2—甲基—3—（2—呋喃基）—2—丙烯—1—醇的合成

本文报导了一种新醇分子的设计和合成。它是合成几种新拟除虫菊酯的中间体，作者认为，着眼于醇结构的改变以提高拟除虫菊酯的挥发性，增强药效。该化合物具有分子结构简单，分子量小、易合成的特点，目前，该醇尚无文献报道。     

3—甲基—2—（4—氯苯基）丁酸—2—甲基—3—（2—呋喃基）—2—丙烯酯的合成

本文报道了一种新的拟除虫菊酯分子的设计及合成，这种新化合物具有结构简单，光稳定性好和易合成的特点。它由３－甲基２－（４－氯苯基）丁酸和自制的２－甲基－３－（２－呋喷基）－２丙烯醇经酯化而成。酯化产率为８４％。     

5—（2—硫甲基—4—甲基—5—嘧啶基）—2,4—戊二炔—1—醇α甲基丙烯酸非线…

聚二乙炔类化合物在超快合光开关、逻辑门和远距离通讯系统的多路传输等方面有着潜在的应用前景。但并不是所有的ＰＤＡ都能用于这些方面，它的选择应当考虑聚合性能，链密度，共轭度、溶解性、热稳定性及可加工性等方面的因素。     

新西兰——独树

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新西兰——霞光

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光引发剂1—对吗啉苯基—2—二甲氨基—2—苄基—1—丁 …

本文合成了１－对吗啉苯基－２－二甲氨基－２－苄基－１－丁酮,将合成产品与国外同样产品的物理性质及结构表征进行了对比,并对产品的光引发性能进行了初步测试。     

2—叠氮—1萘醌—5—磺酸生产工艺优化

研究以L-酸为原料,对合成用于制作PS版的2-叠氮1-萘醌-5-磺酸的亚硝化、还原及重氮化三步生产工艺进行最佳配比选优试验。结果表明对L-酸的总收率可达73-75％.获得了较高的收率。     

钕在Ti—Al—Sn—Zr—Mo—Si—Nd耐热钛合金中的存在形态

在采用常规冶金工艺的Ti—Al—Sn—Zr—Mo—Si—Nd合金中,绝大部分钕是以富钕第二相存在的。SEM、TEM、X射线衍射、能谱分析和电子探针试验表明:富钕第二相呈球形或椭球形,其成分由Nd、Sn和O组成,Nd和Sn的原子含量比约为3:2,其结构为体心立方,而且与基体非共格。     

Structural analysis of high-T c cuprate superconductors

We have shown in this paper that members of the Tl-Ba-Ca-Cu-O and Bi-Sr-Ca-Cu-O superconducting families fabricated so far are built up of superconductor-semiconductor arrays. Four general homologous series are written down for these two families. The basic fundamental block in each series is itself a superconductor. We suggest that the Y-Ba-Cu-O family has a similar characteristic if YBaCu₂O_5-d is a superconductor.     

Composite microstructures in the Bi-Sr-Ca-Cu-O system

We report a detailed microstructural study of red phases obtained in the crystal growth of the 2212 superconductor from Bi-Sr-Ca-Cu-O melts (Bi : Sr : Ca : Cu = 4 : 3 : 3 : 4 or 2 : 2 : 2 : 4) during cooling from 1000–1050°C. Crystallization from temperatures well above 1000°C leads to quantitative formation of red crystalline agglomerates containing an ordered array of rod-shaped Cu₂O inclusions embedded in a Bi₁₆(Sr,Ca)₁₄O _x matrix. The separation between the rods is 1.5–2 μm, their diameter is less than 1 μm, and their length is on the order of 15 μm. The observed atomic ordering is interpreted in terms of a eutectic model. Lowering the homogenization temperature notably reduces the amount of the eutectic or prevent its formation. In the latter case, a mechanical mixture of fine-particle Bi-Sr, Bi-Ca, Bi-Sr-Ca, and Cu oxides is formed. The effect of the red phase on the structure of the 2212 crystals is examined. Quantitative formation of rod-eutectic grains during 2212 crystal growth suggests that the growing crystals contain many stacking faults in the form of 2201 intergrowths.     

Structural analysis of high-Tccuprate superconductors

We have shown in this paper that members of the Tl-Ba-Ca-Cu-O and Bi-Sr-Ca-Cu-O superconducting families fabricated so far are built up of superconductor-semiconductor arrays. Four general homologous series are written down for these two families. The basic fundamental block in each series is itself a superconductor. We suggest that the Y-Ba-Cu-O family has a similar characteristic if YBaCu₂O_5-d is a superconductor.     

