A novel technique to prepare LiNbO3 at low temperature

Fresh niobium hydroxide was first precipitated from NbF₅ solution using an aqueous ammonium hydroxide under basic conditions. Then a simple procedure of mixing lithium and niobium hydroxides together and heating at a low temperature (400 °C) produced pure ultrafine single phase LiNbO₃ (LN). In the literature, this is the lowest temperature so far reported on the formation of LN. The phase content and lattice parameters are determined by X-ray diffraction (XRD). The average particle size and morphology were studied by transmission electron microscopy (TEM).     

Characterization of two-phase nickel aluminides produced by pressure-assisted combustion synthesis

Two-phase (B2+L1₂) nickel aluminide intermetallic compounds were synthesized by the pressure-assisted volume combustion synthesis (CS). The production and characterization of the samples containing NiAl+Ni₃Al were investigated. Aluminum (99% pure, 15 μm) and carbonyl nickel (99.8 pure, 4-7 μm) powders were used. The production of intermetallic compound was carried out at 1050 °C under 150 MPa uniaxial pressure in open air atmosphere in an electrical resistance furnace for 60 min. The formation temperature of intermetallic compound was determined by differential scanning calorimeter (DSC) analysis, and exothermic temperature of powder mixture was determined as 653 °C. The characterization of samples was confirmed by optical microscope, SEM and XRD analysis. It was observed that the structure of compound has very low porosity and the formation of NiAl was completed successfully. The relative density of test materials measured according to Archimedes’ principle was 98.04%. The microhardness of test materials was about 351 HVN₁.     

泥土中微量六氯环戊二烯的气相色谱分析

采用SE 3 0为固定液进行色谱柱分离 ,用外标定量法测定泥土中的微量六氯环戊二烯 ,结果最小检知量为 0 .18× 10 - 6 ,相关系数为 0 .99992。     

巴彦浩特探区钻井液技术初探

巴彦浩特探区钻井液工艺技术的重点是，解决疏松砂砾岩地层水涌漏同层、侏罗系地层水的HCO3^-污染及可能出现的火成岩地层井塌复杂。结合内蒙古巴彦浩特探区地层和井身结构特点，采用了两性聚合物／氯化钾钻井液和氯化钾／石膏-聚磺钻井液体系。该体系抑制能力强，性能稳定．容易实现低固相、低密度近平衡钻井，保护储层效果好。对复杂情况采取了有针对性的处理办法：平稳操作和合理的钻井工程措施是预防水层涌漏同层和火成岩井塌复杂的重要手段；用井场易得的固井水泥或石膏配合烧碱处理HCO3^-污染简便易行；处理火成岩井塌复杂，控制合适的钻井液性能是必要的。     

Behaviour of ±45° glass/epoxy filament wound composite tubes under quasi-static equal biaxial tension–compression loading: experimental results

The primary aim of this paper is to present results describing in detail the behaviour of ±45° E-glass/MY750 (GRP) tubes, of various wall thicknesses, subjected to equal biaxial tension–compression loading, generated under combined internal pressure and axial compression. The role played by the non-linear lamina shear has also been assessed by comparing various shear stress–strain curves for embedded laminae (extracted from tests on ±45° tubes subjected to circumferential: axial stress ratios SR=1:0, 1:−1 and 2.3:−1) with that of an ‘isolated’ lamina (measured from torsion of 90° tubes). Extracted shear failure strains, for embedded laminae, were more than four fold larger than those measured at ultimate failure for an ‘isolated’ lamina. Soft characteristics were observed in the embedded lamina and these were believed to be due to interaction between early matrix damage initiation (and propagation) and shear. Factors affecting the behaviour of the tubes, such as bulging, scissoring, thermal stresses and stress variation through the thickness are discussed.     

纤维体积分数对K3D/MCPA复合材料力学性能的影响

本文研究了纤维体积分数对三维编织芳纶纤维增强铸性尼龙(简称K3D／MCPA)复合材料力学性能的影响。研究表明，K3D／MCPA复合材料有优异的抗冲击性能，冲击强度比三维编织芳纶纤维增强铸性尼龙(简称C3D／MCPA)和纯基体均有大幅度的提高，且随着纤维体积的提高而升高。K3D／MCPA复合材料剪切强度随纤维体积比的增大而增大，其纵向剪切强度低于纯基体和C3D／MCPA复合材料，但其横向剪切强度高于它们。K3D／MCPA复合材料弯曲强度与弯曲模量随纤维体积比的提高而提高，但与相同体积比的C3D／MCPA相比，K3D／MCPA的弯曲强度与弯曲模量均较低。     

武钢 10000 m3/h制氧机主冷泄漏故障处理及应急保产方式

氧气生产单位保用户用气一旦出现较为紧张的局面时，如何正确处理保安全生产运行、保用户生产、安排抢修时间三者之间的关系，值得关注与研究。     

Localization of Function Within the Dorsal Hippocampus: The Role of the CA3 Subregion in Paired-Associate Learning.

Computational models and electrophysiological data suggest that the CA3 subregion of the hippocampus supports the formation of arbitrary associations; however, no behavioral studies have been conducted to test this hypothesis. Rats with neurotoxin-induced lesions of dorsal dentate gyrus (DG), CA3, or CA1 were tested on object-place and odor-place paired-associate tasks to test whether the mechanism that supports paired-associate learning is localized to the CA3 subregion of the dorsal hippocampus or whether all hippocampal subregions contribute to paired-associate learning. The data indicate that rats with DG or CA1 lesions learned the tasks as well as controls; however, CA3-lesioned rats were impaired in learning the tasks. Thus, the CA3 subregion of the dorsal hippocampus contains a mechanism to support paired-associate learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

油墨用聚氨酯胶粘剂的性能研究

主要研究用于印刷油墨的单组分溶剂型聚氨酯粘合剂，考查聚合物多元醇类型对树脂微观形态、机械性能以及印刷适应性和附着性等性能的影响。研究结果表明，聚酯型树脂的微相分离程度低于聚醚型，具有较好的机械性能、印刷适应性和附着性。     

苯乙烯与1-(2-叔丁基过氧异丙基)-3-异丙烯基苯共聚行为研究

苯乙烯与1－（2－叔丁基过氧异丙基）－3－异丙烯基苯（D120）能进行自由基共聚合反应，聚合后过氧基团以侧基的形成被保留在共聚物大分子链上，凝胶色谱分析发现，随原料单体中D120比例增加，共聚物的分子量减小，分子量分布变窄，DSC分析发现共聚物中过氧基团的分解温度随D120结构单元含量的增加而下降，但仍高于D120单体过氧基团的分解温度，苯乙烯与D120的竞聚率为：rD120=0.700,rSt=0.714。