Thermal Expansion Behavior of La1—xSrxMn1—yCoyO3—δ Perovskites

The thermal expansion behavior of La1-xSrxMn1-yCoyO3-δ (x=0.2-0.4, y=0.1-0.3) perovskites in air has been investigated. The average linear thermal expansion coefficients increased with increasing Sr content up to 40 mole fraction or Co content up to 30 mole fraction. The expansion is generally attributed to an increase in the average cation radius as some of the cations in the perovskite are reduced in valence when oxygen ions are removed from the structure.     

Enhancement Effect of Gold Nanoparticles on the Bioactivity of Hydrogen-producing Microbe

1 IntroductionGold nanoparticles have attracted considerable atten-tionin manyfields duetotheir some special properties al-though goldis very popularfor beingchemicallyinert[1-3].For example ,gold nanoparticles as amplificationtags havebeenthe subject of research directed at gene analysis[4]and antibody or antigen detection[5-7]due to the large di-electric constant ,ease of preparation,andits biocompati-bility[8].Nanoparticles in the range of 1-10 nmin diameterwould display electronic structur…     

Giant Monopole Resonance and Symmetry Energy

Nuclear matter incompressibility is discussed by the framework of a fully consistent relativistic random phase monopole compression modes in nuclei in the approximation, based on effective Lagrangians with a mixed isoscalar-isovector nonlinear coupling term. A predicted value of the matter incompressibility coefficient is given by comparison between experimental and calculated energies of the isoscalar giant monopole resonance （ISGMR） in nuclei ^208Pb, ^144Sm, ^116Sn and ^90Zr.     

Preliminary Design of In-Pile High Temperature High Pressure Test Loop

Preliminary design of in-pile high temperature high pressure （HTHP） test loop is one of application items at China Advanced Research Reactor （CARR）. The design content is to confirm design parameter, the system flow, standard equipments and layout of equipments according to permitting construction space, specific request of pipeline and equipment for test loop. The files about regulation and general outline are compiled and relative tests are presented.     

综合利用矿产资源的生态和经济价值

综合利用矿产资源是合理利用自然资源和保护环境的一个重要问题。开发自然资源企业的经营取决于它们的生产能力，被利用天然资源的成分和质量，还有社会对其最终产品的需求。为了企业顺利和长远的发展，除了完成生产任务外，企业应该制定与珍惜、综合利用和回收自然资源、推广和采取对自然有保护的工艺和措施、寻找用已有的自然资源生产新的商品来促进消费市场的发展等有关的战略发展方向。废物利用是合理利用自然资源的方向之一。众所周知，矿山开来领域所产出的废物约占总开采量的3／4，而这些废物的很大部分是其他领域生产的好原料。例如…     

内陆钢公司4号转炉车间出钢口寿命的延长

内陆钢公司４号转炉车间出钢口寿命的延长［美］Ｍ．Ａ．Ｔｉｎｄｙａｌａ等１前言氧气顶吹转炉出钢口的使用寿命影响着转炉的利用率、耐火材料的费用以及钢材的质量。在转炉出钢口的套管内径变得过大、而且套管的长度以及出钢时间缩短时，则需更换出钢口。导致上述变化的...     

Optimization of signal detection in SPECT

Parallel-hole collimators of varying design are discussed, using the display signal-to-noise ratio of R.F. Wagner et al. (Med. Phys., vol.6, p.83-94, 1979) to obtain contrast-detail diagrams and analytical expressions for the signal-to-noise ratio in SPECT (single-photon-emission computed tomography). It is concluded: (1) that the detectability of deeply embedded small objects (more than ~10 cm deep) may be improved only slightly by improvements in the resolution and geometric efficiency of parallel-hole collimators; (2) that a long-bore collimator outperforms a low-energy general-purpose collimator for objects smaller than ~2 cm, but only to a minor degree; and (3) that for improvement of small object detectability by SPECT, the most fruitful technological pursuit would probably involve development of focused collimators.