Casting high-Tcsuperconducting BiSCCO

Bi-Sr-Ca-Cu-O (BiSCCO) was melted and cast into molds in order to render the superconductor into fully dense and useful shapes. Special conditions for casting and subsequent heat treatments were required to ensure structural integrity and a high transition temperature,T _c .The history of the castings during heat treatments was studied by thermal analysis, X-ray diffraction, and microscopy.     

Casting high-T c superconducting BiSCCO

Bi-Sr-Ca-Cu-O (BiSCCO) was melted and cast into molds in order to render the superconductor into fully dense and useful shapes. Special conditions for casting and subsequent heat treatments were required to ensure structural integrity and a high transition temperature,T _c .The history of the castings during heat treatments was studied by thermal analysis, X-ray diffraction, and microscopy.     

Critical current density and magnetization studies on Bi(Pb)SrCaCuO

HighT _c phase (T _c ∼ 110 K) has been obtained in Bi-Sr-Ca-Cu-O system by partially substituting Bi by Pb. Magnetic hysteresis has been measured as a function of temperature. Critical current densities have been measured at 77 K both by transport and a.c. magnetization method in bulk samples for various concentrations of Pb. The results show that substitution of 15 at % Pb for Bi is most preferable for higher critical current density.     

FORMATION OF YBaCu-O SYSTEM SUPERCONDUCTOR BY THERMAL SPRAYING

The YBaCu-O and Bi(Pb)SrCaCu-0 system superconductor coatings by thermal spraying are described. YBaCu-O system superconductor coatings are sprayed by using perovskite type and non-perovskite type powders. As sprayed coatings are not superconducting and there is no perovskite structure even when perovskite type powders are used, but they become superconducting after heat treatment in air. An electrochemical method was also employed, to obtain a high quality superconductor applying an electric field treatment. Bi(Pb)SrCsiCu-0 system superconductor coatings are sprayed by changing the starting composition. As-sprayed coatings were not superconducting, but they become superconducting after heat treatment in air like the YBaCu-O system. The Tc of the sprayed coatings using (Bi_1-xPb_x)₅Sr₃Ca₂Cu₃-O powders is higher than the Tc of sprayed coatings using (Bi_1-xPb_x) ₂Sr₂Ca₂Cu₃-O powders.     

高温超导直接冷却中AlN与Bi-2223间界面热阻的实验研究

基于微结构低温工程学，提出三维低温界面层的概念，指出界面热阻是制冷机直接冷却超导磁体需要解决的关键技术之一。以GM制冷机为冷源，按稳态热流法原理测量了Bi-2223、AIN的热导率及它们之间的低温界面热阻。在0.15MPa-0.55MPa压力范围内，AIN和Bi-2223间的界面热阻随界面层温度和接触压力的升高而降低，并随接触界面处温度的不同表现出不同的变化率。当界面层Bi-2223侧温度为55K时，在0.5469MPa的接触压力作用下，Bi-2223和AIN间的界面热阻是厚度为10mm的AIN垫片体积热阻的38.86倍，是接触压力0.2281MPa时界面热阻的38.7％。     

High-temperature properties of the Bi-Sr-Ca-Cu-O system: Simultaneous occurrence of melting, oxygen desorption, and a metal-insulator transition

We have investigated the temperature dependence of the electrical transport and the thermogravimetric properties, from -200°C to +1000, of the Bi-Sr-Ca-Cu-O high-temperature superconductor. We conclude that this system has a cooperative, simultaneous-melting/oxygen desorption/metal-insulator transition that occurs near 900°C. We speculate on its nature and on its relationship to phenomena found in other high-T _c superconductors.     

Stress characterization of Si by near-field Raman microscope using resonant scattering

We have developed a tapping-mode scanning near-field optical Raman microscope (SNORM) with a caved and pyramidical probe, using resonant Raman scattering, and have measured the stress distribution of Si. The peak frequency shifts to a lower frequency by 0-0.5 cm(-1) in the area covered by silicon dioxide, whereas it shifts to a higher frequency by 0-0.3 cm(-1) in the area uncovered by silicon dioxide, showing that the areas covered and uncovered by silicon dioxide are under tensile and compressive stresses, respectively. It has been found that compressive stresses of about 0.69 GPa/cm2 are concentrated on the corner of the area uncovered by silicon dioxide. The comparison of stress distributions measured with and without the cantilever shows that the SNORM we developed has a spatial resolution of at least less than 250 nm.