为随机双盲试验，我们将COPD患者分为两组，一组为噻托溴铵组，另一组为安慰剂组，可以使用除吸入性抗胆碱能药物外的所有呼吸系统用药；然后比较这两组患者4年的疗效。

The double-blind trial included 34 patients with OAB and confirmed IDO who had failed on a trial of anticholinergic therapy for six weeks or more due to either poor efficacy or tolerability.

这项双盲试验纳入34例OAB具有IDO的患者，这些患者曾行6 周以上的抗胆碱能药物治疗后由于疗效不佳或耐受性差而告失败。

Such single-digit increases may seem anticlimactic for a company that has notched double-digit growth for years.

这种个位数的增幅对于多年来一直保持两位数增长速度的公司来说可能反差过大。

We have successfully made two types of anticorrosive metal coating s, e.g, coating of single and double composition.

我们成功开发了单涂和双涂两种形式的金属防腐蚀涂料产品。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。