查询词典 ND

A colliding pulse mode-locked unstable resonator Nd: YAG laser is designed, which consists of an antiresonant ring and a convex mirror.

设计由抗共振环和凸面反射镜组成的对撞脉冲锁模非稳腔Nd：YAG激光器。

Petrological,geochemical and Nd,Sr,Pb isotopic studies indicate that the ore-hosting volcanic rocks of Xiongcun supperlarge copper-gold deposit in the Gangdese copper belt, Tibet belong to dacite porphyry with ultro-shallow emplacement.

岩石学、地球化学和Nd、Sr、Pb同位素研究表明，西藏冈底斯铜矿带雄村特大型铜金矿床的容矿火山岩为一套具超浅成侵入特点的英安斑岩，SiO2含量集中在61.97%～64.31%之间，富Na2O、低K2O， Na2O/K2O比值平均为5.25。

By using both the hydrogen decrepitation and double-alloy processes to avoid soft magnetic Laves phase,we prepared N35AH sintered Nd-Fe-B permanent magnet with ultra-high coercivity,which can be used at temperature up to 240℃.

现在汽车驱动电机、水力风力发电机、压缩机电机、船舶用大功率推进电机等领域对高使用温度烧结Nd-Fe-B磁体的需求日益增长，所以提高烧结材料的耐热性成为当今钕铁硼行业的主要研究方向之一。

Light output analysis tests character of spectrum radiate of pyrotechnic mixtures and analyses wave band distribute of light by comparing different static blaze spectrograms of the pyrotechnic mixtures. Screen out the better pyrotechnic mixtures according to request of pumping source. Press experiments in airtight erupt container experiment, which simulate the circumstance that pyrotechnic mixtures deflagrate in quartz pipe, realize the press influence to the quartz pipe wall and the disciplinarian of axes press variety. Apply these pyrotechnic mixtures to Nd:YAG lasers as the pumping source and compare pumping efficiency of different pyrotechnic mixtures. Pumping efficiency is an important standard which checkout if these pyrotechnic mixtures are the better pumping source. Sensitivity experiment analysis incarnate security of pyrotechnic mixtures that is the essential parameter in the process of design, manufacture and use.

通过对烟火药的热分析(爆热分析、DTA、TG)，了解备选烟火药反应过程中的能量输出特性及反应过程中的物理、化学变化规律；光输出分析实验对烟火药配方光谱辐射特征进行测试，比较其静态火焰光谱图，分析不同烟火药剂光辐射波段分布特征，根据激光泵浦源的辐射要求，进而筛选更符合激光泵浦源药剂要求的烟火药；模拟烟火药在石英管中爆燃环境的密闭爆发器压力分析实验反映了烟火药在石英管中反应时对管壁的压力影响以及管内轴向压力变化规律；将烟火药作为泵浦源应用于Nd：YAG固体激光器，比较不同烟火药的泵浦效率，作为检验烟火药是否适合作为激光泵浦源的重要标准；感度实验分析体现了各种烟火药的安全性，是烟火药设计、制造和使用的必要示性数。

The influence of Ce, Nd and Sr on the as-cast microstructure of AZ91 alloy was investigated by optical microscope、scanning electron microscope、electron probe microscope analyzer、differential thermal analyzer and X-ray diffract analyzer, et al.

本文以目前使用最广泛的AZ91镁合金为研究对象，分别添加不同含量的稀土元素Ce、Nd和碱土元素Sr，研究了三种元素对AZ91镁合金微观组织和腐蚀性能的影响。

Analyzes the performane of plane concave resonators with internal thermal lenses and gives out stability and unstability regions in terms of dioptric. Based on the stable and unstable resonators′ characteristics,a detailed analysis for output power of cw plane concave Nd:YAG laser is presented.

光泵Nd：YAG激光器的热效应会在YAG棒中引起轴向热伸长和径向折射率梯度，从而产生激光介质的热透镜效应，有关内含热透镜的谐振腔的研究已有许多报道［1～2］，但基本上都是研究谐振腔的热稳性，对输出功率特性的研究报道很少。

Study on uniform of pump distributivity in a LD side-pumped Nd:YAG laser .

LD侧面抽运的Nd：YAG激光器抽运均匀性研究。

Study on uniform of pump distributivity in LD side-pumped Nd:YAG laser .

LD侧面抽运的Nd：YAG激光器抽运均匀性研究。

This invention discloses a preparation method for anti-corrosion rare earth magnet material characterizing that it takes the optimized grain-boundary phase design as the starting point on the basis of a dual alloy method to select Nd base alloy with high crystal forming ability as the assist alloy and reduces the temperature of the press mold blank in a quartz container to room temperature from over grain-boundary phase melting point with the water extraction way to get enough cooling rate and guarantee the non-grain-boundary phase, compared with the material of the same composition prepared by ordinary method, the weightlessness of this invented material reduces over 30% after testing the weightlessness of the material by laying it for 96 hours under 121deg.C, 2 atmosphere and 100% humid environment to show the advanced performance of anti-corrosion.

本发明公开了一种耐腐蚀稀土永磁材料的制备方法，其特征是它在双合金法制备工艺的基础上，以优化晶界相设计为出发点，选取具有较高非晶形成能力的Nd基合金为辅合金，并在烧结回火时将置于耐高温石英容器中的压型坯件，从晶界相熔点以上以水淬冷却的方式降温至室温，以达到足够的冷却速率，确保得到非晶晶界相，根据本发明制得的耐腐蚀稀土永磁材料，通过测量在121℃、2个大气压以及100％湿度环境下放置96小时后材料的失重情况，结果显示本发明得到的材料与常规方法制备的相同成分的稀土永磁材料相比失重减少了30％以上，充分证明其具备了更优越的耐腐蚀性能。可广泛应用于电子、汽车、计算机、电力、机械、能源、环保、国防、医疗器械等领域。

objective to observe the long-term clinical effects of nd: yag laser in the treatment of epistaxis.

目的 nd：yag激光治疗鼻衄的远期疗效。

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。