场头机械——扫场机

近年来．我国国有农场场头晒粮机械化有了长足的发展．场头粮食的堆、翻、扒、扬、输送、装包等都实现了机械化作业，但扫场问题一直无法用机械来替代。江苏新洋农场十二支场王维虎同志成功地研制了首台扫场机．已获得国家专利。

Morphology and growth of porous anodic oxide films on Ti-10V-2Fe-3Al in neutral tartrate solution

Porous anodic oxide films were fabricated galvanostatically on titanium alloy Ti-10V-2Fe-3Al in ammonium tartrate solution with different anodizing time.Scanning electron microscopy(SEM) and field emission scanning electron microscopy(FE-SEM) were used to investigate the morphology evolution of the anodic oxide film.It is shown that above the breakdown voltage,oxygen is generated with the occurrence of drums morphology.These drums grow and extrude,which yields the compression stress.Subsequently,microcracks are generated.With continuous anodizing,porous oxides form at the microcracks.Those oxides grow and connect to each other,finally replace the microcrack morphology.The depth profile of the anodic oxide film formed at 1 800 s was examined by Auger electron spectroscopy(AES).It is found that the film is divided into three layers according to the molar fractions of elements.The outer layer is incorporated by carbon,which may come from electrolyte solution.The thickness of the outer layer is approximately 0.2-0.3 μm.The molar fractions of elements in the intermediate layer are extraordinarily stable,while those in the inner layer vary significantly with sputtering depth.The thicknesses of the intermediate layer and the inner layer are 2 μm and 1.0-1.5 μm,respectively.Moreover,the growth mechanism of porous anodic oxide films in neutral tartrate solution was proposed.

Biomedical X-ray Imaging Enabled by Carbon Nanotube X-ray Sources

Although discovered more than 100 years ago, X-ray source technology has evolved rather slowly. The recent invention of the carbon nanotube （CNT） X-ray source technology holds great promise to revolutionize the field of biomedical X-ray imaging. CNT X-ray sources have been successfully adapted to several biomedical imaging applications including dynamic rnicro-CT of small animals and stationary breast tomosynthesis of breast cancers. Yet their more irnportant biomedical imaging applications still lie ahead in the future, with the devel- oprnent of stationary rnulti-source CT as a noteworthy exarnple.

Formation mechanism of subtrenches on cone-shaped patterned sapphire substrate

In this paper, the cone-shaped patterned sapphire substrates (PSS) were etched by an inductively couple plasma with BCl 3 as the reacting gas. The influence of the operating pressure and the RF bias power on subtrenches of the cone-shaped PSS and the formation mechanism of subtrenches were investigated. The profiles of patterns were characterized by FESEM (field emission scanning electron microscope). It showed that the subtrench size varied with the operating pressure and the RF bias power. As the operating pressure increased from 0.2 Pa to 0.9 Pa, the subtrenches changed from narrow and deep to wide and shallow; then to narrower and shallower. When the RF bias power varied from 200 W to 600 W, the subtrenches gradually became noticeable. The FESEM results also indicated that the subtrenches were formed due to the ion scattering effect which was caused by tapered sidewalls and charges accumulation. It is discovered that the scattering effect is closely related with the operating pressure and RF bias power.

Controlling synthesis and host sensitized Eu^(3+) emissions of K_5Gd_9F_(32) and GdF_3

By controlling the reactant ratios, hydrothermal time, hydrothermal temperatures, p H values of the prepared solutions, and the concentrations of K3C6H5O7·2H2O, 1 mol% Eu3+ doped cubic phase of K5Gd9F32 and/or orthorhombic phase of Gd F3 micro/nanocrystals have been synthesized based on a hydrothermal method. For comparison, the sample was also synthesized by a co-precipitation method. The samples were characterized by X-ray diffraction(XRD) patterns, field emission scanning electron microscopy(FE-SEM) images, energy-dispersive spectroscopy(EDS) spectra, and photoluminescence(PL) excitation and emission spectra. By host Gd3+ sensitizing, the Eu3+ presents relatively strong emissions. The energy transfers from host Gd3+ to doping Eu3+ are observed in all the samples and the energy transfer plays an important role in the emission of Eu3+. Acting as a probe, the Eu3+ presents its distinct optical properties in the samples.