Oak Ridge National Laboratory

About: Oak Ridge National Laboratory is a facility organization based out in Oak Ridge, Tennessee, United States. It is known for research contribution in the topics: Neutron & Ion. The organization has 31868 authors who have published 73724 publications receiving 2633689 citations. The organization is also known as: ORNL.

A Quick-Freeze Method for Making Smear Slides Permanent

Abstract: Many types of smear slides can be made permanent rapidly and effectively by substituting for the usual dehydration series a single-step process of freezing the slide on a block of dry ice, placing it immediately in 95% or absolute alcohol, and then mounting it. Advantages of the technic are its speed, the ease of separation of cover slip from slide with a minimum loss of cells, and the superiority of the resulting permanent slides.

Bamboo: an overlooked biomass resource?

Abstract: Bamboo is the common term applied to a broad group (1250 species) of large woody grasses, ranging from 10 cm to 40 m in height. Already in everyday use by about 2.5 billion people, mostly for fiber and food within Asia, bamboo may have potential as a bioenergy or fiber crop for niche markets, although some reports of its high productivity seem to be exaggerated. Literature on bamboo productivity is scarce, with most reports coming from various parts of Asia. There is little evidence overall that bamboo is significantly more productive than many other candidate bioenergy crops, but it shares a number of desirable fuel characteristics with certain other bioenergy feedstocks, such as low ash content and alkali index. Its heating value is lower than many woody biomass feedstocks but higher than most agricultural residues, grasses and straws. Although non-fuel applications of bamboo biomass may be actually more profitable than energy recovery, there may also be potential for co-production of bioenergy together with other bamboo processing. A significant drawback is the difficulty of selective breeding, given the lack of knowledge of flowering physiology. Further research is also required on propagation techniques, establishment and stand management, and mechanized harvesting needs to be developed.

Mechanisms of dissolved organic carbon adsorption on soil

Abstract: (…) In this study, the sources of DOC adsorption on two proposed waste-site soils are defined, and the chemical mechanisms operative during the adsorption process are specified. Adsorption isotherms for the two soils determined at constant pH, ionic strength (I), and temperature indicated that DOC adsorption increased with increasing soil profile depth. Different adsorption capacities were exhibited by the two soils, however, which was related to their contrasting indigenous organic matter contents and mineralogies. (…)

Identified charged particle spectra and yields in Au + Au collisions at √sNN = 200 GeV

Abstract: The centrality dependence of transverse momentum distributions and yields for ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}},{K}^{\ifmmode\pm\else\textpm\fi{}},p$, and $\overline{p}$ in $\text{Au}+\text{Au}$ collisions at $\sqrt{{s}_{NN}}=200\phantom{\rule{0.3em}{0ex}}\text{GeV}$ at midrapidity are measured by the PHENIX experiment at the Relativistic Heavy Ion Collider. We observe a clear particle mass dependence of the shapes of transverse momentum spectra in central collisions below $\ensuremath{\sim}2\phantom{\rule{0.3em}{0ex}}\text{GeV}∕c$ in ${p}_{T}$. Both mean transverse momenta and particle yields per participant pair increase from peripheral to midcentral and saturate at the most central collisions for all particle species. We also measure particle ratios of ${\ensuremath{\pi}}^{\ensuremath{-}}∕{\ensuremath{\pi}}^{+}$, ${K}^{\ensuremath{-}}∕{K}^{+}$, $\overline{p}∕p$, $K∕\ensuremath{\pi}$, $p∕\ensuremath{\pi}$, and $\overline{p}∕\ensuremath{\pi}$ as a function of ${p}_{T}$ and collision centrality. The ratios of equal mass particle yields are independent of ${p}_{T}$ and centrality within the experimental uncertainties. In central collisions at intermediate transverse momenta $\ensuremath{\sim}1.5--4.5\phantom{\rule{0.3em}{0ex}}\text{GeV}∕c$, proton and antiproton yields constitute a significant fraction of the charged hadron production and show a scaling behavior different from that of pions.

Chemically sensitive structure-imaging with a scanning transmission electron microscope

Abstract: Conventional high-resolution electron microscopy uses the phase-contrast method1, in which the diffracted beams emerging from the sample are recombined on the viewing screen of the microscope. The resultant contrast depends on the relative phases of the diffracted beams, which is sensitive to microscope and sample parameters, so that images must be interpreted by means of simulation, and defect models are somewhat empirical. By using a high-angle detector in a scanning transmission electron microscope, these problems may be avoided and high atomic-number contrast may be obtained. Here we present results of this technique applied to single crystals of the high-transition-temperature superconductors YBa2Cu3O7–x and ErBa2Cu3O7–x. The heavy-atom planes are directly imaged as bright lines, and the probable structure of an observed defect is directly inferred from its image.